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ScienceDaily (June 9, 2011) - On rare occasion, the light-sensing photoreceptor cells in the eye misfire and signal to the brain as if they have captured photons, when in reality they haven't. For years this phenomenon remained a mystery. Reporting in the June 10 issue of Science, neuroscientists at the Johns Hopkins University School of Medicine have discovered that a light-capturing pigment molecule in photoreceptors can be triggered by heat, as well, giving rise to these false alarms.

"Die Ergebnisse zeigen, dass das angeborene Fluchtverhalten auf Kohlendioxid in Fruchtfliegen je nach ihrem Sättigungszustand von zwei parallelen neuronalen Schaltkreisen gesteuert wird. „Ist die Fliege hungrig, verlässt sie sich nicht mehr auf die "direkte Leitung", sondern benutzt Hirnzentren, mit denen sie interne und äußere Signale abwägen und eine ausgewogene Entscheidung treffen kann", erklärt Grunwald-Kadow und fügt hinzu: „Es ist faszinierend, in welchem Ausmaß der Stoffwechsel und Hunger die verarbeitenden Prozesse im Gehirn beeinflussen." ***** Lasse B. Bräcker, K.P. Siju, Nelia Varela, Yoshinori Aso, Mo Zhang, Irina Hein, Maria Luisa Vasconcelos, Ilona C. Grunwald Kadow Essential role of the mushroom body in context dependent CO2 avoidance in Drosophila Current Biology, 13 June 2013 Max-Planck-Institut für Neurobiologie"

"We have sensitive body parts wired to the same area of the brain as rodents' fine-tuned whiskers. In people, "stimulating the fingers, lips or face in general could all have a similar effect," says UCI doctoral student Melissa Davis, co-author of the study, which appears in the June issue of PLoS ONE. "It's gender-neutral," adds co-author Ron Frostig, professor of neurobiology & behavior. He cautions that the research, funded by the National Institutes of Health, is a first step, albeit an important one.... "with the potential for maybe doing things before a victim even reaches the emergency room.""

"Eine eindeutige Erklärung für diese Unterschiede in den Persönlichkeitstypen zwischen Stadt- und Landamseln haben die Wissenschaftler bis jetzt noch nicht. „Möglicherweise müssen Amseln in der schnelllebigen Stadtwelt permanent mit neuen Situationen zurechtkommen, wohingegen das Landleben mit seinen gleichförmigeren Abläufen verlässlichere Lebensbedingungen bietet", vermutet Catarina Miranda vom Max-Planck-Institut für Ornithologie in Radolfzell das Ergebnis. „Die Evolution scheint im Laufe der Besiedlung von Städten daher bestimmte Persönlichkeitstypen begünstigt zu haben", so Miranda. Diese Erklärung wird durch eine jüngst veröffentlichte Studie gestützt: Gene, die wahrscheinlich an der Ausprägung der hier untersuchten Verhaltensweisen beteiligt sind, zeigen in Stadtamseln eine andere Struktur als in den Waldamseln. Die Amselpersönlichkeit scheint also genetisch festgelegt und kann demnach durch Evolution während des Verstädterungprozesses verändert worden sein. ***** Ana Catarina Miranda, Holger Schielzeth, Tanja Sonntag & Jesko Partecke Urbanization and its effects on personality traits: a result of microevolution or phenotypic plasticity?, Global Change Biology, 19 June 2013 Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. http://www.ncbi.nlm.nih.gov/pubmed/23681984"

ScienceDaily (June 2, 2010) - Using high-throughput sequencing to map the locations of a common type of jumping gene within a person's entire genome, researchers at the University of Pennsylvania School of Medicine found extensive variation in these locations among the individuals they studied, further underscoring the role of these errant genes in maintaining genetic diversity.

"(PhysOrg.com) -- Imagine being able to drop a toothpick on the head of one particular person standing among 100,000 people in a stadium. It sounds impossible, yet this degree of precision at the cellular level has been demonstrated by researchers affiliated with the Johns Hopkins University Institute for NanoBioTechnology. Their study was published online in June in Nature Nanotechnology."

ScienceDaily (June 23, 2010) - In a study with implications for the advertising industry and public health organizations, UCLA neuroscientists have shown they can use brain scanning to predict whether people will use sunscreen during a one-week period even better than the people themselves can.

ScienceDaily (June 28, 2010) - An Australian National University-led team has developed the most efficient quantum memory for light in the world, taking us closer to a future of super-fast computers and communication secured by the laws of physics.

ScienceDaily (June 28, 2010) - Why are tropical forests so biologically rich? Smithsonian researchers have new evidence that the answer to one of life's great unsolved mysteries lies underground, according to a study published in the journal, Nature.

"Individuals whose diet includes more salad dressing, nuts, fish, poultry and certain fruits and vegetables and fewer high-fat dairy products, red meats, organ meats and butter appear less likely to develop Alzheimer's disease, according to a report posted online today that will appear in the June print issue of Archives of Neurology, one of the JAMA/Archives journals."

ScienceDaily (June 9, 2011) - New research just published in the journal Science by a team of chemists at the University of Georgia and colleagues in Germany shows for the first time that a mechanism called tunneling control may drive chemical reactions in directions unexpected from traditional theories.

ScienceDaily (June 4, 2011) - Do the principles of quantum mechanics apply to biological systems? Until now, says Prof. Ron Naaman of the Institute's Chemical Physics Department (Faculty of Chemistry), both biologists and physicists have considered quantum systems and biological molecules to be like apples and oranges. But research he conducted together with scientists in Germany, which appeared recently in Science, shows that a biological molecule -- DNA -- can discern between quantum states known as spin.

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

ScienceDaily (June 9, 2011) - Observations from NASA's Voyager spacecraft, humanity's farthest deep space sentinels, suggest the edge of our solar system may not be smooth, but filled with a turbulent sea of magnetic bubbles.

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.

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 21, 2011) - An important milestone in the direct measurement of the magnetic moment of the proton and its anti-particle has been achieved.

ScienceDaily (June 28, 2011) - A recent study from scientists at the Salk Institute for Biological Studies suggests that a strawberry a day (or more accurately, 37 of them) could keep not just one doctor away, but an entire fleet of them, including the neurologist, the endocrinologist, and maybe even the oncologist.