Wikipedia:Reference desk/Archives/Science/2012 August 16

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August 16

How are the life cycles of Mollusks and Insects alike?

How are the life cycles of Mollusks and Insects alike? — Preceding unsigned comment added by 175.140.183.44 (talk) 00:51, 16 August 2012 (UTC)

See Insect#Reproduction_and_development and Mollusca#Reproduction. 203.27.72.5 (talk) 01:14, 16 August 2012 (UTC)

Why, do you have crabs ? ...or perhaps an unfinished homework assignment ? StuRat (talk) 01:35, 16 August 2012 (UTC)

Very little at all that they do not share with all animalia, except for the fact that they lay eggs and have protostome development. μηδείς (talk) 02:13, 16 August 2012 (UTC)

For starters, they're born (or hatched or whatever) and eventually die. ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:55, 16 August 2012 (UTC)

As usual Bugs, you've hit the nail right on the head. I'm sure that the OP will be impressed by your insightful and erudite answer. Alansplodge (talk) 18:15, 16 August 2012 (UTC)

I do what I can. Next I expect the OP to ask why a raven is like a writing desk. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:53, 16 August 2012 (UTC)

Both insects and mollusks belong to Protostomia and Bilateria. However insects are in the Ecdysozoa superphyllum with mollusks in Lophotrochozoa. In terms of lifecycle they lay eggs, grow some kind of embryo, hatch, and mate. Graeme Bartlett (talk) 09:53, 17 August 2012 (UTC)

Loch Ness monster

What do scientists have to say about the Loch Ness Monster now, after this new photo? Bubba73 ^{You talkin' to me?} 03:13, 16 August 2012 (UTC)

"Wow, yet another meaningless, fuzzy photo". StuRat (talk) 03:59, 16 August 2012 (UTC)

And he saw it for 5-10 minutes - it would be nice to have a sequence of photos. Bubba73 ^{You talkin' to me?} 04:35, 16 August 2012 (UTC)

Bearing in mind that "extraordinary claims require extraordinary evidence", I'd say we need a chunk of Nessie herself, for DNA testing, at the very least. I look forward to that day, if only because it will cause them to play one of my favorite songs by The Police again. StuRat (talk) 04:46, 16 August 2012 (UTC)

My award for the most incorrect maxim is the "Extraordinary claims..." one, closely followed by "What you can't see, can't hurt you. Those who are totally partisan about some notion will "require" massive evidence to the contrary to overturn their prejudices. Logically speaking, the amount and quality of evidence to refute (or corroborate) any theory should be the same, regardless of how loyal we are to the one held at the time. To say that one needs "extraordiany" evidence for much-favoured theories of long-standing is just another way of putting a tariff on their rivals. Myles325a (talk) 05:44, 16 August 2012 (UTC)

Not following you at all. That a population of dinosaurs could exist in Loch Ness is an extraordinary claim. Fuzzy photos are not extraordinary evidence. A claim which is not extraordinary, like that there is a newly discovered species of purple fruit fly deep in the Amazon, wouldn't need such extraordinary evidence. A simple photo might be enough (although it would need to be clearer than those Nessie photos). StuRat (talk) 06:13, 16 August 2012 (UTC)

You have just restated your initial case, with no response to mine. My take is that in a formal way, labelling claims as "extraordinary" or "plausible" or "obvious" is to beg the question and alrady accord them a status that should be argued for, not applied at the outset. We should be just as satisfied / dissatisfied with evidence for a new species of fruitfly / dinosaurs in Lock Ness, and not expect the former to be "extraordinary" while the latter can just be "routine". That is the way entrenched theories retain their status, they are grandfathered in. This is an important point in the Philosophy of Empiricism, and is well-expounded by Karl Popper. the foremost philosopher of the Logic of Scientific Discovery. Myles325a (talk) 07:00, 16 August 2012 (UTC)

A better way to phrase the maxim would be to ask, what about the world as we know it would have to be different to make this endpoint seem more likely than any other? To have a dinosaur-like creature in a lake of that size would require quite a lot of jumps, mainly: 1. that this creature has survived for a long time without leaving significant evidence, despite all of the troublesome ecological things that would imply; 2. that somehow a breeding population of these creatures has survived long enough to significantly overlap with human occupation of the area, without leaving significant evidence. We contrast that with the steps that require these things to not exist: 1. human beings are superstitious, easily fooled, and/or have a variety of reasons for misleading one another. The latter narrative is easy to imagine — it requires no leaps whatsoever, since we have ample evidence of this sort of thing. The former narrative is hard to imagine: it would require quite a lot of unexpected junctures (unexpected in the sense that we don't have similar evidence). This isn't open and shut logic, but it does seem to suggest that if one is going to believe in the other narrative, and think it likely, then one would require fairly solid evidence in favor of it. "Extraordinary evidence" is just a reworking of Occam's Razor, and is as such just heuristic, but it is a useful heuristic. There are lots of things which, taken in isolation of the narratives that lead to them, sound fantastical. The notion that someone put an SUV-sized robot on Mars would be a completely fanciful, ridiculous idea, were there not a very well-documented chain of events leading up to it. (In any case, without wanting to appeal to authority, no philosophers of science think Popper's discussion of any of this is very adequate. It is popular mainly amongst people who do not understand it very well — which is to say, science popularizers or partisans — not philosophers, historians, or philosophically-minded scientists.) --Mr.98 (talk) 17:35, 16 August 2012 (UTC)

I agree with most of your comment but I wouldn't dismiss Popper so easily. I took an undergraduate unit in philosphy of science when I was doing my BSc and a large chunk of the curriculum was based on his work. 203.27.72.5 (talk) 23:17, 16 August 2012 (UTC)

He's an important figure to know, and was very influential, but once you get beyond the introduction to the philosophy of science, most of what remains is about how completely incorrect he was in articulating how science works in practice (no scientist acts like a Popperian actor, and most of them do exactly the opposite of what he says they should be doing) or even could work (even something as seemingly obvious as falsifiability becomes maddeningly difficult to reconcile with how actual practice would go down). There are probably a few rogue Popperians around but they are far more rare than the people who recognize that his stuff has big problems and doesn't really do what he thought it did. But this is a separate issue. --Mr.98 (talk) 00:46, 17 August 2012 (UTC)

In an ideal world, perhaps. In the real world, there are many people who would fake Nessie, just for a bit of publicity and/or business, but few who would fake the purple fruit fly in the Amazon, as it's existence is hardly going to boost the tourism industry there. If you require the same standard for both, then you will either end up accepting many hoaxes involving Nessie, Sasquatch, etc., as proof of their existence, and/or rejecting perfectly plausible evidence of lesser species.

This reminds me of the similar problem in math (we have an article on it, but I forget the name). "If somebody hands you what he claims to be a fair coin, and you then toss heads 200 times in a row, what are the chances of it happening again, if you toss it another 200 times ?" Well, mathematically, the chances of the first 200 times being heads were 2²⁰⁰, or some 1.6×10⁶⁰, and the odds of the second 200 tosses being heads would be the same. However, it's perfectly absurd, in the real world, to believe that it's a fair coin, after getting 200 heads in 200 tosses. Thus, once we reject this assertion, the probability of tossing another 200 heads in a row is far higher than the theoretical math would indicate. StuRat (talk) 07:55, 16 August 2012 (UTC)

Popper's views about how science works are kind of outdated. You might be interested in the work of Thomas Kuhn. Consensus plays an important role in the functioning of science. If all hypotheses were given equal weight until disproved, nothing would ever get done. There are too many possible hypotheses, and not enough time to refute them all. Requiring stronger evidence to support large changes in current understanding is one of several tools for getting around this problem.--Srleffler (talk) 06:15, 18 August 2012 (UTC)

The conflict between Popper's principles and the practical principles that permit Wikipedia to function (see WP:EXCEPTIONAL) is kind of fascinating. (One major difference is that Wikipedia isn't interested in verisimilitude, only notability and reliable published sources, and will often present multiple conflicting conjectures if they are all notable and published.) I expect there's some re-phasing of the maxim that could allow compatibility with Popper. How about this: a claim which, if true, would cause a radical and wide-ranging shift in our ideas, will prompt a great deal of criticism. Though, of course, cutting to the chase and beginning the actual criticism seems better than saying the rather vacuous maxim. The maxim may have some use in the form "don't brush aside obvious criticisms".  Card Zero  (talk) 10:29, 16 August 2012 (UTC)

Occam's acusector: Why say versiml... verlers... verismirl... vrslrmrtd when you can just say truthiness! -- OBSIDIAN†SOUL 07:36, 18 August 2012 (UTC)

"Spirits in a Material World"? Dismas|^(talk) 05:02, 16 August 2012 (UTC)

Not quite: [1]. StuRat (talk) 05:14, 16 August 2012 (UTC)

Not enough surface ripples for a beast of that suppossed displacement. SkyMachine ⁽⁺⁺⁾ 04:49, 16 August 2012 (UTC)

Maybe it was shagged out after having a long yodel (These beasties yodel, did you know that?)

"George Edwards takes his boat, “Nessie Hunter,” out onto Loch Ness nearly every day, often with tourists" conflict of interest, anybody? 203.27.72.5 (talk) 05:22, 16 August 2012 (UTC)

I've had a close look at that photo, and in all humility, I am something of an expert in this field. My opinion is that that object would have caused the person who produced it considerable pain in the anal region. Myles325a (talk) 05:34, 16 August 2012 (UTC)

You're an expert in the field of butthurt? Someguy1221 (talk) 06:16, 16 August 2012 (UTC)

The size and movement (or lack thereof) in the ripples in the water suggest to me that this is a rather small object that's basically floating - as with the famous 1930s photo of Nessie that proved to be a toy submarine with a fake neck and head attached. ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:53, 16 August 2012 (UTC)

As another self-considered quasi-expert (well, a member of the CFZ, anyway), I disagree that the photo has "proved" to be a toy submarine. It may be true, but is based on an alleged deathbed confession of a supposed conspirator reported many years after said death: either the deathbed confession itself or the very belated report of it may themselves have been jokes/hoaxes, as there is (to my knowledge) no corroborative evidence for either. Personally, I've always thought that the photo in question looks suspiciously like a slightly motion-blurred Diver (aka loon). {The poster formerly known as 87.81.230.195} — Preceding unsigned comment added by 84.21.143.150 (talk) 13:11, 16 August 2012 (UTC)

In the full photo, not the cropped version, it's clear that the "monster" is very small. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:51, 16 August 2012 (UTC)

A dead fish. AndyTheGrump (talk) 14:02, 16 August 2012 (UTC)

That was what it looked like to me at first too. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:51, 16 August 2012 (UTC)

And, in any case, Weekly World News used to publish much better photos of the Loch Ness monster.--pma 18:36, 16 August 2012 (UTC)

It's a Skarasen whoviensis. μηδείς (talk) 21:26, 17 August 2012 (UTC)

Does Neanderthal DNA show nature of sexual unions?

Like many others I was fascinated to learn that research had shown that Sapiens and Neanderthals had reproduced, and so there is some Neanderthal DNA in our chromosomes. It is the usual case that a dominant culture takes the females of the weaker culture for breeding purposes. I wonder if there are signs on our X chromosome and in the mitochondria that might show the non-symmetric nature of such sexual unions. (Dominant cultures might also take male slaves from those they defeated or colonised, but I am assuming that such practices came much later). Myles325a (talk) 05:30, 16 August 2012 (UTC)

Research related to the Neanderthal genome project has not revealed any evidence of Neanderthal mitochondrial DNA in humans. Comparison of human and Neanderthal genomes shows the mixture of genes is similar across all chromosomes. This doesn't rule out that there was a particular mating pair (male human versus female human) that dominated the sexual interaction between the two species, but it does suggest that such interactions were rare relative to human-human matings. Unfortunately, the three Neanderthals used in this project were all female, so the researchers did not have any Neanderthal Y chromosomes to use as a reference. If we had such chromosomes, answering your question might be possible. The presence of Neanderthal Y in modern humans would show that Neanderthal-male to human-female matings occured, and its suspicious absence would suggest that the interspecies matings were the reverse. Someguy1221 (talk) 06:12, 16 August 2012 (UTC)

The latest research seems to suggest that such matings may not have taken place, and that the presence of DNA similarities may rather have arisen from shared ancestry. Ghmyrtle (talk) 08:04, 16 August 2012 (UTC)

I think it is fair to say that this is an unresolved question with some strongly held opinions and a lack of sufficient data. Rmhermen (talk) 14:46, 16 August 2012 (UTC)

what was there before the BIGBANG ?

KINDLY GET ME THE ANSWER FOR,WHAT WAS THERE BEFORE THE BIGBANG. — Preceding unsigned comment added by 117.213.57.60 (talk) 05:37, 16 August 2012 (UTC)

That was the "Age of the Stuck Caps Lock". The BIGBANG, as you put it, began when supersymmetry broke the fusion between Caps and Lower Case, and set both of those free to interact with each other, creating title case, and so on. Read all about it here: Big bang— Preceding unsigned comment added by Myles325a (talk • contribs)

As far as I know, time began with the Big Bang, so it makes no sense to ask what happened "before" the Big Bang. It would be like incorrectly assuming the world is flat and asking what is over the edge of the world. Plasmic Physics (talk) 05:55, 16 August 2012 (UTC)

Snarkiness aside, no one knows. As you will read in the linked article, theories range from "another universe" to "nothing" and "something else". There is no solid evidence for any pre-big-bang theory. Someguy1221 (talk) 05:56, 16 August 2012 (UTC)

Possibly that is where the God of the gaps resides. SkyMachine ⁽⁺⁺⁾ 06:33, 16 August 2012 (UTC)

The BIGFOREPLAY? Clarityfiend (talk) 10:17, 16 August 2012 (UTC)

No one knows, and you should be skeptical of anyone who claims to know. In religious terms, this question is equivalent to 'what made god.' However, your question would be much more useful if you instead ask "What could have existed before the big bang?" Some possibilities include Absolutely Nothing (See the lecture on youtube, "A Universe from Nothing" by Lawrence Krauss here), and a previous universe that collapsed (went though a Big Crunch). Or, of course, "Anything else." The problem with any sort of scientific evaluation of this question is that almost by definition, there would be no physical evidence or remaining clues or pieces of whatever there was, so there is no evidence to make a judgement in any direction. For all we could tell, "A pink fluffy easter bunny" could be what there was before the big bang, and there's not a shred of evidence in this universe that could disprove it. Ehryk (talk) 10:37, 17 August 2012 (UTC)

The Big Bang itself is a scientific theory based on observed evidence, i.e. it's not a "fact" as such, but rather it's our best educated-guess for how the universe began. As you indicate, there is no known evidence for what might have occurred, if anything, before the Big Bang. So we can only hypothesize, at best. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:19, 17 August 2012 (UTC)

The Big Bang is like Zeno's paradoxes. Go to a second after the Big Bang, compare it to things a tenth of a second after the Big Bang, and everything was massively different. The super-hot particles have undergone massive changes in their overall physics in that time, interacted with countless partners under the absurdly high heat and pressure, moved a fair amount of the way across the "small" cosmos of that time. And the same is true if you compare 1/10 to 1/100, 1/100 to 1/1000 ... any time you compare a 10x difference in the age of the universe, it's going to matter. Right up to the point where we can't make any coherent comment on what the physics would have been like at all. And the universe was still doing things before that, we just don't know what. Wnt (talk) 04:39, 20 August 2012 (UTC)

blueshift and redshift.

If something is blueshifted does it appear visually blue or is it just that the spectral lines sre shifted to the blue end of the spectrum?

If it doesn't appear visually blue is there a point where if blueshifted enough that it would appear visually blue? — Preceding unsigned comment added by 92.23.113.145 (talk) 11:02, 16 August 2012 (UTC)

It depends on the amount of the blueshift, and on the original colour, but yes, receding approaching objects appear (marginally) bluer than they really are. This is noticeable in distant stars that often appear blue. For a moderate blueshift, red might appear yellow, yellow might appear green etc. (See next comment -- my brain must have slipped out of gear! ) This is most unlikely to ever be observed. Dbfirs 11:28, 16 August 2012 (UTC)

Stars within our Galaxy recede by no more than, say, 300 km/s. This induces a redshift $\Delta \lambda /\lambda \approx v/c$ of about 0.1 per cent. That is by far not enough to be noticeable visually; you need a spectrograph to measure the shift of absorption or (rarely in stars) emission lines. You may be thinking of galaxies, and yes, there are highly red(!)shifted galaxies that appear blue. That colour has nothing to do with the redshift, it is due to the fact that these galaxies contain lots of young stars which have a spectral energy distribution that increases towards the ultraviolet. The visual appearance depends on the spectral energy distribution of an object's light, the red- or blueshift is a secondary effect to the visual appearance, which is not uniquely "red" or "blue" (it is defined as a shift of the spectrum towards longer ("redder") or shorter ("bluer") wavelengths). --Wrongfilter (talk) 11:59, 16 August 2012 (UTC)

Thanks for the gentle correction to the rubbish I wrote. I've partially corrected it. Dbfirs 22:00, 16 August 2012 (UTC)

See blueshift, red shift and Doppler effect. What the answerers above have danced around but not explicity mentioned is that it is not restricted to visible light. The words blueshift and redshift derive from the appearance of the effect when it is in the visible spectrum, but they generally refer to any apparent shortening or lengthening of electromagnetic waves due to relative motion between the source and observer. This may be X-ray to gamma, or microwave to radio, or red light to blue light, or an infinite number of other possibilities. 203.27.72.5 (talk) 23:35, 16 August 2012 (UTC)

The affect on the visible colour is going to depend on the initial colour, including what is happening outside the visible spectrum. Depending on how large the blueshift is, the visible light you see may have started out as infrared or even microwaves (although that would be a lot of blueshift - you would probably need a black hole to be involved or something to get that). The object will only actually appear bluer if the amount of the blueshift is such that its previous peak moves into the blue part of the spectrum. --Tango (talk) 12:04, 17 August 2012 (UTC)

war planes

how come libya was so inaccurate dropping bombs during the Libyan civil war. I remember several instances of video footage of a Libyan bomber plane coming in dropping bombs on rebels and they wouldn't even make it within 100 yards of the target. However, during the current Syrian conflict The government who is using many of the same fighter planes has been deadly accurate with their bombs.--Wrk678 (talk) 13:33, 16 August 2012 (UTC)

Training? Better munitions? Good military intelligence? More willingness by the pilots to bomb their countrymen? Less crosswind? There are any number of reasons why outcomes are not identical when you vary the starting conditions. — Lomn 13:42, 16 August 2012 (UTC)

my first though would be training but there are actually some "training films" of old MIG jets and they seem fairly easy to bomb with and quite accurate. The strange thing is the Libyan army was known for being very accurate with their mortars and artillery which they demonstrated well during the uprising. --Wrk678 (talk) 14:32, 16 August 2012 (UTC)

Training films (presumably assembled by the very best pilots under ideal non-combat conditions) and artillery (which has nothing whatsoever to do with flying planes or training pilots to fly planes) are not compelling counterexamples. — Lomn 15:39, 16 August 2012 (UTC)

Precision munitions leave little work up to pilot skill. In the jet era, the aerial advantage has shifted from the country with the best pilots to the countryparticipant-combatant with the best economy, research-and-development infrastructure, and (in the case of "other-than-superpower" air forces), the ability to acquire quality imported equipment and munitions. So, this become an issue of international politics and arms trade; logistics and supply-chain management. For in-depth, public-disclosed discussion of the Syrian air force and its capabilities in 2012, you may find this August 1 testimony to Congress by RAND expert James Dobbins enlightening.

And, while perusing the RAND website, you may also find their 2012 Air Force Materiel Command Reorganization Report informative, if you want to establish a background level of knowledge about modern air force supply-chain management. Nimur (talk) 17:58, 16 August 2012 (UTC)

Maybe the pilots were tuned into the revolution and it was a foregone conclusion that it was time for a change, so they missed on purpose.165.212.189.187 (talk) 18:04, 16 August 2012 (UTC)
I don't think they were as bad as you might think overall. According to this article, they managed to push back a rebel advance along the north coast with airstrikes. Apparently, these attacks were more accurate then previously seen. According to the wikipedia article on the Libyan Air Force, they even managed a successful bombing mission under the no fly zone, though it cited a blog as its source. 203.27.72.5 (talk) 02:22, 17 August 2012 (UTC)

asenapine

hai, pl anybody give me information regarding teratogenic effect of asenapine. — Preceding unsigned comment added by 203.6.211.98 (talk) 13:51, 16 August 2012 (UTC)

Product information about Sycrest, which is one branded form of asenapine, is here. It says "There are no adequate data from the use of Sycrest in pregnant women. Asenapine was not teratogenic in animal studies. Maternal and embryo toxic effects were found in animal studies" and gives further details of the animal effects. This site says that in the US, the Food and Drug Administration classifies asenapine as a "C" in terms of its teratogenic effect, which means "Animal studies indicate a risk but there is no safety data in humans". Aside from publicly available documents such as these, we can only refer you to a qualified medical advisor for further information, and this is also the advice on the various websites that discuss asenapine use during pregnancy. - Karenjc 15:58, 16 August 2012 (UTC)

How long does it take to go from patent to commercialization?

I am working on a research project and I need some data on how long it takes from the time a patent is filed to the time of first sale or the time of commercialization. I have been looking for a while and haven't really been able to find much except for this paper: http://onlinelibrary.wiley.com/doi/10.1002/smj.643/abstract.

Does anyone know of any other studies or datasets? Thanks. Eiad77 (talk) 14:08, 16 August 2012 (UTC)

Are you asking for an overall average? I suspect it will somewhat depend on what the patent covers. While many patents cover things which have some time to market, the likely steps needed on average will tend to vary. Drugs for example have a number of specific regulatory steps that they need to go through so any patent covering them may have a resonable time between patent and first sale whereas many other patents (software patents for example) may not generally cover things requiring such steps. Nil Einne (talk) 16:34, 16 August 2012 (UTC)

Any data would be better than nothing, but I'd be most interested in engineering patents. Eiad77 (talk) 16:38, 16 August 2012 (UTC)

If the inventor or his company isn't worried about someone else inventing the same thing before the application being filed, sometimes the application isn't sent in until just before commercialization, so the commercialization comes before the patent. Jc3s5h (talk) 17:05, 16 August 2012 (UTC)

Even if they are worried, there is patent pending. --Mr.98 (talk) 17:26, 16 August 2012 (UTC)

"I see his name on so many inventions, that Pat Pending must be a genius !" StuRat (talk) 13:46, 17 August 2012 (UTC)

There is no requirement that one have a patent before marketing a product, and marketing a product does not prejudice a patent application. Perhaps you would need a patent to sell or license the patent rights, but even then, negotiations could proceed before a patent has been granted. Are you just looking for statistics? μηδείς (talk) 17:13, 16 August 2012 (UTC)

They are looking for "data". --Mr.98 (talk) 17:28, 16 August 2012 (UTC)

μηδείς is only right when referring exclusively to the US. Marketing a product is considered a form of disclosure under most jurisdictions, and it is a hindrance to granting a patent. If you are serious about what you are doing get professional legal advise from a patent lawyer. Qpl87 (talk) 16:42, 17 August 2012 (UTC)

I've found it surprisingly difficult to dig up statistics on this, though I am sure it has been studied exhaustively, like most things patent-related. This paper offers a bunch of cherry-picked examples but shows a good way that such a study would be arranged (comparing earliest patent date with date of first sale/release of product), and may prove fruitful for more literature searches. The examples they pick show it is about 3 to 5 years, but I've no idea if that holds when looking at more data. --Mr.98 (talk) 17:26, 16 August 2012 (UTC)

Thanks, a lot! That's pretty useful even if it's not very comprehensive. I have found it surprisingly tricky to find data too. If anyone finds anything similar, let me know! Eiad77 (talk) 17:44, 16 August 2012 (UTC)

I think the reason it's so hard to find data linking the two is because they're not really linked. The company I work for is currently commercializing a new technology that the patents aren't issued for yet. In general, no one else can patent your discoveries, so as long as there's no risk that another company will start using it before you make an application, then you can take your time. Also note that even if your application is successful and the patent is issued, it has happened that a court has declared the patent overly broad and invalidated it. 203.27.72.5 (talk) 23:50, 16 August 2012 (UTC)

It doesn't matter if they're linked — it would still be interesting to know (especially across industries), and there are lots of context in which that information would be useful (e.g. evaluating the effect of a new patent granting on a future earnings potential of a given company). I think you're quite wrong about the time factor not mattering — it really depends on the industry. In big pharma for example the patent clock is not as long in practice as you'd think because of all the testing, and the minute it runs out there will be tons of generics out there. For those guys, the length of time before getting the drug on the market really translates into a lot of money. Anyway, I find it hard to believe this hasn't been studied. Business schools have dredged up data on practically every other patent statistic out there. It is a major field of research. --Mr.98 (talk) 00:37, 17 August 2012 (UTC)

Yes, you're right about it depending on the industry. I was thinking of engineering applications where the patent is only needed to secure your exclusive rights, not as a prerequisite for fulfilling regulatory testing requirements. 203.27.72.5 (talk)

I may be stating the blindingly obvious here, but if you are trying to determine an average for the time it takes "to go from patent to commercialization", the answer is either infinity, or at least not a meaningful number at all. The majority of patents are never "commercialized". Sadly, far too many people seem to think that a patent is a guaranteed route to profitability. I think you need to look at it backwards - if a patent proves successful, how much earlier on average was it taken out? AndyTheGrump (talk) 02:20, 17 August 2012 (UTC)

This is true. I realize that a very small percentage of patents are ever commercialized. I guess if I were to be really precise, the question I am asking is: "For patents which are commercialized, what is the average time period between when the patent is filed and commercialization?" Eiad77 (talk) 13:10, 17 August 2012 (UTC)

current

laser transmit the current? it's possible? — Preceding unsigned comment added by K.jayen (talk • contribs) 16:22, 16 August 2012 (UTC)

Yes, see electrolaser.  Card Zero  (talk) 17:09, 16 August 2012 (UTC)

Lasers emit light - electromagnetic waves - and an electromagnetic wave does not carry or move charge. In cases where the wave travels through a region with freely-moving charged particles, the wave and the charge can interact; a current could flow, depending on the situation. But there is a significant difference between a propagating electromagnetic field, and a propagation of electric charge - even if the two phenomena coincide and interact. In some unusual configurations, a laser may cause charge to flow - especially high power lasers that ionize the medium they're in, or are powerful enough to create a plasma by heating the air through which the beam is passes. These are exceptions, not the norm. Nimur (talk) 17:37, 16 August 2012 (UTC)

Perhaps relatedly: Beam-powered_propulsion#Electric_propulsion; Elevator:2010#Beam_Power_Challenge. --Mr.98 (talk) 17:43, 16 August 2012 (UTC)

magnet

iron or something material go to very cooling temperature it's act magnet? — Preceding unsigned comment added by K.jayen (talk • contribs) 16:29, 16 August 2012 (UTC)

You may be thinking of superconducting magnets, in which certain superconductive materials can become magnetic; or the related Meissner effect, where the material "repels" a magnetic field. The classroom example for this effect is usually a ceramic that has been cooled by liquid nitrogen, not iron; though modern investigations have found weak superconductivity effects in all sorts of materials. Nimur (talk) 17:42, 16 August 2012 (UTC)

Orange lights, other colors of LED lights

Because standard 3 lights, yellow lights, red lights, green lights, and white lights and blue lights, where is a common place you find orange LED lights. I heard about purple lights, but where will you likely to see purple LED lights. Is there such thing as brown LED lights or pink lights. I know the blue lights and the white lights well, I just want to know where will you see orange LED lights, is there even such thing as pink LED lights or brown LED lights? I heard they use purple LED lights at concerts, Olympics, where will I see purple LED lights. What other colored LED lights are there?--69.226.44.207 (talk) 20:35, 16 August 2012 (UTC)

The Wikipedia article Light-emitting diode#Colors and materials gives a list of colours and how they are produced. Some colours are more expensive to manufacture. I have some orange LEDs in Christmas lights. I don't know where you might see purple, violet or pink. Violet can be produced naturally, but purple, pink (and presumably brown, though I don't know why anyone would bother) have to be produced artificially by combining colours or adding phosphors, pigments or dyes. Dbfirs 21:39, 16 August 2012 (UTC)

Is amber lights (traffic lights) always yellow lights or is it orange lights. I have somebody told me some traffic lights are orange lights. I just see some traffic lights/ yellow lights look a little golden, I hardly think yellow lights/traffic lights actually look orange.--69.226.44.207 (talk) 23:14, 16 August 2012 (UTC)

Yes, most traffic lights are yellow, but I have seen a few that look rather orange. However, those aren't LEDs. (Does anybody make LED traffic lights ? I'm not sure they would be bright enough.) StuRat (talk) 03:40, 17 August 2012 (UTC)

Yes, in fact they are widespread. See Traffic light. 203.27.72.5 (talk) 04:48, 17 August 2012 (UTC)

I see. However, they don't get hot enough to melt off snow, which might explain why I don't see them here. StuRat (talk) 05:09, 17 August 2012 (UTC)

What a great lead question, I love it! Its like a poem on crack!165.212.189.187 (talk) 14:33, 17 August 2012 (UTC)

I'm not sure where you are Stu, but here in the Canadian Prairies all of the new traffic lights that go up are LED technology, and we nearly spend long enough covered in snow every year to forget what grass looks like. Sometimes a fresh snowfall can accumulate in a pile on the traffic lights on a calm day, but the actual lens is never obscured. BigNate37_(T) 08:03, 18 August 2012 (UTC)

Detroit. We often have road signs which become unreadable when compacted with snow, so I'm surprised this doesn't happen with the LED lights, if they can't melt it. Perhaps your version has a device specifically to heat it on cold days ? StuRat (talk) 09:15, 18 August 2012 (UTC)

Well our traffic lights have visors over each lens, and really that's more to shade the sun so they are somewhat visible even when in direct sunlight. Frankly I'm having trouble understanding how snow would accumulate on the lens in the first place, as they're a vertical (albeit slightly concave) surface. Perhaps it bears mention that our snow is almost always light, fluffy, and dry—when it remains well below freezing for weeks at a time, our snow doesn't stick together anyways (except where it is driven or trod on). We certainly don't have any kind of snow heating going on with our traffic lights or any other city property; that sounds dangerous, it would cause icicles to form above the street. BigNate37_(T) 09:58, 18 August 2012 (UTC)

Actually, traffic lights usually use Fresnel lenses, so they are ever so slightly convex, not concave. 203.27.72.5 (talk) 20:37, 18 August 2012 (UTC)

The conditions that cause vertical signs to be compacted with snow are as follows:

1) It's been quite cold, typically overnight, so the signs are well below freezing.

2) A warm front moves in, bringing snow and raising the air temp to right around freezing. This gives us big juicy flakes that clump together and blow at an angle.

3) When those big flakes hit the face of the sign, they freeze to it, and accumulate, until the sign becomes unreadable. I'd expect the same thing to happen to cold traffic lights, although the visor might help a bit. Also, if slightly warmer, we get freezing rain rather than clumping snow, which can be even worse. StuRat (talk) 10:10, 18 August 2012 (UTC)

I see what you mean, something like [2]. Our metal street signs sometimes see this phenomenon, particularly on the larger ones like stop signs. I've literally never seen it afflict traffic lights, though. Perhaps glass lenses don't have the heat capacity to exhibit such phenomena. BigNate37_(T) 16:03, 18 August 2012 (UTC)

That might explain it. Or maybe they are heated. Note that the heat from traditional traffic lights didn't make them form significant icicles. Presumably the amount of snow that is melted is just insufficient to make much of an icicle. (You normally need a roof's worth.) Here's a pic of an LED light with small icicles, supporting the idea that they are heated: [3]. StuRat (talk) 18:47, 18 August 2012 (UTC)

(LED traffic lights have been common enough to be an easy topic of discussion since at least 2001-2002 [4] [5] although I think a number of places used existing fixtures only replacing the red and green bulbs at first per the earlier links and [6]. As noted in those links some places had already switched many of their lights by 1998-2000. In the past, it may have been fun to play spot the LED traffic light, nowadays in most places it's spot the non LED traffic light.) As for this discussion, evidentally LED traffic lights are widely used in Detroit city proper [7].

During the last seven years, 90% of Detroit’s traffic signal system (approximately 838 intersections) has been upgraded with LED (light emitting diode) and 12” signal heads from 8” incandescent bulbs for improved visibility, reducing energy consumption by almost 90%.

From that and [8] [9] [10] [11] [12], it sounds like it's been happening there and in the wider Michigan area for quite a while (as with most of the world). In fact if you look at [13], there's multiple Energy Efficiency and Conservation Block Grant projects involving LEDs in Michigin, but only one of them seem to be for traffic lights (most of the ones are for parking lights or street lights), I presume because most have already done it for traffic lights.

So while StuRat's experience may be accurate for whatever corner of Detroit they're in, it doesn't sound like it applies to most of Detroit or Michingan. The Road Commission for Oakload County boasts multiple times [14] [15] about being a leader (recognised by the NTSB in 2009) in using LED traffic lights and how they also have a programme for replacement of LED traffic lights with more LED traffic lights (since while they have a long lifespan it isn't infinite) so I guess StuRat doesn't have to go that far if they want to definitely see some LED traffic lights (although as said, it sounds like visiting most other parts of Michigan or Detroit will be enough).

As for the snow problem, an interesting article from the Detroit Times with the title 'New traffic lights too cool' which unfortunately isn't only available on a pay archive (baring one site which is potentially violating copyright so isn't linked) [16] suggests the problem is potentially overblown. It does happen in certain conditions

Bryson said a number of circumstances have to merge for the LEDs to be obstructed by ice or snow. “The wind has to blow at a certain speed and a certain angle to end up in against the lens,” he said. “Plus the snow has to be wet and heavy.

and is usually cleared by compressed air when it's reported. But while a heater was one solution looked at, as of 2009 it wasn't considered desirable and changing the shade was another solution being looked at. Someone from the RCOC (which admittedly as we've established is strongly supportive of LED traffic lights so isn't exactly an unbiased source) suggests having non LED traffic lights with blown bulbs was more common then snowed over LED traffic lights. The source also mentions that no accidents or deaths related to the problem had been reported in Michigan although there had been accidents in other stated (it was written near the end of 2009) and that Franklin (I presume Franklin, Michigan) and Michigan State University had plenty of LED traffic lights.

Nil Einne (talk) 02:55, 19 August 2012 (UTC)

Thanks, Nil. That "clearing with compressed air" idea doesn't sound very practical, to me. They are planning to go out with a cherry-picker in the middle of a blizzard to do that ? This would likely cause as many accidents as it would prevent. StuRat (talk) 03:31, 19 August 2012 (UTC)

Who said anything about going out in the middle of a blizzard to do it? In any case, I can't comment on the practicalities except to say it's apparently what they do as per the source, so I guess it works even if it's not probably not an ideal a long term solution. Although [17] [18] suggests some places brush or scrape it off. Nil Einne (talk) 06:41, 19 August 2012 (UTC)

Well, since snow is likely to be packed into the traffic light during a blizzard, your options are to remove it during that blizzard, or wait until a sunny day, at which time it will probably melt off on it's own. However, in the meantime, there could be quite a few accidents. (If there's one time you want traffic lights to be nice and bright, it's during a blizzard, when visibility is already reduced.) StuRat (talk) 06:54, 19 August 2012 (UTC)

As for a practical use, orange LEDs could serve as a warning indicator between yellow (don't worry about it) and red (evacuate to outside the blast radius immediately). StuRat (talk) 14:37, 17 August 2012 (UTC)

There is no such thing as a brown light. Brown is an artifact of the way the human visual system interprets color in a scene. You can't make a brown spotlight.--Srleffler (talk) 06:21, 18 August 2012 (UTC)

Yes, brown is more of a reflective colour. Pigments and dyes can look brown in reflected light, but it is difficult to get light to look brown when shone through them since almost all of the light will be absorbed. It would be possible to have an LED indicator that looked brown, but not a spotlight that made everything it shone onto look brown. Dbfirs 07:28, 18 August 2012 (UTC)

What are all of you talking about? Brown is simply a negative "luminosity" of orange (where -1 is black, and +1 is white), or dark orange. A brown LED is simply a low power orange LED. Plasmic Physics (talk) 07:54, 18 August 2012 (UTC)

I call that "dark orange" rather than "brown" but perhaps it is just a matter of perception. We all see colour differently. Dbfirs 08:09, 18 August 2012 (UTC)

Yes, PP has a nonstandard def of brown. Here's a page which lists the RGB values for orange as 255,165,0 (no blue) and brown as 165,42,42 (as much blue as green): [19]. StuRat (talk) 09:22, 18 August 2012 (UTC)

Of course, that RGB coordinate represents perfect brown, brown covers the domain of [Hue, Sat, Lum] = [0 < x < 40, 0 < y ≤ 240, 0 < z <120]. Plasmic Physics (talk) 10:58, 18 August 2012 (UTC)

A good example of brown could be [Hue, Sat, Lum] = [20, 240, 60] ≡ [R, G, B] = [128, 64, 0]. Plasmic Physics (talk) 11:02, 18 August 2012 (UTC)

See last year's Where can I get some brown or grey lights for halloween? μηδείς (talk) 03:39, 19 August 2012 (UTC)

Cultural impact of extraterrestrial contact

Cultural impact of extraterrestrial contact

In reading this Wiki article, please explain to me in layman's terms the following:

"Moreover, humans may be an unsuitable food source for extraterrestrials because of marked differences in biochemistry.[3] For example, the "handedness" of molecules used by terrestrial biota may differ from those used by extraterrestrial beings.[39]"

I'm confused by the phrase "Handedness of molecules" Reticuli88 (talk) 20:52, 16 August 2012 (UTC)

It's referring to chirality. Molecules that have the same atoms, but in mirror image arrangements (labeled "right-" and "left-handed"), can behave differently in chemical reactions. Clarityfiend (talk) 20:56, 16 August 2012 (UTC)

How will that affect the extraterrestrial, in layman's terms please?Reticuli88 (talk) 20:59, 16 August 2012 (UTC)

It depends. Some molecules may simply be indigestible, making us good diet food. Others could be poisonous in various ways. See Thalidomide. μηδείς (talk) 21:02, 16 August 2012 (UTC)

It's a plot device that crops up now and again in science fiction stories. Beings stranded on otherwise habitable planets starve to death because the chirality (chemistry) is wrong. (Damon Knight and Rod Serling obviously thought otherwise with "To Serve Man" and "To Serve Man" (The Twilight Zone).) Clarityfiend (talk) 21:10, 16 August 2012 (UTC)

The best story of that ilk is Clarke's 1950 "Technical Error", where it makes a sort of sense, but that doesn't involve aliens. Wnt (talk) 09:23, 17 August 2012 (UTC)

Chirality is important also in Roger Zelazny's Doorways in the Sand. —Tamfang (talk) 02:42, 19 August 2012 (UTC)

also, please explain the bolded sentence:

"According to Luca Codignola of the University of Genoa, contact with a powerful extraterrestrial civilization is comparable to occasions where one powerful civilization destroyed another, such as the arrival of Christopher Columbus and Hernán Cortés into the Americas and the subsequent destruction of the indigenous civilizations and their ways of life.[2] However, the applicability of such a model to contact with extraterrestrial civilizations, and that specific interpretation of the arrival of the European colonists to the Americas, have been disputed.[78] Even so, any large difference between the power of an extraterrestrial civilization and our own could be demoralizing and potentially cause or accelerate the collapse of human society.[39] Being discovered by a "superior" extraterrestrial civilization, and continued contact with it, might have psychological effects that could destroy a civilization, as is claimed to have happened in the past on Earth.[21]"

Reticuli88 (talk) 21:31, 16 August 2012 (UTC)

I've skimmed the cited article; the author mentions no claims of actual extraterrestrial contact. The author discusses contact between human civilizations and their often disastrous consequences. The sentence is just poorly worded. Clarityfiend (talk) 22:01, 16 August 2012 (UTC)

See also Cargo cult and European colonization of the Americas, which I have added to the article. μηδείς (talk) 22:29, 16 August 2012 (UTC)

I think a much better example for the article would be if the extraterrestrial's biochemistry was based on a solvent other than water. Imagine biting into an apple that was 90% ammonia. 203.27.72.5 (talk) 00:12, 17 August 2012 (UTC)

See Flast the Cryon in Attack of the Cybermen. μηδείς (talk) 00:57, 17 August 2012 (UTC)

The Way to Eden... Wnt (talk) 09:30, 17 August 2012 (UTC)

Advanced civilizations may well consist of self-replicating robots, and they could eat the entire Earth. Count Iblis (talk) 02:53, 17 August 2012 (UTC)

For that, see Greg Bear's The Forge of God and its sequel, Anvil of Stars. μηδείς (talk) 03:01, 17 August 2012 (UTC)

I don't know if pointing out where a theme was referenced in science fiction everytime someone brings one up is what we mean by "science reference desk" :P 203.27.72.5 (talk) 03:22, 17 August 2012 (UTC)

The earlier Berserker (Saberhagen) series was better, IMHO. Wnt (talk) 09:36, 17 August 2012 (UTC)

The idea of aliens using people for food or slaves seems rather absurd to me. Any technology that can move the extraterrestrials from one solar system to another in a reasonable time frame could also produce food in abundance and do all their work for them. The way alien contact could be negative, IMHO, is if they want the Earth, to colonize, and we get in their way, or if they see us as a potential future threat, so decide to exterminate us. StuRat (talk) 03:47, 17 August 2012 (UTC)

Surely, you don't mean that any interstellar travel technology is also necessarily a food sythnesis technique? 203.27.72.5 (talk) 04:45, 17 August 2012 (UTC)

No, I mean that any civilization with near-light-speed-travel can probably handle hydroponics, at the very least. Oh, and don't call me Shirley. :-) StuRat (talk) 05:12, 17 August 2012 (UTC)

I think that when we look at attempts to model 'pushy' aliens, like Childhood's End or The Day The Earth Stood Still, it is obvious that aliens capable of understanding Earth culture enough to take sides would absolutely be resented and their power would be seen as an enslavement. Of course, what is very difficult indeed for such novels to impart is the depth of knowledge in support of their positions, and the wisdom of the positions, that real aliens of a superior civilization might actually have. Nonetheless, it is quite plausible that aliens seeking to elevate human culture rather than oppress it would elect a tactic of inspiring certain individuals along the line of Jesus or Laozi to provide seminal ideas which, they would plan, would eventually bring about the desired ideological development with less disruption. Of course, then again, not making contact quickly also involves disruption, perhaps even lethal disruption for the planet (itself a common sci-fi motif...) Wnt (talk) 09:44, 17 August 2012 (UTC)

I've always been puzzled by 2001: A Space Odyssey, where the "helpful alien obelisk" apparent inspires chimps to murder each other, rather than, say, to work together for the common good. StuRat (talk) 15:58, 17 August 2012 (UTC)

Actually, given the history of colonialism and decolonization, I suppose it's not unrealistic. :( Wnt (talk) 23:43, 17 August 2012 (UTC)

SPOILER WARNING!!! It was intentional. The monoliths were neutral machines and thus didn't exactly influence the apes to kill each other. It was simply human/ape nature. This was underscored by the match cut of the jawbone thrown to the sky transforming into an orbitting satellite. The novel explains this in the finale, but the lack of narrative and the removal of the star child final scenes in the film makes it unclear. Those satellites are actually orbiting weapons platforms with nukes. A bigger stick. Explained even further in the later books of the series where when the monolith's controllers upon receiving the "evaluation" sent back by the Earth monoliths (unfortunately during World War II), decided to destroy humanity even though human society had outgrown that violent period by the time (~3000 AD) that response was received by the Solar System monoliths and the HAL-Bowman star child. -- OBSIDIAN†SOUL 00:42, 18 August 2012 (UTC)