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February 10

clay

is it true that ceramic dinner plates have crushed glass added to the clay?--Tomjohnson357 (talk) 02:33, 10 February 2011 (UTC)[reply]

Some might. --Jayron32 03:49, 10 February 2011 (UTC)[reply]

Well, by that reasoning, "some might" have just about anything added to the clay. We do have an article on Ceramic which seems to indicate that crushed glass is not a necessary, or even common component of ceramic. In fact, it also states that for modern ceramics, even clay is not a necessary component. The relevant article is Ceramic materials which further states Glass by definition is not a ceramic because it is an amorphous solid (non-crystalline). Vespine (talk) 04:04, 10 February 2011 (UTC)[reply]

Or are you asking if plates that are "advertised" as ceramic sometimes adulterated with crushed glass? I have no answer for that question. Vespine (talk) 05:26, 10 February 2011 (UTC)[reply]

On the other hand the Ceramic article states: "Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous (e.g., a glass)". And Porcelain directly attributes some of the properties of porcelain to glass formation.

Also, is it even relevant for the finished product whether the original mixture included glass powders? If I understand correctly, the components of the body will partially melt and re-crystallize during firing anyway, and the final structure generally consists of crystalline particles held together by a glassy matrix.

The soft-paste porcelain article mentions that ground-up glass has been used in porcelain formulations. –Henning Makholm (talk) 10:32, 10 February 2011 (UTC)[reply]

My understanding from googling around a bit is that there are some special ceramics that incorporate crushed glass because it gives them a distinctive quality -- ceramic tiles seem to be the most common use. Looie496 (talk) 17:23, 10 February 2011 (UTC)[reply]

Are ceramic dinner plates fired at a high enough temperature to melt any crushed glass that may be added to it? --70.167.58.6 (talk) 19:39, 10 February 2011 (UTC)[reply]

Silicon dioxide is the basic substance of glass. It may be found naturally in clay samples containing quartz. ~A H 1^(TCU) 22:26, 11 February 2011 (UTC)[reply]

crude oil

why price gap between WTI crude oil and BRENT crude oil is widening ?? —Preceding unsigned comment added by 121.245.239.36 (talk) 09:06, 10 February 2011 (UTC) :The ansewer is in the field of Economics, not Science, your question is in the wrong place. Roger (talk) 09:17, 10 February 2011 (UTC) [reply]

Yeah, that's why they call Economics the "dismal humanity". 109.128.101.244 (talk) 11:39, 10 February 2011 (UTC)[reply]

We don't have an economics reference desk Roger. ScienceApe (talk) 14:50, 10 February 2011 (UTC)[reply]

While there are economic factors which affect pricing (such as the 2007 oversupply of WTI at the facilities in Oklahoma), there are "science-y" factors as well. One being that all oil benchmarks are declining in production volume and actual deliveries are often in other oil blends at fractionally related price points. WTI has a premium over Brent because it is lighter and sweeter. If I am actually getting heavy, sour oil now for Brent-related prices, my processing costs increase and gasoline/diesel fractions yield decreases and Brent value decreases so the WTI/Brent gap should increase. If some extra-light, super-sweet Canadian oil sands (?) come on the market, WTI should increase in value, etc. See also Benchmark (crude oil), Price of petroleum, West Texas Intermediate, Sweet crude oil, Light crude oil, etc. Rmhermen (talk) 17:39, 10 February 2011 (UTC)[reply]

No but we do have a humanities and a misc desk, the Wikipedia:Reference desk specifically mentioning humanities as covering economics. Nil Einne (talk) 07:20, 11 February 2011 (UTC)[reply]

So all questions about Nash equilibrium across directed scale-free networks of ideal agents should be directed to the Humanities desk? If you don't know, don't answer, and don't bite. SamuelRiv (talk) 19:16, 12 February 2011 (UTC)[reply]

Price for quantitative analysis of chemical elements

Say I have 1g of a substance and I want to know which elements are contained in what quantities. I'm not interested in molecules or cristall structures or such. As result, I want to have a list that reads, for example, like this: C 400mg, O 150mg, N 30mg, H 20mg, S 3mg, Si 2mg, .... Ni 3µg, As 1.2µg etc. . How much would such an analysis cost and which methods would be used? 77.3.134.134 (talk) 10:20, 10 February 2011 (UTC)[reply]

Depending on the accuracy you need it could be very cheap. Energy-dispersive X-ray spectroscopy would be the trick for every thing in down to the 1% range. Going down to ppm it is expensive.--Stone (talk) 10:32, 10 February 2011 (UTC)[reply]

Five percent for each amount (factor 0.95 to 1.05, not percent of the total sample mass) would be fine. What, approximately, would mean "cheap" in this context? 77.3.134.134 (talk) 10:52, 10 February 2011 (UTC)[reply]

The general field is elemental analysis. That article mentions several methods. There are many companies that will do contract-work analysis of customer samples--a quick google or business-directory search involving the (quoted) phrase might find some with rates posted (or at worst, would give a ballpark over the phone/email) for various levels of accuracy. DMacks (talk) 15:18, 10 February 2011 (UTC)[reply]

Metallurgical assay is also used in some circumstances. ~A H 1^(TCU) 22:24, 11 February 2011 (UTC)[reply]

I work in a mineral assay lab. ICP-OES can analyze 30-40 different elements down to sub-ppm levels for around $25. This will handle most of the transition metals but doesn't include "organic components" like C, H, N, O. 142.179.81.220 (talk) 10:28, 12 February 2011 (UTC)[reply]

biology

what is the function of crop sac fluid in pigeon? —Preceding unsigned comment added by 180.215.15.1 (talk) 12:36, 10 February 2011 (UTC)[reply]

We have a article on Crop milk! Is this enough info? --Stone (talk)

I've added a few disambiguation links for crop sac related terms, so hopefully they'll autocomplete or turn up in searches now. We should remember that the word "disambiguation" is generally unknown to people unfamiliar with Wikipedia. Wnt (talk) 18:19, 10 February 2011 (UTC)[reply]

Cells in chicken eggs

When a chicken egg pops out of a chicken, how many cells does it have in it? I do not believe that it can be just one giant cell, as some people seem to think. Thanks 92.29.122.239 (talk) 13:04, 10 February 2011 (UTC)[reply]

Would you believe 2? Or, if not 2, then -- since, to be fair, the egg is a single cell -- what is the lowest number of cells you will accept as an answer? 109.128.101.244 (talk) 15:18, 10 February 2011 (UTC)[reply]

Don't be rude. This person has come to the reference desk to confirm a surprising factoid. If you can't offer a reference that answers the question kindly don't post anything at all. APL (talk) 15:26, 10 February 2011 (UTC)[reply]

He says that he "do not believe that it can be just one giant cell." So, I would like him to tell me what is the smallest number of cells he believes it can be. I could also have asked him why he believes it can't be just one cell, but the reasons don't concern me as much as the end result: what is the smallest number of cells that he believes it can be? 109.128.101.244 (talk) 18:06, 10 February 2011 (UTC)[reply]

Yep, just one. --Sean 15:40, 10 February 2011 (UTC)[reply]

That says "there is only one cell in a unfertilized chicken egg and the rest is by definition of what an is an egg". What does "what an is an" mean? It also links to the Jehova Witnesses website. It also implies that the egg is not a giant cell, but a small (?) cell with a lot of something else filling up the egg. 92.29.122.239 (talk) 21:20, 10 February 2011 (UTC)[reply]

Egg yolk discusses this a little. The egg yolk does indeed represent a single cell. (The only cell in the egg.)

In some species of eggs the zygote and the yolk are separable, but even then what you've got is a single cell and a lifeless sack of yolk, not a multi-cellular egg. APL (talk) 15:43, 10 February 2011 (UTC)[reply]

Occasionally a chicken egg will have more then 1 yolk, but it is not all that common. Googlemeister (talk) 15:58, 10 February 2011 (UTC)[reply]

Just to clarify, while it's extremely uncommon to find one in the carton you get from the supermarket, the frequency of double-yolk eggs is much greater than you would expect from a supermarket experience. That's primarily because the eggs are candled prior to sale, and the ones with multiple yolks or other defects are removed. Afterward they're sold to bakers or manufacturers of liquid eggs, who don't care about appearance. -- 174.24.195.38 (talk) 17:03, 10 February 2011 (UTC)[reply]

Are double yolks undesirable to customers, then? (I don't have much egg experience.) Vimescarrot (talk) 17:26, 10 February 2011 (UTC)[reply]

Apparently any kind of variability is undesirable. If you keep chickens at home you'll find eggs of many shapes, sizes, colors, textures, etc. Some chickens lay blue or green eggs and I've never seen those from the egg factories. --Sean 17:38, 10 February 2011 (UTC)[reply]

Only a couple chicken species are used for mass-produced eggs. They are bred for standardization. --Mr.98 (talk) 18:56, 10 February 2011 (UTC)[reply]

I think we're missing the point of the question - you've answered that the egg/yolk is defined to be a single cell. But if fertilized, then 21 days later a chicklet pops out, which is obviously billions of cells. OP is asking how 1 is possible when billions result.

The key is in that statement - if fertilized. As you may know, OP, the eggs you eat only come from the mommy, and thus can never have a mini-bird inside. However, the eggs that actually produce new young have to come from insemination by a rooster, thus we have a sperm cell fusing with the egg, so now the egg has two. As with human embryos, the cells divide exponentially fast, and so within 3 weeks we can indeed have our chicklet with its billions of cells. And of course you can eat that too (the chicken embryo, not the human one).

~~One analogy is that the unfertilized egg we eat is just like a woman's menstruation (which releases a single egg cell)~~thanks Jay, but as chickens aren't mammals, this is not accurate. Can someone help find a better conceptualization? SamuelRiv (talk) 18:27, 10 February 2011 (UTC)[reply]

There is no good analogy. The menstruation analogy is so poor as to be misleading and should be avoided. The chicken egg is not an ovum, though it contains the ovum. There is no analogous package in humans, really. Its best just to explain the structure of the egg; it really isn't all that complex that an analogy would be required anyways. Making the analogy to menstruation, IMHO, actually makes the situation more confusing than just explaining the chicken egg on its own terms. --Jayron32 18:35, 10 February 2011 (UTC)[reply]

He asked about when the egg pops out of the chicken, not when the chicken pops out of the egg. APL (talk) 19:02, 10 February 2011 (UTC)[reply]

When the unfertilized egg pops out of the chicken, it contains one cell, the ovum, though as noted the ovum itself is much smaller than the egg, and is only part of it. When a fertilized egg pops out of the chicken, I am pretty sure it already has multiple cells within it, because the eggs are fertilized before they are laid, and cell division generally begins almost as soon as fertilization occurs. --Jayron32 19:26, 10 February 2011 (UTC)[reply]

I cannot believe that it is just one giant cell as a cell that big would not be able to respire. Normally cells are tiny and the ratio of surface area to volume allows the diffusion of gases such as oxygen and carbon dioxide. But a cell the size of a chicken egg would suffocate and die, as the relevant gases could not diffuse in or out fast enough. If there is just one tiny cell somewhere in a mass of "something else", then what is the "something else", and what is the membrain that keeps the yolk and white seperate made out of, and how did this membrain form? People may have been led astray by imagining that the yolk is the nucleus of a giant cell, but I do not believe that. This http://www.ncbi.nlm.nih.gov/books/NBK10070/ describes cells in the egg in the plural, but does not mention what happens or how far it goes in an unfertilised egg. Thanks 92.29.122.239 (talk) 20:38, 10 February 2011 (UTC)[reply]

Is an unfertilised hen's egg alive? It can't reproduce by itself, so the answer should be "no". Therefore your premise that "a cell that big would not be able to respire" is incorrect, as an unfertilised hen's egg doesn't need to respire. --TammyMoet (talk) 21:28, 10 February 2011 (UTC)[reply]

Just in passing, the ability of something to "reproduce by itself" is a very bad guideline for determining if something is alive. Your heart, your hand, your brain, your liver, a eunuch (indeed, one fertile male human or one fertile female human) all can't reproduce by themselves, and yet all are unequivocally alive. - Nunh-huh

Isn't the ovum in a hen's egg a haploid gamate? If so (like human egg cells/sperm cells) it is alive, but it doesn't undergo mitosis (division/asexual reproduction) until it fuses with a sperm to form a normal diploid cell. (Although bee drones are haploid and their cells divide. CS Miller (talk) 22:10, 10 February 2011 (UTC)[reply]

Perhaps you mean gamete, rather than gamate? DuncanHill (talk) 22:50, 10 February 2011 (UTC)[reply]

I read somewhere on the internet that the inner part of a chicken egg is coated with albumin (presumably the "white") and also I presume the outer membrane and shell before leaving the chicken, confirming that it is not just a giant cell. I assume that the egg in the ovaries is tiny, so an explanation is needed as to how that increases greatly in size to form a yolk. 92.29.123.158 (talk) 23:32, 10 February 2011 (UTC)[reply]

From reading the yolk article, my impression is that the yolk itself is not a cell, but rather a kind of food sac for a single cell in the middle of the yolk. Googlemeister (talk) 14:32, 11 February 2011 (UTC)[reply]

Yes, it really is a matter of choice of definition, but it seems inconsistent to regard an unfertilised egg as a single cell with an enormous storage vacuole, and a fertilised egg as a collection of dividing cells inside a food supply. I suppose it's just a matter of where one draws the boundary. Dbfirs 22:30, 12 February 2011 (UTC)[reply]

Human beings and ecosystems

I have three questions about the relation between human and its environment.I ask them all together because I think they are somehow related to each other.

1.what is the original ecosystem in which humans lived first? Do they even have an original ecosystem or they are jst formed in a way that they can fit in any environment?(or change the environment in a way that it would fit their needs)

2.why do human beings act differently toward their environment in comparison to other living things? What I mean is that other living things do not destroy their environment.they don't even change it a lot (in such ways that humans do).Why does human destroy its environment? Is it just a part of "nature"?

3.Is making homes, shelters,etc. seen in other apes? I don't mean "marking territories", Imean do other apes change thor environment to make it fit their needs?--Sina-chemo (talk) 18:35, 10 February 2011 (UTC)[reply]

In turn,

The African savanna, see the Out_of_Africa_theory.
Elephants and beavers modify their environment. It is generally believed that most animals don't really have a concept of 'the future' beyond what altruism gives.
Not really. Gorillas fold branches to make night-nests, and to make umbrellas but that is about it.

BTW, if you put '#' at the start of lines, they will be auto-numbered for you. CS Miller (talk) 18:45, 10 February 2011 (UTC)[reply]

"Out of Africa" doesn't require us to have evolved on the African savannah, because the places that are savannah now were not savannah then. We find early remains in what is now savannah, but we find coastal remains (like shellfish) with them. You won't find a modern, respected palaeoanthropologist saying humans evolved into their modern form on the savannah anymore, but there doesn't seem to be any great eagerness to embrace the alternatives either. Give it 10 years for the penny to drop... 86.164.25.178 (talk) 19:28, 10 February 2011 (UTC)[reply]

(edit conflict) For 1, see Olduvai Gorge. The original environment where modern humans evolved was likely the Serengeti savannahs of East africa. For 2, I'm not sure I follow the question. Humans don't really act differently; we are motivated by both self-preservation and species preservation just like all other living things. And other living things DO alter their own environments in profound ways. That's why evolution happens at all. Extinctions and climate shift happened before humans. Though I am pretty certain that anthropogenic changes to the environment are real, and are a problem, that doesn't mean other creatures have lived in an unchanging world before humans came along. Indeed, the environment changes all the time. The difference is that humans have ethics and morals and values which is different than many animals, and these ethics and morals (rightly in my opinion) make us care about other species. 3. Apes certainly change their environment to fit their needs. Many apes build nests and other shelters by tearing branches and leaves off of trees. --Jayron32 18:46, 10 February 2011 (UTC)[reply]

2. More examples if you're interested:Termites modify their environment to an incredible degree. The mounds serve to regulate temperature and humidity. Leaf-cutter_ants essentially practice agriculture, and heavily modify the environments in which they grow fungus. Ants have comparable biomass to humans, and they have moved as much earth as humans have (though they've had a little more time in which to do it).SemanticMantis (talk) 19:01, 10 February 2011 (UTC)[reply]

Sorta sidenote: many of our traits come from a previous (25 million years prior, as pre-ape monkeys) arboreal lifestyle, before bipedal walking marks where we usually start talking about human evolution. The most obvious example is our binocular and trichromatic vision - good sight is characteristically important in jumping through trees, etc. In our history since walking upright, hominids have gone through many environments, including vast forests spanning Africa, so our environmental heritage has not always been consistent, though I think(?) the consensus is that walking upright comes from evolving in the savanna.

The real juicy bit comes when one looks at the population bottleneck at the origin of homo sapiens (us), which reduced us to a population of as low as 1000 (see Toba catastrophe theory for one scenario). In such a situation, tiny adaptations matter immensely and can be somewhat of a crapshoot, which may explain how our intelligence ended up perhaps too high for the Earth's ecosystem to contain. And for a good-ol'-fashion scientific ~~rap battle~~ playa hating, check out the aquatic ape hypothesis. SamuelRiv (talk) 19:10, 10 February 2011 (UTC)[reply]

You may be interested in Holocene optimum, societal collapse and ecological niche. ~A H 1^(TCU) 22:22, 11 February 2011 (UTC)[reply]

Speed of sound faster than speed of light

Can one have a material such that the speed of sound is faster than the speed of light in that medium? How about where the phase velocity of sound is faster than the speed of light in vacuum? To these ends I was looking into the physics of metamaterials with negative bulk modulus, or to degenerate matter, but some guidance as to where to start would be nice. My handle of QFT should be adequate, but virtually none in matter waves. SamuelRiv (talk) 18:44, 10 February 2011 (UTC)[reply]

Possibly. See Slow light. --Jayron32 18:50, 10 February 2011 (UTC)[reply]

Before I started hanging out here, I asked something similar at that article's talk page, namely: What happens when the speed of light in a medium is precisely equal to the speed of sound in the same medium? Can the light be transformed to sound in some kind of "sonic boom"? Can the sound be transformed to light in some kind of sonoluminescence? Is there an equilibration of energy between the two transmission modes? I wonder if there's something to use in solid state refrigeration. See also [1] - pity I can't access it and don't know Mandelstam-Brillouin scattering or what an optical-acoustic soliton is... (but I never did get an answer there; maybe here we'll find out more - and yes, I forgot to access that when I had the chance) Wnt (talk) 19:12, 10 February 2011 (UTC)[reply]

In certain types of plasma, especially when subject to magnetic fields, there is often significant change in the speed of electromagnetic wave propagation. (I'm reluctant to call that the "speed of light", but the term may be applicable). There is also such a thing as conversion between acoustic- and electromagnetic waves. See magnetoacoustic wave. Magnetohydrodynamics is the study of the interaction between thermal, kinetic, and electromagnetic processes, especially in plasmas. Off the top of my head, I can't recall if the alfven wave is ever slower than the acoustic component. (In such cases, the electromagnetic and the acoustic wave are interacting strongly, exchanging energy). To determine for yourself whether the acoustic wave is faster than the electromagnetic wave, pick your favorite wave-speed metric (such as ω/k or ∂ω/∂k), and pick the parameters for your favorite plasma, and apply the velocity functional to each of the types of waves in plasmas. Nimur (talk) 19:27, 10 February 2011 (UTC)[reply]

This paper derives conditions under which the group velocity of photons matches the phase velocity of phonons in a certain type of plasma, but the details are way beyond me. Looie496 (talk) 19:41, 10 February 2011 (UTC)[reply]

Reverse sex change operation

Please tell me everything you know about reverse sex change operations. Egg Centric (talk) 20:04, 10 February 2011 (UTC)[reply]

Have you read our article? 109.128.101.244 (talk) 20:07, 10 February 2011 (UTC)[reply]

I see no article - that's kinda my point! Egg Centric (talk) 20:18, 10 February 2011 (UTC)[reply]

I'm afraid Wikipedia has an article on everything - it must be something wrong with your browser. Try turning your computer off and on again. Have you considered upgrading your RAM to support Wikipedia Platinum? SamuelRiv (talk) 20:34, 10 February 2011 (UTC) [reply]

There's no article about my penis, and that's massively substantial Egg Centric (talk) 20:47, 10 February 2011 (UTC)[reply]

Do you mean an operation to reverse a prior sex change operation? Such a procedure could certainly be done (and has been - the first result on my Google search was this article in the LA times, but it's far from a unique story), but it would be difficult to completely restore a person if they went all the way and had their genitals changed. --Tango (talk) 20:49, 10 February 2011 (UTC)[reply]

Yep. I'm loooking for any information - medicine, science, philosophy, anecdotes... all out of curiosity. Egg Centric (talk) 20:51, 10 February 2011 (UTC)[reply]

Are eyeballs always perfect spheres?

Are they? Why can't eyeballs be oval-shaped? or even cone-shaped? -- œ ^™ 21:10, 10 February 2011 (UTC)[reply]

Unfortunately they're not always perfect spheres. Astigmatism should give you some more information. --TammyMoet (talk) 21:24, 10 February 2011 (UTC)[reply]

No, they are not always even remotely spherical: check out salticid eyes. Many eyes change focus by changing the shape of the eye, which changes the optical properties. Salticids can't do this with their tube-eyes, so instead their retinas are stepped into various depths. They focus by sweeping the retina around rather than changing the optical properties of the eye. SemanticMantis (talk) 21:36, 10 February 2011 (UTC)[reply]

Evolution of the eye has some interesting material related to this, too. Comet Tuttle (talk) 21:38, 10 February 2011 (UTC)[reply]

I think it's safe to say, without even looking for a reference, that eyeballs are never perfect spheres.

My speculation as to why they tend to be approximate spheres is that, that way, they can easily be rotated to arbitrary angular positions (within a limited range, of course) and still fit in the socket. --Trovatore (talk) 21:55, 10 February 2011 (UTC)[reply]

Interesting! Thanks! (that salticid spider-eyes article was great). -- œ ^™ 22:56, 10 February 2011 (UTC)[reply]

Salticids in general are pretty cool. This paper [2] linked from the article is very accessible. It describes how

" Like a cat, and unlike any other spider, however, a salticid locates, tracks, stalks, chases down and leaps on active prey, with all phases of these predatory sequences being under optical control."

SemanticMantis (talk) 23:12, 10 February 2011 (UTC)[reply]

Is human saliva alkaline?

This 1918 New York Times newspaper has a dentrifice ad on page 24 which claims that a (sneer) German theory is wrong and that human saliva is naturally alkaline. Is this true? Our saliva article mentions the pH of a couple of components of saliva, but doesn't discuss saliva itself. Comet Tuttle (talk) 21:37, 10 February 2011 (UTC)[reply]

1918 toothpaste ads are not known for scientific accuracy. Anyone with access to litmus paper and a webcam want to spit for science? It should be a relatively easy question to answer... --Jayron32 23:00, 10 February 2011 (UTC)[reply]

There's a lot of dubious websites on the subject of saliva pH (see Quackwatch) but this page from Newcastle University in the UK suggests the pH varies from 6.3 (slightly acid) upwards to around 7.5 (slightly alkaline). The body is somewhat capable of maintaining pH in the mouth by releasing bicarbonate ions which neutralise acid produced by plaque. --Colapeninsula (talk) 12:22, 11 February 2011 (UTC)[reply]

No webcam, but I just tried the paper test and got a 7 on the pH. 10draftsdeep (talk) 16:09, 11 February 2011 (UTC)[reply]

You'd expect the optimal pH range for amylase to closely fit the average human saliva pH. ~A H 1^(TCU) 22:15, 11 February 2011 (UTC)[reply]

Roundness of the World

Why is the world round? Albacore (talk) 22:17, 10 February 2011 (UTC)[reply]

Our article section Planet#Mass mentions why all planets are spheres. Comet Tuttle (talk) 22:30, 10 February 2011 (UTC)[reply]

The article Hydrostatic equilibrium also contains some more info, depending on how technical the OP wants to get in answering the question. --Jayron32 22:57, 10 February 2011 (UTC)[reply]

And to be rather technical, the earth is not spherical, just loosely sphere-ish. See also geoid. SemanticMantis (talk) 23:18, 10 February 2011 (UTC)[reply]

The earth is closer to a perfect sphere then a billiards ball, and those are certainly not "loosely shere-ish". Googlemeister (talk) 14:26, 11 February 2011 (UTC)[reply]

A rocky planet tends to wobble - as a planet rotates, it tends to bulge out at the centre over time. Eventually, the bulge becomes unstable, causing parts of the mantle to regress back from the equator towards the pole. The decreased density under the overlying crust causes it to also collapse, leading to global volcanic activity. So over time, a rocky planet will have established an equilibrium equatorial and polar radii. Plasmic Physics (talk) 00:45, 11 February 2011 (UTC)[reply]

Although the Earth is only a rough approximation of an oblate spheroid, it is actually more round and more smooth (to scale) than a cue ball. ~A H 1^(TCU) 22:13, 11 February 2011 (UTC)[reply]

Amphetamine in Aspirin

Do aspirins (the pills that we buy at the drugstore, not the substance acetylsalicylic acid) contain amphetamine or other stimulating substance? Wikiweek (talk) 22:34, 10 February 2011 (UTC)[reply]

Well, Boots own-brand aspirin caplets contain nothing but aspirin and maize starch. I find it hard to believe anything sold as 'aspirin' would contain another active ingredient, in a country with regulations for medicines. It is possible that if you buy something sold as 'headache relief' containing aspirin, it might also contain caffeine, which would give some stimulation. For example, Anadin Extra contains aspirin, paracetamol and caffeine, as well as a variety of non-active ingredients. Personally, I wouldn't take those for a variety of reasons, but they could give you a bit of a caffeine buzz. 86.164.25.178 (talk) 22:40, 10 February 2011 (UTC)[reply]

Indeed, our caffeine article mentions that it is a common additive to aspirin formulations. DMacks (talk) 22:45, 10 February 2011 (UTC)[reply]

Much like the Anadin Extra linked above, Excedrin is a popular brand of aspirin+caffeine+acetaminophen in the US. SemanticMantis (talk) 22:59, 10 February 2011 (UTC)[reply]

Maybe this is pedantic, but I feel I ought to note for the OP that caffine is a xanthine-related molecule, and not an amphetamine. In the US amphetamine is a controlled substance. 65.29.47.55 (talk) 09:50, 11 February 2011 (UTC)[reply]

It should be noted, however, that methamphetamine is closely chemically related to several other drugs which are often sold in mult-drug formulations, such as pseudoephedrine. Perhaps that is what the OP is asking about... --Jayron32 22:55, 10 February 2011 (UTC)[reply]

I'm not sure where you're located, but in the USA every pharmacologically active ingredient in any kind of drug must be listed on the side in a specific area. So it's very easy to tell exactly what's in a given substance. It seems incredibly unlikely that there are any stimulants other than, in some pills, caffeine, but even the latter should be pretty carefully indicated. --Mr.98 (talk) 23:48, 10 February 2011 (UTC)[reply]

Instinct

Hi. Our cat just had a litter of eight kittens, and in case anyone cares yes they are adorable. I was wondering if there was a name for the instinct that a kitten has that tells it that it is able to trust its mother to take care of it and nurture it until it is old enough to survive on its own. Also how does this instinct work. --Thanks, Hadseys 23:17, 10 February 2011 (UTC)[reply]

I don't think the 'trust' part is instinct, I think it's a form of Imprinting_(psychology). The kittens may well latch on to the first thing that is warm and gives milk. rooting instinct describes how new-born mammals innately look for nipples. SemanticMantis (talk) 23:28, 10 February 2011 (UTC)[reply]

Is this assuming that "distrust" is the default? Isn't it more reasonable to assume that distrust is the one that would require an instinct or to be learned? Vespine (talk) 23:39, 10 February 2011 (UTC)[reply]

Well, one penalty for defaulting to trust any conspecific adult is infanticide_(zoology), which happens among lions, and probably occurs in farm cat populations as well. SemanticMantis (talk) 00:11, 11 February 2011 (UTC)[reply]

True instincts are a bit more complicated in most cases than the sort of thing you can just reason your way into and out of. I agree imprinting is probably the right article for this kind of behavior. I'm not sure that we can really talk about a trust or distrust instinct more generally. --Mr.98 (talk) 00:27, 11 February 2011 (UTC)[reply]

QUOTE: Well, one penalty for defaulting to trust. I wasn't suggesting there was a "default to trust", i was saying that maybe trust is THE LACK OF distrust. Just like an object doesn't "default" to cold in the absence of heat. What we "interpret" as trust in animals might just be a lack of observable "distrust". For example just because a infant animal doesn't run away from a snake, doesn't mean it has defaulted to TRUST a snake, it just hasn't developed a DISTRUST of snakes, whether instinctual or learned.. Isn't it true that truly wild animals in the savanna don't run away from humans because they haven't developed a distrust? Again I don't interpret this as "defaulting" to trust. Take it one step further, just because a child can't do maths, this does mean that lack of mathematical ability is the "default" mode, but it doesn't mean the child "defaults" to a lack of mathematical ability. Vespine (talk) 01:10, 11 February 2011 (UTC)[reply]

I just don't think this kind of reasoning enlightens us with regards to to actual animal behavior. You can't reason it out as if the animal was a little logic machine. They don't obey these kinds of rules; they aren't wired to all of the same kinds of concepts that humans find intuitive. (An example of a complex sort of instinctual behavior: Monkeys, by default, are not afraid of snakes. However if a monkey sees another monkey being afraid of a snake, the observing monkey will be afraid of snakes for the rest of its life. This logic applies to snakes and only snakes — you cannot get the same permanent results with respect to other animals. So monkeys are not instinctually afraid of snakes from birth, but they have the innate ability to be afraid of snakes if exposed to other monkeys who are afraid of snakes. There is a complex relationship here between instinctual and learned behavior.) --Mr.98 (talk) 02:43, 11 February 2011 (UTC)[reply]

Culture certainly plays a role in the lives of humans. If fear of snakes can be transmitted from one monkey to another, that would seem to me to be the rudiments of "culture" in nonhumans. Bus stop (talk) 14:55, 11 February 2011 (UTC)[reply]

I'm not sure if you are disagreeing with me, I wasn't claiming they were logic machines. My argument is a caution against attributing every single observation that can be made about an animal to an instinct, or a "trait" which was evolved for fitness. I've come across this on a number of occasions… I think the "cold" analogy isn't a bad one in this case; for example, there were people before the 19th century who theorized that "cold" was actually a property of matter, that there might even be an intangible fluid called frigoric which imbued matter with "cold", but the fact is cold is just a lack of heat, it's not a "property" in it self. Similarly I'm arguing that what we call "trust" in an infant animal might not actually be a "property" of animal behaviour at all, it does not need a "cause" or an instinct or a "learned behaviour", just like cold doesn't need a cause. Obviously there are "levels" of trust which CAN be learned, but simply not running away and not being scared of something sounds to me like what just happens until you learn "distrust", like the monkey/snake example you give. Vespine (talk) 03:54, 11 February 2011 (UTC)[reply]

I think I'm just one step backwards from agnostic about it than you are, is all. I'm not even sure "trust" is the right category at all for what is going on, is all I'm saying. Animal categories are complicated. If you tried to talk about whether monkeys innately "feared" snakes or not, for example, you'd go off on the wrong tack altogether, because it's really the more complicated situation that I've discussed above. Even getting the categories right is a tough thing with animals, because 1. they generalize categories differently than we do, and 2. brain circuits are often wired in ways that defy the way we usually "experience" them in our own lives. The combination of the two just means that making assumptions either way without evidence leads you into thickets of confusion. My thinking on this has been heavily influenced by Temple Grandin's Animals in Translation, which is a tremendously wonderful book for seeing how counterintuitive animal brains can be. --Mr.98 (talk) 04:00, 11 February 2011 (UTC)[reply]

Mother cats pay attention to newborn kittens—licking them. This may be an act that could play a role in signaling to the kitten the role that the mother cat will play for the next few weeks. This is just wp:original research. Bus stop (talk) 14:44, 11 February 2011 (UTC)[reply]

A newborn is blind and helpless. If it didn't trust its mother, what could it do to stop her? —Preceding unsigned comment added by 205.193.96.10 (talk) 20:52, 11 February 2011 (UTC)[reply]

Konrad Lorenz studied imprinting. Apparantly for ducks at least, the first thing they see moving is regarded as mother. 92.15.0.67 (talk) 21:37, 11 February 2011 (UTC)[reply]