Wikipedia:Reference desk/Archives/Science/2007 June 4

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June 4

Bug found in house

On three separate occasions recently I have killed a bug in the house. I would like to know what it is. I have reviewed books available in the local city library and have not been able to identify it and would appreciate any help in doing so and so find out about control measures. The creature is about 3 cm. long and an eighth in diameter. Its general colour is grey green and it has lighter pale yellow stripes running along its back. Its legs are at one end where it has noticeable eyes and two large antennae. It moves quite quickly. Any help or advice where to inquire further would be appreciated.

64.228.37.28 01:40, 4 June 2007 (UTC)tartan savage

It seems that this is a bug identification desk! Can you put up a picture? GB 06:56, 4 June 2007 (UTC)

Or at least tell us where in the world you are. --Anonymous, June 4, 22:23 (UTC).

Los Angeles cable landing station

It seems whenever I traceroute servers across the Pacific, for example in Japan or Australia, the packets are almost always routed through Los Angeles. Is that because there's an important cable landing point there? If so, where is it specifically, and do they give public tours for interested geeks? —Keenan Pepper 01:54, 4 June 2007 (UTC)

It's possible that your ISP goes through MAE-West or some similar internet backbone hub in Los Angeles. --Wirbelwindヴィルヴェルヴィント (talk) 04:51, 4 June 2007 (UTC)

When going to Australia the data would go via the southern-cross cable, which lands at Monterey Bay, or San Lui Obispo. I guess these are somewhere near Los Angeles. The big ISPs would have their main routers in the city rather than a cable landing station. There are six more landing points for cables going to Japan, spread along the US west coast. GB 06:54, 4 June 2007 (UTC)

For the record, neither Monterey nor San Luis Obispo is particularly close to Los Angeles. LA is at 34°03′N, 118°15′W, SLO is at 35°17′N, 120°40′W, and Monterey is at 36°36′N, 121°54′W. SLO is about 180 miles from LA, and Monterey is another 180 miles from there. --LarryMac | Talk 13:34, 4 June 2007 (UTC)

Okay, here's an example. When I traceroute vnet.cn (a popular Chinese site), I get this:

13  dcr1-as0-0.LosAngeles.savvis.net (204.70.192.117)  73.702 ms  74.835 ms  73.400 ms
14  * 208.172.44.2 (208.172.44.2)  77.881 ms  76.231 ms
15  202.97.51.61 (202.97.51.61)  282.940 ms  286.178 ms  285.422 ms

Now, 208.172.44.2 is obviously on this side of the ocean, and 202.97.51.61 is on the other side. Where is 208.172.44.2, and how do the bits get across the ocean to 202.97.51.61? —Keenan Pepper 20:41, 4 June 2007 (UTC)

Magic, of course! And 202.97.51.61 is actually Asia Pacific Network Information Centre in Beijing, China, with a PO Box mailing address in Australia. The 208.172.44.2 is registered to Savvis located in Los Angeles, CA, and mailing address in Cary, NC. --Wirbelwindヴィルヴェルヴィント (talk) 21:37, 4 June 2007 (UTC)

Our article on submarine communications cables has a number of useful external links to maps (including this PDF) showing cable landing points around the world. I couldn't tell you which one your particular packets are flowing through. TenOfAllTrades(talk) 13:52, 5 June 2007 (UTC)

Multi-coloured hair

What is the most likely cause for a person having multiple hair colours? Some genetic mutation during development? Is there any particular name for this? -- Consumed Crustacean (talk) 06:03, 4 June 2007 (UTC)

The most common reason is hair dye. Hair dressers can dye hair in different patterns, and as the natural colour grows out the roots change back their colour. I used to have brown and blond hair at the same time naturally (Long ago when I had hair), but that was due to sun bleaching. GB 06:49, 4 June 2007 (UTC)

There are some links in Heterochromia. Best regards, Dr_Dima.

The most likely cause is age. My hair is brown and grey. (The simplest answers are always the best!) SteveBaker 13:15, 4 June 2007 (UTC)

Human chimeras, though rare, do exist and can have varied hair color. This is also (more-or-less) the mechanism by which calico cats manage to have three hair colors in one cat.

Atlant 13:44, 4 June 2007 (UTC)

This question may also be about naturally occuring hair color. When a person bleaches or dyes their hair, it looks fake because it is all one color. Natural hair is multi-colored. For example, my hair is black, dark brown, light brown, and nearly blond. Overall, it looks brown. But, strand by strand, it is multi-colored. --Kainaw ^(talk) 15:40, 4 June 2007 (UTC)

I think I understand what you are saying. I myself have different colored hair. The hair on my head is an unremarkable brown, while the hair on my Face is distinctly red. Also when I was a toddler, my hair was light blond and curly. While these Google articles refer mainly to hair color patterns in animal breeds, the gentic principles would be applicable to humans. -Czmtzc 17:57, 4 June 2007 (UTC)

The most likely reason you have red facial hair but brown head hair is because you are heterozygous for a MC1R mutant allele. There is a strong genetic correlation between these (I too have that combination, and I genotyped myself to check!). Apart from different hair colours in different parts of the body, human hairs tend to be relatively homogeneous in colour. This is different in non-human animals, because they have the ability to alter the pigment that is "injected" into the hair as it grows. Infact, many animal hairs are banded, with two different tones along the hair shaft. This is known as the "agouti" pattern (named after the eponymous rodent). The agouti gene controls this banding and, depending on when the gene is expressed both temporally and spatially, you can generate all sorts of cool colour patterns. Humans do not have an agouti gene, and therefore lost this trick sometime during their evolution. There are plenty of other genes that cause different hair colours though. Piebaldism, caused by mutation is genes that control the migration, replication or differentiation of melanocytes from the neural crest during embryogenesis, results in white spotting. These genes include Kit, Pax3 and Microphthalmia. See here for some examples of the genetic mouse mutants that have been created or discovered with crazy pigmentation. Rockpocket 01:31, 5 June 2007 (UTC)

A somatic mutation in the scalp may give someone a silver streak in their hair. Bendž|Ť 18:11, 4 June 2007 (UTC)

Lots of people have multi color hair. In fact the famous ex-PM of Japan have multi color hair. He has two colors.

1 Black hair

2 White hair

202.168.50.40 23:17, 4 June 2007 (UTC)

DNP + fat loss

I've been reading a lot about this lately, and even saw it on wikipedia, but im wondering if its really safe. I know you sweat like hell, makes your hot and all that, and I read about cataract reports, dehydration, and all that, but other than that, is it really unsafe?

Also found some info here: http://forums.steroid.com/showthread.php?t=145408&highlight=2%2C4-dinitrophenol

Its a steroid website, but DNP is not a steroid, I just ran into that site with a google search and it had the most info.

Since DNP reduces the mitochondrial function (works in a similar way to thermogenin) it could well be described as a poison. If you get the dose wrong the mitochondria may well not function enough for a person to perform normal activities (i.e. will not produce enough ATP). What is the right dose? Presumably its different for everyone? Given the uncertainties it does not sound like a healthy way to lose fat, not to mention it is banned by the FDA (Don't have ref on hand). David D. (Talk) 08:24, 4 June 2007 (UTC)

Note: thermogenin is only present in fat cells whereas DNP will function in all cells. Just because the uncoupling function (via thermogenin) is known as a normal process in fat cells it does not make DNP safe. David D. (Talk) 08:31, 4 June 2007 (UTC)

A quick search comes up witht he following health warning from Sonoma county.http://www.sonoma-county.org/da/DNP_alert.htm

"The young man's death was reported to the State Health Department by the Long Island Poison Control Center, which indicated that the individual apparently ingested 600 milligrams of DNP a day for four days."

"According to the Agency for Toxic Substances and Disease Registry, it was sold in the 1930's in diet pills but was banned in 1938 because of severe health effects. Dinitrophenols are toxic to the liver, kidney and nervous system. The chemical causes hyperthermia (increased body temperature), dehydration, tachycardia (rapid heartbeat), restlessness and manic behavior and convulsions which typically signify an immediate lift-threatening intoxication."

"Although DNP use in diet pills was banned in 1938, it is currently being marketed and used by body builders, and is also advertised and marketed on the Internet. The extent of its use is unknown at this time."

Hope thgis gives you an idea of the dangers involved by using DNP as a quick fix for weight loss. David D. (Talk) 18:32, 4 June 2007 (UTC)

I read all of that, but lets say if someone were to only use it for a week lets say. Not in huge amounts, not like the 600mg someone mentioned, and were to stay cool and drink lots and lots of water. Its funny that you mention rapid heartbeat, because most users use ECA (ephedra, caffeine, aspirin) with it to give them energy, and it would seem if the DNP already gave you a rapid heartbeat it would be just too much, so I think thats a rare side effect. I read thats its both liver and kidney friendly, and based on many many users, ive never heard of any kidney or liver problems.

What I was really wondering, as David mentioned above, that it reduces mitochondrial function, so if it doesn't reduce it too much, does it mean the drug is somewhat safe? And is raising the body temperature a degree or two very dangerous? I heard you can get a seizure from a pharmacist if you raise the body temperature, but I never heard of this happening in users from reading user logs. I also noticed if it was banned by the FDA, but if taken in short intervals, I don't think the liver/kidney problems, if any are an issue and I don't really think that the FDA thinks that sweating like crazy nonstop is an acceptable side effect, and that may be another reason that its banned, but if someone can deal with it on the short term, is this drug really that dangerous?

I also haven't read of any long term side effects in short DNP use, have you guys seen any? (Other than cataracts in long term use happening exclusively to women) —Preceding unsigned comment added by 76.167.136.84 (talk • contribs)

Why would anyone risk taking a chemical that makes their membranes leaky to protons (hydrogen ions)? This chemical will affect all cells, not just the fat cells. I suspect that the FDA thinks it is an unacceptable risk to be shutting down the mitochondrial function in all cells. i doubt they worry about excessive sweating. Cyanide also works by killing mitochondrial function. Clearly this is an extreme, and irreversible, example but that is the type of toxin you are dealing with if DNP is taken in high quantities.

Speculation ALERT Since DNP uncoupling mitochondria is not as drastic as killing the function of complex IV (the target for cyanide), I assume the death would be slower if too much was taken. Clearly the doses used by body builders are less than the toxic levels, but I expect the FDA probably regards it as an unacceptable risk (too close to toxic levels), especially in a culture where many think more is better.

In summary, clearly it is not always lethal since body builders are using it. But getting the dose right will always be tricky and potentially dangerous. David D. (Talk) 21:21, 5 June 2007 (UTC)

Thyroid Function

Is there anyway one can increase thyroid function to normal levels after something has caused it to decrease? (something such as a medicine, dieting, etc)

There are medicinal ways to do it. See hypothyroid for more info. Dismas|^(talk) 16:46, 4 June 2007 (UTC)

The article only mentions thyroid replacement therapy with such medicines as Synthroid under medical supervision after T4 and TSH levels are tested to verify there is in fact low thyroid. Edison 22:57, 4 June 2007 (UTC)

Thats not what I am asking. Heres a little bit more explanation. Lets say someone has normal thyroid function, but wants to lose weight. So he or she goes out and takes cytomel (T3) or synthroid (T4) or a pill that has both. The thyroid will stop producing thyroid hormones because he/she is taking it in pills. Now after the person stops using the pills, the thyroid will slowly restart producing the hormones it does, but it will be slow and it will take some time for it to be functioning at normal levels. In this time, the person can gain all the weight he/she has lost. Is there anyway to jumpstart the thyroid into normal production levels right after discontinuance of the thyroid hormone pills. I read that this is possible with Human chorionic gonadotropin (hCG) or clomid, but I have never heard of anyone doing this and I am not sure if it works. So I am wondering if anyone knows anything about this, and if it works, how long it takes to work, etc... Thanks

The literal simple answer to your question is No. Your question and your ideas about the relationship between thyroid and weight might be based on some erroneous information. Following is a fuller explanation. Doctors discovered about a century ago that adults with severe thyroid failure usually gained weight, and had a slow metabolism and sedentary proclivity. When they were given thyroid extract they became more active, their metabolic rate rose, and they lost weight and it stayed off. There were no reliable tests of thyroid function for the first half of the century, so any adult complaining of weight gain and lack of energy was likely to be given a trial of thyroid extract. For many people it did not work. By the middle of the 20th century, it became possible to test for thyroid function at least crudely. To no one's surprise it turned out that people whose thyroid tests were low were much more likely to get measurable benefit from treatment and people whose thyroid tests were normal were more likely to have hyperthyroid side effects (like rapid heart rate) and minimal measurable benefit (even if they had some temporary, subjective, placebo benefit). It also became steadily clearer that weight regulation depended on far more complex hormone and signal systems than simply thyroid hormone levels. So intelligent, honest doctors who were trying to help but not harm their patients stopped prescribing extra thyroid hormone as a weight-loss pill to people with normal thyroid function. If it worked and was safe, over half the adults you know would be taking it. It doesn't and it isn't. alteripse 19:52, 5 June 2007 (UTC)

Wait, lets backup one second. I am not trying to flame anyone, but telling me that my ideas between the relationship and the thyroid are incorrect is ridiculous. I never said self treatment using any thyroid hormone is "safe," never ever did I say that, nor did I say it was smart. If it was safe than we would not have overweight or obese people. But lets get something very very strait here. It does work, and if you think for one second that it does not, I think you need to do a little bit of research before you tell other people that you know more than them, and tell other people that what they know and what you don't know is erraneous information. As much as I appreciate your time and your response, I do not appreciate the words coming out of your mouth. If you do the least amount of research, I mean just a 5 second search in google, you will come up with a countless number of sources, forums, boards, where people, especially bodybuilders, have used thyroid hormones to shed weight quickly and effectively, notice I never said "safely," I said quickly and effectively. It might not be safe, or smart, but it sure does work, and that is someone you cannot argue against. And once again, my original question has not been answered.

Sorry to give offense, but you are doubly incorrect. Your original question was indeed answered; you just don't like the answer. As for the rest of your ideas, rather than say "countless sources", why don't you offer us a single source, just one, that contains strong evidence that use of extra thyroid hormone by overweight but not hypothyroid people can cause sustained weight loss? I know of no such evidence and would be indebted to you for the education. Put your source where your mouth is, please. alteripse 21:04, 5 June 2007 (UTC)

Wait a minute, if this is a disagreement over "safe", I bow out. There are a hundred destructive things people can do to lose weight and I will not engage in discussion of stupidity but will defer to the experts. alteripse 21:08, 5 June 2007 (UTC)

life of plastics

What are the factors that govern or extrapolate life of plastics?

1. The kind of plastic (acrylic glass lasts a lot longer than cellulose).
2. The environment (most plastics wouldn't last too long in the center of the sun).
3. What you mean by "life" (Does it have to look shiny and new? Does it have to hold its shape? Or does it only have to be detectable?) —Keenan Pepper 20:27, 4 June 2007 (UTC)

Indigenous peoples of the Americas

Is there any link which describes the different physical features of the Indigenous peoples of the Americas? Especially those who are from Alaska and those who are from Peru.

I normally see them broken into three groups: The Aztec/Inca/Mayan group. There are many theories about where they came from. I don't know what the latest accepted theory is. Then, there is the first wave of Asians that came over and populated North America. Finally, there are the current Inuits that came over from Asia also. That is a terrible over-simplication, but you can see how the North American/Inuit people are related as coming over from Asia. As for differences in appearance, the assumption is that they came from Asia. Look at the differences in appearance of the Asians. --Kainaw ^(talk) 13:18, 5 June 2007 (UTC)

You may also want to read Clovis culture.

Atlant 15:56, 5 June 2007 (UTC)

Being fertile

I don't know if I am fertile or not? Now I have had wet dreams but everytime I masturbate I don't make semen. Could I not be fertile over not making semen while masturbating? Heegoop, 4 June 2007 (UTC).

If you have medical concerns, I suggest asking your doctor. Friday (talk) 19:20, 4 June 2007 (UTC)

Yes, don't be afraid to talk to your doctor. Also, the answer depends on how old your are. If you're in your early teens, it's probably normal. —Keenan Pepper 20:22, 4 June 2007 (UTC)

Do bear in mind that producing semen isn't what's important for fertility. It's producing sperm. You could produce copious amounts of semen but would still be infertile if you aren't producing any sperm. Of course if you're producing sperm not semen you'd have fertility problems as well but anyway as Keenan mentions depending on your age it might be perfectly normal and if you're concerned you should see a doctor. N.B. I presume you're male. If you're female and complaining about not producing semen, you really, really need to ask your parents or someother trust worthy adult about sex and human biology Nil Einne 17:26, 5 June 2007 (UTC)