Wikipedia:Reference desk archive/Science/2006 June 25

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Insomnia side-effects[edit]

1. A few days ago I stopped drinking coffee and find that I am now unable to sleep for more than a few hours each night, and some nights I am unable to sleep at all. There is no associated anxiety or muscular tension. I feel physically fatigued, but can't seem to lose consciousness. When I used to drink coffee regularly, I slept at least six hours every night, though I often couldn't get to sleep until very late. Is this not the opposite of what should happen? I thought quitting coffee would leave me more tired.

2. Another question I've long asked myself... After a night without sleep, why does one's face tend to become oily? How does sleep prevent facial greasiness? And why does the face not produce such copious grease all day, but rather only when one ought to be sleeping? Why don't we wake up greasy?

Thanks! Bhumiya (said/done) 00:31, 25 June 2006 (UTC)

I cannot fully answer your questions, but I can provide some ideas. 1. Caffeine is a noncompetitive adenosine antagonist (if memory serves). Put roughly: adenosine is what makes you tired; caffeine decreases the effect of adenosine on neurons, and so one effect is to make you less tired. For this reason, one expects that a result of caffeine withdrawal would be fatigue. As someone who is not familiar with caffeine withdrawal on an academic level, your symptoms sort of surprise me, but sleep difficulties do often result when habitual medication or drug use changes, so even if I can't describe the exact process, it isn't really *that* surprising that you'd suffer from sleep disturbances. In any rate, the effect should go away fairly soon, I would imagine (but I am not a doctor!). 2. I know of no real reason, except that, if you sleep like I do, in the process of tossing and turning one's face will tend to contact one's pillowcase, which would have the effect of sort of dabbing your face clean over the course of the night. By not sleeping you just let the oil build up. Hope that helps... 65.96.221.107 01:04, 25 June 2006 (UTC)
  • Speaking as a coffee drinker, I'll just say this, start drinking coffee again, quiting just isn't worth it (:205.188.116.74 05:46, 25 June 2006 (UTC)
Caffeine notes that one effect of withdrawal is anxiety, and anxiety can definitely inhibit sleep. Caffeine withdrawal can be nasty, as I learned when I gave it up for Lent and experienced many of those symptoms. Fortunately it is over relatively quickly (no more than a week for me; one to five days according to the article). --Ginkgo100 talk · contribs 19:24, 25 June 2006 (UTC)
Try meditation. Helps me to sleep. I believe your body rests while meditating, even more recuperatively than deep sleep. Uh , I still drink coffee, but i feel no coffee effects(insomnia spells due to coffee, hyper feeling) when I meditate.--Jondel 06:02, 28 June 2006 (UTC)

Lightening in my eye[edit]

Remember how when you were a little kid you would always go around the house testing every 9 volt battery you could lay your tongue on? Well, I got very good at this, in fact, I could test the 1.5v AAA and AA batteries by pressing one terminal to the inside of my cheeck and the other terminal to my tounge. Well, one night I took the small, cylindrical 10v lithium battery out of my garage door opener and I 'tested' it using the same method. BAM! on the same side of my mouth which I tested it on, I saw huge streaks of lightening with that eye. It was pretty cool, so cool infact, I had my bro try it. About 2 hours later, both of our eyes ached. That was the one and only time I tried this. Tell me, what is causing my eye to see the lightening?

  • I'm confused, your garage door has a remote that needs a ten volt lithium ion battery? what?--205.188.116.74 05:44, 25 June 2006 (UTC)
http://en.wikipedia.org/wiki/Lithium_ion_battery It's commonplace for electronics. --Proficient 06:11, 25 June 2006 (UTC)
Lithium Ion Batteries are common place for electronics, but 10 volt baterries for a remote? less so, I'd think--205.188.116.74 07:30, 25 June 2006 (UTC)
Are you experiencing pain/dizziness when you see the lightning? --Proficient 06:11, 25 June 2006 (UTC)
Presumably your are depolarising the retinal cells or optic nerve on that side. One assumes that the discharge can cause uncoordinated contraction of the ocular muscles, which may cause the eye ache. An EEG and EMG may give a scientific answer, if you have a friendly neuro lab owner who is prepared to help you. --Seejyb 07:33, 25 June 2006 (UTC)
Li-ion batteries have a lot of charge in them, maybe the lightening was there, and it was arcing. Philc TECI 12:04, 25 June 2006 (UTC)

See phosphene. This question seems to come up a lot. - Cybergoth 00:56, 3 July 2006 (UTC)

How closely are seagulls and fulmars related?[edit]

Anyone know? I was told by someone today that a fulmar is not a seagull and is really a different species. I didn't believe him, so I looked up fulmars on Wikipedia. Is that article right?

If this is true, why does a fulmar look, sound, move and act like a seagull?

You would too if you saw how much booty seagulls get.  freshofftheufoΓΛĿЌ  06:00, 25 June 2006 (UTC)
They are a different order of bird. The have similarities because they fill similar niches. The birds of Australia are interesting to study in this respect. Their so-called robins and wrens, for example, resemble European robins and wrens, but they are completely unrelated. They fill equivalent niches by a process called convergent evolution.--Shantavira 08:40, 25 June 2006 (UTC)
One important question is begged at this point. Which one would win in a fight? :) --Kurt Shaped Box 19:30, 26 June 2006 (UTC)

Hissing soft drink[edit]

When I start to unscrew the cap of a bottle of soft drink and then stop (i.e., partially undo the cap), air hisses out, then the hissing subsides. If I loosen the cap a little more, the same thing happens again. Why does the air not all hiss out the first time? 220.253.90.98 01:57, 25 June 2006 (UTC)BenC

The cap continues to resist airflow for lower pressures. With the cap partially off, an equilibrium is reached at a level between the original pressure and the atmosphere, corresponding to the pressure difference that the partially unscrewed cap can resist. Peter Grey 02:40, 25 June 2006 (UTC)
Nice prose. --Proficient 06:12, 25 June 2006 (UTC)

History of AIDS epidemc in Dallas, Texas[edit]

When was the first case of AIDS reported in Dallas County, Texas? When did the first person die of AIDS in Dallas, Texas, and who was the first person to die of AIDS in Dallas, Texas? How many people have died of AIDS in Dallas County as of Jan. 1, 2006?

This is the best I could come out with. Though, it is three years out of date, but it should provide enough information about you questions. Iolakana|(talk) 14:46, 25 June 2006 (UTC)
The Texas Department of State Health Services may be able to help you. --Ginkgo100 talk · contribs 19:31, 25 June 2006 (UTC)


Thank you both for your help

Spider identification[edit]

I found this spider crawling across a book I was reading (Image:Unknown spider 1.JPG), and despite a lot of internet searching, I can not ID it. It kind of looks like a brown recluse spider, but without the violin shape on its back. The body was about 7 or 8 mm long. I live in the Chicago suburbs. I haven't seen any web. --Joelmills 02:38, 25 June 2006 (UTC)

It looks to me like a yellow sac spider: [1][2]. This page even says that they "resembles the brown recluse except that it is lighter in color and has no fiddle-shaped marking." --Fastfission 03:00, 25 June 2006 (UTC)

Thanks, that's definitely it. It looks just like the one on A.html this page. Glad it didn't bite me when I was trying to get it to pose. --Joelmills 03:18, 25 June 2006 (UTC)

It is quite normal if you did not find the beast on the internet, as it was in a book (today I'm busy putting emoticons :). --DLL 18:32, 25 June 2006 (UTC)

Officially Respected IQ Test[edit]

I have seen hundreds of different IQ tests; some require knowledge of historical facts plus basic knowledge of mathematics such as understanding permutations, combinations, and geometry.

Is there an official IQ test produced by an organization that is respected worldwide such as the United Nations University or Institute for Advanced Study?

I personally have come to the conclusion that this IQ matter is a hoax and basically a popular entertainment. Can someone give some guidance?Patchouli 06:52, 25 June 2006 (UTC)

Straight out of Harvard to the rescue: Perkins, David 1995, Outsmarting IQ, The Free Press, New York. --124.168.65.71 07:05, 25 June 2006 (UTC)

You can pay for a psychologist to give you a proper one. Thats about theonly legitimate way I know of. Philc TECI 12:00, 25 June 2006 (UTC)

The article IQ has some interesting insights, which suggests the "intelligence" part can be overplayed. "These tests measure a person's ability to conduct a number of tasks to which most people raised in that society will be exposed, and so measure a person's ability to absorb and repeat mechanical intellectual tasks.". This essentially is self-defining IQ as the ability to do well in IQ tests. Testing isn't about individual analysis; rather, it's a way to avoid dealing with individuals. The really useful thing about IQ tests is that it arranges people into an order, and on that basis quick decisions can be made without knowing the people. Some might argue that IQ tests simply measure what is easy to measure, rather than what is important, but that could be said of every test, and every measurement method in social science. See also IQ test controversy. Notinasnaid 12:21, 25 June 2006 (UTC)
  • I have often heard that "Intelligent Quotient scores are distributed normally with mean 100 and standard deviation 15." Thus, to obtain this famous IQ test that I don't know where to find and have never seen, do I need to pay a psychologist?Patchouli 13:59, 25 June 2006 (UTC)
I wouldn't trust any of the abundant free "IQ tests" on the Internet. There is no reason to believe any of them are standardized. When psychologists develop IQ tests, they take the distribution of scores (which for a good test is a normal distribution, a type of bell curve described by an equation) and "standardize" it. In other words, they make the mean raw score correspond to an IQ score of 100 and make all the others scores correspond to where they would fall on a normal distribution of standard deviation 15. See standard score for more information. So yes, if you want a standardized IQ test, talk to a psychologist. --Ginkgo100 talk · contribs 19:40, 25 June 2006 (UTC)
  • I just took one test that I was looking for at the International High IQ Society. I have become very confident that this IQ business is pure entertainment and fun. It is not like the Graduate Record Examination in Mathematics which I would never pass.

Patchouli 14:38, 25 June 2006 (UTC)

I've had similar experiences. I've taken online "IQ Tests" and generally scored no lower than 130, and as high as 165. I'm not saying this to brag, rather the opposite, these online "IQ Tests" seem to be more of a scam than the real thing, as they often encourage you to purchase a more detailed analysis of your score.
So what I've done is "tested" the tests themselves. Try it. Answer "C" to every question and see what score it gives you. A true IQ test should rate you as a moron with an IQ of no more than 50. If you get that, you'll be surer that you're dealing with a more legit test. However, if answering "C" to every question gives you an IQ of something like 110, you know you're dealing with a scam IQ test. Loomis 23:09, 25 June 2006 (UTC)
In my experience, the only accurate IQ test I ever took was for Mensa. Since they take IQ very seriously, it isn't a marketing scam with them. However, the best test I've ever taken for aptitude was the U.S. military ASVAB. It is free if you are under 35 and eligible to enlist. Of course, the recruiters will hound you for months afterward. --Kainaw (talk) 23:38, 25 June 2006 (UTC)
  • If I wanted to get in the U.S. military as a second lieutenant, would I have to take the ASVAB or a different test? I ask this because Patrick Tillman became a corporal whereas General Michael Hayden was granted the commission of a 2nd lieutenant at the commencement of service. Did they get different scores? Patchouli 02:31, 26 June 2006 (UTC)
    • My guess is ASVAB is only for enlisted personnel, not officers. Hayden got a comission effectively because he had a college degree and went to a ROTC. I think basically a college degree is what separates a future officer from a soldier. --Ornil 05:42, 26 June 2006 (UTC)
  • Patrick Tillman had a bachelor's degree in marketing.Patchouli 06:03, 26 June 2006 (UTC)
In the current U.S. military, a college degree (Bachelors or higher) is required to join as an officer. However, a person with a degree can enlist as an enlisted person (which Tillman did). Also, there is a warrant officer program that can allow an enlisted person to become an officer without a college degree - but every warrant officer I've met was working on a degree. As to why a person would opt to go enlisted when they could be an officer... it is a matter of choice. Some people feel that an officer who never was enlisted can never be as effective as one who knows what it is like to be enlisted. I served in the Marines and I remember a discussion that the Commandant of the Marine Corps is almost always an officer who began as an enlisted Marine. All in all, a college degree doesn't make a person in the military an officer. Also, the ASVAB score has nothing to do with becoming an officer. It is used to weed out idiots (if you can't pass the ASVAB, you are a danger to yourself and everyone around you) and help decide what job will be the best use of your potential. It is not the only test. I scored high on all sections of the ASVAB which led to two more tests in boot camp. One was computers/electronics and the other was languages. I failed the language test miserably, but did great on the computer/electronic test. So, I was sent off to computer/electronic school. I've always wished I was better at languages. I'd love to be able to communicate with anyone anywhere in the world. --Kainaw (talk) 14:33, 26 June 2006 (UTC)
  • There are many people who don't have any schooling but have considerable education. Is there any way for a person with no degree to either take a test and somehow demonstrate that he can become an officer?Patchouli 15:04, 26 June 2006 (UTC)
Yes. As I stated, you enlist and work your way toward the warrant officer program. Technically, you will be an officer while you are a warrant officer. When you finish, you will be a full officer. Keep in mind that most people see a Bachelor degree not as an education but as a finished long-term goal. It isn't something you can complete in one day with a quick test (except for the fake online degrees). That is why a 4-year degree is required so often. --Kainaw (talk) 19:27, 26 June 2006 (UTC)
Counterexample: Harry S Truman enlisted in the Missouri National Guard, was chosen to be an officer, and then commanded a regimental battery in France at the outset of World War I (1914-1918).Patchouli 05:40, 27 June 2006 (UTC)
I now remember that in 1800s, gentlemen used to buy their commission in England. (Source:Pride and Prejudice). I don't know the details of it in other country and will appreciate any information on any country on the planet.Patchouli 06:35, 27 June 2006 (UTC)

I'm not going to elaborate because of personal issues, but I have found that they vary widely (professionally done vs. internet ones). I know there is a difference between people's intelligences, I just haven't seen real proof we can put it into a number. --mboverload@ 04:30, 27 June 2006 (UTC)

My IQ society test screen:

400px :)--hello, i'm a member | talk to me! 17:59, 28 June 2006 (UTC)

brazilian essential oils[edit]

Where can I find an overview of typical brazilian plants/flowers which can be used in essential oils?

Thanks, with kindly regards

I have no clue, but Category:Flora of Brazil and Category:Essential oils might somehow help...? Melchoir 07:59, 25 June 2006 (UTC)

Rate of diffusion[edit]

How do you calculate the rate of diffusion? I found 3 or 4 versions on calculating the rate of diffusion but which one is correct? (Does the surface of the solute affect osmosis? Yes it does right?). Many thanks. —Preceding unsigned comment added by 219.78.198.201 (talkcontribs)

According to Graham's law of diffusion (and effusion, but we don't care about that,) the rate of diffusion is inversely proportional to the square root of the density of the gas. -- Миборовский 00:17, 26 June 2006 (UTC)
Note that this, as with all gas laws, only work for ideal gases... bummer. -- Миборовский 00:17, 26 June 2006 (UTC)
I always wondered why it was square root. One would think in a three dimensional environment it would be cubic. Thought that square root would only come into play during fundamental forces, ie. when describing the strength of forces in inverse proportion to distance, but not diffusion. Elle vécut heureuse à jamais (Be eudaimonic!) 04:02, 26 June 2006 (UTC)

How do I calculate the rate of diffusion of distilled water through a semi-pearmeable membrane (potato cylinders)?

Man made lakes[edit]

How are man made lakes made? Where do they get the water from and how are the ones that are connected to the ocean created? —Preceding unsigned comment added by 66.75.254.45 (talkcontribs)

I'm from the Netherlands, where we do the opposite, so I shouldn't be an expert on this. :) The first thing that springs to mind is lakes created by hydro-electric dams. Sort of like beaver-made lakes, just bigger. :) DirkvdM 08:54, 25 June 2006 (UTC)
As far as I know the vast majority of artificial lakes are reservoirs created by damming rivers. They are only 'connected to the ocean' in that the rivers on which they sit eventually reach the sea. HenryFlower 08:57, 25 June 2006 (UTC)
For connection to the ocean, see Zuiderzee Works. --Shantavira 12:17, 25 June 2006 (UTC)
To be complete, there are also man destroyed lakes or inner seas. See irrigation and the like.--DLL 18:28, 25 June 2006 (UTC)

An interesting article for you to check out would be the one about the Salton Sea. Basically, though, all that's necessary is to find an area with a relatively low elevation, dig a trench from that area to the nearest large body of water at a higher elevation, and then let gravity do the rest. Loomis 22:53, 25 June 2006 (UTC)

  • A lake created in a dry river bed, Tempe Town Lake: "using inflatable rubber barriers in the riverbed to confine water within its boundaries". --JWSchmidt 01:27, 26 June 2006 (UTC)
Pumped storage is another twist on this. Rmhermen 18:06, 29 June 2006 (UTC)

Aircraft safety[edit]

I have seen destructive videos of an blade coming loose in a turbine fan of the air intake of a jet engine.Instead,Why cant they make a composite fan and then surround all its blades with a ring,so that even if one blade brakes the plane can still land safely?Guess it would be stronger and lastlonger.

I did not mean a stationary ring on the body of the engine cover,but a ring attached to all the ends of the blades(Something like the rim of a cycle wheel with spokes) that rotates along with the blades

Please see #Aircraft Safety for the previous discussion on this point. Notinasnaid 11:28, 25 June 2006 (UTC)
Well the blades can't get out anyway. I suppose its because it would make incredibly difficult to replace fractured or otherwise damaged blades, possibly to the extenet that a new turbine would have to be installed, whereas at the moment individual blades can easily be replaced, and the engine housing is strong enough to contain the blades anyway, so really, all I can see from it are added costs, and no real benfits. Philc TECI 11:59, 25 June 2006 (UTC)

The design you are talking about is used in some parts of jet engines in the parts called the stator (turbines that remain stationary in the engine). The parts you are talking about using the technique on are called the rotor some reasons the technique is not use on that part is listed below.

The development of turbine blades is a very complicated and costly process. On a large airliner like that of an A380 or and 747 the main fan blades visible as to look at the engine (low pressure assembly) are quite simply massive (larger than most people). Each single blade costs as much as an expensive European sports car they are hollow and made out of complex titanium alloys (super alloys) they need to maintain there shape under excessive g load. Some blades inside the engine on military jets are made of ceramic composites this is usually in the hotter parts of the engine and is used for temperature resistance and there lightness (too reduce inertial of blades). However when blades fail or break it’s usually the large ones at the front that it happens too. The reason that are not held in an arrangement like you said is because of several reasons some listed below

1. Jet engine blades actually stretch over time this has to be allowed for and there length is actually maintained by the blade scraping an abrasive surface inside the jet engine. And different blades may stretch at different rates 2. When turbines fail its usually catastrophic for the engine (it sucks all the broken metal through the moving parts of the engine) if it is not totally destroyed in the process it would be impossible for a jet engine to run without the full number of blades. This is because the engine would be unbalanced and would shake its self too pieces 3. Placing a ring around the outer part of the blades would as a large about of mass to its structure which would massively increase the g force experienced by the root of the blade (the engine would have to be heaver and larger to account for this and hence less efficient)

I’m by no means an expert on jet engine design (I’m a mechanical engineering student) but I hope this helps

Tom

major revisions complete[edit]

The Half-life computation article has undergone substantial revision which has hopefully addressed everyone's concerns. If you have any further comments after looking at the article again, please list the items you do not like, make whatever comment you have and please be specific and allow time for further revision. If there is any reason I can not comply with your wishes then I will let you know the reason why. ...IMHO (Talk) 12:21, 25 June 2006 (UTC)

Why is there so much quibbling about Half-Life? Is it something to do with how many questions about Seagulls are asked on the reference desk?
Remember that the half life of seagulls depends on the various isotopes. --DLL 18:25, 25 June 2006 (UTC)
The application of the concept of half life is so pervasive today that the potential for misunderstanding what it really all about requires that a simple description with examples be provided for the laymen. Otherwise misunderstanding might creep into the technical or political worlds and result in a complete state of Bable. Everybody needs to know exactly what half life is not just mathematicians and scientists. ...IMHO (Talk) 11:23, 28 June 2006 (UTC)

Alternative to internal combustion engine[edit]

I have seen on slashdot and other places on the interweb references to some alternative to or different type of internal combustion engine with massive energy savings which Ford/GM bought the patent to but refused to develop. I had always written it off as a conspiracy theory and ignored it, but i recently heard a respectable scientist refer to it on the radio the other day, so that got me interested. Unfortunately i haven't been able to find any info on it. Anyone know anything? The bellman 15:14, 25 June 2006 (UTC)

The entire purpose of the patent system is to make new discoveries public while giving inventors a period of time with a monopoly on the invention so that they can make money off of it. If there was a patent for the super engine or carburetor, then you should be able to find it at the United States Patent and Trademark Office web page. So, in other words, a patent is unlikely. Without a patent, legal protection of the idea is difficult. It's unlikely that such an invention exists. —209.98.224.158 21:46, 25 June 2006 (UTC)
There are no magic solutions to radically improve the efficiency of internal combustion engines. Things like direct injection give incremental improvements, but that's all. About the only plausible "radical" improvement I've seen is BMW's experimentation with a combined cycle engine - see [3]. To do much better, you have to start doing things like going to fuel cells as a direct replacement. --Robert Merkel 01:33, 26 June 2006 (UTC)
Combustion engines only have an efficiency of under 50% [4], so I'd say there's so much room for improvement that you can't dismiss the idea so easily.
About the patent thing, maybe it wasn't a patent but some other Intellectual property thingy. Many years ago I saw a demonstration on tv of a much lighter and more efficient wheel (yes, someone re-invented the wheel) the rights to which were sold to a car tyre company and they ended with the remark that therefore it was likely that we would never hear from it again because the wheel was too cheap and would therefore not make the manufacturer as much money. And indeed I have never heard of it since. So this sort of thing does seem to happen. The wheel existed of a ribbon-shaped 'tyre' that was attached to the axis with strings in stead of rigid spokes. The result was that the ribbon flattened at the bottom, giving it much more grip than a traditional tyre. DirkvdM 13:32, 26 June 2006 (UTC)
Just offhand about the {tire|tyre} thing, I'd expect that a tire with significantly more road contact area would also have significantly more drag, leading to reduced fuel efficiency (more or less the same as running on tires well below their recommended pressures). So patents may certainly disappear from the market, but it doesn't have to be because of cover-ups.
For the original question, though, it's generally agreed that the problem with replacing internal combustion engines isn't that the technology doesn't exist or isn't known (there are plenty of options) but that few of them are as-yet economical. It's entirely plausible that car manufacturers are sitting on technologies that can't yet be sold for profit. — Lomn | Talk 14:18, 26 June 2006 (UTC)
So we just need to make fuel more expensive.
About the reinvented wheel, it's about 20 years ago, so I can't remember it too well, but it had (in part) something to do with taking turns more easily. A traditional car wheel has to be vertical because its bottom is flat, but this wheel could be at a sharp angle to the gournd and still have the same road contact. And the amount of contact surface can, I assume, be regulated by varying tension on the strings (making them shorter or longer). DirkvdM 18:35, 26 June 2006 (UTC)

Thanks to everyone who answered The bellman 13:11, 27 June 2006 (UTC)

I think you were right in the first place to dismiss this as a conspiracy theory. Here's why:
  1. Ford/GM/Pick-your-auto-company are in the business of selling cars. They are not in the business of selling oil or gasoline or desiel fuel. They have no interest in cars using up a lot of energy. It doesn't help them at all in their goal of selling more cars. In fact, it hurts their goal. The cost of buying the fuel has to be considered in the total cost of ownership for the vehicle. The higher the total cost of ownership, the fewer people can buy the car. If they want to sell more cars around the world, especially to developing nations where the people have less disposable income, then they want the total cost of ownership to be as low as possible.
  2. As pointed out above, the whole point of the patent system is that a company must disclose their invention in exchange for a limited monopoly. If they just let the invention sit there unused, one of 3 things will happen: (a) someone in another country with less respect for our intellectual property laws will just violate the patent (b) someone will sue the owner of the invention to force them to license it - again US law is designed around the notion of advancing society, so the courts are not sympathetic to people who lock up technology and refuse to license it (c) as soon as the patent expires, other people will bring the invention to market.
If we modify your question to suppose it was an an oil company, that the technology was not a more efficient car but rather a replacement for petroleum products, and that the invention was not patented but instead was held as a trade secret then this becomes a little more plausible. Still, oil companies are in competition with each other. They can't be sure that some other oil company on the other side of the world wouldn't independently invent the same thing. There is no security and no profit in keeping the invention hidden and not using it. They would be better off to take the invention to market and instantly make all their competitors obsolete. Johntex\talk 20:04, 27 June 2006 (UTC)

5th state of matter?[edit]

Is there a fifth state of matter what this site: http://www.5th-state-of-matter.info/home.html claims? If so why doesn't it exist in wikipedia. I trust Wikipedia for the moment that there are only 4 states of matter. Please reply if you can

Don't put your email address here, automated bots crawl the web, steal them and send them spam. If you absolutely have to, put them like this: us ern ame <AT> w eb <DOT> c om for username@web.com (with apologies to the actual holder of that address). Wikipedia does not have this information because, from what I can see, the man appears to be a crank (not to put to fine a point on it). I'm sure that other Wikipedians can clarify. That said, if you read our article on states of matter you would realise that there can be many more than 3 if you choose to define them in certain ways. Daniel () 15:57, 25 June 2006 (UTC)
Dbmag9 is right. If anywhere, it belongs at Electric universe (concept). Melchoir 15:59, 25 June 2006 (UTC)
Horay, I'm right about something! Daniel () 17:29, 25 June 2006 (UTC)
Traditionally, plasma is classified as the fourth state, so perhaps a quark-gluon plasma is the 5th state. Eh. --Bmk 04:27, 26 June 2006 (UTC)
Bose-Einstein condensate is often referred to as the fifth form of matter. Looking at the link template at the bottom of that article suggests a lot of other candidates, though. Grutness...wha? 06:49, 26 June 2006 (UTC)

Clinical depression[edit]

Hi! I was reading your article on clinical depression on wikipedia.org/wiki/clinical_depression. You refer under the section 'hypomania' to two specific doctors studies. The first is Hagop Akiskal, M.D. The second is Giovanni Cassano, who is busy with the 'spectrum project'. I would like to get full copies of their studies on 'hypomania'. Can you help me with this information, please?? Kind regards Julie

You can try to locate their journal articles on Medline yourself. Alternatively, you could contact them directly and ask for reprints of their studies/articles. See this website for Giovanni Cassano and here for Dr. Akiskal. - Cybergoth 17:34, 25 June 2006 (UTC)

Stinging and Biting pests[edit]

It seems like every time I allow myself to doze off on my hammock or in my yard, I am soon startled back into wakefulness by an ant bite or some such thing. I may have been moving in my sleep, but probably not very much, and cant imagine that I represented much of a threat to any insect colonies nearby. So why do these insects sting/bite me? Do fire ants and hornets merely cruise around stinging and biting rocks and blades of grass, until they happen upon me? Or do they somehow know that I will react? (By my softness? Plants can be soft. My heat? The sun warms many things. My movement? The wind blows the grasss and the trees too...). This question is specifically applicable to fire ants, which seem to want to bite me even when I sit on my granite bench in the garden and hold perfectly still.Tuckerekcut 14:27, 24 June 2006 (UTC)

I posted this a few days ago but someone deleted it, that wasn't very nice. (And can someone get rid of the box? I don't know how to...)Tuckerekcut 18:02, 25 June 2006 (UTC)

The box appears when you insert an initial space in front of the first word of the paragraph; I've removed it now. —AySz88\^-^ 18:06, 25 June 2006 (UTC)
Thank You. Tuckerekcut 18:19, 25 June 2006 (UTC)
Insects allow the USA to earn billions each year : they pollinate plants, but they also bite and digest dead things. So doing their job, they just taste you in case of. --DLL 18:22, 25 June 2006 (UTC)
Unfortunately, it is the nature of fire ants to bite you because they smell you and perceive you as a threat. You will either need to find somewhere else to sit, or move them on. According to the article, you need to get yourself a few ant-decapitating flies. --Shantavira 18:27, 25 June 2006 (UTC)
How do those ant-decapitating flies get the ants to stay still long enough to lay an egg on its head? The fly must be massive compared to the ant... surely it would notice?!?!? --Dweller 09:38, 26 June 2006 (UTC)

So it is primarily through chemoreception that biting insects choose their targets, I guess I should have suspected that. Does that mean that the ants will bite the granite bench I sat on (for this example, we will suppose that I sat on it nude) soon after I stand up? My chemical smell would remain on the surface for a while... However, I should point out that, say, hornets, will sting animals digging into their nests, but usually not animals lounging far away, both should smell just about the same. And to extrapolate this example further, will the hornets sting the digging animal with the same ferocity that they would sting a mechanical shovel? What if that shovel was soft? or warm? Tuckerekcut 22:09, 25 June 2006 (UTC)

Rehydrating drinks[edit]

do carbonated beverages and soft drinks rehydrate you?

Gatorade has a fair bit of salt in it. Does gatorade rehydrate you?

I've heard ocean water has a fair bit of salt in it. Does ocean water rehydrate you?

Thanks ~Peter

You can get water from anything less salty than urine. Soft drinks and gatorade are less salty that urine, but seawater is more salty, so the more you drink the more water you have to waste to get rid of the salt. —Keenan Pepper 19:13, 25 June 2006 (UTC)
That statement can be misleading, as Urine varies in salt concentration in accordance with your water intake. Philc TECI 19:34, 25 June 2006 (UTC)
The best drinks for rehydration are sports drinks such as Gatorade. Water is also good for mild dehydration, although it does not replenish salts lost through sweating or urination and an excess can cause water toxicity. Drinking sea water is worse than drinking nothing for rehydration, as it has a salt concentration of about 3.5% (far lessmore than that of blood). Sweetened soft drinks are better than nothing for rehydration, but are not the most effective because they both lack salts and contain sugar, which is hygroscopic. Also, many soft drinks are caffeinated, and caffeine is a diuretic, increasing urination and therefore interfering with rehydration. Alcoholic beverages are also diuretic and should be avoided when dehydrated. --Ginkgo100 talk · contribs 19:55, 25 June 2006 (UTC)
That is quite interesting. --Proficient 20:23, 25 June 2006 (UTC)

Ocean water does not rehydrate you. It has way too much salt and will harm you, not help you in case of dire thirst.User101010 21:46, 25 June 2006 (UTC)

Dehydration can result from problems controlling not just the volume of water in the body (hypovolemic dehydration) but also the concentration of soluble chemicals (osmotic dehydration). Gatorade is made to replenish the body of both water (for liquid volume) and salts (for osmotic regulation) to replace liquids lost through sweating, and as such it is a good choice for rehydration when you are dehydrated due to fluid loss (sweating, diabetes insipidus, diarrhea, and I suppose bleeding, if the only chioice is to drink something). however, if you are already getting enough salt from other parts of your diet, then it is better to drink plain water. For other drinks, remember that diuretics will cause you too lose more water than salt, which may lead to an undesireable osmotic situation, so avoid alcohol and caffiene when you are dehydrated. The actual carbonation in soft drinks is of little nutritional significance, most of it fizzes out and the remaining carbonic acid won't really effect hydration. However, as Ginkgo points out above, the sugar constituent of soft drinks is hygroscopic (that means that water molecules tend to gather around the molecules of sugar, making them less biologically available). Because of this, and the fact that sugar, by weight is far less "concentrated" in an osmolar sense (the molecules are big, and they don't ionize like salts), sugary drinks are not nearly as good as salty drinks at controlling osmotic dehydration. As for saltwater, don't ever drink it. Saltwater is just a tiny bit saltier than your body's natural fluids, so even if your stomach is full of saltwater, your cells will actually give up water to dilute it, even if it means dehydrating themselves. Body fluids have a salt concentration of about 0.9 g of table salt per liter of water, anything more concentrated will be able to replace water volume, but will not be able to restore osmotic balance. This all sounds a little complicated, but if you do a little searching, you may find it is deviously simple, I recommend looking at the following articles if you find yourself confused: osmosis, renal system, hypernatremia, hyponatremia, hypovolemia, thirst. Tuckerekcut 22:49, 25 June 2006 (UTC)

I thought that not only salt, but sugar also increased the osmotic value of a solution and since soft drinks are so full of sugar, they also cause dehydration. DirkvdM 14:21, 26 June 2006 (UTC)
Any solute in water will increase its osmolarity, the reason that "sugar" is less effective than "salt" is twofold. First, Sugar molecules are much more massive and voluminous than salt molecules (sugars being, at the smallest, C6H12O6 (about 180 g/mole), with table salt (NaCl) around 58 g/mole) therefore one gram of sugar has far fewer molecules than one gram of salt, and in osmosis, the only thing that matters is how many individual molecules or ions are floating around. Second, sugar remains a single molecule when dissolved in water, so one mole of dry sugar yields one mole of molecules in solution (1 molar = 1 osmolar). Salt, on the other hand, ionises in water, and thus one mole of salt yields two moles of ions in solution (1 molar = 2 osmolar). (Also, simple sugars are hygroscopic, which means that they readily absorb water. This is mentioned above, but it only effects bioavailability, not osmolarity). The upshot of all of this is that a gram of salt is roughly six times more osmotically active than a gram of sugar. Sugar does effect osmolarity, but not nearly as much as salt. Assuming "normal" dehydration (hypovolemia with hypernatremia), something like D5 W (water with 5% dextrose sugar w/v) would be a more effective rehydrator than gatorade.Tuckerekcut 15:59, 26 June 2006 (UTC)
Ok, I already got that, basically (although the expansion helped), but we're comparing a pinch of salt with bucketloads of sugar. Well, that's somewhat exaggerated. :) But soft drinks tend to contain loads of sugar, don't they? Something like one third or even half the content? I'd check on a bottle, but I never dirnk the stuff, so I don't have any around. However, as a kid I drank loads of coca cola and I was pretty fat then. Plus it ruined my stomach and rotted my teeth. But that's a different issue. DirkvdM 18:41, 26 June 2006 (UTC)

Let's do the math! Gatorade orange flavor vs. Jones Fufu Berry Soda (sorry, it's all I have).

Gatorade: serving size 240 ml
14 g sucrose/glucose-fructose, we will assume that that is 14 g of pure sucrose (easier and not sig. diff.)
110 mg Na
30 mg K
sucrose is 342 g/mole. 14/342=0.04mole in 240 ml = 0.17 M w/ respect to sugars
sodium is 23 g/mole. 0.11/23=0.0048mole (multiply by two to account for the cation)=0.0096mole in 240 ml = 0.04 M w/ respect to sodium salt.
potassium is 39 g/mole. 0.03/39=0.0008mole (multiply by two to account for the cation)=0.0016mole in 240 ml = 0.007 M w/respect to potassuim salt

Thus the total osmolarity of Gatorade is approximately 0.22 M

Soda: serving size 355 ml
46 g fructose
20 mg Na
fructose is 180 g/mole. 46/180=0.26mole in 355 ml = 0.73 M w/ respect to sugars
sodium is 23 g/mole. 0.02/23=0.0009mole (multiply by two to account for the cation)=0.0018mole in 355 ml = 0.005 M w/ respect to sodium salt.

Thus the total osmolarity of this soda is approximately 0.74 M It seems that the soda has significantly higher osmolarity than Gatorade.Tuckerekcut 20:54, 26 June 2006 (UTC)

The Oral rehydration therapy article, says "In the human body, the plasma osmolality is about 285 mOsm/l". Which, I assume, means an osmolarity of 0.285 M (I don't know these units, but it looks pretty decimal). And anything over that would have a dehydrating effect, right? So at least this soft drink has a dehydrating effect and would thus even be lethal if you drink enough of it. How much would an average person (say 70 kg) have to drink to die?
Btw, I've also heard of the opposite - a woman swallowed some detergent or something, called the doctor, who said she should drink loads of water and he'd be right over. Upon which she drank so much water that her cells burst and she died. Is this possible? DirkvdM 07:37, 27 June 2006 (UTC)
The plasma osmolarity you mentioned is probably pretty close (but surely a little less) than the intercellular osmolarity in the human body. Drinking anything with a higher osmolarity than the fluid inside your cells will cause them to lose water and dehydrate. However, drinking anything with an osmolarity lower will cause water to enter the cells, which will eventually cause them to burst (the possibility from your second example). This is why we have a renal system. The kidneys are able to fine tune (and, i suppose "gross tune") the osmolarity of your blood by either creating watery urine to excrete excess water or creating concentrated urine to excrete excess salt/sugar/whatever. So really, while it is possible to kill oneself by drinking too much water or too much soda (too much of anything will kill you, doncha know..), it's not all that easy, as the kidneys are always fine tuning the blood to keep it in the "sweet spot". I'm not even gonna hazard a guess as to how much soda one would have to drink in a day to become critically dehydrated, but probably the huge increase in blood sugar would cause a hyperglycemic coma before it caused dessication.Tuckerekcut 15:47, 27 June 2006 (UTC)
But what if someone drank nothing but soft-drinks? Would that eventually be lethal? Of course one also takes in fluids through food, so maybe that would be sufficient compensation (although it would still be very unhealthy). But many years ago there was a Coca Cola commercial in which someone was wandering through a desert, overheated and dehydrated, but was rescued by a miracle Coke vending machine. Which of course sold ice-cold Coke. Which would have killed him in two ways - he'd get dehydrated even more, but that wouldn't matter because drinking cold fluids when overheated would kill him first. At the time I wondered if such a commercial should not be illegal because, although the specific situation was unrealistic, it gave a very unhealthy suggestion. (I also added this to the Coca Cola article a while back, but that got instantly reverted :( ). DirkvdM 06:21, 28 June 2006 (UTC)
A person with good kidney function could probably get away with drinking only soda and be relatively okay. A drink with the osmolarity of soda would only dehydrate you if your kidneys were non-functional. As long as they are around to excrete concentrated water, even a drink as concentrated as soda would be able to rehydrate you. My statement about lethality of non-isotonic solutions only applies to rapid and voluminous addition of liquids to the body. To drink enoough water or soda to kill yourself would be very difficult, painful, and laborious. Indeed you mentioned that one can even get water from food. Surely you recognize that most foodstuffs are more "concentrated" than even the sugariest of sodas. Even alchoholic drinks can hydrate very dehydrated people, as the body's ADH levels become high enough to counteract the diuretic properties of ethanol. You also mentioned that a cold drink would kill an overheated person. This is unlikely, as in the worste case senario, the individual wouldn't do much more than vomit. Perhaps you are thinking of the inverse situation? Rapid warming of a hypothermic person can introduce dangerously cold blood to the heart, but rapid cooling of a hyperthermic individual is indeed prescribed in most cases.Tuckerekcut 16:54, 28 June 2006 (UTC)
Could someone with a good kidney then also survive drinking seawater? Or is the osmolarity higher still? Or is it that after too much time on a raft at sea one is too weak?
About a cold drink being lethal to an overheated person, apparently that happened to a relative of mine over a century ago, who helped set up a weaving factory in Poland, and one day after doing a lot of hard work in a hot room asked for a big glass of ice cold beer, downed it in one go and dropped dead on the spot. Or so the story goes. Of course vomiting would be a logical reaction. But there's also the shock, which could in itself be lethal to the weakened desert wanderer. I was also thinking about the fact that drinking cold drinks when one is hot has the opposite effect of what one might expect because the body core needs a constant temperature, so it will start to generate even more heat and you'll feel even hotter. But then that doesn't really sound lethal. DirkvdM 19:07, 28 June 2006 (UTC)

Yeah, you can drink seawater, assuming you have healthy kidneys (two of 'em ;-) ), and not suffer any damage (the osmolarity of seawater is about 0.6M). It has come to my attention that the soda I used as an example above is atypically concentrated, usually a soda is closer to 0.4 - 0.5M. In any case, you would need to use a lot of energy to "filter" out that sea salt, and it would be severely detrimental to drink seawater when you are already dehydrated, as you would be making your kidneys work even harder, and they can only concentrate urine to a certain extent...

I'm not sure what mechanism killed your relative, but If you have any more information or any citations I would be interested.Tuckerekcut 20:24, 29 June 2006 (UTC)

Engineering Software[edit]

I am looking for an software which could do the beam deflection. Please send me some name. If threre are any open source software please send me the name. —The preceding unsigned comment was added by 208.110.17.154 (talkcontribs) .



What kind of "beam deflection"? Your question needs more context. —Keenan Pepper 19:17, 25 June 2006 (UTC)
Electron or wood? —209.98.224.158 21:54, 25 June 2006 (UTC)
Maybe the person who asked the question was looking for ray tracing software.--72.78.101.61 04:14, 26 June 2006 (UTC)
Have you googled? –Mysid(t) 07:44, 26 June 2006 (UTC)

There are some softwere packages out there that can do this sort of thing. one that springs to mind in MDsolids do a serch for it with google and you will find it. Leave the capitals in the spelling as its important. its comes with a free trial so you can see if its for you. its pritty cheap and i have found it usefull in my engineering studies.

Tom

Condoms[edit]

How many times can I reuse a condom before I have to replace it?

Well, once. Unless your somewhat disgusting. Philc TECI 19:38, 25 June 2006 (UTC)
Unless you're also disgusting, Philc, I assume you've been caught by a tautology and you really mean "none". --Dweller 09:32, 26 June 2006 (UTC)
They're usually disposable. --Proficient 20:24, 25 June 2006 (UTC)
Never use a condom more than once. Always use a new condom for each separate act. Once the condom is removed, the bodily fluids can go anywhere, so an old condom can easily transfer bodily fluids. If you're lucky enough to get seconds, then use a second condom. One condom is far cheaper than the costs of a pregnancy and/or medical care for an STD. According the wikipedia article on condoms, the typical effectiveness of condoms is only 85%. If you re-use it, that number will drop even further. User101010 21:16, 25 June 2006 (UTC)
You are assuming the questioner is referring to a disposable condom. Older condoms, commonly made from the intestines of goats, pigs, and the like, are not disposable and intended to be used indefinately. While it is highly unlikely that anyone would be using such a condom in modern times, I feel that a reference desk answer should be complete. So, I wanted to note on this special sort of condom. --Kainaw (talk) 23:09, 25 June 2006 (UTC)

Oh, if you are talking about the steel condom [5] I believe you can use it forever. Just place it in the dishwasher after use! --Zeizmic 01:11, 26 June 2006 (UTC)

What the hell!? A steel condomn!? Well, I suppose I could get one if I wanted my parter to experince a softer sensation. Mayor Westfall 05:20, 26 June 2006 (UTC)
It was certainly possible to buy reusable condoms in the 1970s. They came with cleaning instructions, talc, and a "re-rolling machine". Useful for kids on a budget who were only - er - practising on their own.--Shantavira 06:27, 26 June 2006 (UTC)
About being on a budget. I buy my condoms at less than 20 euro per gross. That's just over 10 cents per condom. Condom prices are hugely inflated, just like funerals - who is going to complain about the price at such moments? DirkvdM 14:28, 26 June 2006 (UTC)
You can get the family pack. - Cybergoth 21:56, 26 June 2006 (UTC)
Early condoms were made of vulcanized rubber or animal membranes. These were reusable. Modern latex condoms are not reusable. - Cybergoth 21:55, 26 June 2006 (UTC)

Reading faces, liver lines etc.[edit]

Somewhere in my study of macrobiotics a few years back, I heard about a book (chinese medicine) that told how you could read peoples faces. One that I remember is "liver lines" 2 vertical lines on the middle of the forhead. The other I remember........the lips had something to do with the bowels. Can anyone enlighten me on this subject, or refer me to a book about it?

Thank you very much Marie Wasilik

You're looking for the meridian (TCM) network in traditional Chinese medicine. This picture shows the most important meridians. -- Миборовский 00:11, 26 June 2006 (UTC)
No, I don't think the question was about meridians/accupuncture. Try Google? - Cybergoth 21:51, 26 June 2006 (UTC)

The reference was probably from a book on Bo Shin - the art of facial diagnosis. A good beginning is "Your Face Never Lies" by Michio Kushi.