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

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Xbox 360 hard drive

On my Xbox 360 I am unable to save my music from my flash disk to the hard drive as the 360 doesn't let me save music that isn't on my hard drive. I also can't even access the videos on my flash disk via my 360. How can I get these on the hard drive? Thanks. schyler 00:37, 3 June 2006 (UTC)

Souring of Milk

What substance causes milk to sour and eventually spoil? Is it yeast?Patchouli 01:15, 3 June 2006 (UTC)

No, it's lactic acid bacteria, turning the sugar in the milk into lactic acid. See milk#Curdling for more info. --Bowlhover 02:09, 3 June 2006 (UTC)

Are there free hard drive recovery options?

A friend of mine just called and asked if I knew of any free/cheap hard drive recovery tools available. I can't think of any off hand -- I recommended one of the many services available. He doesn't really want to pay, of course. Is there software available that would assist him in recovering data from a "Dead" hard drive? Thanks! --65.4.235.198 03:33, 3 June 2006 (UTC)

This is a windows partition, by the way, and he is not comfortable at all with Linux. --65.4.235.198 03:37, 3 June 2006 (UTC)

This depends a lot on what kind the damage is, what might have caused it and what is the file system on the drive. From my experience as a fan of the classic FAT, I'd say a skilled self-taught guy could perhaps figure a thing or two out. We'd need more information to help you with the problem. --Ouro 18:34, 3 June 2006 (UTC)

If he were willing to use Linux, I could offer some advice — a live Linux recovery CD really is one of the most versatile recovery tools in existence. I went through this process myself some years ago, and wrote up my experiences here. Of course, the specifics depend on the type of damage the drive has suffered. However, regardless of the damage and the recovery tools used, the most important rule is the same: first make a disk image. Having obtained the image, make a backup copy of it (your new drive is probably big enough). Only then, when you have two full copies of the data on reliable media, should you start trying to fiddle with the filesystem and such things. That way, even if you accidentally overwrite the image you're working on and the original drive bursts into flame, you still have a full backup of all the data. —Ilmari Karonen (talk) 21:40, 6 June 2006 (UTC)

Toes

Is there a techical term for those black hairs that sprout on your toes? Vitriol 04:21, 3 June 2006 (UTC

Animal hair is subdivided into different types based upon size, shape, position and colouring (these are called awls, auchenes and zigzags), but terminal human hair is classified by body position. Thus hair on your head is defined by where it is on your skull (e.g. parietal hair), hair around the genitals is pubic hair, hair under your arms is axillary hair and the hair on your fingers and toes are called digital hairs [1]. See Hair#Types_of_hair for more info. Rockpocket 08:38, 3 June 2006 (UTC)

Also called digital era. --DLL 20:36, 4 June 2006 (UTC)

Ability to Self-Update to New Versions in Linux Distributions

I run Ubuntu in a virtual machine, and was happy to note that the updater that Ubuntu uses to patch, update, etc. is capable of downloading and installing new versions of Ubuntu (right now upgrading from 5.10 to 6.06 LTS) into itself, essentially an in place upgrade. Are any other Linux distributions capable of this? I have previously used SuSE, but via YaST, I was only able to update or upgrade components, I could never upgrade the entire operating system. Thanks. MSTCrow 04:39, 3 June 2006 (UTC)

On Debian, one can type apt-get update; apt-get upgrade and it downloads and installs new versions of all components, including the kernel. (Which is not surprising, since Ubuntu is based on the Debian architecture.) –Mysid^(t) 05:34, 3 June 2006 (UTC)

Are the upgrade mechanisms of Ubuntu and Debian identical, apt-get, synaptic etc.? --vibo56 09:28, 3 June 2006 (UTC)

In many ways. Ubuntu uses apt-get/aptitude/synaptic to upgrade and dist-upgrade, but uses its own repositories for packages. ❝Sverdrup❞ 01:38, 6 June 2006 (UTC)

In fact, it may even be possible to upgrade a Debian system into Ubuntu (or vice versa) with apt-get dist-upgrade. Of course, this is not likely to be a very well-tested upgrade path, so some breakage is likely, but it probably can be done as long as you're prepared to fix any unexpected configuration issues manually. I know I personally did this long ago with another Debian-based distro (Storm Linux), dist-upgrading it into Debian (woody, I think). Other than a few X-related issues (all display managers got uninstalled in the process) it was surprisingly painless. —Ilmari Karonen (talk) 21:52, 6 June 2006 (UTC)

wearing heel shoes

is it true that wearing high heels is actually fatal?how?

I'd certainly advise against it if you're planning on going tightrope walking. GeeJo ^(t)⁄_(c) • 09:31, 3 June 2006 (UTC)

..or horse riding, climbing, scuba diving, running (whether being persued or not), hiking, etc. For an explanation of some of the risks, see high heels. --Shantavira 11:36, 3 June 2006 (UTC)

There was this casefrom 1999...

sleeping birds

why dont birds fall off the tree while sleeping?

A part of the brain remains active while sleeping, allowing some functions (like breathing) to remain active. Many animals retain brain function that allows them to keep their balance and enough muscle activity to remain standing. See the article on sleep, in particular the section on "animal sleep". Weregerbil 09:16, 3 June 2006 (UTC)

For birds that sleep gripping a branch: Bird claws are actually "designed" so that the pressure from the weight of their bodies actually pushes the claws closed, making it take little effort to keep holding on.—Pengo 10:14, 3 June 2006 (UTC)

The birds you're describing are known as perching birds, or passerines. Their feet actually have a "locking" structure to keep them holding on to things without voluntary control. Psittacines sleep while perched as well. --Ginkgo100 19:37, 3 June 2006 (UTC)

life on mars?

i heard that mars has polar ice caps just like earth.so does this create a possibility of life on mars?

thank you

Water ice may help life survive. Nobody knows whether there is life on Mars. The article life on Mars and its references and external sources has a great wealth of information on the subject. Weregerbil 09:11, 3 June 2006 (UTC)

The martians know...

MSTCrow 19:50, 3 June 2006 (UTC)

Itching

Hi, I I've been having this itch for about a month that has been killing me. My anus itches, and its not all the time, just sometimes, and its driving me nuts. I thought it might be pinworm, so I got something called pin-x yesterday and took it. I'm not sure if thats the problem though. It still itches. I dont have any other problems, no blood or anything, any ideas? Thanks

I'd say you have an acute case of Pruritis Ani, and I'm sure most doctors would agree. But seriously, if you're worried, see a doctor. It's very unlikely to be anything, but it couldn't hurt. And never trust medical advice you were given by a random bunch of people on the internet. GeeJo ^(t)⁄_(c) • 09:36, 3 June 2006 (UTC)

Pinworm infection is one of the commonest causes of Pruritis Ani Pruritus Ani, and is something that you can treat yourself. I'm not familiar with the brand-name "pin-x", but the generic names of the substances used for treating pinworm infection are given in the article. If you chose to diagnose and treat it yourself, be sure to read the instructions that follow the medication. Two rounds of treatment are necessary because the medicine does not kill the eggs. Pinworm is sometimes difficult the get rid of, because of self-reinfection through eggs, both from clothing or bed-sheets, and via the fecal-oral route. Therefore, when taking the medication, you will do wisely in also changing underwear/pyjamas/bedsheets, and in observing meticulous hand-hygiene. --vibo56 (Random guy on the internet) 10:49, 3 June 2006 (UTC)

Actually most doctors would refer to it as pruritus ani because you can't have inflammation of an itch. The pruritus is the itch-- you might recognize its cognate, prurient. And while pinworms are a common cause in children, the cause of pruritus ani in adults is rarely so simple to diagnose and treat. alteripse 23:29, 3 June 2006 (UTC)

Thanks for spotting the error. Actually, I believe that all doctors would refer to it as pruritus ani. --vibo56 09:34, 4 June 2006 (UTC)

There are lots of causes of anal itching, not just pinworm. Candida overgrowth (yeast infection) can erupt in the gut as well as the vagina, with similar results. Also, even a temporary drop in hygeine can leave you with itchy, irritated skin. An ingrown hair near the anus can also cause itching. If the pinworm meds don't work and you don't want to see a doctor, try gently washing the area three times a day with mild soap and water, and carefully drying. Also go to the drugstore and pick up some anti-yeast cream and/or a suppository (talk to the pharmacist, don't just pick something up from the aisles). You might also consider trimming (NOT SHAVING) the hair in that area; sometimes bacteria or moisture trapped by the hair can cause itch. And finally, VD can cause anal itching, and can be contracted either through unprotected anal sex or analingus.--Anchoress 01:36, 4 June 2006 (UTC)

TV static

I'm wondering for years where TV static such as [2] comes from. I'm sure it is some form of noise (radio), but still this doesn't explain why an analogue TV ends up having hectic black and white dots jumping around the screen. What are the technical reasons for this effect? Thanks, --Abdull 10:26, 3 June 2006 (UTC)

Background radiation in the Universe is postulated as one source of electromagnetic static as well as various local sources of electrostatic radiation from naturally occuring radioactive isotopes contained in virtually all objects including our own bodies. ...IMHO (Talk) 11:24, 3 June 2006 (UTC)

Okay... your answer may explain where background noise comes from, but this is not what I was asking for: my question was, why does this noise cause a TV screen to create snowy images? Maybe it is because of noise amplification, but I'm not sure. --Abdull 11:51, 3 June 2006 (UTC)

I guess the TV set just interprets the noise as a luminance signal, and that's what it looks like – random-brightness dots here and there. It being black-and-white may be due to the fact that the NTSC and PAL chrominance signal is sent using quadrature amplitude modulation, which is unlikely to be heard in random noise. The dots jump because the screen is refreshed constantly, even though there is no broadcast. –Mysid^(t) 13:01, 3 June 2006 (UTC)

This already sounds pretty straightforward. I wonder there isn't a single website that discusses TV static. Therefore it'd be great if there was a wiki article. --Abdull 13:29, 3 June 2006 (UTC)

Agreed. I'll take a picture of our TV with static and start a stub later today :P though I don't know much, as you can see. It's getting rare with all this digital TV thing. –Mysid^(t) 14:10, 3 June 2006 (UTC)

Well, after searching I found this: noise (video). It says static is not random. –Mysid^(t) 14:17, 3 June 2006 (UTC)

Right. Static usually refers to electrostatic discharge or electrical sparks casued by everything from light and appliance switches to lightning. Because they accompany specific events they are not in general considered random unless the event is considered random as well. ...IMHO (Talk) 20:30, 3 June 2006 (UTC)

It only refers to interference as being non-random. The article really needs some help. It doesn't even mention background radiation.—Pengo 00:01, 4 June 2006 (UTC)

Industrial Engineering

pleaze tell me about the work of Industrial Engineers in textile industry and tool factories.

Is there specific information you need? Why are you asking? Do you want to become one, do you need to write an essay on them, ...? Take a look at industrial engineering. Weregerbil 12:28, 3 June 2006 (UTC)

Buckminster fullerine

Hi, i was wondering whether it is possible to create another spherical carbon arrangement, other than Buckminster fullerine. What would the empirical formula be? Would this have use in nanotube techonolgy?

Thanks chemaddict 11:18, 3 June 2006 (UTC)

Why do you think it might be impossible? ...IMHO (Talk) 11:28, 3 June 2006 (UTC)

What?!!

Yes, what's behind that rude retort, IMHO? Chemaddict clearly thinks it's possible, to the point of asking questions in an effort to prove such things could exist. Please don't bite the newbies. JackofOz 11:44, 3 June 2006 (UTC)

I doubt it. Have you read our article on buckminsterfullerene? --Shantavira 11:47, 3 June 2006 (UTC)

This article states it's possible, and gives a picture of C₅₆₀ as an example. Conscious 16:39, 3 June 2006 (UTC)

The scientist is not a person who gives the right answers, he is one who asks the right questions. - Claude Levi-Strauss and this (I like quotes). --Ouro 18:29, 3 June 2006 (UTC)

What's meant by the question? Can you have balls with more or less carbon atoms than C60? Yes. But they're still fullurenes then. Or do you mean getting with different ring shapes? Then I'd say probably not. Either the ring stress is too high (5 or 4-carbon rings) or it's planar (6-carbon rings - i.e. graphite). --BluePlatypus 18:37, 3 June 2006 (UTC)

I hate to say this, but the empirical formula of any form of pure carbon is just - C.--G N Frykman 20:35, 3 June 2006 (UTC)

I think you will find the emprical formula for diamond is C yet for buckminster fullerine and graphite it is not.

I quote from empirical formula: "An empirical formula makes no reference to isomerism, structure, or absolute number of atoms." 60/60 = 1. Perhaps the learned (unsigned) gentleman (I can't imagine a lady would be so abrupt) would speculate as to what the empirical formula of graphite is? C infinity? G N Frykman 20:47, 3 June 2006 (UTC)

Why has my question sparked so much fury, it was just a question, for i am trying to learn about the world i live in. The unsigned person is partly correct yet partly wrong. The emphirical formula for buckminster fullerine is C60. Diamond is C and so is graphite. The reason Buckminster fullerine is not C, is because it has a define structure. Layers of graphite, as you point out, are infinite but the structure of Buckminster fullerine does not but remains in balls of 60 carbon atoms.

chemaddict 11:40, 4 June 2006 (UTC)

I'm sorry if my going into teacher-mode sounded like fury. I was just responding to what I considered to be an incorrect interpretation of the phrase empirical formula. When applied to buckminster fullerene, a much more useful phrase would be molecular formula. The relationship between empirical formula and molecular formula caused 19th century chemists a great deal of anguish, and the difference only became apparent when a reliable way of determining the M_r (molecular weight) of a substance could be found. G N Frykman 16:29, 4 June 2006 (UTC)

chemaddict - You are incorrect. The definition given by Frykman is correct, the empirical formula for both graphite, diamond and any fullurene (including C60) is simply C. Just because graphite and diamonds are crystal structures does not mean that they have an "undefined" structure. There's also a whole nomenclature for crystallography out there, although that's not relevant to what "empirical formula" means. The official IUPAC definition being: "Formed by juxtaposition of the atomic symbols with their appropriate subscripts to give the simplest possible formula expressing the composition of a compound." Note that it says "composition" not "structure". --BluePlatypus 01:31, 5 June 2006 (UTC)

sorry mate, we're not all Oxbridge graduates who like to advertise their degrees on the WWW because we are so insecure with ourselves that we want to boast that we have been using a mass spectrometre on the cover of the oxford prospectus

To add to pedantry :), I'd like to state that no fullerene is spherical. Polygons may be a good approximation of a sphere, planets too.

Another question would be - is it possible to have such spheroids not made of carbon, silicium maybe, did somebody try ? --DLL 20:31, 4 June 2006 (UTC)

Fullerines are made from hexagons and pentagons like a football, please explain to me how this is in any way, not spherical?? chemaddict 21:33, 4 June 2006 (UTC)

Thank you to the (still-unsigned) gentleman who is using this thread to mount a personal attack, seemingly inspired by my extra-Wikipedia home page. For the record (a) there is no such thing as an Oxbridge degree, and there is therefore no need to boast about it, nor to feel insecure (b) the contributor should check the spelling of mass spectrometer (c) the picture was not on the front cover (d) it was nearly 30 years ago (if that is of any relevance) (e) it would have to have been quite a small machine to have been able to use it on the front cover... G N Frykman 21:59, 4 June 2006 (UTC)

I didn't know that you had a teapot. And it was broken before you lent it to me. --DLL 22:08, 5 June 2006 (UTC)

Online Streaming of english music

Can you give me the site names which offer online buffering/streaming for listening to english songs with out downloading on to the harddisk?

Thank you

List of Internet stations, perhaps? Melchoir 16:58, 3 June 2006 (UTC)

Or use iTunes (link), hundreds of streaming stations listed by genre. --hydnjo talk 18:09, 3 June 2006 (UTC)

Have you tried XMradio.com? XM 16:05, 7 June 2006 (UTC)

le chatelier's principle

what is le chatelier's principle

cheers

matt

Why not just look it up? Le Châtelier's principle Femto 11:46, 3 June 2006 (UTC)

Bloody hell old boy, give the lad a break! Someone wake up on the wrong side of bed. Matt, Le Chatliers Principle is "If a chemical system at equilibrium experiences a change in concentration, temperature, or total pressure, the equilibrium will shift in order to minimize that change." Hope this helps and if you ever want some extra help please do not hestiate to contact me! All the best, Dr J Parker.

It's not a question of giving people breaks, or wrong sides of beds, Dr Parker. It's about having an efficient system with a reasonable set of rules that make life work best for everybody. Where the information they're after is readily available, they should be directed to it in the first instance, and then if they have further specific questions they can come back here. Femto did exactly the right thing. The very first instruction we give to users is: Search first ... Search Wikipedia using the searchbox. It looks like your answer came word for word from our article. Well, if Matt had searched first as directed, he could have read that for himself without any need for an intermediary. It doesn't take a doctorate (of whatever) to be a messenger boy. Also, if Matt wants to take you up on your invitation to contact you for further information, how would he do that? You're not a registered Wikipedia user, so the only way would be to contact you on this page, where all of Wikipedia can see it and join in. (Private conversations are not appropriate or even possible on a reference desk page.) Why not get yourself a username, and learn some of the basic Wikipedia procedures, before pontificating from the outside about the behaviour of members of a group you've not even seen fit to join, despite hanging around for a couple of years now.JackofOz 03:32, 4 June 2006 (UTC)

carbon emissions

hi, i appreciate that any answer to this question will be in some senses conjecture but, is there a correalation between the amount of carbon humans emit and the severity of climate change that will ensue? basically, i guess i'm asking, is it a legitmate argument to say, "once we're emitted x many tonnes of carbon, climate change will happen, so we should just let rip" or should we always keep reducing emissions ad infinitum? (could climate change skeptics please not respond) thanks! --87.194.20.253 11:50, 3 June 2006 (UTC)

climate change is continuous. It has already begun. The mass of Carbon has always been in the earth, but due to the industrial revolution and the increased use of fossil fuels, millions or years worth of carbon are being released into the atmosphere. The increased amount of carbon (dioxide) that we, as a race emit, the more of an effect it will have on global warming. To minimise and in some ways where possible reverse the effect of global warming, we need to reduce our emissions and start to use alternative methods of power generation such as nuclear, geothermal, solar etc.—chemaddict 12:31, 3 June 2006 (UTC)

Adding to QuantumChemistryFan, we don't know how strongly carbon dioxide concentration affects the climate either. It may just be fine and dandy, or it may be causing "climate change sure to kill us all off" you know, the possibilities. — The Mac Davis] ⌇☢ ญƛ. 13:06, 3 June 2006 (UTC)

That said, it's a reasonable working hypothesis that in general, the greater the change to the atmosphere we make, the greater the change to the climate. That's why the consensus seems to be that we should aim to cut carbon emissions as much as we reasonably. --Robert Merkel 16:40, 3 June 2006 (UTC)

It becomes an economics issue, much like nuclear radiation. Should we forget about bird flu and put all resources into carbon reduction? etc. Is there a 'safe' limit? Do we lower our standard of living to do this? Right now, there is a gradual approach to do things that are reasonable, such as carbon taxes, etc. We will probably never have as much success with this, as with the ozone hole. --Zeizmic 13:39, 3 June 2006 (UTC)

Bare in mind, due to severe reduction of CFCs and the introduction of HCFC's as a replacement, the ozone depletion has been reversed and in the next 50 years the ozone layer should be 'patched up'. However, it will be interesting to see what effect this has on global warming as ozone is a greenhouse gas, albeit more predominately in the troposphere.chemaddict 20:35, 3 June 2006 (UTC)

Has it? [3] — The Mac Davis] ⌇☢ ญƛ. 02:15, 4 June 2006 (UTC)

Yes, but CFCs were incredibly potent greenhouse gases themselves, as well as their effects on the ozone layer. See greenhouse gas. --Robert Merkel 02:31, 4 June 2006 (UTC)

To answer the last part of your question, please note that life on Earth would not be posible without greenhouse gases: the temperatures would be generally too low in most places most of the time. The problem is not to remove these gases, but to keep their concentrations within bounds of what we (humans) and nature (plants and animals) can adapt and adjust to the prevailing conditions. --Michel M Verstraete 13:03, 4 June 2006 (UTC)

Yes obviously, he means excess of greenhouse gasses chemaddict 16:24, 4 June 2006 (UTC)

BOTANY LIFESCIENCES

does the banyan tree release CO (Carbon Monoxide) ?

I wouldn't think so, not unless you set one on fire in an oxygen-poor area. StuRat 19:21, 3 June 2006 (UTC)

Banyan trees do not release CO under normal conditions.

Sciatic nerve damage?

About a month ago I hopped out of my chair and got the ol' sharp pain in my lower left back. Nothing unusual. That's been going on for decades. Only this time something back there clipped the sciatic nerve in my left leg. I was in some major pain for about a week.

Went to the doc. Saw the x-rays. No cartilage between the two lower vertebrae. The back is pretty much back to normal and I don't have much pain anymore but my lower leg is still numb and I have a hard time walking up or down stairs. The muscles in my left leg don't seem to be doing their job.

Therapy now consists of some sort of hot packs to the lower back and traction. No change. I live in a country where I don't speak the local lingo well and the doc does her best with English but....

I was wondering if anyone else has had this. Do I have a chance of getting the use of my leg back or am I hosed? Thanks.

Standard Medical Disclaimer. I had a bad bout of this a few years ago. It comes from sitting too much at a computer terminal and answering wiki-homework (or some such thing). Every person has to find their own path out of it. I did it through exercise and stretching, to get the back back to normal, since this all comes from a specific pinched nerve in the lower spine. If you ignore it, there will be a progression towards total paralysis. See a physiotherapist first for exercises, progress on to a back specialist doctor. There are 'quick' keyhole surgeries, and there are massive surgeries. I hope for the best. --Zeizmic 14:55, 3 June 2006 (UTC)

Thanks! That makes sense. Kinda scary, too.

chemistry

Sir/Madam,

I would like to know some of the common chemical substances that sublimes on heating.

Carbon dioxide and iodine – see sublimation (physics). –Mysid^(t) 15:35, 3 June 2006 (UTC)

Ammonium salts such as ammonium chloride.--G N Frykman 20:29, 3 June 2006 (UTC)

Hamsters

This is a better question than my other one about toehair (I hope).

Why do hamsters even have the potential to trust humans? Our domestication of dogs worked as dogs have complex social systems, but hamsters don't have any and see most other animals (including other hamsters) as enemies. I like to think my hamster trusts me, but how could this be? Vitriol 20:36, 3 June 2006 (UTC)

Hammsters have a social understanding, albeit to a small level. With time and the fact they have little choice(!) they will do in time. — Martin Alderson

Most mammals, with enough time and effort, can be trained by operant conditioning. They can recognise humans who handle them regularly. If they learn that a handler will not hurt them or will provide them with food or entertainment, they will associate those positive things with the handler. Positive reinforcement is the mechanism through which your hamster might "trust" you - his experience dictates that you care for him and provide him with positive stimuli. Rockpocket 21:02, 3 June 2006 (UTC)

Or consider projection or anthropomorphic fantasy. I find you can really tell whether someone trusts you by whether they will give you their email address or a loan. alteripse 23:24, 3 June 2006 (UTC)

I love my hamster ^_^ Vitriol 00:52, 4 June 2006 (UTC)

Clearly. But the trust/loyalty/affection at question here is the hamster's. alteripse 02:52, 4 June 2006 (UTC)