WASHINGTON D.C. Feb. 25, 2014 -- A Chinese-U.S. research team is exploring the use of metamaterials -- artificial materials engineered to have exotic properties not found in nature -- to create devices that manipulate sound in versatile and unprecedented ways.
In the journal Applied Physics Letters, the team reports a simple design for a device, called an acoustic field rotator, which can twist wavefronts inside it so that they appear to be propagating from another direction.
Choosing the right physical technique to analyse paintings can make all the difference when it comes to ascertaining their authenticity. Now, a painting initially attributed as belonging to a series called 'Contraste de formes' by French Cubist painter Fernand Léger has definitely been identified as a forgery. This is the first time it has been possible to identify a fake painting by relying on the anomalous behaviour of the concentration of the radioactive form of carbon (14C) in the atmosphere after 1955 to date the canvas.
MILWAUKEE – After having recently discovered a new way to propagate multiple beams of light through a single strand of optical fiber, engineers at the University of Wisconsin-Milwaukee (UWM) now have found that their novel fiber architecture can transmit images with a quality that is comparable or better than the current commercial endoscopy imaging fibers.
Because of this, the work has potential not only in next-generation high-speed communication, but also biomedical imaging.
Researchers have devised a way of making tiny holes of controllable size in sheets of graphene, a development that could lead to ultrathin filters for improved desalination or water purification.
The team of researchers at MIT, Oak Ridge National Laboratory, and in Saudi Arabia succeeded in creating subnanoscale pores in a sheet of the one-atom-thick material, which is one of the strongest materials known. Their findings are published in the journal Nano Letters.
ATLANTA--Protected natural areas in Costa Rica reduced poverty by 16 percent in neighboring communities, mainly by encouraging ecotourism, according to new research published today in the Proceedings of the National Academy of Sciences.
Although earlier studies indicated that establishing protected areas in poor regions can lead to reductions in poverty, there was no clear understanding why or how it happens.
HONOLULU – Scientists are revealing how microbes living on floating pieces of plastic marine debris affect the ocean ecosystem, and the potential harm they pose to invertebrates, humans and other animals. New research being presented here today delves deeper into the largely unexplored world of the "Plastisphere" – an ecological community of microbial organisms living on ocean plastic that was first discovered last year.
New research results suggest that magma sitting 4-5 kilometers beneath the surface of Oregon's Mount Hood has been stored in near-solid conditions for thousands of years.
The time it takes to liquefy and potentially erupt, however, is surprisingly short--perhaps as little as a couple of months.
The key to an eruption, geoscientists say, is to elevate the temperature of the rock to more than 750 degrees Celsius, which can happen when hot magma from deep within the Earth's crust rises to the surface.
Scientists on the CDF and DZero experiments at the U.S. Department of Energy's Fermi National Accelerator Laboratory have announced that they have found the final predicted way of creating a top quark, completing a picture of this particle nearly 20 years in the making.
LIVERMORE, Calif. -- Volcanic eruptions in the early part of the 21st century have cooled the planet, according to a study led by Lawrence Livermore National Laboratory. This cooling partly offset the warming produced by greenhouse gases.
"Mottronics" is a term seemingly destined to become familiar to aficionados of electronic gadgets. Named for the Nobel laureate Nevill Francis Mott, Mottronics involve materials – mostly metal oxides - that can be induced to transition between electrically conductive and insulating phases. If these phase transitions can be controlled, Mott materials hold great promise for future transistors and memories that feature higher energy efficiencies and faster switching speeds than today's devices.
Alexandria, VA – On a beautiful, clear June morning in 1954, a massive wave suddenly swept out of Lake Michigan killing at least seven people along the Chicago waterfront. At the time, the wave was attributed to a storm that had earlier passed over northern Lake Michigan, but how it came to swamp faraway Chicago, with no warning, was not understood.
The Great Lakes, along with the Mediterranean, Japan and many other parts of the world, have a long history of such waves, which have characteristics similar to tsunamis triggered by earthquakes or landslides.
Recovering from natural disasters usually means rebuilding infrastructure and reassembling human lives. Yet ecologically sensitive areas need to heal, too, and scientists are pioneering new methods to assess nature's recovery and guide human intervention.
Older parents frequently give help to their middle-aged offspring, and their perceptions about giving this help may affect their mental health, according to a team of researchers.
"We usually view the elderly as needy, but our research shows that parents ages 60 and over are giving help to their children, and this support is often associated with lower rates of depression among the older adults," said Lauren Bangerter, Ph.D. student in human development and family studies, Penn State.
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