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A new kind of alchemy sees demonized carbon dioxide resurrected as an oxygen source for speedy cyclic alkene conversions while laser beams guide atoms for future quantum interference devices. In medicine, the discovery of a protein made by TB but not present in current vaccines offers hope of a new approach to diagnosis and prevention. However, concerns are raised regarding the effect of anti-inflammatory analgesics on the efficacy of antidepressants. In energy news, solar goes organic and nudges up the efficiency. Finally, the American Chemical Society Public Service Award is announced for 2011.




A laser beam has been used for the first time to guide atoms much as photons are guided by an optical fiber. Writing in Nature Communications, Australian researchers explain that their discovery could have implications for future quantum devices that use guided matter waves. The work could also be used in an atom interferometer for making sensitive measurements of the earth's gravitational field for geophysics applications and geological exploration.





Both diagnosis and prevention of tuberculosis might be improved by the discovery of a protein secreted by tuberculosis bacteria. The protein secreted by Mycobacterium tuberculosis could become both marker of infection and target for a vaccine. The protein, EspC, triggers a much stronger immune response in people infected with the M. tuberculosis than any other molecule known, but is not present in the BCG vaccine commonly used to prevent TB. The new protein could be used in next-generation immune cell-based blood tests for TB, so-called interferon- gamma release assays. The fact that it is not released by the BCG vaccine also means that a diagnostic based on EspC could be highly sensitive and readily discriminate between BCG-vaccination and actual TB infection.





US researchers have demonstrated that anti-inflammatory drugs, such as ibuprofen, aspirin and naproxen, might reduce the effectiveness of antidepressant and anxiolytic medications, the selective serotonin reuptake inhibitors, or SSRIs. SSRIs, which include the likes of fluoxetine, citalopram and sertraline, are widely used to treat clinical depression, obsessive-compulsive disorder and anxiety disorders. Paul Greengard, Jennifer Warner-Schmidt and colleagues at The Rockefeller University point out that this surprising discovery could have important implications for sufferers of such mental illnesses who also have inflammatory conditions or chronic pain.





Organic offers many advantages over conventional semiconductors for solar-energy conversion technology. Among those advantages are low-cost, low-density and scalable surface area. However, organic also comes with a disadvantage: low efficiency. Many teams around the world are hoping to break this latter obstacle, and now US chemists have found that Stille coupling of two highly conjugated monomers can produce an organic polymer with a small band gap and high power conversion efficiency. Solar cells built from these polymers were approximately 6% efficient, which is relatively high for organic materials and inching towards the 10% tipping point.





Jeremy Berg, director of the National Institute of General Medical Sciences at the National Institutes of Health (NIH) and Norman Neureiter, senior advisor to the Center for Science Diplomacy at the American Association for the Advancement of Science are to be the 2011 recipients of the American Chemical Society's Public Service Award for their vision and leadership in science and engineering policy. "I am very pleased that ACS is recognizing two scientists who have dedicated their talents to public service," ACS President Nancy Jackson said. "ACS created its Public Service Award to recognize the kind of leadership that Doctors Berg and Neureiter exemplify, and it is fitting that they will be joining the list of distinguished recipients," she adds.





Carbon dioxide can be used as a co-factor for catalytic reactions allowing cyclic alkenes to be converted with higher conversion rates at lower pressures, according to chemists in South Korea. Sang-Eon Park and colleagues at Inha University, in Incheon, used carbon nitrides containing surface groups to activate carbon dioxide and thence to promote oxidation. Carbon dioxide has been investigated in the past as a "green" chemistry reagent or solvent in dense and supercritical form, respectively. However, it can act as an oxygen source even at low pressure, Park explains. Further spectroscopic and computational studies are now under way to glean details of the precise mechanism allowing the gas to behave in this way and so help the researchers fine tune the oxidation reactions and perhaps even extend the range of reactions amenable to this approach.