Domain: archives-ouvertes.fr
Stories and comments across the archive that link to archives-ouvertes.fr.
Comments · 10
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Re:But is it food.
Actually, our intestinal tract is that of a frugivore and shares no traits with mammals adapted to eating meat. The articles you linked are not scientific, and the Harvard article reads like a student paper in human evolution.
Evolutionary theory is the heart of what paleoanthropologists study, and there is no consensus among them about meat eating "making us human". Although some do make that claim, perpetuating the outdated logic of the "Man the Hunter/Man the Killer" theories of the '40s and '50s. Contrasting this, some modern scientists believe that the consumption of tubers was actually the energy source that led to increasing encephalization (brain enlargement) and gut reduction. Others argue it to be starches more broadly, and many effectively claim that any energy-dense food source would do the trick. The goal was simply reaching reproductive age after all, not avoiding cancer or reaching ripe old age in a healthy state.
The starch and tuber hypotheses used to get shot down because the earliest controlled use of fire didn't seem to emerge until relatively recently (200,000-400,000 years ago), and root starches require cooking in order to fulfill the kind of calorie counts that would have been necessary. With older and older dates emerging for human's control of fire (possibly as early as 1.7 million years ago), there is a growing belief that the development of cooking with heat in general was the key contributor to encephalization.
Anyone claiming that there is a scientific consensus on these matters simply isn't reading enough paleoanthropological literature. Every single dietary claim has been argued ferociously for decades. There are a few simple facts that no one seriously working in the field would argue however:
The human digestive system is that of a frugivore and has no specific biological gut adaptations that would be expected of a species that "evolved to eat meat". The same is true of our hominin ancestors. And based on dental calculus analysis and corprolite data, our ancestors ate shit-loads of plants. -
Re:But is it food.
We have no specific biological adaptations to eating meat. Our teeth are those of herbivores, and our digestive system is that of a frugivore. Based on dental calculus analysis and corprolite data, our ancestors ate shit-loads of plants.
But we do have at least one specific biological adaptation that is a result of eating meat. Our intestinal system and muscle mass as evolved to much smaller than equivalent animals that are pure herbivores.
http://time.com/4252373/meat-e...
http://news.harvard.edu/gazett...Some folks think that these adaptations allowed us the luxury of evolving larger brains...
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Re:But is it food.
We have no specific biological adaptations to eating meat. Our teeth are those of herbivores, and our digestive system is that of a frugivore. Based on dental calculus analysis and corprolite data, our ancestors ate shit-loads of plants.
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Re:Vote by mail.
Meh. I voted by mail a week ago. Got a paper ballot. Had lots of time to look up details on all the issues, including the judges, some obscure issues, and the people I'd never heard of.
Much better solution. No lines. No scheduling around work. Several weeks to study out everything.
I highly recommend it for everybody.
Any democratic election must respect the following principles. Let's see how vote by mail fares:
Unicity: The 'one voter, one vote' principle.
Fail: The ballot envelopes are easy to identify and thus to intercept and throw away while they are in the mail. for instance one can use statistical information to target envelopes posted from neighborhoods voting for the 'wrong' candidate.Confidentiality: Each voter expresses his/her choice alone.
Fail: The vote happens in an unsecured environment which leaves the voter open to coercicion, by family members, tenants, or employers.Anonymity: It is impossible to link a ballot to the voter who cast it.
Fail: The envelopes contains both your name and your ballot. Thus it is trivial for anyone in possession of your envelope to know and reveal who you voted for. Furthermore the envelopes are easily recognisable so it's not just election employees who can breach voting anonimity, it's any post office employee.Sincerity: The results of the election must faithfully reflect the will of the voters
Fail: Ballots can be tampered with while they are in storage waiting for election day.Transparency: Voters should be able to verify that the election system is working properly.
Fail: Ballots spend a lot of time outside the control of the voters and election overseers while they are in the mail. Once at the election offices they still spend days and nights outside of voter supervision. -
Re:Bioaccumulation Ahoy
http://hal.archives-ouvertes.f... three SE England estuaries all showing elevated heavy metal concentrations in sediment. Shellfish concentrate HMs for example lead and mercury, fish concentrate mercury in particular. Up the food chain, bioavailability increases. This is why fish farms regularly test for heavy metals and why you won't find any near industrial effluent outlets such as pretty much anywhere South of The Wash or East of Brighton.
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Re:Wait, *why* couldn't we do this?
You only need 1 gram of palladium to make a fuel cell that can deliver tens of kW ? That's impressive. Do you have a link to the technology?
Sure, first hit on Google, gets over 10KW/g of catalyst.
Keep in mind that weight doesn't matter for (solid) catalysts, but surface area does. If you can spread one gram over a square mile's worth of substrate, you get the same catalytic activity as if you used a kilogram with the same area. -
Practical problem solving needs math
If you examine modern papers on realistic graphics you'll see there are simple integrals that need to be solved, eg:
http://hal.archives-ouvertes.fr/inria-00288758
Bruneton, E, Neyret, F (2008), Precomputed Atmospheric Scattering, Computer Graphics -New York- Association for Computing Machinery- Forum 27, 4 (2008) 1079-1086By understanding more advanced mathematics you will have more advanced options for solving problems, eg. vector cross product for finding an axis to rotate about, or quaternions for a less intuitive way of doing the same, or differential equations for understanding the mechanics or aerodyamics of your game/ragdolls, statistics for understanding why the investment portfolio you are looking at is cleverly masking the reality of the situation. Or Linear Algebra for solving spatial and AI problems iteratively (the way a scientist would optimize, rather than the discrete way a computer scientist would first approach it). The more advanced mathematics you have the more tools you have at your disposal for solving any problem. Just because most people in today's society have a very tenuous grasp on how nature and artificial systems work dosn't mean that you ought to join them - (applied) mathematics is the tool that you use to gain understanding and solve real problems.
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Macroscopic wave–particle duality
Wave-particle duality has yet been observed with much bigger objects, on different physical basis but with astonishingly equivalent behaviour.
A 'walking' drop on a liquid surface behave like a particle with wave properties: diffraction, interference patterns, vibration quantization.
First, in a vibrating container they put a liquid like silicon oil, vibrations are just bellow the Faraday instability threshold. Then a drop of the same liquid is dropped on the surface, but it does not coalesce, it bounces. And further bounces make a static wave pattern on the liquid surface just bellow the drop and its immediate neighborhood. As the spike grows, instability increases and the drop slides down the spike, and start moving horizontally.
Then they have a combo object drop+wave pattern moving at 1/10th the speed of wave in this liquid, straight. They call it a walker.
What is really amazing is that the wave pattern below the drop has some kind of memory: it has accumulated energy from several drop bounces. It can also make the drop see "forward", as the small wave pattern bounces back from nearby obstacles. So the drop is "aware" of its environment and "recall" the path it has followed.
Diffraction is observed and explained by the multiple reflexions the wave makes when the drop passes through a small hole, randomizing the wave pattern and the angle of the path afterward. Interference patterns observed are explained a la de Broglie: as the drop passes through one of the two holes, its associated wave passes through both, carrying forward the message of the second hole to the drop and changing the statistical repartition of the drop's path direction. One more stunning result: they are circling the drop by moving the container (Coriolis), then the associated wave adopts a discrete series of pattern, depending on the speed and radius. Very much like the energy quantization of electrons.
English (and French) abstract
A short article (French but it has photos and formulas)
Full thesis (French,10Mb)" -
Macroscopic wave–particle duality
Wave-particle duality has yet been observed with much bigger objects, on different physical basis but with astonishingly equivalent behaviour.
A 'walking' drop on a liquid surface behave like a particle with wave properties: diffraction, interference patterns, vibration quantization.
First, in a vibrating container they put a liquid like silicon oil, vibrations are just bellow the Faraday instability threshold. Then a drop of the same liquid is dropped on the surface, but it does not coalesce, it bounces. And further bounces make a static wave pattern on the liquid surface just bellow the drop and its immediate neighborhood. As the spike grows, instability increases and the drop slides down the spike, and start moving horizontally.
Then they have a combo object drop+wave pattern moving at 1/10th the speed of wave in this liquid, straight. They call it a walker.
What is really amazing is that the wave pattern below the drop has some kind of memory: it has accumulated energy from several drop bounces. It can also make the drop see "forward", as the small wave pattern bounces back from nearby obstacles. So the drop is "aware" of its environment and "recall" the path it has followed.
Diffraction is observed and explained by the multiple reflexions the wave makes when the drop passes through a small hole, randomizing the wave pattern and the angle of the path afterward. Interference patterns observed are explained a la de Broglie: as the drop passes through one of the two holes, its associated wave passes through both, carrying forward the message of the second hole to the drop and changing the statistical repartition of the drop's path direction. One more stunning result: they are circling the drop by moving the container (Coriolis), then the associated wave adopts a discrete series of pattern, depending on the speed and radius. Very much like the energy quantization of electrons.
English (and French) abstract
A short article (French but it has photos and formulas)
Full thesis (French,10Mb)" -
price has little to do with reliability
"Nobody has yet mentioned the reason expensive journals persist in an era of cheap typesetting and distribution. It's because they provide two (inter-related) things to the science community: Quality control. For the good journals, when you submit an article it is typically reviewed (anonymously) by at least three of your peers, who make comments that are forwarded to you for response. You either argue your case against the reviewers or change your paper to accommodate."
Peer review has little to do with the price of the publications. Referees are not paid by the publisher of the journal (I know this because I've refereed a bunch of papers and never got anything more than a "thank you" note.)
There are enormous price differences between peer-reviewed journals. Some first-class journals in computer science, such as the Journal of the ACM, cost about 200 a year, while some other journals cost as much as 5000. The difference is that the former are published by nonprofits (scientific or technical societies) while the latter are published by for-profit entities, who charge universities through their nose.
A solution, yet unimplemented, would be to have editorial boards read and validate articles that are published on sites such as arXiv.org
Repeat: what's important is the editorial board, not the publisher.
(Shameless plug: the French research agency CNRS has a nice site for open publication: http://hal.archives-ouvertes.fr/index.php?langue=e n )