Wikipedia:Reference desk archive/Science/2006 July 14

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[edit] CSS issue

I'm currently doing some template work at another wiki, and have come across a problem that my very limited knowledge of CSS won't fix.

I have a template that's currently aligned right (an info-box), as well as a template that's aligned center (a bottom-page link banner). They're both div-based, for the most part. The problem is that the very far right of the link banner appears to be overlapped by the info-box. You can see the issue here.

What I'd like is to set the CSS so that the link banner will render on the page further down from the info-box, so that there is no overlap between the two templates at all. Is there any way of getting CSS to do this? Or will I have to manually enter all the blank lines to do what I want to do on each page? -- Kirby1024 01:14, 14 July 2006 (UTC)

You might want to put computer-type questions on the Mathematics page, not the Science one. But then again, here I am. You should be able to use clear:both; in that case in the CSS for the linkbox. In any case, you should never have to enter a whole mess of blank lines; they may or may not be necessary for people with different window sizes than yours. What you want in terms of a line break is the (deprecated but still widely-used) <br clear="both" />. grendel|khan 01:40, 14 July 2006 (UTC)
Whoops, almost forgot, a fuller explanation is available over here. grendel|khan
If he put the question on the Math RD, he would have received a useless answer about the mathematics of detecting overlap in bounding boxes. Posting computer questions in the Science RD gets answers that you can use. --Kainaw (talk) 02:07, 14 July 2006 (UTC)
Thanks! I was unsure as to which help desk was appropriate, but I'd seen other computer questions further up, and thus had assumed. But thankyou very much for the information! -- Kirby1024 05:19, 14 July 2006 (UTC)

[edit] Can a camera flash cause a fire?

Once, I was taking a picture with my camera while wearing leather motorbike gloves. I put my hand over the flash to take the picture. When I shot the picture, my glove sizzled and sparked brightly and when I looked at my glove, there was a smoking little shallow hole (not all the way through the leather). It is still there on my glove.

However, I've been met with skepticism when telling this story.

Has anyone else experienced this, or beleives it to be likely or at least possible, and will back me up here?

Thank you.

--Asia

Under normal circumstances, a camera flash can't start a fire. However, if there's a short circuit, then sure -- a spark could ignite something. — Lomn | Talk 01:27, 14 July 2006 (UTC)
The old one-time-use flash bulbs could (and did) start a fire. Over time, they were encased in plastic, which was actually rather handy because you could plug a 4-6 bulb pack into the camera and take multiple pictures without changing out the bulb. Of course, that certainly not the type of flash bulb the questioner is referring to. So, I should just shut up and go to bed. --Kainaw (talk) 01:30, 14 July 2006 (UTC)
It seems rather odd what happened to you. --Proficient 04:18, 14 July 2006 (UTC)
Odd happens. DirkvdM 13:03, 14 July 2006 (UTC)
A rather sadistic person I know made a "taser" with a camera flash, and the spark was enough to singe paper. It was also very painful I'm told... smurrayinchester(User), (Talk) 14:24, 14 July 2006 (UTC)
The bigger camera flashes put out many joules of light, easily enough to start a fire if concentrated on one spot. It would depend on the size of the flash capacitors. Also: I've seen a device which prints out contest win/lose ticks by heating some thermal-printer paper on the ticket using a photoflash tube. This paper typically turns black at around 100C.
Cameras use capacitors to store charge, and then release it in an instance, I know of disposable cameras which have capacitors capable of giving 300volt shocks. Philc TECI 23:35, 16 July 2006 (UTC)

[edit] Universal proxy

I'm looking for a simple freeware program for Windows that acts like a proxy for any protocol, and that lets me see the incoming\outgoing connections and what its being sent and received. I've been trying to find one but I can't figure the right keywords. :( Any suggestions? 201.48.96.40 03:19, 14 July 2006 (UTC)

Not exactly a proxy but if you want a packet sniffer then Ethereal (software) and its recent fork Wireshark are pretty popular ones. The packet sniffer article lists several others. Weregerbil 09:03, 14 July 2006 (UTC)
Yes! That's what I was looking for! Thank you ^_^ -- Anon

[edit] Cool as a cucumber

Apparently, the expression cool as a cucumber arose because the inside flesh of a cucumber can be up to 20° F cooler than air temperature on a hot day.

This sounds like a complete load to me, because I know what thermal equilibrium is. However, a quick Google just finds hundreds of pages saying the above and no pages actually explaining the mechanism for this astonishing thermodynamics-defying feat. Anybody know if it's actually true, and if so, how does it work? Cheers. Maelin 03:43, 14 July 2006 (UTC)

I suspect that it's because they came from somewhere cool, like the "root cellar" (this was before refrigeration), which was significantly cooler than the air temp above ground. Perhaps they are good thermal insulators, so hold the lower temp for quite some time. StuRat 03:51, 14 July 2006 (UTC)
Or because they're so gross when they're warm that they are never eaten unless cold.--Anchoress 04:05, 14 July 2006 (UTC)
Or cooked?  freshofftheufoΓΛĿЌ  05:02, 14 July 2006 (UTC)
Cucumbers contain a lot of liquid and maybe they 'sweat' just enough to stay cool without 'dehydrating'. DirkvdM 13:06, 14 July 2006 (UTC)
Evaporative cooling would be my guess too. On a dry day, its easy for an object to maintain a temperature lower than it's surroundings, while still abiding by the laws of Thermodynamics. See Swamp cooler for practical applications. Although fwiw, I've grown many cucumbers and never have I seen one 'sweat'. And, might I add, "Some people think cucumbers taste better pickled" --Jmeden2000 13:33, 14 July 2006 (UTC)
I agree, they don't sweat, especially when waxed. StuRat 22:16, 14 July 2006 (UTC)
I said " 'sweat' just enough to stay cool without 'dehydrating' ". In which case you wouldn't see the sweat - it evaporates instantly, without any excess visible. Also, are we talking about cut cucumbers? In that case the waxing wouldn't matter much. Assuming cucumbers are waxed, I never heard of that. DirkvdM 09:30, 15 July 2006 (UTC)
It's a widespread practice to wax them in the US, although you can also get them unwaxed. The waxed ones are shiny and the unwaxed ones are dull, that's usually the only way you can tell which are which. StuRat 14:58, 15 July 2006 (UTC)
Perhaps cucumbers contain a lot of water, which in turn has four times the specific heat capacity of air - perhaps it simply cools down at night, and takes a long time to heat back up... same would apply to oceans, watermelons, etc. - Saintmocha 03:20, 16 July 2006 (UTC)

Just a comment, note that in the old cosmological/scientific/medical theory of four elements and Four humours, cucumbers were considered to be a cool and moist vegetable and so useful for treating fevers. So "cool as a cucumber" may go back a long time Malcolm Farmer 15:57, 16 July 2006 (UTC)

The undeniable truth is that they are indeed noticeably cool. Even on a hot summer day in Australia, when lettuces are wilting and tomatoes are warm, sliced cucumbers keep their cool. I've never seen them sold refrigerated; cucumbers have the same storage arrangements as lots of other vegetables that are not as cool as them. JackofOz 01:59, 17 July 2006 (UTC)

[edit] Average age at which Americans lose their vrginity

I'm not sure whether this question should go under humanities or science, but where would I find credible studies about the age at which American males first have sex, on average? I couldn't find links to such information on wikipedia, and I'm not sure where else to look. Thanks.

Time magazine had this statistic in one of their 2005 editions. I think the median was around 15 or 16 (although this very much depends on the definition of sex). Raul654 04:28, 14 July 2006 (UTC)
The most unassailable source for data on American sexual behavior is unfortunately over a decade old now. It is the National Health and Social Life Survey, the only large-scale, statistically representative survey of American sexual behavior ever (that I'm aware of). You can find an overview here.
Two books came out of the project: "Sex in America: A definitive survey" is meant for the general reader and can be found in many libraries. "The Social organization of sexuality in the United States" is meant for academics, being chock full of statistical discussions and the details of survey design; of course it also has more raw data than the other book. You can find it at most university libraries and perhaps very large public libraries.
The General Social Survey, a long-time project of NORC, asks a few questions about sex (and many other interesting things you might want to read). You have to get the data yourself, though. Various sites make it available online. This is the survey's home page at NORC, which you might also find useful. --George 05:21, 14 July 2006 (UTC)

[edit] Can someone convert this into JPEG or PNG?

Well, yesterday I had put up a question about political world maps. Though volunteer "gadfium" helped me a lot. But the problem is that my computer is not very high end : 500MHz, 192Mb RAM. So the "svg" file, which I found very useful takes a long long time to open in Internet Explorer, and even after it opens, scrolling the image hangs up my computer. I searched google to find "svg" to jpg or png converter programs, bcoz I had to install svg viewer softwares or plugins to view that file. And being on dial-up connection, its difficutl to download a 15-18 mb application (the size of 3-4 programs which i found on internet).

So if someone could convert the following image to "jpg" or "png" format, it would be great help. I know I am asking for too much, but if someone could help me. After conversion, I wish the volunteer who does it provides a link to that image, either on wikipedia or on rapidshare (but no megaupload plz). The link for the image is : http://upload.wikimedia.org/wikipedia/commons/c/c2/World_map_pol_2005_v02.svg

Thank You - Nikhilthemacho.

Here: [1] --Ring0 06:56, 14 July 2006 (UTC)

Thank You very much, but how did u do it?

I used Inkscape - an open-source vector graphics editor [2].--Ring0 10:11, 14 July 2006 (UTC)
You use IE (and therefore msWindows) and your computer hangs. Gee, that's new. My suggestion is too obvious to make. DirkvdM 13:08, 14 July 2006 (UTC)
Then again, there's a less known reason, so I'll say it anyway. Linux was originally developed for 'small' computers (slow and with limited resources), so if that's what you have, Linux is the way to go. And you'll probably get a free image editor like gimp with it, installed by default. Out of the box functionality. And of course it's free. DirkvdM 13:10, 14 July 2006 (UTC)
An alternative way would just to let Wikipedia's image rendering software do it for you. If you pasted the following text into any window and clicked "Show preview" it would render the SVG as a 300px-wide PNG file for you to download: [[Image:World map pol 2005 v02.svg|1000px]] You can change 1000px to whatever you want. But don't "save page"—there's no reason to if you are just using this for your own purposes. --Fastfission 17:04, 14 July 2006 (UTC)

[edit] Network Printer

I just got a new laptop and a wireless connection in the same day. They both work beautifully, but im having trouble getting my printer, attached to another computer on the same wireless connection, to work with the new laptop. How do i do it? i tried to change the printer settings to allow for sharing. I looked aimlessly around the "my network places" folder of both computers. it should be metioned i have xp on both. the printer, if it matters, is an hp 3015 thanks

Details please. Have you gone through the "add a printer" process on the laptop? Are you getting error messages? --LarryMac 15:07, 14 July 2006 (UTC)
Make sure you have the latest drivers. --Proficient 17:17, 14 July 2006 (UTC)

[edit] Photon Belt

I would like to know if there was any reliable scientific information regarding the "Photon Belt".

Many new-age web-sites have made some rather interesting and way-out conclusions about what happens when it comes into range of Earth and i am understandibly skeptical about their claims. Most state that it will have/will encounter the Earth at some time between 1986 and 2012. This coincides well with end-of-days prophecies, millenium bugs and the dawning of the Age of Aquarius. The Belt's effects are said to be anything from a complete spiritual awakening, an Electro-Magnetic-Pulse phenomena to Psychic powers being awakened in Humans. I understand that these people are drawing information about the Photon Belt from a scientific source but i have been unable to locate any hard evidence myself. Thanks in advance.

Ways to defeat the photon belt:
  1. Wear sunglasses
I have lived through all the "end of the earth" shit. I don't see why that'll change anytime soon. --mboverload@ 08:03, 14 July 2006 (UTC)
  • "I understand that these people are drawing information about the Photon Belt from a scientific source but i have been unable to locate any hard evidence myself."

translates to:

  • "They have no scientific sources and are making it all up" Crazywolf 08:40, 14 July 2006 (UTC)
Making it up? In a political debate, lying or ignorance is perfectly acceptable if it lets us win.  :) But in a scientific debate the goal is to get to the truth, and if we're dishonest or ignorant, we'll defeat ourselves and lose the debate. So... suppose a widespread New Age belief exists which is based on "channeling." Suppose we lie about this, and insist that the New Agers are just making up the belief. (Or suppose we haven't even bothered to look into the issue, and we DON'T KNOW that the belief originates in "channeling.") Or suppose we try to turn the debate into a joke by sneering at it: "wear sunglasses." In that case we've discredited the skeptic position, and we're not to be trusted. The New Agers (and the greater audience) will scornfully dismiss us as ignorant liars, and rightly so. The arch-skeptic Ray Hyman of CSICOP has a bit about ways skeptics can turn their whole audience against them: [3] 'Especially' see #7 in his paper "Proper Criticism." Ridicule, sneering, and jokes at the expense of our opponents might make us feel good, but these are logical fallacies. They're common tactics in political debate, but are shameful when used in scientific debate.--Wjbeaty 15:10, 14 July 2006 (UTC)

C'mon people. Somebodies got to know more than NASA surely?--Twangus-Apparatus 09:00, 14 July 2006 (UTC)

Seems to me that the oddly titled The Photon Belt could do with some objective input and removal of a certain amount of nonsense (or just deletion).--Shantavira 13:02, 14 July 2006 (UTC)
About the photon belt we could say:
  • Channeling (mediumistic) doesn't work. All the received info just comes from the channeler's subconscious. (But this is a claim, and it requires evidence before we can accept it.)
  • or... there is no solid evidence that Channeling works. Whether it's real or not remains unknown, so we should ignore all "channeled information."
  • or... Channeling is real, but is not to be trusted. It easily lets evil entities spread lies and sow confusion, interfering with this world. If we believe in Photon Belt, it's at our peril.
  • or... Channeling is real, but some "channelers" have no ability, and their information is pure delusion. Yet there is no easy way to sort the reputable channelers from the mild psychotics. How can we tell if Photon Belt is a genuine warning or just a delusion? We can't.
  • or... if the world is about to end, and there's nothing whatever that we can do about it, then what good does it do to know the facts in advance? Should we all just commit suicide in order to avoid worrying about it?
--Wjbeaty 15:10, 14 July 2006 (UTC)

The only way to have a "belt" of "photons" is for them to be circling very close to a black hole. This is pure and utter bullshit. --mboverload@ 00:18, 15 July 2006 (UTC)

Regardless if The Photon Belt is "utter bullshit" or not, it's a part of pop culture and should not have been deleted... -Eep² 11:02, 6 April 2007 (UTC)

[edit] Label for particle mass

When, by whom and where was the first use of eV/c2 for mass? Thanks, 58.167.220.164 07:54, 14 July 2006 (UTC)

I think you need a really old physicist to answer this one. However this site [4] mentions that the eV was first used in 1912, I don't have access to the paper but I doubt that it gets used for particle mass as it is an article about the photoelectric effect. This letter [5] from 1940 which I do have access to is about a more consistent set of units and mentions that eV/c^2 is a derived unit for mass. So 1940 or earlier. JMiall 16:26, 14 July 2006 (UTC)

[edit] Angioplasty

Just curious - during balloon inflation in angioplasty, is the blood flow of the coronary artery in question is occluded? In that case, presumably the duration of occlusion is short enough for it not to be of concern? Thanks. -- Saintmocha 08:41, 14 July 2006 (UTC)

Yes, and yes. - Nunh-huh 08:56, 14 July 2006 (UTC)
Thanks :) -- Saintmocha 09:03, 14 July 2006 (UTC)

[edit] help pls...

pressure is equals to force by area ... if the force is human weight, how to convert it to force??

Mass in kg * 9.81 m/s/s = force of gravity Crazywolf 08:59, 14 July 2006 (UTC)
You might be helped by our article on weight. You are probably trying to convert units of mass to units of force, so the section on "Units of weight and mass": In general, to convert mass in kilograms to weight in newtons (at the earth's surface), multiply by 9.8. - Nunh-huh 09:01, 14 July 2006 (UTC)
Remember, what we normally call human "weight" is, in fact, mass - and what is the relationship between force and mass? Force might help. Remember, the acceleration in question is due to gravity, which is the reason for "9.8" keeps appearing everywhere. Good luck. -- Saintmocha 09:03, 14 July 2006 (UTC)

In the US, most people weigh themselves using pounds (Lb), this is actually a weight measure, as pounds are a measure of FORCE. In the UK, however, I have heard that people are sometimes measured in stones, which is in fact a measure of mass. In the rest of the world, humans are almost exclusively massed ("weighed") in kilograms, which is indeed a measure of mass. The SI measure of weight is the newton. Thus, pounds and newtons are measures of wieght (equivilent to the force of gravity on the person), and stones and kilograms are measures of mass.Tuckerekcut 17:01, 14 July 2006 (UTC)

Pound (mass) states that most of the time pounds is a unit of mass, not weight. - Dammit 19:44, 14 July 2006 (UTC)

I'm guessing everyone else read the question wrong, and you're really asking about the pressure on a person's feet. If you find the contact area of your feet with the ground, then divide your weight, in pounds, by that area, in square inches, you will get the average pressure, in PSI, on the bottoms of your feet (the part that touches the ground, that is). StuRat 22:37, 14 July 2006 (UTC)

You can find the contact area between your feet and the ground by stepping on watercolor paint, then graph paper. Count the number of squares covered with paint and multiply by the area of each square. StuRat 22:44, 14 July 2006 (UTC)

[edit] Windows XP - OEM vs Retail

I am in the process of buying the components for assembling myself a new computer, and, amongst many other things, I need a copy of Windows XP. Doing some shopping around (such as on Amazon.co.uk), I found to my surprise that many of the large retailers sell OEM versions of Windows. Some more searching around found me the license I'd have to adhere to, and reading through it, the main differences between the OEM and retail versions of XP seem to be that OEM is designed for 'system builders', it doesn't come with support, and that it can never be transferred to another machine once it's been installed and activated. I'm building a system and don't need support, so it seems like a good deal (for 30 quid cheaper, too!).

My two questions:

  1. As an individual assembling a computer for his own personal use, am I eligible to buy an OEM version? It appears to be geared towards people/companies who pre-install XP on custom-built machines for resale, and while a reading through the license, it doesn't seem to prohibit the use I'm planning to make of it - but I wanted to ask.
  2. How is 'can never be transferred to another machine' handled with respect to Microsoft's Product Activation? While I have no intention of using it on any machine other than the one I'm building, I am worried that if, in future, I swap out too many components (ie I do some upgrades), XP will refuse to run. I know that with retail versions, if this happens, you can call Microsoft and 'convince' them that, yes, the machine is still the same (with one exception), but this (from Microsoft) seems to suggest that, with an OEM version, this is not the case, and that too many hardware changes would force me to splurge out on yet another copy of XP.

Any help with these would be greatly appreciated :) — QuantumEleven 10:10, 14 July 2006 (UTC)

First, don't concern yourself with legal mumbo jumbo. Why do you care, it's cheaper. Go out and buy it, there's NO difference between the CD that comes in the box and the OEM one. --mboverload@ 10:57, 14 July 2006 (UTC)
Before recently, Dell stopped offering backup copies of Windows XP and only offered backup partitions which did not always work and were hard to activate. They have recently started offering backup discs. Anyway, we had to obtain a backup copy of Windows XP home four our desktop. We did get it and we were able to repair our Windows installation. Now, my laptop is licensed to use XP Pro, but as I said, it didn't come with a backup disc either. Instead of having to get another disc from Dell, I decided to reinstall Windows on my laptop using the same disc. It worked fine. Apparently the Dell OEM copies don't care how many times you install it. They don't ask for CD keys either. I also have a suspicion that the disc isn't even right protected, but I haven't had a need to copy it. --Russoc4 14:22, 14 July 2006 (UTC)
There is nothing to worry about. The OEM will work. As mentioned, many times a key is not even needed. --Proficient 17:19, 14 July 2006 (UTC)
From a legal use standpoint:
  1. you can purchase an OEM copy of Windows so long as you purchase meaningful hardware with it (a motherboard is Microsoft's suggestion). This is not enforced in practice.
  2. Again, the motherboard is the key "this is the original computer" component. MS will reactivate the OS by phone if you tell them you've replaced any other combination of components. They will also reactivate if you've had to replace the mobo with an identical model (due to fault/damage/etc) They may replace it even if you've upgraded the motherboard, as the whole mess is, in practice, loosely enforced for single-license copies. — Lomn | Talk 07:07, 15 July 2006 (UTC)
Also, [6] is a pretty extensive FAQ on MS's OEM operating systems. — Lomn | Talk 07:11, 15 July 2006 (UTC)
Thank you very much everyone. — QuantumEleven 08:38, 15 July 2006 (UTC)


Save more than 30 quid and a heck of a headache . . . run linux.

[edit] Moon dissappears?

If our Moon were to suddenly disappear, what would be the consequences for life or systems on Earth? I know things like tides would be affected, but would it be a disaster? Or would everything adapt well to the lack of the moon? I'm wondering if its effects on Earth and Earth's denizens is subtle or more essential...

http://www.google.com/search?q=if+we+had+no+moon --mboverload@ 10:55, 14 July 2006 (UTC)
I'm not sure but there are species of which the females use the moon to correct their biological calendar (menstruation cycle), the menstruate simultaneously then. Also, if there is no moon, it means that in certain parts of the world it will be pitch black every night, and I heard some creatures are urged by the full moon to reproduce. Oh well, I think some other people will know a lot more about this.--Evilbu 11:46, 14 July 2006 (UTC)
There is a whole lot of life that is dependent on the tide cycle; the Moon's disappearance would affect it in ways that would certainly be considered disastrous by some, although I don't suppose it would quite amount to a disaster for the world at large. But there are, thus, forms of life on Earth in whose lives the Moon plays a critical part. --Rallette 12:22, 14 July 2006 (UTC)
For one potential effect, check out the chaotic axial tilt theory in the Earth article. Axial tilt mentions we are headed towards that disaster anyway (though it'll take a while). --Weregerbil 12:47, 14 July 2006 (UTC)
That same question was asked a few years back to New Scientist's "Last Word". I don't remember the details of the answer but the going home message was that life as we know it would literally disappear. Life on earth is so deeply entagled with the presence of the moon that, apparently, a new ecosystem would have to be "rebuilt".--JLdesAlpins 20:50, 14 July 2006 (UTC)
IIRC, Isaac Asimov had an essay that addressed this very subject. Unfortunately, due to time and neuron loss, I'm unable to remember the title. A search might find it. In short, it would be a disaster. Bunthorne 02:29, 15 July 2006 (UTC)
Asimov wrote a pair of essays in the early 1970s entitled The Tragedy of the Moon, which argues that science was held back to a geocentric view of the universe by the moon very obviously orbiting Earth, and The Triumph of the Moon, which argues that intelligence and even land-based life may not have evolved without the Moon. The text of the latter appears to be here, but I don't know of its legitimacy. However, Asimov was discussing what may have happened if the Moon had never existed, not what might happen if it disappeared now.-gadfium 03:34, 15 July 2006 (UTC)

[edit] Brain size, body size and intelligence

I gather that the intelligence of a species varies according to the ratio of brain size to body size, rather than directly according to brain size (that being why elephants and whales have huge brains, but show no obvious signs of great intelligence). Why is this so? Would it not be more efficient for them to have a smaller, more efficient brain (somewhat like my own) and save the resources consumed by their huge brains for something more useful? HenryFlower 14:06, 14 July 2006 (UTC)

Brain to body mass ratio point out that all the extra brain mass "is required for housekeeping tasks, such as breathing, thermoregulation, senses, motor skill, etc." --Ginkgo100 talk · contribs · e@ 14:59, 14 July 2006 (UTC)

Thanks, but in that case I have another question. I'd always thought that the brain which allows us to be clever carries with it a significant cost in terms of the resources it requires. But the 'cleverness' (as opposed to housekeeping) part of the brain shouldn't need to be any larger for an elephant or a whale than it is for us. That implies that these larger animals could be significantly cleverer for a relatively small percentage increase in brain size. Is there just no advantage to them being cleverer? HenryFlower 18:04, 14 July 2006 (UTC)

It's not "no advantage", it "not enough additional advantage at the margin to make additional investment productive (when inertia is included)". --Tmh 20:02, 14 July 2006 (UTC)
Personally, I suspect that large brained animals have more detailed memories than we do. There is an evolutionary advantage to more memory, and not much disadvantage to having a large brain if you're an elephant or whale. On the other hand, humans can't afford to have that large of a brain, so have to compromise on memory. A shrew likely has almost no memory at all. By contrast, I don't think intelligence takes up all that much space. Some reasonably intelligent animals, like cuttlefish, have tiny brains. StuRat 22:25, 14 July 2006 (UTC)
Is this based on the aphorism that "an elephant never forgets"? Memory is testable. Has anyone tested the memories of large brained animals compared to the memory of humans? --Ginkgo100 talk · contribs · e@ 22:29, 14 July 2006 (UTC)
I'd be interested to see the results of such a study. One example of an elephant's memory is that they seem to recognize the skeletons of relatives that died many years ago. I assume this is because they recall where all their relatives died. Whales have songs that are quite long, this requires a fair bit of memory, too. StuRat 02:34, 15 July 2006 (UTC)
Many animals can run a lot faster than we can. Considering we've got a hunter/gatherer past, why don't we have the physique of a cheetah? Different animals use different methods to get an edge. Our edge is our intelligence. There is no one 'best solution'. Evolution is a constant search for a better design considerig the circumstances, but that doesn't mean a best design will ever be found. A large and active brain is costly in terms of energy. A cheetah may ruyn fast but is totally knackered and helpless after that. Every advantage has its disadvantage (a quote by Johan Cruyff that doesn't translate well into English). DirkvdM 09:39, 15 July 2006 (UTC)
Hmm, judging from your opinions I would have thought all quotes from the Dutch would be something like "America is the root of all evil in the world and the poor, misunderstood Muslims who blow up busloads of children are heroic freedom fighters who deserve our support." StuRat 15:09, 15 July 2006 (UTC)
We appear to have a serious communication problem. I'm not sure whether that has to do with brain size, body size or intelligence (yours or mine). Maybe we need a relation therapist. My God, we're we're behaving like a married couple. This is getting to be scary. DirkvdM 08:47, 16 July 2006 (UTC)

[edit] Switching voltage regulator

Typically, can you draw any current from a normal switching regulator (PT6214) if you put a load between the voltage source (24V) and the regulator output (12V)? --Jcmaco 14:47, 14 July 2006 (UTC)

It's unlikely that a buck converter can sink current from the output. This means that the current being drawn from the 12V output to ground must be greater than the current being carried from the 24V through your load to the 12V output. If this is the case, then you are basically providing additional output power through your load and the converter is making up the difference. If the current being drawn from the 12V output to ground is less than this additional current you are injecting into the output then the output voltage will rise above 12V. You could put a dummy load on the 12V to ensure regulation. Size the dummy load so that the converter always has to supply at least 100 mA. —Bradley 06:17, 15 July 2006 (UTC)

[edit] Displaced itch?

I'd like to know the name for the phenomenon where scratching an itch on one part of the body produces an itching sensation on a different part of the body, simultaneous with scratching. (Does anyone know what I mean?)

I once found something about it on the web, and a word for it. I think it was a German-sounding word, and I think that translated it meant something like displaced itch. But try as I might, I can't find anything about it anywhere anymore.

Any idea what it could be? Alf Boggis 16:44, 14 July 2006 (UTC)

Google for "referred itch" (with the quotes) and mitempfindung (or mitempfindungen), is that it? And if you have the time please write referred itch! Weregerbil 17:40, 15 July 2006 (UTC)
Yes, that's it! Thanks! Alf Boggis 08:24, 17 July 2006 (UTC)

[edit] High creatine level

What dose it mean if a blood test show high levels of Creatine and one has not been supplementing creatine? Anthony

First, click the "ask a new question by clicking here" at the top to ask a question. Then, your question won't be jammed up with the preceding one.
Did you read about how the body aquires creatine in the article on creatine? The liver could be producing a lot. Maybe the person just had a big steak or fish. Meat is a creatine supplement, so unless the person is a vegetarian, creatine is being supplemented. --Kainaw (talk) 19:19, 14 July 2006 (UTC)

Yes I know all about creatine how its made and what it dose, but is is a high (higher level).The average 155lbs. person has a total of about 120 grams of creatine in the body at any one time. Athletes use up more than 2 grams a day. But what if the level show up much higher and stay higher, and the person eats right, and is not taking creatine.They test for it so it most mean something. What? Anthony

This is what I've found sofar CREATINE KINASE, TOTAL TEST FOR MYOCARDIAL INFARCTION AND SKELETAL MUSCLE DAMAGE. ELEVATED RESULTS MAY BE DUE TO: MYOCARDITIS, MYOCARDIAL INFARCTION (HEART ATTACK), MUSCULAR DYSTROPHY, MUSCLE TRAUMA OR EXCESSIVE EXERCISE. (377SB=) CREATINE KINASE ISOENZYMES EVALUATION OF MYOCARDIAL INFARCTION What dose it mean if a blood test show high levels of creatine and one has not been supplementing creatine? Anthony

I suspect the question is really about creatinine rather than creatine as the former is measured perhaps 100,000 times more often than the latter. alteripse 21:11, 14 July 2006 (UTC)

Let me second that suspicion. Creatinine is measured just about every time your blood is drawn; creatine is not. (And creatine kinase would most likely appear in a lab report as CK or CPK). The three tests are different, so you must be certain which it is that is elevated. The person ordering the tests should be able to tell you about any abnormal lab values. The implications of an elevated creatinine level depend a bit on whether you have a normal or abnormal BUN level, normal or abnormal blood pressure, protein in the urine, etc., but the concern would be for kidney disease. Obviously you need your doctor to give you advice on whether your abnormal lab value needs further evaluation, and you should be asking him or her these questions! - Nunh-huh 23:43, 14 July 2006 (UTC)
I would tend to believe the spelling in the original question, and interpret the question as referring to creatine kinase, spelled out fully on a report (some labs do that), because: 1. It is repeated in what looks like a web search result, 2. There is talk of "taking creatine", which would place the questioner as a person probably familiar with "muscle building" routines (and risk of excess exercise), 3. The rephrasing of the question seems to indicate that the user does not distinguish between the enzyme and the substrate, 4. I consider it less likely that a high creatinine level would be obtained without the doctor explaining the implications to the patient (leading to the question being asked here), while a high CK could easily be dismissed as just an injection, described as unimportant, or not even mentioned to the patient (she sees it by chance on a report, maybe?), and 5. blood creatine is not a routine test, so that if the spelling was right, then the kinase part was probably inadvertently left out. If that is the situation, then the answer is that, in the absence of heart or brain injury, high levels of creatine (kinase) usually indicate skeletal muscle damage, the commonest causes probably probably being muscle bruising, intra-muscular injections, over-exercise and alcohol (the last as a cause for rhabdomyolysis, vs the lowered levels found in alcoholic liver disease). No specific order of incidence here, nor reference for "commonest" here, just a quick guess. So it's up to Anthony to refine his question. As it is stated it is somewhat open to conflicting "forensic-linguistic analysis" (and what would that activity be termed?) --Seejyb 11:49, 16 July 2006 (UTC)

Thanks Here is more info: Man blow out he's knee on the job, was sent to take a drug test, everything was clean, but they said he had high levels of creatine , they did not spell the word. I look it up in Quest Diagnostics web site that all I fond SKELETAL MUSCLE DAMAGE,MUSCLE TRAUMA OR EXCESSIVE EXERCISE. I call and said it was most likey because of he bad blown knee. ANTHONY

[edit] Sneezing spot

The sneezing page lists that besides nose irritation, bright lights can cause sneezes. This is well documented, but how about the sneezing spot, ie. the spot above the right eye, around the hairline or a bit over it, that, when scratched, also irritates a sneeze? --Tmh 20:00, 14 July 2006 (UTC)

I think you're the only one, mate. - Samsara (talk • contribs) 20:23, 14 July 2006 (UTC)
Crossed neurons, clearly. Find a neurophysiologist, write it up, and become famous! alteripse 23:37, 14 July 2006 (UTC)
Or just a conditioned response. Crazywolf 23:46, 14 July 2006 (UTC)
I haven't heard of that. --Proficient 01:31, 15 July 2006 (UTC)