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As someone who's researched dark matter extensively, it is my determination that dark matter most likely exists, although explaining exactly what it is is a challenge. Over this next series, I would like to lead you through the evidence, observations and discoveries that have led me to this conclusion, and I hope that I explain this well enough that it leads you to draw the same ones for yourself.

In a recent study, researchers show that a gene called DMRT1 found only on the Z chromosome partly explains bird "maleness". When a ZZ embryo gets less DMRT1, the embryos start to take on some female traits. These studies show us that bird gender can be partly explained by genetics. Not having enough of a single gene can keep a bird from becoming a bona fide male bird. But this doesn't rule out the possibility of a female gene being on the W chromosome. Scientists just haven't yet found one.

An asteroid strike may not only account for the demise of ocean and land life 65 million years ago, but the fireball's path and the resulting dust, darkness and toxic metal contamination may explain the geographic unevenness of extinctions and recovery, according to Penn State geoscientists.

COULD the structure of space and time be sketched out inside a cousin of plain old pencil lead? The atomic grid of graphene may mimic a lattice underlying reality, two physicists have claimed, an idea that could explain the curious spin of the electron. Graphene is an atom-thick layer of carbon in a hexagonal formation. Depending on its position in this grid, an electron can adopt either of two quantum states - a property called pseudospin which is mathematically akin to the intrinsic spin of an electron. Most physicists do not think it is true spin, but Chris Regan at the University of California, Los Angeles, disagrees. He cites work with carbon nanotubes (rolled up sheets of graphene) in the late 1990s, in which electrons were found to be reluctant to bounce back off these obstacles. Regan and his colleague Matthew Mecklenburg say this can be explained if a tricky change in spin is required to reverse direction. Their quantum model of graphene backs that up. The spin arises from the way electrons hop between atoms in graphene's lattice, says Regan. So how about the electron's intrinsic spin? It cannot be a rotation in the ordinary sense, as electrons are point particles with no radius and no innards. Instead, like pseudospin, it might come from a lattice pattern in space-time itself, says Regan. This echoes some attempts to unify quantum mechanics with gravity in which space-time is built out of tiny pieces or fundamental networks (Physical Review Letters, vol 106, p 116803). Sergei Sharapov of the National Academy of Sciences of Ukraine in Kiev says that the work provides an interesting angle on how electrons and other particles acquire spin, but he is doubtful how far the analogy can be pushed. Regan admits that moving from the flatland world of graphene to higher-dimensional space is tricky. "It will be interesting to see if there are other lattices that give emergent spin," he says.

Complete video at: http://fora.tv/2009/05/23/Marcus_Chown_in_Conversation_with_Fred_Watson Marcus Chown, author of Quantum Theory Cannot Hurt You: A Guide to the Universe, discusses the mechanics behind quantum computers, explaining that they function by having atoms exist in multiple places at once. He predicts that quantum computers will be produced within 20 years. ----- The two towering achievements of modern physics are quantum theory and Einsteins general theory of relativity. Together, they explain virtually everything about the world in which we live. But almost a century after their advent, most people havent the slightest clue what either is about. Radio astronomer, award-winning writer and broadcaster Marcus Chown talks to fellow stargazer Fred Watson about his book Quantum Theory Cannot Hurt You. - Australian Broadcasting Corporation Marcus Chown is an award-winning writer and broadcaster. Formerly a radio astronomer at the California Institute of Technology, he is now cosmology consultant of the weekly science magazine New Scientist. The Magic Furnace, Marcus' second book, was chosen in Japan as one of the Books of the Year by Asahi Shimbun. In the UK, the Daily Mail called it "a dizzy page-turner with all the narrative devices you'd expect to find in Harry Potter". His latest book is called Quantum Theory Cannot Hurt You.

David Baum, University of Wisconsin, says: "All agree that eukaryotes arose from a symbiotic relationship between two cell types: bacteria that became mitochondria and a host cell, archaea, or a close relative of archaea, that became the cytoplasm and nucleus. This symbiosis explains the origin of mitochondria, but what about other eukaryotic structures, most notably the nucleus?" The Baums' inside-out theory provides a gradual path by which eukaryotic cells could have evolved. The first stage began with a bacterial cell whose outer membrane forms protrusions, which the Baums call 'blebs', that reached out from the cell. These protrusions trapped free-living mitochondria-like bacteria between them. Using the energy gained from being in close contact with bacteria (and using bacterial-derived lipids), cells were able to get bigger and expand the size of their blebs. The sides of the blebs formed the endoplasmic reticulum and their inner surfaces formed the outer membrane of the nucleus, with the original outer membrane of the archaeon becoming what we now call the inner nuclear membrane. Finally, the fusion of blebs with one another led to the formation of the plasma membrane. The result was the eukaryotic cell as we now know it. This inside-out theory is explained in more detail using a diagram in the research article (see notes to editors).

MindModeling@Home (Beta) is a research project that uses volunteer computing for the advancement of cognitive science. The research focuses on utilizing computational cognitive process modeling to better understand the human mind. We need your help to improve on the scientific foundations that explain the mechanisms and processes that enable and moderate human performance and learning.

"Lauren Brent: The discovery of friendship in animals Primatologist and evolutionary biologist Lauren Brent has spent over 6 years researching monkeys in the hopes of explaining how social behaviors evolved in our closest living relative"

"Synthetic Biology promises low-cost, exponentially scalable products and global health solutions in the form of self-replicating organisms, or "living devices." As these promises are realized, proof-of-concept systems will gradually migrate from tightly regulated laboratory or industrial environments into private spaces as, for instance, probiotic health products, food, and even do-it-yourself bioengineered systems. What additional steps, if any, should be taken before releasing engineered self-replicating organisms into a broader user space? In this review, we explain how studies of genetically modified organisms lay groundwork for the future landscape of biosafety."

"Explore simultaneously in space and time with Time Machine Each Time Machine on this page captures a process in extreme detail over space and time, with billions of pixels of explorable resolution. Choose a time machine and zoom into the image while traveling backwards or forwards through time. Select a Time Warp and the time machine's authors will take you on a guided space-time tour with text annotations explaining what you are viewing. You can even learn how to create your own Time Machines and Warps."

"When the right microorganisms are at work, immune cells involved in the development of autoimmune illnesses like psoriasis, multiple sclerosis and arthritis, can develop anti-inflammatory properties. Scientists at Charité - Universitätsmedizin Berlin and the Institute for Research in Biomedicine, Bellinzona, Switzerland, have now made this discovery. Their work is published in the current issue of the scientific journal Nature*. The scientists were able to prove that particular fungi activate the immune cells involved in the development of certain illnesses, whereas other microorganisms, in particular bacteria that are found naturally on our skin, lend an anti-inflammatory function to them. "This not only demonstrates that the composition of our microflora has a decisive role in the development of chronic illnesses, but also that the key cells causing illness can develop an anti-inflammatory 'twin'," explained Dr. Christina Zielinski, first author of the study."

KSL conducts research in the areas of knowledge representation and automated reasoning in the Artificial Intelligence Laboratory of the Department of Computer Science at Stanford University. Current work focuses on enabling technology for the Semantic Web, hybrid reasoning, explaining answers from heterogeneous applications, deductive question-answering, representing and reasoning with multiple contexts, knowledge aggregation, ontology engineering, and knowledge-based technology for intelligence analysts and other knowledge workers.

"explains how nitric oxide, a signaling molecule involved in the immune system, leads to biofilm formation. "It is estimated that about 80 percent of human pathogens form biofilms during some part of their life cycle," said Scripps Research president and CEO Michael Marletta, PhD, who led the work."

The book is about networked science: the use of online tools to transform the way science is done. In the book I make the case that networked science has the potential to dramatically speed up the rate of scientific discovery, not just in one field, but across all of science. Furthermore, it won't just speed up discovery, but will actually amplify our collective intelligence, expanding the range of scientific problems which can be attacked at all. But, as I explain in the book, there are cultural obstacles that are blocking networked science from achieving its full potential. And so the book is also a manifesto, arguing that networked science must be open science if it is to realize its potential. Making the change to open science is a big challenge. In my opinion it's one of the biggest challenges our society faces, one that requires action on many fronts. One of those fronts is to make sure that everyone - including scientists, but also grant agencies, governments, libraries, and, especially, the general public -- understands how important the stakes are, and how urgent is the need for change.

"In our recent paper, we take a different approach. We consider how measurements work in the macroworld, finding that some quantum features are simply unobservable. Most remarkably, this approach shows that something called quantum nonlocality disappears for objects big enough to contain roughly the Avogadro number of atoms-the number of atoms you'd expect in a few grams of matter."

"Our Juliets (as parents longing for grandchildren will recognize with a sigh) may experience the tumult of love for 20 years before they settle down into motherhood. And our Romeos may be poetic lunatics under the influence of Queen Mab until they are well into graduate school. What happens when children reach puberty earlier and adulthood later? The answer is: a good deal of teenage weirdness. Fortunately, developmental psychologists and neuroscientists are starting to explain the foundations of that weirdness. Photos: The Trials of Teenagers View Slideshow [SB10001424052970204573704577187080963983566] Everett Collection James Dean in the 1955 film 'Rebel Without A Cause' The crucial new idea is that there are two different neural and psychological systems that interact to turn children into adults"

"Our results indicate that communities where species are evenly and distantly related to one another are more stable compared to communities where phylogenetic relationships are more clumped. This result could be explained by a phylogenetic sampling effect, where some lineages show greater stability in productivity compared to other lineages, and greater evolutionary distances reduce the chance of sampling only unstable groups. However, we failed to find evidence for similar stabilities among closely related species. Alternatively, we found evidence that plot biomass variance declined with increasing phylogenetic distances, and greater evolutionary distances may represent species that are ecologically different (phylogenetic complementarity). Accounting for evolutionary relationships can reveal how diversity in form and function may affect stability."

"New research from Case Western Reserve University and University of Toronto neuroscientists finds that the brains of autistic children generate more information at rest - a 42% increase on average. The study offers a scientific explanation for the most typical characteristic of autism - withdrawal into one's own inner world. The excess production of information may explain a child's detachment from their environment. "

Dr Simon Archer and his team at Surrey University were particularly interested in looking at the genes that were switched on or off in our volunteers by changes in the amount that we had made them sleep. "We found that overall there were around 500 genes that were affected," Archer explained. "Some which were going up, and some which were going down." What they discovered is that when the volunteers cut back from seven-and-a-half to six-and-a-half hours' sleep a night, genes that are associated with processes like inflammation, immune response and response to stress became more active. The team also saw increases in the activity of genes associated with diabetes and risk of cancer. The reverse happened when the volunteers added an hour of sleep. So the clear message from this experiment was that if you are getting less than seven hours' sleep a night and can alter your sleep habits, even just a little bit, it could make you healthier