2/7/12 11:11 AM
[Science Daily] Standing in the way, however, is a major engineering hurdle: In processing, these delicate meshes must be heated or pressed to unite the crisscross pattern of nanowires that form the mesh, damaging them in the process. n a paper just published in the journal Nature , a team of engineers at Stanford has demonstrated a promising new nanowire welding technique that harnesses plasmonics to fuse the wires with a simple blast of light. Self-limiting At the heart of the technique is the physics of plasmonics, the interaction of light and metal in which the light flows across the surface of the metal in waves, like water on the beach. "When two nanowires lay crisscrossed, we know that light will generate plasmon waves at the place where the two nanowires meet, creating a hot spot. Brongersma is one of the study's senior authors. "The rest of the wires and, just as importantly, the underlying material are unaffected," noted Michael McGehee, a materials engineer and also senior author of the paper. "This ability to heat with precision greatly increases the control, speed and energy efficiency of nanoscale welding.
2/7/12 12:00 AM
[Science Daily]ScienceDaily (Feb. 3, 2012) - Mars may have been arid for more than 600 million years, making it too hostile for any life to survive on the planet's surface, according to researchers who have been carrying out the painstaking task of analysing individual particles of Martian soil. Phoenix touched down in the northern arctic region of the planet to search for signs that it was habitable and to analyse ice and soil on the surface. The results of the soil analysis at the Phoenix site suggest the surface of Mars has been arid for hundreds of millions of years, despite the presence of ice and the fact that previous research has shown that Mars may have had a warmer and wetter period in its earlier history more than three billion years ago. This implies that liquid water has been on the surface of Mars for far too short a time for life to maintain a foothold on the surface. We think the Mars we know today contrasts sharply with its earlier history, which had warmer and wetter periods and which may have been more suited to life. Future NASA and ESA missions that are planned for Mars will have to dig deeper to search for evidence of life, which may still be taking refuge underground.
2/7/12 11:11 AM
[Science Daily]"The patient experiences the inner voices as 100 per cent real, just as if someone was standing next to him and speaking" explains Professor Kenneth Hugdahl of the University of Bergen. "At the same time, he can't hear voices of others actually present in the same room." r Hugdahl's research group has made use of a variety of neuroimaging techniques, including functional magnetic resonance imaging technology (fMRI) to enable them quite literally to see what happens inside the brain when the inner voices make their presence known. So what happens when patients with schizophrenia hear a real voice and a hallucinatory one at the same time? "It would be natural to assume that neural activity would increase somewhat -- even twofold. It emerged that many researchers had observed either that a spontaneous activation of neurons occurs in patients hearing inner voices or that the patients' perception of actual voices becomes suppressed when these are heard simultaneously with inner voices. The neurons become 'preoccupied' and can't 'process' voices from the outside," explains Professor Hugdahl.
2/7/12 11:11 AM
[Science Daily]ScienceDaily (Feb. 6, 2012) - The future of disease diagnosis may lie in a "breathalyzer"-like technology currently under development at the University of Wisconsin-Madison. ew research published online in February in the peer-reviewed journal Metabolismdemonstrates a simple but sensitive method that can distinguish normal and disease-state glucose metabolism by a quick assay of blood or exhaled air. The new work shows that these biochemical changes can be detected much sooner than typical symptoms would appear -- even within a few hours -- offering hope of early disease detection and diagnosis. "With this methodology, we have advanced methods for tracing metabolic pathways that are perturbed in disease," says senior author Fariba Assadi-Porter, a UW-Madison biochemist and scientist at the Nuclear Magnetic Resonance Facility at Madison. "It's a cheaper, faster, and more sensitive method of diagnosis." he researchers studied mice with metabolic symptoms similar to those seen in women with polycystic ovary syndrome (PCOS), an endocrine disorder that can cause a wide range of symptoms including infertility, ovarian cysts, and metabolic dysfunction.
2/7/12 12:00 AM
[El Mundo] El laudo del TAS en el caso Contador invoca la responsabilidad objetiva, uno de los principios del Código Mundial Antidopaje, por la que todo deportista es responsable de lo que ingiere y, por tanto, de lo que aparezca en su organismo en un control. Ante el hecho ineludible de la aparición de clembuterol en el organismo del corredor, con independencia de la cantidad, y la imposibilidad de acreditar las hipótesis de su origen, ni por parte de la Agencia Mundial Antidopaje, ni por parte del ciclista, el TAS elabora una teoría de aproximación, al referirse a un "suplemento vitamínico contaminado". El TAS es una especie de Corte Suprema del deporte, creada a instancias del Comité Olímpico Internacional (CIO) durante la 'era Samaranch' e impulsada por el desaparecido vicepresidente Keba Mbaye, prestigioso jurista africano y miembro del Tribunal Internacional de Justicia. El organismo nació con la voluntad de ofrecer, vía arbitraje, un itinerario claro al laberinto del Derecho del deporte, donde se superponen ordenamientos jurídicos públicos y privados, los de los diferentes países en el uso de sus competencias y los estatutos y reglamentos de las federaciones, que son entidades de naturaleza jurídica privada, aunque en España tengan funciones públicas delegadas.
2/7/12 11:11 AM
[Science Daily]ScienceDaily (Feb. 6, 2012) - Boise State University biologists have uncovered why the chemical defenses in birch, a common type of tree found in North America, are toxic to snowshoe hares. Although it is well documented that the chemicals in birch are harmful to snowshoe hares and other herbivores, the mechanism for toxicity was not known until now. he study appears online in the Journal of Chemical Ecologyand is the first to specifically show how birch's toxicity affects snowshoe hares. "If we know diet selection and habitat use, it could lead to better management and conservation of both wildlife and the plants they eat," said study coauthor Jennifer Forbey, assistant professor of biological sciences. "This work represents a novel discovery and also helps explain the evolution and distribution of chemicals in trees and plants that was made possible by integrating expertise from ecology, pharmacology and chemistry.
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