Wikipedia:Reference desk/Archives/Science/2006 November 1

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November 1

For Better Bio Gas Yield...??

I would like to know the yields of bio gas by anaerobic digestion of Food Wastes(fruit juice,Souce & Jam industry waste) Vs. Brewery industry waste (using malt)...?? Need methane to CO2 ratios (Approximate values) in both cases...!!

Thank You... Malinda

Phospholipase A2

What are the main functions of Phospholipase a2 enzyme. Which r its iso-forms

What happened when you used the "search" box on this (or indeed any and every) page on this site to look for the term "Phospholipase A2"? DMacks 05:43, 1 November 2006 (UTC)

Erotic asphyxiation question for evolutionary biologists, endocrinologists, and maybe embryologists

Hi, I'm thinking(and probably oversimplifying but please be tolerant) that our remote ancestors had radial symmetry which then lessened into mere bilateral symmetry(which is nostly on the outside now our inside organs aren't too symmetric anymore). If the mouth and anus are identified as "historically" isomorphic and symmetrically opposite, then things in the neck like the Adam's apple and thyroid could be presumed to be symmetrically opposite things like the genitals and prostate(in males), if one allows for blurring of the exactness through long evolutionary periods. But the Adam's apple and the genitals in a male both grow larger during puberty. These factors make me surmise that the same hormones, or perhaps hormones that are descended from the same original hormones and could still be similar, regulate the development of structures and nerve endings in the neck and private parts. So here is my question:

• Could hormones(perhaps mainly from the thyroid) which regulate the development of structures in the neck, so closely mirror hormones(perhaps mainly from the prostate) which regulate the development of the genitals in the male and the ability to feel sexual pleasure in that region, that sexual pleasure can be felt in the neck region, causing the pleasure of erotic asphyxiation, hickeys, and the giving of fellatio?--Of course much of the above could be applied to females with the homologous organs. But I haven't read of erotic asphyxiation among women.Thanks,Rich 06:43, 1 November 2006 (UTC)

I am neither of the expert types listed in your heading but still feel confident to argue your hypothesis to sound unlikely. Remember that the move from radial to bilateral symmetry happened extremely long ago. So much more has happened till then. Just observe that not only mammals, not only vertebrates, but even insects are bilateral. I imagine that the endocrine system over this wide range of the evolutionary tree varies tremendously. Furthermore, even a radially symmetric animal such as an earthworm has a distinct mouth and anus. Trying to explain such specific behavior traits as which kind of sexual acts turns somebody on with such a coarse thing as hormones is a bit too blunt. I wonder if they are even hereditary -- if not it would point to psychological, i.e. environment-induced causes. Oh, and I think I have read somewhere that there are women who enjoy sexual play involving choking.That none of them are dumb enough to get killed in the process does not prove that there are none. Simon A. 12:55, 1 November 2006 (UTC)

(EDIT CONFLICT) First, the regulation of sexual maturity in puberty, and by connection the "adam's apple", is controlled by the sex hormones, none of which are secreted by the thyroid (or parathyroid) glands. Also, the thyroid is endoderm while the thyroid cartilage is mesodermal, so they "evolve" from different germ layers, and furthermore are on the same side of the trachea, which doesn't lend itself to the same kind of symmetry as the mouth and anus. It is unclear (to me) what you mean by isomorphism as it applies to the symmetry of the mouth and anus. I suppose they are both holes, but the nearby structures, the thyroid cartilage and thyroid to the mouth and the genitals and prostate to the anus, are not isomorphic in the sense you described. The sexual maturity of all of these organs is controlled, as I said earlier, by the sex hormones. These hormones are primarily secreted by the testes in males (with support from the adrenal glands, adipose tissue, even the brain), thus the prostate is not responsible for maturation of the "genitals", nor is the thyroid responsible for maturation of the "adam's apple". The sexual pleasure one might feel from the activities desribed is created in one place: the brain, and is summarily not due to any similarities, hormonal or otherwise, between the glands of the perineum and neck.Tuckerekcut 12:59, 1 November 2006 (UTC)

Where can a man go to just 'vanish'?

Suppose I was sick to death of society and the human race and decided to get away from it all, drop off the radar, find a nice place in the sun and look after #1 - where would be the best place to go? Are there any isolated, yet hospitable places left on earth these days? I don't fancy the idea of living on some moss-covered rock in the South Atlantic. --84.69.57.172 07:57, 1 November 2006 (UTC)

Kure Atoll, Palmyra Atoll and Laysan are nice this (and pretty much every other) time of year. Assuming you could give the United States Fish and Wildlife Service the slip, it would be just you, the birds, the coral and an occasional scientist. Rockpocket 08:51, 1 November 2006 (UTC)

It depends a lot on how much money you have to spend. There are lots of isolated places to live, but getting to them and having supplies brought in could be quite expensive. StuRat 15:02, 1 November 2006 (UTC)

You'd be suprised how much of the world is still wilderness. Just browse around on Google Maps and you'll see that human settlement really is the exception, not the rule. Even little old England has a great deal of untamed land. -- Chris 17:04, 1 November 2006 (UTC)

No need to look after me, I'm already doing that. DirkvdM 17:45, 1 November 2006 (UTC)

Though the NW Hawaiian Islands were made into a maritime reserve in June 2006.--Russoc4 17:51, 1 November 2006 (UTC)

Pitcairn. A country with a population of 45. No other habitation for hundreds of kilometres around and only an occasional small boat drops by because bigger ships can't approach it. "Leaving the island is hit-and-miss; one leaves when transportation happens by, not necessarily when one wishes to go." And you'll be living with the descendants of the mutineers of the Bounty, which is pretty cool. And if even that handfull is too big a crowd for you, it has a "nearly inaccessible interior" to get lost in. DirkvdM 18:43, 1 November 2006 (UTC)

Fully 10 percent of the population of Pitcairn island is now to be imprisoned for rape and indecent assault [1], in a new prison being constructed for the task... The long arm of the law reaches even there. --TeaDrinker 22:16, 1 November 2006 (UTC)

You are better off going to Henderson Island anyway; no-one there. Batmanand | Talk 17:06, 3 November 2006 (UTC)

There's still plenty of densely forested areas where a man could just disappear and live off the land, if he knew what he was doing. No shortage of food and water there. If you can make fire/shelter, know how to hunt/fish without using modern technology and are the kind of guy who looks at a deer and sees a month's-worth of food and a new pair of warm clothes, you'll be sorted. --Kurt Shaped Box 21:47, 1 November 2006 (UTC)

I'm not even sure he'd have to live off the land. Without paying rent, taxes, and utilties, a hundred thousand dollars could last for decades. I think the key thing is to always assume you're going to run afoul of local or federal authorities, and be read to move on a moment's notice. But, the further you live from the nearest highway, the less you have to worry about this sort of thing. -- Chris 21:53, 1 November 2006 (UTC)

I'd like to find an island solely inhabited by seagulls and, with my superior intellect and knowledge of their ways, rule over them as a living god! Muahahahahahaha!

Or at least hang out with them. I could catch fish, cook it and feed them - they'd probably think I was pretty cool for being able to do that. --Kurt Shaped Box 23:31, 1 November 2006 (UTC)

I'm glad I'm not the only one who daydreams about impressing seagulls! Pesapluvo 02:38, 2 November 2006 (UTC)

I'd like to be to great black-backed gulls what Irene Pepperberg is to African grey parrots. I have searched far and wide but no-one seems to have seriously studied human/gull interaction on a one-to-one basis (though Audubon alluded to it in some of his writings). --Kurt Shaped Box 07:05, 2 November 2006 (UTC)

Just wondering, Kurt, have you read Jonathan Livingston Seagull ?

The Statue of Liberty. Anchoress 04:25, 4 November 2006 (UTC)

Unabomber tried this, and he went nuts. I expect that after living in a tent for a few weeks, especially when its cold, that even the smallest and most squalid room will seem like paradise. I think lots of people do do this - but they realise that they would not be able to stick living off the land for long, and just buy or rent a small house or flat somewhere. You are most likely to be anomymous in a big city. Then there is the gypsy way of life. A few miles away from where I used to live, a man lived out of a lorry for a few years, and may be doing so still. I am very skeptical that you could live anywhere in the UK without being bothered by people.

Big Bang and Big Collapse

Has anyone postulated a Big Cycle, i.e., the point in the Big Collapse when it reverses direction and becomes the Big Bang and vice versa? Adaptron 10:40, 1 November 2006 (UTC)

What, some sort of Big Crunch!? Proposterous! ;-) Philc _T^E_C^I 11:22, 1 November 2006 (UTC)

Oscillating universe?--Light current 12:28, 1 November 2006 (UTC)

These links should do. However, note that these idea are now in contradiction with recent observation which show that the expansion of the universe is not decelerating but accelerating and hence likely to end in the Big Rip. Can it be, BTW, that we have no decent article on this? Simon A. 13:01, 1 November 2006 (UTC)

"Likely" is putting it a bit strongly. This crucially depends on the hypothetical dark energy being phantom energy, which at present is entirely speculative. And if it is phantom energy, it is not clear that its equation of state would remain constant until the bubble bursts.  --Lambiam^Talk 15:58, 1 November 2006 (UTC)

Agreed. Simon A. 19:58, 1 November 2006 (UTC)

I've heard it called the Big Chill. StuRat 14:58, 1 November 2006 (UTC)

I would expect that to refer to the Big Freeze rather than the Big Rip. Any evidence for the claim that this specifically refers to the Big Rip?  --Lambiam^Talk 15:58, 1 November 2006 (UTC)

Well, there's Ultimate fate of the universe, which summarises each of the leading theories. GeeJo ^(t)⁄_(c) • 15:00, 1 November 2006 (UTC)

of course there's always my explanation for the accelerating expansion. If we were falling into a black hole, wouldn't we see everything accelerate away from us? And wouldn't the acceleration be greater for objects further away? So wouldn't a Big Crunch be an explaination for the fact that we do indeed observe that? Alas, every time I put this theory forward, people start punching holes in it. It's pretty leaky now. But I made a controversial prediction that turned out to be correct, and the scientific community hasn't come up with a decent alternative yet, so that keeps me going. :) DirkvdM 17:52, 1 November 2006 (UTC)

And before any of that, you will die. And then the sun will die out. THen the Milky Way will merge with Andromeda and wreak havoc. Tbeatty 18:02, 1 November 2006 (UTC)

I think the Sun might still be around when the Andromeda Galaxy hits us. StuRat 19:29, 1 November 2006 (UTC)

You say hit us, but given the incredibily low density of galaxies (millions of miles between star systems) there wouldnt actually be much hitting involved would there? Philc _T^E_C^I 19:49, 1 November 2006 (UTC)

If you neglect the gravitational effects, then that would be true. With gravity, however, the two galaxies have a major effect on each other, although, Andromeda being much larger, it ends up winning, with the Milky Way being "consumed". Many of the Milky Way's stars will be pulled into Andromeda, and others will be flung into space. The super-massive black hole at the center of the Milky Way will coalesce with Andromeda's. StuRat 20:13, 1 November 2006 (UTC)

I don't know that there's as much gravitational viscosity as the black holes would need to pull that off; moreover, we don't even know that there's truly going to be a collision at all (as discussed in the article). --Tardis 22:14, 1 November 2006 (UTC)

Why do teeth have nerves?

Had a brief search on the 'pedia and rest of the intarweb, but no luck. My guess would be either that the nerves are needed during the growth of the tooth or are vestigial. Any ideas?

Part of the reason I believe is to deter us from biting down so hard that we shatter them. Even human jaws are strong enough to do that. Anchoress 13:21, 1 November 2006 (UTC)

Agreed. Or, more generally, from doing things with your teeth that might be harmful to them. StuRat 14:55, 1 November 2006 (UTC)

Like biting newbies too hard?--Light current 16:01, 1 November 2006 (UTC)

So that we can feel if something is so hot or so cold that touching it with your toungue/throat etc.. will cause a burn. Philc _T^E_C^I 14:22, 1 November 2006 (UTC)

Don't you think the lips would be a better bet for that? Anchoress 14:25, 1 November 2006 (UTC)

Yeh, and they are, but surely it makes more sense to have feeling in your teeth aswell, I wasn't saying it in preference to other ways of feeling, but in conjuction with them. Philc _T^E_C^I 14:28, 1 November 2006 (UTC)

This is a neat link. [2] We should do something as good for students. Basically, there is no such thing as a tooth 'nerve', it is merely the middle gunky part, with bloods vessels and nerves, called the dental pulp. It is necessary for the tooth to form, and later keeps the inside of the tooth hydrated. Later in life it shrinks, and sometimes dies, which means a nasty root canal job. --Zeizmic 15:59, 1 November 2006 (UTC)

Years ago, when I still visited the dentist, I asked the lady cleaning my teeth whether, once grown, they are just static objects that don't change once they're fully grown. Not at all, she said -- they are very much living things. Teeth are only really hard on the outside, and they are well supplied with blood vessels and nerve endings. They also have repair mechanisms for taking care of minor scratches and so on. So it's not like dentists are absolutely mandatory -- healthy teeth are capable of mending themselves, just like everything else in our body. -- Chris 17:01, 1 November 2006 (UTC)

No dentists needed? Heh, well, I beg to differ. - Dozenist talk 03:09, 2 November 2006 (UTC)

Antisocial personality disorder

Can someone help me I would like to know who first came up with the term antisocial personality disorder and about ehn . Thank you.

Speaking of teeth...

What does that dream where your teeth start rotting out of your skull, cracking, splintering and crumbling away actually mean? I have that one fairly often. I remember reading somewhere that there is, psychologically-speaking, something very primal and deep-rooted (pardon the pun) behind it... --Kurt Shaped Box 16:37, 1 November 2006 (UTC)

I'm sure its just your subconscious trying to tell you that teeth are going to fall out if you keep doing the things you do. Teeth being your most permanent possessions, it's a vivid image that is going to have a lasting effect upon your waking hours. -- Chris 16:56, 1 November 2006 (UTC)

It is pretty much impossible to interpret symbols in dreams without context. Your mind is saying something to you; others can only guess at how your mind works, and not even that without getting to know your life situation pretty well first. (I'm feeling very Jungian today...) That being said, a quick googling should find some possible interpretations. In those google results, skip any sites that say "flying = travel, teeth = money, whatever = you'll meet a handsome stranger" :-) Weregerbil 17:25, 1 November 2006 (UTC)

I thought that certain dream themes were pretty much universal? The one where you're falling, or the one where you discover that a woman's vagina is lined with sharp teeth whilst having sex with her, etc. Has that all been discredited now? --Kurt Shaped Box 20:41, 1 November 2006 (UTC)

I have always been of the opinion that the teeth dream relates to self image concern, since losing teeth can be a permanently disfiguring experience. I have them from time to time despite taking good care of my teeth. --Jmeden2000 18:13, 1 November 2006 (UTC)

In my experience, people tend to overanalyze dream imagery. Why should teeth falling out represent anything more unusual than a latent fear of having your teeth fall out -- or at least a general level, death and decay? -- Chris 21:50, 1 November 2006 (UTC)

I just remember being told a long time ago that Freud said that dreaming of losing/damaging your own teeth was something psychologically significant. Just curious as to what it was supposed to be about. --Kurt Shaped Box 01:01, 2 November 2006 (UTC)

• I had that dream pretty regularly -- until I got all my teeth fixed about five years ago! Haven't had it since. I think it's one of those real obvious ones: it means you are worried about your teeth (or, as we refer to them, those "tiny time bombs in your head".) --jpgordon^∇∆∇∆ 00:50, November 2006 (UTC)

• What Dreams Actually Are

has been a topic everyone is always asking about, however I don't understand why people are not aware that medical science figured this out a long time ago. Which is to say, there is a factual explanation as to what dreams are, why they occur...the whole nine yards. It has been quite some time since I learned this in college, but I remember the general idea, which is as follows. When you are asleep, by no means does your brain "turn off". Sleep is an extremely complicated subject so I'm going to try and keep this simple (and brain functions are even more complex), but if you're really interested there is a lot of information on the internet that explains this. Sleep is for the purpose of resting your mind, not your brain. As a matter of fact, the brain can be even more active during REM sleep than when a person is awake. To explain dreams as simply as possible, this is basically what happens. Since the brain is still active during sleep, "thoughts" (not the best term but it's all I can think of) still occur, however because your cognition is resting, the thoughts are fleeting as well as in great quantity. Synapses are one of the major elements of the brains communication systems. For the purpose of simplicity, think of a synapse as one thing, whether it's in your life, your fantasies, or if it's a piece of furniture in your house (there are about one hundred trillion synapses in your brain). During conscious thought process they work together with the neurons and other parts of your brain. When you take away the consciousness variable, thought process is rather impaired. The thoughts are still there, but since they're not in use, the absence of the process part is where dreams come in: a random group of some of the billion thoughts in your head end up together. When you are awake, you select the particular thoughts and your mind fits them all together. But since the mind is not really in play, but the synapses are still firing all over the place, your brain does the best it can to have things make sense; i.e., your thoughts are linked together by whatever other thoughts your brain can use to piece everything together into a "story" of sorts. So the dream you had last night about riding the tea cups with your childhood pet at the Disneyland that happens to be in your living room as you and your deceased cat discuss the benefits of having your tires aligned DOESN'T ACTUALLY MEAN ANYTHING (keep in mind, to have that dream you have to have had a cat once, seen Disneyland, and have something with tires, otherwise those factors won't exist in your head). Since everyone has many dreams every night, on occasion you may remember one that it's totally outlandish. Further, it wasn't until recently humanity has learned about the brain, so for thousands of years people were forced to believe dreams met something. Add to that you have famous people like Freud who insisted dreams have meaning. You put all those influences together and everyone just gets brainwashed they mean something. Though everyone forgets the part about how Freud related everything to sex and was coked up every day. *** By the way, the dream about the teeth rotting/falling out that was discussed above was interpreted by Freud to mean castration due to guilt over masturbating. If none of this made sense, think of dreams as like "Mad-libs". Finally, I apologize if I misstated any facts or neglected something important, but I can't remember everything I learned in school! Therefore, you don't need to yell at me if I was wrong about something. However the gist IS correct. Even common sense can tell you that, since when have you had a dream interpreted for yourself right on? So, in conclusion, dreams do not have meaning. They are literally not much more than your unconscious imagination working randomly. Now you can tell your friends and family what dreams are, although they will likely insist that their dreams give the winning lottery numbers, and they just didn't get around to buying the ticket. SWEET DREAMS ALL!

Tomato Hornworm

I just found a hornworm that is about the thickness of my thumb and at least 10CM in length. I have never seen anything this large. It is unusual?

Our tomato hornworm article pointed me to this link: [3], which says they grow to about 4 inches long, which is about 10 cm. So, you have one on the large end of the normal size range. StuRat 18:59, 1 November 2006 (UTC)

Promiscuity

A bit OT but hopefully still of interest. This article was interesting http://www.iht.com/articles/ap/2006/11/01/europe/EU_MED_Sex_Study.php (I actually read it in my local paper but it's more or less the same). Of course (not having read the published journal paper however) this does appear to rely on people giving accurate reponses so it could be misleading. What was surprising to me tho is that the fact Western people are more promiscious then Africans was supposedly surprising to the researchers. I'd never really thought about it much but I have to say, this was what I personally would have expected. Although I'm aware of the high prevance of STDs I would have put this down to other issues like health care, the kind of promiscuity that's practiced, use of protection etc. And I would have expected that the more liberal and more modern Westernised world to have a higher promisicuity then the more conservative African world. Does anyone else feel the same? N.B. Let's not get in to arguments about whether promiscuity is good or bad and no racism please Nil Einne 17:58, 1 November 2006 (UTC)

I just loved the quote from this piece I heard today on the radio: "People are just as likely to be truthful about their sexual habits as they are about their income or their voting choices"... Is it me or does this mean "Lie like a rug"? --Jmeden2000 18:08, 1 November 2006 (UTC)

Agree with Jmeden2000. I'm certainly not going to accuse an entire continent of lying, but consider that vs 50 years ago, the stats for female masturbation have gone up from something like 50% to something like 95%. It's not because so many more women are masturbating, it's that so many more women are telling the truth. It's amazing how many people lie, even when the survey is completely confidential. Anchoress 18:16, 1 November 2006 (UTC)

I wondered whether the scientists were surprised about the result or only the journalists reporting about it. For the question of accuracy due to untruthful answers: Psychologists have some tricks to lessen the problem a bit: AFAIK, one usually includes a question that is somewhat embarassing and for wich it is known that most people should answer yes (I don't know what they usually use but I imagine it something like asking men whether have masturbated in the recent year.) Then, you use this to estimate how many people have answered truthfully. Simon A. 20:06, 1 November 2006 (UTC)

I'd be interested v/v the study to find out exactly what questions they asked, and of whom. Because there are so many languages in Africa, and things can be mistranslated in ways that may seem innocent, but may cause an unexpected result. Like the question, 'Are you unfaithful to your spouse' might be translated to, 'Do you sneak around on your spouse' and if s/he is NOT sneaking it might give a skewed answer. Or if the question is, 'Do you have intercourse outside marriage,' or 'Do you have intercourse,' wouldn't catch the people having just oral sex. I'm not trying to justify an opinion that Africans are more promiscuous than the study suggests, I'm just speculating. Anchoress 23:34, 1 November 2006 (UTC)

protein hydrolysis and H2S

I'm hydrolysizing big batches of protein and I'm concerned about the production of hydrogen sulfide, for my own safety. I'm testing acid, alkali, and protease hydrolysis. Are any of these methods more likely to produce significant H2S? (I presume the enzymatic method wouldn't produce any, unless there's bacterial growth). ike9898 18:09, 1 November 2006 (UTC)

shelf life and storage of dynamite and pyrotol

Hello...I am a novelist and in the book I am currently working on the 'bad guy' has wired a public place with dynamite. Question: pyrotol was available after WWI, would it still be viable in the early 60's if stored properly? If so, how would it have to be stored? If pyrotol would not be viable, would dynamite still be viable from that time period? Or would dynamite still be avialable in the 60's, if so, how would this need to be stored?...( I know that pyrotol would not be available in the 60's, as they discontinued use of this after the Bath School disaster of 1928). I would appreciate any and all help some one would care to give me...thanks very much, Sandy G.

Oncology Research

Is it possible to go into oncological research without an M.D.? As in, is there a Ph.D. program that will allow one to go into oncology research and still get to work with people/patients?

Thank you!

Maybe sorta if you went into Biomedical Engineering. BMEs often help in the clincal testing of new medical devices, but I think that their role in that case is primarily focused on the performance of the instrument, rather than the patient. ike9898 21:46, 1 November 2006 (UTC)

Also, I think that you could be involved in oncology research without an MD or PhD. As a nurse or lab tech, for example. Also, there are lots of PhD, non-MD scientist in cancer research, but I think these types are much more lab based than clinical (no patient contact). ike9898 21:49, 1 November 2006 (UTC)

Image:Lugano.jpeg

As stated, the image was made between 1905 and 1915. Was it shot in color like several World War I photos or colorized much later? --Brand спойт 19:57, 1 November 2006 (UTC)

Since it was shot by Sergei Mikhailovich Prokudin-Gorskii who pioneered color photography I assume it was shot in color. - Dammit 19:59, 1 November 2006 (UTC)

To clarify, his technique was to take 3 black and white photos of each scene, each with a different color filter (red, green, or blue). His idea was to use a projector to recombine them into a color projection. With modern technology, however, we can combine the three images into an excellent full color image. The only color distortions are when something moved between the three frames. StuRat 20:06, 1 November 2006 (UTC)

Ehrm, the link. —Bromskloss 20:51, 1 November 2006 (UTC)

What is it good for?

"Many waterfowl and some other birds, such as the ostrich and turkey, do possess a phallus. Except [sic] during copulation, it is hidden within the proctodeum compartment within the cloaca, just inside the vent." Vitriol 20:17, 1 November 2006 (UTC)

Sexual intercourse --Russoc4 20:30, 1 November 2006 (UTC)

Does "during copulation, it is hidden within the proctodeum compartment within the cloaca, just inside the vent" mean anything to you? Vitriol 20:34, 1 November 2006 (UTC)

"Except during copulation". I have personally seen a duck's penis FWIW. --Kurt Shaped Box 20:44, 1 November 2006 (UTC)

Close as I can figure, there are no errors in the original source. Why the [sic]? It certainly shouldn't read 'accept during copulation'. -- Chris 21:45, 1 November 2006 (UTC)

I accept that. Vespine 22:02, 1 November 2006 (UTC)

Sorry, I got confused because I thought it was saying they possess a phallus, except during copulation it's hidden. I'll go edit that to prevent fuckups like mine. Vitriol 22:05, 1 November 2006 (UTC)

I see how you misread that. Just change two punctuation marks: ...[they] do possess a phallus except during copulation. It is hidden within the cloaca... Hyenaste ^(tell) 01:38, 2 November 2006 (UTC)

Plane crash

A few days ago, in a question now already moved to the archives, Keria wrote:

Which seats in a big airliner do you think are safer depending on the different types of crashes? It does happen quite often that a plane crashes and it is announced that "189 people died, and 3 survived" or sentences of that sort they never specify where the lucky ones were sitting. I was thinking more towards the tail of the plane, dont know why, it seems stronger somewhat but then that last Kentucky one only the co-pilote got dragged out of the burning plane by the fire brigade if I remember correctly. Any thoughts or statistics? Thank you.

This subject is being covered on the U.S. TV show ABC News Nightline tonight (11:35 pm for Eastern Time viewers), and there is an an online article here on their web site. In summary, the article says that preparedness is more likely to matter than where you sit, but that there is a small advantage to having an aisle seat and, of course, to being relatively near an exit.

--Anonymous, 21:20 UTC, November 1, 2006.

And it happened again last week in Nigeria 96 death and 9 survivors in a 737 crash. Survivors believe God/Allah gave them a hand and they don't seem to have a clue about much.

"I don't know exactly what happened after the plane crashed - we were shouting for help and still praying."

Then some farmers nearby rushed to their rescue undoing their seatbelts to drag them from the wreckage.

from http://news.bbc.co.uk/2/hi/africa/6102618.stm

Keria 09:59, 2 November 2006 (UTC)

The back of the plane typically suffers the least amount of damage on impact. That's where they keep the black box in the bigger planes. I'm not sure if that translates into passenger safety, but it is likely. ---J.S (t|c) 00:35, 4 November 2006 (UTC)

According to The Worst Case Scenario Handbook: Travel Edition, the back of the plane, is indeed, safest. This request to relatives booking flights has resulted in my seat being so far back I don't have a window, and can watch the flight attendants make coffee. Russia Moore 04:51, 8 November 2006 (UTC)

"Psychoelectronic" devices and weapons?

I'm sure that anyone that's been around the net for a while (especially Usenet) will have come across people who believe that they are the victims of "psychoelectronic" attacks - be it from the CIA, MI5, the Elders of Zion, Freemasons, Illuminati, Knights Templar, Scientologists, or whichever group it is that they happen to have issues with. They often speak of devices capable of forcibly reading data from the human brain (a mind probe, if you will), causing great pain and long-lasting side effects to the victim - or technology capable of writing data to the brain (false memories, loud electronic screeches designed to drive the subject insane, etc.). These 'psychoelectronic weapons' are often mounted on satelites but apparently can be used at ground level too, over shorter ranges. The supposed victims of pschoelectronic warfare actually do sometimes sleep in aluminium foil hats or line the walls of their bedrooms (the technology supposedly works better on the sleeping) with thick aluminium/lead plate in order to deflect the waves/rays/beam/whatever. Sometimes, they claim that they are unwilling guinea pigs in the testing of new military technology and that soon it will be possible for the 'mind control satelites' to routinely record everyone's dreams, which will be then kept on file for future use against the subject.

So, my question is thus: Is there actually any theoretical basis to any of this stuff, or is it just sci-fi that certain mentally-ill people have been taken in by because it seems to fit in with the symptoms of their illness?

I wouldn't even know where to start looking for this on WP. Thanks. --Kurt Shaped Box 21:25, 1 November 2006 (UTC)

How about here? Seriously, an understanding of how the mind works is barely in its infancy. These people need to go back on their medications. Clarityfiend 21:45, 1 November 2006 (UTC)

We don't have the technology read people's thoughts with a captive subject, with a "thought reading helmet", let alone from a satellite… If that capability existed don't you suppose we would have heard of it by now with places like Guantanamo? I bet they'd love to be able to do it. Current technology is collectively known as Neuroimaging. As to the indiscriminate beaming out of some kind of waves that can slowly drive people crazy or stupid, that doesn't sound quite as far fetched. I have heard theories that certain types of radiation can affect mood, but I've not come across any real case scenarios. Either way, I don't believe something like this could exist in such secrecy. And the fact that people have been claiming this at least since the cold war, 'the commies were doing it', leads me to lean towards just a classic conspiracy theory. Vespine 21:54, 1 November 2006 (UTC)

Just had a brainwave (heh!). I remember reading something along those lines and now I've found it. Sonic_weaponry#Designed_to_emit_sound_as_an_irritant - I suppose that it's theoretically possible (but very unlikely) that some of these people have had infrasonic weapons used against them (I guess that the security services might have an interest in subtly driving certain 'subversive' individuals insane). --Kurt Shaped Box 22:22, 1 November 2006 (UTC)

Try telling those guys that. The standard response is usually along the lines of "'They' are using their psychoelectronic devices to purposefully manifest symptoms of a mental illness in me in order to discredit me because I got too close to the truth. One day you will understand too.". It's absolutely impossible to reason with them. --Kurt Shaped Box 22:15, 1 November 2006 (UTC)

An interesting theory on what is going on there is Susan Blackmore's idea that the phenomen of sleep paralysis might be responsible for accounts of people who feel controlled by outside powers. She was thinking of medieval accounts of succubi and incubi, and modern talk on abduction by aliens. Maybe this is the same here. Or, we are just talking about good old paranoia and schizophrenia. Taking into account that shizophrenia is a rather common desease, you should not be surprised to meet many of these people on the net -- and not all are aware that they are ill. Simon A. 21:56, 1 November 2006 (UTC)

Tinfoil hat seems like a reasonable place to start, though most of the links there to viable scientific topics aren't likely to contain info about the pseudoscientific applications - you most likely will have to read some of the external links for that. I'm assuming "psychoelectric" means manipulation via EM radiation.

Note that scientists can "read people's thoughts", to a very limited and crude extent, in a laboratory setting. For example, a test subject given a radioactive tracer glucose solution to drink and then monitored on a PET scan device, can then be shown photos of strangers and loved ones. Different areas of the brain will "light up" depending on their reactions to the photos, enabling the scientists to have a rough idea of what each subject is thinking. StuRat 03:57, 2 November 2006 (UTC)

In 1946, an alien ship was stripped at Area 51, revealing an organic conductor with interesting magnetic properties. In 1951 DuPont started manufacturing pillows containing TMS devices that allow the NSA to take control of you brain and make you vote for Ralph Nader. --JWSchmidt 14:00, 2 November 2006 (UTC)

Tickling

Why did we evolve the ability to be tickled?

I fancy it was to protect vulnerable parts--Light current 21:52, 1 November 2006 (UTC)

Isn't that what pain is for? Under the arms I'd believe, but sole of your feet? How is that more vulnerable then a lot of other places that aren't typically ticklish? I'd be more likely to think it's a by-product of a certain level of skin sensitivity, not necessarily a separately evolved ability, so to speak. Vespine 21:59, 1 November 2006 (UTC)

If you dont believe the sole of the foot thing, get a sharp knife and draw the blade along the sole of your foot from heel to toe (or the other way if you prefer) and then youll see what I mean. The skin there is very soft.--Light current 23:59, 1 November 2006 (UTC)

For those who wear shoes all the time. Those who never do (or did, like pretty much all of our ancestors) will have a thick layer of callus. It will actually be the thickest 'skin' of the body. DirkvdM 13:41, 2 November 2006 (UTC)

Our article on tickling mentions some hypotheses. Simon A. 22:03, 1 November 2006 (UTC)

So we'll know when we have spiders or centipedes crawling on our bodies? That 'tickling of tiny legs' feeling is one of the most uncomfortable, disconcerting sensations of all for me, even if it turns out to be a 'false positive'... --Kurt Shaped Box 22:30, 1 November 2006 (UTC)

I would think the enjoyable sensation of being tickled by a loved one serves a social purpose. Note that it's difficult to be tickled by a stranger, showing the "ticklish" reaction involves complex social interactions, not just a raw sensation. Also note that the person doing the tickling is almost always dominant (as a parent) and the one being tickled is submissive (as a child). Thus, it may serve a very subtle purpose of reinforcing power relationships, without resorting to violence, to establish dominance. StuRat 03:46, 2 November 2006 (UTC)

Dizziness during inflation

When inflating something with my lungs (an innertube, an air mattress...), after a while I start to feel a bit lightheaded. Why is this? Does it have to do with the increased amount I'm breathing in and out (essentially I am hyperventilating), or is there a different reason? — QuantumEleven 22:06, 1 November 2006 (UTC)

Rapidly increasing and decreasing blood pressure, so something along the lines of orthostatic hypotension? Thats if it is similar to the 'headrush' experienced when standing after having remained in a relaxed state for a while. Philc _T^E_C^I 23:03, 1 November 2006 (UTC)

Often people Valsalva when they blow up an innertube. Increasing the pressure in your chest decreases your blood return to your heart and lungs, causing decreased delivery to your brain and the feeling of dizziness. InvictaHOG 23:19, 1 November 2006 (UTC)

I think it is simply hyperventilation.  --Lambiam^Talk 02:28, 2 November 2006 (UTC)

You're not hyperventilating when you are blowing up something! You might be taking larger tidal volumes, but your minute ventilation will drop because your respiratory rate drops. InvictaHOG 11:34, 2 November 2006 (UTC)

Have to agree with the hyperventilation hypothesis. Minute ventilation is the product of respiratory rate and tidal volume. The vital capacity used to blow up an innertube might be 2.5-3 litres, i.e. five to six times "tidal volume", to maintain your "normal" minute ventilation you would have to take only 2-3 breaths per minute, which is unlikely as you are trying to blow up this darned inner tube as fast as possible. Hence, hyperventilation and a drop in PaCO2. Mmoneypenny 18:45, 2 November 2006 (UTC)

Thanks to everyone who replied - quite a few interesting links there for me to peruse! :) — QuantumEleven 07:42, 3 November 2006 (UTC)

Phobia of centipedes and millipedes - and why?

Is there a name for this? I have it.

Insects don't bother me at all. Arachnids only bother me if they're close to/on me and I'm taken by surprise. Centipedes and millipedes make me flee in terror at the very sight of them. I can't even kill them because that would mean having to approach them. Certainly seems that for me, more legs = more danger. Why do I have this? I don't remember something terrible happening to me as a child with these foul beasts to trigger it off - I've always hated (yes, it is complete and utter hatred - they disgust me and I would destroy their entire kind if it was in my power) them as far back as I can remember. --Kurt Shaped Box 22:41, 1 November 2006 (UTC)

Entomophobia includes various classes of bugs such as arthropods, which is what Myriapoda are, so that might cover you. Er, I mean that might describe your situation. DMacks 23:35, 1 November 2006 (UTC)

Myriapodaphobia? That sounds like it could be right. Well, there's a Google hit for it anyway. Doesn't look like there's any support groups though... :( --Kurt Shaped Box 23:41, 1 November 2006 (UTC)

You shold force yourself to get over it. It isn't good to have that much of a hatred for a, basically, defenceless animal which does, basically, no harm to humans. They can bite, but pain always goes away, they are not like spiders, of which some species can kill you. Next time you see one, wear gloves, and pick it up. It will probably try to walk onto your arm, at which stage you change hands. If you can stay calm, you should get over the phobia. I was always afraid of them, but I find watching them, and the synchornisation of their legs, really fascinating.

As for the why are you scared of them, it might be a snake things. Their movement looks much like a snake, and we are hardwired to be scared of snakes. --liquidGhoul 01:24, 2 November 2006 (UTC)

Yeah, I know it's not healthy to hate something that much. If, for example I hated Jews as much as I hate centipedes, history would remember me as *worse* than Hitler. It's like I have some sort of mental barrier in place that stops me from accepting centipedes as part of my world. I have nightmares about centipedes all the time and every time I wake up from one, I have the urge to destroy every single last one of them, yet I'm still too scared to go near them, which makes me hate them even more. If I had a gun and I saw a centipede, I would shoot it dead and feel good afterwards. No doubt about it. Heh, that sounds so messed up now I've typed it out. --Kurt Shaped Box 01:36, 2 November 2006 (UTC)

They creep me out, too. I think it's either how fast they move or all those wiggling legs that makes them creepy. I notice I'm scared by any insect quicker than me, as that means it can crawl on me before I can stop it. On the other hand, slow moving or still insects don't bug me much at all. :-) StuRat 03:17, 2 November 2006 (UTC)

Kurt Shaped Box has a phobia. He need hardly equate that with racism and mass murder. The obvious thing to do is to avoid the object of your hatred/fear. The only real problem is whether he is now obsessing about the phobia. If he can't refrain from doing so, then he could use the services of a trained mental health professional.

It is not the dislike of these creatures that is the issue, but the nightmares. It's perfectly okay for Kurt Shaped Box to have the hatred as long as he isn't constantly thinking about it.

B00P 08:12, 2 November 2006 (UTC)

I disagree. If you have such a hatred for something, to the point where you want to wipe it off the earth, you are bound to unwillingly pass that on to others. Centipedes and millipedes play an important role in most ecosystems. I'm sure Kurt won't willingly do anything to cause the extinction of any species of an animal. But it sounds as if he would if he had the technology. We need to encourage and teach others to value biodiversity, and attitudes like this don't help. I don't mean any offence, but talking about extinctifying (I made that up, I'm tired) a huge number of species because of ignorance, when there are so many people in the world working really hard to do the conserve them through intentions which are purely for the benefit of them or human kind, pisses me off a bit. Even if it is in good humour. --liquidGhoul 13:38, 2 November 2006 (UTC)

I don't consider a fear to rise to the level of a phobia unless it interferes with his life in a significant way. As there is very little benefit to allowing centipedes and millipedes to crawl on you, avoiding this is not really a problem. StuRat 18:45, 2 November 2006 (UTC)

Aw, c'mon. liquidGhoul is going over the edge. Kurt Shaped Box is hardly in a position to be wiping out whole ecosystems. And the notion that he will infect the world with his hatred is also quite wrong. My mother had a horror of rodents which she did not pass on to anyone else. I detect a whiff of "Political Correctness" with the insistance that everyone must accept and love everything (with the exception that it's okay to reject anyone who doesn't). Additionally, there is a huge difference between what one thinks and what one does. The danger in the idea that they are the same leads to the belief that once having thought of something, one is already "soiled." And if that's the case, it isn't actually worse to act out on one's negative ideas. Well, that's wrong. Our thoughts come unbidden; it's what we do with them that counts. In the case at hand, the only question id how much they are tormenting Kurt Shaped Box. If they're interferring with his life, then he should get help. Otherwise, it's just a quirk. B00P 23:48, 2 November 2006 (UTC)

Before this gets out of hand, guys - I would just like to inform you all that I was slightly tired and emotional last night. Perhaps the 'Jew' analogy and suggestions of legitimized centipede genocide were slightly ill-advised when perhaps a single line stating "Centipedes really scare me" would have been sufficient. --Kurt Shaped Box 00:10, 3 November 2006 (UTC)

Antisocial Personality Disorder Origon

Do not double post and be patient. You asked this same question all of 8 hours and 5 minutes before asking it again. Have you looked at your original post, where Light current has provided a helpful link (in the question)? That's likely to be all the information we have on the subject. --Tardis 00:01, 2 November 2006 (UTC)

Proton

Could you explain to me which would be the more valued result, removing one proton from each nucleus of a sample of gold or adding one proton to each gold nucleus?

The number of protons in the nucleus of an atom of a given element is called the atomic number. Here you will find List of elements by atomic number helpful. Melchoir 23:42, 1 November 2006 (UTC)

To 64.12.116.74, who asked this homework question and the one immediately following:

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.. --Tardis 23:55, 1 November 2006 (UTC)

Well, since removing a proton would produce platinum (at a value of £108/g for 99.995% pure), and adding a proton would produce mercury (which goes for around £70/kg at the same purity), I'd say the more valued result would be removing a proton. GeeJo ^(t)⁄_(c) • 23:44, 1 November 2006 (UTC)

This question could be more complex than we assume, if the number of neutrons is also considered. Thus, if we remove or add a proton from/to an isotope of gold, and leave the number of neutrons constant, will it produce stable mercury or platinum, or will it decay ? If so, how quickly will it decay, what will be the decay products, and what are their values ? StuRat 03:04, 2 November 2006 (UTC)

I took a look, and it appears that the only stable isotope of gold, AU-197, would be changed into either PT-196 or HG-198, both of which are also stable. StuRat 03:11, 2 November 2006 (UTC)

(edit conflict) Even before that, what might be the value of a source of those unstable isotopes? If it's just a thought experiment, may as well include in it a physicist being offered a coupla grad students or other cheap labor to do it on a useful scale on demand. DMacks 03:14, 2 November 2006 (UTC)

As long as we're running with the question, the prices should be adjusted by the price of the nuclear binding energy. And, for bonus precision, the price of protons. Melchoir 16:17, 2 November 2006 (UTC)

Periodic table

Why are the atomic masses listed in the periodic table not whole numbers?

Try the first few paragraphs of Atomic mass. Melchoir 23:40, 1 November 2006 (UTC)

Namely the first sentence of the second paragraph (it's an average of all the Isotopes of that element). Martinp23 23:56, 1 November 2006 (UTC)

It's not an average, it is proportional to the isotopes found on Earth, e.g. if there are two isotopes, 50% of which are on isotope, then the AM would be exactly between them the AM of both the isotopes. --liquidGhoul 01:18, 2 November 2006 (UTC)

Yes, a more correct term would be weighted average.

But the occurrence of different isostopes isn't the only reason why atomic masses (or atomic weights as we used to say) are not whole numbers. There are some elements where only one isotope occurs in nature and yet they still have non-integer atomic masses. For example, beryllium is all beryllium-9, but its atomic mass is 9.012+, not 9.000. Carbon-12 is the only isotope whose atomic mass is an exact integer (12.000) and that's because the atomic mass unit is defined in terms of carbon-12.

There are two reasons for this small variation between isotopes. One is that they have a different ratio of protons (which are a bit lighter) to neutrons; beryllium-9 has 4 protons and 5 neutrons while carbon-12 has 6 of each, so naturally beryllium-9 should have an atomic mass a bit greater than 9. But there's a second reason, which is that different isotopes or elements have different amounts of binding energy. which is expressed as mass (see mass-energy equivalence, which is to say, E = mc² and all that).

This last effect, known as the "mass defect" or "packing fraction", is what makes nuclear reactions an energy source. If you could make a fusion reactor that would convert beryllium into carbon (not a practical proposition, but these are the elements I used as my example, so let's stay with it), then the excess mass in the beryllium atoms would provide the energy released. Again, see binding energy for more.

It is sometimes useful to refer to an isotope by as a simple whole number, a count of protons and neutrons; that's what we're doing when we say beryllium-9 or carbon-12. But the term for this is mass number, not atomic mass. And it only applies to specific isotopes, whereas an element consists of a mixture of isotopes.

--Anonymous, 01:20 UTC, November 2.

Squeezing legs

Why is it, if one sqeezes someones leg just above the knee with ones hand, it makes them feel uncomfortable (not ticklish exactly), whereas, if one squeezes ones own leg in a similar manner, it is quite bearable. Is this the same thing as ticklishism?--Light current 23:53, 1 November 2006 (UTC)

Sounds like part of social conditioning in western culture... anything above the knee and on the inside tends to be "off limits" in a "show me where he touched you billy" kind of way.

Then again, expected sensation and self-inflicted sensation is usually more bearable then the surprise kind... ---J.S (t|c) 00:47, 4 November 2006 (UTC)