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September 13

Chemical terminology

What is the term used to describe a chemical species, that is practically unaffected by water between pH 0-14? For example, Na⁺, Ne, etc. That is, disregarding solvation shells, they do not spontaneously react with water to produce new species. HO⁻, NH₄⁺, etc. are not examples. Is the term 'unhydrolyzable'? Plasmic Physics (talk) 02:12, 13 September 2013 (UTC)

It sort of depends on how you define your terms. If you read Ligand, you find statements like "Metals and metalloids are bound to ligands in virtually all circumstances"; a "solvation shell" is just water molecules bound as ligands to the metal ions (though highly labile ligands). Some species will bond stronger to H⁺ ions and other will bond stronger to OH^-. Lewis bases (like ammonia) tend to do the former, while lewis acids (like Fe⁺³) tend to do the latter. By Le Chatelier's principle the fact that Lewis bases or acids will bond strongly to H⁺ or OH^- ions is what tips the equilibrium and changes the pH. Species which are neither Lewis acids or Lewis bases is what you are looking for. I'm not sure there is a word for that. --Jayron32 19:51, 13 September 2013 (UTC)

Oral masturbation question

I note that autofellatio is quite possible, and was curious if there had been any documented cases of women who could perform "autocunnilingus", or if it's even physiologically possible. — Crisco 1492 (talk) 07:14, 13 September 2013 (UTC)

Why not... You just need to be real flexible. ☯ Bonkers The Clown \(^_^)/ Nonsensical Babble ☯ 07:26, 13 September 2013 (UTC)

• I haven't really been able to find a reliable source for any of this. At most there are porn feeds, which are not necessarily scientifically accurate (I recall one which had a three-breasted woman, so it could be niche). Our article on oral sex mentions autocunnilingus, but no reference. — Crisco 1492 (talk) 07:31, 13 September 2013 (UTC)

These seem useful In theory it is possible, that is for certain. ☯ Bonkers The Clown \(^_^)/ Nonsensical Babble ☯ 07:35, 13 September 2013 (UTC)

• Dicdefs, mostly. This is the only one that is somewhat helpful, but that seems to be (non-human) primates. — Crisco 1492 (talk) 07:37, 13 September 2013 (UTC)

Here's a blog devoted to the topic discussing the possibility: [1]. In it they mention Zlata, we don't have an article on her, but here is her site: [2], two other pages about her: [3], [4] (it mentions something about her having some form of condition). Here's a video [5]of her doing a Frontbend to let you form your own opinion. Zlata aside, you may want to take a look at Contortion, Hypermobility, and Ehlers–Danlos syndrome, and a link to the Dutch Wiki on the matter: [6]. That's the most reliable bit of info I could find, the rest was just porn clips, which aren't too helpful.Phoenixia1177 (talk) 09:55, 13 September 2013 (UTC)

• That's interesting (noticed the Dutch Wikipedia article already). Thanks for the blog, didn't see that pop up in Google. — Crisco 1492 (talk) 11:10, 13 September 2013 (UTC)

Naegleria fowleri — what does it normally eat?

Piecing together various things I've heard, it seems that the spectacular, usually lethal, human infection is a dead end for the microbe, and not a reflection of its normal life cycle. A recent news article says that it's not truly an amoeba, but calls it a parasite; our article, on the other hand, says it's a "free-living protist", but that it's related to trypanosomes and to the organisms that cause leishmaniasis, which certainly are parasites.

So if it doesn't normally eat brains, then what? Does it have a facultative parasitic life path when the opportunity presents itself, one that's not a dead end? --Trovatore (talk) 09:10, 13 September 2013 (UTC)

It definitely has a "normal" life cycle that does not involve eating human brains. See this CDC page [7], with references to three recent science papers, all of which call it an Amoeba. Compare to Clostridium_tetani, which normally just hangs out in the soil doing bacteria things, but causes big problems if it gets inside right/wrong bits of a human body. The pathogenicity in both cases, is, to my knowledge, basically just bad luck, or perhaps an accident of history. SemanticMantis (talk) 13:14, 13 September 2013 (UTC)

Hmm, don't really buy the bit about tetanus. Elaborate high-molecular-weight peptide neurotoxins don't happen by chance. My guess is that C. tetani (and C. botulinum) kill animals so that their corpses provide a nice anaerobic growth medium. --Trovatore (talk) 19:17, 13 September 2013 (UTC)

Synthesizing elements 119 and 120

Why hasn't it succeeded yet? Theoretical studies indicate that we should be capable of doing this already, and indeed experiments have already been started. Why have they all failed? The half-lives predicted are long enough that the resultant atoms should survive the journey to the detector. And why can't we just keep using ⁴⁸Ca projectiles on Es for element 119 at least? Double sharp (talk) 11:53, 13 September 2013 (UTC)

We have articles on Ununennium and Unbinilium - in both cases, about half of the possible routes to synthesis have been tried - but simply failed - and not for any well-understood reasons. Using ⁴⁸Ca projectiles on Es has been tried, and failed to produce a single atom...so unless there is credible reason to suppose that the superHILAC team at Berkeley screwed up, experimenters are going to want to try the other predicted synthesis route just because it has a higher chance of succeeding. There might even be some actual successes - but the results have not been announced, so the teams may be waiting for confirmation or something. Element 120 is a more promising target than 119 because it's predicted to like on the island of stability - and because there are many more routes to synthesis to explore. SteveBaker (talk) 15:27, 13 September 2013 (UTC)

A credible reason might be that it's very old results (1985!)? This paper thinks that the ²⁵⁴Es reaction should be about as effective as the reactions that made elements 117 and 118: if that's the case, then why not do that? It seems the only obstacle is getting enough of it!

(Just realized this possibility: Maybe the isotopes are less long-lived than we previously thought and hence we are making them, but they are decaying before they reach the detector. Is there some way to increase detector efficiency and beam intensity by at least an order of magnitude?) Double sharp (talk) 04:11, 14 September 2013 (UTC)

Kidney bruising

How do most kidney bruises occur? It seems to be common in footballers but how much force is required? Wouldn't fat and muscle protect it unless it was a very strong force? Can kidney bruising be seen? Clover345 (talk) 14:51, 13 September 2013 (UTC)

Your kidneys are generally well protected by muscles of the back and rib cage but injuries can occur as a result of blunt or penetrating trauma. (Urology Care Foundation [8]). Most Kidney injuries occur from blunt force due to motor vehicle accidents, falls, or sports injuries. The kidney is actually injured more often than any other organ along the urinary tract..(The Merck Manual Home Health Handbook [9]) A bruised kidney is characterized by bleeding within the kidney.(The Livestrong Foundation[10]). The bruise cannot be seen, but blood in the urine is an important indicator of a kidney injury. Pain in the upper abdomen and flank are further indicators of a kidney injury. Ljtr222 (talk) 19:17, 13 September 2013 (UTC)

Ljtr222 I have taken the liberty of re-formatting your references to make them available to readers without a 'references' template. (they all had <ref name="test"> which is unnecessary, in fact undesireable as it gives all your refs the same ref name--220 of ^Borg 19:40, 13 September 2013 (UTC)

Physiology behind eating certain types of food

Is there a scientific consensus on what causes the rejection of certain non-meat types of food (like onion, garlic, scallion, mushrooms, olives)? I've recently found that I can't stand cooked zucchini, as well as eggplant, which while in mouth trigger vomiting in me, whereas all other members of my family eat them. Is it something different from food intolerance like lactose intolerance?--93.174.25.12 (talk) 17:27, 13 September 2013 (UTC)

I strongly suspect that this isn't a chemical intolerance like lactose intolerance - but a psychological matter. However, we're not allowed to give medical advice here - so we can't discuss your personal situation. SteveBaker (talk) 17:33, 13 September 2013 (UTC)

It is well known that if you have been vomiting after eating some food with a non neutral taste, this can cause your brain to flag that taste as disgusting later. Patients on chemotherapy are adviced not to eat their favorite food during the time they experience nausea. Count Iblis (talk) 17:44, 13 September 2013 (UTC)

You might be interested in reading what we have at selective eating disorder. SemanticMantis (talk) 18:12, 13 September 2013 (UTC)

The negative conditioning model is a good potential explanation, yet... it surely doesn't cover everything. For example, I never encountered durian in any form until one day, well into adulthood, I encountered a container of durian-flavored cookies left in a lunchroom as an exhibit. I was blissfully ignorant of what to expect, yet, O-my-God is that repulsive, like cannot be believed, merely to smell from a distance! The weird part was that I kept sniffing at the bag at intervals, racing to the sink out of fear of an incident, then trying again, because the scent is such as cannot be remembered a minute after it is smelled ... indeed, it is almost as if it cannot be experienced even as it is perceived. Memory cannot contain it. I can only recall how I reacted to it. Wnt (talk) 21:55, 13 September 2013 (UTC)

What happens when you place a Crane Fly in Sulfuric acid?

If I was to place a live crane fly in a bottle of sulfuric acid, can I have a basic scientific explaination to what would happen to the crane fly? Would it die painfully? --LiebeisBesser (talk) 19:11, 13 September 2013 (UTC)

Depending on your definition of pain, yes or no. See Pain in invertebrates for some of the controversy surrounding whether invertebrates feel pain as we understand it. It's probably not the best idea to gratuitiously kill just to see what happens, regardless of whether it can or cannot feel pain; experiments on animals are also controversial, but should only be properly carried out under they auspices of a proper governing body who maintains ethical standards for animal experimentation; you just screwing around and seeing what happens is not under such a governing body. --Jayron32 19:17, 13 September 2013 (UTC)

It's hard to know whether such primitive animals experience pain per-se. Also, the fate of the beast will depend entirely on the concentration of the acid. So-called "acid rain" is weak sulfuric acid - and crane flys seem to survive that OK. In concentrated acid, they'd doubtless die very quickly because the acid will dissolve most (if not all) of their tissues. SteveBaker (talk) 19:19, 13 September 2013 (UTC)

Why would you want to torture a crane fly, or any other living thing? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:09, 13 September 2013 (UTC)

This was my reaction as well. What is you specific curiosity here: the experience of pains in flies, the effect of acid on living things, or something else entirely?Phoenixia1177 (talk) 21:26, 13 September 2013 (UTC)

The moralism here is laughable, and may well deserve a separate Humanities thread. Either it is good to put up flypaper to kill hundreds of flies, spray insecticide on a farm to kill millions, or it is bad. Either way one fly in sulfuric acid does not matter. You act as if it is only ethical to kill something if you do it with your eyes shut. I suppose I know why - because there is rampant infection with brood parasites, dubbed "pets", which have evolved to fill a fantasy that they are human children, and people desperately contort their theories to match their infestation. Sometimes it is pretty clearly science itself that is regarded as wrong - for example, to kill a mouse horribly in a snap trap or starving in glue is everyday home maintenance, but the slightest mistreatment for the sake of curing cancer is severely punishable. (Perhaps the moral is that it is wrong to cure cancer)

As for the question, it is not so simple to figure out from first principles. Insects can survive a few minutes in vacuum, much of an hour underwater, you can clean their eggs with a fairly concentrated bleach solution, etc. They are evolved to survive extremely dry conditions despite an absurdly high surface-to-volume ratio. Nonetheless, chitin, despite being one of the most resistant biomolecules to degradation, will succumb to concentrated acid, releasing oligosaccharides. [11] So you can indeed punch holes through the exoskeleton, with ordinary protein and other components succumbing to the acid just as they do in a human. Wnt (talk) 21:44, 13 September 2013 (UTC)

I think the "moralistic" impulse in the responses is not so much about some particular crane fly suffering, as it is in response to the idea that the OP might be specifically wanting to cause suffering in a crane fly. Of course we don't actually know whether the OP wants that, or even enjoys thinking about it, but if he/she did, then it's a natural response to wonder why, and to try to discourage wanting such a thing.

What came to my mind was, why a crane fly, specifically? They're almost totally inoffensive, except for being sorta ugly, but they probably don't think I'm pretty, either. If it were a mosquito I would understand (not exactly approve, but I'd have to admit that the impulse was not exactly foreign to me). --Trovatore (talk) 08:08, 14 September 2013 (UTC)

Thanks for the second paragraph, It's a good, referenced answer. No need for the initial diatribe though. I don't want to spiral into a needless debate here, so I'll try to head that off by weighing in in the middle.

Jayron's response wasn't exactly condemning all insect death, and he gave some good refs. Indeed there are and have been some animal experiments that I wouldn't want to approve, and I do generally support the aims of Institutional_review_boards for human and animal experimentation. However, it's also a too broad to say that animal experiments are always controversial. We kill all kinds of flies, bees and ants everyday in the name of science, and that research is seldom attacked on ethical grounds.

Finally, the article above clearly states that pain in invertebrates is contentious and problematic. My WP:OR suggests that very few practicing entomologists have any qualms about it. If the OP has specific questions about what "pain" might exist in the insect experience, s/he should ask another question.

p.s. Calling pets a "rampant infection with brood parasites" did make me laugh :) SemanticMantis (talk) 22:10, 13 September 2013 (UTC)

What now? I didn't realize I used mouse traps in my house, nor was I aware that being bothered by the possibility of arbitrary pain in a fly had something to do with my feelings on cancer research (both, obviously, yield the same amount of useful results). You seem to be making a lot of assumptions to reach your conclusion for a "defender" of science.Phoenixia1177 (talk) 21:54, 13 September 2013 (UTC)

For the part about the mice I was referring to this sort of 'claptrap'. [12] Wnt (talk) 22:14, 13 September 2013 (UTC)

I'm very sleepy and am not sure who is addressing who- that said, I think if there is no useful purpose to something that can potentially inflict pain, then that something should not be done. It makes me sad knowing that mice die for research, but feeling sad is not inconsistent with supporting such research out of necessity. I don't think anyone here has raised an objection to cancer research, at most the objection is to an image of the op pointlessly dropping various living things in acid for the hell of it (whether that's their interest, or not).Phoenixia1177 (talk) 22:23, 13 September 2013 (UTC)

Simulating the brain of insects is a task than can in principle be executed by modern PCs, so if we assume computationalism, insects being able to feel pain would imply that using your PC could lead to pain being felt by some program it executes. Count Iblis (talk) 23:18, 13 September 2013 (UTC)

Interesting assertion. (this is why I refrain from powerpoint) SemanticMantis (talk) 23:37, 13 September 2013 (UTC)

Which is, in and of itself, virtually a complete refutation of computationalism. --Trovatore (talk) 07:47, 14 September 2013 (UTC)

Not really, the computer doesn't have all of the other biochemical pathways that are implicated in pain. Also, while computers are beginning to have the same computational complexity as an insect brain, they aren't organized the same way with all of the nerve endings and such that transmit pain to the brain and all of the physical processes that go on besides. We would need a more comprehensive simulation of the entire insect to produce this kind of effect. But it's not inconceivable that a computer program could "feel pain" in the way that (we believe) some or perhaps all non-human animals can. But this is never going to be an easy question - we can't decide whether insects feel pain - so how could we decide whether a computer simulation of one does? SteveBaker (talk) 12:53, 14 September 2013 (UTC)

I believe that considering "computer pain" would make it a lot easier to solve this problem, because it would force people to consider the problem in terms of well defined concepts. So, what matters is the computational state of a system; there is some the set of systems that are capable of perceiving pain, but algorithms executed by these systems can be totally different. Therefore, pain must be a universal phenomena. It will probably eventually be understood in terms of the world as perceived by some algorithm, pain obviously must have something to do with the discord between what the algorithm itself says it wants to do (which is an objective thing as it can be extracted from the information encoded in the algorithm) compared to what it actually is capable of doing under the circumstances it finds itself in. Count Iblis (talk) 14:09, 14 September 2013 (UTC)

There is no way to define qualia in terms of externally observable anything. They are inherently subjective (yet objectively real). No, the computational state is not what matters. I think that's just absurd on its face. --Trovatore (talk) 19:01, 14 September 2013 (UTC)

Yet, according to quantum mechanics, the exact physical state of a system can be specified by specifying the eigenvalues of a complete set of commuting observables. So, if I have Trovatore in an isolated box, whatever you experience must be describable in terms of a suitable set of Hermitian operators. Count Iblis (talk) 23:14, 14 September 2013 (UTC)

Your mistake is that you assume I'm a physical system. --Trovatore (talk) 01:33, 15 September 2013 (UTC)

Good point. You could be an Organian, or one of their cousins. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:43, 15 September 2013 (UTC)

No, my body is a physical system. That's different from saying I am. --Trovatore (talk) 02:59, 15 September 2013 (UTC)

I would argue (but this is rather controversial) that in the formalism of quantum mechanics, the complete set of Hermitian operators for a system should in general refer to the qualia the system can experience. If Trovatore measures the z-component of the spin of an electron that is polarized in the x-direction, his state after performing the measurement is 1/sqrt(2) [|Trovatore measures spin up>|up> + |Trovatore measures spin down|down>] The measurement problem in quantum mechanics is solved by talking into account that any measurement involves experiencing qualia and these must define a preferred basis. So, there exist qualia for experiencing things that when put toghether point to the measurement outcome being spin up or spin down. The totality of available observables for Trovatore must correspond to precisely what Trovatore can subjectively experience (besides knowing what the outcome of the measurement was, you can also have pain in your knee and experience the taste of your lunch). Count Iblis (talk) 14:07, 15 September 2013 (UTC)

So you think that, say, hydrogen atoms must have qualia? I can't prove they don't, of course. But it seems bizarre to me to assume they do. --Trovatore (talk) 18:15, 15 September 2013 (UTC)

Perhaps, but the system has no degrees of freedom when in the ground state (or two (qu)bits if you consider the spin of the proton and electron). I think some of the philosphical objections can be addressed by carefully considering a system that needs to be described by an astronomically large number of bits. Then consider what I said above about the system observing itself, the qualia won't form a "complete set" in the sense that what you experience won't pin down your exact physical state, there will be a huge degeneracy. You can never know exactly what state you are in, as the amount of information required for that would never fit in your available memory. But then, if you accept the Many Worlds Interpretation (MWI) of quantum mechanics, this means that you should always think of yourself as smeared out over some astronomically large number of macroscopically similar states.

Such a set of states contains information about the time evolution of the system, e.g. that you did something in response to something else implies that there is non trivial causation. This then addresses a well known thought experiment where one imagines replacing neurons by transitors and then one says that since the output to the actual input was what it was, you can replace the transitor by a fake transitor that always has that output and then the qualia would have to remain the same. That would seem to imply that a static representation of your brain would have your consciousness. Obviously, this argument fails in the MWI picture because you do have counterfactual states inside that large group of states over which you are smeared out. So the information that you would have done something slightly differently had the input been slightly different, is present in the set of states.

So, I believe that there is room within quantum mechanics to deal with some of the objections against computationalism (but without invoking non-classical quantum phenomena). Count Iblis (talk) 19:33, 15 September 2013 (UTC)

@Wnt above, there's a huge difference between killing out of necessity pest insects which have invaded your house and torturing to death a harmless non-pest. Admittedly, it is an abstract distinction that requires the self-control not to swat at and the discrimination to differentiate between harmless and harmfull critters. Surely as empathetic adults that's not above us. Or are we all trolls? μηδείς (talk) 22:06, 14 September 2013 (UTC)

It gives one pleasure to have a house free of the buzz of flies; it gives one pleasure to investigate the rough science of flies in acid. Difference? Jainism is thataway. Wnt (talk) 22:39, 14 September 2013 (UTC)

No, there is no sadistic pleasure to mature adults in killing flies. They are disease-spreading pests that have evolved to plague and feed upon us. We don't kill them by slowly dissolving them. A crane fly is a harmless accidental visitor. Given the amount of advice you dispense I would be shocked to find you don't understand the difference. Or maybe you enjoy feigning ignorance, which tells us about you as well. μηδείς (talk) 22:57, 14 September 2013 (UTC)

You're categorizing someone else's pleasure as sadistic or not. Moreover, you're telling me there's no "sadistic" pleasure in swatting a fly that's been buzzing around the room? Really? And that it must be sadistic to experiment with a crane fly in acid? Really? I'd think the former might be more "sadistic" than the latter.

I suppose there's a broader issue here: this notion that it's OK to do anything unless you take pleasure in it. Ever since the bland functionaries of the Holocaust I don't think that kind of reasoning should fly. If harming an insect were unethical it should be unethical whether you do it out of sadistic glee or in order to get an extra dollar an acre out of farmland. Wnt (talk) 14:40, 17 September 2013 (UTC)

Underground stream of water

Is there a name for an underground stream of water which emerges in times of rain (and forms pools of water)?

To be more specific: in the Sand River in St Francis Bay, South Africa water flows underground, over a hard rocky substrate that underlines the dunes. The water emerges in times of rain, when the river stops flowing a number of pools of water remain.

I was just wondering what this phenomenon is called. Servien (talk) 20:06, 13 September 2013 (UTC)

An underground stream that emerges from the ground is called a spring. See Spring (hydrology). --Jayron32 20:18, 13 September 2013 (UTC)

Losing stream, subterranean river, and wadi might be useful articles, but I don't think there's a specific name for a river that is normally underground but rises above ground occasionally. Rivers which dry out completely for most of the year (such as the Todd River in Australia) are called "ephemeral rivers", but the river type you describe would always have a flow of water, even though it's not usually visible. (Incidentally, we have articles on four Sand Rivers in South Africa, but not the one you mention. Is it part of a larger system?) Tevildo (talk) 20:22, 13 September 2013 (UTC)

My favorite is the intermittent Mojave River. It's always running underground except for a couple of year-round surface flows, but it's above ground when there's enough rain. --jpgordon^{::==( o )} 22:08, 13 September 2013 (UTC)

I also found Lost River (Indiana). Alansplodge (talk) 09:51, 14 September 2013 (UTC)

Several streams or stream courses mostly in the south-west of England are called "Winterbourne" as all or part of their name because they generally only ran in the wetter winter season. Annual variations, more gradual climate changes, and alteration of water tables by artificial extraction may have affected this one way or another, so now some may run permanently while some others may be permanently dry. {The poster formerly known as 87.81.230.195} 90.213.83.178 (talk) 22:45, 15 September 2013 (UTC)

Thanks for your responses. Quite weird that there is no name for such a river/stream, since the term spring doesn't quite cover it. It is not part of a larger system as far as I know, there are no nearby rivers where the water could come from or run to. I've added it to the Sand River disambiguation page. Servien (talk) 17:41, 17 September 2013 (UTC)

wireless keyboards/mice

hello, I'm probably not the first one to whom this idea has occured and who wonders if it's true, but are (non-Bluetooth) keyboards and mice, on the physical level, actually Bluetooth systems where the transmitter (you know that tiny thingummy that goes into the USB port) and the device have been pre-"paired" in advance and the computer interface of the dongle modified so that the operating system sees a keyboard/mouse rather than a generic Bluetooth module? I mean, both types of devices (BT and non-BT) transmit at 2.4 GHz, the dongles look the same, so can't the hardware manufacturers have "reused" parts of the BT physical protocol (along with the respective circuitry)? Asmrulz (talk) 23:30, 13 September 2013 (UTC)

September 14

Solar eclipse

Here's a question I've been meaning to ask for a long time: When I watched the annular solar eclipse two years ago, I saw many people try to watch it through ordinary sunglasses (which, as you probably know, are completely inadequate for this task). Which got me wondering: Is there usually a local increase in eye-related complaints immediately after a solar eclipse? (No, this is not medical advice -- I used welding goggles, so I had no eye problems afterward.) 24.23.196.85 (talk) 00:39, 14 September 2013 (UTC)

Solar eclipses aren't annular, they occur far less often than once a year. μηδείς (talk) 01:26, 14 September 2013 (UTC)

"Annular eclipse" is a type of partial eclipse where all of the Moon is covering the Sun, yet the Sun isn't covered 100%, there is an annulus around the Moon that is not covered by the Moon. Count Iblis (talk) 01:51, 14 September 2013 (UTC)

(I think Medis is thinking "annual" rather than "annular" - but annular eclipses do happen at roughly yearly intervals at some place in the world - they aren't that rare. This site lists annular eclipses in 2012, 2013 and 2014 - but none in 2011 and 2015.)

This site has reports from hospitals in the area of eclipses (it's not clear whether they were annular - but the damage likely occurs before the eclipse gets to the annular stage - so the results are probably similar for less-than-total eclipses. They found 45 eye injuries in one case and 58 in another - in each case at just one hospital. So we'd have to guess that the overall damage in the path of the eclipse is probably in the hundreds of people. It seems that roughly half of the people who showed up at the hospital eventually recovered fully - while the remainder were still seeing ghostly after-images at least 15 years after viewing the eclipse. But much will depend on the educational and technological level of the people in the path of the eclipse. In a modern society, with comprehensive news coverage - people should be aware of the dangers - but out in the back-of-beyond, when the eclipse just suddenly and unexpectedly happens - I'd expect the number of victims to be vastly higher. SteveBaker (talk) 02:33, 14 September 2013 (UTC)

Medeis might be making a punny funny. "Annular" means ring-shaped. "Annual" means yearly. Given that a year is a "ring" of sorts (i.e. a "cycle"), it's tempting to try to link the terms together, but according to EO they come from different roots. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:53, 14 September 2013 (UTC)

Hmm, I hadn't thought of that. I read it and thought she was serious, and I was pretty surprised. I have to remember to use <small> for jokes even if I think it's obvious I'm joking; someone else might not be sure. --Trovatore (talk) 07:50, 14 September 2013 (UTC)

This is precisely why we ask people to refrain from joking until at least one decent answer has been provided - and to use the small font when you do. Medis is well aware of this - I think it was probably just a mis-reading of the question. SteveBaker (talk) 12:43, 14 September 2013 (UTC)

I am sorry, I simply couldn't resist. I'll hat this section. μηδείς (talk) 17:02, 14 September 2013 (UTC)

See also "Eclipse eye damage reports rise" news item following the last total eclipse visible in the UK in 1999. I expect it could have been much worse as there was full cloud cover over much of the country. Alansplodge (talk) 08:01, 14 September 2013 (UTC)

Although it turned out that there were only 14 actual cases of solar retinopathy in the UK following the 1999 eclipse, according to UK hospitals assess eye damage after solar eclipse published in the British Medical Journal; "In one of the more serious cases the patient had reportedly looked at the sun for around 20 minutes without protection". There's no accounting for stupidity. Alansplodge (talk) 09:44, 14 September 2013 (UTC)

Bad eyesight question

A guy in my programming class has to hold his cell phone within about 3" of his eyes for him to see it. He squints quite a bit when he does it. He also has some sort of tech assistance as well because as I saw him using it, it had large icons and only displayed part of the desktop on the screen at any point. He had to move the desktop around with his thumbs to choose various icons. Yet he watches my teacher lecture just as I do, i.e. with no visible impairment. I don't know if he wears contact lenses but he doesn't wear glasses. I have 20/20 vision and have never taken a big interest in various sight issues but I'm curious as to what may be the issue with this guy's eyes. Could it be any of a large number of things or what? Note: This is not a request for medical advice, I don't plan on treating this guy, I'm not planning on harvesting his eyes for some cruel medical experiment, I am not talking about "my friend" when I actually mean myself, I'm just curious. That's it. Thanks, Dismas|^(talk) 02:25, 14 September 2013 (UTC)

Have you asked him? He might be just watching the blob that the teacher looks like to him. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:47, 14 September 2013 (UTC)

Nope. I don't know him. Too much of an introvert to just ask some dude why he squints at his phone. Dismas|^(talk) 03:41, 14 September 2013 (UTC)

He could well just have limited vision. As long as he can hear the lecturer, and knows the convention of the "paying attention" body language, he will be looking at him in the same way that you would, but possibly not actually seeing much at all. If an image is up close, he might be able to see some it, and thus the squint at the enlarged phone screen. You could always just ask him if you can help with anything; you might learn something specific that way. Bielle (talk) 04:41, 14 September 2013 (UTC)

Does he seem to be able to get around otherwise? Any trouble finding his way in or out of the room, or the desk? ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:39, 14 September 2013 (UTC)

Consider the size of a human compared to the size of text or icons, and the different importance in distinguishing small details. I'm nearsighted (astigmatism), and if I can't tell a "j" from a "b" or "k", it's worth squinting for, if I care to read it. But it's not vital to see a teacher's pupils or whiskers to listen along and follow the blurry-yet-still-obvious human shape across a black (or white) board. InedibleHulk (talk) 07:06, 14 September 2013 (UTC)

See Visual acuity for our relevant article. Incidentally, "20/20" is not perfect vision, it just means you don't need glasses. Normal human visual acuity is around 20/16 to 20/12. Tevildo (talk) 11:30, 14 September 2013 (UTC)

Hyperopia ("long-sightedness", aka "far-sightedness") means that you can focus on distant objects with ease - but cannot focus on things close up without appropriate vision correction. If this person has the wrong prescription of glasses or contacts - or simply doesn't own such things - then what you describe is precisely the results you'd expect. I'm sure there are other possibilities - including that his vision is bad at all ranges but simply manages to cope with everything being out of focus at all ranges - but I'm fairly sure you'd have noticed that. SteveBaker (talk) 12:40, 14 September 2013 (UTC)

I see people do this all the time. My wife uses her iPhone like that on many occasions, for example. Vision can be a tricky thing; just consider the folks who need glasses, but don't have them, or need bifocals, but only have regulars, or need trifocals, but only have bifocals. While the text on a phone can be quite bright and sharp, it's very small, to the point where looking at it (even with glasses on) can be difficult if you're not at exactly the right length. This chap might have contact lenses to correct his long distance vision, but those lenses now make his up-close vision worse . Matt Deres (talk) 13:50, 14 September 2013 (UTC)

Another problem that even people with perfect vision have is that primary colors are focussed at different depths due to the fact that the lens of our eyes has different refractive indices at different wavelengths. For "normal" objects, there is rarely a pure color - so you can get a sufficiently sharp image despite that. However, on synthetic displays - and particularly with icons and other GUI elements - designers use a lot of 100% saturated colors. When they do that, the closely adjacent blocks of violently different colors defeat the eye's "autofocus" capability and the result is a blurry image. This effect is much worse when the display is close to your eyes - which is more often the case with cellphones than with other kinds of display. Designers for those systems would be better off using pastels and earth-tones rather than bright primaries...but they are continually fighting the problem that in bright sunlight, the displays get very washed out - and pushing the contrast higher helps that...hence they use a lot of primary color. As cellphone and tablet displays get brighter, hopefully we can return to a more muted color palette and life will be easier! SteveBaker (talk) 14:56, 14 September 2013 (UTC)

That's very interesting; I wasn't aware of the cause of that phenomenon with the contrasting primary colours. I experience that sometimes, especially with bright blue and red, where the blue lettering, say, will appear to dance and judder on the page. Used to get it all the time with the covers of colouring books when I was a lad. Would you get the same problem using black/white contrast instead? That would increase the contrast and would use rods rather than cones. Matt Deres (talk) 15:05, 14 September 2013 (UTC)

Blue and Red (being at opposite ends of the spectrum) produce the strongest effect - I'm quite sure that's what you're seeing. With black and white, the various frequencies that make up white are focussed at different depths, but somehow our brains compensate for that - but with pure red and blue, (which is something that just doesn't come up in nature) - we don't seem able to handle it. SteveBaker (talk) 18:09, 14 September 2013 (UTC)

It may be interesting. It would be even more interesting if anything Steve said was correct. He's got it horribly wrong. While the human eys optical system does have some chromatic aberation, as the difference is focal length for different colours is termed, it's not too bad, and due to the way the retina-brain system works, it is quite unimportant. It is quite unimportant for basically two reasons: we do not see detail in colour, and the brain is able to compensate for chromatic aberation, as explained below.

The human vision system gets its fine detail from the total light intensity, not from any one colour. When analog TV was developed, this was taken advantage of - analog TV works by transmitting a high resolution black and white image (termed "luminance") and a low resolution image in each of red, green, and blue primary colours, all 4 of which are added together in the TV receiver to reconstruct the composite colour picture.

When you look at a black object on a white background, you can see sharp edges because the eye/brain system works on the total light instensity change on the whiete/black transistion. When you look at (say) a pure red object on a black background, you still see the sharp eges, because the eye doesn't care whether its red or green or purple, it's working on the intensity edges.

The retina is most sensitive to wavelengths in the middle of the visual range. So wavelengths at the colour extremes don't contribute much in a composite image to the intensity as decoded by the retina.

Colour aberation can cause coloured lines to be displaced slighly on the retina. From this you would expect to see a thin white line on a black background as a red and green line next to each other. However the brain automatically compensates and re-merges the lines. It can do this because for any given eye, the compensation required is constant for any given object distance. And the brain knows the distance.

The eye/brain system's "autofocus" works by adjusting for the sharpest edges - the sharpest perceived intensity edges - with considerable "pre-tuning" from the object distance which the brain is able to determine from the scene context and the convergence angle of the eyes required to merge the left and right images. It thus nearly always does not matter if a block of one saturated colour is next to another block of saturated colour, because the retina detected light intensity will nearly always be different in each block. Where two colours has the same retina detected intensity, focussing will be a little harder, especially if teh scen context does not give any clue as to range, but as we can't see in colour sharply it doesn't matter. And where it happens, there will almost always be somewhere else nearby in the image that will provide the intensity (luminence) change.

The difference between a saturated colour and a non saturated colour is that the non-saturated colour has a percentage of ALL other colour wavelengths added to it. White, which is all wavelengths at equal strength, is a total desaturation. This all means that it is desaturated colour objects that are hard to see clearly, not saturated colours - the opposite of what Steve said. As of course any engineer that has designed display systems knows: they go for saturated colours (eg the almost monochromatic red or red light emitting diodes) or just black and white, because both are the clearest to see, not desaturated colours.

However, for those who wear spectacles, colour aberation can be a problem, particularly if they work with computer graphics and CAD. Especially for high refractive index glass (often chosen for cosmetic reasons as it makes for thin lenses for near-sighted people), chromatic aberation of the spectacle lenses can exceed what the eye-brain system can handle. For natural scenes and not too bad a degree of prescribed correction, the brain usually soon learns the new image displacement and re-compensates.

121.215.38.161 (talk) 02:53, 15 September 2013 (UTC)

If you poured Coca Cola onto a frog, does it cause distress and death?

I am not planning to do this, just for the record. But I remember that some kid I went to high school with poured Coca Cola on a frog and it went crazy for a few moments then died. What happened here? Does Coca Cola 'burn' a frogs skin? Does the fizz from the drink cause distress? --Mathmmaats (talk) 10:44, 14 September 2013 (UTC)

Our frog article points out that frogs have glandular skin with all sorts of specialized secretions that are vital to the frog - it's not at all unreasonable that the acidity of the coke would do something bad here. Frog skin is also semi-permeable - meaning that things can pass through it MUCH more easily than (for example) human skin. So your instincts on this (that coke is kinda harmless when poured onto human skin) are totally misleading when it comes to frog skin. I don't know for sure that this is enough to result in distress or possibly death to the frog - but it's certainly not entirely impossible. I'd also note that not all frogs are equal. Some have adaptations to help them live in very dry environments, others have waxy rather than slimey secretions - and their skin is very different from frogs that do not have that adaptation. Our article also says that many frogs are able to absorb water and oxygen directly through the skin - and perhaps absorbing a weak acid - or something laced with CO2 instead of oxygen - would be fatal to them. SteveBaker (talk) 13:44, 14 September 2013 (UTC)

Performing the "experiment" by yourself seems to be useless and cruel. OsmanRF34 (talk) 16:41, 14 September 2013 (UTC)

As stated above I will not be performing this experiment. --Mathmmaats (talk) 17:54, 14 September 2013 (UTC)

Yeah, Osman, have a little read of OP's very first line. What is wrong with posters who can't even take the trouble to read a short and simple post before slamming "Send" on their keyboards? Myles325a (talk) 03:26, 16 September 2013 (UTC)

antidotes for sodium fluoroacetate

Sodium fluoroacetate says "Effective antidotes are unknown". However, as far as I know in China we use acetamide to treat fluoroacetate poisonings and it is said to be "very effective". Can anyone tell me whether there are effective antidotes for sodium fluoroacetate?--Jsjsjs1111 (talk) 11:59, 14 September 2013 (UTC)

I suspect (without evidence) that the term "antidote" is intended for substances that directly counteract the poison. It's possible that the acetamide is only used to treat some of the symptoms of poisoning. This is an odd claim though - neither our article on acetamide, nor any of the usual chemical databases that I could readily access, list any effects on the human body - either positive or negative. This lack of information on the substance as a drug makes it an unusual choice. SteveBaker (talk) 12:32, 14 September 2013 (UTC)

Are you perhape thinking of sodium fluoroacetamide instead of Sodium fluoroacetate? While our article doesn't mention it, I think sodium fluoroacetamide poisoning can be somewhat counteracted by acetamide [13], [14] (refers to rats), [15] (note that the later source is a Chinese chemical seller). Before I read the last source, my hypothesis was that fluoroacetamide is most likely metabolised to fluoroacetate to some extent hence fluoroacetamide toxicity arises from the same mechanism as fluoroacetate toxicity and could be partially counteracted by giving acetamide to compete and drasticly limit the metabolism of fluroacetamide to fluoroacetate, similar to the way ethanol is given for methanol poisoning. The Chinese source while far from an RS suggests something similar except that it suggests fluoroacetamide is metabolised to fluoroacetic acid. It seems to me it would make more sense to give acetate for for fluoroacetate poisoning yet I suspect that won't work considering the significance of acetate (i.e. giving an overdose of acetate will probably kill anyway) and the fact you're too far down the metabolic chain considering the apparent inhibition strength (meaning you have to drasticly reduce fluoroacetate metabolism not just limit it a bit). Nil Einne (talk) 16:53, 14 September 2013 (UTC)

The original poster is correct in principle, though I'm not sure if something like acetamide is truly an antidote. (The goal is to slow the poison rather than neutralizing it; nonetheless, it is something "given against" poison) [16] The idea is that sodium fluoroacetate gets drawn into the citric acid cycle and jams it (read the article for details). So far as I know fluoroacetamide should work the same way - the tail end is removed from either in favor of the CoA. The purpose of acetamide and other treatments such as ethanol is simply to provide the citric acid cycle with more input material, which would compete with the poison for preference. (I suppose that just having eaten a fatty meal before the exposure would be helpful in the same way - haven't verified that) I have not chased down the details of the substrate specificity of pyruvate dehydrogenase to see whether certain compounds would have preference, but I assume the use of acetamide on actual humans implies it was the best examined at the time. Wnt (talk) 20:14, 14 September 2013 (UTC)

Thank you! I guess Wnt's right. But regarding the definition of "antidote", it is stated in the antidote article that ethanol is the antidote of methanol.--Jsjsjs1111 (talk) 11:44, 15 September 2013 (UTC)

Good point! On further consideration, I suppose this is the only workable way to decide the semantics, on the basis of what the medical practice is, rather than any more rarefied notion in theory. Wnt (talk) 14:25, 15 September 2013 (UTC)

Marine Fossil

Does anyone know what this fossil is? I am guessing some sort of scallop or mussel - it was found at Kettleness near Whitby.--Gilderien Chat|List of good deeds 18:54, 14 September 2013 (UTC)

Hmm, it looks like one of the two shells from some type of bivalve, with the hinge visible at the bottom. It's oddly non-symmetrical, but that could be due to distortions caused in the rock over millions of years. In particular, it looks like the lower, left side has been stretched out. StuRat (talk) 03:00, 15 September 2013 (UTC)

Indexing my technology company on Wikipedia

How can I have Wikipedia Index my technology company, including our products, history, website, etc.?

Thanks

J.Pamelia, CEO EZCO MEDICAL SYSTEMS EZ COURSES.ORG http://www.ezcourses.org— Preceding unsigned comment added by EZCO MEDICAL SYSTEMS (talk • contribs) 21:01, 14 September 2013 (UTC)

Become notable enough earn it. Also see what Wikipedia is not, in particular that it's not a directory. WegianWarrior (talk) 21:16, 14 September 2013 (UTC)

This isn't really the right place to ask, but the key thing to note is WP:GNG, which lays out the basics. Have good third party sources reviewed the company's activities? Newspapers, magazines, reviews of the industry, that kind of stuff. Wikipedia covers things after other sources have written about them. Also be warned that there is a great confusion and controversy about WP:COI - people make perhaps unrealistic policies, while others badly abuse the system. Done improperly, you could end up getting a bad image out of this so be careful. The gold standard is that you set up a page User:(Your handle)/My draft article and get a third party to review it and move it into mainspace. I say (Your handle) rather than EZCO MEDICAL SYSTEMS because I fear you're about to be told that this isn't a proper username (Wikipedia takes all kinds of aliases, but it wants accounts to be used by one person who is responsible for everything, not a group of people who can pass the buck at each other, nor does it want trademark lawsuits over who holds the name) Wnt (talk) 22:24, 14 September 2013 (UTC)

To state that simply, get mentioned for notable accomplishments in books or periodicals outside trade magazines and advertisements. If, for example, you build a better mousetrap, and Time Magazine does an article on you, you are set. μηδείς (talk) 00:16, 15 September 2013 (UTC)

"In nature, on average, only one baby makes it to adulthood, per parent."

I'm having trouble understanding this statement, made by Thomas R. Holtz, Jr.. Wouldn't that mean that the Earth's biomass is not increasing at all? Wouldn't that mean that a very large number of species are going extinct simply by having a less than average number of surviving offspring? Surtsicna (talk) 22:19, 14 September 2013 (UTC)

The premise appears to be that the carbon cycle is working with a fixed amount of material (largely though not entirely true in the long run), and that the average size of organisms is not decreasing, and that the amount of biomass in organisms that don't count as "babies" or "adults" (bacteria?) remains a constant proportion. Wnt (talk) 22:27, 14 September 2013 (UTC)

Sure, the biomass of a given species will wax and wane, and some will go extinct. Mathematically speaking, if there were considerably more that one offspring reaching reproductive age on average for each member of every species, then biomass would exhibit positive exponential growth, and accelerate quickly to unreasonable sizes (e.g. the carbon and raw material limits mentioned by Wnt). However, if that number is less than one on average, then everything is (perhaps slowly) headed to extinction, and all the biomass eventually goes away. So saying that each individual gives off one offspring on average is a fair statement, if you take the long enough view and ignore a lot of details (also careful on the phrasing, we don't want to condition on the assumption that an individual is a parent). Surely human populations have been skyrocketing, as with our commensal species. But this is at the expense of a lot of other biomass, and it remains unclear how long out species and society will last on evolutionary, let alone geological time scales. All this reasoning does imply (or assume, depending on how you look at it) a global biomass that doesn't change too much when averaged over relatively long time scales, i.e. barring dramatic shifts in climate, etc. See also logistic growth and carrying capacity for related information. SemanticMantis (talk) 23:42, 14 September 2013 (UTC)

On the long term, it doesn't make sense. Unless you believe that all the number of individuals is stable, for every species. Either he meant "at least one individual" or I don't know what he means. Can you provide the source of this assertion: "In nature, on average, only one baby makes it to adulthood, per parent." ? Google point to this page. Maybe the quote is not authentic.OsmanRF34 (talk) 23:52, 14 September 2013 (UTC)

diversity in number of existing genera

There's no need to or point in going into abstruse side issues. If a population is not growing or shrinking, then on average two parents have two children that survive to reproduce, or one child to replace each dying individual. μηδείς (talk) 23:58, 14 September 2013 (UTC)

That's mathematics and simple logic. What's the point of saying this at all? OsmanRF34 (talk) 00:00, 15 September 2013 (UTC)

Oddly, a lot of people find this extremely hard to grasp, as I know from taking an upperlevel class on ecological modelling. Extra credit. What's the only thing you know every single one of your ancestors accomplished? μηδείς (talk) 00:08, 15 September 2013 (UTC)

Then, there should be a Holtz's principle in biology. OsmanRF34 (talk) 00:09, 15 September 2013 (UTC)

I think Medeis is hinting that this hypothesis is not nearly as profound as it might seem at first. And you have to include various conditions to make it work. Consider the bacteriophage, a virus (i.e. an organism of sorts) that can have as many as 900,000,000 individuals in a mere thimbleful of sea water. And a lot of the extinctions in recorded history have been due not to "natural" environmental pressure, but rather due to human behavior ranging from indifference to deliberate slaughter of a species. It occurs to me that the author of that statement should give credit to the one he probably got the idea from, Blood, Sweat & Tears ←Baseball Bugs ^{What's up, Doc?} carrots→

This is standard population ecology and population dynamics. Population 1 equals population 0 plus births minus deaths plus immigrants minus emigrants. If change is zero and migration is zero then births equal deaths. This is easiest to see in populations with discrete annual generations, but it applies in all cases, as well as humans. The math was worked out by the 1930's, so no credit to Holtz. See also population genetics. μηδείς (talk) 00:28, 15 September 2013 (UTC)

Note: in the above I was taking this as a statement about the average of all species. Where individual species are concerned, clearly some will go extinct and others have long-term success, becoming families, orders, and in the fullness of time, perhaps one day even supplanting most other organisms in existence. But even if these factors apply, the effect is small: for example, suppose that there are two organisms now, and one day 560 billion tonnes of biomass will be almost all composed of 1-kg organisms of this type. Well, that 250,000,000,000,000-fold increase in numbers is roughly 2⁴⁸, so if this evolutionary revolution takes only 48,000 years, that still means a doubling of numbers every 1000 years. If these organisms have an average of 100 years generation time, that means the number of offspring averages around the tenth root of 2, or 1.07 per parent. But if it takes more than 48,000 years to drive all other species extinct, if the lifespan is shorter than 100 years, if the organisms are larger, etc. it all makes that number even closer to 1.00 Wnt (talk) 04:06, 15 September 2013 (UTC)

It is a reasonable assumption that if the total biomass of the earth has increased over time, the number of individual animals and non-clonal organisms may have increased. The number of genera has been increasing due to the increasing variety of flowering plants, which is much greater than that of the non-flowering plants during the age of reptiles. The number of insect species has increased over that time, with each plant being said to have its own species of beetle, and each beetle its own species of parasitic wasp, and so on. It seems reasonable to assume this means a steady increase in the number of individuals over time. Obviously the colonization of the land would have had that result. μηδείς (talk) 17:40, 15 September 2013 (UTC)

Flagellum-driven vehicles

Throughout microbiology a flagellum appears to be the greatest thing ever. Swimming animals don't use them, but this might be due to the limitation that they aren't set up to easily have a body part rotate around and around. So... how well does a flagellum work if well engineered for use with a sub, ship, plane, airship, etc.? Are there examples where people have tried their best with it, and how does it measure up? Wnt (talk) 22:32, 14 September 2013 (UTC)

It's a question of scale and the relative viscosity of water at different scales. See Reynold's number. Someone versed in physics can probably give a better answer. μηδείς (talk) 00:02, 15 September 2013 (UTC)

Agreed. While it could work at a macro scale while moving through a rather thick liquid, we tend not to encounter those much. However, at a smaller scale, even water behaves like a thicker fluid. The way in which water bugs can stand on the water shows this effect. So, to move microscopic nanobots through water (or blood, etc.), flagella may work well. StuRat (talk) 02:53, 15 September 2013 (UTC)

I understand about the viscosity, but I'm not so clear on how quickly the alleged inefficiency sets in with increasing scale or decreasing viscosity. Even if a flagellum-driven vehicle were a toy operated in honey, seeing it in operation, and how engineers would try to optimize it, would still be a really interesting learning experience. Surely someone must have tried? Wnt (talk) 03:18, 15 September 2013 (UTC)

I think the difficulty in replicating a flagellum mechanically is a problem, too. We might well make some form of one, but getting the whip action just right would be difficult. It's analogous to, in flight, using flapping wings versus fixed wings. While people have played around with ornithopters at least since Da Vinci, none of them have ever been a practical form of human transportation.

I believe scientists are working on an artificial jellyfish, though. There the bell contracts together, rather than multiple flagella which must work together, somewhat simplifying things. The idea would be to use it to sneak a camera or other payload close to an enemy, who would think it was a normal jelly. StuRat (talk) 07:27, 15 September 2013 (UTC)

Sorry, I didn't mean to restrict consideration to things that can transport humans. With ornithopters there are lots of examples. And the engineering challenge is what would make it interesting to see what people come up with! Wnt (talk) 14:59, 15 September 2013 (UTC)

Googling "flagellum-driven robot" resulted in this relevant link, as well as this link in which reference 144 seems to address the question. As others have stated, it appears to be feasible only on the microscopic scale. --NorwegianBlue ^talk 17:13, 15 September 2013 (UTC)

These were interesting links. The former source suggests there is still more uncertainty than I would have imagined about whether the scale of a flagella-driven vehicle has any effect on its efficiency - the main issue being whether the Reynolds number of the fluid at a given scale permits the use of other methods of inertial propulsion such as fins. They still seem to fall well short of being optimally engineered for their size, however, even so far as helical properties. Wnt (talk) 14:47, 17 September 2013 (UTC)

It might work for macroscopic object as well, because you are free to use a large number of microscopic flagella. Count Iblis (talk) 16:03, 17 September 2013 (UTC)

heart acceleration

What causes the human heart to accelerate? Or put another way: what are the actions or materials that cause a human heart to beat faster? --66.190.69.246 (talk) 23:59, 14 September 2013 (UTC)

The release of adrenalin and the stimulus of the sympathetic nervous system. μηδείς (talk) 00:11, 15 September 2013 (UTC)

And, of course, this is done because the body detects a need for a faster heart at that time. This can be, for example, if performing difficult physical activity, where the muscles need more oxygen than usual. Moving the blood more quickly helps to meet this increased need. The anticipation of the need for physical activity can have the same result, say when facing a fight. Unfortunately, this last mechanism seems rather defective in humans, such that just being worried about some possible future threat causes your heart to race now. Other animals tend to only worry about the immediate future, and thus it's not a problem for them. And humans apparently haven't been worrying about the distant future long enough for our bodies to have evolved the ability to distinguish between an imminent threat, where a rapid heartbeat is required, and an eventual threat, where it is not. StuRat (talk) 02:48, 15 September 2013 (UTC)

September 15

Tungsten carbide is inorganic?

It says at Tungsten carbide is inorganic, but I thought the definition of organic simply means that it has carbon in it. ScienceApe (talk) 00:11, 15 September 2013 (UTC)

Organic compound, first paragraph has the answer. OsmanRF34 (talk) 00:16, 15 September 2013 (UTC)

Yes, well, then it should be fixed as hydrogen carbide may just as well be the mascot for organic compounds. Plasmic Physics (talk) 10:46, 15 September 2013 (UTC)

Is there anyone in this century that still calls methane 'hydrogen carbide'? TenOfAllTrades(talk) 04:03, 16 September 2013 (UTC)

It's an extreme example to prove a point: how arbitrary, inconsistent, and useless, the designation of '(in)organic' is. Plasmic Physics (talk) 00:59, 17 September 2013 (UTC)

Plank length

Moved from Wikipedia:Reference_desk/Humanities. OsmanRF34 (talk) 02:57, 15 September 2013 (UTC)

If one had an oak plank board that was 2 by 12 and weighted 100 pounds how long would it be (estimate)?--Christie the puppy lover (talk) 22:50, 14 September 2013 (UTC)

See Specific Gravity Weights Of Materials from READE.

—Wavelength (talk) 23:48, 14 September 2013 (UTC)

See Planck length. μηδείς (talk) 00:43, 15 September 2013 (UTC)

Haah! Clarityfiend (talk) 02:46, 15 September 2013 (UTC)

I was going to say that myself. :-) StuRat (talk) 03:11, 15 September 2013 (UTC)

You mistyped the question. Plank length has worked fine for 8 years. PrimeHunter (talk) 12:08, 15 September 2013 (UTC)

Note that a board sold as "2 x 12" isn't necessarily really 2 x 12. According to Lumber#Dimensional lumber, it's really 1.5 x 11.25 inches. This will significantly affect your calculations. StuRat (talk) 03:11, 15 September 2013 (UTC)

Now that simplifies it. I'll take it from here. Thanks for the very nice answers.--Christie the puppy lover (talk) 11:48, 15 September 2013 (UTC)

You're quite welcome. StuRat (talk) 12:35, 16 September 2013 (UTC)

Heh. Depends if it's a physics question or an engineering question. --jpgordon^{::==( o )} 20:21, 15 September 2013 (UTC)

I tend to think most questions involving wood planks are engineering/carpentry questions. StuRat (talk) 12:35, 16 September 2013 (UTC)

Resolved

StuRat (talk) 12:35, 16 September 2013 (UTC)

My nuts are overly saturated

Is it possible to breed or genetically engineer the saturated fats out of tree nuts and peanuts, or is there some reason why this wouldn't work ? The reason I ask is that these would seem to be an ideal source of protein, especially for vegetarians, if not for the sat fat. I would anticipate that nuts with only unsaturated fats might tend to seem greasier, since the fats would be more liquid, but that would be OK by me. StuRat (talk) 04:02, 15 September 2013 (UTC)

The purpose of the fat is to nourish the embryonic plant. If you mutate the plant, then grow it from a cutting, rather than a seed, you can breed out traits otherwise necessary for the seed's survival. Indeed, that is how they breed seedless plants, from mutated cuttings. μηδείς (talk) 04:06, 15 September 2013 (UTC)

Note that I don't want to remove all fats, just the saturated fats. StuRat (talk) 04:16, 15 September 2013 (UTC)

See selective breeding and seedless fruit and apply the notion of getting rid of the saturated fat instead of the seed as a whole. μηδείς (talk) 19:36, 15 September 2013 (UTC)

The notion of a seedless peanut is interesting. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:44, 15 September 2013 (UTC)

I'm still waiting for the boneless chicken. And as a plus, they should be a lot easier to catch. :-) StuRat (talk) 07:38, 15 September 2013 (UTC)

It's not all that obvious the saturated fat is bad - it's not "physics". Eating the nuts seems to be beneficial overall. See [17] for example. I would put the empirical evidence that nuts are good far above the theory about any improvement that might be made. The composition of dietary fat, its uses in the body, its basis as the biochemical origin of a vast network of eicosanoids, prostaglandins and cannabinoids ... we may not know what alterations of the plants would be good for us, and it is hard to collect sufficient data. Wnt (talk) 04:13, 15 September 2013 (UTC)

Fittingly, given the title of this section, it appears that the way Rocky Mountain oysters are typically prepared, they would be right much fatty. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:04, 15 September 2013 (UTC)

Solar eclipses

These question grow out of my memory of seeing an eclipse in the 2000s, either the Solar eclipse of December 14, 2001 or the Solar eclipse of April 8, 2005: we were on the edge of the partial eclipse, and the only ways I knew that an eclipse was happening were (1) reading about it, and (2) seeing a tiny chunk missing from the bottom of the Sun when viewing it with welder's glass.

1. In general, what percent of the Sun must be covered for the eclipse to cause a noticeable darkening of the sky, assuming a cloudless day? In other words, imagine that you're sitting on the ground, looking around at everything in front of you (but not to the point that you're obsessed and ignoring everything else); in this situation, when will you start noticing if your eyes are normal and you're not paying particular attention to the Sun?
2. When a total eclipse occurs and you're out of the path of totality but not out of the path of partiality, part of the Sun will be obscured. Is there a relationship between (1) the portion of the Sun that's obscured, and (2) the direction from you to the location where the eclipse is total? During the eclipse in question, I was far to the north, and the "missing" chunk was at the bottom of the solar disk. If I'd been way to the south, would the chunk be missing from the top? Or would it have been missing from one side if I'd been at the same latitude but way far east or west?

Nyttend (talk) 04:35, 15 September 2013 (UTC)

1) It will vary from person to person, but note that our eyes' reactions to light levels isn't linear. That is, half as many photons barely makes a difference in the apparent light level, rather than seeming "half as bright". So, based on that, quite a large portion of the Sun might need to be obscured before the light level would change noticeably. Also note that passing clouds can have the same effect, so even if you did notice the change in light level, you might well ignore it. StuRat (talk) 07:19, 15 September 2013 (UTC)

When a large portion of the sun is eclipsed, you might notice something strange about shadows -- they seem to have less sharp edges. I noticed this in the 2001 eclipse. Dbfirs 08:14, 15 September 2013 (UTC)

I've experienced only partial solar eclipses, so I can't give you a quantitative answer. But I recall an eclipse that covered well over half the sun in my area, and the effect was not the same as simply an overcast sky. The way I like to describe is it's as though the sun were on a dimmer switch. But even at more than half the sun covered, there was no problem seeing; it was still sufficiently bright. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:47, 15 September 2013 (UTC)

Actually, a 50% eclipsed sun is still 50 times brighter than an overcast day. SteveBaker (talk) 14:58, 15 September 2013 (UTC)

Full sunlight is a thousand times brighter than a well-lit room and it's 100 times brighter on a "sunny" day than on an overcast day. Since our eyes and brain compensate for this massive difference, we don't especially notice the brightness difference between the two unless we step from one to the other very quickly, it would be hard to tell the difference between the normal sun and (say) a 75% covered sun without looking directly at it (through welders' glass or whatever).

If you didn't happen to look at the sun, you'd never notice a 75% partial eclipse because it's still brighter than an overcast day...not much different than when a cloud passes in front of the sun.

However, in a full eclipse, the sun almost completely vanishes behind the moon (and there is no moonlight of course) - so everything looks as dark as night....often quite a bit darker because street and building lights - and most of the other sources of light pollution such as car headlights are not turned on because everyone is standing around excitedly watching the once-in-a-lifetime total eclipse. The sky is black and you can see the brighter stars. But that period of "totality" is generally quite short and as soon as the sun starts to be uncovered even a little bit, the sky turns blue again and our perception is that it's more like a cloudy day. SteveBaker (talk) 19:41, 15 September 2013 (UTC)

I observed the Solar eclipse of May 30, 1984 as an annular eclipse. As I recall, 85% of the sun was covered. Passersby kept asking me what I was doing -- they had no idea an eclipse was in progress. The only way you could tell by looking around was if you noticed that there was no glare off the chrome of parked cars. Duoduoduo (talk) 18:39, 15 September 2013 (UTC)

Is carbon tetrachloride an organic compound?

The carbon tetrachloride says it is, however "CCl₄" is in Template:Carbon compounds. Which is correct?--Jsjsjs1111 (talk) 11:20, 15 September 2013 (UTC)

To clarify, Template:Carbon compounds is specifically/only inorganic ones--naming threw me a bit. Our organic compound has some cited commentary on the uncertainty of the limits of that category, so I'm not sure there is a good answer. But we should at least be self-consistent and hopefully have WP:CITE to support whichever way we go. DMacks (talk) 11:36, 15 September 2013 (UTC)

Yes this template is confusing. Apparently it is missing cyanogen, tetrabromomethane, etc.--Jsjsjs1111 (talk) 11:47, 15 September 2013 (UTC)

Also, that template is redundant to Template:Inorganic compounds of carbon (need to merge them and kill one, once someone figures out what operational definition to use). And missing several other carbon–oxygen ones. There seem to be articles about almost thirty (!) such, but some are closer to some definitions of "organic" than others. DMacks (talk) 12:47, 15 September 2013 (UTC)

Jsjsjs1111 and DMacks, please note that I've sent the templates to TFD. Nyttend (talk) 20:11, 15 September 2013 (UTC)

Quality of light needed to charge from solar panel

I was wondering if natural light is needed to charge devices that use solar panels. I've tried to charge a solar phone charger using indoor light from florescent bulbs, but it didn't seem to charge. Direct, unclouded sunlight was needed to charge it at all. Are there different types? I can find nothing about it in the Solar panel or solar cell articles.--Auric talk 13:16, 15 September 2013 (UTC)

While there is some relevant solar cell physics here, your problem is a universal feature that you would always encounter with any device that converts light into energy. If you reduce the intensity of the power source, you obviously won't be able to draw as much power from the device. This means that for the same current the voltage must be lower (if you can draw that current at all). Now for your battery charger, the voltage is critical, if this drops below a certain value (which changes during the charging process), it won't work.

Note that natural light is hugely more intense than indoor light, we don't notice this because the brain automatically compensates for this. Count Iblis (talk) 13:42, 15 September 2013 (UTC)

Yes, indeed! To put numbers on that, our Sunlight article says that at ground level, the noonday sun can deliver 1004 watts per square meter, which is composed of 527 watts of infrared radiation, 445 watts of visible light, and 32 watts of ultraviolet radiation. Standard solar panels only use visible light to generate power - so we should go with the 445 watt number. Compare that to a 100 watt light bulb - which (being only about 3% efficient) produces something like 3 watts total - spread over the entire room! So you'd need around 150 hundred watt bulbs, with reflectors behind them to direct all of the light onto a one square meter solar panel! Since even the best solar panels produce 160 watts per square meter - this would require 100 times as much electricity to light the bulbs as the system would produce! Even using LED lamps (which are the most efficient way to generate visible light that we can buy) - you'd need ten times as much electricity as you'd make from the solar panel.

From the point of view of recharging your phone from ordinary room lighting, the engineering standard for "normal" room lighting is 150 lux. Full sunlight is 100,000 lux. So expect your phone to charge about 650 times slower than it would in direct sunlight! The standard for office and workshop lighting is 500 lux - but you're still going to have to wait 200 times longer! Even on an overcast day, the sun delivers 1000 lux. SteveBaker (talk) 14:43, 15 September 2013 (UTC)

A good example is when driving on a sunny day. The driver and passengers in other cars are pretty much shrouded in seemingly very dim light until you get very close to the car. Vision is an amazing system. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:51, 15 September 2013 (UTC)

Eigenstate Symmetry

It is often said that the ground state of a system must respect the symmetries of the Hamiltonian. Is this strictly true? Even if there are multiple degenerate ground states? — Preceding unsigned comment added by 31.55.103.72 (talk) 17:00, 15 September 2013 (UTC)

Not if the ground state is degenerate, but in that case you can choose them to respect the symmetries of the Hamiltonian. Count Iblis (talk) 17:21, 15 September 2013 (UTC)

No, if the ground state is degenerate it may be impossible to find a ground state solution that respects all the symmetries of the Hamiltonian. That's how the Higgs mechanism works and leads to spontaneous symmetry breaking. Nothing surprising there. Try placing a sphere on a table and placing a second sphere on top of the first. The Hamiltonian has axial symmetry. But the ground state is achieved when the top sphere rolls to one side. This ground state is degenerate(since there are many directions for the ball to roll to) and does not have axial symmetry. Dauto (talk) 17:37, 16 September 2013 (UTC)

On the other hand, you could presumably find a linear superposition of such states which did have the axial symmetry. So why is this not physical? Jheald (talk) 18:25, 16 September 2013 (UTC)

Such a superposition would have nonlocal properties. So, if you imagine that there are observers then they will end up observing the system in a localized state. But then a Many Worlder will argue that you still have a symmetric state but this involves the observers being entangled with the system, this is then a superposition of all the possible ways the symmetry can be broken. Count Iblis (talk) 18:43, 16 September 2013 (UTC)

Food energy

How is it calculated actually? It's clear that alcohol has, thermodynamically, lots of calories, and so is the case of straw and grass. But shouldn't food calories only be things that we can absorb as calories? So, if they tell you alcohol has say 1000 kc for 1 l, does it mean that you can use those calories as a form of energy? OsmanRF34 (talk) 18:04, 15 September 2013 (UTC)

Celery, made up of lots of long sugars, presumably has lots of calories, even though none of the sugars are digestable by the human body. A package of celery with Percent Daily Values (image is here, in case you're not familiar with the name) will tell you that it has no calories, so it's clear that in this context, it's only things that we can absorb as calories. Nyttend (talk) 20:16, 15 September 2013 (UTC)

As that article itself says:

direct calorimetry would give systematic overestimates of the amount of fuel that actually enters the blood through digestion. What are used instead are standardized chemical tests or an analysis of the recipe using reference tables for common ingredients[8] to estimate the product's digestible constituents (protein, carbohydrate, fat, etc.). These results are then converted into an equivalent energy value based on the following standardized table of energy densities.

DMacks (talk) 04:14, 16 September 2013 (UTC)

As I understand it, first they dehydrate the item to be tested, then they add fuel and burn it. The amount of heat produced in excess of that produced by the fuel alone is the raw number of calories. However, it then gets tricky when dealing with indigestible calories. This requires them to determine the percentage of the total calories which are digestible, which is done via a number of theoretical and experimental methods. Another wrinkle is that it also takes calories to digest food, so this should really be subtracted to calculate the net calories gained from each food, but this is further complicated by the fact that each person's digestive system has a slightly different efficiency in digestion, and certain combos of foods might be easier to digest than others. So, they don't even attempt to account for this. StuRat (talk) 04:21, 16 September 2013 (UTC)

Yes, it's a hard question. To give a concrete (if extreme) example, if you were to eat a raw potato (which I strongly do not recommend you try!!) - and swallowed it in large chunks without much chewing - then the starch that's inside the cells of the potato wouldn't be metabolized into sugars and then absorbed into the blood stream because the cell walls of the potato are made of cellulose - and humans lack the ability to digest that. The undigested potato passes right through your gut, almost unchanged. When you cook a potato, you rupture the cell walls, releasing the starch so you can digest it. The theoretical calorific value of a raw potato (calculated by the drying and burning method) is exactly the same as for a cooked potato - but the number of calories you'd absorb from eating it raw would be almost zero - compared to around 100 to 200 calories if you cooked it. SteveBaker (talk) 16:38, 17 September 2013 (UTC)

Two Astronomy Questions

So I'm writing a science fiction story, and I'm having a lot of trouble determining where things are.

First, is there some way of telling how far a planet or moon will be from another planet or moon at a particular date? All I've been able to find is approximate distances from Earth or the sun, never exact distances. I mean it's the easiest thing in the world to find that Mars will be in Pisces, and Jupiter in Aquarius, but that tells me virtually nothing about the distance between the two.

Secondly, what directions should I be using? From google searches, I've found the directions North & South (toward & away from Andromeda), Coreward & Rimward (toward and away from the core, which is in Sagittarius from our perspective), and Spinward & Trailing (which I can't identify). Various science fiction roleplaying references give me various stars which are supposedly Spinward or Trailing, but all of these stars seem to be in the wrong places when I compare them to actual constellation maps or galactic maps. So what's the story with these directions, and are these even the directions I should be using for travel inside the solar system?

67.142.167.20 (talk) 18:44, 15 September 2013 (UTC)

Are you looking for the real locations of actual objects in our solar system at specific future dates? Or are you writing about fictional moons and planets, and trying to describe them realistically? It sounds like you're interested in travel within the solar system, so you'd want to use heliocentric ecliptic coordinates. This is a set of spherical coordinates centered on the Sun. It's similar to latitude and longitude on the Earth's surface, with a third coordinate: the distance of a location from the center of the Sun. The planets orbit in the "equator" (the ecliptic), and the poles point out of the plane of the solar system. If you want the locations of real solar-system objects at future dates, you'll want to use one of the ephemeris services you can find online. If you give a bit more info about what you're looking for, I'm sure someone here can help you get started. --Amble (talk) 22:23, 15 September 2013 (UTC)

On second thought, instead of using an ephemeris server you should probably check out Celestia. It's a free-software program that lets you see the sky from wherever you like at a future date. For example, you could ask for the view from a particular place on the surface of Ganymede on this date in 4010. --Amble (talk) 22:30, 15 September 2013 (UTC)

(ec)There is the galactic coordinate system for positions of stars in the galaxy. However, this is not a suitable system for travel within the solar system. Yes, we can compute the distance between any two solar system planets to a reasonable degree of precision (given the size and irregularities of the bodies, it makes no sense to compute the distance to meters). For coordinates in the solar system, the ecliptic coordinate system is probably easiest. --Stephan Schulz (talk) 22:35, 15 September 2013 (UTC)

You didn't tell us about your math background, so I'll just describe how I would do it and you can ask for clarification if you don't follow. Go to NASA's HORIZONS service, choose a target body (say Mars), and choose a date range. Afterwards, click "change" next to Table Settings and select Heliocentric ecliptic lon. & lat. and Heliocentric range & range-rate. This gives you the Mars' position in a spherical coordinate system centered on the Sun, so it tells you exactly where Mars will be. Finally, click Generate Ephemeris. To calculate the distance to another planet, get the coordinates for that other planet and calculate the distance between the two sets of coordinates. --Bowlhover (talk) 00:44, 16 September 2013 (UTC)

Hydrochloric acid changed the colour of plastic tube

I had some concentrated hydrochloric acid in a 50 ml tube (polypropylene) for a few months, stored in mostly darkness. The tube seems to have changed in colour to a sort of light pink (still translucent). Why has the tube changed colour? — Preceding unsigned comment added by 78.150.23.174 (talk) 18:47, 15 September 2013 (UTC)

I don't know, but it might help if you specified the temperature at which it was stored and the pre-storage colour of the tube. Nyttend (talk) 20:14, 15 September 2013 (UTC)

The tube was clear (transparent) and the storage temperature was 18-24 C. — Preceding unsigned comment added by 78.150.23.174 (talk) 20:59, 15 September 2013 (UTC)

Well, that's pretty weird -- polypropylene is a long-chain aliphatic compound, and thus is supposed to be inert to acid-catalyzed reactions. The only thing I can think off the top of my head is free-radical chlorination, but that requires UV rays (such as from sunlight) as well as free chlorine in the solution -- so, since you kept the test tube in darkness, that can't be it either. Anyone else have an idea what's going on? 24.23.196.85 (talk) 01:03, 16 September 2013 (UTC)

My first thought is to find out what the plasticizer is. Wnt (talk) 02:25, 16 September 2013 (UTC)

Oh yeah, if there are phthalate/terephthalate esters (or any other kind of esters, for that matter) in the plastic, you get hydrolysis and possibly alfa-substitution and/or aromatic chlorination reactions as well. So yes, this could be responsible for the discoloration. 24.23.196.85 (talk) 03:16, 16 September 2013 (UTC)

Leaf fluffies

Resolved

File:Leaf Fluffies.jpg

Leaf fluffies

Does anyone know what these fluffy things are on the leaf (two views provided at right)? DRosenbach ^{(Talk | Contribs)} 20:43, 15 September 2013 (UTC)

They look like galls. This page has an idenfification tool that might help narrow it down a bit. - Karenjc 22:15, 15 September 2013 (UTC)

I was thinking of something like that too, but the photos are not clear enough. Can you possibly get a good close up? The type of plant the leaf is from may help too. (oak?) 'Fluffy' suggested caterpillars, but they aren't are they? This page Oak Gall Gazetteer may help, "the shaggy-looking HAIRY OAK GALLS produced on the upper leaf surface by A. villosa;". (Hairy Gauls, miniature Tribbles? ;-) )-ө- 220 of ^Borg 03:30, 16 September 2013 (UTC)

This flickr picture looks very similar Oak Leaf Hairy Gall. ӧ 220 of ^Borg 03:46, 16 September 2013 (UTC)

Yes -- thank you all! DRosenbach ^{(Talk | Contribs)} 23:58, 16 September 2013 (UTC)

Relativistic speed

Is there anything in this universe that travels at relativistic speeds, aside from subatomic particles? Is there anything macroscopic, aside from possible alien technology? For convenience, let's arbitrarily define relativistic to mean v > 0.2c. --140.180.246.129 (talk) 21:08, 15 September 2013 (UTC)

Galaxies located far away (due to the expansion of the universe). Also, closer to home, in case of supernova and hypernova explosions, matter gets ejected at extreme relativistic velocities. Count Iblis (talk) 21:15, 15 September 2013 (UTC)

Here I've got to say I'm only guessing, but I thought that you could NOT include the Red Shift of galaxies, as this comes about from creation / dilution of space between the galaxies from when they were first formed. This kind of recessional velocity could be faster than the speed of light, I had thought. Indeed, if our universe is not confined to that which is "observable", then we must admit that there are galaxies beyond the observable ones, and these must be travelling faster than c, relative to us, (as we do with respect to them). Myles325a (talk) 03:21, 16 September 2013 (UTC)

There are stars orbiting the supermassive black hole in the center of the galaxy (Sagittarius A*) that travel pretty quickly, but the fastest is S2 (star) at 1.67% of the speed of light. That doesn't meet your 0.2c criterion. The stars of the double pulsar PSR J0737-3039 only move at about 0.1% of c. As the Count points out, distant galaxies have recessional speeds that can be very large, but I assume you want something that's traveling with v > 0.2c relative to its surroundings. The polar jets of supermassive black holes and even stellar-mass black holes can be very relativistic, well over your threshold. They are jets of plasma, not just particles, and they're pretty well macroscopic. --Amble (talk) 22:15, 15 September 2013 (UTC)

Velocity is relative! A velocity cannot be ascribed to an object! Velocity is a description of a relationship between two objects!! — Preceding unsigned comment added by 86.189.1.198 (talk) 23:11, 15 September 2013 (UTC)

That's true, but most of the time we assume a velocity is measured "relative to its surroundings", so the question makes good sense if we assume "travels at relativistic speeds" means relative to a reference frame in which the other objects of significant size have velocities very much less than c. Dbfirs 08:21, 16 September 2013 (UTC)

The numbers in the infobox for PSR J1748-2446ad, the fastest known millisecond pulsar give a surface velocity of about .128c assuming the radius is 16km (the upper bound in the infobox). Katie R (talk) 14:40, 16 September 2013 (UTC)

Actually, it looks like I read 16km as the diameter when it is actually the radius - the article itself mentions that the surface velocity is about .24c. It really shows how incredibly dense a neutron star is when you consider that gravity manages to keep it from flying apart even though it is rotating that quickly. Katie R (talk) 15:01, 16 September 2013 (UTC)

Relativistic Jets. Dauto (talk) 15:34, 16 September 2013 (UTC)

Mycoremediation of Sarin for Gas Masks

I've read that most of the information regarding the mycoremediation of Sarin; including the species involved is classified by the United States defense department; however in theory could the mushrooms that bio remediate sarin be used as part of a cheaply distributed gas mask? — Preceding unsigned comment added by CensoredScribe (talk • contribs) 22:07, 15 September 2013 (UTC)

That would depend not on how efficiently they process (detoxify) sarin, but how efficiently they absorb it from the air. And I don't think anything currently available (including mushrooms) can beat activated charcoal in terms of absorption efficiency (well, technically adsorption efficiency in this case, but you got the point, right?) In other words, it's one thing to detoxify sarin in the ground, and another thing entirely to remove it from the air we breathe. 24.23.196.85 (talk) 00:50, 16 September 2013 (UTC)

Mycoremediation relevant link. ж 220 of ^Borg 03:40, 16 September 2013 (UTC)

The problem is all a matter of speed. A human doing moderate exercise needs around 40 liters of air per minute - extracting the toxin from that volume of air in that amount of time will be the issue here. The Mycoremediation studies probably do things like planting a bunch of mushrooms in a container with maybe a liter of contaminated soil, waiting a few weeks and seeing if the amount of toxin was reduced by 10%. We need 40 liters to be reduced by close to 100% within one minute - using only enough mushrooms that could fit in a 10cm cube - and for them to be able to continue to do that for hours. That's asking a hell of a lot! SteveBaker (talk) 14:46, 16 September 2013 (UTC)

Powerful singing voice before infections?

This is really weird...right before I get a bad ear infection or a case of strep, my usual 2.5 octave (my bottom sounds like Rick Astley, so it's not as high as you would think) singing voice with excessive vibrato turns into a well managed 4 octave powerhouse. This is 2-3 days before I get a throat or ear infection. It's even weirder because i'm a guy. Any ideas why?
I am not requesting medical advice as (a.) this is not a condition that requires treatment and (b.) I am asking why, not how or how to fix it. --Sean R. Kurth (talk) 22:56, 15 September 2013 (UTC)

(EDIT: Both my school and church chorus teachers have confirmed this odd occurence) — Preceding unsigned comment added by Sean R. Kurth (talk • contribs) 23:29, 15 September 2013 (UTC)

The voice lowering as a result of a throat infection is a common effect. Not quite sure what causes it, though, perhaps a thicker than normal layer of mucous on the vocal folds ? StuRat (talk) 04:27, 16 September 2013 (UTC)

Treating the vocal cords as vibrating strings, we get:

$f={\frac {v}{2L}}={1 \over 2L}{\sqrt {T \over \mu }}$

where $T$ is the tension, $\mu$ is the linear density (that is, the mass per unit length), and $L$ is the length of the vibrating part of the string.

Which means that the heavier the vocal cord gets, the larger $\mu$ becomes and the lower the frequency it vibrates - and as StuRat points out, swelling and increased mucous both contribute to that. SteveBaker (talk) 14:28, 16 September 2013 (UTC)

September 16

"Sea bamboo"

Hi, does anyone know what the stuff described as "sea bamboo" used for making jewellery (shown e.g. here or here) actually is? On Wikipedia, "sea bamboo" directs to Ecklonia maxima, described as a species of kelp, which doesn't seem a likely source for such a material. Could it possibly be Bamboo coral? 86.146.107.83 (talk) 01:10, 16 September 2013 (UTC)

A Google search tells me that "sea bamboo" is a type of Coral.217.158.236.14 (talk) 09:43, 16 September 2013 (UTC)

I have of course done Google searches. I found various references to something called "sea bamboo coral", but the information is a bit confusing. For example, this says that it is "not actual natural coral" but a "product of [a] marine plant". Also, this says that it is a shallow water coral, about which one would assume a reasonable amount is known if it is harvested in such quantities for jewellery, whereas Bamboo coral is apparently a deep-water coral about which "relatively little is known". Is it a different (related?) thing? Shouldn't it be mentioned at Bamboo coral? Yet again, this calls it "a kind of seawater plant fossil", which also does not sound like a coral (though I am aware that there are also plant cells also embedded in coral). 86.160.214.202 (talk) 11:49, 16 September 2013 (UTC)

Has Titan got oil that is not a fossil fuel?

Recently, I had a discussion with someone who is a climate change “denier” and who asserted that crude oil on Earth was not just a fossil fuel, but most (or some) of it originated via simple chemical reactions. He pointed to the “oil” on Saturn’s moon Titan as proof of this*. As a consequence, there is no need to presume that “peal oil” is unavoidable, as it could well be manufactured. I thought that this was typical pseudo-science, but then looked at the WP article on Titan, and this WP one on the possible Colonisation of Titan https://en.wikipedia.org/wiki/Colonization_of_Titan

According to Cassini data from 2008, Titan has hundreds of times more liquid hydrocarbons than all the known oil and natural gas reserves on Earth. These hydrocarbons rain from the sky and collect in vast deposits that form lakes and dunes.[1] "Titan is just covered in carbon-bearing material—it’s a giant factory of organic chemicals," said Ralph Lorenz, who leads the study of Titan based on radar data from Cassini.

This made me take a step back from my pseudo-science accusations.

1. Is it really the case that Titan has oil?

2. Could you process it just like you do crude on Earth and stick it in a car’s engine?

3. Is it the case that oil can be produced in factories, and that there really is no “peak oil”?

4. If some / most Earthian oil is not fossil-based, how much IS fossil-based?

5. Are greenies hiding the truth about a potential sea of non-fossil oil because they want to see us go all wind and solar?

• Yes, he took me by the shoulder, we went out to the back of his yard, and he pointed upwards: "See that?" he said "That's your Titan, and can you make out that glistening patch over yonder? That's oil, gobdarn it, real Texas crude, YEEEHAH! YEEHAH! YEEHAH!" Myles325a (talk) 03:36, 16 September 2013 (UTC)

Here is a link to the NASA source of the text you quoted. Titan's Surface Organics Surpass Oil Reserves on Earth from 2008. ю 220 of ^Borg 03:55, 16 September 2013 (UTC)

1) "Liquid hydrocarbons" isn't necessarily the same as crude oil.

2) Possibly, but it would cost a billion dollars a gallon to bring it here from Titan.

3) Yes, see synthetic oil. However, it's way too expensive to use as fuel for cars, as is synthetic fuel. Also, both of those typically start from other fossil fuels, anyway.

4) I see no evidence of this process on Earth. The difference is that Earth has free oxygen, which tends to react with any hydrocarbons on the surface, to "burn" them, but slowly, over thousands of years (much faster with the aid of bacteria). This is why we don't have lakes of oil on Earth. Only oil underground, protected from this free oxygen, can survive for long here.

5) No. Even if some form of burnable hydrocarbons were produced from inorganic sources, they still wouldn't be produced at anything near the rate we are using them up.

So, it's not about a lack of any fuel, but a lack of cheap fuel. Sucking the raw ingredients out of the ground is the cheapest way to make fuel, and fuel prices will continue to go up as we have to dig deeper, use offshore platforms, etc., to get at the diminishing fuel supply. At some point, alternative fuels will be cheaper than starting from crude oil, and we will start to switch to them (this process has already started in some places). However, we may never get back to prices as low as we had when petroleum was plentiful. StuRat (talk) 04:35, 16 September 2013 (UTC)

Your friend is out of date. See Abiogenic petroleum origin. This theory stated that some (or most) of our oil reserves were created from non-living matter. It's now been all but discredited. The theory is kept alive by people with an axe to grind.

(Although, interestingly, that article says that a tiny fraction of simpler fossil fuels like natural gas may have an abiogenic origin. ) APL (talk) 05:19, 16 September 2013 (UTC)

All good points. I'd like to add that the first law of thermodynamics implies that even if we manufacture synthetic fuel (as e.g. Germany did in WW2 to produce fuel for tanks and aircraft), this is not an energy source, but only a means of energy storage and distribution. Indeed, the second law implies that we lose usable energy in the process. --Stephan Schulz (talk) 07:42, 16 September 2013 (UTC)

Technically true, but the energy source could be something that was going to be wasted otherwise, like farm waste or sewage we've exposed to genetically modified bacteria (to convert it to oil or fuel). Of course, this doesn't necessarily make it cheap, as you need to construct huge tanks for this fermentation, distill it to get the good stuff, deliver it, etc. StuRat (talk) 12:40, 16 September 2013 (UTC)

It's also worth pointing out that the problems that the world is facing are largely unrelated to "running out" of fossil fuel. The problem is the CO2 produced by consuming it. If we were to try to burn our remaining reserves of fossil fuels, we'd make the planet unlivable by humans long before we ran out of them. The (frankly, crazy) idea that new oil is being formed by some magical process or other is neither here nor there. A better heavenly body to look at is Venus - which ought to be a virtual twin of earth but because of a runaway greenhouse-effect is one of the more nasty hell-holes in our solar system!

Sadly, climate change (and "peak oil") deniers are becoming almost impossible to talk to in any rational manner because they are only too happy to simply refuse to see the data that's clearly available to all who care to open their eyes to it...they have to go into the same category as Apollo moon-landing deniers, Holocaust deniers, Homeopathists and flat-Earthers. SteveBaker (talk) 13:34, 16 September 2013 (UTC)

I am not sure about a couple of points of yours Steve. Imagine that we had already burned half the oil that is somehow available. That has provoked a temperature increase of 1.4 °F. What would happen if we burned the other half? Another 1.4 °F? Less than that? Or more than that? OK, global warming is happening, but maybe we can literally live with that. OsmanRF34 (talk) 16:53, 16 September 2013 (UTC)

Oil is one of the smaller parts of our fossil fuel reserves. It's important economically because it's cheap and easy to put in cars.

The big deal is coal and natural gas. APL (talk) 20:53, 16 September 2013 (UTC)

The world's oil reserves are hard to estimate. Our oil reserves articles says that we currently estimate 1,300 billion barrels of known reserves - plus 300 more in oil shales and sands, 510 more in the artcic...let's say 2,000 billion barrels in round numbers that could possibly be extracted. The world's annual oil consumption is around 80 million barrels per day - which gives us 68 years - assuming we consume neither more nor less oil than we are right now - and that we are clever enough to extract it economically from difficult places like oil shales and sands, bitumen deposits and from under the arctic ocean (which will get much easier when the North pole has melted!). I'd bet we'll find more reserves under the antarctic continent as the ice melts there too. However, that's just speculation.

Other fossil fuels will last much longer. There is about as much natural gas left as there is oil - and there is two and a half times as much coal.

Over the last 30 or 40 years, with about the same consumption rate we have now, we've added 0.8 degrees of warming (check out the first graph in Global warming) - if these effects were linear, then at present rate we would add around two more degrees of global warming over then next 68 years - making about 3 degrees total increase by the time the oil runs out.

But that makes two large (and unlikely) assumptions:

1. That burning X times as much oil as we already have will produce X times as much temperature increase.
2. That the current rate of oil consumption won't change until the day the last shovelful of oil sand is processed.

But we know for sure that there are several positive feedback effects that will cause the rate of temperature rise to increase as the world warms up:

• Melting the ice caps means that the earth reflects less sunlight out into space,
• As low lying areas are flooded by rising oceans, having a larger fraction of the earth covered with water means that we absorb heat faster.
• At some point, the deep ocean methane clathrates will melt, releasing an ungodly amount of methane will be released - and it's a far worse greenhouse gas than CO2.
• As permafrost melts, the peat bogs will start to decay, releasing more CO2.

etc, etc...so it's a little hard to predict how much worse than 3 degrees. Certainly we should expect more than a 3 degree increase if we continue as we are for another 68 years.

We also know that the oil won't run out that fast. Oil will get progressively harder to extract from these difficult places - the price will go up - so our reliance on gas and coal will likely increase - and the reserves of those are vastly bigger than the oil reserves. The oil won't actually "run out" (become economically infeasible to recover) until more like 150 years. If the other fossil fuels are used to fill the gap and our CO2 production rate continues unabated - we'd have a temperature increase more like 5 degrees by a straight "linear" assumption - and maybe much more than that if there are positive feedback effects - which would be pretty much "game over" for our civilisation.

For that reason, we have to cut back on all fossil fuel use LONG before we run out of oil. SteveBaker (talk) 14:11, 17 September 2013 (UTC)

Let's start from the basics. Hydrogen is the most common element in the universe. Exploding stars make lots of carbon, nitrogen, and oxygen. So planets like Earth and moons like Titan start out with a reducing atmosphere with lots of hydrocarbons, ammonia, and water (C, N, O each with as much H as possible). Now over time much of Earth's hydrogen has been lost to solar wind, so that there is more carbon dioxide and molecular nitrogen, etc.; but meanwhile the evolution of photosynthesis meant that plants could hoard carbon and hydrogen out of the atmosphere. The net result is that of all the original components of the atmosphere we are down to nitrogen, oxygen, some noble gas etc., and hydrocarbons seem scarce because everything wants them. Except where the plants' precious hoard is buried underground and cooked up chemically... the components of oil and of Titan's atmosphere are of course not exactly the same (for example the amount of ethane), but given the basics of what elements are available, there will inevitably be some similarities. Wnt (talk) 18:24, 16 September 2013 (UTC)

Atomic carbon in ISM

When was atomic carbon first detected in the interstellar medium? Plasmic Physics (talk) 07:31, 16 September 2013 (UTC)

Maybe 1980?[18] Thincat (talk) 08:13, 16 September 2013 (UTC)

Thanks. 1980 is too late, but the article gives Morton et al. (1973) as a possible date for earlier detection. Plasmic Physics (talk) 13:05, 16 September 2013 (UTC)

How can I work property rights for something ?

duplicate of question on humanities desk, see there. μηδείς (talk) 16:01, 16 September 2013 (UTC)

Are you believe general relativity theory ?why?

Are you believe general relativity theory ?why? — Preceding unsigned comment added by 37.238.39.250 (talk) 11:02, 16 September 2013 (UTC)

What does belief have to do with it? It's a fairly sound theory which has been confirmed by experiment. That is, things the theory tells us is true about the universe have matched observations. That's all that is needed for a sound theory. Belief has nothing to do with whether it is sound or not. --Jayron32 11:31, 16 September 2013 (UTC)

With any scientific theory, it has to pass four tests:

1. It has to explain all of the facts that whatever it replaces were able to explain. (It can)
2. It has to be compatible with whatever existing laws it does not replace. (It is)
3. And it has to produce predictions that can subsequently be tested. (It does)
4. It has to be falsifiable. (It is)

When all of those things are true - we generally accept the theory as "The Truth"...or at least "Our Best Idea Of What The Truth Is Right Now".

Our article Tests of general relativity lists many of the predictions of general relativity that have subsequently come true. One prediction of was that gravitational lensing sould occur. The first image at right here (taken by the Hubble space telescope) is of a gravitational lens (called an "Einstein Cross"). Another prediction was the existence of black holes - and evidence for the existence of one of those was found by the ESO's VLT from 2006,2010 and 2013 (second image at right). Many other tests have shown that this theory does indeed fit the facts of the observable universe.

Just like any other theory, it's possible for general relativity to eventually be proved incorrect - but to do so would require finding evidence outside the realms currently tested. The biggest issue remains that of how to reconcile general relativity with quantum theory. But consider that although Newton's laws of motion were eventually shown to be incorrect at high relative velocities and replaced by Special relativity - those laws are still useful and highly accurate approximations for most applications. If general relativity is proven wrong, it'll likely be in some extreme situation (such as at very small scales, where quantum theory rules) - and it's very possible that general relativity would continue to be used as an expression of the way the universe works at larger scales.

SteveBaker (talk) 13:23, 16 September 2013 (UTC)

I first saw the effects of going back in time like as De Ja vu, second , to add and subtract you need from any direction and therefore something missing — Preceding unsigned comment added by 81.218.91.170 (talk) 16:16, 16 September 2013 (UTC)

The only quibble I would have is with the statement "Our Best Idea Of What The Truth Is Right Now". It would be better stated as "Our Best Idea Right Now Of What The Truth Is". The Truth does not change. What changes is how much we know about The Truth. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:41, 16 September 2013 (UTC)

General relativity while very useful in cosmology, is known to be false as it is a classical theory. As SteveBaker points out above, it will break down at scales where quantum effects are important. But we don't have to wait for some experiment to falsify it, it is already falsified. Take e.g. the Hydrogen atom. A general relativistic description of the hydrogen atom is obviously in conflict with experiment. Count Iblis (talk)

Go on... Dauto (talk) 15:24, 16 September 2013 (UTC)

Neither General nor Special relativity says anything about going back in time. thx1138 (talk) 16:46, 16 September 2013 (UTC)

that say sameting abuot speed limit ? — Preceding unsigned comment added by 81.218.91.170 (talk) 17:14, 16 September 2013 (UTC)

The theory of special relativity says that nothing can travel faster than light - and that nothing that has mass while at rest can travel as fast as light. General relativity builds on special relativity...so yes, it does indeed say something about speed limits. SteveBaker (talk) 13:25, 17 September 2013 (UTC)

Woodward effect

Woodward effect seems to be too good to be true, because it promises us the way to create both reactionless drive and warp drive. So here is my questions.

1. Is this effect has been experimentally demonstrated? If yes, are they already exclude another possible force?
2. What implications could it bring to our space exploration?
3. Can we, at this stage, convince someone either a government, a private space company or kickstarter peoples to fund more research on this thing? If not, how?

140.0.229.26 (talk) 11:05, 16 September 2013 (UTC)

1) They claim it has been demonstrated, but the scientific community has yet to accept the results. Excluding other sources is the problem, as it was for cold fusion.

2) Huge implications, if it turns out to be true.

3) I suspect that most investors would want irrefutable proof that it can work before putting down major amounts of cash. StuRat (talk) 12:51, 16 September 2013 (UTC)

1. Is this effect has been experimentally demonstrated? - No. It says so right in the first paragraph of our article: "So far, no conclusive proof of the existence of this effect has yet been presented.".
2. What implications could it bring to our space exploration? - It's far too soon to speculate on that. Until it's been shown to actually work, we can't tell the engineering or economic cost of making one.
3. Can we, at this stage, convince someone either a government, a private space company or kickstarter peoples to fund more research on this thing? - The Woodward_effect#Results section of our article suggests that researches at a number of facilities (including on at NASA) have at least tried to replicate the experiment. Commercial space companies tend to stick to relatively proven technologies. They can't risk funds on something as blue-sky as this. Large-scale funding is unlikely until the existence of effect has either been clearly demonstrated - or the theory behind it has been widely accepted by the mainstream physics community.

Kickstarter would probably not accept this project. It would fall under their "Hardware and Product Design guidelines" (see http://www.kickstarter.com/help/guidelines) - which state "Projects must show details (photos, videos, sketches) of their progress so far, along with a prototype demonstrating the product's current functionality." - which would presumably be hard to achieve for a purely research project. However if you look at Comparison of crowd funding services, you'll see that several (eg Microryza, Petridish.org) are set up specifically to fund scientific research.

SteveBaker (talk) 13:02, 16 September 2013 (UTC)

To me the only way to conclusively proof that this is true is to slap this experimental thingy into a cubesat and hope for the best. However, no one wants to provide the funding for that, so its a chicken and the egg problem 140.0.229.26 (talk) 13:23, 16 September 2013 (UTC)

You are imagining that this thing is way more understood than it really is. Right now, the theory isn't anywhere remotely there - we don't know whether a practical drive would be the size of a grain of salt or twice the size of the moon - or anywhere in-between! The effect hasn't even been conclusively demonstrated yet. I would actually bet a good sized pile of money that it'll never work...it violates too many well-established scientific laws - and that's always a red-flag for any new device. What this needs is a white-board and a room full of physicists for six months...not physical machines...and certainly not physical machines that can be launched into the vacuum of space. SteveBaker (talk) 14:37, 16 September 2013 (UTC)

Seems like crackpot to me. Dauto (talk) 14:46, 16 September 2013 (UTC)

That's speculation, there is a line between crackpot and this sort of thing. OsmanRF34 (talk) 15:07, 16 September 2013 (UTC)

"Extraordinary claims require extraordinary proof" - and the idea that you can make a 'reactionless drive' is a highly extraordinary claim. So far, any "proof" has been exceedingly sketchy. So until we see some pretty darned extraordinary evidence, we should probably deploy occam's razor and ignore it. SteveBaker (talk) 16:20, 17 September 2013 (UTC)

Tritiated water

How much T₂O would someone have to ingest before the effects became noticeable? Double sharp (talk) 13:55, 16 September 2013 (UTC)

Acute radiologic effects, long-term radiologic effects, or isotopic effects? DMacks (talk) 13:57, 16 September 2013 (UTC)

Well, when does each "milestone" get reached? Double sharp (talk) 14:01, 16 September 2013 (UTC)

Bug identification

spyder like kind of bug?

What kind of bug is this?

Last night it was in my kitchen’s floor, and was fast as hell

Iskánder Vigoa Pérez (talk) 14:17, 16 September 2013 (UTC)

My best guess is that this is a type of Pseudoscorpion. --Jayron32 14:20, 16 September 2013 (UTC)

Where in the world is the photo taken? What is the span of the longest legs? This info will help us give better answers/guesses. Anyway, I think most pseudoscorpions are much smaller than that critter looks. My best guess is a type of "tailless whip scorpion", i.e. a member of the Amblypygi. SemanticMantis (talk) 15:02, 16 September 2013 (UTC)

i guess it was 4" or so... and was very fast

the foto was taken in Cuba, Artemisa — Preceding unsigned comment added by Iskander HFC (talk • contribs) 15:08, 16 September 2013 (UTC)

Thanks, that helps! I'm now pretty sure it is indeed a tailless whip scorpion.

Describing my process, in case anyone is interested:

1. Front "mouth parts" are just wrong for spiders, they seem to be pedipalps, not spider mandibles or fangs.
2. It is scorpion-like, but pseudoscorpions are too small (and tend to have more elongated body profiles), and Solifugae have other, stranger mouths.
3. Trying to guess common descriptions, I googled combinations of /flat crab scorpion/.
4. That led me to this nice page dedicated to tailless whip scorpions (with cute baby pics!) [19]
5. Back to WP, tailless whip scorpion has the right redirect, and I confirmed a few key traits: a)flattened body, solid carapace, with segmented abdomen b) elongated sensory legs, c) pedipalps used as prey catchers.

Hope that clarifies/ helps others in their weird critter ID process. SemanticMantis (talk) 15:19, 16 September 2013 (UTC)

• Yes, it's a whip spider. Pseudoscorpions are very small; I found one crawling on my mother after she was gardening, and, unfortunately, killed it thinking it was a tick. μηδείς (talk) 15:52, 16 September 2013 (UTC)

In the way it moved resembled more a cockroach than a scorpion or a spider

Certainly it isn’t any of the ones pictured in the articles… maybe similar to the tailless whip spiders

Iskánder Vigoa Pérez (talk) 16:47, 16 September 2013 (UTC)

Yes, they are fast, and might move sideways. Your pic looks a lot like this one [20], which is Phrynus_marginemaculatus. SemanticMantis (talk) 16:56, 16 September 2013 (UTC)

It's Amblypygi for certain, but they all look very similar. Looie496 (talk) 16:59, 16 September 2013 (UTC)

Mycoremediation of Sarin

In his 2005 book How Mushrooms Can Help Save the World; Mycologist Paul Stamets states certain classified species of mushrooms can bio-remediate Sarin; a statement he made previously in the magazine Whole Earth in 1999. Here it is used as a reference by the UNC Institute for the environment dated 2009. http://www.ie.unc.edu/for_students/courses/capstone/09/owasa_final_report.pdf Would this information be appropriate to add to the article on Sarin? Paul Stamets is the one who coined the term mycoremediation, and the research is difficult for civilian scientists to peer review as it is now classified. CensoredScribe (talk) 16:13, 16 September 2013 (UTC)

how to isolate the Acetylsalicylic acid from the white willow (salix)?

If I have a little branch of white willow and I want to isolate the Acetylsalicylic acid from the tree, how can I do it? or how can I take it off from the willow without destroy it? (in example to boil it in water or something) 95.35.250.74 (talk) 19:35, 16 September 2013 (UTC)

As far as I know, willow bark has no (well, maybe almost no) acetylsalicylic acid per se. It has salicyclic acid, without the acetyl group.

I remain somewhat confused on this point. Our aspirin page claims, or has claimed, that aspirin works by irreversibly acetylating COX, which salicylic acid obviously can't do (no acetyl group). So is the similar (though less potent) action of natural salicylates just a coincidence? I've never gotten the straight story on this. --Trovatore (talk) 19:40, 16 September 2013 (UTC)

Methyl salicylate is also a known pain reliever, and claims are made in that article (with refs) that the body does metabolize it and other salicylates into Acetylsalicylic acid. The Salicylic acid article itself also notes its pain relieving and fever reducing properties. --Jayron32 20:06, 16 September 2013 (UTC)

"Metabolize" is an odd word to use in this context — apparently you mean the body acetylates the salicylates? Why does it do that? Is it an instance of a general detoxification strategy or something? --Trovatore (talk) 20:33, 16 September 2013 (UTC)

I don't see any claim about acetylation in the methyl salicylate article. To be clear, plain salicylic acid was discovered first. Then people realized it was burning holes in their stomachs, so they figured they could neutralize it a bit by acetylation (I think - the chemistry beliefs of the time were confused, but preparations like 'Bufferin' reflect the belief that the acid was the problem). The aspirin really did cause less stomach upset, though the protection given by the acetyl ester is inferior to that of natural glycoconjugates that had been used for at least five millennia before the marvels of modern chemistry... Anyway, getting back to the point, anything on that phenolic OH comes off, sooner or later, and the same is true for the willow salicylates. You can study them by something like this (grind up in water:methanol:chloroform, purify/assay by HPLC) - however, if your intent were just isolate a preparation for use, any complex lab work should be avoided, since the willow contains other active compounds besides salicylate [21] and using a standard herbal preparation method listed in a reputable pharmacopoeia, in accordance with local regulations, is just safer overall. Wnt (talk) 21:03, 16 September 2013 (UTC)

Oh, and metabolize would have been the right word, as it encompasses both anabolism and catabolism. Wnt (talk) 21:05, 16 September 2013 (UTC)

Well, that may have been what people thought they were doing by acetylation. However, if aspirin's primary mode of action is that it acetylates COX, then it would seem that the actual effect of acetylating salicylic acid is that it provides an acetyl group that can then be transferred to COX. Unless as Jayron says the salicylates get acetylated in the body anyway? But I don't see that in the link he gave either. --Trovatore (talk) 21:09, 16 September 2013 (UTC)

Hehe, biology likes to play tricks on scientists! Aspirin will indeed inhibit COX in vitro by acetylating it. But when consumed, aspirin is quickly converted back to salicylate. The salicylate, it turns out, somehow manages to prevent transcription of COX enzymes by some other means. [22] (I wonder if it is mimicking one or more endogenous compounds which have had the time to evolve a complex regulatory biology) Wnt (talk) 01:01, 17 September 2013 (UTC)

Hmm, well, our articles on aspirin and mechanism of action of aspirin still claim that it works by acetylation. Not my field; I couldn't say. --Trovatore (talk) 01:08, 17 September 2013 (UTC)

That proof "negative time negative equal positive" is wrong|What would happen if proved wrong proof ?

I have a proof on this but I know proof "negative times negative equal positive"

this is

according to proof wrong

-(-a)=a

-(-a)+0

-a+a=0

-(-a)+(-a+a)

-(-a)+(-a)+(+a)

-(-a)+(-a)=0

0+(+a)

=a or +(+a)

this is wrong ObaidNgers (talk) 20:01, 16 September 2013 (UTC)

You may be better off asking this at the Mathematics desk. --Jayron32 20:03, 16 September 2013 (UTC)

"doesn't make any sense" may be more accurate than "wrong". 86.160.214.202 (talk) 20:55, 16 September 2013 (UTC)

Nah, the first line is a valid statement; the second equality contains an error; the third equality is valid but is just an expansion and proves nothing byond what is already given. 1.122.109.132 (talk) 00:27, 17 September 2013 (UTC)

I don't understand the "proof" above - there are missing equals signs and who-knows-what else.

It's very hard to construct a "proof" of this because the very rules of algebra assume that you can say things like:

1. a = a
2. -a = -a
3. --a = a
4. -(-a) = a
5. -1.-a = a

Which "proves" that if a is a positive number than (-1).(-a) is also positive - so negative times negative must be positive. But all that really demonstrates is that the algebraic operation of converting --a into (-1.-a) is legal - which makes the assumption that a negative sign implies a multiplication by -1. But that's only true if negative-times-negative makes positive and that --a = +a ...all of which would be untrue if negative-times-negative isn't positive.

So it's hard to "prove" that a fundamental mathematical operator like 'x' works that way.

In algebraic systems where the concept of multiplication isn't commutative (such as when multiplying matrices) the rules are different.

The consequences of this rule being untrue in basic arithmetic would be a paradox - and the Principle of explosion says that if you assert a falsehood then everything can be proven to be both true and false. If you can show that if (-1 x -1) = -1 then you can use that to prove that Santa Claus exists. (No, really! The proof is in Principle of explosion!)

SteveBaker (talk) 16:06, 17 September 2013 (UTC)

Mountains in Norway

Why are there mountains in Norway when there is no tectonic plate edges or volcanoes near? — Preceding unsigned comment added by 88.193.85.124 (talk) 20:19, 16 September 2013 (UTC)

I started at Mountain ranges of Norway, and then went to Caledonian orogeny and Geology of Norway.

Short answer: there used to be plate boundaries there. SemanticMantis (talk) 20:35, 16 September 2013 (UTC)

And surely glaciation must have played a role, by scraping the valleys deeper, thus making the mountains taller, relative to the valley/fjord floors. StuRat (talk) 06:47, 17 September 2013 (UTC)

Much of Scandinavia was close to sea level at the end of the Cretaceous. Since the Late Paleocene there has been dramatic uplift, modified more recently by glacial erosion and unloading. The cause of this uplift is still not well understood, although it may be to do with the peripheral effects of the opening of the North Atlantic at the end of the Paleocene (and therefore a plate boundary related process). This is discussed here, but I'll try to find some more references this evening. Mikenorton (talk) 07:08, 17 September 2013 (UTC)

Variable power supply plug

I have one of these switching power supply plugs. What is likely to happen if the resistance of the load is insufficient to limit the current to less than 1A? The plug has a CE mark, so presumably meets minimum requirements for safety in the UK. Does that mean a mechanism inside the plug stops the current from going past 1A and limits the voltage accordingly? — Preceding unsigned comment added by 78.150.23.174 (talk) 21:14, 16 September 2013 (UTC)

Yes there is. 24.23.196.85 (talk) 23:23, 16 September 2013 (UTC)

While the voltage may drop on heavy load, it may or may not drop sufficient to limit the current to one amp. The manufacturer does not claim or indicate that any overload protection circuit is inside. As with plug packs in general, you should assume that exceeding one amp will overload it and damage it. Note that such damage may or may not occur immediately, it may require a long period of operation or may only occur at high ambient temperatures. However, safety aspects, such as fire or electric shock hazards, arising as a consequence of overload damage are should be unlikely. I say "should be", as CE marking is a self-certifying scheme and thus subject to a certain amount of abuse, ignorance, and plain oversight by manufacturers, particularly the less well known far east manufacturers. 1.122.109.132 (talk) 00:17, 17 September 2013 (UTC)

Okay, thanks. If I'm interested in electronics as a hobby, at what point would I need to a power supply more like this one? In what ways would I be limited by using that plug in lieu of a regulated supply? (maybe I won't cross that threshold and therefore don't need the regulated supply) 78.150.23.174 (talk) 03:54, 17 September 2013 (UTC)

The power supply you linked is a basic labaortory unit. As to what stage you will need to consider a lab supply is just about impossible to answer. There is such an enormous range of things in electronics you can do, and such an enormous range of ability that beginning hobbyists have, and how far they'll go. A lot of hobby projects published in magazines and elsewhere are designed to use plug-packs ("wall warts" in America) or batteries, because it simplifies things and completely removes any concerns about electric shock hazards and fire safety.

I became interested in electronics at age 9, and by 12 years of age I had succesfully built a vast number of radios, walkie-talkies, burglar alarms, and gadgets like soil moisture meters without ever thinking of powering them from anything other than a 9 volt battery. When I moved on to building things like high power stereo systems, I had enough knowlege to build my own power supplies in complete safety - part of the fun. Probably the best advice I can give, without a long discussion with you to find out what you expect to do in your new hobby, is this: Don't buy a power supply of any type beyond a simple plug-pack until you know you need it, you understand why you need it, and the cost is simply not an issue for you. Or, to put it in another way, when you definitely need a lab supply, you'll know - you won't have to ask.

However, the posession of a laboratory variable power supply, together with a range of instruments (multimeters, oscilloscopes, signal generators) will assist you in doing a range of basic and fundamental experiments that will help advance your electronics theory knowlege, should you be that way inclined. One can choose two ways to go early in a hobby, especially in analogue electronics as distinct from microcomputers. You can go for developing a good fundamental knowlege of theory (like an engineer), or you can go for building things out of kits or magazines without really understanding how they work (somewhat like a technician), and why the designer did things a certain way. Both paths can be very satifying. The first path requires a greater commitment in time and money for a given quantity of things to impress non-technical friends.

1.122.41.205 (talk) 05:24, 17 September 2013 (UTC)

Relationship between knowing how to touch-type and electronic test scores?

Is there a relationship or correlation between knowing how to touch-type (that is, typing without looking at the keyboard) and doing an online exam? I predict that people who know how to touch-type have more time spending on the material than they do typing; therefore, they may receive better scores on tests. Though, it doesn't hurt to learn what the research says. 164.107.103.68 (talk) 21:42, 16 September 2013 (UTC)

I'm not aware of any research, but offer the following factors that will reduce or eliminate any linkage: Firstly, online exams should be designed so that bulk typing of text is not required. In many cases, exams are multi-choice, so intead of ticking boxes on paper, you are clicking on screen boxes with a mouse. If the exam is an engineering or science subject, touch typing as taught by secretarial schools won't help much, as they teach what works well with business letters, not science/engineering. Touch typing relies on a rhythm to get speed that sceince and engineering typing tends to stuff up. In exams, you will likely be doing a lot of mousing, for which touch typing has no relavence. Mousing stuffs up touch typing rhythm. Lastly, I found that after using PC's for about 5 years, without any typing training, that while I only graduated from "two-fingered hunt & peck" typing to actually using about four fingers, on ordinary business typing I can keep up with almost all "office girl" types who have been trained in touch typing. On on typing scientific bulk text, I run the pants off them, on both speed and accuracy. We use a lot of multi-syllable specialised terms in science and engineering and they can't cope with it. University academics and doctors employ specialist typists for this reason and pay them more money than the ordinary office girl gets. But even they can't go that much faster, though they are considerably better in accuracy. My secretary/PA is as good a worker as any in industry, and on ordinary business letters goes very quick. But watching her type up a service manual is very painfull. On sentences such as "Remove the widget cover by undoing the four screws and tilting to the left." she goes like the clappers and does a perfect job. But on stuff like "Using the HP 8556 spectrum analyser, adjust the bandpass filter inductor slugs to peak the amplitude response in order to the frequencies listed in Table 6.10", she goes almost letter by letter slowly and makes lots of mistakes. 1.122.109.132 (talk) 01:28, 17 September 2013 (UTC)

I expect that people with touch-typing skills are more likely to be computer-literate, as well, so might do better on any exam where computer literacy is either being tested intentionally, or unintentionally. StuRat (talk) 06:45, 17 September 2013 (UTC)

You can also use voice to text facilities of your I-phone or PC. If it is fine tuned to recognize your voice and has a suitable library for common words for the particular subject matter, it works quite well. Count Iblis (talk) 11:46, 17 September 2013 (UTC)

Aren't most online tests of the multiple-choice variety? Touch-typing won't really help when it's largely mouse-clicks. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:35, 17 September 2013 (UTC)

September 17

Cattle teeth and bones

After they kill a cattle for its meat and skin, do they use the teeth and bones for anything, or are they just discarded? ScienceApe (talk) 00:00, 17 September 2013 (UTC)

See bone meal. --Jayron32 00:08, 17 September 2013 (UTC)

Marrow and cartilage are used for gelatin and broth. μηδείς (talk) 00:52, 17 September 2013 (UTC)

What study is being cited?

In this from the Daily Mail, it is said "one study in which a group of patients were given a saline solution which they were told could be chemotherapy. Despite the fact it was only salt water, 30 per cent of the patients lost their hair". Does anyone know what study the book Mind Over Medicine is citing? Thanks. Biosthmors (talk) pls notify me (i.e. {{U}}) while signing a reply, thx 07:56, 17 September 2013 (UTC)

@ Biosthmors (talk · contribs) This "fact" seems to be bandied about casually all over the place without a source, but I found a mention on this page that looks like it's citing the same study. If so, it's Fielding, J.W.L. "An Interim Report of a Prospective, Randomized, Controlled Study of Adjuvant Chemotherapy in Operable Gatric Cancer: British Stomach Cancer Group." World Journal of Surgery 7 (1983): 390-99. I don't have access to check whether it's the right one or not. - Karenjc 11:46, 17 September 2013 (UTC)

Looking at the full text, the reported incidences of "alopecia" were 74% and 49% in the two drug treatment arms of the study, and 30% in the placebo arm. Severity isn't discussed—we don't know how much hair loss occurred. (Alopecia can refer to partial or total hair loss.) Further, all patients – in both drug arms and in the control arm – had major, recent surgery to remove gastric tumors. In the words of the study authors,

"Analysis of the toxicity associated with chemotherapy, though confirming its more frequent occurrence in the treated patients, also demonstrates that there are significant "toxic" effects in the control group which must be attributable to either the placebo effect, the underlying malignancy, or the operative procedure."

While the paper didn't explicitly address this point, it's also worth noting that about two-thirds of the patients were over age 60, and about two-thirds of the patients were male: populations expected to see naturally-occurring hair loss even under normal conditions. In other words, it is an open question how much of the hair loss could be attributed to genuine 'placebo effect', versus the physiological and psychological stresses of serious cancer and major surgery, or the natural properties of a mostly-male, mostly-older patient population. Baldly declaring that all of the hair loss in the placebo group was due to the placebo effect (and sweeping all the other contributing factors under the rug) is an interpretation that isn't justified by the paper's actual data or conclusions.

To actually measure the potency of the placebo effect here, the study would have needed a fourth arm, in which the patients did not receive any injections. (Or, even better, where the patients receiving saline were told explicitly that it was just inert saline not expected to have any effect whatsoever.) Good luck getting ethics committee approval for that one, though. TenOfAllTrades(talk) 14:42, 17 September 2013 (UTC)

Liberty + mental health

Why do people exist who strongly oppose personal liberty? For instance, there are people out there who strongly believe we should legally limit the personal freedoms of transexuals to choose their own name. Do such people have brain pattern differences? Any research on this? Pass a Method talk 08:39, 17 September 2013 (UTC)

The difference is often a cleaner brain caused by irrational adoration of a leader. HiLo48 (talk) 09:59, 17 September 2013 (UTC)

What about the legal limits on heterosexuals to choose their own name? They are the exact same limits. 1.122.41.205 (talk) 11:08, 17 September 2013 (UTC)

But why don't these groups oppose name changes by heteros? Why only oppose name changes by trans people? Double standards. Pass a Method talk 12:15, 17 September 2013 (UTC)

Convicted criminals don't necessarily get to do as they please. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:33, 17 September 2013 (UTC)

I don't see any connection between transgender individuals and convicted criminals. An unusual parallel to draw. Liz ^{Read! Talk!} 12:55, 17 September 2013 (UTC)

It is reasonable to assume that the OP's question was prompted by the Bradley Manning vs. Chelsea Manning Wikipedia article title change debate, and while the OP phrased the question more generally, BB is certainly referring to that specific case, and not to transgender people in general. -- ToE 13:53, 17 September 2013 (UTC)

Yes, that was my assumption. By contrast, I don't recall there was any significant outcry over Chastity Bono becoming Chaz Bono. The bigots are going to hate it no matter who it is. But as a legal matter, I don't think there's anything stopping someone like Chastity/Chaz Bono from getting a name change. The Manning case has to do at least in part with a lawyer negotiating for a different prison from Leavenworth. Hence the cynicism about that situation. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:20, 17 September 2013 (UTC)

Just a side note on wording - hetero isn't really the opposite of trans, as it describes sexual orientation rather than gender. A trans person can be heterosexual. Cissexual is often used within the community to mean someone who isn't trans or genderqueer in any way, but I haven't seen it used much outside of circles that discuss trans issues in a positive light and I wouldn't expect the average person to know what it means. Usually I use "not trans" in general conversation when I need an opposite. Don't worry - I don't think you're being offensive, you're clearly supportive of trans people so I figured you would like to know that the language you were using wasn't quite accurate. Katie R (talk) 13:45, 17 September 2013 (UTC)

I think the word you're looking for is Bigotry. 196.214.78.114 (talk) 12:59, 17 September 2013 (UTC)

Do you, the OP, oppose the liberty of serial killers to continue killing people? If so, why do you want to legally limit the personal freedoms of serial killers by putting them in jail?

My guess is that you'll argue that although personal freedom is good, murder is highly immoral and detrimental to society, so restricting a murderer's freedom is better than letting him go free. The same logic applies if you see transsexualism as immoral and detrimental to the sanctity of the family. It doesn't matter if this opinion is correct--if it is correct, it follows that restricting a transsexual's freedom for the greater good might be justified in the same way that restricting a murderer's freedom is justified. --Bowlhover (talk) 13:12, 17 September 2013 (UTC)

But the concept of "sanctity of the family" should be formally defined. If you were to attempt to give a formal definition of this, you would probably end up having to argue in a circular way. Count Iblis (talk) 13:17, 17 September 2013 (UTC)

The Bible explicitly prohibits both homosexuality and transsexualism. I'm sure you know as well as I do which passages prohibit the former. For the latter: "The woman shall not wear that which pertaineth unto a man, neither shall a man put on a woman's garment; for all that do so are abomination unto the Lord thy God" (Deuteronomy 22:5).

If you define a "sacrosanct" individual/family as one that does not explicitly violate God's law, as (supposedly) revealed in the Bible, transsexualism is definitely out. Deuteronomy is the same book containing the Ten Commandments (well, Exodus does too), one of which is "thou shalt not kill", so my analogy with serial killers is appropriate: if a Christian believes that his morality comes from the Bible, it makes perfect sense to put transsexualism/homosexuality in the same category as murder, as both violate God's law and are therefore immoral. --Bowlhover (talk) 14:01, 17 September 2013 (UTC)

Of course, by the same logic, eating bacon is also equivalent to murder since "The pig is also unclean ... You are not to eat their meat or touch their carcasses" (Deuteronomy 14:8). Gandalf61 (talk) 14:31, 17 September 2013 (UTC)

Because it would be too confusing if we changed half the article titles of List of people claimed to be Jesus to Jesus Christ? People can choose their names. They can't choose our article titles. We choose our article titles in order to make the best encyclopedia. That's often the same as the person's name, but not always. --GRuban (talk) 14:23, 17 September 2013 (UTC)

A reminder to all that this is a reference desk, not a forum for opinions or debate. Our articles on authoritarianism and conformity contain sections on psychological studies about these ideas and behaviors. I also recall reports of a study that found differences between "brain patterns" in U.S. conservatives and liberals. (Conclusions about "liberty" within these ideologies are your own to make.) Try googling those keywords (my workplace internet access is limited). 198.190.231.15 (talk) 14:34, 17 September 2013 (UTC)

(ec) Back to the OP's question - there's probably an f-MRI study on it. It seems like there is one on everything, not that it will prove anything - there is a lot of controversy on the usefulness of f-MRI studies on these sorts of subjects. I skimmed [23], and although it focuses on race it looks like it could be interesting to you. Katie R (talk) 14:38, 17 September 2013 (UTC)

"there are people out there who strongly believe we should legally limit the personal freedoms of transexuals to choose their own name." Where is the evidence here? There are bigots of all stripes, but I'm not sure what the point of the question is. Also this doesn't seem like a reference desk post, it seems like a personal forum debate about naming of trans* people. --Obi-Wan Kenobi (talk) 15:56, 17 September 2013 (UTC)

I read the question as asking if there has been any scientific research into why bigotry exists. That's why I linked the article on research on subconcious prejudices in race. I cringed when I read the question because I worried it would go down the personal opinion/forum route (especially due to using the current hot topic of trans naming as an example), but I think the question itself is something we can answer and provide references for. If you want to discuss the validity of the question further we should probably move to the talk page. Katie R (talk) 17:10, 17 September 2013 (UTC)

Ok thanks Katie. If you can steer this back to answer the broader topic, eg what are the scientific basis of bigotry for example, then it will be illuminating, and I hope we'll keep other discussion off this thread as it's not ontopic.--Obi-Wan Kenobi (talk) 17:19, 17 September 2013 (UTC)

• Given where this thread has been linked (e.g. Talk:Alexis Reich in a move request and User talk:StAnselm), this comes across as a thinly veiled attack on certain editors. The Reference desk is not a forum or a way to circumvent conventional talk page guidelines against soapboxing. -- tariqabjotu 17:05, 17 September 2013 (UTC)

Closest relative commonly eaten by humans

Discussing birds eating birds the other day, the question arose "Of the animals commonly eaten by humans, which is the most closely related to us?" For the purposes of this question, let's ignore any primates. Any decent notion of relatedness is OK, be it most recent common ancestor, or number of degrees of separation in a standard taxonomy. Thanks! SemanticMantis (talk) 16:27, 17 September 2013 (UTC)

My best guess is Philippine flying lemur, depending on if it meets your definition of "commonly eaten." The article says their meat is eaten as a delicacy. They're not true lemurs, and aren't primates. Based on Euarchontoglires#Organization I don't think you can get any closer without being a primate. Katie R (talk) 16:51, 17 September 2013 (UTC)