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A new strain of MRSA has been identified in cows' milk and in people, but don't stop drinking milk - the bug is killed off in pasteurisation. However, the strain evades detection by standard tests used by some hospitals to screen for MRSA (methicillin-resistant Staphylococcus aureus), potentially putting people at risk. Laura Garcia Alvarez, then at the University of Cambridge, and colleagues were studying infections in British cows when they discovered antibiotic-resistant bacteria that they thought were MRSA. However, tests failed to identify the samples as any known strains of the superbug. Sequencing the mystery bacteria's genomes revealed a previously unknown strain of MRSA with a different version of a gene called MecA. The new strain was also identified in samples of human MRSA, and is now known to account for about 1 per cent of human MRSA cases.

The lushest patches of some jungles are rooted in enigmatic black soil - with unexpected origins

It's not quite Cyclops, the sci-fi superhero from the X-Men franchise whose eyes produce destructive blasts of light, but for the first time a laser has been created using a biological cell. The human kidney cell that was used to make the laser survived the experience. In future such "living lasers" might be created inside live animals, which could potentially allow internal tissues to be imaged in unprecedented detail. It's not the first unconventional laser. Other attempts include lasers made of Jell-O and powered by nuclear reactors (see box below). But how do you go about giving a living cell this bizarre ability? Typically, a laser consists of two mirrors on either side of a gain medium - a material whose structural properties allow it to amplify light. A source of energy such as a flash tube or electrical discharge excites the atoms in the gain medium, releasing photons. Normally, these would shoot out in random directions, as in the broad beam of a flashlight, but a laser uses mirrors on either end of the gain medium to create a directed beam. As photons bounce back and forth between the mirrors, repeatedly passing through the gain medium, they stimulate other atoms to release photons of exactly the same wavelength, phase and direction. Eventually, a concentrated single-frequency beam of light erupts through one of the mirrors as laser light.

ScienceDaily (July 27, 2011) - Using a measurement of the clustering of the galaxies surveyed, plus other information derived from observations of the early universe, researchers have measured the Hubble constant with an uncertainly of less than 5 percent. The new work draws on data from a survey of more than 125,000 galaxies.

Babies born to mothers who were stressed during pregnancy grow up less able to cope with stress themselves, researchers believe.

It seems that Americans are in the midst of a raging epidemic of mental illness, at least as judged by the increase in the numbers treated for it. The tally of those who are so disabled by mental disorders that they qualify for Supplemental Security Income (SSI) or Social Security Disability Insurance (SSDI) increased nearly two and a half times between 1987 and 2007-from one in 184 Americans to one in seventy-six. For children, the rise is even more startling-a thirty-five-fold increase in the same two decades. Mental illness is now the leading cause of disability in children, well ahead of physical disabilities like cerebral palsy or Down syndrome, for which the federal programs were created.

"Men have forgotten this truth," said the fox. "But you must not forget it. You become responsible, forever, for what you have tamed." -Antoine de Saint Exupéry, The Little Prince

Life must have begun with a simple molecule that could reproduce itself - and now we think we know how to make one

Apply the electrodes... Externally modulating the brain's activity can boost its performance. The easiest way to manipulate the brain is through transcranial direct current stimulation (tDCS), which involves applying electrodes directly to the head to influence neuron activity with an electric current. Roi Cohen Kadosh's team at the University of Oxford showed last year that targeting tDCS at the brain's right parietal lobe can boost a person's arithmetic ability - the effects were still apparent six months after the tDCS session (newscientist.com/article/dn19679). More recently, Richard Chi and Allan Snyder at the University of Sydney, Australia, demonstrated that tDCS can improve a person's insight. The pair applied tDCS to volunteers' anterior frontal lobes - regions known to play a role in how we perceive the world - and found the participants were three times as likely as normal to complete a problem-solving task (newscientist.com/article/dn20080). Brain stimulation can also boost a person's learning abilities, according to Agnes Flöel's team at the University of Münster in Germany. Twenty minutes of tDCS to a part of the brain called the left perisylvian area was enough to speed up and improve language learning in a group of 19 volunteers (Journal of Cognitive Neuroscience, DOI: 10.1162/jocn.2008.20098). Using the same technique to stimulate the brain's motor cortex, meanwhile, can enhance a person's ability to learn a movement-based skill (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0805413106).

An international team of scientists has developed a novel X-ray technique for imaging atomic displacements in materials with unprecedented accuracy, using a recently discovered class of exotic materials - multiferroics - that can be simultaneously magnetically and electrically ordered. Multiferroics are also candidate materials for new classes of electronic devices. The researchers are from the European Synchrotron Radiation Facility (ESRF) in Grenoble (France), the University of Oxford, and the University College London.

Traditional methods of transmitting data, such as fibre optics or laser-based radar, require roughly 100 photons to transmit a single bit of data. Now a team led by Saikat Guha at Raytheon BBN Technologies in Cambridge, Massachusetts, say they can transmit 10 bits on a single photon - a 1000-fold improvement.

In 1967, Simon Kochen and Ernst Specker proved mathematically that even for a single quantum object, where entanglement is not possible, the values that you obtain when you measure its properties depend on the context. So the value of property A, say, depends on whether you chose to measure it with property B, or with property C. In other words, there is no reality independent of the choice of measurement. It wasn't until 2008, however, that Alexander Klyachko of Bilkent University in Ankara, Turkey, and colleagues devised a feasible test for this prediction. They calculated that if you repeatedly measured five different pairs of properties of a quantum particle that was in a superposition of three states, the results would differ for the quantum system compared with a classical system with hidden variables. That's because quantum properties are not fixed, but vary depending on the choice of measurements, which skews the statistics. "This was a very clever idea," says Anton Zeilinger of the Institute for Quantum Optics, Quantum Nanophysics and Quantum Information in Vienna, Austria. "The question was how to realise this in an experiment." Now he, Radek Lapkiewicz and colleagues have realised the idea experimentally. They used photons, each in a superposition in which they simultaneously took three paths. Then they repeated a sequence of five pairs of measurements on various properties of the photons, such as their polarisations, tens of thousands of times. A beautiful experiment They found that the resulting statistics could only be explained if the combination of properties that was tested was affecting the value of the property being measured. "There is no sense in assuming that what we do not measure about a system has [an independent] reality," Zeilinger concludes.

ScienceDaily (June 27, 2011) - While the U.S. Food and Drug Administration notes "some concern" with the controversial chemical BPA, and many other countries, such as Japan and Canada, have considered BPA product bans, disagreement exists amongst scientists in this field on the effects of BPA in animals and humans. The latest research from the University of Missouri shows that BPA causes male deer mice to become demasculinized and behave more like females in their spatial navigational abilities, leading scientists to conclude that exposure to BPA during human development could be damaging to behavioral and cognitive traits that are unique to each sex and important in reproduction.

ScienceDaily (July 5, 2011) - Have you heard the saying "You only remember what you want to remember"? Now there is evidence that it may well be correct. New research from Lund University in Sweden shows that we can train ourselves to forget things.

A new study of twins released online on Monday marked an important shift in thinking about the causes of autism.