Wikipedia:Reference desk/Archives/Science/2007 September 13

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[edit] September 13

[edit] The Body's Capacity & Ability To Die

Any input is appreciated. Thanks. Let's assume that we have an "average" person (whatever that means ... average age, height, weight, health condition, etc. etc. etc.) And this person wants to die (i.e., "passively" commit suicide). Let's assume that there is nothing at all wrong with his mental health ... that is, he is not suicidal / depresssed -- but, rather, that this is simply a medical experiment. Say that this person simply goes somewhere (let's just say, he goes and lays on his bed) and he simply stays there. Never, ever leaves the bed. (For illustration, we can add the fact that he is restrained / handcuffed / etc. -- although that is irrelevent, I think.) The location of the bed is essentially irrelevant -- but I want it to be a controlled environment (like his bedroom) -- as opposed to outside in the desert or a mountain or the ocean or his back yard or the highway or whatever (where contending with the elements and/or with intervention of other humans/animals is an issue). This person affirmatively does absolutely nothing -- does not eat, drink, medicate, etc. -- he just passively lays on the bed ... and (perhaps) his body naturally / passively excretes or sleeps or whatever a human body would passively do. About how long would it take for him to die? I assume that the cause of death would be lack of water / dehydration --- is that correct? (I have always heard that when you are lost or deserted or abandoned, the critical health worry is lack of water.) If so, what exactly would happen to his physical body that would cause the body to die? In other words ... no water enters his body ... and then what ... so what? What is the reaction of the body, at this point? Finally: if the person were unrestrained and free to move about (no handcuffs) ... would his physical body (and/or his mind) somehow "force" him to seek water/food/assistance/ at some point? In other words, does the body have some type of defense mechanism that will force the guy -- whether he wants to or not -- to extract his body from danger and seek survival (i.e., food, water). Restated, perhaps: which would "trump" the other ... his (mental?) willpower to die or his physical body's natural / reflex / defense mechanisms to survive? (if the latter even exists). Thank you. (Joseph A. Spadaro 02:32, 13 September 2007 (UTC))

Yes the restrained guy would die of thirst. But I would expect the thirst and hunger to overcome the will to die (if the person is in normal health and psycology). Graeme Bartlett 02:36, 13 September 2007 (UTC)
Exactly as with your previous question - you are asking a very contrived hypothetical fenced-around-with-caveats question. What makes you think that anyone would have ever studied such a thing? If they haven't (and it's pretty certain that no such study has been or ever (ethically) could be done) - then how on earth do you think anyone can come up with an actual answer? You're just going to get another bunch of complaints about the question and (possibly) random speculations! SteveBaker 03:23, 13 September 2007 (UTC)
Plenty of people have had access to food and water, and yet had the willpower to refuse them until death. See Hunger strike for examples. Typically humans can live for several weeks without food, and about three days without water. In favorable conditions, people have lived longer than two weeks with no water supply. The current documented record is 18 days.
If you stopped eating and drinking you would typically lose 2-3 liters of water per day. Once about 2% of your normal water volume has been lost, you would begin to experience thirst and discomfort, loss of appetite, dry skin and constipation, like a bad hangover. Then your heart rate would increase to compensate for decreased plasma volume and blood pressure, and your body temperature would rise because of decreased sweating. At around 5% to 6% water loss, would become sleepy, experience headaches and nausea. At 10% to 15% fluid loss, muscles become spastic, vision fails, and delirium may begin. Above 15% are you will not survive as you will begin to suffer multiple organ failure because your blood will be too viscous and you will have too high a concentration of salts in your plasma. Rockpocket 07:17, 13 September 2007 (UTC)
Isn't there a "Rule of 3" for human survival? All things being equal: three days without water. Three weeks without food. And three months living outside without shelter? --24.249.108.133 19:09, 13 September 2007 (UTC)
The three months one is obviously dodgy. What happens after three months that means you suddenly have to die? ΦΙΛ Κ 17:46, 17 September 2007 (UTC)
This is a practise that is currently under discussion in the Netherlands as an alternative to euthanasia (or stopping the administration of medication - quite the opposite). It's called versterven - that's a link to the Dutch article, which doesn't link to any other language Wikipedia and neither Wiktionary nor my dictionary gives a translation. It is generally used for old people for whom there is no point in living on. No food or drink is given to the patient, who (the article says) dies from dehydration after a few days (up to two weeks), as a result of vital organs failing one after the other. "It is a slow, but mild and peaceful way of dying provided the patient gets proper care, such as administration of pain killers and the wetting of the lips, which suppresses sensations of thirst. Refusal to take food or water is a natural phenomenon in late stages of dementia and several other diseases. [...] Experts estimate that in the Netherlands, in 4 to 10 % of mortalities, 'versterving' has taken place." So it's quite common. Exceedingly common even. In the Netherlands, at least. Does anyone know the English word for this so I can put this translation in an English article? DirkvdM 09:29, 14 September 2007 (UTC)

[edit] Murder Victim's Multiple Stab Wounds

When reading news accounts of a crime, I often see things like this: "the medical examiner states that the victim was stabbed 128 times" (or some such). How in the world do they calculate that number? I don't understand. Not to be crude -- but -- when a body has been stabbed umpteen gazillion times, what in the world can you distinguish? Isn't it all just one big "glob" of a mess that would be impossible to sort out? Yet, they always seem to have the exact, precise number -- how is that? Any insight is appreciated. Thanks. (Joseph A. Spadaro 03:16, 13 September 2007 (UTC))

Once the body is cleaned, assuming it hasn't been completely mutilated, it wouldn't be that hard to make out individual wounds. Someguy1221 03:34, 13 September 2007 (UTC)
Besides, I don't think I ever heard of a number as big as 128 - it's usually less than 20 and even then you tend to hear things like "at least XX" - meaning that they counted XX holes but they aren't sure whether some of the holes represent multiple stabbings. SteveBaker 03:37, 13 September 2007 (UTC)
If someone is stabbed xx number of times, chances are it was done in a maniacal fashion. I can't see an enraged killer stabbing someone xx times precisely in the same location with the same angle and force. Check out old coroner photos. Crime scenes are pretty gruesome, but once the body is washed, it's pretty obvious where each would is. --24.249.108.133 19:14, 13 September 2007 (UTC)
And it's not too hard to tell where the knife has gone in pretty much near the same area. There is a whole grim science of this sort of thing. --24.147.86.187 12:26, 14 September 2007 (UTC)

[edit] Imported energy

what is The share of energy resources used by the United States that comes from other countries? —Preceding unsigned comment added by 71.98.105.119 (talk) 03:35, 13 September 2007 (UTC)

This was asked just a few days ago. The US consumes 20 million barrels of oil per day and produces only 8 million. Therefore about 60% of oil is imported. It's likely that natural gas and other resources are imported too - but I don't have figures for that. SteveBaker 11:49, 13 September 2007 (UTC)
That's just oil, not other energy sources. Also, you are talking about the net result. The US could export some oil and import other energy sources, which leads to the question what precisely the questioneer wants to know. DirkvdM 09:37, 14 September 2007 (UTC)
The US is a net importer of natural gas (3.6 billion cubic ft imported of 21.9 bcf consumed), is just barely a net exporter of coal (1.105 million short tons produced, 1.102 million short tons consumed), and produces a bit more electricity than is consumed (3.9 billion kilowatt hrs generated, 3.7 consumed - but recall that most electricity is generated by burning coal). I do not have the gross energy balance, but it is certain that with the overwhelming contribution of oil imports that the net is pretty close to the value for oil. Cheers Geologyguy 04:30, 16 September 2007 (UTC)

[edit] pneumonia vaccine

This question has been removed. Per the reference desk guidelines, the reference desk is not an appropriate place to request medical, legal or other professional advice, including any kind of medical diagnosis, prognosis, or treatment recommendations. For such advice, please see a qualified professional.
This question has been removed. Per the reference desk guidelines, the reference desk is not an appropriate place to request medical, legal or other professional advice, including any kind of medical diagnosis or prognosis, or treatment recommendations. For such advice, please see a qualified professional. --~~~~

Statistical information and not advice was requested by this question which makes the removal of this question highly suspicious as to the true purpose and intent of the science reference desk. I am very disappointed with the Wikipedia science reference desk for being unwilling to provide reference to statistical data for various medications such as side effects and/or number of deaths or other complications. In fact I have lost all confidence now as to the Wikipedia having any authoritative information to give versus pure speculation. Clem 15:04, 13 September 2007 (UTC)

Responded on Clem's talk page. TenOfAllTrades(talk) 20:57, 13 September 2007 (UTC)

The responses to the original question serve as a perfect example of how otherwise intelligent and knowledgeable persons can fall victim to mind set. The intent of the original question was no more than to determine why prolonged muscle soreness is a side effect of an pneumonia vaccine. Instead of a straight answer however what we find here is a dance based not on providing a simple reference or answer but a dance based on a mind set inappropriately applied for no other reason than to show off ones talent to do the dance. Clem 10:17, 14 September 2007 (UTC)

This is not the place for that debate - please take it to the Discuss section or to private talk pages. SteveBaker 14:34, 14 September 2007 (UTC)

[edit] Molar Mass of a Specific Substance

What is the molar mass of a substance for which each molecule contains 9 carbon atoms, 13 hydrogen atoms and 2.33*10^-23g of a complex ion? It is a challenge question that was asked at school, and I don't know how the complex ion part fits in.- 210.49.128.130 06:56, 13 September 2007 (UTC)

Well, I was going to say just do it like a normal problem. The molecules consists of carbon, hydrogen, and a complex ion, and between that mass and the periodic table you know the individual masses of these constituents. However, that figure for the mass of the complex ion seems awfully low. Someguy1221 07:14, 13 September 2007 (UTC)
Well, it doesn't matter what the complex ion actually is in this case, and it does work out to a near-integer molar mass. (I agree that it's a not a particularly complex complex—the complex ion in this case is something more like hydroxide or methylene than one of the big six-liganded cobalts at complex (chemistry).) You're given the complex ion's contribution to the mass in grams per molecule, and you need to convert that into grams per mole. How would you do such a conversion? TenOfAllTrades(talk) 12:47, 13 September 2007 (UTC)
By multiplying the mass of the complex ion by Avagadro's number? - 210.49.128.130 14:03, 13 September 2007 (UTC)

[edit] Strength of chicken egg shells

I need to know at what pressure a standard chiken's egg shell will begin to crack and eventually break. I have researched through certain encyclopeadias and some wikipedia articles but haven't been able to find a definite answer 41.241.236.5 10:11, 13 September 2007 (UTC)

This would not be a constant and would vary from egg to egg, from chicken to chicken, even breed of chicken to breed of chicken. Factors such as the chickens diet can affect the strength of the shell - low protein or vitamin D can cause thinner shells [1] . A small, invisible to the eye, facture or imperfection in the surface of the shell could render it very fragile. Lanfear's Bane 10:58, 13 September 2007 (UTC)
They are also a lot stronger when compressed end-to-end than from side-to-side. SteveBaker 11:28, 13 September 2007 (UTC)
Is there any truth to the story that the even the current World's Strongest Man would be unable to crush an egg by compressing it end-to-end? It's certainly an oft-repeated 'fact'. --Kurt Shaped Box 15:28, 13 September 2007 (UTC)
I strongly suspect that's a joke/trick to get people to try it - they brace themselves and apply a lot of force - the egg crushes really, really easily (duh!) and kersplat...you have egg on your face! SteveBaker 20:56, 13 September 2007 (UTC)
I shouldn't be surprised that this has been studied in depth here -- kainaw™ 15:38, 13 September 2007 (UTC)
It's actually supposed to be impossible for a human to crush an egg by squeezing. For the einstein year of physics, the IOP released a booklet of 20 physics "tricks" and this was one of them. I have a copy in front of me. "Challenge the audience to break the egg just by squeezing it, wrapping the egg in a plastic bag if they wish, believe it or not it can't be done!". They make sure to explain that hair-line cracks could make the egg break easily, and that any rings could apply uneven force which would break it. Yes it sounds a bit rubbish for a physics demonstration, but these "tricks" were designed to be done with very common materials. Capuchin 07:24, 14 September 2007 (UTC)
The document is avaliable here. The egg thing is on page 23 and there are videos of all the demonstrations in the document here. I find the video of the guy (lady?) trying to break the egg hilarious :) It's hard to shake the notion that it should be easy to break. There's lots of good stuff in there. Capuchin 07:28, 14 September 2007 (UTC)
WP:OR -- If you apply EVEN pressure, eggs really are difficult to break. The problem is that when they DO finally break, they do so while you're applying a lot of pressure to them. That's how I painted my parents' ceiling with egg. --Mdwyer 23:00, 14 September 2007 (UTC)

[edit] mms thru orkut!

Is there any chance of sending a song from "Youtube" to mobile...? or is there any other site which will enable us to send MMS thru computers to mobiles? Temuzion 10:33, 13 September 2007 (UTC)

Msn messenger enables you to send text messages to mobile phones, that might be a start? SGGH speak! 10:38, 13 September 2007 (UTC)
I already know the sites through which I can send dry text messages for free, unlimited time...I need some websites of not text mesages...but which will enable us to send multimedia messages..! Temuzion 09:05, 14 September 2007 (UTC)

[edit] Weird bug

I was wondering if someone could help in identifying this insect. I live in hyderabad, INDIA. Does it bite humans ? Here is a snap I took, I am sorry I do not know how to embed the snap here. Thanks to all of you. [2] Vijeth 12:09, 13 September 2007 (UTC)

It's a grasshopper, and I don't think it bites. But I have no idea of the species. Graeme Bartlett 12:17, 13 September 2007 (UTC)

Thank you Graeme, It does look very scary though. I find the colors very intriguing. Vijeth 12:27, 13 September 2007 (UTC)

It is an amazing looking creature. Do you want to upload it to wikipedia? You click on the uploadfile on the left, select a copyright and point it to your file, and give it a name and description. Hopefully someone knows more exactly what it is. Graeme Bartlett 12:33, 13 September 2007 (UTC)

Yes, I did upload the file, and yet I do not know how to embed it here. I think I named it ColorfulGrasshoper.jpg Vijeth 12:54, 13 September 2007 (UTC)

You can embed it using [[Image:ColorfulGrasshopper.JPG]] - or to display it at a more reasonable image size, and with a title, you could say [[Image:ColorfulGrasshopper.JPG|250px|thumb|A colourful Grasshopper]]. SteveBaker 13:10, 13 September 2007 (UTC)

Thank You all. Now I am wiser. Vijeth 14:34, 13 September 2007 (UTC)

I think it is Poekilocerus pictus. They won't bite you but you should under no circumstances eat it — they eat milkweed and are thus poisonous (which is probably what all those colors are trying to convey). --24.147.86.187 20:38, 13 September 2007 (UTC)
These are very common where I live but instead of milkweed sit down to a table of Philodendron. Clem 01:56, 14 September 2007 (UTC)

I went out to check, and its still there on the same branch as yesterday. Is it dead ? And yes I don't think I plan on eating one too soon. :) 202.53.8.234 09:33, 14 September 2007 (UTC)

Steve, shouldn't you remove this question? Isn't 'does it bite' a health-related question? What if it's seriously poisonous? Or am I not allowed to say that because it might unnecessarily scare the questioneer, as TenOfAllTrades recently told me? DirkvdM 10:01, 14 September 2007 (UTC)
Discussing the color of it's skin may be a health question but could be race related which definitely qualifies it for speedy removal. Clem 10:27, 14 September 2007 (UTC)

[edit] Breaking locks

Ok, this is a serious question and I'm not a criminal so don't go calling the police of anything lol
I've lost the key to my bicycle lock and now the bikes stuck at college. Short of getting bolt cutters or a chainsaw, how can I cut or break the lock? Its a D-lock (like a large horseshoe). My mate told me that if you put lighter fule in the lock and light it that it will unlock. Is this true? Any help, thanx! Hyper Girl 13:21, 13 September 2007 (UTC)

Incidently, lighter fuel as in naptha wouldn't do much. But liquid butane, on the other hand, would. You'll find it in the janitor's closet as 'gum remover', or in electronics stores as 'freeze spray'. As the liquid boils away, it freezes the lock enough to cause it to become brittle. One it is brittle, it can be broken with a hammer or a prybar. That's the theory, anyway. In practice, you'd be better trying some of the other suggestions, here. Most of them are less flammable. --Mdwyer 22:57, 14 September 2007 (UTC)
Liquid nitrogen will work better, isn't flammable, and is probably available on better college campuses everywhere.
Atlant 15:01, 17 September 2007 (UTC)
Common sense says that something as simple as that is very unlikely to work, otherwise bike thieves would be doing it all the time and no-one would spend money on such an insecure type of bike lock ! I suggest you find a locksmith's shop or hardware store and ask their advice. And next time get a spare key cut and keep it somewhere safe. Gandalf61 14:02, 13 September 2007 (UTC)
It's a popular Internet fact that certain models of "Kryptonite" brand locks can be opened in seconds with a ball-point pen. (Search YouTube for this.) Otherwise, if you don't know how to use a lock-pick, I'd just suggest just taking a hack-saw to it. (If you still have any paperwork proving you own the bike, I recommend putting that in your pocket, it would make things easier if a cop notices you.)APL —Preceding unsigned comment added by APL (talk • contribs) 14:23, 13 September 2007 (UTC)
Also, do *not* use a chainsaw for this. You will hurt the saw, and most likely yourself as well. An angle grinder would be more appropriate, but that too can be a harsh mistress, so wear proper safety gear. --Sean 15:05, 13 September 2007 (UTC)
Know anyone with an Oxyacetylene torch? Those D-locks can be tough. Take all appropriate safety precautions, of course. --Kurt Shaped Box 15:23, 13 September 2007 (UTC)
I found that it was much easier to drill right into the key-hole (well, it is actually a circle) of the D-Lock. It is the weakest point. With a 1/2" drill bit, it takes about 5 minutes to remove the lock and it falls apart. This is not useful for thieves because it makes a hell of a lot of noise. -- kainaw™ 15:32, 13 September 2007 (UTC)
One word: thermite. Lanfear's Bane 15:34, 13 September 2007 (UTC)
A jack can also be used to break a U-lock as well. Donald Hosek 16:34, 13 September 2007 (UTC)
Some locksmiths might have tools that can pick your lock. If not, an angle grinder will probably do it; but takes a while. --192.58.221.248 18:40, 13 September 2007 (UTC)
You could also get/borrow a sledge hammer and knock it out of its housing with that. Aim for the "lip" of the straight part of the lock, swinging away from the U part of it. --24.147.86.187 —Preceding unsigned comment added by 24.147.86.187 (talk) 20:16, 13 September 2007 (UTC)
The problem is that the single defining feature of one of those things is that you shouldn't be able to get them off without the key! The good ones are made of case-hardened steel - which will take a very long time and a lot of hacksaw blades to get off. Drilling out the lock is probably the least tough way in - a hand-held drill with a range of bits would get you through it. I think we can discount the lighter fluid thing - that's exactly the kind of urban legend that's NOT going to work. You could probably get it off with a lock-pick - they are illegal in the USA - but easy to find on the Internet - and they are really alarmingly easy to use! (I'm not telling you how I know this!) You can also employ a locksmith to get it off - they are skilled and licensed to use those kinds of tools. As a lateral-thinking kind of a question - what is the D-lock wrapped around on the bike? You can saw through a wheel fairly easily if it's not also wrapped around the frame - most bike wheels are pretty cheap to replace. A photo of the locked up bike might reveal some cunning topological things that could help. SteveBaker 20:52, 13 September 2007 (UTC)
Go up to a campus cop or building custodian, smile your sweetest HyperGirl smile, show him some proof it is your bike, and ask if he could please help you out by using his bolt cutter. It will take about 2 seconds to cut the lock off. Or go to the hardware store and buy a hacksaw and an extra metal cutting blade, then spend 5 minutes or so cutting through the lock. Either is far, far cheaper than hiring a locksmith. If you go to a locksmith with the brand of padlock and the number on the bottom, he should be able to make a duplicate key for a small price. Edison 17:29, 14 September 2007 (UTC)
If it's a reasonably good bike lock, made with 3/4" case-hardened steel, you'll be hacking away with that hacksaw for hours and getting through an awful lot of blades. Bolt cutters won't touch it either (and if you try, you'll damage them). If you intend to brute-force your way in, then drilling out the lock (which won't be made of really tough materials) is the way to go. Look here [3] some of the bike locks succumbed to a hacksaw - but in one case, the reviewer said "Sawing on the 16 mm shackle for five minutes only got me about 3 mm deep." in another "Unlike less hefty locks, the hacksaw and the bolt cutters barely ruined the finish on the chain. However, I did wound the Beast with the hammer. My battering dented the padlock and made it impossible to open without a screwdriver."...not all bike locks are that sturdy - but in some cases, hacksaws and bolt cutters won't help. SteveBaker 17:46, 14 September 2007 (UTC)
The questioner did not specify what make or model of lock it was, so it may not be the sturdiest $90 5 pound lock. A 5 pound lock adds substantially to the mass of a bike whose designers made it lightweight, and some lock purchasers do not choose the heaviest lock. Lesser locks were opened easily by the writer of the Slate article, and with respect to hacksawing 3 mm into a 16mm shackle, the writer estimated he could have finished sawing through it in 35 minutes. I would suggest that on a campus, via the social engineering practice described by Mark Twain with respect to white-washing a fence [4], it would be possible to get passersby to volunteer their efforts. Several hacksaw blades would be cheaper than a locksmith. Edison 18:04, 14 September 2007 (UTC)
That's assuming a homogenous material. I was involved in testing some jailbars once, and one of the tests was to see how vulnerable to cutting they were. The first hacksaw blade cut a notch 2mm deep in the bar before hitting the hardened core; the next 49 blades all wore out without making the cut measurably deeper. --Carnildo 20:40, 14 September 2007 (UTC)
Did you ever try the classic 'file of the type that may be hidden in a cake', as a matter of interest? --Kurt Shaped Box 17:14, 15 September 2007 (UTC)
Ironically I just had to cut the cable of my bike a few days ago because I also lost the key. It was one of those plastic coated varieties with lots of strands of wire weaved together. It was disturbingly easy. I stripped away the plastic and then (with a friend) held the chain taut. Then I started cutting and within say 20 seconds I was more or less through. Bolt cutters would I presume also easily do the job. A D lock would be much harder but it will obviously depend greatly on the type. You could try with a hacksaw first and if you don't get anywhere, reasses your options. Bicycle lock means some. Alternatively you could try asking your campus security or perhaps at a bike shop or a locksmith as others have suggested. Obviously once you've found out how easy it is to actually break your lock depending on how risky the areas you store your bike and how valuable it is to you, you might want to consider a better lock in the future, just don't lose the key (make sure you have a spare!). BTW, you might want to tell campus security (or someone similar) about this before you start, it's likely to be the best way to avoid any problems if someone thinks you're trying to steal the bike. They'll likely ask for some proof it's your bike and if you don't have any they'll likely record your details so make sure you have your student ID, driver's license (if any or other forms of ID) and stuff with you Nil Einne 19:52, 18 September 2007 (UTC)

[edit] sex

what should be a healthy penis dimension —Preceding unsigned comment added by 203.115.85.243 (talk) 14:00, 13 September 2007 (UTC)

See penis. -- Flyguy649 talk contribs 14:00, 13 September 2007 (UTC)
Also micropenis for a quick ego boost. --Sean 15:07, 13 September 2007 (UTC)
And human penis size Laïka 20:24, 13 September 2007 (UTC)
The health of the penis and its size are two completely unrelated subjects. Unless you have elephantitis. --24.249.108.133 19:18, 13 September 2007 (UTC)
Humor in bad taste, man, humor in bad taste... :) bibliomaniac15 15 years of trouble and general madness 02:21, 14 September 2007 (UTC)
Zero if you're female Nil Einne 19:32, 18 September 2007 (UTC)

[edit] Corpus Cawhatum?

I was watching a TV science-fiction show the other day and one of the key plot points was that left-handed people were able to process a particular chemical better as the corpus callosum is larger in those of a sinister nature. Technobabble aside, is it true that that particular part of the brain is larger in lefties than righties? GeeJo (t)⁄(c) • 17:04, 13 September 2007 (UTC)

According to this paper in the journal Psychobiology, "Left-handers possess slightly larger CCs than do right-handers...". I think I'll add that to the article. —Keenan Pepper 20:20, 13 September 2007 (UTC)
The theory is that most right handers are very solidly right handed - but left handers tend to be more balanced in their abilities between left and right. One easy demonstration of this is that most left-handed people can write better with their right hand than right-handed people can with their left hand. Since these abilities have to do with the left and right sides of the brain, it's not unlikely to suppose that a left-hander has/needs better communication between the two sides than a right-hander does. The corpus callosum is the structure that connects the two sides of the brain and contains all of the 'wiring' that goes between them. Whether having a bigger corpus callosum tends to make you turn out to be left-handed - or whether being left-handed from an early age causes the corpus callosum to grow larger to cope with the increased demand is unclear. But the end result is that the difference is there. SteveBaker 22:40, 13 September 2007 (UTC)
Yes, a point to keep in mind is that lefties go through life in a world that's backward to them. It's important for them to be able to use their right hand at least to some degree, whereas there's less incentive for a righty to learn to use his/her left hand. I'm at work, so I can't check the site Keenan posted, but I'd bet the authors were careful to point out the direction the causation went, or if that's even been determined. Matt Deres 18:44, 14 September 2007 (UTC)

[edit] Two questions

I have 2 questions. Would a sudden nuclear splitting of any thing (for instance, of an apple or even a man) lead to the nuclear explosion? Where can I find the chemical formulas of common food item (bread, beaf etc.)? —Preceding unsigned comment added by 85.132.14.38 (talk) 19:43, 13 September 2007 (UTC)

Regarding your second questions, beef or bread won't have a chemical formula, as they're not uniform chemical compounds as such; they're made of varying amounts of water, proteins, fats, vitamins, and other compounds that do have chemical formulas. You might google "beef chemical composition" to get a rough idea, from which you could say that it's, for example, 70% H2O, 12% NaCl, and so on. jeffjon 19:51, 13 September 2007 (UTC)
By "nuclear splitting" I assume you mean nuclear fission? If so, then no, things apples and human bodies cannot undergo nuclear fission and release energy. Organic matter is mostly made of light elements like hydrogen, carbon, nitrogen, and oxygen. Except for hydrogen, these nuclei can be split, but the process absorbs energy rather than releasing it. The reason is that for light nuclei, the nuclear binding energy increases with increasing mass. Only heavy nuclei like uranium and plutonium can release energy through fission. Image:Binding energy curve - common isotopes.svg may be enlightening.
At this point you might ask, why don't light nuclei undergo nuclear fusion and release energy that way? It's because the nuclei are all positively charged, so they repel each other strongly whenever they approach, and they cannot get close enough to fuse together. If you subjected an apple or a person to the temperature and pressure at the center of the Sun, the hydrogen in them would fuse into helium and release energy. You would need even higher temperatures in order for the carbon and oxygen to fuse. —Keenan Pepper 20:13, 13 September 2007 (UTC)
There are some common food items that are pure chemicals - water (H2O), salt (NaCl), sugar (C12H22O11), alcohol ((C2H6O)...but most things are vastly more complex mixtures. Things made from plant and animal tissue (bread, meat, peas, potatoes, etc) will contain (for example) DNA which is a horrendously complicated compound whose formula would comfortably fill a telephone book. So there is really no chance of getting the formula for something like that. SteveBaker 21:57, 13 September 2007 (UTC)
Agreed. Just take a look at Titin:
(Click "show" to see the ridiculously long chemical name)

!!!! —Preceding unsigned comment added by Kurt Shaped Box (talk • contribs) 22:15, 13 September 2007 (UTC)

I've formatted with a rollup box so we don't have to see that horrible chemical name (also it messes up the horizontal scroll). Nimur 22:20, 13 September 2007 (UTC)

Yeah - but that's only the name - the formula is MUCH bigger! SteveBaker 22:29, 13 September 2007 (UTC)
Got it handy? ;) --Kurt Shaped Box 22:31, 13 September 2007 (UTC)
Y'know, I think this explains a little mystery -- I was wondering why this RD was 328K after the archiver ran tonight, instead of the usual ~100K. —Steve Summit (talk) 04:52, 14 September 2007 (UTC)
I'm not quite sure what you mean by "nuclear splitting" - but lets give that a shot. Atoms contain protons and neutrons (and other stuff). Most atoms in food have a few dozen protons and neutrons (at most). But atoms with LOTS of protons and neutrons (like maybe 100 of them or more) tend to be a bit unstable - they'll be sitting there and suddenly (for no obvious reason) kick out a neutron or a proton and in the process, they turn into something else.
For example, Polonium-210 atoms (the stuff that Russian guy in England was poisoned with) will sit around for weeks or months and then suddenly (and for no obvious reason), they'll turn into common-or-garden lead...atom by atom over the course of years, your lump of lethally dangerous polonium will change into boring old harmless lead. The protons and neutrons that these substances kick out are the radioactivity that you pick up with a gieger counter or whatever. But the atoms that make up almost all day-to-day objects (carbon, oxygen, hydrogen) are utterly stable - they aren't big enough to be unstable - so an apple (which contains sugar, water, starches and proteins - all made up mostly of carbon, hydrogen and oxygen) isn't radioactive at all - it's atoms stay just the way they are (although they'll eventually rearrange themselves from nice, tasty apple molecules into nasty smelly rotten fruit molecules...but all of the ATOMS are pretty much still the same). So no radiation.
But even a lump of weapons-grade uranium the size of an apple isn't going to explode in any particularly exciting way. It'll sit there emitting radiation as its atoms s-l-o-w-l-y turn from uranium to something else to something else...until it turns into something stable and stops being radioactive anymore. Some materials (like Polonium 210) do this fairly quickly (a matter of months to years) - others take thousands of years to decay. Now - here's the sneaky part. Some of these unstable atoms can be persuaded to kick out not one - but a couple of neutrons if you whack them hard with another neutron. So one atom could decay naturally - and the neutron it kicks out could hit another atom, causing it to kick out more neutrons (rather than waiting a few thousand years to do it 'naturally'). In a small quantity of (say) uranium, (like a chunk the size of an apple pip) that event is rather unlikely. The odds of one neutron hitting another atom are pretty small. But if you take a LARGE chunk of the stuff - then the odds get better because there are just so many more atoms it could hit. A chunk the size of an apple would be warm to the touch because of the heating caused by all that radiation. But at some point - if the lump is big enough ("critical mass"), nearly all of the neutrons that are emitted hit other atoms which kick out more neutrons that are ALSO likely to hit more atoms and make yet MORE neutrons. Before you know it, every atom in the entire lump of material is chucking out tons of radiation...KERPOW! (to put it mildly) - you have an atom bomb.
But this can't happen to an apple because it has super-stable atoms. Even if you put a chunk of radioactive uranium right next to the apple - the atoms in the apple are just too boring and stable - so neutrons come in from the uranium - hit the atoms in the apple and nothing much happens. So no KERPOW! So, to cut to the chase, an apple isn't going to explode no matter what you bombard it with.
SteveBaker 22:26, 13 September 2007 (UTC)

[edit] If you're a space artist ...

Let's say you're an artist on a spacecraft heading to Mars. Strangely, you are not required to perform any science experiment because they are taken care by robots. You're on the trip simply because we need to provide museums with top class original artworks (e.g.: pictures of nude Martians). What can you do to fulfill your job while you are in space?

  • Oil painting: Pigments stick well to the palette and canvas. Oil does not float. But the solvants may kill you and your pilot. Canvas may be heavy for a space trip.
  • Water color: I guess water and zero gravity may cause much trouble.
  • Pencil, crayon, pastel sketch: You need to fix yourself and the paper to the wall otherwise you may simply push yourself away from the paper.
  • Fountain pens, ballpoint pens, technical pens: Generally, these ink-based tools require gravity.
  • Taking photos: This shall be a piece of cake.
  • Carving: In addition to weight limitations, you may need sophisticated tools to help you keep the material from moving. On the other hand, dusts may damage your space craft.
  • Airbrush painting: Microscopic particles may be harmful to your health and also the spaceship.
  • Sandpainting: No gravity; no fun.

What else can you do? -- Toytoy 21:06, 13 September 2007 (UTC)

Probably none of the above because you'd run out of materials - mass being at a premium - and (as you say) little bits of 'stuff' floating around isn't recommended in zero g. I think your best bet is Photoshop. You can paint on a computer screen in zero g - you can send your pictures off for other people to look at, comment on, publish, by radio - and the entire gizmo is powered by the solar panels. One decent terabyte hard drive can hold more pictures than you could paint in a lifetime. Of course you might not literally want photoshop - there are lots and lots of other art programs - I'd take along a copy of Maya for 3D sculptural work. Or you could do it on the cheap with GIMP and Blender. You could take along a digitizing tablet with a pressure sensitive stylus for a more hand-painted feel. Incidentally, pencils and 'pump-action' ballpoints work OK in zero g (Remember that business of NASA spending a fortune developing a zero-g pen, then when they finally linked up with the Russians in the Apollo/Soyuz mission, the Russians were using pencils -- I sure hope that's an urban legend!) People anchor themselves to convenient surfaces with loops that they can tuck their feet into. Velcro is everywhere! I don't think sketching with pencils, crayons, felt-tips or ballpoints would be technically difficult - but lugging lots of spares and tons of paper might not be too great. Taking photos is indeed a piece of cake - but in the large inky voids between Earth and Mars in a teeny-tiny spaceship with just a couple of colleagues for subjects - your photos will definitely start to look a tad repetitive after the first few dozen! "This is Joe at the front of the space ship. This is Joe at the back of the space ship. This is Joe upside down at the back of the space ship...no - that's not Joe upside down at the front of the space ship - you just have the photo the wrong way up." ...yeah - that's going to get old fast! SteveBaker 21:48, 13 September 2007 (UTC)
The pressurized ball-point pen is an urban legend with a bit of truth in it. The pen was developed by an independant company using private funding, and was offered to NASA as a promotional gimmick to help them sell to their real market: the Air Force. In addition to working in weightlessness, a pressurized pen doesn't leak at high altitudes, and can write at any angle -- useful at 50,000 feet when the only available writing surface is the underside of your fighter's cockpit canopy.
And no, the Soviet Union didn't use graphite pencils: graphite flaking off is a major short-circuit hazard. They used grease pencils. --Carnildo 22:11, 13 September 2007 (UTC)
Snopes said both sides used both. --YbborTalk 22:14, 13 September 2007 (UTC)
Not only that but ball point pens do work in space to a degree evidentally, see Space Pen Nil Einne 19:30, 18 September 2007 (UTC)
Spider Robinson's Stardance trilogy is based on a dancer who explored free-fall dance. Why worry about existing art forms in space? In general, new technology both requires and enables new art forms. If you are absolutely stuck on static visual art, use the GIMP or Blender. -Arch dude 15:55, 15 September 2007 (UTC)
Let the temperature down, then try delicate ice sculpture, welding sticks of ice together with your breath through a straw.211.28.144.253 22:58, 16 September 2007 (UTC)

[edit] Pain

Totally hypothetical question here: from a medical perspective, which is likely to be worse: something hurting when it shouldn't, or something not hurting when it should? --67.185.172.158 21:53, 13 September 2007 (UTC)

Both are bad, and the degree of harm associated with each depends on the severity and extent of the condition. It's worth bearing in mind that loss of (or inappropriate excess) sensation of pain isn't a black and white matter. Depending on the patient, loss of sensation may be partial or complete, affecting small areas or the entire body. Inappropriate pain may be mild soreness or excruiciating burning. You really don't want to have the worst cases of either.
Pain has a number of benefits for the normal individual; see Pain#Survival benefit for some details. People without the ability to feel pain are susceptible to a great number of maladies, see Congenital insensitivity to pain, Congenital insensitivity to pain with anhidrosis.
Nerve disorders causing inappropriate pain, meanwhile, can lead to serious physical and psychological harm. (See neuralgia, phantom pain, chronic pain.) Trigeminal neuralgia is often excruciatingly painful, and has gained the grim moniker 'the suicide disease' in some circles. TenOfAllTrades(talk) 22:12, 13 September 2007 (UTC)
Ah, there's the solution to safely asking medical questions here - just say it's hypothetical. :) DirkvdM 18:37, 14 September 2007 (UTC)
Just my opinion, but lack of pain when there should be some would seem to lead to disaster. After all, the first primitive neural systems were/are just a sensor at each end hooked up to a muscle at the other end, so that when you get bitten on one side you move away. If that seems to be the basic underpinnings of the nervous system, I'd think that eliminating it would eliminate a major advantage the nervous system conveys. Similarly, the fact that evolution has allowed a great many disorders which allow there to be pain when there's nothing you can do about it, and substantially fewer disorders where there is no pain and there should be, would suggest their relative importances. Gzuckier 15:50, 17 September 2007 (UTC)
This doesn't answer your question but I heard of a case where a paralysed person put a hot pan on their lap while cooking. However tha pan was rather hot and this person ended up with some nasty burns on their legs because they didn't realise this. (Of course this isn't just the loss of pain but the loss of heat sensation as well). People who are paralysed have to learn many things, one of them is how to live with the loss of sensation including pain Nil Einne 19:27, 18 September 2007 (UTC)
Just FYI, pain and temperature are carried by the same pathways to the brain, so if you lose pain sensation, you lose temperature as well. --David Iberri (talk) 17:20, 19 September 2007 (UTC)

[edit] Tomato and Plastic.

Why is it that microwaving anything with tomato in it in a plastic gladware/tupperware/whateverware container makes the plastic go red in such a fundamental way that you can't ever clean it off? Nothing else I cook in them ever does that and the stuff washes off other kinds of containers just fine. Is there some magic formula of common cleaning substances that'll get rid of it? SteveBaker 22:55, 13 September 2007 (UTC)

I can confirm this Steve! The red colour in tomato is Lycopene, a terpene that is oil or fat soluable, and is more likely to dissolve in a hydrophobic plastic surface. Also heating above 100 degrees, which can happen in non water phases has a destructive effect on the plastic. Graeme Bartlett 23:41, 13 September 2007 (UTC)
Is it the same stuff that removes the skunk smell? or is a bath of tomato juice just a myth? :) Capuchin 07:36, 14 September 2007 (UTC)
It's not 100% myth, but it is not a very effective way of actually removing skunk smell. It is an OK way of "masking" it. Though frankly if you have been skunked, masking it is a pretty good alternative if nothing else is available! Note though that if you have actually been skunked your nose will in the short term lose a great deal of sensitivity and you won't even realize how bad you smell (I know from experience!). --24.147.86.187 12:23, 14 September 2007 (UTC)
Wow! Thanks Graeme - that's a superb answer! So basically, if I microwave my left-over spaghetti/meatballs in a plastic container, I'm screwed. The colour has DISSOLVED into the plastic (now that's an odd thing!) and is therefore immune to being washed off or bleached out. Wow! Oh well, I guess I'll have to reserve the red-tinted containers for tomato products only. I presume that the Lycopene that's dissolved into the plastic isn't doing my food any harm - I mean, it's not harboring bacteria or anything because it's safely locked inside the plastic - right? There should be a market for pre-tinted red tupperware that doesn't show the dissolve lycopene! Many thanks! SteveBaker 13:35, 14 September 2007 (UTC)
I have found a simple and cost-effective way of avoiding this problem. I don't eat anything with tomatoes in! DuncanHill 13:38, 14 September 2007 (UTC)
There is a product available in the US that is supposed to deal with these stains. It is used in a dishwasher. I haven't used it myself and don't want to add any commercial links, but perhaps Googling for "plastic booster" might lead one in the right direction. --LarryMac | Talk 18:29, 14 September 2007 (UTC)
Active ingredient appears to be Benzoyl Peroxide...sounds like it's a bleach which is also used in the manufacture of thermoset plastics...I guess that makes sense, it could also dissolve in the plastic and bleach out the colour and since it breaks down rapidly with heat, it's going to disappear quickly when you next use the container. Neato! I'll see if I can get some. Thanks! SteveBaker 20:32, 14 September 2007 (UTC)
My ex was a fount of knowledge regarding anything in the kitchen and she used to spray chopping boards with a nonstick cooking spray when preparing tomato dishes. I think she did the same for chilli and red peppers, maybe they contain lycopene as well. I googled here[5] and found a few pointers which seemed to indicate that this might work even when you microwave a dish. Regarding your link to benzoyl peroxide I guess you noticed it's highly carcinogenic? Personally I'd avoid it and try using glass or porcelain for heating up tomato dishes in the microwave as they won't stain so you can use everyday detergents for cleaning. --Cosmic joker 00:44, 15 September 2007 (UTC)
I actually did a little web search on the lycopene content of red bell peppers (one of my favorite foods!) a while back. It seems they have a little bit, but not really very much (much less than tomatoes anyway). The red color is probably cryptoxanthine. I was disappointed at the time. However the latest study on lycopene suggests it may not be quite the magic bullet that had been hoped. --Trovatore 23:09, 17 September 2007 (UTC)
As our article on the stuff says, it's not carcinogenic when diluted (it's used in Acne creams for chrissakes!) and it has a very short half-life when exposed to heat. That's gonna be OK in a dishwasher. SteveBaker 17:33, 15 September 2007 (UTC)

Tomato stain will eventually wash out of a plastic container (or a plastic dishwasher interior!) but it takes a long, long time. My wife and I go round and round about this each time I rinse tomatoey things before putting them into our plastic-tanked dishwasher; she doesn't. Probably for this reason alone (domestic tranquility), I'd go stainless steel the next time ;-).

Atlant 14:42, 17 September 2007 (UTC)