Wikipedia:Reference desk/Archives/Science/2012 June 26
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June 26
[edit]Sucking on a button to combat dehydration?
[edit]![](http://upload.wikimedia.org/wikipedia/en/thumb/f/fb/Yes_check.svg/20px-Yes_check.svg.png)
In the movie Cube (film), the characters are stranded without water. One of the character swallows a buttons and claims it "keeps the saliva flowing". Does this trick actually work? I have my doubts because a small pebble would work just as well as a button so if this technique really worked it would have been discovered millenniums ago and be much more well-known. Anonymous.translator (talk) 00:12, 26 June 2012 (UTC)
- Army trainees on maneuvers in the desert around Fort Bliss, Texas, during WWII used to be told to suck on pebbles to allay their thirst; I used to know one such veteran who told me that. Never tried it to see how effective it is, myself. But yes, the technique is an old one, not unknown. Textorus (talk) 00:17, 26 June 2012 (UTC)
- Like text says, if it allays anything, it might allay thirst. But that's not going to actually fight dehydration. It's not like your body can just make new water for the saliva. Someguy1221 (talk) 00:21, 26 June 2012 (UTC)
- Wow, 5 minutes. Thanks for the quick answer, guys. Anonymous.translator (talk) 00:28, 26 June 2012 (UTC)
- My old Scout Leader in the UK told us about sucking pebbles to prevent thirst on a hot day. We thought that it fell (like much of his advice) firmly into the bracket of old wives' tales. Alansplodge (talk) 00:45, 26 June 2012 (UTC)
- Some more old wives here, here, here and here. Alansplodge (talk) 00:54, 26 June 2012 (UTC)
- My old Scout Leader in the UK told us about sucking pebbles to prevent thirst on a hot day. We thought that it fell (like much of his advice) firmly into the bracket of old wives' tales. Alansplodge (talk) 00:45, 26 June 2012 (UTC)
- I remember reading about sucking on pebles in Baden-Powell's book Scouting For Boys when I joined the Scouts in the 1960's. This book had been published about 50 years before but was still the primary text for boy scouts (10 to 12 year olds) at that time. I think Scouting For Boys would be the original source for the pebbles advice. I don't have the book now, but I think the advice was aimed at distracting boys from wanting a drink too often while on treks (as the average boy would be accustomed to having a drink any time he liked at home), and not expected to counter genuine thirst, and certainly not dehydration. Other advice in the book was very good, as I recall (except the advice to help old ladies across streets - I tried that once and got told "piss off sonny"). Wickwack120.145.57.11 (talk) 04:10, 26 June 2012 (UTC)
- Old boy, the book is scanned here and it still makes a jolly good read. It doesn't mention any "pebles" but says: "If you keep your mouth shut when walking or running, or keep a pebble in your mouth (which also makes you keep your mouth shut), you do not get thirsty as you do when you go along with your mouth open, sucking in the air and dry dust." pp. 160 Scouting for Boys. "When in the street, always be on the look-out to help women and children. A good opportunity is when they want to cross a street, or to find the way, or to call a cab or bus. If you see them, go and help them at once - and don't accept any reward." -- ibid. pp. 178 DriveByWire (talk) 17:51, 26 June 2012 (UTC)
OP, I'm interested in the verb "shallows" in your question. At first I assumed it was a typo for "swallows", but surely you weren't talking of swallowing buttons or pebbles, and the header is about sucking, not swallowing. I checked wikt: shallow but it has no meaning equivalent to "suck". Can you explain this word "shallow" to me, please? -- ♬ Jack of Oz ♬ [your turn] 19:03, 26 June 2012 (UTC)
- Typo.Anonymous.translator (talk) 20:14, 26 June 2012 (UTC)
- As a side note, this is how I [1] handle typos.Anonymous.translator (talk) 20:20, 26 June 2012 (UTC)
- Thanks, but I still don't understand why you'd be advocating the actual swallowing - not just sucking - of small pebbles. Did you really mean physically ingesting of anything that's not food and not digestible and potentially harmful? -- ♬ Jack of Oz ♬ [your turn] 20:31, 26 June 2012 (UTC)
- As a side note, this is how I [1] handle typos.Anonymous.translator (talk) 20:20, 26 June 2012 (UTC)
- I tried the pebble trick as a Scout, and it did not seem to accomplish anything toward "reducing thirst." If 1,000,000 kids each picked up a pebble from the ground and walked around for a few hours with it in his mouth, how many would become ill from crud deposited on the pebble while it was on the ground, how many would accidentally get the pebble stuck in his windpipe, requiring a Heimlich maneuver or tracheotomy, like other boys who placed pebbles in the mouth to keep it moist?See also another case of a 7 year old who had a pebble held in the mouth slip into the trachea. Edison (talk) 13:25, 27 June 2012 (UTC)
Discovery of Uranium in Russia
[edit]I am withdrawing this question.
Medical treatments for "Exhaustion"
[edit]This is not a request for medical advice, but for referenced information about hospital treatments for this condition, not presently found in the relevant Wikipedia article. There are news stories from time to time about celebrities, musicians, actors, and politicians hospitalized for "exhaustion." Searching for this malady in Wikipedia, one finds a redirect to Fatigue (medical). Leaving out obvious and readily treated causes of various forms of the malady such as physical muscular fatigue (someone trying to swim 100 miles), or sleepiness after staying awake for 4 days, there remains a vague condition. I once read an article (citation not at hand) which said that ordinary people are never hospitalized for "exhaustion" as are celebrities, whose exhaustion may consist of substance abuse, eating disorders, dehydration, "burnout," stress or depression. The "exhaustion" description is sometimes said to be a public relations code word for mental health issues and substance abuse. The relevant Wikipedia article does not describe how exhaustion is treated in a hospital. Any reliably sourced info for current medical practice in treating "exhaustion" in those hospitalized for it? Edison (talk) 04:00, 26 June 2012 (UTC)
- No useful answer can be given beyond "rest", as the treatment would vary enormously depending on cause and symptoms, which, as you note, vary enormously themselves. Dominus Vobisdu (talk) 04:12, 26 June 2012 (UTC)
- Agreed. The only way that true exhaustion wouldn't be solved by rest is if they have a sleep disorder, and then the hospital/clinic would diagnose and treat that.
- Also note that lack of sleep and substance abuse are often combined in celebrities, like Judy Garland, Marilyn Monroe, and, more recently, Micheal Jackson. They can take (or be forced to take) drugs to keep them going while filming, rehearsing a concert tour, etc. A nasty cycle can form where they take "pep pills", such as amphetamines, to stay awake, then take sleep meds to sleep, gradually upping the dose of each to counter the other. In such a case, the hospital/clinic would need to treat the drug addiction first. Then, after they recover, hopefully they can be less ambitious, and maybe do only half as many concerts or movies, or as many as they can handle in a healthy manner. StuRat (talk) 04:14, 26 June 2012 (UTC)
- "Exhaustion" is a symptom, not a condition, and it would be possible to be hospitalised with that symptom while the physical cause of the exhausion is investigated. Conditions such as some endocrine disorders (hypothyroidism, myasthenia gravis) could be indicated. --TammyMoet (talk) 09:19, 26 June 2012 (UTC)
"Exhaustion" in these cases invariably means drug or alcohol abuse and its after-effects. μηδείς (talk) 17:13, 26 June 2012 (UTC)
- In the article I read years ago, a doctor or nurse asserted that a publicist may tell reporters that a celebrity was "hospitalized for exhaustion," but that within the hospital, that would not be the diagnosis, illness, or condition shown on the patient's chart, which might indocate detox from painkillers, alcohol etc, or treatment for depression. Yet our article lists diagnosis codes for "exhaustion" per se. So might a patient's chart actually indicate he is "exhausted" and so needs to be in a hospital bed for some days to become "unexhausted?" Edison (talk) 13:09, 27 June 2012 (UTC)
What are galaxies made of?
[edit]![](http://upload.wikimedia.org/wikipedia/commons/thumb/a/a2/SN1994D.jpg/220px-SN1994D.jpg)
How do we know that galaxies are made of stars instead of gas? Have anyone taken a picture of a galaxy which one can see individual stars in it. The milky way does not count. If we cannot see individual stars in a picture of a galaxy what's to say that it is not made up of gas instead? Maybe it's all just gas swirling around a big black hole. 220.239.37.244 (talk) 12:42, 26 June 2012 (UTC)
- Yes, we can easily resolve individual stars in many other galaxies. Up until the middle of the 1920s there was a debate, but then Edwin Hubble first identified individual stars in some near galaxies. See Great Debate (astronomy). --Stephan Schulz (talk) 13:00, 26 June 2012 (UTC)
- And occasionally we see them blow up. Blakk and ekka 15:30, 26 June 2012 (UTC)
- Galaxies glow; big clouds of gas do not. If galaxies did not contain lots of glowing stars, we could not see the galaxies. There are big clouds of gas and dust around which don't contain stars, and we can only detect them when the pass between us and glowing things, the light of which they obscure. -- Finlay McWalterჷTalk 13:08, 26 June 2012 (UTC)
- Nebula don't glow? ScienceApe (talk) 15:16, 26 June 2012 (UTC)
- Nebula only glow because there are stars in or behind them which are lighting them up. There's no know process where a large, diffuse (cold) cloud of gas by itself can sustain light output for a prolonged period of time. If galaxies outside the milky way were just gas, they wouldn't be visible, as they wouldn't be able to emit light themselves and there would be nothing behind them to illuminate them. (P.S. Galaxies are made up of both stars *and* gas.) -- 71.35.99.136 (talk) 15:36, 26 June 2012 (UTC)
- Clusters of galaxies as well as large elliptical galaxies are embedded in hot tenuous gas that radiates in X-rays. This gas is hot because it's in a deep gravitational potential well (it attained its temperature through shock heating when falling into the cluster potential), not because it was heated by stars. In the early stages of galaxy formation, before stars were formed, you could imagine a potential well just being filled with (glowing) gas. The things closest to that scenario are probably Lyman-alpha blobs. --Wrongfilter (talk) 15:45, 26 June 2012 (UTC)
- Well then doesn't it stand to reason that there might be a lot of gas in galaxies that we can not detect, and therefore the so called "missing mass" from galaxies does not exist, and that dark matter is probably just undetectable gas? ScienceApe (talk) 18:02, 26 June 2012 (UTC)
- No, because we could detect them, due to their absorption spectrum effect on the light from the stars behind them. The missing mass must neither emit nor absorb light or other frequency on the EM spectrum. StuRat (talk) 18:07, 26 June 2012 (UTC)
- It's actually not such an easy problem. The majority of astronomers don't think that gas could account for dark matter, but there is a minority who aren't sure, and the arguments are pretty difficult. Looie496 (talk) 18:18, 26 June 2012 (UTC)
- The article on dark matter doesn't make any mention of gas as a possible explanation. The only alternative hypotheses it lists are to do with alternate theories of gravity. As I understand it models of galactic evolution put the bulk of dark matter in dense "halos" above the galactic plane, so if dense clouds of gas were present there, they would be easily detectable. 112.215.36.174 (talk) 10:33, 30 June 2012 (UTC)
- It's actually not such an easy problem. The majority of astronomers don't think that gas could account for dark matter, but there is a minority who aren't sure, and the arguments are pretty difficult. Looie496 (talk) 18:18, 26 June 2012 (UTC)
You might want to read the articles on Uniformitarianism and Astronomical spectroscopy. We do not need to assume, but can directly observe that the laws of chemistry are the same everywhere. μηδείς (talk) 17:11, 26 June 2012 (UTC)
Why does new year start from Jan 1? Why not synchronize it to vernal equinox or winter solstice?
[edit]why is the gregorian calendar designed so that new year starts from where it starts now? wouldn't it be better if the new year started from a day more remarkable like one of the solstices or equinoxes? 117.216.157.33 (talk) 17:12, 26 June 2012 (UTC)
- Well, the solstices and equinoxes aren't always on the same calendar day every year, so that would make it difficult to tell on any given year when the new year even starts. Mingmingla (talk) 17:56, 26 June 2012 (UTC)
- You're saying in effect that it would not be the simplest thing in the world to convert between the Gregorian calendar and a solstice– or equinox-based calendar; but that's not a valid point against the latter. —Tamfang (talk) 20:42, 26 June 2012 (UTC)
- We start the year on January because the Julian calendar, which 2,000 years ago was already the same as what we use now, except for one rule, started on January. If it were on the winter solstice, say, you couldn't say "December 2012" because then it'd be like which December 2012?, the one before the solstice or the one after? Now you could change the months to start on the equinox but why!? We've accumulated a large number of laws, records, birthdates, and holidays that would all have to be changed if we did that. You'd have to relearn everything. What day will be Christmas? NewJanuary 4th? Ultradecember 5? Halloween will be SuperOctober 10. Titanic sinks SubApril the 26th. And either the current August 21st would have to be fall or June 20th in spring, for the Northern Hemisphere, which doesn't seem right. Sagittarian Milky Way (talk) 18:04, 26 June 2012 (UTC)
- Excepting all of mine, best help-desk post ever! μηδείς (talk) 03:16, 27 June 2012 (UTC)
- hehe, yeah i agree on the uselessness of the excercise. but many other calendars roughly coincide with spring equinox as new year, so i thoght it might be probable that the new year was actually designed to start on winter solstice, but over time, has moved 10 days further due to various probable reasons (historical, astronomical, etc). just a thought. 117.216.157.33 (talk) 18:40, 26 June 2012 (UTC)
- I don't think the new year was reckoned as starting on January 1 until the late 18th Century. It used to start on March 1. thx1138 (talk) 18:42, 26 June 2012 (UTC)
- I was wrong, it's more complicated than that: Gregorian calendar#Beginning of the year. Anyway, the reason the Julian calendar originally used January 1 as the beginning of the year is because at that time, that's when Roman consuls started their terms of office. thx1138 (talk) 18:45, 26 June 2012 (UTC)
- hmm, that's pretty arbitrary. too bad, I was hoping to find a more interesting answer :P
- I was wrong, it's more complicated than that: Gregorian calendar#Beginning of the year. Anyway, the reason the Julian calendar originally used January 1 as the beginning of the year is because at that time, that's when Roman consuls started their terms of office. thx1138 (talk) 18:45, 26 June 2012 (UTC)
- I don't think the new year was reckoned as starting on January 1 until the late 18th Century. It used to start on March 1. thx1138 (talk) 18:42, 26 June 2012 (UTC)
Could it be that January 1 was the winter solstice at one time in the distant past?165.212.189.187 (talk) 18:44, 26 June 2012 (UTC)
- Jan 1 was once the solstice in the Julian calendar, but before there were Romans. That's only because of the Julian calendar's inability to track it well, not because it really moved that much. Sagittarian Milky Way (talk) 19:43, 26 June 2012 (UTC)
- so it might not be all that arbitrary at all? 117.216.157.33 (talk) 19:59, 26 June 2012 (UTC)
- Jan 1 was once the solstice in the Julian calendar, but before there were Romans. That's only because of the Julian calendar's inability to track it well, not because it really moved that much. Sagittarian Milky Way (talk) 19:43, 26 June 2012 (UTC)
- my doubts are exactly the same. 117.216.157.33 (talk) 18:47, 26 June 2012 (UTC)
- Just a guess, but Christmas day is on the 359th or 360th day of the year, so I'm thinking they wanted 360 "normal days", ending in Christmas, which makes for 12 months of exactly 30 days, followed by 5 extra days, at the end of the year. StuRat (talk) 18:51, 26 June 2012 (UTC)
- But according to Gregorian_calendar#Beginning_of_the_year, Jan 1 was new year since 153 BC; before the tradition of christmas started. 117.216.157.33 (talk) 19:00, 26 June 2012 (UTC)
- When was Saturnalia, the Roman pre-Christian festival? Maybe it had something to do with that.
- Yes, they may have positioned Christmas at that time of the year, since nobody really knows when Jesus was born. StuRat (talk) 19:54, 26 June 2012 (UTC)
- All these dates come in a very small range (arnd 10 days within each other); so it might be possible that some shift might have taken place either due to faulty calculation of dates or (less likely) due to some astronomical phenomena (i dunno, slowing down of earth, or whatever)
- Yes, they may have positioned Christmas at that time of the year, since nobody really knows when Jesus was born. StuRat (talk) 19:54, 26 June 2012 (UTC)
- uh....::::precession....!?68.83.98.40 (talk) 04:37, 27 June 2012 (UTC)
- No precession. In 12,000 years the winter constellations will be best viewed in summer and have had to have been renamed twice. Same for the other seasons. And how wrong the Western sun signs are changes by 1 day every 70 years. (Because they refuse to just rename them 1, 2, 3 and 4 after they grow out of date) But but that's about it. If the solstice is changing by 10 days in 1,000 years then one day it will be snowing in June, and your calendar is not doing it's job, not that anything's moving. (Well, it's not possible to make a perfect season tracking calendar as the eccentricity of the Earth makes the solstices and equinoxes move around a bit, but the it shouldn't ever get further from it's average date by about 21/3 days (and even that takes longer than our months have existed), plus 1¼ day if you have to wait 400 years for the all the leap days to average out like this:
.
- Add 1 more day inaccuracy every 3,200 years away from now due to a need for longer term leap year rules, or maybe not, this is beyond our predictive abilities). I'm pretty sure no one had thought of January yet when the Julian solstice was on January 1. Season seems to indicate that they started their year at March because it was the start of spring (when it was warm enough to make wars again, typical Romans), so that might be why the months start when they do. Rome winters end earlier than most of the Western civilization that adopted it's calendar, due to it's mediterranean climate, so I assume that's why they didn't make their seasons a little later. Maybe it's not so bad. Though Mother Nature sometimes has the nerve to make it too cold to skinny dip and sleep outside naked well into June, and it's still warm in early Sept., it's not very bright then and the long days are a part of summer too, right? Sagittarian Milky Way (talk) 20:37, 27 June 2012 (UTC)
- No precession. In 12,000 years the winter constellations will be best viewed in summer and have had to have been renamed twice. Same for the other seasons. And how wrong the Western sun signs are changes by 1 day every 70 years. (Because they refuse to just rename them 1, 2, 3 and 4 after they grow out of date) But but that's about it. If the solstice is changing by 10 days in 1,000 years then one day it will be snowing in June, and your calendar is not doing it's job, not that anything's moving. (Well, it's not possible to make a perfect season tracking calendar as the eccentricity of the Earth makes the solstices and equinoxes move around a bit, but the it shouldn't ever get further from it's average date by about 21/3 days (and even that takes longer than our months have existed), plus 1¼ day if you have to wait 400 years for the all the leap days to average out like this:
- uh....::::precession....!?68.83.98.40 (talk) 04:37, 27 June 2012 (UTC)
- Until recently, Christmas wasn't a big deal, unlike Easter. —Tamfang (talk) 20:42, 26 June 2012 (UTC)
- If I were Pope Gregory's advisor I'd say: each month shall have 30 days until some month ends or begins on a solstice or equinox, and thereafter the sequence shall be 30 31 30 31 30 31 30 31 30 31 30 30¼. —Tamfang (talk) 20:42, 26 June 2012 (UTC)
- No, because the goal was to bring the day of the vernal equinox back to when it was at the First Council of Nicea (325AD). Unless skyviewcafe.com is sufficiently inaccurate, it seems they chose the correct number of days to drop (whether Rome, Jerusalem or Nicea local mean time doesn't make a difference). What's puzzling is why it's mentioned alot that they wanted March 21 when they knew the year to less than a minute of accuracy. March 20 is closer, both in 325 and in 1582. It seems like if anything they wanted March 20. It was March 21st around 200. Maybe the current Easter rules (equinox, full moon, sunday) were developed around then? Also, how would you make a month 30¼ days long? Have it end at 6am? Sagittarian Milky Way (talk) 21:38, 26 June 2012 (UTC)
- Since no one already said this: The current calendar has a month of 28¼ days, in the sense intended. —Tamfang (talk) 06:23, 2 June 2018 (UTC)
Roman calendar gives more info about older calendars. In particular, Martius/March was once the first month, as is evidenced even now by the names of September through December. The OP would have been happier then: "Roman writers claimed that their calendar was invented by Romulus, the founder of Rome around 753 BC. His version contained ten months with the vernal equinox in the first month". The insertion of January & February is attributed to Numa Pompilius.John Z (talk) 03:43, 27 June 2012 (UTC)
- Note to non-classicists: septem, octo, novem, decem = 7, 8, 9, 10. QED. Ghmyrtle (talk) 13:37, 27 June 2012 (UTC)
Is it possible to make a sneaker that makes you run faster?
[edit]Topic says it all. ScienceApe (talk) 18:00, 26 June 2012 (UTC)
- With little rocket engines on the back, 0.01 millimeters thick, and made of carbon nanotubes? Sagittarian Milky Way (talk) 18:07, 26 June 2012 (UTC)
- Acme Corporation should have those in stock. ←Baseball Bugs What's up, Doc? carrots→ 19:55, 27 June 2012 (UTC)
- It's easy. You just put some big old springs on it. There are some disadvantages to that approach, though, including an increase in the likelihood of hurting yourself. Looie496 (talk) 18:14, 26 June 2012 (UTC)
- Oscar Pistorius would say yes. But the fitting process is a big problem... SemanticMantis (talk) 18:15, 26 June 2012 (UTC)
- In addition to adding springs to change the impact energy (normally turned into heat) into kinetic energy, sneakers can also help you run faster by protecting you from injury. Somebody less afraid of injury will run less timidly, and somebody uninjured will also run faster. Sneakers also can get better traction on slick surfaces.
- On the other hand, sneakers can keep your feet warm and moist, which is an ideal breeding ground for various nasties, which can reduce your running speed. And then there's the extra weight carried around (and accelerated then decelerated with every step). So, well-designed running shoes, which fit properly, likely increase your running speed, while cheap sneakers may even make it worse. StuRat (talk) 18:22, 26 June 2012 (UTC)
- As I sit here on hold for Blockbuster Video's through the mail service, let me speculate that a good pair of well fitting sneakers will allow you to run your best (if not faster) while bad shoes will slow you down compared to bare feet. μηδείς (talk) 00:38, 27 June 2012 (UTC)
- I sure I wish I had thought to say that right before you did. :-) StuRat (talk) 02:03, 27 June 2012 (UTC)
- So you are about to cancel your through-the-mail account with Blockbuster as well? I have never been so disappointed. After I waited a week for it the first time, then drove it to the store to hand it in with a complaint to the clerk, they sent me the same cracked DVD a second time in a row! μηδείς (talk) 03:11, 27 June 2012 (UTC)
- I have Netflix, but dropped the DVD delivery when they upped the price, and now watch streaming only. StuRat (talk) 07:17, 29 June 2012 (UTC)
- I'd consider that but my computer chair is way less comfy than my TV chair. —Tamfang (talk) 06:06, 1 July 2012 (UTC)
- I have Netflix, but dropped the DVD delivery when they upped the price, and now watch streaming only. StuRat (talk) 07:17, 29 June 2012 (UTC)
The OP must not have seen the ads for PF Flyers in the 1960s. :-) Bubba73 You talkin' to me? 03:03, 27 June 2012 (UTC)
http://www.rockcreek.com/vibram/flow-mens/13215.rc Count Iblis (talk) 19:25, 27 June 2012 (UTC)
- This would be a fine question for the computer who wore tennis shoes. Clarityfiend (talk) 22:01, 27 June 2012 (UTC)
Rectal Swab vs Stool Test
[edit]Hello. When might a doctor order a rectal swab over a stool test? The stool test, where the patient defecates into a bag, seems more comfortable than the rectal swab, where the patient picks his rectum with a stick. Thanks in advance. --Mayfare (talk) 18:18, 26 June 2012 (UTC)
- The rectal swab would provide more of a local test, while the stool sample is more of a general test of the entire digestive system. So, the rectal swab might be useful if a rectal problem is suspected (like a tear in the lining which then became infected). StuRat (talk) 18:30, 26 June 2012 (UTC)
- That's not correct. First of all, a swab is a lot easier to collect than a stool sample. It's fine for detecting bacterial infections like salmonella where only a tiny sample is needed. Stool samples are needed to detect parasites, though, and usually more than one sampling is needed because the concentration of parasites is often low and they are relatively difficult to detect. The third type of test would be the test for occult blood, which requires a sample about the size of a BB. It detects bleeding anywhere in the GI tract, either from cancer or from a bleeding ulcer. Dominus Vobisdu (talk) 18:53, 26 June 2012 (UTC)
- Did you say anything that conflicts with what I said ? StuRat (talk) 19:56, 26 June 2012 (UTC)
- Yes. The swab does not detect localized problems, but problems with the entire digestive tract, just like the stool sample does. The difference is the kind of pathogen being tested for, with swabs working well enough with bacteria, fungi and viruses, and (multiple) stool samples being necessary for parasites.
- One exception is the "scotch tape prep" for pinworms. This involves folding a two inch length of scotch tape over on itself sticky side out, sticking one side to a tongue depressor (or spoon), then sneaking into the sleeping victims room with a flashlight at about 5 am, yanking the covers off, pulling their shorts down, and touching the sticky tape firmly to the skin around their their bunghole all with lightening speed. In the lab, the tape is examinined under the microscope for pinworm eggs. The worm crawls out the butt at night and lays them there in large numbers. Dominus Vobisdu (talk) 21:44, 26 June 2012 (UTC)
- Certain medical tests are meant as discouragements to would-be patients, of course. μηδείς (talk) 03:55, 27 June 2012 (UTC)
- ...and even more of a discouragement to nurses and interns. StuRat (talk) 03:59, 27 June 2012 (UTC)
Sodium fuel
[edit]Since sodium, as with other alkali metals, are so reactive, even to water, can we use them like gasoline (in the same way gasoline combusts) as a fuel source for cars? 64.229.5.242 (talk) 20:31, 26 June 2012 (UTC)
- There are probably ways that energy could be harnessed from pure sodium. But it is unlikely that there would be a safe and efficient system for doing so, and the production of pure sodium would require much more energy than you will get out of it (sodium metal does not exist in nature, so energy would be required to convert available sodium cations to sodium metal). — Preceding unsigned comment added by 148.177.1.210 (talk) 20:34, 26 June 2012 (UTC)
- Agreed. Also, if you react it with water you get a salt, which is rather corrosive, and shouldn't be released into the environment in quantity or it will kill the plants by the roads and the fish in the rivers where it ends up. StuRat (talk) 20:51, 26 June 2012 (UTC)
- It's a salt but not NaCl, there's no chlorine. Hot sodium hydroxide and hydrogen maybe? Ech, even worse effluent. You could melt human flesh with that. Sagittarian Milky Way (talk) 21:42, 26 June 2012 (UTC)
- Or clean your car. :) Matt Deres (talk) 22:10, 26 June 2012 (UTC)
- Well it would be far more efficient to using it in a sodium battery as efficiency may be over 50% rather than a chemical reaction making heat. The above water reaction would produce hydrogen, and probably in a more compact and efficient storage form than those liquid hydrogen fueled cars.
- Sodium metal, while very malleable, isn't a liquid. It would therefore be difficult to meter precisely. There are also logistical problems of refueling without causing an explosion; providing a transport mechanism from your fuel reserve to the engine; and transporting large quantities of sodium to fuel stations around the country/world . Also because it is so reactive, if any water got into your tank, boom. A little water in your gas tank is not really a problem. Gasoline is a much more stable fuel. Mythbusters tried a similar experiment with gun powder, they were unable to get it to work. Bcr666 (talk) 16:08, 1 June 2018 (UTC)