Wikipedia:Reference desk/Archives/Science/2008 January 25

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January 25

cardiac muscle tissue

i need to know what cell is cardiac muscle tissue is made out of. —Preceding unsigned comment added by 24.151.37.249 (talk) 01:53, 25 January 2008 (UTC)

Muscle cells are myocytes. The muscle cells of heart muscle tissue are called cardiomyocytes. But that's just "heart muscle cell" in Latin, so knowing the name may teach you something about Latin, but doesn't add to your understanding of the heart.- Nunh-huh 02:38, 25 January 2008 (UTC)

Gulls again...

The sea was very rough and very high this afternoon. The water was about 20 feet higher than usual, with some massive waves crashing down.

The water was also covered with hundreds of paddling gulls of various species, both large and small. They were getting absolutely hammered by the waves, tossed about like driftwood on the surface or getting covered by a couple of metres of foaming, churning water every few seconds and bobbing up the other side. Unsurprisingly, they didn't seem to be that bothered by it (gulls are hardy, waterproof seabirds, after all). The strange thing was that there were more gulls in the water on a day with the worst tides I have seen for years than there usually is on a 'normal' day. It was as though the gull flock had seen the state of the water and made a conscious decision to go for a swim *because* it was rough...

Any suggestions as to why? I did consider that the water may have churned up some tasty invertebrates from the seabed or confused some fish into heading to the surface but looking at the state of it out there, I'd be surprised if the gulls were able to keep still long enough to nab anything. --Kurt Shaped Box (talk) 02:35, 25 January 2008 (UTC)

Perhaps it's just being in their element – prefering to ride out the gusts on water than being knocked about on a cliff face – a bit like sailors who claim to feel safer at sea than on land, in a raging storm. You'd have to wonder about this claim in the light of conditions in some of the Sydney to Hobart yacht races[1], though. —Preceding unsigned comment added by Julia Rossi (talk • contribs) 10:02, 25 January 2008 (UTC)

urea again

wat mineral nutrient can i use to turn urea to a nitrate? —Preceding unsigned comment added by 76.14.124.175 (talk) 05:06, 25 January 2008 (UTC)

I'm not sure what you mean by "nutrient" to turn urea into a nitrate, but a strong oxidizing agent (concentrated hydrogen peroxide, nitric acid, permanganate) should be able to affect this transformation. As for more specific procedures, I can't give you any more information. Warning: strong oxidating agents can screw you over pretty badly, as can strong mineral acids.18.96.6.239 (talk) 05:17, 25 January 2008 (UTC)

somthing about bactiria, but anyways do u know were i can get the specifics? cuz being the scientist i am i'll try manual or no manulal! —Preceding unsigned comment added by 76.14.124.175 (talk) 05:22, 25 January 2008 (UTC)

Um, if you don't know what you are doing you're going to blow your fingers off making urea nitrate. It's highly explosive and very dangerous and screwing up in making it can lead to lots of nasty results, if I recall correctly. --24.147.69.31 (talk) 22:13, 25 January 2008 (UTC)

science fair, please help

ok, the science fair is coming up and i need a realy good idea from some one smart and creative, —Preceding unsigned comment added by 76.14.124.175 (talk) 05:10, 25 January 2008 (UTC)

The Manhattan Project? More seriously, are Tesla coils still considered impressive? A robot doing something unique? Do you know anyone who'll let you do some recombinant DNA technology?

Atlant (talk) 13:13, 25 January 2008 (UTC)

If you want to win at the science fair, you need to know what is being judged. At most schools, it isn't "Who can build the most impressive thing with lights and sounds and bubbles..." It is "Who can form a hypothesis, test it properly, and draw a scientific conclusion from the tests." So, the "good idea" is simply a matter of forming a hypothesis that you can test in both a controlled and uncontrolled environment. A common example is to get 10 feeder mice or goldfish. Form a hypothesis about how changing something in their natural environment will affect them. Put half in the normal environment and half in the controlled environment. Do your best to scientifically measure the change in the mice/fish. At the end of the experiment note how the observations either met or failed to meet your hypothesis and draw a conclusion. For example: What happens if half the mice get sugar water as a treat three times a day and the other half get Splenda-water three times a day? What if you do it with 3 getting normal water, 3 getting sugar water, and 3 getting Splenda water? -- kainaw™ 13:37, 25 January 2008 (UTC)

Of course, then you've got a lot of mice left over to figure out what to do with. --24.147.69.31 (talk) 16:15, 25 January 2008 (UTC)

Free Willy Free Mickey? jeffjon (talk) 16:44, 25 January 2008 (UTC)

If it were me, in this day and age, I would probably not try to do some tired old natural sciences experiment, but try to do something a little more in the realm of the social sciences. An example of the sort of thing I am talking aout: Find a few kids who are described as "popular" by your peers. See if they are willing to participate in a experiment regarding fashion and memes. See if they will wear some new article of clothing that won't look absurd but is not something they or their peers currently wear. See if they will help you track how many other people start wearing the same thing, and who they are. Are they close friends or more distant? Are they "popular" people or not? Etc. Consider ways in which you could use the internet as a big experimental pool — can you drive traffic to a meaningless page? How so? From what sources? What seems to work best? (Google Analytics, or similar software, would help you get the numbers of that sort of thing). Anyway, I think something like either of those would look a lot more fresh than the old "where does mold grow" sorts of things that they've been doing for decades. Even something as mundane as "how do people at my school use the internet?", with lots of boring surveys (and then see if the IT people at the school can get you some raw, anonymous data to see if the trends match up with how people report), can be trussed up much more interestingly than a lot of the sorts of natural science experiments you're going to be able to come up with, because frankly most of that low-hanging fruit has long since been picked. --24.147.69.31 (talk) 16:58, 25 January 2008 (UTC)

Here's a good project: try to answer this question posted right here on this very Reference Desk!

I'm quite serious; this would be very easy to do using ordinary materials you have around the house. It would be a perfect application of the scientific method, and you'd be quite likely to learn something new, some facts generally unknown outside of perhaps a toaster manufacturer's secret internal lab. —Steve Summit (talk) 15:41, 26 January 2008 (UTC)

OK, I'm feeling charitable, so I give you a winner for free. My daughter's project was judged "outstanding" at her high school and regional science fairs and went to the state fair. She implemented a Michelson interferometer using really cheap components and techniques. she demonstrated that her piezoelectric positioner could reproducibly move a mirror to any position across six wavelengths of red light. She hacked a $2.00 piezoelectric buzzer to get teh actuator, and she drove it using two nine-volt batteries and a potentiometer. Her light source was a $1.00 lazer pointer, and most of the mirrors were plain old cosmetic mirrors. The only "lab-quality" components were a very small "beam-splitter" (a half-silvered mirror) and a very small front-surface mirror. She recorded the results using a webcam connected to her computer. She built her own optical bench instead of buying one, using plain old nuts and bolts to perform coarse and fine alignment. The beauty of this is that you ger spectacular results for very little effort. WARNING: even $1.00 laser pointers can be dangerous to your eyes. Learn laser safety before you use a laser pointer: I would like to fire most of the marketing department of my company because the idiots use the damn things without understanding the safety issues. -Arch dude (talk) 03:19, 27 January 2008 (UTC)

Subconsciousness

When was the first idea of their being a human subconsciousness? —Preceding unsigned comment added by 74.138.83.10 (talk) 05:13, 25 January 2008 (UTC)

Unconscious mind should be able to answer your question. --S.dedalus (talk) 06:54, 25 January 2008 (UTC)

Posting at multiple desks is a no-no, 74. See policy top of this page. Julia Rossi (talk) 10:13, 25 January 2008 (UTC)

is there any sensor that checks the intensity of light

s there any sensor that checks the intensity of surrounding environment light —Preceding unsigned comment added by Chandar86 (talk • contribs) 12:27, 25 January 2008 (UTC)

In the general class of photodetector we find photoresistors ("photocells"), photodiodes, phototransistors, and solar cells will all do that. Turning to more obscure devices, there are photomultiplier tubes, photo-TRIACs, and all of the image sensors used in cameras. And photographic film and the retina in your eyes, of course, but those are probably not what you had in mind.

Atlant (talk) 13:14, 25 January 2008 (UTC)

Light meter used by photographers?--TreeSmiler (talk) 01:20, 26 January 2008 (UTC)

Spectrophotometer? Zrs 12 (talk) 02:27, 31 January 2008 (UTC)

Old people leaving the gas on

My grandmother can't leave my grandfather alone for long periods because he has a tendency to leave the gas going on the oven. Is there some device that will prevent this from happening or perhaps emit a warning when the gas has been on for an extended period? ----Seans Potato Business 12:54, 25 January 2008 (UTC)

The obvious solution is to get an electric stove. However, there are many gas detectors you can purchase. -- kainaw™ 13:30, 25 January 2008 (UTC)

If the gas is left on and lit, a gas detector is unlikely to be of use. DuncanHill (talk) 13:40, 25 January 2008 (UTC)

Most modern gas appliances have a heat sensor and will turn off or right down if left unlit. I think this is mandatory on new ones sold in the UK but I have no idea about elsewhere. But as you say left lit is more of a problem--BozMo talk 13:45, 25 January 2008 (UTC)

That's also one of the most expensive solutions. Especially when you consider that electricity costs three times as much per unit energy. The gas is indeed left while lit. ----Seans Potato Business 14:26, 25 January 2008 (UTC)

I suggest getting a carbon monoxide detector as gas ovens are not usually vented. This habit sounds fairly harmless to me, but how long is a long period? If his wife lives with him, as implied, perhaps address why he needs to turn the oven on at all? To keep warm?--Shantavira|^{feed me} 15:47, 25 January 2008 (UTC)

Maybe he cooks? DuncanHill (talk) 15:57, 25 January 2008 (UTC)

On a state pension, leaving the gas on is not harmless! And of course its for cooking. A "long period" is however long it is until his wife notices that the gas has been left on. The point is, his wife doesn't want to have to always be with him. ----Seans Potato Business 18:58, 25 January 2008 (UTC)

Shantavira suggests a carbon monoxide detector. First, gas that you burn for cooking may not contain carbon monoxide; that depends on where you live. In many countries it is natural gas, which is pretty pure methane. Second, carbon monoxide detectors are intended to prevent poisoning. With fuel gases, the main risk is explosion, and conditions of detection may be different. See under the item #Gas leaks above!

The obvious solution does seem to be to replace the stove with one that will not allow dangerous amounts of gas to accumulate. I would expect this to be true of any modern gas stove, but if you aren't getting an electric stove then you should talk to people who know about the gas regulations in the country where you live. I would start by talking to the gas company. --Anonymous, 20:19, edited 20:22 UTC, January 25, 2008.

Carbon dioxide is not necessarily part of the gas supply; rather, it is produced by incomplete combustion (combustion without sufficient oxygen). Burn pure methane in a poor supply of oxygen and you'll get lots of carbon monoxide (and some carbon dioxide). Burn pure methane in a good supply of oxygen and you'll get lots of carbon dioxide (and other products), and relatively little carbon monoxide (but you'll still get some). Angus Lepper^{(T, C, D)} 23:55, 25 January 2008 (UTC)

Well, sure (except you meant "monoxide" the first time). But we're not talking about carbon monoxide formed that way. --Anon, 01:50 UTC, Jan. 26.

Forgive me if this causes pain. Most people in you grandfather's situation are suffering from middle-stage Alzhiemer's disease. This is progressive, so most people in this situation will not be able to continue cooking for very long. Thus, a solution that costs a lot or that cannot be implemented immediately is probably not worthwhile. That said, every day you can gain for your grandfather is good, so let's look at the science. If I understand the problem, he is leaving the stove lit. Adding hardware to the stove itself is going to be expensive, so you should think about a separate heat monitor connected to an alarm. If you grandfather cannot respond to an alarm and shut off the gas, then I fear that he should not be left alone. You can create the alarm system with a computer and some thermometers or thermostats, or with a computer and an infared videocamera. The videocamera is probably easier since it need not be attached to the stove. The solution (computer+camera+software) will be a good deal cheaper to configure and install than just about any special-purpose equipmetn, and you can re-purpose the components later as needed. No, I do not know of any specific software to do this, but you can probably get someone to hack something up quickly. any junk computer (free or less thatn $100 used) can do the job. Most cheap ($20) webcams can be hacked to sense infrared by removing the infrared filter, or yuo can buy a cheap "security" webcam taht does not have the filter in the first place. Your "image recognition" program will simply look for the hottest spot in the image: trivial. The program is also trivial: If the hotspot exceeds a threshold for too long a time, play an audion alarm. If the hotspot persists for another 15 minutes, the computer can call a telephione number or send a test message. There is a huge amount of free softwrae infrastructure for this: google Misterhouse. -Arch dude (talk) 02:46, 27 January 2008 (UTC)

There actually are devices for this. They detect motion and will turn off if someone is not in the room. Sorry, but I don't remember the names. I know consumer reports reviewed a few of them a while ago (year or two maybe). They are pretty expensive. Ariel. (talk) 08:04, 28 January 2008 (UTC)

Hangover, sleeping position dependent

Whenever I enjoy a few drinks, if I lie with my head facing left my head-ache/head feels a lot more painful than if I lie with my head facing the other way. This is during the night after having had some drinks. Anybody any ideas why this would be? —Preceding unsigned comment added by 194.221.133.226 (talk) 13:17, 25 January 2008 (UTC)

For lack of experts as yet, I'll guess you could look at Carotid artery or the Jugular vein (see diagrams) since these major blood vessels are in the neck and pressure might affect them, do you think? Then there's the hangover and red wine headache articles. Since the hangover article is dense language, go for the talk page discussion. Julia Rossi (talk) 02:16, 29 January 2008 (UTC)

what is the areodynamic function of flaps

The position of the leading edge slats on an airliner (Airbus A300). In this picture, the slats are extended.

A close look at the spoiler (the parts of the wing that are raised up) during the landing of an Airbus A321.

I know that flaps are used to control a plane better while landing and takeoff , but if it is so useful then why can`t we use it on the whole flight .What is arrodynamic secret behind flaps and do they work--Man manoj1990 (talk) 13:56, 25 January 2008 (UTC)

Flaps increase both the lift and the drag of a wing. More lift means better control at low speeds (particularly landing; most planes use less flap when taking off), but more drag means more fuel used. At cruising speeds, the lift is unnecessary and the fuel is expensive. — Lomn 14:47, 25 January 2008 (UTC)

Yep. It's easy to notice this yourself, if you can see the wing from where you're sitting. It's very noticeable when the flaps go all the way up- they make lots of noise and slow the plane down in a hurry. Friday (talk) 16:00, 25 January 2008 (UTC)

Please don't confuse flaps with speed brakes and spoilers. Flaps extend rearwards and downwards, move slowly, and usually involve rather-noisy jackscrews. The increase the overall curvature of the wing. Spoilers are panels that hinge upwards and move rather quickly. Speed brakes tend to increase drag but not change lift; I don't think you'll see them much on commercial aircraft. You may also notice slats, moving elements similar to flaps but on the front of the wings.

Atlant (talk) 17:21, 25 January 2008 (UTC)

Very true, flaps are not the same as air brakes. Nevertheless, Friday is correct that flaps do have a slowing effect, especially when applied by a novice pilot too quickly. The reduction in speed is a useful effect when landing as well as the increase in lift. SpinningSpark 22:09, 25 January 2008 (UTC)

It's not really a matter of "better control at low speeds", but of not falling out of the sky at low speeds. The purpose of flaps on a fixed wing aircraft is to reduce it's stall speed (V_s). As the speed of an aircraft is reduced the angle of attack must be increased in order to maintain level flight. If that angle is increased beyond a certain critical limit, then all of a sudden the wings stop generating any lift at all, the aircraft is no longer flying but falling. This is called a stall and is not a good thing to have happen when you are near the ground, such as during a landing.

Flaps change the shape of the wing's airfoil (increasing the camber), generating more lift at lower angles of attack but at the cost of increased drag. Extended flaps allow the aircraft to fly a slower and steeper approach and landing, safer and less wear and tear on such things as struts and tires. For the rest of the flight, you usually want to go as fast as possible, you want a "clean" configuration with minimum drag, and the flaps are unnecessary.—eric 01:38, 26 January 2008 (UTC)

Hydrocodone

Can hydrocodone be taken with other medications such as augmentin? —Preceding unsigned comment added by Jokerkace88 (talk • contribs) 16:12, 25 January 2008 (UTC)

Question and answer removed per our no medical advice policy. I suggest you see a pharmacist or doctor about this as we are not qualified to give you advice about possible drug interactions. You should always inform your doctor and pharmacist about any drugs you are already taking when getting a new prescription so they can advise you appropriately. Nil Einne (talk) 20:02, 25 January 2008 (UTC)

Note that you can usually look up known drug interactions pretty easily. Just google the name of the drug and the word "interactions" and you'll find a lot of information. But call up a pharmacist -- they'll be able to tell you very quickly and it shouldn't cost anything. Note that if you ever have questions about medication you are taking, your pharmacist is required by law (in the US, anyway) to chat with you about any concerns or questions you might have. (Hopefully by not trying to "answer" but merely explaining how an answer might be found, this won't violate the rather draconian enforcement of the no-medical-advice policy.) --24.147.69.31 (talk) 22:08, 25 January 2008 (UTC)

Bear in mind of course you can easily misunderstand the data as published which is one of the reasons pharmacists usually have to go through 3 years of more of education plus on the job training before being able to advise people on what they should or should not do with their medication Nil Einne (talk) 15:01, 26 January 2008 (UTC)

Errm ... I'd just like to point out that, as phrased, the questioner is asking for medical information, not medical advice, so there is no reason to remove question or answer. If they had asked "Can I take hydrocone with other medications ?", then that would have been a medical advice question - but that wasn't what they asked, and we shouldn't jump to conclusions about the intentions behind questions. Gandalf61 (talk) 10:13, 26 January 2008 (UTC)

It's the same thing. We always err on the side of caution with medical advice Nil Einne (talk) 15:01, 26 January 2008 (UTC)

It's definitely not the same thing. We have very clear and precise guidelines about what constitutes medical advice. Wikipedia:Reference desk/guidelines/Medical advice defines medical advice as a diagnosis, a prognosis or a suggested form or treatment. None of these are present in this question. Wikipedia:Reference desk/guidelines/Medical advice also says "Note that questions may be about a medical topic ('What is sleep apnea?', for example) without necessarily seeking medical advice, and this is acceptable". This is the category that this question falls into. There is no evidence that the questioner is asking for advice on medication that they or anyone they know is actually taking. Gandalf61 (talk) 16:49, 26 January 2008 (UTC)

And one like this can easily be solved by pointing to one of the many websites which include a list of drug interactions for hydrocodone. Or just google for "hydrocodone interactions". Information != advice. --jpgordon^∇∆∇∆ 16:08, 27 January 2008 (UTC)

Moon and Sun visible at the same time

The lunar phase.

Is there a term for when both are visible in the daytime sky? —Preceding unsigned comment added by 207.141.1.129 (talk) 22:45, 25 January 2008 (UTC)

I don't think there is a specific term. That said, moon is only visible during the day at certain phases. On the diagram to the right we can see that the full moon will always rise at sunset. However the waning crescent moon is high overhead around 9:00 AM local time and visible from sunrise to around 3:00pm. The waxing crescent is overhead at 3:00 PM and visible from around 9:00 AM to sun set. The new moon could be seen all day if it wasn't for the fact that the dark side was facing us. So, If you wanted to define when the moon and the sun are both visible, you could say it is between the third and first quarter of the lunar phase. Rockpocket 08:15, 26 January 2008 (UTC)

The above response contains a number of statements that are not quite right, but which I don't feel like addressing individually. I believe it is correct that there is no specific term for when the Moon and Sun are both visible in the daytime sky, though, and that covers the question asked. --Anonymous, 21:47 UTC (daytime, but neither Moon nor Sun is visible at the moment), January 26, 2008.

Obviously my response is not accurate when describing the visibility of the sun and the moon at any given point on earth, since the earth is 3D, a sphere, and the diagram I have used to demonstrate the principle is 2D, a circle. The times will different by season, of course, and by latitude and so the definition I offer is specific only to this simplified diagram, it would differ for pretty much every point on earth. Its so kind of you, anon, to take the time to point out that there are flaws but not to specifically identify or correct them. Most helpful. Rockpocket 22:09, 26 January 2008 (UTC)

Well, the correction I'll note is your phrase "[the] moon is only visible during the day at certain phases". A better phrase, in my opinion, is "the moon is visible during portions of the day depending on the phase" -- as you go on to note, it's not that the moon is never visible during the day in one phase* and then suddenly visible during the day in the next but rather that the window of visibility changes continuously.

*Abstracting out axial tilt and what not, the moon is always above the horizon at the same time as the sun at some point during the day. At full moon, half a solar disc is on the horizon directly opposite half a lunar disc. Careful observation will certainly reveal that even first- and third-quarters aren't a practical limit; the moon is visible at significantly closer angles, though solar glare starts presenting a major obstacle. — Lomn 20:46, 27 January 2008 (UTC)

trippyfans and turkey

is it true that turkeys evolved their trippyfan acids to disable predators who tried to eat them by putting them to sleep after a large meal —Preceding unsigned comment added by 172.162.124.144 (talk) 22:46, 25 January 2008 (UTC)

That wouldn't really help the turkey. You can read about it here. Someguy1221 (talk) 23:30, 25 January 2008 (UTC)

phenogenomics

There is an institute of phenogenomics near my doctor's office in downtown Toronto. What do they study there? (email address removed) —Preceding unsigned comment added by 76.68.73.214 (talk) 23:05, 25 January 2008 (UTC)

email address removed Joe^Talk_Work 09:36, 28 January 2008 (UTC)

You mean this one?

The centre will be creating and identifying mouse models of human disease using a number of strategies with the ultimate goal of understanding how these diseases work in humans, who possess similar genes

You may be interested in model organism. Someguy1221 (talk) 23:35, 25 January 2008 (UTC)

From the description, it is a portmanteau of phenotype and genomics and is pretty much specifically meaningless. However, if you give your facility a cool, futuristic tech-driven sounding name, people tend to give you more money. Rockpocket 07:56, 26 January 2008 (UTC)

The website for the Toronto Centre for Phenogenomics is here. If you click on the 'About Us' link in the navigation menu on the left site you can get a general overview of what they do. The 'Research and Support' link will take you to a more detailed list of projects and facilities.

Per Rockpocket, phenogenomics is a portmanteau of phenotype and genomics. I gather that they're working systematically through the entire mouse genome, mutating (or knocking out) genes (the 'genomics' part) and looking to see what effect each mutation has on the mouse (the 'phenotype'). The facility is supposed to house more than a quarter million mice when in full operation. TenOfAllTrades(talk) 17:18, 26 January 2008 (UTC)