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December 29

Electronic locator

Hello. I'm thinking of taking my little nephew out to play in a small wood (without any streams or water) and it seems likely that he'd want to run off and play hiding games. Perfectly natural, and good fun, but I'd feel more comfortable if I could 'tag' him in some way to make him easy to find quickly if need be. I'm imagining something small that straps to the wrist, that would feedback to something small I kept. Perhaps like 'homing beacons' in old spy dramas, with a little screen that shows roughly where he is and how far away. Or maybe audio feedback like a metal detector. I'm sure such things must exist. Any suggestions?

I'd even welcome suggestions on how to make my own, although I'd need a link to a good walkthough if it involves circuitboards. 86.176.48.114 (talk) 01:11, 29 December 2009 (UTC)[reply]

Here is an external commercial link you might try. 71.100.6.153 (talk) 01:29, 29 December 2009 (UTC) [reply]

Thanks. In forming my question (and thinking of an appropriate title) I actually gave myself some good search terms to find a few in the UK. I've got one that looks likely, although it is very expensive considering I'm not sure how often I'd use it. It's similar to the ones you've linked to, but a bit more multipurpose. I'm still open to suggestions for something simpler (cheaper), although I'm slightly tempted to buy the one I've found just for the "we're living in the future" feel of it. 86.176.48.114 (talk) 01:36, 29 December 2009 (UTC)[reply]

A key chain whistle might be a decent low tech solution provided the nephew is within a certain minimum radius. Noodle snacks (talk) 05:40, 29 December 2009 (UTC)[reply]

That's true, assuming he hasn't knocked himself out with a rock :) It's one of those silly things where if he were my child I'd be willing to take the risk, but since he's my brother's I feel like I have to be more sure. Thanks: maybe I'll get him blowing the whistle for fun before releasing him, and hopefully he'll enjoy the loud noise enough to keep doing it from time to time, even if he doesn't think he's lost. Makes for a good game of fox and hounds. 86.176.48.114 (talk) 14:31, 29 December 2009 (UTC)[reply]

How about along piece of string tied between his wrist and yours? Not electronic but simple! —Preceding unsigned comment added by PeekyWeedia (talk • contribs) 02:55, 31 December 2009 (UTC)[reply]

Weird phenomonon

There are cirus clouds in my area (clayton,nm,USA) and right by the moon there is this gaping hole in the clouds. What is this?Accdude92 (talk to me!) (sign) 03:25, 29 December 2009 (UTC)[reply]

It's not a hole. It's an illusion. You see the clouds only because of the light from the ground. The moon is so bright, that all you see is the moon, and not the light from the ground reflecting on the clouds. If you watch for a while, you might be able to see a slight fuzziness over the moon from the clouds. It's much easier to see if the moon is not full. Ariel. (talk) 04:48, 29 December 2009 (UTC)[reply]

but its a huge hole!Accdude92 (talk to me!) (sign) 04:57, 29 December 2009 (UTC)[reply]

Does it look like this? HERE --220.101.28.25 (talk) 07:38, 29 December 2009 (UTC)[reply]

Yep!Accdude92 (talk to me!) (sign) 15:30, 29 December 2009 (UTC)[reply]

It's not a hole. it's a halo. Dauto (talk) 17:20, 29 December 2009 (UTC)[reply]

There is one that can be seen around the Sun too, but it's really bright looking in that direction, so that is not recommended. I think it is some prismatic effect that comes from any light source. Look at a candle flame; it has a halo, and I think that's the same principle.--Neptunerover (talk) 02:41, 30 December 2009 (UTC)[reply]

I don't think so. I don't know what you are talking about but halos are caused by ice crystals floating in the atmosphere. Not something one would expect to happen around a candle flame inside a home where it is nice and warm. Dauto (talk) 14:03, 30 December 2009 (UTC)[reply]

I think Neptunerover is just letting us know that their eyes are not perfectly round: I'm blanking on the term. When your eyeballs are a slightly different shape and it affects your vision in various minor ways and has to be factored into your lenses (if you otherwise need glasses)? 86.176.48.114 (talk) 23:05, 30 December 2009 (UTC)[reply]

Wait a minute, are we talking glasses on or off here? For me there's a huge difference. Since that case, my previous input may be little more than a curiosity here. --Neptunerover (talk) 23:44, 30 December 2009 (UTC)[reply]

Astigmatism? I don't think that would cause halos around candle flames. I have an astigmatism and I sometimes see such halos and sometimes don't - it seems to happen when my eyes are watering for some reason. Presumably it is to do with the light being refracted by the tears in my eyes. --Tango (talk) 23:34, 30 December 2009 (UTC)[reply]

As others have suggested, this 'hole' is part of an atmospheric halo phemomenon, caused by ice crystals floating in the apparently clear or near-clear sky. As in this [1] diagram (on a generally relevant site), when a bright halo is formed in a circle around the Sun or Moon it is composed of light from within the circle that has been refracted, resulting in the circle's inner area being a littler darker than the sky overall. This is very hard to see around the very bright Sun (though a similar effect called Alexander's band is more observable outside an ordinary rainbow opposite the Sun). When the dimmer Moon is in the night sky, the effect is more obvious. 87.81.230.195 (talk) 15:52, 30 December 2009 (UTC)[reply]

On Spaceweather.com, a recent entry said to look out for moon halos as the atmospheric conditions were right for them. There's also a full moon right now and this contributes to the halos. ~A H 1^(TCU) 00:36, 1 January 2010 (UTC)[reply]

Sulfuric acid and wax

Will sulfuric acid dissolve any kind of wax? If so, which kinds does it dissolve most efficiently? 69.111.79.27 (talk) 04:47, 29 December 2009 (UTC)[reply]

Sulfuric acid will not, but Magic acid and Superacid will. Ariel. (talk) 04:50, 29 December 2009 (UTC)[reply]

Depends on what you mean on "wax" I guess. Waxy substances with double bonds in them (ester/amide type groups, alkenes) or aromatic groups may react and "dissolve". John Riemann Soong (talk) 06:02, 29 December 2009 (UTC)[reply]

Also depends on what you mean by "dissolve". Magic acids will outright protonate saturated compounds and that proton will stay on, helping remain the compound remain "dissolved". With sulfuric acid, it might catalytically put a proton on an unsaturated molecule, ripping it away from a hydrophobic crystal lattice into solution, and may or may not catalyse some sort of reaction (e.g. hydrolysis, sulfonation). But then the proton comes off and the product is insoluble, giving you a sort of colloid rather than a real solution. (After neutralising the acid, you can collect the precipitate by letting it sit and/or centrifuging it). John Riemann Soong (talk) 07:01, 29 December 2009 (UTC)[reply]

are hydride donors compatible with thionyl chloride?

Just checking ... replacing -OH (or -COOH) with -H isn't really a possible as a one pot synthesis with these reagents right? If it is possible, is using Tris(pentafluorophenyl)boron (+ n-butyl silane), are there any additional advantages besides convenience? (Wondering about cost, yield/efficiency, messiness, industrial production, all that jazz, etc.) John Riemann Soong (talk) 05:03, 29 December 2009 (UTC)[reply]

Reason for the variable names in the Lagrangian

The formula is L = T - V where T is kinetic energy and V is the potential energy. What do these symbols stand for? Why these instead of $E_{K}$ and $E_{U}$ or K and U like normal? (And why U?)-Craig Pemberton 06:30, 29 December 2009 (UTC)[reply]

T and V are normal. Dauto (talk) 06:38, 29 December 2009 (UTC)[reply]

They also show up in Hamiltonian mechanics as well. However, the OP is not the only one to note the difference in usage. The article Lagrangian mechanics notes that Lagrangian uses T & V where other contexts use K and U. Not sure why two contexts are using 2 different sets of variables for the same thing, except to note that K and U are just as arbitrary as T and V, so I don't really see why either makes much of a difference. --Jayron32 06:42, 29 December 2009 (UTC)[reply]

I'm not saying that one is better than the other, just wonder what the etymologies and historical differences might be.-Craig Pemberton 06:44, 29 December 2009 (UTC)[reply]

What is Quantum Action?

I'm trying to understand Feynman's Path Integral Formulation, but I don't seem to get what is quantum action. Can anyone please kindly explain it to me?~~The Successor of Physics~~ 07:11, 29 December 2009 (UTC)[reply]

See Action (physics). Quantum action just means that the correct value is obtained by integrating energy of the Lagrangian with respect to time (as in classical action), but where the Lagrangian is quantized and calculated according to the rules of a particular quantum mechanical system. As far as what action is, it is simply a physical parameter of the system. Action represents the difference between kinetic and potential energies. According to the Principle of least action (which is essentially just an empirical observation that is mathematically consistent as a generalization of classical mechanics), a system prefers to obey motions such that action is minimized; Feynman's approach solves the system according to a path integral representation of this principle. Nimur (talk) 08:14, 29 December 2009 (UTC)[reply]

I still don't get the idea of the physical interpretation of quantum action, and how do you calculate it?~~The Successor of Physics~~ 12:16, 29 December 2009 (UTC)[reply]

How familiar are you with canonical quantization and classical classical action? Dauto (talk) 14:31, 29 December 2009 (UTC)[reply]

You calculate quantum action by integrating the Lagrangian with respect to time. If you don't know how to construct a quantum mechanical system's Lagrangian, then Lagrangian mechanics is the first place to start. Do you have a specific example? Often, the quantum harmonic oscillator is the example problem for such derivations. You can construct a quantized lagrangian for that system, and then integrate it. As I alluded to above, "intuition" is not necessarily going to take you far here - first, the classical formulation of action is fairly abstract. You have to gear your mind to think in terms of energy - I imagine little "gas tanks" full of Kinetic and Potential energy, and as the system changes state in state space, gas pours from one tank to the other... and then you want to minimize the Lagrangian as you integrate with respect to time. (See, the intuition is a little weird in even the classical case). Then you quantize the gas tanks... (energy levels) - so you can't pour energy between the two tanks continuously - but must transfer energy in discrete amounts, with quantities determined by the present quantum state space representation of the system. Nimur (talk) 01:00, 30 December 2009 (UTC)[reply]

Is this plausible?

http://www.snopes.com/college/risque/telltale.asp

Can sperm really last that long in the mouth? Are they easily visible in high school microscopes? Are they easily identifiable as sperm cells (easy enough for high school students to recognize them without the lab assistant's help)? --99.237.234.104 (talk) 09:36, 29 December 2009 (UTC)[reply]

How long are you talking about? You don't know what she was doing right before class, do you? Spermatozoa would be visible in high school micropscopes but may not be readily identifiable by the inexperienced observer because they're quite small, the head being about 1/3 the diameter of your average red blood cell, and quite considerably smaller then squamous cells, which you see most of in a buccal smear. Depending on how long they were there for, there'd be a variable degree of degradation, and the background may also include food residues, yeasts, bacteria, degenerate squames and other debris that would also make spermatozoa hard to identify, unless there was a huge number of them. Let your imagine take that where it will... Cheers! Mattopaedia ^{Have a yarn} 15:01, 29 December 2009 (UTC)[reply]

If not too much time had passed, the wiggling motion would be distinctive and highly noticeable, compared to the other things usually found in buccal swabs. Edison (talk) 21:49, 29 December 2009 (UTC)[reply]

Yes, but only in a fresh smear. I omitted to mention this because fixation in alcohol and application of any stain (for visualisation and infection control purposes) would, obviously, stop the wriggling. Mattopaedia ^{Have a yarn} 11:43, 31 December 2009 (UTC)[reply]

Autonomous Intelligence

What would happen if the mighty WikipediAI (meaning a Giant Knowledge Computer able to think Autonomously -- the GWACK or WikiGACK, or..) that we are all creating here were to gather all this physical sciences information together and from that figure out a solution to 'quantum gravity' and maybe some other things. Could WikipediAI win the Nobel Prize? --Neptunerover (talk) 09:43, 29 December 2009 (UTC)[reply]

Uh..., I think you should put this question on another reference desk like the computing one.~~The Successor of Physics~~ 12:11, 29 December 2009 (UTC)[reply]

Nobel Prizes are awarded to persons who have "bestowed the greatest benefit on mankind". Nominated persons must be alive. This would seem to rule out any kind of machine. SpinningSpark 12:41, 29 December 2009 (UTC)[reply]

So I guess then it would need to be awarded to all the persons who contributed to the Wikipedia knowledge space. Even better. --Neptunerover (talk) 12:57, 29 December 2009 (UTC)[reply]

There is a big difference between intelligence and knowledge. Wikipedia has great knowledge, but no intelligence. --Tango (talk) 13:46, 29 December 2009 (UTC)[reply]

I was wondering about that very paradox earlier: How much knowledge does it take to be wise? --Neptunerover (talk) 00:56, 30 December 2009 (UTC)[reply]

What paradox? Intelligence and knowledge are just different things. Wisdom is, again, a different thing. They are related, certainly, but they are different. --Tango (talk) 02:15, 30 December 2009 (UTC)[reply]

I guess the paradox is for people who confuse them, since neither leads to the other, although when used together, they work very well. --Neptunerover (talk) 02:29, 30 December 2009 (UTC)[reply]

I've been sitting outside the university's library for years, and I still haven't seen it come up with the solutions to any problems. Why should we expect an electronic medium for storing bits to suddenly be more inspired than a paper medium? In any event, Wikipedia expressly not a venue for original research. TenOfAllTrades(talk) 14:33, 29 December 2009 (UTC)[reply]

But if Wikipedia could be proved as the epicenter of a vast paradigm shift, then nobody would ever be able to claim the idea was originally theirs. I mean not a one here among us does not stand on the shoulders of giants. Without those who amassed all this knowledge, we would not be able to put it all together here. What if by putting it all together in this form (the transfer of the printed books to this medium), it just comes together all by itself, and tah dah! --Neptunerover (talk) 00:56, 30 December 2009 (UTC)[reply]

On my user page, some time ago, I put a little quip about Wikipedia being an inevitable part of technical and social progress. This free internet-based encyclopedia is simply the most easily-recognized form of the larger trend towards free and democratic information that is mobilized by technology. This idea of a large, technology-driven collaborative information platform is not new:

H.G. Wells predicted it in 1937
Vannevar Bush predicted it in 1945
Doug Engelbart demonstrated one in 1968

Wikipedia is part of a larger trend towards free free information. In my opinion, it is the inevitable result of free communication. The fact that it manifested as an internet-connected set of digital computers driven by user-generated content is simply because that is the state of technology that coincided with the present era of free information interchange. Earlier forms (library, university) were limited by technology (notably, the ability to transfer and copy information quickly, easily, and reliably, across large geographic barriers). We can only speculate what future forms the technology may manifest in - but I think the trend is definitely moving towards symmetric information exchange amongst a larger percentage of the global community. It is becoming increasingly impossible to prevent the free flow of knowledge - information will be free. Nimur (talk) 01:12, 30 December 2009 (UTC)[reply]

That information transference you mentioned is exactly it. It was always so slow before to look up different things.
And as far as any theories that may spring from this knowledge collection being considered as 'original research,' is that even relevant considering the only research done consists of going through things that have already been thoroughly researched by others? A theory comes before research. Research gets done by scientists, which is done outside of a computer, or at least outside of Wikipedia.--Neptunerover (talk) 01:40, 30 December 2009 (UTC)[reply]

What if the input does not compute? What if various articles are in conflict with each other, and WikiAI is able to pinpoint the areas of conflict while providing a solution? Would anybody listen? Or would they all point at Wikai and say, "stop trying to think; you're only a computer!"? Is there no original theorizing on Wikipedia either? I mean, what better is there than a free theory? There's none of that having to wait around for peer reviews and being accepted for publication to selected people who then get to interpret the theory for us because it's written so complexly, and then pretty much any new technology arising from the theory is like a trade secret kept from humankind. I mean, who does not like to think for themself? (even when making up new words that should be easily understood, even though such words may not be authoritarian enough for certain individuals who may get hung up on minor insignificant details.) --Neptunerover (talk) 02:20, 30 December 2009 (UTC)[reply]

It is not that uncommon for articles to conflict with each other. If anything it can stimulate the reader to further 'research' for more reliable or more authoritive sources. They can even get the 'right' answer, and correct the articles, thus becoming an editor! There is no "WikipediAI,...GWACK or WikiGACK, or..)" unless you are thinking the Internet may become "self-aware"! That would be a problem, turn off the web and a lot of industry, communications etc would simply stop!
One reason OR and personal theories are not allowed is there is already a great deal of fringe/pseudo 'science', and outright garbage being put onto Wikipedia. A lot of effort is spent stopping it, correcting it, removing it and discussing it where there is basis for debate.(IMHO) --220.101.28.25 (talk) 03:01, 30 December 2009 (UTC)[reply]

You point out a problematic common assumption there, which is that a "self-aware" Internet, etc. would be unfriendly toward humankind. That's only what happens in the scary movies. There must be a movie out there where the computer realizes it's only hope is to help humankind. Who but a maniac would wish destruction of their maker? --Neptunerover (talk) 03:39, 30 December 2009 (UTC)[reply]

Neptunerover, please go and watch that movie instead of using the Ref Desk as a soapbox for endless "What if..." speculative debate. Tad-dah. Cuddlyable3 (talk) 18:42, 30 December 2009 (UTC)[reply]

Sorry, I don't mean to "soapbox" on your page. You could always just not answer me. That sometimes makes a point. What was the good computer movie anyway? Actually, never mind, there's probably a better desk for that question, or I'll just see if I can find it myself. Thanks anyway. --Neptunerover (talk) 01:15, 31 December 2009 (UTC)[reply]

Actually Cuddlyable3, I am sorry because I generally do my best to avoid biting back. It's something that never makes me feel good. So this then is my attempt to make myself feel better, since how you feel is of course up to you. Sorry.--Neptunerover (talk) 03:21, 31 December 2009 (UTC)[reply]

← I think this all went a little off-topic here. When answering earlier I forgot that Wikipedea does have 'bots' that automatically revert vandalism(ClueBot), sign when editors forget to (SineBot) etc. NeptuneRovers' last question was "Could WikipediAI win the Nobel Prize". I suppose that depends on the rules that the Prize is awarded under. I think it may be a while before the question becomes relevant! As SpinningSpark pointed out it is awarded to a person, this issue was covered in Asimovs' book Bicentennial Man

Our fear of a 'superior'(?) intelligence possibly comes from what has happened when 'modern' culture has encountered 'primitive' over human history. In many/most? cases the 'primitive' culture has not fared well. In this case it could be Humanity. If our AI was like us, it might not be very nice to us (speculation of course). Or its ideas of good may not equate to ours.

Asimovs' Three Laws of Robotics, may give an insight. These laws, on the surface clear cut and foolproof, have many problems or 'grey' areas that Asimov himself often used as the crux of his stories. People have already died as a result of computer/programming bugs, sometimes combined with mechanical failures and human designed flaws. Remember modern airliners are now often flown by the computer, and they have got it wrong and caused crashes!.--220.101.28.25 (talk) 12:57, 1 January 2010 (UTC)[reply]

The current dangers that Wikipedia is facing is not any chance of it becoming self-aware, but political, ideological or financial interests hiring or motivating a lot of people to push their POV. About self-awareness, the software of this website is only a text editor and search engine, without any neural networks or genetic algorithms to allow it to learn or evolve. The text on the pages of Wikipedia might be used to teach an AI (a chatbot, for example), but any book or other website containing enough text in some language would be similarly useful. --79.116.79.117 (talk) 23:56, 1 January 2010 (UTC)[reply]

Death by starvation

Hi

1.How does a pathologist know when a human being has starved to death?

2.Many times in movies we see people getting either shot, stabbed or killed in some way where they die with their eyes open. In real life what are some of the reasons that cause people to die with their eyes open (Sometimes their mouths as well)?

3.I hope I don't sound stupid by asking the following question: Is there a way of measuring the intensity of physical pain experienced by human beings and if so can you tell me which pain is worse between: A man getting hit or kicked between the legs and a female giving birth.

Thank you, NirocFX

To answer number 1, a pathologist would examine the stomach and gut contents of the corpse, and if there is little or no food still in there at death then starvation would be an appropriate diagnosis, especially if associated with emaciation. With number 2 (although there is no OR in this statement), it is perfectly normal for people to die with their eyes open, unless they have died in their sleep in which case their eyes would be shut. Although I haven't actually witnessed a death yet, I have had to shut the eyes of people who have recently died. A comment on number 3: they tell me that passing a kidney stone is more painful than either of the two examples given. I can believe that! --TammyMoet (talk) 10:47, 29 December 2009 (UTC)[reply]

Our article on pain doesn't cover intensity, but a recent section of the talk page suggests that it will do soon. We have an article on the Dolorimeter, which is "an instrument used to measure pain tolerance". According to the article, dolorimetry has been defined as the measurement of pain sensitivity or intensity. Mitch Ames (talk) 12:53, 29 December 2009 (UTC)[reply]

See also Pain scale, of which a nice example is the Schmidt Sting Pain Index. AndrewWTaylor (talk) 12:59, 29 December 2009 (UTC)[reply]

Further OR: I have heard from people who have experienced both that giving birth is more painful than breaking a leg, although (according to people I know who have given birth more than once) you forget how bad it was, somehow, until such time as you are giving birth again. At which point you think "Shit! I remember this!". In which case, you'd need to make sure you measured the pain at the time, not as reported afterwards. In any case, ask a man who has experienced both whether getting hit in the groin or breaking a leg was more painful, and you might be closer to an answer. 86.176.48.114 (talk) 14:18, 29 December 2009 (UTC)[reply]

I have to disagree with TammyMoet's guidelines for the diagnosis of starvation as cause of death. While it is true that the stomach and digestive tract would be devoid of food, that is certainly insufficient evidence. The stomach clears quite quickly after a meal; it will be empty again less than six hours after the last meal. The rest of the system is cleaned out in a day or two. While a lack of food residue anywhere in the digestive tract would (likely) be indicative of an abnormally long period without eating, it is by no means sufficient basis for a diagnosis of starvation. An initially heathy individual of normal weight can often survive for one to two months without food (as long as sufficient fresh water is available).

The Handbook of Forensic Pathology offers a brief description of the symptoms of death by starvation: [2]. Perhaps the most important clue is a virtually complete absence of body fat — the body will consume its own energy reserves before dying of starvation. TenOfAllTrades(talk) 15:06, 29 December 2009 (UTC)[reply]

(ec)

I can discusss the death bits a bit more - that's my thing -, the pain stuff I can't really add much more to. Fatal starvation is given as a cause of death after considering the known, reported circumstances of the death, such as by Police, attending medical staff, carers and family, in combination with examination of the body. The body externally typically shows severe emaciation, almost literally a "Skin and bones" appearance. There are also more subtle changes also seen in the hair and nails. The internal examination usually doesn't add a great deal to the findings, other than noting marked wasting of musculature, a lack of any fatty layer in the omentum and mesentery and general organ atrophy. That the intestinal tract is empty doesn't really mean that much in itself, it simply means the person did not eat for a few days to a week, but death by starvation takes much longer, unless you dehydrate as well. Most people die with their eyes open. The mouth can gape a bit too. Even when you die in your sleep, your eyes still can open a bit because keeping your eyes closed is an active process (that is, a nerve stimulates the lid muscles gently to stay closed - not like dropping a sash window). Funeral directors typically use some means (such as glue or sutures) to keep the eyes and mouth closed on bodies for viewing purposes, so the deceased appears more like they're sleeping than actually dead, because its easier for our psyches to deal with death that way. HNY! Mattopaedia ^{Have a yarn} 15:21, 29 December 2009 (UTC)[reply]

The absence of body fat seen, in simple starvation death due to lack of access to adequate nutrition, can be a secondary manifestation of cancer, anorexia, COPD or diabetes. Edison (talk) 21:48, 29 December 2009 (UTC)[reply]

Would starvation be determined by extraordinarily low blood sugar levels? Googlemeister (talk) 14:52, 30 December 2009 (UTC)[reply]

Administration of excess Insulin would be a more likely cause of extremely low blood sugar levels, and would not constitute starvation. See Hyperinsulinemic hypoglycemia. During prolonged food deprivation, the body would slowly digest the fat and then the muscle tissue, with it being converted eventually to glucose. See [3] Some unfortunate people suffer from hypoglycemia between meals even when an adequate diet is provided, and even when they are obese. Others apparently can maintain near normal glucose during prolonged food deprivation, until the fat and muscle are depleted.Eventually, the body would not be able to maintain normal blood sugar levels. One reference [4] says that starving deer eventually have low blood sugar which causes them to tremble and have trouble standing. That book says that a red color in the bone marrow of the deer's leg bone is diagnostic that it died of starvation, even if only bones are left. No idea if that applies to humans. thEdison (talk) 18:08, 30 December 2009 (UTC)[reply]

See marasmius and kwashiorkor.-Craig Pemberton 23:32, 30 December 2009 (UTC)[reply]

What do mushrooms (Marasmius) have to do with starvation???? Edison (talk) 02:44, 31 December 2009 (UTC)[reply]

Marasmus, I think. Tevildo (talk) 10:14, 31 December 2009 (UTC)[reply]

Blood sugar levels can't be reliably assessed post mortem. The action of bacterial fermentation in blood and body fluids produces artefactual results. Glucose estimation can be performed on vitreous humor post mortem, however this is more useful for high-glucose conditions such as diabetic ketoacidosis, and low levels of glucose in the vitreous are non-specific. I don't know about the red colouration of bone marrow idea - bone marrow examination is not routinely performed in most autopsy cases, and usually not when starvation is the suspected cause of death. Bone marrow examination is usually only done for suspected cancer. That said, I'd imaging that red colouration of the marrow would be difficult to distinguish from that caused by the normal presence of blood in the marrow, in humans at least. Mattopaedia ^{Have a yarn} 11:58, 31 December 2009 (UTC)[reply]

In response to question three: the first one is extremely variable, while the second one depends on factors such as duration I think. ~A H 1^(TCU) 00:30, 1 January 2010 (UTC)[reply]

pHILOSOPHY

From the writtings of Plato, explain idealism in terms of its metaphysics, epistemology and axiology, in relation to his narration of the myth of the Winged Horses. —Preceding unsigned comment added by 217.194.149.228 (talk) 10:51, 29 December 2009 (UTC)[reply]

Please do your own homework.

Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. Please see our relevant articles: Plato's writings & Idealism. Ks0stm ^(T•C•G) 11:03, 29 December 2009 (UTC)[reply]

217: am I wrong or you are not even able to restate your question so as not to make it immediately recognizable as homework? Besides, it seems you also have a difficulty in placing your query in the right Ref/desk (it's not here, it's not even the Computing/Desk). The best suggestion I can sincerely give you is to reconsider attending your school. You may live without Plato. --pm a (talk) 13:34, 30 December 2009 (UTC)[reply]

I would be reluctant to recommend a philosophy course, even at the most introductory level, which decscribed Plato's philosophy as "idealism". Unless the question is asking the OP to explain the _differences_ between Platonism and idealism, which I somehow doubt. :) Tevildo (talk) 18:14, 30 December 2009 (UTC)[reply]

I thought the question was suggesting that Plato held a view on idealism (and hence, wants you to explain how Plato describes idealism) rather than that Plato espoused idealism. Perhaps it is referencing the Chariot Allegory? Or something else which can be found in Platonic epistemology. Either way, the person asking this question would be best served by reading the resources they have been given, to find clues as to the expected answer. This sounds like the sort of task that is set to improve someone's skills at finding and extracting relevant information, and synthesising it into a new piece of writing. I can see all sorts of ways in which carrying out this task properly could improve someone's ability to think and work on any manner of topic. That they are learning about Plato is only relevant in that they might be interested in him or his writings, providing motivation. 86.176.48.114 (talk) 19:06, 30 December 2009 (UTC)[reply]

Does philosophy really belong on the science reference desk? ~A H 1^(TCU) 00:25, 1 January 2010 (UTC) [reply]

Plausibly yes, although in my experience philosophers get nervous when someone with more 'scientific' training joins a discussion on philosophy. "But that's just silly. Of course you can prove/disprove it." *scribbles* 86.176.48.114 (talk) 04:06, 1 January 2010 (UTC)[reply]

We need a reference desk specifically for philosophy, psychology etc. I'll make my case and discuss this later. ~A H 1^(TCU) 03:04, 2 January 2010 (UTC)[reply]

The Truman Show.

Would the artificial environment Truman was held captive in be viable with present day technology? Trevor Loughlin —Preceding unsigned comment added by 80.0.98.82 (talk) 15:23, 29 December 2009 (UTC)[reply]

Do you mean, could you simulate living in an artificial environment good enough so that someone inside couldn't tell they were not actually "outdoors" ever? It's probably possible though it would be difficult—you'd have to make the enclosure VERY large in order to make it really look like sky, clouds, etc. Of course, Truman never lived outside of the enclosure, so maybe he just wouldn't know the difference—what a "real" cloud looked like, etc. --Mr.98 (talk) 15:35, 29 December 2009 (UTC)[reply]

Biosphere 2 may be of some interest. -- Coneslayer (talk) 16:36, 29 December 2009 (UTC)[reply]

Yes, it's called a movie studio, but this only works because we see movies in 2D. If Truman had only one eye he could have been fooled for a while; with binocular vision the limited extent of his confines should have been obvious to him.--Shantavira|^{feed me} 16:41, 29 December 2009 (UTC)[reply]

Perhaps see Plato's Cave. I think most people could go their whole life accepting oddities in reality without questioning them. It took humanity many thousands of years to figure out what stars were, and that's without an active intelligence working against any proto-scientists' questions. Imagine if every time Galileo said "hmm, that's funny ..." they sent Laura Linney in to distract him with female pulchritude. --Sean 19:04, 29 December 2009 (UTC)[reply]

I think you could build something that would fool someone who spent their entire life living inside of it - simply because they wouldn't know any better. But it would have to be an ungodly large dome. The necessity of providing enough sunlight from a reasonably small bank of floodlights that could be winched over the dome at the right speed would be tricky - and finding some central point from which to project a cloudscape onto the dome without any risk of intervening shadows would also be rather hard. On balance, I think the answer has to be a cautious "No"...depending on the restrictions you place on the system because Truman doesn't know any better. After all, if you just built a small area without the dome (Why do you need that anyway?) and told the newborn child that this was all of the world - carefully censored everything he read and watched...how could he know that the world wasn't really 10 miles across? SteveBaker (talk) 19:45, 29 December 2009 (UTC)[reply]

Whoever asked this question, I certainly hope you don't think you are being held captive and watched on TV, which could explain your concern over the feasibility of such an intricately executed deception actually occurring. I say, if you're gonna write a movie, go for it, otherwise, quit acting like you're the center of the universe, for the love of reason! --Neptunerover (talk) 02:54, 30 December 2009 (UTC)[reply]

It's a perfectly reasonable question, and the OP does not suggest at all that he is being held captive. The question was likely motivated by ordinary curiosity. I would suggest that you assume good faith and avoid personal attacks. -- Coneslayer (talk) 14:11, 30 December 2009 (UTC)[reply]

I certainly meant absolutely no offense to the OP, and I apologize to them if my comment caused them any. I was only considering a possible motivation for such a query being posed, and my comments then were meant only as a response to someone who may feel that they are in such a situation, just in case. I mean, you've heard the term, "seek and you shall find," so I felt perhaps a wake up could be helpful to someone who has gone seeking conspiracies or whatever center of the universe trip they might be on. And if not the OP, then who knows who else may come across this and be caught in such a delusion of being watched, which is not an uncommon delusion for the delusional, as far as I know. --Neptunerover (talk) 01:00, 31 December 2009 (UTC)[reply]

How does snorting vodka work?

i wanted to know how snorting vodka worked, i know it bypasses the digestive system and enters pretty much straight in to the blood stream, i wanted to know about the process(s) in which this happens. Many thanks, Mattymiles2009 —Preceding unsigned comment added by Mattymiles2009 (talk • contribs) 16:26, 29 December 2009 (UTC)[reply]

I don't get it -- why not just gurgle it in the front of your mouth? (Well it'll taste horrible, but better than vodka up your nose!) Alcohol is water soluble and will basically diffuse into mucous membranes into the bloodstream. John Riemann Soong (talk) 18:40, 29 December 2009 (UTC)[reply]

See Nasal administration. I wonder about long-term effects, though. 88.242.146.177 (talk) 19:16, 29 December 2009 (UTC)[reply]

I once accidentally nasal flushed a mouthful of vodka while laughing. It was roughly equivalent to lighting my sinuses on fire and I wouldn't recommend it to anyone. If you wish to get drunk without having to worry about barfing, there are other methods of imbibing the alcohol. Be warned, however, that bypassing your upper digestive system increases the risk of acute alcohol intoxication and associated problems (including death). Matt Deres (talk) 19:44, 29 December 2009 (UTC)[reply]

I wonder if the original poster is thinking of inhalation of vaporized or misted ethanol, as with alcohol without liquid systems? TenOfAllTrades(talk) 20:16, 29 December 2009 (UTC)[reply]

Vodka introduced by an Enema passes immediately into the bloodstream. Cuddlyable3 (talk) 22:08, 29 December 2009 (UTC)[reply]

I've never heard of snorting vodka, and I doubt it's something people actually do (more than once). A "snort" of a drink is a mouthful, but it's not meant for your nose. --76.182.94.172 (talk) 23:49, 29 December 2009 (UTC)[reply]

I've snorted spirits at parties on a couple of occasions (once vodka, once Jack Daniels). I can't really tell you if it made me drunk any quicker, as I was already pretty far gone when I did it. I remember that it made my eyes water and my nose felt 'thick' on one side for half an hour or so after. It did sting at the time - but it wasn't excruciating, as far as I recall. My worst drinking game-related experience ever was when a bunch of us were drinking with this crazy ex-sailor guy and we were doing what he called the 'Malawi bumfuck' (no, it's not a deviant sexual act - honest!) - shot of tequila, snort some lemon juice cupped in the palm of your hand, then dip both your fore and index fingers in salt and rub them in your eyes. Note: kids, don't do this unless you're really concerned about losing face in front of your casual drinking buddies - and even then, do think it over a bit. No, really - I wouldn't recommend it. --Kurt Shaped Box (talk) 00:45, 30 December 2009 (UTC)[reply]

A word of caution to those kids who might be inspired to try the above at home: note that Kurt Shaped Box is now an avid gull enthusiast, possibly as a side effect of the above experience. This could happen to you! Nimur (talk) 01:17, 30 December 2009 (UTC) [reply]

What really happened is I heard that gulls could desalinate through the mucous membranes of their faces. I wanted to see if I could do that too... --Kurt Shaped Box (talk) 02:11, 30 December 2009 (UTC)[reply]

All the nice gulls love a (crazy ex-) sailor. Cuddlyable3 (talk) 18:28, 30 December 2009 (UTC)[reply]

Rate Law for Heterogeneous Reactions

Hello. Do rate laws include solid reactants if they are not to the zero order? Is the concentration of the solid reactant irrelevant to the rate law since solids have fixed densities? Thanks in advance. Have a happy new year. --Mayfare (talk) 18:18, 29 December 2009 (UTC)[reply]

Are you talking about reactions within a crystal lattice (or within the solid phase), or are we talking about solid-liquid interactions here? John Riemann Soong (talk) 19:20, 29 December 2009 (UTC)[reply]

Reply to OP. Rate law depends on Activity of the substances, and to a first approximation molar concentration does a reasonable stand-in for activity. Now, here's the deal, changes in rate thus depend (in our approximation) on changes in concentration. Solids certainly have a concentration (basically the molar density, or number of molecules per unit volume), however solid concentration does not vary with with amount. If I have a gas in a container, and remove 1/2 of the molecules, the concentration of the gas drops by 1/2, since the space between the gas molecules will be greater. The deal with solids is, the molecules are held into contact via intermolecular forces, so in a solid, if I remove 1/2 of the molecules, the remaining molecules do not spread out to fill in the missing space. As a result, the remaining solid maintains a constant concentration regardless of the amount of substance.

In conclusion, because solid concentration does not change as it is used up (as a reactant) or created (as a product), then the amount of a solid does not readily affect reaction rate. In the case of gases, or aqueous solutions, when the number of molecules change, the remaining molecules move closer together (or farther apart), which results in more (or less) collisions, which affects how fast the reaction proceeds. So no, the amount of a solid does not affect reaction rate, but gases and aqueous substances do. --Jayron32 20:25, 29 December 2009 (UTC)[reply]

I think surface area is actually a factor though -- if it's a solid reagent suspended in liquid (e.g. magnesium turnings, or random emulsified reagents), the liquid can only react at the interface, and as the reaction proceeds, the surface area to volume ratio expands, so the reaction rate would actually increase? John Riemann Soong (talk) 22:14, 29 December 2009 (UTC)[reply]

Costs of test devices

About how much would a scintillation counter cost? How about a Geiger counter? Where could I buy/How could I make these? THX --76.230.231.84 (talk) 18:26, 29 December 2009 (UTC)Tim[reply]

Edmund Scientific has Geiger counters ranging from US$269 to $899. -- Coneslayer (talk) 18:31, 29 December 2009 (UTC)[reply]

You can buy much cheaper, mostly Russian, instruments on eBay but I wouldn't like to say how accurate they are and a lot of them are marked in Cyrillic characters. Also, what do you want it for? if you are looking for something that will tell you if you are safe to go outside after a nuclear attack/accident most of the instruments for sale would be useless. They are too sensitive and max out too early. For this you need something that can measure very large radiation levels, see Civil Defense geiger counters. A meter that is already reading full scale at 1R/hour, where you might get away with spending half an hour outside to put up a radio antenna, cannot tell the difference between that and 100R/hour which has a good chance of killing you. SpinningSpark 19:35, 29 December 2009 (UTC)[reply]

$250 and up seems about the going price for a geiger counter - you can save maybe $50 here by assembling it yourself from parts - but you really need that Geiger–Müller tube and that's maybe $40 to $100 depending on the kind you get - so you won't get much cheaper than that. Depending on what you are trying to measure, you could go 'old-school' and make a 'cloud chamber'. There are lots of sites online that show you how to make one - probably with some dry ice plus some stuff you have lying around the house. This, for example. I suppose you could could go even older-school and consider making a spark chamber - but I don't see any decent instructions for doing that online and they are generally considered obsoleted by the cloud chamber - which is also a lot cheaper and easier to build. SteveBaker (talk) 19:37, 29 December 2009 (UTC)[reply]

female lubrication and mucous membranes

I note that the area around the clitoris is a mucous membrane ... so that makes me ask ... are vaginal secretions evolutionarily related to mucus? Do we have phylogenetic precursors to the use of mucus-like secretions for lubrication? I suppose originally the main advantage conferred was antipathogenic? What about the male? John Riemann Soong (talk)

From Vaginal lubrication: "While plasma seepage from vaginal walls due to vascular engorgement is considered to be the chief lubrication source, the Bartholin's glands, located slightly below and to the left and right of the introitus (opening of the vagina), also secrete mucus to augment vaginal-wall secretions.". --Sean 19:09, 29 December 2009 (UTC)[reply]

Yeah I read that part. Curious about the evolutionary history of this, as well as male secretions. Are the primary secretions (non-augmented) mucus-based, or does it come from blood plasma? Does mucus come from blood plasma? At what stages of the phylogenetic tree do we see mucuslike or plasmalike secretions for lubrication? It prolly starts with the vertebrates (amphibians?), right? John Riemann Soong (talk) 19:17, 29 December 2009 (UTC)[reply]

The plasma in question is blood plasma. Does that have to be made more explicit in the article? Plasma is not mucus-based and does not contain mucin: mucus is a secretion of specialized mucous cells and is not derived from blood. Developmentally, the female Bartholin's glands are equivalent to the male Cowper's glands, which in lower mammals are responsible at least in part for the formation of the copulatory plug. Alas, I don't know how much lower than mammals this goes; I can't imagine fish have much use for the things. - Nunh-huh 19:36, 29 December 2009 (UTC)[reply]

Women generally like it when you note the area around the clitoris. May I recommend some field studies with willing subjects? You may find this to be far more informative than asking questions here. --Jayron32 20:17, 29 December 2009 (UTC)[reply]

^{[citation needed]} Nimur (talk) 01:22, 30 December 2009 (UTC)[reply]

^{[original research?]} seems more appropriate here. Or atleast, more fun! --Jayron32 01:40, 30 December 2009 (UTC)[reply]

^{[clarification needed]} Does small type mean we are whispering? --220.101.28.25 (talk) 02:12, 30 December 2009 (UTC) [reply]

It means that size is important. Cuddlyable3 (talk) 19:08, 1 January 2010 (UTC)[reply]

^{Yesss. 87.81.230.195 (talk) 15:32, 30 December 2009 (UTC)}[reply]

You can't imagine fish having a use for mucus? The fish might disagree:[5] Even coral have mucus:[6][7] Here's an analysis of mucin evolution:[8]. Mucins are related to proteins with Von Willebrand domains. Gel-forming mucins are pre-vertebrate, and they're related to hemolectin in fruit flies: "The important characteristics of a gel-forming mucins can be traced down to deeply branching organisms such as Nematostella. This suggests not only that the gel-forming mucins are ancestors to hemolectin and VWF but also that gel-forming mucins have a long evolutionary history." Membrane-anchored mucins evolved in vertebrates. More in this PhD thesis. Fences&Windows 19:32, 2 January 2010 (UTC)[reply]

Ah, I think I misread that comment, you meant those glands in particular. Fences&Windows 19:38, 2 January 2010 (UTC)[reply]

the ether oxygen in morphine and related opiates seems ring-strained

Am I correct? I remember doing a problem set for a formyl ester of a pyridine-type 1-naphthol kinda heterocycle, and predicted nucleophilic catalysis where the pyridine nitrogen would attack the carbonyl carbon, facilitating hydrolysis. (General base catalysis was predicted too.) However they marked the first prediction wrong because they thought this pyridinium intermediate would be ring-strained (the alcohol oxygen would have to be bent a little out of the plane in order to form the intermediate). However, looking at the structure of morphine, it seems that such oxygen atoms would be even more strained and this compound exists (stably!) in nature! Now a) I am quite confused b) I wonder if this ether oxygen is part of the "reactive" part of the molecule, i.e. does it interact with the active site or get cleaved? It seems more stable than an epoxide but less stable than a THF ring. John Riemann Soong (talk) 19:44, 29 December 2009 (UTC)[reply]

The cyclic-ether in morphine is not ring-strained. Puckered 5-membered ring is a fairly stable conformation in general. Your description of your problem is too convoluted and non-specific (naphthol is not related to pyridine! What exact pyridinium intermediate structure did you have in mind?) Please get a drawing program so you can upload diagrams...a picture is worth a thousand technically-confused words. DMacks (talk) 16:48, 31 December 2009 (UTC)[reply]

inner ear and the nervous system

can an inner ear complication affect the nervous system ? —Preceding unsigned comment added by 24.82.182.93 (talk) 20:14, 29 December 2009 (UTC)[reply]

This is verging on a medical question. Remember we cannot answer medical questions. If any editor thinks I'm stretching this rule too far, please let me know. --220.101.28.25 (talk) 02:20, 30 December 2009 (UTC)[reply]

I dunno it sounds like a med school question too. I'm thinking lymph drainage... John Riemann Soong (talk) 03:51, 30 December 2009 (UTC)[reply]

Vestibulitis? I note that's a redlink. What I'm talking about is a condition causing vertigo and nausea, mostly caused by a virus.--TammyMoet (talk) 10:52, 30 December 2009 (UTC)[reply]

Labrynthitis is one. Eighth Nerve (the auditory nerve) damage is another. My 8th nerve is in bad shape, causing severe dizziness. Basket of Puppies 19:05, 30 December 2009 (UTC)[reply]

Cutaneous nerve endings

If cutaneous nerve endings exist in the outermost layers of skin (save for the epithelium), how does blubber and fat layers help animals that live in really cold regions (terrestrial + marine)? I was walking a bit today (in New Jersey) without my earmuffs and began to wonder how a wolf, for example, could possibly deal with walking in the snow without boots? DRosenbach ^{(Talk | Contribs)} 20:17, 29 December 2009 (UTC)[reply]

Countercurrent heat exchange. [9] -Nunh-huh 20:33, 29 December 2009 (UTC)[reply]

Nice link. But that's just how the limb, in my example, doesn't freeze off. How does it not hurt to have one's limb "just above the freezing temperature"? DRosenbach ^{(Talk | Contribs)} 21:52, 29 December 2009 (UTC)[reply]

I think your question assumes that there is a threshold temperature below which mammals consistently experience pain. Do you have a source for that? If not, I would posit that there is no such threshold. -- Scray (talk) 02:09, 30 December 2009 (UTC)[reply]

If that is the normal temperature, then it won't hurt. It would be pointless to have pain from a normal activity. Pain responses evolve to stop an animal doing something harmful. --Tango (talk) 02:12, 30 December 2009 (UTC)[reply]

Signal adaptation. There are many ways of silencing constant pain signals. We're not evolved for too much cold weather exposure, but note that pain adaptation to cold also happens to humans. John Riemann Soong (talk) 06:10, 30 December 2009 (UTC)[reply]

can't remember the name of a cognitive idea

the idea is that once you hear something (say my friend tells me about lindsay lohan), you will continue hearing about lindsay lohan, or lindsay lohan will be referenced more often by others. what is that called? —Preceding unsigned comment added by 68.150.211.52 (talk) 21:46, 29 December 2009 (UTC)[reply]

Priming (psychology)? --Mr.98 (talk) 22:05, 29 December 2009 (UTC)[reply]

Synchronicity? --Neptunerover (talk) 04:51, 30 December 2009 (UTC)[reply]

Rupert Sheldrake's idea of morphic resonance might be thought relevant. 87.81.230.195 (talk) 01:53, 31 December 2009 (UTC)[reply]

There may well be a question to which Sheldrake is the answer, but I'm pretty certain it is not any kind of science question. SpinningSpark 02:20, 31 December 2009 (UTC)[reply]

Why?--TammyMoet (talk) 15:28, 31 December 2009 (UTC)[reply]

Just to be clear, I didn't mean to imply that I myself endorse the concept, or I would have been more definite. 87.81.230.195 (talk) 16:54, 1 January 2010 (UTC)[reply]

Interconnectedness? ~A H 1^(TCU) 00:23, 1 January 2010 (UTC)[reply]

how to measure the basicity of lithium aluminum hydride? will it deprotonate RNH2?

I'm looking this article reduction of valine. It seems to me that well, lithium aluminum hydride will react with the zwitterion three times before it actually does a reduction, and then it has to reduce the resulting aldehyde again! That's like 5 equivalents of hydride! I guess 1.26 mmol of LiAlH4 is barely enough? With each further oxygen on the aluminum atom, doesn't it become less good of a hydride donor? Would there start to be trouble in reducing the carboxylate?

Is it more economical to deprotonate an amino acid before reaction? But how would I do it and then extract it into aprotic solvent? Is NH2-R-COO- more or less ether-soluble than NH3+-R-COO-? John Riemann Soong (talk) 22:10, 29 December 2009 (UTC)[reply]

How can change the color of mercury

How can change the color of mercury from the normal color to any color for example blue or black or red I ask to send the answer to the e-mail (redacted)I thank Hassan treated with I'm waiting for the answer as soon as —Preceding unsigned comment added by 91.144.37.8 (talk) 23:55, 29 December 2009 (UTC)[reply]

You wouldn't mean this kind of Mercury would you? If so, it's not real, it doesn't exist. Or maybe you are looking for a way of faking red mercury, also doesn't exist. SpinningSpark 01:22, 30 December 2009 (UTC)[reply]

If mercury is combined with oxygen, it makes Mercury(II) oxide which is a red powder. Heating mercury is extremely dangerous due to the likely inhalation. Mercury compounds listed at Category:Mercury compounds have various colors ranging from black, to white, to red, to yellow. I did not see any blue ones listed. Many are poisonous or even explosive. Edison (talk) 17:58, 30 December 2009 (UTC)[reply]

From the caption to Mercury in color: The color image...was generated by combining the mosaics taken through...filters that transmit light at wavelengths of 1000 nanometers (infrared), 700 nanometers (far red), and 430 nanometers (violet). These three images were placed in the red, green, and blue channels, respectively, to create the visualization... The human eye is sensitive only across the wavelength range from about 400 to 700 nanometers. Cuddlyable3 (talk) 18:11, 30 December 2009 (UTC)[reply]