Wikipedia:Reference desk archive/Science/2006 August 25

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[edit] what causes breathing related pain in shoulders, neck ?

Hello,

I know medical advice is not something the people on this board like to give, and I understand their concerns. However, I have already consulted a doctor and taken the prescribed medication, but I feel the real cause hasn't been dealt with, not even discovered actually. So what I would ask is just proposals for the cause that I can explore on my own.

Some time ago I woke up unusually early with a pain in my right shoulder that wouldn't go away, even when not moving. It made me nauseous and hurt more every time I inhaled. The pain didn't seem to be coming from a specific point, it was like it was "hanging around there". Eventually I got some more rest and the pain became tolerable when remaining very calm and inhaling bit by bit. For a few days on I still had pain in my chest, shoulder and neck. A possible reason could have been working a few hours with an open window at night.

The strange thing is I had exactly the same thing two years ago : very sharp pain in the same arm when waking up, making me nauseous...that stabilized after a few hours and then kept lingering around for a few days.


My doctor prescribed some stuff that I have taken, but specified no cause. I'm not looking forward to the next time, so I would really like to know more about this.

So I repeat my request  : suggestion that I can do inquiries about in trustworthy works. If not acceptable by this desk's rules, then I won't argue.

Evilbu 00:07, 25 August 2006 (UTC)

You should have asked your doctor. It could be delayed onset muscle soreness. You feel it only days after the offended muscle has been overexerted, which may make it hard to relate cause and effect. Or it can have been a passing cramp of some intercostal muscle, which can occasionally occur without discernible trigger. Test: is it only breathing in, or only breathing out, that causes discomfort? If both directions are painful, you can rule out the cramp theory. Another test is if there is a spot that is (more) painful when you stab it with a finger. --LambiamTalk 00:57, 25 August 2006 (UTC)
Hmm, it could be that when I had it in february 2004, I had been working with an open window for some evenings. When I had it this time, I slept with an open window in the aftermath of our heat wave, but it was actually rather cool. So it's hard to tell how soon effects pop up. Thing is, two days ago I opened a window for like ten minutes and started feeling very minor discomfort in the shoulder. Breathing in caused most pain, breathing out didn't really cause much pain. No, touching those place from the outside with a finger didn't hurt at all. Thanks! Evilbu 12:15, 25 August 2006 (UTC)

Reminder: If requesting medical, dental, or legal advice, please consider asking a doctor, dentist, or lawyer instead. With free advice, you get what you pay for. - Cybergoth 04:52, 26 August 2006 (UTC)

[edit] Variable freezing in identical solutions

I've been doing some molecular biology this week and twice i have noticed an interesting discrepancy that i can't explain. I had placed 4 tubes containing completed PCR reactions in a regular -20C freezer, for about 72 hours. They were in the centre of the feezer, where the temp was (i later checked) as it should be. When i went to remove them i noticed three were frozen but one remained in the liquid state. Now, all of these should contain exactly the same concentration of salts, DNA, enzymes and glycerol. I can think of no obvious reason why one did not freeze while the others did. Puzzled, i went through some of my other freezer boxes to see if i could find another example. I did - one liquid tube containing just DNA this time, in a rack of eight, way at the back of the freezer. They had been there for months.

Just in case i had somehow messed up the reaction in the tube by adding the wrong thing, i ran my PCR reactions on a gel. The liquid sample had a nice amplicon, just the same as the others. So... my question: does anyone find this happen to them or have any idea what the hell was going on? Rockpocket 00:11, 25 August 2006 (UTC)

Supercooling? Maybe the tubes and fluids in the recalcitrant cases had no impurities to serve as seed for the crystallization. --LambiamTalk 00:42, August 25, 2006 (UTC)
Thanks. I guess that is the most likely mechanism. These are far from pure water solutions, however, and it just seems a bit odd to me that none of the crap in there would be sufficient to act as a seed for nucleation. And the liquid sample must have had the same reagents in there or else the reaction would not have proceeded. Rockpocket 00:54, 25 August 2006 (UTC)
I assume your lab is smart enough not to use a frost-free freezer. But, just in case they aren't, I should point out that the heating cycle used to melt the frost might very well thaw some of the contents, as well. Such a freezer dramatically shortens the life span of things stored within it, so should be replaced immediately. StuRat 01:03, 25 August 2006 (UTC)
I can attest that this is well known among biology labs. Most of the labs at my university (including my own) host periodic defrosting parties. Bring your own hammers, screwdrivers, and hair driers! Good times. – ClockworkSoul 04:11, 25 August 2006 (UTC)
Indeed. I've spent many a productive afternoon chipping away at that mammoth block of ice at the back of the freezer with screwdrivers. It isn't a frost free freezer. Rockpocket 04:19, 25 August 2006 (UTC)

[edit] Abdominal pain while running.

Yeah, it happens, while usually after I ate, but, even after a night's sleep, I can still wake up in the morning, not eat breakfast, and run at 6 a.m., and still have stomach pain. What can I do about it?

Is it because the stomach or intestines bounce too much when you run? And that the abdominal muscles do not strongly hold the organs compact? If so, could I do specific work outs, such as sit ups, to have stronger abdomen muscles and would that even help.

Usually I'm talking running a distance of a mile, but lately, I stopped weekly running when school finished so now it seems I will have stomach pain while only running 1/6th of a mile.. User:NealIRC 25 August 2006 1:22 (UTC)

I'm assuming it isn't a cramp of any kind. — [Mac Davis] (talk)
Nowadays the usual explanation is that it is a spasm of the diaphragm (anatomy) related to not using the proper technique of "belly breathing". See this page. --LambiamTalk 00:38, 25 August 2006 (UTC)

Heh no, no cramps here. Male. Thanks Lambiam, exactly what I am looking for. So what are some things I should prepare for right before I start running? Hyperventilate "a little" to prepare my lungs for some fast running? -User:NealIRC.

Spasms or cramps, same difference. Cramps are painful spasms. They visit males and females alike. No, what you should do is practise breathing techniques till belly breathing comes natural (and then not forget to maintain it while running). It has nothing to do with the lungs, it's the muscles. If you Google "breathing exercises" you'll find plenty of sites with (mostly) good advice. --LambiamTalk 01:35, 25 August 2006 (UTC)
Se our article, which discusses possible causes of the side stitch. -N·Blue talk 13:33, 25 August 2006 (UTC)

[edit] Increasing life expectancy

If life expectancy were increased to 250 years, then what might be the social and ecological consequences? How might we cope with them?--Patchouli 01:57, 25 August 2006 (UTC)

Would there be a corresponding decrease in mating periodicity, or should we expect that the adult humans reach breeding age at the same time as our normal life expectancy? Nimur 02:07, 25 August 2006 (UTC)
A social or ecological consequence? That's simple. World overpopulation. User:NealIRC 5:00, 25 August 2006 (UTC)
We already have that. That was caused (at least in part) by the decline of infant mortality. People used to have many kids to compensate. The need disappeared, but the habit of having ten kids didn't. Only in the last decades have people adapted, but only in the west. People living longer will, however, not have such an explosive/cumulative/exponential effect. People living twice as long will only double the population (provided people have the same amount of kids per person, not per timespan). The ecological consequences might, however, be more than double, because there are some cumulative effects (and feedback) there. In a social sense, the most needed adaption will probably be to accept that being 100 is not old. We have to adapt to that now, accepting that 65 is not a pensioning age. But this realisation will also only creep in. Luckily, unlike with the decision how many kids to have, there are people who make this sort of decision for others and they will (at least to some degree) think this through. So the negative effect should be much less than with decreased infant mortality. What we should really fear (ironically) is that poor countries will follow rich countries in this development. So should they really remain poor for their own good? Or will they learn from out mistakes? DirkvdM 11:16, 25 August 2006 (UTC)
I see two main possibilities. Either:
  1. an increase of 130 years is not an increase on good years so we'll basically have a large population of old and decrepid humans living out their retirement and being a burden on the state, their families, and wal-mart. Or
  2. slow social change. Think of all the prejudices associated with people living 100 years ago. The main reason we could have social change was because enough racists and sexists died off to give the more open-minded new generation a majority. So a society where people lived (and functioned) longer is one that would take much longer to end social injustice.
As far as overpopulation, the solution is the same without the life-extending treatments: get your ass to Mars. AEuSoes1 21:17, 25 August 2006 (UTC)
You may also want to read the spacer novels from Asimov. – b_jonas 21:27, 26 August 2006 (UTC)

[edit] Human ear on a mouse's back

Hi there - I'm trying to find out more information about the scientific event in the 1990's when scientists grafted a replica of a human ear on a mouse's back, the team was led by Dr Jay Vacanti. Can't find any articles relating to this event in Wikipedia.

Here's an image of the ear-mouse: http://www.bbc.co.uk/religion/ethics/animals/images/testing_earmouse.jpg

I don't see anything in Wikipedia on it. On the other hand, WP isn't the only source of info in the world, or even on the web:) Googling for Vacanti mouse finds a bunch of information that seems accessible to the general public. What specific info are you trying to find? DMacks 07:48, 25 August 2006 (UTC)
People should spend less time on the reference desk and more time putting information about the Vacanti mouse into wikipedia. --Username132 (talk) 16:19, 25 August 2006 (UTC)
Indeed. --Proficient 05:18, 29 August 2006 (UTC)

[edit] Planet

Can anyone explain to me the use of redefining the word planet thereby making Pluto a distant memory to those who won't learn what a dwarf planet is? The article definition of planet says that for most of the time there was no definition, while I thought it used to be "a heavenly body orbiting a sun which itself doesn't radiate any light". Thanks to the change, quiz cards, text books, encyclopedias and the like will have to be changed and old science fiction stories (Doctor Who, Star Trek, etc) will no doubt now contain errors as a result. All because Pluto's orbit isn't dominant. What exactly is the advantage the astronomers are getting from this definition. To me it looks like it creates more problems than it's solving. - Mgm|(talk) 07:27, 25 August 2006 (UTC)

So, what you're saying is that Doctor Who and Star Trek won't be scientifically accurate anymore? a few decades too late for that I think--71.249.31.135 12:27, 25 August 2006 (UTC)
If these "problems" increase the public's awareness of the ongoing nature of scientific inquiry into the Solar System, I say let's create more problems. Melchoir 07:36, 25 August 2006 (UTC)
It makes them aware, all right. Aware of the fact schools need to buy new books, that my Trivial Pursuit edition has yet another bunch of errors introduced. I bet that in a year's time most people will still answer 9 if you ask them about the number of planets in the solar system. - Mgm|(talk) 08:22, 25 August 2006 (UTC)
Science marches forward, and sometimes previously-accepted ideas need to be re-examined, modified, or wholely discarded when they are found to be insufficient or no-longer-workable. Also, science sometimes has very specific, hair-splitting definitions for terms that have broader or different meanings in conversational language. Well, progress progresses: there has to be a time "before" and a time "after" any such definition is written, or theory is accepted or discarded. I'm with Melchoir...people may as well learn that science involves rigorous definitions and progress can mean sacrificing even the sacredest of cows. Moo. DMacks
  • So why did the previous definition need modification? As far as I'm aware it worked fine. They could have left the definition in place and have subdivisions (instead of radically changing it). What wasn't working that this was needed according to the scientists involved? - Mgm|(talk) 08:17, 25 August 2006 (UTC)
    • The page that mentioned in your original question, definition of planet, explains some of the reasoning: there wasn't a real, formal definition; commonly-considered definitions seemed to include things that were even less planet-like than Pluto; discovery of "things orbiting stars other than ours" meant better descriptors of those things were needed. Patience might be good here...I'd expect that after the dust has settled, there will be some good explanations of the actual thinking instead of non-participants rationalizing a 20-hour-old news release:) DMacks 08:26, 25 August 2006 (UTC)
Also, this is far from the first time science has made textbooks, literature, and museums suddenly-incorrect. In elementary school I learned all about a dinosaur called a brontosaurus and science teachers taught that atoms were too small to ever be visualized individually. Heck, textbooks even taught me that Pluto was the most-distant of the (then-recognized:) planets, even though it had been closer than Neptune for several years at the time. DMacks 08:17, 25 August 2006 (UTC)
True, but that was because we found out things that disproved earlier findings. This planet thing claims "Pluto isn't a planet" because people decided to change the meaning of a word. Not because we found it wasn't actually a planet like in the examples you mention. - Mgm|(talk) 08:20, 25 August 2006 (UTC)
If I may respond down here to a point far above: schools buying new books... To construct a purposefully unsymphathetic example, let's say a school uses a textbook that says "there are 9 planets", and it presents this as some kind of God-given Fact. Let's say it doesn't explain the wide differences between planets, the historical mistakes and coincidences that led to the 9-planet picture, and the existence of the Kuiper belt which has been known for some time now. Then that school already needs to buy a new book, regardless of whatever the IAU says or does.
If, on the other extreme, a textbook is cognizant of these points, and it says "As of 200X, there are commonly considered to be 9 planets, but this is merely a social convention that has changed in the past and may change in the future", then the school does not need to replace their book, regardless of whatever the IAU says or does.
The IAU is quick to point out that their definition does not affect science. If a science textbook sticks to teaching science, then it is unaffected. If a science textbook is affected, that means there was something wrong with it already. Melchoir 09:33, 25 August 2006 (UTC)
I guess my real point is this: the IAU cannot be blamed for a textbook's pre-existing failures. Rather, it should be credited with forcing the issue. Melchoir 09:46, 25 August 2006 (UTC)
I suppose that to astronomers it isn't a big deal. Nothing has changed to their actual knowledge, just a redefinition of a term. Everyone using the same term in the same way means easier communication, less confusion. It's the general public (and the media) that make a big deal of it. For the rest, I totally agree with Melchior. He is a wise man. DirkvdM 11:29, 25 August 2006 (UTC)
  • Mgm, the biggest factor is probably the discovery of 2003UB313 (nicknamed "Xena") in the outer solar system which is bigger than Pluto, and the expectation that there are probably at least several other objects (and possibly dozens) of comparable size lurking at the fringes of our solar system. It posed a conundrum of whether to call Pluto, 2003UB313 and all similar objects planets or to demote Pluto and hence keep the list of planets short and tidy. Dragons flight 16:13, 25 August 2006 (UTC)
    • I would've expanded the list, but keeping the list of planets in our solar system short and tidy is a reason. A bad one, but at least it has some logic behind it. - Mgm|(talk) 21:24, 25 August 2006 (UTC)
As a dwarf planet, I would assume Pluto could still be called a planet in an informal, non-technical sense. Everybody wins! Peter Grey 13:08, 25 August 2006 (UTC)
Good point. I wonder what I should answer in a Trivial Pursuit game if the question comes up... - Mgm|(talk) 21:24, 25 August 2006 (UTC)
Give an intelligent, full answer and hope that your friends aren't ignorant jerks? Melchoir 17:36, 27 August 2006 (UTC)
Another thing to consider is that Pluto was initially thought to be much more massive than it is today. So The whole scientific debate could go something like this:
"Aha! I have found the ninth planet."
"Okay, but it's not really as big as you think it is. Maybe we shouldn't call it a planet"
"Well there's no size definition of planet that would keep Pluto out."
"But it hasn't even cleared its orbit."
"Um... er... well..."
"And look, Xena is even bigger than Pluto."
"Now that's no way to talk about Lucy Lawless."
"Let's just vote on it."
"But think of the textbooks we'll have to update."
"You mean the ones that we had to update to include stupid dinky little 'planet?'"
"oh... yeah."

fini

AEuSoes1 21:29, 25 August 2006 (UTC)

Textbook industry wasn't what it is today in 1930. Less updating. --Fastfission 02:56, 26 August 2006 (UTC)
As far as I'm concerned, Pluto will always be a planet in my heart. Poor lil' guy. First they name him after the god of the underworld, now they're saying he's just a dwarf. Ah well — at least they aren't changing the name of Plutonium to Dwarfonium or something like that. Personally I think the IAU should have had a second vote for whether Pluto would be considered "an honorary planet," which would have absolutely no scientific meaning. --Fastfission 02:56, 26 August 2006 (UTC)
I like the honorary planet suggestion. – b_jonas 21:22, 26 August 2006 (UTC)
We could go back to the original, classical definintion of a planet: an object that appears to move in the sky in relation to the stars. That puts Pluto back in, as well as restoring the Sun and Moon as planets, and makes the Earth not a planet. ... See, definitions change all the time — Michael J 13:55, 27 August 2006 (UTC)
Yes, Moon and Sun should be planets. I already recommended that at an other question here: #Planets... – b_jonas 21:32, 27 August 2006 (UTC)


People seem really interested in this Pluto. --Proficient 05:22, 29 August 2006 (UTC)

[edit] Biotechnology vs Genetic engineering

Are biotechnology and Genetic Engineering same thing?If not what are their differences ? —Preceding unsigned comment added by 203.91.130.4 (talk • contribs)

[edit] Help me please.

I am from nepal.I want to study Genetic Engineering.I have already passed my Bachelors.But I can go to any length to do Genetic Engineering.I am even ready to repeat my Bachelor's.Though there are so many Biotechnology Colleges that offer Genetic engineering as subsidary subject.I want to study Genetic engineering as my major subject.Can you people help me by giving names and address of some colleges from USA,UK,INDIA where I can study Genetic engineering—Preceding unsigned comment added by 203.91.130.4 (talk • contribs)

  • I'm not sure I can think of anywhere that you could select genetic engineering as a major, too specific for undergrad, and not specific enough for grad school. Have you taken many biology related courses before? or would you be starting a completly new field?--71.249.31.135 12:37, 25 August 2006 (UTC)
  • Oh nevermind, one of your older posts said you studied microbiology, which answers the later question--71.249.31.135 12:39, 25 August 2006 (UTC)
Massachusetts Institute of Technology has a good Biological Engineering department, which is largely "genetic engineering". Good luck --bmk
Also, the State University of New York at Stony Brook - my own alma mater - has a highly regarded biomedical engineering department and graduate program, within which is a genetic engineering emphasis (BME is just the umbrella program). – ClockworkSoul 16:07, 25 August 2006 (UTC)

[edit] NationalFSP

can any one explain this term to me "National FSP". its something related to U.S health care industry—Preceding unsigned comment added by 207.8.214.174 (talk • contribs)

  • You could start with FSP, from there, the only thing I can think of that would be federal would be the Food Stamp Program, run through the U.S. Department of Agriculture. But that doesn't really have to do with hleathcare. So, how about Facility Security Plan, that one came from google, also nothing to do with healthcare--71.249.31.135 12:34, 25 August 2006 (UTC)

[edit] Robby vs HAL

Which of these two would you consider more realistic:

  • Robby the Robot: The lumbering giant, straight out of the 1950s, complete with inelegant motion that make asimo look like a ballet dancer, stylized chrome cover, flashing lights, and a design so unnecessarily complex that it could only have come from 1950s scifi, and a simple Input/Output operating system.
  • The Heuristically programmed ALgorithmic computer, who is about as physically advanced as a Blade server, but has an AI that's far too overstated to ever really exist. On the other hand, he can play chess--71.249.31.135 14:09, 25 August 2006 (UTC)
"Realistic" could mean many things. HAL is unrealistic because the technology did not exist in 19981997. Robby is the product of Krell technology, so it can't be assessed by human standards. Peter Grey 15:58, 25 August 2006 (UTC) But based on appearances Robby did seem to lack the dexterity necessary for its duties. Peter Grey 18:22, 25 August 2006 (UTC)

[edit] Ear update

Ah, my ear. I vistied a general practicioner today. I got syringed (with a squirt bottle) by a nurse. I thought my hearing was fixed. Its not. It is much better, but still not like the left ear. It different not having any ear wax in my right ear. Goddamit. — [Mac Davis] (talk)

Shame, this place used to be a serious scientific reference desk. Please keep your arbituary conversations to the appropriate places. Philc TECI 15:57, 25 August 2006 (UTC)
Yeah, with the masturbating seagulls bagels, this place is a very serious scientific reference desk! — [Mac Davis] (talk)
Oh please no, we haven't had any seagull bagel related questions here in at least 2 transclusions, don't ruin it--152.163.100.74 18:58, 25 August 2006 (UTC)
Ruin it? The Reference desk would be ruined without seagulls. Hyenaste (tell) 16:11, 26 August 2006 (UTC)

I had to have my ears syringed, I live in the UK. The method used was that I had to put almond oil in each ear for 2 weeks to soften the wax. After the 2 weeks the nurse then gently and carefully used a kind of ear irrigation machine (not an old fashioned syringe). This removed most of the wax. I am very surprised that they used some kind of "squirt bottle" and that you didn't use some kind of oil for 2 weeks to soften the wax! The ear is a very delicate instrument and damage can be easily done, that is why such precautions SHOULD be taken. The fact that your hearing is still giving you problems is of some concern....is it the syringing they have just done causing you the problems now??

I'd like to say, if you had just ignored those silly warnings on the Q-tip box and used them to clean your ears out, this never would have gotten so bad that it required medical attention. StuRat 22:00, 25 August 2006 (UTC)
Somewhere in the world, a reference desk reader just stuck a Q-tip through his eardrum :) --bmk

Reminds me of a joke (true story?). A man walks into his doctor's office requesting a hearing aid. The doctor looks in his ears, and finds them full of wax, so he syringes them out. Three weeks later, the man returns. The doctor asks him, "how is your hearing?". He replies, "Great. I went home, but didn't tell anyone about the warwax. I've changed my will three times in the past week!". {paraphrased from "Stitches" magazine} - Cybergoth 05:03, 26 August 2006 (UTC)

Arbituary, Philc?? Great new word! Sounds like a death notice written for some member of the public chosen at random.  :--) JackofOz 04:20, 28 August 2006 (UTC)

[edit] Therapeutic Gene Modulation vs Gene Therapy

I created the therapeutic gene modulation page and wrote;

Therapeutic gene modulation refers the practice of altering expression of a gene at one of various stages, with a view to alleviate some form of ailment. It differs from gene therapy in that gene modulation seeks to alter the expression of an endogenous gene (perhaps through the introduction of a gene encoding a novel modulatory protein) whereas gene therapy concerns the introduction of a gene whose product aids the recipient directly.

-- would you agree that my synopsis is correct? --Username132 (talk) 16:16, 25 August 2006 (UTC)

I've writen something on the relevant talk page. Hopefully others visit there and it won't get lost as easily as it could here. --Seejyb 22:18, 25 August 2006 (UTC)

[edit] New Scientific Category

I intend to make two subcategories of the protein category, for novel proteins; proteins that have been designed and produced by the scientific community and naturally occuring proteins, since I feel the two should be distinguished. My question is what should the categories be entitled? Perhaps 'novel protein' and 'naturally occuring protein' or something similar? --Username132 (talk) 16:52, 25 August 2006 (UTC)

How about Category:Synthetic proteins and Category:Natural proteins? Just an idea; there might be something wrong with those adjectives. Melchoir 17:35, 25 August 2006 (UTC)
So you mean that the protein itself is newly designed, right? If that's not what you mean, I'd suggest 'recombinant proteins'; if that is what you mean, I'd suggest 'engineered proteins'. ike9898 20:52, 25 August 2006 (UTC)
  • It depends how they are made. I would go for "engineered proteins" and not make a difference between proteins made by recombinant techniques or organic chemistry. Make sure you discuss the idea with the relevant WikiProjects. They will probably have even better suggestions than we have. Mgm|(talk) 21:18, 25 August 2006 (UTC)
I attended a talk where the lecturer spoke about "designer proteins". The meaning was pretty clear to us. Google gets about 1000 hits for that phrase, and some respected references at that. But I see it was used in 1992 already, so maybe it has not caught on. I hope this helps you. --Seejyb 21:27, 25 August 2006 (UTC)

[edit] 9/11 Pentagon Attack help

Sir/Madem,

I m student from Royal Bhutan Institute of Technology, would like to ask few question regarding the structural resistance to pentagon attack as i have chosen the topic "Case study on structural behaviour of Pentagon towards plane crash" for my seminar presentation.

The questions are as follows: 1. What are the reasons that caused less damage on Pentagon even though the attack was huge? 2. Why column remaind unharmed where the densest and longest parts of a 757 would have penetrated whereas the column in other parts got failed where the attack was not that severe?

Your favour will be highly appreciated. Thank you, Ugyen Dorji

Isn't the Pentagon built from reinforced steel-concrete? And it is "The Pentagon"—an extremely important building that is near the heart of the United States's defense. Same reason. — [Mac Davis] (talk)
less damage on (the) Pentagon - less compared to what? column remaind unharmed where ... penetrated I'm skeptical if that is actually true, but if so, very likely because force would have been applied at a different angle and/or the failed column was designed differently and was actually weaker. Peter Grey 18:18, 25 August 2006 (UTC)

I'd say the main reason is that the Pentagon is short and wide, making it far more stable. Specifically, there was less weight from above bearing on the weakened portion of the structure and that weight could also be distributed to the remainder of the structure, which remained intact. StuRat 20:55, 25 August 2006 (UTC)

The pentagon was built very solidly with helical rebar arrangements in the columns, per a TV documentary. Edison 22:33, 25 August 2006 (UTC)

Simple (but incorrect) answer: The Pentagon was not struck by a plane. Rather, a cruise missile was used to cover up the fact that the USAF had recently fired upon, and shot down a civilian aircraft as part of an 'ends justify the means' policy.

Our articles American Airlines Flight 77 and The Pentagon have some information. --LambiamTalk 09:16, 26 August 2006 (UTC)
Aren't more crucial bits of the Pentagon deep underground? Or am I confusing it with something else? Maybe even some movie nonsense? DirkvdM 09:26, 26 August 2006 (UTC)
Yes, there are several stories underground, as well. You might also be thinking of Cheyenne Mountain, which is an impressive military base carved out of a mountain, and was shown in many movies, but, alas, is due to be mothballed. StuRat 09:34, 26 August 2006 (UTC)

[edit] Snake repelant

Hi I live on a farm and would like to know what I can use as a snke repellent as I have small children and pets. Please I need help urgently. Thank you

If you live on a working farm, you'll need the snakes more than the pets. Tell your kids not to bother the snakes and the snakes won't bother them. Problem solved. Matt Deres 20:13, 25 August 2006 (UTC) ps - why is this urgent?
The people still don't want to be bitten by the snakes, regardless of how useful they are for rodent control. StuRat 20:50, 25 August 2006 (UTC)
On Guam people eat snakes. I recieved several recipes I'm not going to try. — [Mac Davis] (talk) (Desk|Help me improve)
The only thing you can do is teach your kids how to react to snakes, and how to treat a bite. There is no way to repel them, they aren't insects. If you actively go out looking to kill them, you are likely to get bitten. Leaving them alone is the best option. As for pets, don't get hunting dogs, and hope. Where do you live, are there many dangerous snakes? --liquidGhoul 00:42, 26 August 2006 (UTC)

Get a mongoose ? :-) StuRat 08:57, 26 August 2006 (UTC)

...or a peafowl, or Austin Stevens... Seriously though, leave them alone and they will leave you alone. And don't let the gerbils out of your sight.--Shantavira 09:05, 26 August 2006 (UTC)
If you get Austin Stevens, you could get sued. He doesn't know how not to get bitten. --liquidGhoul 09:11, 26 August 2006 (UTC)
I just saw on "Dirty Jobs" that some snake controllers used naphthalene (mothballs) as repelent. — [Mac Davis] (talk) (Desk|Help me improve)

[edit] Duck's quack

Is it true that the duck's quack doesn't echo?

No. See Duck and Snopes.com. --Allen 17:53, 25 August 2006 (UTC)
Not true. Although, "Mythbusters" found the echo to actually be very difficult to find. There may be some exceptions, but I am not aware of any substance that completely absorbs sound if it is possible. — [Mac Davis] (talk)
There are substances which do better or worse jobs of absorbing sound, of course. The question is more about whether there are specific sounds which can be absorbed differently in the same substance, I'd imagine. --Fastfission 02:50, 26 August 2006 (UTC)
  • Give me one good reason for a sound not to echo. A duck's quack is no different than any other sound in the world. - Mgm|(talk) 21:15, 25 August 2006 (UTC)

It is most certainly different from all other sounds in the world. Edison 22:32, 25 August 2006 (UTC)

Do echos ever shift in frequency? If they did, one could imagine sounds very near to the edge of human hearing that would be hard to hear in an echo. But I don't see any of that on any of our echo-related pages so I imagine this isn't much of an issue. --Fastfission 02:50, 26 August 2006 (UTC)
If the echo is off a moving surface, yes, the frequency shifts. - Rainwarrior 04:22, 26 August 2006 (UTC)

I can imagine a sound "not making an echo" for a specific observer at a specific distance from a reflecting curved wall, with this distance being dependent on the frequency of the sound. At some point the peaks and troughs of the sound wave and it's reflection would cancel each other and you couldn't hear either. However, I see no reason why a duck quack would behave any differently in this respect. StuRat 09:29, 26 August 2006 (UTC)

The duck's quack has an echo, but of a certain type which dies away very quickly. They had to put it in a soundchamber to hear it. —Daniel (‽) 18:52, 26 August 2006 (UTC)

[edit] Reverse rotaion of earth

Is it possible to estimate the time remaining in the event when the earth's rotation about its axis will reversse and sun will rise from west?

Muhammad Hamza 17:58, 25 August 2006 (UTC)

time remaining until what? Time can be measured in lots of ways independent of the earth's rotation. Peter Grey 18:25, 25 August 2006 (UTC)
No it isn't possible, because Earth's rotation will never reverse. Currently, Earth's rotation is slowing down because the Moon's gravity is causing the Earth to slightly change shape (because the gravity affects the side of Earth closest to the Moon more, the opposite side less). But at the same time, this process is also causing the Moon to loose speed. Once the length of a day is exactly equal to the Moon's orbital period, the Moon won't move relative to any point on Earth, and therefore the Moon will not cause Earth to change shape. At this time, the length of a day will be fixed forever.
According to http://www.physlink.com/education/askexperts/ae695.cfm, it will be billions of years before Earth's rotation speed stops decreasing. When it does, Earth will take 47 current days to complete one rotation. The Sun would be gone by then, so nobody will be here to experience this event.
Well, that's the general idea, but I'm sure somebody can explain it better than I can. --Bowlhover 18:42, 25 August 2006 (UTC)
Approximately negative twenty-eight years. Melchoir 05:58, 27 August 2006 (UTC)
The tidal forces the Sun exerts on the Earth are causing its rotation to slow down. After a very long time (the billions of years suggested above is believeable) only one face of the Earth will be facing the Sun, just as only one face of the moon ever faces the Earth.

[edit] Earth's magnatic field

i heard from someone that the earth's magnetic field has reduced drastically in past few decades? can anyone confirm or refuse this fact by giving refernce? Muhammad Hamza 18:00, 25 August 2006 (UTC)

Have you checked Earth's magnetic field? –Mysid(t) 19:03, 25 August 2006 (UTC)
Yes, it has. References are in the article mentioned. We also had a discussion about polar reversals and excursions found above. — [Mac Davis] (talk)

[edit] Schizophrenics

what are the activities in which schizophrenics are more efficient than normal people? can anyone also refer to any psychology website which deals with all the braches of psychology and has articles for layman.

Have you found anything in the article on schizophrenia? A rather nice starting point for psychology information is the article on psychology; you can click on blue words, "main article" and "see also" material for additional information. Or just type suitable article titles to the Search box at the top left of this web page. Weregerbil 20:38, 25 August 2006 (UTC)
I don't think any. Disassociative thinking, impairments in the perception and/or expression of reality, delusions and auditory hallucinations, socially inept. I don't think those could be good for anything. — [Mac Davis] (talk)
President of the USA? Rockpocket 00:28, 26 August 2006 (UTC)
Nah. He's social, among the right society. --Fastfission 02:44, 26 August 2006 (UTC)
Are you perhaps thinking of autistic savants? Dragons flight 00:16, 26 August 2006 (UTC)
Anything you might gain from schizophrenia would probably be offset by the negative aspects. It is common for people to mythologize schizophrenia and to feel that "madness" and "genius" are very similar, but in most cases people with severe mental illness suffer horribly, even if other people think their work is "genius". --Fastfission 02:44, 26 August 2006 (UTC)

There are places where schizophrenics are considered enlightened. Madness and genius are not terms that can be used that easily anyway. Neither of them give a clear understanding of the situation. Both are relative to society and culture.

Maybe schizophrenics are more "normal" than the rest of humanity. Besides, schizophrenia can be controlled with medication in the majority of cases, and most sufferers lead "normal" lives. JackofOz 05:57, 29 August 2006 (UTC)

[edit] Red scrotum

For some reason lately I have been having a red scrotum, very wrinkly or bumpy it seems. I'm kinda worried I have testicular cancer, but I looked online and it doesn't seem that a very red scrotum is a symptom. But I'm still worried about what the cause of this might be and any help would be appreciated.

Reminder: If requesting medical, dental, or legal advice, please consider asking a doctor, dentist, or lawyer instead. Peter Grey 20:53, 25 August 2006 (UTC)
You need to go to the doctor man. Inflammation and swelling? If anything is ever wrong with your testicles, RUN. You don't want to lose them now do you? ;) — [Mac Davis] (talk)
see Jock itch.

Now this part of it has hardened, on the left testicle, the skin has hardened, and when I touch it it hurts. I think I may have epididymitis but I'm not sure but if I have testicular cancer then I'm not going to be able to handle it, I won't believe it!!!!!!!

The signs you describe are those of inflammation, of which cancer is not the most common cause. Try to force yourself to go see someone who can help no matter how shy or afraid you are. The chance are pretty good you'll be relieved of your worries. --Seejyb 08:50, 26 August 2006 (UTC)

Go to a doctor now. --Proficient 05:25, 29 August 2006 (UTC)

Also, though the article on Jock itch may be helpful, if it should match your symptoms, PLEASE don't use it as an excuse not to see a doctor. A far more helpful experience to think of would be that of John Kruk, the Phillies firstbaseman who actually had testicular cancer in one of his testicles. The article will probably ease your fears about the disease. Once diagnosed, the cancerous testicle was removed, but the other was just fine. You said that your pain is mainly on the left side, which can indicate that only one of them is affected. Testicles are like kidneys in this sense. All you need is one and you'll have all the same male sex hormones pumping through your body as if nothing had happened. Not one bit of your "manhood" will be lost. Of course I don't want to needlessly worry you, you most likely don't have testicular cancer at all, yet you must see a doctor as soon as possible, just to prevent the possibility of it spreading to the right. Having one testicle removed will not affect your life in the long run in any significant way. However having both removed is a different story. Good luck. Loomis 00:00, 1 September 2006 (UTC)

[edit] Frozen air

I just read A Pail of Air, an awesome short story about a family surviving after the Earth has been pulled away from the solar system by a passing brown dwarf. Most of the physics seemed completely plausible, but I have a couple of questions:

  • Wouldn't solid oxygen eat through a metal or wooden pail? How is liquid oxygen handled?
  • Doesn't solid nitrogen float on liquid oxygen, so the oxygen would end up buried beneath a thick layer of nitrogen? Or would they end up mixed together as frozen air? —Keenan Pepper 21:19, 25 August 2006 (UTC)
At a chemical plant it was a standard demo for visiting groups to put some liquid oxygen in an ordinary galvanized iron trash can. It did not eat through the metal. The point of the demo was to heat a piece of iron rebar red hot with a torch and thrust it into the liquid oxygen. The iron bar would burn violently as it was inserted in to the liquid oxygen, much as steel can be cut with an oxyacetylene torch after becomeing red hot just by the application of oxygen. On one spectacular instance, the guide accidentally touched the side of the trash can with the red hot iron bar. The entire trash can violently burned up. So the answer is liquid oxygen can be kept for a considerable period in an iron or steel can, as long as it does not get heated to the temperature of ignition. Edison 22:30, 25 August 2006 (UTC)
Liquid oxygen in small quantities is kept in glass "thermos" containers to keep it from evaporating - but it is not spectacularly reactive by itself. If you freeze a latex balloon you can keep a small amount of liquid oxygen in it. As to how it would settle out it would partially depend on how fast the temperature fell and how much wind was involved. Rmhermen 22:46, 25 August 2006 (UTC)
Oxygen doesnt have a point of ignition, it cannot burn. Philc TECI 02:06, 26 August 2006 (UTC)
Please reaqd the posting carefully: it is the IRON that burns! That is the whole point of HEATING THE END OF THE IRON BAR RED HOT! Edison 15:29, 26 August 2006 (UTC)
It is one of the reactants in an oxidation reaction, which is commonly called "burning". But, linguistically, people typically say something "burns in oxygen", as opposed to saying that the oxygen itself burns. It's a subtle distinction, however. StuRat 09:17, 26 August 2006 (UTC)

The thermoses would be dewar flasks. I don't see why O2(l) would "eat" through a bucket. — [Mac Davis] (talk)

I thought liquid oxygen was such a powerful oxidizing agent it would cause combustible things to ignite spontaneously. I guess you need a spark to start a liquid oxygen fire just like a regular fire, huh? Anyway, what about the second question? In the story, the frozen oxygen was on top of the frozen nitrogen. Why would that happen? —Keenan Pepper 23:11, 25 August 2006 (UTC)

I have no idea, and haven't read the piece either, but the freezing point of nitrogen is a bit higher than the freezing point of oxygen. Is it conceivable that when the mixture was cooled to a temperature between the two freezing points, and the nitrogen simply froze and sank in the liquid oxygen? Isopropyl 23:58, 25 August 2006 (UTC)
Oops. I guess I misread the question. I don't see why solid nitrogen would float on liquid oxygen; my guess is that it sinks? I have no clue. Isopropyl 00:04, 26 August 2006 (UTC)
Liquid oxygen is a good oxidising agent, but not that great, and by no means the best. liquid oxygen would be worse than gaseous oxygen, as any energy introduced would be initially used to boil the oxygen, before breaking the covalent bonds, and allowing the O ions to oxidize other chemicals. Philc TECI 02:12, 26 August 2006 (UTC)
Consider this: the condensed phase is about three orders of magnitude denser than the gas. This far outweighs having to evaporate the liquid. Dr Zak 05:00, 27 August 2006 (UTC)

Oh, this quote from Liquid Oxygen Barbecue Guy cleared things up for me: WARNING: an ignition source, such as a lit cigarette or one glowing coal, must be present before pouring on the LOX. If charcoal is PRESOAKED in LOX first, an explosion will result. One briquette presoaked in LOX is approx equiv to 1 stick of dynamite. —Keenan Pepper 23:17, 25 August 2006 (UTC)

Thats not quite true. Nothing soaked in LOX is equivalent to dynamite, though soaking dynamite in LOX may make it more explosive. You cannot compare them as LOX being an oxidising agent cannot burn, whereas thats all dynamite can do. The exolosive nature depends more on what it is oxidising. Philc TECI 02:15, 26 August 2006 (UTC)
...but ... but ...He's The LOX Barbecue Guy! — [Mac Davis] (talk) (Desk|Help me improve)
Our article on Oxyliquit suggests otherwise. Dr Zak 05:00, 27 August 2006 (UTC)

[edit] Speed Vac (centifugal concentrator)

I haven't used a Speed Vac (centifugal concentrator) in a really long time, so I can't tell if what I'm experiencing is normal. In a normal laboratory speed vac, if you put in two tubes, each with about 300 uL of aqueous solution, about how long would you expect the drying to take? What I'm really wondering is, if this takes 2 hours, does this indicate that it is not working right?? (this concentrator is equiped with a heating lamp, and I am using it) ike9898 21:21, 25 August 2006 (UTC)

Our speed vac drys at a rate of about 1uL per min (in the 10-50uL range) without heat (though it is ancient). Since yours appears to dry at twice this rate (albeit with heat), i would suggest that is not unreasonable. Rockpocket 22:29, 25 August 2006 (UTC)

[edit] Jumping Spider

dorsal
dorsal
ventral
ventral

We are trying to identify a jumping spider. It was found indoors in southern California. Its body was about 10mm long and 5 or 6mm wide (not counting legs). We were able to get some images using a light microscope. Our best guess so far is Phidippus audax or Phidippus workmani. Could anyone offer an expert opinion? See also here for a black and white full body image. Thanks. Rockpocket 23:08, 25 August 2006 (UTC)


[edit] Robinow Syndrome

Hello,

I am the granddaughter of Meinhard Robinow, discover of the Robinow Syndrome. I would like to add some information about Dr. Robinow himself. Please let me know if this is possible and how I may go about doing it(or if this is even the right place to make that request).

Thank You,

Jennifer K. Robinow

<email removed>

Simple. Make an account. Click this link: Meinhard Robinow. Write away! Help:Contents/Getting started will provide useful information & tools to get you started. You can also edit Robinow Syndrome. -- Scientizzle 23:24, 25 August 2006 (UTC)
However, please read Wikipedia:Autobiography and remember to cite published sources for the information you include. Personal experience isn't a good source because it's not verifiable. Anyway, happy editing! —Keenan Pepper 23:28, 25 August 2006 (UTC)
You can ask me if anytime arises in which you need any help with editing as well. I'm here except for the 8 hours in which I sleep. — [Mac Davis] (talk) (Desk|Help me improve)
You get 8 hours of sleep? Yeah, I was a beginner once too. – ClockworkSoul 04:25, 26 August 2006 (UTC)
Although sleep is the poor man's doctor, and is good to do when you are of stress, I actually wish I didn't have to sleep at all. It's like I'm missing out on life doing nothing. — [Mac Davis] (talk) (Desk|Help me improve)
Rethinking, I guess I get an average of ~6.5 hours. yay! — [Mac Davis] (talk) (Desk|Help me improve)
Jennifer, an explanation would be in order. 1. The <e-mail removed> above indicates that we (routinely) delete e-mail addresses in Wikipedia, since a large amount of spam would be visited upon the address once it gets harvested by the robots wandering the internet, and most users do not know or want that. 2. As suggested, to make things easier for yourself, get yourself a user account: If you look at the top of the page on the right, there is a link that says "Sign in/Create account". Click on that, fill in a few fields, and a few minutes later you can have a name and a discussion space (the most difficult would be finding a name which has not been taken yet!). The account creation does not require that you give any personal information, and it enables you to get personalised replies on what we call your "User page", as well as to be able to get ideas, ask questions and make suggestions more directly related to what you are trying to achieve. As an example, I still have a number of articles that your grandfather authored, relating to research we did on a family member with problems. At the time the 1995 "Appreciation" struck me as unusually noteworthy, since this was a tribute written while he was still alive, by well-known persons in medical genetics. So I would be interested in helping, but there are "everyday" personal facts about which a reader of scientific articles would have no clue. --Seejyb 10:54, 26 August 2006 (UTC)

[edit] biomeidcal model

hi! I can't find any information about the benefits and the limitation of biomedical model!Can you help to find some information about it! Thank you very much!

Elly.

Have you referred to Biomedical model? — [Mac Davis] (talk)