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

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June 20

Abnormal Color Correlations due to Psychological "illness"

Most people can agree that red symbolizes anger, evil, or passion. But others can disagree. Anger, evil, or passion can be more purple (or any other color) to them. Whether it's because of psychological illnesses, or it being normal, what can that say about the person? Also, people like to correlate their emotions with colors, but what do psychopaths see? Any help with explanations or links provided will be very much appreciated. Ive been looking for an hour and cant find a good answer. PitchBlack 02:31, 20 June 2007 (UTC)

We happen to have an article on Color symbolism and psychology, although this might contain some unknown amount of original research. But anyway, the mere fact that color correlations vary from culture to culture suggests to me that there is no greater meaning behind it. Someguy1221 03:13, 20 June 2007 (UTC)

I saw that link already. Didnt help. But thanks anyway for the contribution. PitchBlack 03:51, 20 June 2007 (UTC)

Even the definition of a colors can be a bit iffy, for instance grue, but associating a particular sound with a given shape in the bouba/kiki test appears to be nigh universal across cultures for people not on the autistic spectrum. -Eldereft 08:03, 21 June 2007 (UTC)

Wow that bouba/kiki thing is ridiculously interesting, thanks for the link! 213.48.15.234 08:24, 21 June 2007 (UTC)

Er, and article please? :)

http://www.sciencemag.org/cgi/content/full/316/5831/1558 I would be very happy if I could read this paper, but it costs ten dollars if I wanted to have it for one day, and I couldn't spend ten dollars on every article I wanted to read. If you're at an academic institution, would you please email it to me? I will give you my email address for any takers. Thanks, Mac [Mac Δαvιs] ❖ 04:10, 20 June 2007 (UTC)

Sciencemag is not the same thing as wikipedia - everthing on wikpedia is free to read. Are you complainging about a link from wikipedia? If the link is in the references section, this is what the author used to create the information in the article, so it can be fair enough to include them, but if someone finds a free source or good further information - this too can go in the atricle. GB 06:31, 20 June 2007 (UTC)

I'll send you a copy if you promise not to distribute it to anyone else. (I mean, you can read it for free at a library, so I don't see what the big deal is.) However, when I try to email you, I get "This user has not specified a valid e-mail address, or has chosen not to receive e-mail from other users." —Keenan Pepper 07:04, 20 June 2007 (UTC)

It is a major annoyance that you as a citizen have to pay to read an article on the results of science that might have been funded with your tax money, and I hope that the shift to open access journals will soon end this nonsense. Still, any good public library, and any university librtary usually has subscribed to the print edition and maybe the online archive of Science. You can still go there. Simon A. 08:30, 20 June 2007 (UTC)

Most public libraries will have copies of this magazine. Libraries are funded by the government exactly to mitigate the financial barrier to information; but free information isn't necessarily free information. Please do not use the Science Reference desk to expressly violate the license of copyrighted material. It will give us a bad reputation. Nimur 16:22, 20 June 2007 (UTC)

Bare Necessities Only for Survival

If a woman removed herself from any human contact for one year and stayed in an empty log-house in the woods (with no electricty and running water), what would be the absolute bare necessities (in detail) she would need to survive for one year? Also, the log-house is in walking distance to a big stream.

Obviously, you then HAVE running water. Necessities depend upon the environment, what the nature can provide. With water nearby, perhaps also flora yielding berries and similar, she can cover her nutritional demands. Assuming she can make use of rocks, she can cut out traps in different sorts, perhaps to hunt game. If not, there might be fish in the river, and it is not difficult to erect fish-fences to 'herd' fish closer to the shore, where they are relatively easy pickings. I imagine the climate is the most important factor, demanding or not demanding that clothes must be worn. If so, it is preferable that wildlife such as hares, deer or similar is close. In short, she doesn't need anything besides a suitable environment. If not, obviously the answer would depend greatly. 81.93.102.185 13:10, 20 June 2007 (UTC)

It all depends how much work you want to do and in what way. For example, you might regard a years worth of canned/dried food to be a necessity - or you might regard hunting as a part of this, so you'd want guns, fishing rods, traps, snares, etc - but you might be able to make stone tools and use those to make bow & arrows, spear, etc - and do even that part yourself. So I suppose the absolute barest minimum is nothing. You can make stone tools with stuff you find locally, use those to make hunting equipment, go hunting for food. But again, even that depends on where you are (a log-cabin in the middle of a rain forest would be a different prospect than one in the backwoods of Alaska. Are there suitable rocks present for making tools? Whether you could reasonably hunt for food in those places also depends on the persons' skills. It's no use assuming you'd make your own stone tools if you don't have the skills to do so. It's no use assuming you'd be able to hunt (say) deer - if you don't want to have to deal with the messy business of killing, gutting, butchering, cooking and preserving the meat. Can you start your own fire - do you know how? If you havn't thought much about this, you might want to read the classic children's books 'Hatchet' and 'Brian's Winter' by Gary Paulsen - they are (in my opinion) a bit optimistic - but they basically describe starting off life in the woods with a tiny pack of emergency supplies and a hatchet and nothing else.

Another children's book dealing with this topic is My Side of the Mountain. --LarryMac | Talk 13:21, 20 June 2007 (UTC)

But if you are hoping for a more relaxed existance - then it all comes down to what you want to do and the skills you have in order to do it. SteveBaker 13:14, 20 June 2007 (UTC)

A similar question was asked a couple of months ago and the responses are somewhere in the archives.You don't mention what your experience and capabilities are. This would help determine whether you could live like Tarzan or whether you would need lots of things packed in to your cabin. You might wish to try it for a week and then you would know lots more than you could ever envision a priori. Mother Earth News is a "back to the land" magazine which has 30 years of articles viewable online at [1]. If a person were removed from human contact, any injury or illness might be fatal, so it does not seem like a safe course of action. Survival experts have said that lack of air can kill you in 3 minutes, lack of shelter in 3 hours, lack of water in 3 days and lack of food in 3 weeks. Air is a given, and the cabin can furnish shelter if it is tight and well chinked and has a heat source for the winter, and the stream might be a water source if the water is or can be made safe to drink. Camping stores have water purification devices which could take care of drinking water. That leaves food as the big open question. Many of the Jamestown settlers in the 1600's starved, and the Unabomber in his cabin practically starved, so some things never change. Do you plan to hunt/trap/fish/farm/forage? Otherwise you would need to store a years supply of food, and have a means of cooking. You said no electricity, but that does not prevent a propane tank for heat or an oil tank depending on what part of the country. If wood is to be the heat source, then that could mean several cords of wood, which is a lot of sawing, hauling and stacking. Fireplaces are not very practical, at 10% efficiency or less, so an efficient woodburning stove would be more practical. A wood stove can be used for cooking as well as heating. Many houses are burned down by wood burning stoves: it is essential that there be a fireproof plate under it and that the chimnet have suitable protection where it penetrates the roof, and perhaps something fireproof between the stove and the wall. Do you plan on having some means of protection from predators (human and animal?) You may have chosen to shut yourself away from society, but the locals tend to know who is living where. Even though removed from human contact, it is a great idea to be on good terms with the neighbors. You might add to your reading list "Living the Good Life: How to Live Sanely and Simply in a Troubled World " by Scott Nearing and Walden by Henry David Thoreau. Keeping a journal like Thoreau would be a good idea. A dog and cat might be a good idea to provide companionship and deal with critters. I would want a big box of second hand paperbacks. (I suppose a solar panel and an internet connection to Wikipedia are out of the question?) Do you like sitting in the dark when the sun goes down? If not, lay in a supply of candles or perhaps a kerosene lamp and a lantern and a supply of fuel. Ample toilet paper would be something you would thank yourself for taking. First aid kit, lots of bug spray. Expecting to make stone tools without ever having done so, then using them to kill deer is pretty funny, as is starting a fire by rubbing sticks together. Recipe for starvation, unless one is an experience hunter/fisher/trapper. Edison 13:19, 20 June 2007 (UTC)

I meant to phrase my question if the woman isolated herself, in terms of supplies (that you can buy in any store), what is the minimum necessities she will need (in terms of nutrition).

Depending on the level of activity, between 1600 and 2500 calories a day, and 1.5 litres of water. Adequate calories doesn't mean adequate nutrition, so either a nutritionally balanced diet to ensure adequate vitamins and minerals, or a vitamin supplement. As for 'detail', there are lots of foods that would qualify, what do you like to eat, and how much storage space will you have? Anchoress 15:50, 20 June 2007 (UTC)

If the goal is to live away from humans, it might be easier to engage in a moderately successful rural career, such as ranching. You will still have some human contact, but your risks will be significantly lower. Nimur 16:32, 20 June 2007 (UTC)

It might be less painful to live away from other humans in a cabin in the Big Black Woods of the imagination than to live away from other people while working at a meaningless job and living alone in a studio apartment in the city without friends.

I have been amazed at how, even when you seem to be totally isolated in a cabin in the woods, people somehow know when you are away from the place for a couple of hours and break in and steal everything potentially useful. The country can be like a small town, in that everyone knows all about every one else's business. You should allow for some means of resupply in case people or animals destroy your supplies of steal your tools. Storage containers need to be resistant to animals. Mice will chew their way into and spoil anything in cardboard and perhaps plastic, and ants find their way into many containers. Metal containers or heavy plastic might survive better. Lots of canned food has a shelf life of over a year. Not so for eggs, butter, or fresh milk. Canned milk can be stored to last the year. Will the person be at the site all day every day without exception to keep the fire going? Need to keep the cabin above freezing to avoid the cans bursting. If it can't be kept above freezing, then dried food will serve: raisins, other dried fruit; powdered milk. Seems like beef jerky and Slim Jims would get tiresome in way less than a year. Dried beans, rice, flour, cornmeal and mixes for hotbreads, shortening and cooking oil, lots of Bisquick, lots of peanut butter and jelly, some Velveeta (refrigeration not needed until opened) and crackers. Yum! The amount of food needed depends on the amount of work done. If the hermit is clearing brush and trees from a planned garden and felling trees, sawing them up , splitting the pieces into firewood, more food is needed than if she is sitting around.(Be careful with the ax, because if it bounces off the wood and goes into your shin, you die a miserable death of gangrene. No human contact, remember?) If someone is just sitting in a cabin, boredom is likely to arise as a problem, leading to recreational eating, leading to the food not lasting as long as expected. This was even a problem in the space station, where they had other people and lots to do. Laundry? Get yourself a washtub [2] and Washboard. Sanitation? Chamber pot and a hole in the ground with a pile of dirt to cover each days waste. The ambitious can find plans for a deluxe Outhouse in Mother Earth News. Figure on a couple of days work just digging the hole in the ground for the outhouse, what with rocks and tree roots. I would definitely put in a garden, but not be wholly dependent on it to feed me over the winter, because I have seen what drought, hail and deer can do. This style of living is not far from what I have done in an old cabin for a couple of weeks at a time, and called it a vacation! Tools to do the things mentioned: ax, hatchet, crosscut saw, hammer, nails, shovel, pickax, hoe, garden rake, Swiss army knife or equivalen multitool, flashlight and spare alkaline batteries/bulb. Screenwire for windows. Rocking chair for front porch. Flower and plant seeds and garden fertilizer. Matches in waterproof container. Lots of detergent. Bug spray. Insect repellent. Another good series of books is the Foxfire series, as well as the Boy Scout Handbook (some of the editions from recent decades have less about wilderness survival and more about urban living. Check used book stores). or equivalen GirlScout manuals. Take a look at the 2005 USDA food guidelines [3] , Nutrition , Nutrient , Homesteading , Back to the land , Survivalism , Smallholding , and Simple living . Country people lived basically like this in my grandparents time (except for the proposed lack of human contact) and many did just fine. Edison 16:56, 20 June 2007 (UTC)

Thanks everyone for all of your great input! I was having a hypothetical conversation with a friend and wondered if, on a dare only, what would be the base necessities a woman needed if she isolates herself in the woods. She mentioned chocolate and feminine products!

Pioneer women managed without chocolate. Wild berries can also be tasty. A TV series on pioneer life on public TV said that pioneer women used cloths held by a belt (like a breechclout) when they had their period, then washed them for future use. Oh, I forgot shampoo and conditioner. The lack thereof was a big concern for the neo-pioneer women. If I were stocking a cabin for one year, for one person, I would figure 2 pounds of food a day. If it were pure carbohydrate or protein, one grams equals four calorie, (and 9 calories per gram of fat) so 2000 calories of protein/carb equals 500 grams, or about a pound. The other allowance would cover packaging, cooking supplies, etc. Then the water, if brought in would need to be about 3 pounds a day for drinking. You could assume she hires someone with an off-road four wheeler (or packmules) to drive the supplies in to the cabin (trust me, they will go about anywhere there is a cabin). Edison 17:38, 20 June 2007 (UTC)

If you are planning to live on stored food - you could do worse than to look into the military MRE's. I've eaten a few of them and they aren't too terrible (although the guys in the military *LOVE* to complain about them). You can reconstitute (and even heat them!) just by adding cold water. They last forever without refrigeration - they can be left outdoors in desert sun or arctic cold without harm. They are carefully designed to be nutritionally balanced - so you can live on nothing else for a very long time without suffering nutritional problems and there are a couple of dozen varieties, so you could go for a week or more without eating the same meal twice. You can buy them on eBay - they seem to be selling for between $3 and $10 per meal - figure two meals per day plus some spares - 356 days in the cabin - about $3,000 maybe. You'd need vermin-proof storage - but you could store all you need in something like a disused chest freezer (not plugged in!). I think that you could certainly plan to eat a significant fraction of your diet this way - by all means take special treats to break the monotony. They come in several kinds - for example, there are special cold weather versions which have vastly more calories. If you planned to do that - you should certainly buy a couple of weeks worth and practice eating nothing else just to be sure you could cope with them - but it's a very safe option - you know you aren't going to die from the lack of some obscure vitamin or mineral - you know they won't rot - you can heat them without having to gather wood - so if you get sick and can't go out - you'll be fine so long as you have plenty of water. They include other necessities like toilet paper and matches that might also come in handy. SteveBaker 19:44, 21 June 2007 (UTC)

Muscles

Could some one tell me the adaptations taking place when you keep a muscle tense for long periods? For example you can take a person holding a handgun. No story here guys, I just wanted to know what does the body do to be able to sustain longer periods in tense positions. Bastard Soap 12:33, 20 June 2007 (UTC)

Backstory: Same question was asked here on the 16th, didnt get much of an answer. 213.48.15.234 13:12, 20 June 2007 (UTC)

Yep I know, I'm trying my luck again mac.

Actually, I'm a PC. 213.48.15.234 13:36, 20 June 2007 (UTC)

You are attempting to answer a reference desk question, cancel or allow? --LarryMac | Talk 18:32, 20 June 2007 (UTC)

"attempting" 213.48.15.234 07:06, 21 June 2007 (UTC)

I'd suggest checking out this paper: different pools of muscle fibers seem to trade off in holding the position, a synergy that seemingly allows some amount of rest to occur in fibers during a long-term, low-level fatiguing task. — Scientizzle 16:06, 20 June 2007 (UTC)

antibiotics

tell alternative antibiotics in place of cycloheximide/nystatin/rifamycin/polymixin 12:35, 20 June 2007 (UTC)Atiniv

This sounds like either homework or a request for medical advice, neither of which we handle here. Confusing Manifestation 13:41, 20 June 2007 (UTC)

The proper alternative would depend on what type of bacteria you intend to target with it, and what allergies the patient has or might have, and what other drugs they are or might be on, and finally you'd need to ask a doctor to find the answer. Someguy1221 23:42, 20 June 2007 (UTC)

Soda expiration date

This soda went past its expiration date on June 15th. What chemical reactions lead to the worsening in quality of sodas such as this (it's orange-flavoured, by the way), are they perhaps potentially toxic after a certain amount of time? 81.93.102.185 13:20, 20 June 2007 (UTC)

I'm just as concerned about Sodium benzoate and its effects regardless of the expiry date. iames 13:42, 20 June 2007 (UTC)

There's even an article, I see: Benzene in soft drinks. iames 13:45, 20 June 2007 (UTC)

The two main effects on soda in plastic bottles are plasticizers from the bottle leaching into the drink and the loss of carbonation (going flat) due to CO₂ leaching out through the plastic. Keeping soda in a cold, dark place will slow, but not eliminate, both processes. Soda in cans or glass bottles should do much better. StuRat 17:54, 20 June 2007 (UTC)

Generally, the expiration date on foods refers to quality, rather than toxicity. For instance, botulism in canned foods; the expiration date doesn't represent some kind of break point where before that you don't have to worry about botulism and afterwards you do. In sodas, and I'm guessing here, it's probably the flavor compounds aging/reacting/breaking down more than anything, with a side issue of CO2 escaping slowly so it gets flat. Probably reduced if it's kept in the dark, but again I'm guessing.Gzuckier 18:27, 20 June 2007 (UTC)

Raising HDL

I've always had extremely low HDL levels. I know there are a lot of drugs for lowering LDL levels. Are there drugs specifically for raising HDL levels? --Kainaw ^(talk) 15:09, 20 June 2007 (UTC)

This link recommends niacin (at prescription doses) as statins are poor HDL raisers (but good LDL lowerers)... — Scientizzle 15:56, 20 June 2007 (UTC)

Hmm. Niacin is usually described as acting chiefly on triglycerides, with little effect on HDL-C. Some of the statins, including simvastatin and rosuvastatin have some mild HDL-C increasing effects, somewhere in the 10% range. Efforts have been underway for quite some time (early 1990s) at making a specific HDL-C-increasing drug. The CETP-inhibitor torcetrapib looked promising until a clinical trial seemed to suggest it increased mortality. Cheers, David Iberri (talk) 16:29, 20 June 2007 (UTC)

Whoops; apparently niacin's effects on HDL-C are weak compared to its activity on triglycerides, but its HDL-C-lowering activity is still significant (15-35%). This is from class notes, but I'll see if I can dig up a reference. --David Iberri (talk) 16:35, 20 June 2007 (UTC)

Also, why not change your diet to improve this ? Try eating more walnuts and salmon, for example. StuRat 20:39, 20 June 2007 (UTC)

Or for that matter, exercise. But I assumed Kainaw had already read HDL and figured that out for her/himself and was just interested in pharmacological interventions for a specific dyslipidemia. --David Iberri (talk) 00:02, 21 June 2007 (UTC)

In western nations, people are far too dependent on drugs with potentially dangerous side effects to fix conditions which can easily be remedied with diet and exercise (both of which have potentially wonderful side effects), and people should be reminded of those options at every opportunity, IMHO. StuRat 04:43, 21 June 2007 (UTC)

gasoline

About how much does a gallon of "regular" gasoline weigh? (Barry, June 20, 2007)

Six pounds, IIRC. Less than water, obviously, and a gallon of water is 8 pints therefore 8 pounds. In the US only. Of course, in formula one racing a few decades ago where they ruled how many liters of fuel a car could use, they would concoct these incredibly dense blends of "gasoline" full of benzene and such that were actually heavier than water in order to maximize the energy they could carry in that limited amount of volume.Gzuckier 18:52, 20 June 2007 (UTC)

Check out Gasoline#Energy_content. They have the approximate density there. David D. (Talk) 18:55, 20 June 2007 (UTC)

• Per the above, @ 60° F, gasoline weighs 737.22 kg/L, and thus - in U.S. gallons:

${\frac {737.22kg}{m^{3}}}*{\frac {1m^{3}}{1000L}}*{\frac {3.785L}{1gal}}*{\frac {2.205lb}{1kg}}={\frac {6.153lb}{gal}}$

Of course, YMMV.... -- MarcoTolo 19:36, 20 June 2007 (UTC)

On a related subject, what's the coefficient of thermal expansion? Would going from a 50F environment to a 100F environment cause the gas to expand enough for an apparent 20% increase in fuel economy? --Carnildo 21:49, 20 June 2007 (UTC)

It would actually be a decrease in fuel economy (expansion results in less energy per volume). No idea if it would approach 20% or not, however. — Lomn 21:56, 20 June 2007 (UTC)

Depends on how you measure it. If you fill a gas tank with high-density gas at 50F, burn off some of it travelling to the 100F environment, then measure the remaining volume of now-low-density gas, you'll appear to have burned less gas than you actually did. --Carnildo 21:29, 21 June 2007 (UTC)

Be careful - US gallons or rest-of-world gallons? SteveBaker 22:45, 20 June 2007 (UTC)

• Well, I did say "You Mileage May Vary" <grin>, but for Imperial gallons:

${\frac {737.22kg}{m^{3}}}*{\frac {1m^{3}}{1000L}}*{\frac {4.546L}{1gal(Imp.)}}*{\frac {2.205lb}{1kg}}={\frac {7.340lb}{gal(Imp.)}}$

-- MarcoTolo 19:49, 21 June 2007 (UTC)

name that rock

OK, in my nerdy youth i was a little rockhound, but this has me stumped. I live in a swampy part of New Haven CT, where if you dig down a foot or two anywhere you hit some dense red clay. I dont' know if this is the same red clay as in GA or somewhere. Sometimes it smells sulfrous. Anyway, in this red clay, there are various lumps of varying density, some you can squeeze apart, some hard enough that I would classify as 'rocks', which certainly appear to be clay on its way to becoming sedimentary rock. The hardest pieces really resemble chunks of brick, though, to the point where if there weren't the intermediate densities, i wouldn't be so sure they weren't actually just old chunks of brick buried in the clay. Anyway, that sure doesn't seem like any kind of shale i ever encountered as a kid, as it's not layered at all, just amorphous. What kind of rock would this be, or does it get classed as rock at all? What kind will if be then, if it ever evolves to rockhood, as it sure doesn't seem headed in a shalish direction. Gzuckier 18:56, 20 June 2007 (UTC)

I would speculate that the clay was once at the surface, and the water receded, allowing the clay to be baked in the sun. Thus, you have broken up pieces of clay brick mixed in with the clay. A geologist should be able to provide us with a better term for it. StuRat 20:36, 20 June 2007 (UTC)

New Haven CT is underlain largely by Triassic red beds, shales and mudstones that were deposited under conditions that allowed the tiny amounts of iron in the sediment to oxidize, making the rocks red. The clay you have found may be essentially a soil derived from those rocks, and the chunks within the clay may be more indurated (less fragmented, less eroded) pieces of the same material. Shale and mudstone are the same thing - rocks derived from mud-sized particles - with shale having fine-scale layering and mudstone having none. Sounds like what you have are pieces of mudstone. The "shalish direction" develops in clay and mud materials as burial squeezes water out and compresses the tiny grains into flat orientations - and simultaneously can produce the thin layers common in shale. So thin layers typical of shale rock might not be typical of the unconsolidated or partly consolidated sediment - it all depends on the material, and its burial history. Cheers Geologyguy 23:38, 20 June 2007 (UTC)

Thanks. Gee, when I was a young science nerd, I never had any idea this even existed. Gzuckier 17:10, 21 June 2007 (UTC)

Real hospitals vs. the hospital shown on House MD

There was another thread about House MD a while back but I can't find it now. In it, I think someone mentioned that in real hospitals, unlike the hospital in the show, there is no such thing as a 'Department of Diagnostic Medicine' or specialist 'Diagnosticians'. Is that true? --84.68.75.89 19:53, 20 June 2007 (UTC)

Googling the phrase shows some medical (and veterinary) schools and some teaching hospitals have such a department name. While googling "'Diagnosticians" finds the definition: "One who is skilled in making diagnoses; formerly, a name for specialists in internal medicine." Rmhermen 21:01, 20 June 2007 (UTC)

Caterpillar Food

I happened to find a large pregnant Antheraea polyphemus moth on the underside of my car and it has layed ten or so eggs in the large net/cage I have it in (though I was planning on letting it go before this happened). I was wondering what kind of plants the caterpillars eat, or even better is there some kind of supplemented food I can make for them myself. BeefJeaunt 20:00, 20 June 2007 (UTC)

Try giving it a variety of leaves and see which ones it eats, then give it more of those. StuRat 20:25, 20 June 2007 (UTC)

Looking this species up on the site Butterflies and Moths of North America, its larval food includes a number of shrubs and trees, including oak, willow, maple, walnut, elm, and birch.--Eriastrum 21:24, 20 June 2007 (UTC)

Eppy

When, it programs and dramas such as House mentioned above, ER, Scrubs and all that, they request two milligrams of "Eppy" are they refering to Epinephrine? SGGH ^speak! 20:10, 20 June 2007 (UTC)

Yes, I believe so. StuRat 20:23, 20 June 2007 (UTC)

Thanks SGGH ^speak! 20:28, 20 June 2007 (UTC)

Yup, that's what it is, although it's usually written as "epi", as in EpiPen. --David Iberri (talk) 01:39, 21 June 2007 (UTC)

OJ-cough hurting more than usual

When you get water/soda/anything in the wrong throat (hard to find words for it, but you know what I mean), you gotta cough, and it can be a nuisance. However, I just did the same with orange juice, and it's more than annoying - coughing is close to painful really. Can this be explained? 81.93.102.185 20:24, 20 June 2007 (UTC)

If orange juice goes down your trachea instead of esophagus, the citric acid is likely to cause acid burns. Try drinking and breathing more slowly. StuRat 20:27, 20 June 2007 (UTC)

Also if it is orange juice with "bits" in, the above factor will be increased, and the bits themselves could be an irritant? SGGH ^speak! 20:43, 20 June 2007 (UTC)

Oxy-liquid

I know that there is a heavily oxygenated liquid that humans (in theory) would be able to breath and that certainly rats and mice are able to breath, however what are the problems with humans breathing normal water? It does contain oxygen but is it simply not enough? Is no level of inactivity low enough to reduce the human bodies need for oxygen enough to survive in water, if just for a short time? Or is it more of a density issue aswell, with te lungs not being able to move such a dense liquid? SGGH ^speak! 20:52, 20 June 2007 (UTC)

Our liquid breathing article doesn't mention the oxygenation levels used, but breathing gas tells us that the effective pressure needs to be at least 0.16 atmosphere. I wonder how much one can cram into water, and whether having it "predissolved" affects the exchange rate with the blood (and hence that lower limit). DMacks 21:11, 20 June 2007 (UTC)

Apparently, humans would require roughly 970 sq. ft. (90.21 m²) of a hydrophobic artificial gill to provide enough oxygen for normal activity, as opposed to 75 m² area for a human lung. Atmospheric is roughly 21% concentration and whatever pressure the lungs sustain, reduced to 16% on exhalation. Getting oxygen into the alveoli is just passive diffusion, so barring further complications sufficiently oxygenated water ought to work. -Eldereft 09:00, 21 June 2007 (UTC)

Also, of course, it's more work to pump the water in and out, and it's much more likely to be incomplete and leave more of the water stagnant without changing it. That's already a factor with air. Gills being a flow through system helps a lot. All this, of course, is why there aren't any water-breathing warm-blooded animals, they can't get enough oxygen. Gzuckier 17:13, 21 June 2007 (UTC)

Uses of gas solutions

My teacher told me to get some uses of gas solutions so that the students in my class each get a topic and write and explain about it. So far I have: air used for transportation, recreation and breathing, anaesthetic for surgical operations and natural gas for many things. Can you please give me some gas solutions and their uses. It would be highly appriecated. And is steam a soulution?(My spelling is bad!) 74.113.188.65 21:42, 20 June 2007 (UTC)

Air is also used in pneumatics, such as a pneumatic tube. StuRat 22:14, 20 June 2007 (UTC)

Aren't they usually oil-filled? Also, does the gas solution of the air we breathe count? --Wirbelwindヴィルヴェルヴィント (talk) 22:17, 20 June 2007 (UTC)

Pneumatic by definition uses air (or some other gas) pressure. Maybe you're thinking hydraulic? DMacks 22:26, 20 June 2007 (UTC)

Pneumatics==Gas - air or something else, Hydraulics==Liquid - oil or water. SteveBaker 22:36, 20 June 2007 (UTC)

Oh right, silly me... --Wirbelwindヴィルヴェルヴィント (talk) 09:26, 21 June 2007 (UTC)

Air is obviously a solution of oxygen and nitrogen (plus some other stuff). Deep sea divers breathe all sorts of mixtures of oxygen with other gasses (See trimix and heliox and Breathing gas) in order to avoid nitrogen bubbles. Welders use oxy-fuels of various kinds. You might also want to check out Forming gas (Hydrogen+Nitrogen) - which has a number of odd-ball uses. There are lots of aneasthetics that are gas solutions...I'm sure there are a bunch more - but that'll do for now! SteveBaker 22:36, 20 June 2007 (UTC)

Acetylene in H₂ for diamond growth. And steam as gaseous water in air would qualify as a solution, yes. -Eldereft 09:11, 21 June 2007 (UTC)