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=December 1=
==Natural fuel resources==
Which countries have natural fuel resources?
*Depends, what kind of fuel are you looking for. Almost all countries have some resources. - [[User:131.211.210.14|131.211.210.14]] 13:54, 1 December 2005 (UTC)
*Countries generally contain [[Homo sapiens|people]], which as [[Animalia|animals]] are natural. People contain carbon and thus could be used as fuel; [[Burned_at_the_stake|humans are widely acknowledged to be flammable]]. Hope this helps. --[[User:YixilTesiphon|YixilTesiphon]] 06:25, 2 December 2005 (UTC)
::I suppose pretty much all countries will have some coal, gas or oil. Whether that is commercially interresting and actually exploited is a different matter. You might look at [[opec]], [[List of oil fields]] and [[List of natural gas fields]]. [[User:DirkvdM|DirkvdM]] 10:36, 2 December 2005 (UTC)
::Also several countries have big [[biofuel]] resources (ie big forests). [[User:TERdON|TERdON]] 03:32, 6 December 2005 (UTC)
= August 17 =
== Nuclear fusion in the sun ==
[[Image:FusionintheSun.png|thumb|right]]
I've known for a long time that in the sun four hydrogen atoms fuse to make a helium atom. I never really thought about it much, but just recently I realized that four protons fusing together should make beryllium, not helium. I read some of the article [[Nuclear fusion]] and it had a pretty cool pic...[[:Image:FusionintheSun.png]], but I didn't understand most of it. Also, the pic shows the creation of a positron. What in the heck is a positron? (Supposedly the anti-matter of an electron, whatever that means) Lol! Again, over my head. Anyway, I was just wondering. Thanks to everyone in advance!
[[User:Dimblethum|Dimblethum]] 03:14, 1 December 2005 (UTC)Dimblethum
:I'm not a physicist, but the figure seems to indicate that you can produce a neutron by releasing [[positron]] from a proton. A positron is the antiparticle of an electron. --[[User:JWSchmidt|JWSchmidt]] 03:35, 1 December 2005 (UTC)
:: That's also right, there's also a [[neutrino]] involved, but they're pretty damn hard to see. There are two [[weak force|weak decays]] that affect nuclei, and they are:
:::<math>p \to n + e^+ + \nu</math>
:::<math>n \to p + e^- + \overline{\nu}</math>
:: Where p is a [[proton]], n is a [[neutron]], e<sup>+</sup> is a [[positron]], e<sup>-</sup> is an electron, and ν indicates a [[neutrino]] (or an [[antineutrino]] if there's a bar over it). Hope that helps; if you have more questions, ask them. -- [[User:SCZenz|SCZenz]] 03:51, 1 December 2005 (UTC)
== flocking and threshold ==
:::You're correct that four protons in a nucleus would make beryllium; however it is more complicated than that; a nucleus with four protons and no neutrons would be highly unstable. The reactions are detailed in [[proton-proton chain reaction]] and are too complex for me to fully explain here, but I'll try summarize. The key is the initial proton-proton reaction. Two protons come together, and one proton is converted into a neutron (an [[up quark]] transforms into a [[down quark]] I believe). In the process, a [[positron]] is emitted, which as JWSchmidt indicates is the [[antiparticle]] of an electron (see that article, or [[antimatter]] if you are not familiar with the concept—basically each particle has a corresponding antiparticle with opposite charge, spin, etc.; when a particle and antiparticle collide, they annihilate each other and produce energy via ''E''=''mc''<sup>2</sup>. This, for instance, is the basis of the matter-antimatter reactor that powers the ''Enterprise'' in Star Trek and in other science fiction. Antiparticles are normally simply named by adding ''anti-'' to the particle name; [[positron]]s are a historical exception). Also emitted is an electron neutrino. The positron will quickly meet an electron and mutually annhiliate. The rest is covered in [[proton-proton chain reaction]]; if there are specific questions you have or concepts you don't understand, ask them here. — [[User:Knowledge Seeker|Knowledge Seeker]] [[User talk:Knowledge Seeker|দ]] 03:47, 1 December 2005 (UTC)
[[Boids]] provokes a question:
:One final suggestion. If you don't understand what a [[positron]] is still, reading the [[antimatter]] article will hopefully help. -- [[User:SCZenz|SCZenz]] 03:59, 1 December 2005 (UTC)
Each boid adjusts its position and velocity to those of (I guess) its N nearest neighbors; and/or those within a distance R. Does varying N or R make the behavior resemble that of different real bird species? [[User:Tamfang|—Tamfang]] ([[User talk:Tamfang|talk]]) 03:04, 17 August 2025 (UTC)
::::All stable nuclei have a ratio of protons to neutrons that falls within a certain range (see [[Isotope table (divided)]]). If there are too many protons, some can turn into neutrons by [[beta decay]], and vice versa. A proton can change into a neutron by emitting a positron (beta plus), and a neutron can change into a proton by emitting an electron (beta minus). —[[User:Keenan Pepper|Keenan Pepper]] 03:59, 1 December 2005 (UTC)
:With the AI's assistance, I found this article [https://pmc.ncbi.nlm.nih.gov/articles/PMC3324025/ Statistical Mechanics for Natural Flocks of Birds] that states, based on field data, "...interactions are ruled by topological rather than metric distance." Boid models must account for these and other factors. [[User:Modocc|Modocc]] ([[User talk:Modocc|talk]]) 19:12, 17 August 2025 (UTC)
== Electrotheremin construction ==
::This is a great paper, do you have any more like it? [[User:Gongula Spring|Gongula Spring]] ([[User talk:Gongula Spring|talk]]) 18:03, 26 August 2025 (UTC)
:::No, I do not. [[User:Modocc|Modocc]] ([[User talk:Modocc|talk]]) 20:45, 26 August 2025 (UTC)
:The Introduction section of the paper describing the boid model<sup>[https://dl.acm.org/doi/10.1145/37401.37406]</sup> contains this passage:
I'm looking to build an [[electrotheremin]], which as I understand it is just an audio oscillator with a slide potentiometer determining pitch. However, I don't really have experience with electronics, so I can't just "wing it." Is there a place on the internet or something where I could find the schematic for such an oscillator? Or, is there a simple step for replacing a resistor in an existing oscillator circuit with the slide potentiometer? Thanks in advance. --[[User:ParkerHiggins|ParkerHiggins]] 03:17, 1 December 2005 (UTC)
::"The success and validity of these simulations is difficult to measure objectively. They do seem to agree well with certain criteria and some statistical properties of natural flocks and schools which have been reported by the zoological and behavioral sciences. Perhaps more significantly, many people who view these animated flocks immediately recognize them as a representation of a natural flock, and find them similarly delightful to watch."
:In the Conclusion section, the author writes:
::"The animations showing simulated flocks built from this model seem to correspond to the observer's intuitive notion of what constitutes 'flock-like motion.' However it is difficult to objectively measure how valid these simulations are."
:Furthermore, in the description of the model, we read:
::"The flock model presented here is actually a better model of a school or a herd than a flock [of birds]."
:In particular, it appears that natural birds look further ahead than artificial boids, perceiving the approach of a 'manoeuvre wave' and anticipating its arrival.<sup>[https://www.nature.com/articles/309344a0]</sup> So there is no claim, express or implied, that this is a valid model for flocking behaviour, but merely that it looks convincingly similar. It is not a scientific article about animal behaviour but a technological article about a difficult aspect of [[Computer-generated imagery|CGI]].
:While there have been a few studies on the properties of actual biological flocks, these seem to have been with respect, each time, to a single species, reporting the observations in a non-standardized way that makes comparisons of different species almost impossible. How well turning the N and R knobs make the boid-model simulation resemble the natural flocking behaviour of different flocking bird species will depend on the subjective judgement of observers familiar with these specific behaviours. ​‑‑[[User talk:Lambiam#top|Lambiam]] 09:47, 18 August 2025 (UTC)
Thanks both! [[User:Tamfang|—Tamfang]] ([[User talk:Tamfang|talk]]) 23:43, 21 August 2025 (UTC)
:Yes, if you already have an oscillator circuit you could replace the resistor with a slide potentiometer. Or even simpler, you could just add the potentiometer in parallel with the resistor, which wouldn't require breaking the original circuit. —[[User:Keenan Pepper|Keenan Pepper]] 15:24, 1 December 2005 (UTC)
== InsulinAugust Structure19 ==
== Is the speed of light constant, when measured by a '''remote inertial''' observer, who '''non-locally''' measures a photon traveling a long way in a '''curved''' vacuum? ==
Hi. Im doing a school project for my grade 12 biology class and I need to make a physical insulin structure. Within my sructure, needs to be the appropriate sequence of amino acids to form an insulin protein. So far, the types of insulin structures I've found on the web consist of the "leader chain, A-chain, B-chain, and C-chain". These descriptions are not what Im looking for. I need to know the exact sequence of amino acids in these chains that make up insulin.
Thank-you very much for your help.:)
I'm asking, because our article [[speed of light]] states confusingly: {{tq|'''"In non-inertial frames of reference (gravitationally curved spacetime or accelerated reference frames)'''...the speed of light can differ from c when measured from a remote frame of reference".}} This sentence seems to ignore the situation I'm asking about, when the remote observer's frame of reference is '''inertial''', but the spacetime the light travels through is '''curved'''. [[User:HOTmag|HOTmag]] ([[User talk:HOTmag|talk]]) 08:32, 19 August 2025 (UTC)
:See [http://www.petdiabetes.org/insulin_sequence.htm this page]. The structure shown is cow insulin; if you want to make a model of human insulin be sure to make the substitutions shown at the top of the page. You also have to decide on what form of insulin you are modelling: the kind that is found in the circulation (insulin proper, which is shown there) or the one which is transcribed from the RNA and processed to become that form (proinsulin). The leader-chain and C-peptide won't be found in the circulating form. (BTW, searching for "insulin amino acid sequence" would find this for you). - [[User:Nunh-huh|Nunh-huh]] 03:54, 1 December 2005 (UTC)
:The length traveled by a photo should be the path length as measured along its curved trajectory, a geodesic of the manifold that is spacetime. I am not sure how you propose the stationary observer is going to measure this. It is in fact not even clear how to ''define'' the path length (in the mathematical model of [[curved spacetime]], a [[Lorentzian manifold]]) with respect to a ''given'', fixed frame of reference. [[Inertial frames of reference]] are useful in special relativity, when objects not acted upon by a force travel in straight lines. Space curvature means that there are no "straight lines", so the inertial model for establishing a reference frame breaks down. ​‑‑[[User talk:Lambiam#top|Lambiam]] 14:07, 19 August 2025 (UTC)
::More resources: [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.box.115 A B C chains] <-- nice diagram, the three letter codes (and single letter codes) for all the amino acids are at [[amino acid]]. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Search&db=books&doptcmdl=GenBookHL&term=Insulin+AND+hmg%5Bbook%5D+AND+226046%5Buid%5D&rid=hmg.figgrp.50 This figure] shows a diagram of the entire 110 amino acids, including the leader segment. The entire 110 amino acids (single letter code) are listed here: [http://www.ncbi.nlm.nih.gov/projects/CCDS/CcdsBrowse.cgi?REQUEST=GENEID&DATA=3630 Translation (110 aa)]. --[[User:JWSchmidt|JWSchmidt]] 04:38, 1 December 2005 (UTC)
::Let's assume we (as inertial observers) see a photon travel near the sun in a curved trajectory. Do you claim we can't use any tool (e.g. a telescope or whatever) for measuring the length of this photon's curved trajectory? [[User:HOTmag|HOTmag]] ([[User talk:HOTmag|talk]]) 15:59, 19 August 2025 (UTC)
:::We can detect only photons that arrive at our ___location. If a remote photon interacts with something else in such a way as to cause emission of another photon in our direction, we can detect the resulting photon but we're not directly observing the trajectory of the initial one.
:::Saying "what if as remote observers we see a photon travel near the sun" is like saying "what if as fans watching a soccer match from 10 miles away, we get hit by the ball on its way from the players foot to the goal". A remote observer can't observe a photon's trajectory. -- [[User:Avocado|Avocado]] ([[User talk:Avocado|talk]]) 17:49, 19 August 2025 (UTC)
::::So what does the quote (from Wikipedia) in my original post mean, about when c is "measured from a remote frame of reference"? Doesn't the measurement of c made by a remote observer, mean measuring the ratio between, the photon's trajectory measured by that remote observer, and the time it takes the photon to travel this trajectory - when this time is measured by that remote observer? [[User:HOTmag|HOTmag]] ([[User talk:HOTmag|talk]]) 18:29, 19 August 2025 (UTC)
:::::I'm not a physicist nor the person who wrote the article. I would assume that we can know the time of the photon's origin based on whatever caused it to be emitted also having other effects (gravitational waves, other photons, etc) that reach us directly. And that we can measure the time of the photon's arrival at another point based on the effects of its arrival (reflected or re-emitted light, for instance) that reach us directly. And that we can thus measure the time elapsed between departure and arrival and deduce its speed. But we can't observe its trajectory, only infer it. -- [[User:Avocado|Avocado]] ([[User talk:Avocado|talk]]) 20:15, 19 August 2025 (UTC)
::::::Please note that the condition of "local measurement" (as opposed to "non-local" one) is a well known requirement for the speed of light to be constant. I've asked whether the requirement of locallity of measurement is also needed when the observer's frame of referenece is inertial. [[User:HOTmag|HOTmag]] ([[User talk:HOTmag|talk]]) 06:47, 20 August 2025 (UTC)
:You can imagine that you have a torch in your hand and point it towards a remote black hole. The light from the torch will travel in the direction of the event horizons but will never cross it (from the point of view of an external inertial observer). This effectively means that the speed of light becomes zero in the vicinity of the horizon. However the proper speed of light will remain ''c'' of course. [[User:Ruslik0|Ruslik]]_[[User Talk:Ruslik0|<span style="color:red">Zero</span>]] 20:33, 19 August 2025 (UTC)
::When a photon is approaching a black hole, both the distance traveled by the photon, and the time it takes the photon to travel that distance, approach infinity (from the inertial observer's viewpoint), so the "effective" velocity becomes meaningless rather than "zero". [[User:HOTmag|HOTmag]] ([[User talk:HOTmag|talk]]) 06:47, 20 August 2025 (UTC)
:::Sorry, but the distance cannot become infinite because it is a known quantity. Indeed, you can measure the distance to the black hole and its mass and then calculate the distance to the horizon from the observer.
== Measuring Electromagnetic Radiation (EMR) ==
:::Actually there is no need to use black holes at all. You can put a mirror on the Earth's surface and direct the laser beam at it from a remote ___location in space. Then since you know the distance and can measure the time when the reflected signal comes back you can calculate the speed by dividing the first quantity by the second. The result will be that the (apparent) speed of light is less than ''c''. [[User:Ruslik0|Ruslik]]_[[User Talk:Ruslik0|<span style="color:red">Zero</span>]] 10:39, 20 August 2025 (UTC)
Two part question:
::::I can see some practical issues with measuring the distance to a black hole. And also some theoretical issues. ​‑‑[[User talk:Lambiam#top|Lambiam]] 16:53, 20 August 2025 (UTC)
:::::Any black hole is just a mass. You need only to measure the orbital parameters of test particles moving around it. [[User:Ruslik0|Ruslik]]_[[User Talk:Ruslik0|<span style="color:red">Zero</span>]] 17:34, 20 August 2025 (UTC)
::This is far from the first time I have been exposed to these facts, but this concept still breaks my brain a little. I think it's on account of how we utilize the notion of an observer from an outside frame of reference as an abstraction. Obviously, in terms actual empirical observation at this point, the photon is completely red-shifted and has no chance of ever escaping. So it can't ever be directly observed. And yet we regard it as being unable to ever being able to be observed to have crossed the event horizon. Can someone help me with the structural distinction here? Because obviously if we had a photon's trajectory bent around the gravity well of a black hole (or any mass), we could observe it only by directly interacting with it by intercepting it somewhere along its path. So what do we mean when we talk about observation in an instance that is not in any scenario actually physically possible? ''[[User:Snow Rise|<b style="color:#19a0fd;">S</b><b style="color:#66c0fd">n</b><b style="color:#99d5fe;">o</b><b style="color:#b2dffe;">w</b><b style="color:#B27EB2;">Rise</b>]][[User talk:Snow Rise|<sup><b style="color:#d4143a"> let's rap</b></sup>]]'' 06:44, 24 August 2025 (UTC)
:::Just a small remark: '''<span style="color: red">"red-shifted"</span>''' (as you say), only when it tries to ''escape'' a black hole, but here we are talking about a photon ''approaching'' a black hole, so it's '''<span style="color: blue">blue-shifted</span>'''. [[Special:Contributions/2A06:C701:745A:B800:B559:3320:A4F4:C460|2A06:C701:745A:B800:B559:3320:A4F4:C460]] ([[User talk:2A06:C701:745A:B800:B559:3320:A4F4:C460|talk]]) 10:22, 24 August 2025 (UTC)
:::Regardless of their colour (frequency), photons can only be directly observed when they hit the observer. This was already pointed out above by Avocado. They can only be observed, directly or indirectly, when they are detected by some detector, which means in quantum terminology that they are "[[Measurement in quantum mechanics|measure]]d". Measurement of a photon means a change in a macroscopic system (a [[photoreceptor cell]] in the observer's eye, a [[photographic plate]] or [[photographic film|film]], a [[photodetector]], ...) as the result of an interaction with that system. Unless the measuring system is close to where the photon is, the probability of an interaction taking place is vanishingly small. ​‑‑[[User talk:Lambiam#top|Lambiam]] 12:05, 24 August 2025 (UTC)
::::Do you claim, any measurement (e.g. by a telescope or whatever) of the length of a photon's curved trajectory - whether near the sun - or in any phenomenon of gravitational lensing, is a local measurement? [[User:HOTmag|HOTmag]] ([[User talk:HOTmag|talk]]) 13:11, 24 August 2025 (UTC)
:::::Does [[Principle of locality]] help? {The poster formerly known as 87.81.230.195} [[Special:Contributions/90.210.150.115|90.210.150.115]] ([[User talk:90.210.150.115|talk]]) 18:03, 24 August 2025 (UTC)
::::I think you've mis-interpeted my inquiry here, {{u|Lambiam}}. As it happens, I'm a bit of an expert in visual cognition, and so very familiar with the physics/biophysics of photoreceptive media. That's not the part I am struggling to fix in my mind here. My epistemological confusion about the terminology is this: since a photon trapped at the event horizon never escapes to interact with such a medium, what do we mean when we talk about "observation" when, for example {{u|Ruslik0}} says {{tq|The light from the torch will travel in the direction of the event horizons but will never cross it (from the point of view of an external inertial observer).}}? Is it a conceptual conceit/misnomer for describing the relation of the frames of reference? If so, can you think of a thought experiment that would explain those interactions in such a way that accounts for the fact that, as a strictly empirical and ontological matter, no observation at a distance can be made? Maybe Ruslik0 just mixed their metaphors and terminology a bit? If not, I'm super confused as to what the act of observation means in that description. ''[[User:Snow Rise|<b style="color:#19a0fd;">S</b><b style="color:#66c0fd">n</b><b style="color:#99d5fe;">o</b><b style="color:#b2dffe;">w</b><b style="color:#B27EB2;">Rise</b>]][[User talk:Snow Rise|<sup><b style="color:#d4143a"> let's rap</b></sup>]]'' 22:10, 24 August 2025 (UTC)
:::::You are right, I misunderstood the essence of your post. My reaction was triggered by the statement connecting our inability to observe the photon to its colour, which is I think essentially correct – in the model its wavelength tends to zero as it approaches the event horizon – but irrelevant. Scenario's of a photon traveling to an event horizon can be described that conform to a mathematical model of GR, such as [[Schwarzschild metric|Schwarzschild's exact solution to Einstein's equations]]. Such descriptions need a frame of reference, preferably one that in the limit, away from the mass, is an inertial frame. I too think the wording of these scenario's is sometimes confused. The scenario may include an observer for which this frame is stationary who can observe phenomena as predicted by the model, which in real life would validate the model. But such observation can only be through information that reaches them from afar, such as transmitted by electromagnetic waves. An astronaut approaching the event horizon might broadcast a livestream witness report that reaches the observer, but a photon can do no such thing. The models do not allow an observer to observe the unfolding of the scenario with regard to the traveling photon, so describing the scenario in terms of observations is confused. ​‑‑[[User talk:Lambiam#top|Lambiam]] 23:58, 24 August 2025 (UTC)
:::::What I actually meant is [[shapiro time delay]], which can be interpreted as slowing of light in presence of a gravitational field. [[User:Ruslik0|Ruslik]]_[[User Talk:Ruslik0|<span style="color:red">Zero</span>]] 20:33, 25 August 2025 (UTC)
= August 26 =
What type of instrument is used to measure the amount of EMR put out by a small appliance.
== Pharmacology ==
What types of '''flexible''' matierials block EMR (i.e., mesh, aluminum, kevlar)?
A friend once mentioned a book similar to an Encyclopedia, describing background events behind the development of many well known medicines . Please inform if a similar book can be found and how to "custom search" at any of the sites of WIKI for such a book .
Thank you.
Thnx [[User:71.140.225.157Dr chifti|Dr chifti]] ([[User talk:Dr chifti|71.140.225.157talk]]) 0305:4605, 126 DecemberAugust 20052025 (UTC)
:You might find such a work used as one of the many references for the article [[History of medicine]], athough what you describe would be a [[Tertiary source]] (like Wikipedia itself) rather than a [[Secondary source]] which Wikipedia prefers for article sources.
:Searching Wikipedia for the term "Encyclopedia of pharmacology" led me to the article ''[[Pharmacology Research & Perspectives]]'' whch uses as its reference 4 ''The Sage Encyclopedia of Pharmacology and Society'' – see that article for its bibilographical details. {The poster formerly known as 87.81.230.195} [[Special:Contributions/90.210.150.115|90.210.150.115]] ([[User talk:90.210.150.115|talk]]) 08:04, 26 August 2025 (UTC)
:Searching Archive.org for [https://archive.org/search?query=history+of+medicines history of medicines] turns up many candidates, including [https://archive.org/details/ourmodernmedicin0000band/page/n7/mode/2up?view=theater Our Modern Medicines] (F Bandelin, 1986) which seems to match your description. <span class="nowrap">[[User:Verbarson|-- Verbarson ]] <sup>[[User talk:Verbarson|talk]]</sup><sub>[[Special:Contributions/Verbarson|edits]]</sub></span> 15:04, 26 August 2025 (UTC)
= August 27 =
:Any conductive material, if wrapped around the appliance without large holes, forms a [[Faraday cage]] that blocks low-frequency electromagnetic radiation. The maximum allowable hole size depends on the highest frequency that needs to be blocked. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 16:55, 1 December 2005 (UTC)
== [[Lorentz factor]] derivarion ==
== middle cerebral artery aneurysm ==
In '''[[special relativity]]''', a common way to derive the '''Lorentz factor''' <math>\gamma</math> is via the '''[[pythagorean theorem]]''', without using the complicated '''[[Lorentz transformations]]''' (which I myself have yet to study).
How can I treat a middle cerebral artery aneurysm?
:Well, I advise you seek professional help on this one. All I can do is mention the treatment section of [[aneurysm]], and point out also the article on [[cerebral aneurysm]]s. I didn't notice either of them specifically mentioning middle cerebral artery aneurysms. --[[User:ParkerHiggins|ParkerHiggins]] 07:17, 1 December 2005 (UTC)
:Please see a [[physician]], preferably the physician who diagnosed the condition. One cannot treat an MCA aneurysm by oneself. — [[User:Knowledge Seeker|Knowledge Seeker]] [[User talk:Knowledge Seeker|দ]] 07:44, 1 December 2005 (UTC)
By the equation
== how led actually work ==
:<math>(c\,{\rm T_s})^2=(v\,{\rm T_s})^2+(c\,{\rm T_v})^2</math>,
such that
:<math>c</math> [[speed of light]] in a vaccum
:<math>v</math> speed of a '''moving observer''' relative to a '''stationary observer'''
:<math>{\rm T_s}</math> stationary observer time
:<math>{\rm T_v}</math> moving observer time
hence
:<math>\gamma=\frac{\rm T_s}{\rm T_v}=\frac{1}{\sqrt{1-\big(\frac{v}{c}\big)^2}}</math>
My questions are as follows:
#Is this derivation actually legitimate, or does it contain any non-proven hidden assumptions?
#I have not yet seen any '''mathematical reasoning''' showing these transformations must be [[Linear map|'''linear''']].<br>In my humble opinion, most sources completely ignore this point, or treat it superficially at most.<br>I would like to know if there is any such reasoning.
#Why is the factor not written <math>\gamma(v)</math>?
[[User:יהודה שמחה ולדמן|יהודה שמחה ולדמן]] ([[User talk:יהודה שמחה ולדמן|talk]]) 15:29, 27 August 2025 (UTC)
:It is not clear where the first equation comes from. [[User:Ruslik0|Ruslik]]_[[User Talk:Ruslik0|<span style="color:red">Zero</span>]] 20:25, 27 August 2025 (UTC)
::Watch this short video [https://www.youtube.com/watch?v=67xr6EZEYV8 '''here''']. It is very common. [[User:יהודה שמחה ולדמן|יהודה שמחה ולדמן]] ([[User talk:יהודה שמחה ולדמן|talk]]) 04:11, 28 August 2025 (UTC)
:::That the equation is common doesn't mean it's clear where it comes from. It's not a priori clear that in a triangle with edges <math>cT_s</math>, <math>vT_s</math> and <math>cT_v</math> the latter two edges must be perpendicular. When I learned about special relativity, it started with the Lorentz transformations. Those aren't terribly hard; this was my first week at university. It could be done in the last year of secondary school. [[User:PiusImpavidus|PiusImpavidus]] ([[User talk:PiusImpavidus|talk]]) 09:14, 28 August 2025 (UTC)
:It's worth highlighting that the 4-space Lorenz transformations take place in is non-Euclidian. So it doesn't use the Euclidian metric, normally calculated with Pythagoras's theorem. Instead it uses a version with the squares of the three length components added but the time component subtracted.
:If you eliminate two of the length components this looks like a difference of squares. Rearrange these you get a sum and it looks like Pythagoras's theorem, but because it's been rearranged it isn't really the same thing. The minus sign in the the second expression more correctly expresses the metric. --[[Special:Contributions/217.23.224.20|217.23.224.20]] ([[User talk:217.23.224.20|talk]]) 10:38, 28 August 2025 (UTC)
:It is not clear who introduced the convention of using the Greek letter <math>\gamma</math> for the Lorentz factor (not Lorentz himself, nor Einstein, who used the letter <math>\beta</math> in "Zur Elektrodynamik bewegter Körper"*), but since it tends to be all over the place in derivations in special relativity, the one-letter notation is obviously more convenient than writing each time <math>\gamma(v)</math>. ​‑‑[[User talk:Lambiam#top|Lambiam]] 10:41, 28 August 2025 (UTC)
:<hr style="width:5em">
:{{*}}{{small|Perhaps [[Hans Bethe|Bethe]] in [https://link.springer.com/chapter/10.1007/978-3-642-52619-0_3 "Quantenmechanik der Ein- und Zwei-Elektronenprobleme" (1933)]. This is behind a paywall; I cannot check if he actually used this notation. ​‑‑[[User talk:Lambiam#top|Lambiam]] 11:08, 28 August 2025 (UTC)}}
::Bethe uses <math>\varepsilon = E/E_0</math> (his eq. 9.16; <math>E_0</math> is the rest energy), which is the Lorentz factor; I don't think he expresses it in terms of ''v'' and ''c'' anywhere. (Accessed via Wikipedia Library, which once again proved more powerful than my university account...). --[[User:Wrongfilter|Wrongfilter]] ([[User talk:Wrongfilter|talk]]) 11:34, 28 August 2025 (UTC)
'''To point 3:''' Writing <math>\gamma(v)</math> declares only that <math>\gamma</math> is a function of a variable <math>v</math> thus <math>\gamma = \gamma(v)</math>
Well, you might ask a question. But in lieu of that, may I suggest you check out [[Light-emitting diode]]? --[[User:ParkerHiggins|ParkerHiggins]] 06:48, 1 December 2005 (UTC)
which is true but conceals the nature of the function. Lorentz factor <math>\gamma</math> is a dimensionless ratio that is a non-linear function of a velocity <math>v</math> that for any real mass is constrained to be less than <math>c</math>. For a massless particle such as a photon, calculating <strike>a unity</strike>an infinite Lorentz factor adds no useful information.
'''To point 2:''' Given the Lorentz equation confirmed in Special relativity
:<math>\gamma=\frac{1}{\sqrt{1-\big(\frac{v}{c}\big)^2}}</math>
the OP chooses by algebraic reasoning to derive an arbitrary relation
:<math>(c\,{\rm T_s})^2=(v\,{\rm T_s})^2+(c\,{\rm T_v})^2</math>
but this result is flawed. It predicates two different observers each of whom would have to be moving at c, as only a photon can, if expressions
<math>(c\,{\rm T_s})</math> and <math>(c\,{\rm T_v})</math> are to be real distances moved in a real time interval. It is hard for me to conceive of even one photon observing another photon and somehow reporting an observed distance. I don't believe that Pythagoras who relied more on the geometrical axioms of Euclid ca. 300 BC than on Einstein publishing in 1905 would appreciate or endorse being cited here. I see no other good source for the latter "pseudo-Pythagorean" equation and I conclude that it is introduced here as algebraic sleght-of-hand. The trick is to quote a supposed definition
<math>\gamma=\frac{\rm T_s}{\rm T_v}</math>
into which the trickster plugs <math>\rm T_s</math> and
<math>\rm T_v</math> that have been synthesized to give the standard result.
'''To point 1:''' The ploy is clever but hardly legitimate. [[Special:Contributions/2A02:FE1:4088:5E00:DC53:CFFC:3F4A:F5BE|2A02:FE1:4088:5E00:DC53:CFFC:3F4A:F5BE]] ([[User talk:2A02:FE1:4088:5E00:DC53:CFFC:3F4A:F5BE|talk]]) 15:33, 28 August 2025 (UTC)
:This is not a "Pseudo-Pythagorean" equation.
== *.m4a to *.wma ==
:Perhaps [https://www.youtube.com/watch?v=qXxtqK7G4Uw&t=160s '''this derivation here'''] will be even clearer.
:I do apologise for not being able to show a geometric sketch in advance. [[User:יהודה שמחה ולדמן|יהודה שמחה ולדמן]] ([[User talk:יהודה שמחה ולדמן|talk]]) 18:27, 28 August 2025 (UTC)
::Isn't this the same derivation as given in {{section link|Time dilation#Simple inference}}?
::The presentation in the YouTube video is (IMO) in one respect somewhat confusing. There are two observers, one inside a moving train car, one standing outside next to the railroad tracks in the grass. There are two time values for the different times clocked by these observers, <math>T_{stationary}</math> and <math>T_{moving}.</math> Now in the narrative of the video <math>T_{stationary}</math> stands for the time clocked by the observer in the ''moving'' car, while <math>T_{moving}</math> is the time clocked by the observer patiently ''standing'' outside till this ordeal is over. I beg your pardon. (To be fair, the narrative gives a reasonable explanation for this choice, but note that the notation in the question has this swapped: <math>{\rm T_s}=T_{moving}</math> and <math>{\rm T_v}=T_{stationary}.</math>)
::The simple derivation given is based on vector decomposition of a velocity into a component in a given direction (in this case that of the velocity of the moving car) and an orthogonal component, and that this remains valid for a moving system observed from the outside. I don't know if this can be called an assumption – if so, it is hardly hidden — but the validity of this step may not be that obvious to the confused student all of whose implicit assumptions based on the Newtonian model of absolute time and space have lost their certainty and who may wonder what happened to length contraction.
::The presenter himself states that this is not his favourite derivation, and that there is a better, but more difficult explanation. ​‑‑[[User talk:Lambiam#top|Lambiam]] 08:47, 31 August 2025 (UTC)
= August 31 =
How can one convert a .m4a file format (songs from iTunes) to *.wma file format (so i can play them in windows media player...)?
:There's a winamp plugin that lets it play m4a. So you can use winamp to play them, or you can use winamp to decode it to a wav (and then you can use any of a dozen programs to reencode it as an mp3) [[User:Raul654|Raul654]] 10:58, 1 December 2005 (UTC)
::However, note that every time you convert from one [[lossy]] format to another, it sounds a little worse. Encoding from the original source is always better. —[[User:Keenan Pepper|Keenan Pepper]] 15:20, 1 December 2005 (UTC)
== Cookie files ==
Does anyone know why the term "cookie" was used in the first place? (I can see the link for developing the brownie project, but why did he choose "cookie" to start with)?
All ideas gratefully accepted.
Jax1402
:The original, full term is ''[[magic cookie]]''. I think it may have originated at MIT; MIT-MAGIC-COOKIE-1 is an authentication method used by the [[X Window System]]. —[[User:Keenan Pepper|Keenan Pepper]] 18:05, 1 December 2005 (UTC)
== How do you "turn off" a magnet? ==
How do you turn off a magnet?
This is NOT an electro-magnet.
I have a magnetic base for a measuring device that allows you to attach the measuring device to metal objects. The magnetic base has a switch that allows you to turn the magnet on or off. When on, the magnet is very powerfull, and when off, it will attract and hold a paper clip but nothing bigger.
I dissassembled the magnetic base on found that it consists of a block of metal with a cylindrical hole drilled thru its center. In the hole is a cynlindrical magnet. The switch rotates the cylindrical magnet 90 degrees. The outer block does not have any measurable magnetism.
:Your description is a bit value, but I'll assume the [[dipole]] axis of the magnet is perpendicular to the axis of the cylinder, i.e. that rotating the magnet in the hole moves the poles, and that in the "on" position one of the poles points towards the bottom of the base. That pole then strongly attracts adjacent [[ferromagnetic]] objects. When you rotate the magnet 90°, both poles as now facing the sides of the base (where there is presumably quite a lot of padding between the magnet and the exterior of the base), while the side of the magnet produces only a weak residual attraction. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 16:44, 1 December 2005 (UTC)
*Actually, it's usually the opposite way around. When the magnet is "off", the dipole points up and down. When it is "on", the rotating magnet has its N pole in one half of the base, and the S pole in the other half. The two halves of the base plus the rotating magnet form a sort of horseshoe magnet. When its attached to a piece of metal (across the two halves of the base) it makes a magnetic circuit which it is very strong. When it is switched off, there's a much smaller residual magnetism. These sort of bases are used a lot in optical experiments to position devices on optical benches. See here: {{US patent|4251791}} for one design. --[[User:DrBob|Bob Mellish]] 21:34, 1 December 2005 (UTC)
Heat it up --[[User:Eye|Eye]] 21:37, 1 December 2005 (UTC)
:I agree with Eye - what you want to do is to disrupt the alignment of the dipoles in some manner. Nothing quite like heating or hitting the magnet. --[[User:HappyCamper|HappyCamper]] 03:32, 3 December 2005 (UTC)
[[Degaussing]]. ☢ [[User:Kieff|Ҡieff]]⌇[[User_talk:Kieff|↯]] 01:30, 6 December 2005 (UTC)
== What to do with an extra satellite dish? ==
Last week an article about a guy with a dozen satellite dishes outside his house was linked everywhere on the internet. This morning I stopped by my mothers house and they recently had their DirectTV dish replaced with one that can pick up local channels. They got to keep their old dish...until I stole it from them. What do I need to do to set this sucker up on my apartment balcony and start getting news feeds, local channels from other states, and shows in languages I don't speak?
I know I need a receiver but could I just use a computer and some software made for this?
Is there any other fun things I can do with this dish?
[[Frisbee]]! Make a giant [[Pu pu platter]]! Makes a great shield for those slow [[Dungeons and Dragons]] game nights. You need an account for those dishes, so I doubt you will pick up much free programming. [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 19:08, 1 December 2005 (UTC)
:It'd make a tremendous [[parabolic microphone]]. –[[User:Mysid|Mysid]] 10:51, 2 December 2005 (UTC)
::[[Snowboard]]! <font style="color:#CC0000"><u><b>s</b>murray</u></font><font style="color:#DD0000"><u>in</u></font><font style ="color:#EE0000"><u>chester</u></font><font style="color:#55BB22"><sup>([[User:Smurrayinchester|User]]), ([[User talk:Smurrayinchester|Ho Ho Ho!]])</sup></font> 12:51, 2 December 2005 (UTC)
:::Point it straight up and try to beat SETI to the punch. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 02:54, 3 December 2005 (UTC)
:[[Bird bath]]? [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 03:23, 3 December 2005 (UTC)
== Microbrewing ==
How does micro brewing work?
:See [[Microbrew]]. I think it's just like regular brewing, only on a smaller scale. [[Homebrewing]] is even smaller. —[[User:Keenan Pepper|Keenan Pepper]] 18:12, 1 December 2005 (UTC)
::[[Microbrewery]] too. --[[User:HappyCamper|HappyCamper]] 03:31, 3 December 2005 (UTC)
== mathematics ==
what is the maximum number of vertices with 15 edges and three components?
:If you have V vertices and E edges, the minimum number of components is V − E (because if there are no edges, each vertex is its own component, and each new edge can only reduce the number of components by one). In this case we need <math>V - 15 \le 3</math>, so the maximum value of V is 18.
:Also, please ask mathematics questions at the [[Wikipedia:Reference desk/Mathematics|Mathematics reference desk]]. —[[User:Keenan Pepper|Keenan Pepper]] 18:25, 1 December 2005 (UTC)
== accidental huffing ==
Today I took of water from a water fountain. After I had lowered my head towards the faucet, I could smell cleaner fumes. This upset me because I inhaled the fumes while being close to the source of the fumes. I'd like to know if this is the equivalent of huffing, because I'm scared of being brain damaged from the fumes.
:Wikipedia does not generally give medical advice, so if you're really worried, go talk to your doctor. However, I suspect it was harmless. The effects of [[inhalant]]s are usually acute rather than chronic, which means you get dizzy and even pass out before doing any permanent damage (unless it becomes a habit, of course). —[[User:Keenan Pepper|Keenan Pepper]] 18:32, 1 December 2005 (UTC)
::You may be suffering from [[hypochondria]]. I mean, c'mon, how long were you inhaling the fumes for? [[User:Nricardo|Nelson Ricardo]] 05:10, 2 December 2005 (UTC)
:::I think there are bigger problems if your water fountains are producing fumes. Water vapor is not a fume, nor ought it to have a smell. --[[User:YixilTesiphon|YixilTesiphon]] 06:19, 2 December 2005 (UTC)
::::If you live anywhere near a sizeable built-up area you'll likely be inhaling exhaust fumes all the time (every breath you take, day and night). Living next to a busy road is like being a heavy smoker. I base this on tests done on children in [[Maastricht]], not quite a big town. The traffic is nothing compared to that of a modern big city, let alone the ones in the US (eg LA) or third world countries. If you want to worry about something worry about that. [[User:DirkvdM|DirkvdM]] 10:43, 2 December 2005 (UTC)
::I once measured the [[carbon monoxide]] levels in central [[Zurich]] ([[Switzerland]]: [[population]] 366,145) to prove to my collleagues that they were not allowed to go downtown during working hours (and, incidentally, to prove that our lab met Swiss occupational health standards). [[User:Physchim62|Physchim62]] [[User talk:Physchim62|(talk)]] 12:36, 4 December 2005 (UTC)
== How Does An Alkaline Component of Laundry Detergnets and Cleaners Clean==
How does an alkaline/base component of detergents and cleaners make a stain more soluble? In other words, how does it dissolve the stain?--Just Wondering
They clean as [[Surfactant|Surfactants]] by lowering the [[surface tension]] of water. Many alkaline substances also allow oils to be [[emulsified]]. Look at [[Alkali]]. [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 19:04, 1 December 2005 (UTC)
:This is sort of a trick question, because it really depends on the chemistry of the laundry detergent. Which brand are you using? --[[User:HappyCamper|HappyCamper]] 03:29, 3 December 2005 (UTC)
Dear Happy Camper,
The laundry detergent used was good old fashioned ''Arm and Hammer Washing Soda.''
A 1/2 tablespoon was put in 16 ounces of hot water with no other detergent (water is "soft") to remove an olive oil stain from cotton. A half an hour later, Voila,! No stain. How did it dissolve the stain.
Thanks for your help and ny others.
--Just Wondering
== density of water ==
The [[density]] of [[water]] indeed. You might also want to see [[Water_%28molecule%29#Density_of_water_and_ice|density of water and ice]]. --[[User:Borbrav|Borbrav]] 23:25, 1 December 2005 (UTC)
The density of water is the reference value for [[specific gravity]]; water is defined to have a specific gravity of 1. {{User:Eequor/Signature/Syllabic}} 00:01, 2 December 2005 (UTC)
=December 2=
== New Firefox version and its search engines ==
Hi,
For some reason the Wikipedia search engine that came with the previous version of Mozilla's Firefox browser (I'm using the most recent update) is now gone! Why is that, and does the company plan on bringing it back? I can't seem to find a place to ask at its website. --[[User:71.103.127.114|71.103.127.114]] 00:18, 2 December 2005 (UTC)
:You can add the Wikipedia search engine plugin by clicking on the "Wikipedia" link on the following page: [https://addons.mozilla.org/search-engines.php Search Engines]. Be sure you have javascript enabled. You can also go to the same page by selecting "Add Engines..." from the drop-down list in the Firefox search box. --<br /> Mark Bornfeld DDS<br/>[http://www.dentaltwins.com dentaltwins.com]<br/>Brooklyn, NY 01:07, 2 December 2005 (UTC)
::Holy crap, you're right! Thanks Mark. --[[User:YixilTesiphon|YixilTesiphon]] 05:52, 2 December 2005 (UTC)
== Hercules (constellation) ==
Hi am doind a science project and am having a hard time finding out why the "stars" were named after him. Could you please help.
thankyou
:[[Hercules (constellation)]] says that it's identification with Hercules might have to do with it's proximity to [[Sagitta]] (identified as an arrow) and [[Aquila (constellation)]] (identified as a bird); the three together can be read as an illustration of one of Hercules's [[Twelve Labors]]. There's many potential connections, so you might be interested in particular in [[The Twelve Labours#Connection to the Zodiac]]. — [[User:Laurascudder|Laura Scudder]] [[User talk:Laurascudder|☎]] 03:57, 2 December 2005 (UTC)
:Why? Because somebody felt like it. Honest answer. Most likely, it's in your textbook. --[[User:YixilTesiphon|YixilTesiphon]] 05:53, 2 December 2005 (UTC)
::According to [[Robert Burnham, Jr.]] in ''Burnham's Celestial Handbook'', Hercules was one of the earliest star patterns to be defined and was identified with national heros or gods from very ancient times in the [[Near East]]. Burnham says that in [[Mesopotamia]] the star group was associated with the sun-god [[Izhdubar]], the legendary hunter [[Nimrod]], and with [[Gilgamesh]] of the flood legend. The ancient [[Phonecia|Phonecians]] saw it as the god [[Melqart|Melkarth]]. Later, in ancient Greece, the constellation came to be associated with the hero [[Heracles]], or Hercules. It's unlikely that it will ever be known exactly "why" this constellation was identified with a god or hero originally, but given that history, it is understandable that the Greeks came to name it for ''their'' great national hero. --[[User:DannyZ|DannyZ]] 06:08, 4 December 2005 (UTC)
== Extracting information from the web (datamining) ==
How would I go about writing a program to extract data from a website (ie the sales rank of books on amazon.com)?
:In principle, you'd write a program that simulated a browser connection to fetch information from a web site, perhaps using URLs you list in advance, or a web spidering system. Then you'd parse the HTML, assuming unchanging formats, to get the book info and rank. Then analysing it would be easy. In practice, if you plan to get all books rather than just a handful, this would hit Amazon's servers hard (perhaps as hard as thousands of customers). They are likely to have methods in place to detect this, assume they are under attack, and block your connection temporarily or permanently. Not recommended. [[User:Notinasnaid|Notinasnaid]] 09:41, 2 December 2005 (UTC)
:Not sure what you mean, but [[HTTrack]] will let you download the entire Internet if you wish. Careful though, it's extremely powerful and you may get more than you bargained for. [[User:DirkvdM|DirkvdM]] 10:49, 2 December 2005 (UTC)
: [[Perl]] is good for problems that need a lot of text manipulation, as this does. The usual [[module (Perl)|module]]s for making [[HTTP]] requests are comprised by the [[libwww-perl]] collection (LWP) [http://lwp.linpro.no/lwp/], and there are a number of modules available for constructing requests (''e.g.'' [[HTML::Form]]) and parsing [[HTML]] ([[HTML::Parser]]), which can be obtained from [[CPAN]]. {{User:Eequor/Signature/Syllabic}} 10:51, 2 December 2005 (UTC)
:It's also good to check if the website has an RSS feed available that you can easily extract data with; PHP has some good XML parsing functions you could use. Though if Amazon doesn't issue RSS i'd suggest the above. [[User:Benbread|-Benbread]] 15:40, 2 December 2005 (UTC)
:Actually, Amazon [http://www.amazon.com/gp/browse.html/ref=sc_fe_c_0_15763381_2/102-8755066-1273724?%5Fencoding=UTF8&node=12738641&no=15763381&me=A36L942TSJ2AJA has an API] to make this sort of thing much easier. I think it probably has sales rank. [[User:Superm401|Superm401]] | [[User_talk:Superm401|Talk]] 00:09, 3 December 2005 (UTC)
== Can the use of mobile phones by pregnant woman, can harm the fetus? ==
Sir/Madam,
Iam Sudha, from Tamil Nadu,India.
If a pregnant women, who uses cell phones / mobile phones in her daily life, will the fetus (unborn baby)inside her will be affected if she continues using cell phones?
Can you please answer this question, as early as possible?
Regards
Sudha --[[User:59.144.4.84|59.144.4.84]] 06:34, 2 December 2005 (UTC)
::Sudha,
::According to [[Mobile phone radiation and health]], the risk of radiation from cell phone use is, as yet, unsubstantiated. However, as the article says "the World Health Organization has recommended that the precautionary principle could be voluntarily adopted in this case." So, I would say that the baby will be fine, provided the mother isn't ''always'' on the phone. I hope that helps to answer your question. --[[User:ParkerHiggins|ParkerHiggins]] 07:04, 2 December 2005 (UTC)
*Even if phones provide a health risk, the radiation it cause is only powerful enough to reach the woman's own brain which shouldn't have any direct influence on the fetus. Of course, effects on the mother will eventually affect the child psychologically if they turn out to be severe in the long run. I would recommend cutting down phone usage anyway. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 09:40, 2 December 2005 (UTC)
:Note that cellphones use electromagnetic radiation in the [[microwave]] range, so see the above discussion on the dangers (or lack thereof) of microwaves. —[[User:Keenan Pepper|Keenan Pepper]] 18:38, 2 December 2005 (UTC)
::I imagine that if there were any grave danger, a humongous increase in the number of [[birth defects]] would have been observed. It hasn't, so there's probably nothing wrong. --[[User:YixilTesiphon|YixilTesiphon]] 00:12, 3 December 2005 (UTC)
== hot water ==
Does hot water contain more air than cold water?
:No, the solubility of most gases (I want to say ''all gases'', but there may be weird exceptions?...) decreases as temperature increases. A common example of this is [[carbonated water]], which quickly goes flat on a hot day but keeps its carbonation for a long time when chilled. The reason for this is that, at a higher temperature, the gas particles move faster, and they can more easily escape from the surface of the solution (the [[vapor pressure]] is higher). So, the capacity of hot water to contain dissolved air is less than that of cold water. —[[User:Keenan Pepper|Keenan Pepper]] 18:47, 2 December 2005 (UTC)
::Which is why ice cubes made from boiled water (less air) are clearer. --[[User:Hydnjo|hydnjo]] [[User talk:Hydnjo|talk]] 20:31, 2 December 2005 (UTC)
:::Huh? Wouldn't additional air just dissolve as the ice cooled before freezing? [[User:Superm401|Superm401]] | [[User_talk:Superm401|Talk]] 00:11, 3 December 2005 (UTC)
::::Huh? indeed...Things can't dissolve in a solid. --[[User:YixilTesiphon|YixilTesiphon]] 00:13, 3 December 2005 (UTC)
:::::That's certainly not true. What do you think an [[alloy]] is? [[User:Superm401|Superm401]] | [[User_talk:Superm401|Talk]] 02:50, 3 December 2005 (UTC)
::::::Bad phrasing on my part. Gasses are already dissolved (unless they are forming bubbles), so Suprm401's question doesn't make any sense. --[[User:YixilTesiphon|YixilTesiphon]] 03:16, 3 December 2005 (UTC)
:::::::Huh? Let's take a step back and see:
:::::::''Does hot water contain air more than cold water?'' The answer is ''no'' - this is because the solubility of air (ie, mostly nitrogen and oxygen) in water ''decreases'' as you increase the temperature. Keenan's example of soda is an excellent everyday example of this general observation - hot [[coca cola]] certainly doesn't have quite the fizz as a cold one! Ditto with beer.
:::::::As for the ice cubes - that's also the reason why boiled ice cubes look clearer - during the boiling process, most of the dissolved gasses escape. Hence, when you make ice cubes, no bubbles come out during the freezing process.
:::::::An [[alloy]] is an example of a ''[[solid solution]]''. And yes, things can "dissolve" in a solid - however, it's a bit more of a subtle concept here. In this case, it depends on how you define "dissolve" - it may not necessarily mean "[[solvation]]". However, in certain fields of chemistry, it is desirable to restrict the definition to liquid solutions. I hope this clarifies things! --[[User:HappyCamper|HappyCamper]] 03:23, 3 December 2005 (UTC)
::::::::Almost forgot: REgarding Superm401's question - yes, some air will redissolve back into the water when it cools, but the difference is that the rate of freezing is significantly higher than the rate at which the air dissolves. --[[User:HappyCamper|HappyCamper]] 03:24, 3 December 2005 (UTC)
:*(exdenting for readability) Quiz question: Why are icicles clear? --[[User:Hydnjo|hydnjo]] [[User talk:Hydnjo|talk]] 03:38, 3 December 2005 (UTC)
:::They look clear because the freezing is incremental - but if you slice one, you will notice that there is a tendency for these bubbles to form in the center...so I guess they aren't really clear... --[[User:HappyCamper|HappyCamper]] 03:40, 3 December 2005 (UTC)
::::Hmmm... one doesn't slice icicles, they're meant to be bitten. But I guess the result would be the same. :-) --[[User:Hydnjo|hydnjo]] [[User talk:Hydnjo|talk]] 03:47, 3 December 2005 (UTC)
:::::Is "icicle" generally used for the outdoors variety? So [[User:Hydnjo|hydnjo]], it's regular to get an icicle off a tree and eat it? Just curious. --[[User:Commander Keane|Commander Keane]] 13:36, 3 December 2005 (UTC)
::::::A common practice indeed for children in the northeast US anyway. Icicles from roofs in particular because they can get pretty big. --[[User:Hydnjo|hydnjo]] [[User talk:Hydnjo|talk]] 15:51, 3 December 2005 (UTC)
:::::::Ironically the picture at the bottom of [[Ice]] shows icicles formed on a roof in Australia, even though I live in Austrlaia (and have never seen snow/ice) and was unware of the use of icicles.--[[User:Commander Keane|Commander Keane]] 17:56, 3 December 2005 (UTC)
::::::::I'm amazed! Snow and icicles in Australia! It's also interesting to see where the original question has taken us. --[[User:Hydnjo|hydnjo]] [[User talk:Hydnjo|talk]] 20:07, 3 December 2005 (UTC)
==Lens & water==
What happens when a liquid is inserted between a convex lens of focal length 20 cm and a plane mirror?plz give a detailed answer.
*There's no general answer; it depends on the liquid (in particular its [[refractive index]]), what material the lens is made out of, the exact form of the lens (e.g. radius of curvature of each surface), and the distance between the lens and the mirror. Very roughly, adding the liquid will increase the [[optical path length]] between the lens and the mirror; but the exact effect will depend on the parameters above. --[[User:DrBob|Bob Mellish]] 17:36, 2 December 2005 (UTC)
:What do you mean by ''inserted''? Is a tank of water placed between the lens and the mirror, or is the whole setup submerged in water? It makes a big difference. —[[User:Keenan Pepper|Keenan Pepper]] 18:58, 2 December 2005 (UTC)
:He means exactly what his teacher means, I suspect. (do your own homework)[[User:Superm401|Superm401]] | [[User_talk:Superm401|Talk]] 00:13, 3 December 2005 (UTC)
*Do your own homework. It's a little offensive when you give exact numbers (thus indicating that this is a homework problem), and say "plz give a detailed answer." --[[User:YixilTesiphon|YixilTesiphon]] 00:14, 3 December 2005 (UTC)
::Hmm..."offensive" might be going a little bit over the top here I think. We need more background information about the question in order to help you better. Are you trying to find the effect of looking through the combination of lens-water-glass, as opposed to lens-air-glass? --[[User:HappyCamper|HappyCamper]] 03:15, 3 December 2005 (UTC)
* I think you guys are overthinking this one a little. It seems pretty straightforward to me.
:Q. What happens when liquid is inserted between a convex lens and a plane mirror?
:A. They get wet.
--[[User:DavidConrad|DavidConrad]] 04:48, 7 December 2005 (UTC)
== Order and names of the Periodic Table groups ==
Hey
There seems to be some dispute over the numbers of the groups in the Periodic Table - I live in the UK and i've always been taught there are groups 1-0/8 and the transition metals, with these being named because of the number of electrons in their outer shell. While wikipedia and other sources state there are 18 groups. I'm assuming that the 18 groups is correct, but where is there some difference of opinion among people?
Thanks :)
[[User:Benbread|-Benbread]] 15:35, 2 December 2005 (UTC)
:Well, looking at [[periodic table]] I discovered, as I hoped, [[Periodic_table#Group_numbers|a section explaining this]], albeit briefly. Basically, it seems the 1-8 plus transition metals scheme isn't entirely unambiguous, so is officially "deprecated" by the shadowy bodies that get to decide such things... - [[User:IMSoP|IMSoP]] 19:48, 2 December 2005 (UTC)
*There's a slightly longer explaination at [[periodic table group]]. --[[User:DrBob|Bob Mellish]] 20:10, 2 December 2005 (UTC)
::The naming isn't so much a "dispute" - it is more a reflection of our better understanding of chemistry from a quantum mechanical perspective. In particular, the [[IUPAC]] recommended the renaming a few years ago. The old grouping of systems is still useful for teaching purposes though. --[[User:HappyCamper|HappyCamper]] 03:14, 3 December 2005 (UTC)
== illness ==
i am a 44 yo female i was diagnosed 3 years ago with rsd, since then i have been diagnosed with ulner noropathy degenerative disc disease rhumatoid arthritis(severe 242) fibromyalgia have bulging disc in c4567 and sudden platelett count drop any ideas. drs here are stumped and cant seem to offer any new help. you may e-mail me at <email removed>
*Please read the instructions at the top of the page. Leaving your email address here will almost certainly gets you loads of SPAM. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 22:09, 2 December 2005 (UTC)
I am sorry for your combination of problems, which sounds like way more than any one person deserves. It is difficult to give you a simple answer to your question for many reasons:
#You may actually have a combination of problems and there is no unitary answer to be had. It is always more gratifying for both patient and doctor if a single disease can be recognized that explains all of a person's problems, but that is unfortunately the exception rather than the rule.
#But having said that, it is still likely that some of them are connected to each other, statistically if not causally. For example, a common cause of platelet drop ([[thrombocytopenia]]) can be a drug effect. Have you started anything new recently? You might want to check whether thrombocytopenia is listed as a side effect of any of the drugs you take. That doesn't prove a causal relationship, but it gives you some choices of what to do. Another cause of sudden platelet drop is a viral illness. The platelets usually return to normal within a couple of weeks. Some people can develop [[autoimmunity]] to their own platelets, especially when they have other autoimmune or inflammatory diseases like [[rheumatoid arthritis]].
#If you have not asked your primary doctor for referral to a [[rheumatology|rheumatologist]] you might try that. They get lots of people referred for mysterious inflammatory conditions.
Good luck. [[User:Alteripse|alteripse]] 01:22, 3 December 2005 (UTC)
== I need something back!==
You know when you type in the name of something and save it and it says 'do you want to replace the article of the same name', is there any way you can get the article you deleted back? Its very important and I couldn't possibly do it again. Thanks! ----[[User:XenoNeon|XenoNeon]] 18:47, 2 December 2005 (UTC)
:Are you referring to replacing a Wikipedia article? --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 19:25, 2 December 2005 (UTC)
No. A word document. Will it be anywhere in the computer after you deleted it?--[[User:XenoNeon|XenoNeon]] 10:31, 3 December 2005 (UTC)
*Doubtful. Try searching and see, maybe it's stored somewhere in temp files (remember to look in hidden and system files), but you're in bad straits here. --[[User:YixilTesiphon|YixilTesiphon]] 13:34, 3 December 2005 (UTC)
Norton Antivirus 2004 offers a recycle bin which 'catches' and files deleted by whatever means (even non-manual) technically the file will probably still exist on your hard drive, but recovering it can be difficult and expensive, however, if the file is very important it is probably worth looking into professional help to recover it. The police use this method all the time, if a file is deleted it will still exist on your harddrive, however, the more times it is overwritten the harder and more expensive it is to recover it. - Unregisterd User 18:13 3 December 2005
== A Question regarding paraffin...from ''e-mail address removed'' ==
Where can one purchase paraffin for arthritic joint therapy, and about how much does it cost?
:Better not post your e-mail address here. You don't want to get even ''more'' spam, do you? —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 00:44, 3 December 2005 (UTC)
Go to google and then choose froogle. Enter parafin, and you get lots of choices: [http://froogle.google.com/froogle?q=parafin&hl=en&btnG=Search+Froogle&lmode=unknown] [[User:Alteripse|alteripse]] 12:58, 3 December 2005 (UTC)
== STI's and AIDS related ==
All I'm really asking is, how did all these dangerous epidermic happened? I mean, if we could go back in time, and say there are 100,000 males and females divided equally, all are all healthy individuals, how can STI and AIDS (or HIV) happened/started??
:The answer is in [[evolution]] and [[mutation]]. Depending on how far back you want to go, we could assume [[bacteria]], [[virus]]es, and [[protozoa]] exist (for simplicity we'll ignore multicellular organisms that live as [[parasites]]). Mutations in these agents can alter their [[virulence]] and [[transmission (medicine)]]--that is, the amount of damage they do and their ability to move from one host to another. As such, a virus or [[retrovirus]] that infects one type of organism could mutate to infect humans. This is believed to be the origin of the HIV strains that infect humans (see [[AIDS]] article) and is the crux of the recent global fear of an [[avian influenza]] [[pandemic]].
:The origins of [[infectious disease]] in general are older and less clear. But [[biological interaction]]s are as old as life itself, and are seldom friendly (see [[food chain]]). Viruses may have arisen from a bit of host genome mutated to produce large amounts of a virion even at penalty to the host.
:[[User:IlliniWikipedian|IlliniWikipedian]] 21:35, 2 December 2005 (UTC)
::IlliniWikipedian is absolutely correct. There was likely no time in the past where the entire population was disease-free. Bacteria and viruses predate the origin of humans. Disease is ancient. Our primate ancestors had infections before we evolved. Furthermore, even suppose you were granted a wish and you wished all disease-causing entities to instantly die, it would not be the end of (infectious) disease. Vast niches would now be free, and it would only be a short time before some of the remaining, innocuous bacteria evolved to parasitize and cause disease in humans and other organisms. With regards specifically to [[HIV]], the virus that causes [[AIDS]]: there is a related virus, a [[simian immunodeficiency virus]], which causes an AIDS-like disease in monkeys. One strain of this was transmitted from chimpanzees (our closest relatives) to humans in sub-Saharan Africa and evolved into what we now call HIV-1, the predominant form of HIV. A different strain evolved into HIV-2, which still only exists primarily in Africa. — [[User:Knowledge Seeker|Knowledge Seeker]] [[User talk:Knowledge Seeker|দ]] 23:10, 2 December 2005 (UTC)
:A problem here might be black and white thinking, the idea that certain organisms are purely bad. Where organisms live together they are likely to start interacting in some way. Sometimes this will result in one predating on the other, not with malicious intent, that's just the way things work. These we then call diseases when they're small (unless we want to consider ourselves a disease for the world's population of cows and such). At other times the interaction will be to the benefit of both, which we then call [[symbiosis]]. These interactions will always have happened, so there will always have been and always will be diseases (as already pointed out). [[User:DirkvdM|DirkvdM]] 09:53, 4 December 2005 (UTC)
== Help figuring out the components of a chemical reaction ==
Once I was flipping through a book of chemistry abstracts. I found one that described a reaction, the by products of which where C02 (sry don't know how to make subscript) and ethanol.
There was some discussion following that it could be used to make alcoholic soda pop tablets.
(Reagents + Flavoring)Compressed into a tablet + Glass of Water = Adult Soda.
I saw this year ago, and have gone back to the science library and tried to find it, but to no avail.
Does anyone have any idea what would have been used?
*Any [[weak acid]] and [[baking soda]], most likely. The gas produced when you mix [[Acetic acid|vinegar]] and baking soda is CO2. Another acid often used for this purpose is [[malic acid]]. --[[User:YixilTesiphon|YixilTesiphon]] 00:17, 3 December 2005 (UTC)
:Are you thinking of the powdered '[[alcopop]]' beverages being sold in Europe? One of the brand names is ''Subyou'' [http://www.subyou.com], but I imagine that there are or will be others.
:My understanding is that the powdered just-add-water beverage is based on ethanol encapsulation. Droplets of mixed water, [[ethanol]], and [[starch]] ([[dextrin]] or the like—something water soluble and flavourless) are dried under controlled conditions. The starch traps most of the ethanol molecules but allows the smaller water molecules to escape. The 'dry' Subyou powder is about 30% ethanol by weight. Adding water redissolves the dextrin and releases the alcohol back into solution. There are several variations on this encapsulation scheme.
:As YixilTesiphon mentions above, there are lots of chemical reactions that will generate CO<sub>2</sub> when you add water. A powder containing a mixture of dry acid and dry [[carbonate]] or hydrogen carbonate (bicarbonate) compounds will certainly do it. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 01:16, 3 December 2005 (UTC)
I think the powdered alchopop thing is closer to what I was thinking of. It was years ago that I saw it, but in my memory the chems in it actually reacted in solution to produce the ethanol and the CO2. That may not have been hte case though.
Why bother adding water? Adult pop-rocks anyone? [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 15:58, 3 December 2005 (UTC)
:Well, whatever pop-rocks are made out of is probably [[Polar molecule|polar]], so [[ethanol]] could dissolve. Sounds like fun.--[[User:YixilTesiphon|YixilTesiphon]] [[User talk:YixilTesiphon|Say hello]] 16:03, 3 December 2005 (UTC)
Well - I think the only thing that'll put my obsessive mind to rest is finding the article. Thanks all.
== Annealing Point ==
What is an [[annealing point]]? The [[glass|glass article]] makes refernce to it but doesn't explain it. The article just saying that glass's annealing point is 600 C. -- [[User:King of Hearts]] 23:43, 2 December 2005 (UTC)
:"Point" might be misleading, because it's fairly arbitrary: "When glass has been heated to a high enough temperature, it must be cooled by a controlled schedule of time and temperature or it will crack simply because of the strain inside the glass from the outside cooling faster than the inside. The sound of cracking glass in the waste buckets is common in glass studios. The thicker the glass, the longer the cooling time must be, days and weeks in the case of really thick castings. The annealing temperature is determined by slowly heating a long thin piece of glass supported at the ends until it just starts to sag (the sag temperature) and the annealing temperature is taken to be 50°C (90°F) below that, usually about 900F (480C). When scientific measurements are possible, the annealing point is a specific viscosity. "annealing point, AP—the temperature corresponding to a rate of elongation of 0.0136 cm/min when measured by ASTM Method C 336, Test for Annealing Point and Strain Point of Glass by Fiber Elongation. This test prescribes a rate of cooling of approximately 4 C/min with a fiber of approximately 0.065 cm in diameter, and a suspended load of 1000 g. The annealing point numerically approximates log = 13.0 poises, where internal stress is substantially relieved in a few minutes."" [http://users.ticnet.com/mikefirth/glosothr.htm] - [[User:Nunh-huh|Nunh-huh]] 23:48, 2 December 2005 (UTC)
Our article is at [[Annealing]]. I've created a redirect from [[annealing point]] to it.-[[User:Gadfium|gadfium]] 01:22, 3 December 2005 (UTC)
=December 3=
== Red Maple Tree ==
Hi, I'm helping my daugther with a tree project-Red Maple Tree and there are a few questions we needed to research to be able to do this project. First of all we had to pick a tree in our area to do the study on (Red Maple Tree). 1.How do you estimate the age of the tree by it's circumference? 2.The tree's habitat would be what (Where we live?)? The Red Maple's connection to technology and human wants and needs? 3.And very important the lif cycle of R.M.T.-this is a must have, all we could find are a basic tree cycle not necesary for R.M.T. And any other useful information that we could use in her report and Hypothesis-whether it blossoms flowers and what the seeds look like. We did find some general info, but not enough.
Thank you so much for any information that you can provide. 12/2/05--[[User:71.66.123.248|71.66.123.248]] <small>posted 00:33, December 3 2005 (UTC)</small>
Here are a couple of places to start where I found nice pictures of all the parts of red mapels: seeds, leaves, bark, etc. [http://www.uwsp.edu/cnr/leaf/treeid.htm] [http://dnr.wi.gov/org/land/forestry/treeid/index.htm] The habitat is where it is likely to be found in the wild, something like "northern temperate zone hardwood forest". Estimating the age from tree circumference can be done by finding a table of typical annual thickness increases for particular tree species [http://www.athensclarkecounty.com/documents/pdf/landscape_management/tcn_age.pdf] [http://www.uark.edu/misc/ents/threads/determing_age_of_street_trees.htm]. Or you can find a stump of a red maple, count the rings, and divide the radius by the number of rings to get the usual increase in diameter per year (remember diameter is twice radius). The circumference is about 3.14 x the diameter [http://www.mathgoodies.com/lessons/vol2/circumference.html]. Or you could call your state forestry service and ask if they can tell you how to do it. Good luck. [[User:Alteripse|alteripse]] 01:09, 3 December 2005 (UTC)
:I like "If you know when the tree was planted, you can easily and accurately determine its age." at [http://www.uwsp.edu/cnr/leaf/treeid.htm]. The list members at [http://www.uark.edu/misc/ents/threads/determing_age_of_street_trees.htm] apparently believe width is not a very good measure of age. I'm inclined to think alteripse's suggestion of contacting the state forestry service might be better. Your IP indicates you live in Virginia, so the phone number of the [http://www.dof.virginia.gov/website/contact-us.shtml Virginia Department of Forestry] is 434.977.6555 . If you don't, you can look it up. [[User:Superm401|Superm401]] | [[User_talk:Superm401|Talk]] 02:45, 3 December 2005 (UTC)
== Baby Tortoises ==
Esmé, a South African reader has sent the following question to the Wikimedia Help mailing list.
Please could you find out for me whether there is a specific term for a baby tortoise – so far the only term which has been presented is “baby tortoise” – surely there must be a more specific term?
I have advised her that it seems to be commonly used but I would be grateful if anyone could offer additional suggestions.
Thanks for any assistance you can give her.
[[User:Capitalistroadster|Capitalistroadster]] 02:04, 3 December 2005 (UTC)
:According to [http://dictionary.reference.com/writing/styleguide/animal.html dictionary.com] the baby [[turtle]] is called a [[hatchling]]. They don't have an entry for tortoises, but maybe that can be used for them as well? I expect it could be used for anything that hatches out of an egg. It does say what the collective noun for a group of tortoises is: a creep. I didn't know that, that's fun. -[[User:Lethe|lethe]] [[User talk:Lethe|<sup>talk</sup>]] 02:41, 3 December 2005 (UTC)
== UHF Radio Frequencies ==
Cecily, an Australian Wikipedia user has asked on the Wikipedia help mailing list.
I am buying a uhf radio to use to communicate while skiing. Can you tell me if I am able to use a pair of uhf radios bought in australia overseas. I am particularly interested to know if I can use them in Poland.
Also what about Canada and the USA. I believe they will work but is it illegal to use one that is on australian frequencies.
If you could help me with Poland I would be most grateful.
Thanks so much in anticipation
[[User:Capitalistroadster|Capitalistroadster]] 03:18, 3 December 2005 (UTC)
There are three zones for frequency allocations. In some regions those zones are divided across national borders. Generally, radios from one nation are only to be used there. An allocation in one nation for family talk UHF radios, could be used for Military communications elsewhere. [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 15:54, 3 December 2005 (UTC)
:So if I want to listen to military communications all I need to do is find out in which country those frequencies are used for domestic purposes and buy a radio there? Well, I suppose that if I were bent on that it might be easier to modify a radio to receive those frequencies. So the military won't be so stupid to use radio communication for 'classified' information. (Then again, ....) [[User:DirkvdM|DirkvdM]] 09:59, 4 December 2005 (UTC)
::No, but they may get pissed off if you start transmitting on their frequencies. If nothing else, it lowers their signal-to-noise ratio. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 23:53, 6 December 2005 (UTC)
== Salivary amalase? ==
Hello everyone! I am not sure if I recall this correctly, but I remember there is an enzyme in human saliva which helps with digesting glucose. The question I have is, if the time between chewing and swallowing is relatively short, what is the advantage of the body producing an enzyme which would only perform what seems to be a very very small part of digestion? --[[User:HappyCamper|HappyCamper]] 03:35, 3 December 2005 (UTC)
Salivary [[amylase]] begins the [[digestion]] of [[starch]] to [[glucose]]. Even a small amount of glucose will begin to trigger [[insulin]] release so that the insulin is rising as food is being digested. Salivary amylase is not necessary to digest starch but it helps amplify the speed of metabolic response, as well as providing a small burst of glucose as you begin to eat. Finally, conversion of even a small amount of starch to glucose in the mouth enhances the taste of carbohydrates in our mouths. [[User:Alteripse|alteripse]] 03:51, 3 December 2005 (UTC)
:Oh, I see...this sounds quite interesting...I didn't know that insulin is so sensitive to this. Would this be a reasonable example of a positive feedback system then? (From a controls perspective, "useful" positive feedback systems are almost unheard of, so it is excellent if this is considered one!) --[[User:HappyCamper|HappyCamper]] 03:54, 3 December 2005 (UTC)
::If you're looking for examples, [[oxytocin]] is a good one that occurs during labor. [[User:Daycd|David D.]] [[User talk:Daycd|(Talk)]] 03:58, 3 December 2005 (UTC)
:::I don't think salivary amylase is an example of positive feedback—where did you see the loop? Another biological example of positive feedback is during the menstrual cycle, such as the [[leutinizing hormone|LH]] surge. — [[User:Knowledge Seeker|Knowledge Seeker]] [[User talk:Knowledge Seeker|দ]] 04:22, 3 December 2005 (UTC)
::::As I understand it, the contribution of salivary [[Amylase|α-amylase]] (ptyalin) to overall starch hydrolysis is a relatively small fraction of overall carbyhydrate digestion; the lion's share of this task is performed by pancreatic amylase. Salivary amylase is rapidly inactivated by stomach acid, so its action is very brief. (By the way, the product of the action of salivary amylase on starch is maltose (a disaccharide), which would not be expected to directly stimulate insulin secretion). Salivary amylase is thought to take on a more important role in infancy, prior to the maturation of pancreatic exocrine function. It may also assume a bigger role in the adult in cases where pancreatic exocrine function is compromised. For a scholarly dissertation on the role of saliva in digestion, see: [http://tinyurl.com/7qkq6 Saliva and gastrointestinal functions of taste, mastication, swallowing and digestion] --<br /> Mark Bornfeld DDS<br/>[http://www.dentaltwins.com dentaltwins.com]<br/>Brooklyn, NY 05:30, 3 December 2005 (UTC)
I wouldn't characterize the insulin effect as positive feedback, but as early triggering or amplification of effect. Most food starch has a [[glycemic index]] almost as fast as glucose, indicating that hydrolysis of starch does not ordinarily contribute much to the time of absorption of many carbohydrates. There are a number of physiologic responses to the onset of eating that do not depend on waiting until substantial amounts of nutrients are already digested and absorbed and I suspect that the generation of a little glucose in the first minute of eating carbohydrates enhances some of metabolic and digestive responses as well as providing positive taste feedback to us. [[User:Alteripse|alteripse]] 12:54, 3 December 2005 (UTC)
== Atoms. ==
Hey, this is a bit of a hard question, and I looked but couldn't find what I was looking for. What are the chemical compounds/atomical mass/ect. of Blood, Bone, Skin, and Nail? Any help would be just wonderful, thank you.
~Ryan.
The chemical composition by element has been available for decades and is easy to find: [http://www.newton.dep.anl.gov/askasci/zoo00/zoo00432.htm]. The atomic masses of the elements you can easily look up. There is no list of all the molecules comprising blood, blone, skin, and nail because new ones are being continually discovered and it would run to the thousands. Of the four tissues you mentioned, nails are the simplest and are comprised mainly of a protein called keratin and water molecules but even the nails contain small amounts of many other things. As far as skin goes, you might just as well ask for a listing of every molecule in a human body. [[User:Alteripse|alteripse]] 12:36, 3 December 2005 (UTC)
== Nanobiotechnology ==
I have checked out the defination of nanobiotchnology from wikipedia, but I do not understand what it is saying. Can anyone please tell/explain to me what nanobiotechnology is really?
Thank you for your time.
[[Biotechnology]] on very small scales. --[[User:YixilTesiphon|YixilTesiphon]] 13:32, 3 December 2005 (UTC)
For example the use of tiny [[biosensors]] that can be implanted under the skin and monitor things like blood glucose level. These use an [[enzyme]] to break down the glucose, a biological recognition layer to record the amounts of the products of the enzyme-substrate interaction, and a [[transducer]] to convert this into an electrical signal - very clever really! --Unregistered user 18:07 3 December 2005
Try [[Nanomedicine]] and the links in that article. --[[User:JWSchmidt|JWSchmidt]] 01:49, 4 December 2005 (UTC)
== Library digitization ==
I am not sure that I understand the extent of this process, digitizing library collections. Is it simply creating a digital catalog, or the larger process of scanning documents and entering data?
Thanks so much for clarification.
*Usually, it's scanning entire books. (I'm assuming you're referring to projects such as Google Book Search.) Some library whose name I can't remember in Egypt which has a large collection of rare [[Islam|Islamic]] texts recently scanned its entire collection. --[[User:YixilTesiphon|YixilTesiphon]] 15:37, 3 December 2005 (UTC)
== how long did people need totrain with weights to lower their risk of coronary heart disease by 23%? ==
The question is like above. I searched but they couldnt find anything. So here goes, how long did people need totrain with weights to lower their risk of coronary heart disease by 23%? A) 30 minutes b)55 mins c)80 minutes
Second one,
After what age would people startlosing muscle mass & strength caused by hormonal changes? A)30 b)40 c)50
I need it to be very accurate. BTW, thanks to everyone who helps me with the question. Many thanks ppl.
The precision of the desired answer tells me the answer was produced by a specific research study which you were supposed to read. How do you expect us to know which study that was? [[User:Alteripse|alteripse]] 18:25, 3 December 2005 (UTC)
*Please do your own homework. General questions are cool and interesting. Specific ones taken off the worksheet due Monday aren't. --[[User:YixilTesiphon|YixilTesiphon]] [[User talk:YixilTesiphon|Say hello]] 18:32, 3 December 2005 (UTC)
== Ubuntu live cd ==
I was trying to run the 5.10 live cd on my older PIII 800 Mhz 128MB RAM Dell Inspiron 2500, but it is glacially slow. I'm assuming it's because 128MB is not enough to run with all the default software the live cd has on it, but it's so slow (10min to open a terminal window) that I can't even kill processes to free up memory. Is there an easy way to get the 5.10 live cd to use a file on the windows partition as swap? Or do I just have to wait till I get a terminal window and set up a swapfile manually? (Which I'll have to go search to remind myself how to do that again.) Thanks - [[User:Taxman|Taxman]] <sup><small>[[User talk:Taxman|Talk]]</small></sup> 15:53, 3 December 2005 (UTC)
: If you are using windows xp, your windows partition is probably a [NTFS] partition, which ubuntu/linux cannot write to, only read it. If you have a fat32 partition, I don't know, it might be possible. --[[User:Wouterstomp|WS]] 01:35, 5 December 2005 (UTC)
:::XP on a machine of those specs? Surely you jest. No it was ME, but I decided to just bite the bullet and install, and it worked out all for the better. Everything works amazingly well including the sound, power management, and wireless. I'm assuming the winmodem won't but oh well. It's still slow, so I'm planning to figure out how to slim it down a lot. I guess the first step would be a lighter window manager. I'll try to haunt some Ubuntu forums and learn the ropes, but if anyone has some info on good ways to slim down the ram requirements, I'd be interested. - [[User:Taxman|Taxman]] <sup><small>[[User talk:Taxman|Talk]]</small></sup> 14:23, 5 December 2005 (UTC)
::It's difficult to configure Linux distros on Live CDs to access the hard disk for its swap files. Alternatively, you could use [[Damn Small Linux]], which is only 50 MB in total, but fits a [[GUI]] and a surprising number of programs onto it. Surely 50 MB can fit into 128 MB of RAM. :) -- [[User:Daverocks|Daverocks]] 11:25, 5 December 2005 (UTC)
:::Well I had an older DSL disk, but I couldn't get it to boot properly, the 2.4 kernel would hang at some point. And with the compression those livecd's use 50 MB could be made to overwhelm 128MB of RAM too :) - [[User:Taxman|Taxman]] <sup><small>[[User talk:Taxman|Talk]]</small></sup> 14:23, 5 December 2005 (UTC)
== climate change/global warming ==
what is the difference between global warming and climate change? why did the media, which used to call it global warming, suddenly all start calling it climate change in unison? who made them change? {{unsigned|Zzzzz}}
:Global warming now has a paranoid stigma about it. It's merely a form of climate change; the other would be global cooling. --[[User:YixilTesiphon|YixilTesiphon]] [[User talk:YixilTesiphon|Say hello]] 16:06, 3 December 2005 (UTC)
:Have a look at [[Global warming]] and [[Climate change]]; basically climate change describes the broader phenomenon which includes not only the current anthropgenic warming but other fluctuations such as past glaciation, etc. In addition, while warming is the major phenomenon, other things like altered rainfall regimes are also part of the picture. [[User:Guettarda|Guettarda]] 16:14, 3 December 2005 (UTC)
::I'd say that last bit is probably the most important. Global warming is just one aspect and it's arguably not even the worst. And to a layman (especially one living in a moderate or cold climate) it might even sound like a good thing. Also, warming is the most likely effect. Other theories say we could be creating a new ice age. So calling it warming is a premature conlusion. That there will be a (major) climate change is however beyond doubt by now. Finally, with ''global'' warming you may still get ''local'' cooling. [[User:DirkvdM|DirkvdM]] 10:07, 4 December 2005 (UTC)
== astronauts ==
Could kindlygive the list of astronuts with their nationality, date and year who have landed on moon till 2005
*Try searching [http://www.nasa.gov NASA.gov] or look up the [[Apollo program|Apollo missions]] here. --[[User:YixilTesiphon|YixilTesiphon]] [[User talk:YixilTesiphon|Say hello]] 18:20, 3 December 2005 (UTC)
*All the astronauts who landed on the moon were Americans and did so between July 1969 and about 1974. [[User:Alteripse|alteripse]] 18:23, 3 December 2005 (UTC)
*They were also all men, but for political purposes, our [[list of men who walked on the Moon]] has been moved to [[list of lunar astronauts]]. - [[User:Nunh-huh|Nunh-huh]] 18:37, 3 December 2005 (UTC)
**Maybe the move was future-proofing, not political.--[[User:Commander Keane|Commander Keane]] 22:01, 3 December 2005 (UTC)
***As future-proofing, it hardly seems urgent. But that doesn't make it political either; I think we all agree that the list would include women if there were any, so the astronauts' sex is not relevant to their inclusion and doesn't need to be mentioned in the title. --[[User:Trovatore|Trovatore]] 22:57, 3 December 2005 (UTC)
**The article includes the 12 Apollo astronauts who went near the moon but did not land as well as the 12 who did land, so in any case the "walked on the moon" part would be wrong. --Anon, 07:52 UTC, December 4, 2005
***Nunh-huh is probably talking about [http://en.wikipedia.org/w/index.php?title=List_of_men_who_walked_on_the_moon&oldid=1487602 this article]. A little hard to find, because the link he gave was capitalized differently. It wasn't actually ''moved''; it was ''redirected'' as a duplicate article. --[[User:Trovatore|Trovatore]] 08:00, 4 December 2005 (UTC)
==photon mass==
No one's responded to this question on [[Talk:Photon]], so I thought I'd ask here.
What is the status of the possibility that photons have nonzero rest mass? I remember seeing an old ''Scientific American'' article on it, showing how [[Maxwell's equations]] would have to change, among other things. As I understand it, current observations have put an upper bound on photon rest mass, but have not ruled out its existence. However, supposedly (I don't understand why), the discovery of a [[magnetic monopole]] would refute a nonzero rest mass for photons.
Anyone know anything about this? Have there been any theoretical or experimental developments that bear on the question since the article I remember (which probably would have been from the '70s or so)? --[[User:Trovatore|Trovatore]] 19:37, 3 December 2005 (UTC)
:It is impossible, in some sense, to rule out the photon mass. But there are upper limits, set by experiments where we'd ''see'' the changes to Maxwell's equations if it had a mass above some value. At current, the recognized upper bound on the photon mass is
::<math>6 \times 10^{-17}</math> [[electron volt|eV]] [http://pdg.lbl.gov/2005/listings/s000.pdf]
:Or about 0.0000000000000000001 times the mass of the [[electron]], the lightest particle whose mass is known. I don't know anything about magnetic monopoles ruling out photon masses, but it is the sort of strange thing that finding magnetic monopoles would do—they also explain charge quantization, which I saw a proof of once but have since forgotten. Well, that's a start at least. -- [[User:SCZenz|SCZenz]] 19:46, 3 December 2005 (UTC)
::Thanks. Might make an interesting note in [[Photon]]. --[[User:Trovatore|Trovatore]] 20:00, 3 December 2005 (UTC
*The mass of photons is also often measured in terms of their energy in Mega-[[Electronvolt|electronVolts]] (using the equation E=mc<sup>2</sup>) --[[User:YixilTesiphon|YixilTesiphon]] [[User talk:YixilTesiphon|Say hello]] 21:06, 3 December 2005 (UTC)
**I specified in the question that I was asking about ''rest'' mass. You're talking about "relativistic mass". --[[User:Trovatore|Trovatore]] 21:09, 3 December 2005 (UTC)
***Well, that's what I get for skimming. Sorry. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> 21:32, 3 December 2005 (UTC)
** Anyway, particle physicists don't refer to "photon mass" in this manner, since by [[E=mc²]] it would be completely redundant with the energy. Photons that are internal lines in [[Feynman diagram]]s can have non-zero mass (which can't be directly observed), but this is completely different. -- [[User:SCZenz|SCZenz]] 23:29, 3 December 2005 (UTC)
I don't think a monopole would refute a nonzero mass of the photon. It would probably depend on what kind of mass it was. For example, if the photon mass were due to a Higgs mechanism, monopoles would still be allowed. As for whether monopoles are allowed in the Proca equation, or if the mass is from a topological term, I'm not sure. -[[User:Lethe|lethe]] [[User talk:Lethe|<sup>talk</sup>]] 23:22, 3 December 2005 (UTC)
"Or about 0.0000000000000000001 times the mass of the electron, the lightest particle whose mass is known. I don't know anything about magnetic monopoles ruling out photon masses, but it is the sort of strange thing that finding magnetic monopoles would do—they also explain charge quantization, which I saw a proof of once but have since forgotten. Well, that's a start at least. -- SCZenz 19:46, 3 December 2005 (UTC)"
With that being said, photons would have to have infinite inertia, according to GR. Photons travel at C, and any mass would have infinite inertia at C. Do photons have infinite inertia?
:If photons have positive rest mass, then they ''don't'' travel at ''c'', but rather at different speeds depending on their energy. Since no such speed difference has ever been observed in vacuo (or at least I assume I'd have heard about it if it had been observed), the experimental error of these observations provides one way of putting an upper bound on their rest mass. --[[User:Trovatore|Trovatore]] 20:12, 6 December 2005 (UTC)
:"A fast-moving object moving at near to the speed of light cannot be accelerated to, or faster than, the speed of light, regardless of how much energy we put into the system. As we apply a force, and hence do work on the object, its speed does not appear to increase by the amount specified by Ekinetic = 1/2 mv2. Instead, the energy provided to it is converted to mass, and its relativistic mass increases, in what is known as mass dilation. The relativistic mass of an object is expressed as a function of its relative speed." If a particle has any mass at all, at rest or in motion, it's inertia would be infinite if it were to travel at C. Photons do not have infinite inertia. You can keep reminding me of the bandaid Einstein used to keep GR together, but every attempt you make will only reinforce my argument against it. Rather than have me show you proof of photons not existing, why don't you offer definitive proof of photons existing. You cannot, without "funneling" light waves through a lens or aperture. It is because in every conceivable method of detecting a "photon" you must use a lens or aperture, which "focuses" the wave into a point, (be it in your eye, or in a camera). For this reason, and because it holds GR together, do people assume they exist. Kevin E Carman
== Running Processes ==
I run Windows XP, and I always have a lot of processes running. Right now, for example, I have 54, and I think that's low for today. Some I recognize (such as firefox.exe, or WINWORD.exe), but others I do not. Is there a program I can get, or a website to which I could refer, that would help me eliminate some of the extra ones I'm sure I'm running? Thanks! --[[User:ParkerHiggins|ParkerHiggins]] 20:26, 3 December 2005 (UTC)
:Just copy the process name into Google. You will quickly find many sites discussing each process. Windows XP has MANY programs that run in the background. It isn't like Windows 98 where you could safely kill everything except systray and explorer. As you find out what is running, you may find services running you don't want (like wireless network detector, pcmcia monitor, or firewire support). You can disable those services in the control panel somewhere. I don't remember exactly where. I gave up on Windows a couple years ago. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 02:09, 4 December 2005 (UTC)
:One place is in Control Panel > Administrative Tools > Services. In the right hand pane will be a list of services, their names, a long description, and whether they're started or not. [[User:Antifamilymang|George]] 03:32, 4 December 2005 (UTC)
:To turn off running processes, go to "Run..." in the start menu. Then type in "msconfig". This should bring up a window titled "System Configuration Utility". Click on the "Startup" tab. There should be a list of processes there that you can check or uncheck to startup with windows. Hope that helps!--[[User:Dimblethum|Dimblethum]] 05:12, 4 December 2005 (UTC)
== DVD X ==
The Wikipedia Help mailing list received an inquiry from a reader as follows.
I bought DVD X copy program the last day they could sell them at Best Buy and when I went to activate it they said it was not longer allowed to activate the programs so I was out $119.00 and left with a program that I could not use I would really like to know if there is anything that I can do I guess this is what happens when you are computer stupid. My license ID:2641969 and I also have a pass word for it but need an activation key for it
If you can help this reader, it would be greatly appreciated. [[User:Capitalistroadster|Capitalistroadster]] 22:59, 3 December 2005 (UTC)
:From the DVD X website... "CAUTION: Authentic DVD X Copy software is no longer being sold anywhere. Many "closeout", clearance, auction and discount websites are selling fake DVD X Copy Software products and "patches" that are not authentic, CANNOT be activated or are cracked versions that DO NOT WORK properly and/or that contain spyware. Beware of any sites that continue to sell version 4.0.3.8 and that guarantee activation. DVD X Copy products purchased from these sites are not authentic, not eligible for support or updates and should be returned for a refund." --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 02:05, 4 December 2005 (UTC)
== HFS command line utilities ==
I can't remember what are the command line utilities for changing the locked status of files under Mac OS X on an HFS plus volume. -[[User:Lethe|lethe]] [[User talk:Lethe|<sup>talk</sup>]] 23:04, 3 December 2005 (UTC)
:Found the answer. /Developer/Tools/SetFile -[[User:Lethe|lethe]] [[User talk:Lethe|<sup>talk</sup>]] 01:47, 4 December 2005 (UTC)
=December 4=
== penguins ==
When a penguin swims vs. walks, they have different heart rates due to a different intake of oxygen.
When it swims, it needs more oxygen right?
Is there any new information(from the past 3 years) on this topic, so i can base my essay on that?
Thanks alot
:Your assumption is most likely incorrect. While I am not a penguin expert, semi-aquatic animals have a slower heartrate in water than on land. A quick google search confirms the same for penguins [http://www.edhelper.com/penguin_wordproblems52.htm]. The issue is oxygen use. Penguins don't want to consume more oxygen while swimming - they want to consume less. So, over time, penguins who have slower heartrates while swimming are able to swim longer and deeper and get more fish. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 02:03, 4 December 2005 (UTC)
::Though penguins aren't mammals, they might have something like the [[mammalian diving reflex]]. Is there an "avian diving reflex"? —[[User:Keenan Pepper|Keenan Pepper]] 03:43, 4 December 2005 (UTC)
:::I was only assuming that penguins would have a similar reflex to mammals. As for the avian diving reflex, according to Ponganis (I don't know who he is), many avian species have diving aerobic activity that exceeds the calculated diving aerobic limit - requiring a slowed use of oxygen during diving. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10936756&dopt=Abstract] --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 04:20, 4 December 2005 (UTC)
:One comsideration. You probably mean oxygen consumption in time. But a swimming penguin is of course much faster than a walking one (what, twenty times faster or so? - 1 km/h vs 20 km/h). So the consumption per distance (ie the efficiency) will be much higher when swimming. [[User:DirkvdM|DirkvdM]] 10:21, 4 December 2005 (UTC)
::(Dirkvdm means consumption per distance will be ''less'', and efficiency would be more, as it could be considered the reciprocal.) --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> 13:08, 4 December 2005 (UTC)
:::Oops. [[User:DirkvdM|DirkvdM]] 10:22, 5 December 2005 (UTC)
One of your problems is that you haven't justified your ''assumption'' that penguins need more oxygen while swimming than while walking/waddling: if I were forced to walk like a penguin, then allowed to swim naturally, I think I would find the latter less tiring... Another, more complex point is to look at thermal regulation in penguins: in which environment is their overall heat loss the greatest? Finally, if you're still stuck, consider the oxygen equilibrium in large aquatic mammals (e.g., whales): this won't give you the answer, but it will at least convince you that the answer is out there somewhere! [[User:Physchim62|Physchim62]] [[User talk:Physchim62|(talk)]] 13:15, 4 December 2005 (UTC)
== Wiki administration ==
The Wikimedia help desk received the following question from Carey, a Wiki administrator.
I am wanting to do a little administration on the Wiki I installed internally but I didn't see anything concerning my idea. I want to limit a specific user or group to only be able to edit specific pages and their contents. Basically this user is going to be updating one specific page but I don't want that user to be able to edit any other pages.
I know there is a protect option to protect pages but my current Wiki has several thousand pages and protecting each one would be very time consuming not to mention not a suitable solution. If anyone knows of a way or if this isn't possible, I would like to know. Thanks in advance!
Thank you for any assistance you can give him. [[User:Capitalistroadster|Capitalistroadster]] 02:21, 4 December 2005 (UTC)
:Seems like [[mail:MediaWiki-l|MediaWiki-l]] would be the right place for this question (see [[Wikipedia:Mailing lists]]). -- [[user:Rick Block|Rick Block]] <small>([[user talk:Rick Block|talk]])</small> 17:40, 4 December 2005 (UTC)
== Two dimensional molecule structure database ==
Can you guys help me find a good and reliable databases that features 2 dimensional molecular structures? An example of a 2 dimensional structure would be the image in the [[Adenosine monophosphate|AMP]] article. I've found some databases on 3-dimensional structures of proteins [http://cathwww.biochem.ucl.ac.uk/latest/index.html], but am having a harder time finding something similar for 2 dimensional structures. [[User:KBi|KBi]] 03:31, 4 December 2005 (UTC)
* The {{nist}} will probably not always have the structure you're looking for, but it is not bad. Otherwise there is [http://chemfinder.cambridgesoft.com/ ChemFinder], or [[PubMed]], or several others depending on the compound you're looking for (Google as a last resort, but it '''can''' be useful for this type of problem)... A little bit more details about the type of compounds you're interested in would help to answer your question more specifically. [[User:Physchim62|Physchim62]] [[User talk:Physchim62|(talk)]] 13:23, 4 December 2005 (UTC)
== To calculate Heat dissipation ==
Could you please forward the formulae, which will be used to calculate Heat dissipation?
For example, if a equipment power consumption is 200 watts, how much will be heat dissipation value from that equipment? How to calculate?
Thanks in advance.
C.Ramesh
Sulaiman Petrotech ME FZE
Innovative Engineering Solutions
P.O.Box.: 18326.
Jebel Ali.
Dubai, U.A.E.
Tel: 00971 4 8833525.
Fax: 0097 1 4 8833626
Email: ([[Email spam|Email removed]])
:Heat dissipation ≤ power consumption (in non-combustion situations). ''See'' [[First law of thermodynamics]]. [[User:Physchim62|Physchim62]] [[User talk:Physchim62|(talk)]] 13:26, 4 December 2005 (UTC)
: I suggest getting an engineering textbook. For example, Coulson & Richardson's Chemical Engineering, Volume 1: Fluid flow, Heat transfer and Mass transfer. There is no simple formula, except for heat transfer through radiation ([[Stefan-Boltzmann law]]). For non-radiative heat transfer (convection), you've get a lot more work to do. And the subject can't really be covered properly in anything smaller than a book. (And there are quite a few available) --[[User:BluePlatypus|BluePlatypus]] 23:52, 4 December 2005 (UTC)
If the system consumes 200W in power, unless it comes out in another form, almost all of it is heat. If a mythical board in a 10V system draws 20A, and has an output that sends a signal with 200Vrms and 1A almost no heat would be converted. ALmost all computers make heat from all the power they consume. Now a 200W powersupply does not always generate 200W, but has a maximum rating of 200W.[[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 15:51, 6 December 2005 (UTC)
== Optics of reading a CD ==
I've been looking for information on how a CD is produced and read. In particular I am interested in the optics involved in reading the CD. Can anyone refer me to a source that discusses exactly what the interference is that reduces the light reflected at a pit-land boundary? Is it reflections from the two surfaces on either side of the boundary?
The article at http://en.wikipedia.org/wiki/Compact_disc contains a wealth of information, but there is one portion that bothers me. In the 4th paragraph under "Physical details" it is stated that the 125 nm pit depth is about one-sixth of 780 nm wavelength of the laser, and then "The sixth, 125 nm, (and not a quarter) of the wavelength was chosen to have a good trade-off between the push-pull radial tracking signal and the full-aperture read-out signal."
The relevant wavelength has to be that in the bottom polycarbonate layer. The pit depth would be one-fourth of the wavelength in the material for a refractive index of 1.56, close to what I find (1.55 to 1.58) listed in various places, so this is consistent. This raises a question about the rest of that sentance regarding tracking. I am seeking info on the subjest, and am not comfortable editing the article at this time. Apologies if I've violated any protocals here. --[[User:StanH|StanH]] 06:22, 4 December 2005 (UTC)
*You're right. That change (from one quarter to one sixth) was made by user [[User:Dsc|Dsc]] a short while ago. It appears to be purely wrong, perhaps he doesn't understand how wavelength is reduced in a medium, and assumed a reason for it. The rest of the info would seem to be suspect. --[[User:DrBob|Bob Mellish]] 06:39, 4 December 2005 (UTC)
== what is SIP Protocol ==
Dear Sir,
Could you plz let me know the meaning of the sentence"Voice Gateway on SIP Protocoland and all are line port"?
My question...........
1)what is SIP Protocol?How it works?How it is related with Voice Gateway?
2)What is Line Port?
*SIP is [[Session Initiation Protocol]]. See the article for how it works.
*On the back of your [[Voice over IP]] equipment, there should be two ports: LINE and PHONE. The line port should be connected to the phone line, and if you have a phone handset, that can be connected to the phone port.
--[[User:Canley|Canley]] 12:30, 4 December 2005 (UTC)
== comperision ==
which are the coolest materials from the following list. Arrange in order.
No insulation
wool
felt
cotton
bubble wrap
'''Do your own homework''' Cool is a subjective term. [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 12:22, 4 December 2005 (UTC)
:I think bubble wrap is the coolest, because the bubbles are so fun to pop. —[[User:Keenan Pepper|Keenan Pepper]] 16:03, 4 December 2005 (UTC)
:Really? I say "No" is. That stuff is amazing - you can hardly feel it! --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 16:49, 4 December 2005 (UTC)
:Well I am not into "wrap". [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 20:57, 4 December 2005 (UTC)
::Here is my order, from worst to best: wrap, insulation, felt, cotton, wool, bubble, no. — [[User:Knowledge Seeker|Knowledge Seeker]] [[User talk:Knowledge Seeker|দ]] 02:39, 5 December 2005 (UTC)
==(Header for the following question added)==
how does the 25 elements of the body works? {{unsigned|203.160.177.26}}
*See [[biochemistry]] --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 15:15, 4 December 2005 (UTC)
== sperm color ==
what color is sperm suppose to be? {{unsigned|134.215.216.119}}
*I'm assuming you're referring to [[semen]]. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 14:34, 4 December 2005 (UTC)
*White. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 09:38, 5 December 2005 (UTC)
:Lol, interesting question. Usually it is white, but, from what I've heard, it can be yellowish, grayish, or brownish and still be fine.[[User:Dimblethum|Dimblethum]] 04:46, 6 December 2005 (UTC)
== science ==
[[Thomas Dolby]]!!!!! [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 20:55, 4 December 2005 (UTC)
== What mammals name's begin with x? ==
(no futher question)
Visiting [[:Category:Mammals]] I came up with [[Xenarthra]]. Can't say I've ever seen one of those at the local park.--[[User:Commander Keane|Commander Keane]] 19:06, 4 December 2005 (UTC)
:Xenarthra are things like [[sloths]] and [[armadillos]]. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 21:30, 4 December 2005 (UTC)
Checking my OED, I find no mammals listed (other than blond humans, and the order Xenarthra mentioned above) beginning with X. [[User:Crypticfirefly|Crypticfirefly]] 06:22, 7 December 2005 (UTC)
== Omega-3 fatty acids ==
What are the best sources of Omega-3 fatty acids?
: oily fish like salmon is one, please sign your edits using four tilde(~) keys thanks [[User:7121989|7121989]] 19:37, 4 December 2005 (UTC)
:See [[Omega-3 fatty acid]], and notice there is a fair amount of dispute over whether they are the greatest diet discovery since bread or relatively minor. Do some research and decide for yourself. - [[User:Taxman|Taxman]] <sup><small>[[User talk:Taxman|Talk]]</small></sup> 14:29, 5 December 2005 (UTC)
== Gaia ==
# How much of the [[insolation]] is available [[energy]] for the [[biosphere]]?
# Should this be a proportion roughly equal to the [[energy conversion]] efficiency of [[chlorophyll]], after accounting for land area?
## How efficient is chlorophyll, anyway?
# How much energy does the biosphere actually use?
{{User:Eequor/Signature/Syllabic}} 20:44, 4 December 2005 (UTC)
:The answer to point 3 is suggested by [http://www.fao.org/docrep/w7241e/w7241e05.htm this UN report]: "photosynthetic energy capture is estimated to be [[1 E19 J|ten times]] that of global annual energy consumption". The latter was [[1 E18 J|3.8×10{{sup|15}}]] [[BTU]] in 1999 according to [http://www.solarbuzz.com/FastFactsIndustry.htm US DOE EIA]. The UN report also calculates the efficiency of photosynthesis to be between 3% and 6%. --[[User:Heron|Heron]] 21:35, 4 December 2005 (UTC)
:: Interesting... oughtn't that be [[1 E20 J|3.8×10{{sup|17}}]] BTU, though? {{User:Eequor/Signature/Syllabic}} 22:21, 4 December 2005 (UTC)
...This seems to show that the insolation, [[1 E17 W|1.74×10{{sup|17}}]] W, is four to five [[orders of magnitude]] greater than the biosphere can make use of ([[1 E12 W|3.6-7.2×10{{sup|12}}]] W). Is that right? {{User:Eequor/Signature/Syllabic}} 22:37, 4 December 2005 (UTC)
<ol><li value="4">
Given that even the internal heat flux of the Earth is about an order of magnitude greater than the photosynthetic output, is the [[homeostasis]] [[Gaia hypothesis]] effectively impossible? {{User:Eequor/Signature/Syllabic}} 23:13, 4 December 2005 (UTC)
</li></ol>
:Photosynthesis is not the only variable that is under the influence of living organisms. The composition of the atmosphere can be altered by living organisms, changing the ratio of energy entering and leaving the biosphere. --[[User:JWSchmidt|JWSchmidt]] 02:53, 5 December 2005 (UTC)
::In fact, practically every characteristic of the Earth that I can think of, except its magnetism, can be altered by living organisms. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 03:48, 5 December 2005 (UTC)
::: Yes; very generally, I'm curious whether the relatively small amount of energy available to the biosphere is enough to control global energy variations to a significant degree. I suppose altering Earth's [[chemistry]] is probably the easiest method. {{User:Eequor/Signature/Syllabic}} 04:27, 5 December 2005 (UTC)
== Hot water freezes faster than cold? ==
I was watching a tv programme recently that performed an experiment where room temperature and near boiling water was placed in different ice cube trays, when placed in a freezer, x minutes later the hot water had frozen faster than the cold water. I've yet to try this so don't know if this is true, but if it is, why would this be the case? I can't think of any logical reason why this would happen, so i'm wondering if anyone else knows why? Thanks in advance [[User:84.64.138.234|84.64.138.234]] 22:00, 4 December 2005 (UTC)
*See [[Mpemba effect]]. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 22:08, 4 December 2005 (UTC)
*[http://www.straightdope.com/classics/a2_098b.html The Straight Dope] also has some info on the subject. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 09:47, 5 December 2005 (UTC)
== Too-wide tables in LaTeX ==
I've made a table in my LaTeX document that's narrower than the page, but wider than the page margins. LaTeX keeps aligning it with the left margin instead of centering it horizontally on the page. How can I get the table centered horizontally? I'm using the "tabular" environment at the moment. Thanks. -- [[User:Creidieki|Creidieki]] 23:49, 4 December 2005 (UTC)
:Have you tried resizing the table to the margin size or less?
\resizebox{!}{17cm}{\begin{tabular} ... \end{tabular}}
:--[[User:Canley|Canley]] 01:59, 5 December 2005 (UTC)
=December 5=
==Tunneling==
Dear Help Desk
There is a new construction tunneling method is called New Austrian Tunneling method which we have read it from your website we are going to do a research program on this subject. This method is based on using a single lining of sprayed concrete using HPP fibres. Could you please advise me if there is some paper published about this method and how we can reach to any projects details using this method.
With Best regard
Dr Hamid Abbasi (FRPRC)
*Check the "Internal links" section of the article you're referring to. If there's nothing there, click on the "history" tab above the article, and scroll down to the creator of the article. Click on his/her name, then click on the "talk" tab above his userpage, then click on the "+" tab to leave him/her a message. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 22:26, 5 December 2005 (UTC)
== Do bluetooth phones have SAR ratings? ==
Bluetooth techology sounds like a good way to increase distance between my head and the phone thereby making them safer choices.
Questions...
What type of "waves" do the ear pieces give off?
Is there a SAR for these waves, like there are for Dig/Analog phones
What is considered an acceptable (i.e., safe) level of emission?
Is bluetooth any safer than regular dig/analog cell phones from a emission stand point?
Thank you.
[[User:Crillion|Crillion]] 11:42, 5 December 2005 (UTC)
:[http://www.businessweek.com/technology/content/apr2005/tc20050427_5651.htm This article] in BusinessWeek might be of interest. –[[User:Mysid|Mysid]] 11:56, 5 December 2005 (UTC)
== How to make a good flint for lighter? ==
A flint is composed of mischmetal, iron oxide and magnesium oxide. However, why is German flint much better than the Chinese flint? What are the differences? Does the purity of mischmetal make the difference? Or, the process of making the flint matters? Please kindly answer my questions, or kindly provide any references to me. Thank you very much.
:While you are awaitng the definitive answer, take a look at [[Ferrocerium]].--[[User:Commander Keane|Commander Keane]] 16:30, 5 December 2005 (UTC)
== Cost of leaving a computer monitor on ==
In a standard 9-5 work environment, what is the annual cost in wasted energy of leaving a PC monitor switched on overnight and at weekends, if the PC itself is switched off at those times (so the monitor will be in standby mode, not displaying anything)? Assume a fairly standard 15" CRT monitor, and UK energy prices. I'm trying to convince my work colleagues that this is worth bothering with (I work for a charity and saving money is important), but they all think that the cost is utterly negligible. I've tried Googling but couldn't find anything that quantified it in hard cash, though others may have more luck with different searches. --[[User:194.73.130.132|194.73.130.132]] 16:19, 5 December 2005 (UTC)
*A search for "monitor power consumption" comes up with useful information. For example, this 15" [http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-4Q9HJX IBM monitor] eats 70 watts when its in regular use, and 10 watts in standby -- and 5 watts in "VESA off", which I imagine is how things would be with the computer turned all the way off. Using this UK [http://www.ukpower.co.uk/running-costs-elec.asp power cost calculator]: assume, then, 128 hours standby per week, ~512 hours standby per month will run you £0.14 -- about the equivalent of leaving a 100-watt lightbulb on for a day. Wasting any energy, of course, is not a good thing, but you won't be able to make a hard cash argument for it. --[[User:Jpgordon|jpgordon]][[User talk:Jpgordon|∇∆∇∆]] 16:39, 5 December 2005 (UTC)
:*And it seems to vary by monitor make/model/age; my Optiquest Q71 (a 17" CRT) claims less that 3 W consumption in standby/powersaving mode. The [http://www.energystar.gov/index.cfm?c=computers.pr_crit_computers Energystar] specs may prove helpful. --[[User:DrBob|Bob Mellish]] 18:47, 5 December 2005 (UTC)
::We have several posters at work that say that leaving a <nowiki>[</nowiki>[[cathode ray tube|CRT]]<nowiki>]</nowiki> monitor on overnight wastes enough energy to laser print 800 [[A4 paper|A4]] pages. How accurate this is (or indeed how much energy it acutally is) I don't know, but I would suspect it is a useful [[rule of thumb]]. [[User:Thryduulf|Thryduulf]] 01:51, 6 December 2005 (UTC)
:::I would expect a printer running for that long to use a lot more energy than a CRT monitor left on at night, but that might just be reflection of my ignorance. -04:27, 6 December 2005 (UTC)
:5 Watt over 1 year is 5 x 24 x 365 = roughly 40 kWh. A 200 horsepower car engine delivers 147 kW. So the yearly power consumption of one monitor would let a car engine run for less than 20 minutes (is this correct?). Convincing ''one'' colleague who lives nearby, but commutes by car, to go to work by bicycle (or a more distant one by public transport) just ''one day per year'' would have a similar, if not bigger, effect. The goodie bit about this is that you can do it yourself (providing you don't already), so you don't need to convince anyone. And you could even do it every day. Wow, think of the effect that would have! And ''then'' you could also try to convince your colleagues to follow ''that'' example. In other words, consider barking up the right tree :) .
::I would love to commute by public transport, but 2-3 hours on three busses with a 5-10 minute walk each end vs 50 mins-1 hour door to door by car is no contest unfortunately. [[User:Thryduulf|Thryduulf]] 11:49, 6 December 2005 (UTC)
:::Gah, public transport must be awful where you live... ''checks userpage'' Oh. The UK. Right, just what I said... ;) [[Image:European-Austrian flag hybrid.svg|20px]] [[User:Nightstallion|ナイトスタリオン]] [[User_talk:Nightstallion|✉]] 12:08, 6 December 2005 (UTC)
:Which makes me think. Shouldn't we have an article that lists the power consumption of different household items and such (and the power cost of making them). I bet the car would be at the top of the list in a very isolated position. I've searched for 'power consumption', which didn't give any results. And [[ecological footprint]] doesn't help either. [[User:DirkvdM|DirkvdM]] 11:29, 6 December 2005 (UTC)
::As long as the information is verifiable, I think that would make a good article and/or list. [[User:Thryduulf|Thryduulf]] 11:49, 6 December 2005 (UTC)
== Weakened virus ==
The [[virus]] article states that vaccination is "''the process of administering live, albeit weakened, microbes''", though it also states that the cowpox virus is "''a relatively benign virus that, in its weakened form, provides a degree of immunity to smallpox''"
Firstly, obviously these sentences seem to contadict eachother. Is the virus weakened, or are the microbes containing them?
Secondly, how would one go about in weakening a virus? Is is irradiated, denaturated, shaken, ..? -- [[User:Ec5618|Ec5618]] 17:02, 5 December 2005 (UTC)
:In the context of the source article, the term "microbe" refers to the microscopic causative disease agent-- in this case, the virus. It does not refer to some host organism (although there are bacteria, which are microbes, that are parasitized by viruses, which are also microbes). Smallpox vaccine is actually live vaccinia, or cowpox virus, and is not an attenuated virus. It is, however, sufficiently antigenically similar to smallpox that a cowpox infection (the intent of administering the vaccine) will confer protective immunity in a person who is immunologically competent. There are (other) vaccines that are live attenuated virus vaccines, such as the Sabin polio or the FluMist influenza vaccines, in which the virus is alive but modified so that it does not cause a full clinical infection.
:Viruses are sometimes attenuated by culturing them in an environment that is different from the that found in the intended recipient of the vaccine. For example, a virus is cultured in a progressively colder environment, which selectively favors successive generations of the virus that are adapted to an environment that is below body temperature. These viruses would presumably find normal physiologic body temperature to be inhospitable, but would survive long enough to cause a mild infection and provoke an immune response. Denaturation of viruses usually results in a killed virus vaccine. --<br /> Mark Bornfeld DDS<br/>[http://www.dentaltwins.com dentaltwins.com]<br/>Brooklyn, NY 18:04, 5 December 2005 (UTC)
::[[Vaccinia|Vaccinia virus]] has diverged from cowpox virus; they are now distinct viruses. See [http://www.stanford.edu/group/virus/pox/history.html this history] which is cited at [[Cowpox]] and [http://vir.sgmjournals.org/cgi/reprint/85/1/105.pdf this analysis]] which is cited at [[Vaccinia]]. --[[User:JWSchmidt|JWSchmidt]] 03:28, 6 December 2005 (UTC)
== Xu bird ==
Is there such a bird in china as the Xu? I find mention of it in two articles by the same anonymous user ([[nullaby]] and [[orange flavor chicken]]) and I can't decide if he or she is just making it up. I've googled it as thoroughly as I can and find no mention of it, and while I know that isn't a substitute for actual research, it usually turns up ''something''. So if there are any naturalists or bird afficionados out there I'd appreciate some information.
thnx. [[User:Jasongetsdown|Jasongetsdown]] 18:37, 5 December 2005 (UTC)
:I'm not sure what bird the person was referring to. They mention the ''loon'', which is ''lan ren'' in Chinese. Then, ''nightingale'' is mentioned, which is ''ye ying'' in Chinese. The first thing that comes to mind is the use of ''xu'' for ''fake''. As such, ''xuguo'' means to make something up and ''xuwei'' means false. But, another use of ''xu'' is to indicate an animal is domesticated. But, it is commonly pronounced ''chu'' when used that way (the proper pronunciation is ''xu'', but because it is often followed by ''sheng'', it becomes hard to say ''xusheng''). Finally, there is a surname Xu. Since the person capitalized Xu every time it was used, perhaps the family Xu has a special bird named after them. All in all, there is no bird named Xu in my dictionary. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 01:00, 6 December 2005 (UTC)
== Why are old things buried? ==
'''What is the mechanism by which all things get buried with time'''? Is it always slowly raining soil out of the sky? it seems that the older a thing is, the deeper it is buried. Why is this so?
Thanks
--[[User:216.130.131.66|216.130.131.66]] 19:34, 5 December 2005 (UTC)Frank Allen
********@******.*** <email addressed removed>
:It is not the case that old things are always buried. Some things are pushed to the surface over time. For example, I live on an old plantation where multiple civil war battles were fought. When I work in the yard, I still find old things being pushed up to the surface after every rain. I'm sure some things are pushed down as well. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 20:36, 5 December 2005 (UTC)
::I don't think Civil War-era artifacts are "old" in the context of the question. But sure, buried things sometimes get unburied. Then they usually don't last very long. I think that's part of the answer to the question: Things get either buried or destroyed, and we don't find the destroyed ones.
::But no, it's not about "soil raining from the sky", mainly. Successive layers of sediment are generally added by water—either at the bottom of a body of water (since perhaps disappeared), or by flooding of rivers in an alluvial plain. Lots of different things can happen after that. With luck, maybe a geologist will come along and explain more specifically. --[[User:Trovatore|Trovatore]] 20:50, 5 December 2005 (UTC)
Gravity tends to push things downward, especially if they are relatively dense and the soil is moist, but more generally things tend to get buried as material accumulates on top of them. Dead leaves, soil that gets moved around, dust. Things tend to be exposed by erosion, but what erodes somewhere has to deposit somewhere else. Plant roots can bury something (imagine a tree growing up on top of an object) or expose them (imagine the tree falling over and the roots tearing the object out of the ground). Then add the magic factor of time... [[User:Guettarda|Guettarda]] 20:50, 5 December 2005 (UTC)
::[[Erosion]] is the mechanism where [[Weathering|broken down]] rock or soil moves around the place. Where I live, the local "hills" are weathering and eroding (ie moving) down towards the city. I guess in a long time the city will get buried. Basically the weathered rock, [[sediment]], can be pushed around by wind or water (if you are under the ocean or a river) and will bury stuff. --[[User:Commander Keane|Commander Keane]] 20:54, 5 December 2005 (UTC)
: "Is it always slowly raining soil out of the sky?" It a way, yes. Plants take carbon dioxide from the atmosphere and use the carbon in it to make their bodies (wood, leaves, etc). When a plant dies it falls to the ground where it rots. The action of the rotting returns quite a lot of that carbon back to the atmosphere (as carbon dioxide again). But some gets buried by more dead plant material ([[leaf litter]] and stuff) before it has had a chance to fully decay. Buried, there's little oxygen; it keeps decaying, but without oxygen the bacteria that decay it can only work very slowly, and they never manage to finish the job. Over the years and centuries new plants grow and die and partially decay, and each summer adds another thin layer of material, piling up on what's underneath. So eventually things that once were on the surface are covered by metres of material. [[Peat]] is formed this way, and is often many meters thick. A similar process happens in the sea, with little plants and animals that live in the [[photic zone]] (near the surface, where there's lots of light) dying on the surface; their little bodies rain down on the sea floor (that's [[marine snow]]) and it piles up, year after year. Sometimes this piles up for tens of millions of years, and eventually becomes [[chalk]]. -- [[User:Finlay McWalter|Finlay McWalter]] | [[User talk:Finlay McWalter|Talk]]
::Darn it, this guy got to it first. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 22:28, 5 December 2005 (UTC)
::Which still leaves the question where the material comes from (the net result). I suppose part of it is the trees with deep roots that 'suck up' material from the ground and then dying, falling and depositing it on the ground (as Finlay pointed out), effectively turning the ground upside down. By the way, I believe Darwin investigated this too (measuring accumulation in his back yard), but I don't remember what he found. I vaguely remember it was something to do with snails. [[User:DirkvdM|DirkvdM]] 12:40, 6 December 2005 (UTC)
== Areola changing size monthly? ==
Do the [[areola]], [[lip]]s, etc. change sizes periodically according to the [[menstrual cycle]]?
:Interesting question. Though the article only mentions the breasts, I suspect [[premenstrual water retention]] affects other body parts as well. —[[User:Keenan Pepper|Keenan Pepper]] 17:26, 6 December 2005 (UTC)
== Why Doesnt Oil and Water Mix? ==
Im Just wondering, why doesnt water and oil mix?
Thanks, Dave
[[Water (molecule)|Water]] is a [[polar molecule]] - [[oil]] is not. Because this difference of this difference in the types of [[chemical bond|chemical charge]], it is hard to form the weak bonds which allows anything to mix with another object (ie. form a [[solution]]) - without settling. -- [[User:Natalinasmpf|Natalinasmpf]] 21:53, 5 December 2005 (UTC)
:A little-known aspect of this is that the attraction between an oil molecule and a water molecule is actually stronger than the attraction between two oil molecules. The reason they don't mix is because the attraction between two water molecules is much stronger than either of those (because of [[hydrogen bond]]s). It's like the water molecules form a clique and although the oil molecules want to join, they can't because the water molecules don't think they're cool enough. (Silly little metaphor, but it helps. =P) ——[[User:Keenan Pepper|Keenan Pepper]] 22:06, 5 December 2005 (UTC)
Interestingly, it's been found that when all dissolved air is removed from both liquids, they do mix. As far as I know there's no explanation for this yet. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 22:30, 5 December 2005 (UTC)
:: Maybe because removing the gases affects pressure, and would affect the [[self-ionization of water]], or something. Do hydronium and hydroxide ions play a part in the solution formation? I would imagine. Of course this is only a wild guess. -- [[User:Natalinasmpf|Natalinasmpf]] 22:46, 5 December 2005 (UTC)
:Do you have a reference for this? —[[User:Keenan Pepper|Keenan Pepper]] 23:59, 5 December 2005 (UTC)
::Sadly I can't remember where I saw it. Maybe in Science News somewhere, but I can't remember the date, nor can I remember my pass to the site. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 01:04, 6 December 2005 (UTC)
:::The mixing should not be any surprise...in an oil and water mixture, there is always a slight amount of one substance dissolved in another - it just might not be an appreciable amount. --[[User:HappyCamper|HappyCamper]] 01:18, 6 December 2005 (UTC)
::::It was complete, like salt and water.
=December 6=
== Petroleum jelly ==
Why isn't petroleum jelly harmful for human use?
:Everything is harmful to humans in excess. You can overdose on water and oxygen. Petroleum jelly has a long history of providing health benefits. It has also been consumed in small quantities by some who believe it is good for the digestive system. If taken in excess, it is harmful. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 00:32, 6 December 2005 (UTC)
:It doesn't react with most organic substances, and doesn't contain many aromatics. [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 15:46, 6 December 2005 (UTC)
== Starch and sugar ==
Why might a plant storage organ (such as a fruit or tuber) contain both starch ''and'' sugar? Thanks. --[[User:69.165.33.225|69.165.33.225]] 01:33, 6 December 2005 (UTC)
*Starch is a form of sugar, see [[Polysaccharide]] --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 01:35, 6 December 2005 (UTC)
Do they seem mutually exclusive to you? Sorry not sure what you are getting at. [[User:Alteripse|alteripse]] 01:36, 6 December 2005 (UTC)
*Are you asking why it might contain polysaccharides and monosaccharides? If so, then here is my answer. Sugars are usually stored as polysaccharides (why that is, I'm not ''exactly'' sure); glycogen is the main storage form in animals, and cellulose is for plants. To be used for an energy source the polysaccharide has to be broken down into a monosaccharide (usually glucose). So when a cellulose molecule in a plant is broken down, you could have both polysaccharides and monosaccharides at the same time.[[User:Dimblethum|Dimblethum]] 05:02, 6 December 2005 (UTC)
**Cellulose is different from starch in that it uses beta bonding. Starch molecules are used because they are more stable, I think. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 05:50, 6 December 2005 (UTC)
*** That's only half the reason. The other reason is that glucose is quite small, so it can be easily lost by the plant to the environment, along with your oxygen and carbon dioxide. -- [[User:Natalinasmpf|Natalinasmpf]] 22:07, 6 December 2005 (UTC)
==AOL installation dies on me==
:What's up with these errors?? I have no idea why i'M getting them, AOL has always installed just fine in the past (''AOL spyware not withstanding''), and now everytime I start the process I get these..
:[[Image:aolBAD.jpg|thumb|this]] & [[Image:aolBADw.jpg|thumb|followed by this one, then a crash]]
:As an alternative, would anyone know where I can find a '''much''' older aol installation? online? something like '''AOL 5.0''' or '''6.0''', so I don't have to put up with all the addweary goodness that is '''9.0b-SE'''--[[User:Aolanonawanabe|Aolanonawanabe]] 23:49, 29 November 2005 (UTC)
*bump* I forgot to mention I'm in a hurry--[[User:Aolanonawanabe|Aolanonawanabe]] 00:18, 30 November 2005 (UTC)
::Well, I can't help with the error message, but there appears to be an AOL 5.0 version for download at [http://www.oldversion.com/program.php?n=aol this site]. I've never used it before, but it looks to be fairly legitimate. --[[User:ParkerHiggins|ParkerHiggins]] 01:06, 30 November 2005 (UTC)
::*I don't suppose you'd know off the top of your head, if AOL 5.0 had support for cable/DSL?--[[User:Aolanonawanabe|Aolanonawanabe]] 01:20, 30 November 2005 (UTC)
:::Well, a quick google determined that "AOL 5.0 has resident broadband support capability" (from [http://www.fool.com/community/pod/1999/pd991101.htm this site] with the annoying pop-up). I think that means you're a go, but I can't be sure. You can check on the article, if you're in doubt. --[[User:ParkerHiggins|ParkerHiggins]] 01:27, 30 November 2005 (UTC)
::::Installation worked, this time crashed '''after''' installation finished [[Image:thisclose.jpg|thumb|''so close'']], thanx anyway though--[[User:Aolanonawanabe|Aolanonawanabe]] 02:11, 30 November 2005 (UTC)
:::::Might I ask why AOL? --[[user:frenchman113|frenchman113]]
::::::Their bizaire fu#$%ed up proxy system does make for a nice bit of privacy/anonymity, even if it is just a side effect--[[User:Aolanonawanabe|Aolanonawanabe]] 01:55, 6 December 2005 (UTC)
===Why, I say, why?===
*It still doesn't finish the installation, and at this point I'm more curious why, than anything else--[[User:Aolanonawanabe|Aolanonawanabe]] 01:55, 6 December 2005 (UTC)
:*Windows is a very broken thing hobbled by having to be backward compatible and a certain amount of poor design and failure to iron bugs out, so I'm surprised you would even ask why. On top of that, various installs and uninstalls of other software could easily leave your system in a broken state, that could interfere with the current install. The only solution to some windows failures is a clean install, but people will tell you that can be very risky as the distributor that installed in the first place had worked out all the driver issues etc, and probably had an image they ghosted onto the drive. You don't have that, so the reinstall could be risky. That said, I've used the OS reinstall disks that come with dells several times and they general work pretty well. So I'd say backup backup, get all your application install cd's and have a clean go at it. - [[User:Taxman|Taxman]] <sup><small>[[User talk:Taxman|Talk]]</small></sup> 13:59, 6 December 2005 (UTC)
== Medical/psych question ==
Hey, this probably isn't the right place to ask this, but I have a question re mental health,fulfillment, and psychiatric meds.
I've got a great psychiatrist. He brought me back from a really bad place. I'm taking four different meds every day to keep things in the old brain operating normally, and as long as I do so I am able to deal with my feelings that life is utterly meaningless and lagerly devoid of pleasure and happiness.
That's what the meds are supposed to do - allow me to handle my feelings. Here's the thing - I'd like to enjoy life and be happy sometimes, not just not be overcome. I'm currently in therapy, and practicing cognitive behavior therapy. It is interesting but not efective in making me happy.
Is there any medicine that makes you happy? I have a _large_ family to support, and would rather not just exist as the food, shelter, and cash producing machine. I'd really like it if I could enjoy life as well.
What did your psychiatrist say when you asked him that same good question? [[User:Alteripse|alteripse]] 02:52, 6 December 2005 (UTC)
I wouldn't say there was. Besides, medicines that make you "feel" happy IMO would be kind of an empty, meaningless happiness....I am reminded of the "happiness" induced in Huxley's "Brave New World". Medication to relieve depression is one thing, but to seek happiness I would indulge in [[philosophy]], [[metaphysics]] and [[Nicomachean Ethics]], not medication. -- [[User:Natalinasmpf|Natalinasmpf]] 04:51, 6 December 2005 (UTC)
:I think there's a middle ground in there. I agree with Natalinasmpf that there are no psychiatric medications that ''make'' you happy, nor would you likely want them if there were. At the same time, many people, myself included, have better experiences with meds than something that merely allows you to function while still having depressive feelings. It's a fine line to draw, I know, but my experience is that the medicine didn't ''make'' me happy, it ''allowed me to be'' happy. On medication, I wasn't some unnaturally cheery person who was always happy regardless of the circumstances; but I was happy some of the time, more or less when you would expect a normal person to be, whereas when I had been depressed and not on any medication, I was constantly sad, even when I had no reason to be. If that's something you want to explore with your psychiatrist, talk to him/her about either increasing your dosage or switching medications. The danger is that the reaction to psychiatric medications varies greatly from person to person--what works wonders for one person is completely ineffective for another, and vice versa--and the only way of knowing what works best for you is experimentation. So if you do try switching medications, the danger is that you may give up even the functionality you've achieved so far. Whether that's a risk you're willing to take is between you and your psychiatrist. [[User:12.223.56.106|12.223.56.106]] 09:26, 6 December 2005 (UTC)
*Taking medication that makes you feel happy is just kidding yourself. Perhaps if the therapy works your psych will decide to lower the dosage somewhat. Still, the best way to feel happy is to do stuff you like to do with friends and family. - [[User:MacGyverMagic|Mgm]]|[[User talk:MacGyverMagic|<sup>(talk)</sup>]] 11:20, 6 December 2005 (UTC)
== Prolog ==
Is it possible to implement an equality check for "arrays" in Prolog? I am running into a problem where my particular version of Prolog is comparing memory addresses instead of the actual array contents in the recursive check. Any tips? --[[User:HappyCamper|HappyCamper]] 03:11, 6 December 2005 (UTC)
:If you're using "A == B" (A identical to B) you might try "A ?= B" (A unifiable to B). If you're actually using lists, and they're fully instantiated (no uninstantiated elements), "A ?= B" should tell you whether the lists contain the same elements (recursively, all the way down to atoms) in a single expression. -- [[user:Rick Block|Rick Block]] <small>([[user talk:Rick Block|talk]])</small> 03:24, 6 December 2005 (UTC)
::Hmm...let me try that. I'm using SWI prolog if that makes a difference... --[[User:HappyCamper|HappyCamper]] 03:27, 6 December 2005 (UTC)
== Active polymer material which acts as an antiback agent in textile washing industry ==
== Will pressure different inside and outside a building? ==
Will the air pressure different inside and outside a building?For a building near the sea,will the air pressure different too?
:For the most part, no, there will be no difference. Buildings are not airtight, and even if they were, the pressure would rapidly equalize as soon as anyone opened a door. One exception to the general rule would be inflatable domed sports stadiums, such as the [[RCA Dome]], where a roof of flexible fabric is held up by air pressuree. In these, the pressure is retained while people enter and exit via revolving doors. There are also conventional doors which can be used as emergency exits, but the pressure difference does create a stiff breeze if these are opened. [[User:Chuck Carroll|Chuck]] 09:09, 6 December 2005 (UTC)
::Skyscrapers also seem to have a stiff breeze when doors are open; perhaps they have trouble equalizing pressure because the ''external'' pressure is different between the top and bottom? -- [[User:SCZenz|SCZenz]] 09:15, 6 December 2005 (UTC)
:::It shouldn't be because of the pressure difference between top and bottom, either externally or internally. The difference in pressure due to altitude is an effect of gravity, and it would have the same effect both inside and outside the building. (That is, the external pressure at the top of the building will be less than the external pressure at the bottom, but at the same time the internal pressure at the top will be less than the internal pressure at the bottom.) I'm just guessing here, but I suspect that skyscrapers, while not perfectly airtight, have few enough spaces for gas to escape that it is possible for a pressure differential to build up, just as a result of ventilation, possibly with effects due to heating or cooling the air inside the building too. Note that skyscrapers also generally don't have windows that can be opened, limiting the ways in which the external and internal pressures can equalize. [[User:Chuck Carroll|Chuck]] 09:32, 6 December 2005 (UTC)
:*One would think the answer is yes, in certian situations, this is after all the cause of most tornado damage--[[User:Aolanonawanabe|Aolanonawanabe]] 11:42, 6 December 2005 (UTC)
::No, tornado damage is caused by the wind. It was at one time thought that when a tornado was approaching, one should open a window to "equalize the pressure," it's now known that this is unneccessary, and in fact it is strongly recommended that one ''not'' open a window. See [http://www.spc.noaa.gov/faq/tornado/#Safety here] and [http://www.avma.org/disaster/responseguide/E_tornadoes.pdf here] for examples. [[User:Chuck Carroll|Chuck]] 13:46, 6 December 2005 (UTC)
::*All that says is that openning a window is pointless and would just scatter broken glass anywhere, it doesn't say anything about there '''not''' being a preasure difference, not to mention wind '''is''' a preasure difference--[[User:Aolanonawanabe|Aolanonawanabe]] 15:43, 6 December 2005 (UTC)
:Air flow, such as wind, causes pressure to drop (this principle is also used in wings). So if a wind starts blowing, there will be a difference in air pressure, causing air to flow out at a rate dependent on the size (and ___location?) of apertures. And when, after satbilising, the wind (suddenly) drops, there will again be a pressure difference. About the ___location of the apertures. Suppose they are all at the windward side. Then I suppose air will get blown in, causing air pressure inside to actually increase despite the decreased outside pressure. [[User:DirkvdM|DirkvdM]] 14:25, 6 December 2005 (UTC)
::That is very correct. A house cannot adjust pressure immediately. Wind also creates lift on the roof. Combined, many roofs give way and blow down the road. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 16:57, 6 December 2005 (UTC)
:::If your building is large enough then you may notice a Helmholtz Resonator. If this is the case then pressure in the building will periodically move up and down. For the Helmholtz Resonation to work, you need a dominant opening (ie a big door) and for the rest of the building to be virtually sealed (note: a shopping centre provides perfect conditions). When wind hits the opening it goes into into the building and sqeezes/compressses the air inside - increasing the pressure. The air then expands back, and the pressure drops. The process repeats itself.
::: Helmholtz resonation occurred at a local shopping centre. When it was raining it was noticed that the rain was getting "sucked" about 10 metres into the building - and stores were getting soaked. In the neighbouring post office the rain was only getting sucked in a couple of meters - the large, sealed nature of the shopping centre was allowing resonation which periodically sucked in air (and rain), and peridocially forced out air (but not the rain, which was saturating the store displays). The solution was to reduce the size of the dominant opening, with a glass wall replacing to old big door, and a side door installed. This is illustrated below, not to scale.
_______________
| |
| |
| |
| |
| |
|____ ___|
<small>new door =></small> /_______|
:::--[[User:Commander Keane|Commander Keane]] 21:52, 6 December 2005 (UTC)
== Kerosene and burning it. ==
I have searched everywhere but was not able to find the answer I was looking for.
If I pour kerosene (ordinary kerosene) into a cup (a standard cup in which you drink tea) and then bring a lighted matchstick over it, will it burn? I am sure it will not, but my friends at work say it will and have bet me one cup of tea. I also remember doing this exact thing when I was a young kid and it did not.
:Various web pages, such as [http://www.chemistry.ohio-state.edu/ehs/handbook/flammabl/oshafire.htm this one], give the [[flash point]] of kerosene as 110° Fahrenheit (which is 43° Celsius) or somewhat higher. In order to start it burning you would have to warm some of the kerosene to at least that temperature. A match held very close to the liquid might very well do it: after all, people light kerosene lamps easily enough. But a match held "over" the cup at a short distance might not (even though a more dangerous fuel like gasoline would ignite). I would not want to speculate as to how close you bring it in safety. Indeed, I'd say "don't try this at home, kids." --Anonymous, oh my look at the time, 10:10 UTC, December 6, 2005
::I think the vapour pressure of kerosene at room temperature in low enough that it is actually pretty hard to light. I have seen someone demonstrate this by dropping a lit match into a container of kero. The match went out. Kero lamps use presure or wicks to help vaporise the kerosene before burning it. --[[User:Martyman|Martyman]]-<small>[[User_Talk:Martyman|(talk)]]</small> 11:03, 6 December 2005 (UTC)
:::Keep in mind that the liquid does not burn. The vapor/fumes/gasses burn. In a lanp, you light the wick, which heats the kerosene that has crept up the wick. At first, you are burning cotton (or something similar). As the heat builds up, you begin burning fuel instead. On a similar topic, I did an experiment with lighting a milk carton full of gas and one with just a little gas in the bottom. The full one caught on fire and made a mess. The empty one exploded and left a hole in the ground. Once again, the reason was that the fumes burn - not the liquid. So, going back to the original question, holding a match over the liquid to try and get it to start evaporating should get a flame started, assuming the match doesn't burn your fingers first. --[[User:Kainaw|Kainaw]] <small><sup>[[User_talk:Kainaw|(talk)]]</sup></small> 16:52, 6 December 2005 (UTC)
== "How can i make women attracted to me"? ==
:If you want the slimy method of doing so, do a Google search for "seduction" and there's all manner of people who are prepared to sell you all sorts of grooming, conversational, and body-language tricks that are supposed to help seduce women. The proprietors swear by them; independent endorsements are a little harder to find. If you want a little chemical help of the legal and ethical kind, there are other people who sell pheromones which are supposed to mimic the natural pheromones that women find attractive. You mileage may vary. Personally, I very much doubt there's any magic short cuts; dress sharp, be nice, be confident, and search for women who are interested in the same thing as you (be that a one night stand or a longer-term relationship). --[[User:Robert Merkel|Robert Merkel]] 10:56, 6 December 2005 (UTC)
Pretty much the biggest attractors (varying in importance for a given woman) are a great personality, confidence, money, looks, and talent. If you have at least one of the five and are persistent enough, at least some women will be attracted to you. Playing the numbers game works pretty well to, partly becaue it takes confidence. Ask 20 women out and have something interesting to say and you'll probably be successful with a lot more than one. You can of course work to improve on as many of the above five as possible, but confidence alone does work. - [[User:Taxman|Taxman]] <sup><small>[[User talk:Taxman|Talk]]</small></sup> 13:37, 6 December 2005 (UTC)
:great summary :) "confidence alone does work" is only too true, sadly leading to the spawning of legions of male jerks. So if the question is intended to read "any woman" rather than "a particular woman", your best bet is to become a megalomanic jerk. [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''ᛏ''')]]</small> 13:43, 6 December 2005 (UTC)
::Thanks :) The problem is compounded by the wierd fact that a large number of women are attracted to "bad" guys and some even to guys that treat them like crap. Of course nice guys that figure out a bit of the game are much more likely to end up in a fulfilling relationship, and the jerks get their due in the end. Good stuff below too. - [[User:Taxman|Taxman]] <sup><small>[[User talk:Taxman|Talk]]</small></sup> 22:35, 6 December 2005 (UTC)
(assuming you're a guy) I once did a little unofficial field (street) study of what type of men walk around with pretty women and I found that they could be roughly classified as either 'bikers' or 'yuppies' (this was in the early 1990's). So my conclusion was that (pretty) women are attracted to men with power, be it physical (old style power) or financial (new style power). In an evolutionary sense this makes sense because the offspring needs to be protected. That creating offspring is nowadays hardly a reason to start a relationship is irrelevant. It's the environment we evolved in that determines our sexdrives (which 'love' and such basically come down to - excuse me for being so down to Earth). Of course this is related to the confidence thing; you can also fake it. And the 'dressing sharp' fits in with the yuppie type (for the biker type 'sharp' is not quite the word). Finding a woman who is interested in the same things as you sounds logical, but I have my doubts. Studies have shown that people can 'sniff out' those with a different DNA-makeup, to whom they are more attracted. This also makes sense evolutionarily. If same-type people were mutually attracted that would be sort of inbreeding. I mean the 'sniffing out' quite literally - smell seems to be an indicator for this. So if you want this to work, you shouldn't really wash too often and certainly not use soap. So why don't I have a woman then? :) [[User:DirkvdM|DirkvdM]] 14:47, 6 December 2005 (UTC)
:Alternative answer: You probably can't make women attracted to you.
:This is not the answer you want to hear, but I'm of the "Tough Love" school of anonymous advice giving. If I told you to "be yourself" and "have self-confidence" you would probably just groan. God knows I heard enough of that as a horny youth, and despite it being true, it still didn't help me worth a damn. You want an instruction list, you want something to do, and you want to feel that it will work. That I'm prepared to offer you. You also probably want something cheap, simple and guaranteed effective; and that is exactly what you will not get from me or anyone else. Anybody selling you a guaranteed effective way to get women is selling you [[snake oil]]. Harsh.
:I am assuming the question is being asked from a heterosexual perspective - if it is not then I can't tell you much of use as I'm afraid I am congenitally ill-equipped for lesbianism.
:Now, here's the harsh truth: You can't make women attracted to you. You think that many women can make you be attracted to them, but they can't really. Sexual arousal is something that happens in your brain. It's something you do to yourself, not something they do to you. Men and women alike usually think that men have a button that you can just push that makes them horny while women don't have one, but this is nonsense. I know I sound like that cliché ''"the most important sexual organ is your brain"'' stuff, except that it's not a cliché. It is true for very sound, straightforward physiological reasons that ought to be a part of basic sex-ed but somehow aren't.
:But that's not what you mean. What you mean is that you see an attractive woman, and you feel aroused. It doesn't matter if she's trying to be sexy - if you have any awareness of what she is trying to do at all - or whether she has the slightest interest in you. You are just turned on and you don't care about neuro-physiological modelling. What you want to know is how you can make her feel the same way as you do just by coming in contact with you.
:Next harsh truth: Unless you have the body of a professional underwear model, a successful career as an actor in romantic comedies, more money than you can hope to spend, or your name appears towards the top of [[Line of succession to the British Throne|this list]], you probably can't make them feel as helplessly attracted to you as you feel towards them. The reasons for this rather troubling but entrenched bit of gender inequality are complicated, controversial, and in my opinion primarily sociological. (Although the popular media has been covering a lot of evolutionary and biochemically-driven thinking on this subject in the last 20-odd years which I must confess to finding almost complete bunk.) However, regardless of its cause you can't do a damn thing about the ugly fact that you are hot for lots of women who have no idea you exist, so there is precious little point in dwelling on it.
:But, even if you can't ''make'' women interested in you, there are a number of things you can do that improve the likelihood that they will ''become'' attracted to you without you having to ''make'' them do anything. Women, you see, are ''sometimes'' interested in men without men actually having to do anything in particular. It's a novel concept to a lot of men - I know, it took me a while to cope with - but heterosexual women sometimes feel about men much the way men feel about them. Actually, they do fairly regularly. Not with quite the panicked obsession that men feel towards them, but western society rewards female sexuality differently than male sexuality so that is to be expected. Otherwise, they are, in fact, a lot like men in terms of sexual responses. It's a strange sort of symmetry, but it's kind of neat that it works out that way.
:The things you can do to make women more likely to actually ''want'' to be interested in you are, in my experience and roughly in order of importance, as follows:
:#Try not to smell bad.
:#Shave your nose hair.
:#Maintain fresh breath at all times.
:#Lose weight and try to stay in shape.
:#Listen carefully when they talk or at least have the courtesy to pretend.
:#Dress well.
:#Get a decent haircut.
:#Have good posture.
:Why these simple, straightforward, uncomplicated facts are not introduced to young people at an appropriate age through the public school system is beyond me. It is as if the entire function of sex education is to ''prevent'' people from having healthy, happy, reasonably fulfilling and self-esteem reinforcing sex lives. Certainly making a point of this type of thinking earlier in life would save young men enormous amounts of pain, embarrassment and depression.
:Alas, some of these things are not easily changed from one day to the next. Breath mints are cheap, and do try to floss. Use deodorant. Expect to pay at least €20 for a haircut - and not at that discount place by [[Walmart]]. A nose hair trimmer will set you back circa €10. Staying in shape if you are under 25 and metabolically normal will likely require a commitment of at least 5 hours a week and more if you are older, and may take months to have sufficient effect. Exercise will, however, probably help with your posture too.
:An adequate wardrobe requires the advice of a friend or two and probably several hundred bucks. I'd try to get one before they raise tariffs on Chinese textiles again. My advice is to cultivate a small circle of women in whom you are not sexually interested and to whom you are not closely related - e.g., not your mother - and get them to help you pick some clothes and a decent cologne. This is - ''and you should be taking notes now!'' - exactly how women go about learning to make themselves attractive to men. They have friends - older or more experienced female friends - who help them shop for clothes, perfume, grooming materials, haircare products and who go with them to stylists and help them to pick out a 'do. Indeed, many women - quite possibly a large majority - seem to actually enjoy this sort of thing. I can only presume men do not take advantage of this resource because they are unaware of it or because they foolishly think they will get better advice from other men.
:As for the ''paying attention'' part, it is a bit of a trick, especially when it's all you can do to keep from staring at her breasts. The best way to go about it that I've found is to have the sense to look sheepish and like you are trying to hide it when you are caught checking out her breasts and/or butt. That way, women can feel that you find them attractive without feeling that you are creepy, and it helps to manage many of those moments when organs other than your brain have immediate motor control.
:Actually showing interest is not so easy and takes some practice. But, start with remembering that no matter that your interest in them may be limited, their interest in themselves is as considerable as ''your'' interest in ''yourself''. Women are a lot like men, just with breasts and without penises and usually with better hair. Except that they can't easily pee while standing up, they relate to the world in very similar ways to men. Try to relate to women the way you might relate to men who have something you want and that they might give to you if you cultivate them carefully - like potential employers or teachers or other men that you treat with some consideration - and you will stand an okay chance with women.
:--[[User:Diderot|Diderot]] 17:43, 6 December 2005 (UTC)
::Wow, could you maybe trim that down somewhat and write it up at [[Sexual attraction#Factors determining sexual attraction to human males]]? I'd hate to have all this detailed information go to waste in the reference desk archive. Heck, we could even start a wikibook on how to attract women... Oh wow, there already is one. I should have figured... =P —[[User:Keenan Pepper|Keenan Pepper]] 17:59, 6 December 2005 (UTC)
::::Well, if it's on this page it's all GFDL, so go for it. Actually, I've been wondering if I can find a gig as an advice columnist somewhere, seeing as how I'm ''between engagements'' at the moment. --[[User:Diderot|Diderot]] 18:35, 6 December 2005 (UTC)
:::My turn! Instead of grooming tips, which actually are good ideas all around, because stinky overweight people do not usually get offered good jobs. I am an engineer, so I am disqualified from giving grooming tips. If you want a shallow relationship I can't help you. Find someone like you. You would be surprised. There is some girl out there who is looking for a guy with your interests. By this I mean, there are few girls out there looking for a guy to hump her leg, find a girl who likes the things you like. If you are not meeting people, then go out and meet people by being active in the things you like to do. I like gaming, and I go to gaming conventions, but if I want to be social, I may go to book oriented activities, these are related to the things we do in gaming, but are bound to be more social than gaming with six people and a DM.
:::So meet women, lots of women. Making friends with no dating interest should be the first goal. Even if you meet a lot of other guys, thats OK. They may know girls that have your same interests. If you go to bars, you will meet people who like that. If you go to churches you meet church people. The moral there is the same. You will meet a lot of girls who you have no interest in or have no interest in you. I estimate the odds are a million to one. There are a million girls who do not want to date you, and one who does. Start working your way through the million. If you lock yourself in a closet, your chances are poor.
:::One other thing, if she isn't interested move on. Don't fixate. A girl will want to be with you as much as you want to be with her, if it is right. Don't chase a woman based on looks. All women eventually get older, and will looks more like grandma, and so will you (well like grandpa). If you are lucky enough to date [[Sophia Loren]] or [[Raquel Welch]] who age better than most then good. A good woman who likes you will look better than they do anyway. [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 18:02, 6 December 2005 (UTC)
::As a woman, I must say: nose hair? I don't know that I've ever noticed a guy's nose hair... then again, maybe it's because they've trimmed it. :-) [[User:Mindspillage|Mindspillage]] [[User talk:Mindspillage|(spill yours?)]] 23:02, 6 December 2005 (UTC)
:::I might ask if your background includes any significant number of men of Central and Eastern European ancestry? I assure you, there are communities where even the ''women'' need to trim their nose hair. Alas, I am from such a community and that particular lesson was a hard won one. --[[User:Diderot|Diderot]] 23:16, 6 December 2005 (UTC)
*Those of us with large hands, but no other attractive characteristics, know that you can start a girl's attraction to you simply by putting your hands on her shoulders and moving her someplace, gently. (It normally helps if there's a logical reason to be doing this.) For me, getting them ''attracted'' is the easy part; doing and saying the right things to actually satisfy hormonal instinct is the hard part, and I suck at it, a lot. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 03:16, 7 December 2005 (UTC)
== smallest vertebrate of the world ==
The [[shrew]] article notes that the [[Pygmy White-toothed Shrew]] is the smallest living ''mammal''. It weighs 2 grams. I would assume the smallest ''vertebrate'' would be some kind of tiny fish. [[User:Jasongetsdown|Jasongetsdown]] 17:25, 6 December 2005 (UTC)
:Could it be [[Schindleria brevipinguis]], the stout infantfish? —[[User:Keenan Pepper|Keenan Pepper]] 17:33, 6 December 2005 (UTC)
== Face recognition ==
How far away are we from the face recognition technology of "The Island"? --[[User:Phil 1970|Phil 1970]] 17:36, 6 December 2005 (UTC)
:I would say we are still very far. [[Computer vision]] is widely regarded as an [[AI-complete]] problem, and right now I doubt there's a program that can even reliably tell if a face is frowning or smiling (anyone want to contradict that?), much less tell whether two images are of the same person. —[[User:Keenan Pepper|Keenan Pepper]] 17:47, 6 December 2005 (UTC)
::I think face recognition was implemented commercially at many major american events after September 11. I believe the first case I can think of was at the superbowl. I seem to recall there is a proposal to implement it as part of the London Tube security upgrades. See: [[Facial recognition system]]. Of course the reliabilty of these systems is questionable. --[[User:Martyman|Martyman]]-<small>[[User_Talk:Martyman|(talk)]]</small> 21:11, 6 December 2005 (UTC)
:::Face recognition is a lot better than you'd think. Now the [[cloning]] technologies in The Island? Bullshit. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 00:46, 7 December 2005 (UTC)
==Microsoft word==
I do not have Mkicrosoft word on my computer and I wish to have it as what I currently have isn't getting me anywhere. Does anyone know any sites that you can download Microsoft Word, not some update, on to their computer. I really need it. Thanks!--[[User:XenoNeon|XenoNeon]] 17:59, 6 December 2005 (UTC)
:It's proprietary software that costs money. You have to go to the store and buy it in a box, or get it illegally from a pirate. —[[User:Keenan Pepper|Keenan Pepper]] 18:01, 6 December 2005 (UTC)
:Silly me, I forgot to suggest [[OpenOffice.org]] or [[AbiWord]] instead. =P —[[User:Keenan Pepper|Keenan Pepper]] 18:02, 6 December 2005 (UTC)
Thank you very much. You're a lifesaver! You deserve a reward. Honestly!--[[User:XenoNeon|XenoNeon]] 18:37, 6 December 2005 (UTC)
:Hm, I use OpenOffice; didn't know about AbiWord. Anyone care to compare the two? Does AW have sufficient advantages over OO to make it worth my time to download it, set it up and try it out? --[[User:Trovatore|Trovatore]] 19:33, 6 December 2005 (UTC)
::Abiword is merely a word processor - OpenOffice.org also contains functions for spreadsheets (like [[Excel]]), presentations (like [[PowerPoint]]), databases (like [[Access]]), among others. What will work for you depends on what you want - sometimes the [[multi-tool]] is ideal, sometimes you want something specialized. Just download and try it to check if it suits you - it won't cost you very much unless you're on dialup or pay per megabyte downloaded. [[User:TERdON|TERdON]] 20:41, 6 December 2005 (UTC)
:I use OpenOffice 2.0 as well. Love it. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 03:10, 7 December 2005 (UTC)
There's also a free Microsoft Word Viewer available for download from Microsoft.[http://www.microsoft.com/office/000/viewers.asp] It won't let you edit documents, but it's a convenient little tool for reading them. —[[User:Ilmari Karonen|Ilmari Karonen]] <small>([[User talk:Ilmari Karonen|talk]])</small> 23:32, 6 December 2005 (UTC)
== How does Arm and Hammer Washing Soda Dissolve an Olive Oil Stain (Just it and Hot Water) ==
Dear Happy Camper,
I wasn't sure how to answer your response to my December 1, 2005 , 1.15 question, so I edited it there and wrote this as a "new" question to a question. If wrong, I am sorry since I am new to this.
The laundry detergent used was good old fashioned Arm and Hammer Washing Soda.
A 1/2 tablespoon was put in 16 ounces of hot water with no other detergent (water is "soft") to remove an olive oil stain from cotton. A half an hour later, Voila,! No stain. How did it dissolve the stain.
Thanks for your help and any others.
--Just Wondering
Look at [[emulsify]] and [[detergent]]. A base, that is a high pH chemical, can cause oils to dissolve in water. [[User:Dominick|Dominick]] [[User_talk:dominick|<sup>(TALK)</sup>]] 19:28, 6 December 2005 (UTC)
== Regarding nuclear decay: ==
In types of decay which emit neutrinos or antineutrinos (beta decay, I believe), where's the neutrino come from, and why does it get emitted?
Also, with types which involve a neutron becoming a proton (such as in beta decay) or vice versa, what causes the change?
I never was able to get an answer to these in any of my science classes.
--[[User:Mr. Fluffles|Mr. Fluffles]] 20:24, 6 December 2005 (UTC)
:One reason, I believe, is that it's necessary for [[spin (physics)|spin]] to be conserved. The [[neutron]], [[proton]], and [[electron]] each have spin 1/2, meaning their spin in a given direction can have a value of +1/2 or -1/2. If you only had n -> p<sup>+</sup> + e<sup>-</sup>, you wouldn't be able to conserve spin; the left half of the equation would have a spin of either +1/2 or -1/2, while the right half would have a total spin of 1, 0, or -1. [[Photon]]s have spin 1, so throwing one of those in wouldn't help. The electron antineutrino produced in the decay of a [[free neutron]] also has spin 1/2, so once that's added to the equation, spin can be conserved.
:As for the question of why a free neutron decays, I'd say that [http://particleadventure.org/particleadventure/frameless/quantum.html If it can happen, it will.] The neutron is more massive than the proton, electron, and antineutrino combined, so it gives off the excess mass as energy--in the form of a photon--when it decays. For contrast, compare the [http://hyperphysics.phy-astr.gsu.edu/hbase/particles/deuteron.html#c1 deuteron], an atomic nucleus consisting of one proton and one neutron. Because of the binding energy between the two, the deuteron has less mass than its possible decay products of two protons, an electron, and an antineutrino, so the deuteron doesn't break up unless you throw some energy at it. [[User:Chuck Carroll|Chuck]] 22:29, 6 December 2005 (UTC)
::Thanks. --[[User:Mr. Fluffles|Mr. Fluffles]] 01:23, 7 December 2005 (UTC)
:::Also, [[lepton number]] must be conserved. In β decay, you start with a neutron: there are no leptons, so the lepton number is zero. Afterwards, you end up with a proton (lepton number zero), electron (lepton number 1), and an electron antineutrino (lepton number -1); this adds to zero. The antineutrino also carries away some of the momentum and energy of the reaction; the masses and momenta of the products are insufficient to account for the mass and momentum of the reactant neutron. [[Free neutron]]s are inherently unstable and will undergo decay by this process. The "converse" reaction, a proton being converted into a neutron with emission of a [[positron]] and an electron neutrino, is much more difficult; since the neutron has more mass than the proton, energy must be supplied to drive this reaction. A variant of this reaction occurs in the [[proton-proton chain reaction]], one of the fundamental nuclear processes of our sun. According to that article, a proton waits an average of one billion years before being converted into a neutron (and combining with another proton to form a [[deuteron]]. Hope this helps (and hope I'm on the right track)! — [[User:Knowledge Seeker|Knowledge Seeker]] [[User talk:Knowledge Seeker|দ]] 05:01, 7 December 2005 (UTC)
==Is there any ''other'' software like AOL?==
That would allow for similarly anonymous shifts from server to server? Or is AOL a uniquely f#$%^&d up entity?--[[User:Aolanonawanabe|Aolanonawanabe]] 21:28, 6 December 2005 (UTC)
Hey, this is Wikipedia. There's no need for censorship here. :p But of course, moderation of language is good. -- [[User:Natalinasmpf|Natalinasmpf]] 22:01, 6 December 2005 (UTC)
*To be perfectly honest, I was actually going for the humor angle there--[[User:Aolanonawanabe|Aolanonawanabe]] 22:02, 6 December 2005 (UTC)
: If you want real anonymity, use [[Tor (anonymity network)]]. AOL's shifting doesn't really give you much anonymity - we see the same AOL IP address vandalise the same article for days sometimes (I guess others share that address too, and the vandal sometimes gets other addresses too, but by no means is it a "new IP guaranteed for each transation". -- [[User:Finlay McWalter|Finlay McWalter]] | [[User talk:Finlay McWalter|Talk]] 01:36, 7 December 2005 (UTC)
::Noting, of course, that Wikipedia blocks editing from the Tor proxies precisely because there is no way to tie an individual to his anonymous edits. (There's no way for us to deal with vandals using those proxies, so we block them from editing.) [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 04:55, 7 December 2005 (UTC)
== forces ==
*{{unsigned|71.126.62.100}}
*[[Forces]] or [[Force]]? At least put a question mark at the end, lol--[[User:Aolanonawanabe|Aolanonawanabe]] 23:20, 6 December 2005 (UTC)
*See also [[force (disambiguation)]], or use use [[Force (Star Wars)|The Force]]. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 04:52, 7 December 2005 (UTC)
== Nucleotides ==
What type of bond connects nucleotides? Thanks. --[[User:Sango123|<font color="#00008B">Sango</font>]][[Wikipedia:Esperanza|<font color="#008000">123</font>]] [[User talk:Sango123|<font color="#00008B">(talk)</font>]] 04:36, 7 December 2005 (UTC)
:It depends; was your assignment more specific? :D See our article on [[DNA]] for details—bonds joining nucleotides along one strand of DNA are of one type, and the bonds that join two DNA strands together are of another. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 04:51, 7 December 2005 (UTC)
::You're most likely looking for [[hydrogen bonding]]. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 05:07, 7 December 2005 (UTC)
== US uranium enrichment ==
Yvonne, a reader, has sent the following question to the email help desk.
"Supposedly there is only one company in the USA that is allowed to enrich uranium and can you tell me their name? They are a publicly traded company. I am doing stock research. Thank you and best regards."
Thanks for any assistance you can give her. [[User:Capitalistroadster|Capitalistroadster]] 04:57, 7 December 2005 (UTC)
:[[United States Enrichment Corporation]], which was privatized in the 1990's. At the moment, they still use the high-cost gaseous diffusion process for [[isotope seperation]], but they are apparently planning to build a centrifuge plant. See their website for details. I don't know whether there's any rule that says other companies couldn't get a license to start up an enrichment plant, but there would be very, very high regulatory hurdles to climb. --[[User:Robert Merkel|Robert Merkel]] 05:08, 7 December 2005 (UTC)
== Spell checking ==
Which [[algorithm]]s are most commonly used by commercial [[spell checker]]s, and what does [[aspell]] use? {{User:Eequor/Signature/Syllabic}} 05:41, 7 December 2005 (UTC)
:My guess would be that they perform [[binary search]] through the "dictionary" until the word is found or not found. As for finding the suggested correct spellings, I don't know, but whatever it is, it isn't very good. --[[User:YixilTesiphon|YixilTesiphon]] <sup>[[User talk:YixilTesiphon|Say hello]]</sup> [[User:YixilTesiphon/Wikiproject Article Review|Consider my Wikiproject idea]] 05:49, 7 December 2005 (UTC)
== Phalaenopsis orchid self-germination ==
Reader Andy has sent the following e-mail to the Wikipedia help e-mail desk.
"My [[phalaenopsis]] orchid is doing quite well and I was wondering how to
go about growing new plants by either forcing a keiki or by self
germination and growth on a nutrient gel."
I was able to help with information about the keiki but would be grateful if you could help out with information on self-germination. [[User:Capitalistroadster|Capitalistroadster]] 06:24, 7 December 2005 (UTC)
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