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February 26[edit]

the ocean[edit]

What is a volcano called in the ocean? What are the low hills and plains in the ocean called? What causes waves to form?

--Shayshay789 (talk) 00:46, 26 February 2008 (UTC)shayshay789[reply]

Volcanoes in the ocean (as far as I have been told) are called volcanoes. Waves can form due to wind or seismic activity. (Waves formed by the latter are usually huge and are referred to as tsunamis.) This is as much as I know about this particular subject. Someone else, therefore, will probably be able to provide you with a more complete and detailed (perhaps corrected?) response. Hope this is of help, Zrs 12 (talk) 02:10, 26 February 2008 (UTC)[reply]

Wikipedia has some good articles about these, which would be a good place to start. Try Submarine volcano, and the very detailed Ocean surface wave and Tide articles. Gwinva (talk) 03:13, 26 February 2008 (UTC)[reply]

Abyssal plain is the name for the deep flat plains on the ocean floor. The flat bits that are shallow near the continents are Continental shelf parts. Hills may be Seamounts and could be cause by volcanoes, tectonic uplift around faults, or erosion. Graeme Bartlett (talk) 10:57, 26 February 2008 (UTC)[reply]

food processoring[edit]

I've noticed that my body does not always digest every particle of food I eat. Sometimes when I am in a hurry I've noticed even whole kernels of corn in my poop. To prevent this I've started using a food processor to break everything down into a paste. How much less food will I have to eat if it is pre-macerated in this way or how much and/or how many more nutrients will be absorbed by my gut? 71.100.9.94 (talk) 02:34, 26 February 2008 (UTC)[reply]

provided you chew the food processor shouldn't be neccessary —Preceding unsigned comment added by 83.100.138.74 (talk) 04:51, 26 February 2008 (UTC)[reply]

Many people do not live a slow backward life which allows them to consume a single meal over the course of 5 hours. Besides, anyone can still chew pre-macerated food if for only the purpose of adding enzymes found in saliva. However, that was not the question. The question is not whether it is necessary to pre-macerate food but rather the benefit - just like riding a bicycle is not necessary but to most offers a benefit. 71.100.9.94 (talk) 12:02, 26 February 2008 (UTC)[reply]

Wikipedia does not provide medical advice. If you are seriously concerned about this, please consult a nutritionist. Dforest (talk) 08:37, 26 February 2008 (UTC)[reply]

Why would I ask the Wikipedia for medical advice? Isn't it more logical that I would come to the Wikipedia to find a reference for studies that have been done on eating pre-macerated food? Why man the reference desk if you are too lazy to help find a reference? 71.100.9.94 (talk) 12:02, 26 February 2008 (UTC)[reply]

It's not a function of "laziness"; rather, it's more likely a recognition that we're not qualified to properly evaluate the merit of such studies that might be found. I don't personally think this is really a medical advice issue, but Dforest's point absolutely stands: if this is a matter of real concern, address it with your doctor. — Lomn 14:15, 26 February 2008 (UTC)[reply]

Nosense. He has no point, having wrongfully assumed medical advice was sought, ...and that is being generous. His response was for the purpose of showing you he was capable of upholding a rule that has no other purpose for application here. Even below he continues to relate this question and the answer to medicine while it is completely unrelated to anything except scientific biological studies to which medical researchers might refer but would not likely conduct.

Even if someone asks for medical advice you do not have to make an issue of Wikipedia policy as the answer but rather provide encyclopedic references so they might continue their research themselves. That is your job isn't it? Even in his response below after my telling him the question is not medically related he has cited a medical reference and not references of scientific studies which are not medically based. It is his mind set that is the problem and not how my question was phrased.

Aside from that he did not ask if I was seeking medical advice but made a wrongful assumption and then rudely cut me off. Now you are wrongfully coming to his rescue and defense rather than correcting him for the mistake of 1. making a false assumption and 2. not correcting his assumption and rather providing a reference which was not sought.

Actually, I'm "coming to his defense" because your conduct is lousy. Simply put, catering to your whims and your interpretation of Ref Desk guidelines is not my job nor anyone else's. I noted above that I was sympathetic to the merit of your question, but that does not mean I condone your insults towards respondents. — Lomn 14:17, 27 February 2008 (UTC)[reply]

Since you phrased your question in terms of a concern with your body it seemed as if you were looking for advice to medicate, or to change your diet. Hence the disclaimer. If you are looking for studies, PubMed is a good place to start. Dforest (talk) 22:49, 26 February 2008 (UTC)[reply]

I am not looking for medical studies. Having been so informed you now need to update your wrongfully assumed and false mindset.

Unfortunately I don't have a reply for your question, but, after reading it, the last thing that came to my mind was that you were looking for "medical advice"... --Taraborn (talk) 20:10, 27 February 2008 (UTC)[reply]

I suggested that only chewing should be neccessary because that's how it (the body) works - coverting the food to a fine pulp might help you to extract more, but may not be the best choice for digestion. —Preceding unsigned comment added by 87.102.42.162 (talk) 15:09, 26 February 2008 (UTC)[reply]

Regarding corn – my understanding is that the centre of the kernel is digested, but the bright yellow surrounding passes through essentially untouched. This may well be what you're seeing. Angus Lepper^{(T, C, D)} 18:57, 26 February 2008 (UTC)[reply]

Taigas[edit]

what are adaptations to animals in the taigas of the world? What are examples of symbiosis in these taigas? I have checked wiki already in their subject of taiga but there is nothing about symbiosis. —Preceding unsigned comment added by 203.148.171.10 (talk) 04:00, 26 February 2008 (UTC)[reply]

In the fauna section they mention that many of the animals have adapted to survive in a harsh climate. Adaptations such as hibernation and layered fur/feathers as well as the ineffeciency of carnivorous diet. I would suggest looking into some of the animals that are linked in that section if you want to see specific examples. -- MacAddct  1984 ^{(talk  contribs)} 04:21, 26 February 2008 (UTC)[reply]

Plugging both speakers in to one channel of a preamp[edit]

Hello, this is a pretty n00bish question so I'm sorry if the answer is painfully obvious. I have a preamp, but the left channel is busted (it's my dad's old Marantz preamp from the 70's - typical big old basement setup). My friend had the exact same situation and he told me to just plug both speakers in to the output of the channel that works, so since each channel has two little output clips and each cable coming from each speaker has two little copper wire ends, that would make two copper wire ends per clip....if that makes sense. I would be panning the sound completely to the right, and have both speakers hooked up to that channel. The preamp has a button that converts the signal to mono so I don't have to worry about losing sound from the left channel. Just wondering if they will be very underpowered? I'm bringing the preamp and both speakers to a party in a basement, and I intend on blasting some party classics pretty loud without damaging any equipment. Thanks a lot! NIRVANA2764 (talk) 04:06, 26 February 2008 (UTC)[reply]

Yep - you only get mono - not stereo - you're big worry is the resistance of the speakers - since the speakers are connected in parallel you are effectively having the resistance eg if your speakers are labelled 8ohms then the resistance combined is 4ohms - most amps have a minimum resistance they can use - check this and compare - if the resistance is too low you risk overheating the amplifier and potentially losing another channel..

ps in the uk 'preamps' are usually not amplified - there are pre/power combinations - I believe that in the us pre-amps are sometimes powered - bit confused about that.

If the resistance is too low connect the speakers in series as another option.

It all depends on the specs of your speakers and of the amp - suggest you supply these.

For safety just connect one speaker - unless the amp is much more powerful than the speakers need you wouldn't get much benefit from paralleling - if the amp is powerful then do it.83.100.138.74 (talk) 04:48, 26 February 2008 (UTC)[reply]

I concur you should do fine selecting mono to make sure the output includes bots stereo channels mixed together, then using only one speaker connected to the output that works. Enjoy! Edison (talk) 05:23, 26 February 2008 (UTC)[reply]

Nah. More speaker area is better. And if you don't want to bother about calculating impedances, you can't hurt anything by wiring the speakers in series: [Amp+...+...Speaker...-+...Speaker...-...Amp-]. A "preamp" does not have speaker outputs in any country; an "amp" or "amplifier" or "receiver" does. --Milkbreath (talk) 11:55, 26 February 2008 (UTC)[reply]

Assuming the output of the amp is 50 watts per channel into 8 ohms for each channel when normally connected to the speaker, and that it is a constant voltage output (that can certainly be debated). Now hook 2 speakers in series: the impedance of the load (speakers) doubles and the total output power from the one channel into the two speakers in series becomes only 25 watts.(Same voltage divided by twice the impedance). "More speaker area" may be wonderful, but with half the output power the volume is going to be quite a bit lower. If the amp somehow produces more like constant current then the voltage would have to increase to keep the volume constant. Edison (talk) 22:46, 26 February 2008 (UTC)[reply]

The power is 185watts, and both speakers are 8ohm. If I run them in series, then that doubles the resistance, and too much resistance sends the power back and fries the preamp. So is it even safe to run it in series??? NIRVANA2764 (talk) 21:38, 27 February 2008 (UTC)[reply]

Unidentified bathroom fly or moth[edit]

For several years now, I keep encountering this small insect in public restrooms, and recently, the bathrooms in my home. I see them only in bathrooms and nowhere else. They look like little flies with round bodies. The wingspan when "parked" is about 3mm from tip to tip. They fly silently without a discernible sound although their wings are a blur. They don't fly fast; they seem easily blown about by breezes, which may explain a preference in the relatively still air of a restroom.

I have no idea where they come from, or why I see them only in restrooms. I suspect they may come out of the drains, hatching from larvae attached to spaces in the pipes where they won't get washed away.

I've been seeing these for so many years, and finally got around to taking a photo of one, so I thought I'd ask here. If an article has been written about it, I certainly can't find it.

So, anyone know what insect this is? =Axlq 07:11, 26 February 2008 (UTC)[reply]

I have seen these little chaps but only in our bathroom in southern Spain. Can you provide some geographical location. Richard Avery (talk) 07:54, 26 February 2008 (UTC)[reply]

I am in the United States. I have seen these flies throughout the country (from Washington DC to San Francisco), and I recall seeing them in other countries as well. =Axlq 17:40, 27 February 2008 (UTC)[reply]

It's an adult Bathroom Fly (Drain Fly) Clogmia albipunctata (also: Telmatoscopus albipunctatus), Diptera: Psychodidae. Julia Rossi (talk) 08:22, 26 February 2008 (UTC)[reply]

Link: Bathroom Fly. —Lowellian (reply) 01:08, 27 February 2008 (UTC)[reply]

PS It's a beautiful double angle shot (complete with bathroom environment lighting) you might like to put it in the article. Julia Rossi (talk) 08:32, 26 February 2008 (UTC)[reply]

As I recognise myself in the above depiction of a barfly, I stress that a publication of the image will be met with my strongest objections. I feel it an intrusion of my private pa- oops, my private sphere if a photo of me rubbing my proboscis in the intimate environment of Axlq´s bathroom could be used by sundry psychos and didiae for their lustful debauchery. --Cookatoo.ergo.ZooM (talk) 21:32, 26 February 2008 (UTC)[reply]

Shoo. —Preceding unsigned comment added by Julia Rossi (talk • contribs) 21:59, 26 February 2008 (UTC)[reply]

I'm happy to add it to the Bathroom Fly article. And thanks User:Lowellian for adding a redirect for bathroom fly - my previous search for that term turned up with nothing, which led me to ask about it here. Years of wondering about this little bug have now been answered! Thanks! =Axlq 17:40, 27 February 2008 (UTC)[reply]

"Shut-in" oil production[edit]

What is 'shut-in'oil prodution? "The Nation's economy lost $45.49 Billion...in the last three years...to shut-in crude oil production in the troubled Niger Delta. The shut-in was occasioned by the activities of militants...(Nigerian newspaper Vanguard). Thanks if you can explain. —Preceding unsigned comment added by 83.229.85.138 (talk) 10:32, 26 February 2008 (UTC)[reply]

From a look around it looks like it means production from wells that have previously been 'shut in' (i.e. had the entrance filled). I guess this much based on the following paragraph in an article "Thus, last week's seemingly hefty price was just 20 cents a barrel more than last January, and until the future is clearer, L.A. oilmen are not rushing out to uncap and resume production from shut-in wells. West Coast crude oil stocks remained above the lofty 80-million-barrels mark, according to American Petroleum Institute figures: a towering 86.6 million barrels as of Aug. 10.5 percent above the 78.34 million of a year earlier." (http://findarticles.com/p/articles/mi_m5072/is_n33_v13/ai_9395087). ny156uk (talk) 18:34, 26 February 2008 (UTC)[reply]

A shut-in well is temporarily "closed" or blocked from production. It can be re-opened. In contrast, a well that is plugged and abandoned cannot be re-opened without considerable difficulty. Cheers Geologyguy (talk) 03:39, 27 February 2008 (UTC)[reply]

knee surgery[edit]

what is involved in a full knee reconstruction? —Preceding unsigned comment added by 81.139.65.131 (talk) 10:35, 26 February 2008 (UTC)[reply]

Take a look at knee reconstruction, but we cannot give medical advice. Graeme Bartlett (talk) 10:59, 26 February 2008 (UTC)[reply]

Does hand sanitizer kill viruses?[edit]

The cold virus for example. Also, does alcohol kill viruses? 64.236.121.129 (talk) 18:12, 26 February 2008 (UTC)[reply]

See alcohol rub: "Alcohol rubs kill many different kinds of bacteria, including antibiotic resistant bacteria and TB bacteria. Alcohol rubs inactivate many different kinds of viruses, including the flu virus and the common cold virus. Alcohol rubs also kill fungus." -- MacAddct  1984 ^{(talk  contribs)} 19:21, 26 February 2008 (UTC)[reply]

It also depends on whether or not the virus posseses a lipid envelope. Viruses that do are more susceptible to antiseptics such as ethanol and acetone as they permeabilize the lipid. Wisdom89 _{(_T / ^C)} 19:24, 26 February 2008 (UTC)[reply]

Can hand sanitizers breed resistant mutants like antibiotics do?128.163.174.150 (talk) 23:57, 26 February 2008 (UTC)[reply]

In my opinion, it's possible in the sense that anything with evolution is possible if you give it enough time. But I don't believe there are any cases of this occuring. 64.236.121.129 (talk) 14:28, 27 February 2008 (UTC)[reply]

Alcohol-based hand sanitizers evaporate quickly, i believe this is why they don't allow for resistance to evolve in the affected organisms.Horia (talk) 05:17, 28 February 2008 (UTC)[reply]

SRS statistics[edit]

Which direction of sex reassignment surgery is more common - male to female or female to male? (The answer is probably obvious, but I'd still like to be sure.) - Sikon (talk) 18:13, 26 February 2008 (UTC)[reply]

We have a section on this: Transsexualism#Prevalence. (EhJJ)^TALK 23:12, 26 February 2008 (UTC)[reply]

Harmonics (?) with RF emissions causing lights to go out[edit]

Recently I saw a demonstration of a radio transmitting on HF causing flourescent light tubes to dim and, at one frequency, turn off altogether. I am not sure if a similar effect was seen on mains powered devices. I am attempting to reproduce this behaviour... does anyone have any tips as to what the correct frequency might be or how much power output I would need? Thanks, Martinp23 19:31, 26 February 2008 (UTC)[reply]

I discovered today that a freq. of 5 Mhz (and many others presumably) with output of 30W would cause a light tube held to the antenna to light up. Any ideas as to my original question? Martinp23 17:52, 27 February 2008 (UTC)[reply]

The rareified gas in a fluorescent lamp (which is a pretty good article) will ionize in the presence of any oscillating electric field. If you go out on a dark night and hold a fluorescent tube under a high-voltage electrical transmission line (like these), it will light up. Also, if you touch a fluorescent tube in a dark room with a static charge built up on your body, the tube will dimly illuminate from the electrons discharging from your body into it.

Because the fluorescent tubes are illuminated via an oscillating field, another electric field source tuned at the same frequency and phased to cancel the field inside the lamp, should dim it. I'd say a strong 60 Hz field (or a harmonic frequency) would do the job for household lights. =Axlq 18:14, 27 February 2008 (UTC)[reply]

My first guess is that the frequency (5 MHz) is not special, except that it's convenient to generate and transmit wirelessly. As you can plainly observe, 60 Hz will also light up the tube (when connected via household AC wiring), but 60Hz does not transmit very well as a wireless signal from a handheld unit (the antenna required would be huge). Nimur (talk) 23:14, 27 February 2008 (UTC)[reply]

Engineering(Naval Arts) - detrimental effects on ship cause by twisting propulsion engines[edit]

Example :

A ship have 2 propulsion engines on individual throttle(which means you could control each engine by it's own throttle) are at different speed and direction. One of the engine is at half ahead(half forward thrust), while another is on full astern(full backward thrust). This action is called twisting.

Information :

1.) There are a lots of stresses on the ship's hull. 2.) Vibration

My questions :

1.) What are the bad effects on the ship? 2.) The damages that this action(twisting of engines) could caused?

Thanks Boonyuan (talk) 19:52, 26 February 2008 (UTC)—Preceding unsigned comment added by Boonyuan (talk • contribs) 19:49, 26 February 2008 (UTC)[reply]

It seems that you've basically answered your own question -- the negative effect on the ship is an increase in hull stress. The potential damages are those caused by such stress -- failure (to varying degrees) of the hull. Hopefully, though, anybody who's designed a ship to allow one prop at full forward and one at full astern has designed the hull to accomodate such a scenario. I imagine this would be used to tighten a turn radius, though I expect the drag caused by the rest of the hull is quite impressive. — Lomn 20:22, 26 February 2008 (UTC)[reply]

Killing the Bass[edit]

I, like many, are annoyed by certain people pumping up the bass in their cars to tremendous levels (sometimes at 4 in the morning) and have wondered about how to stop it. I imagined that there must be a way to make their bass speakers stop functioning using some sort of inverse sound wave or such. Naturally, I know practically nothing of such things - my mind just makes up pseudoscience at random. But I wonder if it would be possible in any way to kill someone's bass speakers using a device no larger than, say, a toaster. Don't misunderstand me, I have no intention of building such a thing, since that would bring me down to their level of rudeness. Is there any way to do what I propose without using EMP, entering the car, or anything of the firearm persuasion? (Edit: Scratch the no EMP part - how about EMP that only affects the specific type of speaker?) 206.252.74.48 (talk) 20:27, 26 February 2008 (UTC)[reply]

Oh, I very much want one of these. Here's one idea for such a system. In terms of scale, you've got to be able to generate enough of a sound wave to break somebody else's big speaker, which means you probably need a big speaker of your own -- so I expect a toaster is out. It also helps if you think of it as raising them to your level of politeness rather than vice versa :) — Lomn 20:43, 26 February 2008 (UTC)[reply]

Well, I already tune my radio transmitter (the kind that plugs into the cigarette lighter) to B96 (the local hip hop station) and blast Tchaikovsky through it. If they are listening to the station my little transmitter is picked up instead. The looks on their faces - absolutely priceless. It doesn't work that often because they use CDs, though. As for my theoretical device, I know the size constrant is a little small, but I originally imagined something I could fit in my pocket. 206.252.74.48 (talk) 21:02, 26 February 2008 (UTC)[reply]

You might also be interested in the active noise control article, the technology behind noise-cancelling headphones -- MacAddct  1984 ^{(talk  contribs)} 21:31, 26 February 2008 (UTC)[reply]

I have witnessed someone silence undesirable radios (not me - honest) by transmitting the IF frequency. The advantage of this technique is that you don't need to know what station the radio is tuned to as the IF is always the same. Again, not effective against CDs though. It might just be possible, though, that a transmitter tuned to some bit-rate used in CD players might be effective for similar reasons. SpinningSpark 00:55, 27 February 2008 (UTC)[reply]

You live in the US? Can't you just call up your local noise control officers to deal with the person making the noise? Nil Einne (talk) 08:41, 27 February 2008 (UTC)[reply]

I expected the USA solution to involve a gun. Shooting out the speaker should lower the volume significantly and deafen yourself enough so that you cannot hear! Earplugs are a lowercost solution to stopping the sound. Graeme Bartlett (talk) 10:29, 27 February 2008 (UTC)[reply]

This question is about my curiousity about such a system, I haven't heard any people blasting bass for a long time - they hibernate during winter, apparently. 206.252.74.48 (talk) 14:18, 27 February 2008 (UTC)[reply]

Constructive and deconstructive interference is spatially variant! (In plain english - you could "easily" generate a device which precisely tracks the audio signal phase and then re-generates it, out of phase, to "nullify" the signal, but you must measure the phase at a particular point in space - your microphone / sensor! Whereever you put your speaker, the phase will be different, and it may be nonlinearly dispersed. A convenient work-around is to only try to nullify the sound in one spot, such as on the interior of a noise canceling headphones unit. This is exactly the device you have described, and it is much smaller than a toaster. It is also much better at removing bass audio than treble, because the control-loop has more time to respond to changes in phase in low frequency ("slow") signals. Unfortunately, the good brands are a couple hundred dollars per unit, but I've been amazed at how effective they are. Nimur (talk) 23:20, 27 February 2008 (UTC)[reply]

As a side note, some experimental stealth aircraft have tried nullifying an incoming (radio, not audio) wave, at RF and higher frequencies. Such electronic countermeasures have varying degrees of success. —Preceding unsigned comment added by Nimur (talk • contribs) 23:23, 27 February 2008 (UTC)[reply]

Dream More...[edit]

hi,

is there any way to increase your dream rate?...eg any foods that make you dream more (does cheese actually work?)....an things you can do?

please keep it reletively simple thanks, --84.67.199.152 (talk) 20:49, 26 February 2008 (UTC)[reply]

There's a section on that in the lucid dreaming wikibook. [1] — Daniel 21:06, 26 February 2008 (UTC)[reply]

There's plenty of anecdotal and other evidence that suggests we all dream every night, but the percentage of dreams we remember in the morning is generally low. So it's not so much about about dreaming more, but remembering more. -- JackofOz (talk) 21:16, 26 February 2008 (UTC)[reply]

Well, I'm not aware of any way to increase your dream rate (and I don't trust those "dream pill" sellers, they look like snake oil to me). However, if someone monitors your sleep stage they could wake you up at the end of the REM stage, where you'd be more likely to recall your dreams. Most of the time you simply don't recall your dreams, and this method would allow you to recall more dreams than you normally would. -- Hi Ev 01:52, 27 February 2008 (UTC)[reply]

I don't know about anybody else, but I reliably have much more vivid dreams if I'm too hot, either because I accidentally left the heat on too high, or used too many blankets for the time of year, or have a cat sleeping on my head. —Steve Summit (talk) 01:59, 27 February 2008 (UTC)[reply]

Maybe sleeping uncomfortably (either physically or psychologically) might help? I've found cheese to work but this could be an anecdotal self-fulfilling expectation. — Æµ§œš¹ _{[aɪm ˈfɻɛ̃ⁿdˡi]} 09:04, 27 February 2008 (UTC)[reply]

It's definitely about the remembering. Keeping a dream journal, and writing immediately upon waking in the morning, caused an increase in the amount of dreaming I was remembering. It also increased my rate of lucid or semi-lucid dreams, which freaked me out so I stopped keeping the journal. The other main method that, in my experience, increases the rate of dream memory is waking up more often. For instance, getting pregnant and thus reducing the capacity of my bladder caused me to wake at night and remember more dreams. Similar results (if you don't want the consequences of pregnancy, or lack the anatomy) would probably be obtained by drinking a lot of water before sleep. Placing a small child, who needs to eat at intervals, next to you in the bed is also an effective method. moink (talk) 15:13, 28 February 2008 (UTC)[reply]

Also see Selective serotonin reuptake inhibitor#General side effects... "extremely vivid and strange dreams." --Allen (talk) 13:51, 29 February 2008 (UTC)[reply]

Faster Hair[edit]

hi,

is there anything you can do to make your hair grow faster........eg foods you can eat?

thanks, --84.67.199.152 (talk) 21:43, 26 February 2008 (UTC)[reply]

Nope, it grows at pretty much the same rate (about a half inch per month), no matter what you do.[2] MrRedact (talk) 22:21, 26 February 2008 (UTC)[reply]

If you sleep most of the time, it seems to grow a lot faster. Think Rip van Winkle —Preceding unsigned comment added by 79.76.241.79 (talk) 22:49, 26 February 2008 (UTC)[reply]

You could probably make it fall out though, by eating Strontium 90. SpinningSpark 01:00, 27 February 2008 (UTC)[reply]

It may or may not be an option for you, but you can make it grow much thicker by getting pregnant. —Steve Summit (talk) 01:55, 27 February 2008 (UTC)[reply]

I saw this only after responding to the above question. Maybe the questioner can address all her needs at once! moink (talk) 15:17, 28 February 2008 (UTC)[reply]

A healthy diet and the use of appropriate shampoo and conditioner, however, may contribute to slowing hair loss, which will affect the speed and maximum length your hair grows. Confusing Manifestation(Say hi!) 05:13, 27 February 2008 (UTC)[reply]

Watch out, though. Some anti-dandruff shampoos cause hair loss. kwami (talk) 07:48, 3 March 2008 (UTC)[reply]

Not anything that I know of...although there was a rumor that moving your head more often than usual causes more cells to die (tiny amount) therefore causing faster hair, but this has not been proven by ANY means, and I certaintly don't recommend walking around all day moving your head...:D Letter 7/Caleb (talk) 16:00, 3 March 2008 (UTC)[reply]

Shadow Dexterous Hand[edit]

Could a Shadow Dexterous Hand be used to replace a human hand if you lost one in an accident? If so, could you go further and replace a whole arm or leg with an air muscle limb, or even build a complete robot? DTWATKINS (talk) 23:54, 26 February 2008 (UTC)[reply]

The big difficulty to overcome with anything like this is the control connection to the human body (nerve ending or brain). Some progress has been made with these techniques but there is still a long way to go. See for instance Brain-computer interface and Cyberware. SpinningSpark 01:09, 27 February 2008 (UTC)[reply]

Another problem is that it needs both electricity and compressed air to run. So, even if you could overcome the control problems, you'd have to carry around a backpack with batteries, air compressors, and high-pressure air tanks in it. It would be pretty unwieldy, and occasionally noisy when the air compressor is running. -- Hi Ev 01:23, 27 February 2008 (UTC)[reply]

Wikipedia:Reference desk/Archives/Science/2008 February 26