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July 20

Tabby Markings in Lions

Why do lion cubs (possibly also adult lions) have the "M" tabby marking on their forehead, just as house cats do? See http://www.dailymail.co.uk/pages/live/articles/news/worldnews.html?in_article_id=469379&in_page_id=1811, see images 5 and 7. - MSTCrow 03:16, 20 July 2007 (UTC)[reply]

I've never noticed that before. I guess it's conserved patterns of gene expression for fur mottling. here's a great shot. Bendž|Ť 21:16, 20 July 2007 (UTC)[reply]

Mountain Lions (Puma, Cougar, etc. native to the Americas) also have kittens with tabby markings, but the adult is an even tawny color. The tabby markings provide excellent camouflage that is presumably advantageous to the vulnerable kittens. However, these large cats as adults have less need to be camouflaged and so lose their markings as adults. I'd have to check, but I think that almost (if not all) feline kittens have tabby markings regardless of the markings of the adults. This is a bit of a "just-so story", but it is a plausible explanation.--Eriastrum 15:49, 21 July 2007 (UTC)[reply]

To domesticate an animal, neotenous (kitten/puppy-like) traits are often selected over many generations. These are usually behavioural, such as a dependent personality, placidity, enjoying a good stroke behind the ear, etc, but I suppose there's no reason why kitten-like markings in adults couldn't be brought out in the breeding process. Bendž|Ť 20:58, 21 July 2007 (UTC)[reply]

Mechanical engineering

WHAT IS THE CURRENT CHALLENGES IN MECHANICAL OR MANUFACTURING ENGINEERING?

Mechanical engineering#Frontiers of research in mechanical engineering and the main articles listed therein. Someguy1221 06:09, 20 July 2007 (UTC)[reply]

The question I posted below is a perfect example of a current challenge of mechanical engineering... unfortunately. Nimur 06:20, 20 July 2007 (UTC)[reply]

The maintenance of old steam pipes?

Atlant 12:23, 20 July 2007 (UTC)[reply]

How to unstick all of those CAPS LOCK keys by the look of it. SteveBaker 01:10, 21 July 2007 (UTC)[reply]

More like sticky shift keys? Capuchin 07:59, 23 July 2007 (UTC)[reply]

IDEALLY how to make something out of nothing! Free energy is out there if we can just harvest it. Each Lightning bolt can power a city for a day, but how do you capture the energy (giant batteries connected to very high lightning towers in high storm areas like central florida??) More sun energy hits the earth each day than we could ever use, but how to capture it. Combatting waste is the avenue and to save our energy that is given by the sun and earth rather than let it get away. TripleBatteryLife 16:59, 23 July 2007 (UTC)[reply]

Generator Problem

Greetings Science Reference Deskers! One of our field teams is deploying a remote site in Alaska as we speak. They have purchased the Troy-bilt 5550 Watt Generator and have an interesting "show-stopper" of a problem. The generator has a pull-cord to start its engine, and apparently this cord "is stuck" and "will not pull." Our home-office version does not have this problem, and the generator seems to work fine here in the lab. What in the world could be causing this issue? The engine has been properly fueled and oiled and is brand-new. Unfortunately, the team is in too remote a site to easily "buy a new one" and we are furiously trying to get it working. Any small-engine experts know what we should do? Nimur 06:08, 20 July 2007 (UTC)[reply]

Ice? —Bromskloss 07:21, 20 July 2007 (UTC)[reply]

It's about 60 degrees Fahrenheit now, though. Nimur 07:24, 20 July 2007 (UTC)[reply]

Perhaps the cord is tangled and looped over itself. Or perhaps some extraneous matter has got into the clutch or something. You might have to take off the cover to see what is happening! Did the generator get transported with oil in it? If it was placed on its side, oil could have gummed up the spark plugs and stop it starting - though it should still turn over. TO fix this problem take out the spark plugs and clean them. GB 07:46, 20 July 2007 (UTC)[reply]

I'm no small-engine expert, but I agree with GB's suggestion about the cord. I think there's probably an easily-removeable cover over the pull-cord mechanism; your field team should remove that and see if anything's amiss. If there's nothing obviously wrong with the cord, they should then figure out some way of gripping the pulley (the one around which the pullcord is wound) very tightly and securely, and trying to turn it, slowly, by a small amount. It's at least somewhat likely that something in the engine has gotten stuck or seized, and that a larger force (larger than can be applied using the pullord, smaller than it would take to break anything) will unstick the engine, after which the pullcord can again be used to turn it over, after which (cross your fingers!) it will start. —Steve Summit (talk) 11:50, 20 July 2007 (UTC)[reply]

[But if the pullcord won't pull and the engine won't turn over at all, the spark plugs are definitely not the problem.]

Liquid lock might be a problem, especially if the generator set was tipped to some bizarre angle during shipment so oil or gasoline filled the cylinder(s). Remove the spark plug(s) and see if the engine can be cranked using the pull-cord.

Atlant 12:32, 20 July 2007 (UTC)[reply]

Definately a good idea to try, also there is a chance of glazing loose in the cylinder if the generator has been run with no load and then transported. Have a look in the cylinder.Polypipe Wrangler 11:06, 21 July 2007 (UTC)[reply]

It's a smaller engine, but I have known my lawnmower pull start to jam. I have gotten it loose by repeated jerking and releasing the cord. Cussing it in the process seemed to help. Not sure exactly what the mechanism of it getting stuck was. Edison 20:51, 20 July 2007 (UTC)[reply]

If it's brand new (never been started) it may have something in it to prevent the parts from moving during shipment and causing damage. If so, the instructions would likely include a way to remove such devices. StuRat 02:09, 23 July 2007 (UTC)[reply]

If it's brand new and has a locking device, the locking device probably also has a big bold message that says something like "No oil in engine; add 10 oz. oil before starting!". Follow that advice ;-).

Atlant 12:43, 23 July 2007 (UTC)[reply]

OIL TURNS TO CONCRETE WHEN FROZEN! ! You'll have to heat up the generator then drain the oil and then put in lighter oil (in alaska 5-20w was common. I actually had to heat my oil pan with a coleman camp stove for 3 hours in 70 below weather in canada (beavercreek BC) to get it to start. Don't break your rope trying to hard. You can use gasoline in a metal pan to create heat if you have no other way. Hope this helps! TripleBatteryLife 17:06, 23 July 2007 (UTC)[reply]

However, as the author said "It's about 60 degrees Fahrenheit now." StuRat 07:25, 24 July 2007 (UTC)[reply]

Principle of the hand pump

WHAT IS THE PRINCIPLE OF HAND PUMP?

Firstly, let me be the first to commend you for your eloquent and polite question. As for your actual question, there's some very sketchy information at hand pump - but maybe some of the types of hand pump may help you find specific information about how these work. Google is your friend. Good luck. Aaadddaaammm 09:52, 20 July 2007 (UTC)[reply]

Pump#Positive displacement pumps seems to be the right place to look.

Atlant 12:34, 20 July 2007 (UTC)[reply]

Are humans the most successful creatures on earth?

In terms of numbers of individuals, or in terms of total biomass, where are humans in the success stakes compared with other species?

And I'm always surprised to learn that there are more for example cows in my country than humans - do they have secret underground cities? 80.2.192.45 11:10, 20 July 2007 (UTC)[reply]

Insects would be far more populous than humans or cows. Ants for instance are pretty kick ass when it comes to huge numbers. The most 'sucessful' 'creatures' however could possible be considered bateria (5×10³⁰ in the world according to the article) or viruses although it all depends which criteria you choose to use to measure success. Lanfear's Bane

Although, neither insects, viruses nor bacteria are a species. But there could well be one species from within these groups that fits the required criteria. It always grates with me when people say things like 'humans have only been around so long, dinosaurs ruled the earth for millions of years'. Well that's hardly a fair comparison! Yes defining success is difficult, there are more cows because humans grow them for food, who's the more successful there? Anyway to quote from our Biomass (ecology) article: 'The most successful animal, in terms of biomass, is the Antarctic krill, Euphausia superba, with a biomass of probably over 500 million tons, roughly twice the total biomass of humans.' Cyta 11:37, 20 July 2007 (UTC)[reply]

That very last figure sounds a tad dubious; although they don't state whether they mean wet or dry mass, the fact that the overall source seems to be about krill as food suggests that they mean wet mass. Assuming an average body mass of 70 kg (slightly less than highly developed countries, slightly more than less economically developed countries), * 6.5 billion people gives an approximate biomass of 455 million tonnes; virtually the same as the krill. Laïka 17:49, 20 July 2007 (UTC)[reply]

You're forgetting that a large fraction of humanity (as represented by that 6.5bn figure) are children - some a light as a couple of kilos. It wouldn't surprise me to find that the average human weighed in at 35kg on that basis. So I can believe Krill have out out-massed 2:1. SteveBaker 01:08, 21 July 2007 (UTC)[reply]

Not only that but given that the majority of people are from less economically developed countries, 70 kg seems a little high even for adults to me. Nil Einne 12:55, 23 July 2007 (UTC)[reply]

Let's look at some different ways to measure success:

1) Number of individuals alive now. We rate very low on this scale, as would all large organisms (although we rate well relative to other large organisms).

2) Largest biomass. We rate quite well here, although perhaps not quite at the top.

3) Longest species longevity. We're pretty pathetic here, being a relatively recent species.

4) Longest individual longevity. We're not so good here, as many plant species, and a few animals, have us beat.

5) Ability to alter our environment. We may be in the lead here, although the alterations to our environment aren't always to our advantage, like global warming.

6) Intelligence. We have the other species beat by a long shot here.

7) Range of habitats. We are quite high in the range of habitats on land we can manage. However, as there is so much more water than land on Earth, some marine species would likely beat us here.

However, if we can manage to survive long enough to spread our species to other worlds, this might increase our biomass (and eventually species longevity) well beyond other species.

Reflection

Hi, I was reading the Wikipedia article on 'Reflection' and came across this phrase which I don't really comprehend - 'the photon absorbed by the molecule may match energetic levels of the molecule. I would be very grateful if anyone could explain what it means. Thanks!

Full context:

As the photon absorbed by the molecule may match energetic levels of the molecule (kinetic, rotational, electronic or vibrational), the photon may not be reemitted or alternatively may lose some of its energy in the process. The emitted photon will have a slightly different level of energy.

When the photon hits the molecule, it gets completely absorbed, adding some form of energy to the molecule. Depending on the original state of the molecule and the amount of energy in the photon, the new state may be stable or unstable. If it's stable, the molecule will not emit a photon, in which case the photon has not been reflected. If it's unstable, the molecule will emit a photon, but not necessarily one with the same amount of energy.

Say that some property of the molecule has stable points at 3, 5, and 12 units of energy. If it's sitting at 3 and a photon with 7 units of energy hits it, it will jump up to 10. 10 is unstable, so the molecule emits enough energy to drop down to 5, the closest stable point. That means that the reflected photon will have only 5 units of energy.

Now imagine that another photon with 7 units of energy hits it. This time, it goes up to 12. 12 is stable, so no photon is emitted, and the photon has been (in the classic sense) absorbed.

Hope that helps! -FunnyMan 11:57, 20 July 2007 (UTC)[reply]

The simple fact that is lost in all this physics is the following: If the atoms absorb the photon and immediatly re-emit them in a coherent manner, this is reflection. "Coherent" means that it fits into the phase (the "rhythm" of oscillation) which ensures that the light goes in the right direction. If the photon is absorbed and not re-emitted at all as visible light, then this colour is not reflected. Silver, for example reflects all colours, while copper canot reflect the blue part of the spectrum, and this is why everything refelected off copper (and hence copper itself) has a redish hue. Simon A. 14:58, 20 July 2007 (UTC)[reply]

Sharlel Mary Talo Palsy?

My girlfriend's brother has a type of palsy called sharlel mary talo palsy, but I am not sure hoe to spell it so I can't find any information on the subject. If anyone knows the correct spelling of this condition, please advise! Thanx in advance! Steve (removed email signature) —Preceding unsigned comment added by 209.206.132.56 (talk • contribs)

Never heard of that particular name of a palsy, but are you referring to Charcot-Marie-Tooth disease? -- JSBillings 13:44, 20 July 2007 (UTC)[reply]

an indelicate question

I noticed when cleaning my bottom in the shower after a bowel movement that there are insoluble, fine sand-like particles from the feces. What kind of substance(s) would these be? --Halcatalyst 14:35, 20 July 2007 (UTC)[reply]

For medical advice you should consult your doctor. It could however simply be sand. Have you been to the beach recently? Lanfear's Bane

I'm not looking for medical advice, since I'm not experiencing any illness, and no, I haven't been to the beach in a long time. Rather, I take this to be a normal occurrence which I've noticed for a long time, and I'm looking for information related to intestinal processing, presumably with respect to normal diet. --Halcatalyst 15:50, 20 July 2007 (UTC)[reply]

Do you eat a lot of bread made from stone-ground flour? DuncanHill 20:14, 20 July 2007 (UTC)[reply]

No. I'm wondering if these particles might be accumulations of minerals in the diet. (I'm pretty sure it isn't just me. I've noticed it because my shower drain is flat and in a couple of spots the water (and particulate debris) doesn't flow away. It helps that the floor is white.) --Halcatalyst 21:04, 20 July 2007 (UTC)[reply]

They may be the stone-like little gritty things you find in some fruit auch as pears. They might be something like gall stones although perhaps not in such quantity. Or they might be bits of peanuts or other nuts. A lot of things like sweetcorn come out of your rear end unchanged.

There is often grit in fresh veggies, like celery, so perhaps you need to wash them more thoroughly. Also, if you eat things with bones in them, like sardines, perhaps a rounded piece of bone makes it through the digestive system. StuRat 01:12, 23 July 2007 (UTC)[reply]

It could be small seeds. Or if you've eaten low-quality hamburgers, sausages etc it could be little bits of ground up bone. Might even be the remains of red-blood cells which, I understand, are excreted when old. Have you looked at them under a microscope?

A microscope! Of course, that would be the way to go. But I have none....

It dawned on me that I could look up Human feces. It didn't say anything about small particles, but it would be hard to imagine that feces would be entirely water/soap soluble, I guess. --Halcatalyst 21:39, 24 July 2007 (UTC)[reply]

Psychopathy vs suicide rate

I have been reading the Wikipedia article on psychopathy, and it is said that Hervey Cleckley asserts that psychopaths are not likely to commit suicide as they score high on both of the PCL-R factors. Yet it is said that Factor 1 is not related (istead of negatively related) to suicide and factor 2 strongly correlated to suicide, shouldn't that mean that psychopaths should also be very susceptible to suicide? Thanks! —Preceding unsigned comment added by 58.153.96.35 (talk • contribs)

Pollination of sacred fig (peepul tree, bo tree)

Britannica says: "Each fig species are pollinated by species-specific wasps." (Under Ficus) Is this true? Sacred fig (aka as peepul or bo tree) has very tiny fruit. Does pollination occur with the help of fig wasp in bo tree? Thanks in advance for your valuable instruction. —Preceding unsigned comment added by 58.216.233.166 (talk • contribs)

Another question Sacred fig says that Peepal ..."is a species of banyan fig native to Nepal and India"... Is this true? Isn't banyan another species of the Ficus genus?

Also, does peepul send out aerial roots like banyan? As we know, banyans can have massive prop roots which grow into parallel trunks as this image shows. Though I haven't seen a peepul with such prop roots, peepul always have extremely gnarled trunk, as if many many smaller trunks stuck together to form the trunk, as seen in this image

LASER RADAR (LIDAR) operated by police

help. is there any way to beat the lazar radar used by police. the make is atlantis.

thanks,

u.k.nown —Preceding unsigned comment added by 204.138.85.6 (talk • contribs)

We have an encyclopedia article about LIDAR if you care to read it. Friday (talk) 18:07, 20 July 2007 (UTC)[reply]

Laser ranging is particularly sensitive; far more so than plain radar, so it is very difficult (read impossible) to beat, even if you were to coat your car with matt black paint which would normally beat a light-operated device (laser ranging is so powerful that it can even pick up reflections of thin clouds of water vapour). There is only one surefire method: slow down. Of course, this is only good for a laser radar; the easiest way to beat a lazar radar is to take a mixture of rifampicin, dapsone and clofazimine once a day for the leprosy... Laïka 18:17, 20 July 2007 (UTC)[reply]

When my father was trained on the laser radar gun, he was told to aim for the headlights because they provide a much better reflective surface. So, if you are paining your car flat black, ensure you either remove or paint over the headlights also - and don't drive at night. -- Kainaw^(what?) 19:12, 20 July 2007 (UTC)[reply]

Here in Texas, they train the cops to aim the laser at the front license plate - and only to go for the headlights if there isn't a front plate (which is illegal in Texas anyway). The license plate has a retroreflective coating and the headlights have parabolic reflectors - both ought to give a nice strong return for the laser. Painting over your headlights probably wouldn't help - but it would be illegal anyway - I'm betting the speeding ticket would be cheaper! SteveBaker 05:31, 21 July 2007 (UTC)[reply]

Given that our Mr. Nown knows the model of the laser gun that caught him, I'm guessing his court date is already set, and that's the venue where he hopes to "beat" it. (Requiring, of course, a whole different set of strategies.) —Steve Summit (talk) 12:05, 21 July 2007 (UTC)[reply]

...which would require us to offer legal advice - which we aren't allowed to do. SteveBaker 14:13, 21 July 2007 (UTC)[reply]

Well, if you can prove variable speed of light in a court of law, not only would you quash your conviction, but probably get rather rich and famous off it... Laïka 19:05, 21 July 2007 (UTC)[reply]

The speed of light is variable - it depends on the material it's travelling though - it's only the speed of light in vacuum that's constant. SteveBaker 21:54, 21 July 2007 (UTC)[reply]

I have been told that one can buy effective LIDAR jammers that use infrared light-emitting diodes mounted around one's front license plate frame. These LEDs re arranged to emit a pseudorandom binary sequence that the LIDAR cannot analyze. That is, the LIDAR can't locate its own pulse returns among the many flashes of LED light that it sees coming back at it.

Last I knew, these were generally not illegal in the United States (certainly don't violate any FCC regs), but that would venture into the "legal advice" domain.

I do not now own nor have ever owned or operated such a device, so I can't really vouch for their effectiveness or legality.

Atlant 12:39, 23 July 2007 (UTC)[reply]

This technical document explains things very nicely: http://www.mr2.com/TEXT/FAQonLidar.html - the conclusion seems to be that LIDAR is effective, hard to avoid and hard to jam. As for the legality - as it points out, there is a general "Interfering with the duties of a police officer" offense that probably covers all efforts to avoid lidar speed detection. SteveBaker 13:06, 23 July 2007 (UTC)[reply]

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thank-you everyone for responding with all the useful information. sorry for delay in responding, was indisposed. you people are fantastic. By the way I was questioning this as three cars were pulled over at the same time. I did not think that was possible or even allowed. U.N.Nown.

Hypothetically moving a mountain

If one were to move a mountain or the weight equivalent to one, what would be the most scientifically sound way to do so. Even though impossible, what would be the closest way?

A bunch of dump trucks. Clem 19:05, 20 July 2007 (UTC)[reply]

Correct - divide and conquer. -- Kainaw^(what?) 19:10, 20 July 2007 (UTC)[reply]

Don't take my word for it, but I'd consider the following. First of all, we don't want to lift the mountain at all, because the work necessary to lift a mountain even a small amount would be enormous. I can imagine slowing cutting the base of the mountain, replacing the stone removed by two thick layers of solid steel (that could support the wieght of the mountain); the bottom one attached to the ground and the rop one attached to the base of the mountain. If you place a thin layer of teflon on the contact surfaces and a very thin layer of lubricating liquid, you could get the friction down quite a lot. Also, to further reduce the friction, you could use maglev technology to reduce the normal force produced at the contact surface (we probably couldn't get the mountain to levitate, but the repulsion would have an effect equivalent to further reducing the fiction coefficient). Once all that was done, maybe you could slowly slide the mountain to one side. --Waldsen 19:11, 20 July 2007 (UTC)[reply]

p.s. My way is nice to imagine, but in practice it would be an engineering nightmare (practically impossible). --Waldsen 19:16, 20 July 2007 (UTC)[reply]

You would have an extremely long chute that could remove the material from the top as far away as possible, so the rock would initially be distributed in a circle around the mountain. As the mountain got lower you'd use a shorter chute(s). The mountain would be moved as you said. You didnt say anything about keeping it the same shape. 80.0.105.59 19:21, 20 July 2007 (UTC)[reply]

I think it said in a documentary I saw that they pretty much fully demolished a mountain during the construction of KIX in order to build the artificial island. Philc 19:41, 20 July 2007 (UTC)[reply]

How large is the cross section of the mountain in the plane where it is to be cut, and what is its mass? Large buildings clearly are orders of magnitude less massive than a typical mountain, but they have been separated from their foundation and placed on springs for earthquake protection. Large buildings, even lighthouses, have been jacked up and moved by house movers.Cleopatra's Needle is the name given to several stone obelisks which were move between countries in ancient times and more recently. Our ancestors 5000 years could move large stones with rollers or skids and muscle power. Saturn V moon rockets and the Space Shuttle are routinely driven to the launch pad by a gargantuan lowboy. So in principle, I would prepare a roadbed which could support the weight, perhaps using multiple parallel rails and wheeled assemblies on either side similar to but vastly scaled up from railroad wheels and axles. Perhaps multiple wheels, rails, and bearings in an assembly on each side. Hydraulic jacks would take up the strain to support it after supporting beams were inserted in holes drilled through it, and below those holes the cut would be made completely through it. Roll it along the roadbed to the new site where a foundation has been prepared, lower it into place, remove the beams, cement up the holes, which would be below the finished grad, and voila. Rather than assuming it is impossible, it would be a good exercise for a mechanical engineer to calculate the upper limit of early 21st century technology to move a mountain. Assuming cost was no object, like the Pyramids, Space Program, or the present global war budget, then it could be cut into the largest hunks that today's technology can move, moved, and reassembled at the destination. (Number the pieces to keep track and avoid a jigsaw puzzle). The Abu Simbel temple, carved out of solid stone, was moved in this way from 1964 to 1968 at a cost of $80,000,000 to save the World Heritage feature from being submerged by a lake. I don't know the total mass of stone moved or the max weight of each block.Edison 20:41, 20 July 2007 (UTC)[reply]

Edward Teller used to quip, "If your mountain is not in the right place, just drop us a card." --24.147.86.187 21:36, 20 July 2007 (UTC)[reply]

Well, you have not specified whether the mountain must be intact after its move. In Seattle the city did actually “move” a mountain at one time. They just aimed a bunch of fire hoses at it for a while and washed in into the Puget Sound, I believe. It probably killed of a lot of the salmon. These days that would never be allowed. --S.dedalus 22:28, 20 July 2007 (UTC)[reply]

Heh I was going to mention the Denny Regrade myself. Then there is Mountaintop removal mining, which essentially moves mountains. The question is, do you want the mountain to be in the same shape after you move it, or is it ok to just be a thick flat layer of debris? Pfly 01:12, 21 July 2007 (UTC)[reply]

Undermine the mountain on an inclined plane, replacing the rubble with sand (like in the old mines at Broken Hill) and fitting high pressure water pipes as you go. Then turn the water on and stand clear. Even better if the last part is done just before an earthquake. Round desert sand should work better than sea sand. Polypipe Wrangler 11:23, 21 July 2007 (UTC)[reply]

Use a river. But, of course, only if you are moving the mountain downhill. Otherwise, announce there's coal under the mountain and have a mining company move it for you.

Atlant 12:48, 23 July 2007 (UTC)[reply]

The book How Would You Move Mount Fuji? tells how a number of Microsofties would try it. --TotoBaggins 18:18, 23 July 2007 (UTC)[reply]

Chuck Norris (somebody had to say it), and with the slicing through the bottom of the mountain, assuming it was feasible, might make moving the mountain easier if cut at incline, so perhaps it could be sluoghed onto rollers for more moving without any or realatively little proding, it addition to teflon69.29.94.95 05:51, 26 July 2007 (UTC)[reply]

batteries constructed on chip same as transistors on ICs

Is there a battery or electricity storage device that is constructed on a chip such that the chemical/physical components of the capacitor or electrochemical cell (LiFePo4) have been implemented at the nanoscopic level? If so has such technology been stacked and used to provide power for larger battery powered devices in place of a conventional battery? Clem 19:04, 20 July 2007 (UTC)[reply]

I remember reading somewhere on the Internet recently about a little device that gets electrical energy from vibrations and thus powers things without batteries. 80.0.105.59 19:14, 20 July 2007 (UTC)[reply]

The article Micropower would be a good place for covering the new device which gets power from vibrations or the battery on a chip , but those have apparently not been added yet. A battery built into a chip sounds like a very high expense item, if the implication is that both the battery and the device it powers is on the chip. Then when the battery gets low, you have to replace the device as well? At the present time, PCs have a backup battery with a shelf life odf several years to keep configuration info memory powered, and it is fairly easy to replace the battery. A backup battery may not have to furnish appreciable current as long as the device has power, and the drain can be extremely snall even without power. I suppose there is no reason a microscopic battery could not be built, and be capable of furnishing several volts, but the amp-hours would have to be correspondingly minute. Edison 20:21, 20 July 2007 (UTC)[reply]

Well I would assume any battery design committed to a chip would also be rechargeable especially if charged from vibrations. But what I am getting at is more like a conventional battery that has been reproduced at the microscopic level not to power an included circuit but rather as one of a trillion basic cells that would all be wired together as an alternative to say using airgell to maximize the surface interface between say lead and sulphuric acid. Clem 23:57, 20 July 2007 (UTC)[reply]

I recall an article on the construction of supercapacitors using bioengineering. The growth of some organism through a carbon filament created a capcitor with a great amount of surface area. No link, sorry!

Natural biological capacitors, such as phospholipid membranes, have a dielectric breakdown constant on the same order as materials used to insulate high tension power lines, as I recall. The problem, of course, is that they're tiny and generally useless as capacitors except as nature intended, but they have intriguing possibilities. Someguy1221 03:45, 21 July 2007 (UTC)[reply]

Generally speaking, integrated circuit chips and on-going chemical reactions don't get along well. Those chips that seem to contain a battery (some non-volatile CMOS RAMs, time-of-year clocks, and the like) usually contain an actual, discrete lithium battery in the overall package.

Atlant 12:52, 23 July 2007 (UTC)[reply]

fates worse than nature

this is with reference to the question asked a few days back. i was thinking about these parasitoids and their amazing ability to control the minds of the hapless bugs. is it possible for them to evolve to something that could possibly target humans? for instance, like that ant which was made to wait on the grass to be eaten by the cow - i would be quite upset(to say the least!) if i were made to, say, enter a river full of crocs just to complete the life cycle of a parasitoid! 59.180.95.229 21:45, 20 July 2007 (UTC)RSP[reply]

See toxoplasmosis#Behavioral changes for a possible example of a known parasite that may impact human behaviour. Dragons flight 22:01, 20 July 2007 (UTC)[reply]

It wasn't in the article, but I saw something the other week which related the supposed tendency of toxoplasmosis to make women more affectionate to the sterotype of the ...... woman with a houseful of cats. hmm. Gzuckier 15:44, 23 July 2007 (UTC)[reply]

Also rabies for a definite and easily noticeable (and nasty) one. —Ilmari Karonen (talk) 11:21, 21 July 2007 (UTC)[reply]

Well, rhinovirus makes you sneeze. It's the same idea. Similarly, cholera, for instance, makes you generate large quantities of diarrhea which is virtually colorless and odorless, and is highly infectious. The advantages for the spreading of the disease over having nasty diarrhea which would make nurses etc. wash their hands and the sheets etc. thoroughly are obvious. It doesn't always have to be changes in the brain to change behavior. And then there's rabies, which makes normally shy animals wander out in the street at noon and pick fights. etc. Gzuckier 15:42, 23 July 2007 (UTC)[reply]