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POPSResearchers turn one form of adult mouse cell directly into another Joan Brugge, Chair of the Department of Cell Biology at Harvard Medical School, said the new study "provides exciting new insights into yet another aspect of cell plasticity that was not appreciated previously and that offers great potential therapeutically. Direct reprogramming represents a more straight-forward strategy to treat diseases involving loss of function of specific cell populations than approaches requiring an intermediate embryonic stem cell," she said.
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POPSFuture for clean energy lies in 'big bang' of evolution For humans now there is the tantalising possibility of tweaking the photosynthetic reactions of cyanobacteria to produce fuels we want such as hydrogen, alcohols or even hydrocarbons, rather than carbohydrates. Progress at the research level has been rapid, boosting prospects of harnessing photosynthesis not just for energy but also for manufacturing valuable compounds for the chemical and biotechnology industries. Such research is running on two tracks, one aimed at genetically engineering real plants and cyanobacteria to yield the products we want, and the other to mimic their processes in artificial photosynthetic systems built with human-made components. Both approaches hold great promise and will be pursued in parallel, as was discussed at a recent workshop focusing on the photosynthetic reaction centres of cyanobacteria, organised by the European Science Foundation (ESF).
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POPSPioneering Research in Neuromorphic Electronics that Function Like the Biological Brain The HRL team's ultimate goal is to build a low-power, compact electronic chip combining a novel analog circuit design and a neuroscience-inspired architecture that can address a wide range of cognitive abilities--perception, planning, decision making, and motor control. In the initial two phases of the SyNAPSE program, the team will translate the neuronal and synaptic functions of the biological cortex into similar microelectronic functions.
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POPSThe Secret Of Fast Complex Brain Restructuring Up to now, it had been assumed that nerve cells can only exchange information via the synapses which are special contact points. However, synapses require up to two days to become fully functional - a waste of time and energy if the contact is to be broken down again. The brain could take almost 1000 years to develop if a synapse had to mature at each cell contact. It appears that nerve cells can also obtain information about their neighbours even without a synapse. Neurobiologists Christian Lohmann and Tobias Bonhoeffer from the Max Planck Institute for Neurobiology have now explained how they do that. The secret to how the information is exchanged: local calcium signals very quickly transmit all the necessary information to the cell. A synapse only actually develops when the cell and the contact point prove to be suitable candidates for long-term contact.
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POPSOn Law and Neuroscience An interesting read describing the influence of evolution theory and neuroscience on basic legal and moral concepts such as responsibility and free will.
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POPSExploding chromosomes fuel research about evolution of genetic storage
Dinoflagellates are stuffed at the core with tightly compacted chromosomes, yet these organisms contain neither histones nor nucleosomes. "What takes care of neutralizing DNA, to allow chromosomes to condense?" Levi-Setti asked. "Most biology books do not tell you." Other scientists had already identified positively charged atoms called cations as neutralizing factors. They found that dinoflagellate chromosomes explode upon the removal of calcium and magnesium cations. Levi-Setti has produced the first images of the distribution of these cations in dinoflagellate chromosomes. These images verify that cations, mainly of calcium and magnesium, neutralize DNA's enormous negative charge, and further suggest a critical role in folding the protein as well. The finding raises questions about the evolution of chromosomes, Rizzo said. "Did dinoflagellates once have histones and then lost them? Or did dinoflagellates never have histones and just 'figured out' a different way to fold lar
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POPSTransformers - The Nature of Alien Life The driving factor is a pragmatic desire to improve mental capacity. Alien beings may have already reached a point in their evolution where, having exhausted the potential of their biological brains, they have taken the next logical step and opted for robotic brains equipped with artificial intelligence. This brain swap may not be as far off for humans as one might think. In only a few decades, the computer revolution here on Earth has produced supercomputers capable of performing more than a quadrillion calculations per second. According to research by Hans Moravec, an artificial-intelligence expert at Carnegie Mellon University, that rate trumps the human brain’s estimated top speed of 100 trillion calculations per second. Some scientists speculate that in a few decades, an event called the technological singularity will occur, and machines armed with computer brains will become sentient and surpass human intelligence. Civilizations equipped with technology light-years ahead
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POPSCooking and Cognition: How Humans Got So Smart We started innovating. We tried different materials, such as bone, and invented many new tools, including needles for beadwork. Responding to, presumably, our first abstract thoughts, we started creating art and maybe even religion. To understand what caused the cognitive spurt, Khaitovich and colleagues examined chemical brain processes known to have changed in the past 200,000 years. Comparing apes and humans, they found the most robust differences were for processes involved in energy metabolism. The finding suggests that increased access to calories spurred our cognitive advances, said Khaitovich, carefully adding that definitive claims of causation are premature. The research is detailed in the August 2008 issue of Genome Biology.
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POPSSCIENTISTS SHOW HALLUCINOGEN CREATES UNIVERSAL “MYSTICAL” EXPERIENCE in the 1950s, showed signs of therapeutic potential or value in research into the nature of consciousness and sensory perception. “Human consciousness…is a function of the ebb and flow of neural impulses in various regions of the brain-the very substrate that drugs such as psilocybin act upon,” Schuster says. “Understanding what mediates these effects is clearly within the realm of neuroscience and deserves investigation.” “A vast gap exists between what we know of these drugs-mostly from descriptive anthropology-and what we believe we can understand using modern clinical pharmacology techniques,” says study leader Roland Griffiths, Ph.D., a professor with Hopkins’ departments of Neuroscience and Psychiatry and Behavioral Biology. “That gap is large because, as a reaction to the excesses of the 1960s, human research with hallucinogens has been basically frozen in time these last forty years.”
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POPSTHE ORIGIN OF BIOLOGICAL INFORMATION Yet Muller and Newman insist that population genetics, and thus evolutionary biology, has not identified a specifically causal explanation for the origin of true morphological novelty during the history of life. Central to their concern is what they see as the inadequacy of the variation of genetic traits as a source of new form and structure. They note, following Darwin himself, that the sources of new form and structure must precede the action of natural selection (2003:3)–that selection must act on what already exists. Yet, in their view, the “genocentricity” and “incrementalism” of the neo-Darwinian mechanism has meant that an adequate source of new form and structure has yet to be identified by theoretical biologists. Instead, Muller and Newman see the need to identify epigenetic sources of morphological innovation during the evolution of life. In the meantime, however, they insist neo-Darwinism lacks any “theory of the generative”
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POPSViruses can catch colds, says study that redefines life itself Prof La Scola and his colleagues were surprised to spot a smaller type of virus attached to the virus-making factory inside infected cells. The new virus - Sputnik - was unable to infect cells by itself but seemed to hijack the larger to achieve its infectious aims. By regulating the growth and death of plankton, giant viruses - and satellite viruses such as Sputnik - could be a major influence on ocean nutrient cycles and climate. "These viruses could be major players in global systems," Nature is told by Prof Curtis Suttle, an expert in marine viruses at the University of British Columbia in Vancouver.
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POPSMicropbes Under Sea Floor Shows Possibility of Alien Life However, this population lives at an unusual rate. Single-celled organisms usually consume food for energy and then rather than grow larger, simply divide and reproduce themselves. While the Bacteria Escherichia Coli, as an example, doubles its numbers every 20 minutes, these Archaea double on the order of hundreds or thousands of years and consume very little energy. "In essence, these microbes are almost, practically dead by our normal standards," says House. "They metabolize a little, but not much." According to House, organisms metabolizing at such slow rates is what we could expect to find in other areas of our solar system because such environments have much less energy available than on Earth. Perhaps, similar organisms may be in hydrothermal vents beneath the ice of Europa -- the second moon of Jupiter -- or in subsurface aquifers of Mars.
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POPSPrevailing theory of aging challenged in Stanford worm study To see whether these signal molecules were part of a wear-and-tear aging mechanism, the researchers exposed worms to stresses thought to cause aging, such as heat (a known stressor for nematode worms), free-radical oxidation, radiation and disease. But none of the stressors affected the genes that make the worms get old. So it looked as though worm aging wasn’t a storm of chemical damage. Instead, Kim said, key regulatory pathways optimized for youth have drifted off track in older animals. Natural selection can’t fix problems that arise late in the animals’ life spans, so the genetic pathways for aging become entrenched by mistake. Kim’s team refers to this slide as “developmental drift.”
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POPSDrug for Longer Life The other drug is a small synthetic chemical that is a thousand times as potent as resveratrol in activating sirtuin and can be given at a much smaller dose. Safety tests in people have just started, with no adverse effects so far. The hope is that activating sirtuins in people would, like a calorically restricted diet in mice, avert degenerative diseases of aging like diabetes, heart disease, cancer and Alzheimer’s. There is no Food and Drug Administration category for longevity drugs, so if the company is to submit a drug for approval, it needs to be for a specific disease. Nonetheless, longevity is what has motivated the researchers and what makes the drugs potentially so appealing.
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POPSArctic Scientists Explore a "Lost" 26-Million-Year-Old Ecosystem “The origin of life discussion comes up because the rocks that are exposed on this very slow spreading ridge are not volcanic, but instead come directly from Earth’s mantle,” says geochemist Susan Humphris. “The chemistry is very much like the volcanism that occurred on the primordial Earth. If you are thinking about origins of life, you’d like to have an area that is the closest analog to what was happening on the early Earth.”
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POPSResearchers Discover Remnant of an Ancient 'RNA World' Breaker's lab solved a decades-old mystery by describing how tiny circular RNA molecules called cyclic di-GMP are able to turn genes on and off. This process determines whether the bacterium swims or stays stationary, and whether it remains solitary or joins with other bacteria to form organic masses called biofilms. Bacterial use of RNA to trigger major changes without the involvement of proteins resolves one of the questions about the origin of life: If proteins are needed to carry out life's functions and DNA is needed to make proteins, how did DNA arise? The answer is what Breaker and other researchers call the RNA World. They believe that billions of years ago, single strands of nucleotides that comprise RNA were the first forms of life and carried out some of the complicated cellular functions now done by proteins. The riboswitches are highly conserved in bacteria, illustrating their importance and ancient ancestry, Breaker said.
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POPSNewly described 'dragon' protein could be key to bird flu cure This unexpected relationship between the two subunits could inspire a number of different therapies or vaccines for H5N1 that rely on muzzling the "dragon's" jaws with another molecule or chemical compound that would block the PB1 subunit's access to the PA site, according to Joachimiak. "If we can put a bit in the dragon's mouth, we can slow or even potentially someday stop the spread of avian flu," he said. "Since we are talking about a relatively small protein surface area, finding a way to inhibit RNA replication in H5N1 seems very feasible."
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POPSHow Your Brain Controls Time Warren Meck of Duke University argues that the brain measures long stretches of time by producing pulses. But the brain does not then count the pulses in the way a clock does. Instead, Meck suspects, it does something more elegant. It listens to the pulses as if they were music. At Humboldt University of Berlin in Germany, scientists have been building a model of how memory may store time. When neurons produce a regular cycle of signals, some signals come a little sooner and some come a little later. The researchers propose that as neurons pass these signals along, they can add tiny advances, some bigger than others. With these tiny wobbles, the brain can compress memories of time from several seconds down to hundredths of a second—a small enough package to store for later retrieval. As it stores time in memories, the brain may alter it in another way that is even more radical. It may record time so that our brains recall events in backward order. Scientists at MIT discovered re
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POPSNew Mode Of Gene Regulation Discovered In Mammals As research advances, the more it becomes clear, that gene regulation networks are actually complex computing machines. DNA is not a mere repository of information. What's more, the newly discovered mechanism is self referential, which adds another later of complexity to gene regulation processes.
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POPS'Mind's eye' influences visual perception The new findings offer an objective tool to assess the often-slippery concept of imagination. This is an interesting and fascinating experiment. It is perhaps a far shot but this may point towards the roots of human's ability and inclination to envision a future reality and than change the world around to fit this reality.
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POPSRight and wrong lessons from biology The opposite view stresses that evolution is an extremely effective way of searching parameter space, and that in consequence is that we should assume that biological design solutions are likely to be close to optimal for the environment for which they’ve evolved. Where these design solutions seem odd from our point of view, their unfamiliarity is to be ascribed to the different ways in which physics works at the nanoscale. At its most extreme, this view regards biological nanotechnology, not just as the existence proof for nanotechnology, but as an upper limit on its capabilities.
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POPSGene silencer and quantum dots reduce protein production to a whisper Each quantum dot was surrounded by a proton sponge that carried a positive charge. Without any quantum dots attached, the siRNA's negative charge would prevent it from penetrating a cell's wall. With the quantum-dot chaperone, the more weakly charged siRNA complex crosses the cellular wall, escapes from the endosome (a fatty bubble that surrounds incoming material) and accumulates in the cellular fluid, where it can do its work disrupting protein manufacture. Key to the newly published approach is that researchers can adjust the chemical makeup of the quantum dot's proton-sponge coating, allowing the scientists to precisely control how tightly the dots attach to the siRNA. Quantum dots were dramatically better than existing techniques at stopping gene activity. In experiments, a cell's production of a test protein dropped to 2 percent when siRNA was delivered with quantum dots. By contrast, the test protein was produced at 13 percent to 51 percent of normal levels when the siRNA
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POPSVirtual Unreality (Part 2) Looking from the perspective of a futuristic, perfect virtual reality, we are forced to question the very essence of our existence. What is the point of living if a utopia is provided for us? Once the superficial shell of reality is peeled from us, what is left of the human soul? What are the common denominators of our existence? The virtual world paradigm opens up our eyes to the limitations of reality, and shows us the true essence of what it means to be human.
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POPSZebra's Stripes, Butterfly's Wings: How Do Biological Patterns Emerge? Previous work identified a specific signal necessary for getting these fly egg cells to move; the problem is that this signal is “graded.” Like drops of ink spreading out on wet paper, this signal travels in between surrounding cells, gradually fading away as it moves outwards. But clear lines are required for pattern formation — there is no grey area between a zebra’s black and white stripes, between heart and liver cells and, in this case, between migrating cells and those that stay put. How are graded signals converted to a clear move or stay signal? By examining flies containing mutations in different genes, the researchers discovered that one gene in particular, called apontic, is important for converting a graded signal.
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POPSGenetically engineered cells make their own nanomagnets, providing clear MRI images. If genetically engineering cells to produce their own magnetic nanoparticles proves successful, this provides a new window through which to view many biological processes as they unfold, from the formation of tumors to the migration of stem cells injected to treat disease. "It's just amazing that they can get a mammalian cell to actually make the material," says Lee Josephson, an associate professor at the Harvard Medical School's Center for Molecular Imaging Research. "I think it's a really meaningful piece of work."
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