Wikipedia:Reference desk/Archives/Science/2007 March 10

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1 March 10

[edit] March 10

[edit] new technology

dear sir,

  please tell me about new inventions & research works.

—The preceding unsigned comment was added by 202.88.252.28 (talk) 04:19, 10 March 2007 (UTC).

Dear sir, please make this question a little more specific. Thank you. − Twas Now ( talk • contribs • e-mail ) 07:05, 10 March 2007 (UTC)

There are a number of magazines devoted to this type of info, such as Popular Science. I'd go to the library and look through those mags, if I were you. Another option is to go to any news site, like CNN, and look through their science section. StuRat 00:11, 11 March 2007 (UTC)

Technology? This question is wide open. Nimur 19:50, 11 March 2007 (UTC)

Intriguing question! According to this page, the 44 newest inventions are:

--TotoBaggins 15:19, 12 March 2007 (UTC)

I never knew there were so many plants being "invented" Capuchin 13:16, 13 March 2007 (UTC)

[edit] Dove behavioural experiment

I have once read about a behavioural conditioning experiment with doves. They were given food at random intervals. The doves thought they were rewarded for their behaviour and developed individual bizarre routines and movements in order to get the food. Does anybody have a reference about this experiment. Thanks, Cacycle

Take a look at B.F. Skinner#Superstition in the pigeon. --JWSchmidt 05:30, 10 March 2007 (UTC)

The pigeons might develop a habit like turning circles clockwise, or head bobbing in a seeming belief that it would make the food come. Then consider people who have lucky routines. Basketball Coach Adolph Rupp of the University of Kentucky would reportedly have to buy a pack of gum from the same stand and get a fresh towel from the supply room before each home game for good luck. If a person does something once (like wear a certain shirt before a test) and a good result occurs (like a good grade) it can become the "lucky exam shirt" to be worn to all tests even 30 years later. Not a bit more logical than pigeons. Edison 03:54, 11 March 2007 (UTC)

Presumably if they're still taking exams 30 years later, a new lucky shirt might be in order. :) --TotoBaggins 15:22, 12 March 2007 (UTC)

[edit] What happens to the old heart

After a heart transplant,What happens to the heart that was removed.In other words what happens to the old heart. —The preceding unsigned comment was added by 68.161.97.103 (talk) 05:03, 10 March 2007 (UTC).

This is undoubtedly going to be answered by someone with more expertise, but I do know the cool fact that when you get a kidney transplant, the new organ is placed in the body without removing the old organs; the old kidneys stay in place. As my friend said, "They should really call it a kidney plant, not a kidney transplant." 65.96.181.140 22:06, 10 March 2007 (UTC)

They don't always transplant entire organs, in the case of the kidney, you can transplant sections of tissue, which are presumably grafted onto the existing veins and arteries^{[citation needed]}. Although, if you want to know more, we do have an article on kidney transplantation--VectorPotential^Talk 22:17, 10 March 2007 (UTC)

You're thinking of livers, I think, where transplants of a partial organ are very common. A partial kidney transplant would be much rarer. - Nunh-huh 22:26, 10 March 2007 (UTC)

I thought that sounded wrong (: hence the {{fact}} template. In that case, we also have articles on liver transplantation and heart transplantation--VectorPotential^Talk 23:49, 10 March 2007 (UTC)

The removed portions of the (old) heart are sent to the pathology department for histological examination. They are then disposed of, either by incineration as medical waste,, or by other means (e.g. burial, usually because of religious beliefs).. - Nunh-huh 22:15, 10 March 2007 (UTC)

[edit] When will Wikiprotiens be avaliabale to the public?

Um, not sure if we have anything on wikiprotein, let alone wikiprotien...but we have wiki protein articles. This will be available to the general public... on... Tuesday? Nimur 19:51, 11 March 2007 (UTC)

[edit] Motorola RAZR battery Comparison

Which of these batteries would be better for the RAZR phone

1:BR50 2:BC60

--logger 06:11, 10 March 2007 (UTC)

Well, the BR50 is a 3.7 volt lithium ion battery, whereas the BC60 is a 3.7 volt lithium ion battery, if there is any difference I can't imagine what it is--VectorPotential^Talk 13:28, 10 March 2007 (UTC)

All right then i might as well stay with the BR50. Its the Mah i am trying to figure out.--logger 17:02, 10 March 2007 (UTC)

They might be different in capacity, size, operating parameters, where their made, design (maybe one is mor elikely to blow up), level of finishing... Nil Einne 20:45, 13 March 2007 (UTC)

The form factor of these batteries is most definitely different [1] [2]. You should buy the one suitable for your variant of the RAZR Nil Einne 20:49, 13 March 2007 (UTC)

[edit] Spider picture: request species identification

Species: ????

It appears to be of the genera Nephila (also known as the golden silk orb-weaver), though I am no arachnologist − Twas Now ( talk • contribs • e-mail ) 07:24, 10 March 2007 (UTC)

Hi. Can someone identify what species (common name is fine) this spider belongs to? I need it to write the caption. Many thanks. Saravask 07:02, 10 March 2007 (UTC)

--Kjoonlee 08:53, 10 March 2007 (UTC)

Thanks, guys. I think genus name will do for now; if someone presses me for the binomial name, I'll post the image to the BugGuide page. Saravask 18:56, 10 March 2007 (UTC)

[edit] lecithin

I take lecithin daily as a vitamin; Are there any after effects generally noted?72.71.186.177 14:15, 10 March 2007 (UTC)

Our lecithin article doesn't list any direct side-effects, but does say that lecithin derived from eggs may contain cholesterol, and, of course, you need to limit that. StuRat 00:02, 11 March 2007 (UTC)

I have noticed lecithin-smelling urine at times with high doses (40-45 grams), don't know if it means anything. -User: Nightvid

[edit] Battery power

How come a 12 volt car battery is much more powerful than another 12 volt battery, such as one in a tractor or motorcycle? —The preceding unsigned comment was added by 24.231.205.94 (talk) 15:53, 10 March 2007 (UTC).

Because Voltage and Electrical power aren't the same thing? Power is the "rate at which electrical energy is transmitted" and voltage is the "difference of electrical potential between two points of an electrical or electronic circuit". Where power is defined in watts, voltage is measured in Watts per Ampere, which is a unit of power per current--VectorPotential^Talk 16:30, 10 March 2007 (UTC)

The car battery can probably sustain much higher currents and thereby deliver more power. The basic reason for this is that the car battery is larger and can store more chemical energy (assuming the tractor and motorcycle batteries are of similar chemical makeup). -- mattb @ 2007-03-10T23:26Z

A smaller battery might have the same chemicals and the same number of cells, but a smaller plate area, than the car battery. Edison 03:56, 11 March 2007 (UTC)

[edit] CCD arrrays

Isn't the output from a CCD array pretty much continuous such that shutter speed on a digital camera is pretty much a function of how many contiguous frames are recorded for a single snap shot? Diligent 17:43, 10 March 2007 (UTC)

No. A CCD can be used with a long exposure time, before reading it out. Of course, if a camera is built mainly for video, the designers might choose to use a fixed video-rate exposure time, in which case one would have to add images to simulate a longer exposure time, as you said. But still cameras are not made that way. --mglg_(talk) 18:36, 10 March 2007 (UTC)

Are you saying that digital still cameras then are made like conventional cameras where there is a mechanical shutter? What about digital combo still/video cameras? Diligent 18:51, 10 March 2007 (UTC)

DSLRs definitely have mechanical shutters, while most consumer digital cameras have electronic shutters. --antilived^{T | C | G} 02:08, 11 March 2007 (UTC)

Thats odd. I would think electronic shutters superior to mechanical. Maybe its just a traditional thing. Diligent 06:10, 11 March 2007 (UTC)

The thing with electronic shutters is that they take up real estate on the CCD cell. Each photodiode that collects light has an accompanying shift register. After the photodiodes have collected light for a specified time, their values are instantaneously copied (shifted) into the shift registers. The camera will then start reading the shift registers into memory. The camera can't read the photodiodes directly because that would take too long, and the diodes would keep on taking in light during that time.

In contrast, a full frame CCD has no shift registers. A mechanical shutter stops light from coming in, and the camera can read the photodiodes directly, at its own leisurely pace. Because there are no shift registers the chip area can be used for photodiodes instead of register electronics, and so can have more pixels and better sensitivity.

Maybe engineers will figure out better ways of putting in the shift registers, thereby closing the gap between electronic and mechanical shutters. Electronic shutters have nice features like lack of moving parts and the ability to capture video. For now, high end cameras have to do without those in order to get better image quality.

Here's a camera review that briefly discusses the issue: [3]. Weregerbil 11:43, 11 March 2007 (UTC)

Wow, great answer! --TotoBaggins 15:31, 12 March 2007 (UTC)

Yes and Thanks! Diligent 04:05, 13 March 2007 (UTC)

[edit] Nocebo Effect

I have read both the placebo and nocebo articles, i am unsure of my understanding of the nocebo effect though. Is it a pill to make someone feel ill? Or is it the patients mentallity when taking a placebo (unknowingly), that it won't work, so it doesn't.

I am sorry if the question is worded badly, the whole thing is kind of a mess in my mind, thanks in advance for any answers.

88.111.82.185 18:47, 10 March 2007 (UTC)

Arrgh, I lost my lengthy answer from network problems. In short, nocebo bills are like placebo pills. They shouldn't do any harm themselves. It's the patient's mentality when taking a nocebo pill that it will do harm, so harm comes. Not really from the pill, but from the patient's thinking. --Kjoonlee 20:33, 10 March 2007 (UTC)

The article says it's the reaction, not the pill or substance. It also says that the pill is called the same thing, whether it results in a helpful or harmful response. So you get a nocebo effect from a placebo. (If somebody tries to sell you "genuine nocebo pills", throw them away! Get the real fake pills.) Clarityfiend 20:34, 10 March 2007 (UTC)

Obecalp^TM, the Genuine Placebo. Trust no substitute. TenOfAllTrades(talk) 23:57, 10 March 2007 (UTC)

Apply directly to the dyslexic forehead? Clarityfiend 08:49, 11 March 2007 (UTC)

[edit] Self-incompatibility in plants

Following a discussion in the Hebrew Wikipedia about whether or not each species should have its own article, the subject of the self-incompatibility article has also risen. Someone claims that this article should be split - as it relates to different mechanisms which are evolutionarily independent. One of the disadvantages of the current (merged) format, is that the S locus, described for different mechanisms in parallel, can be mistakenly conceived to consist of a single locus for all mechanisms. Do you think this article should be split? You are also welcome to state your opinion about the one species-one article idea, although Wikipedia's policy was already stated here: [4]. Thank you in advance, Gidip 20:17, 10 March 2007 (UTC).