Wikipedia:Reference desk archive/Science/2006 July 19

From Wikipedia, the free encyclopedia

Humanities Science Mathematics Computing/IT Language Miscellaneous Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions at one of the pages linked to above. This will insure that your question is answered more quickly.

< July 18 Science desk archive July 20 >


Contents

[edit] Beer Gut

Do men store fat underneath their abdominal muscles resulting in the taught appearence of a beer gut? Further more is this a defining difference between the way men store fat in the stomach area and how women store fat (ontop vs underneath the abdominal muscles) resutling in differencent appearnces. Thanks!

I'm almost certain that fat is stored on top of the abs. You can imagine how long a very fat man's abdominal muscles would need to be to stretch all the way around his 'beer gut'. As a general tendency, men tend to carry excess weight around their stomachs, while women tend to carry it around their hips, thighs and buttocks. So yes, there is a distinction between the sexes. BenC7 02:47, 19 July 2006 (UTC)
Fat stored between the organs (don't recall the word for it) needs to be considered too. I've seen a lot of big beer guts up close and they're not all surface fat; I believe those gentlemen were carrying a lot of fat between their organs. IIRC, some recent studies have further clarified the difference in cardiac incidents (higher statistics among 'apples' - people who were fat around the gut - than 'pears' - people who stored fat on hips and thighs) with the discovery that fat between the organs resulted in correlated with higher rates of cardiac incidents.--Anchoress 03:20, 19 July 2006 (UTC)
The phrase you can't recall is "visceral fat". - Nunh-huh 08:48, 19 July 2006 (UTC)
When I as a schoolboy dissected rats in biology class, the fat rats had most of their fat inside the body cavity and comparatively little on the surface. When I measured my % body fat with one of those handheld machines, I was horrified to get a figure of 26%, yet I am if anything below average body mass index. I am sure that in most of human history humans were a lot thinner, and so of course we evolved to cope with a thinner body weight and not what is regardecd as normal now. That must be why animals (and humans) who are fed restricted calories live so much longer. --62.253.48.91 09:27, 19 July 2006 (UTC)
One one of those plastic surgery shows, they did a liposuction on some guy and the lady doing it mentioned that unlike women, men have fat both on the inside and outside of the abdominal muscles. --Kainaw (talk) 14:20, 19 July 2006 (UTC)


Fat is stored both over the abs as you might think but also under the abs in the structure called "omentum" which drapes like an apron over the vital organs. Doctors are now telling us the dangers of having too much omentum fat. Women also have omentum but tend to put their excess weight on hips and thighs.

[edit] Sun Poisoning

How long, on average, do the effects of sun poisoning take to subside?

Note this user means sun burn. Please read our article and the links on it. --mboverload@ 03:43, 19 July 2006 (UTC)
This is a difficult question to answer because different people are affected in different ways to sunburn and thus it may take longer/shorter for them to recover. For example someone with very pale skin may not recover as quickly. Recovery time is also based on the total exposure as well as the use of additional aids (after sun, milk, etc). Sorry i could not give a definative answer but in my personal experience sunburn doesn't tend to last any more than a couple of days. Benbread 10:36, 19 July 2006 (UTC)
Note, the question is about sun poisoning, not sunburns. There is a woman who works in the hospital here that is dangerously addicted to sunbathing. She spends all day Saturday and Sunday laying out on the beach. She goes to the tanning booth every night. On long weekends, like the last July 4th holiday, she spent 4 full days laying out. She isn't tanned, brown, bronze, or black. She is purple. Often, the poisoning is so bad that she needs crutches to walk. Now, to get near an answer to the question... When she gets that bad, it takes at least a week before she can walk without crutches again. --Kainaw (talk) 13:07, 19 July 2006 (UTC)

[edit] mango madness

have any of u guys broken a mango seed into twop pieces ? well i did and i found something that looked like a big form of a cashew nut . it tastes a bit sour and is white in colour any idea what it is called and is it used in making food .

See mango and cashew. They belong to the same family, Anacardiaceae. A little warning. I once ate a bit of a raw cashew nut (which is also contained in a much larger fruit) and my mouth was on fire, which took several hours to subside. It contains the skin irritant Urushiol, which is also found in another family member, poison ivy. The mango article only says the skin contains a bit of it. Nothing on the 'nut', it seems. DirkvdM 06:48, 19 July 2006 (UTC)

[edit] Run Out of Semen

1. About how much semen (in mL, if you don't mind) do the human testes hold?

2. How many orgasms would an average man have to have in order to run completely out of semen? Not completely as in run out forever, completely as in his body cannot produce it fast enough and there simply isn't any left in the testes.

Thanks, 68.52.187.248 08:03, 19 July 2006 (UTC)

For 2, there are many variables. Strength of the orgasm, strength of the PC muscles, and just different men. --mboverload@ 08:48, 19 July 2006 (UTC)
Note that for orgasms is close succession, the volume of ejaculate tends to go down with time. I suspect (though haven't confirmed empirically) that you would just see smaller and smaller volumes with lower sperm count, rather than 'running out' completely (see asymptote). For your reference, most of the fluid in an ejaculation doesn't originate in the testes at all—the bulk is from the seminal vesicles; you can check out our article on semen for a breakdown, as well as this external site. TenOfAllTrades(talk) 13:09, 19 July 2006 (UTC)
Would be a fun experiment, though. :) Or would it? DirkvdM 19:24, 19 July 2006 (UTC)
Depends. Probably 4 for the average man in a few hours? --Proficient 03:16, 20 July 2006 (UTC)

[edit] disasters

can u tell me how man's interaction with the environment has resulted in the following:

  1. deforestation and soil erosion causing droughts and floods
  2. faulty construction practises leading to disastrous impact on life and property during cyclones and earthquakes
  3. water scarcity in rural and urban areas
  4. uncontrolled growth of settlements on hazardous hill slopes causing landslides

i would appreciate it if you could give me links to sites that have graphs and stats on this pertaining to the Asia pacific region especially the Indian subcontinent. actually just give me links for every thing. i know that you guys don't like helping out with school work but this is for a project .so i don't want complete answers , only clues and links to guide me in the right direction.--Mightright 09:04, 19 July 2006 (UTC)

Actually all those things you list you answered yourself =D As for stats and graphs, the only real stats to get would have to be on deforestation and the amount of silt that passes through rivers near those areas. There are tons of sites about it. Good luck! --mboverload@ 11:08, 19 July 2006 (UTC)

If you put every one of those bullets into a Google search, you would gets lots of stuff. The tough part about a project is organizing and winnowing down scads of data. That is what they want to teach you, as it is one of the most important skills in the modern world. --Zeizmic 12:01, 19 July 2006 (UTC)

Many economical uses of land, for short term profit potential, have long term impact on other users. Thus there is conflicting interests out there on how best to use the land.
Western USA and other places appear to have non-stop wild fire problems, that did not exist decades ago. Is this the result of human land use, that had it been different, we would not be having this problem? Or is it related to global warming?
Hurricane Katrina reputedly did MUCH more damage than had the wet lands not been drained. The function of wet lands includes draining off the wetness of bad storms, so as to protect inland from the big blows. But wetlands had been drained for human development, which meant big blows now do more damage. Another case of conflicting interests, some more interested in short term economic impact than others.
Nigeria and other nations, used to be net exporters of timber and other agricultural products. Now they are net importers. This because the people cut down trees to make more farmland, used the land more intensively than it capable of sustaining, became wastelands, with growing deserts, not able to sustain as many people, they got serious problems ahead, unless they can reverse the process.
Population can expand beyond local capacity to support that population, in good times and bad.
People can buy real estate, based on current conditions, ignoring seasonal patterns.
World wide, people can buy, or work on real estate, who lack understanding of the long term effects of what they do to change the environment.
User:AlMac|(talk) 18:20, 19 July 2006 (UTC)
For another example, the forest fires on Borneo in the early nineties (I believe it was) were most probably caused by deforestation, leaving behind sawdust and such that eased the start of a fire and making the forest dryer, easing the spread of the fire. DirkvdM 19:30, 19 July 2006 (UTC)

[edit] Vitamin C impact on Fats

Hey, i was reading http://www.webterrace.com/fat/burning.htm which suggests that Vitamin C "reduces the effectiveness of fat", on reading this it seemed to me like a load of rubbish. I had a fair look through the Vitamin C article which suggests nothing of the sort, though it's possible i have missed some information. Does anyone have any knowledge on weather Vitamin C can be used for this purpose or do you think it's yet another hyped-up fad? Thanks greatly Benbread 09:18, 19 July 2006 (UTC)

First of all "effectiveness of fat" sounds rather fishy, and of course, there's no such thing as "fat burning food". What the author might be getting at is that sour fruit can decrease the rate of absorption of nutrients, which could aid in losing fat (see Glycemic index). Food with different pH than the blood (which is about 7.34-7.44 I think) isn't absorbed as that could lead to acidosis. Jack Daw 17:22, 19 July 2006 (UTC)
Normal foods can be acidic (like the acid in soft drinks); that does not cause acidosis. I googled "vitamin c fat metabolism" and came up with these: http://lpi.oregonstate.edu/infocenter/vitamins/vitaminC/ and http://lpi.oregonstate.edu/news/vitc_lipid.html - Cybergoth 02:17, 22 July 2006 (UTC)
I didn't suggest eating acidic foods cause acidosis, I said if the body were to absorb it, then there would be acidosis. I may be wrong of course. Thing is I read about a year ago in a book about GI that eating acidic foods slows absorption, and how this would be beneficial on glucose metabolism etc... Anyway there wasn't any explanation why acidic foods would slow absorption, I'm simply assuming it has something to do with blood gas homeostasis. Again, I may assume wrong. Correct me if I am. Jack Daw 10:18, 22 July 2006 (UTC)
You would have to eat a lot of acid to overcome your body's ability to buffer the acid. I don't know if acidic food slows absorption, or how it might do that. - Cybergoth 17:51, 22 July 2006 (UTC)

[edit] humidity

what s the meaning of humidity.....

See humidity. Humidity is the concentration of water vapor in the air. —Mets501 (talk) 14:04, 19 July 2006 (UTC)

[edit] Train Question

Railroad tracks are made of steel, but they are not painted, and I do not think that they are covered with any other rust preventative, and yet they do not appear to rust. If they did, surely the trains would be in danger of derailing on rails liable to collapse upon themselves. I am told that rails do not rust as long as they are in active service because the wheels polish them. Fine, but they do not polish the sides (other than the flange). So, how come this steel, placed on the ground, in full exposure to the elements, does not rust?--MrFishGo Fish 13:51, 19 July 2006 (UTC)

I walk across over railroad tracks nearly every day. The tops are shiny because the trains go back and forth a few times a day. The sides are so caked with dirt and grease that you can't tell if there is rust in there or not. Also, the rails to fail. It was at least six months ago, I'm not sure. The train stopped and blocked our main crosstown street because a rail cracked under it. Then, to make matters worse, a cement truck driver wanted to reverse and try to get around the holdup before his cement went solid. He must have been a bit retarded because he dumped the cement instead of going in reverse - I seriously doubt the control to dump the cement is next to the gearshift. So, it was a real mess, which is why I remember the track cracking. --Kainaw (talk) 14:18, 19 July 2006 (UTC)
Yes yes, I know. Still, a crack here and there is not what I would expect. There are rails that have been sitting in the rain and snow for over 60 years in some cases, and they are still active and safe.--MrFishGo Fish 14:52, 19 July 2006 (UTC)
There's actually quite a bit of track maintenance that goes on. Rails are inspected (and replaced if necessary) on a very regular basis. Steel rails in cold climates become brittle and are prone to cracking (it happens every winter in Canada). Nevertheless, tracks that see relatively little traffic will last for a long time. You get a semi-protective layer of rust, grease, and other grime, and track beds are designed to have good drainage so that the rails are never kept in standing water. Rails are made from very heavy steel – 120 pounds per yard or about 60 kilograms per meter – and takes a lot of punishment to wear down. TenOfAllTrades(talk) 15:38, 19 July 2006 (UTC)
Simple, Not all steel degrades like the body of a low quality automobile after a decade of northern driving! I first realized this after visiting the New River Gorge Bridge in West Virginia, which is apparently made of Cor-ten steel. According to the sign adorning the bridge (and alluded to in the Cor-ten article,) rust actually creates a protective layer on the surface, preventing the interior from oxidizing. Maybe the same principle is applied to train tracks? --Jmeden2000 20:16, 19 July 2006 (UTC)
Thanks, folks. I have been an absurdly die-hard railfan for my whole life, but I never could figure this one out.--MrFishGo Fish 15:25, 20 July 2006 (UTC)

[edit] how to calculate SMR using poisson or bayesian apprpaches

please could someone explain how to calculate standard mortality rates using either poisson or bayes methods to produce a more valid SMR. I discovered some studies used one of this approaches for the statistical smoothening of their SMR. however, they were abit vague in their explanation on how its done. I would like to know if this analysis can be done using excel or SPSS.

[edit] Why do we prefer room temperature?

While our "inner" temperature is around 37.6 degrees (Celsius) or so, most people prefer temperatures around 20 degrees. Why is this? Since our bodies constantly have to work to maintain optimal "inner" temperature, shouldn't we be more comfortable with temperatures at that very level? Jack Daw 14:26, 19 July 2006 (UTC)

I don't know why 20 (or any other specific number) is favored, but one factor is that the body can't stop generating heat. Even resting there is some internal activity that coincidentally generates heat and this is far more true when active. In order for this to be dissipated, the external environment must be cooler than the temperature the body wants to maintain, or we would start to heat up above what is optimal. In hot environments, sweating delays the process by carrying away heat through evaporation rather than just conduction, but ultimately the body will function best in environments that are cooler than it wants to be. Dragons flight 15:15, 19 July 2006 (UTC)
The simplest explanation would be that our primate ancestors were most well adapted to a natural environmental temperature similar to room temp--natural selection favored those that could best regulate internal temperature, balancing metabolic needs and energy storage, but with enough ability to withstand variations in external temperature. 20C or 72F probably "feels" most comfortable because it exists as an energy output minimum for humans--requiring little thermogenic acitivity (shivering) and little heat-dissipating activity (sweating, finding shelter) while allowing efficient energy storage and maximal conservation of vital nutrients. Just my educated guess...these same reasons would determine why lab mice prefer 78F and moose are comfortable in Canada in the winter. -- Scientizzle 16:28, 19 July 2006 (UTC)
You could also reverse this. We evolved in temperatures of around 20 C, so our bodies evolved to function best at that temperature, so that's what we find most pleasant. Well, most people. I must be an aberration (as many people will acknowledge :) ) because I prefer temperatures around 30 C. At the moment I'm in heaven. Alas, being Dutch, most of the time I'm in hell (nice practise for the afterlife :) ). DirkvdM 19:36, 19 July 2006 (UTC)

I think it's basically the same question as "Why can we see visible light?", the answer being "Because we evolved in an environment where most of the EM radiation was visible light" --Bmk 02:34, 20 July 2006 (UTC)

As an aside, high humidity, which is often present when it's hot, seems to make it generally uncomfortable. BenC7 03:07, 20 July 2006 (UTC)
I have to question the question. Do "most" people really prefer 20 degrees C? I think temperature preference has a lot to do with the temperature one is most accustomed to; that is, people from cold climates likely prefer cooler temperatures than people from hot ones. Most of the people using English Wikipedia probably are accustomed to temperate climates (and probably have climate control as well), but it does not necessarily follow that a person from sub-Saharan Africa or from the Yukon Territories would prefer the same temperatures. --Ginkgo100 talk · contribs · e@ 04:30, 20 July 2006 (UTC)
Very true of course, I suppose I was referring to people in similar cultures, such as European and North American. Myself I love warm temperatures outside, but inside I can't stand it to be more than 25 degrees. Jack Daw 10:21, 22 July 2006 (UTC)

[edit] lightweight computer system

what is lightweight computer system? what is "lightweight"?

It could mean many things. Can you tell us more about the situation? Gerry Ashton 16:24, 19 July 2006 (UTC)
It could simply mean - er - lightweight, as in not heavy. Our article thread (computer science) says "Many modern operating systems directly support both time-sliced and multiprocessor threading with a process scheduler. The operating system kernel allows programmers to manipulate threads via the system call interface. Some implementations are called a kernel thread, whereas a lightweight process is a specific type of kernel thread that shares the same state and information" Does that answer your question? If not, perhaps you can supply more context.--Shantavira

[edit] Bird: Ostrich Skeleton.

Are the bones of an ostrich solid because it is a flightless bird. (A penguin has solid bones and is flightless). Or are they hollow like most other birds?

According to [1], some are hollow, some are solid, and some have thick walls. --Kjoonlee 02:54, 20 July 2006 (UTC)
Oops, forgot to mention: the link above contain images that might be disturbing. --Kjoonlee 09:14, 20 July 2006 (UTC)

[edit] pH balanced

What the heck does pH-balanced mean? I've often seen this in the decription of consumer products such as shampoo. Does it mean nuetral? Does it mean buffered? ?? ike9898 16:45, 19 July 2006 (UTC)

Try this. —Mets501 (talk) 16:53, 19 July 2006 (UTC)

[edit] Can you tell me the legally correct way for a licensed nurse to take a telephone order form a physician and how should it be documented in the resident's chart. This is in a long term care setting.

Can you tell me how a licensed nurse should take a telephone order from a physician and how it should be documented in a residents chart? This is in a long term care setting.

Don't they teach that in nursing school? User:AlMac|(talk) 18:37, 19 July 2006 (UTC)
This is a legal question. Perhaps you should ask a licensed nurse in your jurisdiction. Peter Grey 21:02, 19 July 2006 (UTC)
It's a legal question for which the answer will differ depending on local laws, and so you need a local answer. And there may be additional institutional policy restricting such orders. In some places, an LPN (licensed practical nurse) isn't permitted to take a telephonic order, while RNs (registered nurses are). In most places the nurse simply writes the order and signs it as a "Telephonic order from Dr. Hossenpfeffer". Depending on the order, a witness may be required (i.e., two nurses who heard the telphonic order both sign it), and in most instances, the order must be countersigned by the ordering physician within a certain time. - Nunh-huh 05:42, 20 July 2006 (UTC)

[edit] Electricity

Why does electricity passing though air throw off so much light, and no light when passing through metal? I didn't see an answer at electricity. -Quasipalm 18:31, 19 July 2006 (UTC)

My guess is that it's because the electrical resistance of air is much greater than that of metal, which means more energy will be dissipated as heat, which will cause the light. —Bkell (talk) 18:58, 19 July 2006 (UTC)
More specifically, it's because air must be ionized to let appreciable current pass, whereas metal need not be because the electrons in a metal are not bound to any particular atom and are thus capable of moving long distances without needing to be removed from one. Eventually the electrons and ions will recombine, and that's what's producing the light. The air is not, necessarily, incandescent. --Tardis 20:16, 19 July 2006 (UTC)
More info at Arc lamp. Melchoir 19:14, 19 July 2006 (UTC)
Light can be produced by electricity passing through metal--this is how your standard incandescent light bulb works. -- Scientizzle 19:42, 19 July 2006 (UTC)
Bkell is right. To add to that, the electrons in metal are only loosely bound to their molecules, so it it easy to make them move, producing electric current. The electrons in the gas molecules that make up air are tightly bound to their moleculse. A good deal of energy must be supplied to an electron to get it to leave one gas molecule, and when it arrives at the next gas molecule, it gives up the energy in the form of light. Gerry Ashton 20:19, 19 July 2006 (UTC)

[edit] Atomic attack on the moon

If a state-of-the-art nuclear warhead were propelled into the moon, what sort of damage would it inflict, roughly speaking? Would it influence its orbit in any way? Would it dramatically alter its appearance? Bhumiya (said/done) 19:29, 19 July 2006 (UTC)

  1. It would make a crater roughly equivalent to that of a terrestrial nuclear detonation.
  2. In any way? Yes. In any significant way? No. There's not enough force exerted on a planetary scale.
  3. Nope. Again, a question of scale.
— Lomn | Talk 19:39, 19 July 2006 (UTC)
After edit conflict:
An answer can be found at Space: 1999, a tv series that started with a huge nuclear dump exploding and sending it off into space. This, however, is impossible. On a human scale, a nuclear explosion is pretty dramatic. On a planetary scale, it's a mere blip. We are insignificant. A wonderfully humbling thought. DirkvdM 19:46, 19 July 2006 (UTC)
Not that this has any scientific origin, but what if we alter the question to include "the detonation happens slightly below the moon's surface"? The problem with a nuclear blast on/above the surface is that as the matter turns to energy, not much of the energy is converted to any sort of force, most is just deflected into space. If it were to occur just far enough below the surface as to propel matter away from the moon it could have a more substantial effect (the most likely i could think of is propelling meteors toward Earth).--Jmeden2000 20:04, 19 July 2006 (UTC)
Again, it'll be more-or-less terrestrial and you'll get a subsidence crater. I doubt that anything large enough to survive atmospheric reentry at Earth could clear the Moon's escape velocity from such an explosion. — Lomn | Talk 20:57, 19 July 2006 (UTC)
Less-related fun fact! "State of the art" nukes will get you less effect than the old-fashioned ones! The largest nuke on record, the Tsar Bomba, was detonated back in 1961. Modern nukes have significantly lower yields. — Lomn | Talk 21:06, 19 July 2006 (UTC)
Well, that's because it isn't technically difficult to make a large explosion, if you don't mind how big the bomb is and you already know how to make a hydrogen bomb. The difficulty comes in if you want it to fit the warhead inside a very small space (so that you can put twelve of them on the end of one missile, for example). --Fastfission 01:41, 20 July 2006 (UTC)
More importantly, it's an excuse to actually use nuclear bombs. Too big a bomb cannot really be used. If you manage to make it smaller you can call it a 'strategic bomb'. Of course, other people can pick up this technology and then you can use that as an excuse for 'war on terrorism'. The arms industry is having a ball. DirkvdM 08:45, 20 July 2006 (UTC)
Good points. I should have said something like "modern nukes are built to smaller scales", because it's certainly not a know-how issue but rather one of utility. Either way, an old clunky 50MT bomb will make a bigger hole than a new shiny 1MT bomb. — Lomn | Talk 15:40, 20 July 2006 (UTC)
A sub-surface nuclear detonation is pretty similar in its results to a meteor impact. So, using a meteor impact simulator with parameters to produce a 100 megaton impact energy (roughly the power of the Tsar Bomba), it'll produce a crater about 3,000 meters in diameter, and about 650 meters deep. You'll be able to see the crater with a good telescope, but it'll be easy to confuse it for other, similiar craters. --Serie 23:23, 19 July 2006 (UTC)
The more interesting question would be the differences in behavior in terms of the relative lack of atmosphere. In the end I suspect it would make it less of an issue than it would be on earth — no oxygen to feed the fireball, no wind to kick around the fallout. Nuclear weapons in the upper atmopshere and outer space have somewhat different properties than ones on Earth, but most of them would be uninteresting as far out as the moon (i.e., I don't know if you'd get EMP effects). --Fastfission 01:40, 20 July 2006 (UTC)
A big difference is the lack of Bremsstrahlung. It's what happens when massive ions suddenly come to an almost complete stop in air.
To answer the original question, even the massive Tsar Bomba released 1 millionth the amount of energy of a huge asteroid. The moon gets hit with asteroids all the time, and with no air, they hit quite hard. A nuclear bomb would barely be noticable. 71.199.123.24 08:32, 24 July 2006 (UTC)

[edit] Jumping into water

Does anyone know what the approximate maximum height that someone can jump into water and survive is? In this hypothetical situation, what would be the best way to jump - feet first, I presume, splaying arms and legs once under water to try and slow the rate of descent? — QuantumEleven 20:39, 19 July 2006 (UTC)

The max height is going to move quickly into the realm of improbably dumb luck (much the same as how a very few people have survived falling several thousand feet without a parachute) -- if you can reach terminal velocity, then it doesn't really matter where you start from. Anyway, feet-first will be the most survivable position, but you'd need to shift to that as late as possible (you'd want to be max-drag for most of the fall to lower the terminal velocity). Feet-first maximizes the amount of body the impact can pulverize (reducing the remaining kinetic energy) before you get to vital organs. You're not going to be worried about spreading your legs underwater; they'll be jelly at that point. — Lomn | Talk 21:02, 19 July 2006 (UTC)
Do you have any citations for that info, Lomn? Because I'd heard that above a certain height it's very unlikely to be able to survive a fall into water. And as for the parachute angle, don't forget, water can kill you just as dead as impact. Falling into something really soft on land and breaking your ankles is safer than falling into water and breaking your ankles. QuantumEleven is right about trying to slow your rate of descent in the water, because if your legs are broken you won't be able to swim or tread water, and the impact will probably knock the wind out of you, which means that if you're too deep you'll drown before your natural buoyancy will be able to cause you to surface.--Anchoress 21:10, 19 July 2006 (UTC)
Here's a couple of land-fall w/o parachute survivors and people surviving off the Golden Gate, though the latter might not be a terminal velocity case. However, all that said, I don't dispute very unlikely to be able to survive at all -- that's just not the same statement as can... survive. Note, however, that in the Straight Dope link (and many others), a lot of these falls (like the 1963 "into the Pacific" one, which would at first glance seem to prove my point) suggest extra drag, like an incompletely opened parachute rather than a straight-up no-parachute scenario. — Lomn | Talk 21:41, 19 July 2006 (UTC)
Also, my back-of-the-envelope calculations suggest that the impact speed of the referenced Golden Gate survivor was about 90 mph. Optimal human terminal velocity is about 120 mph, just for reference on how close this scenario is to reaching my no-upper-limit suggestion. — Lomn | Talk 21:47, 19 July 2006 (UTC)
Well I was hoping for statistical info rather than specific examples; I get what you're saying about 'can possibly survive', and I think we agree, but I think in the instance of high water landings (like GGB, which IIRC is considered one of the bridges you're most likely to die jumping from), I think luck (as in whether help is near) plays a huge role. The main problem as I see it is that even if you survive the impact, you are unlikely to not have broken bones, and even a broken arm or toe can mean certain death if the water is sufficiently rough and help is not pretty much instantaneous. So I guess maybe I'm having a different discussion here... it's not whether or not you can survive the fall, but whether or not you can survive the two to sixty minutes after the fall. Which isn't really what the OP was asking, lol. Maybe I'll just shut up now. :-) --Anchoress 22:12, 19 July 2006 (UTC)
I once saw an interview with someone who had jumped off a burning oil platform. One is not supposed to survive that, but he got lucky. I don't know how high it was. Oil_platform#Large_platforms says the highest ones are hundreds of metres high, but I suppose most are less than 100 m high. If anyone knows this, please add it to the article. DirkvdM 08:59, 20 July 2006 (UTC)

[edit] nerve endings

It is a common thing for people to say (at least here in england) that when you get your feet massaged that "all of your bodys nerve endings are there" also this applies to your scalp during head massage. however looking at my anatomy book on it appears that for the scalp you only have the C2 nerves connected and for feet L5,L4,S1 and a few others. Now I'm not knocking massage and I really like the concept of "chi energy" but could I have some clarification please!

I would trust the anatomy book. The most literal interpretation of "all your body's nerve endings [being] there" would suggest that you'd be numb everywhere else on your body. The simplest thing for the body/brain to do is to have different nerves going to different places. Intuitively, if all nerves sent half their endings to your scalp and have to your feet, one might expect that touching everywhere on your feet (say, due to a shoe) would make you simultaneously feel as though your scalp was being touched as if you were wearing a hat (because it would be the same nerves firing in either case). Digfarenough 22:13, 19 July 2006 (UTC)


In looking further into it at www.apparelyzed.com/dermatones.html it seems interesting to me that head massage stimulates C2 and also the Trigeminal Cranial nerve (v) which seems a direct root into the brain. However the feet seem to be only part of the peripheral nervous system. Still there is no "all of the nerve endings are there and are connected to various organs" proof. One only has to cut the L5,L4 and S1 nerves and surely no stimulation of anything will then occur! Perhaps reflexology works by causing relaxation due to the pleasure which is in effect stimulation of the parasympathetic nervous system.

Most educated people would be a lot more receptive to alt med stuff if they didn't misuse scientific terms. No scientist or doctor would think of arguing about a chi claim, but the "nerve connection" claims of foot reflexology are ignorant drivel, pure fantasy. alteripse 12:48, 20 July 2006 (UTC)

[edit] What Do You Think Of This

http://mobilemag.com/content/100/354/C8115/ you will probably have to paste it in your browser.

Bollocks. Melchoir 23:00, 19 July 2006 (UTC)
HHO gas being what precisely? a H+ OH- plasma? Xcomradex 23:20, 19 July 2006 (UTC)
H-h-ho! Vitriol
See Brown's gas. And yes, it's complete bollocks. —Keenan Pepper 23:37, 19 July 2006 (UTC)

"Of course, none of this has been confirmed, so it's hard to say whether Mr. Klein's invention is a) for real, b) actually usable or c) a complete hoax." No, it's easy to say. Complete hoax. I note the video says his demo car is a water/gas hybrid, whereas the article claims a water-only vehicle is possible. So why doesn't he show it? FOX NEWS circus for the masses, including Congress. He has filed for a patent, not that he has recieved one. For more see http://hytechapps.com/ of Clearwater, Florida one of his sites. See http://www.magnegas.com/ by Ruggero Maria Santilli who also discusses HHO, who seems to have some connection to Klein (unconfirmed). See Ruggero_Maria_Santilli which links to notes for a draft by User:Hillman//Ruggero Maria Santilli . Santilli touts Magnegas(TM) which seems to be same as HHO. Santilli has some patents. Why can't they get anyone to confirm their claims? --GangofOne 00:05, 20 July 2006 (UTC)

Wow - that is the most elaborate piece of crud I have ever seen! Amazing! Was that FOX news broadcast a hoax? If not, my small respect for Fox just burned up as fast as HHO gas. This isn't the first time someone has claimed to have found a "new form of water". See polywater. That one stuck around for a while. LOL - I just started reading their "scientific paper", in which they even claim to have found a new kind of bond - a "magnecular" bond, which forms "magnecules" instead of "molecules". H-h-ho indeed --Bmk 00:27, 20 July 2006 (UTC)
me too. even worse, the paper has slipped through peer review, and is now in press. what suprises me is the flimsy evidence they use to support their point, and they don't even interpret the IR data. Xcomradex 00:39, 20 July 2006 (UTC)
What I wonder is, if his welder hots up everything else, why does it specifically not burninate your finger? Vitriol 08:36, 22 July 2006 (UTC)
This has actually come up before at WP several times. Yes, it is complete BS. ---CH 09:15, 23 July 2006 (UTC)

[edit] Stingy hot-weather eyes

So when I was sitting around my eye suddenly started stinging like hell, right? I thought it might be sweat but then I thought any caveman stumbling around with stinging sweat in his eyes would be pretty dead by now. It's real hot here, like 37 degrees (well, by brother says that, and I'm not sure his sources are reliable ;)), so could it be the hot weather is making my body conserve water, and concentrating and thus increasing the salt level in my sweat? Vitriol 22:45, 19 July 2006 (UTC)

Are you sure it wasn't sunscreen?--Anchoress 23:03, 19 July 2006 (UTC)
I barely go out :P Vitriol 23:10, 19 July 2006 (UTC)
It was probably sweat. It stings. I don't know why it didn't wipe out cavemen. --Ginkgo100 talk · contribs · e@ 04:34, 20 July 2006 (UTC)
That's why we have eyebrows. I suppose as we got less physical (and more 'mental') we needed less protection against the sweat. Considering my receding hairline I must be getting very intelligent. :) DirkvdM 09:05, 20 July 2006 (UTC)

[edit] Nuclear Fusion

How is enrgy in a fusion power plant obtained from a fusion reaction. -- 68.120.230.42 23:47, 19 July 2006 (UTC)

  • It isn't, that's why we don't have fusion power plants, just Tokamaks--64.12.116.74 23:50, 19 July 2006 (UTC)
That's right, cut across me. Vitriol 23:51, 19 July 2006 (UTC)
Magic! Vitriol 23:49, 19 July 2006 (UTC)

Hey - enough ripping on fusion power. True, we do not currently have any fusion power plants per se, but many fusion reactors still obtain energy from fusion reactions. The most common fusion reactions used in reactors are deuterium-deuterium reactions and deuterium-tritium reactions. Basically, you strip all the electrons off of the isotopes, then slam the nuclei together. If you slam them together with enough energy to overcome the coulomb barrier, then the nuclear particles rearrange into a lower energy state, typically D+T ==> Helium + neutron, or D+D ==> T + proton. And a heck of a lot of energy, which comes from the cumulative decrease in energy of the strong force bonds between the nucleons. See nuclear fusion for more info. --Bmk 00:35, 20 July 2006 (UTC)

Well, they obtain energy, but they don't produce any net energy, as I understand it. --Fastfission 01:49, 20 July 2006 (UTC)
Not yet... --Bmk 02:31, 20 July 2006 (UTC)
Yeah, they've only been promising that it's right around the corner for what, three decades? --Fastfission 14:43, 20 July 2006 (UTC)
We're about twenty years from practical nuclear fusion, and have been ever since the early 1960s. --Serie 22:58, 20 July 2006 (UTC)
The question could mean two things. One is where the energy comes from, which Bmk already answered. The other is how it is used to produce electricity, which is through heating water and letting the resulting steam drive a turbine. As for the net result, that's a matter of size. A plasma (an extremely hot mixture of particles flying around in a magnetic torus-shaped 'corset') needs to be maintained. The bigger the thing is the better the balance between energy input and output (I suppose this is because of the input is related to the surface of the torus (power two) and the heat is related to the content (power three)). But before you build such a big one you want to know what the best design is, and that is what the present ones are for - for research, not energy production. It seems that we now pretty much have the technology. It just takes some government to take the risk of being the first one to try. The investment would be huge and the outcome uncertain (as always with something new). That's the problem here - it has to be big. You can't start with a small one to try it out (except for research that is). DirkvdM 09:18, 20 July 2006 (UTC)
True! In fact, some governments have already stepped up. See ITER! Why is everyone so darn impatient with fusion :) ? What are a few decades in the face of a problem that could revolutionize our economy and our interaction with the environment? Once we solve the problem, it could eventually eliminate all other power sources - negligible pollution (assuming we start making hydrogen/electric cars). Just give it some time - that's what i say. --Bmk 16:38, 20 July 2006 (UTC)

Awesome thanks for your answers.