Applied Physics

Large swaths of garbled human DNA once dismissed as junk appear to contain some valuable sections, according to a new study by researchers at the Stanford University School of Medicine and the University of California-Santa Cruz. The scientists propose that this redeemed DNA plays a role in controlling when genes turn on and off. Gill Bejerano, PhD, assistant professor of developmental biology and of computer science at Stanford, found more than 10,000 nearly identical genetic snippets dotting the human chromosomes. Many of those snippets were located in gene-free chromosomal expanses once…

Ultra-hard materials are used for everything from drills that bore for oil and build new roads to scratch-resistant coatings for precision instruments and the face of your watch. UCLA scientists are now reporting a promising new approach to designing super-hard materials, which are very difficult to scratch or crack. UCLA scientists have made rhenium diboride, an “ultra-hard material.” Rhenium diboride is seen here in powder form (left), made from heating the elements in a furnace, and as a pellet made by a procedure called arc melting. Credit: UCLA Diamond is the hardest material known,…

Cilia, tiny hair-like structures that propel mucus out of airways, have to agree on the direction of the fluid flow to get things moving. Researchers at the Salk Institute for Biological Studies discovered a novel two-step mechanism that ensures that all cilia beat in unison. Their study, published in Nature, reveals that during early embryonic development, cilia point more or less in the general direction of the body's back end and start creating a weak flow. During the following refinement phase, all cilia get in line and trim their sails to the prevailing winds. Two ciliated cells…

Serotonin is a major signaling chemical in the brain, and it has long been thought to be involved in aggressive behavior in a wide variety of animals as well as in humans. Another brain chemical signal, neuropeptide Y (known as neuropeptide F in invertebrates), is also known to affect an array of behaviors in many species, including territoriality in mice. A new study by Drs. Herman Dierick and Ralph Greenspan of The Neurosciences Institute in San Diego shows that these two chemicals also regulate aggression in the fruit fly, Drosophila melanogaster. In a series of studies that used drug…

Scientists are questioning whether peer review, the internationally accepted form of scientific critique, is able to meet the challenges posed by the rapid changes in the research landscape. A report published by the European Science Foundation (ESF) has showcased a number of options that could lead to a greater openness to innovative research. The report "Peer review: its present and future states", which draws on ideas from an international conference in Prague in October 2006, reflects some concern on the shortcomings of peer review while outlines some possible measures to cope with…

University of Colorado at Boulder researchers are forecasting a one in three chance that the 2007 minimum extent of sea ice across the Arctic region will set an all-time record low. The researchers at CU-Boulder's Colorado Center for Astrodynamics Research also say there is a 57 percent chance the 2007 sea-ice minimum will be lower than the 2006 minimum of 2.27 million square miles, now the second lowest on record. There is a 70 percent chance the 2007 sea-ice minimum will rank within the lowest five years on record, according to Research Associate Sheldon Drobot of CCAR's Arctic Regional…

Raven, the mobile surgical robot developed by the University of Washington, is going into the Atlantic Ocean to participate in NASA's mission to submerge a surgeon and robotic gear in a simulated spaceship. For 12 days the surgical robotic system will be put through its paces in an underwater capsule that mimics conditions in a space shuttle. Surgeons back in Seattle will guide its movements. Raven, the mobile surgical robot developed in the UW's BioRobotics Lab, weighs about 50 pounds. Its nimble appendages can suture wounds and perform minimally invasive surgeries. Credit: David…

Ethanol is widely touted as an eco-friendly, clean-burning fuel. But if every vehicle in the United States ran on fuel made primarily from ethanol instead of pure gasoline, the number of respiratory-related deaths and hospitalizations would likely increase, according to a new study by Stanford University atmospheric scientist Mark Z. Jacobson. "Ethanol is being promoted as a clean and renewable fuel that will reduce global warming and air pollution,'' said Jacobson, associate professor of civil and environmental engineering. ''But our results show that a high blend of ethanol poses an equal…

Are you ready for "X-ray glasses" that see through fog - and even clothing? With their new world record in high-frequency submillimeter waves, researchers at the UCLA Henry Samueli School of Engineering and Applied Science are bringing that kind of imaging technology closer to reality. The record-setting 324-gigahertz frequency was accomplished using a voltage-controlled oscillator in a 90-nanometer complementary metal-oxide semiconductor (CMOS) integrated circuit, a technology used in chips such as microprocessors. The signal generator, which produces frequencies nearly 70 percent faster…

An earthquake engineer at Washington University in St. Louis has successfully performed the first test of wireless sensors in the simulated structural control of a model laboratory building. Shirley J. Dyke, Ph.D., the Edward C. Dicke Professor of Civil Engineering and director of the Washington University Structural Control and Earthquake Engineering Laboratory, combined the wireless sensors with special controls called magnetorheological dampers to limit damage from a simulated earthquake load. Her demonstration is the first step toward implementing wireless sensors for structural…