Wikipedia:Reference desk/Archives/Science/2008 June 5

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June 5

What is the latest scientific understanding of the relationship between dietary cholesterol & coronary heart disease?

The following is an excerpt from this article: [1]

[T]he maximum intake value for cholesterol of 300 mg ... was initially developed in 1968 by the American Heart Association for patients with high blood cholesterol .... Recent reviews of the scientific literature by U.S. authoritative bodies led such groups to conclude that "the relationship between cholesterol intake and LDL-cholesterol concentrations is direct and progressive, increasing the risk of coronary heart disease" and that cholesterol intake should be kept as low as possible within a nutritionally adequate diet.

To date, other countries viewing the same evidence as the U.S. come to the conclusion that the cholesterol in food is not the main influence on blood cholesterol ...

It seems that health authorities in different countries had access to the same evidence but came to very different conclusions about the significance of (high) dietary cholesterol intake as a CHD risk factor.

Could someone versed in the subject shed some light on what the best empirical evidence is telling us about dietary cholesterol & CHD? —Preceding unsigned comment added by 71.175.22.134 (talk) 02:29, 5 June 2008 (UTC)

CHD and coronary artery disease both require a multitude of factors that contribute to their development - it's difficult to talk about one single element, in this case, cholesterol. Yes, high LDL and low HDL show high risk, but now it's understood that such vascular diseases have oxidative stress and inflammatory components to them. Wisdom89 _{(T / ^C)} 05:33, 5 June 2008 (UTC)

On balance, it can be seen that the cholesterol theory of CAD causation has its limitations. First, the liver--as part of normal metabolism--produces cholesterol, quite apart from dietary sources. Second, cholesterol far from being a "villain," is absolutely essential for hormone production and nerve transmission. Third, the evidence is that lipid deposition only occurs after coronary vessel damage from such factors as hypertension and free radicals. Fourth, the concept of simple deposition of fatty substances upon the vessel wall--from blood flow--is flawed. Such deposits occur on the sub-intimal layer, not the surface immediately facing the lumen of the vessel. Fifth, studies exist demonstrating just as high correlation between dietary factors such as high levels of simple carbohydrates (e.g., sucrose), as with cholesterol and lipids. The wise clinician would counsel his/her patients AGAINST dietary extremes, such as excess intake of cholesterol, fat, and refined sugar, and FOR exercise and supplements which might assist with neutralizing free radicals. He/she would also be particularly alert to the risk of CAD in his/her hypertensive patients. Drnovlamas2 (talk) 14:57, 5 June 2008 (UTC) (Dr. T.C.H.)

yeah, it's pretty complex. not only is cholesterol so necessary we produce it, studies where cholesterol is driven way down below 100 show a rise in death rate, from things like accident, homicide, suicide, etc. It may be just coincidence, but it's persistent enough to make you wonder how sensitive function of the brain, whose cell membranes are stabilized in part by cholesterol, might be to the level. and as a kicker, blood levels of cholesterol might be more sensitive to intake of saturated fat than to intake of cholesterol itself. which ties in to the recent failures of efforts to reduce blood cholesterol by interfering with its takeup from the digestive tract by flooding it with large quantities of plant sterols, which sounds like it would work if straight dietary intake of cholesterol were an important factor. and, of course, now we don't look at total cholesterol as so important any more, we have divided it into LDL, "bad", and HDL, "good"; there might well be further subdivisions we haven't identified yet. and as the guy said, the mechanism isn't just like clogging your kitchen drain with fat, it's an active inflammatory process involving some sort of injury to the arterial wall getting scarred up with cholesterol somehow involved in producing big obtrusive scars, with the assistance of white blood cells and so on. which throws the whole thing into the now hugely important category of immune system disorders which appears to cover everything from diabetes to cancer to arthritis. Gzuckier (talk) 15:17, 5 June 2008 (UTC)

Unknown Equation

What is the name of this equation and what is its significance? What does it mean? $\langle \Omega |{\mathcal {T}}\{{\hat {\phi }}(x_{1})\cdots {\hat {\phi }}(x_{n})\}|\Omega \rangle ={\frac {\int {\mathcal {D}}\phi \phi (x_{1})\cdots \phi (x_{n})e^{i\int d^{4}x\left({1 \over 2}\partial ^{\mu }\phi \partial _{\mu }\phi -{m^{2} \over 2}\phi ^{2}-{\lambda \over 4!}\phi ^{4}\right)}}{\int {\mathcal {D}}\phi e^{i\int d^{4}x\left({1 \over 2}\partial ^{\mu }\phi \partial _{\mu }\phi -{m^{2} \over 2}\phi ^{2}-{\lambda \over 4!}\phi ^{4}\right)}}}$ Ζρς ι'β' ^¡hábleme! 05:15, 5 June 2008 (UTC)

I think it means, "I really wanted to show off when I was writing this equation". Or maybe, "Nah, nah, my brain is bigger than yours!" « Aaron Rotenberg « Talk « 06:23, 5 June 2008 (UTC)

Holy shit, is that an integral inside an exponent inside an integral???? Someguy1221 (talk) 06:44, 5 June 2008 (UTC)

Looks like it. As far as I can see this really looks like a meaningless, complicated equation created for the sake of it - though i'd be fascinated as to what it is if that isn't the case. ~ mazca ^talk 08:18, 5 June 2008 (UTC)

this looks like it is coming from conformal field theory or (quantum) statistical physics. Oded (talk) 09:56, 5 June 2008 (UTC)

Well, shows what I know. :) failed all the quantum theory modules on his chemistry degree ---> ~ mazca ^talk 12:41, 5 June 2008 (UTC)

I don't know where it comes from (though something to do with quantum mechanics seems a safe bet), but this looks more like just a definition: the left-hand side is in Dirac bra-ket notation, and I'd guess the right-hand side to be just the same thing written out in more verbose notation. Also, the denominator on the right-hand side seems to be just a normalization factor. What context did you encounter it in, anyway? —Ilmari Karonen (talk) 10:39, 5 June 2008 (UTC)

Well, I came across this equation in Uncyclopedia. However, I believe it is a legitimate equation because I saw exactly the same equation on some YouTube video (most likely about quantum mechanics or calculus). I saw that video when I hadn't yet edited Wikipedia, but had wanted to post a question about it when I started (I just couldn't recall it verbatum). I am pretty sure it is a quantum mechanics equation due to the context of the first time I encountered it, and the bra-ket notation. Also, φ and ψ are used quite a bit in quantum mechanics (I'm pretty sure), and quantum mechanics is known for its confusing equations, ideas, and such. Ζρς ι'β' ^¡hábleme! 11:42, 5 June 2008 (UTC)

I'm pretty sure this is an equation from quantum field theory. And believe it or not, it is an abbreviated form - the D function in the integrals is a shorter way to write another function. I'm pretty sure the entire equation is the Green's function. PhySusie (talk) 12:17, 5 June 2008 (UTC)

Looked it up. I thought it looked familiar. The notation is similar to that in "Introduction to Quantum Field Theory" by Peskin and Schroeder. This equation is used in perturbation theory for interacting fields. PhySusie (talk) 12:34, 5 June 2008 (UTC)

A difficult quantum field theory equation whose source is personal memory via Youtube via Uncyclopedia turns out to be genuine? I am stunned, I don't know what to say. Criticising someone for not using WP:RS is looking like a very shaky thing to do from now on. SpinningSpark 13:17, 5 June 2008 (UTC)

Well, I saw it on YouTube first a while back and then Uncyclopedia last night (I thought it would be funny to see how they spoofed QM). I figured two exact, independent reproductions of the same very complicated formula could not be coincidental. Wait, was that sarcasm? Ζρς ι'β' ^¡hábleme! 14:18, 5 June 2008 (UTC)

Did it occur to you that maybe the video stole the equation from the uncyclopedia? --Shaggorama (talk) 15:28, 7 June 2008 (UTC)

Bodybuilders

What is it that gives bodybuilders such leathery skin? —Angr 05:36, 5 June 2008 (UTC)

Shave off the body hair and apply tan colour and oil. Graeme Bartlett (talk) 12:04, 5 June 2008 (UTC)

You think that's all? The leathery skin seems so universal, I figured it was something like building all that muscle mass increased blood flow to the skin which in turns hardens and reddens the skin and so on. —Angr 16:06, 5 June 2008 (UTC)

Nah. It's just buckets of fake-tan. For increasing visible "definition". Have a look here and compare the pictures of Jay Cutler. He looks normal in the training pictures, then in the posing/in competition pictures he looks like he's made of mahogany. Fribbler (talk) 16:27, 5 June 2008 (UTC)

When bodybuilders are ready for competition they have very low BMI, which is one of numerous reasons bodybuilders have a distinct look compared to the Strongman_(strength_athlete) or Weightlifter. Bodybuilders don't have some inherent leathery skin, but years ago I had a mate I worked out with called Eddy Ellwood (see him here if you're interested [2]) who was one of the top guys around, when he was really cut I swear you could see the muscle fibres! Low BMI and increased vascularity changes the appearance of the skin to look 'leathery' but, as has been pointed out above, the oil and tan are more major factors. 87.112.89.101 (talk) 02:48, 6 June 2008 (UTC)

You can – across his pecs when he gets more into frontal transformer-type positions. Julia Rossi (talk) 04:11, 6 June 2008 (UTC)

research resources for the history of the discovery of anaerobism in bacteria

I need some quick resources that outline how our current information of anaerobism developed -- currently I only have information on who first discovered glycolysis which IMO would be quite after the realisation that bacteria could develop in anaerobic conditions. Also, was the distinction between prokaryotes and eukaryotes clear before the discovery of glycolysis and the other chemical processes involved in fermentation? Also how did our knowledge of the distinction of facultative and obligate anaerobes (as well as aerotolerant species, microaerophiles, etc.) develop? John Riemann Soong (talk) 07:59, 5 June 2008 (UTC)

This kind of history of science research is very tricky, and usually requires physical access to specialized libraries and archives. en.wikipedia has an article on history of biology, but none yet on history of bacteriology. You might find the article historiography of science helpful in thinking about how to approach your problem, although it has nothing directly relevant in it. What you really need is the email address of a helpful librarian at an appropriate medical or university library at a facility where some of the research you're talking about was actually done, years ago. HTH. --arkuat (talk) 07:36, 9 June 2008 (UTC)

Asteroid

If we find a large asteroid heading for the earth, do we have the technology to make a gravitational tractor to save us? Bastard Soap (talk) 14:46, 5 June 2008 (UTC)

The article gravitational tractor mentions that a couple of guys have called it feasible. But, these guys are not exactly rocket scientists.. oh, wait. Friday (talk) 14:50, 5 June 2008 (UTC)

The largest unstated variable here is the amount of time. If you've got one year, no way. If you've got 25, perhaps. If you've got 50, almost assuredly. Note in particular that a grav tractor is slow-acting. Additionally, the mass of the asteroid is a concern -- the larger the asteroid, the less effective a grav tractor will be (and note also that for a sufficiently small asteroid, a Project Orion-style nuclear propulsion solution may be both faster and more easily accomplished). — Lomn 14:55, 5 June 2008 (UTC)

It would be unlikely for us to spot a planet smasher with 25-50 years notice. The percentage of the sky studied is very small. The financial allotment to such things just isn't enough to accurately forecast impact events. The Comet Shoemaker-Levy 9 was only spotted a few months before it impacted Jupiter. ScienceApe (talk) 18:57, 5 June 2008 (UTC)

That depends on the nature of the asteroid. Per our article on asteroid deflection, attention was recently paid to a potential 2029 encounter (21 years out). While that's been ruled out, orbital deflections raise the possibility of a 2036 encounter (28 years out). Further, (29075) 1950 DA is the solar system body with the highest presently known probability of impacting Earth, in 2880. Comets falling from the Oort Cloud and beyond -- no, we won't likely have 50 years' warning. Asteroids in the inner solar system? Utterly plausible. — Lomn 20:29, 5 June 2008 (UTC)

If it's soon, nuke it. If it's a while, paint one side white. Doable, WilyD 19:02, 5 June 2008 (UTC)

Painting one side white is my favourite solution - it has a certain elegance to it. Blowing things up is all well and good, but giving it a makeover has serious class. I'm not sure it's always an option, though - I believe it depends on the rotation of the body. --Tango (talk) 21:51, 5 June 2008 (UTC)

Shouldn't we also paint the other side black? -SandyJax (talk) 21:50, 5 June 2008 (UTC)

No need, a typical asteroid is pretty dark anyway (3-10% of light reflected), and most of the rest are still fairly dark (10-22%). --Tango (talk) 21:56, 5 June 2008 (UTC)

How does painting one side white help? Do only absorbed photons transfer momentum? Also how would you give it a make over exactly? Bastard Soap (talk) 07:37, 6 June 2008 (UTC)

Reflected photons transfer more momentum that aborbed photons - a perfectly reflective surface experiences twice the radiation pressure of a black body. The theory is the same as the principle of the solar sail; implementation details can be left to the engineers. However, the pressures involved are very smnall - about 10^-5 Pa at 1 AU from the sun according to this article. So, by my reckoning, radiation pressure on an asteroid with linear dimensions of the order of 1 km would generate an acceleration of around 10^-8 ms^-2, which would take years to significantly affect the asteroid's course. Also, the acceleration decreases in inverse proportion to the dimensions of the asteroid (because mass increases as the cube of the linear dimensions, but surface area only increases as the square) so the bigger the asteroid the less effective this method becomes. Gandalf61 (talk) 10:44, 6 June 2008 (UTC)

A large solar sail, robotically managed, could be tethered to an asteroid to provide far greater acceleration than merely painting one side white. If the asteroid is lose or crumbly, put a net around it and tether the sail to the net. An ion engine could be tethered to the asteroid instead, to provide small thrust over a long period. It does not take musc force to cause a miss years in the future. Bag it, move it, watch it sail by. Sayonara. Edison (talk) 13:54, 6 June 2008 (UTC)

I think the issue is in the definition of "significantly affect the asteroid's course". A very small change in course at one point in time can result in a very large chance of course years in the future, especially if the asteroid is going to pass close to another massive body (for example, the asteroid that's going to pass close to Earth in 2029 and then again in 2036 - a very slight change in its course before 2029 could result in a massive change in position by 2036, that's why we can't get a precise estimate of where it will be in 2036 until after the 2029 encounter, the slight errors get vastly magnified). --Tango (talk) 14:20, 6 June 2008 (UTC)

Yarkovsky effect WilyD 14:25, 6 June 2008 (UTC)

... which has shifted the trajectory of asteroid 6489 Golevka by only 15 km over the course of 12 years. I rest my case. Gandalf61 (talk) 15:05, 6 June 2008 (UTC)

Which is why if we don't have much time, we bust out the nukes. See my original comment - but also note that for a half black, half white asteroid, Yarkovsky is supercharged compared to the average colour difference across asteroids. If you have 50 or 100 years, it should work well. WilyD 15:13, 6 June 2008 (UTC)

If you do it far enough in advance, 15km could be plenty. --Tango (talk) 15:38, 6 June 2008 (UTC)

How exactly do you paint one side white? You send some paint bombs or something? Also how is it that reflected photons transfer more energy? And do reflected photons decrease in wavelength afterwards? Bastard Soap (talk) 19:15, 7 June 2008 (UTC)

Celluar Biology

Is it true that some part of the blood is a watery fluid, and floating in it is fluid are round particles. Is blood formed in globules with little color, but looking reddish? Where is the oxygen stored in the red blood cells? Are all the blood cells the same shape in humans, is there a difference between animal blood cells and human blood cells, is it true that human red blood cells have a nucleus? What is a cell nucleus, I don’t understand what they are. What is the structure of the cell’s nucleus? What is the hard, clear part near the front of the eye that looks like a piece of glass or crystal? How many nerves does a muscle have in it . why do the muscle in a cow have a striped look, that look like rings and wrinkles, but why to the fiberd How come when you scrape off a bit of chalk, breaking the chalk particles apart, how come they aren’t white at all, they are clear or transparent, like glass, but when they are together, how can they add up to white. What cells does mold send out to make new mold, How are they formed and releases. Is the water in lakes that have “little green clouds” Are the clouds made from dew, why do they look like “earthy particles” and some green streaks, each streak is about as thick as a human hair, coiling in spirals, like snakes. Here is a description: Many little animals…Some were roundish ….Others, a bit bigger,…(were) oval (egg-shaped). On these last I saw two little legs near the head….Two…fins (were) at the rear end of the body….These animalcules (little animals) had divers (different ) colors. Some …(were) whitish and transparent (clear) …Others (had) green and glittering …scales…The motion of these animalcules in the water was so swift, and so various…that it was wonderful to see. These creatures are a thousand times smaller than the smallest living thing I have seen so far. A tiny, spiderlike mite that lives on cheese. When I compared sizes, I speak of volume, not length. A cheese mite is smaller than the dot at the end of this sentence. A “little animal” was about one tenth as long as a cheese mite. Rain Water This water that has been observed has stayed in a pot for several days Observation: Sometimes stuck out two little horns…. (these) moved after the fashion of a horse’s ears. The part between these little horns was flat, their body else being roundish….it ran somewhat to a point at the hind end…. (At this) end it had a tail, near four times as long as the whole body.. these are the most wretched creatures that I have ever seen. I feels sorry for them because they seem to get their tails caught on things all the time. When this happens: They pulled their body out into an oval. . . . (They) struggle(d), by strongly stretching themselves, to get their tail loose….Their whole body then sprang back towards the end of the tail….Their tails then coiled up serpent-wise….This…stretching out and pulling together of the tail continued. Tiny, hairlike structures went all around the top of each creature bell-shaped body. These hair formed a circle. From single angles, the hairs at the ends of the circle look bunched together. These bunches are what I thought were horns ( I had had not seen the other hairs at all). I now know that these hairs stirred up the water. These animals attach themselves to water plants. I soaked pepper in water for three weeks. I wanted to make it soft. Then the larger pieces —Preceding unsigned comment added by 71.191.42.20 (talk) 15:23, 5 June 2008 (UTC)

Hmm, is this homework? Ζρς ι'β' ^¡hábleme! 15:33, 5 June 2008 (UTC)

Seems to be a bunch of incoherent babblings. Clarify the specific question you are asking. Jdrewitt (talk) 16:00, 5 June 2008 (UTC)

The text from "here is a description" on seems to be at least partly from Antonie van Leeuwenhoek. I think just the part before that is the actual question(s). Anonymous, try asking fewer questions at a time. --Allen (talk) 16:48, 5 June 2008 (UTC)

I count 19 separate questions, all of which could be answered by looking at blood, blood cells, cell (biology), cell nucleus, eye, muscle, chalk and clouds. D0762 (talk) 16:48, 5 June 2008 (UTC)

Brain

What is the result(or complication,s)of scatterd leigon's through out the light matter's of the brain?--216.37.249.110 (talk) 17:31, 5 June 2008 (UTC)

Scattered legions are typically indicitive of occupation by the Romans. Complications include widespread viticulture, use of Latin and Jupiter worship...... Seriously though, a useful article... here. Fribbler (talk) 18:24, 5 June 2008 (UTC)

No, no, the op did not ask for legions, they asked for leigons which might be like reading the tealeaves in geometric figures. SpinningSpark 19:09, 5 June 2008 (UTC)

Gentlewikipedians, it is considered bitey to poke fun at a questioner. To demonstrate the shred of sense of humor it takes to ridicule mispelling is not as good as demonstrating the intelligence it takes to figure out what it means and answer accordingly. We should also take pride in invariably exhibiting goodwill and a welcoming posture. And don't forget the roads. And the public baths. But really, don't bite. --Milkbreath (talk) 19:20, 5 June 2008 (UTC)

Aw, come on let us have a little fun ;-). Ζρς ι'β' ^¡hábleme! 19:48, 5 June 2008 (UTC)

I'm with Milkbreath on this one. If you want to have fun biting newcomers, do so with the ones that come here and write out their homework questions word for word (question numbers and all!). This is a serious question, it deserves a serious answer, regardless of an easily made spelling mistake. --Tango (talk) 21:26, 5 June 2008 (UTC)

True. Sorry OP! I did provide an answer in my response at least, though. :-) Fribbler (talk) 21:38, 5 June 2008 (UTC)

Sorry too, without Fribblers excuse. SpinningSpark 21:46, 5 June 2008 (UTC)

Wow, Tango, please calm down. I truly did not mean to offend anyone. I was only joking. Sorry, Ζρς ι'β' ^¡hábleme! 23:11, 5 June 2008 (UTC)

And to help the original poster avoid these hazing rituals in the future, the word meant was presumably lesions. Confusing Manifestation(Say hi!) 23:33, 5 June 2008 (UTC)

Isn't it a homework question?  :-} Julia Rossi (talk) 04:21, 6 June 2008 (UTC)

Right i'm going to be useful and provide a decent answer for the OP here. I presume you meant lesions, in which case it depends very much where the lesions are in the brain. There are far too many nerves which stimulate far too many different processes to give you a definitive answer but to see a good example, i'd see multiple sclerosis, probably the best known of all the lesion-related diseases (although it is autoimmune). Regards, CycloneNimrod ^talk?_contribs? 10:57, 6 June 2008 (UTC)

There are too many variables to predict what would happen: location, total volume of brain affected, lesion size, etc. But one very interesting phenomenon whereby the brain is injured by diffusely scattered lesions is called postperfusion syndrome, or "pump head". It has been proposed that cardiopulmonary bypass generates scores of tiny air emboli that travel to the brain and cause cell death, leading to subtle neurocognitive changes. --David Iberri (talk) 00:09, 8 June 2008 (UTC)

Possessions

Hi. I am watching an episode of Most Haunted. It showed a man being "possessed" by two different spirits in succession. I have witnessed with my own eyes what seemed to be a woman being possessed and, apparently, exorcised. Some reliable acquaintances of me have described similar incidents to me. Could there be any truth to such "possessions". If not, what is the scientific explanation? Thanks. ReluctantPhilosopher (talk) 18:28, 5 June 2008 (UTC)

There is no truth to "demonic possession". There are many possible explanations for the phenomena that have led to a belief in demonic possession, among which are ergotism, mental illness (including especially histrionic personality disorder and monomania), and fraud (where a charlatan and his accomplice simulate the event). Hoax for hoax' sake can't be ruled out, either. Mass hysteria, another name for fervent religious belief, can lead people to believe they've witnessed what they have in fact not. --Milkbreath (talk) 18:46, 5 June 2008 (UTC)

Take a look at this link [3].--Eriastrum (talk) 18:51, 5 June 2008 (UTC)

Also see Spirit possession. A lot of people believe in spirit possession... I don't personally, but it is an integral part of some religions, like Haitian Vodou. So to say there is no truth to it is akin to saying there is no God; in other words, it might be a statement beyond the scope of science as the field is generally understood. Also, besides actually believing in spirit possession, there is a third explanation besides mental illness and dishonesty. This third explanation is when one is raised in a culture that believes in routine spirit possession, even healthy people can have experiences that they interpret as spirit possession. --Allen (talk) 19:22, 5 June 2008 (UTC)

Ok, Milkbreath should probably have said "As far as science is concerned, there is no truth to demonic possession", but considering this is the science reference desk, he probably considered that implicit. Your third explanation is what, I think, he meant by mass hysteria. --Tango (talk) 21:22, 5 June 2008 (UTC)

Sorry; I don't think I was clear enough. I actually was assuming that Milkbreath meant "as far as science is concerned." My argument is that, as far as science (as commonly understood) is concerned, science has nothing to say about the truth or falsehood of spirit possession, because belief in possession doesn't necessarily entail any empirical claims. I know it could be argued either that belief in possession does entail empirical claims, and it can also be argued that science does have things to say about non-empirical claims. I just wanted to point out that those aren't the kinds of responses you typically get from scientists about religious claims. --Allen (talk) 22:16, 5 June 2008 (UTC)

(ec) I am not a scientist, so I have nothing to lose by telling the truth—no faculty, no students, no grant granters, no constituency, no book-buying public. There is no such thing as a demon. My mother could tell you that, and she's no scientist, either. She would add that there's no such thing as monsters under the bed. But some of us will not be comforted, I guess. --Milkbreath (talk) 22:40, 5 June 2008 (UTC)

(Remove indent) ...science has nothing to say about the truth or falsehood of spirit possession. I disagree. Science may well say that given all of Milkbreath's alternatives, the chances that possession is true are pretty much negligible. Zain Ebrahim (talk) 22:35, 5 June 2008 (UTC)

Science doesn't give absolute answers, it never has and it never will. The closest you get is whether or not there is significant evidence to support a theory, and in the case of demonic possession, there is no significant evidence to support it, so scientists will generally assume that it doesn't exist (unless they are specifically testing for it, of course). If there is demonic possession but it is in all ways indistinguishable for psychosis, then it isn't a scientific matter, and it is still accurate to say that, as far as science is concerned, there is no such thing (or, that it is just a form of psychosis). That's not saying there is no such thing, just that there is no empirical evidence to suggest that there is. --Tango (talk) 22:59, 5 June 2008 (UTC)

Perhaps another way of putting that is "if there is no way, even in theory, to tell the difference between psychosis and demonic possession, then there is no difference between the two and now we're just talking about which name we should give this phenomenon". For the moment, "psychosis" is the more suitable name so I guess it will stick until psychotic patients' heads start spinning around. --Sean 23:07, 5 June 2008 (UTC)

Don't all these arguments apply to God just as easily as to demons? Milkbreath, you're disclaiming a scientific perspective... but Zain, Tango, Sean, would you all be just as quick to say that, as far as science is concerned, there is no God? You'd have high-profile company, of course, in people like Christopher Hitchens... but I still think you'd be in the minority. --Allen (talk) 01:21, 6 June 2008 (UTC)

I am not making an argument. I am stating the obvious plainly. There is no such thing as a demon. --Milkbreath (talk) 01:36, 6 June 2008 (UTC)

I don`t see why any theory, regardless of whether God or demons are involved, cannot be tested using the scientific method. The principle of science (and of all academic disciplines) is, in brief, that an alleged phenomenon which cannot be proven convincingly is false. Thus, unless evidence that is more than 50% likely to be true is found supporting the existence of demons, one assumes demons are non-existant. The same concept applies to God; since there is no convincing reliable evidence that deities exist, they do not. One cannot simply read a book written thousands of years ago by unknown authors and consider it scientific proof. --Bowlhover (talk) 03:16, 6 June 2008 (UTC)

I'm a Christian and I consider myself a scientist too, but I keep the two very separate. "...that an alleged phenomenon which cannot be proven convincingly is false" is a bit ridiculous by any standpoint because even scientifically it doesn't make sense. In science there is no such thing as proof. Nothing is proven, at all. Nothing is disproven, at all. It just becomes overwhelming likely in either direction. If someone is looking for answers that science can't provide, religion can be the answer. On the other hand, religion clearly can't explain a lot of things and that's where human nature, and science, comes into it. But again this is just my opinion. Regards, CycloneNimrod ^talk?_contribs? 10:54, 6 June 2008 (UTC)

You're right, "proven" is the wrong word, "demonstrated" would be better. Science is about rational, logical explanations for things, and that requires empirical evidence. Religion is about faith, it's a completely different matter. People like religion because of a basic fear of the unknown. Science can't answer every question we want answered (yet, at least), so people look elsewhere for the answers. The answers aren't particularly meaningful, but people don't really care about that, they just want an answer, and anything will do. This is the science reference desk, however, so we're interested in the scientific point of view, and in that point of view there are no demons and no gods, since there is no empirical evidence for them. --Tango (talk) 14:15, 6 June 2008 (UTC)

My intention was to say "that an alleged phenomenon for which there is little convincing evidence..." Religion can indeed provide answers, but those answers are not based on evidence but on the blind belief called faith. --Bowlhover (talk) 02:58, 7 June 2008 (UTC)

All right, thanks fellas, your responses were really illuminating. However I don't think we have to lump the existence of God with probable hoaxes like possessions, that's a different concept which may take many meanings. Thanks again! ReluctantPhilosopher (talk) 09:17, 6 June 2008 (UTC)

Well, philosophically there is not too much difference. One religion's gods may well be another religions demons. Religions have evolved over time, and there is a lot of disagreement about which (if any) is right. On this I'm with Dawkins - why would one believe in one particular religion, but not into any of the other equally well supported (by evidence, not infrastructure, of course) ones? --Stephan Schulz (talk) 13:01, 7 June 2008 (UTC)

What I meant was one can have a religous view in which one believes in a higher spiritual truth or reality or power, but doesn't believe that the so called possessions are due to demons. For instance I consider accounts of possessions as superstitious and false but I still believe in (for very good philosophical reasons) in a higher truth which I endeavour to find out. And this higher truth doesn't have to be a "personal" good necessarily, nor a god of the gaps, but a real experience which solves the mystery of life. ReluctantPhilosopher (talk) 16:29, 7 June 2008 (UTC)

One should believe in one religion and consider all other religions bullshit because one has been grown in a culture that blindly believes in one religion and considers all other religions bullshit. I you think about it religion may be viewed as an organism which evolves and does anything it can to protect it's self. Bastard Soap (talk) 19:27, 7 June 2008 (UTC)

I think we might be getting a little off-topic... --Tango (talk) 20:29, 7 June 2008 (UTC)

Social-dependance on alcohol

People claim that smoking relieves stress but are wrong because the equilibrium that the brain strives to attain actually results in smokers being more stressed when not smoking, such that their averaged-stress level is no better than that of non-smokers. Can the same be said of people that drink to relieve inhibitions? Do the brain compensate and make them more nervous and dependent on alcohol? Why? ----Seans Potato Business 19:53, 5 June 2008 (UTC)

No. If memory serves, alcohol is a depressant and nicotine is a stimulant. Drinking really does relax you, even if you're not an alcoholic. --Tango (talk) 21:12, 5 June 2008 (UTC)

Alcohol addiction can lead to harsh withdrawal symptoms such as tremor, seizures, etc. This would be considered a stimulated state, though stress is probably not the right word. An alcoholic drinks alcohol because they are dependant, and need it to prevent the withdrawal symptoms. Most substance addictions lead to things like desensitization and downregulation of receptors, leading to physiological tolerance, so an increased dose is needed, until a point where the body is reliant on that substance for it to maintain properly. --Mark PEA (talk) 22:14, 5 June 2008 (UTC)

Of course, if you are an alcoholic, you'll be dependant on alcohol in much the same way a nicotine addict is dependant on nicotine and will get similar withdrawal symptoms. However, the question was about the fact that it's wrong to say smoking relaxes you, since it's actually just relieving withdrawal symptoms, and whether the same can be said for alcohol, which it can't. Alcohol relaxes you whether you are addicted to it, or not. --Tango (talk) 22:54, 5 June 2008 (UTC)

Withdrawal symptoms for alcohol can be quite severe, see Delirium tremens. No such thing for nicotine AFAIK. So no, withdrawal symptoms are definitely not similar. --Dr Dima (talk) 23:39, 5 June 2008 (UTC)

True. How about "and will similarly get withdrawal symptoms"? The symptoms themselves may not actually be the same, but the basic idea of withdrawal is a constant. --Tango (talk) 00:11, 6 June 2008 (UTC)

Drinking really does remove inhibitions. Mostly has to do with fear. Fear is an inhibitor. Drinking dulls the senses and the emotional aspects along with it. ScienceApe (talk) 01:24, 6 June 2008 (UTC)

That's kinda semantics though. The end result is ultimately a dampening of one's "inhibitions" through diminutive senses, in this case, fear. Wisdom89 _{(T / ^C)} 02:50, 6 June 2008 (UTC)

Maybe another factor for an alcohol-assissted confidence boost is that you could blame it should something goes wrong. You could say that, "well I made fool of myself on the party because of the alcohol maybe the host should have provided a less intoxicating drink".--Lenticel ^(talk) 03:53, 6 June 2008 (UTC)

Fear isn't a sense, it's an emotion. --Tango (talk) 14:07, 6 June 2008 (UTC)

Alcohol affects the parts of the brain that control judgment. Part of the ability to feel fear comes from the ability to perceive consequences. Alcohol lessens the ability to perceive consequences, and thus reduces fear and inhibitions. Also, as has been mentioned before, alcohol is a nifty excuse in our society (NOT speaking from personal experience!) for having behaved badly or stupidly, as long as you don't do it too often. "You slept with WHOM? Oh, I get it . . . you had a few too many." (Spoken with a condescendingly sympathetic smile.) 66.215.224.253 (talk) 20:05, 7 June 2008 (UTC)Aletheia —Preceding unsigned comment added by 66.215.224.253 (talk) 20:01, 7 June 2008 (UTC)

Inner workings of the package that Edge shaving gel comes in

If I remember correctly, as you use up a can of Edge shaving gel, the can feels like it is empty at the bottom and full at the top. This is different for most other similar packaged comsumer products - the liquid inside a normal can of shaving cream obviously sits at the bottom of the can. So, I have two questions:

• What exactly is going on inside the Edge can? Is there a pressurized balloon that expands pushing out product from the bottom to the top of the can?
• Can you think of any other types of products that are packaged in a similar way?

ike9898 (talk) 21:56, 5 June 2008 (UTC)

An alternative guess: the cream could be in a pressurised balloon (or other kind of container) which shrinks as it's used up, and is attached to the top on the can. --Tango (talk) 21:58, 5 June 2008 (UTC)

I see a few patents for "floating piston" designs. Essentially the bottom appears to be a pressurized compartment (injected via the black rubber valve after the can is gel-filled and sealed), separated by a rubberized disk from a top compartment containing the gel. Gas expands, pushes piston up, forces gel out the top. DMacks (talk) 06:08, 6 June 2008 (UTC)

From my experience working for Gilette which makes a similar shave gel...the 'gel' is actually inside a pouch that is, as the op said, attached to the top of the can. The remainder of the can is filled with a pressurized inert gas that squeezes out the gel when the button is pressed on the top, which establishes a pressure gradient allowing for the squeezing to take place. EagleFalconn (talk) 14:18, 6 June 2008 (UTC)

Can you speculate as to why such an unusual package is needed for this product? ike9898 (talk) 19:27, 6 June 2008 (UTC)

The common alternative for pressurize dispensing would be to have a siphon/dip tube going to the bottom of the container, with the gas "on top pushing down". That arrangement only works if the can is held vertically upright, however, whereas the squeezed-bag design works in any orientation. DMacks (talk) 19:50, 6 June 2008 (UTC)

Thanks, guys. ike9898 (talk) 20:26, 6 June 2008 (UTC)

Open access - self archiving

If someone self-archives their scientific papers, can they get a link on pubmed so people know that it's self-archived? Otherwise people have to cross their fingers and search, usually in vain, just in-case. ----Seans Potato Business 22:01, 5 June 2008 (UTC)

That's something to ask PubMed. If someone self-archives a scientific paper that wasn't published in any journal recognized by PubMed, then of course PubMed wouldn't link to it. On the other hand, if someone archives an article that is published in a recognized journal, if I were PubMed I wouldn't link to it. Links not under PubMed's control can become invalid, and maintaining a database of external links would be a nightmare. ~Amatulić (talk) 18:06, 6 June 2008 (UTC)