Earth

Cambridge, Mass. – August 23, 2012 – Applied physicists at the Harvard School of Engineering and Applied Sciences (SEAS) have created an ultrathin, flat lens that focuses light without imparting the distortions of conventional lenses.

At a mere 60 nanometers thick, the flat lens is essentially two-dimensional, yet its focusing power approaches the ultimate physical limit set by the laws of diffraction.

Cancer metastasis, the escape and spread of primary tumor cells, is a common cause of cancer-related deaths. But metastasis remains poorly understood. Studies indicate that when a primary tumor breaks through a blood vessel wall, blood's "stickiness" tears off tumor cells the way a piece of tape tears wrapping paper. Until now, no one knew the physical forces involved in this process, the first step in metastasis. Using a statistical technique employed by animators, scientists created a new computer simulation that reveals how cancer cells enter the bloodstream.

By affixing nanoscale gold spheres onto a microscopic bead of glass, researchers have created a super-sensor that can detect even single samples of the smallest known viruses. The sensor uses a peculiar behavior of light known as "whispering gallery mode," named after the famous circular gallery in St. Paul's Cathedral in London, where a whisper near the wall can be heard around the gallery.

Cities – with their concrete canyons, isolated greenery, and congested traffic – create seemingly chaotic and often powerful wind patterns known as urban flows. Carried on these winds are a variety of environmental hazards, including exhaust particles, diesel fumes, chemical residues, ozone, and the simple dust and dander produced by dense populations.

Analysis of small, repeating earthquakes in an Antarctic ice sheet may not only lead to an understanding of glacial movement, but may also shed light on stick slip earthquakes like those on the San Andreas fault or in Haiti, according to Penn State geoscientists.

"No one has ever seen anything with such regularity," said Lucas K. Zoet, recent Penn State Ph. D. recipient, now a postdoctoral fellow at Iowa State University. "An earthquake every 25 minutes for a year."

Boulder, Colo., USA – New Geology postings include understanding the "Mystery Interval" during the last deglaciation in the Northern Hemisphere; examining topographic change and recovery after the 2011 Tohoku-oki tsunami; asking whether self-mutilation or self-amputation in sea lilies was an adaptive response during the Paleozoic; discovering that powerfully erosive behavior can occur even on the lee side of a topographic barrier; and demonstrating for the first time that the PTB biotic crisis was probably triggered by enormous Plinian eruptions.

A new record of past temperature change in the tropical Atlantic Ocean's subsurface provides clues as to why the Earth's climate is so sensitive to ocean circulation patterns, according to climate scientists at Texas A&M University.

WASHINGTON – Scientists have long suspected that the Sun's 11-year cycle influences climate of certain regions on Earth. Yet records of average, seasonal temperatures do not date back far enough to confirm any patterns. Now, armed with a unique proxy, an international team of researchers show that unusually cold winters in Central Europe are related to low solar activity – when sunspot numbers are minimal. The freezing of Germany's largest river, the Rhine, is the key.

Scientists at the University of Cambridge have produced hydrogen, H2, a renewable energy source, from water using an inexpensive catalyst under industrially relevant conditions (using pH neutral water, surrounded by atmospheric oxygen, O2, and at room temperature).

Reducing tillage for some Central Great Plains crops could help conserve water and reduce losses caused by climate change, according to studies at the U.S. Department of Agriculture (USDA).

Research leader Laj Ahuja and others at the Agricultural Research Service (ARS) Agricultural Systems Research Unit at Fort Collins, Colo., superimposed climate projections onto 15 to 17 years of field data to see how future crop yields might be affected. ARS is USDA's chief intramural scientific research agency, and this work supports the USDA priority of responding to climate change.

Northwestern University scientists have connected 250 years of organic chemical knowledge into one giant computer network -- a chemical Google on steroids. This "immortal chemist" will never retire and take away its knowledge but instead will continue to learn, grow and share.

A decade in the making, the software optimizes syntheses of drug molecules and other important compounds, combines long (and expensive) syntheses of compounds into shorter and more economical routes and identifies suspicious chemical recipes that could lead to chemical weapons.

Knowing the position of missing oxygen atoms could be the key to cheaper solid oxide fuel cells with longer lifetimes. New microscopy research from the Department of Energy's Oak Ridge National Laboratory is enabling scientists to map these vacancies at an atomic scale.

Washington, D.C.—Carnegie scientists are the first to discover the conditions under which nickel oxide can turn into an electricity-conducting metal. Nickel oxide is one of the first compounds to be studied for its electronic properties, but until now scientists have not been able to induce a metallic state. The compound becomes metallic at enormous pressures of 2.4 million times the atmospheric pressure (240 gigapascals). The finding is published in Physical Review Letters.

Irvine, Calif. – Increased capture of natural gas from oil fields probably accounts for up to 70 percent of the dramatic leveling off seen in atmospheric methane at the end of the 20th century, according to new UC Irvine research being published Thursday, Aug. 23, in the journal Nature.

"We can now say with confidence that, based on our data, the trend is largely a result of changes in fossil fuel use," said chemistry professor Donald Blake, senior author on the paper.

(Edmonton) University of Alberta ecologist David Schindler has reviewed data from studies of controlling human-caused algae blooms in lakes and says controlling the input of the nutrient phosphorus is the key to fighting the problem.

Recent short-term algae studies claim that controlling the human input of both nitrogen and phosphorus into lakes must be reduced to control summer algae blooms.