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Possible fossilised bacteria in meteorites

ScienceDaily (May 4, 2011) - Using simple robots to simulate genetic evolution over hundreds of generations, Swiss scientists provide quantitative proof of kin selection and shed light on one of the most enduring puzzles in biology: Why do most social animals, including humans, go out of their way to help each other? In the online, open access journal PLoS Biology, EPFL robotics professor Dario Floreano teams up with University of Lausanne biologist Laurent Keller to weigh in on the oft-debated question of the evolution of altruism genes.

Our intrepid reporter performs an intimate act in an fMRI scanner to explore the pathways of pleasure and pain

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.

From the machinery of life to the fate of the cosmos, what can't science explain?

Those who are easily distracted from the task in hand may have "too much brain".

ScienceDaily (June 4, 2011) - Do the principles of quantum mechanics apply to biological systems? Until now, says Prof. Ron Naaman of the Institute's Chemical Physics Department (Faculty of Chemistry), both biologists and physicists have considered quantum systems and biological molecules to be like apples and oranges. But research he conducted together with scientists in Germany, which appeared recently in Science, shows that a biological molecule -- DNA -- can discern between quantum states known as spin.

A new strain of MRSA has been identified in cows' milk and in people, but don't stop drinking milk - the bug is killed off in pasteurisation. However, the strain evades detection by standard tests used by some hospitals to screen for MRSA (methicillin-resistant Staphylococcus aureus), potentially putting people at risk. Laura Garcia Alvarez, then at the University of Cambridge, and colleagues were studying infections in British cows when they discovered antibiotic-resistant bacteria that they thought were MRSA. However, tests failed to identify the samples as any known strains of the superbug. Sequencing the mystery bacteria's genomes revealed a previously unknown strain of MRSA with a different version of a gene called MecA. The new strain was also identified in samples of human MRSA, and is now known to account for about 1 per cent of human MRSA cases.

The lushest patches of some jungles are rooted in enigmatic black soil - with unexpected origins

A new study by MIT shows that babies can perform sophisticated analyses of how the physical world should behave. The scientists developed a computational model of infant cognition that accurately predicts infants' surprise at events that violate their conception of the physical world. The model, which simulates a type of intelligence known as pure reasoning, calculates the probability of a particular event, given what it knows about how objects behave. The close correlation between the model's predictions and the infants' actual responses to such events suggests that infants reason in a similar way, says Josh Tenenbaum, associate professor of cognitive science and computation at MIT.

It's not quite Cyclops, the sci-fi superhero from the X-Men franchise whose eyes produce destructive blasts of light, but for the first time a laser has been created using a biological cell. The human kidney cell that was used to make the laser survived the experience. In future such "living lasers" might be created inside live animals, which could potentially allow internal tissues to be imaged in unprecedented detail. It's not the first unconventional laser. Other attempts include lasers made of Jell-O and powered by nuclear reactors (see box below). But how do you go about giving a living cell this bizarre ability? Typically, a laser consists of two mirrors on either side of a gain medium - a material whose structural properties allow it to amplify light. A source of energy such as a flash tube or electrical discharge excites the atoms in the gain medium, releasing photons. Normally, these would shoot out in random directions, as in the broad beam of a flashlight, but a laser uses mirrors on either end of the gain medium to create a directed beam. As photons bounce back and forth between the mirrors, repeatedly passing through the gain medium, they stimulate other atoms to release photons of exactly the same wavelength, phase and direction. Eventually, a concentrated single-frequency beam of light erupts through one of the mirrors as laser light.

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.

ScienceDaily (July 28, 2011) - The human brain is the most complex of all organs, containing billions of neurons with their corresponding projections, all woven together in a highly complex, three-dimensional web. To date, mapping this vast network posed a practically insurmountable challenge to scientists. Now, however, a research team from the Heidelberg-based Max Planck Institute for Medical Research has developed a method for tackling the mammoth task. Using two new computer programs, KNOSSOS and RESCOP, a group of over 70 students mapped a network of more than 100 neurons -- and they did so faster and more accurately than with previous methods.

NBC exposes the "unspeakable" realities of the Japanese catastrophe in its 60 Minutes program Sunday night during which leading nuclear scientist Dr. Michio Kaku said radiation from Fukushima will impact of all of humanity.

ScienceDaily (Aug. 19, 2011) - A vast network of previously unmapped glaciers on the move from thousands of miles inland to the Antarctic coast has been charted for the first time by UC Irvine scientists. The findings will be critical to tracking future sea rise from climate change.

Life must have begun with a simple molecule that could reproduce itself - and now we think we know how to make one

Apply the electrodes... Externally modulating the brain's activity can boost its performance. The easiest way to manipulate the brain is through transcranial direct current stimulation (tDCS), which involves applying electrodes directly to the head to influence neuron activity with an electric current. Roi Cohen Kadosh's team at the University of Oxford showed last year that targeting tDCS at the brain's right parietal lobe can boost a person's arithmetic ability - the effects were still apparent six months after the tDCS session (newscientist.com/article/dn19679). More recently, Richard Chi and Allan Snyder at the University of Sydney, Australia, demonstrated that tDCS can improve a person's insight. The pair applied tDCS to volunteers' anterior frontal lobes - regions known to play a role in how we perceive the world - and found the participants were three times as likely as normal to complete a problem-solving task (newscientist.com/article/dn20080). Brain stimulation can also boost a person's learning abilities, according to Agnes Flöel's team at the University of Münster in Germany. Twenty minutes of tDCS to a part of the brain called the left perisylvian area was enough to speed up and improve language learning in a group of 19 volunteers (Journal of Cognitive Neuroscience, DOI: 10.1162/jocn.2008.20098). Using the same technique to stimulate the brain's motor cortex, meanwhile, can enhance a person's ability to learn a movement-based skill (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0805413106).

An international team of scientists has developed a novel X-ray technique for imaging atomic displacements in materials with unprecedented accuracy, using a recently discovered class of exotic materials - multiferroics - that can be simultaneously magnetically and electrically ordered. Multiferroics are also candidate materials for new classes of electronic devices. The researchers are from the European Synchrotron Radiation Facility (ESRF) in Grenoble (France), the University of Oxford, and the University College London.