Wikipedia:Reference desk/Archives/Science/2006 August 3

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Human-raised birds[edit]

Say if I was to hatch a bird (e.g. a crow) from the egg myself and raise him from chick to adulthood without him ever seeing another bird, would he still be able to fly? Or would he not know how and walk around like a human instead?

It would depend largely on if it fledged properly. Actually, the article uses the term a little differently from how I use it; I use fledge to mean "to learn to fly as a chick at the right developmental stage." In wild birds this seems to happen when the flight feathers are significantly (but not necessarily completely) grown out, which incidentally is right now in the temperate northern hemisphere, and it's a time of high mortality for chicks. With many pet birds such as parrots, if they don't learn to fly at the right time during their "chickhood," often they never really do. I had a yellow-collared macaw who never fledged and who absolutely refused to fly voluntarily, even though I let his flight feathers grow out and tried to teach him with gentle tosses to the bed. I also have a ringneck parakeet who didn't fledge as a chick either, but he has done better at learning as an adult. Neither of these birds was raised by other birds; what matters with a human-raised bird is whether it is taught to fly. --Ginkgo100 talk · contribs · e@ 03:35, 3 August 2006 (UTC)[reply]

It's really hot in here...[edit]

and the airconditioner isn't working. how hot does it have to be before a computer goes from sluggish to not working at all? it's already over 100 (oF) in here, how much more can it take?--152.163.100.74 01:48, 3 August 2006 (UTC)[reply]

It depends on how efficient your computer's cooling system is. Generally consumer CPUs are rated at anything between 65° and 95°, so the ambient temperature isn't going to cause problems per se, but it will obviously make cooling less efficient. You can monitor the internal temperature sensors with free tools e.g. Gnome Sensors Applet. EdC 03:04, 3 August 2006 (UTC)[reply]
Removing the computer cover and pointing a fan at it can help dramatically, if it tends to overheat. StuRat 05:45, 3 August 2006 (UTC)[reply]

Using munitions to disrupt hurricanes[edit]

Hello all - I have a general question about using munitions to disrupt hurricanes. Is something like this possible? I read over the hurricane page (specifically the section on Artificial dissipation) and Googled this topic, but I really did not find anything that really answered the question.

Here is the scenario: If a Rita/Katrina-type hurricane should brew in the Atlantic Ocean, is it possible to drop several powerful cluster bombs throughout the eye (and exterior) of the hurricane and disrupt or eliminate the hurricane, or at the very least lessen the force of the hurricane. I would imagine that thousands of explosions within the center of the hurricane, at the waters surface, and beneath the waters surface would severely disrupt the strength of the hurricane. I think this might be akin to using explosion to put out fires: the vacuum created by the explosion might disrupt the wall and eye of the hurricane, thus decreasing the force of the hurricane.

thanks,

-Rangermike 03:43, 3 August 2006 (UTC)[reply]

Simply put, there's no way that would work. Here is a good article explaining why. Titoxd(?!?) 03:46, 3 August 2006 (UTC)[reply]
Thanks for the comment. I just would imagine that if there were thousands of powerful cluster bombs being detonated at all altitude levels, at the waters surface, and under water, this would have the potential to disrupt the hurricane. -Rangermike 03:52, 3 August 2006 (UTC)[reply]
As a side note, I would not advocate using nukes to disrupt the hurricane; conventional munitions only. -Rangermike 03:56, 3 August 2006 (UTC)[reply]
There's just not enough bombs to actually do anything to the hurricane, and tropical cyclogenesis is not something we can completely predict yet (as a look at 2006 Atlantic hurricane season's talk page archives show). Titoxd(?!?) 03:56, 3 August 2006 (UTC)[reply]
Thanks for the info! -Rangermike 04:05, 3 August 2006 (UTC)[reply]

I would think many nuclear weapons would be needed to disrupt a hurricane. A new hurricane would spawn almost immediately, in the same area, however, as the water temp cooling would stop once the old hurricane was disrupted. This hot water would then generate a new hurricane in the same area. Another method of disrupting hurricanes would be to dump millions of tons of a special gel (which absorbs a million times it's weight in water) from cargo planes, into the hurricane. This particular gel (I can't recall the name) dissolves in sea water, and is nontoxic. Unfortunately, the hurricane would also respawn after this method was used. The real cure for hurricanes, then, is to prevent to water from overheating in the first place. I propose partially covering the tropical oceans with solar collectors to generate electricity and prevent a heat buildup. Perhaps in a century of two we can manage it. StuRat 05:41, 3 August 2006 (UTC)[reply]

Well, that has not been tried experimentally, but the Dyn-O-Gel experiment you mentioned has been tested in numerical models and it doesn't work well either. And no, icebergs don't work either. Mostly, it is a problem of scale; we don't have enough resources to actually do anything to something the size of a hurricane. Titoxd(?!?) 06:39, 3 August 2006 (UTC)[reply]
You're somewhat correct that a tropical cyclone would probably remain in the same place, but I doubt it'd be a new hurricane because of high SSTs. Hurricanes don't just "spawn" in hot water, else New Orleans would be hit every other month when the Loop Current sheds an eddy. The larger-scale structure takes too long to develop and they're fairly fragile while developing. If you could really just get rid of the hurricane entirely or put it back to its "random mess of convection" stage, it would take a long time for it to return to its prior strength.
But using bombs (i.e. randomly blowing up the hurricane's structure) would probably only degenerate it back to a tropical storm's structure at most if you're lucky and get the right bits. Tropical storms already aren't that organized and you probably won't find any structures to bomb on a small-enough size scale. Also, bombs probably wouldn't be able to stop the winds and low-level convergence and upper-level divergence already spun up. The same things that were favorable to the intensity of the 'cane before would probably act to re-strengthen the same storm. —AySz88\^-^ 06:58, 3 August 2006 (UTC)[reply]

Given that hurricanes are a phenomena that is hundreds of km wide, I doubt very much that any munition could have any significant effect, but seeding the clouds to make rains at appropriate location(s) and time(s) could shift the path of an hurricane enough to avoid populated areas.

Sounds like Project Stormfury. Titoxd(?!?) 05:00, 4 August 2006 (UTC)[reply]

HereThat website brings up an interesting question. Is it possible to harness a large portion of that energy? Deltacom1515 00:25, 4 August 2006 (UTC)[reply]

Gasoline[edit]

Does gasoline go bad or lose octane overtime?

Not if it's stored in an airtight container. If it's left out in the open, though, it will quickly evaporate, forming dangerously flammable vapor. —Keenan Pepper 04:03, 3 August 2006 (UTC)[reply]
In the UK, what is sold as "unleaded petrol" does indeed "go off". Opinions differ on how long that takes. Notinasnaid 10:56, 3 August 2006 (UTC)[reply]

Scientific question[edit]

How fast can a three legged cheetah run?

Thirty-five miles an hour [1] Rockpocket 04:24, 3 August 2006 (UTC)[reply]
Aaaawwwwww!!!! Rockpocket, you ROCK! Rock by name, rock by nature.--Anchoress 05:45, 3 August 2006 (UTC)[reply]
He is an island. Pocket-edition. DirkvdM 13:40, 3 August 2006 (UTC)[reply]
*blush* Rockpocket 18:14, 3 August 2006 (UTC)[reply]
Given that the average 4-legged cheetah can run at up to 70 miles an hour, the average three-legged one would logically be able to run at 52.5 mph.
Then again, if it's on nandrolone or some Testosterone-based performance-enhancing drug, who knows how fast it can go if it's "cheeting". --Dweller 14:16, 4 August 2006 (UTC)[reply]
I had a zoology professor who claimed a no-legged cheetah could run six miles per hour. --Ginkgo100 talk · contribs · e@ 20:14, 3 August 2006 (UTC)[reply]
Sorry I left that all without context ... my professor's point was that the mechanics of the cheetah's spine contributes something like 10% to its speed.
It would then move a bit like a caterpillar. I'd love to see that! DirkvdM 18:54, 4 August 2006 (UTC)[reply]
Step away from the cheetah, Dirk. Skittle 19:43, 4 August 2006 (UTC)[reply]

List of countries by electricity consumption - part 2[edit]

In the List of countries by electricity consumption someone seems to have gone through the trouble of filling in the per capita values for scandinavian countries, where these values are very high. Same for Canada (even higher than the US). For other western countries (excluding the US) it's much lower. I can understand a higher energy consumption due to heating, but why do they consume two to four (!) times as much electricity? DirkvdM 13:37, 3 August 2006 (UTC)[reply]

I looked at that and I thought that it isn't accurate to claim that each person is consuming 2-4 times the electricity. The figure is dividing the country-wide consumption by the population. So, a completely robotic factory with only a handful of workers will consume a lot of electricity. That is being added to each person's average usage on that specific table. Therefore, I expect industrialized nations to have a much higher per-capita usage due to business/factory/government use and not really due to personal use. --Kainaw (talk) 13:47, 3 August 2006 (UTC)[reply]
Norway, for instance, produces a lot of cheap hydroelectric power, and has the lowest population density in Europe. Despite having no bauxite, they are one of the leading producers of aluminium.EricR 14:13, 3 August 2006 (UTC)[reply]
The situation in Canada is similar. There are a number of sites that produce a lot of hydroelectricity, and Canada imports enough bauxite to refine nearly 3 million tons [2] of aluminum each year; at 15 kWh per kilogram of aluminum produced, that comes about 40 GWh of electricity consumption per year. In other words, a single resource industry accounts for about 8% of Canada's total electricity consumption. Most of that aluminum is exported to other countries – Canada is the second-largest aluminum exporter in the world, after Russia[3] so counting that electricity use as 'Canadian' gives a somewhat skewed picture of that country's consumption. TenOfAllTrades(talk) 14:33, 3 August 2006 (UTC)[reply]
I guess industry could account for some of it - I also assumed it's because it's so cold all the time that heating costs were higher. But I don't know. --198.125.178.207 17:39, 3 August 2006 (UTC)[reply]
There ought to be a correlation between per capita wealth and consumption. For energy, think of heating houses, cooling houses ; and this, mostly in countries located where temperatures vary : wealth is related to temp variation (personal research). --DLL 18:32, 3 August 2006 (UTC)[reply]
Like I said, I assume heating is not done with electricity, so that couldn't cover it then. And bauxite represents 'only' 8% of the electricity consumption of Canada, but the total consumption is more than double that of other western countries, so that can't explain it. And for Norway and Iceland it's even three resp four times as high. Those are huge differences. But Norway does have a lot of water power, so maybe they use more electricity and less fossil fuels. Hold on, don't they have a lot of cars running on electricity? That might explain it. And then Iceland. That has a lot of geoithermal power. But I can't think of how that could explain it. Is it just a coincidence that countries close to the North Pole use more elctricity? DirkvdM 19:24, 3 August 2006 (UTC)[reply]
Aaaaw c'mon, let's just come out and say it! Canadians are the energy hogs of the entire world! :-) Oh sorry, can't talk any more, I have to take my recycling out of the dishwasher, and the dryer's finished heating up the bathroom for my shower. ;-)--Anchoress 19:32, 3 August 2006 (UTC)[reply]
Stop that - don't you know it isn't legal to criticize countries other than the US? --Bmk 19:44, 3 August 2006 (UTC)[reply]
Oops, sorry. Well what if I said it's the US's fault that we're such energy hogs?
From a soon-to-be-aired episode of Oprah
[Canada] (sobbing) He doesn't respect me! He never listens to me! I wouldn't have a problem with reckless consumption if I got the acknowledgement I deserve! I mean, how big do I have to be before I get some recognition?
[Oprah] There there, little Canada. When he runs out of steam I'm sure he'll notice you.
--Anchoress 19:55, 3 August 2006 (UTC)[reply]

Bubbles[edit]

Why do soap bubbles burst ?

They don't have to. If gravity didn't pull down on it, making the bottom thick and heavy while the top becomes thin and fragile, it would just go on being a happy little bubble. But, gravity is evil and hates soap bubbles, so it pushes down and down and eventually the top is so thin that the surface tension cannot hold. The little soap molecules cry as their fingers slip and pop - no more soap bubble. --Kainaw (talk) 14:02, 3 August 2006 (UTC)[reply]
I disagree. Even without gravity the bubble solution would quickly evaporate and burst the bubble. Perhaps in a zero g, 100% humidity environment they might last until they hit something. StuRat 20:44, 3 August 2006 (UTC)[reply]
My answer was limited in scope to Earth-bound bubbles. Gravity gets to them faster than the environment. I learned about it in a strange place - watching a documentary on making colored bubbles. Turns out that making bubbles with a solid color is very hard. Gravity pushes the dye to the bottom and then POP, you get a stain on the floor. --Kainaw (talk) 13:34, 4 August 2006 (UTC)[reply]
The solution: bubbles in space. --130.161.182.77 14:12, 3 August 2006 (UTC)[reply]
..with the pressure equalized inside and out? Can a bubble even exist in space?--Shantavira 14:47, 3 August 2006 (UTC)[reply]
"Soap bubbles in space" - interesting question. Of course the Earth itself is in space and it is possible to make soap bubbles here. In zero gravity (or microgravity really) we find soap bubbles on the International Space Station here. For bubbles in vacuum: possible, but the liquid will evaporate quickly and thus the bubble has only a short lifetime[4]. Weregerbil 15:06, 3 August 2006 (UTC)[reply]
In Yakov Perelman's Physics for entertainment, he mentions that the bubbles made of right solution are not as short lived as we presume them to be. He cites examples where bubbles were stored for (I think) about a month --Wikicheng 04:48, 4 August 2006 (UTC)[reply]
What about dust, too? I bet that may have something to do with it, along with surface tension. --71.98.25.103 03:13, 9 August 2006 (UTC)[reply]

Bike Brakes At The Hub[edit]

My bike has brakes that occur at the hub of the wheel, instead of at the top (pressing against the wheel rim) like I'm used to. What kind of brakes are these? --130.161.182.77 14:01, 3 August 2006 (UTC)[reply]

See bicycle brake systems and you should find the brakes you have. --Kainaw (talk) 14:14, 3 August 2006 (UTC)[reply]
Sounds like drum brakes. A type of drum brakes for bikes is called coaster brakes. StuRat 20:37, 3 August 2006 (UTC)[reply]

Other non-omnipresent animals like hedgehog[edit]

Hello,

last week I experienced the not so frequent pleasure of finding a hedgehog in my garden. I had heard that you should always check the little guys for ticks (care for sick/wounded hedgehogs can be done for free in bird centers here), but as usual he ran off almost immediately.

When I went to Wikipedia, to my amazement I discovered that hedgehogs are not to be found in the USA at all! Does the average US'er even know what a hedgehog looks like?

Anyway, are there any other surprisingly non present animals ( in parts of the world with about the same climate and flora, I am not surprised there are no elephants here).

Evilbu 14:18, 3 August 2006 (UTC)[reply]

Yes, there are many. Australia is a great place to find unique animals that could survive elsewhere, but haven't really ventured out into the world. As for Americans and hedgehogs, there is a small group of people in the U.S. that own domesticated hedgehogs as pets. However, most couldn't tell the difference between a hedgehog and a porcupine. Finally, the trick to picking up hedgehogs is to scoop them from both sides. I face them as I do so, I think it is less traumatic (though it has to be frightening to get picked up) if they see it coming. They will roll into a ball and make a lot of huffing and popping noises. After a long time (I've had it take over 10 minutes), they will relax. Of course, it is actually easier to inspect them as they are rolled up in a ball than it is to inspect them when they are relaxed and the quills are laying flat. --Kainaw (talk) 14:30, 3 August 2006 (UTC)[reply]
Of course I know what a hedgehog looks like..
--64.12.116.74 15:20, 3 August 2006 (UTC)[reply]
or this one --64.12.116.74 15:20, 3 August 2006 (UTC)[reply]
I was extremely surprised to find out recently that there are no Skunks in Africa, Europe and most of Asia. You don't know what you're missing.--Anchoress 19:27, 3 August 2006 (UTC)[reply]
Anybody want to trade hedgehogs for skunks? I'd take a hedgehog infestation any day over the tyranny that skunks have. As Darwin wrote of them: "Conscious of its power, it roams by day about the open plain, and fears neither dog nor man. If a dog is urged to the attack, its courage is instantly checked by a few drops of the fetid oil, which brings on violent sickness and running at the nose. Whatever is once polluted by it, is for ever useless." --Fastfission 19:32, 3 August 2006 (UTC)[reply]
Talk to Standing Bear. He has a lot of hedgehogs. Of course, he will want to ensure you give them a nice home. --Kainaw (talk) 19:46, 3 August 2006 (UTC)[reply]
One obvious animal present, just, in the UK but not in similar habitats in the U.S.A. or, as far as I know, elsewhere outside Europe is the Red Squirrel. That though is because the, more aggressive & less attractive, Grey Squirrels outcompete them. AllanHainey 15:03, 4 August 2006 (UTC)[reply]

What kind of Praying mantis is this?[edit]

Can anyone help me find the latin name for this particularly beautiful Praying mantis? It was uploaded to Wikicommons by a French speaking user, who labelled it a Sudanese mantis. But I haven't been able to find any other pictures of Sudanese mantises, I'm not sure whether that is the actual vernacular name or just a description (a mantis found in Soudan). Help would be appreciated. Do you think it could be Blepharopsis mendica? --woggly 15:48, 3 August 2006 (UTC)[reply]

Soudanese Mantis
It looks a lot like this fellow, who is a young Blepharopsis mendica, I think (the page it is from lists it as a "larva"). --Fastfission 19:30, 3 August 2006 (UTC)[reply]
Hmm. Yes and no. The eyes are angled differently from the head, but that might just be a difference in the angle of the photograph... I'd really like to know, because I want to nominate this for a featured picture, and for that it needs to be illustrating the proper article (not just Praying mantis - there are too many other good pictures there). Anyway, it wouldn't be a larva, but a nymph. Thanks for finding that picture, which is the closest I've seen so far! --woggly 19:59, 3 August 2006 (UTC)[reply]
I've loooked at more Blepharosis mendica pictures, and I don't think this is it. The Blephs all seem to have mottled eyes and long antennae, whereas this guy has distinct "pupils" and short or no antennae. Still looking... more ideas would be appreciated. --woggly 05:42, 4 August 2006 (UTC)[reply]

Logo or symbol or abbreviation for engineers[edit]

Is there any internationally recognized logo or symbol for engineers? e.g. red cross for doctors.What is the short title for an engineer(Er or Ir or Ing) e.g. Dr for doctor.

I've only seen "Eng." used. It is rarely used alone. For example, I am a CSciEng, not an EEng. Then, some drop the "ng". EEng is often just EE. --Kainaw (talk) 17:27, 3 August 2006 (UTC)[reply]
For an international title there would have to be an interntionally accepted exam, at least that would make sense. Then again, dr is indeed rather international, without there being international exams (afaik). Btw, Ir and Ing are Dutch. Are you? Or are these titles used elsewhere too? DirkvdM 19:33, 3 August 2006 (UTC)[reply]
I don't know of any internationally recognized logo but in context something like a gear would probably be recognized by most people. --Fastfission 21:31, 3 August 2006 (UTC)[reply]
The closest thing to an 'official abbreviation' will be a variant of P.E., which at least in the US stands for Professional Engineer. It is used after one's name, as in John Doe, P.E. But it wouldn't be used in typical day-to-day correspondence, only in situations where the title would be familiar to the audience. If our John Doe wrote a letter to the editor of the newspaper, he wouldn't include the P.E. after his name; but if he was authoring a report commissioned by a client of his engineering firm, then he would.
In India, I have seen people use Er. as the abbreviation for engineers (So I should be Er.Wikicheng :-) ), though it is not very common. Electrical_Engineer#Engineer.27s_degrees_in_Europe has some abbreviations of other countries which may belp--Wikicheng 05:08, 4 August 2006 (UTC)[reply]
In Canada, the common abbreviation for a professional engineer is P.Eng. in English and, I believe, Ing. in French. I think that Ing. is also used in Germany. As far as logos or symbols, there's no clearly accepted symbol, particularly since engineers do so many different types of work. I've seen a cogwheel, chains, the beaver and the Vitruvian Man used, but not universally. In Canada, the Iron ring is understood as an engineering symbol. --ByeByeBaby 06:53, 5 August 2006 (UTC)[reply]

Hepatitus c and Vitiligo[edit]

i am looking for advice how to treat a Vitiligo (1 year) if have a Hipatitus c (5 years).

  • Vitiligo and Hepatitis C may have some useful information about each condition, but for a real answer, you should see a doctor. (Note the statement at the top of this page: "If requesting medical...advice, please consider asking a doctor...instead.") -- Scientizzle 19:59, 3 August 2006 (UTC)[reply]

cat with neurological problem - stroke?[edit]

He had a temperature of 104 F at the beginning, now gets around slowly and shakily, barely responsive to stimuli, licks soft food, doesn't drink without bottle help, wants to put his head into corners, has forgotten how to use litter box. Does anyone have ideas for rehabilitating a cat who's had a stroke, or something like it? --Halcatalyst

That doesn't sound like a stroke. That sounds like sickness. He should go to a vet. After a stroke, cats have trouble moving, usually the back legs. They don't curl up and wait to die. --Kainaw (talk) 19:27, 3 August 2006 (UTC)[reply]
A veterinarian. --198.125.178.207 19:28, 3 August 2006 (UTC)[reply]
Was that a useful addition? What's this tendency to point out the blatantly obvious, even when that was already done by the previous poster? DirkvdM 19:38, 3 August 2006 (UTC)[reply]
It was added before I noticed Kainaw had already added his veterinarian comment. Note the similar edit times. And the obviousness of the comment isn't really relevant. It is the best possible advice. --198.125.178.207 19:46, 3 August 2006 (UTC)[reply]
We did take him to a vet and he was in the hospital for several days. They eventually diagnosed a neurological disorder and released him to our care. They said they had never seen anything like this and also suggested it might be time for euthanasia. We're hoping there might be something to be done to help him recover. --Halcatalyst 19:40, 3 August 2006 (UTC)[reply]
(As I've mentioned many times, I work in a hospital, so I can ask random doctors for advice - but do not consider it binding advice as I'm just a comptuer programmer)...
According to a doctor here, if it was a human he would first send it to MRI to test for pressure on the brain. Then, he would send it to GI to have the intestines checked. Because of the fever, he suspects a viral infection. --Kainaw (talk) 19:44, 3 August 2006 (UTC)[reply]
The vet at first thought it was a gastro-intestinal infection, but the tests came back normal. And he hasn't improved on the antibiotic (which we're still giving him. He's also on prednizone. --Halcatalyst 20:08, 3 August 2006 (UTC)[reply]

I know how it feels to see your pet going through suffering. I can't help you with the treatment, but I wish you the best of luck. --mboverload@ 23:22, 3 August 2006 (UTC)[reply]

I agree. My last hedgehog had very similar symptoms. On Monday he didn't eat much, but kept running around like normal. On Tuesday, he didn't want to run. He just curled up by me and kept sleeping, so I made an appointment for the vet on Wednesday. On Wednesday morning, I got him up to check on him and he was the same. I got dressed and went back in and he had passed away. Later, I found out he had multiple cancerous tumors in his intestines. I was frustrated because I had taken him to the vet a month earlier and he got a clean bill of health. I felt like the vets didn't take it seriously because it was a hedgehog and not a dog. There is a lot of emotion involved - pain, sorrow, anger. I now feel that I should have listened to my doubts about the first vet and gone to a different one. Keep finding a different one until you find one that isn't just going through the motions to cash a check. I'm sure there are a few vets out there that take the job seriously. They are just hard to find. --Kainaw (talk) 13:26, 4 August 2006 (UTC)[reply]
I'm not sure that was a redundant addition. In some parts of the world vet is not commonly the abbreviation for veterinarian; but for combat veteran. Many of them are hungry, but that doesn't mean they will want your cat. Notinasnaid 13:55, 4 August 2006 (UTC)[reply]
My mentor is an immunologist (PhD) and vet (DVM), and he agrees that given the information supplied that the source of the cat's neurological symptoms is most likely suffering an infection. He also highly recommends that you look around for possible sources of the infection: other animals contacts (wild or otherwise), and the like. Possible contagion to or from other animals is a very serious consideration (though it is highly unlikely that the pathogen is infectious to humans). – ClockworkSoul 19:02, 4 August 2006 (UTC)[reply]
  • Because of the high temperature, the vet[erinarian] ran a full set of tests, which were negative. Nevertheless, the cat has been on antibiotics for ten days now. In a week, he has urinated a couple of times and only one very liquid bowel movement.
  • Thank you all for your interest. Poor Ozzie is worse these last two days; he can't get around at all anymore, but he is eating soft food ravenously. He can't drink by himself (it's as if he doesn't know what water is), and I hope I'm getting him enough hydration. He doesn't appear to be in any pain. --Halcatalyst 01:44, 6 August 2006 (UTC)[reply]

Ref Desk Archive Problem[edit]

I keep on ending up on an archived page accidentally. It seems when I edit certain questions on an active Ref Desk page I end up in an archived page, after I finish. Does anybody know what's going on here ? It has been happening for quite some time, but only happens, say, 10% of the time. StuRat 20:50, 3 August 2006 (UTC)[reply]

How do you get out from the archived page into the real world again? One can't make a phone call from a page. --LambiamTalk 21:24, 3 August 2006 (UTC)[reply]
Weird, I thought I answered this earlier.It's because you are editing a section from an archive that is transcluded onto this page. When you edit the section and save, it sends you to the page that you actually edited. Actually, if you hit 'edit this page' at the top instead of just a section, you'll easily see that the first few days displayed on this page are transclusions of archives. Hyenaste (tell) 01:37, 4 August 2006 (UTC)[reply]
So why do we do that ("transclude" archived pages that appear to be on the active ref page) ? I would think they should either be on the active page or the archived page, not somewhere in limbo between the two states. StuRat 05:34, 4 August 2006 (UTC)[reply]
Ready to learn easy maintenance tricks ? OK, listen : never listen to complaining customers (I admit this only occurs in sci-fi stories about horrid old admins with tentacles). --DLL 15:29, 4 August 2006 (UTC)[reply]

Physical basis of the Mendelian ratios?[edit]

What's the physical basis of some genes being dominant and recessive? Is this well understood at the moment? I poked around the pages which looked most relevant here (recessive gene, dominant gene, Mendelian inheritance, classical genetics, molecular genetics) but saw nothing about this. I'm just curious, that's all. Is this a universal function of all DNA-carrying organisms? I can see the evolutionary advantage of recessive genes but it surprises me that all organisms have them—one could hypothetically imagine DNA that dealt with only dominant genes. Which would lead me to think that either the ability to have recessives is so basic and advantageous (in a way I don't understand) that it would have outpaced a dominant-only arrangement early on, or it is closely related to the basic functioning of DNA in a way I don't understand. Anybody have a clue? --Fastfission 21:22, 3 August 2006 (UTC)[reply]

What they taught me in college is that there's actually a spectrum of dominance, from completely recessive to completely dominant and everything in between. The physical basis is simply the body's reaction to different amounts of protein. If you have two copies of an allele, you'll have about twice the resulting protein as if you have one copy. If the body needs the full amount for whatever function, then having only one copy will mess you up, and the disease-causing allele will be dominant. But if the body only needs a little bit, so that 1X or 2X the amount makes no difference, then the disease-causing allele will be recessive (you only need one copy of the good allele, meaning to be sick you need both copies of the bad allele). There are examples, though I can't quote them off my head, of diseases where having one good copy and one bad copy will cause a disease, but having two bad copies will cause a more serious disease or even prevent the fetus from developing at all. The article you need is Dominance relationship, but I just now found that after writing this, so I hope I'm on-base. --Allen 21:40, 3 August 2006 (UTC)[reply]
An example would be sickle cell anemia, where one sickle cell gene causes mild symptoms, but also provides partial immunity to malaria. Two sickle cell genes, on the other hand, cause a serious and often fatal version of the disease. StuRat 05:30, 4 August 2006 (UTC)[reply]
I assume you understand that for most human genes, every person normally has two copies of each type of gene, one copy from each parent (see: diploid). Here is an analogy for a recessive disease: think about human vision. If you have damage to one eye, you can still see fairly well with just one functioning eye. For many genes, if the copy from one parent is defective, the biological function that is normally accomplished by that type of gene can be accomplished using just the one good copy from the other parent. In order to seriously disrupt the function of that type of gene, you need to have inherited mutated versions of the gene from each parent. For many dominant gene mutations, having one normal copy of the gene from one parent cannot compensate for the problem caused by having one copy of the mutant gene. Some proteins coded for by mutant genes have been shown to function at the molecular level as "dominant negative" regulators of cell processes. In some cases, even a very small amount of altered protein from a mutant gene can have dominate effects over the normal protein. Often this is the case because many proteins normally exist in an "inactive" conformation. Such proteins normally do nothing inside cells until something special happens to activate them and as soon as the special condition is over, the protein goes back to being inactive. In many cases, dominant mutations in the genes for such proteins result in a version of the protein that is always on. This over-activity can cause a disease condition, even if half of the proteins of this type are normal (produced by the non-mutated copy of the gene. Analogy: think of fire sprinklers. If 50% of the sprinkler heads in a building had a defect that made them activate at room temperature, that building would have a problem. Even if only 1% of the sprinkler heads had this defect, most building owners would object. Dominant mutations are often of this type....the mutant gene codes for a protein that causes trouble. --JWSchmidt 22:18, 3 August 2006 (UTC)[reply]
Those are interesting and good descriptions, thanks. It's a bit more complicated than the classical genetics approach usually makes it out to be. --Fastfission 15:19, 4 August 2006 (UTC)[reply]

Bromine and its effect on swimsuits....[edit]

Hello....I swim several times a week for fitness and have noticed that I need a new swimsuit about every three to four months...sometimes I swim in a pool with bromine instead of chlorine...is bromine more caustic to swimsuit material than chlorine??? Just curious...thank you for your time...Jane----

According to this site bromine is less caustic than chlorine and "will not fade bathing suits or yellow blonde hair". It would appear chlorine is used for economic reasons rather than functional ones. Perhaps you should swim more regularly in the bromine treated pool and see if your swimsuit degrades at the same rate. Rockpocket 00:07, 4 August 2006 (UTC)[reply]
(after edit conflict) As an isolated element, Bromine is actually less chemically active than Chlorine and, based on a little research, the bromine compounds commonly used in swimming pools appear to be less damaging to hair, skin, and bathing suits than chlorine. Bromine is often the sanitizer of choice in spas and hot tubs as it is more resistant to very hot water. --Nebular110 00:15, 4 August 2006 (UTC)[reply]

hormones[edit]

Please explain the origin and function of gherin, i.e. what stimulates its release, what tissues make it, and what tissues are targets.

First, please explain the function of homework (this sounds like homework to me). Next, try searching for gherin and hormone in your favorite search engine. If you have questions needing to clarify anything you find, feel free to come back and ask them. digfarenough (talk) 23:06, 3 August 2006 (UTC)[reply]
Perhaps you mean ghrelin? Rockpocket 23:34, 3 August 2006 (UTC)[reply]

gastro-enteritis[edit]

what is gastro enteritis?? i hav tried looking it up heaps of times but there isnt anything. i know that it is something that can happen if you are poisoned but i want to know wat it acctually is. for ex. vomitting, dizzynous, etc. any help would be greatly appresiated --Sammie hero 23:08, 3 August 2006 (UTC)[reply]

Does the page on gastroenteritis not help? (Perhaps your extra space or hyphen in the word is making it harder to find information). digfarenough (talk) 23:09, 3 August 2006 (UTC)[reply]

oops thank you heaps i didnt even think of that

I've set up from redirects from gastro enteritis and gastro-enteritis to the main article. --Canley 06:47, 4 August 2006 (UTC)[reply]