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Nickel's back, this time the oxide under pressure becomes electrically conducting, The Alchemist learns, while damaged graphene could lead to batteries that can be charged in minutes instead of hours. In medical, structural studies offer new clues to combating that ever-present disease tuberculosis while revelations about ethanol metabolism and DNA damage hint at why Native Americans suffer a greater risk of cancer of the esophagus. Meanwhile, in the lab, we hear that DNA can now be used to code up gold crystalline nanoparticles. Finally, lecture news from the Kavli Foundation and the American Chemical Society.




Edward Yu and colleagues in the Ames Laboratory at Iowa State University have described the structure of a regulator that controls the expression of a protein pump that allows the TB-causing microbe Mycobacterium tuberculosis to get rid of different antibiotics, an ability which endows certain strains of the bacteria with drug resistance. “It is obvious that the emergence of these drug-resistant TB strains has evolved into a major threat and challenges our global prospects for TB control,” Yu and colleagues explain. “Thus, knowledge of the molecular mechanisms underlying drug resistance in M. tuberculosis is essential for the development of new strategies to combat this disease.





Alcohol consumption is a risk factor for the development of certain types of cancer. However, understanding why that might be has remained elusive. Now, Silvia Balbo suggests that a new study could have implications for hundreds of millions of drinkers of Asian descent. Balbo works with cancer prevention expert Stephen Hecht at the University of Minnesota. Speaking at the 244thNational Meeting & Exposition of the American Chemical Society in Philadelphia, she explained how acetaldehyde formed by natural metabolism of the ethanol from alcoholic beverages causes damage to DNA. “Acetaldehyde attaches to DNA in humans - to the genetic material that makes up genes - in a way that results in the formation of a ‘DNA adduct.’ It’s acetaldehyde that latches onto DNA and interferes with DNA activity in a way linked to an increased risk of cancer,” she said. One in three people of Asian descent, which includes Native Americans and Native Alaskans have a variant on the enzyme alcohol dehydrogenase, which otherwise converts acetaldehyde to the relatively harmless acetate, meaning they have a greater risk of esophageal cancer.





Researchers in China and the USA have demonstrated how gold nanoparticles can be controlled by DNA. Jinghong Li from the Tsinghua University Beijing and colleagues were able to use short strands of DNA to template the formation of well-define nanoparticles. Without the DNA their preparative steps simply led to agglomerations rather than crystalline products. "Our work could provide a new method for synthesizing nanoparticles with predictable structures with fine-tuned morphologies for widespread applications," the team says. "Nanoparticles with complex shapes and rough surfaces have recently been shown to have enhanced performance as catalytic components and support materials for analytical processes like Surface-enhanced Raman Spectroscopy (SERS). They are also better absorbed by cells."





The Kavli Foundation and the American Chemical Society are to launch a sponsored lecture series in 2013 to highlight the outstanding work of young chemical scientists at ACS national meetings. “We’re thrilled that The Kavli Foundation has chosen to sponsor another important series of Presidential Lectures at our national meetings,” said ACS President Bassam Shakhashiri. "We share the foundation’s commitment to recognizing and promoting the achievements of the emerging young minds in our science and their efforts to create a sustainable future for our planet."





Squeeze nickel oxide hard enough and it reverts to a metallic, electrically conducting phase, according to results from Carnegie Institute of Science. “Physicists have predicted for decades that the nickel oxide would transition from an insulator to a metal under compression, but their predictions have not previously been confirmed,” says team leader Viktor Struzhkin. 240 gigapascals is enough to convert micrometer-thin crystal samples of the oxide into a conducting phase. At that pressure electrical resistance drops by three orders of magnitude indicating a shift from semiconducting oxide to a metallic state. The discovery adds to our theoretical understanding of such changes and could ultimately allow materials scientists to design specific characteristics into novel substances.





Damaged graphene sheets can act as an anode in a rechargeable battery that take a fraction of the time to recharge compared to conventional lithium-ion batteries, according to research from Rensselaer Polytechnic Institute. Nikhil Koratkar and colleagues have deliberately added imperfections - defects - to graphene "paper", which they say can replace the standard graphite anode to good effect in a lithium battery. The team explains that the lithium ions can exploit the presence of the defects, the cracks and pores, in the graphene sheet to traverse the sheet much more rapidly than they otherwise would. The next step for this research project is to pair the graphene anode material with a high-power cathode material to construct a full battery, the team says.