BBC: A 53-year-old woman, paralyzed from the neck down because of spinocerebellar degeneration, may one day be able to perform simple tasks on her own thanks to advances in robotics. A study recently published in the Lancet medical journal describes how the subject had two microelectrodes implanted in the motor cortex of her brain. Tiny needles on each sensor detect electrical pulses from hundreds of individual brain cells. Those electrical pulses are then translated into commands to move the robotic arm. Over a period of weeks, the woman learned to use the arm to grab and move various objects. Eventually the researchers hope to mount the arm to the woman’s wheelchair so she can use it outside of a laboratory setting.
Daily Archives: December 17, 2012
New OLED achieves high efficiency without heavy metals
Ars Technica: Organic LEDs are thin, flexible materials that create light from electrically stimulated fluorescence. Electricity passing through an OLED excites both electrons and holes (their positive counterparts). When the electrons and holes meet, they form bound states called excitons that can be either singlet or triplet. The singlet excitons, which only form 25% of the time, release their bound energy as light; the triplets release their energy as heat. Adding heavy metal atoms to OLEDs yields almost 100% light emission, but heavy metals can be expensive. Hiroki Uoyama of Kyushu University in Japan and his colleagues have created a new OLED that maintains nearly the same level of light emission without the use of heavy metals. By carefully designing the OLED molecule, they were able to reduce the energy difference between singlet and triplet excitons so that the triplets converted into singlets and then released their energy as light. The engineered molecule still needs to be able to match the full abilities of heavy metal OLEDs before it will be useful in commercial devices.
Japan is the likely home of the next big particle collider
Nature: The International Linear Collider (ILC) is a proposed 31-km-long particle accelerator that will collide electrons and positrons. The primary goal will be to gain a clearer picture of the nature of the Higgs particle. CERN’s Large Hadron Collider uses proton collisions that create a massive amount of scattered particles. The ILC’s electron–positron collisions will result in much cleaner scattering. Japan, which lost its bid for ITER to France, is the leading candidate for hosting the facility. With extra funding available from its post-earthquake and tsunami reconstruction efforts and multiparty political support, Japan is making a concerted effort to win the project. Two sites on the island nation are being considered, both of which would have the collider built into the side of a mountain, not buried under flat ground as with other accelerators. However, with a projected cost between $7 billion and $8 billion, and with the US and Europe still recovering from economic downturns, the biggest roadblock to the project will be getting funding.
Prehistoric organisms may have been terrestrial
Science News: New findings regarding an early life form, Ediacaran fauna, which lived some 575 milllion to 542 million years ago, indicate that the creatures might have been land dwelling rather than ocean dwelling as had been previously thought. Based on recent analyses of rocks from Australia’s Ediacara Hills, Gregory Retallack of the University of Oregon in Eugene has determined that they were actually formed from fossilized soils and not from sea bottom as has long been believed. The study, which appears online in Nature, is controversial because not only would it redefine where Earth’s earliest complex multicellular organisms lived, but it also could mean that “decades of studies of ancient environments were based on flawed assumptions,” writes Susan Milius for Science News.