Biomolecular modeling: Scientists discover 'breakwater' to help control electron transfer
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 Researchers at the University of Calgary found that amino acid residues form a type of barrier to help in the process of electron transfer between proteins."This raises the bar for biomolecular modeling," says Dennis Salahub, U of C co-author of a paper published in the journal Proceedings of the National Academy of Sciences (PNAS). "At a fundamental level, it is by far the most detailed insight that has been obtained for the dynamic role of water in this kind of electron transfer, or for that matter any biochemical reaction."Electron transfer between proteins is the cornerstone of biological energy transfer. Every life-form uses this process to convert food or sunlight into chemical energy.The interdisciplinary team of researchers found that the electron travels over a bridge made of a water molecule, while residues on one of the proteins form a sort of 'molecular breakwater' to keep other water molecules away while the electron travels across the bridge."You don't want too many (water molecules around the bridge) because it gets too crowded and they're all bumping into each other and you can't get one to fit at just the right position and the right angle (for the bridge) for any length of time," says PhD student and co-author Nathan Babcock. "It's like being on a crowded subway where you can't get comfortable."In artificial mutations with a faulty breakwater, the water bridge is disrupted and the rate of electron transfer is markedly reduced, he says. »
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Scientists create nano-patterned superconducting thin films
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 A team of scientists from Bar-Ilan University, Israel, and the U.S. Department of Energy's (DOE) Brookhaven National Laboratory has fabricated thin films patterned with large arrays of nanowires and loops that are superconducting -- able to carry electric current with no resistance -- when cooled below about 30 kelvin (-243 degrees Celsius). Even more interesting, the scientists showed they could change the material's electrical resistance in an unexpected way by placing the material in an external magnetic field."Such superconducting nanowires and nano-loops might eventually be useful for new electronic devices -- that is the long-term vision," said Brookhaven Lab physicist Ivan Bozovic, who synthesized the superconducting films. "That is the long-term vision."He and his collaborators describe the research in Nature Nanotechnology, published online June 13, 2010.It has been a long-standing dream to fabricate superconducting nano-scale wires for faster, more powerful electronics. However, this has turned out to be very difficult if not impossible with conventional superconductors because the minimal size for the sample to be superconducting -- known as the coherence length -- is large. For example, in the case of niobium, the most widely used superconductor, it is about 40 nanometers. Very thin nano-wires made of such materials wouldn't act as superconductors.However, in layered copper-oxide superconductors, the coherence length is much smaller -- about one or two nanometers within the copper-oxide plane, and as small as a tenth of a nanometer out-of-plane. The fact that these materials operate at warmer temperatures, reducing the need for costly cooling, makes them even more attractive for real-world applications. »
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In deserts, which dunes are the most stable?
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 By modeling a desert where the wind blows in two directions, researchers from CNRS and Université Paris Diderot-Paris7 have succeeded in observing and highlighting, for the very first time, the formation process and long-term evolution of two types of very large sand dunes: transverse dunes and longitudinal dunes. They have demonstrated that longitudinal dunes and barchans -- croissant-shaped dunes formed in a unidirectional wind regime -- are the most stable over time. Their results should provide a better understanding of how dunes and deserts evolve on Earth and also help to deduce important information concerning wind regimes on Titan or Mars, for example.This work, carried out in collaboration with a PhD student from the Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique (CNRS / Observatoire de Paris / UPMC / Université Paris Diderot-Paris7), will be published in the June 2010 issue of the journal Geology.To study the formation and the stability of sand dunes, Stéphane Douady's team at the Laboratoire de Matière et Systèmes Complexes (CNRS / Université Paris Diderot-Paris7) has designed an ingenious device that reproduces, in miniature scale in the laboratory, the much larger dunes found in deserts. Their experimental model is made of glass beads set in motion by water in the same way as grains of sand are moved by winds. The advantages are that the resulting dunes formed of glass beads are small (a few centimeters) and build up rapidly under water. The resulting shapes are similar to wind-generated dunes, which has enabled researchers to study in detail the mechanisms involved in their formation. »
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NASA demonstrates tsunami prediction system
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 A NASA-led research team has successfully demonstrated for the first time elements of a prototype tsunami prediction system that quickly and accurately assesses large earthquakes and estimates the size of resulting tsunamis.After the magnitude 8.8 Chilean earthquake on Feb. 27, a team led by Y. Tony Song of NASA's Jet Propulsion Laboratory in Pasadena, Calif., used real-time data from the agency's Global Differential GPS (GDGPS) network to successfully predict the size of the resulting tsunami. The network, managed by JPL, combines global and regional real-time data from hundreds of GPS sites and estimates their positions every second. It can detect ground motions as small as a few centimeters."This successful test demonstrates that coastal GPS systems can effectively be used to predict the size of tsunamis," said Song. "This could allow responsible agencies to issue better warnings that can save lives and reduce false alarms that can unnecessarily disturb the lives of coastal residents."Song's team concluded that the Chilean earthquake, the fifth largest ever recorded by instruments, would generate a moderate, or local, tsunami unlikely to cause significant destruction in the Pacific. The tsunami's effect was relatively small outside of Chile. »
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Small Businesses: Better policy support for EU's job engine
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 With the onset of the economic crisis in 2008, a very positive development of small and medium enterprises (SME) has come to a halt. Between 2002 and 2008, SMEs in the EU turned out to be the most important European Economy job engine. With 9.4 million jobs created between 2002 and 2008 SMEs outperformed large firms. This is in sharp contrast to an estimated loss of 3.25 million jobs in the SME sector over 2009 and 2010 further to the annual SME report published today. For each EU Member State and 10 more countries, selected key facts describing the national SME sector are provided, such as number of SMEs and employment creation. They also underline that Member States have undertaken many relevant policy actions, but much more needs to be done to ensure that the guidelines set by the Small Business Act (SBA) are fully implemented.European Commission Vice-President Antonio Tajani, in charge of Industry and Entrepreneurship, said: "SMEs represent our economy's future, only they can generate new employment opportunities.. In light of the rather testing times ahead, an effective policy response is crucial in helping SMEs to be successful. Member States should step up actions that give a boost to SMEs. For SMEs to thrive, they need a more business-friendly environment across Europe".Providing jobs for almost 90 million Europeans, Europe’s 20.7 million SMEs continue to be the EU's economic backbone. To spur its role as the EU’s most important job generator, a speedy implementation of the actions contained in the Small Business Act (SBA) is critical. It is the EU’s flagship SME policy initiative and foresees actions by the Commission as well as by Member States in 10 different policy areas (see graph below).The main conclusions of the SME performance review are: SMEs outperformed large firms in 2002-2008 in employment generation: On average, between 2002 and 2008, the number of jobs in SMEs increased by 1.9% annually, while the number of jobs in large enterprises increased by only 0.8% annually.Crisis struck large and medium firms first, but smallest ones hit harder now: Estimates for EU-27 SMEs' production in EU-27 in 2009 hint at a decline by 5.5%. In 2009, this happened mostly in large and medium-sized enterprises, and less so for micro and small enterprises which are expected to be most affected in 2010 and beyond as initial support measures are phased out.SMEs in United States hit hard too: The number of businesses is estimated to have declined by 0.6% in 2008 and by 2.2% in 2009.Member States active in implementing SME support measures: As regards policy developments, the SBA fact sheets reveal that more than 500 policy measures across all ten SBA principles were implemented in 2007-2009. Only a minority 9 of Member States were active across the entire range of the 10 SBA principles. »
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Single-molecule devices can serve as powerful new science tools
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 With controlled stretching of molecules, Cornell researchers have demonstrated that single-molecule devices can serve as powerful new tools for fundamental science experiments. Their work has resulted in detailed tests of long-existing theories on how electrons interact at the nanoscale.The work, led by professor of physics Dan Ralph, is published in the June 10 online edition of the journal Science. First author is J.J. Parks, a former graduate student in Ralph's lab.The scientists studied particular cobalt-based molecules with so-called intrinsic spin -- a quantized amount of angular momentum.Theories first postulated in the 1980s predicted that molecular spin would alter the interaction between electrons in the molecule and conduction electrons surrounding it, and that this interaction would determine how easily electrons flow through the molecule. Before now, these theories had not been tested in detail because of the difficulties involved in making devices with controlled spins.Understanding single-molecule electronics requires expertise in both chemistry and physics, and Cornell's team has specialists in both."People know about high-spin molecules, but no one has been able to bring together the chemistry and physics to make controlled contact with these high-spin molecules," Ralph said.The researchers made their observations by stretching individual spin-containing molecules between two electrodes and analyzing their electrical properties. They watched electrons flow through the cobalt complex, cooled to extremely low temperatures, while slowly pulling on the ends to stretch it. At a particular point, it became more difficult to pass current through the molecule. The researchers had subtly changed the magnetic properties of the molecule by making it less symmetric. »
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Physicists reveal how to cope with 'frustration': Quantum simulation can be scaled to large systems
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 For most people, frustration is a condition to be avoided. But for scientists studying certain "frustrated" ensembles of interacting components -- that is, those which cannot settle into a state that minimizes each interaction -- it may be the key to understanding a host of puzzling phenomena that affect systems from neural networks and social structures to protein folding and magnetism. Frustration has typically been extremely difficult to study because even systems with relatively few components have interactions so complex that they cannot be modeled effectively on the best conventional electronic computers. Now, however, a team of researchers has simulated frustration in the smallest possible quantum system in a precisely controllable experimental arrangement, one which can be extended to much larger systems. In addition, they have demonstrated for the first time how frustration is related to a bizarre but highly useful quantum-mechanical condition called "entanglement." »
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Using nature's design principles to create specialized nanofabrics
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 In nature, cells and tissues assemble and organize themselves within a matrix of protein fibers that ultimately determines their structure and function, such as the elasticity of skin and the contractility of heart tissue. These natural design principles have now been successfully replicated in the lab by bioengineers at the Wyss Institute for Biologically Inspired Engineering and the School of Engineering and Applied Sciences (SEAS) at Harvard University.In nature, cells and tissues assemble and organize themselves within a matrix of protein fibers that ultimately determines their structure and function, such as the elasticity of skin and the contractility of heart tissue. These natural design principles have now been successfully replicated in the lab by bioengineers at the Wyss Institute for Biologically Inspired Engineering and the School of Engineering and Applied Sciences (SEAS) at Harvard University. »
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First Images of Heavy Electrons in Action: Characteristics of 'Hidden Order' in Unusual Uranium Compound
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 Using a microscope designed to image the arrangement and interactions of electrons in crystals, scientists have captured the first images of electrons that appear to take on extraordinary mass under certain extreme conditions.The technique reveals the origin of an unusual electronic phase transition in one particular material, and opens the door to further explorations of the properties and functions of so-called heavy fermions. Scientists from the U.S. Department of Energy's (DOE) Brookhaven National Laboratory, McMaster University, and Los Alamos National Laboratory describe the results in the June 3, 2010, issue of Nature."Physicists have been interested in the 'problem' of heavy fermions -- why these electrons act as if they are hundreds or thousands of times more massive under certain conditions -- for thirty or forty years," said study leader Séamus Davis, a physicist at Brookhaven and the J.D. White Distinguished Professor of Physical Sciences at Cornell University. Understanding heavy fermion behavior could lead to the design of new materials for high-temperature superconductors. Superconductivity allows materials to carry current with no energy loss.In the current study, the scientists were imaging electronic properties in a material composed of uranium, ruthenium, and silicon that itself has been the subject of a 25-year scientific mystery. In this material -- synthesized by Graeme Luke's group at McMaster -- the effects of heavy fermions begin to appear as the material is cooled below 55 kelvin (-218 °C). Then, an even more unusual electronic phase transition occurs below 17.5K. »
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Putting youth back into science
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 We all know that young people love gadgets and technology, so why is it that fewer young men and women are choosing science subjects and pursuing scientific careers? The aim of the YOSCIWEB ('Young people and the images of science on websites') project was to understand what makes science appealing to young people and what internet tools can be used to make science more attractive. The project was funded EUR 489,122 under the Science in Society (SIS) Programme of the EU's Seventh Framework Programme (FP7). Society relies on science and technology (S&T) to generate solutions to the many challenges we are presented with today and will face in the future. If the drop in interest among young people (particularly young women) in S&T subjects continues, then the trend is likely to have significant consequences for Europe. To stop and even reverse this pattern, the European Union supports a range of initiatives that pursue greater participation by young people in science and encourage long-term scientific careers. As one of these projects, the focus for the YOSCIWEB team was on science's image; the partners specifically looked at different ways of correcting the perceptions of science as being out of reach, dull and unfashionable. Since young people use digital mediums to communicate and access information, the researchers decided to examine the best ways (e.g. tools and methods to use and how) to communicate science through the Internet. This information would then form the basis of best practice guidelines and recommendations for stakeholders, especially creators of popular scientific websites. The benefits would ultimately have a cascading effect on the adult population at large, who also struggle to penetrate the scientific world in ways that are meaningful to them. The project was a 27-month collaboration between 7 partners from Bulgaria, Estonia, France, Iceland, the Netherlands, Spain and the UK. As well as assessing the current situation in general terms, the team conducted a deeper analysis of a the 7 partner countries. »
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