Wikipedia:Reference desk/Archives/Science/2007 March 20

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March 20

Medical term needed

what is the equivalent Medical term for the tamil disease "Akki" —Preceding unsigned comment added by 122.164.132.63 (talk • contribs)

Herpes? [1] --David Iberri (talk) 01:52, 20 March 2007 (UTC)

(EC)This site claims that akki is Herpes simplex. -- MarcoTolo 01:54, 20 March 2007 (UTC)

Magnavox MWD2205 4 Head VCR/DVD Player Issues

I lost my manuel, and I am trying to find out if there is a tracking button on the player or the remote so that I can fix the tracking on a VHS tape. —The preceding unsigned comment was added by Andreagambler (talk • contribs) 03:28, 20 March 2007 (UTC).

• Owner's manual here; [2] --BenBurch 07:35, 20 March 2007 (UTC)

MONTREAL PROTOCOLS

By Who was the protocol developed ??

What are the major gudielines and how are they monitored ??

are there any consequences ?? —The preceding unsigned comment was added by 59.101.237.5 (talk) 10:07, 20 March 2007 (UTC).

Montreal Protocol. It is usually easier to check the article before posting here. —The preceding unsigned comment was added by 128.12.131.62 (talk) 10:27, 20 March 2007 (UTC).

Body colour changes due to diet

A while back I knew this person who had some sort of device with two metal prongs that they put in a glass of water. They claimed that it was silver and putting silver into the water. Also they claimed that if they drank too much they could turn grey. Sorry to be vage but thats all I have. Can anyone shed some light on this? I've heard they if humans drink too much carrot juce they'd turn orange but this really puzzeled me. Thanks! Think outside the box 12:19, 20 March 2007 (UTC)

That's not too vague. Both are true. Excess consumption of colloidal silver causes argyria. StuRat 12:40, 20 March 2007 (UTC)

Wow! I should warn them. Thanks for that StuRat Think outside the box 13:03, 20 March 2007 (UTC)

You're quite welcome. StuRat 00:45, 24 March 2007 (UTC)

We have a sugar + colourings + additives + orange juice drink called Sunny Delight in the UK. It was really popular amongst kids about ten years ago. I remember reading in the paper about a kid who turned orange after drinking pretty much nothing else but Sunny Delight. As for the colloidal silver, take a look at Stan Jones - probably the most notable grey/blue skinned man in the world. --Kurt Shaped Box 13:06, 20 March 2007 (UTC)

Too much carrot or carrot juice can result in an orangey tinge to the skin. It appears to be something that may occur, especially when a infant switches to solids. Do a google for orange skin or carotenemia Nil Einne 14:10, 20 March 2007 (UTC)

Carrots contain carotinoids, which are pigments, also responsible for autumn leaves and beetroots :) A lot of flamingo's food contains carotinoids, which is why they are pink :) If it works for them, it is likey to work with other animals too :) HS7 14:17, 20 March 2007 (UTC)

This isn't quite the same, but a lack of iron leads to paler skin :) HS7 14:32, 20 March 2007 (UTC)

We have Sunny Delight in the US too and everytime a girl drinks too much and becomes orange she gets a five second blurb on the news. [Mαc Δαvιs] (How's my driving?) ❖ 15:28, 20 March 2007 (UTC)

Hilariously, people here went through a phase of thinking that Sunny Delight was some sort of 'health drink'. There were a few stories in the press about it making kids' teeth fall out too... ;) --Kurt Shaped Box 16:02, 20 March 2007 (UTC)

That's the way they advertise it, sadly. Dump a bunch of corn syrup in, add 1% juice and dump seven packets of ascorbic acid into it and you have a 100% VITAMIN C SPORTS DRINK THAT'S COOL AND HEALTHY! -Wooty Woot? contribs 23:10, 20 March 2007 (UTC)

That's 'cause it is :) [Mαc Δαvιs] (How's my driving?) ❖ 18:15, 21 March 2007 (UTC)

CRO

how a cro can be used to measure L,C,and self capacitance of an inductor?

You'd really need a signal generator as well. Beyond that, all that's necessary is an impedance bridge and some simple linear algebra. -- mattb @ 2007-03-20T13:23Z

What is a cro? A raucous bird with its final consonant amputated? A (something) (something) oscillator? A cathode ray oscilloscope? Something that goes with Magnon? Edison 14:09, 20 March 2007 (UTC)

An oscilloscope could obviously measure the change in electric current over time (given a known source voltage and source resistance). This would allow you to calculate the L and R components of the inductor. (A square-wave or pulse generator might make this easier by allowing you to create a repetitive waveform.) For self-capacitance, I think you'll need to identify the resonant frequency and this means the use of an appropriate signal generator. Presumably, this is a homework question so I'll leave it to you to work out the details of test-circuit arrangement and mathematics.

Atlant 15:58, 20 March 2007 (UTC)

Yeah, you could manage without a signal generator, perhaps by generating a step function of sorts with a good switch ('twould need to have nearly no contact bounce). Even so, methinks this is less precise than methods using a signal generator. -- mattb @ 2007-03-20T21:50Z

I assume you want to measure separately, some inductance, some capacitance, and then the self capacitance of an inductor. There are some equations to help on this:

e = L di/dt

i = C dv/dt

f= 1/(2pi* sqrt LC)

So if you applied aknown di/dt to an inductor and measured the voltage, you could find the inductance.

Also, if you provided a steady current to a capacitor and measured its dv/dt you could calculate its caopacitance.

The third is a little more tricky, becuyase you have all 3 elements in the equivalent cct. Inductance, capacitance and resistance. Agree with Atlant, you need to find the inductance and then the self resonant frequency. You can then calculate the self capacitance.

8-)) —The preceding unsigned comment was added by 88.109.124.137 (talk • contribs).

Well, thinking a bit about what mattb was saying, I guess I was presuming some sort of electrical "impulse" generator, even if it was only a switch connecting the voltage source. A storage 'scope would be handy, allowing the observation of single-shot events. Otherwise, some sort of relaxation oscillator would be useful so you can have repetitive events. (In some old 'scopes, the horizontal trace signal was externally available and could be used!) Given an impulse, I guess you could evaluate the self-resonant frequency based on provoking ringing of the inductor; we used to test "flyback" transformers (television Horizontal output transformers) in that way. Then one could apply the various formulae.

Atlant 12:46, 21 March 2007 (UTC)

Yes, and I was (perhaps too presumptiously) assuming a scope with storage capabilities when I mentioned the single pulse measurement method. -- mattb @ 2007-03-23T02:45Z

Blonde Hair/Blondes

a quastion on genetics. Do pepole with blonde hair(real ones) have to posses other blonde facial hair : as eyebrows , beards and so on ? —The preceding unsigned comment was added by 82.81.145.66 (talk) 16:15, 20 March 2007 (UTC).

No. Body hair is often a different colour from head hair. Indeed, most natural blondes will have darker body hair. Rockpocket 17:23, 20 March 2007 (UTC)

Spelling note: Hair is blond, not "blonde". A blonde is a woman with blond hair. A man with blond hair is a blond (no "e"). --Trovatore 17:28, 20 March 2007 (UTC)

If anyone's curious, Blond#Etymology.2C_spelling.2C_and_grammar explains some of the spellings. -- Diletante 17:51, 20 March 2007 (UTC)

There is a illness in which a person has their whole body hairs white or blond. cant recall the name but i know its because they lack pigment in their bodys which if exposed to to much sunlight can cause some painful and sometimes deadly sideeffects. Maverick423 17:37, 20 March 2007 (UTC)

Albino. Clarityfiend 17:49, 20 March 2007 (UTC)

Interesting to hear that natural blond(e)s often have darker body hair, Rockpocket. It would be enlightening to know more about the genetics of that. For example, I know that while the genes that code for red hair on the head are generally recessive to everything other than blond hair, the linked gene(s?) for red 'Grown-up hair' appear to be dominant. How does the blond head/ dark body fit? Skittle 18:17, 20 March 2007 (UTC)

The answers to those questions aren't known, Skittle. The only gene that has a number of commonly found alleles that are strongly associated with human hair colour is the MC1R gene. Loss-of-function alleles are strongly associated with red hair. In most non-human mammals, MC1R is agonised (activated) by melanocortin hormones (proteins derived from pro-opiomelanocortin) to produce black/brown eumelanin pigments. An alternative agonist of MC1R is Agouti signalling peptide (ASP), when it binds to MC1R the protein "switches" the cascade to produce red/yellow phaeomelanin. So in non-human mammals, by controlling the production of ASP and melanocortins (either in a autocrine, paracrine or endocrine fashion), the animals can make yellow/red or black brown hair. You can see how spatial control of these proteins could result in different hair in different parts of the body. Infact, this mechanism is known to control the dark back/light belly colouration seen in many animals.

So, it was tempting for pigmentation biologists to hypothesize that the same type of system controlled variable pigmentation in humans. However, there proved to be a problem with this theory. Firstly blond hair in humans is actually a form of "light" eumelanin rather than phaeomelanin (which produces red hair in humans). Its not entirely clear why this type of eumelanin appears blond, but its thought that variation in the structure of the pigment-complex alters its pigmentary properties. But this is why both blondes and brunettes often tan well, while red-heads don't. Also, ASP doesn't appear to be involved in human pigmentation at all, instead human MC1R appears to have a level of endogenous activity which is ramped up on binding to melanocortins, but not "switched" by an alternative agonist. The production of phaeomelanin (red hair) in humans results on the reduction of the endogenous activity caused by loss-of-function mutations. So, the genetics of dark/blond hair are not known at the moment. Neither is the exact mechanism behind the difference in head hair/ body hair colour in humans, but there are clues. Its thought likely that paracrine hormone production is involved, since body hair production increases, darkens and thickens as we become sexually mature and body hair is almost always darker than head hair in blondes, never lighter.

I'll leave you with an interesting finding from the human MC1R red-hair studies: it was found that there was a corrolation between being a heterozygote ("carrier") for a loss-of-function MC1R allele and having gingerish facial and/or pubic hair, when head hair was not red. I, myself, have a "touch of red" when I grow a beard (I'll spare you the details of my pubes). So I genotyped myself and, true enough, I have one allele that is associated with red-hair and one that functions normally. Why this heterzyogote effect applies only to the body is unclear, but a similar genetic heterozygosity (in yet known genes) may account for differences in blondes also. But, moral of the story: if both you and your partner do not have red hair, but do have ginger pubes, then the chances of you having a red-hair child is significantly increased. End of public service announcement (with apologies for the length of this reply). Rockpocket 19:17, 20 March 2007 (UTC)

Thanks. That was a little beyond my biology, but I got the gist, and I think I'll have to reread, looking things up. Oh, and the last bit was sort of what I was refering to above. Skittle 20:45, 20 March 2007 (UTC)

Just to make sure u are talking about facial hair. it is clear to me that the blond color don't appear on the whole body hair , but mostly blond pepole also have blond eyebrows and blonde beards , I never saw a blonde (convining enough) that has black eyebrows so I'll repeat the quastion , does blonds always have blond eyebrows and other facial hair. btw the thank you for the spelling remark , the reason for the mistake I guess is the fact that I don't live in a country where English is the native language .

Its all depends on how you define the colour "blond". True, I have never seen a natural blonde with black eye brows or beards, but there are plenty with darker eyebrows and beards than their hair colour. A lot of blond men will have reddish beards also. My wife is a natural blonde and has what I would call "light brown" eyebrows (she doesn't have a beard). That said, her eyebrows do tend to turn more blond in colour when she has been exposed to the sun for a period of time. Rockpocket 20:27, 20 March 2007 (UTC)

No, I have very blond hair and my eyebrows are quite dark. In fact, the carpet matches the drapes. On top of that, my beard is reddish brown (russet?). − Twas Now ( talk • contribs • e-mail ) 05:06, 21 March 2007 (UTC)

There's quite a lengthy article in a recent edition of Science covering this very topic.

Atlant 12:54, 21 March 2007 (UTC)

Just to complicate things- I used to have blond hair, but it has been slowly turning brown for the last 18 years, and I still have very light coloured hair on my arms, legs and moustashe, whilst the rest of my hair is much darker :) HS7 19:22, 21 March 2007 (UTC)

Splitting Hairs

I have very thick wavy hair and have the constant problem of split ends. It seems that no matter what I do, I just have a whole bunch of them. Then it got me thinking: Is there a genetic benefit for humans to have this condition? And while we are at it, was there a genetic benefit to have straight hair whereas in Africa, to have curly hair? —The preceding unsigned comment was added by Juliet5935 (talk • contribs) 18:15, 20 March 2007 (UTC).

In early humans (long long time ago when we still followed the rules of selective reproduction) hair could play two roles. It could provide a benefit, such as providing warmth is cold regions or shielding from the sun in hot regions. Also, it may be used for sexual attraction. In modern times, pretty much all humans reproduce with no regard for genetic fitness, so it doesn't matter anymore. --Kainaw ^(talk) 19:34, 20 March 2007 (UTC)

Whoa, there. Saying that "pretty much all humans reproduce with no regard for genetic fitness, so it doesn't matter anymore" is simply not true. It is true that what made one fit in previous generations no longer does so today--nearsighted people don't get eaten by the nearest tiger--but as long as there are variations among people, some will be genetically "fitter" for their environment and more likely to leave more offspring. The environment may have changed, and the rules of selection may be different, but just because they don't follow your notion of fitness doesn't mean they don't exist. grendel|khan 15:19, 21 March 2007 (UTC)

I pointed out "genetic fitness". The two primary factors that correlate to the number of children per woman are financial means and education level. Those with the most poverty and least education have the most children. Those with the least poverty and most education have the least children. It is a stretch to claim that genes are a major factor in poverty and education. --Kainaw ^(talk) 16:29, 21 March 2007 (UTC)

To get back to the original question, I'd expect split ends to lead to "frizzy" hair, which might be better at keeping cool in hot climates. I would expect blonde frizzy hair to be prevalent in Africa, but blonde hair must have some other disadvantages, like making you easy to spot by predators and prey. I'm guessing that by the time blonde hair developed, people were mostly farmers and herders, not hunter-gatherers, so this issue was less important. Straight, dark hair that mats down is probably best for retaining heat in cold climates, like Eskimo hair. StuRat 21:37, 22 March 2007 (UTC)

This is pure speculation - there is no data to back it up, nor is it even a likely scenario.

For most people, split ends are simply the result of hair trauma. Asking if there is an evolutionary advantage in that situation is like asking whether there is an evolutionary advantage to having a broken arm.

Its entirely normal for the distal ends of long hair to be damaged because each particular shaft has has been washed, brushed, and manipulated literally thousands of times. According to David de Berker et al (Clinics in Dermatology, Volume 19, Issue 2 , March-April 2001, Pages 129-134) "it is normal for hair of 1 meter in length to have split ends and damaged cuticle. When the same changes are seen in hair of 20 mm, it either means that the hairs have been exposed to excessive heat and perming processes or that there is something intrinsically wrong with the hair". That said, if you have short hair, and have not exposed it to extreme conditions, then you may have a condition such trichothiodystrophy, trichorrhexis invaginata, pili torti, monilethrix, pseudomonilethrix... the list goes on. The cause of most of these conditions are either unknown or as a result of some keratin mutations. In the latter case your hair would be the least of your worries.

As for split ends leading to frizzy hair, leading to the ability to keep cool, leading to prevelence in Africa. Total nonsense. Frizzy hair, such as those found in Africans, has nothing to do with split ends whatsoever. The curliness of hair is determined by the basal area of the follicle, with the bending process linked to a lack of axial symmetry in the lower part of the hair bulb. (See Sebastien Thibaut et al, Biology of hair shape, International Journal of Dermatology, 2005, 44, (Suppl. 1), 2–3). Finally, the only data available of pigmentation and human evolution strongly suggests positive selection due to the solar protective qualities of black, curly hair and skin, over blonde straight hair and white skin. There was no mention in that paper of the selective pressures of lions prefering the taste of easy to catch white skin over black. So the bottom line is that we don't know what advantage curly hair might provide to our African friends, but we do know that it has enhanced solar protective qualities. The most parsimonious explanantion, based on what we do know, would be that this pressure was relaxed in more northern climes and therefore curly hair was lost by genetic drift, or by sexual selection against. Rockpocket 03:04, 23 March 2007 (UTC)

You seem to be confused between frizzy hair and curly hair, they are not the same thing at all. Frizzy hair is caused by split ends, while curly hair is caused by elliptical cross sections (versus circular cross sections for straight hair). It is quite common to have straight, frizzy hair. StuRat 05:08, 25 March 2007 (UTC)

Your sexual selection theory is pure speculation with no data to back it up. Mate selection will generally favor features which are advantageous in a particular environment, as any individual which selects mates based on features which are disadvantageous to survival will be less likely to pass on their genes. There is a notable exception, in the form of "health indicators", such as the male peacock's tail feathers. While having large tail feathers is not in itself helpful for the bird's survival, the ability to grow the feathers shows the bird must be otherwise healthy, so is a good choice for a mate. StuRat 14:22, 23 March 2007 (UTC)

Once again, you are speaking total nonsense. At least two notable experts in the field have proposed that very theory with regards to hair colour. Firstly Jonathan Rees (Professor of Dermatology at Edinburgh University) has suggested sexual selection as a mechanism based on a study of the number of red and blond haired woman represented in Renaissance art (when in reality the number of woman with hair that colour would be low in the population). His theory is discussed in detail in by Marion Roach in Roots of Desire: The Myth, Meaning and Sexual Power of Red Hair, Bloomsbury USA, 2005. [ISBN 1-58234-344-6]. Secondly, and more convincingly, Peter Frost (a Canadian anthropologist) presented evidence in European hair and eye color: A case of frequency-dependent sexual selection? (Evolution and Human bahviour, Volume 27, Issue 2, Pages 85-103, 2006) that there was an operational sex ratio (OSR) in early Europeans leading towards a male shortage. He concludes that such an "OSR imbalance would have increased the pressures of sexual selection on early European women, one possible outcome being an unusual complex of color traits: hair- and eye-color diversity". The only study (PMID 10733465) that has attempted to determine whether true Darwinian selection, as you propose above, played a role in hair/skin colour in Europeans found no evidence for such pressures. Your comments above demonstrate you clearly do not understand human evolutionary genetics at any level of sophistication, perhaps you should restrict yourself to providing directions to reliable sources on this subject, rather than misleading readers with woefully innacurate theories. Rockpocket 17:28, 23 March 2007 (UTC)

Your evidence is weak. The best evidence you can find is someone saying "one possible outcome being...", which is clearly just their own speculation. One wild speculation based on another is not fact, and you should not represent it as such. Furthermore, if you are so incapable of engaging in civil debate that you need to lie about what your opponent says in an attempt to win ("lions preferring the taste...") then you have no place on the Ref Desk or in Wikipedia. Also, if you want to be taken seriously, learn how to spell or at least how to use a spell-checker. StuRat 23:08, 23 March 2007 (UTC)

The evidence isn't particularly strong and I never said it was fact, instead I phrased it as "the most parsimonious explanantion, based on what we do know". This is a perfectly accurate description it, because there is evidence, published by experts in reliable journals (you could try reading the entire article rather than making judgements from a single quote). Their analysis is of value, because it is educated; yours is not. My comment about lions was an obviously tongue-in-cheek aside. If you didn't get the inference, let me rephrase: there is no published data suggesting "blonde hair must have some other disadvantages, like making you easy to spot by predators and prey". The Ref Desk is not the place for "civil debate," it is the place for providing direction to expert information. When you start providing that instead of wild theories without any basis in reality, I'll take advice from you. Rockpocket 02:29, 24 March 2007 (UTC)

Preferring the speculation of an "expert" over the speculation of everyone else is just an argument from authority. If there is no proof, there is no proof, regardless of who makes the claim. A scientist's guess is no better "evidence" than anyone else's guess. If there were any actual facts to support his speculation, I'm sure you would have mentioned them. Incidentally, you also need to work on your grammar, as "description it" is not a valid phrase. StuRat 13:17, 24 March 2007 (UTC)

good control theory book?

I'm looking for a good book on Control theory, particularly PID controllers and their tuning. (I know the basics about these subjects, but would like to know more.) Something nicely practical, not merely abstrusely theoretical. Anyone got any recommendations? --Steve Summit (talk) 18:17, 20 March 2007 (UTC)

I was going to suggest my Control Theory textbook from a few years ago. Then I realized I couldn't remember the title, or the author. I went to get it, and realized that I left it in the last state I was in. It probably wasn't such a good Control Theory book after all, I guess. However, I do remember from that class that there was a highly-experienced industrial roboticist who was working on his degree after some ten years in the field. His anecdote is that "in practice, you tune a PID by trial and error." I had formal theoretical training before practical experience, so I beg to differ, but there is still some merit to that approach. If it's practical-knowledge you want, you might look in to a book on mechatronics instead of control-theory - the overlap is significant, but the treatment tends to be much more practical. Nimur 17:55, 22 March 2007 (UTC)

swollen legs

Hi, my mum's lower extremities(legs) ve been swollen for the past 5days now and she claims the problem is from her heart,she said her heart is not pumping well,that's why her legs are swollen.But i dont get it,please how is the swollen effect connected to the heart? couldnt it be edema nor blood cloth?please i need some clarifications on this and also the cause of the problem.(Note- is not a medical advice,is just to clarify my curiosity.) thanks

For starters, you can read up on congestive heart failure and interstitial fluid. Anchoress 18:44, 20 March 2007 (UTC)

Of course, she should definitely see a doctor in any case (I'm assuming my writing that doesn't violate the medical advice rules). $\sim$ Lenoxus " * " 19:03, 20 March 2007 (UTC)

See Eclampsia - often due to high blood pressure. Pregnant women are particularly prone to this. It's quite dangerous. But "See A Doctor" is the only advice we're allowed to give. SteveBaker 20:27, 21 March 2007 (UTC)

The eclampsia article makes it sound like it's a pregnancy-only syndrome. Anchoress 01:13, 23 March 2007 (UTC)

• If your mum hasn't seen the doctor, she should. --BenBurch 02:06, 22 March 2007 (UTC)

Daily intake of nuts

I've seen this so many times but now that I'm looking I can't find it. What's the recommendation for daily intake of nuts for health? Is it a handful, 30g, what? Anchoress 18:51, 20 March 2007 (UTC)

I can't find a simple answer from the USDA... here is information for the total meat/nut/bean consumption, but not specifically nuts. Nimur 19:32, 20 March 2007 (UTC)

Thank you very much for that link; I will bookmark it for use with other projects. What I'm looking for is the advice on nuts only (not legumes or other proteins) with regards to the beneficial qualities of nuts' omegas, other good fats, and other micronutrients. Anchoress 19:54, 20 March 2007 (UTC)

I don't recall ever having seen a campaign for "nuts". Unfortunately these days, a lot of dietary information seems commercially driven: meat, milk, eggs they all have "foundation" seem to go on about "recommended portions" but the truth is, there isn't one single food group which can't be substituted out of a diet, which may very much be the case for nuts. I personally don't eat a lot of nuts and I bet a lot of people don't ever eat nuts, in fact, there are people who are fatally allergic to nuts. So my guess is, there simply is no accurate recommended daily intake of nuts, as long as you don't exceed any other intakes such as 'oil' or 'salt' or whatever else. Vespine 21:57, 20 March 2007 (UTC)

You can get more than the recommended daily intake of nuts here at the reference desks...or were you talking about those nuts? Clarityfiend 02:16, 21 March 2007 (UTC)

Yeah I know, I think I've already OD'd today. Anchoress 02:31, 21 March 2007 (UTC)

Here is a ref from 2001:[3] that says an ounce (30g) of buts five or more times a week reduces risk of coronary artery disease by 25 to 39% (assuming you aren't allergic, of course).Edison 13:47, 21 March 2007 (UTC)

Yeah, that's exactly the kind of thing I was looking for. Thank you!!! Anchoress 18:26, 21 March 2007 (UTC)

surely it would reduce the risk even if you were allergic :] HS7 19:19, 21 March 2007 (UTC)

Correct, if you die of anaphylactic shock, that substantially reduces your future risk of heart disease. StuRat 21:27, 22 March 2007 (UTC)

Also, of all the nuts, walnuts are the best as far as omega-3. I like them in oatmeal with brown sugar and raisins (or bananas). StuRat 21:27, 22 March 2007 (UTC)

blood type and sub antibodies

I have Leukemia CML type. I was given a card that states I am:

Blood Group O  RH positive
Antibodies: anti-K-1

It is the anti-K-1 part that I do not understand the significance of.)

I am hoping some one will be able to explain to me what the importance of the anti-K-1 antibodies means.

Thank You, LL —The preceding unsigned comment was added by 74.13.56.147 (talk) 19:01, 20 March 2007 (UTC).

This appears to be medical short-hand for the Kell antigen system. You should surely verify with your doctor. You might want to get a more general idea from our blood type article. Nimur 19:35, 20 March 2007 (UTC)

I think it is the Anti-Kell₁ antibody. See Hemolytic disease of the newborn (anti-Kell). It is normally in infants. --Kainaw ^(talk) 19:41, 20 March 2007 (UTC)

METAR report

I have a METAR report that ends in RMK 6AC140 NOSIG. What does the 6AC140 mean? Thanks.

Do you mean the weather-related METAR? If so, does the article offer any useful info? Anchoress 21:59, 20 March 2007 (UTC)

Look, that answer is really not helpful. I'm asking because the article does not provide me with the answer, and I've been unable to find the exact information online. If you can point me to some information which does, that would be appreciated. —The preceding unsigned comment was added by 129.78.64.102 (talk) 23:44, 20 March 2007 (UTC).

Well now that I know that you mean the METAR I linked to, and you did read the article, I do have more info I could point you to, but I don't expend energy assisting people who don't accept my good faith efforts to help them in the spirit in which they were given. Apologies in advance for being off-topic and snarky. Undoubtedly someone else will be able to find the info I found to answer your question. Anchoress 01:03, 21 March 2007 (UTC)

May I remind you of the large block of text at the top of the page which asks users to "search first". Asking me to do the same and then claiming to have the necessary information and simultaneously withholding it from me, punishes me for actually following procedure and is contrary to WP:AGF. Do as you wish.

You're right, that was rude of me, and I'm sorry. In my defense, I have a horrible headache and probably shouldn't be posting at all. Anchoress 03:31, 21 March 2007 (UTC)

No harm, no foul.

I agree with the original comments from Anchoress. As there are certainly more than one "METAR report" in the world, you should have specified that you meant the weather-related report, provided the link, and stated that it didn't answer your question. Just because we ask people to read the article first does not mean we can assume they have all done so. In fact, there are many who fail to do so, so it was quite reasonable of Anchoress to ask if you did, since you failed to volunteer that info on your own. StuRat 19:39, 22 March 2007 (UTC)

Thanks for that, Stu. Anchoress 05:23, 24 March 2007 (UTC)

If you are referring to the difference in METAR reporting in the US and everywhere else, the RMK (remark) section is inherently nonstandard, so saying that I want detail on a portion of the METAR remark section is not ambiguous.

Secondly, I am quite confident of your abilities in going to articles yourself. There is one and only one article relating to the keyword "METAR", and it deals solely with weather reporting. I fail to see how Anchoress or yourself could have confused this with something else.

Finally, if I follow correct procedure and the METAR article answered my question, then there would be no need for me to ask the question. It is not an unreasonable assumption that Anchoress at least take a cursory examination of the article to confirm whether it might answer the question (a simple search of the article would suffice) before suggesting I read it. If she would have done so, she would have come to the independent conclusion that the article wasn't helpful either. Do you understand how unhelpful it is referring me to an article that doesn't answer the question, when she could have checked ahead and saved us all the trouble?

Hi, user 129: Just to let you know, I did check the METAR article, but I didn't (at the time) know enough about the topic to know for certain that it didn't answer your question. And I asked if you had checked the article because, as StuRat stated, many (most) questioners on the RDs don't check the relevant articles before posting their ?s, and so it is the habit of most regular respondents to assume that - unless the ?er informs us otherwise - the ?er hasn't checked the article. In fact, many ?ers don't even know there are relevant articles on WP. And, because there are so many possible avenues of research to follow in answering your question, I just wanted to confirm what you had done yourself before pursuing any of them. Anyways, sorry for any upset or consternation my usual question answering MO has caused, and best wishes! Anchoress 05:23, 24 March 2007 (UTC)

I understand completely that some people "don't get it"; but it isn't that hard: if the keyword or part of the keyword that I was interested in wasn't present in the article, then the article is most likely not useful or helpful. There really wasn't any harm done in you asking, I just felt that the suggestion wasn't helpful. I didn't mean my original responses in an irritated fashion either, but I just wanted to make my points regarding your response clear.

To explain in more detail why we ask people if they have read the article and found the info there, consider it from the POV of efficiency. There is only one question asker, so it only takes X amount of time for them to read the relevant article(s) and report if they found the answer there. On the other hand, there may well be 10 responders, and 100 readers of the question. If each of those must independently read the relevant article(s) to confirm that they are not helpful, that will take 10X or 100X the effort, and for no good reason. If the original poster simply states that they read the relevant article(s) and didn't find the answer, the time of all those responders and potential responders can be better spent researching elsewhere. I understand that the implication that you aren't smart enough to read the relevant articles on your own may be insulting, just like when you call for computer support because you have a blank screen and they ask if the computer is plugged in. However, there are indeed people who call with unplugged computers, so they do have a legit reason to ask. Those of us smart enough to check such things on our own first just need to bear with them until they get past the "computers for dummies" part of their script. StuRat 16:29, 24 March 2007 (UTC)

The problem I have, StuRat, is that one should check whether the article is worth being referred to before referring it to others. Granted the respondent can't be expected to know everything about every article, but in this case, it wasn't extremely difficult to see whether the keyword in question was contained in the article.

What's the full METAR? I think there are some sites that can translate. Splintercellguy 00:02, 21 March 2007 (UTC)

Yes, but they do not necessarily translate everything, and its likely that not all remarks will be translated either. —The preceding unsigned comment was added by 129.78.64.102 (talk) 00:06, 21 March 2007 (UTC).

Hmm, I'm no expert, but googling "6AC140" yields METARs with similar string portion as yours. Splintercellguy 01:24, 21 March 2007 (UTC)

You don't get it. I want to know what 6AC140 translates to, not just METARS with that reported. For example, NOSIG in the above example means that no significant change is expected. What does 6AC140 mean? —The preceding unsigned comment was added by 129.78.64.102 (talk) 02:15, 21 March 2007 (UTC).

Okay, trying here. From this page, it has this line in the table for remarks:

6pppp - 6 hour precipitation in .01 inches

Perhaps this is what you want? I try to please :). Splintercellguy 04:20, 21 March 2007 (UTC)

Thanks, but I don't think that's it. The pppp signifies four similar characters, (eg VVVVSM is designates four characters for visibility plus an SM to denote statute miles) -- it's not very good syntax, but it's what they use. It still doesn't explain what the AC is and AC140 is five characters.

The only reference so far I can find to AC in METAR syntax is a reference to the could genus (ie alto cumulus). I'm still looking, though. --Cody.Pope 04:58, 21 March 2007 (UTC)

Thanks. I noticed that too, but it doesn't seem to fit.

Aight, I can't be totally sure, but is you look at this list of METARs and cross reference it with this list of cloud types, you'll notice that whenever a block of #XX### appears, as a remark, the XX matches to some type of cloud type. I can't tell you what the numbers mean, however. Hope that helps, it sure was interesting learning about METAR cause until right now, I knew NOTHING about it. So if you're about to fly a plane, don't trust what I just said (if I find more, I'll post it). --Cody.Pope 05:20, 21 March 2007 (UTC)

Actually, I think you're on to something. I think the last three characters are the flight level of the cloud. I still don't know what the first digit is for, though.

Ok, so if we buy the cloud type and flight level argument, you'll also notice that when multiple #₁XX#₂#₃#₄ blocks appear, #₁ of the first block is always smaller than #₁ of the next block -- so perhaps it's a distance in some-unit(?) till you encounter that cloud type along the flight path? --Cody.Pope 05:36, 21 March 2007 (UTC)

There could be multiple flight paths, could there not?

Ah yes, there could be. Some kind of directional marker? --Cody.Pope 06:12, 21 March 2007 (UTC)

6AC140 is very strange. AC is not in FAR/AIM handbook in METAR section. Could it be a plain language remark? I don't see AC as a weather code because it's too similiar to aircraft. That said, could it mean 6 aircraft 14,000 ft? I;ve never seen that in a METAR but it could indicate weather baloons or something related to the metar station. What was the METAR station that issued it and what was the full line? --Tbeatty 06:00, 21 March 2007 (UTC)

Perhaps, but I think we've narrowed down the XX portion as a cloud type, I've now found a bunch of METAR reports (from multiple locations) with the aforementioned patterns (ie #₁XX###, with #₁ increasing in each progressive block). --Cody.Pope 06:11, 21 March 2007 (UTC)

6 = Second lowest broken cloud layer. AC = altocumulus 140 = 14,000 ft. Closest I can find. Here is a good source. --Tbeatty 06:42, 21 March 2007 (UTC)

Yes, I thought that it may have been the cloud overage in oktas on the way home. Thanks to all!

Body heat - How's it done?

I'm curious as to the process by which warm-blooded animals actually create internal heat. I guess it's a chemical system of some kind but I'd like to know how it's done.Cuzzi 22:16, 20 March 2007 (UTC)

Read up on the process in the homeothermic article. Anchoress 22:24, 20 March 2007 (UTC)

You might also want to read up on the citric acid cycle and electron transport--VectorPotential^Talk 00:47, 21 March 2007 (UTC)

Thanks, folks. So - would the quick answer be that heat is a bi-product of the conversion of nutrients into energy?Cuzzi 01:18, 21 March 2007 (UTC)

Yeah. :-) That was going to be my answer but I thought you wanted something more detailed. Internal combustion engine. Anchoress 01:22, 21 March 2007 (UTC)

(EC) Well, "by-product" generally implies that something is an peripheral process, where as homeothermic (warm-blooded) metabolism depends on the elevated temperature to a large degree. If you said "body heat is a function of the conversion of nutrients into energy" you'd be pretty safe. -- MarcoTolo 01:25, 21 March 2007 (UTC)

One of the byproducts is carbon dioxide, amongst other things. For example.Vespine 04:09, 21 March 2007 (UTC)

I think the more important aspect, is that metabolism is the primary function, and that when the production of ATP(ie metabolism) stops, *that* is when you release heat by dissipating the energy built up by electron transport, that would otherwise be used to synthesize ATP--VectorPotential^Talk 21:40, 21 March 2007 (UTC) Thanks, folks - that was all very informative and enlightening :-)Cuzzi 11:30, 24 March 2007 (UTC)