Wikipedia:Reference desk/Archives/Science/2008 May 3

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May 3

Chemical unbalance in clinical depression

Is there any empirical way (blood test or whatever) to check a chemical unbalance in the case of clinical depression? SaltnVinegar (talk) 01:09, 3 May 2008 (UTC)

Generally no. This is why anti-psychiatry people claim there to be a biopsychiatry controversy, and that the lack of biomarkers for psychiatry diseases leaves it in the realm of pseudoscience. Depression is typically diagnosed according to the guidance set out in Diagnostic and Statistical Manual of Mental Disorders, using the Beck Depression Inventory or Major Depression Inventory. There are technique for measuring local variations in neurotransmitters but they tend to be either very invasive, and are typically done on experimental animals, or limited to neuroimaging of the brain Rockpocket 01:23, 3 May 2008 (UTC)

The only way to definitively determine such correlations would be to measure the activity and secretion of neurotransmitters (norepi, serotonin, dopamine) in different regions of the brain along with the expression of their receptor subtypes. It's just not feasible. Wisdom89 _{(T / ^C)} 01:54, 3 May 2008 (UTC)

OK, it is not feasible by living patients. However, what about analyzing the brain of suicide victims? Would that provide some insight if the person was depressed? SaltnVinegar (talk) 01:54, 4 May 2008 (UTC)

Frodl T, Scheuerecker J, Albrecht J, et al. (October 2007). "Neuronal correlates of emotional processing in patients with major depression". World J. Biol. Psychiatry: 1–7. doi:10.1080/15622970701624603. PMID 17965984.

Bean Alcohol

Way back on 2007 August 7 someone asked about why beans aren't used as a source of alcohol. That question never seemed to get a good answer. Anybody who can offer speculation today? 76.228.195.100 (talk) 01:14, 3 May 2008 (UTC)

Link to the August 7 2007 thread. --hydnjo talk 01:27, 3 May 2008 (UTC)

You can make it from coffee beans apparently. Perhaps the idea is to stop you falling asleep so you drink more! And heres someone doing it from cocoa beans. Sadly, no process for alcohol from baked beans - too difficult to remove the tomato sauce perhaps.SpinningSpark 08:54, 3 May 2008 (UTC)

IMHO the low sugar/stach contents of beans (as mentioned at the time) is probably a significant factor Nil Einne (talk) 08:07, 4 May 2008 (UTC)

The best I can come up with is that when starchy items (like grains) ferment/rot, they just smell "off", whereas when proteinatious items ferment/rot they smell *terrible* (smelling rotten chicken is an experience I never want to repeat). I would guess that the intrepid people throughout history who tried to make bean beer smelled the result and dumped it as unfit for human consumption. Although, there are a lot of dishes in the world which are prized in spite of (because of?) smelling like refined torture. (Durian, Nattō, and Hákarl come to mind.) Another thing to remember is that, until recently, most alcoholic fermentations happened with natural yeasts. For example, wine yeasts were simply the yeasts which happened to be on the skins of the grapes at the time when they were crushed. It could be that bean-mash doesn't promote the growth of the natural surface yeasts which would result in a alcoholic beverage, or the beans are too contaminated with other yeasts and bacteria which would cause vinegar or other fermentation products, instead of alcohol. -- 128.104.112.85 (talk) 17:12, 4 May 2008 (UTC)

"It smells horrible." is an answer I can definitely believe. 76.199.151.77 (talk) 04:28, 21 May 2008 (UTC)

"That's not true. There's some group in Tucson that does that every winter."

I read a lot of good information on some websites about it but discovered later that the pages had been deleted. I couldn't even find them cached on Google. Anyone know why bean alcohol would be so quickly targeted?

Longetivity

Do smarter people live shorter lives? There's a chinese saying that says "God is jealous of the smart", implying that smarter people live shorter. Is this true? 99.226.39.245 (talk) 01:21, 3 May 2008 (UTC)

According to this study (which also refers to other studies that report the same thing), intelligence correlates to longer lives, though no one is quite sure why. It's possible that more intelligent people (whatever that means) make smarter lifestyle decisions. Clarityfiend (talk) 01:38, 3 May 2008 (UTC)

It's also possible that it opens up more opportunities to less dangerous jobs. AlmostReadytoFly (talk) 08:53, 3 May 2008 (UTC)

Or simply better paying jobs allowing for a better diet and medical care. --Tango (talk) 12:46, 3 May 2008 (UTC)

Or stupid people are better at getting themselves killed. Or God just does not like them. SpinningSpark 13:21, 3 May 2008 (UTC)

It doesn't address the human case, but some research in other animals suggests that "smarter" ones appear to actually live less long (in accord with the original question's quote, and contrary to the typical correlations in humans). This answers one problem of evolutionary psychology: we empirically know that we can breed certain animals to get smarter (by measures such as learning ability) in relatively few generations. If we assume that this would be a good trait for survival, that leaves a problem: why hasn't this already happened in nature? One answer is that, in fact, it isn't good for survival, and that's why it hasn't happened. The reason why or the scope of the experimental findings is not agreed upon. Here is a summary in The Economist of a journal article that appears not to be out yet, but will be in Evolution soon. --Delirium (talk) 13:31, 3 May 2008 (UTC)

So there's no evidence that thinking too much is stressful or causes a reduction in lifespan? 99.226.39.245 (talk) 18:01, 3 May 2008 (UTC)

I would take issue with the assumption that thinking too much is stressful. The stress arises when you've found the correct answer and your boss (or lead wolf if we go with the animal example) won't listen and just bites you. Lisa4edit71.236.23.111 (talk) 21:04, 3 May 2008 (UTC)

Not exactly on topic but the Chinese prover that you've mentioned (天妒英才) isn't really taken literally, rather it's usually used to exclaim the early/unexpected death of an important figure. --antilived^{T | C | G} 01:47, 4 May 2008 (UTC)

Rolling

If you let a ball go on a frictionless inclined plane, will it roll? —Preceding unsigned comment added by 76.69.240.138 (talk) 01:34, 3 May 2008 (UTC)

If you mean down, yes. If you mean up, no. Wisdom89 _{(T / ^C)} 01:52, 3 May 2008 (UTC)

Wait, I think I misread your question...rolling specifically. That's very interesting. I'd surmise, that no, it wouldn't roll at all, it would slide down due to gravity and accelerate according to that fixed phenomenon. Wisdom89 _{(T / ^C)} 01:56, 3 May 2008 (UTC)

It might if you rocked it first. Clarityfiend (talk) 02:13, 3 May 2008 (UTC)

It might rotate , depending on exactly how you "let it go", but it wouldn't "roll", in the sense of whichever point was in contact with the plane at any moment being stationary. It would slide down the plane while rotating at a constant speed (possibly zero). (Was this homework? If so, ignore this and work it out for yourself, please.) --Anonymous, 03:36 UTC, May 3, 2008.

I think even without friction, the ball will roll since the normal force and weight force are not along parallel axes. This will result in a torque. Nimur (talk) 02:51, 3 May 2008 (UTC)

Naturally, I'm assuming an ideal situation, whereby I let go of the ball perfectly (i.e. without any initial torque). In response to Nimur's statement, while gravity has a vectorial component parallel to the surface, it's going the wrong way to cause rotation. Besides, the force of gravity is applied on the center of mass, not at the end of ball. When I asked the question, I was pretty sure that it wouldn't roll, but I just wanted to make sure. —Preceding unsigned comment added by 76.69.240.138 (talk) 03:10, 3 May 2008 (UTC)

So, just to sum up, the ball will not start rolling, because there is no torque about the center of the ball. The normal force acts along a line through the center, and the force of gravity acts on every point of the ball equally, so neither of them has torque. Only friction could cause torque. —Keenan Pepper 03:27, 3 May 2008 (UTC)

Whoops. I should have drawn a diagram! Nimur (talk) 14:44, 3 May 2008 (UTC)

For the specified conditions, the ball will slide down the slope without any change whatsoever in its rate of rotation. Edison (talk) 03:44, 3 May 2008 (UTC)

By the same logic, a sharp pencil or biro balanced on its writing end would also slide down the inclined surface instead of tipping over. Verrrry interrresting….Myles325a (talk) 01:03, 10 May 2008 (UTC)

Naga Jolokia

Is the Naga Jolokia pepper used in any cuisine? If not, has anyone ever actually eaten one? Interactive Fiction Expert/Talk to me 03:40, 3 May 2008 (UTC)

This http://www.fiery-foods.com/ffshow/nffs2007pics.asp and 5,520 other hits when googling for "Naga Jolokia" recipe would indicate yes, and in any cuisine that aims for hotter than hot. Lisa4edit71.236.23.111 (talk) 05:47, 3 May 2008 (UTC)

(e/c) According to the ref's in the article, yes it is used. The key here is whether the pepper is diluted or eaten as is. I've tasted pure capsaicin extract, approximately the same heat in Scoville units, don't try this at home. However, no matter how hot the pepper, if you chop it up finely or cook it long enough, the heat infuses through the entire dish. So I think the answers here are yes and yes. Franamax (talk) 06:01, 3 May 2008 (UTC)

Can you see colour in the dark?

Your in a dark room. It is not dark enough that you walk into things but its not exactly bright either. Theres object around you, do you see the colour of the object or shades of grey?. I remember reading we have 4 kinds of something (forgot what) three are for colour one is for seeing in the dark. Do some people see better than others in the dark? or even one eye better than the other? Kingpomba (talk) 07:09, 3 May 2008 (UTC)

See rod cell. --Prestidigitator (talk) 07:30, 3 May 2008 (UTC)

The "4 kinds of something" you are referring to are the three types of cone cell which generally perceive colour in good light conditions, and one type of rod cell which determines light in dim conditions. The monochromatic vision you describe occurs in most people at luminance levels of 10^-2 to 10^-6 candela/m².

Do some people see better than others in the dark? Yes. The US military review, A Study of Individual Variability in Dark Adaptation and Night Vision in Man studied the "origin and magnitude of inter- and intra-individual variation in ... dark adaptation and scotopic vision." Concluding "that recognition of individual variation is critical to the concept of selecting key individuals for specific duties requiring night vision capability." In other words, its a good idea to send people who see the best in the dark on night missions. Rockpocket 07:43, 3 May 2008 (UTC)

Also see Nyctalopia. --Lisa4edit (talk) 09:06, 3 May 2008 (UTC)

I have no background in this area, but it stands to reason that if you see anything at all in a dark room, there must be a little bit of light, hence some photons bouncing around. If they hit a surface of a certain color, that object will still absorb some of the light energy and leave part of it to bounce off. The part that bounces off is what we normally see as the "color" of the object. So, regardless of whether it is dark or not, the photons will still collide with objects and bounce off with the corresponding color. You probably won't be able to see the color, depending on the amount of photons reaching your eye (i.e. how dark it is). Leeboyge (talk) 21:39, 3 May 2008 (UTC)

Yes, every visible photon has a colour. However, rods only detect the presence of a photon, not what colour it is (at least not significantly - they might detect it slightly, I don't know). You need the cones to tell what a photon is, and they only work if there are enough photons. --Tango (talk) 21:48, 3 May 2008 (UTC)

No, rods don't tell you the color of light. For that matter, individual cones don't either. The three different kinds of cones have different response curves to different frequencies of light, and that information has to be synthesized into a sensation of color. If all you have is the signal from the rods, you have no color information to work with. Of course rods as well have a response curve, but it's the same for all the rods, so you can't differentiate color. --Trovatore (talk) 21:56, 3 May 2008 (UTC)

Has anyone ever tried whether it is possible to see Fechner colors in low light conditions. If the cones are involved, that shouldn't work. If it's "all in the brain" it might. 71.236.23.111 (talk) 03:47, 4 May 2008 (UTC)

Explain Jargon: 'decay'

From the article Optical pumping:

"...however due to the cyclic nature of optical pumping the bound electron will actually be undergoing repeated excitation and decay between upper and lower state sublevels..."

How to give a proper (internal) link to the underlined 'decay'? - Justin545 (talk) 10:18, 3 May 2008 (UTC)

I'd say Atomic orbital is your best bet. It doesn't have the word in it, but explains the concept. I think you know the term describes the electron moving to a lower energy state, which used to be described as "falling/decaying to a lower orbit". The article already links to Energy level which would be my other choice. Orbital decay deals with satellites. I think the problem you are encountering is that while the specialists have moved on to new concepts Electron configuration Quantum states the other fields quoting them still use classical systems and vocabulary. That makes linking rather difficult. Hope this helps. Lisa4edit (talk) 11:50, 3 May 2008 (UTC)

Thanks. Maybe that's why I never see a linking 'decay' in related articles. But do you think if we should create a brand new article or a redirect page for it? There seems to be no relevant articles on the disambiguation page of decay. - Justin545 (talk) 12:20, 3 May 2008 (UTC)

I don't think you should create a new article. I would say that the article Excited state is the right place to explain this meaning of decay. A link could then be put in from the Decay disambiguation page. Both Energy level and Excited state are already linked from the Optical pumping article so I don't think any new links are required in that article. You could join the two terms together in one link though like this:- excitation and decay. SpinningSpark 12:31, 3 May 2008 (UTC)

What is really missing is an unambiguous term for this type of decay, analogous to "radioactive decay", "orbital decay", etc. I can't think of one, however. "Electron decay" doesn't sound right, and "atomic decay" seems to be a synonym for radioactive decay. If there were an unambiguous term, that could be redirected to Excited state, and links could be made to the unambiguous term in articles and on the dab page Decay.--Srleffler (talk) 18:18, 3 May 2008 (UTC)

I've changed the link according to SpinningSpark's suggestion. I think the meaning of 'decay' would be opposite to the meaning of 'excite' but you know I'm not a physicist and not sure about it. According to Lisa4edit, I may name the new page tile as 'Energy Level Decay' or 'Decay (energy level)'. Make the link be excitation and decay may not be sufficient. As we can see, we can not event find any 'decay' in the article Excited state, which would still make the meaning of 'decay' ambiguous to a lay reader. Therefore, I tend to creat a new / redirect page for it to explain it explicitly. If not, it would be better to extend the article Excited state and explain 'decay' in the aritcle explicitly. - Justin545 (talk) 00:22, 4 May 2008 (UTC)

Not sure that I'd like that title. The exitation and decay terms are already explained in the continuing sentence "excitation and decay between upper and lower state sublevels." What you are trying to achieve is to make that phrase understandable to a layperson. That is why I suggested linking to Atomic orbital, and Spinningspark suggested Excited state. The former explains the classical model of electrons in orbits. Depending on what your educational background in Physics is, this may be more accessible to you than the latter link which homes in on the process based on modern concepts. I'm not sure we need a new stub for "decay". On the one hand one could explain the concept both in classical view and modern terms there. On the other hand we might end up with a stub that never goes very far; and particularly in Physics, you'd open a Pandora's box of terms that would have to be explained based on various concepts and at various levels of depth. I would not find either 'Energy Level Decay' nor 'Decay (energy level) a sufficiently clear and understandable definition. Your best bet might be to add a couple of phrases to your Optical pumping page. It is not that extensive yet that it could not accommodate another paragraph. Lisa4edit71.236.23.111 (talk) 03:22, 4 May 2008 (UTC)

When I read Optical pumping and Trapped ion quantum computer, I was confused. That's why I think if I can do somthing to improve the articles and make it more clear. Unfortunately, I am one of the layperson we are talking about and I'm not a host of Optical pumping which means I may not be qualified to make that phrase understandable. As you said, the created new page could end up with a stub that never goes very far. Therefore, extending Excited state and link to it may be the alternative choice. The first consideration is that the jargon in question also appears in the other articles. For example:

• Trapped ion quantum computer: "...Hyperfine qubits are extremely long-lived (decay time of the order of thousands to millions of years) and phase/frequency stable (traditionally used for atomic frequency standards). Optical qubits are also relatively long-lived (with a decay time of the order of a second)...a laser couples the ion to some excited states which eventually decay to one state...If the ion decays to one of the other states, the laser will continue to excite the ion until it decays to the state that does not interact with the laser...resulting in a photon being released when the ion decays from the excited state. After decay, the ion is continually excited by the laser and repeatedly emits photons..."

(which would probably give a second jargon 'decay time'. again it's ambiguous to a layperson like me)

Using links may reduce the job to explain it each time it appears in an article. The second consideration is that I think a jargon can not be explained by an article unless it appears in the articles at least once. As we can see, the jargon 'decay' can not be found neither in Excited state nor in Atomic orbital, which meams they are likely not formal articles describing 'decay'. I believe a good article should be "accessible to the lay reader and yet are also useful to the professional working" as stated in Wikipedia:WikiProject Physics. - Justin545 (talk) 06:15, 4 May 2008 (UTC)

I think the standard dictionary definition is sufficient: "to decline from a sound or prosperous condition". Granted, "sound" and "prosperous" are not the terms a physicist would use, but in the context of the original sentence ("decay between upper and lower state sublevels") one can figure out that the decay is this transition between the upper level and the lower level (whatever they are) without having to be a physicist. --Itub (talk) 17:10, 7 May 2008 (UTC)

What is meant by "a void has a time dimension"?

I read somewhere that it's impossible to picture "nothing". Most people will simply picture a black void. The book went on to say that it's not really nothing you're picturing because it has dimensions including a time dimension. Dimensions I can understand because your mental image does have a definite measurement, but I dont understand what a time dimension is. How can a void ,mental or otherwise,have a time dimension? How does anything have a time dimension?--Sam Science (talk) 10:36, 3 May 2008 (UTC)

See Fourth dimension (the first paragraph in particular - ignore that stuff about a spatial 4th dimension) and Spacetime#Concept with dimensions. Zain Ebrahim (talk) 11:13, 3 May 2008 (UTC)

Okay those articles suck. If you wanted to refer to a point in 3-space you would need 3 co-ordinates (commonly refered to as x, y and z). But that point may exist at various positions in time so if you wanted to refer to just one of those, you'd need to define a 4th dimension to represent time. This may be extended to include constructs of the mind. Zain Ebrahim (talk) 11:23, 3 May 2008 (UTC)

I don't know if this will help you, but I found it useful. Look at Necker cube. Stare at the cube in the first picture. Note what you see. This is your reality at T1. If you stare for a longer time the surface that you see as "front" will change. Call the moment it changes T2. So what you see as reality depended on the time. Another way to visualize it is the impossible cube at the bottom. If you imagine being in a vehicle that moves around the sculpture at a certain time it will appear to be a cube. --Lisa4edit (talk) 12:46, 3 May 2008 (UTC)

Circular Motion

A man whirls a stone round his head on the end of a string 4.0 m long.Can the string be in a horizontal plane? If the stone has a mass of 0.4 kg and the string will break if the tension in it exceeds 8n,what is the smallest angle the string can make with the horizontal ? What is the speed of the stone? Take 'g=10m/sec^2 —Preceding unsigned comment added by Priyank Sunil Jain (talk • contribs) 11:09, 3 May 2008 (UTC)

As it says at the top of the page, we will not do your homework for you. See circular motion and conical pendulum, and come back if you have any more specific questions. Algebraist 11:36, 3 May 2008 (UTC)

As a corollary, what angle below the horizontal would the string be at if the stone could be swung so as to travel at the speed of light? Is that the same angle as if a ball were rolling around in a hemispherical bowl at the speed of light? (and no quibbles please about how the speed of light is unreachable). Edison (talk) 19:21, 3 May 2008 (UTC)

If you ignore relativity, then (according to my quick calculations which could be wrong), you're going to get an angle of 2.5x10^-14 degrees. If you do take relativity into account, then you can't really ignore those quibbles. You could trying asking it about light, but I can't see how to make light go in a circle without being near a black hole, so I'm not sure the question is even valid. It's possible the angle tends to something meaningful as the speed increases, I'm not quite sure how to calculate it (in my first attempt, all the relativistic factors cancelled and I got the same answer as in the classical case, but I may well have missed something). --Tango (talk) 19:43, 3 May 2008 (UTC)

Yes, the string can be in a horizontal plane. Given this answer, your new question is: describe the circumstances. ( I have at least three different answere.) -Arch dude (talk) 19:44, 3 May 2008 (UTC)

Really? I can think of the stone being stuck to the ceiling, but that's it. Is that one of your 3? Give me a clue on the (other) 2/3. --Tango (talk) 19:50, 3 May 2008 (UTC)

Let's see ... the man could be in a microgravity environment or in free-fall, in which case the string will be in a plane, although the idea of a horizonal plane could be meaningless. Or maybe the stone is sufficiently aerodynamic to generate enough lift to counteract its weight, thus making the string horizontal. Gandalf61 (talk) 23:48, 3 May 2008 (UTC)

Nah, it's a combination of Longcat and the Noodly Appendages making it happen. That being said, I have this fun image of a tiny helicopter on the stone, keeping it up. Although just attaching a second string to some skyhook would be more sensible. -mattbuck (Talk) 06:47, 4 May 2008 (UTC)

Microgravity is ruled out by the question giving a value for g. The stone generating lift is a good idea, though. (The skyhook idea sounds equivalent to sticking it to the ceiling). We're up to 2 ways, then... one more to find? --Tango (talk) 13:23, 4 May 2008 (UTC)

A strong fan might do the trick, but might also create some interesting oscillations. --Prestidigitator (talk) 04:56, 5 May 2008 (UTC)

Are we (the question as asked, and all answers except for those with zero-G) assuming the string is weightless? Otherwise even if there were enough centripetal/lift/skyhook to keep the stone's circular path in the same plane as the center where the string is held, the string itself would sag (catenary or similar curve?). Thus, the angle of the string at the person's hand is not just a line to the stone. DMacks (talk) 06:51, 5 May 2008 (UTC)

Finding DNA of Jesus

• OK you guys, get this :

• Various relics of Christ have blood and flesh on them. [1]

• Some of these relics have been scientifically tested in laboratory at University of Bologna. [2]

• All of the evidence points to the fact that Jesus, AKA Lord incarnate, has AB RH+ blood type. The proteins are said to be extremely rare. [3]

• Also, the Civitavechia blood samples were analyzed and show that Mary has the same DNA as Christ. (ie Immaculate-Conception + Virgin Birth). [4]

• To understand what I mean, read this Telegraph article. [5]

• Some people are now saying that it would be theoretically possible to clone HIM. [6] [7]. However, no one can clone Virgin Mary, who in the past was needed fo birth.

• The Lord works in mysterious ways. How to explain this in light of Genealogical DNA test is unknown. 69.157.234.29 (talk) 13:18, 3 May 2008 (UTC)

You are assuming A LOT here. Not the least of which is that you assume that this person existed at all.--Shniken1 (talk) 13:26, 3 May 2008 (UTC)

There's plenty of evidence that Jesus existed - the big assumption is that he was the son of God. See Historical Jesus. --Tango (talk) 13:33, 3 May 2008 (UTC)

There's actually very scant evidence that there was one historical figure who corresponds with the guy named Jesus in the Bible. There are no contemporary accounts of Jesus from non-Christian sources (Josephus being a potential exception, though one that is almost certainly interpolated at a later date), and most of the Jesus-specific events of the New Testament are not verifiable either. The article in question to read is not "Historical Jesus", which is mostly about Jesus as described in the New Testament, but Historicity of Jesus, which is about whether he existed or not. All that being said, it is very hard to verify the existence of anyone that long ago if they weren't some major figure, and the early Christian church was a pretty small affair. --98.217.8.46 (talk) 13:51, 3 May 2008 (UTC)

The first couple links are stretches of the imagination. Nevertheless, the DNA contained in a dated blood sample wouldn't be suitable for human cloning most likely. It's a very complex process and has never been successful on a human. Wisdom89 _{(T / ^C)} 13:29, 3 May 2008 (UTC)

Assuming the relics are genuine (which is a very big assumption), I very much doubt there is a complete DNA sample there and one would be needed to produce a clone (as would the ability to clone humans, which we don't have yet). --Tango (talk) 13:33, 3 May 2008 (UTC)

Call me a skeptic, but most of your links seem to be lacking in any scientific merit, let alone peer review. The first link is a very biased site which mentions DNA tests by a Professor Dr. Odorardo who gets precisely zero Google hits except from clone sites or otherwise biased sites using the same source. Was this alleged work actually published? The Telegraph article linked is very skeptical also - not really helping your case. My opinion is that this entire thread should be deleted because it is not asking a genuine question and is contrary to the rules at the top of the page Do not start debates or post diatribes. The reference desk is not a soapbox SpinningSpark 13:46, 3 May 2008 (UTC)

Have you read those links? You assert that they determined that Mary and Jesus have the same DNA, but the link says instead that the blood found on an allegedly bleeding relic of Mary turned out to be a man's blood. That's not the same thing! If you want to honor your God use the critical faculties he gave you! --98.217.8.46 (talk) 13:59, 3 May 2008 (UTC)

Those relics have often been passed around from person to person, touched by thousands of pilgrims hoping for a miracle, kept in very unsterile conditions. Contamination with sweat (from touching), saliva (from kissing) and even blood from other people (such as wounded people who touched the relics hoping to be cured) is almost certain. To try to isolate one person's DNA and then identify which person it came from would be nearly impossible. Let's take for example the Holy Sponge (the sponge used to feed Jesus vinegar while on the cross and to mop away his blood and sweat): there have been several pieces of sponge throughout history that people have claimed belonged to Jesus - realistically, at most, only a few of them could have belonged to him. In the unlikely event that you were able to find a genuine piece of the Holy Sponge, you'd then have to remove all the bodily fluids of anyone who touched the sponge, any contaminants introduced by the vinegar and the fluids of other people who fed/cleaned with the same sponge. Since presumably Holy DNA doesn't look any different to normal DNA, you'd have no way of knowing which genes belonged to Jesus. Realistically, the only object you could have any hope of cloning Jesus from is the Holy Prepuce (his foreskin - the only part of Jesus's flesh not to ascend to Heaven), and even this has been faked numerous times throughout history - in fact, the Catholic Church now disputes the idea that the Holy Prepuce even existed in the first place. Laïka 14:31, 3 May 2008 (UTC)

Minor quibble, I don't think that it was actually His sponge in the sense of Him owning it. Matthew:27:48. SpinningSpark 16:21, 3 May 2008 (UTC)

We may define "faith" as the firm belief in something for which there is no evidence. Where there is evidence, no one speaks of "faith." We do not speak of faith that two and two are four or that the earth is round. We only speak of faith when we wish to substitute emotion for evidence. - Bertrand Russell Imagine Reason (talk) 15:03, 3 May 2008 (UTC)

I would rather say faith is belief in something for which there is not enough physical evidence and verification to constitute proof. Not necessarily none... Wrad (talk) 15:21, 3 May 2008 (UTC)

I would also say don't believe everything you read on the internet, especially about religion and Jesus :) . Wrad (talk) 16:23, 3 May 2008 (UTC)

Well, I guess this is one of the minor problems with science. There's too much scepticism. Sure, scepticism can be a good thing, similar to deletionism on Wikipedia, but with things that conventional science does not accept, you'd need absolute proof. For example, even the most authentic UFO cases are dismissed as "unexplained". Why? They argue that when the only possible explaination would be that UFOs/ailens exist, they dismiss it because they "cannot" exist. Why? Is there any proof that they can not exist? No. Is it actually true that if there is no absolute proof that they exist, only evidence, that they cannot exist? Absolutely not. Modern science also seems to be critical of religion, as in this example. Why? Well, because there supposedly is "insubstantial evidence". "Conventional" science accepts such theories as parallel universes, but cannot accept even remotely paranormal things such as cryptozoological creatures? There is evidence that they might exist, and none that they can't exist. This scepticism prevents science from turning into a junkyard, but surely a few of the things that conventional science does not accept might be real? Why do you need, say, 10x more evidence for things not accepted by conventional science, compared to say, things that conventional science is open to? Besides, we'll likely not get proof that ailens exist, at least in the US, because US Federal law prohibits contact with non-Terrestrial beings! As for the links, it would probably not make it past consensus and into an article, at least the whole thing anyway. Why? It's not a frindge theory because it's not a purely scientific article. Anyway, are there any articles that this information might be helpful to? Thanks. ~AH1^(TCU) 18:10, 3 May 2008 (UTC)

The problem isn't so much the lack of evidence as it is the lack of more evidence for one explanation over another. Sure, you could explain UFOs are alien spacecraft, but you could also explain them as some unknown meteorological phenomenon, or a test of classified military technology, or any number of other things. There's no more evidence for it being aliens than for any of the other wild guesses. --Tango (talk) 20:25, 3 May 2008 (UTC)

I find Bertrand Russell's Last Thursday theory of creation to be the most intellectually satisfying of the lot. It explains everything except the moment of creation, and does not contradict with anything. Even science cannot do that. Imagine Reason (talk) 16:59, 4 May 2008 (UTC)

I can see what you mean. Perhaps the last sentence there is more correct than the first. Imagine Reason (talk) 18:12, 3 May 2008 (UTC)

Scientists have a hard time accepting the 'evidence' for UFOs (and religion) because you have to assume the existence of extraterrestrial aliens (and god/gods) for the case for UFO (and religion) to make the argument. Scientists are willing to accept the hypothesis, but not make unwarranted assumptions. -- JSBillings 18:17, 3 May 2008 (UTC)

It is hard to accept UFO's as being alien spacecraft not because it requires aliens to exist, but it requires aliens to be capable of interstellar travel. Most scientists will probably believe, based purely on statistics, that lifeforms (however intelligent) exist somewhere else in the universe.--Shniken1 (talk) 13:28, 4 May 2008 (UTC)

The sauce on the Flying Spagetti Monster had the same DNA as Invisible Pink Unicorn blood,may her hooves never be shod.hotclaws 23:29, 8 May 2008 (UTC)

mechanical nasal congestion relief

This question has been removed. Per the reference desk guidelines, the reference desk is not an appropriate place to request medical, legal or other professional advice, including any kind of medical diagnosis, prognosis, or treatment recommendations. For such advice, please see a qualified professional. If you don't believe this is such a request, please explain what you meant to ask, either here or on the Reference Desk's talk page.

This question has been removed. Per the reference desk guidelines, the reference desk is not an appropriate place to request medical, legal or other professional advice, including any kind of medical diagnosis or prognosis, or treatment recommendations. For such advice, please see a qualified professional. If you don't believe this is such a request, please explain what you meant to ask, either here or on the Reference Desk's talk page. --~~~~

We really can't advise you on how best to perform medical procedures on yourself, or how to acquire equipment for same. If you want to perform procedures on yourself, you should speak to an appropriate specialist first—you need to be trained in proper methods, risks, choice of equipment, and so forth. It may not be appropriate for you to attempt the procedure without supervision, period. TenOfAllTrades(talk) 15:03, 3 May 2008 (UTC)

Self operation

Talking of carrying out procedures on yourself, I recall a report of a surgeon who tried to remove his own appendix. Failed in the attempt when he passed into unconciousness. Anyone got a link to this event? It was maybe 25 years ago, so I could be going senile and imagining it. SpinningSpark 16:27, 3 May 2008 (UTC)

The surgeon you are referring to is Dr. Kane, and i've found one link that documents the event: http://query.nytimes.com/gst/abstract.html?res=9F03E0D9123CE533A25754C1A9649C946095D6CF Regards, CycloneNimrod^Talk? 18:10, 3 May 2008 (UTC)

Wikipedia has an article on almost everything, but not on Dr. Evan O'Neill Kane, though there is an article on his father, and Dr. Evan's remarkable feat is mentioned in the article on Kane, Pennsylvania. ---Sluzzelin talk 18:57, 3 May 2008 (UTC)

That was in 1921? I must be older than I thought! SpinningSpark 22:49, 3 May 2008 (UTC)

We do, however, have an article about Dr. Jerri Nielsen. 146.115.120.4 (talk) 20:52, 3 May 2008 (UTC)

...which references the own-appendix-removal feat of Dr. Leonid Rogozov, which we don't have any article on either. We seem to have discovered a rare void in Wikipedia coverage. --169.230.94.28 (talk) 18:59, 8 May 2008 (UTC)

gravity within a heavy body (Earth)

Approximately what happens to measurements of gravity going deeper toward the center of the earth (ie: increase to 2Gs at 1000 miles deep, then progressively decrease to 1G at 2000 miles and to zero Gs at the center)? —Preceding unsigned comment added by 70.157.224.152 (talk) 19:06, 3 May 2008 (UTC)

For a body of uniform mass distribution (ie. the same density all the way through), it decreases linearly to 0 at the centre (so 1g on the surface, 0.9g 10% of the way down, 0.5g half way to the centre, etc.). The Earth isn't actually uniform, so that won't quite work, but it's still going to reduce all the way down, just not at a constant rate. It will never increase when you go deeper. --Tango (talk) 19:25, 3 May 2008 (UTC)

Actually I think it does increase as you go deeper until you hit the outer core. The core is so much denser than the mantle that increasing proximity to the core outweighs (literally) the reduced influence from the mantle. -- BenRG (talk) 21:13, 3 May 2008 (UTC)

I hadn't thought of that - you're right. Based on some very rough calculations, gravity at the edge of the outer core could be around 25% higher than on the surface. You learn something every day. --Tango (talk) 21:41, 3 May 2008 (UTC)

My rough calculations disagree. Care to share yours? Dragons flight (talk) 03:30, 4 May 2008 (UTC)

It's probably the numbers rather than the calculations that differ. I was using an core radius of 3400km and a density of 13000kg/m³ (that's an very rough upper limit given the data I could find) and the whole Earth with a radius of 6371km and average density of 5515kg/m³. I then used that acceleration due to gravity is proportional to density times radius (I ignored the constants, since I was just interested in which was bigger). That gave gravity at the core being 4.42x10¹⁰ and gravity at the surface being 3.51x10¹⁰ in whatever strange units that comes out to. --Tango (talk) 12:58, 4 May 2008 (UTC)

I'm sure there is some way of finding this answer by searching the archives. The idea is encapsulated in the Divergence theorem, otherwise known (especially in physics), as Gauss's Law. Note that I've linked to the form you should find especially useful. (The most common meaning when people refer to Gauss's law is to the electric field. Since both electricity and gravity are conservative forces following an inverse square law, they obey much of the same mathematics.)

The idea behind applying the mathematics is that at any point inside the surface of the earth, there is a big spherical chunck of earth "below" you and a big spherical shell of earth "above" you. The math proves that the shell actually doesn't have any effect on your measurements of gravity. Once you know that, you can reason that as you move away from the center of the earth, the mass "below" you grows cubicly; however, your distance from the center falls linearly, so the gravitational strength falls quadradically. Therefore, the total measurment of gravitational force increases only linearly.

To really understand it, you should work out the mathematics for yourself. For a more detailed explanaiton, you should indicate what level of mathematics you can (or want to) deal with. — gogobera (talk) 19:40, 3 May 2008 (UTC)

Just to say on Gauss's law, an historical note, I believe that it was Newton who first showed that there is no field inside a hollow sphere. SpinningSpark 23:52, 3 May 2008 (UTC)

Yes, he did it with the shell theorem, a far more complicated way of doing it than with Gauss's law of gravity, which renders the problem trivial. Someguy1221 (talk) 03:32, 4 May 2008 (UTC)

Science in crisis ?

Recently, I have been reading statements from leaders in the scientific community, philosophers of science, university professors, sociologists of science, corporations who hire scientists and scientists themselves, and many claim that there are wide problems within science that go from methododogy, to financing, to training sufficient specialists and to the very goals of science itself.

• Author Paul Feyerabend embraced relativism, and even "epistemological anarchy".
• Thomas Kuhn's philosophy of science, as expressed in The Structure of Scientific claims that as well as progressing steadily and incrementally ("normal science"), science undergoes periodic revolutions or "paradigm shifts", leaving scientists working in different paradigms with difficulty in even communicating.
• According to Daniel Boy, researcher at CNRS, there is a major european shortage of qualified scientists and mathematicians. `[8]
• The blog Science Crisis gives many details on the so-called scientific crisis. [9]

What are the social, political and technical consequences of such a phenomenon ? 69.157.243.164 (talk) 20:00, 3 May 2008 (UTC)

I'm not sure this reference desk is really suited to such a philosophical question. The best we can do is offer our personal opinions, and what good is that, really? We're just random people on the internet. --Tango (talk) 20:21, 3 May 2008 (UTC)

Things like statistics on students graduating in certain fields, science spending etc. can be found from sources like the EU, UNESCO and the like, or by googling. Opinions on the effects on certain fields can be found by searching journal sites, such as "Physics Today" for relevant key words. (They have e.g. some articles describing the effects of not building the Superconducting Supercollider.) A search through history pages for similar situations (or asking at th Humanities desk) should give some basis for evaluating the sources you cite. Apart from that Tango's right all we could offer would be anecdotes and opinions. --71.236.23.111 (talk) 22:23, 3 May 2008 (UTC)

Today's society generally undervalues scientific endevour. I blame society's current obsession with vacuous celebrities. When a large proportion of school kids are limiting their aspirations to "I want to be a celebrity like ...." why should they think science is a worthwhile career? Just look at the treatment of scientists in film - they're usually depicted as boring nerds or evil madmen. The kids of today don't want to be scientists when their friends will laugh at them and they won't get any hot dates. So what happens when the current generation of scientists retire? No wonder science is in crisis. Astronaut (talk) 16:10, 4 May 2008 (UTC)

I have to say, though, as a scientist who is only slightly mad and boring, I have had no trouble getting hot dates. This does not stop my friends from laughing at me. Nimur (talk) 16:29, 4 May 2008 (UTC)

Kevin Eggan made it into People Magazine's 100 sexiest men issue a few years back, hot dates has not been a problem for him. Rockpocket 19:03, 4 May 2008 (UTC)

I find that stereotype a strictly American phenomenon, one that has existed for a long, long time. Anti-intellectualism is embraced for many reasons here. Imagine Reason (talk) 02:49, 5 May 2008 (UTC)

Visual question

Why does the human eye do a far better job at handling the lighting contrasts in what it sees than cameras do? I guess this is because as humans evolved, the brain became increasingly more complex, and is in fact post-processing what the eye sees before, sort of, letting itself see it. But when we look at a photograph, the brain does not recognise it as a real live view, and does not know to post-process it. If this is right, then it feels very weird not seeing things as they really are, and having no way to change that. JIP | Talk 20:30, 3 May 2008 (UTC)

If everyone answered their own questions as well as you just did, we would have nothing to do here!

You might like to read the visual perception and optical illusions articles. --Anonymous, 22:13 UTC, May 3, 2008.

I was just proposing a theory and asking if it was right or wrong. It feels really weird that the brain is doing something which it, in effect, keeps secret from itself. But based on the theories presented in the article about visual perception, it is for the better, because otherwise we would not perhaps be even able to survive, not to mention enjoy the free time in our life. JIP | Talk 21:23, 3 May 2008 (UTC)

Could you give an example of what you are talking about?Em3ryguy (talk) 22:59, 3 May 2008 (UTC)

There have been a couple of research studies and experiments that tell us that, "the brain is doing something which it, in effect, keeps secret from itself," is much more the usual state of affairs than something unusual. Scientific American has split off an entire magazine because such questions have garnered so much interest. To mention just a few: pheromone and chemical cues from the olfactory system influence behavior[10], without entering conscious recognition. You can fool your body to mix sensations that would be generated by what it sees with those actually reported. [11] [12] [13]You might also enjoy http://www.rburton.com/work1.htm . Our Choice-supportive bias only touches on a huge area currently under study, there are probably a host of relevant pages I haven't seen, though. Lisa4edit (talk) 23:22, 3 May 2008 (UTC)

Yeah, I think the post-processing idea is right but there is also a mechanical reason. When a camera takes a picture, it must choose one iris setting and the picture is printed with one dynamic range of contrast (left as exercise for student to convert that sentence to modern electronic-speak). A human eye is not taking a single picture, but is constantly viewing a scene. Details in, say, a dark corner can be observed by opening up the iris and ramping up the gain - those details can then be added to the image already formed in the brain. In a bright corner, do the opposite, close down the iris and the gain. A camera cannot do that with a single snap resulting in "clipping" of either the dark or the bright detail. SpinningSpark 23:45, 3 May 2008 (UTC)

If we are talking picture there is also the color representation issue. Particularly green shades are devilishly difficult to generate. That's why some pictures have an "unreal" tint to them. Lisa4edit (talk) 00:12, 4 May 2008 (UTC)

Some other reasons:

• Point-and-shoot digital cameras have a lot of CCD noise because the CCD is small.
• JPEG only has 8 bits of luminance depth, and it's mapped roughly linearly to perceived brightness, so there's not much resolution at the dark end.
• Regardless of the camera's abilities, photographic prints and computer monitors can't reproduce anything close to the dynamic range of the real world. -- BenRG (talk) 13:00, 4 May 2008 (UTC)

When you look at a poor-contrast picture, one reason your eye can't "fix" the contrast the way it would have if it had been looking at the same low-contrast scene in real life is really: your eye is doing a good job. You did not show it that low-contrast scene and ask it what it looked like. Rather, you showed it that low-contrast picture and asked it what it looked like. And your eye is correctly telling you: "it's a low-contrast picture." If there are any details to be made out beneath the poor contrast in the picture, your eye will probably see them. But it won't stop telling you "But, by the way, the contrast is really bad." —Steve Summit (talk) 16:13, 4 May 2008 (UTC)

I assumed as much. When I look at a photograph, what my eyes see is not the original light, but the camera's captured image of it. Thus, the eye's constant scanning (as mentioned above) can not react to the difference in actual light in parts of the picture, because there is none. JIP | Talk 19:31, 5 May 2008 (UTC)

Although it is true that we recognize that photographs are only representations, it is absolutely untrue that no "post-processing" occurs in the brain. The post-processing you speak of is not (in general) the kind of post processing that a photographer accomplishes in photoshop. I can't articulate this very well, but although it seems as though your experience of sight is as though you were a homunculus observing a stereoptic film, the fact is that a significant portion of our experience of sight relies on interpretation of what we see. When you look at a photo, you don't see it as a live image, but you also don't see it as blobs of color: you see it as a photograph, with a background, foreground, objects, people, faces, etc. you are capable of interpreting many out-of-focus features, although your perception of these features does not bring them into focus as computer post-processing would. Your implied question of "seeing things the way they really are" is a serious topic in metaphysics and philosophy of mind. Whether there is an objective "how things really are" is even relatively contentious.--Shaggorama (talk) 09:13, 8 May 2008 (UTC)

Dry season

In the equatorial regions, there are only dry or wet seasons. But what about just around the equator? Would there still be distinct different seasons on both sides? Or would it be one season all the way through? Or perhaps both sides of the equator follows the same season? 99.226.39.245 (talk) 23:24, 3 May 2008 (UTC)

Unless I misread your question, this phrase from the article would answer that: On the equator, there are two wet and two dry seasons as the rain belt passes over twice a year, once moving north and once moving south. Lisa4edit (talk) 00:17, 4 May 2008 (UTC)

Well, I was refering to literally on the equator. 99.226.26.154 (talk) 04:40, 4 May 2008 (UTC)

That answer refers to weather literally on the equator. What's the problem? Algebraist 08:04, 4 May 2008 (UTC)

You may be interested in reading [14] (note you will have to click on the links at the top of this page to navigate as a next link seems to be missing) and [15] (yes it's about a specific period quite old but isn't far from the norm from a quick read through) & [16] which describe the climate in Malaysia. While Malaysia is north of the equator the weather isn't as simple as one wet and one dry season it varies depending on the geographical location (and therefore the surrounding terrain), and the wet season particularly on the east of Peninsular Malaysia is usually in October to March (see also Floods in Malaysia and Monsoon Cup) while your likely to think the opposite from the wikipedia articles Dry season and Wet season. Tropical weather can be I think a lot more difficult to understand then the 4 season temperate model (although even that is far from simple). You may also want to read Monsoon if you haven't already. Nil Einne (talk) 13:12, 4 May 2008 (UTC)