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= February 1 =
== Project ==
For our project at Uni, we have been asked to pick an animal to make extinct and argue our case. It has to be a vertibrate and not man. I dont want to pick panda cos it is too obvious and it doesnt really do any harm, does it? It should be preferrably something that does harm to the environment or nature or something. I thought beaver or something. Do you agree? Any further suggestions and why?
:[[Beavers]] have a huge impact on [[ecosystem]]s, providing [[wetlands]] for many other species to use, so removing them would probably have many repercussions. From a purely [[pragmatic]] and uninformed point of view, I would argue for the extinction of a species that is critically endangered or extinct in the wild, as I would imagine this would have the lowest impact on the planet's eco-system as a whole. Flipping the assignment on its head, you could go the [[satire|satirical]] route and argue for the extinction of a species that would cause as large of an impact/disaster as possible, in effect showing that everything plays their part. [[User:Atropos235|Atropos235]] 01:20, 1 February 2007 (UTC)
:The ranchers in the American West are after timber wolf (a.k.a. [[gray wolf]]) again; they want to see it extinct in their area again. American suburbians everywhere think the [[coyote]]s should all die.
:[[User:Atlant|Atlant]] 01:21, 1 February 2007 (UTC)
= April 23 =
::Nah! I go for the [[Roadrunner]]!--[[User:Light current|Light current]] 01:33, 1 February 2007 (UTC)
== Electrocardiographic thanatography ==
:The safest thing to pick is a parasite. Not to sound utterly heartless, but humans are by far the most damaging parasite. But then, I like history and culture and being alive enough that I wouldn't want to wish the end of all humanity. This is a tough call for anyone to make. Think about the environmental impact removing a single animal would do. [[User:67.174.211.89|67.174.211.89]] 06:00, 1 February 2007 (UTC)
I read in the Vatican News that the death of Pope Francis 'was confirmed through electrocardiographic thanatography.' Wiktionary says 'thanatography' means 'An account, usually written, of the death of a person.' So the death of the Pope was confirmed through an electrocardiographic account of his death. Is this more than a complicated way to say that an ECG could not detect a heartbeat? The news also said 'The cause of Pope Francis' death has been identified as a stroke, followed by a coma and irreversible cardiocirculatory collapse.' How can the doctors know the collapse was irreversible. Does this mean the doctors tried to revive him? Thank you. [[User:Hevesli|Hevesli]] ([[User talk:Hevesli|talk]]) 08:07, 23 April 2025 (UTC)
:I'd pick an ''introduced'' species, like the [[cane toad]], and argue that it's value in it's native [[ecosystem]] is [[Trump (card game) | trumped]] by it's impact on it's [[Cane_toad#Introduction_to_Australia | introduced ecosystem]]. --[[User:Cody.pope|Cody.Pope]] 06:54, 1 February 2007 (UTC)
:Earlier in his hospitalization it was mentioned that his doctors were considering [[Do not resuscitate|not resuscitating]] him. Since this runs afoul of Catholic teaching against euthanasia, they may have couched it in terms that avoid saying, "we let him die". <span style="font-family: Cambria;"> [[User:Abductive|<span style="color: teal;">'''Abductive'''</span>]] ([[User talk:Abductive|reasoning]])</span> 11:59, 23 April 2025 (UTC)
::What makes you think that is the same as euthenasia? It can be quite an inhumane thing to use too much effort in keeping somebody 'alive'. My understanding is that the Catholic Church is not opposed to DNR notices. [[User:NadVolum|NadVolum]] ([[User talk:NadVolum|talk]]) 18:47, 23 April 2025 (UTC)
:::I dunno, ''than''atography, eu''than''asia; DNR is kinda a gray area; sure, heroics aren't always good; this is the pope so best not to have any complicated discussions even if the church isn't against DNR orders. <span style="font-family: Cambria;"> [[User:Abductive|<span style="color: teal;">'''Abductive'''</span>]] ([[User talk:Abductive|reasoning]])</span> 10:30, 24 April 2025 (UTC)
:::<small>There have been 266 catholic popes most of whom died in office so this old tale could have been about any of them. When the holy father's health worsened precariously the Vatican hospital doctors declared that they could do no more and that his life's End was imminent. Fortunately the Vatican has great financial resources and a second opinion was ordered from the highest reputed, and therefore most expensive, medical specialist. Alone with the pope the specialist gently told the sick man that he also could do nothing to save him. The old pope managed to croak a few words. "I am ready to die. Bring my lawyer to my bedside." The specialist asked "I know why I am here but why do you want a lawyer also?" Pope: "Just as my Saviour I shall die between two thieves." [[User:Philvoids|Philvoids]] ([[User talk:Philvoids|talk]]) 10:36, 24 April 2025 (UTC)</small>
= April 25 =
:What about the dreaded [[mosquito]]? | [[User:AO|<font face="Papyrus" color="Black" size="1">'''A'''</font><font face="Papyrus" color="DarkSlateGray">ndonic</font><font face="Papyrus" color="Black" size="1">'''O'''</font>]] <sup><font color="DarkSlateGray">[[User talk:AO|''Talk'']]</font> · <font color="DarkSlateGray">[[User:AO/My Autograph Book|''Sign Here'']]</font></sup> 11:39, 1 February 2007 (UTC)
== [[Absolute rotation]] ==
::Unfortunately, our questioner is limited to [[vertebrate]]s. Otherwise, the mosquito is the obvious choice.
I always imagined that (fixed) velocity was relative but acceleration (change in velocity) absolute, and that rotation was absolute being just a case of acceleration, i.e. the parts of a rotating body are constantly changing (direction of) velocity, i.e. accelerating in the general sense. However the article [[Absolute rotation]] does not even mention the word acceleration, as far as I can see. Shouldn't it? Isn't this an "easy" explanation? [[Special:Contributions/2A00:23C8:7B20:CC01:CC87:EAA5:618F:BEF8|2A00:23C8:7B20:CC01:CC87:EAA5:618F:BEF8]] ([[User talk:2A00:23C8:7B20:CC01:CC87:EAA5:618F:BEF8|talk]]) 20:45, 25 April 2025 (UTC)
::[[User:Atlant|Atlant]] 13:10, 1 February 2007 (UTC)
:It is true that the article [[Absolute rotation]] does not contain the word "acceleration". It also names Newton whose laws represent classical physics and states "From the necessary centrifugal force, one can determine one's speed of rotation;..." without explaining this use of Newton's 2nd law of motion. I agree that the article might be made more accessible if it did not assume that the general reader already knows classical Newtonian mechanics. Such improvement might be done by adding explanation as you suggest or by appropriate links to other articles. The place to propose your changes is [[Talk:Absolute_rotation]]. [[User:Philvoids|Philvoids]] ([[User talk:Philvoids|talk]]) 13:05, 26 April 2025 (UTC)
:You can really pick ''anything'' you want. It doesn't even matter. Species are rising, falling, gaining, being pushed back, [[population bottleneck|bottlenecking]], [[population explosion|exploding]], all the time everyday. It is simply the way of nature to kill off species. It may not be nice, but that's just how it is. That is normal, and it is change. It is absurd to try and do something with the intention of changing nothing, because the environment will change on its own, it doesn't matter what part of the environment changes it (may it be a particular species), because each species is part of nature. Since we are being so inherently anthropocentric, you can say humans have helped some species, and humans have destroyed some species, directly or indirectly. We can relate alien species invasion since it is the opposite of entirely removing a species. Both on the same continent and at the same time ''[[Bos taurus]]'' was being bred in vast quantities, while ''[[Bison bison]]'' was being hunted to near-extinction. Cattle are aliens too, and are among the most destructive friends we tend. The grazing and trampling of livestock threaten more than three and a half times as many native plant species globally as are threatened by nondomesticated aliens. Livestock threaten almost as many native animal species as alien predators do. ''[[Pueraria montana]]'' is an Asian plant despised in the southeastern states for aggressive growth. American gardeners of the late 1800s loved its fragrant blossoms, and in the 1920s it was promoted as ''Bos torus'' chow, and in the 30s widely planted by the [[Soil Conservation Service]] for erosion control. The [[Department of Agriculture]] declared it a weed in 1972. Similar in history, ''[[Taraxacum]] officinale'', or "common dandelion" was introduced to North America from Eurasia for its medicinal and culinary properties. Even if you don't agree with me, you perhaps should mention it to bring something new to the table. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 12:24, 1 February 2007 (UTC)
:Newtonian mechanic's accelerations are relative though, for the Galilean transformations preserve distances and time intervals, but, like the Lorentz transformations, these transformations do not preserve velocities and all accelerations. For example, consider a shipmate waving hello from a ship's bow to a beachcomber as their ship sails along the coastline and then the mate sprints to the ship's stern to wave goodbye. With respect to the ship's deck our mate first accelerated then decelerated, but from the stationary shore's reference frame they first decelerated to a slower speed and then accelerated (unless the ship slowed too) to match the ship's speed again. In short, all motion depends on reference frames, and this was true even in Newton's time when physicists speculated that motion could also be intrinsic and absolute, i.e. with respect to an absolute ether (e.g. [[Aether theories]]). [[User:Modocc|Modocc]] ([[User talk:Modocc|talk]]) 22:28, 30 April 2025 (UTC)
== Graphical solution to conservation of linear momentum problems ==
Vertebrate eh? I'd pick the Panda. Think about all the resources, time & money that have been squandered to protect or preserve a species that has become so specialized that even without our intervention, was likely to become extinct in the very near future. Are there even enough Panda's left to sustain a genetically diverse viable population?
Now if those same resources had been applied to a species not quite so cute and cuddley perhaps the passenger pigeon, great auk, or any now extinct species you can name might still be with us.
This then brings into question the entire reason why we choose to protect some species while ignoring others? If the Panda was an ugly mollusc that crawled up your leg and bit you on the ass, would we be so willing to protect it?
Extinction is a natural process. It is not that extinction occurs that should concern us rather, the acclerated rate of extinction that we as a species seem to be responsible for.
Canis sylvaticus
[[File:Linear_momentum_conservation_2d.svg|thumb|Graphical solution to an example conservation of linear momentum problem:<br />1. A 3 g ball moving south at 2 m/s collides with a 2 g ball moving northeast at √8 m/s. If the 2 g ball reverses course at half its initial speed, how is the 3 g ball deflected? If instead the collision were perfectly inelastic, how do the balls move?<br />2. Vectors representing each momentum is drawn by multiplying each mass and velocity, keeping the resultant momentum before and after the collision the same.<br />3. Dividing the magnitude of the vector by its mass gives the desired velocity: 2 m/s eastwards. A perfectly inelastic collision would make the balls move together as a 5 g mass in the direction of the resultant dashed purple arrow at 2√5/5 m/s.]]
::How about the [[Water moccasin]] or [[Copperhead snake]]?, or maybe the [[Rattlesnake]]? Your study could look at whether nonvenomous species could step up to replace their pest control benefits without harming humans. In other words, would we be overrun by rats and mice without the venomous snakes, or could the less harmful species take care of the pests. These species do harm humans and their pets and livestock, and the water moccasin and copperhead snakes make the enjoyment of the outdoors difficult in the southern US in the summer, as the rattlesnake does in the west. I acknowledge that many people love all animals, and that they are all pretty to look at, unless you have just stepped over a log and they have sunk their fangs into your leg. (edited to add: Here I refer to the snakes, not the animal lovers as biters). Keep the panda. They do not bite humans as often, and are not known to be venomous. [[User:Edison|Edison]] 16:38, 1 February 2007 (UTC)
I found a technique to solve conservation of linear momentum problems by drawing a diagram, as illustrated.
:::Human deaths from venomous snake bites in the USA (those species in particular are US snakes, yes?) are so uncommon today as to be statistically negligible. You get far more deaths from dog bites per year, more deaths related to riding the bus. --[[User:140.247.248.95|140.247.248.95]] 17:33, 1 February 2007 (UTC)
::::Country people in the southern U.S. avoid wooded or grassy areas, or creekbanks in the southern US in weather above freezing because of the presence of copperheads. They are numerous and aggressive, and like to live near human habitation, and move into outbuildings or onto farm equipment. I have had several close calls. Besides deaths, they cause painful injuries with lengthy recuperation. No one claimed that poisonous snakes are leading cause of deaths, and more people obviously ride buses that step on copperheads. Dogs are domesticated pets and offer the benefit of companionship or guarding as a tradeoff for the chances of biting soemone. Copperheads make poor pets, but if it were known that they lived in a building, people would, I guess, pretty much stay out. [[User:Edison|Edison]] 21:43, 1 February 2007 (UTC)
:::::I'm just pointing out that you'd have to indicate that the number of lives you'd be saving would be in the dozens, whereas the likely ecological damage would be quite high. In terms of cost/benefit the panda is an easy one in comparison to the venomous snakes of the US, which cost very little (in terms of human costs and resources) to live with. The panda's non-venomous quality does not really give it an edge over the snakes in a strictly utilitarian model. --[[User:24.147.86.187|24.147.86.187]] 00:22, 2 February 2007 (UTC)
If the collision were instead elastic i.e. kinetic energy is conserved, is it possible to find all possible solutions graphically? Thanks, '''[[User:cmglee|cmɢʟee]]'''⎆[[User_Talk:cmglee|τaʟκ]] 22:17, 25 April 2025 (UTC)
I'm sure if you made your presentation on a list of animals you initially thought you might like to make extinct, then talked about what made you reconsider, and concluded the whole exericse to be abhorrent, you would not receive an autofail. That's what I'd do. [[User:Vranak|Vranak]]
:I'm not sure if there is a graphical approach to solving for area (ie v^2), I've never seen one. [[User:Greglocock|Greglocock]] ([[User talk:Greglocock|talk]]) 00:30, 26 April 2025 (UTC)
----
:[[File:Thales'_Theorem_Simple.svg|thumb|none|Thales's theorem]]
I would pick the [[goat]] or the [[Norway Rat]]. Goats devastate ecosystems, and rats have a huge impact on humans. The one you pick will depend on your perspective. -[[User:Arch dude|Arch dude]] 02:39, 2 February 2007 (UTC)
:Can one conclude that if the two balls had the same mass ''m'', one could use [[Thales's theorem]] to state that if '''AC''' is the resultant vector in the diagram, the constituent vectors are '''AB''' and '''BC''' for any B on the circle, so that <span style="white-space:nowrap;">|'''AB'''|² + |'''BC'''|² = |'''AC'''|²</span> to conserve kinetic energy i.e. <span style="white-space:nowrap;">½''mv''₁² + ½''mv''₂² = constant</span>? Cheers, '''[[User:cmglee|cmɢʟee]]'''⎆[[User_Talk:cmglee|τaʟκ]] 12:12, 28 April 2025 (UTC)
::If the balls have the same mass, then isn't the solution quite simple for perfectly elastic collision? Velocity components along the line between the two centres swapped between the balls, and perpendicular components unchanged. (Someone please correct if this is wrong!) With balls of different mass, the solution algebraically most probably involves some multiplications, additions and divisions, all of which can in theory be done "graphically" using ruler and compass, but of course it could get very messy in practice. A neat graphical solution is a bigger ask. [[Special:Contributions/2A00:23C8:7B20:CC01:DCDC:39AB:FED1:9A1B|2A00:23C8:7B20:CC01:DCDC:39AB:FED1:9A1B]] ([[User talk:2A00:23C8:7B20:CC01:DCDC:39AB:FED1:9A1B|talk]]) 18:27, 28 April 2025 (UTC)
:::You're right, thanks. I hadn't considered it. '''[[User:cmglee|cmɢʟee]]'''⎆[[User_Talk:cmglee|τaʟκ]] 10:51, 29 April 2025 (UTC)
{{clear}}
: If you want to be a smartass you could go for the [[Madagascar Pochard]]. The rationale being that everyone thought it was extinct 15 years ago anyway, and the world kept turning. Then a few of them were spotted last year. However, they are clearly critically endangered and - one could argue - removing the few remaining would have a negligible environmental impact. The opposing argument is that the Madagascar flora and fauna is rich in genetic diversity. [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 06:21, 2 February 2007 (UTC)
::Excellent idea! [[Frilled shark]], [[Megamouth]], [[coelacanth]], and [[Lazarus taxon]]. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 18:03, 2 February 2007 (UTC)
= April 28 =
And the Tazmanian wolf
== purifyingIdentifying watera and sourdoughtulip ==
[[File:Yellow tulips with red flames.jpg|thumb|left]]
I have recently heard that the brewing industry use to use sourdough (from bread) to purify water. I wondered if there was anyone who could validate this. Also, how does it work? Thanks Valerie
Anyone know what this is? It's quite striking. It seems to be a tulip of some kind, but I don't know what. Google says it's a [[Tulipa hungarica]], but it doesn't look all that similar to my untrained eye. Would like to identify it correctly on Commons if possible. [[User:NinjaRobotPirate|NinjaRobotPirate]] ([[User talk:NinjaRobotPirate|talk]]) 02:44, 28 April 2025 (UTC)
:[[Sourdough bread]] is bread that is leavened with sourdough starter, a symbiotic colony of yeast and bacteria (lactobacilli). The closest to "purifing" water might be the microorganisms living in the starter form somewhat hostile conditions to "squeeze out" other potential micro-invaders.That process is fairly slow and complex compared to filtering water through [[activated charcoal]] or [[distillation]], and you'd end up with a bunch of floury water. I'm not a big [[beer]] aficionado, but using some sourdough starter in a ferment might impart some of the same acidic, complex flavors you can get in sourdough bread. [[User:Atropos235|Atropos235]] 02:44, 1 February 2007 (UTC)
:When I Google "yellow tulip with red flames" I'm told it's Tulip Olympic Flame, which does appear the same. [[User:Shantavira|Shantavira]]|[[User talk:Shantavira|<sup>feed me</sup>]] 08:37, 28 April 2025 (UTC)
:Is it at all possible that this is a garbled version of the idea that alcoholic drinks were once drunk in great quantity because they were less likely to poison you than the water? That was mostly (if not entirely) due to the boiling involved in the production of alcoholic drinks. [[User:Skittle|Skittle]] 15:36, 1 February 2007 (UTC)
:It's a [[tulip]] and not a Tulipa hungarica, at least not a pure one; note the rounded [[tepal]]s and the red flames. There are many species of tulips, many hybrids and countless [[cultivar]]s, some of which managed to escape into the wild. To identify a particular species or, in case of a hybrid, combination of species, one may need a genetic study. I suspect this is some cultivar; one possibility has been mentioned above.
:The flames may be from genetics (and usually are in cultivars), but can also be caused by a viral infection. [[User:PiusImpavidus|PiusImpavidus]] ([[User talk:PiusImpavidus|talk]]) 09:12, 28 April 2025 (UTC)
:The same tulip is available at J Parkers in the UK, they call it Tulip 'Flaming Sun', https://www.jparkers.co.uk/tulip-flaming-sun-1112cm-collection-1 [[User:Stanleykswong|Stanleykswong]] ([[User talk:Stanleykswong|talk]]) 05:30, 30 April 2025 (UTC)
I just spent 15 minutes looking at tulip images. To me, your photo is of the "Fire Wing Tulip" which is thought to be part of the Tulipa Darwin Hybrid Group or Tulipa Triumph Group (both of those have categories on Commons). Olympic Flame is also part of the Tulipa Darwin Hybrid, but your tulips don't look like Olympic Flame. [[User:Viriditas|Viriditas]] ([[User talk:Viriditas|talk]]) 02:28, 30 April 2025 (UTC)
== Petroleum Oil ==
: Interesting. Fire Wing does look similar. [[User:NinjaRobotPirate|NinjaRobotPirate]] ([[User talk:NinjaRobotPirate|talk]]) 00:10, 1 May 2025 (UTC)
::I was surprised to learn that Fire Wing is new, and was only recently created in the early 2000s. Some of the Fire Wing images are different and don't look like yours, while others do, so I think the jury is still out. Given that Olympic Flame and Fire Wing may both trace to the Tulipa Darwin Hybrid Group, I wonder if that is something you can go on to look further. The last time I grew tulips was in 1996. I bought a huge bag of bulbs from Costco, who had at that time received a direct shipment from the Netherlands. [[User:Viriditas|Viriditas]] ([[User talk:Viriditas|talk]]) 00:14, 1 May 2025 (UTC)
::: These tulips were most likely planted by a professional who had access to rare cultivars, which unfortunately does complicate the issue. He's no longer available, but there are a lot of pretty flowers in the area. [[User:NinjaRobotPirate|NinjaRobotPirate]] ([[User talk:NinjaRobotPirate|talk]]) 00:26, 1 May 2025 (UTC)
:"Fire Wings tulip" is similar in appearance to "Flaming Sun tulip", but has more pointed petals. [[User:Stanleykswong|Stanleykswong]] ([[User talk:Stanleykswong|talk]]) 07:05, 1 May 2025 (UTC)
= April 30 =
I am doing a science fair project for my 8th grade class. My question that i want to ask you is this: What is oil's real purpose in the Earth? Does is it act like some sort of insultaor or anything else? I mean, everthing on this Earth is here for a purpose. I am stuck and do not know what to do. I found one website that asked the same question to but did not have any information that I needed. {{Please Help Me}} [[User:4.129.87.148|4.129.87.148]] 00:57, 1 February 2007 (UTC)
== Baa baa choo choo ==
:[[Petroleum|Oil]] wasn't intentionally placed into the Earth for any sort of reason, but it is just the result of dead biomatter being compressed and heated under millions of years of sediment. Man's persistant exploration of the world lead to the discovery of petroleum and its seemingly millions of uses over the ages, from lighting up ancient homes to sending people to the moon. It can easily seem like everything in the world has a purpose because we are the ultimate tool-users and we can find a purpose for just about anything. [[User:Atropos235|Atropos235]] 01:36, 1 February 2007 (UTC)
What was the maximum speed of [[Russian locomotive class O|one of '''these''' "little sheep"]] while pulling a train of 400 tons? I was only able to find the maximum speed when travelling light (50-55 km/h) -- by how much would a 400-ton train (such as a typical [[armored train]] from [[World War 1|that era]]) slow it down? [[Special:Contributions/2601:646:8082:BA0:D86C:E2FE:4764:1AB0|2601:646:8082:BA0:D86C:E2FE:4764:1AB0]] ([[User talk:2601:646:8082:BA0:D86C:E2FE:4764:1AB0|talk]]) 03:19, 30 April 2025 (UTC)
::For all we can tell, ''purpose'' is not inherently present on anything. There's no purpose for the existence and presence of oil, or even life, on Earth. It exists because that's how chemistry and physics work. Things also tend to naturally find their most stable state throughout time, so the feeling of deliberation and purpose arises naturally everywhere, since everything ends up fitting together so well. That being said, oil has no purpose, we just happen to find it very, very useful for [[petroleum#Uses|many different things]]. — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 01:44, 1 February 2007 (UTC)
:The Russian Wikipedia gives the [[traction]] as 8700—9500 [[kgf]]. At which speed does [[rolling resistance]] + [[drag (physics)|drag]] of a typical 400-ton train equal about 9000 kgf? (Are these [[metric ton]]s?) I bet this is an order of magnitude higher than 50–55 km/h, so my best guess is that it takes 15 to 30 minutes for the train to come up to maximum speed, but that speed would still be in the 50–55 km/h range. ​‑‑[[User talk:Lambiam#top|Lambiam]] 08:47, 30 April 2025 (UTC)
:::The scientific way to phrase it is that ''purpose'' is not scientifically testable in experiment and therefore not relevant in a scientific sense. However, to absolutely claim there is no ''purpose'' is making a leap that science cannot explain so claiming there is no ''purpose'' or ''deliberation'' goes beyond the scientific method. --[[User:OpusPenguin|OpusPenguin]] 03:17, 1 February 2007 (UTC)
:At 1.85 square metres of [[grate area]] and a somewhat realistic efficiency, I guesstimate that its sustained power is no more than about 100 to 150 kilowatts. With the rolling resistance of a 400 tonne train, that's maybe 40 km/h. But with the cut-off wide open for more traction, efficiency drops. Could be interesting to look into, but I've no time right now. [[User:PiusImpavidus|PiusImpavidus]] ([[User talk:PiusImpavidus|talk]]) 16:19, 30 April 2025 (UTC)
::The Russian Wikipedia gives the power as 550—720 hp, which amounts to about 400—530 kW. ​‑‑[[User talk:Lambiam#top|Lambiam]] 22:27, 30 April 2025 (UTC)
:::It was a very rough guesstimate. In any case, it serves to demonstrate that it's most likely limited by sustained power, not by traction. At 85 kN traction, 400 kW power is reached at only 17 km/h.
:::All versions appear to have had the same firebox, so differences in sustained power can only be caused by differences in efficiency. And the slower you go, the more traction you need to reach maximum power, so a later [[cut-off (steam engine)|cut-off]], leading to less efficiency and less power. The 400 to 530 kW figure may have been measured using a train of less than 400 tonnes, giving more power. Although not too light a train, as power would normally mean drawbar power, which gets less if the train is too light and a larger fraction of the power is wasted on moving the loco itself.
:::To get an accurate answer, we need detailed performance data on these locomotives, and considering that steam locomotive design was often more art than engineering, such data may never have been collected. Absent that, any number between 30 and 45 km/h sounds totally believable to me. [[User:PiusImpavidus|PiusImpavidus]] ([[User talk:PiusImpavidus|talk]]) 11:00, 1 May 2025 (UTC)
= May 1 =
:I personally believe "everything having a purpose" to be rubbish. As [[Richard Dawkins]] said, "We see the world through purpose-colored [[spectacles]]," because our nature is to see objects of having potential uses to us, we assume if we can't use it, it has a use to some other organism. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 12:17, 1 February 2007 (UTC)
== Why don't humans (usually) ride rhinoceri? ==
See [[Teleology]] for a discussion of the old notion that someone (God?) placed everything herre for a purpose. This view might say that if I am hiking and have to make a pitstop in the woods, that my excrement is there for the purpose of nourishing a bush which will grow into a tree and provide shelter for some future weary travellor. A less teleological and more naturalistic view might be that "excrement happens." [[User:Edison|Edison]] 16:44, 1 February 2007 (UTC)
I know it's been done occasionally (there are photos if you Google it), but why is it that rhinos are generally considered unsuitable to use as mounts, while elephants have been ridden for centuries? [[Special:Contributions/146.200.107.90|146.200.107.90]] ([[User talk:146.200.107.90|talk]]) 00:53, 1 May 2025 (UTC)
: If you were to put any purpose to oil, surely it would be to warm up the Earth, not that there's anything wrong with that. [[User:Vranak|Vranak]]
:Indian elephants are domesticated. African elephants, as well as rhinos and hippos, are wild and dangerous. (Aside: There's more than one plural for rhinoceros, but rhinoceri is not on the list.[https://www.etymonline.com/search?q=rhinoceros]) ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 02:04, 1 May 2025 (UTC)
::Similarly, humans have been riding horses for about 6000 years. Humans do not regularly ride zebras despite their similarity in form and genetics to horses. Zebras cannot be domesticated despite many attempts. Some have been tamed enough to pull carts but not to ride. 02:16, 1 May 2025 (UTC) -- Cullen328
:::I saw something about zebras not too long ago. I think it said that in addition to being wild and ornery, their backs are not strong enough to support riders. As I recall, when they did a movie about Sheena or some such, the "zebra" she rode on was actually a regular horse painted with zebra stripes. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 02:29, 1 May 2025 (UTC)
::::Maybe it's because it's difficult to get glasses or contact lenses for rhinos. I have never seen one in an optician's office, although I need a new prescription so I might have missed them. [[User:Sean.hoyland|Sean.hoyland]] ([[User talk:Sean.hoyland|talk]]) 03:53, 1 May 2025 (UTC)
:::::Especially if they're suffering from a rhinovirus. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 04:19, 1 May 2025 (UTC)
:::Wild horses aren't very suited to riding either. People invented [[chariot]]s before [[cavalry]], not only because it took a while to develop proper saddles and stirrups, but also to breed the right horse breeds. [[User:PiusImpavidus|PiusImpavidus]] ([[User talk:PiusImpavidus|talk]]) 12:02, 1 May 2025 (UTC)
:::Fwiw, Google images has several photos of people riding zebras. So it can be done. Occasionally, I guess. [[Special:Contributions/146.200.107.90|146.200.107.90]] ([[User talk:146.200.107.90|talk]]) 13:15, 1 May 2025 (UTC)
::::[[Zebra]] says: "{{tq|In the early 20th century, [[German East Africa|German colonial officers in East Africa]] tried to use zebras for both driving and riding, with limited success.}}" [[User:Martinevans123|Martinevans123]] ([[User talk:Martinevans123|talk]]) 13:19, 1 May 2025 (UTC)
::Didn't Hannibal and his guys famously ride African elephants across the Alps? [[Special:Contributions/146.200.107.90|146.200.107.90]] ([[User talk:146.200.107.90|talk]]) 13:17, 1 May 2025 (UTC)
:::He used a different species, [[North African elephant]], which is now extinct. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 14:48, 1 May 2025 (UTC)
::::Did the Romans wipe them out? [[User:Tamfang|—Tamfang]] ([[User talk:Tamfang|talk]]) 19:24, 4 May 2025 (UTC)
:::::According to the article, Yes. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 20:01, 4 May 2025 (UTC)
:Rhinos are considered the 4th most ferocious animals in the world (right after the [[African elephant]], the [[African killer bee]] -- WTF, no article?! -- and the [[sun bear]], in that order), so this is probably the reason why. [[Special:Contributions/2601:646:8082:BA0:F051:2F1F:9C50:8350|2601:646:8082:BA0:F051:2F1F:9C50:8350]] ([[User talk:2601:646:8082:BA0:F051:2F1F:9C50:8350|talk]]) 10:20, 1 May 2025 (UTC)
::IP editor. I think you want the [[Africanized bee]] article. [[User:Michael D. Turnbull|Mike Turnbull]] ([[User talk:Michael D. Turnbull|talk]]) 10:46, 1 May 2025 (UTC)
::[[Pillywiggin|Riding African killer bees]] might be tricky, but probably [[BeRider|ecologically sound]]. [[User:Martinevans123|Martinevans123]] ([[User talk:Martinevans123|talk]]) 10:59, 1 May 2025 (UTC)
:The rhinoceros doesn't even make it to this list [https://www.discoverwildlife.com/animal-facts/deadliest-animals-to-humans]. [[User:NadVolum|NadVolum]] ([[User talk:NadVolum|talk]]) 11:40, 1 May 2025 (UTC)
:Taming and domesticating are different concepts. When taming an animal, humans change their behaviour to make them more willing to cooperate with humans. When domesticating an organism (not necessarily an animal), its genetics are changed to make them more suited to what humans want to do with them. Arguably, elephants have been tamed, but not domesticated (tame working elephants are usually female and impregnated by wild males, so genetically they're still wild) and silkworms have been domesticated, but not tamed. Any species that can be bred in captivity can be domesticated, but not necessarily tamed. Social animals, like elephants, horses, buffalos and wolves, are usually easier to tame than solitary animals like rhinos, but that's not a very hard rule. Smarter animals also tend to be easier to tame, as they have more learned and less instinctive behaviour. Animals that have been tamed are easier to domesticate (as one can handle them in captivity), animals that have been domesticated can be easier to tame (after selective breeding to make them more cooperative) and provide higher rewards after taming (as they can do more useful jobs).
:Some issues with riding rhinos appear to be:
:*As a solitary animal, it may be harder to tame.
:*They are dangerous. When taming an animal, most people prefer one that's less likely to kill them.
:*Rhinos procreate slowly and need a huge pasture, making selective breeding expensive.
:*Like elephants, they are too large to be efficient people movers, limiting their use to moving goods and VIPs.
:[[User:PiusImpavidus|PiusImpavidus]] ([[User talk:PiusImpavidus|talk]]) 12:58, 1 May 2025 (UTC)
::[[Year of the Elephant]]. [[Special:Contributions/2A02:C7C:F0EC:ED00:B968:4A6C:C17D:3311|2A02:C7C:F0EC:ED00:B968:4A6C:C17D:3311]] ([[User talk:2A02:C7C:F0EC:ED00:B968:4A6C:C17D:3311|talk]]) 15:27, 1 May 2025 (UTC)
:[[Indian Rhinoceros]]es have been killing people rather frequently: [https://www.theguardian.com/environment/2025/apr/16/conservation-success-rhinos-nepal-human-conflict-towns-chitwan-national-park-aoe '''Sauntering on streets and grazing on lawns: what happens when rhinos move into town?''' ] [[User:Modocc|Modocc]] ([[User talk:Modocc|talk]]) 00:04, 2 May 2025 (UTC)
<small>Meta-pedantic peeve: When you use a pedantic plural, make sure you actually get it right. Without looking it up, <s>I'm pretty sure the word you want is ''rhinocerontes''</s>. Or, you know, just rhinoceroses is also fine. --[[User:Trovatore|Trovatore]] ([[User talk:Trovatore|talk]]) 19:15, 1 May 2025 (UTC) </small> UPDATE: Looked it up and I can't find ''rhinocerontes''; closest is Spanish ''rinocerontes'' without the h. Extrapolating from the ancient Greek it looks like it could maybe be ''rhinocerata'', given that ''κέρᾰτᾰ'' is the nominative and accusative plural of ''κέρᾰς'', "horn". --[[User:Trovatore|Trovatore]] ([[User talk:Trovatore|talk]]) 19:48, 1 May 2025 (UTC)
You are in 8th grade. Teleology is usually considered to be way too heavy for your age: [[Plato]] thought that one should not be concerned with [[Philosophy]] until age 40. Science fair: you are probably in time trouble: you don't need generalities, you need an answer, NOW. Here is what we are trying to tell you in simple terms:
* forget "purpose." That is way too complicated. It is philosophy, not science.
* Try to rephrase your hypothesis into something more scientific and less philosophical.
If you can reply with your current hypothesis, We can probably critique it for you and suggest a better hypothesis. I just got home from judging a high-school Science Fair, so I am sympathetic. -[[User:Arch dude|Arch dude]] 02:33, 2 February 2007 (UTC)
:The Ancient Greek plural is {{serif|ῥινοκέρωτες}}, not *{{serif|ῥινοκέροντες}} or *{{serif|ῥινοκέρατα}}. Wiktionary lists ''[[wikt:rhinocerotes|rhinocerotes]]'', coming to us via Latin from Greek, labeling it as "''now rare''". ​‑‑[[User talk:Lambiam#top|Lambiam]] 22:08, 1 May 2025 (UTC)
:: What did Plato know? Him and his ilk never understood [[inertia]] nor [[evolution]] nor [[planetary harmonics]]. Nonetheless, the above statements correctly emphasize that '''purpose is not testable and has no place in science. '''We can study much about [[petroleum]] - how it forms, what it is made of, what we can make out of it... but none of this implies a [[purpose]]. However, I think the original question was asking whether there petroleum '''performs a geological function''' - such as "insulating. "Petroleum reserves do not really insulate very much; but they contain lots of dissolved gases (notably, [[helium]], sometimes [[hydrogen]], and very often [[methane]] or other [[natural gas]].They also serve as boundaries between rock layers (though this is probably an effect due to their formation). [[User:Nimur|Nimur]] 08:05, 2 February 2007 (UTC)
::Its plural is'' rhinoceroses'' according to Google's AI [https://www.google.com/search?client=firefox-b-1-d&q=rhinoceros+plural] and ''rhinoceri'' places a distant second in occurrences. [https://books.google.com/ngrams/graph?content=rhinoceroses%2Crhinocerotes%2Crhinocerota%2Crhinocerata%2Crhinoceri%2Crhinoceroi%2Crhinocerosses&year_start=1800&year_end=2000&corpus=en-2012&smoothing=3] [[User:Modocc|Modocc]] ([[User talk:Modocc|talk]]) 22:34, 1 May 2025 (UTC)
:::Thanks {{u|Lambiam}} and {{u|Modocc}}; good info. I still think if you're going to go for pedantic and say ''rhinoceri'', you might as well go all the way to diatopically/diachronically correct and say ''rhinocerotes''. --[[User:Trovatore|Trovatore]] ([[User talk:Trovatore|talk]]) 02:59, 2 May 2025 (UTC) For avoidance of doubt, presumably pronounced /raɪnɔːsɛroʊtiːz/, rye-naw-seh-ROTE-eez. --[[User:Trovatore|Trovatore]] ([[User talk:Trovatore|talk]]) 03:10, 2 May 2025 (UTC)
:Given that ''ceros'' ≠ κέρᾰς, I would not bet on κέρᾰτᾰ. I'd have guessed ''ceroi''.
:At least OP did not go with ''cerii''. [[User:Tamfang|—Tamfang]] ([[User talk:Tamfang|talk]]) 19:27, 4 May 2025 (UTC)
::Ride 'em [[Spearmint Rhino|cowboy]]! [[User:Martinevans123|Martinevans123]] ([[User talk:Martinevans123|talk]]) 19:39, 4 May 2025 (UTC)
:Since no one actually gave the simple answer to your questions, I will: The purpose of the oil is for people to burn it for fuel. Do you think it needs some other reason to be there? [[User:Ariel.|Ariel.]] 13:11, 4 February 2007 (UTC)
= May 2 =
== Database for lab experiments ==
Hello,
I am currently working on my PhD in the biopharmaceutical field. I am doing a number of lab experiments and I am looking for a way to store information about the experiments and the outcomes in a database.
== Newton ==
Typical data about an experiment would be: Title, notes, Dates (when run, when analysed), material used, method used (i.e. word files), raw data (i.e. sampling points), secondary data (i.e. halflifes), graphs.
Whence comes this misconception that the apple fell '''on''' [[Isaac Newton]]'s head when he first got the idea about the [[law of gravitation]]? Anyone know the source of the confusion? [[Special:Contributions/2601:646:8082:BA0:84C8:522A:EF41:5D|2601:646:8082:BA0:84C8:522A:EF41:5D]] ([[User talk:2601:646:8082:BA0:84C8:522A:EF41:5D|talk]]) 05:31, 2 May 2025 (UTC)
I have attempted to come up with an MSAccess solution, it works more or less but it has its bugs and entering data can be somewhat time consuming.
:The oldest recorded source may be a letter by [[Euler]], dated 3rd September 1760. In translation:
I was wondering if anyone knows a flexible tool to handle this kind of task.
::{{serif|This great English philoſopher and geometrician, happening one day to be lying under an apple-tree, an apple fell upon his head, and ſuggested to him a multitude of reflections.}}<sup>[https://books.google.com/books?id=_1oIAAAAIAAJ&pg=PA202&dq=%22an+apple+fell+upon+his+head%22&hl=en]</sup>
(I think there should be, since the core of what I need it to do is probably needed by uncountable other people working in similar areas. I haven't really found anything practical so far though).
:If the story of a falling apple being a source of inspiration is true at all, we cannot be certain that said apple did not actually land on the great philosopher's noggin. In Voltaire's poem, Newton ''saw'' the apple falling, but neither Conduitt's nor Stukeley's account (see {{section link|Isaac Newton%27s apple tree#The apple incident}}) states that the observation was visual. Conduitt writes that the apple landed "on the ground", but this may have been his assumption if Newton, regaling others of his inspiration story, left the somewhat ignominious landing site unspecified. ​‑‑[[User talk:Lambiam#top|Lambiam]] 08:09, 2 May 2025 (UTC)
::Thanks! So, probably a case of [[Chinese whispers]] about the incident, then? [[Special:Contributions/2601:646:8082:BA0:8029:3AF8:59DC:7A79|2601:646:8082:BA0:8029:3AF8:59DC:7A79]] ([[User talk:2601:646:8082:BA0:8029:3AF8:59DC:7A79|talk]]) 12:04, 2 May 2025 (UTC)
:::It makes for a more colorful story if it literally hit him on the head, rather than just metaphorically. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 15:40, 2 May 2025 (UTC)
== Black five ==
Thanks, [[User:Lukas.S|Lukas]] 04:32, 1 February 2007 (UTC)
Is it true that on a [[William Stanier|Stanier]] [[Black Five]], when running flat-out, the [[boiler]] could actually boil the water faster than the [[injector]] could pump it in? I've done the calculations for the maximum steaming rate earlier today (based on the boiler being able to make just enough steam to supply the cylinders at 55 mph with full throttle and 15% [[cutoff]]), and by my calculations the boiler can [[vaporize]] a maximum of 10.2 gallons of water per minute -- is this an accurate estimate, and if so, is it more than the maximum [[flow rate]] through the injector? [[Special:Contributions/2601:646:8082:BA0:79DE:B608:5A9E:D281|2601:646:8082:BA0:79DE:B608:5A9E:D281]] ([[User talk:2601:646:8082:BA0:79DE:B608:5A9E:D281|talk]]) 06:18, 2 May 2025 (UTC)
:Honestly, I'd use a spreadsheet if you don't have any prior experience with RDBMSes. Spreadsheet software is very flexible and useful for sufficiently small amounts of data. Most of the data I need to process goes directly from my notebooks into a spreadsheet program. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-01T05:50Z</code>
:I'm no specialist on the Stanier Black Five, but since nobody answered within 24 hour...
::I don't think you could include all of the data he wants in just that. However it sounds to me like it is a flat database anyway, so you don't necessarily need it to be relational. Have you tried something like [[FileMaker Pro]]? It is like MS Access but much simpler on the whole. It doesn't let you do as complicated or customized things with the data but it doesn't sound like you are using Access to its full capabilities anyway. Access is probably the most "flexible" thing you are going to find, but being able to use that capability well requires a lot of time and experience with it. If you wanted to post the nature of the bugs to the computing desk, I am betting we can iron out some of them (I say this as someone who has wrestled with Access for eight years or so at this point). --[[User:24.147.86.187|24.147.86.187]] 12:49, 1 February 2007 (UTC)
:With such cylinder dimensions and at 15% cut-off, it uses 18.5 litres of high-pressure steam per stroke. At 55 mph (one Black Five reached 96 mph, but this may have been on the downhill), such wheels and 4 strokes per revolution, that's 17 strokes per second. Combined, that's 317 litres of steam per second. I don't know the density of that steam (because I don't know the temperature after the superheater), but I suppose something like 3–5 grammes per litre, so that's somewhere around a kilogramme per second. Your 10.2 gallons per minute equals 765 grammes per second (assuming those are Imperial gallons, it's after all a British locomotive; your IP ___location, time of posting and spelling suggest however that your gallons may be smaller), so that's close. With the given grate area, this is more or less what's expected. So yes, your estimate appears reasonably accurate.
:Now keep in mind (you probably know this, but I'll mention it anyway) that with steam locomotives there's a big difference between sustained power and peak power; sustained steam use and peak steam use. You can extract a huge amount of power and steam out of the boiler by letting water level, temperature and pressure drop, much more than the fire and injectors can provide. This is nice, as trains need more peak power than sustained power, and explains why big firetube boilers are good, despite being slow to bring up to working pressure. I suppose the question is about sustained steam generation.
:Having a firebox that can heat water from room temperature (or a bit hotter, assuming a pre-heater) to 200°C and then boil it faster than your injector can provide this water has some advantages. There's a faster cold start and peak power can be sustained longer, as pressure drops less fast. The cost is a faster drop in water level. Having oversized injectors also has an advantage: you can quickly fill the boiler, at the expense of a pressure drop, which may be good when cresting a summit. On the descent, you don't need boiler pressure, but you do need high water level to keep the crown sheet, now at the high end of the boiler, covered. I suspect engineers (=the people designing them) typically aimed to have the injectors somewhat oversized compared to the grate, also because injectors are cheap compared to grate area. Less than optimal designs were common though, as engineers often worked more on experience and educated guesses than on science.
:I don't know about the injectors on the Stanier Black Five.
:Most locomotives had two injectors. On express locos, often one was powered by exhaust steam (after the cylinders, before the blast pipe, there was enough pressure left) and running whenever the loco was moving. The other was powered by steam directly from the boiler and used only when more water was needed. The exhaust injector, working on lower pressure steam, would have less capacity than the live injector, even more so at short cut-off. [[User:PiusImpavidus|PiusImpavidus]] ([[User talk:PiusImpavidus|talk]]) 10:13, 3 May 2025 (UTC)
== Looking for an old wiki article on Mechanical Engineering Mathematics of Connected Bodies ==
:::Well, he didn't specify how much data he is working with...If we're talking single data sets with a million rows, then a spreadsheet will be insufficient. A few thousand rows is reasonable, though. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-01T15:08Z</code>
Around the late 2010s decade or maybe early 2020s, I came across a Wikipedia article about the mechanical engineering mathematics of connected bodies (by something like a string, for example). I do not remember the title of the article, but it had a parenthesis term at the end of its title, like (mechanics) or (engineering) or (kinetics) or , but I don't remember the word exactly.
::::I'm not talking about total records. Look at the types of data he describes -- Word files, lengthy descriptions, etc. It is not easy to do that in a spreadsheet program, at least not any I have seen. The lines get very long and hard to read, use, and edit. --[[User:140.247.248.95|140.247.248.95]] 17:27, 1 February 2007 (UTC)
The article may have been similar to the articles "[[Dynamics (mechanics)]]" or "[[Linkage (mechanical)]]" or "[[Tension (physics)]]", except it was about a very specific topic. The article may have been related to categories like "[[:Category:Mechanics]]" or "[[:Category:Dynamics (mechanics)]]".
::::Need to share the data among workers ? Why not try a hosted DB solution like www.teamdesk.net at 7 $ / month / user. I found it easy to customize. [[User:Pcarbonn|Pcarbonn]] 16:03, 1 February 2007 (UTC)
The article has either been deleted, renamed or changed so much that I no longer recognize it. I was interested in it because it seemed like it could be relevant to a topic I am studying, the [[n-body problem]].
::Be '''very''' careful when using spreadsheets to store experiment results. See for instance [http://itre.cis.upenn.edu/~myl/languagelog/archives/002912.html The December 1 DWIM effect] (reported on [[RISKS Digest]] 24.19; some comments on 24.20 and 24.21). Some other spreadsheet horror stories can be found at the [http://www.eusprig.org/stories.htm European Spreadsheet Risks Interest Group] site. --[[User:CesarB|cesarb]] 18:57, 1 February 2007 (UTC)
If you know the topic that I am talking about, please let me know. [[User:Cerebrality|Cerebrality]] ([[User talk:Cerebrality|talk]]) 12:42, 2 May 2025 (UTC)
Thanks for the replies so far. Especially thanks for the warning on excel, I've encountered some bugs in it myself before. Excel/spreadsheed is not a viable option for me.
The reason to use the database is, as correctly pointed out, not that I have thousands of records, but that I have descriptive text data, files, etc. I do not need to share the data (and I don't see that happening within this project).
I want to be able to easily enter data into a form and retrieve data matching certain characteristics (this is what I have attempted in my test database (msaccess2002). One thing it should take over is the task to think of where I should save which files and make it easy for me to find them again. I'm still looking for a product or an msaccess template which is designed for this or a similar purpose (there are should be tons of other people out there with similar requirements as me....). [[User:Lukas.S|Lukas]] 01:47, 2 February 2007 (UTC)
:@[[User:Cerebrality|Cerebrality]] AI is getting better. I asked [[MS Bing]] "what is the wikipedia article about mechanical engineering mathematics of connected bodies?" and it said [[Kinematic chain]]. I hope that's it! [[User:Michael D. Turnbull|Mike Turnbull]] ([[User talk:Michael D. Turnbull|talk]]) 16:05, 2 May 2025 (UTC)
Having a look at the teamdesk thing, too. Thanks [[User:Lukas.S|Lukas]] 01:51, 2 February 2007 (UTC)
::Thank you for contribution. Unfortunately, "[[kinematic chain]]" is not the article I was looking for. [[User:Cerebrality|Cerebrality]] ([[User talk:Cerebrality|talk]]) 00:30, 3 May 2025 (UTC)
:::Perhaps [[Dynamic substructuring]]? The [[Udwadia–Kalaba formulation]] can also be used to derive the equations of motion of a system of connected bodies, but I'm not sure this can be used for bodies connected by strings. ​‑‑[[User talk:Lambiam#top|Lambiam]] 09:06, 3 May 2025 (UTC)
::::Thank you for contribution. Unfortunately, while interesting, this is not the article I was looking for. [[User:Cerebrality|Cerebrality]] ([[User talk:Cerebrality|talk]]) 14:06, 3 May 2025 (UTC)
= May 3 =
:Many computer science types make a hefty profit handling other people's databases, because to even this day it gets messy and application-specific. Though numerous utilities exist ([[MySQL]], MS Access, etc) which supposedly make managing data "simple(r)", I don't know of any that make the solution "user-friendly" to an inexperienced operator. It may be worth paying a fee to an outside service provider, or hire an undergraduate CS intern, if you are unable to develop a complete solution on your own. [[User:Nimur|Nimur]] 08:11, 2 February 2007 (UTC)
== Squidrelativistic Brains and CNS?projectile ==
I'm reading a story in which (among other things) someone is trying to build a gun that shoots 1.5kg iron slugs (5cm diameter) at 60% of the speed of light, for use in space combat.
Hello all!
1) How do I calculate the kinetic energy of the slug? Do I just use <math>E/\sqrt{1-0.6^2}=E/0.8=1.25E</math> where E is the Newtonian approximation? I think that is about as much energy as a 7MT nuclear bomb, if that matters.
I was talking to a friend recently who said that he couldn't understand how it worked, not being scientifically oriented, but that while in Japan he had been told that the liquid he was eating was squid brain, and that it was a liquid. This puzzled us both, as I, too, have not studied marine biology in great depth. Any idea if a) the brain really is liquid, and b) if so, how does the nervous system of a squid work? I know they are invertebrates, but that's about it. The [[Squid]] article doesn't seem to reap much information. [[User:67.174.211.89|67.174.211.89]] 05:57, 1 February 2007 (UTC)
:And hello to you too. Your brain is about 60% water, and can be liquified in a blender and is considered a gastronomic delicacy on R'tyrovkv in the Betegeuse system (lucky for us they are so far away). The unique thing about squid neurons from a neurophysiologist's point of view is that the individual axons are unusually large and were heavily used in the 1960s-80s to study depolarization and potential propagation. They work basically the same way your neurons work. [[User:Alteripse|alteripse]] 10:45, 1 February 2007 (UTC)
:Some more info is at [[Squid giant axon]]. --[[User:Diberri|David Iberri]] ([[User talk:Diberri|talk]]) 18:04, 1 February 2007 (UTC)
::On the brain into a liquid tangent, ancient Egyptians removed the brains in their [[mummification]] process by sticking a flexible tube up their nose and jiggling it several times to turn it into a mush, which was easily extracted from the cadaver from the nostril. '''''[[User:Bibliomaniac15|<font color="black">bibliomaniac</font>]][[User talk:Bibliomaniac15|<font color="red">1</font>]][[Special:Contributions/Bibliomaniac15|<font color="blue">5</font>]]''''' 01:45, 2 February 2007 (UTC)
:::The brains of squids, like all other invertebrates, lack a [[myelin]] sheath. Not sure if this would affect the taste or texture of the brain from a culinary perspective however. [[User:Mikmd|Mikmd]] 17:55, 5 February 2007 (UTC)
:::After reading the myelin article, and the references, it seems that squids may have some form of myelin after all. However, it seems to have evolved independently from vertebrate myelin. [[User:Mikmd|Mikmd]] 18:05, 5 February 2007 (UTC)
2) What happens if the slug actually hits a spaceship? Would it most likely just punch a hole all the way through, without slowing down much? Assuming a large enough ship to self-seal around the holes, is that all that effective a weapon? I.e. the ship is USS Enterprise size or larger.
Thanks. [[Special:Contributions/2601:644:8581:75B0:3DAF:465A:7AA1:65A0|2601:644:8581:75B0:3DAF:465A:7AA1:65A0]] ([[User talk:2601:644:8581:75B0:3DAF:465A:7AA1:65A0|talk]]) 04:04, 3 May 2025 (UTC)
:::I'd never heard of a "squid brain paste" food here in Japan so I looked it up, and the only thing I can find close is [[shiokara]]. It IS a liquid of sorts, but as far as I know there is no variety that is purely made of squid brains (though the brains are most certainly included with the rest of the pureed, fermented squid). [[User:Freshgavin|<font size="-2" color="white" style="background:blue"> freshofftheufo</font>]][[User_talk:Freshgavin|<font size="-2" color="blue">ΓΛĿЌ </font>]] 05:18, 2 February 2007 (UTC)
:The article [[Railgun]] may be helpful.-[[User:Gadfium|Gadfium]] ([[User talk:Gadfium|talk]]) 04:30, 3 May 2025 (UTC)
:The total energy is <math>\frac{m c^2}{\sqrt{1-\frac{v^2}{c^2}}}</math>. Subtract from it the rest energy <math>m c^2</math>. See [[kinetic energy]] (there is a section on the relativistic generalization). [[User:Icek~enwiki|Icek~enwiki]] ([[User talk:Icek~enwiki|talk]]) 06:12, 3 May 2025 (UTC)
== Top 10 Engineering Projects With The Most Human Fatalities? ==
::Using the [[Lorentz factor]]
:::<math>\gamma=\frac1{\sqrt{1-\frac{v^2}{c^2}}},</math>
::this difference can be written compactly as <math>E_\text{kin} =(\gamma-1)\,mc^2.</math>
::When <math>v=0.6\,c,</math> we have <math>\gamma-1=0.25.</math> The energy required to get the projectile up to speed is at least equal to the kinetic energy it gains, about 33.7 [[Metric prefix#List of SI prefixes|P]][[Joule|J]]. For comparison, the energy released by the [[Trinity (nuclear test)|Trinity nuclear test]] was about 0.1 PJ. BTW, the material composition of the slug is immaterial; it might as well be a canister of elderberry preserve. ​‑‑[[User talk:Lambiam#top|Lambiam]] 08:39, 3 May 2025 (UTC)
:That would depend on the spaceship. Is the hull made of unobtanium? Are there shields of some sort? [[User:Clarityfiend|Clarityfiend]] ([[User talk:Clarityfiend|talk]]) 11:07, 3 May 2025 (UTC)
Hello wikipedians,
:At this speed each iron nucleus will have energy of about 15 GeV, which will absorbed by the material the hull is made of. This with result into fireball of high temperature plasma exploding inside the ship. [[User:Ruslik0|Ruslik]]_[[User Talk:Ruslik0|<span style="color:red">Zero</span>]] 20:07, 4 May 2025 (UTC)
::Hmm, will it, though? This isn't a single nucleus; it's a big ol' hunk o' metal. The spaceship atoms in the way of the slug atoms are going to be getting out of the way in a hurry. How much they interact with the rear portion of the slug strikes me as a fairly difficult simulation problem that depends on a lot of details that haven't been specified, but I can imagine a fair portion of the energy being carried out the other side of the spaceship, still as kinetic energy.
::I certainly agree that it isn't going to be good for the spaceship, but if the question is whether we're wasting energy that isn't going into the kill, I don't think we can answer that with the information given. --[[User:Trovatore|Trovatore]] ([[User talk:Trovatore|talk]]) 20:27, 4 May 2025 (UTC)
Thanks everyone. Yes the ships have deflector shields that use antigravity generators of some kind, which is why such fast projectiles are needed. The shields can handle the impacts at 0.1c which is why they are working on getting the speed up to 0.6c. If the defector shield means the slug's energy is transferred to the shield though, that's probably worse than just punching a hole in the ship and coming out the other side. [[Special:Contributions/2601:644:8581:75B0:C710:F116:861:28C5|2601:644:8581:75B0:C710:F116:861:28C5]] ([[User talk:2601:644:8581:75B0:C710:F116:861:28C5|talk]]) 09:30, 5 May 2025 (UTC)
My brother in law and I were discussing the top 10 human engineering projects with the most fatalities. So far we have come up with the [[Death Railway]] (116,000 deaths of workers) and the [[Panama_Canal]] (27,500 deaths of workers).
:Hmm, I wonder whether the articles [[Stopping power]] and [[Terminal ballistics]] might be of any use to answer your question? [[Special:Contributions/2601:646:8082:BA0:C887:6F01:C269:367F|2601:646:8082:BA0:C887:6F01:C269:367F]] ([[User talk:2601:646:8082:BA0:C887:6F01:C269:367F|talk]]) 13:07, 5 May 2025 (UTC)
== Why is GP-A not on [[:File:Time_Dilation_vs_Orbital_Height.png]] total time dilation curve? ==
What other engineering projects would be in the top 10?
(CC:{{ping|Prokaryotic Caspase Homolog}})
Incomplete or unfinished projects are fine.
[[File:Time_Dilation_vs_Orbital_Height.png|thumb|upright=2|Time dilation as a function of orbital height relative to a stationary observer on Earth]]
In the attached thumbnail, ''GP-A'' which is presumably [[Gravity Probe A]] is placed on the ''gravitaional time dilation'' graph instead of the ''total time dilation'' one like the others. Is there a reason for it? Thanks, '''[[User:cmglee|cmɢʟee]]'''⎆[[User_Talk:cmglee|τaʟκ]] 22:33, 3 May 2025 (UTC)
:GP-A did not orbit. It was launched nearly vertically, reached 10,000 km, and came back down. —[[User:Amble|Amble]] ([[User talk:Amble|talk]]) 02:54, 4 May 2025 (UTC)
::Thanks. That explains it. Cheers, '''[[User:cmglee|cmɢʟee]]'''⎆[[User_Talk:cmglee|τaʟκ]] 19:13, 4 May 2025 (UTC)
= May 6 =
We are more interested in projects that have fairly specific numbers. For example, we know that lots of people died making the pyramids of Egypt but for obvious reasons we will never really know even approximate figures.
Thanks in advance,
[[User:Kategorian|Kategorian]] 11:21, 1 February 2007 (UTC)
:Interesting question. I suppose one would have to look at the oldest major engineering works, such as dams and canals. Searching Wikipedia for "workers died" suggests that 120,000 people died during construction of the [[Suez Canal]], and 80,000 during the building of "the British railtrack" in Egypt.--[[User:Shantavira|Shantavira]] 11:55, 1 February 2007 (UTC)
:Chinese urban myth claims that thousands upon thousands of people died while building the Great Wall. There are songs and stories that claim human meat and bone was used for the mortar. However, those horror stories have very little evidence to back them up. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 12:52, 1 February 2007 (UTC)
:You might also look into massive modern works produced in socialist countries in the 1940s and 1950s. I don't know whether many workers died in the construction of the dam on the [[Dnieper river]], for example, or [[Magnetogorsk]], but I would be surprised if they were bloodless, having been constructed with Gulag labor. --[[User:24.147.86.187|24.147.86.187]] 12:59, 1 February 2007 (UTC)
:The [[Trans-Siberian railroad]] has to be a candidate. [[User:Clarityfiend|Clarityfiend]] 15:56, 1 February 2007 (UTC)
::The production of military goods for the German army in WW2 should count as an engineering project, and very many imprisoned workers died in it, including death camp inmates and persons from occupied countries. China's [[Great Leap Forward]] was an engineering program to make China into a leading industrial country. It took a great many lives: villagers were told to make steel in little backyard furnaces by burning their doors and furniture and all trees as fuel, and all they managed was to convert their plows and pots into lumps of molten iron. The harvests were neglected, and in a pretense that agricultural yields had increased, the actual small harvests wer seized for export. The death toll is stated in the article as 14 to 43 million excess deaths. [[User:Edison|Edison]] 17:12, 1 February 2007 (UTC)
Among single construction projects in modern times, the [[White Sea-Baltic Canal]] has to rank pretty high.--[[User:Rallette|Rallette]] 17:55, 1 February 2007 (UTC)
== Cigarette lighters ==
why cigarrette lighter cant be lit by smouldering cigarette? <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:221.134.57.69|221.134.57.69]] ([[User talk:221.134.57.69|talk]] • [[Special:Contributions/221.134.57.69|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned --> (Arun singh Bagh)
:Basicalliy it seems that smouldering cigarrete is not hot enought to rase the gas temp above the critical temerature. See [[flash point]] for some info on this.--[[User:Light current|Light current]] 16:44, 1 February 2007 (UTC)
::There was an episode of [[MythBusters]] where they featured a popular Hollywood myth, that dropping a lit (smoldering) cigarette into a pool of gasoline could ignite it. They were never able to make it happen, but deemed it plausible because the temperature of the cigarette was hotter than the flash point of gas so it "could" happen. I've also heard of anecdotes of people putting out cigarettes in jet fuel (similar to kerosene or diesel). [[User:Atropos235|Atropos235]] 18:25, 1 February 2007 (UTC)
:::Yep - the lighter hydrocarbons are always easier to light - lighter gas is propane or butane, the flash point increases with molecular mass. And yes kerosene and diesel are difficult to light, especially diesel - you ever need a [[wick]] or otherwise it helps if you heat it in a frying pan first until it starts smoldering - then it lights easily..
::Plus a straight cigarette contains significant amounts of nitrate to get sudden flashes of high temperature as the tobacco impregnated with the nitrate burns - these are like little sparks and help ignite things. A 'roll your own' cigarette doesn't have this nitrate and burns much colder and is less likely to ignite a lighter flame - in general they don't..[[User:87.102.77.95|87.102.77.95]] 19:30, 1 February 2007 (UTC)
== Sodium vapour lamps ==
why sodium vapour lamps are used for street lights? <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:221.134.57.69|221.134.57.69]] ([[User talk:221.134.57.69|talk]] • [[Special:Contributions/221.134.57.69|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned --> (Arun singh Bagh)
:The most amount of light for the least amount of electricity. See [[Sodium vapor lamp]].
:[[User:Atlant|Atlant]] 16:14, 1 February 2007 (UTC)
:High [[efficacy]]?--[[User:Light current|Light current]] 16:37, 1 February 2007 (UTC)
::From a desire to make everything look yellowish with monochromatic 590 nm illumination, to make the skies over cities look orange, or to save electricity. [[User:Edison|Edison]] 17:15, 1 February 2007 (UTC)
::its gotta be efficacy. If someone invented a higher efficacy green light, our night skies would turn green.--[[User:Light current|Light current]] 18:33, 1 February 2007 (UTC)
One consideration is that low-pressure sodium-vapor lamps are good for astronomers, because their [[light pollution]] can easily be filtered out (that's because they're so nearly monochromatic; you just have to block that one single line). In my opinion they're also less ugly than high-pressure sodium-vapor lamps (those are the pink ones). --[[User:Trovatore|Trovatore]] 18:37, 1 February 2007 (UTC)
It's what we already have, and would cost too much to replace all of them:)[[User:Hidden secret 7|Hidden secret 7]] 19:40, 1 February 2007 (UTC)
[[Image:HLR-OSRAM-3KW-B.jpg|thumb|Xenon arc lamp]]
:New lamps can vary greatly. I've seen several recently which look to be high-intensity fluorescent lights (sort of like the [[Compact_fluorescent_light_bulb soft-glow lightbulb]]s. And of course [[xenon arc lamp]]s are used, especially on high traffic highways.
::Sorry, no. A variation on xenon arc lamps may be in your car's [[headlamp]]s, but they're not used for overhead lighting on highways (because sodium vapo[u]r lighting is so much more efficacious).
::[[User:Atlant|Atlant]] 14:10, 2 February 2007 (UTC)
==Chlorophyll efficiency==
Is there some reason why the green part of the visible spectrum is not absorbed by chlorophyll and associated pigments? Why is chlorophyll able to absorb only red and blue light? Would a more efficient system absorb all visible light? {{unsigned|220.236.73.126}}
:I'm not sure, but at a guess I would say that plants just doesn't need to. They get sufficient energy from the wavelengths that they do absorb. Also, if plants were absorbing all wavelengths in the visible spectrum, they would probably overheat. (And who wants a world full of black plants anyway?) [[User:BenC7|BenC7]] 07:14, 2 February 2007 (UTC)
:: I think the best way to explain this is that "nature" didn't just engineer the optimum system. It evolved this way, probably based on prior chemical reactions. I'm not entirely sure how the chemical reaction operates, but it very likely cannot use any arbitrary energy, requiring specific frequencies to serve as [[activation energy]] for chemical changes. [[User:Nimur|Nimur]] 08:22, 2 February 2007 (UTC)
*Chlorophyll is green. The reason we can observe that is because it doesn't get absorbed. If it did, it wouldn't be green anymore. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 11:09, 2 February 2007 (UTC)
Don't some plants already have black leaves
== Body Changes ==
I am not sure how to phrase this correctly nor have the proper terminology, but my question is:Is it possible that your genetic makeup can change throughout your life. When I was a child, I remember having very straight hair and I longed for curly hair. However, in my early 20's, my hair became very thick and curly. Now, I am in my mid 30's and my hair changing it's structure again. It is becoming straighter. Any ideas?
:It is ''not'' possible for your genetic makeup to change (aside from random DNA mutation that would likely only result in damaged or cancerous individual cell populations). There are many reasons why your hair might be changing structure, including age, changes in diet, or moving to a different climate. It's not at the DNA level. -- [[User:Scientizzle|Scientizzle]] 16:28, 1 February 2007 (UTC)
:: This is probably common knowledge to anyone who has taken high school biology, but I couldn't locate anything in [[DNA|our article on DNA]] that says as much. [[User:Vranak|Vranak]]
:It is hard to believe that the dramatic changes of my hair structure was from what I ate or where I lived.Please understand that I had pin straight hair (similar to Asian hair) when I was 8 but by the time I was 21, it was very thick and curly...
::Though I've never heard of what you describe specifically, hair does respond in a variety of way to the levels of certain hormones that increase during [[puberty]]/maturation and fall off during middle age.See [[Hair#Growth]].[[User:Dragons flight|Dragons flight]] 17:46, 1 February 2007 (UTC)
It isn't just puberty, my hair has been getting darker from light blond to a very dark brown at least since I was born:)[[User:Hidden secret 7|Hidden secret 7]] 19:44, 1 February 2007 (UTC)
:It's very common for light hair to get darker through childhood - lots of kids are born with blond hair but don't keep it - blond kids are usually born with very white hair. I don't know if this means you will go platinum in later years or not. It's common in the animal world for juveniles to have a different colouration to adults.[[User:87.102.77.95|87.102.77.95]] 19:56, 1 February 2007 (UTC)
:As for your hair changing from curly to straight again - don't know.[[User:87.102.77.95|87.102.77.95]] 19:58, 1 February 2007 (UTC)
:I always thought it was strange that my hair behaved this way.Someone mentioned that our skin(?) completely changes every 7 years and maybe so with hair texture.Maybe I am not human!
I don't think I am either:)[[User:Hidden secret 7|Hidden secret 7]] 20:50, 1 February 2007 (UTC)
::There is one important exception to the rule that your DNA doesn't change during life, which applies to cells of the immune system, i.e. [[B lymphocytes]] and [[T lymphocytes]]. During maturation, the DNA coding for these cells' receptors is rearranged, see [[VDJ recombination]]. The changed DNA is inherited by daughter cells. The rearrangement occurs in a random fashion, and because various fragments are involved, each of which comes in a large number of variants, combinatorics ensures that the number of different receptors is formidable. In addition, there are enzymes that insert non-coded nucleotides at the points where the DNA is spliced. The potential number of antigen receptors is enormous. Lymphocytes which encounter antigens that happen to match their receptors, are selected in a Darwinian manner. This is the basis of immunization - somatic DNA recombination is the reason why we are able to make antibodies against such an enormous number of pathogens. The fact that the receptors aren't "hard-coded" makes this a very flexible system, which can adapt to new threats. To my knowledge, it is the only known example of somatic DNA recombination in vertebrates. --[[User:NorwegianBlue|NorwegianBlue]]<sup>[[User_talk:NorwegianBlue| <u>talk</u>]]</sup> 20:56, 1 February 2007 (UTC)
:::Only known example, except of course [[Oncogene|somatic mutations that lead to cancer]]. --[[User:NorwegianBlue|NorwegianBlue]]<sup>[[User_talk:NorwegianBlue| <u>talk</u>]]</sup> 21:03, 1 February 2007 (UTC)
In your comment NorwegianBlue,"The rearrangement occurs in a random fashion, and because various fragments are involved, each of which comes in a large number of variants, combinatorics assures that the number of combinations is formidable", are you saying as our DNA changes during maturation for immunizations against pathogens, this possibly can affect hair texture, iris color, etc?I also know of an African-American person who also experienced the same issue as well...
:No. This process only applies to the genes coding for the [[T cell receptor]] and the [[Immunoglobulin|B cell receptor (immunoglobulin)]], and "maturation" refers to the maturation of the individual cell. --[[User:NorwegianBlue|NorwegianBlue]]<sup>[[User_talk:NorwegianBlue| <u>talk</u>]]</sup> 21:03, 1 February 2007 (UTC)
::Think of your hair changes similar to how your body changes when you go through puberty. When you hit puberty, you grow facial hair, get bigger & stronger & grow an adam's apple etc. This is not your DNA changing, but instead hormones & internal changes stirred by chemicals. Your body can change drastically without warning. Keep in mind however, that indeed DNA can affect whether we do have curly or straight hair, but changing between the two isn't unheard of either. Many children may have curly or straight hair in childhood & then have the opposite later in life. When babies are born, they may have a different eye colour to later on in life & so on & so on. Your DNA does not change unless you're one of the X men. Hope this explains it easily... [[User:Spawn Man|Spawn Man]] 21:45, 1 February 2007 (UTC)
:::And if you're interested in whats going on on the molecular, level, you might want to read the article [[regulation of gene expression]]. --[[User:NorwegianBlue|NorwegianBlue]]<sup>[[User_talk:NorwegianBlue| <u>talk</u>]]</sup> 08:45, 2 February 2007 (UTC)
:I also experience this. When I was little, I had curly, thick blonde hair. Later my hair became really straight and black, and now my hair is this dark brown, but it's really curly and somewhat thick. All this happened in 16 years of my existence. I have a question, if it's not possible for your genes to change, where does evolution happen? Surely your genes have to change. <b><FONT FACE="MS Reference Sans Serif" COLOR="#FF0000">► [[User:Adriaan90|Adriaan90]] ( [[User Talk:Adriaan90|Talk]] ♥ [[Special:Contributions/Adriaan90|Contribs]] ) ♪♫</FONT></b> 13:30, 5 February 2007 (UTC)
::There are in fact [[mutation]]s and [[genetic recombination]]s, and even [[DNA repair]], but there are no deliberate, routine, permanent changes to DNA made by any organism. (The [[self-modifying code|result]] would be very hard to do safely, after all.) Evolution is a result of the accumulated random changes to DNA inherited by offspring. See, however, the current field of genetics research dealing with [[promoter]]s and company, which do not modify DNA but have much the same effect by dynamically affecting how it is used. --[[User:Tardis|Tardis]] 19:15, 5 February 2007 (UTC)
== If you tied a rope around the moon and let the other end hang down onto the surface of the earth... ==
1)When the moon moved, would the rope drag across the surface of the earth, and if so how fast? 2)And if not, would it go out into space and trail behind the moon or what would it do? The gravity field of the earth and the moon are significantly less than the amount of empty space in between the earth and the moon. 3)If the answer to the first question is no, could you hold onto the rope as it pulled you up into the sky? 4)How much weight would it take to keep the rope vertical to the earth? 5)Would that amount of weight cause the moon to stop moving and come crashing down onto the earth?
This will be a big help for one of the questions on my thirty-problem physics project, thanks! [[User:Xhin|Xhin]] 16:47, 1 February 2007 (UTC)
:(numbered the questions to make responses easier). During a single night, the earth's rotation makes the moon appear to move across the sky. Per [[Moon]] the Moon makes one complete orbit about the Earth every 27.3 days. The nearest point to the moon on the earth's surface makes a revolution every day, with adjustment for the moons 27.3 day cycle. What does that suggest about the rope staying at one point? Per [[Earth]] the planet's mean circumference is 40,041.47 km, and its sidereal rotation period is 0.997 258 d (23.934 h). Earth's rotation velocity at the equator is 465.11 m/s or 1040 miles per hour, which has to be adjusted plus or minus for the moon's travel around the earth.The question implies that the rope starts on the earth's surface. The statement "The gravity field of the earth and the moon are significantly less than the amount of empty space in between the earth and the moon." makes a meaningless comparison between gravity and space. How can gravity be less THAN space. Did the question originally say IN space? I suggest the hypothetical rope would have to be extremely strong and perhaps fireproof. I suggest that no amount of weight could keep it absolutely vertical to the earth, but the deflection from passage through the atmosphere would be a difficult calculation depending on air resistance, which would depend on the diameter and surface of the rope, and more complex because it would change with altitude. [[User:Edison|Edison]] 17:31, 1 February 2007 (UTC)
::The question would be interesting if rephrased for a sitution where ''both'' bodies are [[tidally locked]] with respect to each other (eg. [[Pluto]] and [[Charon]]). What stresses would be suffered by a [[space elevator]] linking these two bodies? [[User:Carcharoth|Carcharoth]] 18:01, 1 February 2007 (UTC)
You should note the difference between the [[apogee]] and [[perigee]] of the moon's orbit.—[[User:EricR|eric]] 18:12, 1 February 2007 (UTC)
:Well I've come up with a simple answer to your question. All the roads in New Zealand, lined back to back, would make it 3 quarters of the way to the moon. Now all you have to do is measure all the roads in New Zealand & then do the math. ;) [[User:Spawn Man|Spawn Man]] 21:49, 1 February 2007 (UTC). P.S. The rope might catch on a rock & send the moon crashing down in the Atlantic, so be sure you use duel fibre twine... ;)
To question 1, I think yes. The rope would be close to vertical most of the way, but once it hits the Earth's atmosphere, the atmospheric drag will push it forward (since the Earth rotates faster than the moon orbits), so it will be slanted at an angle near the surface of the Earth. To question 4 (if I understand what you mean), that is impossible, because the atmospheric drag pushes the rope forwards, and if were vertical, there would be no force to oppose it going the other way. --[[User:Spoon!|Spoon!]] 23:55, 1 February 2007 (UTC)
== Why Don't They Send Hubble's Twin in Orbit? ==
When they constructed the Hubble telescope two decades ago, all key components were manufactured in pairs (in case one breaks down, the redundant component is available right away). Now that the one currently in operation is approaching its end of life--and that another shuttle repair mission will cost a fortune--why don't they just put all the spare parts together and launch the thing up there? The twin may not be the latest technology, but it sure could be a cheaper way to get a new telescope in orbit, serving science for the next two decades.--[[User:JLdesAlpins|JLdesAlpins]] 17:23, 1 February 2007 (UTC)
:Is there evidence they made a second mirror? At the time of its making, there was an article about how expensive it was, and that it was the best mirror ever built. Later it turned out they had totally botched the fabrication and testing and the thing had to have corrective lenses added. Have some of the spares been used on the repair missions? An unanswered question is how similar the general optics of spy satellites are to those of Hubble. They are supposed to have amazing resolution, but would lack some of the aiming ability and some of the special astronomical optics. [[User:Edison|Edison]] 17:38, 1 February 2007 (UTC)
::One of the largest differences between an earth-observing satellite and the Hubble is the amount of light collection area and maybe to a lesser extent the ability to keep attitude very precisely.Images like the [[Hubble Deep Field]] require an ''extremely'' long exposure time, even with the Hubble's large mirror.Images like [http://antwrp.gsfc.nasa.gov/apod/ap061228.html] also show what vistas large amounts of light gathering area can give you.Like spy satellites, you or I can easily see things on Earth because they're illuminated so well, could never see anything like that with our pair of 1x 1-cm refractors. [[User:Atropos235|Atropos235]] 18:03, 1 February 2007 (UTC)
::See [[Hubble Space Telescope#Optical Telescope Assembly (OTA)]] for information about the second mirror. --[[User:CesarB|cesarb]] 18:30, 1 February 2007 (UTC)
:Hubble was designed to be orbited in the carbo bay of the [[space shuttle]].Given that you'd have to launch a shuttle either way, it is unlikely that there would be much cost savings.[[User:Dragons flight|Dragons flight]] 17:42, 1 February 2007 (UTC)
Lets not forget the cost to acctually form the second hubble. putting the spare parts together will still require extreamly skilled scientest to put it together and many months to do it right [[User:Maverick423|Maverick423]] 17:51, 1 February 2007 (UTC)
::And lets not forget, the spare parts were there in case something goes wrong, so imagine something went wrong while assembling the spare parts, they'd have no redundancy.[[User:Vespine|Vespine]] 21:32, 1 February 2007 (UTC)
:Hubble's "dubble"? [[User:Clarityfiend|Clarityfiend]] 01:20, 2 February 2007 (UTC)
:OK, suppose that everything on Hubble was duplicated - Hubble has been serviced a couple of times since launch - might some of those duplicate "spares" have been used up in servicing it? [[User:Richard B|Richard B]] 01:31, 2 February 2007 (UTC)
I think it's probably an engineering exaggeration to say "everything" was doubled; furthermore, the likelihood that all parts are carefully cataloged, stored in one warehouse, with blueprints and assembly instructions is virtually zero.Significant engineering effort would be needed; and even the original engineers probably don't even remember all of the design properties.It is probably easier and cheaper to start from scratch.After all, the most expensive part of spaceflight systems is very rarely the actual components costs. [[User:Nimur|Nimur]] 08:29, 2 February 2007 (UTC)
== Narcotics ==
Is there any type of narcotic drugs that include [[iodine]] atoms in the molecule? [[User:TERdON|TERdON]] 18:07, 1 February 2007 (UTC)
:The simple answer is yes - but they are not common. Iodine (and also other halogens chlorine, bromine and fluorine) is sometimes incorporated into the basic drug structure - one of the main reasons this is done is that the resultant compound is easier to absorb through the gut walls as it is more 'fatty'.
:(also Iodinated and brominated 'ecstacy' derivatives are found often enough to be called common, I'm not sure that amphetamines are classed as narcotics though.)
:I don't have enough knowledge to say if there are any drugs of this type in common use.[[User:87.102.77.95|87.102.77.95]] 19:23, 1 February 2007 (UTC)
::In Sweden, no doubt amphetamine is illegal, I suppose the same holds true of its derivates. Thanks for the answer! :) [[User:TERdON|TERdON]] 20:18, 1 February 2007 (UTC)
:::I don't think amphetamine is a narcotic (narcotics are derivatives of opium), but perhaps you meant [[psychoactive drug]]? − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 22:13, 1 February 2007 (UTC)
::::I didn't mean they were narcotics by the ''scientific'' definition, but by the Swedish ''legal'' definition, which includes all kinds of addictive drugs that aren't, technically, narcotics. [[User:TERdON|TERdON]] 22:18, 1 February 2007 (UTC)
: Yes, "crack," but it's not in the narcotic.Instead it's part of the precursors, see [http://www.justice.gov/ndic/pubs1/1467/index.htm Iodine in Methamphetamine production.]As part of the "war on drugs," some states in the USA require that iodine suppliers record and retain customer information on anyone buying iodine. --[[User:Wjbeaty|Wjbeaty]] 20:42, 1 February 2007 (UTC)
== Source ==
Is <strike>their</strike> there enough kinetic energy in a human body to move an object?{{unsigned|71.201.233.107}}
:People move things every day - I'm not sure what else you could be asking? please explain..[[User:87.102.77.95|87.102.77.95]] 19:15, 1 February 2007 (UTC)
Do you know what [[kinetic energy]] is?It's the energy of a [[mass]] in motion.One way to tell that an object in motion has kinetic energy is to watch what happens when the object [[collision|hits]] another object: in a collision, one moving object can [[conservation of energy|impart]] kinetic energy to the collided-with object, causing the collided-with object to move as well.Does this answer your question? --[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 19:19, 1 February 2007 (UTC)
are you trying to talk about [[telekinetic energy]]? which is more of a phycic power then anything. [[User:Maverick423|Maverick423]] 21:09, 1 February 2007 (UTC)
:See [[Psychokinesis]]. I would have to answer "No, there is not enough psychokinetic/telekinetic energy in a human body to move anything." But I have an open mind and would be ready to be proven wrong. There are many ways to fake it or to think it is observed in poorly controlled experiments. [[User:Edison|Edison]] 21:30, 1 February 2007 (UTC)
::There's often just enough to move money from a believer's wallet/purse to the claimant's. Spooky! [[User:Clarityfiend|Clarityfiend]] 21:53, 1 February 2007 (UTC)
It might just be that things that can be moved like this are too small to see:)[[User:Hidden secret 7|Hidden secret 7]] 20:47, 3 February 2007 (UTC)
: To move an object with the kinetic energy of a human, you would need to have the human collide with the object.Imagine body-slamming a box.Then, your kinetic energy would (partially) transfer and the box would jolt forward.Perhaps you mean [[potential energy]] which may be stored in the muscles in chemical form ([[adenosine triphosphate]])?This can be converted into kinetic energy, (probably also generating thermal energy and other forms...) allowing the muscle to move an object. [[User:Nimur|Nimur]] 08:32, 2 February 2007 (UTC)
:: Hah.I'm now having hilarious visions of ragdoll-physics style "human collisions" to test the inelasticity of collisions.Efficient transfer of kinetic energy from the human to the object is almost as much fun as inefficient transfer. [[User:Nimur|Nimur]] 08:34, 2 February 2007 (UTC)
== High density polyethylene ==
Hello, does anyone know of a supplier for blocks of high density polyethylene.I'm looking for a small cube of the stuff that I can mill down a little bit.
:Try [http://www.mcmaster.com McMaster-Carr]. [[user:anonymous6494|anonymous6494]] 20:55, 1 February 2007 (UTC)
:Isnt [[polyethylene]] always the same density? --[[User:Light current|Light current]] 01:36, 2 February 2007 (UTC)
::No. See [[HDPE]] vs [[LDPE]]. [[User:DMacks|DMacks]] 02:46, 2 February 2007 (UTC)
== Water on Mars ==
is there really water in Mars?–––Thanks
:There is no doubt about the presence of [[water]] on [[Mars]]. A more intriguing question is whether or not there is '''liquid''' water on Mars, and [[Mars#Possibility_of_liquid_water|recent evidence]] has been pointing towards a positive answer. — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 00:29, 2 February 2007 (UTC)
== Lava and Magma ==
Which is thinner, magma or lava?
:same stuff I thought!--[[User:Light current|Light current]] 01:32, 2 February 2007 (UTC)
:Well according to [[She_Used_to_Be_My_Girl|Chloe Talbot]] from [[The Simpsons]], [[magma]] is the word for [[lava]] when it's underground. Which would mean that lava would be more [[viscous]], but magma would be denser. [[User:Anchoress|Anchoress]] 01:42, 2 February 2007 (UTC)
::<s>No no</s> Yes. [[Lava]] is magma when its under ground.When its [[erupt]]ed its [[lava]]. [[Pumice]]--[[User:Light current|Light current]] 02:28, 2 February 2007 (UTC)
:::That's what [[User:Anchoress|Anchoress]] said. =) [[User:Chickenflicker|Chickenflicker]]---[[User talk:Chickenflicker|♣]] 04:33, 2 February 2007 (UTC)
:::Quire rite sorry. It was the Simpsons who put me off.8-)--[[User:Light current|Light current]] 11:45, 2 February 2007 (UTC)
If it had to be one or the other, it would be lava; but not by much, I would imagine. As the molten rock comes closer to the surface it experiences less pressure and presumably expands, making it less dense or "thinner". I'm not sure, however, the degree to which it would expand, or if that would be significant to appropriately label it "thinner". [[User:BenC7|BenC7]] 07:22, 2 February 2007 (UTC)
:If lava can be approximated as an [[compression|uncompressable]] [[fluid]], the pressure change would have little effect on the density.One thing that does significantly affect density is [[silica]] content.Hawaiian volcano lava is quite different from, say, Mount Saint Helens (which has more silica, is more dense, and thus exploded violently!)Hawaiian lava flows gracefully with much less exploding. [[User:Nimur|Nimur]] 08:37, 2 February 2007 (UTC)
::(comment) doesn't the explosiveness of magma relate to the amount of dissolved gas in it (eg water) - that is released when the pressure vessel that is the inner volcano is opened..(or does silica rich magma have greater ability to hold gases???)[[User:87.102.4.6|87.102.4.6]] 11:55, 2 February 2007 (UTC)
I <s>too</s> would expect [[lava]] to be <s>thinner</s> thicker (<s>less</s> more [[viscous]]) than [[magma]] since it is '''cooler'''. I don't know how pressure affects viscosity. Reading both articles it explains that the viscosity depends on the composition - so there may not be a definative answer.[[User:87.102.4.6|87.102.4.6]] 10:33, 2 February 2007 (UTC)
:Both lava and magma is made of all types of substances, and are all different temperatures. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 18:09, 2 February 2007 (UTC)
I would have expected lava to be more viscous as it is cooler, since this would mean less kinetic energy for each molecule, and therefore less energy to move them apart:)[[User:Hidden secret 7|Hidden secret 7]] 20:50, 3 February 2007 (UTC)
:Unlike gases, there is no "ideal law" for fluids, let alone an accurate one. Non-ideal effects will dominate what factors determine density. [[User:Nimur|Nimur]] 01:08, 4 February 2007 (UTC)
= February 2 =
== Appendectomy and oxygen ==
Is it normal for a person who has undergone an appendectomy (burst appendix) to be on post operative oxygen?--[[User:Light current|Light current]] 01:31, 2 February 2007 (UTC)
:THis would be for a person abot 70 years old.--[[User:Light current|Light current]] 11:46, 2 February 2007 (UTC)
:I was about 5 when it happened, but I remember them putting tubes down my nose, so I wouldn't think it'd be somewhat normal. It is a potentially fatal thing. --[[User:Wirbelwind|Wirbelwind<small>ヴィルヴェルヴィント</small>]] ([[User_talk:Wirbelwind|talk]]) 03:59, 2 February 2007 (UTC)
:For any procedure involving general anesthesia, and intubation, one can expect to wake up with an oxygen mask on, especially at an advanced age. High oxygen will help a patient overcome the trauma of the surgery, and more important it will help that patient clear infections from the perforation and the surgical insult. <sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .1em .1em .9em .1em;">tucker</font>]]</sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .35em .1em .35em .1em;">/</font>]]<sub>[[User:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .9em .1em .1em .1em;">rekcut</font>]]</sub> 12:11, 2 February 2007 (UTC)
::Ah thank you. Just the ans I wanted!--[[User:Light current|Light current]] 12:12, 2 February 2007 (UTC)
== Best position to land ==
When falling from high up (for example, a fifth storey), what would be the safest position to land when hitting solid ground? --[[User:Codell|<font color="#999933">Codell</font>]] <sup>[ [[User talk:Codell|<font color="#009999">Talk</font>]]]</sup> 02:39, 2 February 2007 (UTC)
:[http://www.wikihow.com/Survive-a-Long-Fall] [http://www.straightdope.com/columns/050311.html] -- [[User:Consumed Crustacean|Consumed Crustacean]] <small>([[User talk:Consumed Crustacean|talk]])</small> 02:43, 2 February 2007 (UTC)
:Dunno if it was ever proven, but I'd always heard if you can somehow pull off a rolling landing, you could possibly survive (height depending of course). [[User:Cyraan|Cyraan]] 02:51, 2 February 2007 (UTC)
Thank you, Consumed Crustacean. This answers my question.--[[User:Codell|<font color="#999933">Codell</font>]] <sup>[ [[User talk:Codell|<font color="#009999">Talk</font>]]]</sup> 03:47, 2 February 2007 (UTC)
as far above the ground as possible
== How to draw: trans-3,5-dibromocyclodecyne? ==
This is the only problem I can't do for my alkyne nomenclature homework.
I submitted the structure, but the program keeps telling me to show the trans configuration of the Br Atoms.But I'm pretty sure I put the Br atoms where they're supposed to be.I'm also sure that I have the cyclodecyne structure right, so it must be something else I'm missing.I tried all combinations of where the Br are located respective of one another.Because it's trans, I'm guessing that one of the Br atom is inside the ring, and the other on the outside.I tried that, but it wasn't correct.Any ideas?Thanks in advance [[User:128.163.214.199|128.163.214.199]] 03:06, 2 February 2007 (UTC)
:By saying "inside" and "outside", you're thinking about the ring and everything attached to it as being flat. Ain't so...visit your textbook chapter about alkanes or [[orbital hybridisation]] to see why things attached to the ring are often described as "above" and/or "below" the plane of the ring, never inside/outside the ring. [[User:DMacks|DMacks]] 03:14, 2 February 2007 (UTC)
::from [[trans]] "A similar phenomenon is seen in cyclic compounds (in which the atoms form a closed ring), where substituents can be on the same "face" of the ring (cis) or opposite faces (trans.)" - so agree with above - it's above or below the plane of the ring.[[User:87.102.4.6|87.102.4.6]] 11:06, 2 February 2007 (UTC)
::[[Geometric isomerism]] has more details, and a diagram for the cycohexane case.[[User:87.102.4.6|87.102.4.6]] 11:07, 2 February 2007 (UTC)
3,5-dibromocyclodecyne is chiral at both the 3 and 5 positions, usually a trans structure refers to atoms on opposite sides of a thing (atom, double bond) - it sounds like you need to know the most stable conformation of the molecule and put the bromines on opposite sides. In actuality the name you've got doesn't seem to be a useful description of the molecule - I'd expect something like R,R 3,5-dibromocyclodecyne, R,S 3,5-dibromocyclodecyne, S,R 3,5-dibromocyclodecyne, S,S 3,5-dibromocyclodecyne.[[User:87.102.4.6|87.102.4.6]] 10:31, 2 February 2007 (UTC)
Thanks a lot, everyone. I misinterpreted the diagram in the book; somehow I didn't look at the type of bond (up/down). Now I understand the concept better.[[User:128.163.224.201|128.163.224.201]] 18:08, 3 February 2007 (UTC)
== Time for Escape!!! ==
How long would it take to accelerate human passengers in a craft to about eight miles per second, and lets say they are traveling at a constant 3g?[[User:67.127.96.131|67.127.96.131]] 03:39, 2 February 2007 (UTC)
:Sorry, but we don't answer homework questions! But to help you out: have a look at the [[acceleration]] article, you'll notice the following equation:
:<math>
\mathbf{\bar{a}} = {\mathbf{v} - \mathbf{u} \over t}
</math>
:Using that, you can find the time required. All the best. - [[User:Akamad|Akamad]] 03:48, 2 February 2007 (UTC)
Oh man thank you someone finally gives me an equation and thank you but this is not homework I am just very curious about these things.[[User:67.127.96.131|67.127.96.131]] 05:19, 2 February 2007 (UTC)
:Yes, I am similarly curious about how long it will take a train leaving Philadelphia traveling at 180 km/h to reach a train that has left New Jersey traveling at 200 km/h. But of course, not for my homework! − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 06:50, 2 February 2007 (UTC)
::Several of the times when I've tried it, [[Amtrak]] or [[New Jersey Transit]] has had equipment failures. Where does that go in the equation?
::[[User:Atlant|Atlant]] 14:04, 2 February 2007 (UTC)
We surely don't want to confuse the questioner, but this equation might be helpful as well.
<math>
x(t) = x_0 + vt + 1/2at^2
</math>
<math>
v(t) = v_0 + at = dx(t)/dt
</math>
[[User:Nimur|Nimur]] 08:42, 2 February 2007 (UTC)
Awesome eqautions but once again it's not homework and believe it or not I haven't ever had a physics class. Someone just please tell me how to plug in the numbers.
:What you want to do is solve the equation (the equation I gave you, the first equation that Nimur gave is for finding displacement, and the second equation is the same as the one I wrote down) for t (the time variable). Here is a link on how to solve equations if you need help: http://www.sosmath.com/algebra/solve/solve0/solve0.html. You already know the final velocity (8 miles/second) and the acceleration (3g). From your question, you can assume the initial velocity to be zero. So all the variables are known. But make sure all your units are the same (for example, you'll have to change the 3g to miles/second/second, have a look at this article: [[Earth's gravity]] for what the "g" means. Hope that helps. - [[User:Akamad|Akamad]] 11:17, 3 February 2007 (UTC)
Okay, I'll assume good faith and give the answer. The simplest form of the relevant equation is just <i>v = at</i>: speed (assuming you start from 0) is acceleration times time. So <i>t = v/a</u>: time is speed divided by acceleration. g is 9.8 m/s², so the acceleration 3g is 29.4 m/s². 8 miles is 12,875 meters, so 8 mi/s = 12875 m/s. So the answer is 12875/29.4 = 438 s (see, dividing the units of m/s² by m/s gives seconds) or 7.3 minutes. I've rounded the numbers along the way since I assume the 8 mi/s was not intended to be an exact number. --Anonymous, February 3, 2007, 22:02 (UTC).
Okay thank you because I did attempt to do the eqaution given to me by Akamad and I ended up with 8.76 hours! The reason why I asked this I wanted to know if the speed could be acheived without killing the passengers. Now the next problem to face is making it through the atmosphere without burning up or the craft loosing velocity. Anyways everyone thank you again.
:Note that real-life space launches achieve orbital velocity of about 5 miles/second without killing the passengers. Achieving 1.6 times the speed could be done by accelerating 1.6 times as long. (In practice the acceleration is not constant, so it's a bit more complicated than that, but that'll do for a rough idea.) --Anon, Feb. 4, 05:05 (UTC).
== Light ==
Greetings,
I have done small studies an have a theory. Light has mass and weight. It must, because a black hole pulls in light. I don't understand the technical jargon.
Please let me know if it has mass. (In layman's terms)
Fare thee Well,
[[User:AlexanderTG|AlexanderTG]] 05:58, 2 February 2007 (UTC)
:What is your theory? This sounds like the [[wave–particle duality]] of [[light]]. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 06:52, 2 February 2007 (UTC)
::[[General Relativity]] is exactly the technical jargon which explains how gravity can "pull" something (like light), even if it has no mass.Some people try to explain this by saying that the gravity bends space and time.It is very well established that light has no mass, and many experiments and equations exist to back this up. [[User:Nimur|Nimur]] 08:44, 2 February 2007 (UTC)
::: You might also consider [http://simple.wikipedia.org/wiki/General_relativity General Relativity] at the [http://simple.wikipedia.org Simplified Wikipedia] if you are having difficulty with technical jargon. [[User:Nimur|Nimur]] 08:46, 2 February 2007 (UTC)
:Also, what do you mean by ''mass''? [[Mass in general relativity]] is very complicated and may not be well defined at all. --[[User:Spoon!|Spoon!]] 09:25, 2 February 2007 (UTC)
:Short answer - light is made up of photons; photons do not have [[rest mass]], but they do have [[relativistic mass]], because they have [[momentum]]. [http://math.ucr.edu/home/baez/physics/Relativity/SR/light_mass.html This article] answers the question "If light has no mass how can it be deflected by the gravity of a star?". [[User:Gandalf61|Gandalf61]] 14:12, 2 February 2007 (UTC)
They say gravity bends space, but the experiment they do to show this where the balls roll toward each other only works because of the earths gravity below it:( Is this because they can't find any real way to show what is happening, and are hoping we don't notice, or am I missing something important here:([[User:Hidden secret 7|Hidden secret 7]] 20:54, 3 February 2007 (UTC)
:You didn't miss anything - the bending thing is bogus. The reason light is attracted to black holes is that is has mass, just like any other particle. True it doesn't have rest mass, but that doesn't make the mass any less real. There is no need to invent bending of space or anything like that. [[User:Ariel.|Ariel.]] 13:19, 4 February 2007 (UTC)
:: Ariel's comments are a simplification which may adversely affect the original questioner's understanding. It is not correct to say that light has mass ''in the conventional sense''. As noted above, in certain treatments of relativity, the semantics of "mass" can be redefined, but this is playing games with human language and word choice. The "bending thing" is another way to work out the equations. After all, [[science]] is just a [[model]] of our universe, not a perfect description. [[User:Nimur|Nimur]] 03:33, 8 February 2007 (UTC)
== donut constellation ==
There seem to be models for ethernet structures described as a donut constellation. The descriptions of the structure are too technical for me to understand. I have heard the term donut constellation used to described the way energy revolves in some physical structures as well. The philosphers Deleuze and Guattari describe social maps and organizations that evolve rhizomatically along a number of axi and levels. As a result many creative and visual thinkers use this structure as an exploratory model. I think the donut constellation whereby energy is constantly revolving on a number of planes around a vacant middle maybe used to as an alternative model for describing the way chunks of the creative thought process evolves. I would like to read more about this type of structure. I think there is a more accurate word, that those versed in physics would use to describe it.
:The word is [[torus]], the surface is represented by a [[quartic equation]] in three dimensional space. As for a doughnut shaped ethernet this would be a ring shaped data bus with various data items branching off it.[[User:87.102.4.6|87.102.4.6]] 10:24, 2 February 2007 (UTC)
== Antagonism vs Inhibition | Enzymes & Neurotransmiters ==
*On the other hand, compounds that inhibit reuptake ''but also inhibit release of dopamine'', such as [[bupropion|Wellbutrin]] and [[vanoxerine]], have mild stimulant effects and little abuse potential, and can be used to treat stimulant addiction. {{fact}}
*[[Olanzapine|Zyprexa]]'s antipsychotic activity is mediated primarily ''by antagonism at [[dopamine]] receptors.''
Scientifically speaking, is there any differece between Antagonism and Inhibition? Please provide references to back up your answer.
''I would appreciate the answers provided. Thnx.'' --[[User:Parker007|Parker007]] 12:37, 28 January 2007 (UTC)
:I'd suggest that the usage choice is a language one, (I can't call a difference between the two). Medical dictionary (is this a good source?) has the two lumped together for the same definition see http://www.wrongdiagnosis.com/medical/inhibitor_antagonist.htm
:The real difference is actually in other usage - an antagonist 'works against' eg pairs of muscles that pull on either side of the bone, an inhibitor prevents the action itself. I'm not sure that in biochemical usage the distinction is made (of perhaps even known).
:Also http://www.thefreedictionary.com/antagonist defines antagonism in a biochemical sense as "Biochemistry A chemical substance that interferes with the physiological action of another, especially by combining with and blocking its nerve receptor" eg as an inhibitor.
:So in biochemistry they seem to have the same meaning - though if more becomes known about the mode of action of a given substance perhaps in the future a distinction will be made.
:Comment on proper usage...
:For instance a compound that causes dopamine uptake is antagonistic to a compound that causes dopamine release - but does not inhibit.
:Whereas a compound that binds to a site causing dopamine release (not activating it) can be called an dopamine release inhibitor. (But may also be decribed as antagonistic to a compound causing dopamine release by the nature of it's inhibitory action). Hope that helps.[[User:87.102.33.144|87.102.33.144]] 13:04, 28 January 2007 (UTC)
::Actually, antagonism and inhibition are two distinct concepts in most biomedical contexts. Antagonism usually refers to interference with the ''action'' of a substance, or sometimes to the production of an effect that opposes that of another substance. An example of a steroid antagonist is [[spironolactone]], which reduces [[mineralocorticoid]] effects and [[androgen]] effects. Inhibition usually refers to interference with ''production'' of a substance. An example of an inhibitor of steroid production is [[metopirone]]. [[User:Alteripse|alteripse]] 17:22, 28 January 2007 (UTC)
:::I see that [[competitive anatagonist]], [[noncompetitive antagonist]] & [[uncompetitive antagonist]] need articles...I'll have to work on that.
:::For maybe a litle semantic clarity of the difference between antagonism and inhibition...Inhibition is the prevention of some event and antagonism is one biochemical pathway through which one might cause inhibition. Enzymes or biological receptors, for example, can be inhibited by several means (phosphorylation state, missing co-factors, pH, etc.), including antagonism. An antagonist may inhibit by one of several methods (see below), but chiefly it interrupts the the otherwise natural activity of the enzyme/receptor in the local state. [[Enzyme inhibitor|Types of enzyme inhibition]] | [[Competitive inhibition]] | [[Uncompetitive inhibition]] | [[Non-competitive inhibition]] | [[Suicide inhibition]] | [[Mixed inhibition]] | -- [[User:Scientizzle|Scientizzle]] 00:22, 30 January 2007 (UTC)
::::I am inclined to agree with [[User:Alteripse]] & [[User:Scientizzle]], otherwise I wouldn't have asked the question, because I already read the dictionary before asking the question. --[[User:Parker007|Parker007]] 05:52, 2 February 2007 (UTC)
:::::Wow, so biochemists can just make up new definitions of words can they! If 'you' used the words in correct context of their english meaning maybe you wouldn't have this problem???[[User:87.102.4.6|87.102.4.6]] 10:38, 2 February 2007 (UTC)
I'd just like to point out that we ''do'' have articles on [[Receptor antagonist]] and [[agonist]], as well as the featured atricle [[Enzyme inhibitor]], which also was linked to above. It might be better to expand on those, and add some redirects, rather than create new articles. --[[User:NorwegianBlue|NorwegianBlue]]<sup>[[User_talk:NorwegianBlue| <u>talk</u>]]</sup> 09:24, 2 February 2007 (UTC)
:Yeah...I know. I was considering how best to go about either combining receptor dynamics into the enzyme inhibition articles or making new, separate articles. Receptors and enzymes are very unrelated in terms of activity, and are separate targets for drug interactions (through which most antagonism occurs), but the molecular methods and pharmacological models of inhibition are largely similar...I'll figure it out... -- [[User:Scientizzle|Scientizzle]] 16:14, 2 February 2007 (UTC)
How do [[enzymes]] have anything to do with [[neurotransmitters]]? --[[User:Parker007|Parker007]] 09:41, 2 February 2007 (UTC)
:Enzymes are to substrates as receptors (eg, neurotransmitter receptors) are to ligands (eg, neurotransmitters). --[[User:Diberri|David Iberri]] ([[User talk:Diberri|talk]]) 01:19, 3 February 2007 (UTC)
::That makes no sense; So what does [[enzymes]] do to [[neurotransmitters]]? --[[User:Parker007|Parker007]] 00:10, 4 February 2007 (UTC)
:::What David Iberri is trying to say is that the interaction between [[enzyme]]-[[substrate]] is [[analagous]] to [[receptor]]-[[ligand]]. The [[kinetics]] are often very similar. -- [[User:Scientizzle|Scientizzle]] 07:31, 4 February 2007 (UTC)
::::In english? :) --[[User:Parker007|Parker007]] 06:11, 9 February 2007 (UTC)
:::An enzyme binding to its target substrate exhibits very similar kinetics as a receptor binding a signaling molecule. The final action is different (enzymes will alter the substrate in some way, a receptor will activate a distal signaling pathway, without altering the signaling molecule), but the modeling is similar. Is that any better? -- [[User:Scientizzle|Scientizzle]] 16:02, 9 February 2007 (UTC)
== Bending of light. ==
Why does a light ray bend when there is mass in vicinity of it's line of journey?
Considerable bending has been observed when the amount of mass is large.Does bending occur even when amount of mass is small?Is there any relation between gravity and electromagnetism?Well, something fishy is going on.I think unification of gravity and electromagnetism is not far.(Ecclesiasticalparanoid) <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/210.212.215.141|210.212.215.141]] ([[User talk:210.212.215.141|talk]]) 10:13, 2 February 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
*[[Light]] is an odd thing. It can behave both like a wave and like particles. Since particles have mass, they are affected by the gravitational pull of a mass in its vicinity. Light probably bends too when the mass is small, the effect is just smaller. 'Small' is a relative term in that case. Usually we're talking planet-sized masses in discussions like this. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 10:59, 2 February 2007 (UTC)
:At the moment there is no known way to unify gravity and electromagnetism into one force though it is presumably the goal of a Theory Of Everything. Many people have sought such a connection, including Albert Einstein (see [[Unified field theory]]), and failed. Whether it is far away or not probably depends on whether you think they are going the right direction with [[string theory]] or not. --[[User:24.147.86.187|24.147.86.187]] 13:33, 2 February 2007 (UTC)
::Unless I'm mistaken, classical electromagnetism and modern gravitational theory (general relativity) have already been shown to be consistant.My answer to your last question contained a link to [[Kaluza-Klein theory]], which shows that [[Maxwell's equations]] (the basis of classical electromagnetics) can be derived from principles in general relativity.In other words, KK theory more or less united modern gravitation theory and classical electromagnetics back in the 1920s.
::Also note that it isn't just light that exhibits [[wave-particle duality]], but all matter at sufficient scales.However, pertaining to the question you originally posed, I'm not sure if it's totally appropriate to embark on a discussion of quantum mechanical effects (which is where you would consider wave-particle duality).In general, QM and GR haven't been reconciled, so I don't know if it's appropriate to talk about wave-particle duality in the same breath as gravitational (spacetime) effects on light.Look at [[Maxwell's equations in curved spacetime]] and [[General relativity]].Perhaps a physicist can fill in some of the gaps I've omitted in my explanation...I'm definitely not a GR person, and I can only do fairly basic QM.
::P.S. - The [[photon]] is massless (at rest). -- [[User:Matt Britt|mattb]] <code>@ 2007-02-02T13:42Z</code>
:I believe the current understanding is that the light really doesn't bend. It travels straight in [[spacetime]] and it is spacetime itself that is distorted by the presence of the [[mass]]. The analogy usually used for us non-[[physicist]]s is to imagine spacetime as a [[rubber]] sheet and the massive objects as heavy objects pressing down into that rubber sheet. The depressions thereby formed are analagous to the bends in spacetime.
:[[User:Atlant|Atlant]] 14:07, 2 February 2007 (UTC)
:: Light also distorts space-time depending only on it's frequency. The fundamental understanding of Einstein's theories is that Energy and Mass are equivalent. --[[User:Tbeatty|Tbeatty]] 07:09, 3 February 2007 (UTC)
If i remember correctly Lightning consist of Plasma, which is a super hot gas; gas has mass. in anyway if your talking about lightning i can see why it would bend, however if you were talking about regular light, light accelrates Ions or electrons or something (someone here should know) in anyways these ions or electrons also have a mass (although its not much its still there) that would explain how a high gravity mass can alter light in such ways. [[User:Maverick423|Maverick423]] 15:07, 2 February 2007 (UTC)
:Nobody said anything about lightning as far as I can tell.Please don't take this the wrong way, but given your second sentence I would suggest reading some of the linked articles.The article on [[light]] itself provides a pretty good overview. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-02T15:13Z</code>
Meh sorry and thanks for the corrections its been a while since i read or studied about light so i can get my info confused at time =( [[User:Maverick423|Maverick423]] 15:32, 2 February 2007 (UTC)
:No need to apologize.I'm by no means an expert on modern physics, and I've probably said some things that aren't totally accurate.Just take a moment sometime to read that article on light. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-02T15:40Z</code>
== Statistics/Normal Distribution ==
(repost of a question previously posted on another reference desk and previously moved to the math desk. Te Q and A have been moved there as well. Please do not doublepost.)[[User:Edison|Edison]] 16:17, 2 February 2007 (UTC)
== Another poision question ==
Hi there again its me! im sure you know me from my old question from radiation =P anyways here i go again. my curiosity has gotten Intrested in the cyinade (think thats how its spelled). Cyinade Poisioning yes it says its fast and kills rapidly, but exactly how does it do it? What does a person feel (yes i am intrested in stuff like this as you can see) when they get cyinade poison? does the skin melt does the person feel immense pain or is it just a drink and fall dead with no feelings of the poison coursing through your body?? what about the range of cyinade? how far can it reach if a cup of it was spilled on the floor and how fast does it evaproate? there are lots of questions about this i want awnsered but well i dont know if people sugar coat it when they talk about it or what but please guys DONT sugar coat it i am intrested in the raw effects of it. thanks [[User:Maverick423|Maverick423]] 15:24, 2 February 2007 (UTC)
:Ok try not to get carried away - the skin does not melt.
:''Cyanide poisons (in one way I know of) by complexing to metal ions such as the iron in haemoglobin'' - (it may be poisonous in other ways) - this is similar to [[carbon monoxide]] poisoning - <s>effectively you aspyhyxiate due to lack off oxygen</s>.
:The 'cyanide capsule' is often [[sodium cyanide]] solution.
:[[Hydrogen cyanide]] is a gas and also poisonous.
:In the case of swallowing cyanide choking and spluttering occurs - followed by loss of conciousness - the death. There is not much pain - but the choking and spluttering is unpleasant but not that bad.. People poisoned by cyanide can be saved - the longer they are out the less chance they have of surviving.
:Sodium cyanide and [[potassium cyanide]] are solids - as solutions they may produce a small amount of hydrogen cyanide - adding an acid to a cyanide salt will produce the [[hydrogen cyanide]] gas - this is capable of spreading - I don't know how fast though.
:Interestingly [[hydrogen cyanide]] will burn.
:The cynanide links above all give more info on mode of action and lethal doses etc. Suggest you read them..[[User:87.102.4.6|87.102.4.6]] 15:49, 2 February 2007 (UTC)
Alright great info man thanks much! so then what they say about cyanide being a quick and painless death is a lie? i kinda figured there was something about that line. well anymore information is greatly appreciated as for me i got some stuff to look at thanks again! [[User:Maverick423|Maverick423]] 15:57, 2 February 2007 (UTC)
:I'm afraid much of the above is incorrect. Cyanide does not act on hemoglobin, but on cytochrome oxidase, as a ''metabolic poison''. [[Cytochrome oxidase]] is an important [[electron carrier]] in the [[electron transport chain]]. It is a necessary component of mitochondrial respiration, and without it the mitochondria are not able to induce a [[proton]] gradient for their [[ATPase]]. Cyanide binds to cytochrome oxidase and renders it useless. Also, death from cyanide poisoning would probably not be very painful; first, it only takes about a minute to become unconscious with a reasonable dose, and second, reduced [[ATP]] would not be likely to initiate [[nociception]] in the appropriate nerves until long after a victim was unconscious (if at all). Usually the "choking and spluttering" described above does not happen while the patient is conscious. A time course might look like this: cyanide is introduced to bloodstream, cyanide enters central nervous system and renders the (high ATP consuming) neurons unable to function, unconsciousness occurs, cyanide in heart renders Ca++ uptake/sarcomere resetting impossible via reduced ATP, cardiac arrest occurs, rest of cells in body die either from cyanide exposure/ATP paucity or anoxia resultant from cardiac arrest. <sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .1em .1em .9em .1em;">tucker</font>]]</sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .35em .1em .35em .1em;">/</font>]]<sub>[[User:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .9em .1em .1em .1em;">rekcut</font>]]</sub> 22:52, 2 February 2007 (UTC)
thanks much for the corrections and thanks much IP dude for telling me about the corrections on my talk page =). I will ask another question about the information on the bottom in a bit because by this time many people dont read this far up. [[User:Maverick423|Maverick423]] 22:44, 5 February 2007 (UTC)
== body temperature ==
How do you raise your body temperature? <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:Andiman56|Andiman56]] ([[User talk:Andiman56|talk]] • [[Special:Contributions/Andiman56|contribs]]) 15:26, 2 February 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
Ahh good one well there are many ways to do this. one such way is exercising. the other is involenttary shivering in the cold. [[User:Maverick423|Maverick423]] 15:33, 2 February 2007 (UTC)
: Give it better [[food|fuel]]. [[User:Vranak|Vranak]]
:Put more layers of clothing on. Eating spicy food feels like it does too, but I don't know if it does. A hot drink and hot food. Lower your exposed surface area by huddling as tightly as you can. [[User:Skittle|Skittle]] 17:25, 2 February 2007 (UTC)
:Spicy foods actually help lower body temperature. Thats one of the reasons why they are consumed in warmer climates. --[[User:Russoc4|Russoc4]] 04:18, 3 February 2007 (UTC)
::Indeed. You eat spicy foods, which causes you to [[sweat]], which leads to puuuuuuure coolness! − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 09:00, 3 February 2007 (UTC)
Increase the speed of your metabolism, so you produce heat faster from your food:)[[User:Hidden secret 7|Hidden secret 7]] 20:56, 3 February 2007 (UTC)
== Feeling Gassy ==
Are there foods that I can eat during the day (at work) that causes the LEAST gas?I seems that no matter what I eat, I end up feeling uncomforatable all day or until I relieve myself...
:As you know, we can't give medical advice. But I think it's safe to mention that any [[Carbonation|carbonated]] beverages (such as [[Soft drink|soda]]) will free their [[carbon dioxide]] gas inside of you and it's got to go somewhere.
:[[User:Atlant|Atlant]] 16:19, 2 February 2007 (UTC)
:This shouldn't be a request for medical advise.If you would like for me to rephrase it, what type of foods would cause the least amount of gas produced in the stomach for humans?I am assuming that vegatables like broccoli is one of the culprits, but what other types of foods?
::[[Peppermint tea#Health benefits and concerns|Peppermint tea]] can help settle the gastrointestinal system.[[User:Vranak|Vranak]]
:[[Flatulence#Causes]] may be of some help -- [[User:wikicheng|Wiki'''''Cheng''''']] | [[User talk:wikicheng|Talk]] 10:56, 3 February 2007 (UTC)
I heard [[ginger]] is good for seyyling the gutts
== Muscle Cramps ==
I infrequently get cramps in various muscles.Most often in my calves.However, I have found that I can make myself get these cramps very easily by holding my calves or bicepts in a flexed position.My question is what do these cramps do to the muscles in which they occur?Is it like lifting weights at all, or is it somehow detrimental?Thank You. <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:66.99.100.66|66.99.100.66]] ([[User talk:66.99.100.66|talk]] • [[Special:Contributions/66.99.100.66|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
: How does your leg feel afterwards – better or worse? [[User:Vranak|Vranak]]
:I don't have an answer to your question, but FYI a common cause of calf spasms is [[Hypocalcaemia#Effects|calcium deficiency]]. [[User:Anchoress|Anchoress]] 17:16, 2 February 2007 (UTC)
== CD28 gif 3d rotating structure ==
I really enjoyed the rotating 3d image of CD28 on your CD28 page.My question is simply that I would like to know if I could use your .gif format software (code) to portray the 3d structure of another protein molecule for which I have the .pdb file (3d coordinates)on my website?Can you please help me with how to do this if it is indeed legal?Thanks again for another terrific Wikipedia page, as always!
Don Kaiser
<Rm email to reduce spam>
*If you click on the image, you will find yourself on a page that indicates who created it...ask him how he did it. I've used the free [[Jmol]] program to make 3D molecular models from PDB files. I think it can export animated gif images, but not sure. [[User:DMacks|DMacks]] 20:48, 2 February 2007 (UTC)
==Plantiferitus==
Plantiferitus... what is this word? It is a very painful foot condition and I can't remember it. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 18:18, 2 February 2007 (UTC)
Have you tried at "foot.com" http://www.foot.com/info/info_cond.html
[[Plantar fasciitis]]. ?[[User:83.100.183.48|83.100.183.48]] 18:30, 2 February 2007 (UTC)
== abnormal oozing of blood from skin,teeth etc ==
recently came accross a person suffering from peculiar problem of loosing blood from skin,has already supplemented 3 bottles of blood in last 2 year.Seems condition is detoriaoting day by day.Blood report are about to come in few days.Pls advice. <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:59.93.247.53|59.93.247.53]] ([[User talk:59.93.247.53|talk]] • [[Special:Contributions/59.93.247.53|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
:Have them see a doctor. Considering that a blood report is being performed, it seems this if being taken care of. We can not provide medical advice. -- [[User:Consumed Crustacean|Consumed Crustacean]] <small>([[User talk:Consumed Crustacean|talk]])</small> 18:55, 2 February 2007 (UTC)
Think this person your talking about might have [[Hemophilia]]. im not sure but u might wanna check it out and compare. [[User:Maverick423|Maverick423]] 20:30, 2 February 2007 (UTC)
::Are you the patient, a friend of the patient, the nurse, or what? Your IP suggests Australia. Don't they have an established health system there which could diagnose and treat the problem? [[User:Edison|Edison]] 03:40, 3 February 2007 (UTC)
==hovercrafts==
Is it possible that in the next 20-30 years, we would have hovercrafts as a normal mode of transportation replacing automobiles?
:I think it's unlikely since hovercrafts expend (quite a lot of) energy just to keep themselves of the ground - so I'd suggest that they are intrinsically less efficient. Plus they are not as easy to steer as cars especially in a high wind - they definately wouldn't be good on motorways - unless they had big bumpers like [[dodgems]]. Given that it seems important to increase fuel efficiency I think the answer is definately most unlikely.[[User:83.100.183.48|83.100.183.48]] 20:18, 2 February 2007 (UTC)
i dont know about hover cars however i do know that this car has been in prototype testing for quite some time and is already being considered for mass production soon! check out the [[Moller Skycar]] [[User:Maverick423|Maverick423]] 20:36, 2 February 2007 (UTC)
:That's what they told us 10 years ago about that Skycar... Face it, it's not going to happen. — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 21:42, 2 February 2007 (UTC)
Aw kieff come on its possable sooner now then later. after all they are getting the permission from that agency that says its ok to fly them. since the car is also in production and has actually flown, the chances of it comming out soon is great. Moller said his car was going to come out by 2008 and then mass produced by 2012. people have already bought the car itself and are going to recive it soon. also in Iran they are also making a flying car that is going to be used in rescue and police related instances. http://www.cnn.com/2007/TECH/01/31/israel.flying.car.ap/index.html
http://www.moller.com/purc.htm
[[User:Maverick423|Maverick423]] 21:55, 2 February 2007 (UTC)
Flying cars - are you mad - I can just imagine coming home oneday and finding one sticking out of my roof.. Hopefully never[[User:83.100.183.48|83.100.183.48]] 22:14, 2 February 2007 (UTC)
dont ya worry the flying car has full safety features including backup engines, full car parchute, GPS locater, Automatic GPS Driver. simply enter the place you want to go and sit back and read a book the car will do the rest itself! Read Mollers Website to find out more on the car itself. Crashes will be reduced massively! [[User:Maverick423|Maverick423]] 22:50, 2 February 2007 (UTC)
:The thing has barely hovered so far, and this project has been going on as far as I can remember. I can't see something like that becoming mainstream and affordable in the near future. — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 01:34, 3 February 2007 (UTC)
Ah but the smaller version of the car has already flown across the country in previous test. its smaller (1 passenger) and ligheter and has more power (10 Engines 5 main 5 back up) instead of the 8 (4 main 4 back up). it goes faster and uses less fule since it is lighter. i think the problem with the 4 passenger one is that it only has 8 engines and uses more fule its less how can i say it? well i guess cost effectiveness is less for that one. think the smaller version has already been proven to go 64 miles per gallon then the bigger version (which only hovers) at 20 miles per gallon. tell ya what ill get back to you with this one i just need to make sure k. [[User:Maverick423|Maverick423]] 20:05, 3 February 2007 (UTC)
ahh sorry here it is it appears that the smaller version has this http://www.moller.com/m150.htm
( i took out the list that i placed cause it was bigger then i thought so i just linked it for ya ((should of done that to begin with)))
well those are the specifications on that 1 passenger one so the engines are acctually 2X2 engines[[User:Maverick423|Maverick423]] 20:22, 3 February 2007 (UTC)
I really don't expect a project like this will ever get off the ground:@[[User:Hidden secret 7|Hidden secret 7]] 21:00, 3 February 2007 (UTC)
Acctually from what i heard the plane and the car were both being considered for use in public travel. the only problem was that planes were more expensive to buy then cars used more fule and needed a flat surface to take off. that is what made the car as the primary mode of transportaion. if these issues were assest from the begining we would be saying traveling on the ground is impossable or primitive. [[User:Maverick423|Maverick423]] 15:26, 5 February 2007 (UTC)
== Do Snails Have Eyelids? ==
I was wondering if snails have eyelids.
Thanks!
It seems not - but the eyes are on muscular stalks and can be retracted - in fact snails don't have very good eyes apparently - relying more on touch and taste - the entire body is a bit like one big tongue.
:See this website http://www.applesnail.net/content/anatomy/senses.php for more info on one type of snails eyes - a bit of the way down there's an diagram/image showing just how bad their eyesight is - it's probably not worth them having eyelids anyway.[[User:83.100.183.48|83.100.183.48]] 20:38, 2 February 2007 (UTC)
== Deep Fat Frying ==
Does deep fat frying potato chips (including the skins) reduce the nutritional value? I don't care about the fat that's added (I only eat them on occasion) but rather the nutrients that may be leached out or otherwise rendered useless. --[[User:Seans Potato Business|Seans]] '''[[User talk:Seans Potato Business|Potato Business]]''' 20:45, 2 February 2007 (UTC)
:Some vitamins, [[Vitamin C]] for example (and including other water-soluble vitamins if I'm not mistaken), are sensitive to high cooking temperatures. Although [[Vitamin_C#Food_preparation|this section]] seems to contradict what I said (but note the fact tag), so maybe my belief is in error. [[User:Anchoress|Anchoress]] 21:09, 2 February 2007 (UTC)
::Flash frying (don't know if we have an article) preserves many sensitive compounds due to the short time the stuff in the the pan - plus I don't think water solubilty has a lot to do with it - that would be boiling - it's all a matter of degree - it's usually air (oxygen) that degrades vit C - so a minute at 200C probably won't make much difference - though obviously prolonger frying will degrade all the nutrients.[[User:83.100.183.48|83.100.183.48]] 21:23, 2 February 2007 (UTC)
As a rule I'd say no - with modern preparation methods the degredation is very small - the time on the shelves way have a bigger role - though if the food package is airtight/block out light this shouldn't be a problem either - In general the nutritional value is increased by frying - by virtue of the increase in calorific value due to the fat; this doesn't apply if you are supposed to be on a diet obviously..[[User:83.100.183.48|83.100.183.48]] 21:27, 2 February 2007 (UTC)
== Need help at [[Big Bang]] ==
There are some edits there today that I don't agree. Can we have some physicists over at [[Big Bang]]? Thanks. [[User:Xiner|Xiner]] ([[User talk:Xiner|talk]], [[Special:Emailuser/Xiner|email]]) 20:52, 2 February 2007 (UTC)
:Christ - good luck - as the big bang is speculative (or not if you're a big bang scientist) - this entire topic is open to original research and speculation. For instance this difference http://en.wikipedia.org/w/index.php?title=Big_Bang&diff=105174931&oldid=105171230 replaces expands on something that is already purely speculative - what is one to do?[[User:83.100.183.48|83.100.183.48]] 21:02, 2 February 2007 (UTC)
:However if the edits get too much for you, you can always fall back on our good old friend {{fact}} - use <code><nowiki>{{fact}}</nowiki></code> - I'd suggest removing debateable parts to the talk page - stating your reasons for the removal and suggesting that adequate citations are provided before it's readdition.[[User:83.100.183.48|83.100.183.48]] 21:06, 2 February 2007 (UTC)
:Plus there are so many variants on this theory in terms of explanation and outcome that you've got a real minefield..[[User:83.100.183.48|83.100.183.48]] 21:10, 2 February 2007 (UTC)
:Could you say which edits were problematic?[[User:83.100.183.48|83.100.183.48]] 21:10, 2 February 2007 (UTC)
::Actually, the one you pointed out is the one I'm having most trouble living with. I don't mind speculations, but this guy is putting things down as fact, with no way to check its veracity. He's editing a lot of articles too. [[User:Xiner|Xiner]] ([[User talk:Xiner|talk]], [[Special:Emailuser/Xiner|email]]) 21:20, 2 February 2007 (UTC)
:::I'd suggest the method of removing and asking for citations - that's the way here I've learnt - even if the guy's right... Mention that the information must be verifyable - see [[Wikipedia:Verifiability]] "The threshold for inclusion in Wikipedia is verifiability, not truth" that's official policy.
:::It looks like they are adding fairly respectable explanations-I wouldn't expect it to be difficult to find citations for them - but I doubt that those explanations are the only subsets of the theories out there..I'm sure there are many other ones - The article might need a rewrite to cover the various possibilities and explanations thereof - with a non-contentious introduction.
:::I'd say the second paragraph about the 'origin from nothing' either has or should have it's own article - the info is relevant - but I'm not sure how much in the context of the article being called 'big bang' - it would be worth pointing out that the two theories are consistent in this respect - but I don't think in the main body of the article - maybe in a 'comparison with other cosmological theories' section. If the two were inconsistent that would be worth noting too.[[User:83.100.183.48|83.100.183.48]] 21:48, 2 February 2007 (UTC)
::::I see. I'll see what I can do. Thanks a lot for the advice. [[User:Xiner|Xiner]] ([[User talk:Xiner|talk]], [[Special:Emailuser/Xiner|email]]) 22:04, 2 February 2007 (UTC)
By the way I do it like this (on the talk page):
<blockquote>
..Removal of .... ..
I removed this text "the x is y because of z" because I'm unsure/think it's wrong/think it's exaggerated/think it's in the wrong place...
Could somebody please provide a reference for this infomation before re-adding it.
or
This is not relevant to the section it's in and should be in a new/existing section - I will/could you create such a section..
or
Shouldn't this be in a separate article - named '....' -
</blockquote>
I wouldn't recommend just removing stuff without pasting it to the talk page - that can be annoying/seem aggressive.. (unless of course it is obviously vandalism - not the case here).
If you copy debated stuff to the talk page then they can discuss it there or they haven't got a leg to stand on - separates the reasonable from the unreasonable people. Also (from experience) if someone makes grammatical changes - don't revert - make little edits (taking into account their addition) until the article is satisfactory to all of you - that works too (though it can be very time consuming) -
I don't envy you...probably one of the worst articles to have on your watchlist, [[jesus]], and [[george bush]] being slightly worse.[[User:83.100.183.48|83.100.183.48]] 22:10, 2 February 2007 (UTC)
== Stick bomb. ==
I was reading the article [[stick bomb]] and a quick google search on it didn't really tell on how to construct one. Is there a website that shows how, that perhaps I missed? --[[User:Proficient|Proficient]] 21:34, 2 February 2007 (UTC)
:I agree that there should be the basic popsicle stick bomb I made as a kid. Somebody will have to whip up the 3D software and make a model! (Perhaps me, one day). --[[User:Zeizmic|Zeizmic]] 22:10, 2 February 2007 (UTC)
::Is that article a copy-vio, or is it just really weirdly written? I can't see any of it on Google, but Google isn't the world. I've never heard of stick bombs before, so I can't really do more than remove references to an 'Author'. Anyone here able to improve it? [[User:Skittle|Skittle]] 22:43, 2 February 2007 (UTC)
::Me neither, and I'm guessing that's not their running name then. The current article is an obvious self-promotion by that Tim guy, so if you guys think this stuff is notable enough for an article, rename, rewrite and get us some sources. — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 01:30, 3 February 2007 (UTC)
:This video has instructions for the type I used to make as a kid: http://www.youtube.com/watch?v=KyzsDmkYnJY [[User:75.138.84.159|75.138.84.159]] 00:58, 3 February 2007 (UTC)
== Point drag coefficient ==
Does anyone know the definition of the point drag coefficient? What I know is as follows...
<math>C_{D} = \int^{+\infty}_{-\infty}{{C_{D}}'\,d(\frac{z}{c})}</math>
where <math>C_{D}</math> is the drag coefficient of the aerofoil, and c is the chord length. <math>{C_{D}}'</math> is apparently the point drag coefficient. Can anyone tell me the definition of <math>{C_{D}}'</math>? I have the <math>{C_{p}}</math> distribution over the aerofoil, which I presume is needed. Thanks! [[User:Readro|Readro]] 22:56, 2 February 2007 (UTC)
:The point drag coefficient <math>{C_{D}}'</math> (or section drag <math>C_{d}</math>, as I learned it) is the coefficient of drag for a 2-D cross section, with chord length replacing wetted area to nondimensionalize the drag per section span. It seems what you have is the definition, that is if you split the wing into infinitely small cross sections, each cross section will have a section drag coefficient. Integrating all of these over the wing span gives the total drag coefficient <math>C_{D}</math>. [[user:anonymous6494|anonymous6494]] 00:30, 3 February 2007 (UTC)
= February 3 =
== Abs and Resting Time ==
How often can you work out your abs without them needing rest? I've heard that you can work out the abs nearly every day, whereas the other muscles need rest. Why the difference? Also, how much resting time is needed for abs? [[User:PitchBlack|<font color="purple">PitchBlack</font>]] 03:45, 3 February 2007 (UTC)
:Do sit ups until it hurts? --[[User:Russoc4|Russoc4]] 04:17, 3 February 2007 (UTC)
::I didn't find any real sources, but google results did say to treat your abs like any other muscle and excercize them about 3 times a week. On a related note, [http://www.6weekabs.com/7mythsaboutabs.htm 6 Week Abs] has 7 myths about abs. I'm curious now too, because when I used to work out (yea, yea, I got lazy), I could lift barely more than I weigh with my upper body, but I can use ab machines at max weight and not have them hurt afterwards while my arms did. --[[User:Wirbelwind|Wirbelwind<small>ヴィルヴェルヴィント</small>]] ([[User_talk:Wirbelwind|talk]]) 06:19, 3 February 2007 (UTC)
:I have never had sore abs when I would exercise them 5-6 times a week, whereas my arms and legs needed a day to rest afterwards. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 23:50, 3 February 2007 (UTC)
== A plant that is also a pathogen ==
I recently added to the article [[protothecosis]] that ''Prototheca'' was the only known [[pathogen]] that is also a plant. I got this from the ''Journal of Clinical Microbiology''. Is it true, or am I forgetting some other plant that causes an infectious disease? --[[User:Joelmills|Joelmills]] 04:19, 3 February 2007 (UTC)
:Wow, that's pretty cool. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 05:26, 3 February 2007 (UTC)
::Hello Joelmills, this is very nice, but when you're not sure, why not asking before updating ? Now it's only because fungus are not sorted along with plants that your first case [meaning of prototheca] is an 'only plant' [[candidiasis|candidate]]. --[[User:Harvestman|<font color="blue"> DLL </font>]] <sup>[[User talk:Harvestman |<font color="green"> .. T</font>]]</sup> 10:57, 3 February 2007 (UTC)
I was sure when I added it, having the reference to back me up and a precursory google search not showing any contradiction. But then I thought that it was a pretty big claim to make, so I better ask here, where I know that there are a lot of knowledgable people. Protothecosis hasn't attracted many edits in the months it's been in existence, so I figured a few hours of waiting to doublecheck something was OK. --[[User:Joelmills|Joelmills]] 19:37, 3 February 2007 (UTC)
== Wireless control ==
HI friends,I have undertaken a project "Multi-axis wireless control for Robots".In it's details,all I have to do is to control the robot using my transmitter pad.I have planed to use 5 to 6 keypads to control different axis.Then at the receiving end,using some RF module,the data is decoded and it will be used to control the relay using a microcontroller and ULN driver.Which will then be interfaced to PLC for robotic arm movement....For this entry level,I have stuck somewhere in choosing the exact means of communication.At first someone stated to go for IR,later someone suggested RF and now few others state to pick bluetooth for industrial standard...Now I have decided to ask to you guys in this forum so that I can get a good solution for this..For IR based TX and RX,I have seen many circuits practically used,but I still can't get one for multiple device control...For Rf based TX and RX,I tried MAXIM-1472(TX) and 1473(RX)...All pin connections and other spec seems pretty nice but I'm not able to get any practical circuits for it's contruction.I also tried Cypress wireless solution.But the practical construction seems almost impossible...Should I have to only buy modules?.Isn't there any other solution?..Guys can anyone get me some more detailed view in designing using such SOCs please?..I don't know what type of data format that should be used for this chip.No proper details in Maxim Website...I tried...Please someone help me out...And about bluetooth project,I have simply no idea...I thank you all in advance for you consideration..Looking up for the suggestions........ <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:59.96.23.95|59.96.23.95]] ([[User talk:59.96.23.95|talk]] • [[Special:Contributions/59.96.23.95|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
:I'm slightly confused about what you're asking. When you mean practical circuit, you mean you can't do it because the traces of the MAX1472 and 1473 are too small, or you don't have a schematic? IIRC, one of those is [[TSSOP]] and have a pin clearance of like 0.2 mm or something tiny. There are adaptors available for them, I believe, which cost around $10 a piece. But even then, they're [[Surface-mount technology|surface mount]]. I'm not sure what your level is, etc, so it's hard to tell if I can even provide you an answer when you ask for a more detailed view in designing. The datasheet usually has that kind of info, and the 1472/1473 uses [[Serial Peripheral Interface Bus|SPI]] I believe. If the problem is that you're making prototypes, you should look for [[Dual in-line package|DIP]] packages for chips to construct them easily. Somehow, I doubt I helped any, so do tell if anything applies, and if not, what info you need (design software, RF packages, comparison of RF / Bluetooth / IR, etc). --[[User:Wirbelwind|Wirbelwind<small>ヴィルヴェルヴィント</small>]] ([[User_talk:Wirbelwind|talk]]) 08:54, 3 February 2007 (UTC)
== How does window gel work? ==
My kids have window gel toy stickers (hearts, snow flakes, and so on) that stick to non-porous surfaces like windows, mirrors, and metal. They don't stick to fingers. From my research all I've been able to determine is that window gel toys are primarily manufactured in China and South America, mostly Brazil.
What is window gel made of? How is it made? How does it work? Does it leave a film behind? <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:Dstinchf|Dstinchf]] ([[User talk:Dstinchf|talk]] • [[Special:Contributions/Dstinchf|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
:They appear to be static cling [[vinyl]]. See also [[Colorforms]]. --[[User:Wirbelwind|Wirbelwind<small>ヴィルヴェルヴィント</small>]] ([[User_talk:Wirbelwind|talk]]) 17:50, 3 February 2007 (UTC)
== Unknown Bird ==
Found browsing flickr : "IF anyone know the bird's name please write clicking the comments link. "
http://www.flickr.com/photos/subirbose/167852801/. Seems the guy's photos are from the [[Himalaya]] and surroundings. Thanks for your help and more : which method do you use and recommand to find the name of a [living creature] from its photo or sketch ? --[[User:Harvestman|<font color="blue"> DLL </font>]] <sup>[[User talk:Harvestman |<font color="green"> .. T</font>]]</sup> 10:50, 3 February 2007 (UTC)
:To find a species, you want to use an [[Identification key]]. There are plenty around; you'd need to find one for the class [[Aves]] (birds) to find the identity of this bird. [[User:Smurrayinchester|<span style="color:#BBBB00">Laïka</span>]] 13:18, 3 February 2007 (UTC)
== Skin aging ==
I was trying to find some information on the process of the aging of the skin, and I guess both physical aging in general and the (human) skin are not as well covered, unfortunately, as some other biology-related topics on WP. I am particularly interested in how the dermis ages vs. the epidermis - it is my intuitive understanding that while the epidermis' aging concerns wrinkles and other skin imperfections more, it is the dermis' aging that is responsible for the sagging of the skin and the fact that our cheeks and neck don't look south youthful anymore :(
I was inspired to research Wiki for that by reading about this company's product: [http://www.genuinecollagen.com/TheScienceBehind.shtml#]. Even if their product actually works, it is my understanding that it affects epidermis only (even if it's "all five layers of the skin" as the company claims, I understand it is epidermis), so the product wouldn't prevent the skin from sagging anyway. OTOH, Wikipedia says stretch marks form in the dermis, and the company advertises using a "testimonial" from a customer saying her stretch marks have "faded" after using the product.
OK, what I would like to learn is how the skin actually ages and how, theoretically and practically, it can be prevented/alleviated, and what is the state of research into it - not to mention it would be nice to be able to find out the same about other tissues... I guess it is not a "question" one could answer overnight at the reference desk, I am rather counting on drawing the attention of editors who are into biology/medicine to that topic. It wouldn't hurt, though, if somebody could provide a quickie lowdown on the topic here :D
Thanks a lot to any merciful soul who would take interest in that request. [[User:PrinceGloria|PrinceGloria]] 11:17, 3 February 2007 (UTC)
== Energy saving Light bulbs? ==
I'd like to know just how much energy it takes to make an energy saving light bulb compared to the older glass filament type. It is widley known that the energy saving kind will use less energy to generate light of a similar intensity as a filament type and will last around ten times longer. But what about the enery of production? [[User:Hesaurus|Hesaurus]] 12:37, 3 February 2007 (UTC)
:See [[Talk:Compact fluorescent lamp#Energy used to manufacture CFLs]] [[User:Rmhermen|Rmhermen]] 01:38, 4 February 2007 (UTC)
==Genetic Variation in and between Populations==
I have heard many times, normally when discussing race and whether it exists, sentences like (and this is a real example from the reference desk) "there is more genetic variation among Africans than there is between Europeans and Africans".
What does this mean? That a randomly selected African will have more in common with a randomly selected European than another African? Because that sounds hard to believe. Or that the standard deviation in the African population is larger than the differences between an average European and African? [[User:85.1.5.207|85.1.5.207]] 13:37, 3 February 2007 (UTC)
:It means that there is more genetic variation within an African population than within a European population, measured by things like the number of minor varieties of genes (called [[polymorphism]]s). The most economical explanation is that several African "peoples" (i.e., populations, like Bantu, Khoisan, etc) partly separated from each other far longer ago than did the various European "peoples" (like Nordic, Mediterranean, Basque, etc). It does ''not'' mean that a random African is likely to share more gene polymorphisms with a random European than with another African. [[User:Alteripse|alteripse]] 14:22, 3 February 2007 (UTC)
::Thanks, although the statement made seems to suggest that there is more variation within Africans, than between Africans and Europeans. Are people who make this statement misunderstanding the claim, or is this a different claim? It is normally made in the context of proving how similar humans are, so we shouldn't be racist. Maybe it should be that we shouldn't lump all blacks together as one, which we don't do to white Europeans.[[User:85.1.5.207|85.1.5.207]] 14:45, 3 February 2007 (UTC)
:::Which "statement made"? A number of research studies have shown more genetic variation among the large population of people whose ancestors lived in Africa a couple of centuries ago than among those whose ancestors lived in Europe a couple of centuries ago. I do not know how to say it any more plainly. This statement itself is neither racist nor anti-racist. All of us recognize gradations of physical difference more easily among those who are most similar to the people among whom we grew up. This is the origin of the "all ___ look alike to me" kind of statement-- it reflects a nugget of truth about human perceptions and recognitions of other people, but it is an entirely relative fact, as the same assertion can be made by a member of the "other" population. Or should I have simply stopped at the first sentence? [[User:Alteripse|alteripse]] 23:34, 3 February 2007 (UTC)
:It means that two randomly selected Africans have less in common with each other than ''the average African'' has with ''the average European''. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 23:43, 3 February 2007 (UTC)
::The above statement is true, however: there is more genetic variation among Africans than among any other group (Asians, Native Americans, Europeans, Australian Aborigines). This is, in very simle terms, because they have been there the longest. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 23:45, 3 February 2007 (UTC)
:::Thanks to both of you. Alterprise, the statement I was referring to was the quote in my original post, but thanks for your info. The stuff I mentioned on racism was simply to try and clarify the difference between your explanantion and how I interpreted the original quote. Obviously facts cannot be racist or not, they are simply facts. Also thanks Twas Now for your answer, that would have been my guess but the statement seemed open to interpretation. (Same user - different IP!)[[User:137.138.46.155|137.138.46.155]] 08:05, 5 February 2007 (UTC)
== Sex in evolution ==
How can evolution explain how species evolved sexes? The primitive life forms didn't have sexes, so when did it all start? Did it have to evolve in one generation of a species? Or what? My biology teacher said that no-one really has an answer for this. Also, if natural selection or whatever found it necessary for two sexes to exist, will we be able to evolve a third or fourth sex? Please take this seriously, I'm not trying to attack evolution or anything, I'm just really interested in this. <b><FONT FACE="MS Reference Sans Serif" COLOR="#FF0000">► [[User:Adriaan90|Adriaan90]] ( [[User Talk:Adriaan90|Talk]] ♥ [[Special:Contributions/Adriaan90|Contribs]] ) ♪♫</FONT></b> 14:33, 3 February 2007 (UTC)
:Well, no one has a definite answer to this, though there is a lot of speculation going back even before Darwin's work. You might check out our article on [[evolution of sex]] for quite a lot of discussion of it. Once you've evolved sexual reproduction of this sort, the specialization of the different sexes to different functions, appearances, etc. is, I think, a comparatively easy thing to understand. --[[User:24.147.86.187|24.147.86.187]] 14:45, 3 February 2007 (UTC)
:[[Sex#Animal species]] shows that there are several animals with more than two sexes. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 23:41, 3 February 2007 (UTC)
::[[Yeast#Reproduction|Yeast]] is a "primitive life form," and it has a sexual form of reproduction, too. In fact, [[bacterial conjugation]] is kind of like sex. -- [[User:Scientizzle|Scientizzle]] 01:26, 4 February 2007 (UTC)
== Land fill solution or not...? ==
After watching the movie [[Soylent green]] and reading the article on [[Digestion]] I was wondering if it would be possible (and practical) to process solid waste both mechanically and chemically in a similar fashion as digestion or using the steps in [[Quantitative analysis]] or [[Qualitative analysis]] to produce a resource for useful byproducts such as plastics or for other purposes such as eliminations of [[Toxin]]s or [[Pathogen]]s? [[User:71.100.10.48|71.100.10.48]] 15:23, 3 February 2007 (UTC)
:Yes, indeed - I assume you mean household waste..
:There are methods similar to digestion for treating household waste, see [[Waste_management#Waste_management_techniques]] subsection '''Composting and anaerobic digestion''', also for sorting the waste see subsection '''Mechanical biological treatment''' - just as food is broken down in the gut by enzymes (an sometimes bacteria) - in the treatment of biodegestible household waste bacteria and enzymes break down some waste producing 'soup' that may be suitable for fertilizer, and possibly gas (methane). Any organic matter might be suitable for this - includes waste food obviously, but also wood, paper, some plastics, non synthetic clothes - it all depends on how good the bacteria are..
:As for a similar process to the steps in Quantitative analysis or Qualitative analysis - I assume you mean as in chemical analysis, and again the answer is a resounding yes.
:See subsection '''Pyrolysis & gasification''' in [[Waste_management#Waste_management_techniques]] - in this case waste is heated to a very high temp (eg much greater than 200 degrees C - maybe much greater than 1000C depending on method), but air (oxygen) is excluded so it doesn't burn - this causes all organic matter including synthetic plastics to break down (see also [[cracking (chemistry)]]) - the process typically yields a great mixture of products - that can be separated by distillation. It's comparable to the process where chemicals used to be obtained by heating coal (eg [[Karrick process]] or similar).
We have excellent articles on this see [[pyrolisis]] and [[gasification]] - both are great routes to synthetic 'diesel' and other petroleum replacement products - it's a form of recylcing of organic matter.[[User:87.102.9.55|87.102.9.55]] 16:20, 3 February 2007 (UTC)
If you want to read more I can suggest
[[Gasification#Gasification_process_examples]] and all the article [[pyrolysis]] - similar to chemical analytic methods.
For methods similar to digestion see [[Anaerobic digestion]]
If you look at the page on [[waste_management]] you may find other useful links.[[User:87.102.9.55|87.102.9.55]] 16:26, 3 February 2007 (UTC)
As for getting rid of toxins and pathogens - there is some infomation in the articles - the answer seems to be yes in some cases - specifically biological toxins.[[User:87.102.9.55|87.102.9.55]] 16:31, 3 February 2007 (UTC)
== This is not a joke and is not me trying to be sarcastic ==
This is not a joke so please answer seriously. Is it possible to kill someone by throwing (using their arms) an almond or a soybean at high enough velocity or by hitting a vulnerable part of the head. If you have heard any anecdotes of this please respond. Thanks. Again, this is not a joke, as ridiculous as it may sound. [[User:63.135.8.94|63.135.8.94]] 15:42, 3 February 2007 (UTC)
:No. A human arm can't give those objects enough kinetic energy to do any lethal damage on their own. But, I guess the person could choke and die of asphyxiation if it happened to go down their throats... — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 15:46, 3 February 2007 (UTC)
Even if the KE of the almond cannot exceed whatever amount of joules, is it not entirely impossible that it may hit a certain area of the head, such as a vein or artery or a nerve and cause death or serious injury? Thanks again for your previous reply[[User:63.135.8.94|63.135.8.94]] 15:54, 3 February 2007 (UTC)
:Sure it is ''possible'', but then any small, light object could also be considered lethal in these conditions. — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 16:15, 3 February 2007 (UTC)
:Even with the assistance of a [[sling]] or [[slingshot]], you need a projectile of at least 50 grammes to do any damage - many times heavier than an almond or soybean. The part of the body most vulnerable to injury by a small hand-thrown projectile is probably the eye. But I really don't see how it could be lethal (apart from the choking danger that Kieff mentioned). [[User:Gandalf61|Gandalf61]] 16:29, 3 February 2007 (UTC)
There are no parts of the head and neck that vulnerable to a small hand-thrown projectile in a healthy person If you want to make the person unusual, or if you want to add some more conditions, you can concoct all kinds of semi-plausible scenarios. The person has heart disease, gets angry, and dies of a heart attack. The person is standing on the edge of a crowded train platform as the train is approaching, and the thrown object startles him and causes him to fall in front of the train. The person is so depressed that this one additional unexpected expression of contempt and anger from a previous friend causes him to decide life is too painful. And so forth... [[User:Alteripse|alteripse]] 16:35, 3 February 2007 (UTC)
::It would be very, very difficult to kill (or even injure) someone with an almond or soybean. (Apart from Alteripse's "cooked" solutions, that is.) Theoretically, you can give even a lightweight projectile a lethal amount of momentum by shooting it fast enough. In practice, however, there are two crippling difficulties: (1) neither an almond nor a soybean is particularly aerodynamic -- they'd lose velocity rapidly between your gun and the target; and (2) neither an almond nor a soybean is particularly rigid, so it would be nearly impossible to accelerate them up to the stupefyingly high necessary velocity without disintegrating them. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 18:35, 3 February 2007 (UTC)
:If you think we don't take silly things seriously, check out [[Wikipedia:Reference desk/Archives/Science/2007 January 26 & 27#My other planet is made of meat]]. In high school, a guy I knew had a pencil thrown at him that lodged into his temple, and just stuck there. He was OK, and I think he didn't even notice until someone pointed it out. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 23:39, 3 February 2007 (UTC)
::I saw someone's eyeglasses broken by a thrown pingpong ball. An almond should have an easier time breaking the glass lens, and the broken glass could penetrate the eyeball leading to lethal infections. (Sure it's funny, until someone looses an eye) [[User:Edison|Edison]] 00:02, 4 February 2007 (UTC)
== Total Cholesteral Reduction ==
I am a 61 year old male. My TC was measured twice at a six month interval. It was 234 each time. The doctor reccommended exercise and diet to reduce the TC. I've engaged in 20 minutes per day of aerobic exercize and reduced my intake of cholesterol to less than 100 mg/day. I've also increased my intake of soluable fiber to more than 4 gm/day. I've followed a diet aimed at weight reduction and have lost 14 lbs in the last 33 days putting me at 192 lbs. What level of reduction in TC can I reasonably expect to achieve following this regimen? From a minimum to maximum?[[User:Brucearugg|Brucearugg]] 17:56, 3 February 2007 (UTC)
:Because your [[cholesterol]] levels are going to be based on the interplay of a number of factors – environmental ones related to the changes you've made in your behaviour as well as luck-of-the-draw genetics – and because you've made so many (healthy!) changes to your lifestyle, any answer we give you here would be no better than a wild guess.
:Moreover, total blood cholesterol is only one indicator of health. More important are the levels (absolute and relative) of [[High density lipoprotein|HDL]] (so-called "good cholesterol") versus [[Low density lipoprotein|LDL]] ("bad cholesterol").
:In any case, you're best off just asking your doctor or cardiologist what changes or benefits are likely to accrue from the specific changes you've made to your own, unique lifestyle. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 18:22, 3 February 2007 (UTC)
:: I don't know the answer to your question, but let me just say: kudos on the positive changes you've made! Keep with it! —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 18:29, 3 February 2007 (UTC)
== Do rats have spleens? ==
?
Don't you ? We're all mammals, ain't us ? --[[User:Harvestman|<font color="blue"> DLL </font>]] <sup>[[User talk:Harvestman |<font color="green"> .. T</font>]]</sup> 18:52, 3 February 2007 (UTC)
:I read that rats don't have bladders, so there might be other differences too. --[[User:84.69.30.24|84.69.30.24]] 19:26, 3 February 2007 (UTC)
::Rats have bladders. [[User:Chickenflicker|Chickenflicker]]---[[User talk:Chickenflicker|♣]] 19:28, 3 February 2007 (UTC)
:There's a diagram and a discussion of rat dissection here: [http://www.biologycorner.com/bio3/rat_head.html]. Rats do indeed have bladders, as well: [http://www.google.com/search?hl=en&safe=off&c2coff=1&q=rat+bladder&btnG=Search]. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 19:31, 3 February 2007 (UTC)
::Sorry. I've clearly been misinformed. It was an article in the newspaper about [[ratcatching]] where it was stated by a ratcatching expert that rats do not have bladders and hence constantly dribble piss behind them wherever they go to mark a trail for other rats to follow. --[[User:84.69.30.24|84.69.30.24]] 19:36, 3 February 2007 (UTC)
:Rats don't have [[gallbladder]]s. Maybe that is the source of confusion. --[[User:Joelmills|Joelmills]] 19:39, 3 February 2007 (UTC)
::....and ratcatchers have a wicked sense of humour. (At least, they're usually portrayed that way.)--[[User:Shantavira|Shantavira]] 09:12, 4 February 2007 (UTC)
== Question about pets and domestication ==
What's the difference between a tame pet and a domesticated pet? This comes up a lot on the birdkeeper forums and people actually have big arguments about it. Why would a [[cat]] be considered a 'domestic' pet while a [[cockatoo]] (for example) would be referred to by avian science people as a 'tame' pet? Is a budgie 'tame' or 'domesticated'? --[[User:84.69.30.24|84.69.30.24]] 19:25, 3 February 2007 (UTC)
:If you take a look at the article on [[domestication]], it says that [[Budgerigar|budgies]] are considered domesticated. "These species or varieties are bred and raised under human control for many generations and are substantially altered as a group in appearance or behaviour." As for cockatoos, [[Domestication#Degrees_of_domestication|the same article]] would probably put them in the category of "raised commercially" or "semidomesticated" rather than fully domesticated. [[User:Chickenflicker|Chickenflicker]]---[[User talk:Chickenflicker|♣]] 19:47, 3 February 2007 (UTC)
== How should you heat up an embryo? ==
I have a curiosity about how can embryos be defrosted from the fridge prior to being implanted to avoid that the water present expands thus damaging it. Can you heat it rapidly without burning the specimen?20:09, 3 February 2007 (UTC)
:I'd just let it warm up slowly, or in luke warm water - I think your question/my question should be "how can an embryo be frozen without causing frost damage from the ice crystals that will inevitably form" - the same goes for sperm.[[User:213.249.232.136|213.249.232.136]] 20:12, 3 February 2007 (UTC)
:Our article on [[cryopreservation]] gives a good overview of the challenges associated with freezing (and thawing) viable tissue and cells. [[Cryoprotectant]]s are chemicals which are added to cells at the time they are frozen; these chemicals typically discourage the formation of ice crystals which would otherwise puncture and kill cells.
:Thawing most frozen tissue or cells is actually a very straightforward process. There are two key goals in thawing. First, one wants to warm the tissue fairly rapidly through the temperature range where ice crystals are most likely to form; this runs from roughly -50°C to -15°C, give or take. Second, you want to wash off or dilute out the cryoprotectant. (Prolonged exposure to cryoprotectants will kill a warm cell.)
:Accomplishing these goals is generally straightforward. Frozen specimens are normally in glass or plastic tubes or vials. They can be warmed rapidly by immersion in a body-temperature (37°C) water bath; this thawed solution can then be diluted to reduce the concentration of cryoprotected to below toxic levels. For thawing small volumes, rapid warming and dilution can be accomplished by directly adding warm liquid to the frozen-solid sample. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 21:27, 3 February 2007 (UTC)
::[[Dimethyl sulfoxide|DMSO]] is commonly used for cryopreservation of cell lines...but I'm not sure if it's used for embryos... -- [[User:Scientizzle|Scientizzle]] 07:28, 4 February 2007 (UTC)
== Scarlet Fever ==
I am doing a report in science on an infectious diseases caused by bacteria. I picked scarlet fever. Please tell me all that you can!!!!!!!!!22:44, 3 February 2007 (UTC)
:Have a look at [[scarlet fever]] and [[Streptococcus pyogenes]], the latter being the species of bacteria that causes the disease. --[[User:Diberri|David Iberri]] ([[User talk:Diberri|talk]]) 22:46, 3 February 2007 (UTC)
== Is FM radio lossless? If not, what bitrate is it at? ==
Hello, my question is concerning the audio quality of FM radio. Does the transmission of the sound through the air bring the quality down? Do radio stations load up lossy files on their playlists, like 128 kb/s mp3 files? Basically, what bitrate would be comparable to the quality of FM radio on the receiving end/through my stereo? Thanks! [[User:NIRVANA2764|NIRVANA2764]] 23:11, 3 February 2007 (UTC)
:Its complicated to say, as it will depend upon the audio codec imployed, in the UK DAB broadcasts at 160 kb/s IIRC, via a form of MP2 encoding, with the speech only networks at a lower 128 kb/s and Radio 3 (classical music) at 192 kb/s. It is suggested that 192 kpbs is needed to give high quality audio broadcasts.
:For more info checkout the [[Digital Audio Broadcasting]] page, more specificaly [[Digital Audio Broadcasting#Criticisms of DAB|this section.]]
:There are other issues of course - often audio will sound different between a CD, radio and television broadcast, and if you are used to a particular version of a song then even though the other is at a higher rate of transmission it may still sound worse! --[[User:NeilTarrant|Neo]] 23:31, 3 February 2007 (UTC)
::Er... Traditional FM radio uses a purely analog modulation method (ignoring some of the sub band extensions). You can't talk about it in terms of "bit rate" (as you could with digital modulation schemes like [[PSK]] and [[OFDM]]). Your usage of "lossless" seems to be in the sense of digital audio compression methods, which is simply irrelevant here. The article on [[frequency modulation]] proper provides some insights on maximum bandwidth, drift, SNR, etc. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-04T03:30Z</code>
::FM Radio has a Signal to Noise ratio and is not digital. 1 bit corresponds to roughly 6 db (6 db is double signal level, 1 bit in base 2 is double). Original CD quality is 16 bits which corresponds to about 96db of S/N. Bit rate corresponds to the frequency range. IIRC, CD's are about 24KHz of range which for Nyquist is 48 KHz. So a CD plays 16 bits at 48 KHz => 768 kb/s. You can trade frequency or S/N to reduce this number and compression does it smarter than just the baseline cut.
:: FM as implemented has a frequency range to 15 kHz (30 KHz Nyquist) and I believe the noise floor give about 60dB of dynamic range (~10 bits). Note that this is best case in FM and in practice is worse than this. That's 30*10 or 300 Kbps for Nyquist sampling to Digitally recreate the best possible fidelity of FM analog. --[[User:Tbeatty|Tbeatty]] 07:02, 4 February 2007 (UTC)
:::A fair point - but FM is analogue - therefor the resolution (eg CD resolution is 16bit) could be considered infinite..(not quite true)
:::: Resolution, whether it's digital or analog, is expressed as signal-to-noise ratio. Quantization error (the error between "infinite" analog and discrete digital) can be expressed as noise. In fact, moving the quantization error out of the baseband frequency is how 1-bit, oversampling works. It is entirely accurate to compare digital resolutions with S/N and analog with S/N. There is no additional resolution because of the continuous nature of the analog signal. That portion of continuity that distinguishes iteself from the digital portion is unrealizable signal that is lost in the noise. Analog FM is not infinite resolution because there is a finite noise floor that limits it. Currently that noise floor is 60 dB and that is an equivalent noise floor to 10 bits. You have to think in the frequency ___domain (for both anaolog and digital) to understand the mathematics that proves this. [[Fourier Transform]]s and the [[Discrete Fourier Transform]]/[[Fast Fourier Transform]] is the mathematics required for the analogue and digital respectively. --[[User:Tbeatty|Tbeatty]] 19:22, 4 February 2007 (UTC)
:FM quality depends critically on reception conditions as it is an analogue signal - in general a good signal strength of FM radio would produce audio quality comparable to analogue records or cd's - but not quite as good - better than cassette tape though.
:The weaker the signal the poorer the sound so yes - transmission affects quality.
:I'd guess that FM radio stations don't usually transmit MP3 files - most likely they use CD's or another digital source such as DAT. However [[audio level compression]] is common on FM - resulting in a percieved loss of quality.
:I wondered if you were thinking about [[DAB]] - digital radio - apparently a FM gives a comparable quality of sound as 192kbit/s digital radio as a best case - in reality it's probably a lot less.[[User:87.102.7.169|87.102.7.169]] 10:23, 4 February 2007 (UTC)
== [[Cold fusion]]? real? ==
How come wikipedia's article on Cold Fusion is written from the POV that Cold Fusion is real? Isn't it odd for an article to be writtin from such an obscure perspective?--[[User:71.249.19.4|71.249.19.4]] 23:43, 3 February 2007 (UTC)
:Could you quote an example of this alleged bias? I looked it over just now and it seems fine, but of course I could have missed something. Anyway, the reference desk is not for questions about Wikipedia. Next time bring it up on the talk page. —[[User:Keenan Pepper|Keenan Pepper]] 00:39, 4 February 2007 (UTC)
::Actually, the Reference Desk ''can'' be for questions about Wikipedia. One of the Reference Desk's primary purposes is to help the project, and one way it does this is by assisting editors in their research. (There's a fine example [[#Dopamine_reuptake_inhibitor.7C_Antidepressants_.7C_NEED_REFERENCES|just below]].) —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 01:05, 4 February 2007 (UTC)
:IMO, it does seem to be a bit biased towards cold fusion, but nothing blatant enough for a non-expert to object to. It would take someone really knowledgeable in the field to do that. [[User:Clarityfiend|Clarityfiend]] 03:16, 4 February 2007 (UTC)
::The original cold fusion claims reportedly lacked the emission of neutrons sufficient for the energy claimed. As I recall, the energy production was chalked up to normal electrochemical processes and inadequate process control. Reading this article, I get more of an impression of there being fusion than the earlier analyses implied. I believe there have ben recent reputable claims of cold fusion, but in processes which could never be energy sources, but still useful as neutron sources. Any nuclear engineers out there? [[User:Edison|Edison]] 05:14, 4 February 2007 (UTC)
:I too agree that there is no noticable bias - to a non expert - and in terms of the info. in the article. It is possible that information/papers against cold fusion occuring are underepresented and evidence for is over represented... But in terms of the writing style I can see no bias.
[[User:87.102.35.119|87.102.35.119]] 12:57, 4 February 2007 (UTC)
:: The perceived "bias" may be that the article does not come out and say "Cold fusion is wrong! R O N G wrong! [[Martin Fleischmann|Fleischmann]] and [[Stanley Pons|Pons]] were charlatans and frauds! It was all a hoax!" But of course, that would be just as badly POV, in the other direction. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 13:40, 4 February 2007 (UTC)
:::Now, now. Cool down; don't go nuclear on us. [[User:Clarityfiend|Clarityfiend]] 17:19, 4 February 2007 (UTC)
= February 4 =
==Water as a yellow solid?==
I left the lid on a pot of boiling water and came back thirty or so minutes later. Aside from my being an idiot, here's what I found: the lid had a thin layer of yellow power over in, and little balls of yellow powdery substance had formed in the pot. There was an intense smell, and the pot was hot enough to vaporize the hot water I poured on it on contact. Should I contact poison control? Is the pot safe to use again? And most importantly, what the heck just happened? --[[User:162.83.149.125|162.83.149.125]] 18:46, 4 February 2007 (UTC)
:What's the material the pot is made of, and what do you usually use the pot for? — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 20:29, 4 February 2007 (UTC)
::It sounds like [[sulfur]], but sulfur isn't water soluble. On the other hand, if it's water from the tap, there maybe lots of sulfur within the water (because it comes from the ground). Boiling water is one of extracting elements and compound within it.
::I would call poison control, just to be on the safe side.--[[User:Honeymane|<font color="red" face="Old English Text MT, Papyrus">Honeymane</font>]]<sub>[[User_talk:Honeymane|<font face="Klingon, QuigleyWiggly">Heghlu meH QaQ jajvam</font>]]</sub> 20:40, 4 February 2007 (UTC)
Same here call poison control to check it out If it is toxic and was tap water then you need to bring it to the attention to the city you live in . but before you do that check your pipes (if you are using metal pipes then its probably rust) [[User:Maverick423|Maverick423]] 23:26, 4 February 2007 (UTC)
: You didn't happen to take a picture of the pot and these yellow balls, did you? —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 23:41, 4 February 2007 (UTC)
:It sounds like [[gunge]] to me (it don't think the wikipedia article does the word justice) - it could be vaporised organic matter from the bottom of the sauce pan that condensed on the lid. The yellow stuff is not water! [[User:Graeme Bartlett|GB]] 23:57, 4 February 2007 (UTC)
== [[Dopamine reuptake inhibitor]]| Antidepressants | NEED REFERENCES ==
Q1. ''I am looking for references to back up this paragraph:''
In general, the abuse potential of DAR inhibitors depends on how they affect the pattern of dopamine release and reuptake. Compounds that inhibit reuptake and also induce release of dopamine, such as [[methamphetamine]] or [[phenmetrazine]], or compounds that inhibit reuptake but have no effect on release, such as [[cocaine]] or [[methylphenidate]], tend to be [[addictive]] drugs with potential for abuse in humans. {{fact}} On the other hand, compounds that inhibit reuptake but also inhibit release of dopamine, such as [[bupropion|Wellbutrin]] and [[vanoxerine]], have mild stimulant effects and little abuse potential, and can be used to treat stimulant addiction. {{fact}}
''I would appreciate the references provided. Thank you.'' --[[User:Parker007|Parker007]] 07:10, 29 January 2007 (UTC)
:http://www.drugabuse.gov/NIDA_Notes/NNVol12N3/Compounds.html mentions the addictive properties, in relation to preventative treatments; http://www.medscape.com/viewarticle/418525 mentions addiction's reuptake patterns in general, and then in relation to [[methadone]] and some othe B-drug that I forgot the name of. All provided by [http://www.google.com/search?q=reuptake+inhibitor+addiction&hl=en&start=10&sa=N this] Goog search. [[User:V-Man737|V-Man737]] 07:10, 30 January 2007 (UTC)
::''Please explain how the above references are actually related to:'' "On the other hand, compounds that inhibit reuptake but also inhibit release of dopamine, such as [[bupropion]] have mild stimulant effects and little abuse potential." ''I would much appreciate a reply. Thanks.'' --[[User:Parker007|Parker007]] 07:30, 30 January 2007 (UTC)
:::Oh - now I see the first article doesn't mention Bupropion specifically... hrmph. Perhaps the sentence in the article should be changed to match the source, rather than whoring up a source to fit an exact claim? I'm sorry for the scanty help, it's past my [[bedtime]]... [[User:V-Man737|V-Man737]] 07:44, 30 January 2007 (UTC)
*On the other hand, compounds that inhibit reuptake ''but also inhibit release of dopamine'', such as [[bupropion|Wellbutrin]] and [[vanoxerine]], have mild stimulant effects and little abuse potential, and can be used to treat stimulant addiction. {{fact}}
*I believe the above statement, I just want a reference. Please? --[[User:Parker007|Parker007]] 00:05, 4 February 2007 (UTC)
:Please say which part of the statement you want a reference for.[[User:87.102.7.169|87.102.7.169]] 10:57, 4 February 2007 (UTC)
::Its "but also inhibit release of dopamine" --[[User:Parker007|Parker007]] 02:05, 5 February 2007 (UTC)
:Searching for 'zyban' another name for bupropion - gives many references saying that it can be used to treat nicotine addition.
:Searching for 'vanoxerine addiction' turns up numerous references saying that it may be useful for cocaine addiction eg http://dmd.aspetjournals.org/cgi/content/full/29/9/1216 (note this says it is a dopamine reuptake inhibitor..I haven't done a full search for the best example.
:Is this what you wanted references for or did you want a reference that says specifically that they inhibit dopamine release? If so see below.[[User:87.102.7.169|87.102.7.169]] 10:47, 4 February 2007 (UTC)
::((Also the statement 'have little abuse potential' could be construed as [[weasel words]] when the articles on Bupropion clearly state that they have been abused by some patients.. Why not just re-write to match the facts.))[[User:87.102.7.169|87.102.7.169]] 11:10, 4 February 2007 (UTC)
::From what I can find it seems that Vanoxerine inhibits '''other drug induced''' dopamine release - eg it inhibits the action of dopamine release by another drug - so that's subtly different. here http://www.mdma.net/dopamine/vanoxerine.html a 60% reduction in the dopamine release under the conditions described if I've read correctly.
::Here's a reference that states that bupropion decreases spontaneous dopamine release http://www.cocaine.org/dopamine/efflux.html [[User:87.102.7.169|87.102.7.169]] 11:22, 4 February 2007 (UTC)
Thank you very much friend; (I am looking for reference that states Wellbutrin/bupropion inihibits the release of dopamine; as there is already a reference in the article [[bupropion]] regarding it inhibits reuptake of dopamine.) from the last reference I got this:
{{cquote|
[[Release of dopamine via the human transporter]]
by Eshleman AJ, Henningsen RA, Neve KA, Janowsky A., Research Service,
Veterans Affairs Medical Center, Portland, Oregon.
Mol Pharmacol 1994 Feb;45(2):312-68
ABSTRACT
A human dopamine transporter [[cDNA]] was cloned and transfected into COS-7 cells, a cell line that lacks vesicular storage and release mechanisms. Cells expressing the dopamine transporter acquired the capacity to take up and release dopamine via the transporter. Ionic conditions that stimulate inside-out transport in vivo, such as depolarizing concentrations of K+ or low concentrations of extracellular Na+, were found to stimulate Ca(2+)-independent release of [3H]dopamine from transfected COS-7 cells. Dopamine re-uptake inhibitors had one of three effects on transporter-mediated efflux. '''Some drugs,''' in addition to inhibiting re-uptake, '''inhibited spontaneous release of dopamine.''' '''Drugs in this class included''' mazindol, GBR-12935, '''bupropion''', nomifensine, and benztropine. All of the drugs with the potential for abuse by humans either enhanced release (methamphetamine, amphetamine, and ethanol) or had no effect on release (phencyclidine, cocaine, and WIN 35,428). The ability to define classes of uptake blockers based on their effects on human transporter-mediated dopamine efflux may lead to the identification of structural features of the transporter that differentiate abused from nonabused drugs.}}
--[[User:Parker007|Parker007]] 02:16, 5 February 2007 (UTC)
[[Wikipedia:Reliable_sources]] --[[User:Parker007|Parker007]] 11:58, 5 February 2007 (UTC)
== On the subject of cockatoos... ==
I've never owned a [[cockatoo]] myself but having spoken to cockatoo owners in real life and online, I have been told that peculiarly amongst pet birds, tame cockatoos (particularly [[Umbrella Cockatoo]]s and [[Moluccan Cockatoo]]s) actively enjoy being picked up and cuddled and will continuously pester their owners to be held like babies (screeching and screeching until they get their own way - and they can be *loud*). Now, as someone with experience keeping parrots, I know that the birds generally *hate* being picked up, especially if their wings are restrained. Anyone know what the deal is with cockatoos? More than one owner has reported to me that these birds behave like this 'out of the box', with little in the way of training required, like it comes completely naturally to them to enjoy being held by a potential predator. I find it a bit odd. --[[User:Kurt Shaped Box|Kurt Shaped Box]] 00:24, 4 February 2007 (UTC)
:Not a cockatoo, but our [[sun conure]] loves being cuddled, climbing inside clothing, and the like.
:[[User:Atlant|Atlant]] 13:39, 4 February 2007 (UTC)
:: I can't answer the "why", but my sister Suzy had a cockatoo (looked exactly like [[:Image:Buberel White parrot.jpg|our picture]]), and I can confirm all of the above. Coral would spend as much time on my sister's shoulder as possible, even in the shower, lifting first one wing and then the other as my sister turned so that the bird could wash under both. Coral was also deeply sexist, vastly preferring the company of women, and hissing whenever I or Suzy's husband or any other man got near.
:: The arrival of first Suzy's husband, then their dog, then their first child -- all put deeper and deeper strains on Coral's emotions. It got so bad that on the day when I was at their house babysitting the first child while Suzy was at the hospital delivering her second, Coral walked into the room and started nuzzling up against my leg; that's how desperate the bird was for affection in what she seemed to see as her abandonment by Suzy. Eventually she had to give Coral away, to a bird farm where Coral found another cockatoo to fall in love with instead of a human, and was much happier after that.
:: I'll have to ask Suzy if she can give any insight into why cockatoos are like this. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 14:33, 4 February 2007 (UTC)
== Speed of Light ==
What is the speed of light, and how can we tell? It goes too fast to just use a speed gun on. [[User:71.219.43.14|71.219.43.14]] 01:32, 4 February 2007 (UTC)
:THe speed of light is approximately 300 000 km/s or 186 000 miles/s. Have a look at the [[speed of light]] article for more information. The article also gives a description of how these numbers were reached. The method used is to reflect a beam of light off an object and time how long it takes. [http://www.colorado.edu/physics/2000/waves_particles/lightspeed_evidence.html This site] also gives a quick explanation. - [[User:Akamad|Akamad]] 01:44, 4 February 2007 (UTC)
::The speed of light is different in different media. What is often colloquially referred to as "the speed of light" is actually the speed of light in a perfect vacuum. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-04T03:21Z</code>
:::Quite right, but the speed of light in air is practically the same. It's slower than speed of light in vacuum by only about 100 km/s or 60 miles/s, wihch is less than the roundoff error in the approximate numbers quoted above.
:::Not incidentally that a "speed gun", mentioned by the original poster, is a device that's only possible because we know what the speed of light is. (Well, it uses radio waves, but the speed is the same.) --Anonymous, February 4, 05:02 (UTC).
::::And that brings up another way to measure speed. Permittivity can be measured from capacitance and the relationship to the speed of light is known, therefore, two paths (one free space, the other through a dielectric) could be set up and the difference in arrival times measured. This will reduce measurement error as it is common to both measurements. Just a guess. --[[User:Tbeatty|Tbeatty]] 08:30, 4 February 2007 (UTC)
== The sun ==
How old is the sun? [[Nucleocosmochronology]] has a different answer than [[sun]]. Also how does Nucleocosmochronology tell the age? The article is vague. [[User:71.219.43.14|71.219.43.14]] 02:01, 4 February 2007 (UTC)
:Huh? Both articles say the Sun is 4.57 billion years old, give or take. [[User:Clarityfiend|Clarityfiend]] 05:13, 4 February 2007 (UTC)
== Phylogenetic tree ==
Hi!
Would anyone know where i could find a phylogenetic tree of life, containing all groups, made in a nice and clear way, and up-to-date? It's to print and use as a poster. It can be in a book, article, website,... The best would be if it could have little drawings for species examples, derived characteristics, and maybe other features like that.
Thanks!! <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/84.55.198.228|84.55.198.228]] ([[User talk:84.55.198.228|talk]]) 02:39, 4 February 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
:Try the [http://tolweb.org/tree/ tree of life] project. --[[User:JWSchmidt|JWSchmidt]] 23:31, 4 February 2007 (UTC)
:Look at [[Phylogenetic_tree]], but the images here are more useful as a page in a book rather than having the amount of detail presented on a poster. [[User:Graeme Bartlett|GB]] 23:50, 4 February 2007 (UTC)
Given issues with copyright from other sources it might be a good idea to construct your own..[[User:87.102.8.103|87.102.8.103]] 12:40, 5 February 2007 (UTC)
== Methadone and Anestesia? ==
Is it safe to be a methadone patient (receiving methadone on a daily basis) and undergo surgery with a general anesthesia such as [[Propofol]]? I'm not asking for any kind of advice, diagnosis, nor would I have surgery while being on any kind of drug without first discussing it with my Doctor. I just would like to know if there are any problems or interactions with general anesthesia that is most commonly used and methadone. I'm sure there are tons of medications used, but there must be one that is commonly used such as [[Halothane]] or [[Propofol]]. Thanks
[[User:Sniggity|Sniggity]] 05:54, 4 February 2007 (UTC)
:I think you are asking a question that could pretty much only be answered by a qualified [[anesthetist]], I don't know if there are any that read this board. I'm sure methadone patients have undergone surgery but as to how safe or which anesthetic is used, I have no idea. [[User:Vespine|Vespine]] 10:58, 4 February 2007 (UTC)
== Fin Dimensions ==
Greetings... For a rated average power of 3 KW and frequency range of DC to 3.0 GHZ, what fin dimensions would I require in my heat sink??? As the coolant I would use Silicone oil, capacity of 1 Gallon Load resistor would be of 10-12 inches and Diameter would be 12-15 mm. All this is for building a RF Load as a part of engineering curriculum. <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/203.187.198.42|203.187.198.42]] ([[User talk:203.187.198.42|talk]]) 06:45, 4 February 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
: Sounds like homework. But for starters, don't you need to know the temperature requirement of the load resistor or temp limit of the oil or other components? --[[User:Tbeatty|Tbeatty]] 07:08, 4 February 2007 (UTC)
::We absolutely need to know the max allowable temperature of the oil and the resistor, and also the ambient temperature (how hot of a room will it be in) and whether there is air circulating or not. Also, do you want it to be able to run continuously, 24/7, or will it have , say, a 50 % duty cycle, or be rated for 10 minutes of operation. As a refinement, will it be in the sun or in the shade, and if in the sun, what color will it be. As a thought experiment, I compare it to a distribution transformer with say a 4% loss at full load. Your 3 KW heat dissipation would then require about the same radiator as a 60 kilowatt transformer, which is HUGE compared to a 1 gallon paint can. Another comparison: [http://michaelbluejay.com/electricity/howmuch.html] says an electric range burner uses about 800 watts, fso your device would need enough radiationg surface to siddissipate the heat of almost 4 range burners. 3000 amps is 12.5 amps at 240 volts, so you have a very large amount of heat to dissipate. I would go with a cooling fan. Your device wilkl heat up like two 4 slice toasters per the site listed. To avoid overheating you will need a large area of copper or aluminum fins connected to the can in such a way heat is efficiently transferred (soldered? Or tight fit with the special grease they use on top of PC chips to connet them to the heatsink.? (Someone who took a course in thermal engineering, should the radiator fins be painted black? And there will still be a tendency for the oil to overheat and expand, if you only have convection inside the can, so the top of the resistor might get excessively hot. Could you install a thermometer or thermocouple or an oil temp thermometer? [[User:Edison|Edison]] 23:23, 4 February 2007 (UTC)
Firstly, I must apologize. I will operating at 600 Watts average and not 3KW which I errenously mentioned. Secondly, Thanks for responding. The max. allowable temp. of the oil is 250 degree Celsius and the resistor of about 200 degree celsius. NO, it wouldn't run 24/7 and ambient temp. would be 30-40 degrees depending on the climate.
==Names for [[bioluminescence]] in the ocean==
Are there any common (non scientific) names for [[bioluminescence]] in the ocean? (Note that Milky Sea is thought to be caused by bacteria, not by bioluminescencing plankton.) Thanks for your help. [[User:S.dedalus|S.dedalus]] 06:47, 4 February 2007 (UTC)
:There is in [http://no.wikipedia.org/wiki/Morild Norwegian], [http://da.wikipedia.org/wiki/Morild Danish], [http://de.wikipedia.org/wiki/Meeresleuchten German], and possibly also [http://tr.wikipedia.org/wiki/Yakamoz Turkish]. My Norwegian-to-English dictionary has no entry for the word. [http://google.com/translate_t Google translate] translates Meeresleuchten (German) to "Sea lights", but that is simply a literal translation, I have no idea whether it's actually used. According to the [http://de.wikipedia.org/wiki/Meeresleuchten German wikipedia], these "sea lights" play a key role in [[Jim_Button_and_Luke_the_Engine_Driver|this children's novel]], so if anyone's got a copy, they might check how it has been translated. --[[User:NorwegianBlue|NorwegianBlue]]<sup>[[User_talk:NorwegianBlue| <u>talk</u>]]</sup> 15:42, 4 February 2007 (UTC)
==Wormholes in 3d space==
Wormholes are commonly represented in images explaining them as 2d holes or tunnels, however, because space is 3d, and not 2d, I am having difficulty visualizing. How are things like wormholes represented in 3d, rather then the 2d represention. (like the warping of space time due to a massive object like the sun is shown as a ball on a plane).--[[User:Honeymane|<font color="red" face="Old English Text MT, Papyrus">Honeymane</font>]]<sub>[[User_talk:Honeymane|<font face="Klingon, QuigleyWiggly">Heghlu meH QaQ jajvam</font>]]</sub> 08:15, 4 February 2007 (UTC)
:Notice how it takes 3-D to "visualize" the bending of 2-D space. So it will take at least 4-D to visualize the bending of 3-D space. Can you visualize in 4-D? --[[User:Spoon!|Spoon!]] 10:45, 4 February 2007 (UTC)
We see in 4D all the time (no pun intended), its just 3D in relation to time (relative movement)...
The reason that it is difficult to visualise could be that a worm hole is impossible in 'conventional' 3D [[euclidean space]] - (I'd imagine that you visualise things in 3D euclidean space - I do anyway). I could say it's difficult to imagine because they don't exist...[[User:87.102.35.119|87.102.35.119]] 13:18, 4 February 2007 (UTC)
== developement of SPRING stl? ==
<email removed> <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/12.72.54.244|12.72.54.244]] ([[User talk:12.72.54.244|talk]]) 12:52, 4 February 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
Please try to write a coherent question.. Did you mean 'can I have more info on the development of [[spring steel]]? (if so you may wish to look at the [[crucible steel]] and [[puddling process]] Please clarify?[[User:87.102.35.119|87.102.35.119]] 12:59, 4 February 2007 (UTC)
== ARUUN SINGH ==
what are the benefits of swallowing human semen? <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/221.134.58.58|221.134.58.58]] ([[User talk:221.134.58.58|talk]]) 14:16, 4 February 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
:[[Cecil Adams|The Master]] has already addressed one aspect of this question; see [http://www.straightdope.com/classics/a1_054.html here]. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 14:50, 4 February 2007 (UTC)
: Less messy than any other method of oral evacuation? [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 07:48, 5 February 2007 (UTC)
: And of course the possibility of gratitude if the donor is of the mind that any other method is some kind of insult.
== Bird identification and image request ==
[[Image:Bird.parts.jpg]]
Hi, does anyone recognize this bird? Could a better image that's more suitable for printing be made? (It wouldn't have to be the same species, but I wonder if finding a bird with all the features would be easy.) Thank you. :) --'''[[User:Kjoonlee|Kjoon]]'''[[User talk:Kjoonlee|lee]] 14:57, 4 February 2007 (UTC)
:Is it the dreaded caption bird, who skewers would-be predators with sharp words, like a verbal porcupine? [[User:Clarityfiend|Clarityfiend]] 19:07, 4 February 2007 (UTC)
:::I too would like to point out it's the green diagram bird (''birdus diagrammaticus'') - seriously it looks a lot like a finch, or tit - a [[passerine]]. I doubt it would be difficult to find and alternative - as long as the species has wing bars your in luck.[[User:87.102.8.103|87.102.8.103]] 11:17, 5 February 2007 (UTC)
::Yes, it's almost certainly a composite made up for the purpose of labelling. See [[insect]] for a really weird composite insect!--[[User:Shantavira|Shantavira]] 19:43, 4 February 2007 (UTC)
:Heh. :) The original uploader has responded to my inquiry.
::''Hi, this image was meant to describe the most important characteristics to the anatomy of a common (passerine) bird, and not to represent an actual species. However, this fantasy bird was loosely based on the anatomy of the [[chaffinch]] (although the colors do not match). I do not have a higher resolution version of this image, nor do I have an unlabeled version. Sorry. :-(''
:So I guess that's enough info to get someone to come up with a better image.. :) --'''[[User:Kjoonlee|Kjoon]]'''[[User talk:Kjoonlee|lee]] 15:06, 5 February 2007 (UTC)
== history of nitroglycerine as a medicine for heart pain ==
Hello- I am writing a historical novel set in the 1880's.
One of my characters has heart pain (angina), and takes nitroglycerine for it. Is this appropriate for the times? I know that it had been discovered, and was being used as an explosive, but when did it start being used as a medicine? Thank you for your help.
Sincerely, [[User:Irene Wolf|Irene Wolf]] 16:50, 4 February 2007 (UTC)
:I am not sure myself, but I think the article, [[Glyceryl trinitrate (pharmacology)]] may have what you are looking for. - [[User:Dozenist|Dozenist]] <font color="darkgreen" size="1">[[User talk:Dozenist|talk]]</font> 16:55, 4 February 2007 (UTC)
[[William Osler]] mentions it in his 1892 Principles and Practice of Medicine as an alternative treatment to [[amyl nitrite]], which either he preferred or was the standard treatment of the time. The wording might be interpreted that nitroglycerin was relatively new and not universally considered standard. [[User:Alteripse|alteripse]] 17:11, 4 February 2007 (UTC)
:You're in luck. According to [http://www.answers.com/topic/nitroglycerin], it was first used for angina in 1879. [[User:Clarityfiend|Clarityfiend]] 17:56, 4 February 2007 (UTC)
::Off on a slight tangent but the topic reminded me of [http://darwinawards.com/stupid/stupid2001-24.html this] Darwin Award story... --[[User:Kurt Shaped Box|Kurt Shaped Box]] 18:58, 4 February 2007 (UTC)
:::That raises another question. Who thought this up? Let's treat heart pains with...a dangerous explosive. An ancestor of [[Dr. Kevorkian]]? [[Monty Python]]? [[User:Clarityfiend|Clarityfiend]] 20:12, 4 February 2007 (UTC)
[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10779131&dopt=Abstract A short history of nitroglycerine and nitric oxide in pharmacology and physiology]. --[[User:JWSchmidt|JWSchmidt]] 23:17, 4 February 2007 (UTC)
== Dioxygen leak? ==
Is it true that a major dioxygen leak could have drastic effects on local plant and animal life? Is it true that leaks of this type have occured all over the country leaving very high dioxygen levels in the atmosphere? Isn't this hazardous?
:See [[dioxygen]]. See also [[dihydrogen monoxide]]. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 19:59, 4 February 2007 (UTC)
:It's definitely a fire hazard. And I've heard that everyone who breathes it, expires. [[User:Clarityfiend|Clarityfiend]] 20:13, 4 February 2007 (UTC)
::Dioxygen is a good oxidizer, and therefore can be very dangerous in the presence of a fuel and ignition source. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-04T20:35Z</code>
::But it is nothing compared to [[dioxin]] which comes from [[Polychlorinated biphenyl|PCB]]. [[User:Edison|Edison]] 23:01, 4 February 2007 (UTC)
:: Well that's true, even literally! No one lives forever!
:::Funnily enough, our [[atmosphere]] is 20% dioxygen! —<span style="font: 11pt 'palatino linotype'">'''''[[User:LestatdeLioncourt|<font color="green">Lestat</font><font color="black">deLioncour</font>]][[User_talk:LestatdeLioncourt|<font color="black">t</font>]]'''''</span> <small>14:46, 5 February 2007 (UTC)</small>
mmmm mmm smell that beautiful dioxygen! i dont know man but for some reason i think you need to double check your sources lol you might find the extra info useful that is if you havent done so already. [[User:Maverick423|Maverick423]] 16:02, 5 February 2007 (UTC)
Dioxygen is just oxygen <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:88.109.41.162|88.109.41.162]] ([[User talk:88.109.41.162|talk]] • [[Special:Contributions/88.109.41.162|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
:No, dioxygen is O<sub>2</sub>. There is a difference between a molecule and an element, even if we are being silly and pedantic about it. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-06T06:39Z</code>
== Free radical bromination of ethane ==
I already looked at the articles related to this subject, (free radical halogenation, and ethane) but I'm not sure I understand the initiation, propagation, and termination mechanisms behind it. Is there a visual examination for the free radical bromination of ethane that anyone knows of?
:[[free radical halogenation]] has the answers - could you be more specific as to what you don't understand/want explaining.
:Also I don't understand what you mean by 'visual examination' - do you mean a page with images to explain the process, or a way visually of telling if the process is occuring or something else?[[User:87.102.8.103|87.102.8.103]] 11:21, 5 February 2007 (UTC)
== Can't afford the real thing, so I make doo with sham poo ==
When my shampoo runs low, I leave the bottle turned over, so the last dregs accumulate at the cap. But I've noticed that it seems to eat the plastic in the cap (the color runs into the shampoo). What causes it? Is this harmful? [[User:Clarityfiend|Clarityfiend]] 20:20, 4 February 2007 (UTC)
:Wow, what are you putting in your shampoo?! '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 14:30, 5 February 2007 (UTC)
i think your using bleach as shampoo... nah just kidding its that thing that helps clean your hair thats causing that. its not harmful (unless swallowed ((or left on your hair for a long time))). [[User:Maverick423|Maverick423]] 16:04, 5 February 2007 (UTC)
Lots of the chemicals in shampoo disolve other chemicals, so it could be one of these causing this:(
Some of these chamicals also disolve the proteins that hair is made from, so it probably isn't a good idea to wash with it at all:(
:It's a nationally-marketed brand, not some weird generic glop. Oh well, I suppose the company may be saving money by using a cheaper, less durable plastic for the top. [[User:Clarityfiend|Clarityfiend]] 22:03, 5 February 2007 (UTC)
== jaw injury ==
What is the likelihood that a serious injury to the upper jaw, would subsequently cause a person to be reported as a chronic drunk? Consider the effect upon motility of the tongue, and the distinct possibility of affecting the inner structures involving balance.
{{unsigned2|20:50, 4 February 2007|71.104.2.173}}
::''What is the likelihood?'' ?? Is that a serious question? What kind of answer do you want? The likely hood is unlikely? or, maybe a one in ten? Or do you want to discuss the various conditions? If it is dark and the observer is himself drunk then the likelihood is higher then if the subject is in an operating theatre being examined by physicians. ''Serious injury'' seems to imply some sort of pain and breakage if not bleeding, those are going to be hard to mistake for drunkenness. I work with a guy who has sclerosis and he was refused entry into a bar once because the bouncer thought he was drunk, no kidding.. So I guess it's not impossible. [[User:Vespine|Vespine]] 21:30, 4 February 2007 (UTC)
:Given that someone with a recent serious jaw injury would be either - bleeding or screaming in pain - I'd say it's unlikely. They'd probably also be pointing to their jaw as well and be saying something like 'I've got a serious jaw injury - please help me..' - whereas a chronic drunk would stink of beer, smell of urine and probably be singing 'auld lang syne'...[[User:87.102.8.103|87.102.8.103]] 11:25, 5 February 2007 (UTC)
It is phrased like a homework question. I feel sorry for the student-- if actually provided as cited, it is a question so poorly phrased that we are all guessing at the real intended question. My guess is that the teacher is asking, "An injury to what part of the vocal apparatus would produce speech that would sound like drunken slurring to most people." The answer is a stroke or an injury to the brain would be the best mimic, because most of us can readily tell the difference between defects of central speech processing and defects of articulation. If the answer is to be restricted to the area of the upper jaw, it would be an injury to efferent motor nerves controlling tongue, mouth and palate. Good luck to the student. [[User:Alteripse|alteripse]] 14:14, 5 February 2007 (UTC)
:Damage to the [[inner ear]], which is very possible in an upper jaw punch, could cause damage to the [[semicircular canal]]s, which measure the orientation of the head. Damage to the canals causes loss of balance and difficulty walking, just like alcohol. [[User:Smurrayinchester|<span style="color:#BB0055">Laïka</span>]] 21:25, 5 February 2007 (UTC)
:Well I suppose whatever had injured the upper jaw might also have caused other problems, like [[concussion]]. People with head injuries can be mistaken for being drunk, as occasionally happens in police stations and hospitals on Friday nights in town centres... [[User:Skittle|Skittle]] 23:17, 5 February 2007 (UTC)
== Fermi Problems ==
When I get fermi problems, do I have to use my "own basic knowledge and experience" or am I allowed to look stuff up? <small>I don't know how much cheese France consumes every year/day/month! How do I guess that? </small>--[[User:JDitto|JDitto]] 23:18, 4 February 2007 (UTC)
:One of the purposes of a [[Fermi problem]] is to get an idea of scale and the approximate magnitude of the answer, it is not intended to be that accurate. I don't know how many people live in [[France]] off-hand, but I might guess 20 million based on size relative to some US states and given Europe has a higher population density. The average person eats maybe a half-pound of cheese a week. 20 million people * 0.5 pounds cheese week/person = 10 million pounds per week, or roughly 1 million pounds a day, which is undoubtedly totally wrong, but I have some confidence that it isn't under 100 thousand per day, or over 10 million. On actually looking at the France article, my estimate is off by three times, but the magnitude of my estimate didn't change significantly. [[User:Atropos235|Atropos235]] 03:02, 5 February 2007 (UTC)
:Have you read our article on [[Fermi problem]]s? As that article explains, you typically work with just a bunch of guesses. Certainly you can't look up the final answer -- if you could, it wouldn't be a Fermi problem -- and for the intermediate numbers leading up to the answer, most are either educated guesses, or "basic knowledge and experience". (In the "number of piano tuners in Chicago" example in the [[Fermi problem]] article, the only quantity you could easily look up is the number of people in Chicago; all the rest of the numbers are pulled out of the air.) The point of the exercise is usually to come up with a quick estimate, without doing any research, and perhaps at the same time to discover which potential avenues of research might be used to obtain a more accurate (non-guessed) answer later. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 02:50, 5 February 2007 (UTC)
:[P.S. It occurs to me in light of recent debate that the Fermi problem approach -- pulling a bunch of numbers out of the air, and combining them with some basic knowledge and educated guesses -- is precisely what Wikipedia's [[WP:V|verifiability policy]] suggests we ''shouldn't'' be doing in answering questions on the Reference Desk... :-)]
::I just need to know what I'm allowed to look up. I know I'm not allowed to look up the answers, so I want to stay away from reading the article itself right now. Thank you so far, though.--[[User:JDitto|JDitto]] 05:37, 5 February 2007 (UTC)
::: Wait -- you're not allowed to read the articles on [[cheese]] or [[France]], or you're not allowed to read the article on [[Fermi problem]]??
::: I'd say the short answer is, no: for a proper Fermi solution you shouldn't look anything up. Background knowledge, armchair speculation, and erudite pontification only. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 12:37, 5 February 2007 (UTC)
::::Fermi problems are problems where you are not able to calculate the answer, given the proper information. You are allowed to look up whatever you want, but at the end you will have to [[estimate]] a plausible answer anyway. [[User:Mr.K.|Mr.K.]] [[User_talk:Mr.K.|(talk)]] 18:26, 5 February 2007 (UTC)
:I would say that a fermi problem should only include information known to you or easy to find and integral to the problem. so for the france one it seems fine to look up the pop of france. its a matter of effort and time not deliberate limitation of knowledge. [[User:Beckboyanch|Beckboyanch]] 02:44, 7 February 2007 (UTC)
Okay, this is what I got for the "France eating the Moon", looking up as many non-internet sources as possible:
*Earth's Mass: ''5.9 X 10<sup>24</sup> kg''
*Children's Astronomy Book: ''Earth is 50X bigger than the Moon''.
*Therefore: ''(5.9 X 10<sup>24</sup>) / 50 = 1.18 X 10<sup>23</sup> kg''
:*MAYO Food Guide Pyramid says that ''2-3 servings'' of milk group everyday.
:*Each serving = ''1 1/2 oz.'' of natural cheese
:*''1 oz = 28.35 g''
:*Therefore: ''2.5 X 28.35 = 70.875 g'' cheese eaten by a person per day, ''.0070875 kg''
*France's population found in Encarta Encyclopedia: ''58,609,285''
*That's approximately ''59 X 10<sup>6</sup> people''
:*So the rate of consumption is: ''59 X 10<sup>6</sup> people X .0070875 kg = 418 163 kg'' consumed per day.
*In the [[arithmetic series]] equation, I'd have to solve for n.
*<math>a_n = a_1 + (n - 1)d</math> would become <math>n= (an-a1)/d +1</math>.
*Then it would be <math>n= (1.18 X 10^{23} kg-418 163)/418 163 +1</math>
*So it would take France ''2.82 X 10<sup>17</sup>'' days to eat the moon.
What do you think?--[[User:JDitto|JDitto]] 07:04, 6 February 2007 (UTC)
== Planet Rotations ==
Why do all of the planets (and many other stellar objects) have ''somewhat'' parallel orbits around the sun? Why aren't there things orbiting the sun that are more perpendicular to the orbit of the planets? [[User:Imaninjapirate|Imaninjapirate]]<sup>[[User talk:Imaninjapirate|talk to me]]</sup> 00:55, 5 February 2007 (UTC)
:The prevailing theory ([[Planet#Formation]]) has the planets forming from a [[nebula]] condensing into a thin disk rotating around the proto Sun. There are things orbiting outside this narrow plane, but they're just not big things. [[User:Clarityfiend|Clarityfiend]] 01:06, 5 February 2007 (UTC)
:When matter starts to gather up, it tends to flatten in the shape of a disc, what we call [[protoplanetary disc]] (see article for a good explanation of why this happens.) This is how solar systems form. Most of the big objects in our solar systems were formed this way, that's why they all tend to have roughly the same orbital plane and move at the same direction. Smaller objects, however, are easily disturbed and have less-stable, irregular orbits. That's why smaller moons and asteroids have highly inclined orbits and all that. — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 01:19, 5 February 2007 (UTC)
:The flattening of a [[nebula]] into a [[protoplanetary disc]] is simply a case of the [[conservation of angular momentum]]. It is exactly the same reason why an ice skater spins faster when they pull their arms in closer to themselves. [[User:Carcharoth|Carcharoth]] 02:01, 5 February 2007 (UTC)
== Correlation of events...? ==
Where can I find the correlation between eating a big meal followed by a heart attack? [[User:71.100.10.48|71.100.10.48]] 02:41, 5 February 2007 (UTC)
: [http://www1.va.gov/resdev/news/press_releases/heart-attacks-103000.cfm This study] found that:
<blockquote>''Of the 158 patients who reported eating an unusually heavy meal during the 26 hours before their attack, 25 of them had the meal in the two hours right before the attack. Only 6 patients had their big meal in the corresponding two-hour period the previous day. By comparing the two time-slots-24 hours apart-the study controlled for the possibility that time of day, and not the meal itself, was the trigger. The remaining patients in the group of 158 had their heavy meal at various other times in the 26 hours before the heart attack, but no other time-slot emerged as significant.'' </blockquote>
:[[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 07:41, 5 February 2007 (UTC)
== Unknown disease ==
Anyone know of a disease nicknamed drop(s)? --[[User:The Dark Side|The Dark Side]] 02:52, 5 February 2007 (UTC)
: [[Dropsy]]? —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 02:55, 5 February 2007 (UTC)
== Reversed West and East on the Moon? ==
Hi - I read somewhere years ago that West and East are reversed on the Earth's Moon as a result of astronomers projecting our own West and East onto it - but now I can't find references to that idea anywhere - am I looking in the wrong places, or am I totally mistaken?
Thanks [[User:Adambrowne666|Adambrowne666]] 03:16, 5 February 2007 (UTC)
:Having a look at these two images: [http://photojournal.jpl.nasa.gov/catalog/PIA00120 Western Hemisphere] and [http://upload.wikimedia.org/wikipedia/en/7/73/Moon_PIA00302.jpg Moon surface]. It seems like they are not reversed. - [[User:Akamad|Akamad]] 05:20, 5 February 2007 (UTC)
::That's what I keep finding too - I've got such a strong impression of this notion, but can't find evidence of it - I wonder if it has always been the way it is now - is it possible early astronomers mapped it that way, and it has been switched since? [[User:Adambrowne666|Adambrowne666]] 10:49, 5 February 2007 (UTC)
:::It's an intersting point you make - it depends on how you define east and west - for instance does the sun always rise in the east? Is east defined by the rotation of the body? The earth and moon are separate bodies so it's difficult to say what is east on the moon??[[User:87.102.8.103|87.102.8.103]] 11:29, 5 February 2007 (UTC)
:It is either based on the rotation of the body, or the Earth as a reference. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 14:31, 5 February 2007 (UTC)
It might have something to do with the fact that astronomical telescopes invert the image. Since reverting the image will degrade it, astronomers have gotten used the inverted images, to the point that even their drawings are inverted. This would mean that "west" is on the right. Perhaps this is what the questioner has in mind. (But before you take this to the bank, this is remembered from when I was an astronomy buff, about 35 years ago. Maybe 'scopes have changed in the meantime). [[User:Bunthorne|Bunthorne]] 06:40, 6 February 2007 (UTC)
:Why would reverting the image degrade it? Surely a digitally stored image could be spatially inverted in a lossless fashion. I suppose you couldn't do it with an analogue form like a photograph, as you'd have to produce a new photograph from it, which would be a copy of a copy. [[User:Maelin|Maelin]] <small>([[User talk:Maelin|Talk]] | [[Special:Contributions/Maelin|Contribs]])</small> 04:09, 7 February 2007 (UTC)
::Sorry, I wasn't clear. While astronomers no longer look through modern scopes (they use CCDs instead), historically (before cameras) they would look through the eyepiece directly at the image. The only way to save the image to paper was to draw it, and they drew it as they saw it. Due to the optics of the scope, the image would appear upside-down. To have it appear right-side up would require extra lenses (or an erecting prism), thus degrading the image. So for many years, it was the convention that drawings, prints, etc. would be printed upside-down, just as it would appear in the telescope.[[User:Bunthorne|Bunthorne]] 07:12, 9 February 2007 (UTC)
:::::Well, rather than inverting the image, though that's a clever thought, Bunthorne, I always assumed it was because if the astronomer is facing North as he/she looks up at the moon, then West is to the left, East is to the right, and perhaps for ease of reference, he/she then maps the West to the left side of the Moon, East to the right - so that when you're standingg on the Moon itself, you get a reversed East and West ... does that make sense? [[User:Adambrowne666|Adambrowne666]] 21:36, 7 February 2007 (UTC)
::::::Yes I get that.. Though I've haven't yet found an example of a moon chart being labelled "east/west" - maybe astronomers have understood this two and avioded using east and west because of the potential for confusion? What they do use to describe degrees around the moon I have no idea - and the article [[moon]] doesn't seem to have the answer.[[User:83.100.250.165|83.100.250.165]] 21:41, 7 February 2007 (UTC)
<s>If you look at this image {Image:Moon map grid showing artificial objects on moon.PNG] and compare it with the list here [[List of artificial objects on the Moon]] you'll see that west on the moon is relative to the moon - not earth - so west goes right.. not left like on our earth maps...[[User:83.100.250.165|83.100.250.165]] 21:48, 7 February 2007 (UTC)
</s>Wrong way round - I'm asking at [[Wikipedia:Reference_desk/Science#moon east]]
:See [[Selenographic coordinates]]. --[[User:Heron|Heron]] 21:35, 9 February 2007 (UTC)
== only eating vitamins ==
What would happen if I stop eating conventional food and only eat vitamins? Would I die? What if I also eat sugar? Thank you. Renaud Miclette Lamarche
:From [[nutrition]]: "There are six main classes of nutrients that the body needs: carbohydrates, proteins, fats, vitamins, minerals, and water. It is important to consume these six nutrients on a daily basis to build and maintain healthy bodily function." If you take vitamins, that'd cover vitamins.
:And from [[Sugar#Health_concerns]], "The panel <nowiki>[at WHO]</nowiki> stated that the total of free sugars (all monosaccharides and disaccharides added to foods by manufacturers, cooks or consumers, plus sugars naturally present in honey, syrups and fruit juices) should not account for more than 10% of the energy-intake of a healthy diet, while carbohydrates in total should represent between 55% and 75% of the energy-intake."
:So the short answer is, no. --[[User:Wirbelwind|Wirbelwind<small>ヴィルヴェルヴィント</small>]] ([[User_talk:Wirbelwind|talk]]) 04:02, 5 February 2007 (UTC)
::YOu need some [[dietary fiber]] too. --[[User:Shantavira|Shantavira]] 08:15, 5 February 2007 (UTC)
:Vitamins are part of the group called [[micronutrients]] (along with minerals), which are needed in doses of milligrams or micrograms. Vitamins are needed for the body to be able to do properly some of its functions. [[Macronutrients]], that is lipids, carbohydrates and proteins are the bulk of our needs (doses in the order of magnitude of grams), and they provide energy. If you only ate vitamins you would be lacking almost all the daily energy intake and would become weaker and weaker in a very short time span (maybe less than 3 weeks) and with die of hunger. --[[User:Taraborn|Taraborn]] 10:10, 5 February 2007 (UTC)
You don't actually need polysaccharides, fat or protein for energy, but proteins are useful for other things instead
== mitosis and meiosis ==
do you have any draws of meiosis and mitosis?
:[[Meiosis]] and [[Mitosis]]? [[User:Splintercellguy|Splintercellguy]] 03:43, 5 February 2007 (UTC)
== Gummy Bear Rocket ==
I’m having a contest with my buddies to see who can make a device that can fling/shoot/launch a gummy bear the farthest, anything goes. I seem to remember a demonstration that rocketed a bear after it (the bear) was heated. Ring any bells?
Thanks --[[User:Willworkforicecream|Willworkforicecream]] 04:55, 5 February 2007 (UTC)
:You might want to see our article on [[Sabot]]s. With such a device (and perhaps a [[railgun]]), I'd imagine you could impart nearly unlimited velocity to your Gummy (former) bear.
:[[User:Atlant|Atlant]] 12:48, 5 February 2007 (UTC)
I would think that in order to have a contest, the bear would have to be a projectile in its natural state, and impact with full gumminess. Otherwise, you could just pour a melted gummy into a hollow-nose bullet, and fire away! --[[User:Zeizmic|Zeizmic]] 13:12, 5 February 2007 (UTC)
:If anything really goes, how about sending the gummy bear by [[air mail]] to someone living on [[antipodes|the other side of the earth]]? It will have flown most of the way. Or figure out some other way to get the gummy bear on an airplane.
:To beat even that, you'll need a friend who works at [[NASA]] and owes you a big favor. Unfortunately, you missed your [[New Horizons|best chance]] by just over a year. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 13:09, 5 February 2007 (UTC)
Today they told me that "anything goes" means anything mechanical goes, so chemical, magnetic, etc. isn't allowed any more. Wusses, they were just scared of my coilgun idea. --[[User:Willworkforicecream|Willworkforicecream]] 19:06, 5 February 2007 (UTC)
You could build your own scale model of an aeroplane, and stick it to that
::Well, if you aren't allowed any chemical or magnetic you can't use anything with an engine, I'm thinking: "What did people use to fling things far before engines and explosives and stuff?". I'd be investigating [[trebuchet]] and [[catapault]]. [[User:Vespine|Vespine]] 21:50, 5 February 2007 (UTC)
You could try a [[stomp rocket]] or a [[water rocket]]. [[User:Theresa knott|Theresa Knott]] | [[User talk:Theresa knott|Taste the Korn]] 21:57, 5 February 2007 (UTC)
: Hmm a red link! See [http://www.sciencetoymaker.org/airRocket/index.html here] [[User:Theresa knott|Theresa Knott]] | [[User talk:Theresa knott|Taste the Korn]] 21:59, 5 February 2007 (UTC)
::And I've turned it blue. If anyone wants to help edit our brand new stomp rocket article please feel free. [[User:Theresa knott|Theresa Knott]] | [[User talk:Theresa knott|Taste the Korn]] 22:33, 5 February 2007 (UTC)
Thanks for the ideas. I think that I'll go with a trebuchet because they're awesome. I'll blow everyone out of the water by putting the bear inside of a bouncy ball that will bounce and roll to gain extra distance. --[[User:Willworkforicecream|Willworkforicecream]] 18:51, 6 February 2007 (UTC)
:That might be an excellent idea, if the terrain downrange is such that the ball will bounce nicely on it. If the terrain was, say, loose sand, I'd suggest a (mostly) solid iron/steel ball instead: maximizing the [[density]] of the projectile minimizes the effects of [[atmospheric drag]]. In any case, you may want to experiment with balls of various sizes and materials. Denser is still better, but [[elasticity (physics)|elasticity]] will count a lot too if you go for the bounce. The optimal size of the ball (for a given material) will depend on how powerful your launcher is: too big and the initial velocity will be low, too small and you'll lose speed to drag; a [[back-of-the-envelope]] calculation of the optimal mass would be a nice physics exercise, but in practice an [[empirical]] approach will probably work just as well if not better. I'd expect a fairly large [[superball]] might do well, if you can get the gummy bear inside it without ruining its bounce. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 20:13, 6 February 2007 (UTC)
== a weed pest called Wolsia or Wollsia ==
This pest is growing in our dam and we cannot find a way to get rid of it - the plant has been identified by the Department of Natural resourses Queensland but they have no knowledge of how to kill it Gwen Kelly
:I can't find any info on those two names, I don't think you have spelt it right. If you can't find the correct name, would you be able to upload a photo here? Thanks. --[[User:LiquidGhoul|liquidGhoul]] 12:46, 5 February 2007 (UTC)
[[woollsia]] in [[Ericaceae]] ?[[User:87.102.8.103|87.102.8.103]] 18:02, 5 February 2007 (UTC)
:Most pest plants aren't easy to kill - that's why they become pests - you need to find out how it can regenerate - for instance some plants can survive fire / chopping down - because they have a [[rhizome]] - the plant regenerates from the [[rhizome]] - is this is the case one way to proceed is to keep chopping it down - eventually the store of energy in the rhizome will be used up and the plant die.
:You could try using a strong weedkiller - killing everything - don't forget to salt the ground as well.
:An alternative is to add an even more invasive species that out grows it.
:Or if you are lucky a pest that kills the plant can be found.
:It's difficult to beat nature though.[[User:87.102.8.103|87.102.8.103]] 18:15, 5 February 2007 (UTC)
::You're evil. – [[User:b_jonas|b_jonas]] 20:45, 6 February 2007 (UTC)
== Han and Hong classification of inverted nipples ==
This classification is used by plastic surgeons to classify the three main types of inverted nipples. The Han and Hong classification is often cited in journals. I would like to know when this classification first came into effect, the first time it was published and where and also who owns the copyright to this classification. Thank you. Dharani.
:Look at the last journal article in which you saw it cited-- it likely contains the reference that answers your question. [[User:Alteripse|alteripse]] 14:05, 5 February 2007 (UTC)
== Hyperbolic cooling ==
Do the huge "hyperbolic cooling towers" seen in power stations actually utilize a section from the perfect shape of hyperboloid? If so, how close to the shape is it? And how does this system improve water cooling efficency?[[User:Wbchilds|Wbchilds]] 10:15, 5 February 2007 (UTC)
:I can't answer your first two questions. But the reason for the shape is one of structural integrity see [[Cooling_towers#Cooling_Towers_of_Nuclear_Reactors]] The shape is chosen for it's stabilty not to improve cooling efficiency. (Not sure if that was your question)[[User:87.102.8.103|87.102.8.103]] 11:36, 5 February 2007 (UTC)
== Projectile Motion ==
I'm currently doing a prac write up for year 12 Physics. At the moment I've hit some what of a road block. I'll try to describe the problem. A projectile is fired from a table (same height as the table) at a 45° angle, the projectile lands on the ground 2.54m away. The table is 0.75m high. The speed of the projectile is unknown, the time of flight is unknown. Is it possible to work out how far away from the origin the projectile is when it comes in line with the table. Heres a diagram I drew in MS Paint to help illustrate the problem:
[[Image:Projectile_motion_question_diagram.JPG|center]]
The green question marks indicate the value I would like to know.
Oh yeah, I almost forgot, Ignore air resistance.
P.S. If anyone works this out could they please tell me how because I would also like to do this with my measurements of other angles/distances.
P.P.S. This isn't really counted as "answering my homework" because we aren't required to put this info in our prac report, I simply want to enhance it.
:Yes you can. First, if you were given the initial velocity, angle (which is known), and the time after firing, can you calculate where (x,y position) the projectile is? If so, you have a known (x,y) position of the projectile at some point (the position where it hits the floor, relative the the firing position). From that you should be able to solve for the initial velocity and time after firing (2 equations with 2 unknowns). With the initial velocity and angle, you should easily be able to solve your problem. --[[User:Spoon!|Spoon!]] 12:09, 5 February 2007 (UTC)
:(edit conflict) Well, ignoring air resistance, the trajectory is a [[parabola]], which, in general, is described by the function <math>y(x) = ax^2 + bx + c</math>, with the [[Derivative#Notations for differentiation|first derivative]] <math>y'(x) = 2ax + b</math>. Setting the [[Origin (mathematics)|origin]] to the starting point on the table, we have <math>c = 0</math>, and the starting angle tells us that <math>y'(0) = b = 1</math>. The remaining condition is that <math>y(2.54) = a(2.54)^2 + 2.54 = -0.75</math>, which can be rearranged to give <math>a = -(0.75 + 2.54)/(2.54)^2 = -0.51</math> (approximately). Solving for <math>y(x) = -0.51x^2 + 1x = 0</math> [[Quadratic equation#Quadratic formula|the usual way]], we get <math>x = 1/0.51 = 1.96</math> (again approximately). Depending on how pedantic your teacher is about [[Significance arithmetic|significant figures]], you may need to round that up to <math>2.0</math> meters (since the table height was technically given only to two significant digits), though in practice I'd consider the three-digit figure a more useful answer. Ps. If you do use these answers in your report, remember to be nice and credit the reference desk. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 12:36, 5 February 2007 (UTC)
== science in transportation ==
information of what science contribute in transportation.
{{unsigned2|14:37, 5 February 2007|210.186.3.142}}
:I guess you mean "information from which sciences contributes to transportation (technology)." - if so the answer includes [[engineering]] primarily, [[computer science]] in modern computer controlled systems, [[mathematics]] - various models not related to engineering eg queueing theory, [[chemical engineering]] and [[metallurgy]] contribute to materials used in construction of transportaton devices, [[social science]]s may also help in the design of public transportation systems, [[geography]] and [[geology]] relate to the way the transport network is built, [[meteorology]] is important easpecially in sea and air travel, in fact most of the common practical sciences contribute in some way.[[User:87.102.8.103|87.102.8.103]] 15:29, 5 February 2007 (UTC)
== To measure distances on earth ==
I woud like to know how i can measure shortest way from a place to an other, for exsamble from boston to london.Any
solution for this.
hp
:If you know the [[latitude]] and [[longitude]] of the two places, and you assume the earth is spherical it's quite simple.
:First calculate the angle between the two places, using the latitude and longitude (relative to the centre of the earth. If you don't know how to do this please ask about it.
:Then multiply the angle(in degrees) by 2πR/360 - ie Anglex2πR/360 this is the length of an [[arc(geometry)]] which subtends an angle of A - that is the distance 'as the crow flys' - R is the radius of the [[earth]].
:If you want the absolutely shortest distance from A to B (ie though the earth's crust in a straight line the distance is 2Rsin(πA/360) [[User:87.102.8.103|87.102.8.103]] 16:30, 5 February 2007 (UTC)
See the articles [[Great circle]] and [[Great-circle distance]]. The second article describes a method which uses a [[sphere]] to approximate the shape of the earth, and the article claims a maximum error of about 0.5%. The problem of finding a [[geodesic]] on an oblate [[spheroid]] is much more complex and cannot by solved analytically.
For calculating the shortest distance between two points along a straight line running beneath the surface, convert the [[latitude]] and [[longitude]] of the two points to earth centered, earth fixed coordinates:[http://www.colorado.edu/geography/gcraft/notes/datum/gif/llhxyz.gif].—[[User:EricR|eric]] 16:59, 5 February 2007 (UTC)
isn't the cross section of the earth elliptical, meaning the difference from the equator streight up is proportional to the distance from a line between the poles outward
== Is denatured alcohol 100% volatile as a solvent? ==
If I were to extract some essential oils from lavendar using denatured alcohol, would it completely evaporate (like acetone or high grade ethanol)?
:typically no. If it's surgical spirit no - it leaves an oil behind. If it's purple 'meths' no it leaves a purple residue.
:You should be able to get denatured alcohol that does not leave a residue (I assume to avoid having to pay tax) if you seek it out specifically - that could be ethanol with only methanol in. Find a supplier (chemical or similar - and tell them what you want)
:Alternatively you could distil some other denatured alcohol to get a residue free liquid (obviously this is a potential hazard and may even require a license to do..) and the distillate may carry over some impurities.
:Or it's possible to use alternatives such as propanol.[[User:87.102.8.103|87.102.8.103]] 17:22, 5 February 2007 (UTC)
== Pissing too often ==
i recently switched from sitting down when i piss to standing up. all of a sudden, it seems like i need to take a leak too often. could it be because sitting down empties my bladder better or is this a sign i could have a serious male medical condition.. i dono prostate colorectal something like that? do i need to see the doctor? i dono why im asking all these questions.. shouldn't i just switch back to sitting and see if the problems stops?
:There are lots of different causes of needing to piss more often - including mild infections, over injestion of diuretics (eg coffee), psychological reasons and more serious problems and diseases. As I/We can't see you and check your general health or ask about what other factors may be an issue it's really impossible to give you an good answer.
If it's a problem eg you can control your bladder (wet yourself), or are pissing many times more often than you should you should see a doctor - definately.
However if the difference in the amount of pissing you are doing is trivial - Could it be because it's easier to piss standing up that's why you go more often?
I'd recommend you go and see a doctor - and ask them about it. They usually give you a look over anyway so you should get some feedback on your general health as well as getting an answer to this problem.[[User:87.102.8.103|87.102.8.103]] 19:44, 5 February 2007 (UTC)
::Hmm Could be diabetes. Go to see a doctor soon! <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:88.109.41.162|88.109.41.162]] ([[User talk:88.109.41.162|talk]] • [[Special:Contributions/88.109.41.162|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
== Dog breeds -- Help! ==
Why are chihuahua, poodle, pit bull, labrador retriever, and alaskan husky considered different breeds of the same species, while lions, mountain lions, tigers, jaguars and leopards considered diffirent species of cat? they seem equally unsimilar to me. our [[Species]] article says something about a species being a group of animal that can succesfully reproduce and produce fertile offspring. is it even possible for chihuahua and the large domestic dogs reproduce togeher!? if so, is that what makes them one species? and thers so many species of jackal, coyote, and wolf. why arent they lumped together? they cant interbreed?
members of a specis also have to have physiological, morphological, biochemical and behavioral similarities, but this is mostly just for taxonomy which hardly anyone uses now
: This [[Wikipedia:Reference_desk/Archives/Science/2007_January_26_%26_27#Breed_and_race....3F|discussion]] cover some aspects of dog breeding. However, the major difference is that the dogs you list are [[domestication|domesticated]], while the felines are not. And thus the [[generation]] time since the [[last common ancestor]] of the dogs is much, much shorter than the last common ancestor of the cats. The cats have become [[speciation|speciated]], the dogs have not. [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 20:00, 5 February 2007 (UTC)
::All breeds of dogs -- even a [[Chihuahua (dog) |chihuahua]] and a [[great dane]] -- can reproduce and create fertile "hybrids". The fertility of the feline species in question is a bit [[Liger#Fertility | more complicated]], however. Also note that, for example while a coyote and a wolf can interbreed, their offspring tend to be less fit than a pure-bred and often die in the wild, whereas an interbred dog has about equal survival-ship ([[Fitness (biology) |i.e. fitness]]) as a pure-bred. Check out [[speciation]] and [[Hybrid |hybridization]]. --[[User:Cody.pope|Cody.Pope]] 07:50, 6 February 2007 (UTC)
::: Do you have data for the assertion "an interbred dog has about equal survival-ship ([[Fitness (biology) |i.e. fitness]]) as a pure-bred"? The common held belief is that a [[mongrel]] has a greater fitness than a pure-bred, due to a reduction in [[inbreeding depression]]. While I'm sure that isn't the case all the time, I would propose that on average, first generation outbreds would be fitter than first generation inbreds, due to a reduction in homozygosity. [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 07:45, 7 February 2007 (UTC)
On that note, have a chihuahua and a great dane ever mated and produced offspring? I'd imagine the mother would have to be a great dane, as great dane puppies would probably be too big for a mother chihuahua... but then how would a male chihuahua... erm... "reach" the female great dane? And what would the offspring look like? --[[User:Candy-Panda|Candy-Panda]] 09:27, 6 February 2007 (UTC)
:I don't know if they have done it, but usually when breeders try to mate two creatures of very different sizes, they use [[artificial insemination]]. Certainly, new cat and dog breeds are sometimes started by crossing existing breeds. [[User:Skittle|Skittle]] 00:41, 7 February 2007 (UTC)
:While I don't personally know of any actual examples of a chihuahua × great dane, if asked to bet I'd put my money on it having happened several times quite naturally. Where there's a will there's a way, after all, and dogs in heat certainly have the will. For what it's worth, I did once meet a dog that was reportedly the offspring of a (male) [[papillon (dog)|papillon]] and a (female) [[siberian husky]]. He seemed like a quite normal medium-sized dog, with somewhat fluffy fur, a distinctive bark and a strong temperament, but nothing that would've really struck me as particularly out of the ordinary. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 14:46, 9 February 2007 (UTC)
== Using digital sound recorder as decibel noise meter? ==
I've just bough a digital sound recorder - a Tevion Digital Voice Recorder ET-880 to be exact. It can communicate with a computer via USB. It can record in "ACPCN", "ACTPC", and possibly "WMA" sound formats. I'm wondering if I could use it as a decibel noise meter by measuring the average sound intensity when the recorded file is transferred to the computer?
{{unsigned2|22:16, 5 February 2007|62.253.44.193}}
:(This answer is aimed at digital audio recorders in general, not this specific one which I only find very little information about.) I don't see how you could end up translating this into db. For one thing, whatever mic is built into the recorder is going to have certain [[Audio level compression|compression]] characteristics. Also, the level of the sound in your digital recording is going to depend on where your level was set when you recorded, assuming the recorder lets you do this. Long story short- I think in order to measure [[sound pressure level]]s, you need a device specifically intended for this. [[User:Friday|Friday]] [[User talk:Friday|(talk)]] 22:34, 5 February 2007 (UTC)
::You you do, do you? And what do you knoew about anything/ <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:88.109.41.162|88.109.41.162]] ([[User talk:88.109.41.162|talk]] • [[Special:Contributions/88.109.41.162|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
::All the same I have known professional noise pollution specialists use a calibrated mic (don't know how calibrated, don't know brand) and a high quality portable recorder (Nagra back in the analog recording days) to record ambient sound on site before a plant is built, then run it through an analyzer back at the lab to determine the dB of noise pre- and post- plant operation. If they had just stared at a meter dial and written down the dB of ambient noise before the plant was built, they could have waited until a truck went by. If someone doubts the high pre-plant noise level, they can haul out the tape and show that it was the pig farm, birds, or bullfrogs. In general mics do not compress sound in the usual sense, but they have a certain gain, like -50dB and a certain frequency curve and directionality which has to be taken into account. The trick would be having a calibrated mic with a calibrated preamp, so that a certain sound pressure level produced a certain level n the recording, then to filter the sound per the applicable [[Weighting filter]] to get dbA, for instance. See [[Weighting filter]] and [[decibel]] for more info and more links. If the desire were to use the system for litigation or environmental health legal applications, an ad-hoc system would be subject to criticism, but if it were to satisfy curiosity, you might be able to conjure up a system. [[User:Edison|Edison]] 00:47, 6 February 2007 (UTC)
== Quality of radio reception dependent on where I stand ==
When I have the radio on in my room, sometimes the reception is good when I stand in a certain spot (even in a certain position) and turns crappy as soon as I move from there. How does this happen and is there a (easy) way to improve the reception?
Thanks [[User:Lukas.S|Lukas]] 22:32, 5 February 2007 (UTC)
:Yeah dont stand where the sound is crappy <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:88.109.41.162|88.109.41.162]] ([[User talk:88.109.41.162|talk]] • [[Special:Contributions/88.109.41.162|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
::I think that the reason you see the effect is generally capacitance between you and the antenna. To improve reception, either stand where reception is good the whole time, or try moving the antenna higher up. [[user:anonymous6494|anonymous6494]] 23:33, 5 February 2007 (UTC)
:(Edit conflict) At about 3 metres, the [[wavelength]]s of broadcast FM signals are ''roughly'' the same size as you, so you can interact pretty strongly with those FM waves, diverting them around you or reflecting them. This can produce [[Interference|constructive or destructive interference]] at your radio's antenna. You may be able to reduce some of this by changing the position of the antenna (remembering that many table radios use their power cord as their antenna). In particular, if the antenna is oriented vertically (as you usually are when walking around), try orienting it horizontally.
:[[User:Atlant|Atlant]] 23:39, 5 February 2007 (UTC)
== weather ==
What type of weather does low air pressure usually indicate?[[User:24.34.194.200|24.34.194.200]] 22:47, 5 February 2007 (UTC)
:[[Storm]]y weather <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:88.109.41.162|88.109.41.162]] ([[User talk:88.109.41.162|talk]] • [[Special:Contributions/88.109.41.162|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
:See also [[Cyclone]]. – [[User:b_jonas|b_jonas]] 20:33, 6 February 2007 (UTC)
== more for the poison question above ==
ok guys first i wanna say thanks so much for helping me understand the effects of the poisons and everything. its really grea and secondly i wanna say thanks for not sugar coating the effects!! now ok here we go as for cyinade posion. if you were to keep the heart beating and the lungs working (via CPR or another method) would it be possable to survive a normal Leathal dose of cyinade once it goes through the body (since it does so at a fast rate) ?? or will the cell damage the cyinade causes be too great to survive?? thanks again [[User:Maverick423|Maverick423]] 22:55, 5 February 2007 (UTC)
:You asked a similar question recently, and the first reply had a few errors in it, I would encourage you to scroll up and see the corrections if you haven't already done so.
So as stated above, ATP is the fuel with which the cell carries out many functions. Cyanide causes death by disabling ATP synthesis, and cells and by extension the entire human organism dies as a result. ATP acts on the enzyme ''cytochrome C oxidase'' by binding to it and preventing it from performing its normal duties. Cyanide also denatures the cytochrome, preventing further use. There are drugs which help avoid interaction between the cyanide and enzyme, but you are asking whether someone could be kept alive through CPR until the cyanide has the chance to exit the cells. The answer is, unfortunately, no. [[Cytochrome c oxidase]] takes four electrons (originally from [[NADH]] produced in the [[TCA]]) and adds them to molecular oxygen, creating (with dissolved protons, or hydrogen ions) water. This powers the Cytochrome c oxidase to push four hydrogen ions into a space in which they can power the transmembrane protein that creates ATP from [[ADP]]. The entire purpose of oxygen, despite the fact that it propagates toxic molecules and is itself reactive to vital cellular structures, is to accept these electrons from cytochrome c, as mediated by the oxidase. Oxygen, that vital substance, is just an electron sink. Without cytochrome c oxidase, oxygen is useless to the human body. Since CPR is little more than an artificial method to keep the body perfused with oxygenated blood, you can see why even perfect oxygenation of cells during cyanide poisoning is useless. Also note that, since the cyanide destroys the enzyme discussed, the body would have to make new cytochrome to replace it, which requires ATP, which is not available. All medicine can do in the case of cyanide poison is prevent it from interacting with cytochrome in the first place (and other important molecules) by introducing an agent which the cyanide prefers to bind with. See [[methemoglobin]]. <sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .1em .1em .9em .1em;">tucker</font>]]</sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .35em .1em .35em .1em;">/</font>]]<sub>[[User:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .9em .1em .1em .1em;">rekcut</font>]]</sub> 02:12, 6 February 2007 (UTC)
Thanks much tuckerekcut you have been very helpful in my quest for intellect. [[User:Maverick423|Maverick423]] 14:20, 6 February 2007 (UTC)
== dental hygienist/therapist ==
Hi, I am applying for a job as a dental nurse in Scotland, hoping to progress to a hygienist/therapist. What kind of uniform would I be wearing typically, and would I use a stethoscope etc in the latter jobs?
Yours,
Alan
: Hello Alan. Having been to a few dentists in Scotland, my personal experience is that the nurses and hygienists tend to wear tunics like [http://www.workinstyle.com/?stockGroup+2959454_25818+4+14+78 this chap]. I have never seen a [[stethoscope]] being used in a dental office. [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 01:05, 6 February 2007 (UTC)
::....Nor by a hygienist or therapist, though there are many different kinds of therapist, and some might have a use for a stethoscope. [[Stethoscope]] will explain what it's for.--[[User:Shantavira|Shantavira]] 08:40, 6 February 2007 (UTC)
=February 5=
== The 'pill' equals weight gain? ==
A couple of days ago I was reading the local newpaper's science page. One of the columns was a Q&A about science topics. The question was wether or not the 'Pill' really caused weight gain (or how). The answer was that, while older types of the pill did cause weight gain, newer ones had a different balance of hormones that did not cause much weight gain. The Doctor went on to say that the reason so much weight gain was from a natural increase of weight around the typically time the pill started to be used (IE 16 years or such)
Is this true? --[[User:Honeymane|<font color="red" face="Old English Text MT, Papyrus">Honeymane</font>]]<sub>[[User_talk:Honeymane|<font face="Klingon, QuigleyWiggly">Heghlu meH QaQ jajvam</font>]]</sub> 00:16, 6 February 2007 (UTC)
: The authors of an academic study into that very question (Gallo M. F., Lopez L. M., Grimes D. A., Schulz K. F. & Helmerhorst F. M. Cochrane Database Systematic Rev., doi: 10.1002/14651858.CD003987.pub2. (2006)) conclude that:
<blockquote>'' 'cause and effect' is merely anecdotal, and that patterns of weight gain among new pill users are no different to those seen in the population at large. The most logical explanation is that all of us, men and women, gain weight with age. The average American, for example, gains about one pound (0.45 kilograms) every year, but most people seek out something to blame for this other than their personal behaviour.'' [http://www.nature.com/news/2006/060123/full/060123-4.html#B1] </blockquote>
:[[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 01:22, 6 February 2007 (UTC)
::Should the article be changed to reflect this?--[[User:Honeymane|<font color="red" face="Old English Text MT, Papyrus">Honeymane</font>]]<sub>[[User_talk:Honeymane|<font face="Klingon, QuigleyWiggly">Heghlu meH QaQ jajvam</font>]]</sub> 23:10, 6 February 2007 (UTC)
::: Why not '''[[WP:BOLD|be bold]]'''? [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 07:35, 7 February 2007 (UTC)
== air in potato chip bags ==
why is there so much air in potato chip bags? Is anything else a factor for their freshness?
:It's in part to discourage breakage. [[User:Anchoress|Anchoress]] 00:46, 6 February 2007 (UTC)
::Air would actually make the chips spoil faster because of the oxygen; I believe [[nitrogen]] gas is used instead of air. (Potato chip makers in Korea state that they use nitrogen.) --'''[[User:Kjoonlee|Kjoon]]'''[[User talk:Kjoonlee|lee]] 00:55, 6 February 2007 (UTC)
:::Was that a response to my comment? Because my point was that when the bag is inflated (with whatever gas) to maximum size the chips are less likely to break due to compression or impact during the journey from manufacture to sale. [[User:Anchoress|Anchoress]] 17:54, 6 February 2007 (UTC)
::::I'm sorry, I meant my reply to point out that the original question had a weak point. I agree wholeheartedly with your comments. :) --'''[[User:Kjoonlee|Kjoon]]'''[[User talk:Kjoonlee|lee]] 18:36, 6 February 2007 (UTC)
I always thought air in the bag was just to make it look more full then it is so that the person buying it wont feel as bad when they pay $3 for 10 ounces of chips. [[User:Maverick423|Maverick423]] 14:37, 6 February 2007 (UTC)
:Except it isn't air, as mentioned above; Korean manufacturers state it very clearly: "Filled with nitrogen to protect contents." --'''[[User:Kjoonlee|Kjoon]]'''[[User talk:Kjoonlee|lee]] 15:09, 6 February 2007 (UTC)
::Ooh, the [[potato chip]] article confirms the use of nitrogen. Isn't Wikipedia wonderful? :) --'''[[User:Kjoonlee|Kjoon]]'''[[User talk:Kjoonlee|lee]] 15:15, 6 February 2007 (UTC)
Yes very intresting info well i guess you learn something new everyday =) [[User:Maverick423|Maverick423]] 16:30, 6 February 2007 (UTC)
== Point to point Rocket travel: How is it possible to get from any point on Earth to another in just 45 minutes? ==
Hello Volunteers:
I've tried to research Point to point Rocket travel: How is it possible to get from any point on Earth to another in just 45 minutes?
All I'm able to locate is information about rocket/space travel and how point-to-point rocket travel can be done in 45 minutes etc...but I haven't been able to locate any info on how it works...why does it take only 45 minutes... ?
thanks in advance for all the answers
[[User:Shaum76|Shaum76]] 01:09, 6 February 2007 (UTC)
:An object in a [[low Earth orbit]] (LEO) takes about 90 minutes to complete one full orbit of the Earth. Now, think of a point-to-point rocket journey as a rocket in a slightly flattened (elliptical) orbit that intersects the surface of the earth at your departure point and at your destination. Neglecting the (relatively short) periods of acceleration at takeoff and landing, the furthest point on Earth from you will be no more than half the circumference of the Earth away (half an orbit): 45 minutes.
:It is in principle possible to get from point to point even faster, but only at ruinous cost of fuel. A faster trip would essentially require you to burn fuel the whole way, instead of coasting for most of the trip. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 02:03, 6 February 2007 (UTC)
You can do better than 45 minutes (actually about 42) using a [[Gravity train]]. [[User:Bunthorne|Bunthorne]] 06:56, 6 February 2007 (UTC)
== Light: Vector or Scalar? ==
Me and a few of my friends at school have been debating whether or not light is a vector or scalar quantity. Is it the SPEED of light, or is it the VELOCITY of light? What is the convention used and how does light actually travel, and what are the reasons for this?[[User:67.70.30.223|67.70.30.223]] 02:01, 6 February 2007 (UTC)Adam Reid
:Light is neither; its speed is a scalar and its velocity is a vector. Scalars and vectors are not mutually exclusive. I don't understand what you mean by how light actually travels. [[User:Clarityfiend|Clarityfiend]] 02:49, 6 February 2007 (UTC)
::Light is vector. It has energy and a direction. Interactions with other particles with vector properties preserves the vector/vector rules, not vector/scalar rules. Light has momentum which is the inherent vector quantity. [[User:Tbeatty|Tbeatty]] 03:22, 6 February 2007 (UTC)
:::I don't think you can classify light as vector just because it has energy and momentum. For example, you can not say that a moving car is a vector. Scalars and Vectors are physical quantities and not objects. But as Clarityfiend mentioned, if you say ''velocity'' of light, then you need to mention the direction too, because velocity is a vector. You can say 'the speed of light is so and so' but if you say 'the velocity of light', then you should specify 'in the eastern direction' or something like that. -- [[User:wikicheng|Wiki'''''Cheng''''']] | [[User talk:wikicheng|Talk]] 13:15, 6 February 2007 (UTC)
:If you're thinking of light as an object, the above answers are correct: its speed is a scalar, but it's velocity is a vector. To muddy the waters, and not at all because I think this is what you were debating about, in [[electrodynamics]], light is described by the [[electromagnetic four-potential]]; in [[quantum electrodynamics]] (the [[quantum mechanics|quantum-mechanical]] version), individual [[photon]]s are [[quanta|little localized packets]] of this field. From this perspective, light ''is'' a vector after all, and photons are one example of a [[vector boson]]. (Any particle with [[spin (physics)|spin]] of 1 unit, like the photon, is a vector; those with a spin of 0 units would be [[scalar field|scalars]].) -- [[User:SCZenz|SCZenz]] 13:38, 6 February 2007 (UTC)
== Too much tea? ==
I drink a lot of tea - at least 3 and sometimes up to 6 or 7 cups a day of [[green tea]], [[white tea]] and regular [[black tea]]. I drink soy milk with black tea but I don't use sugar. I also consume other antioxidant-rich things like red wine and cranberry juice on occasion. Are there any possible negative side effects of so much tea consumption? --[[User:The Famous Movie Director|Grace]] 02:39, 6 February 2007 (UTC)
Yes you can have too much [[caffein]] and get the jitters or [[insomnia]]. Also your teeth may be discoloured by too much tea.
Is soy milk with black tea called white tea though?
[[User:Graeme Bartlett|GB]] 05:52, 6 February 2007 (UTC)
:By the way, you know consuming too much [[antioxidant]]s can be unhealthy, mostly happens with vegetarians though, but you seem like you get a lot. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 07:06, 6 February 2007 (UTC)
::Overconsumption of too much of one particular antioxidant chemical has been linked to health problems, but tea contains so many I don't think it's something to be worried about. (I don't think anyone has ever been diagnosed with antioxidant overconsumption from food, vegetarian or not). There are many folks who drink many cups of antioxidant-rich green tea a day with only positive effects that we know of. Also, white tea is a different variety of tea, similar to green tea. [[User:Frankg|Frankg]] 15:28, 6 February 2007 (UTC)
:You might be interested in this article: [http://www.cbc.ca/health/story/2007/01/09/tea-milk.html Heart study pours cold water on adding milk to tea.] [[User:Anchoress|Anchoress]] 15:33, 6 February 2007 (UTC)
::Thanks for your answers everyone...Mac Davis, what's wrong with consuming too much (too many?) antioxidants? In the article it mentions that they may prevent your body from using other important nutrients, would taking vitamins offset this? --[[User:The Famous Movie Director|Grace]] 23:49, 7 February 2007 (UTC)
== Dirty Glass Recycling ==
Some people put dirty jars in glass recycling bins. Are these jars just fed into a the glass melting machine all dirty or what? What about the label? What about the glue residue that attaches the label to the glass? --[[User:Seans Potato Business|Seans]] '''[[User talk:Seans Potato Business|Potato Business]]''' 04:28, 6 February 2007 (UTC)
:When I talked to the local recyclers about this they said there was no need to wash out leftovers or remove labels. The glass material is sorted out and the company washes it anyway, and then melts it down. However they don't want light globes, window glass, pyrex or any other weird kinds of glass that muck up the mix. You may wish to wash out the remains to cut down on odor as it decomposes though. The same story applied to metal cans for recycling. [[User:Graeme Bartlett|GB]] 05:50, 6 February 2007 (UTC)
::I'd agree with GB. Glass melts at such a high temperature that most things would just burn off. Any other oddities left behind (metals etc.) could just be separated out by density. --[[User:Cody.pope|Cody.Pope]] 07:36, 6 February 2007 (UTC)
:::Yes and no. Plenty of organic stuff, I'm sure, burns off without a trace. But glass is a pretty weird substance, and even when molten it's still very, very viscous. Lots of metals and minerals can remain intermixed with it and do not by any means separate out by density. Trace amounts of various metals and minerals are routinely added to glass to give it desired colors or other properties. But those elements, if present in waste glass, can't be used to make a new batch of glass if those elements aren't desired in the new batch. That's why window glass is not welcome in the recycled glass stream. Also, I learned during a visit to a glass recycling plant that even one green bottle mixed in with several thousand clear ones can ruin a batch of clear glass. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 13:10, 6 February 2007 (UTC)
:::<small>[Footnote: I said that "even when molten glass is still still very, very viscous". Let's not hear anything about the [[Glass#Glass as a liquid|urban legend]] of its alleged viscosity at room temperature, 'kay? —[[User:Ummit|s]]]</small>
:::::A lot of recycled materials are not sold as "virgin" versions of the same substance, such as paper. Old milk cartons go to make park benches, not new milk cartons. I wonder if old recycled glass likewise gets downgraded to brown or green glass or non-seethrough glass products. It would seem silly to try to have perfect clear windoe or bottle gmass when one speck of adulterant would tint it. The glass gets smashed to bit, then a furnace burns away bits of paper or glue or spaghetti sauce, then I expect some of the other undesired substances float to the top as scum or slag and get skimmed off. I have always been doubtful of the need to run empty jam jars through the dishwasher or to scrub them in the sink, due to the water and fuel energy wasted. [[User:Edison|Edison]] 18:26, 6 February 2007 (UTC)
== Trees ==
what is Adenanthera pavonina,L.?
:It's red sandalwood, here's a page I found via google: http://www.tropilab.com/adenan-pav.html. By the way, in future, it's probably a lot quicker for you to search on google, or some other search engine for that matter. All the best. - [[User:Akamad|Akamad]] 05:04, 6 February 2007 (UTC)
== Torpedo away ==
According to [[U-Boat#World War II]], a magnetic torpedo worked by exploding underneath a ship, creating an air bubble that displaced the water supporting the weight of the ship; the unsupported hull then buckled. Is this true? [[User:Clarityfiend|Clarityfiend]] 04:39, 6 February 2007 (UTC)
:It does not sound like a true statement, as an exploding torpedo would increase the pressure, lifting the ship. The gas bubble should be able to support the ship due to its high pressure. Much of the damage would be due to the blast shock wave. [[User:Graeme Bartlett|GB]] 05:45, 6 February 2007 (UTC)
::My mistake. The article mentioned the air bubble, but the rest was my hallucination. [[User:Clarityfiend|Clarityfiend]] 06:42, 6 February 2007 (UTC)
Actually I've heard the exact same thing - twice - from ex-naval people - though not torpedos - more mines - the mine explodes - releasing a lot of gas - the gas expands becuase it is under pressure - creating a huge gas bubble under the target - and because gas doesn't have the buoyancy of water the ship sinks - that's the theory - just because I heard it from a good source doesn't mean it has to be true.[[User:87.102.37.127|87.102.37.127]] 06:55, 6 February 2007 (UTC)
:It's not accurate. Refrence [http://www.abc.net.au/science/k2/moments/s1448475.htm] for a complete description. [[User:Hipocrite|Hipocrite]] - [[User talk:Hipocrite|«<small>Talk</small>»]] 14:33, 6 February 2007 (UTC)
== Effect of radiation/nuclear bomb on U.S. currency tests ==
I heard from a reliable source that the U.S. had conducted tests concerning the effects of radiation/a nuclear bomb on United States currency. However after doing a little reaserch I was unable to find any information on any test or tests pertaining to this subject. If anyone knew any information concerning this (i.e. date, place, test name, results, ect.) please enlighten me.
[[User:Mattheyborne|Mattheyborne]] 04:53, 6 February 2007 (UTC)Matt
:If the currency (notes or coin) was near enough to the bomb, it would be destroyed (vaporised)--[[User:DarkFuture|DarkFuture]] 06:19, 6 February 2007 (UTC)
:Despite what Mattheyborne says: I have heard about different types of Nuclear Weapon which are designed to produce a huge amount of fallout without much actual explosive yeild. for example to kill the inhabitants of a city without actually causing much damage to infrastructure. the information about this type of bomb can be found [http://en.wikipedia.org/wiki/Atomic_bomb here]. Not sure if this helps, but i hope so. Ben
::You're talking about a [[neutron bomb]], although why the government would be overly concerned about the survivability of currency in the event of a nuclear war is beyond me. You'd think it would have more immediate worries. [[User:Clarityfiend|Clarityfiend]] 17:21, 6 February 2007 (UTC)
:::Governments generally assumed that nuclear warfare would not in fact end the world or their governments, but that it would be seriously disrupting. This is the "thinking the unthinkable" that think tanks did best at, realizing that there would in fact be survivors in almost any conceivable nuclear war and that one shouldn't simply close one's ears to the possibility because it was horrific. On the other hand, Lynn Eden at Stanford has recently published a book (''Whole World On Fire'') which in my mind conclusively demonstrates that the think tank theorists did not adequately take into account the fire effects of bomb shots, concentrating instead only on blast, heat, and radioactive effects, and in that sense probably severely underestimated the effects of nuclear weapons on inhabited areas. --[[User:140.247.250.21|140.247.250.21]] 17:38, 6 February 2007 (UTC)
:They definitely tested the results of atomic blasts against a Mosler bank vault during their civil defense-related testing at [[Nevada Test Site]] in 1957 ([http://www.slate.com/id/2122382/slideshow/2122433/ it is still there]). These tests were done in the context of houses and facilities not at the epicenter of the blast, but some distance away. The assumption was that the world would in fact not end in such a salvo (and in the 1950s there were not enough warheads to really be "world-ending" in the possession of the USSR) and that things like material property would still be quite important. This was two decades before the so-called "neutron bomb" was developed. --[[User:140.247.250.21|140.247.250.21]] 17:35, 6 February 2007 (UTC)
perhaps the original poster means the economy as opposed to the actual money, i could see governments taking lots of interest in disaster secanios and what would happen to prices etc --[[User:137.205.79.218|137.205.79.218]] 09:08, 8 February 2007 (UTC)
== Job requirements: Spectroscopy and chromatography ==
I have an interview for a [[Cooperative education|co-op job]] that asks for knowledge of [[ultraviolet-visible spectroscopy]] and [[infrared spectroscopy]], as well as [[gas chromatography]]. Now, I have experience with spectrophotometry and spectroscopy, but not specifically UV/VIS nor IR. Also, I have done [[paper chromatography]], but not [[gas chromatography]]. This one seems more complicated .
My opinion is: spectroscopy is spectroscopy is spectroscopy. Am I being cocky, or are UV and UV-VIS quite different from regular (emission / absorption) spectroscopy?
Also, gas chromatography '''seems''' much more complicated than paper chromatography. Are these techniques that I can quickly learn, considering my previous experience? − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 06:53, 6 February 2007 (UTC)
:uv spectroscopy is a type of electronic emission/absorbsion spectroscopy.
:[[Gas chromatography]] (see http://www.gchelp.tk/ from that page for help) is more complicated than paper chromatography.
:My guess is that they would like people who have experience operating uv spectra machines and gas chromatograph machines.
:If you've used any spectroscopy machine (eg IR spec) before then using a iv or uv/vis machine should be simple for you to grasp - there's not a big difference in the way they are set up.
:Gas chromatography is more complex - there's an oven, temperature control, it all depends on how much you are expected to do - just running a spectra would be simpler than setting up the machine, which in turn is simpler than knwoing how to set up a machine for a given sample. I'd expect at least some training - but anyone with experience would probably get first choice..
:Recommend you read the two links above for GC and good luck. That's the best I can offer.[[User:87.102.37.127|87.102.37.127]] 07:02, 6 February 2007 (UTC)
::Thank you, that external link is great! If anyone else has some other comments, they would be appreciated. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 08:11, 6 February 2007 (UTC)
== Sodium laurel sulphate and sodium laureth sulphate. ==
I was just wondering... what are sodium laurel sulphate and sodium laureth sulphate and what do they do? Either one of those chemicals seems to be one of the first ingredients listed on all my shampoo bottles. --[[User:Candy-Panda|Candy-Panda]] 09:37, 6 February 2007 (UTC)
Both are detergentia or tensides or simply spoken soap. --[[User:Stone|Stone]] 10:43, 6 February 2007 (UTC)
[[Sodium laureth sulfate]] might help.--[[User:Stone|Stone]] 10:45, 6 February 2007 (UTC)
:Also [[Sodium dodecyl sulfate]] is sodium lauryl sulphate - they are quite similar - but not the same. Note detergent is a better term than soap - [[soap]] is typically [[Sodium tallowate]] or very similar - as found in a bar of soap. Sodium laur-- sulphates are more likely to be found in a liquid detergent such as [[Fairy Liquid]].[[User:87.102.13.26|87.102.13.26]] 14:06, 6 February 2007 (UTC)
:They're the primary cleaning agents in shampoo.[[User:87.102.13.26|87.102.13.26]] 14:06, 6 February 2007 (UTC)
== 1,3 butadiene ==
Do you have any information about a plant in India and Poland manufacturing butadiene from ethanol by two step process?
:[http://pubs.acs.org/cgi-bin/abstract.cgi/jacsat/1949/71/i05/f-pdf/f_ja01173a084.pdf JACS paper 1949] might be an old process?--[[User:Stone|Stone]] 11:59, 6 February 2007 (UTC)
::[[Ethanol]] to [[actaldehyde]] to [[crotonaldehyde]] to [[butadiene]] with Ta<sub>2</sub>O<sub>5</sub> at 350°C. The paper was first hit in google scolar with ''butadiene from ethanol''
== Heart deposits ==
Suppose you had HDL deposits in your heart, and you were to have a totally fat free diet,
would they then melt away??
Fat is synthesized in our body! HDL free or better cholesterol free would also not benefit, because it is a key component of cellmembranes.--[[User:Stone|Stone]] 13:06, 6 February 2007 (UTC)
:[[High density lipoprotein]] (HDL) is the so-called "good cholesterol". A totally fat-free diet would be quite unhealthy, as fats are required! For example, they help in hormone production and the digestion of vitamins A, D, E, and K. Check out the article on [[essential fatty acid]]s. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 14:04, 6 February 2007 (UTC)
== Acidity level of free fatty acids from waste cooking oil ==
Greetings,
How to check the acidic and content level of free fatty acids from waste cooking oil WITHOUT going thru lab tests..?As in..Can we use cetain chemical or device which we can test on our own...?
A flask some [[phenolphthalein]], [[pipet]], [[sodium hydroxide]] solution of a known concentration, and you can start your job. [[Titration]] os simple!
:I would have liked to have said that but oil doesn't mix with water - making the titration most difficult.[[User:87.102.13.26|87.102.13.26]] 15:42, 6 February 2007 (UTC)
::Mixtures of alcohols help!--[[User:Stone|Stone]] 17:52, 6 February 2007 (UTC)
== Wellbrutrin ==
I read that Wellbrutrin increases sexual urges in women. How does this happen?
:It could suppress inhibitions. [[User:Corvus cornix|Corvus cornix]] 16:52, 6 February 2007 (UTC)
I think I would have to disagree. I believe that something chemically is happening...
for info on stuff like this check here http://people.howstuffworks.com/valentines-day.htm
and for more percise info on it check here http://health.howstuffworks.com/aphrodisiac.htm
[[User:Maverick423|Maverick423]] 17:41, 6 February 2007 (UTC)
Does anyone know what takes place chemically?
Speculations on what takes place chemically are located on the http://health.howstuffworks.com/aphrodisiac.htm article. however i dont think anyone knows forsure what happens with aphrodisiacs because there are alot of factors to consider.[[User:Maverick423|Maverick423]] 18:27, 6 February 2007 (UTC)
The thing is is that this is a anti-depressant, as in the description under Bupropion in Wikipedia: "Patients who complain of sexual dysfunction as a result of their SSRI have sometimes been prescribed small doses of bupropion, amphetamine or methylphenidate to correct it.[5]" Does anyone know how chemically this is affecting the human body?
:A 2006 article ({{doi|10.1093/annonc/mdl304}}) notes "The mechanism by which bupropion has prosexual effects is unknown." [[User:DMacks|DMacks]] 19:54, 6 February 2007 (UTC)
:::Does anyone else find this question a bit creepy? − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 07:06, 7 February 2007 (UTC)
This is for Twas Now, I am the female who typed this question, is currently taking Wellbutrin and experienced the side effect mentioned in the question. There is absolutely no reason for you to underestimate my intention to gain more knowledge. I find you creepy for thinking so! In the future, I suggest that you do NOT answer anybody else's questions because no one appreciates your stupid comments!
:Yes, I bet you are female. How did I underestimate your intention to gain more knowledge? Through the process of questionizationing? Oh I love verbal superfluousness.
:Check out our article on [[bupropion]] (a.k.a. Wellbutrin) and please remember to sign your questions with the <nowiki>~~~~</nowiki> tag. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 10:13, 8 February 2007 (UTC)
'''Twas Now (or never), you must be a womanizer or maybe you hate your mother but, again, I asked that you NOT contribute to this question. If you have any reading comprehension skills, you will see that I had already reviewed the article on bupropion in Wikipedia and, had you read such article, you will see that it doesn't, like you, answer my question. I also will like to know where I could submit a complaint on this forum.'''
:I didn't know that was your comment, since you forgot to add four ~'s to sign your name (<nowiki>~~~~</nowiki>). Anyway, have a look at [[Wikipedia:Resolving disputes|Wikipedia's suggested dispute resolution procedure]]. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 14:27, 8 February 2007 (UTC)
== How to make? ==
Asked this question on the nitrocellulose page however seeing as how people dont really respond to them on there im asking it here .
how do you make gun cotton or where can i get flash paper and is it possable to make flash paper??
: buy it from magic or theatrical effects suppliers. Try searching on "flash paper" +cotton +cord --[[User:Wjbeaty|Wjbeaty]] 02:13, 8 February 2007 (UTC)
the reason for this is for a film me and some friends want to make however we cant find flash paper (not even in magicians stores)
Also how does one go around making that [[Fireball]] from flash paper? you know the one that looks like its a supernatural power comming from the persons hand? in anyways thanks in advance !!!
One more thing whats the safest distance to be at when making a fireball from your hand? (in the term of the other "object")
[[User:Maverick423|Maverick423]] 17:33, 6 February 2007 (UTC)
:My heart bleeds for you! When I was a kid, I read books on how to make home-made explosives, rocket fuel, etc. I ordered flash paper through the mail, and I made my own guncotton. In this day and time, I wouldn't touch your request with a ten foot patch cord... :) --[[User:Zeizmic|Zeizmic]] 17:55, 6 February 2007 (UTC)
::The synthesis is easy, but dangerous. The ingrediants are hard to get and even harder to dispose. And if you really search for it you will find a good synthesis description from a person which is careless and stupid enough to distribute it over the net.--[[User:Stone|Stone]] 18:03, 6 February 2007 (UTC)
*crys on Zeizmic's sholder" WHY!!!!! man dude your lucky! i remember just once seeing flash paper in a magic shop but the store closed down. So with what you state i take it that the substance is now illegal right? Darn! but still i just wanted to know how to make it so ican show the real deal on that short video we are ganna make instead of adobeing it :( so i take it there is no or little chance that i will find this info anywhere eh? and i suppose u cant just buy the ingredients (as it was stated is hard to get) and just mix them up (as far as i know mixing chemicals without knowing the true danger is a death warrnt in itself) in a bucket or something [[User:Maverick423|Maverick423]] 18:13, 6 February 2007 (UTC)
Yep, if you read [[nitrocellulose]] (redirect from [[gun cotton]]) you'll find it explains in some detail how to make it.. including "...very careful preparation of the cotton: unless it was very well cleaned and dried, it was liable to explode spontaneously.." - so maybe it's for the best the ingrediants are hard to get hold of (hopefully).[[User:87.102.13.26|87.102.13.26]] 18:25, 6 February 2007 (UTC)
so its an extreamly unstable compound then... i take it you will need face masks and some sort of protection as a precaution from a accidental explosion then. hmmm but cotton is acctually used? thats intresting. [[User:Maverick423|Maverick423]] 18:32, 6 February 2007 (UTC)
::Explosion is not the problem during production, but a boiling burning nitic acid if the reaction gets a little bit hasty.--[[User:Stone|Stone]] 18:34, 6 February 2007 (UTC)
::The pure compound is quite stable on it's own (in the absence of sparks etc) - but impurities can make the gun cotton unstable. (I think)[[User:87.102.13.26|87.102.13.26]] 18:44, 6 February 2007 (UTC)
::Why are they so distrusting of young folks in the making of explosive and incendiary materials? Oh yeah, now I remember my experiences. The book says make a gram of something and note that it explodes with a pop. I thought that an ounce would be more fun, and it went off with a boom and I was lucky not to lose an eye or fingers. A friend burned down his grandmothers porch (wise enough to take his experiment outside). Fifty or 100 years ago was the golden age of chemistry sets, when the home experimenter could buy literally and reagent. Now kids are taught to be afraid of chemistry and science, except for maybe somesolution changing color. [[User:Edison|Edison]] 18:39, 6 February 2007 (UTC)
::20 years ago I bought a winchester of 98% sulphuric and over a litre of ~70% nitric from a 'pharmacist' - don't think I could do that now.[[User:87.102.13.26|87.102.13.26]] 18:44, 6 February 2007 (UTC)
ehhg tell me bout it i bought a chemistry set with NaCl as the main compound it was very very "cool" at that time now im angered that everyone that was around 20 40 years before i was born had so much more stuff to play with in their chemistry set. and edison is right! in schools they always say (becareful around the lab if you get any liquid on you tell us so we can wash it off even if its just water) i mean comeon thats enough to cause a kid to crap his pants if he gets anything on him. 20 years have gone by for me and the only chemical reactions i have seen is a barbque pit lighting up, fireworks, and water evaporaiting. (of course i seen a bit more but u get my point) [[User:Maverick423|Maverick423]] 18:50, 6 February 2007 (UTC)
There are online stores that sell flash paper -- mostly magic shops and theatrical suppliers. One is at http://www.theatrefx.com/moreinfo_fp01_flash_paper.html -- this is NOT a recommendation, just a site I found by Googling "flash paper." For anyone bemoaning the lack of fun explosive chemistry sets for kids, there's an interesting article from Wired at http://www.wired.com/wired/archive/14.06/chemistry.html.
== God and science ==
Has science disproved God? [[User:Darkhorse06|Darkhorse06]] 18:00, 6 February 2007 (UTC)
::Science can only disproof things which are bound to the laws of physic!--[[User:Stone|Stone]] 18:03, 6 February 2007 (UTC)
you know i always wondered that however i remember one thing
science still hasnt proven or showed how ,that pleage that moses used to kill all the first borns, occored or anything to explain the weird reactions that the pleage had on only targeting the first born and passing over the ones that had blood on the doors. (even though im a man of science seeing things that cant be explained makes me just wonder) [[User:Maverick423|Maverick423]] 18:22, 6 February 2007 (UTC)
:::[[Plagues of Egypt#Historicity]] incidentally. Also, your last sentence suggests you witnessed the plagues yourself. How old are you? [[User:Skittle|Skittle]] 19:55, 6 February 2007 (UTC)
:The existence of an omnipotent deity is (arguably) not within the realm of scientific discovery. Also, from at least some point of view, science cannot "prove" anything to an ultimate degree of certainty. It can only make predictions based upon past observations. These predictions become the laws and theories of science that we use. Theories in themselves can easily be disproved; in principle it takes only one repeatable experiment that disagrees with the theory. We sometimes call theories "laws" when they have been proven time and time again. Science could only "disprove" God if the existence of God made certain assertions or predictions that experiment and observation disagrees with. Whether that is the case depends largely on exactly what a person thinks a belief in God entails.
:Can science disprove that some intelligence caused everything to be? Not really. Taking big bang theory as an example, we cannot answer what there was "before" the big bang, because, in the paraphrased words of Hawking, "that's like asking what is north of the north pole". Science is generally limited to what we can observe and measure somehow. If we cannot observe a god and quantify it, there's very little science can do to prove or disprove its existence. The very basic question is really a philosophical one, so you'll see lots of opinions. Now, as to individual claims that come along with many peoples' ideas of God and creation, those may be answered on a case-by-case basis. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-06T19:47Z</code>
ah sorry about that i didnt intend to make it come out that way. i ment that seeing as how science hasnt figured out what caused it; that gives me doubts about science being correct on evolution and stuff like that. thanks for the link i will start reading it right now. [[User:Maverick423|Maverick423]] 20:23, 6 February 2007 (UTC)
:Evolution is a pretty sound theory that is observable on the small scale. The concepts of mutation, variation, natural selection and adaptation can all be observed in a reproducable laboratory environment. People who claim that evolution is mere postulation are usually under one or more [[Evolution#Misunderstandings|misconceptions]]. Perhaps it's [[abiogenesis]] that you doubt? -- [[User:Matt Britt|mattb]] <code>@ 2007-02-06T20:36Z</code>
::P.S. - If you want to get into the philosophy aspect of this question, [[Existence of God]] does a nice job in covering the high points. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-06T20:20Z</code>
:Science is not ''complete'' and doesn't have all the answers at this time (or even ever for some things), which can be a very unsettling idea. It doesn't mean that what it ''has'' figured out is not well established. And you also seem unsettled by a distinction between ''how'' vs ''what''. People long knew that things fell when dropped even without knowing what was going on. Even ''long'' before anyone had a clue how gravity actually "works", we had the law of gravitational attraction. [[User:DMacks|DMacks]] 20:41, 6 February 2007 (UTC)
Yes i admit im caught inbetween both these issues. the fact that both of them seem real at times is just confusing. god does this and that one person caught in the middle of it is spared while everyone around him dies. science cant explain what happened. yet... it has rumors of what might of happened but they cant confirm it. a higher being? God? or just a series of events that led to the persons survival while everyone else died. like i said its not a very good position to be in when your stuck in the middle. [[User:Maverick423|Maverick423]] 20:59, 6 February 2007 (UTC)
::Yes, the point about completeness is worth remembering. The best scientific theories stand only because nothing has yet proven them to be incorrect. Some of today's theories may be a footnote in tomorrow's science history books. A fun example is that of quantum mechanics (QM) and general relativity (GR), the two principle modern theories of "almost everything". The former describes three of the four [[fundamental interaction]]s observed in nature (electromagnetism, strong and weak nuclear forces) while the former describes the fourth (gravitation). Both theories are widely accepted and are backed by plenty of experimental evidence. The theories also contradict one another; they cannot both be correct and we're not yet sure how to reconcile them (or whether they really can be reconciled).
::I think QM in particular presents a more interesting case. Even if you know everything QM can tell you about a system (let's call it a "wavefunction"), you cannot predict with certainty what the result of a given measurement on that system will be, only probability. This presents an enormous philosophical debate: is quantum mechanics incomplete, and there is some other unknown factor outside QM that determines the characteristics of a system (the so-called realist view) or is there something fundamental about the act of measurement that causes a system to suddenly have a measurable parameter? Some of the greatest human minds have grappled with this and been unable to agree upon an answer yet. Science is constantly evolving and along with it our understanding of the universe; it's hard to say whether everything can be explained with science (another philosophical debate).
::Anyway, I wouldn't feel too bad about being a little bewildered by all this. Nobody even remotely can provide all the answers (save for, perhaps, an omnipotent creature, if you believe in such a thing). Perhaps you'll find some solace in [[The Answer to Life, the Universe, and Everything]]. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-06T21:02Z</code>
Heh thanks much you been quite the help mattb. [[User:Maverick423|Maverick423]] 21:17, 6 February 2007 (UTC)
:I suggest reading [http://www.amazon.co.uk/God-Failed-Hypothesis-Science-Shows/dp/1591024811/sr=1-9/qid=1170797577/ref=sr_1_9/203-0660802-1410319?ie=UTF8&s=books ''God, the Failed Hypothesis: How Science Shows That God Does Not Exist''] for a talk about controlled experiments in search of God. ''[Mac Davis]'' [[User:72.188.92.255|72.188.92.255]] 21:34, 6 February 2007 (UTC)
::It really depends on what you mean, if you mean. God does not 'exist' if you think of the bible or other such documents as theories, then yes, god is disproved, because a theory must be falsified (have proof). While personally I don't believe in a divine being(s), You really should do your own reading. Religion, god, etc, are all taken in faith, and thus, it's something personal, and something you much answer for yourself; does god exist?--[[User:Honeymane|<font color="red" face="Old English Text MT, Papyrus">Honeymane</font>]]<sub>[[User_talk:Honeymane|<font face="Klingon, QuigleyWiggly">Heghlu meH QaQ jajvam</font>]]</sub> 23:18, 6 February 2007 (UTC)
:::Mattb was right in saying that science, or at least [[empirical science]], only works through present and observable events. While it's true that you can't absolutely prove the 10 plagues in Egypt because they're not repeatable events, evolution too falls upon the same rut. You cannot do evolution in a lab, (Although I have heard of scientists have claimed to do this by creating amino acids, which are not life, but merely the ''building blocks'' of life.) Evolution also has a lot of history that lacks evidence (ever heard of [[missing links]]?), putting both viewpoints in a state of controversy. This is because you can ''never'' prove through [empirical] science whether if God existed or not, or if evolution is fact or not because history is ''not repeatable'' through experiments (although you can ''reconstruct'' a past). Does that answer your question?
:::So what, does that mean we can rely on nothing now? Is everything just theory, and no one can ever be sure? Well, if that was true, then we can never prove anything in court, because all events took place in the past. But in a court they have what's called [[beyond a reasonable doubt|proof beyond a reasonable doubt]] (or if you want to do some further reading, read [[prima facie]]), which tells that while there is not enough evidence to absolutely prove something, it is enough to hold up in a court of law. However, there are [[Creation-evolution_controversy|a lot of arguments for both sides]].
:::Those who support evolution quote of differentiation within species through [[allopatric speciation]]; those who support creationism (God created the world) ask why [[punctuated equilibrium]] relies on evidence of 'no change in species' to support that 'species do change'. Those who support God's existence quote first hand accounts of answers to prayer; those who reject this belief ask why can't people believe that was merely a 'freak accident'. Basically, both sides say that they're right. Yet what it really boils down to is not "which argument is right", but "which argument is more logical". Therefore, the court of law illustration is probably not the best one for this case, but a better one may be is two kids arguing about their past. '''So the answer is no, science cannot disprove God.'''
:::I hope I have answered your question thoroughly enough. For anyone who wants to know, I believe that God's existence is more logical. However, I have tried to provide sufficient evidence for both arguments, but if you do find any flaws to my answer, tell me, I'm not perfect. <big>(</big>As entertaining is the thought of having God answer questions on the Reference Desk, Bible text indicates Jesus wants you to receive Him personally [http://www.biblegateway.com/passage/?search=John%201:12&version=50]. :) <big>)</big> I hope this helps, Darkhorse.--[[User:JDitto|JDitto]] (''[[User_talk:JDitto|talk to me!]]'') 03:36, 7 February 2007 (UTC)
::::Not meaning any disrespect, but your post indicates that you yourself are under several common misconceptions about what evolution is and what it asserts. Evolution and abiogenesis are different concepts, as I indicated earlier. It's untrue that evolution cannot be observed; it has been observed on many scales, from viruses to fruit flies. Further, you seem to be treading the line of misunderstanding what "theory" means in the scientific sense.
::::Please don't take this as an attack, I mean no ill will whatsoever. It's just that it really helps to be as informed as possible when discussing this subject. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T05:24Z</code>
::::It is rather natural for people to latch onto the idea that we can use reason and logic to decide what is true. Through millions of years of biological evolution, our brains have been crafted to do a good job of making such decisions about questions like: "Who has more bananas, Og or Urk?" Philosophers such as [[Ludwig Wittgenstein|Wittgenstein]] have made the point that we easily get ourselves in trouble by using our intuitions, logic and reason to deal with abstract ideas that exist beyond the reach of objectively verifiable data. Proof is just an argument that other people accept. [[Carl Sagan]] suggested that we should all practice skepticism and apply this rule of thumb: "Extraordinary claims require extraordinary evidence." --[[User:JWSchmidt|JWSchmidt]] 05:18, 7 February 2007 (UTC)
:::::Here's another philisophy: we can always use reason and logic to decide "truth". The question of God however, falls outside of truth. truth has rules. Omnipotence has no rules and is therefore not subject to truth. The existence of God is a claim of Faith, not a claim of Truth. --[[User:Tbeatty|Tbeatty]] 05:26, 7 February 2007 (UTC)
:To be valid, scientific theories have to be testable. The test may not be possible technologically, but it must be conceivable and not contradict the theory it is trying to prove. For example, the Theory of Relativity postulated certain relationships velocity, mass, time, energy and the speed of light. Actual measurements were then compared to the theory, which corroborated it. It is not "proved" but the lack of disprrof as well as it's ability to predict future events makes it science. In this context, the existence of an omnipotent being is non-testable because the outcome will be whatever the omnipotent being chooses (the beauty of being omnipotent). This simply moves the "question of God" out from being a question of Science to a question of Faith. They are complementary questions, not competing ones. --[[User:Tbeatty|Tbeatty]] 05:26, 7 February 2007 (UTC)
:My own personal observation about evolution is that it is currently mostly an observable. Certainly there are genetic inheritance theories which have both testable, predictive value. But a lot of evolution is simply an obervable of current events. Much like the knowledge that an apple will fall from a tree and it occured long before Newton had his theory. Evolution has almost no predicitve value. Natural Selection is an obervable, not a theory. Sceintifically, we have no idea why certain species were "selected." We simply rationalize what is here vs. what is not but we can't predict what a future adaptation will be. What will the next predator on the Serengeti look like? What will the prey look like? We use the observables of extinct species and non-extinct species to try to identify what the distinction was, but we really have no way to predict what future species will out compete its neighbors. We only look in hindsight. If Hyenas live while Lions die we will look at distincitons and make broad claims. If lions live and hyenas die, we will rationalize their survivor traits. But we currently can't predict what Natural Selection means and what survivor traits are, only that some survive and some don't. We make up the rhyme and reason to fit the facts. --[[User:Tbeatty|Tbeatty]] 05:26, 7 February 2007 (UTC)
::Nicely put. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T05:45Z</code>
:::[[Richard Dawkins]]' God Delusion has a chapter on why God is improbable (i.e. highly unlikely) and points out the fallacy in assuming that because two things cannot be proved 100% they must be treated equally. For example, noone can prove that fairies aren't pushing things down to cause gravity, but it's very unlikely, if it had been written down in a book nearly 2000 years ago people probably would believe it though! When it comes to something like the biblical plagues mentioned above. The statements made show the problems in disproving God. The Bible can make a statement about what God or Jesus did which is scientifically impossible. A sceptic might say science has proved this is impossible and therefore disproved God as described in the bible. A believer might say science can't explain this, therefore science is wrong (taking the truth of the bible as given). So how is it possible to prove or disprove God in these circumstances? But to me the likelihood of some supernatural being creating things seems much more unlikely than any scientific explanantion, when most of the evidence for God seems to be an old book, tradition and the fact that science isn't 100% perfect.[[User:137.138.46.155|137.138.46.155]] 08:17, 7 February 2007 (UTC)
^^^ This made me remember about a old show i saw once. in it they brought up a question that stated something like this " was it god that created man or man that created god?" it does make me wonder like IP dude stated above all the proof of god is an old book. man could of created god to belive in something that something else something greater is out there. they might of used this as a way to explain how they came to be and now that science has found the truth they refuse to belive it because man is stubborn. BUT like i stated before i still have doubts about it but well we can only move forward and see what comes out of it [[User:Maverick423|Maverick423]] 14:34, 7 February 2007 (UTC)
:A lot of people seem to be ignoring the fact that the Judeo-Christian view of God isn't the only one. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T17:31Z</code>
== [[Pet rat]]s and [[Guinea pig]]s ==
What are the chief behavioral differences between [[pet rat]]s and [[guinea pig]]s? --[[User:Andreas Rejbrand|Andreas Rejbrand]] 21:22, 6 February 2007 (UTC)
== Search engine syntax ==
If I want to look for [[Martin Luther]] rather than [[Martin Luther King]], what should I do? Let's say I want to list all ML-only, MLK-only and ML+MLK web pages, how do I do it? I just want to know it this is possible. This question is not specific to any search engine or database service (''e.g.'', Internet and other proprietary databases). -- [[User:Toytoy|Toytoy]] 21:23, 6 February 2007 (UTC)
:"-King" without the quotes should be what you're looking for. Most search engines will exclude results containing a word with a minus in front of it. Additionally, putting a plus sign in front of a word will force results to contain it. You can also force the exact phrase to be searched for by putting it in quotes, as in "Martin Luther", but that may still pull up results about Martin Luther King if king has not been explicitly excluded. [[User:Cyraan|Cyraan]] 22:04, 6 February 2007 (UTC)
:''-King'' or more specifically ''-"King Jr."'' will typically exclude all references to the man who "had a dream". The easiest way to look ''only'' for King is to search for, in quotes, ''"Martin Luther King"''. This will require "King" to be next to Martin Luther as a complete phrase. To get both, just search for "Martin Luther", but be aware that different search engines will optimize this differently (Google will return primarily hits about Martin Luther, not MLK, because of the way it indexes terms). --[[User:24.147.86.187|24.147.86.187]] 23:51, 6 February 2007 (UTC)
It is possible to retrive "Martin Luther"-only entries: <CODE>"martin luther" AND NOT "martin luther king"</CODE>.
:''-king'', so search for ''Martin Luther -King'', and in the unlikely event you get results for people names Martin, and people named Luther, use ''"Martin Luther" -king''. On almost all search engines, putting a minus in front of a word will force it to exclude results that contain that word. [[User:Cyraan|Cyraan]] 05:00, 7 February 2007 (UTC)
How do I retrive "Martin Luther King"-only entries? <CODE>"martin luther king" BUT NOT "martin luther"</CODE> will return nothing! I mean only "King" can go after "Martin Luther". -- [[User:Toytoy|Toytoy]] 04:52, 7 February 2007 (UTC)
:Put it in quotes, ''Martin Luther King'' will search for all of the words, no matter their placement on the page or order, putting it in quotes like this: ''"Martin Luther King"'' forces it to search for only that phrase, and only in that word order. [[User:Cyraan|Cyraan]] 05:00, 7 February 2007 (UTC)
:: No "Martin Luther King" would retrieve entries with both "Martin Luther King" AND "Martin Luther". Example: "In 2000 B.C., Martin Luther King drove a second-hand Toyota to Nepal to visit Martin Luther." -- [[User:Toytoy|Toytoy]] 05:04, 7 February 2007 (UTC)
:::Hmm, what search engine are you using? ''"Martin Luther King"'' on google doesn't turn up any results on Martin Luther for at least the first 5 pages (as far as I looked). On any engine I've used, using quotes forces only results that match the quoted phrase exactly to show up, if it doesnt have ''"Martin Luther King"'' in exactly that order, and containing every word, its not shown. ''"Martin Luther"'' might pull up both because both would match the quoted criteria, but thats where ''-king'' would come in. [[User:Cyraan|Cyraan]] 05:05, 7 February 2007 (UTC)
::::I think the question is about pages that have both the strings "Martin Luther King" and "Martin Luther <X>" where <X> is anything other than "King". I think the answer is "you can't exclude these" (when looking for "Martin Luther King") and you probably don't want to, either. Searching for "Martin Luther King" will find pages that have this exact string on them, as well as pages that have this string AND other occurrences of "Martin Luther ''not King''" and "Martin ''not Luther King''" and "''not Martin'' Luther King" and "''not Martin Luther'' King", but all of them will have at least one occurrence of "Martin Luther King". -- [[user:Rick Block|Rick Block]] <small>([[user talk:Rick Block|talk]])</small> 05:37, 7 February 2007 (UTC)
== physics books ==
What is the best physics books escpecially in quantum physics for engineering ascpects?[[User:84.36.150.67|84.36.150.67]] 22:57, 6 February 2007 (UTC)mostafa elashram
:Best is certainly a superlative. What criteria would you have us consider? If you're interested in QM (I'm assuming you don't yet have a solid grounding in the theory), a good introductory book is "Introduction to Quantum Mechanics" by David Griffiths. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T03:11Z</code>
::P.S. - What field of engineering are we talking about? I'm a semiconductor person on the engineering side, but I can't think of too many other non-physicists outside the realm of semiconductors that would need to use QM regularly... Nuclear engineering, perhaps? -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T03:18Z</code>
:::Material Sceintists working on solids (i.e. superconductors, carbon tubes, some polymers) use QM quite regularly. Optical engineers and people working on lasers use QM quite regularly. --[[User:Tbeatty|Tbeatty]] 06:29, 8 February 2007 (UTC)
::::Optical engineers might as well be physicists... -- [[User:Matt Britt|mattb]] <code>@ 2007-02-08T17:19Z</code>
== Rockoon ==
How powerful would a [[Rockoon]] have to be to reach the ISS? Lets say it was launched from 50Km and it was using todays technologies.[[User:67.126.140.7|67.126.140.7]] 00:08, 7 February 2007 (UTC)
:What do you mean "how powerful?" How much payload do you want it to carry to the ISS? Or do you just want to know the required [[delta-v]]? --[[User:Robert Merkel|Robert Merkel]] 07:41, 7 February 2007 (UTC)
Saying I want to carry 12 tons of material to the ISS is the energy required the delta-v?
== lightning ==
Where does lightning come frome?
Aidan Age 9
:I suggest reading our article on [[Lightning]]. [[User:Splintercellguy|Splintercellguy]] 00:51, 7 February 2007 (UTC)
::In a nutshell, lightning is the result of an electric charge buildup in the clouds. When charges are separated (the Earth itself has a charge), there is an [[electric field]] between those charged bodies. Once the electric field reaches a certain critical strength, the medium that separates the charged bodies (mostly air) breaks down (ionizes), creating a conductive path on which the charge may flow. This ionization and subsequent rapid current flow is what you see as lightning. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T03:09Z</code>
== Reaction to rice...? ==
I have this strange reaction to [[rice]]: Whenever I cook a bowl of rice and add a can of vegetables or tuna or especially when I eat the cooked rice by itself it gets stuck in my [[Esophagus]] or if it makes it down gives me violent and quick sucession [[hiccup]]s. What is going on? [[User:71.100.10.48|71.100.10.48]] 01:53, 7 February 2007 (UTC)
:It would be helpful if you could elborate a bit more. Food getting tempoerarily stuck in the esophagus on its way down is a very common occurance (eating too fast, or trying to swallon too big lumps of food). If you've accidentally got sticky rice instead of normal rice, then i wouldn't be surprised at all. Hiccups is also a very common occurance, and generally do occur in quick sucession. Eating too fast also commonly gives people hiccups. I can't really see anything particularly strange in what you have described. --[[User talk:Yaksha|<font color="#330066"><b>`/aksha</b></font>]] 05:36, 7 February 2007 (UTC)
*It could also be the result of something psychological. Do you like rice? If you don't, your dislike of the stuff is probably part of the reason why you're reacting this way. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 11:24, 7 February 2007 (UTC)
I guess at a sticky rice theory - When I've boiled rice I often 'fry' (it's more like just heating through) in a big pan with a small amount of butter or oil - this really helps separate the grains - you could try that - and see if it still sticks. Hiccups often means you are eating too fast or swallowing too big mouthfuls - I get them all the time.[[User:83.100.251.239|83.100.251.239]] 12:26, 7 February 2007 (UTC)
== Car B has 5 times the mass of car A... ==
Car B has 5 times the mass of car A and car B has kinetic energy 25 times the kinetic energy of car A. What is the ratio:(speed of car B)/(speed of car A)
02:09, 7 February 2007 (UTC)
:I do not think they answer test or homework questions on this board. [[User:71.100.10.48|71.100.10.48]] 02:20, 7 February 2007 (UTC)
:Kinetic energy is calculated using E=1/2 mv^2m, which is 0.5 multiplied by the mass, multiplied by the square of the velocity. Try to work it out from there. --[[User:Bowlhover|Bowlhover]] 03:12, 7 February 2007 (UTC)
::A prettier version: <math>E = \begin{matrix} \frac{1}{2} \end{matrix} mv^2 </math> --[[User: Antilived|antilived]]<sup>[[User_talk:Antilived|T]] | [[Special:Contributions/Antilived|C]] | [[User:Antilived/Gallery|G]]</sup> 11:06, 7 February 2007 (UTC)
== why is there no native human population in Antarctica? ==
Is it because it is simply too cold or infertile for human life, or is it because there were simply no humans there when continental drift occurred? [[User:The Mad Echidna|The Mad Echidna]] 02:50, 7 February 2007 (UTC)
:Well a) continental drift is still occurring; but b) the answer is (your) a. Humans had not yet evolved by the time [[Antarctica]] was split off. [[User:Anchoress|Anchoress]] 02:58, 7 February 2007 (UTC)
::Also, since Antarctica is such a harsh environment, with little flora and fauna, even if there had been humans on it when it separated from the other continents, there is a good chance they would have died out as it drifted further south towards its current ___location, and its climate and ecosystem became progressively more inhospitable. [[User:Maelin|Maelin]] <small>([[User talk:Maelin|Talk]] | [[Special:Contributions/Maelin|Contribs]])</small> 03:52, 7 February 2007 (UTC)
:Your guess is as good as any. The reality is that if there were people in antarctica and the question was "How did people evolve in Antarctica?" there would be just as valid scientific answers as the variables and permutations on life are nearly infinite. --[[User:Tbeatty|Tbeatty]] 05:53, 7 February 2007 (UTC)
:Antarctica broke apart from South America about 23 [[mya]]. Modern humans only evolved around 100,000 years ago, and the split between what would eventually lead to [[human]]s and [[chimpanzee]]s occurred 6 mya. In fact, according to [[Richard Dawkins|Dawkins]]' ''[[The Ancestor's Tale]]'' it was only 25 mya that humans, chimps, [[gorilla]]s, [[orang utan]]s, [[gibbon]]s, and [[Old World monkey]]s all shared a common ancestor! − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 06:57, 7 February 2007 (UTC)
::Hawaii is newer than Antarctica and has people. They came by boat. I believe the latest genome studies show a "necking" in species which corresponds to a near die out (i.e. a very concentrated population) in the recent past. I don't think the species has been around long enough to support a theory that continents broke off and isolated people (but this is just a guess). I think it's more likely that constant growth away from the center created trait reinforcements. But rarely was isolation a barrier to establishing human cultures. Plenty of islands and continents are inhabited by migration either over land or by boat. --[[User:Tbeatty|Tbeatty]] 06:23, 8 February 2007 (UTC)
:::You are right, Hawaii was only colonized about 1,500 years ago—something I always find remarkable! However, I made the implicit assumption that, though it has been ''possible'' to sail to Antarctica for probably thousands of years, it is highly ''improbable'' that, since the evolution of modern humans, one would sail to Antarctica '''and''' decide to stay there, along with a group large enough to perpetuate the intrepid colony until modern times. It was improbable that Pacific islanders would sail to Hawaii, but once this event did happen, there was incentive to stay since the Hawaiian islands can support diverse macroscopic wildlife (both plants and animals), as opposed to lichen, rotifers, and penguins. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 10:25, 8 February 2007 (UTC)
These are the same reasons why noone should have been living on australia until recently, but they were
== electromagnetic pump ==
What equations govern the force exerted by a magnetohydrodynamic (electromagnetic) pump on the fluid running through it?
:The Lorentz force is a good starter. <math>\vec F = q(\vec v \times \vec B)</math>. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T05:14Z</code>
== Basis for claims about the economic cost of poor eyesight (among other things). ==
I heard once on the radio that poor eyesight costs the Australian economy something like $1 bn. a year, or something like that (it may have been in the 100s of millions instead). How do people work out the economic costs of things like that? [[User:The Mad Echidna|The Mad Echidna]] 07:24, 7 February 2007 (UTC)
:They buy glasses, and a new industry is born! Are you referring to the cost of eye care or the cost of incidents directly caused by less than optimal visual acuity? --[[User:66.195.232.121|66.195.232.121]] 15:14, 8 February 2007 (UTC)
::Yes, this refers to the economic costs of having poor eyesight. Economists are very talented guessers, who know how to use simple mathematics in order to substantiate their assumptions. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 15:21, 8 February 2007 (UTC)
== Just pulled out my bird's tail feathers by mistake ==
I was just trying to catch my [[budgie]] to give him his eye drops when I accidentally pulled out most of his tail feathers. He doesn't like being picked up and he flutters/runs all around his cage to get away from my hand. He's very quick. I thought I had him but he managed to slip through my fingers as my grip closed on him, so I only had him by the back end. He pulled away before I could reposition my hand, leaving me holding his long tail feathers.
The tips of the feathers have blood on them and he squeaked in pain when they came out but he's not bleeding from his body. He's just sat there looking unhappy now, giving me evil looks, shaking his backside and preening a lot.
Will his tail grow back eventually? --[[User:84.64.216.148|84.64.216.148]] 08:47, 7 February 2007 (UTC)
:According to the article on [[feather]]s, "a bird's feathers are replaced periodically during its life through molting, new feathers are formed through the same follicle from which the old ones were fledged." Do you know the state of the follicle? − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 09:29, 7 February 2007 (UTC)
::No, sorry. I don't want to pick him up again and stress him out today. I wouldn't even know what I was looking for if I did anyway. :( --[[User:84.64.216.148|84.64.216.148]] 10:46, 7 February 2007 (UTC)
:::If there was no substantial bleeding, he should be okay. Birds [[Moult|molt]] at least once a year and new feathers ought to turn up at that time. I actually wonder about the feathers pulling out; it sounds like it happened relatively easily. Maybe it's already molting time where you are?
:::There's a slight risk that your budgie will become habituated to not having those feathers,and may pick them out when they start to grow again, but I think this is a low risk for tail feathers. On the other hand, I could introduce you to one [[Sun conure]] who has become '''very''' habituated to having a naked chest :-(.
:::[[User:Atlant|Atlant]] 13:20, 7 February 2007 (UTC)
What do birds actually need tail feathers for, they don't seem to have any use, so don't worry about them:][[User:Hidden secret 7|Hidden secret 7]] 19:36, 7 February 2007 (UTC)
:Haha, what? How about for steering themselves, and keeping themselves upright in flight? Please don't buy birds, Hidden secret. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 20:09, 7 February 2007 (UTC)
::Yeah, the OPs budgie will steer like a brick until the new feathers grow in (which I'm pretty sure they will - I've accidentally broken/pulled the odd feather from my birds over the years when trying to catch them). Just be careful that he doesn't bang himself on something when he's flying until he figures out how to compensate. --[[User:Kurt Shaped Box|Kurt Shaped Box]] 22:31, 7 February 2007 (UTC)
:A bird's tail feathers perform the same purpose as the [[spoiler (aeronautics)|spoilers]], [[air brake (aircraft)|air brakes]], [[elevator (aircraft)|elevator]], and [[rudder]] of an airplane. --[[User:Carnildo|Carnildo]] 22:34, 7 February 2007 (UTC)
::So, why is it that different species of bird have different sizes and shapes of tail plumage? Compare a budgie's long, flared tail to the short fan-shaped tail of a gull for instance. --[[User:Kurt Shaped Box|Kurt Shaped Box]] 22:46, 7 February 2007 (UTC)
:::A budgie-style long tail would be a real pain-in-the-ass when the gull is sitting on the water.
:::[[User:Atlant|Atlant]] 01:15, 8 February 2007 (UTC)
:::Due to my favourite kind of selection pressure, [[sexual selection]]! [[Peacock]]s and [[birds of paradise]] have beautiful plumage because of selection by females. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 10:33, 8 February 2007 (UTC)
::::Which brings us back to another question of mine - how the hell *do* gulls pair up in the first place, when they seem to live in a state of constant war with every other gull and living thing in the immediate vicinity? The only time gulls seem to interact with other gulls is to fight or chase them away. I've never noticed anything that I could even remotely comprehend as 'courtship behaviour' (unless courtship in gulls involves the cock and hen fighting each other) in these critters. I suddenly start noticing pairs of gulls stood quite close together - and not fighting each other. Then they make a nest and presumably have sex. --[[User:Kurt Shaped Box|Kurt Shaped Box]] 12:09, 8 February 2007 (UTC)
== Meatomy ==
How do you define the medical term, meatomy?
*Try reading [http://fleshwound.co.nz/html/glossary.html this site]. Basically it involves a scalpel and a [[penis]]. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 11:21, 7 February 2007 (UTC)
::(Site doesn't seem to work? I'm not sure if I should be pleased about that!)[[User:83.100.251.239|83.100.251.239]] 14:06, 7 February 2007 (UTC)
:See [[Meatotomy]]. I could be more used to it, but the pictures are ok. 07:06, 8 February 2007 (UTC)
== x-rays ==
i want information of x-rays
*Try reading our article on [[x-ray]]s. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 11:18, 7 February 2007 (UTC)
== green electricity ==
What is the need for using green electricity in place of hydroelectricity? How is it useful? - [[User:Manavsi|Manavsi]] 11:54, 7 February 2007 (UTC)
:Well, there isn't enought hydroelectricity in many regions / countries. Also hydroelectricity isn't *that* green in certain areas - it is suggested that if you are flooding large areas of forest without having cleared away the vegetation then the anaerobic breakdown of it will cause enough methane to be released to offset CO2 savings from the dam for a couple of decades. --[[User:NeilTarrant|Neo]] 12:54, 7 February 2007 (UTC)
::<s>I'd suggest that the total CO<sub>2</sub> available in say 10 square kilometres (is that reasonable for a resovoir) is piddling compared to the savings from the hydroelectric generation..Or look at it this way - if you burnt all the stuff in the flooded area to make electricity - how long would that last at the same level of production of power - it's nothing like decades.[[User:83.100.251.239|83.100.251.239]] 13:11, 7 February 2007 (UTC)</s> Sorry - ignore me I was in unreasonably grumpy mood.![[User:83.100.251.239|83.100.251.239]] 14:05, 7 February 2007 (UTC)
:::It doesn't strike me as unreasonably grumpy! The reservoirs in question as well were (I'm recalling more of the article) those in places like the rainforests (so lots of plant matter) and in areas which only feature relatively shallow grades (so a large area of lands flooded). Plus its not CO2, but the global warming effect of the methane released which is at issue - hydropower is pretty much inevitably preferable in terms of CO2. --[[User:NeilTarrant|Neo]] 14:56, 7 February 2007 (UTC)
:Creating dams is not "green". They flood large areas, which further reduce habitat for flora/fauna of that region. It is like building a giant city all at once. ''[[Limnodynastes]] depressus'' was lost to science for 30 years (thought extinct), because its only known habitat was flooded by a dam. It has since been found elsewhere, but there is very little knowledge of it because nobody knew where it was for a long time. Also, the fact that it could have been completely wiped out because of a single dam doesn't justify it for me. I'm not totally against them, but there needs to be a lot of environmental considerations to take place before it happens. The Australian Greens movement of the present began with the [[Franklin Dam|opposition to an hydroelectric dam]]. --[[User:LiquidGhoul|liquidGhoul]] 14:50, 7 February 2007 (UTC)
::It does not necessarily equal burning the submerged trees all at once. An article in a recent Popular Mechanics or Popular Science or some such told of billions of dollars worth of mature timber submerged but still harvestable after many years under water. The waterlogged and barkless timber can be sawn off at the base after a flotation bag is attached, by a robot submersible with a long chain saw. It is collected by a barge and taken to a sawmill. It goes from being a hazard to navigation when the water level is low, to being a resource, with a special "green" tag added to the final product when the lumber or furniture is sold at retail, so it can be sold at a premium. [[User:Edison|Edison]] 21:38, 7 February 2007 (UTC)
:::Ah the cynic in me gets to come out. It's a truism that all substantial sources of energy in an industrialized country are, by definition, not "green." Therefore, Hydroelectric energy was green until it was built. Wind farms were green until they were builty. Nuclear was green until they were built, etc. --[[User:Tbeatty|Tbeatty]] 06:07, 8 February 2007 (UTC)
== More possible chess moves than particles in the universe ==
I've heard it said that there are possible moves in a game of [[Chess]] than there are particles in the universe. Has anyone else heard this and does anyone know if it is true; it sounds absolutely ridiculous to me but I have no proof.--[[User:Ukdan999|Ukdan999]] 12:20, 7 February 2007 (UTC)
From [[Chess#Mathematics_and_computers]]:
"..the number of legal positions in chess is estimated to be between 10^43 and 10^50, with a [[game-tree complexity]] of approximately 10^123.."
So thats half the question answered. The number of possible moves will be much greater than 10^43.[[User:83.100.251.239|83.100.251.239]] 12:40, 7 February 2007 (UTC)
:But surely there are way more particles in the universe. If there are around a 200-400 billion stars in our galaxy and around 100 billion galaxies in the universe, that's many trillions of stars, each with possible planets orbitting them. So how many particles in a typical star. And that's not even counting all of the asteroids and other bits and bobs floating through space. --[[User:Ukdan999|Ukdan999]] 12:50, 7 February 2007 (UTC)
::I don't know but I'll ask - then the answer will come..
OK assuming most of the mass of the solar system is the sun, and most galaxyies are similar and have suns like are own that gives.. mass of sun = ~2x10<sup>30</sup>kg x ~300x10<sup>9</sup> (suns in galaxy) x ~100x10<sup>9</sup> galaxyies per universe = ~60,000x10<sup>48</sup> = ~6x10<sup>52</sup> kg of matter in the universe... Assuming most of that is hydrogen atoms that gives ~6x10<sup>55</sup> moles of hydrogen = ~6x10<sup>55</sup> x ~6x10<sup>23</sup> (atoms per mole) = 36x10<sup>78</sup> atoms... So thats still less than the number of chess games that can be played - but more than the number of positions..[[User:83.100.251.239|83.100.251.239]] 13:05, 7 February 2007 (UTC)
Now given that for each position in a game of chess there is a maximum of ~150 moves (usually less) the total number of possible moves can be estimated by
moves per position x number of positions
which equals 10<sup>50</sup> x 150 = 1.5x10<sup>52</sup>
That's many times less than the number of atoms, in fact 36x10<sup>78</sup> atoms/1.5x10<sup>52</sup>positions = 2.7x10<sup>27</sup> times less.
ie there are around 2,700,000,000,000,000,000,000,000,000 times more atoms in the universe than there are moves in a chess game (very rough estimate)
You were right.[[User:83.100.250.165|83.100.250.165]] 14:36, 7 February 2007 (UTC)
:According to the article on atoms, there are approximately ~10<sup>80</sup> in the universe. Please remember to do some research before asking questions. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 20:14, 7 February 2007 (UTC)
::It's a fair point you make - but sometimes info is difficult to find - I would have never thought of looking in 'atom' for that - though I did look in 'universe' obviously..[[User:83.100.250.165|83.100.250.165]] 20:18, 7 February 2007 (UTC)
Keep in mind that, when such estimates use the term "universe", they're generally talking about the [[observable universe]]; that is, that part of the universe that's close enough to have been influenced by the same event in the past. There may well be infinitely many particles in the ''whole'' universe. --[[User:Trovatore|Trovatore]] 20:17, 7 February 2007 (UTC)
I don't believe that current scientific theories support that as a possibility, but I could be wrong, and for that matter the theories could also be wrong.
Anyway, I'd just like to point out that the original question referred to the number of possible ''moves'' in a game of chess. This is not a gigantic number. For example, a white rook could start on any of 64 squares and move from each one to any of 14 other squares, where either it won't capture or it will capture one of 5 possible black men, and there are also 2 ways to castle. That's 64x14x6 + 2 = 5,378 possible white rook moves -- actually less because there are some squares where there couldn't be a black pawn to be captured. You could increase the count if you say that rook from a1 to d1 giving check is a different move than rook from a1 to d1, or if you distinguish which rook (according to its original starting point) is moving, or which black pawn is captured, that sort of thing. The total number of possible moves in chess, depending on your definitions, might be something like 100,000 or 1,000,000 or maybe even 10,000,000... but it isn't going to be something gigantic.
The way the gigantic numbers arise is by considering the total number of positions, or even more, the total number of different possible games. Note that these are the numbers quoted above.
--Anonymous, February 8, 2007, 01:18 (UTC).
:"Current scientific theories" do indeed support the possibility of an infinite (and infinitely massive) universe. There's a discussion in the [[observable universe]] article; also, you can look in [[Wikipedia talk:WikiProject Physics]] (or maybe its archives); I raised the question there some time ago. Search for "inflaton". --[[User:Trovatore|Trovatore]] 01:20, 8 February 2007 (UTC)
Thanks for all the responses!
So, to summarise, there are NOT more possible moves in a game of chess than there are particles in the universe. However, there ARE more possible ''games'' of chess than particles in the universe. This seems a lot more realistic to me than the original statement. Thanks again. --[[User:Ukdan999|Ukdan999]] 01:31, 8 February 2007 (UTC)
==No. of particles in the universe==
See [[Wikipedia:Reference_desk/Science#More possible chess moves than particles in the universe ]] Could someone who knows please give us the (estimate of) the total number of particles in the universe. Thank you.[[User:83.100.251.239|83.100.251.239]] 12:56, 7 February 2007 (UTC)
:Google says somewhere between 10<sup>72</sup> to 10<sup>87</sup>. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-07T13:19Z</code>
::Thanks[[User:83.100.251.239|83.100.251.239]] 14:02, 7 February 2007 (UTC)
:[[Observable universe#Matter content]] give a lower-limit estimate of 10<sup>80</sup> atoms in the universe. [[User:DMacks|DMacks]] 14:54, 7 February 2007 (UTC)
== Searching for machine meant for washing biodiesel ==
Where to find or any relevant website to search for high tech machine for washing biodiesel...?
== dynamometers ==
How long do typical racing car engines run over a race weekend?
How many horse power does a typical F1 engine produce during pre-race testing?
How many horse power does a typical saloon racing car produce during pre-race testing?
== some questions about trees ==
A few years ago I decided to grow some trees from seeds, a horsechesnut and some oaks. Both of these are supposed to be deciduous, and since it is winter, none of them should have leaves on. But they do. So I have a few questions about leaves:
1 My horsechesnut tree started growing new leaves at the begining of january. Is there any reason why it would do this? 2 And will it have any effect on the health of the tree? 3 Some of the leaves on this tree haven't opened yet, is it normal for some leaf buds to open weeks after the others? 4 My oak trees have had the same leaves on them since they first grew, shouldn't they fall off every year? 5 These leaves are also sharp around the edges, like holly leaves. Is this normal for this sort of tree?
Seriously, what is going on with my trees?
[[User:Hidden secret 7|Hidden secret 7]] 15:42, 7 February 2007 (UTC)
Hello, is anyone there:? Can't anyone help me with this:([[User:Hidden secret 7|HS7]] 17:44, 8 February 2007 (UTC)
:How's the weather out there? − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 17:48, 8 February 2007 (UTC)
It's snowing a bit:)[[User:Hidden secret 7|HS7]]
:Maybe you have [[live oak]]s. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 18:37, 8 February 2007 (UTC)
1.Could it be that you have had warm winters; not cold enough to cause the leaves to drop off -
2.This can be a problem in some plants as a sudden frost in Feb can kill the leaves harming the plant..
3. Leaf buds not opening - are the trees in pots or in the ground - if they were grown initially in pots and are still in them they might have reach the capacity of the pot - preventing any further leaf developement (root growth not sufficient)
5. Sharp - with points? The oak 'seed' is an acorn right? Just checking. Oak leaves are 'lobed' in my experience - though checking the article [[oak]] reveals that some species can have pointed leaves - see [[Oak#Classification]] - can you clarify - sorry I can't be much help.[[User:87.102.37.185|87.102.37.185]] 18:44, 8 February 2007 (UTC)
We do usually have mild winters, which could have something to do with it:) I don't know exactly what type of oak they are, unfortunately:( And the leaves had already fallen off the horsechesnut, and more grew this year:) But I expect you are right about them being an unusual specis of oak:)[[User:Hidden secret 7|HS7]]
== Why do we have faces? ==
As silly as the headline seems, it is my question.
Most larger lifeforms on Earth have readily identifiable faces. Infants can differentiate between the face ends of animals. It's relatively easy to identify the 'face' of a fly, a spider, a bear, a pig, a flounder, a whale, etc.
How is it that life on Earth evolved with the vast majority of the critter having similar facial structures? Why don't some beasts have their mouths in their abdomens, near the stomach? Or their eyes in the palm of their hands, to raise them higher to see farther? Or their noses in their feet to facilitate tracking?
Why are most animals arranged in the two eyes, nose, mouth conformation?[[User:75.74.243.218|75.74.243.218]] 16:45, 7 February 2007 (UTC)
:Without giving an answer why not take a look at [[Symmetry (biology)#Bilateral_symmetry]] for a few reasons, and don't forget that not all animals have bilateral symmetry.
:Note that the ability to move (with some speed - not crawling like [[starfish]]) demands a streamlined - eg linear shape (fish for example) - by extension to this putting the mouth and eyes at the front makes it more likely to catch food.. So that would be a reason to have mouth and eyes and other sensory organs - at the top/front.
:Note that very slow animals often don't have bilateral symetry and often have the mouth in the middle - hope that helps.[[User:83.100.250.165|83.100.250.165]] 17:04, 7 February 2007 (UTC)
:::A notable exception to your example is [[squid]] and their relatives - there's a lot of squid.. they also seem to match your description of "..mouths in their abdomens, near the stomach? Or their eyes in the palm of their hands.." to a certain extent..[[User:83.100.250.165|83.100.250.165]] 17:40, 7 February 2007 (UTC)
::Consider that the mouth is involved in lots more than just "getting food in, headed towards stomach". See also [[cephalization]]. [[User:DMacks|DMacks]] 17:08, 7 February 2007 (UTC)
It would seem useful to be able to see and smell what you are about to eat. A second eye adds a wider field of vision, [[Stereopsis]] when the two eyes face front as in humans and other [[Predators]], and a spare when one gets injured.[[User:Edison|Edison]] 21:31, 7 February 2007 (UTC)
: There is good developmental and anatomic reasons for why the eyes, nose, ears and mouth (for tasting) are in close proximity to the brain. And there is good reasons for why the brain is found at the end of the spinal cord. Its also a good evolutionary strategy to have your sense organs '''facing''' the direction your move. Add all these together and you get the basic body plan - including the recognisible face - that is found almost ubiquitously in the [[chordate]]s (at least, in ''[[Craniata]]'') and in many invertebrates too. While its most likely that the facial arrangement is homologous (i.e our [[last common ancestor]] has a face like structure), its possible that a similar structure evolved multiple times. When a strategy works, nature tends to favour it (see [[convergent evolution]]). [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 23:35, 7 February 2007 (UTC)
== Space ==
::I've moved this question from [[Wikipedia:Reference_desk/miscellaneous]] so that you are more likely to get a good response...[[User:83.100.250.165|83.100.250.165]] 17:10, 7 February 2007 (UTC)
If a seed is germinated on earth, the roots go down while the leaves reach upward toward the sun, I assume this has something to do with gravity, thus allowing the roots to know where ''down'' is. So, in space, if one were to germinate a seed, a)would it germinate b)would it do so in an effective manner.
And as a second question. Menstration cyles in women are, or so i am told, coincide with the moon, (much like ocena tides) hence every 28 days. How would this be affected in a) zero gravity b)when out of the ''pull'' of the moon and c) if one were on another planet which had serveral moons or (b) no moons.
Thanks guys Mr Anonymous [[User:81.144.161.223|81.144.161.223]] 16:08, 7 February 2007 (UTC)
:I doubt it has so much to do with [[gravity]] as with the [[roots]] seeking [[soil]] [[nutrients]] and the leaves seeking [[sunlight]]. So I imagine that they would do fine in space, see [[hydroponics]]? Just a brief mention there. -- [[User:Justanother|Justanother]] 16:18, 7 February 2007 (UTC)
Question 1. You should look at [[Root#Root_growth]] " At germination, roots grow downward due to [[gravitropism]], the growth mechanism of plants that also causes the shoot to grow upward" - so lack of gravity will be an issue... I can't say more..[[User:83.100.250.165|83.100.250.165]] 17:43, 7 February 2007 (UTC)
:Excellent point. [http://www.ncsu.edu/project/agronauts/iss/project_overview.html Here] and [http://spaceflight.nasa.gov/station/crew/exp6/spacechronicles13.html here] are some links. The first is a proposed experiment and the second an actual, if casual, experiment. In the casual experiment the plants did not grow because [[capillary action]] appeared to be stronger than the reach for light. A substrate might be designed that could negate that effect. --[[User:Justanother|Justanother]] 18:02, 7 February 2007 (UTC)
::From a [[NASA]] chat session[http://quest.nasa.gov/projects/space/iss2001/march/chat040802yb.html]<blockquote>[ Yuli_Berkovich - 216 - 18:00:47 ]</blockquote><blockquote>RE: [ Does gravity affect your plant growth significantly?</blockquote><blockquote>Of course, gravity affect all plants significantly. Fortunately we can replace influence of gravity on root and stem orientation by means of another environmental stimulus: light distribution for stems and water distribution for roots.</blockquote>--[[User:Justanother|Justanother]] 18:09, 7 February 2007 (UTC)
:Regarding the second question, see [[Menstrual cycle#Etymology_and_the_lunar_month]] and [[Menstrual cycle#Menstrual_cycles_in_other_mammals]], and be careful to avoid presuming that correlation means causation. [[User:DMacks|DMacks]] 18:24, 7 February 2007 (UTC)
Related to this, what experiments have been done to test the growth of plants in space? A greenhouse would have abundant sunlight, would help in some small way to convert carbon dioxide back to oxygen, and could furnish tasty sprouts and greens. It would be useful on a Mars mission and probably essential (with artificial light) on interstellar mission, manned stations away from Earth or [[Space colonization]]. [[Biosphere 2]] has experimented with this in an Earth-born environment. What experiments have been done on seed germination and hydroponic gardening, in all of the history of the space program? [[User:Edison|Edison]] 21:20, 7 February 2007 (UTC)
::Well Googling on Yuli Berkovich I came up with [http://space.com/missionlaunches/russia_greenhouse_030819.html this] and [http://ncr101.montana.edu/memberpages/stationreports/2003_reports/naskdyn_2003.pdf this]. Yuli seems to be "Da Man". --[[User:Justanother|Justanother]] 22:14, 7 February 2007 (UTC)
I greatly appreciate your help, and the answer the first part of my question, was very interesting, and thanks goes out to all responsible. However, to come back to the second part of my question. I have read the article on [[Menstrual cycle#Etymology_and_the_lunar_month]] How ever if one looks at the cite, I do not belive this to be conclusive as A) it was done by men. and B) they class their book with the paranormal!?!? There is nothing abnormal about menstration. :
^ As cited by Adams, Cecil, "What's the link between the moon and menstruation?" (accessed 6 June 2006): Abell, George O.; Barry Singer (1983). Science and the Paranormal: Probing the Existence of the Supernatural.
So concerning interplanetary colonization and space expolration in general, could any one help further with the above question? Thanks guys, and Ladies.
== What is it that causes different meat to taste a different way? ==
Hi all, I am wondering why different meat that's unspiced still tastes a different way, ie beef and chicken, pork and fish. I understand that they are in different [[Classes]] biologically, but what is it specifically that alters their taste, in scientific terms? Do different proteins taste differently or what? Much help appreciated ! [[User:Xhin|Xhin]] 18:42, 7 February 2007 (UTC)
:I'm not really qualified to give a full answer but this : http://www.madsci.org/posts/archives/Mar2003/1048043552.Gb.r.html may help..
:It seems then that the [[maillard reaction]] is responsible for causing the formation of certain flavoursome compounds in cooked meat. I'm sure that's not the only factor.[[User:83.100.250.165|83.100.250.165]] 19:38, 7 February 2007 (UTC)
:[[Umami]] might be part of the answer. --[[User:JWSchmidt|JWSchmidt]] 01:48, 8 February 2007 (UTC)
== Alps and Mountains ==
What is the difference between alps and mountains? In Europe there are both alps and mountain ranges; why the dirrence?
:The Alps are a specific mountain range:) But alpine areas are places with mountain like climates and vegetation, usually on mountains:)[[User:Hidden secret 7|Hidden secret 7]] 19:33, 7 February 2007 (UTC)
::"Alp" does mean "any high, especially snow-capped, mountian" [[OED]], but it is mostly used as such only in poetic or jocular contexts these days. The etymology is ''"said by Servius to be of Celtic origin, and variously explained as meaning ‘high’ (cf. Gaelic alp a high mountain, Irish ailp) and ‘white’ (cf. L. albus).]"'' [[OED]]. --[[User:Shantavira|Shantavira]] 08:40, 8 February 2007 (UTC)
:::The description of a mountain range as 'alps' is quite common eg 'altai alps' 'himalayan alps' - I imagine it is necessary for the mountain to have snow on top to truly fit the description..[[User:87.102.2.204|87.102.2.204]] 10:06, 8 February 2007 (UTC)
== Changing Iris Color ==
What are some of the reasons that an iris will change color? Are their any possible ways to change it, say from dark brown to light brown?
:Whilst you wait for a proper answer I can suggest that you look at [[Iris (anatomy)#Color]], and maybe [[Eye color]] - it seems that melanin (as found in hair) is responsible for all the brown colour in eyes - and that it's levels can increase with age.. Also disease may cause an iris colour change..[[User:83.100.250.165|83.100.250.165]] 20:42, 7 February 2007 (UTC)
:Someone (probably a sceptic) has removed my answer:( But I searched on the internet and apparently medical treatment with iodine can also affect iris colour:)[[User:Hidden secret 7|Hidden secret 7]] 20:48, 7 February 2007 (UTC)
:Something that should not have been removed is that you can get contact lenses with different colors.
::Some treatments for [[glaucoma]], such as [[prostaglandin]] analogs, are known to change eye colour in maybe 10% of patients. Its thought that prostaglandin acts on eye colour by mimicing a natural hormone that mediates [[melanin]] production. People have reported that when they are ill or under stress that their eye color becomes darker or lighter. A modified version of the pigmentary hormones are also produced during stress (and when you stress fish and frogs, they change colour for this very reason, see [[chromatophore]]). [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 23:13, 7 February 2007 (UTC)
Just as an aside, I had a friend, Jaffa, whos eye colour would change with his moods, i cant now remember the corrolation but it was for example Brown when happy, green when sad, blue when arroused ect.
Are you sure it wasn't green for worried, black for angry, pink for embarrased...
As I said I dont remember the Emotional colour correlation.
== Spinal cord syndrome by french doctor? ==
I am looking for a french doctor that had a syndrome named after him. The main symptoms were when you bend your head down you get numbing and pain radiating down your arms and legs. I am unsure how to spell his name and need the correct spelling and are also looking for specifics on this syndrome.
:Probably not "[[Maladie de Charcot]], after the French doctor [[Jean-Martin Charcot]]" ??[[User:83.100.250.165|83.100.250.165]] 20:21, 7 February 2007 (UTC)
:I suspect we're talking about [[L’Hermitte’s sign]], named after [[Jacques Jean Lhermitte]] (or [[Jacques Jean L'Hermite]]) - <span style="font-family: cursive">[[User:Nunh-huh|Nunh-huh]]</span> 03:47, 8 February 2007 (UTC)
== Lewis dot structure for XO32- (X = F,Cl,Br,I) ==
For the hypothetical compound XO32-, what would the most reasonable lewis structure be? I can think of two possibilities:
1) Two X-O single bonds, one X=O double bond. The singly bonded oxygens carry a negative charge, and the halogen carries a lone pair and an unpaired electron and is uncharged.
2) Two X=O double bonds, one X-O single bond. The singly bonded oxygen carries an unpaired electron and is neutral, the halogen carries three double bonds and a charge of -2.
Option two requires 16 valence electrons on the halogen and is unreasonable for fluorine. It does place the charge on the most electronegative atom for Cl,Br,I.
I ask this because I have been asked to draw the molecular shape of this compound. Am I correct in thinking both options give T-shaped geometry (making the point moot)? Thanks for comments [[User:132.194.13.115|132.194.13.115]] 20:49, 7 February 2007 (UTC)
:<s>OK before I start you wrote XO32 - did you mean XO<sub>3</sub> or X<sub>2</sub>O<sub>3</sub> ???[[User:83.100.250.165|83.100.250.165]] 20:58, 7 February 2007 (UTC)</s>
:Right did you mean XO<sub>3</sub><sup>2-</sup>..[[User:83.100.250.165|83.100.250.165]] 21:02, 7 February 2007 (UTC)
::If so the theoretical ion is a radical anion, see [[radical (chemistry)]] - in terms of a lewis structure it has an unpaired electron - there are an odd number of electrons.
::I get
:::Three X-O single bonds, each O is singly charged, the X is positively charged and carrys an unpaired electron - it has also expanded it's octet to 9 electrons.. (supposedly impossible for F)
::Each X is bonded to three O's and has 3 electrons remaining - This should give a 'distorted tetrahedral' structure - the O-X-O angle will be the same between all combinations of O. Alternatively the molecule could be a [[trigonal bipyramid]] with O's expected around the middle - giving an O-X-O bond angle of 120degrees.
(see [[Trigonal bipyramid molecular geometry]][[User:83.100.250.165|83.100.250.165]] 21:24, 7 February 2007 (UTC)
Personally I'd look at the effect of adding one electron to the stable structure ClO<sub>3</sub><sup>-</sup> - though I'd be thinking in terms of molecular orbitals - which may not be much use to you? - I'd expect the extra charge to be [[delocalised]] ie the structure would consist of resonant hybrids (see [[resonance (chemistry)]] - and I find it difficult to accurately predict a structure.[[User:83.100.250.165|83.100.250.165]] 22:22, 7 February 2007 (UTC)
== [[Beta particle]] capture surface...? ==
[[Image:Beta particle capture surface.JPG]]
Would the surface shown above provide better capture of [[Beta particles]] than a flat surface and how high a voltage differential would there be between the two plates in a vacumn? (This is not a test or homework question BTW.) [[User:Barringa|-- Barringa]] 21:40, 7 February 2007 (UTC)
:im not an expert on this, but I think there is really no limit (apart from leakage or vacuum breakdown) to the voltage difference that could be created.--[[User:DarkFuture|DarkFuture]] 22:17, 7 February 2007 (UTC)
[[Image:Lightning_rod.png|right|thumb|150px|Nikola Tesla's <br> "Lightning-Protector" <br> {{US patent|1266175}}; An early type of dissipater-arrester, which purported to prevent and safely dissipate lightning strikes]]
::Charge accumulates on sharp points (i.e. areas with small radius of curvature). See [[lightning rod]]. [[User:Nimur|Nimur]] 19:33, 8 February 2007 (UTC)
==Moon east==
From [[Wikipedia:Reference_desk/Science#Reversed West and East on the Moon?]].
What direction is east on the moon - according to astronomers, spacemen, scientists etc.
[[User:83.100.250.165|83.100.250.165]] 21:52, 7 February 2007 (UTC)
:Or if east/west is not used - what system is used to define points on the moon?[[User:83.100.250.165|83.100.250.165]] 22:08, 7 February 2007 (UTC)
:Per [http://simkin.asu.edu/clem/ JPL], the moon has its own system of [[latitude]] and [[longitude]] with the lunar [[prime meridian]] at the center of the [[Near side of the Moon|near side]]. Presumably, the center is averaged to account for lunar [[libration]].
:Of course, there's no telling what [[Extraterrestrial life|spacemen]] might use for a coordinate system. — [[User talk :Lomn|Lomn]] 22:53, 7 February 2007 (UTC)
OK there are multiple ways.. Thanks - not knowing was really starting to irritate.[[User:87.102.2.204|87.102.2.204]] 09:59, 8 February 2007 (UTC)
==Paleozoic marine animal name==
I am trying to remember a name of a Paleozoic marine animal. I'm pretty sure its name starts with "dunkleo-", but I cannot find the remainder of the name, and I do not know how one would go about doing Wikipedia- or Google-searches for partial words. The creature is very distinct-looking for its very strange layer of teeth which appear to be all one jagged structure, like a continuation of the jaw bone. [[User:206.176.113.70|206.176.113.70]] 22:05, 7 February 2007 (UTC)
:[[Dunkleosteus]] - I searched for "paleozoic marine" on google by the way.[[User:83.100.250.165|83.100.250.165]] 22:10, 7 February 2007 (UTC)
== Orbital characteristics ==
In the [[Template:Infobox Planet|planet infobox]], (as used [[Earth|here]] and in other planet articles), under orbital characteristics, four of the parameters are for aphelion, perihelion, semi-major axis, and semi-minor axis. How/why is the first pair different from the second?
--[[User:Superiority|Awesome]] 23:52, 7 February 2007 (UTC)
:The two pairs give two ways of describing the shape of the orbital ellipse. The aphelion and perihelion points are at opposite ends of the major axis, so the aphelion distance (A) and perihelion distance (P) are related to the semimajor axis (a) by 2a = A + P. The minor axis is perpendicular to the major axis and runs through the center of the ellipse (halfway between the Sun and the other focus). The semiminor axis (b) is not a very useful number for astronomical purposes, but it's related to the other quantities by (thinks a moment) a² = b² + ((A-P)/2)². --Anonymous, February 8, 2007, 01:29 (UTC).
== Species and Speciation ==
I thought that the thing separating species was that interbreeding between two different species was either impossible, or would not result in fertile offspring. So how does a new species evolve considering that it could not be the progeny of the species it evolved from? Is my definition of species incorrect? Is it not an absolute? Have I missed something? Is this a problem for the theory of evolution?<small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:129.15.131.247|129.15.131.247]] ([[User talk:129.15.131.247|talk]] • [[Special:Contributions/129.15.131.247|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
:Speciation occurs gradually, and often when a population of organisms is separated into subgroups by a natural phenomenon (e.g. a landslide, or continental drift, or just gradual migration). The subgroups of the population each evolves independently, responding to the pressures of their environment. Over time, they could adapt in different ways, until eventually the genes of one group are no longer compatible with the genes of the other. [[User:Maelin|Maelin]] <small>([[User talk:Maelin|Talk]] | [[Special:Contributions/Maelin|Contribs]])</small> 04:16, 8 February 2007 (UTC)
:First of all, there are [[Species#Definitions of species|several definitions of species]]. You are referring to the "Biological / reproductive" concept. New species would evolve when separate populations of the same species become separated and evolve in different ways. For example, suppose there is a species of fish in a lake, and that lake dries up, leaving only puddles with fish in them. Over time, the different puddles ''may'' evolve different types of fish. When the water levels rise again, and the fish are all together again, there will potentially be more species. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 04:17, 8 February 2007 (UTC)
No, no, I understand the patric speciation and how a group of one species can be split apart for whatever reason and therefore be subjected to different environments, each requiring different adaptations, but within each of those split groups, how would the population change into a new species? Eventually, wouldn't a member of the old species have to give birth to a member of the soon to be new species? What does that member of the new species mate with to increase the population of the new species? Would 2 mutants with similar adaptations and opposite sex have to be born around the same time so that they can increase their numbers? Is there some absolute cut-off point for the possibility of reproduction, or is it instead increasingly improbable that viable offspring will be created from a mating of two different species based on the number of genetic differences, meaning that a human and monkey could in fact create fertile offspring, only that it is a gross statistical improbability?<small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:129.15.131.247|129.15.131.247]] ([[User talk:129.15.131.247|talk]] • [[Special:Contributions/129.15.131.247|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
:Just because organism A is "close enough" to organism B to breed and organism B is "close enough" to organism C to breed doesn't mean that A and C can breed. It's not that one generation is one species and suddenly the next generation is a different one. [[User:DMacks|DMacks]] 05:05, 8 February 2007 (UTC)
:This is where the concept of species is sort of blurry. This excerpt from [[Richard Dawkins]]' ''[[The Ancestor's Tale]]'' (one of my favourites) is what you are asking, I think, but in a different way:
::''If species A evolves into species B, ''[…]'' there must come a point when a child belongs to the new species B but his parents still belong to the old species A. Members of different species cannot, by definition, interbreed with one another, yet surely a child would not be so different from its parents as to be incapable of interbreeding with their kind.'' (pp.255)
:− [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 05:06, 8 February 2007 (UTC)
::If you want Dawkins' subsequent explanations on this, let me know. Oh, and please remember to sign with <nowiki>~~~~</nowiki> after you ask questions. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 05:59, 8 February 2007 (UTC)
@DMacks: Yes, I understand that not EVERY generation (and certainly not consecutive ones) will be a new species, but the problem I'm having is understanding how there will be (seemingly) new species offspring from old species parents, and how these new species, being, by definition, unable to mate with the old species, will be able to expand their population.
:Speciation does not seem to occur absent an outside pressure (change in food sources or predation, environmental barriers to population mixing). In time, separate '''populations''' within a species will adapt to individual niches (perhaps plants located on windward vs leeward mountainsides or insects feeding on a specific local weed). Given enough time, these populations may diverge enough to meet our human-defined criteria for different species. -- [[User:Scientizzle|Scientizzle]] 06:54, 8 February 2007 (UTC)
@Twas Now: Yes, that is a more eloquent way of putting my question. Now, what is the answer?
<nowiki>~~~~</nowiki><small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:129.15.131.247|129.15.131.247]] ([[User talk:129.15.131.247|talk]] • [[Special:Contributions/129.15.131.247|contribs]]){{#if:{{{2|}}}| {{{2}}}|}}.</small><!-- Template:Unsigned -->
::<small>(when signing, don't include the nowiki tags...) -- [[User:Scientizzle|Scientizzle]] 06:58, 8 February 2007 (UTC)</small>
:The answer is that "speciation" is a human construct, and mother nature has done quite well without confining herself to human rules for several millenia. -- [[User:Scientizzle|Scientizzle]] 06:58, 8 February 2007 (UTC)
::Perhaps she has done so for even longer than several thousand years! Whammy! Blammy wowie zowie! − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 07:07, 8 February 2007 (UTC)
:::Quite right, but even young-earthers can agree on "several millenia" :) -- [[User:Scientizzle|Scientizzle]] 07:15, 8 February 2007 (UTC)
::::Yes, I believe it was [[James Ussher|October 23, 4004 BCE]]? − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 08:11, 8 February 2007 (UTC)
:Dawkins explains, that we should "allow for the possibility that an individual might lie half way between two species, or a tenth of the way from species A to species B" (pp.256). He goes on:
::''Are there sharp discontinuities between species, or do they merge into each other like first-class and second-class exam performances ''[referring to [[bell curve grading]]]''? If we look at surviving animals, the answer is normally yes, there are sharp discontinuities. ''[…]'' People and chimpanzees are certainly linked via a continuous chain of intermediates and a shared ancestor, but the intermediates are extinct: what remains is a discontinuous distribution. The same is true of people and monkeys, and of people and kangaroos, except that the extinct intermediates lived longer ago. Because the intermediates are nearly always extinct, we can usually get away with assuming that there is a sharp discontinuity between every species and every other. ''[…]'' When we are talking about all the animals that have ever lived, not just those that are living now, evolution tells us there are lines of gradual continuity linking every species to every other ''[…]'' in lines of smooth unbroken continuity.'' (pp.258-9)
:In other words, an [[essentialist]] view of species is a mistaken view. But a fresher concept of "species" is not what you want to know—so let me take you through some hypothetical steps that would cause two lines of the same species to diverge into distinct species. However, remember to keep in mind this "continuous" view of species.
:#The two populations are separated somehow (often, but not necessarily, geographically separated). For example, one population (A) lives where conditions are moist and fertile, and the other population (B) lives where the climate is dry and barren.
:#[[Selective pressure]]s on the two populations are different. For instance, members of population A may have selective pressure to evolve water-absorbent skin, while members of population B will have selective pressure to evolve water-retentive skin.
:#Other factors, such as [[sexual selection]] are likely to have an effect.
:#After sufficient time, the two species have changed genetically (from their initial species) to such a degree that they can no longer interbreed.
:You may want to look up [[cladogenesis]] (splitting of one species into two) and [[anagenesis]] (change of one species from its ancestral to modern form). I hope this helps—'''and it should!''' − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 08:03, 8 February 2007 (UTC)
Distinct species are unlikely to interbreed, not unable to interbreed. Very often the barrier between two sister species starts of behavioural rather than genetic - ie, they could interbreed, they just don't because they don't recognise each other's breeding display or breed at slightly different times. The [[Apple maggot]] is considered a case of incipient speciation - the flies that lay their eggs on apple flowers are still considered the same species as their cousins who lay their eggs on hawthorn, having developed a taste for apples in only the last few hundred years since Europeans introduced apples to North America. Because apples and hawthorn flower at different times, populations which specialise on one or the other need to emerge at different times and be attracted to different scents. Since they emerge at different times, they tend to breed at different times, so mixing is unlikely, but possible (there is no genetic reason that they can't). If you have one parent of one variety and one parent of the other, you might be lucky and inherit the right set of genes that makes you emerge at the right time and go searching for the right flower, or you might get the wrong combination of genes (and be looking for hawthorn flowers despite the fact that you emerged when apples were in flower). If you have the right pair, you merge seamlessly into that population ([[introgression]]). If you have the wrong pair, you're dead. So there is selection that favours keeping the two populations separate. In the future there might be more changes that gradually become established in one population or the other, resulting in populations that we might call different species. [[User:Guettarda|Guettarda]] 17:42, 9 February 2007 (UTC)
== Vocal Octet ==
Greetings... I searched the wikipedia pages for the vocal octet. What I got was not what I wanted... Isn't the english vocal octet something "do re mi fa so...." I do not remember the whole octet but on the pages here this octet is not talked of. Could someone complete it for me?
:The [[Do Re Mi]] page is a good starting point. [[User:DMacks|DMacks]] 05:47, 8 February 2007 (UTC)
:You are referring to [[solfege]]:
::''Do Ré Mi Fa Sol La Si''
::''Do Ré Mi Fa So La Ti''
:− [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 05:57, 8 February 2007 (UTC)
::Or perhaps you have confused 'octet' with '[[octave]]', which in the vocal tradition is sometimes divided into 8 notes and sung with the syllables you mentioned. --[[User:bmk|bmk]]
:::Well, an octet is any group of eight things, so technically "Do Ré Mi Fa Sol La Si Do" is an octet. It is an octet of the eight [[Ionian mode]] [[interval (music)|interval]]s of an [[octave]]. This discussion might belong at [[Wikipedia:Reference desk/Humanities|the humanities desk]]. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 07:18, 8 February 2007 (UTC)
I think a "vocal octet" would be a group of eight singers. Duet = two singers, quartet = four singers, sextet = 6 singers, so octet should be eight singers. On the other hand, "vocal" can mean "outspoken." A group of eight articulate single-issue citizens forcefully expressing their opinion at a town meeting would be a "vocal octet." -[[User:Arch dude|Arch dude]] 01:14, 9 February 2007 (UTC)
Thanks for the response... [[User:203.187.238.139|203.187.238.139]] 05:06, 9 February 2007 (UTC)
==A question I can't get out of my head==
Hypothetically, if all humans are incapable of feeling/experiencing pain then will we (humans) ever deduce that animals can feel pain? [[User:211.28.131.148|211.28.131.148]] 11:08, 8 February 2007 (UTC)
:You mean capable (not incapable) I think.
:I already have deduced that animals can feel pain - when I stood on a dogs foot (by accident) the noise it made (yelp) coupled with knowledge of what I had just done made it clear that dogs can feel pain.[[User:87.102.2.204|87.102.2.204]] 11:32, 8 February 2007 (UTC)
:Are you asking: ''If humans were incapable of feeling pain, '''would''' they ever deduce that animals can feel pain?'' The swapping of ''would'' and ''will'' makes a big difference in this case.
:* Humans (most of us) cannot use [[echolocation]] but we know [[microbat]]s can.
:* Humans can only hear in the frequency range of 20 Hz to 20 kHz, whereas dogs can hear from about 16 Hz to 45 kHz and cats can hear from about 20 Hz to 64 kHz, etc.
:* Humans can not see infrared, but [[Infrared#Biological systems|some animals]] can.
:Of course, my examples might be different than the hypothetical situation you have proposed, since humans at least '''have''' that sense, only less sensitive. Humans can hear and know of other frequencies of sound, so it wouldn't be a great leap to deduce these things about bats, cats, and dogs. Humans can see and know of other wavelengths of light, so they could also deduce how animals can see infrared. However, it is a completely different thing to say that humans would be able to deduce that animals can feel if humans had no sense of touch whatsoever!
:Just my thoughts. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 11:38, 8 February 2007 (UTC)
I don't think we would be able to deduce that animals can ''feel pain''. However, we would be able to notice that animals had the mechanisms for feeling pain (and also realize that we didn't have them). So for example, we may be able to find [[Nocireceptors|pain receptors]], and deduce that animals can feel ''something'' through them which we can't. However, if humans all humans are incapable of feeling pain, then the concept of "pain" would not exist in our soceity. We wouldn't understand what it was, and we wouldn't really be calling it "pain". And there the question starts getting philosophical... --[[User talk:Yaksha|<font color="#330066"><b>`/aksha</b></font>]] 12:06, 8 February 2007 (UTC)
: Yes. Possibly we would call it [[thigmotaxis]] (or invent a name for it), seeing that animals move away from pain but without realising why (the actual feeling). It is something like how some of the animals are able to sense impending natural disasters but we humans are not able to -- [[User:wikicheng|Wiki'''''Cheng''''']] | [[User talk:wikicheng|Talk]] 13:25, 8 February 2007 (UTC)
Me, I'd say that if humans were incapable of feeling pain, then no, they would never deduce that animals can feel pain, because ''the humans would not exist''.
Pain is a vital mechanism; no animal can fail to experience it in some way. It's a tremendous survival advantage: animals which experience pain can (usually) move away from or otherwise eliminate the source of the pain before their body is fatally damaged. An animal which is in pain due to an injury can take steps to care for itself while it heals. An animal which didn't experience pain wouldn't last long.
There was a long discussion in [[Stephen Pinker]]'s book [[How the Mind Works]] about whether non-humans can "feel" pain, which I thought was silly: of course they can. The only difference is that they don't ''call'' it "pain", but then, they don't usually call anything anything.
There was great line in [[Terminator 2: Judgment Day|Terminator II]] where John Connor asks the Terminator, "Do you feel pain?" (I think this is while the Terminator is having bullets picked out of his back.) The Terminator thinks for a moment and says, "I experience what you would call pain", which I think sums the condition up perfectly. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 01:32, 9 February 2007 (UTC)
Acctually I have done an experiment myself, and using an electric charge monotoring system of sorts, one is able to measure the amont of pain felt by a plant: when i inserted two probes into the stem of the plant, then broke a leaf in half it registered, therefore, we would, and can measure the pain flet by other species, plants, animals ect.
:So what did you measure with your electric charge monitoring system of sorts? How much pain do you deduce that plants feel? Why would you believe that electrical currents in a plant would indicate pain? Why not pleasure? Or humor? Or [[dark current]]? --[[User:bmk]]
:: Scientifically, ''pain'' is separate and distinct from ''nociception''. We can be certain animals experience the latter, but since the former is a subjective experience its open for debate whether animals "feel pain" as we do. See [[Pain and nociception]] for an overview. [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 06:56, 9 February 2007 (UTC)
::: Huh! "Nociception". Whouda thunkit. So my speculations above about animals (and robots) "obviously" experiencing pain were misguided, or at least underinformed.
::: I'm reminded of this little ditty:
:::: There once was a thinker of zeal
:::: Who said, "Although pain is not real
:::: When I sit on a pin
:::: And I puncture my skin
:::: I dislike what I ''fancy'' I feel."
::: --[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 16:32, 9 February 2007 (UTC)
:Well, when you cut a part of a living organism, the feeling, if at all there is one, would be of 'pain' (or agony), unless the living organism enjoys it. So the electric charge measured when a leaf is broken can be classified under pain and not under pleasure. Obviously, the plant doesn't enjoy it's leaf being cut? -- [[User:wikicheng|Wiki'''''Cheng''''']] | [[User talk:wikicheng|Talk]] 08:47, 9 February 2007 (UTC)
== Trichobezoar ==
I'd be interested to know how much (approximately since I realise there is probably no definite answer)hair would an adult have to consume in order to develop a trichobezoar which would pose some risk to their health? Thanks, if anyone has any idea.
== chemistry ==
I need to find the chemical formulas and names and how many atoms are in the following chemicals. CH4, C2H4O2, CaCO3, NH4NO3 do you think that you can get some answers?
:Well you've already given the answer to the first query: the chemical formulas are CH<sub>4</sub>, C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>, CaCO<sub>3</sub>, NH<sub>4</sub>NO<sub>3</sub>. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 14:20, 8 February 2007 (UTC)
:CH<sub>4</sub>
:*[[Methane]]
:*5 atoms (one C atom and four H atoms)
::<math>{CH}_4 = \underbrace{C }_1 + \underbrace{H + H + H + H}_4,</math>
:C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>
:*[[Acetic acid]]
:*6 atoms
:CaCO<sub>3</sub>
:*[[Calcium carbonate]]
:*5 atoms
:NH<sub>4</sub>NO<sub>3</sub>
:*[[Ammonium nitrate]]
:*9 atoms
:− [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 14:42, 8 February 2007 (UTC)
Molecular formulas are not very specific for organic molecules, many of which can have the same composition of atoms, but different structures. For example, [[glycolaldehyde]] is also C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>. --[[User:Spoon!|Spoon!]] 21:08, 8 February 2007 (UTC)
:And methyl formate, methyl dioxirane, acetaldehyde oxide, and also a host of less stable isomers. [[User:DMacks|DMacks]] 21:27, 8 February 2007 (UTC)
== arun singh bagh ==
can I die if I lick pure diamond?
*Well, it might be sharp and cut you, but otherwise no ... it's just carbon, which isn't toxic. [[User:WilyD|WilyD]] 15:15, 8 February 2007 (UTC)
(Note I guess Arun Singh Bagh is your name - it helps if the section title relates to the question eg "Are diamonds poisonous" or something like that - most people put their name at the end of the question.)[[User:83.100.158.135|83.100.158.135]] 15:17, 8 February 2007 (UTC)
:No. Never. Well, maybe if you lick it thousands of times until your tongue becomes swollen, causing you to asphyxiate; or after the thousands of licks, if it is cut, and you get an infection. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 15:23, 8 February 2007 (UTC)
no, as in times gone by people would lick diamond to check whether or not they were genuine, a real diamond's (as opposed to a piece of glass or other rock) surface acts much like oil and does not get wet.
I bite lick and nibble on jewels all the time and none of them are poisonus. all i know is that i can tell the diffrence between a real jewel and a fake one by licking it . (yes i guess its kinda gross but hey I get and give that peace of mind when you know you got the real deal instead of the fake plastic or glass ones) [[User:Maverick423|Maverick423]] 16:05, 8 February 2007 (UTC)
:Nonsense - you will certainly die if you lick diamond. In fact you'll die anyways. We all die. (groan) --[[User:bmk|bmk]]
How do you know everyone will die, it hasn't happened yet:) Licking doamonds could make people live forever for some reason, but there is no proof:][[User:Hidden secret 7|HS7]]
:[[Diamond]]s are the hardest naturally occurring things known to science. It takes another diamond to make any impact on its surface. That means you could lick one 24/7 for 50 years and you'd still never get any of its substance into your body at all. All you'd ingest is whatever dirt happened to be on its surface. As WilyD says, swallowing one whole could be a hazard, but that's nothing to do with poison. [[User:JackofOz|JackofOz]] 02:20, 9 February 2007 (UTC)
== Does it snow at sea? ==
Many thanks, --[[User:194.176.105.40|194.176.105.40]] 15:51, 8 February 2007 (UTC)
:Yes. (but it doesn't lay obviously)[[User:83.100.158.135|83.100.158.135]] 15:54, 8 February 2007 (UTC) It would be more likely to snow nearer to the poles. Apologies I haven't provided a very good answer.[[User:83.100.158.135|83.100.158.135]] 16:11, 8 February 2007 (UTC)
:: I had the opportunity to ride the [[Alaska Marine Highway]] [http://www.stanford.edu/~nwmoussa/images/Kodiak/DSC00508.JPG] during a blizzard[http://www.stanford.edu/~nwmoussa/images/Kodiak/DSC00499.JPG] in [[November 2006]]. Indeed it does snow at sea. Other interesting phenomenon of snow-at-sea: water retains its temperature due to its high [[specific heat]], so the ocean (sound, bay, etc) may be several degrees warmer than the snowing air. This provides a consistent thermal [[updraft]] of air which starts at the surface of the water and flows upwards, [[convection|convecting]] with the snowy air. This means that it is very difficult for snowflakes to actually land on the water! In fact it appears to be snowing upwards. [[User:Nimur|Nimur]] 19:41, 8 February 2007 (UTC)
:::Cool! Now I want a video of this! — [[User:Kieff|Kieff]] | [[User_talk:Kieff|Talk]] 22:33, 8 February 2007 (UTC)
== Boric Acid ==
Hello
On your page about Boric Acid, it is mentioned that "boric acid can also be used as an acne treatment (see directions for solution at bottom.)"
I cannot find the "directions" for the solution and would like help or directions for this?
I hope someone can be of assistance.
Thanking anyone in advance.
Gavin
:I've removed that info for now as I can't find an adequate reference - however it is true that boric acid can be used as an antiseptic - the proportions were 1 part Boric acid to 4 (boiling) water to dissolve the boric acid. I can't guarantee this is correct.
If you intend to use boric acid for this purpose - I would suggest either - following any instructions on the package OR following the instructions given to you by a pharmacist (it is usually bought at a pharmacist and a pharmacist should be able to give you instructions on it's correct use.)[[User:83.100.158.135|83.100.158.135]] 16:21, 8 February 2007 (UTC)
Note also that repeated use of boric acid/borates can cause poisoning - specifically when it comes in contact with a wound eg broken skin.[[User:83.100.158.135|83.100.158.135]] 16:23, 8 February 2007 (UTC)
:It is a leftover from [http://en.wikipedia.org/w/index.php?title=Boric_acid&diff=101496284&oldid=97453653 an old edit]. Have a look at the MSDS sheet for this substance too. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 16:27, 8 February 2007 (UTC)
::...like [http://www.jtbaker.com/msds/englishhtml/b3696.htm this one], courtesy of the [http://www2.siri.org/msds/index.php SIRI MSDS index]. Or check out the [http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc09/icsc0991.htm ICSC]. Although the [http://www2.siri.org/msds/tox/f/q34/q296.html toxicology reports] may be more relevant here; the MSDS and ICSC are for the concentrated stuff, and mostly just say you should be careful when handling concentrated acids (even weak ones like H<sub>3</sub>BO<sub>3</sub>). Just for comparison, here are the corresponding [http://www.jtbaker.com/msds/englishhtml/a0326.htm MSDS], [http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc03/icsc0363.htm ICSC] and [http://www2.siri.org/msds/tox/f/q2/q853.html toxicology reports] for [[acetic acid]]. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 14:13, 9 February 2007 (UTC)
== Genetics of Neurospora ==
Hello,
When you want to calculate the distance between 2 linked genes in Neurospora Crassa, if you don't know the number of crossing-overs, when do you use the non-corrected formula (RF = 0.5*T + NPD) and when do you use the corrected one (RF = 0.5*T + 3*NPD)?
Thanks in advance!!
-- Max
== Voltage Coefficient ==
Hello... Could someone pleae precisely define Voltage Coefficient??? It is a specification mentioned in data sheets of carbon filmed resisitors... [[User:Bhavikmehta2685|Bhavikmehta2685]] 17:33, 8 February 2007 (UTC)
:This is when a change in the physical characteristics of a component are changed somewhat due to a change in the voltage across the component. See [http://www.eetkorea.com/ARTICLES/2004JUN/2004JUN21_AMD_PD_AN.PDF] − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 17:41, 8 February 2007 (UTC)
Thanks a lot [[User:Bhavikmehta2685|Bhavikmehta2685]] 05:08, 9 February 2007 (UTC)
== Current problem ==
I have a problem, I have to generate 30 Amps across a resistance of less than one milliohm. Basically, I want to find a way to convert a dc voltage to about .01 volts. I can't find a dc to dc converter that can do this. Any ideas?
Try holding one end in each hand, you might be able to produce a small amount of electricity that way:][[User:Hidden secret 7|HS7]]
:Wouldn't you know it: [[DC to DC converter]]. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-08T19:56Z</code>
The 1 milli-ohm resistance will do almost nothing to your circuit ''if you add it in [[Series and parallel circuits|series]] to an ideal [[current source]]''. You can probably create a current source which is "ideal" compared to a 1 milliohm resistance with a simple battery and resistor. I don't know if a standard lantern-battery can provide 30 amps, even at 12 volts; this is a lot of juice. But if you have a dc power supply, it should be no problem. One final question: are you ''sure'' you need to put 30 amps across 1 milliohm? This may not really be what you want, and you might smoke some components :) [[User:Nimur|Nimur]] 19:57, 8 February 2007 (UTC)
:: We used to use [http://www.megabatteries.com/item_details.asp?id=13700&cat_id=58 these types of batteries] (9.6 volt toy-racecar batteries) to drive current through some tinfoil - ''specifically for the purpose of igniting matches during science projects''. You'll quite probably do the same, if you're driving 30 amps into a short circuit. [[User:Nimur|Nimur]] 20:05, 8 February 2007 (UTC)
Perhaps I should restate everything I've said above in one sentence: your task is generating 30 Amps, then [[Kirchhoff's Current Law|attaching that into your circuit]]. The voltage will appear across your resistor - you don't need to generate it. But (in dc circuits) you can't get 30 amps unless your battery can supply it... [[User:Nimur|Nimur]] 20:13, 8 February 2007 (UTC)
what he said ^^
anyways the only other way that i can see you generating more ampage is by using [[conductors]] (the little ones that look like tiny batteries) and connect them to resistors to reduce the charge to .01 i used to do this when i made small battery powered robots so as to not fry the main processing unit but to provide enough power to the wheels and stuff.[[User:Maverick423|Maverick423]] 20:42, 8 February 2007 (UTC)
:If you explain why you need to do this we may be able to advise you better. Not knowing your age or qualifications to work with electricity, I must caution you strongly against experimenting with high current (which I consider this to be) or high voltage, on the account of the danger of shock, fire, explosion, burns, or eqiuipment damage, which can occur in an instant even if you do not accidentally hook something up wrong. A qualified teacher or a qualified adult should be present and supervise all work and assure that all proper safety procedures are followed. If you or they do not know what those procedures are, then do not attempt to do the experiment and keep as a "thought experiment." I have worked out how to do it, but will reserve details until I hear more about why and how you want to do this, and what your age and qualifications are.[[User:Edison|Edison]] 23:00, 8 February 2007 (UTC)
::Yes. Perhaps we should make it very clear that '''this much current can be very dangerous.''' Even if you are "experienced," you can burn yourself, electrocute yourself, damage your equipment, and otherwise cause harm. [[User:Nimur|Nimur]] 00:38, 9 February 2007 (UTC)
:::And despite those things, the experiment can fail to be amusing. Electricity does not make exceptions for age, inexperience, misunderstanding, or give second chances.[[User:Edison|Edison]] 00:43, 9 February 2007 (UTC)
Hello, sorry about the delay. I am trying to create a magnetohydrodynamic pump actually, and as it turns out quite a bit of current is necessary to drive the fluid medium I desire, liquid gallium. Unfortunately, the resistance across this small gap of liquid gallium (between two graphite electrodes) is extremely small. I was hoping to find a way to shrink the voltage down considerably, but most of my ideas seem to have run into issues, as I would need such an incredible rheostat to generate this many amps. I have been considering using a car battery and a self built variable resistor from carbon rods, but as you said I'd be afraid some part of the system would smoke. I am a senior student who is working on a science fair project, and I have sought out help from a few teachers and engineers. All of whom are glad to supervise me for this project.
Eep. First of all, I would avoid using a car battery. Lead-acid batteries of that size can pack enough punch to be fatal if you screw up. Next, I think you may have hit on several of the engineering issues with a magnetohydrodynamic pump already. For something as viscous as gallium, you will probably notice that mechanical and fluid forces are significantly stronger than any electromagnetic force you can produce. This is why few (probably zero) commercial pumps operate on this principal. Danger aside, I doubt you will be able to make this thing work - [[magnetohydrodynamics]] is an advanced area of physics, so you will probably have difficulty with the [[Plasma (physics)|theory]]; it also has numerous practical issues, so you will probably have difficulty with the [[Nuclear fusion|implementation]]. There are many options, though!
*You can come up with a complete report and theoretical diagrams of how you would build this device. Mention the practical engineering limitations (need high [[current]], high [[voltage]], and where in the heck will you get that much [[gallium]]! Certainly not your school's chemistry lab, I don't think it's very common in such settings! You can probably order a few ounces at exorbitant prices from science supply warehouses...[https://www1.fishersci.com/Coupon?cid=1334&gid=222432 $40 for 5 grams!]) Talk about how all of science and engineering are fundamentally dominated by practical considerations. It is not a failure to determine something is infeasible. In fact, it would be much more of a failure to pursue something that is beyond your capacity, and then [[cold fusion|not deliver it]].
*You can also try switching to some other similar experiment- such as an electric [[ion pump]]. You can use this technique to [[Dissociation (chemistry)|dissociate]] ions in solution (i.e. extract sodium and chloride from salt water). This will be an interesting chemical reaction and you can discuss a lot of the science behind it. Or you could try to build a simpler mechanical [[pump]]. You can discuss the difference between a rotary pump and an internal combustion engine. You can discuss practical uses of these pumps, and explore why [[Nothing|few applications]] rely on magnetohydrodynamic pumps.
Hope this helps, [[User:Nimur|Nimur]] 02:10, 9 February 2007 (UTC)
:MHD principles are a lot more frequently applied on micro scales, such as in MEMS (and in some theoretical applications, but that's not my area). The high magnetic field density required makes this a non trivial effort on the macro scale. I also wouldn't bother with the wikipedia article on MHD. It's poorly written, has poor topical coverage, is vague, etc. All you need for a simple MHD pump is a conductive fluid and a sufficiently large magnetic field. If you've really set your heart on an MHD pump, at least change the fluid you're attempting to flow to something that will make your construction job easier rather than harder.
:Also, I must respectfully point out to the above poster that a car battery is not likely to kill you unless you drink its contents or allow it to fall off a ladder onto your head. In addition, I think there may be some confusion as to the nature of an MHD device, since one need know nothing more than the [[Lorentz force]] equation and basic math to understand how it works. Plasma physics only apply if you're trying to manipulate a plasma, which doesn't seem to be the intention here. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-09T03:13Z</code>
::Better to err on the side of caution :) Anyway, I've only ever seen MHD applied in two areas: stellar physics, and fusion reactions. I've never to MEMS or pumps or anything else. Are you sure you don't mean [[Microfluidics]]? Those tend to make use of electric fields for moving around microdroplets of water or chemical, but I've never heard of them using magnetics. [[User:171.64.91.48|171.64.91.48]] 05:16, 9 February 2007 (UTC)
:::I meant what I said. Electrostatics are much more common, but MHD has been used as well. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-09T05:40Z</code>
::OK, To cause 30 amps to flow across .001 ohms requires that you supply a voltage of .03 volts, from E=IR. This will dissipate 0.9 watts in the .001 ohm resistance, from P=EI. A 6 volt lantern battery cannot supply this much current, nor can D cell flashlight battery. It is practically a dead short. For a test circuit, what physical form might your .001 ohm resistance take? From [[American wire gauge]], the resistance of number 10 copper wire (the smallest size usually rated to carry 30 amperes) is .9989 ohms per thousand feet, so 1.001 foot of the wire will have the desired resistance of .001 ohms. You will find that the contact resistance between the battery or other source and the wire will greatly increase this resistance. I find that the leads of my digital multimeter have about .2 ohms resistance, for example. To measure the current you may connect a voltmeter across the approximately 1 foot of number 10 wire, and then use Ohm's Law again, but in the form I=E/R. where R=.001 ohm. If you had a battery capable of producing more than 30 amps, such as a 12 volt car battery. you '''MUST NOT''' just connect the 1 foot of number 10 wire across the battery, because that would be a short circuit. It would draw far more than 30 amps (perhaps hundreds of amps) and might cause the battery to explode or the wire to heat up red hot. If the battery produces 12 volts exactly and you wanted to reduce the current to 30 amps, you must have a dropping resistor in series with your .001 ohm resistor, to drop the voltage from 12 volts to .03 volts. This works out by [[Ohm's law]] to (11.97 volts)/(30 amperes)= .399 ohms. Even if your MHD cell were shorted, with the stated dropping resistor, the current would not increase much. It is acting something like a current source. Again from the wire table article, for number 10 copper wire, this equals (1000 feet) times(.399/.9989)=399.4 feet of number 10 copper wire, or an equivalent resistor. The power dissipated in the dropping resistor will be 30 squared times the resistance or 359 watts, so such a resistor would be very hard to find, and the wire will heat up, so the current should be only briefly applied. The car battery would discharge, and the car alternator would be overloaded, if this current drain were sustained. So in the case cited, an improvised dropping resistor could be the stated amount of number 10 wire. You could measure the current with an ammeter in series, or with a voltmeter across the dropping resistor and use Ohm's law. A second way would be to use a stepdown transformer which steps down the household voltage (such as 120 or 240 depending on your ___location) to a high current at a low voltage. An electric welder has this characteristic. Some arc welders produce DC output, although it will be pulsating rather than smoothed DC. Others produce low voltage high current AC, which could be rectified with diodes to produce DC. A filter might be used to smooth the ripple, with capacitive filtering. You of course must assume all risk in such experiments. [http://www.dansworkshop.com/Homebuilt%20arc%20welder.shtml] discusses a home-made arc welder, starting with a transformer of the required KVA and replacing the original secondary with a low voltage-high amperage secondary of one or a few turns. This would also require high amperage rectifiers and capacitive filters to produce smooth DC, and would also have all the risks associated with experimenting with electricity, such as death, injury, or property damage. [[User:Edison|Edison]] 05:18, 9 February 2007 (UTC)
If I were doing this "professionally", I would do what someone suggested above: Consider operating a [[Voltage regulator|switching regulator]] as an "[[Current source|ideal current source]]". It would be pretty efficient, compact, and safe. But such parts aren't readily available to be bought "off the shelf".
So for a science fair, I'd take a different approach. I'd probably take a car battery and mount it safely in an insulating container along with five or six automotive headlamps. I'd wire the headlamps in [[Series and parallel circuits#Parallel circuits|parallel]] and connect one end of that parallel circuit securely and safely to the battery. I'd provide heavy wire leads from the other end of the battery and the other end of the headlamp circuit. Then, when you connect those external leads together, you'll get a lot of [[light]] and about 30 amps of current flowing in the circuit. The exact resistance of the external part of the circuit won't matter much because the lamps are safely limiting the flow of current. The circuit is also limited to 12 volts (the open-circuit voltage of the battery). Packaged up nicely (with no external access to the junction between the battery and the lamps), the device would be quite safe. You could add a [[circuit breaker]] as protection and to provide a convenient on/off [[switch]].
Two notes:
* [[Incandescent light bulb]]s have very low resistance when the filaments are cold, perhaps 1/10 of the resistance they have when the filaments are hot. So my proposed circuit will put out a brief pulse of much higher current. This probably doesn't matter (and might help get the gallium moving), but please be aware of that effect and consider it.
* The circuit breaker probably wouldn't be rated to break [[Direct current|DC]] and so it probably wouldn't last a huge number of operations, but it would probably be fine for "science project" duty.
[[User:Atlant|Atlant]] 13:56, 9 February 2007 (UTC)
== Purpose of a manned space flight program ...? ==
Given the fact that if you could cram 200 people onboard a space shuttle and thereby limit the number of space shuttles required to put the Earth's population into Earth orbit to 32,875,406 in the event a wayward asteroid headed this way what is the purpose of a manned space flight program besides the E-ticket ride? [[User:71.100.10.48|71.100.10.48]] 21:19, 8 February 2007 (UTC)
:I'm not sure what the question is. There are not 33 million shuttles, nor will there ever be. By the time such an event will happen, who knows how many people will live on Earth? Even if there were 33 million shuttles, that would not be enough, since you would also need to fit enough food, oxygen, and fuel, ''and'' you would have to figure out the logistics of rallying billions of people into all of the shuttles. − [[User:Twas Now|'''Twas ''Now''''']] <small>( [[User talk:Twas Now|talk]] • [[Special:Contributions/Twas Now|contribs]] • [[Special:Emailuser/Twas Now|e-mail]] )</small> 23:02, 8 February 2007 (UTC)
:The chance that if life on earth was to end the possability that it can still exist elsewhere [[User:Maverick423|Maverick423]] 22:49, 8 February 2007 (UTC)
:To quote [[Sam Seaborn]]: "‘Cause it’s next. For we came out of the cave, and we looked over the hill, and we saw fire. And we crossed the ocean, and we pioneered the West, and we took to the sky. The history of man is hung on the timeline of exploration, and this is what’s next." - [[User:Akamad|Akamad]] 23:05, 8 February 2007 (UTC)
::Or to quote [[Arthur C. Clarke]] who was quoting Konstantin Tsiolkovsky, "The earth is the cradle of humankind, but one cannot live in the cradle forever." --[[User:81.230.70.70|81.230.70.70]] 00:05, 9 February 2007 (UTC)
The purpose of the manned space flight program is because there are some tasks which are best performed by humans (as opposed to robots, computers, or anything else you might put in space). The purpose of a space program, in general, is many-fold, and includes science, politics, exploration, and many other details. I don't think it's correct to say that any present-day manned space program exists with the intent to "save our population" or "colonize other worlds." Perhaps you can take a look at NASA's Strategic Mission objectives from 2006: [http://www.nasa.gov/pdf/142303main_2006_NASA_Strategic_Plan_sm.pdf], which clearly explains exactly why we have a manned space program in the United States. (I mean, in all truth - the buck stops here. This report is what is given to federal government decision makers to explain why we have a space program, and why it should be funded). [[User:Nimur|Nimur]] 00:43, 9 February 2007 (UTC)
Here's my cynical summary (for those who don't want to read all 44 pages:)
#Kill space-shuttle program within four years
#Kill the funding for [[International Space Station]] as soon as we've met our contractual obligations
#Focus on ground-based science, which is cheaper
#Introduce a new space transportation system with no long-term commitment (per-mission funding)
#Outsource as much as possible to private contractors
#Initiate a hypothetical and entirely implausible moon exploration directive which will veil the previous objectives until the space program deteriorates beyond a salvageable enterprise.
But, this is just my opinion. You should read the report yourself. [[User:Nimur|Nimur]] 01:09, 9 February 2007 (UTC)
:The purpose of the manned space program was, originally, to prove that we had a bigger [[Penis|dick]] than the [[Soviet Union|Rooskies]]. Now, it is primarily a [[corporate welfare]] program operated to transfer American tax dollars to a small set of investors in the [[military-industrial complex]]. Nearly everything we do through manned "exploration" could be done by our robots at a much lower cost.
:[[User:Atlant|Atlant]] 14:07, 9 February 2007 (UTC)
What about in the case of nuclear war? Wouldn't a manned space flight program at least prepare Americans for orbital evacuation? That would only require 1,492,221.07 space shuttle flights at 200 Americans per trip... and who needs food? They could dine on each other. [[User:71.100.10.48|71.100.10.48]] 17:23, 9 February 2007 (UTC)
== Essential amino acid ==
I am looking for lists of [[essential amino acid]]s required by various animals. In particular, I'm interested in domesticated animals ''e.i.'' cattle, cats, chickens...
Know of any source for this information?
[[User:Ike9898|ike9898]] 21:36, 8 February 2007 (UTC)
== Rubbing Alcohol ==
what will happen if a person consumes 1 fl oz. of rubbing alcohol?
it's 70% isoproyl alcohol
:Probably a seriously upset upper GI tract, followed by some vomiting. Isopropanol is not for human consumption. See below comment. -- [[User:Matt Britt|mattb]] <code>@ 2007-02-08T22:39Z</code>
::We're not qualified to answer questions about medical problems here at the Reference Desk. You should contact your local poison control center or your physician to receive reliable, thorough answers to these types of questions. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 22:48, 8 February 2007 (UTC)
== Brain vomiting mechanism ==
A few years back I read a story in which a man died after receiving a "sherry enema", which raised his BAC to something like 0.47. (If you don't believe this, google "sherry enema".) But if one was to drink a bottle or two of wine, it's likely the brain would decide the body needs to vomit to get rid of the toxins.
The question is: When alcohol is involved, does the brain tell the body to purge the contents of the stomach because the alcohol/blood ratio is too high (regardless if the stomach is full of alcohol or not...the brain just "assumes" that's where it is), or because the alcohol simply irritates the stomach?
I.e. if someone became drunk through means other than traditional oral consumption, would they still vomit?
This may sound like a sophomoric question, but it is really a question about how the brain may be "tricked" into doing something that is, in this case, essentially useless in helping to solve the problem.
Thanks.
[[User:Darnoc|Darnoc]] 22:27, 8 February 2007 (UTC)
:This is presented as information or observation, and not as medical advice. Drinking a large quantity of wine is just as likely to cause the person to go to sleep as it is to cause them to throw up. Deaths from frat initiations often occur when the person passes out or falls asleep, and their "buddies" put them in bed to sleep it off. They never wake up. If they vomit in their sleep they may aspirate the fluid and die from the effects on the lungs. [[User:Edison|Edison]] 00:49, 9 February 2007 (UTC)
:: I don't think it's sophomoric at all! According to [[Vomit#Vomiting_center]], there are several sensory inputs to the vomit response mechanism. We would hope that the first-pass "poison sensor" is in the [[Enteric nervous system|stomach]], to induce vomiting before any has a chance to be absorbed. It does not appear that there is any "toxin" sensor there, though - only other assorted nerves. This seems in agreement with a normal situation - the vomiting does not begin immediately (sometimes it may take hours), I can only imagine that the perception of "poison" occurs after alcohol or other toxin has already entered the bloodstream. In that case, vomiting may do very little to eliminate poison (depending on how much is left in the stomach). Maybe a qualified biologist knows more about this. [[User:Nimur|Nimur]] 00:50, 9 February 2007 (UTC)
::: More speculation: my impression is that fatal alcohol intoxication is usually the result of consuming massive quantities of hard liquor. For anything with a lesser alcohol content (e.g. beer or wine), you can't physically get enough of it into your stomach to then get a fatal amount into your bloodstream.
::: (But this begs the question of where the vomit response is triggered and why it's delayed. The explanation usually given in cases of fatal alcohol intoxication is that the victim drank too much too fast for his body to protect itself from, but this does suggest that a reaction involving organs other than the stomach is involved.) —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 01:02, 9 February 2007 (UTC)
== "Lake Overturn" ==
I was searching for some information regarding most lakes' seasonal "overturn," or the event where the top layers of water mix with the bottom layers of water in a lake every spring and fall (or something like that). However, I have forgotten the name of this event. I figured it was like "Lake Overturn" or something like that, but that only redirects me to [[Limnic Eruption]]. If anyone knew the exact name of this event, could you please tell me the name, and if possible, the page? Thanks a lot!
--[[User:70.48.177.87|70.48.177.87]] 23:50, 8 February 2007 (UTC)
Sorry, I found the information after a little while. Thanks anyways though! --[[User:70.48.177.87|70.48.177.87]] 00:05, 9 February 2007 (UTC)
:Where did you find it? I am also interested. --[[User:Spoon!|Spoon!]] 01:58, 9 February 2007 (UTC)
The best term I found was 'seasonal lake turnover', as explained here: [http://www.epa.gov/glnpo/atlas/glat-ch2.html] However, this would make a great article! --[[User:Zeizmic|Zeizmic]] 02:48, 9 February 2007 (UTC)
:If this happens twice a year, the lake is ''dimictic''. If it never fully turns over (true of some deep lakes), it's [[meromictic]] (I do like that word!); if permanently frozen, ''amictic''. [http://144.16.93.203/energy/monograph1/Glossary.html Search on this page] for other "mictic" words in this family. --Anonymous, February 9, 2007, 23:16 (UTC).
== DRY ICE questions ==
Does carbon dioxide burn?
is carbon dioxide gas heavier or lighter than normal air?
thanks,
anon
:Consider reading the [[Carbon dioxide]] article, or [[Fire_extinguisher#Carbon_dioxide|the CO2 Fire Extinguisher]] section. [[User:Nimur|Nimur]] 01:15, 9 February 2007 (UTC)
:Sort of depends on your definition of "burning". See [http://jchemed.chem.wisc.edu/jcesoft/cca/cca0/MOVIES/MAGCO2.html]. [[User:DMacks|DMacks]] 01:30, 9 February 2007 (UTC)
::(Wow! Cool. Thanks. I have never heard of that reaction. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 01:39, 9 February 2007 (UTC))
:Also, if you touch dry ice to your skin for very long, you will freeze your skin and get what is usually called a burn (because it hurts just like one, and involves subcutaneous tissue damage just like one, even though it's caused by extreme cold rather than extreme heat). —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 01:38, 9 February 2007 (UTC)
:The density of [[carbon dioxide]] at 100 kPa and 0 °C is 1.6 kg/m³, where has [[air]] a density of 1.2 kg/m³ at sea level at 20 °C. So 1 m³ of carbon dioxide will be heavier than 1 m³ of air under similar conditions. But note that air contains carbon dioxide. - [[User:Akamad|Akamad]] 01:47, 9 February 2007 (UTC)
::Burning almost always means [[oxidizing]], and it's not common to oxidize a stable oxide (like CO2). [[User:Nimur|Nimur]] 02:55, 9 February 2007 (UTC)
Aw man i love dry ice every hollows eve the lunch lady would always drop a peice of dry ice in my drink and it would fog and carbinate and taste kinda like coke! you should try it once its fun and gets ya alot of attention. also i experimented with it using bubbles (i was very bored) and i noticed that the ones that didnt pop would get stuck on the ice and freeze (as a bubble) and it look really cool. i miss my youth [[User:Maverick423|Maverick423]] 14:37, 9 February 2007 (UTC)
=February 9=
== Hottest Temp... ==
Amigo of mine said that it hasnt been above 100 Farenhiet in the U.S. in February of '07, is this true? I just read a NASA article that said Death Valley, CA, USA is the hottest place on the Earth...for real?
Cheers,
[[User:72.70.4.120|72.70.4.120]] 02:02, 9 February 2007 (UTC)moe.ron
:Since it's barely a week into February, and February being in the winter, I highly doubt the U.S. has had areas reaching 100 F, which is already not too common during the summer. But yes, I believe Death Valley is the hottest place on earth. --[[User:Wirbelwind|Wirbelwind<small>ヴィルヴェルヴィント</small>]] ([[User_talk:Wirbelwind|talk]]) 02:11, 9 February 2007 (UTC)
:I always thought the [[Atacama Desert]] in Chile had the highest recorded temperature, near 130 degrees F. I should check my numbers, though... [[User:Nimur|Nimur]] 02:56, 9 February 2007 (UTC)
Google says El Azizia in Libya, hottest temp was recorded in 1922. --[[User:PDH|Peta]] 03:51, 9 February 2007 (UTC)
:The ''[[Atacama Desert]]'' in [[Chile]] is the hottest desert in the world, ''Death Valley'' is the hottest in the United States and ''El Aziza'' is where the hottest temperature was ever recorded (some say Aswan), the top spots for that are all in the Sahara somewhere. '''[<i></i>[[User:Mac Davis|<font color="#006600" face="Times"><i>Mαc Δαvιs</i></font>]]<i></i>]''' [http://en.wikipedia.org/wiki/User_talk:Mac_Davis X] <small>([[User_talk:Mac_Davis/Improvement|<font color="#666666">How's my driving?</font>]])</small> ❖ 04:33, 9 February 2007 (UTC)
:also check out [[Marble Bar]], claimed to be the hottest town. It is located in Australia. But the most extreme here is 119.8F. Its consistently hot for months at a time. [[User:Graeme Bartlett|GB]] 06:24, 9 February 2007 (UTC)
== Sound coming from tv to computer speakers ==
I've noticed that sometimes when I put my hand against my tv screen, which is right by my computer speakers, a sound comes out of my computer speakers. They aren't hooked up in any way so I was wondering how this could be. Thanks. [[User:Imaninjapirate|Imaninjapirate]]<sup>[[User talk:Imaninjapirate|talk to me]]</sup> 02:22, 9 February 2007 (UTC)
:My guess is that you get a lot of static 'sparkles' when you put your hand on a CRT screen in dry humidity. This could be picked up by the speaker wires, especially those amplifying ones, that are powered on, but not connected directly to a computer. --[[User:Zeizmic|Zeizmic]] 02:51, 9 February 2007 (UTC)
::Ah, I see, I do feel those static sparkles. Thanks for the response! [[User:Imaninjapirate|Imaninjapirate]]<sup>[[User talk:Imaninjapirate|talk to me]]</sup> 03:10, 9 February 2007 (UTC)
:::Perhaps it's [[Electronic voice phenomenon]]? :) [[User:Nimur|Nimur]] 05:30, 9 February 2007 (UTC)
== Pressure treated lumber splinter under the skin...? ==
I know that pressure treated lumber has arsenic and copper compounds, etc. to prevent insects from attacking the wood. So what happens if one gets a splinter when carrying pressure treated lumber? Is there enough toxic chemicals in a splinter if left under the skin to get into the blood stream and cause death? [[User:Barringa|-- Barringa]] 03:32, 9 February 2007 (UTC)
: Not cause death, no. If the preservatives were that toxic to humans, you wouldn't be able to buy the wood just anywhere, and you wouldn't carry it bare-handed ever, and you wouldn't build decks out of it that you would then walk on barefoot or casually eat spilled hamburgers off of.
: With that said, though, the chemicals are pretty nasty. I've noticed that if I saw pressure-treated wood, I feel a raspy sensation in my throat that I certainly don't get when sawing regular wood. (Yes, I should probably wear a dust mask more often.)
: I don't think I've heard of splinters from treated wood being hazardous. (If anything the chemicals might help kill the germs that might otherwise infect the puncture wound.) But I'd certainly pay extra attention to a nasty puncture from treated lumber, and seek medical attention if my skin turned a funny color or anything. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 03:49, 9 February 2007 (UTC)
==[[Electronic voice phenomenon]]==
Hello, I think I have stumbled upon an absurd situation at this article. I have tried to place a tag alerting editors that content policies may not be followed there. There is original research, and non-objectivity. For example, the article divides points of view into "paranormal" and "non-paranormal." The scientific point of view is referred to as "non-paranormal," rather than scientific. Also, scientists are referred to as "skeptics," rather than scientists, as if believing in extraterrestrials communicating via magnetic tape were the majority viewpoint, and there were some minority "skeptics." I believe it is the other way around, there is a minority which believes in this, and the scientific majority does not. Scientists are scientists, not skeptics and non-paranormals. Also, the article contains a self-published purported recording of a paranormal voice, which is original research, I believe, since it was recorded and published on a website by the same people, not by a reliable third party. an editor keeps removing the tag I have placed. I am not sure what to do.-[[User:MsHyde|MsHyde]] 05:12, 9 February 2007 (UTC)
:Yikes. At least posting it here will get more eyes on it, and hopefully that will help build a majority consensus. [[User:Nimur|Nimur]] 05:19, 9 February 2007 (UTC)
::I've read through the article. They make very few [[falsifiable]] claims, so I don't know if you can truly cite them on inaccuracy (though it's certainly not a science article). I guess it's difficult to accept, but people will believe what they wish to believe. In its present form, the article clearly states that there are alternative, simpler explanations than the "supernatural" - but if people choose to conclude otherwise, no amount of proof can convince them. [[User:Nimur|Nimur]] 05:28, 9 February 2007 (UTC)
:It's fascinating how one paranormal wiki-page can lead me onto a goose chase of paranormal stuff. If EVP infuriates you, check out [[Shadow people]] - there's all KINDS of awful science there! Anyway, it looks like there's some consistency among these pages. They all list Paranormal vs. Non-Paranormal explanations. Honestly, I'm content with that level of consistency. Though you and I may choose to believe the scientific explanation, assume good faith and let people think what they will. It doesn't harm us to allow them to live in ignorance. Plus it makes for entertaining television. [[User:Nimur|Nimur]] 05:33, 9 February 2007 (UTC)
::Yes, but this is an encyclopedia. Neutrality is important. The original research policy looks like it was developed precisely to keep crackpot theories in check. That is fine if people want to privately believe that science is "non paranormal," but it is not appropriate to label it that. The majority definition of science is science, not "non paranormal." And the audio recording is, frankly, ridiculous. It was published on a website by the same people who recorded it. It could be a recording of their vacuum cleaner.-[[User:MsHyde|MsHyde]] 06:33, 9 February 2007 (UTC)
:::The original research policy also keeps you from using your own beliefs to determine the validity of an article. However bunk EVP may be, it is notable. The article, in its current state, makes no claims as to its validity, and nothing about the article is the least bit against Wikipedia's policies. Furthermore, just to cover the complaints, skeptics is a perfectly appropriate term. By definition, those who do not believe in something are skeptical of it. Finally, the audio recording is also fine. Regardless of how valid it may be, it is still an example of EVP. – [[User:Someguy0830|Someguy0830]] ([[User talk:Someguy0830|T]] | [[Special:Contributions/Someguy0830|C]]) 06:41, 9 February 2007 (UTC)
::::It is claimed to be an example of EVP, but not by a reliable source. It is the original research of two people who make money off of EVP, and self-published it on their website. Skeptics is not the appropraite term for scientists. Per due weight, even in an article about something, an extreme minority view should be represented as such. That means, science is the majority view, not the "skeptical" view, or "non-paranormal" view. The article as written is heavily slanted towards the view that EVP exists.-[[User:MsHyde|MsHyde]] 08:38, 9 February 2007 (UTC)
:::::It is not. The thing is a blow by blow history and a possible causes section, with equal weight given to both. The article does not exist to disprove or prove EVP. It only exists to detail the phenomenon. – [[User:Someguy0830|Someguy0830]] ([[User talk:Someguy0830|T]] | [[Special:Contributions/Someguy0830|C]]) 09:08, 9 February 2007 (UTC)
::: I haven't read the [[Electronic voice phenomenon|EVP]] article (if for no other reason than that I don't have time this morning for "wild goose chase of paranormal stuff", as [[User:Nimur|Nimur]] so nicely put it), but I'm prepared to believe that the article needs work. Thanks, [[User:MsHyde|MsHyde]], for trying to do something about it. With that said, this Reference Desk probably isn't the best place to figure out how to better apply Wikipedia's NPOV policy to that article -- I'd also try its [[Talk:Electronic voice phenomenon|talk page]] and the [[WP:VP|Village Pump]]. —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 13:24, 9 February 2007 (UTC)
::::Any unpublished recording is definitely original research, and should not be considered as a source to support the claimed EVP. I could make a tape with mysterious voices on it very easily. To be used in an article, it would need to be published by a "reliaable source," and in a scientific dispute it should have been published in a respected peer reviewed journal. Questionable evidence should not be used to create a Wikipedia article which can then be cited as "proof" that the claims are valid. No home-made flying saucer photos, no personal diaries of time travel or UFO abduction, no claims that one had a dream forecasting some publicized disaster. No claims that one is Elvis's love child. No personal bigfoot sitings. No claims of having invented a miracle cancer cure or perpetual motion machine. [[User:Edison|Edison]] 15:59, 9 February 2007 (UTC)
== immune system ==
Hello, i was just wondering when "B cells" inside our body is trying to fight off "invader cells" and there are also body cells there aswell how the the "B cell" tell teh difference beetween teh two other cells?
thankyou very much, i really apreciate it :D. [[User:24.68.136.43|24.68.136.43]] 05:50, 9 February 2007 (UTC)
: Our articles on [[Adaptive immune system]] and [[B cell]] answers your question. [[User:Rockpocket|<font color="green">Rockpock</font>]]<font color="black">e</font>[[User_talk:Rockpocket|<font color="green">t</font>]] 06:46, 9 February 2007 (UTC)
::I agree with Rockpocket that the articles linked to answer your question. However, they contain a lot of information if you know little about this beforehand, so here's a simplified version:
::In most circumstances, it isn't the B-cells that tell the difference between self and non-self. It's the [[helper T cells]]. Both B and T cells have antigen-specific receptors that are [[VDJ recombination|generated randomly]] by somatic DNA recombination when the cells develop. One clone of T or B cells has one receptor, which recognizes [[epitope|one single antigen]] only. B cell receptors (≈[[immunoglobulin]]) can arise that recognize just about anything. [[T cell receptor|T cell receptors]], however, are designed to recognize [[Major histocompatibility complex|major histocompatibility complex (MHC)]] molecules, which are cell surface molecules found on most cells of the body, and which always have a short [[peptide]] bound. The peptide is put there when the MHC molecule is assembled, before it goes to the cell membrane, and may be derived from either the degradation of one of the cell's own proteins, or from a virus, or from bacterial proteins that the cell has [[phagocytosis|"eaten"]]. Because of the random process that creates the receptors, auto-reactive receptors are generated both for T and B cells. Auto-reactive T cells, however, are eliminated in the [[thymus]], and never reach maturity. The T cells that reach maturity are those that recognize your own MHC molecules, with a foreign peptide in them. Those B cells that happen to be reactive towards the same foreign protein as a given [[helper T cell]] clone, will have MHC molecules that are loaded with peptides derived from that foreign protein, because recycling of their B cell receptors ensures that some of the material is internalized, degraded, and displayed on their surface bound to MHC molecules. When a helper T cell encounters a B cell with the right combination of MHC molecules and peptides, it signals to the B cell that now is the time to launch an attack against the invader. --[[User:NorwegianBlue|NorwegianBlue]]<sup>[[User_talk:NorwegianBlue| <u>talk</u>]]</sup> 13:43, 9 February 2007 (UTC)
== eutrophication ==
how can a eutrophied lake be rescued
{{unsigned|Bates g}}
{{refq|eutrophication}}--[[User:Shantavira|Shantavira]] 13:02, 9 February 2007 (UTC)
== Heat Sink Formulae ==
Given the fin surface temperature of 68 degree Celsius and resistor temperature of 100 degree Celsius what would be the heat sink design?? This is in context of a convection cooled RF Load of 60W operating at 1 GHz frequency. What would be the fin height, no. of fins and cross sectional area of fin??? The base of the heat sink is at a temperature of 87 degree celsius?
: Are you the same person who was [[#Fin Dimensions|asking this before]]? I suspect you're not going to get the precise, detailed answer you need here. You might want to try asking your instructor, or hiring a knowledgeable consultant, depending on the context of your problem. Good luck! —[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 13:28, 9 February 2007 (UTC)
::Among other factors you'll need to consider: What [[fluid]] is the heat sink immersed in, at what temperature does the fluid enter the system, is the fluid freely convecting or being forced to flow, how much [[turbulence]] occurs at the heat sink fins/pins, etc.
::[[User:Atlant|Atlant]] 14:14, 9 February 2007 (UTC)
:::Before didn't you say 600 watts? It would take a while to heat up say a gallon of oil or silicone fluid with 60 watts of heat. Engineers who miss decimal points tend to design things which do not function up to expectation. I seriously mean this. The bridge falls down or the plane crashes. I had a professor who would take half off an answer for an "oops error' on that ground. Again, seriously consider a cooling fan, and look at a space heater as a model. You must consider the ambient temperature and the air flow. Perhaps a fan could blow room air in at the bottom, so the fan is spared the heat, and the hot air come out at the top or side. You need to spare your cable and connectors from the heat. I still suggest a thermometer or thermocouple (with a design which will not be affected by the RF emission) to make sure the oil is not too hot, and a design which makes sure the resistor is not partially out of the oil. Transformers sometimes have a float switch inside ot a level indictor with a float, or in the old days, a sight glass like on a big coffee pot. You must also allow for the expansion of the oil, so you do not have a pressure buildup which ruptures the can. Detailed design goes beyoond what I or most people here have attempted. There are probably specialized programs to be used with graphical mathematical analysis programs for such heat flow calculations. Good luck. [[User:Edison|Edison]] 15:50, 9 February 2007 (UTC)
== Uranium refinement ==
According to the [[Uranium]] article, the production of uranium metal from uranium ore involves using uranium halides. Are there any simple ( but not necessary quick or efficient ) ways to produce uranium metal direct from ore ( such as using [[electrolysis]] or [[reducing agents]] ? [[User:Robmods|Robmods]] 11:17, 9 February 2007 (UTC)
== How many protons, neutrons and electrons is in the average in human body ==
Hallo, I´d need to know, how many protons, neutrons and electrons is on the average in human body? How many is it for one cell? Thank you
:You can make a rough estimate from four assumptions.
:#Essentially all of the mass in your body comes from [[proton]]s and [[neutron]]s ([[electron]]s are so light that their contribution is negligible for now; the masses of each particle are in the linked articles).
:#Your body will contain roughly equal numbers of protons and neutrons, as the most common elements and isotopes ([[oxygen]]-16 and [[carbon]]-12) in your body contain equal numbers of protons and neutrons. (For bonus points you can account for the contribution due to hydrogen, which mostly contains one proton and no neutrons; these tables have the relative contributions of each element to the body's weight: [http://web2.airmail.net/uthman/elements_of_body.html], [http://fig.cox.miami.edu/~cmallery/150/life/elements.htm]).
:#The number of electrons is equal to the number of protons—your body has no net charge.
:#Finally, the human body contains roughly 100 trillion cells: see [[Cell (biology)]].
:That should get you started. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 16:25, 9 February 2007 (UTC)
::Don't even need to know how many cells...just how much total mass. [[User:DMacks|DMacks]] 19:09, 9 February 2007 (UTC)
:::He also wants to know how many are in a single cell... --[[User:NeilTarrant|Neo]] 19:13, 9 February 2007 (UTC)
::::Ah yeah. [[User:DMacks|DMacks]], Friday-afternoon moron.
So that would be slightly more than 8x10^26 of each per kg:)[[User:Hidden secret 7|Hidden secret 7]] 19:48, 9 February 2007 (UTC)
So how many atoms is that:][[User:Hidden secret 7|HS7]]
== Fundamental Tissues ==
I am aware that there are the four primary tissues- neural, connective, epithelial and muscle- and that most(all?) tissues fall under these, but where would specific tissues of the organ fit, say liver or kidney...
:It depends. Most organs contain a mix of the four 'classical' tissue types. Taking the [[heart]] as an example, it contains:
:*'''Neural tissue''': The heart is innervated by (among others) the [[vagus nerve]].
:*'''Connective tissue''': The heart circulates [[blood]], the [[pericardium|pericardial sac]] is lubricated by [[adipose tissue]]. The fibrous pericardium and [[epicardium]] are both mostly connective tissue.
:*'''Epithelial tissue''': The [[endothelium|endothelial]] cells which line the blood vessels of the heart are epithelial tissue.
:*'''Muscle''': The heart is mostly muscle.
:In other words, you have to look at the organ in detail. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 16:37, 9 February 2007 (UTC)
::What about say specific cells like hepatocytes, kupffer cells etc. Do they have to fit into the 'primary' tissue classification? (cells do make up the tissue after all- they only seem to fit into the connective tissue group...)
:In the histological schematic you are talking about, hepatocytes are endothelial, they form sheets with clear lumina (is that the plural for lumen?); and kupffer cells are connective tissue (they are really just special macrophages). Remember that connective tissue falls into two categories, mobile (like plasma cells, mast cells etc.) and resident (fibroblasts, adipocytes, etc.). As stated above, these cell types interact metabolically and structurally to make the tissues we call organs. I can't personally think of any epithelial cells which appear without nearby connective tissue, nor muscle which occurs without neural tissue either connected (as with skeletal muscle) or somewhat nearby (though with the muscular conduction in the heart, cardiac tissue is something of an exception).<sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .1em .1em .9em .1em;">tucker</font>]]</sup>[[User talk:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .35em .1em .35em .1em;">/</font>]]<sub>[[User:tuckerekcut|<font style="color: #ffffff; background: #2f4f4f; font-family: sans-serif; padding: .9em .1em .1em .1em;">rekcut</font>]]</sub> 22:51, 9 February 2007 (UTC)
== Goldfish floating upside down ==
Ever since I got a couple of goldfish (the typical big-eyed kind that you can get in any pet store), one of them has spent a lot of time floating upside down at the top of the water. The first time I saw it do it, I thought it was dead. But a few minutes later it was swimming around fine. I've had it now for about six months and nearly every day it does this playing-dead upside down thing. Sometimes it even swims around the tank upside down for several minutes. Is this unusual behavior? Is my fish sick? Or is it just a weird fish? [[User:Deli nk|Deli nk]] 15:31, 9 February 2007 (UTC)
:Try googling swim bladder problems in goldfish. Apparently fancy goldfish are prone to problems like that. [[User:Guettarda|Guettarda]] 16:13, 9 February 2007 (UTC)
::FYI, you probably have [[Comet (goldfish)|comets]]; they're a very common kind of "fish store" goldfish. And yes, it's quite uncommon for a healthy fish to be completely inverted, although they certainly do momentary headstands, tailstands, and the like when feeding.
::[[User:Atlant|Atlant]] 17:05, 9 February 2007 (UTC)
quick question about the comet gold fish
whats the max temprature range they can survive in [[User:Maverick423|Maverick423]] 18:44, 9 February 2007 (UTC)
There seems to be quite a bit of info out there on swim bladder problems, as Guettarda suggested. After reading a bit, it's pretty clear that's the problem. Thanks all! [[User:Deli nk|Deli nk]] 19:16, 9 February 2007 (UTC)
== how much force does it take to propel a body the size of one of mars's moons or even earths moon ==
how much force to propel an object of this size???...or to change its current direction of motion??? and could humans ever achieve such a thing as propelling such large objects...??? how much does it take to fight the suns gravity and drive such a large object out of the solar system???...can the gravity of other planets be used to make it easier?? yet what would the initial force have to be like???...perhaps its easier to work with objects out near pluto???...could pluto and another object out that way be set into orbit around eachother on course heading out of the solar system???...(from a biologist)(its been a while since college physics class someone else can answer this quickly)...[[User:Benjiwolf|Benjiwolf]] 19:10, 9 February 2007 (UTC)
F=ma, therefore the force needed to move an object would be the mass of the object, (in kg) multiplied by its acceleration, which is the same as the combined forces of gravity acting on it (in m/s^2):) Gravity varies with the square of distance from an object, so away from a planets surface, most of it would come from the sun:) Therefore it would decrese as you got further from the sun, but the masses and therefore gravities of other planets also needs to be considered:( So to find the forse you would have to work out the effect of gravity, and its direction, and then use this to find the force pulling the moon &c away from where you want it to go, and then multiply this by its mass:)[[User:Hidden secret 7|Hidden secret 7]] 19:45, 9 February 2007 (UTC)
== Keeping raccoons alive ==
For my project at uni, we have to argue why we should keep raccoons alive as we are to debate with a group that says that they should be made extinct etc. Any help people?
:You could start with the general arguments on why [[extinction]] of any species is bad. Then you explain what happened when the [[wolf]] was hunted to extinction in many parts of the world, and why it is being reintroduced. --[[User:Zeizmic|Zeizmic]] 20:56, 9 February 2007 (UTC)
::I'm not sure if this would be what the moderator of the debate or whatever wanted, but costs versus benefits always works well; if you can show that it would be a lot cheaper to, for instance, buy everyone garbage cans secure against Racoon attack, than to exterminate them, then that is surely a point in your favour. --[[User:NeilTarrant|Neo]] 21:04, 9 February 2007 (UTC)
:::More importantly: If you decide to keep them alive, but change your mind next year, you could deal with them then. But if you exterminate them now, and ever change your mind in the future, there would be no way to ever get a single living raccoon back. Extinction is forever. --[[User:mglg|mglg]]<sub>([[User talk:mglg|talk]])</sub> 21:34, 9 February 2007 (UTC)
== Some Biology Questions ==
#Of the three types of RNA, which is the primary transcript of eukaryotic genes?
#An image of a mitochondria is presented, and the question is what does it have in common with chloroplasts, the choices being DNA is present, ATP is produced, and Ribosome presence, or A and B, or all three?
#A nucleotide may contain: Ribosomes, Nucleic Acid molecules, AMP, ADP, ATP?
:Any ideas as to the above, I disagree with the answer key on the above. [[User:ST47|ST47]]<small>[[User talk:ST47|Talk]]</small> 20:28, 9 February 2007 (UTC)
::How about telling us what you think the answer is and why so someone can see how/if your logic is wrong. Just being told the answer is no way to get an education... [[User:DMacks|DMacks]] 21:34, 9 February 2007 (UTC)
:::OK. #1 my response was mRNA, assuming that since they are limited-use, they would need transcription more often than re-usable ribosomal subunits and tRNA. The given answer was rRNA. #2, I knew both produced ATP, and I know both have their own DNA, I do not think either have ribosomes, so my answer was D: A and B. The Key said A, B, and C. #3, I put Nucleic Acid molecules, which is just plain wrong, but nucleotides don't contain any of those - AMP IS the Adenine nucleotide of RNA, so I suppose that was the reasoning, as that was the given answer on the key. [[User:ST47|ST47]]<small>[[User talk:ST47|Talk]]</small> 21:56, 9 February 2007 (UTC)
::::1: see our articles on [[mRNA]], [[tRNA]], and [[rRNA]]. Yeah, seems like mRNA would be a reasonable answer assuming we're talking about nuclear genes. 2: visit the "structure" section of our pages about [[mitochondria]] and [[chloroplast]]s. That third question is pretty confusingly worded indeed. [[User:DMacks|DMacks]] 23:04, 9 February 2007 (UTC)
== [[Flame test]] ==
In the [[flame test]] why do you see different colours from different salts? How is this colour made? Thanks for your help! --[[User:Flying Canuck|Flying Canuck]] 21:49, 9 February 2007 (UTC)
: Well, um, as our [[flame test]] article explains, this is due to "an [[Chemical element|element's]] characteristic [[emission spectrum]]." And as our [[emission spectrum]] explains, the colors are based on "the [[frequency]] of the light <nowiki>[</nowiki>[[electromagnetic radiation]]] the element [[light emission|emits]] when it is [[heat]]ed". Were you looking for more than that? --[[User:Ummit|Steve Summit]] ([[User talk:Ummit|talk]]) 22:38, 9 February 2007 (UTC)
== Why is that....? ==
1) When you take out earrings it feels like there's a little ball inside your earlobe?
2) What is the function of yawning and stretching - and why is it catchy?
3) What actually happens when you have 'pins and needles' or your leg is 'asleep'?
Thanking you,
San 23:18, 9 February 2007 (UTC)23:18, 9 February 2007 (UTC)23:18, 9 February 2007 (UTC)23:18, 9 February 2007 (UTC)23:18, 9 February 2007 (UTC)~
== Stop [[Global Warming]] ! ==
Why hasn't more attention been given to simply shielding the earth from sunlight? A series of thin, mirrored panels between the earth and sun would be more effective than trying to clear [[greenhouse gases]] from the atmosphere.
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