Wikipedia:Reference desk/Archives/Science/2007 October 20

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October 20

Nerves

Why do some nerves in our body like in our fingers able to reattach or grow back together after they have been severed (not in all cases) while the nerves in our brain or around it are not able to?

The general rule is that axons (which make up the substance of nerves) do not regrow in the central nervous system (brain and spinal cord) while those of the peripheral nervous system (like those innervating the fingers) have at least some modest ability to do so. Specific reasons involve peripheral nerves' ability to maintain basement membrane integrity following nerve injury, the ability of peripheral glial cells to provide a substrate for axonal regrowth, and the secretion of axonal regrowth-inhibiting molecules by some gilal cells in the CNS. See nerve regeneration, which should answer some of your questions. --David Iberri (talk) 04:01, 20 October 2007 (UTC)

The search for molecular mechanisms continues. For example, see Nogo A. --JWSchmidt 04:13, 20 October 2007 (UTC)

How did they figure it out?

Seventy-one percent of Earth's surface is covered by water. How has this been calculated? - Pyro19 04:19, 20 October 2007 (UTC)

I suppose you're wondering how can we tell with all the untold and transient rivers, brooks, lakes, ponds and puddles and swamps in the world? Obviously, no truly precise figure even exists, it changes constantly and the boundary between dry land and water is quite fuzzy. But the Earth's surface area is about 500 million square kilometres (200 million square miles), so one per cent of that is about half the land area of the U.S. or Canada. If you just count the oceans and seas and major lakes plus a rough estimate for all the rest, you can be sure that your result will be accurate to plus/minus one per cent.--Rallette 08:38, 20 October 2007 (UTC)

A Monte Carlo estimate would actually be pretty straightforward. Just pick, say, 1000 random uniformly distributed (over the sphere, which is the only mathematically tricky part) co-ordinate points and check each point (easily done with modern technology such as Google Earth, but also possible simply by visiting the place in question) to see whether it happens to be covered in water. For a more accurate estimate, pick more points. —Ilmari Karonen (talk) 11:03, 20 October 2007 (UTC)

A disadvantage of using a Monte Carlo method is that it converges rather slowly. In order to get an answer that's twice as accurate, you have to use four times as many points. You can instead get linear convergence by using an equally-spaced grid of sample points on an equal-area map projection of the earth. With one of these maps, equal areas on the map correspond to equal surface areas on the earth, which is crucial to this calculation. Of the equal-area projections, the various Gall-Peters projections have an advantage in that you can have a rectangular grid of sample points that completely covers the planet, without any of the sample points being "off the map". As with the Monte Carlo method, you just count what percentage of the sample points are over water. MrRedact 20:22, 20 October 2007 (UTC)

Suger Free products

Are the ingrediants of suger free products safe for health ? —Preceding unsigned comment added by Aalokjani (talk • contribs) 06:42, 20 October 2007 (UTC)

You'll have to be a lot more specific than that, although we do have a section on health controversies involving specific sugar substitutes. Someguy1221 07:03, 20 October 2007 (UTC)

Depends on what they are and, more importantly, in what quantity. Sugar itself is one of the unhealthiest ingredients in a lot of food eaten in the West simply because there is too much in it. Avoid food that has sugar added to it. Or substitutes, for that matter, if that is what you're asking about. DirkvdM 09:46, 20 October 2007 (UTC)

• Some people believe sugar substitutes have their own dangers and you are forgetting that food without added sugar often has high amounts of fat. Anything can be bad for your health if you don't do it in moderation. If you use sugar moderately, there's no danger in using non-sugarfree products unless you are allergic. - Mgm|^(talk) 10:36, 20 October 2007 (UTC)

Too much Sorbitol can give you diarrhoea. Compulsive sugar-free Polo munchers beware. --Kurt Shaped Box 12:15, 20 October 2007 (UTC)

Don't listen to the widespread myths about added vs. "natural" sugar. Sugar is just sugar. Of course, there are different kinds of sugar, like sucrose (this one is most often meant when one just says "sugar"), glucose, fructose, galactose, mannose etc., but they cannot be separated into added vs. natural.

And you cannot be allergic to sugar.

Considering the original question, you should be more specific, but you may be interested in knowing how ADIs (acceptable daily intake) are established: Mammals (often rats) are fed a certain amount of the substance in question every day, for their whole life. Different doses are tried, and the animals are dissected. The dose (in amount of substance per kg body weight per day) at which no significant pathological differences are evident when compared to animals not fed with the substance is then divided by a safety factor (usually 100). Icek 16:45, 20 October 2007 (UTC)

Also, if you feed the hummingbirds - please don't give them sugar substitutes under the mistaken impression that it's 'healthier' for them. Yes, people really have done this. --Kurt Shaped Box 18:52, 20 October 2007 (UTC)

That's awful. If the hummingbirds can't tell the difference and it is their nearest 'food' source, they'll slowly starve to death. Actually, with the metabolism of hummingbirds, they might even die in a day or so. Reminds me of a vegetarian couple who had a dog (why?) and decided the poor animal should eat vegetarian too. I'm tempted to say people like that should not be allowed to have children. I don't mean that in an eugenetic sense, but rather that with all their good intentions they might end up torturing their own children. DirkvdM 17:25, 21 October 2007 (UTC)

Dogs are not obligate carnivores and can happily and healthily survive on a careful vegetarian diet. If they were feeding their cat a vegetarian diet, that would be a different matter. Honestly, it's like the Canary Islands all over again. What kind of trivia fiends are we, if regulars don't know these commonly-known 'little known facts' :) Next thing you know, they'll be claiming the tomato isn't a fruit... Skittle 22:47, 22 October 2007 (UTC)

There was a vegan kook I once encountered on a message board who was feeding tofu and meat substitute products to his OWL! The belligerent little fool didn't seem to see the correlation between the owl's diet and its constantly getting sick and would berate anyone who suggested that he put his politics aside and give it some real meat. He also tried to keep the bird in the same aviary as his finches at one point - with predictable (though not for him) and distressing-for-him results. --Kurt Shaped Box 23:35, 22 October 2007 (UTC)

At least the owl would have gotten some meat. --Psud 11:05, 23 October 2007 (UTC)

Surface tension of oil drop on water surface

I want to write an algorithm which models the behaviour of oil floating on a water surface. What are the forces etc. I need to take into consideration? Especially, what are the formulae for surface tension in this situation? Thanks. Jakob.scholbach 08:59, 20 October 2007 (UTC)

Fluid dynamics and Brownian motion might help you. − Twas Now ( talk • contribs • e-mail ) 09:22, 20 October 2007 (UTC)

Is it that you want a static model - ie giving the shape of the oil drop - in this case gravity Displacement (fluid) and for the surface tension the oil/water and oil/air surface energy - would be useful? Was it static or dynamic? —Preceding unsigned comment added by 87.102.17.46 (talk) 09:53, 20 October 2007 (UTC)

Well, I have in mind an algorithm/formula which solves the following: I have an oildrop on a (static) water surface, the boundary of the water container is somehow given. What form will the oildrop take eventually? For example, if it looks like two circles, which are "glued" along some intersection (thus somewhat resembling the 8), I want the algorithm to figure out that the form will separate into two smaller oildrops, as long as the container does not allow merging the 8-figure into one single (larger) drop. Thanks for the help. Jakob.scholbach 10:02, 20 October 2007 (UTC)

Right that's a static model.. It can be done... Have you tried working out the simpler case of when a drop of water is on a flat (could be glass) surface? and would you need more help to do this? If you can do that then the oil on water case should be a possibiity.87.102.17.46 10:22, 20 October 2007 (UTC) sorry misread

Actually there's not much reason for it to break into two drops at all - for it to do that would require some one stirring it, or a lot of currents in the water. If the water is perfectly still then the oil drop would spread out to a circular thin sheet. That's what would (almost certainly happen)

But you ask for the opposite it seems - for a drop to separate into two smaller drops... If this occurs then will those drops separate into 4 even more small drops? If so you may end up with a monolayer

Can you re-explain - the description is a bit confusing.87.102.17.46 10:28, 20 October 2007 (UTC)

I didn't know that a glass surface is easier. If you could provide help on this, this would probably be sufficient for my purposes. (Eventually, I want to apply it to an image recognition process, so it does not exactly matter to use the most rigourous approach, as long as it still works). Thanks again Jakob.scholbach 10:29, 20 October 2007 (UTC)

I'm talking about something like . The black gadget is the oil-drop. The red lines are the boundary of the container. Thus (I suppose) the drop could not attain its optimal (spherical) form, but should separate into two smaller drops. These could (and would) take spherical form and would not split into smaller drops. Jakob.scholbach 10:37, 20 October 2007 (UTC)

Right - that's complicated.. First of all I can assume that the oil is repulsed by the sides of the container - (otherwise it will just stick to the sides - with hemispherical ends I imagine).

With reference to the glass I was thinking at first you meant the cross sectional shape eg

The main factor here is that the edge of the drop (the perimeter) is at higher energy than the innards - this is why drops of water are spherical/circular - to minimise the perimeter length/surface area.

So for your drop to split into two you would have to show that the two drops have a lesser perimeter than the whole drop.. Actually I don't think this is the case.. I think it's probably the other way round ie two small drops would fuse together.

Anyway I could help with the cross section problem - but I don't think I can solve this one. Hopefully someone else will.. If you get no luck I would try the maths desk - someone there would (hopefully) have sufficient skill to be able to solve this.

Just to clarify though - do you want a 'formula' that gives the shape of the drop as a function of time? (it might be possible to 'bodge' this..)87.102.17.46 11:00, 20 October 2007 (UTC)

OK. I don't need an exact formula, which tells the evolution of the drop(s) depending on the time etc. I just want to find a model which (in a computer image recognition situation) tells me to separate the above two parts into two separate ones. I thought the drop model is the right one. But I don't have to stick to this. Just something which quantifiably tells me: the point, where the two parts "kiss" is not optimal, in the sense that a drop would "try" to change its shape there in order to minimize its boundary length locally at this point/area. Jakob.scholbach 11:31, 20 October 2007 (UTC)

In terms of the image recognition - would searching for circles work - in the case where the figure 8 situation occurs it should recognise two circles - assuming you look for circles using a boundary condition and set the program to register a circle when ~70% or more of the circle boundary is present?87.102.17.46 11:51, 20 October 2007 (UTC)

Regarding your sample image, instead of splitting in two, wouldn't the smaller portion of oil (on the left) actually get pulled into the larger portion (on the right)? It's rather like having two identical balloons with different amounts of air in them connected. The fuller balloon will take most of the air from the less full balloon because the tension on the outside of the less full balloon is higher than it is on the fuller balloon. (see here) -- HiEv 17:27, 22 October 2007 (UTC)

Hm. That may work. I didn't think in this direction, though, as the forms may also be rather elliptic or oval. Jakob.scholbach 12:08, 20 October 2007 (UTC)

Distance to the moon and sun calculation

Indian proto physicist/mathematicians calculated the distance from earth to the moon and sun early in human history (was it 2 millenia ago?). What method did they use? Keria 09:34, 20 October 2007 (UTC)

I can't find a reference for that - though I looks likely that they knew that the sun diameter/earth-sun distance ration was 1/108 - this can be obtained by angular measurements.

The article Indian astronomy doesn't mention it - is there a reference for this?87.102.17.46 09:50, 20 October 2007 (UTC)

See Parallax#Lunar parallax and Parallax#Solar parallax.--Shantavira|^{feed me} 12:03, 20 October 2007 (UTC)

A Greek astronomer did such a calculation "2 millennia ago": see Aristarchus of Samos and Aristarchus On the Sizes and Distances. I don't say that it wasn't done in India also; ancient Greek learning is more remembered in western countries. --Anon, 13:48 UTC, October 22, 2007.

DVD-R Strange optical effect

When looking at a white light (bulb) reflected through a dvd-r I get a strange optical effect.

1. A primary reflection (slightly coloured due to the funny colour of the disc)

2. Some bands of colour that I'd expect due to diffraction.

3. 3 sub images of the light source (quite in focus like the primary reflection) except that they are coloured blue, green/yellow and red. (these are obtained by titling the disk so that the primary (whiteish) image is not visible)

What can be the cause for (3.) - the images are a. in focus b. clearly three different colours and c. not smeared like I would expect for diffraction.87.102.17.46 11:26, 20 October 2007 (UTC)

What do you mean by "relfected through"? Exactly what kind of DVD-R are you using? How close is the DVD-R to the bulb? --JWSchmidt 15:50, 20 October 2007 (UTC)

"Reflected by" I should have said. (I'm not looking through the disk). (ie my eyes are on the same side of the disk as the light)

Make = MAXELL (if there's more info tell me what to look for..)

The DVD-R is 4-10 ft from the bulb.

Another point the 'reflected' monochrome images are smaller (less than 1/2) the main reflected image.

The red image is quite blurred

The blue and green/yellow are quite clear though - I can see in the 'reflection' features on the light..Because the lampshade is round - I can see 3 different coloured lampshades - clearly as 3 round objects (the images overlap)87.102.17.46 16:27, 20 October 2007 (UTC)

(And I'm looking at the recording layer obviously not the top surface with 'maxell' etc printed on it)87.102.17.46 16:31, 20 October 2007 (UTC)

Note It looks like the bands of colour in 2. were from an external light source.87.102.17.46 19:05, 20 October 2007 (UTC)

• I only see one reflected image using two other brands of DVDR and an incandescent light bulb. --JWSchmidt 02:10, 21 October 2007 (UTC)

Commercial DVDs are often multi-layer. You might be seeing a reflection off the two layers, and the face of the disc. You might not see it on a DVDR, since many of them are single-layer (4GB) --Mdwyer 05:56, 21 October 2007 (UTC)

Would the diffraction from a monochromatic light source form an image (the light is fluorescent)87.102.16.28 08:20, 21 October 2007 (UTC)

Fluorescent lamps don't actually put out "white" light. They have strong peaks at the particular colo[u]rs emitted by Mercury (element) and a redish component emitted by the phosphor. You're seeing a separate image for each wavelength that's prominent in the light; the ones that are "smeary" are because there, the spectrum of the light is more-continuous, without strong individual "peaks" (colo[u]rs).

Atlant 17:14, 21 October 2007 (UTC)

Thanks I finally worked that one out.. There's a related question about diffraction below if you can help.87.102.0.6 13:38, 22 October 2007 (UTC)

Physics-solid state

What is "spin injection"?How could it be done?Is a superconductor material used for it? —Preceding unsigned comment added by 80.66.179.40 (talk) 12:58, 20 October 2007 (UTC)

It's the generation of polarized electrons - see spin pumping and spintronics. Icek 17:11, 20 October 2007 (UTC)

...Of course, if someone wants to write an article on spin injection, we'd all be pleased to see the redlink turn blue. TenOfAllTrades(talk) 17:37, 20 October 2007 (UTC)

I think a superconductor is not used - or at least is not neccessary for this process.87.102.17.46 17:45, 20 October 2007 (UTC)

Placed in the cold

say a person is placed in an environment where he constantly feels cold. given that he consumes the same amount of food (or rather the same energy intake) would he get fatter or thinner? would he get fatter because his body would respond to the cold by becoming a better fat storer and build up layers of fat and that his body slows down metabolism to conserve energy; or would he get thinner because his body would try to generate heat to keep warm?--82.46.27.191 14:23, 20 October 2007 (UTC)

Presuming that the person's weight and food intake were perfectly balanced before being put out in the cold, he would get thinner. Shivering uses energy, if food (energy) intake remains the same, he'd get skinnier until he reached the weight that his energy intake/expenditure could support. --Psud 15:11, 20 October 2007 (UTC)

This article is about rats, but it describes results for humans: "data are available to suggest that early exposure to cooler environmental temperatures may increase body weight in humans as well". --JWSchmidt 15:42, 20 October 2007 (UTC)

That article is describing an experiment where the rats were raised in various temperatures, and had access to as much food as they needed. The original question states "same energy intake". The article also describes the effect of rearing temperature, not the effect of putting an adult animal which grew up in "normal" temperatures into a cold environment. --Psud 23:19, 20 October 2007 (UTC)

If energy expenditure would in the long run cause the torso to hypothermiate (that's probably not a verb :) ) then it would make sense to keep that warm at the expense of the (relatively expendable) limbs, possibly even by storing fat (no idea). But the body would not know that, at least at first. And that this makes sense (to me) doesn't mean that's what the body would do. Of course it's also a matter of how active you are, but I suppose you mean sitting still. In such a case the body starts to shiver at first (an observable fact), which keeps the whole body warm. But you're talking about a much longer period of time, so maybe after a while the body will 'get the message' that this is permanent and change its strategy. Then again, if you're talking about such a long time, then the cold can't be too severe, or you'd die before any weight-effects can be observed. This reminds me of the partizans in Belarussia who started as escapees from nazi prisons and had to endure up to months in the cold before they found a partizan camp (those forests are huge and of course the partizans were trying not to be found). So maybe that would be a good source - a real-life experiment. DirkvdM 07:17, 21 October 2007 (UTC)

use of fins(extended surfaces)

why is the use of fins sometimes avoided? —Preceding unsigned comment added by 59.95.220.51 (talk) 18:11, 20 October 2007 (UTC)

It's not entirely clear what subject is being asked about - could you be more specific as to what sort of fins?87.102.17.46 19:06, 20 October 2007 (UTC)

To reduce drag perhaps. Or because they can catch in your throat. Unless you are able to give us some context, perhaps it would help to read the article on fin which tells you under what circumstances fins might be employed.--Shantavira|^{feed me} 09:18, 21 October 2007 (UTC)

Can transfusion cure diseases?

If we do multiple transfusion in the case of AIDS or malaria, why does it not cure a patient? Some part of the virus/parasites are getting out of the blood, aren't they? —Preceding unsigned comment added by 83.59.233.33 (talk) 18:18, 20 October 2007 (UTC)

• I'm not sure about malaria, but I do know that the HIV virus incorporates its viral DNA into a cell's nucleus, so even if the blood is transfused, said DNA could just be activated to make more viral particles. Also, not all infections go through the blood stream. Sometimes a virus can simply invade a neighbouring cell through a near-direct interaction. You really gave the answer yourself. Some of the virus will be in the blood, but not all of it, so targetting the blood alone won't cure the patient. - Mgm|^(talk) 18:26, 20 October 2007 (UTC)

• In the case of AIDS, it is commonly accepted that the HIV virus is responsible for the disease. In a blood transfusion, you (optionally) remove some of the blood from the patient and replace it with blood from a donor. Soon after this new blood is given to the patient, it, too, would become infected with the HIV virus. You would have to drain all of the blood out of a patient, "rinse" the blood vessels, and then refill the patient with new blood. As far as I know, such a process is not possible in modern medicine. The other problem you would encounter is that transfused blood from a donor has white blood cells removed, so the patient would be very susceptible to disease. Andrewjuren(talk) 18:36, 20 October 2007 (UTC)

OK, some virus will be in the Bone Marrow, but it can also be chemically destroyed. So, how does the virus can still be there? —Preceding unsigned comment added by 83.59.233.33 (talk) 18:43, 20 October 2007 (UTC)

I asked a similar question a while back myself WRT to HIV/AIDS. I got some good, detailed answers. Have a read. --Kurt Shaped Box 18:47, 20 October 2007 (UTC)

I recently read that with current drugs, HIV can be killed in all parts of a person's body, except in the brain (where it is safe behind the blood-brain barrier) and the testicles (where presumably a similar barrier exists). --Psud 23:16, 20 October 2007 (UTC)

But without either one, you probably wouldn´t wanna live anymore would you? :p --antilived^{T | C | G} 06:10, 21 October 2007 (UTC)

Replacing some of the blood would be like bloodletting, which doesn't help against infections. But suppose we would try to replace all the blood. I doubt if that can be done. Blood transfusion is meant to replenish the blood of someone with severe blood loss. One might also use it to reduce the concentration of some substance in the blood (don't know). But a virus would have to be completely wiped out, so all the blood needs to be replaced. And unless you do the transfusion at a coronary artery, where all the blood passes through, you'll always miss some of the blood. But let's be optimistic and suppose one complete transfusion (about 5 l of blood) would replace 90% of the blood. With the second transfusion you'd have replaced 99% (not mathematically entirely correct, but this is just an indication). To reduce the remaining blood to one drop (say 5 mm³) you'd have to replace 1/100³ = 99.99999% of the blood. That would require 7 complete transfusions (how many donors would that require? About 100?). But that one drop would still hold enough viruses to get you sick again. I don't know any of the details here, just wanted to point out this issue. DirkvdM 07:59, 21 October 2007 (UTC)

The easy answer: HIV isn't just in the blood, it's other places too, and so a complete blood exchange would not result in a cure for AIDS. Psud alludes to these "reservoir sites" in his answer. Similar answers apply to most forms of malaria as well, where parasites in the liver would not be removed by blood transfusion. Also: the coronary arteries are small, and only a tiny amount of blood passes through them at any one time. They are terminal arteries, not major arteries. - Nunh-huh 09:00, 21 October 2007 (UTC)

On second thought, if there is some stage in the parasite's life cycle where it needs to get into the blood, it might still work. Isn't that the case with malaria, the cause of the fever resurging every two or three days because the parasites break out of the cells and go into the bloodstream to infect new cells? Suppose you could continuously refresh the blood with some affordable substitute, then wouldn't that eventually reduce the number of parasites to something the body can deal with? At least it would reduce the severity, which could be a life saver. Of course the substitute would have to be really cheap if it is to be used in such high quantities for (usually) the poorest people on Earth. DirkvdM 17:34, 21 October 2007 (UTC)

As cheap as quinine, you mean? - Nunh-huh 00:41, 22 October 2007 (UTC)

Probably not, but the problem is that anti-malaria drugs are becoming ever less effective and new ones don't come fast enough. And that includes quinine, I believe, but I can't find the word 'resistance' in the article. DirkvdM 07:15, 22 October 2007 (UTC)

Old school antibody production (for research applications)

Since antibodies used in research can be so expensive, do some scientists still prepare them the old fashioned way, raising an immune response in an animal? If you happened to do a lot of research with a few different proteins, it would surely be economical to end up with a hybridoma, producing your favourite antibodies? Is the amount charged reasonable, or are they rolling in profit? --Seans Potato Business 19:29, 20 October 2007 (UTC)

Making antibodies for research use is not cheap, but if you will be using large amounts of a particular antibody it might be worth making your own. Sometimes there is a well-defined antigen that efficiently stimulates antibody production in rabbits. Immunizing a few rabbits with such an antigen can provide you with antiserum that might cost you many thousands of dollars to buy commercially. Making your own rabbit antisera is easy to do if your institution routinely houses rabbits. Hybridoma production requires some special skills and equipment. If you have access to cell culture facilities and your institution houses mice, then it might be worth trying to produce a monoclonal antibody. Growing and screening hybridoma cell lines can be labor-intensive. However, many hybridomas have been made by research scientists, and if you ask around it is often possible to find someone who will send you the hybridomas you want. Then you just need to culture them and collect the culture medium. Of course, anytime you make your own antibodies, you have to take the time to characterize them. If you just need a small amount of an antibody, it is best to just pay a commercial source. --JWSchmidt 20:37, 20 October 2007 (UTC)

Imperfections in gel electrophoresis

What causes those imperfections, where bands appear to diverge in the same way a person's handwriting might leave the lines on which they're writing, if they look up from the page and continue to write? Sometimes, you see an individual line which is kind of squiggly. My guess would be uneven application of electric current and/or, maybe more likely, uneven density of the gel due incomplete mixing and/or different rates of cooling. Are the likely and/or are there any other contributing factors? --Seans Potato Business 19:50, 20 October 2007 (UTC)

It sounds like you are describing several different problems. Sometimes the gel is not polymerized in a uniform way. One way this can happen is if you forget to mix the gel's solution before trying to form the gel. Another common problem is loading unequal samples on the gel. This can either be different volumes loaded into wells or use of different buffers for some of the loaded samples. For individual lanes, irregularities can be generated by having samples containing high molecular weight substances or undissolved solids that do not migrate normally through the matrix of the gel. Sometimes a dirty or damaged glass plate is to blame. --JWSchmidt 20:17, 20 October 2007 (UTC)

This page (and the links on it) show a whole bunch of real-life gels that have suffered various indignities. Do any of them look familiar? TenOfAllTrades(talk) 04:39, 21 October 2007 (UTC)

opu

thank you

what is theveterinary

hofast make veterinary  —Preceding unsigned comment added by 209.2.60.95 (talk) 19:55, 20 October 2007 (UTC) 

We have articles Veterinarian and Veterinary surgeon

To become a "vet" as it is commonly known takes 5 to 6 years at degree level. Prior to that school or college course need to be taken and examinations passed. So quite a long time.87.102.17.46 20:04, 20 October 2007 (UTC)

(edit conflict) When you say "the veterinary", I assume you mean the noun meaning "animal doctor". Normal American English uses "veterinarian" for the noun, but "veterinary" can also be used that way, especially in England, or parts of it, I believe. In fact, the words "veterinarian" and "veterinary" are synonymous both as nouns and adjectives. And, yeah, we help people, but it takes a minute or two. Jeeze. --Milkbreath 20:06, 20 October 2007 (UTC)

Yes that's right - it can take a while to get a good answer - sometimes only minutes, but more often hours or even days. The questions stay on this page for up to a week and then get archived. It's very rare for a question to go unanswered.87.102.17.46 20:33, 20 October 2007 (UTC)

shokna

you dont halp any bardy . —Preceding unsigned comment added by 209.2.60.95 (talk • contribs)

Perhaps you are looking for this...Homework Help. Clem 20:50, 20 October 2007 (UTC)

Crystals Being Grown in Space

I have come up with a perplexing issue. I have heard that there was a project in which they put frozen crystal compounds into tubes and launched them in space to see how they would grow. Was there ever a project like this and if so when? What data did they collect? 71.142.239.228 22:42, 20 October 2007 (UTC)Macky

Are you referring to protein crystallization experiments? [1] Rockpocket 01:31, 21 October 2007 (UTC)

I believe I am. Thank you for responding.(UTC)Macky —Preceding unsigned comment added by 71.142.239.228 (talk)