Richardson said it's in the interest of our national space industry that commercial space could properly develop.
similar items
On working biochemists »
O'Leary: "Behe is a working biochemist"
Me: "Funny definition of working you're using there, Denyse"
Read the comments on this post...similar items Olfactory perceptual stability and discrimination. »
| Authors | DC Barnes, RD Hofacer, AR Zaman, RL Rennaker, DA Wilson |
|---|---|
| Journal | Nature neuroscience |
| Published | December 1, 2008 |
No two roses smell exactly alike, but our brain accurately bundles these variations into a single percept 'rose'. We found that ensembles of rat olfactory bulb neurons decorrelate complex mixtures that vary by as little as a single missing component, whereas olfactory (piriform) cortical neural ensembles perform pattern completion in response to an absent component, essentially filling in the missing information and allowing perceptual stability. This piriform cortical ensemble activity predicts olfactory perception.
similar items Tissue reconstruction in 3D-spheroids from rodent retina in a motion-free, bioreactor-based microstructure. »
| Authors | M Rieke, E Gottwald, KF Weibezahn, PG Layer |
|---|---|
| Journal | Lab on a chip |
| Published | December 1, 2008 |
While conventional rotation culture-based retinal spheroids are most useful to study basic processes of retinogenesis and tissue regeneration, they are less appropriate for an easy and inexpensive mass production of histotypic 3-dimensional tissue spheroids, which will be of utmost importance for future bioengineering, e.g. for replacement of animal experimentation. Here we compared conventionally reaggregated spheroids derived from dissociated retinal cells from neonatal gerbils (Meriones unguiculatus) with spheroids cultured on a novel microscaffold cell chip (called cf-chip) in a motion-free bioreactor. Reaggregation and developmental processes leading to tissue formation, e.g. proliferation, apoptosis and differentiation were observed during the first 10 days in vitro (div). Remarkably, in each cf-chip micro-chamber, only one spheroid developed. In both culture systems, sphere sizes and proliferation rates were almost identical. However, apoptosis was only comparably high up to 5 div, but then became negligible in the cf-chip, while it up-rose again in the conventional culture. In both systems, immunohistochemical characterisation revealed the presence of Müller glia cells, of ganglion, amacrine, bipolar and horizontal cells at a highly comparable arrangement. In both systems, photoreceptors were detected only in spheroids from P3 retinae. Benefits of the chip-based 3D cell culture were a reliable sphere production at enhanced viability, the feasibility of single sphere observation during cultivation time, a high reproducibility and easy control of culture conditions. Further development of this approach should allow high-throughput systems not only for retinal but also other types of histotypic spheroids, to become suitable for environmental monitoring and biomedical diagnostics.
similar items Punctuated Chirality. »
| Authors | M Gleiser, J Thorarinson, SI Walker |
|---|---|
| Journal | Origins of life and evolution of the biosphere : the journal of the International Society for the Study of the Origin of Life |
| Published | December 1, 2008 |
Most biomolecules occur in mirror, or chiral, images of each other. However, life is homochiral: proteins contain almost exclusively L-amino acids, while only D-sugars appear in RNA and DNA. The mechanism behind this fundamental asymmetry of life remains an open problem. Coupling the spatiotemporal evolution of a general autocatalytic polymerization reaction network to external environmental effects, we show through a detailed statistical analysis that high intensity and long duration events may drive achiral initial conditions towards chirality. We argue that life's homochirality resulted from sequential chiral symmetry breaking triggered by environmental events, thus extending the theory of punctuated equilibrium to the prebiotic realm. Applying our arguments to other potentially life-bearing planetary platforms, we predict that a statistically representative sampling will be racemic on average.
similar items Think Anatomy: The best resource online »
If you want to study anatomy or just find any kind of information, content, material focusing on anatomy, I make your search comfortable: check Think Anatomy. Lectures, podcasts, dissection videos, quizzes and many more. You can also submit your favourite choice.
Kudos to Vanessa Ruiz from Street Anatomy for creating this fantastic database.
MedHead: Interactive Learning »
We always argued playtime was more important than class time. So here is MedHead, an interactive card game designed for medical students. It’s a really good idea, but I would like to see something similar online as well.
MedHead is a creative way to master otherwise complex medical information. The game is designed for medical students, physician assistant students, or those in nurse practitioner programs.
Surprise your teacher and yourself as you learn the key terms and medical conditions in physical diagnosis.
TED: How science is nothing like democracy »
Recently, I was very pleased by the people's wise reactions to a February 2003 talk that TED posted to YouTube last week:
This talk by Lee Smolin is another postmodern tirade against the very essence of science. At 0:15, he tells us that he needed 25 seconds to agree with a project that could involve a USD 120 million gift. Well, that's not terribly shocking.
More seriously, at 1:25, we learn that everything we learned about science at school is wrong. Most importantly,
there is no scientific method.Wow. Hasn't Mr Smolin at least considered the possibility that the scientific method actually does exist - only he's been unable to take notice so far? He continues with bizarre comments about democratic communities and their strange links to science. Well, science has nothing to do with communities and certainly nothing with their collective ethics because science is about objective insights and evidence while ethics is always subjective.
At 3:14, he moves to "science of cosmology" and the "first science" was Aristotelian. So he explains some crystal and celestial spheres, being obviously unaware about the difference between this ancient crap on one side and science on the other side: this stuff is simply not "science" according to the present terminology because it hasn't survived any nontrivial empirical tests. Smolin even derives this "science" from some features of the ancient or medieval society where everything had a place (and institutions were hierarchical).
I have absolutely no idea what he could have possibly meant, except for emitting a sequence of meaningless sentences. In Newtonian physics or any kind of real science, things have their place, too. Modern cosmology also has hierarchies (clusters of stars, galaxies, and perhaps multiverse) - in fact, a more complex one than the old cosmology.
He completely omits the scientific revolution - because the scientific method, as pioneered by Galileo, obviously doesn't exist in Lee Smolin's picture of the world of knowledge. Instead, he talks about Isaac Newton but he says very different things than what scientists would normally say. More concretely, he claims that Newton invented a "liberal universe" because philosopher John Locke inspired him by some opinions about the society. The common theme is that there was no center.
According to Smolin, another pillar of Newton's world view was God, an external observer. That looks like a marijuana perspective on Newton's theory. To make things worse, he literally identifies Newton's theory with liberal political and legal theory around 5:50. Wow.
The 20th century revolution in physics is supposed to be about the pluralistic, "relational" society. He claims that there is nothing fixed or absolute in this Universe, zilch. I have no idea what he could possibly be talking about. Every scientific theory has fixed concepts and facts - e.g. the laws - and absolute, invariant quantities, and the modern theories often admit new absolute notions that didn't exist previously. For Smolin, God must be eliminated because no one can see everything in modern physics. Again, it makes no sense. He's just trying to project and impose his marijuana-induced political and ideological prejudices about politics on poor physics that has obviously nothing to do with this assorted crap.
General relativity and quantum mechanics are linked to "critical legal studies" at 7:20. He is probably talking about the Tribe-Obama paper on the curvature of constitutional space. ;-)
In his view, the "last" type of cosmology is "relational", meaning that objective facts can't exist in it. But there is nothing in cutting-edge science that would be linked to these words. At 7:50, he explains that guys can be men and women. Also, the Universe has made itself, he says. Suddenly, he returns to Darwin and promotes his (Smolin's) nonsense about the cosmic natural selection. He also claims that Darwin would make no sense in the Newtonian world (because it had "absolute quantities") - which is obviously rubbish, too. Darwin's theory was designed exactly in the context of the Newtonian world view on physics.
At 10:00, Smolin switches from the marijuana mode to cocaine. The two major 20th century scientific discoveries are Darwinism in biology (which was really a 19th century insight!) and democracy. The latter is thus necessarily "pluralistic" and "experimental". By now, all the buzzwords and adjectives are being mixed up arbitrarily.
The last minutes of the talk are dedicated to his "new revolution" in science which will reflect the postmodern philosophy and deconstructivism. There are many different agendas, no objective opinions, and this jelly will unify Darwinism and relationism, he thinks. ;-) Wow. This talk is almost indistinguishable from Alan Sokal's famous hoax paper about Hermeneutics of Quantum Gravity except that unlike Sokal, Smolin is as serious as the drugs allow him.
The reactions
What surprised me was that virtually all of those 100+ comments under the YouTube video realize that Smolin's talk was postmodern, anti-scientific crap that contradicts all the very basic features of science. Creationism is the most widely quoted example showing why democracy has nothing to do with scientific evidence.
I had to think why it was that almost everyone was wise and sane over there and why I had the bad luck to interact with so many people - in the physics blogosphere but also in the non-physics departments of the broader Academia (and sometimes even at physics departments, but fortunately not those where I have been) - who love to write similar deconstructivist junk about science as democracy etc. Well, the likely answer can be found after a few minutes of thinking and reading: most of the people who watched and commented on the video are subscribed to see the talks uploaded by TED.
These talks are typically very good and science-oriented and Smolin's talk just happened to be one of two recent lousy, anti-scientific tirades that TED has uploaded, leading some people to unsubscribe. Nevertheless, it looks surprising that a pretty informal group, TED, has collected a much more pro-scientific community than the institutionalized Academia. It is both surprising and worrisome.
The Academia is probably unable to cure itself - and in 2008, the postmodern charlatans could be able to crucify Alan Sokal if he did the same thing today - but at least Mike Lazaridis should be able to freeze the money to all of the deconstructivist babblers he's been feeding for years and hire a couple of selected TED subscribers instead.
similar items Dead link to the MRC OA mandate »
The UK Medical Research Council adopted an OA mandate in June 2006. At the time you could find it here. But four months later the link was dead and the policy moved here. Now the new link has died too and I can't find the policy's current location. If anyone can point me to it, I'd be grateful.
Meantime, here's the FAQ on the MRC OA mandate. The link to the FAQ works, but even the FAQ continues to use the dead link to the policy statement itself.
similar items Observatory Fingers Cosmic Ray 'Hot Spots' »
A Los Alamos National Laboratory cosmic-ray observatory has seen for the
first
time
two distinct hot spots that appear to be bombarding Earth with an excess of
cosmic rays. The research calls into question nearly a century of understanding
about galactic magnetic fields near our solar system.