(Springer) The activity of online communities does not grow in line with the number of users, according to a model recently published in the European Physical Journal B.

(University of Innsbruck) The physicists of the University of Innsbruck and the Institute for Quantum Optics and Quantum Information (IQOQI) in Innsbruck have come considerably closer to their goal to investigate complex phenomena in a model system: They have realized a digital, and therefore, universal quantum simulator in their laboratory, which can, in principle, simulate any physical system efficiently. Their work has been published in the online issue of the journal Science.

(American Friends of Tel Aviv University) Combining a number of surveying techniques for the first time, Prof. Lev Eppelbaum and Dr. Youri Katz of Tel Aviv University say their integrated surveying techniques can be applied to any region in the world to more accurately identify riches beneath the earth’s surface — before expensive drilling and mining are necessary.

(Cornell University) In things thick and thin: Cornell physicists explain how fluids — such as paint or paste — behave by observing how micron-sized suspended particles dance in real time. Using high-speed microscopy, the scientists unveil how these particles are responding to fluid flows from shear — a specific way of stirring. (Science, Sept. 2).

(Harvard University) Exploiting a novel technique called phase discontinuity, researchers at the Harvard School of Engineering and Applied Sciences (SEAS) have induced light rays to behave in a way that defies the centuries-old laws of reflection and refraction. The discovery, published this week in Science, has led to a reformulation of the mathematical laws that predict the path of a ray of light bouncing off a surface or traveling from one medium into another — for example, from air into glass.

(Rush University Medical Center) Many common signs of aging, such as shaking hands, stooped posture and walking slower, may be due to tiny blocked vessels in the brain that can’t be detected by current technology.

(Cell Press) The findings reported online on Sept. 1 in Current Biology, a Cell Press publication, are in contrast to reports in adults showing that training at one task generally doesn’t translate into improved performance on other, substantially different tasks. They also may have important implications for improving success in school, particularly for those children at risk of poor outcomes, the researchers say.

(European Synchrotron Radiation Facility) An international team of scientists has developed a novel X-ray technique for imaging atomic displacements in materials with unprecedented accuracy. They have applied their technique to determine how a recently discovered class of exotic materials — multiferroics – can be simultaneously both magnetically and electrically ordered. Multiferroics are also candidate materials for new classes of electronic devices. The discovery, a major breakthrough in understanding multiferroics, is published in Science dated Sept. 2, 2011.

(American Chemical Society) With citizens’ groups seeking government regulation of foul-smelling ammonia emissions from large dairy farms, scientists today reported that adding natural plant extracts to cow feed can reduce levels of the gas by one-third while reducing the need to fortify cow feed with expensive protein supplements. They reported here at the 242nd National Meeting & Exposition of the American Chemical Society (ACS).

(Office of Naval Research) Senior officials from the Office of Naval Research (ONR) will join other industry leaders at the World Diversity Leadership Summit 2011 in New York City, Sept. 6-8. ONR Director of Research Dr. Michael Kassner and Dr. Anthony Junior, ONR’s education programs manager, will gather with influential representatives from across defense, public and private industry to discuss the implications of developing and maintaining a diverse workforce.