Wikipedia:Reference desk/Archives/Science/2008 June 22

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June 22

Is there a name

Not sure if this is science but Is there a name for some one who is interested in sniffing the smell of there own farts (not others) —Preceding unsigned comment added by 79.76.232.210 (talk) 00:23, 22 June 2008 (UTC)

It is a type of olfactophilia or osmolagnia. Mac Davis (talk) 01:25, 22 June 2008 (UTC)

This one's been up before but you'll need the link. Julia Rossi (talk) 01:56, 22 June 2008 (UTC)

Also, Flatulence#Composition of flatus gases. Mac Davis (talk) 02:11, 22 June 2008 (UTC)

My answer is definitely not science, but the name would be Franamax :) I always take a certain pride in my own disgusting emissions, and yes, the flatulence of others is a completely different situation. I have no idea why that is, and it is definitely not sexual in nature, not even close. Maybe it has something to do with looking in the toilet when you're done, whereas looking at other people's products is something really no-one would want to do. I'm not a weirdo, really! I don't think it's all that uncommon to take more interest in one's own emissions than those of others, however none of the links above really describe what I'm thinking of. Franamax (talk) 03:59, 22 June 2008 (UTC)

I don't know about 'interested' but I would expect most people are more familiar with their own smells hence are less likely to be repulsed or disgusted by them. Similiar for example to the way someone who works in a mortuary will be used to the smells there Nil Einne (talk) 11:23, 22 June 2008 (UTC)

Insert South Park reference here. — The Hand That Feeds You:^Bite 12:56, 22 June 2008 (UTC)

And let's no forget Terrence and Phillip. StuRat (talk) 15:07, 22 June 2008 (UTC)

Or Fat Bastard: "Oh, everyone likes their own brand, don't they?" Zain Ebrahim (talk) 17:32, 23 June 2008 (UTC)

I can make up a name for you: flatophilia. StuRat (talk) 15:07, 22 June 2008 (UTC)

A very similar question was asked here JessicaN10248 16:57, 22 June 2008 (UTC)

It strikes me now that smelling your own farts, like looking at your own poo in the toilet, is really just another way of assessing your own health and bodily condition, one of a great number of assessments we do as a matter of course. Unless the habit is pathological (i.e. interfering with your life), I'm not sure there would be any specific name for it.

OTOH though, 'fess up people, who here doesn't enjoy dropping a silent bomb just before stepping out of the elevator? :) Franamax (talk) 07:07, 23 June 2008 (UTC)

Psychology website

I Know that Wikipedia doesn't answer questions that deals psychology, but is there any website that can take psychology questions? —Preceding unsigned comment added by 76.64.128.65 (talk) 01:42, 22 June 2008 (UTC)

If it's about Psychology, why not? Try us in a way that avoids asking for a diagnosis, but is about human behaviour, history, careers, models of psychology, applied research, fields, lists and interpreting any of these, you might get lucky. Best, Julia Rossi (talk) 01:53, 22 June 2008 (UTC)

Your question will probably be deleted if you mention there is a real world situation. Physics Forum's medical section is much less strict and there are plenty of real experts there, and in their medical section.[1] Mac Davis (talk) 02:15, 22 June 2008 (UTC)

But questions about psychology shouldn't be discouraged. We just don't want to give you the idea that you should take what we say as medically-valid advice. We are just volunteers, after all! However, now you've got me curious... what's the question? L'Aquatique[review] 06:33, 22 June 2008 (UTC)

If you don't know anything about it, read up on the basics of Psychology and phrase your question so that it is clear that you want to learn about this or that you're looking for information on that and I don't think that you would have a problem. Zain Ebrahim (talk) 09:05, 22 June 2008 (UTC)

Ask about memory drums, selective attention, the Law of Effect, operant conditioning, tachistoscopes, the Stroop Effect Skinner boxes, T mazes, or lots of other psychological topics, and you are likely to get a good answer. Ask why you hear voices telling you to harm yourself or others, or how to cure your depression, and you will be told we do not offer medical advice. Get the drift? Edison (talk) 03:04, 23 June 2008 (UTC)

No, I mean is there any website where I can ask questions or tell my problem to a psychologist? —Preceding unsigned comment added by 76.64.128.65 (talk) 01:42, 22 June 2008 (UTC)

Why don't you go to an actual shrink? 125.21.243.66 (talk) 12:24, 27 June 2008 (UTC)

Pain

What's the most severe physical pain a human can feel? What about emotional pain? Thanks.

Cluster headaches are meant to be right up there. Angus Lepper^{(T, C, D)} 10:40, 22 June 2008 (UTC)

5 or 10? Nil Einne (talk) 11:20, 22 June 2008 (UTC)

As Nil Einne points out, pain is treated on an individual basis in medicine. My worst pain (a broken arm) doesn't compare to many of the people I've seen come through the ER. — The Hand That Feeds You:^Bite 12:58, 22 June 2008 (UTC)

I've heard kidney stones and pregnancy are some of the worst 'natural' pains that can be experienced. I'm sure stabbing is painful too, though. Regards, CycloneNimrod ^talk?_contribs? 13:33, 22 June 2008 (UTC)

I heard the same thing, as well as circumcision when you're an adult. ~Amatulić (talk) 20:54, 23 June 2008 (UTC)

Hospital patients are often asked to rate their pain on a scale of 1 to 10, and this info is used to determine the amount of pain killers they are given. The problem, however, is that the "10" will be very different for a patient who has had severe burns versus one who has never had anything worse than a splinter. I've often thought the nurses need to help the patients to properly calibrate their level of pain, by using a cattle prod set at various power levels. :-) StuRat (talk) 14:58, 22 June 2008 (UTC)

I've always imagined being lowered into a vat of boiling acid and having your organs fall out and boil while you're still alive to be the most painful experience possible. Of course, if a machine could stimulate the nerves to cause pain, you could probably experience a lot more pain with little physical damage. JessicaN10248 15:08, 22 June 2008 (UTC)

Well there is Dolorimeter. But I guess the point is to some extent it doesn't matter. The primary point of pain assessement is for pain management, e.g. adjusting analgesia dosages or types, working out if it's getting better or worse. The fact that person A's 10 is different from B (whether because of different tolerances or different experiences) doesn't matter quite so much. However there ae obvious problems when people serious overestimate their pain [2], you don't want to be treating someone as having extreme pain when they aren't. (And clearly it's a problem if you are using the pain level to assess which patient to treat first.) Childbirth appears to come up a lot for females, for males perhaps having your testicales crushed slowly is a good example. Nil Einne (talk) 15:31, 22 June 2008 (UTC)

Congenital insensitivity to pain with anhidrosis is the opposite of what you're looking for. Nociception is the physical feeling of pain, suffering is meant to include psychological and physical pain, and then there's also phantom limb pain, and algolagnia. Mac Davis (talk) 19:25, 22 June 2008 (UTC)

I have generally told nurses asking me to rate some pain on a scale of "1 to 10" that before the pain reached "10" I would be writhing on the floor and screaming. Edison (talk) 03:00, 23 June 2008 (UTC)

Do you say you have 10 anyway (as mentioned in the above link) Nil Einne (talk) 14:03, 23 June 2008 (UTC)

On hair loss

Two questions about hair loss have been bugging me for a while

1) Is human hair loss seasonal? In other words do humans " shed " like dogs do? 2) Is male hair loss gradual or are there periods of more intense hair loss followed by periods without hair loss?

Wikipedia doesn't appear to have the answer to these questions. PvT (talk) 12:49, 22 June 2008 (UTC)

1) I don't believe people shed, no.

2) Yes, hair loss is periodic. Many men lose hair up to a certain point, and then lose no more. The fringe around the back commonly remains until death. StuRat (talk) 14:28, 22 June 2008 (UTC)

Google is your friend here; use keywords like seasonal hair loss. Yes, some people do notice – usually minor – seasonal hair loss. Typically seasonal hair loss manifests in autumn [3]. The cause has not be definitively been identified, but it is well established that there are seasonal changes in the levels of many hormones in the body, some of which do regulate hair growth. TenOfAllTrades(talk) 15:26, 22 June 2008 (UTC)

Mould is a floater?

(Question copied from Talk:Mold)

Whenever we chuck food down the toilet that is mouldy, we have a hard time flushing it because it floats. Is there a scientific explanation for this? 125.236.191.140 (talk) 08:57, 22 June 2008 (UTC)

Hmmmm... Have you tried flushing non-mouldy food for comparison? I suspect the mould has nothing to do with it, and that flushing things down the toilet is just harder than you'd imagine. But I can think of two possible reasons why mould might make a difference (and I am speculating here):

• Many moulds produce special proteins called hydrophobins, which repel water. If you put fresh bread in the toilet it will quickly absorb water, but I guess very mouldy bread might retain some dry regions; the air in these regions might keep the bread buoyant. What kind of food have you been flushing?
• Ordinary moulds produce carbon dioxide, a gas, as they respire. If this were to form gas pockets within the food, it would increase the food's volume, reducing its average density and increasing buoyancy.

Adrian J. Hunter^{(talk•contribs)} 15:46, 22 June 2008 (UTC)

The type which is made of many fine hairs should be just about ideal for trapping air bubbles. StuRat (talk) 17:33, 22 June 2008 (UTC)

It's not a good idea to put food down the toilet, and may be illegal. See here and here for example.--Shantavira|^{feed me} 18:28, 22 June 2008 (UTC)

Digest it first :)--Lenticel ^(talk) 03:48, 23 June 2008 (UTC)

Research alone

Is it necessary for a man to be super rich to be able to setup a lab at home? If not, where can I buy basic (college-level)lab equipments?--218.102.124.108 (talk) 16:26, 22 June 2008 (UTC)

That would depend on the lab. If you want to set up your own test nuclear reactor, then yes, you would need to be rich. If you want to set up a lab for testing the pH of various non-hazardous chemicals, then $10 for some pH strips should do it. StuRat (talk) 17:29, 22 June 2008 (UTC)

For a (very) basic setup, you could buy a chemistry set for next to nothing, add some bunsen burners, test tubes, goggles, magnets, and various other lab equipment. You can probably find all this stuff on amazon or ebay. JessicaN10248 17:44, 22 June 2008 (UTC)

I would also recommend you invest in a lab coat since non-hazardous doesn't mean they won't stain your clothes. And perhaps some gloves Nil Einne (talk) 18:56, 22 June 2008 (UTC)

Read some threads online about setting up an amateur improvised home lab.[4] There are plenty of things you can get if you just keep an eye out. Edmund Scientific[5] has historically been a great place to get equipment, and Ohaus[6] makes great measuring equipment (you will definitely need a triple beam balance or scale. United Nuclear[7] is my favorite place though. It's more geared towards the home amateur, and has good prices for small amounts of chemicals. When looking for prices, always check eBay. I've bought plenty of stuff from eBay, with no problems at all. Make sure you purchase from businesses and people with good ratings. If you have a chemistry teacher and get to be friends, if you ask politely, you can probably borrow some chemicals or do some investigation after school. Mac Davis (talk) 18:58, 22 June 2008 (UTC)

Be aware that amateur chemistry tinkering is a bad idea if you lack formal education in it. Much of chemistry is toxic and much of it is explosive, even relatively innocuous things (as a simple example, something as simple as water and electricity can generate extremely flammable gases, and many simple and standard acids can scar your lungs if you don't use them with proper ventilation). Just a head's up. For every Thomas Edison there are about twenty guys who accidentally electrocuted themselves. --98.217.8.46 (talk) 20:58, 22 June 2008 (UTC)

It is very dangerous. Try and get to know a few people in real life that you can work with and have experience in the lab in whatever field you are experimenting in. Chemistries, electricity, mechanics, and computing all have different lab saftey procedures. You can't learn if you're dead.! Mac Davis (talk) 22:51, 23 June 2008 (UTC)

If what you're planning is interesting enough you could always consider looking for funding or trying to gain use of existing labs (universities or private sector). --Shaggorama (talk) 07:01, 24 June 2008 (UTC)

If all parts of the LABURNAM tree are poisonous,when the petals fall and decay is the poison carried into the soil making it poisionous to other plants.

If all parts of the LABURNAM tree are poisonous,when the petals fall and decay is the poison carried into the soil making it poisionous to other plants.How does it affect the soil structure? —Preceding unsigned comment added by 82.20.40.20 (talk) 16:51, 22 June 2008 (UTC)

The toxin in Laburnum trees in called Cytisine. There is lots of information about it's effects on people and animals, but I can find none about soil. Hopefully a chemist will be along shortly to help out. JessicaN10248 17:17, 22 June 2008 (UTC)

It's possible, if the poison doesn't rapidly decay, but it would be so diluted by this process that I doubt if any noticeable effect would occur.StuRat (talk) 17:23, 22 June 2008 (UTC)

The poison is targetted against predators which have nervous systems. Plants don't have any use for nerves so I don't think that it will affect them.--Lenticel ^(talk) 02:41, 23 June 2008 (UTC)

Thank you Jessica,StuRat and Lenticel for the info so far.My problem is that a few weeks ago the flowers all dropped very quickly as they do each year,and I get a 1 to 2 inch mat of dying petals covering our flowerbed if left they form a thick mat that is very solid and can be picked up in lumps for some days.Some plants will not grow in this situation,is this due to the the amount of petals smothering the soil(leaf mould-helpful) Have you got a clue, or am I just a sloppy gardener or have toxines have any thing to do with it? CHEERS. —Preceding unsigned comment added by 82.20.40.20 (talk) 19:31, 23 June 2008 (UTC)

I think the layers of petals are smothering the plants by denying them of sunlight. I suggest that you put all those petals in a compost pit.--Lenticel ^(talk) 23:37, 23 June 2008 (UTC)

And be sure to wear thick gloves, so you don't absorb toxins through the skin. I don't know about this plant, but tobacco workers can absorb toxic levels of nicotine that way. StuRat (talk) 03:58, 24 June 2008 (UTC)

Stanovoi Mountains vs Stanovoi Range

Please see Talk:Anadyr River. Is there a difference between the Stanovoi Mountains in Chukotka Autonomous Okrug and the Stanovoi Range in (well parts of them are, anyway) Amur Oblast? Since the river article "Stanovoi mountains" thing came from the 1911 Encyclopedia Britannica, it could just be that the names changed or became more specific. A Google search thew up some JSTOR links, but I can't see what they are saying. Can anyone help? Carcharoth (talk) 18:04, 22 June 2008 (UTC)

I only took a brief cursory look at both articles, the talk page you mentioned, and watershed maps of the Amur, Lena, and Anadyr rivers, but you might try adding a merge tag to the head of one or both articles, and find out if any objections to the merge appear on the talk pages of the articles. I'm from the western hemisphere and not much of a world traveler, so I hesitate to add the merge tags myself. --arkuat (talk) 04:44, 23 June 2008 (UTC)

Oh, Stanovoi Mountains is already a redirect to Stanovoi Range. No merge needed. But what I'm trying to find out is if there is any remote reason why the 1911 EB would have said "Stanovoi mountains" for the Anadyr River. Given that all the 1911 EB authors are dead, I might have a problem finding this out. Are the watershed maps online? Carcharoth (talk) 11:38, 23 June 2008 (UTC)

Well, now I'm embarrassed that my brief cursory look didn't disclose to me that I was looking at the exact same article under different names, but yes, when I looked at Amur River, Lena River, and Anadyr River, I did find all three watershed maps. For the Amur, you need to scroll down a bit to find the map. --arkuat (talk) 07:30, 24 June 2008 (UTC)

Survival in depopulated world

Suppose, mankind suddenly disappeared and either only me or me and one more person are left (or me and few persons to help). Specifically, how long power and water supply (and availability of internet) would last (may be depending on country)? And how long is it possible to maintain common life (alone, as in I'm Legend or two together). --85.132.14.38 (talk) 21:48, 22 June 2008 (UTC)

Water? If you're talking about tap supplies it's variable, but bottled water would pretty much be indefinite. In the long term your main problem would be developing a major medical condition or sustaining a major injury. Exxolon (talk) 22:21, 22 June 2008 (UTC)

The power supply would shut down in most places in a couple of days after the event that wiped out the rest of humanity. Most power stations (certain hydroelectric plants aside) need pretty much constant supervision. Unless you had a petrol generator, of course - which I guess you could probably keep running for many years, if you went out and gathered/safely stored as much fuel as possible in the early days. Water would be reasonably easy, provided that whatever caused the end of the world didn't toxify it. If the worst came to the worst, you could gather rainwater. Presuming that you're a reasonably capable man with reasonable physical health who knows how to make fire, hunt, gather and cultivate, you could probably live to a reasonable age if you kept your wits about you and avoided major injuries and getting eaten by wild animals (hint - find guns ASAP). I'd guess that it'd be illness that'd get you in the end. --Kurt Shaped Box (talk) 22:36, 22 June 2008 (UTC)

Presuming that you're a reasonably capable man... Or woman! Rockpocket 06:42, 23 June 2008 (UTC)

Or suicide Nil Einne (talk) 22:46, 22 June 2008 (UTC)

Especially if the other survivor is Carrot Top. Clarityfiend (talk) 03:51, 23 June 2008 (UTC)

You may want to read "The World Without Us" (the article and the book). It discusses what would happen if suddenly all the humans disappeared, including what would happen to infrastructure like power and water. -- 128.104.112.147 (talk) 23:05, 22 June 2008 (UTC)

Personally, I would collect some solar panels and storage batteries, or locate your residence at a small hydroelectric plant. These could furnish power for many years. I would not expect a fossil or nuclear plant to operate for more than a few days without highly skilled operators on site. Human life without any modern technology should last perhaps for many years, until you need medicine or surgery to correct some medical attention, or until some predatory animal or accident does you in. Edison (talk) 02:56, 23 June 2008 (UTC)

Or until you are eaten by zombies (such as appear in I Am Legend)... Which illustrates the general point that your survival and the conditions available to you may be strongly dependent on the reasons for the collapse of humanity in the first place. Dragons flight (talk) 03:15, 23 June 2008 (UTC)

If you are interested in fiction with this theme, try the book Earth Abides. StuRat (talk) 11:22, 23 June 2008 (UTC)

I mean, we've only practically had electricity and tap water for about 200 years or so, and plumbing for only about 2000 years. Humans are pretty versatile creatures and we need neither power nor clean water to survive or entertain ourselves. If you were the only person to survive this disaster, I think your main challenge would be keeping your sanity. --Shaggorama (talk) 06:58, 24 June 2008 (UTC)

Creation of an organism

Can a biological organism (e.g. humans) be created completely from DNA as of today? If not, what else other than DNA do we need to create a complete human being? If yes, has this been done? If not, why has this not been done? Is it because of ethical issues or some other scientific issues? Also, if it is not possible to create humans completely from DNA alone, are there other organisms which can be readily created from DNA only? Thanks - DSachan (talk) 22:56, 22 June 2008 (UTC)

No, nothing can be created from DNA alone. At best, reproductive cloning can take DNA from one cell and implant it into an embryo and have the embryo grow up with that DNA. (And even that probably ignores mitochondrial DNA). Which gives some indication of what else is needed: to "grow" something you need all of the extra wetware of a fertilized egg and it needs to be in a suitable environment (read: a womb) to grow in. Human cloning has not yet been known to be successfully done (for both ethical and technical reasons), but there's no reason it shouldn't be feasible someday. --98.217.8.46 (talk) 23:49, 22 June 2008 (UTC)

Thanks, But I was wondering why this cannot be done just by using DNA, when it has all the information that we need to build a human. Can't we create the artificial conditions of womb in the lab? Isn't it just a technological limitation rather than the scientific one. What factor exactly does not allow us to do that? - DSachan (talk) 01:37, 23 June 2008 (UTC)

I think we have ethical limitations rather than technical ones. Biotechnology has improved in such breakneck speeds that ethics can't keep up with it.-Lenticel ^(talk) 02:00, 23 June 2008 (UTC)

You can't create a human from human DNA alone. You need cytoplasm, a cell membrane, some organelles, and all that good stuff. Otherwise it's just a blob of DNA floating around with no ability to replicate or do anything helpful. -- Consumed Crustacean (talk) 02:24, 23 June 2008 (UTC)

Doesn't DNA also have the code to produce the Cytoplasm, cell membrane and all other random stuff. I am not sure about that. Also [8] says that mouse embryonic stem cells (and hence potentially whole mouse) have been created without using female mouse eggs. But says this is not yet possible for humans. In humans, adult skin cells rather than sperms have already been successfully used to create embryonic stem cells but only with the help of female eggs. I think female cells have lot of stuff which male cells don't have or have in less amount as mitochondrial DNA as said above, so they might be needed. So, was it not in the case of mice and why are researchers hopeful that they can create adult human embryonic stem cells without using eggs? Also, we need womb to grow the embryo, can't these biological conditions be created in lab, I just want to know the technical limitations that we are facing as of 2008? DSachan (talk) 02:39, 23 June 2008 (UTC)

Right. It's something of a modern myth that DNA is the one-and-only important thing relating to the "secret of life". There are a lot of other parts of the cell too. The DNA is a sort of master celluar plan. It only works in the context of a cell. (Barring things like simple viruses.) It's just a complicated little acid—just as a computer program is a bunch of letters. Without an interpreter and an environment in which to work, it is just chemical information. In any case it is also becoming more and more evidence that the idea as just "code" floating in space and in isolation is very, very incomplete; even the central dogma is incomplete in many ways. There is a lot more back-and-forth between different parts of the cell and how it interprets DNA (see epigenetics). DNA in a vacuum doesn't mean very much. It's vitally important for life on earth, but that's not enough—it is necessary, but not sufficient. --98.217.8.46 (talk) 02:33, 23 June 2008 (UTC)

DNA provides the plans for all the proteins and other goodies necessary for life. But in order to arrive at a functional living thing you also need machinery to process that DNA and create the right proteins in the right mix. Currently, the only way to accomplish that is to embed the DNA in a cell that already has ribosomes and various other organelles to provide a foundation on which that DNA can operate. Though the DNA tells you how to build more of those organelles, it can only begin to operate if some of those organelles are already available. In normal sexual reproduction the mother provides the egg cell with the initial machinery that allows the newly combined DNA to get started. Various laboratory experiments have had some success with embedding new DNA in various other types of cells and getting the DNA to express itself, but thus far there is always a significant amount of cellular machinery that must be provided in order to produce a viable cell. Dragons flight (talk) 02:55, 23 June 2008 (UTC)

Here's an analogy that isn't perfect and may or may not help: Suppose I drop you on the moon, along with an exquisitely clearly written description of how to build the spacesuit you'll need to survive there. Now, no matter how good your reading, fabricating, and breath-holding skills are, you're probably not going to make it, because you're not likely to find the hardware store you need to buy the raw materials, the lathe and other tools you'd need to fabricate the suit, or an electrical outlet to plug the tools into.

Now, you may object that these are "merely technical limitations", but they're huge technical limitations. Even if we have a perfect DNA blueprint of a human being, growing an actual human being from those instructions would require solving at least half a dozen other big problems, each of them as hard to solve (or harder) than obtaining that blueprint was in the first place. —Steve Summit (talk) 03:00, 23 June 2008 (UTC)

Yes, I am getting the point. Damn, human body is amazingly complex. We have a long to go to fully understand this extra-complicated machine. Can anybody have possibly any idea that if we were to devise a scale between let's say 1 to 100, where 1 is we understand nothing about human body and 100 is we understand everything about it and can do whatever we want, can control all the diseases, all the body reactions or manipulate them, then where do we possibly stand today in terms of understanding of human body? Just a rough idea will be nice. Would it be around 40-50 or more or less? DSachan (talk) 03:14, 23 June 2008 (UTC)

Obviously an impossible and highly opinionated question! But my own opinion is that we're probably somewhere in the 70's. There's a lot we don't know, but there's an insane amount we *do* know, and there's stuff that's absolutely amazing, or absolutely frightening (or both) that we're about to be able to actually do. I'm guessing that some really science-fictiony stuff will become available (though it will be impossibly expensive) within the next 20-30 years. In particular, I'm guessing that both a practical brain-computer interface and some genuine anti-aging techniques will be developed just too late for me to take advantage of them. :-( —Steve Summit (talk) 03:28, 23 June 2008 (UTC)

Well, looking at the frenetic pace of research, anti aging techniques seem to be just few decades away I guess. Maybe 3 decades, or maybe 4, but not more. Don't be so sad, Steve. :) - DSachan (talk) 05:42, 23 June 2008 (UTC)

That is very optimistic. I'm afraid that AI/anti-aging/etc. will remain always "just around the corner", at least for the foreseeable future. I'm not sure what you mean by "brain-computer interface", but if you mean mind uploading, I personally doubt the grandchildren of anyone living today will live to see it. However, this isn't based on anythin g but a knowledge of how many predictions (flying cars/colonies on Mars/synthetic food pills/nuclear fusion by 2000) have failed to come true, and the fact that phrenology promised many of the same breakthroughs as modern neuroscience and was widely accepted in its own time, yet is now known to be worthless. I really don't expect any more huge medical breakthroughs (on the order of Pasteur's discoveries, for example) until we have nanotech to work with. Vultur (talk) 18:36, 24 June 2008 (UTC)

By "brain-computer interface" I mean something you can stick in or on your skull that will let you interact with a computer in a linguistic sort of way, without relying on a conventional keyboard or screen interacting with your fingers and eyes. There've been promising results in this area recently, though mostly restricted to control of artificial limbs.

I believe that this communication will take the form of a brand-new language, optimized for whatever "sweet spot" there is between what new language-like processing we discover our brains can do based on faint electrical stimuli directly within it, and whatever computer processing we can reasonably devise that's compatible with it. I believe that this new language, like any language, will be most easily learned by children, such that only the generations that grow up after the technology has been realized will ever be fully fluent with it. —Steve Summit (talk) 03:34, 26 June 2008 (UTC)

I'm surprised no one has mentioned this yet. Check the article on synthetic life which covers this. We haven't even managed single cell life yet, so extremely complicated multi-cellular mammals like humans are a long way off especially bearing in mind cloning is still rather difficult to do in mammals. Craig Venter has been interested in this for a while now Nil Einne (talk) 05:54, 23 June 2008 (UTC)

Of course, we've been trying this for a few decades while Earth has existed for 4.5 billion years. It takes time. Imagine Reason (talk) 03:19, 24 June 2008 (UTC)

This isn't quite what you're looking for, but you may find it interesting: scientists assembled a polio virus from scratch using its published genome sequence. That work was done right across the hall from me at Stony Brook Uinversity. – ClockworkSoul 19:44, 23 June 2008 (UTC)

I liked Consumed Crustacean's answer: DNA may provide the information, but does not provide the machinery or environment. Moreover, DNA alone is still missing a very important peice: your mitochondria have their own DNA which is not considered to be part of the human genome. --Shaggorama (talk) 06:50, 24 June 2008 (UTC)

Green stuff on fence

When we begin preparing our back yard for spring we always find that our wooden fence (painted white) has some green substance growing on the upper sections. I presume it's some sort of algae and the only way to remove it is bleaching. Does anyone have knowledge of what this stuff is? What does it eat and how does it spread itself across my fence? I live in the Northeastern United States. —Preceding unsigned comment added by 151.203.104.169 (talk) 23:57, 22 June 2008 (UTC)

Probably lichen. A symbiosis that consumes sunlight as well as nutrients and water from aerosols, dust, and rain. ---Sluzzelin talk 01:01, 23 June 2008 (UTC)

I'm likin' that answer, but it could also be moss. Lichen is usually light green while moss is dark green. Click on the pic found here to see a visual comparison of the two. StuRat (talk) 10:59, 23 June 2008 (UTC)

If you live in a high-humidity area, it is common for little green things to grow here and there (on fences, walls, abandoned vehicles, slow dogs...) I never remember the term, but there is a type of moss-like plant that gets all of its water from the high-humidity air. I live on the southern U.S. coast, so my pretty white fence and porch rails are prone to turning green. I've experimented and found that Tylex gets rid of the green, brightens the white, and keeps the green from returning for a few months. Bleach gets rid of the green, but it comes back in a week or so. -- kainaw™ 11:47, 23 June 2008 (UTC)

Um this Tylex? Won't the most effective thing be to paint the fence green, or perhaps black? Nil Einne (talk) 14:05, 23 June 2008 (UTC)

I think he means Tilex. -- Coneslayer (talk) 14:14, 23 June 2008 (UTC)