UA physicists have discovered how to change the crystal structure of graphene. The finding could lead to smaller and faster microprocessors.
A University of Arizona-led team of physicists has discovered how to change the crystal structure of graphene, more commonly known as pencil lead, with an electric field, an important step toward the possible use of graphene in microprocessors that would be smaller and faster than current, silicon-based technology. (more…)
Using ultra-fast laser pulses, a team of researchers led by UA assistant professor Vanessa Huxter has made the first detailed observation of how energy travels through diamonds containing nitrogen-vacancy centers – promising candidates for a variety of technological advances such as quantum computing.
A team of researchers led by University of Arizona assistant professor Vanessa Huxter has made the first detailed observation of how energy travels through diamonds that contain nitrogen-vacancy centers – defects in which two adjacent carbon atoms in the diamond’s crystal structure are replaced by a single nitrogen atom and an empty gap. (more…)
A new study shows that common mutant forms of the deadly JC polyomavirus are not responsible for the pathogen’s main attack, which causes a brain-damaging disease in immunocompromised patients called progressive multifocal leukoencephalopathy. But that finding raises the ominous question of what the mutants might be up to instead.
PROVIDENCE, R.I. [Brown University] — The JC polyomavirus is clearly opportunistic. It infects half the population but lethally destroys brain tissue only in immunocompromised patients — and it may be outright sneaky, too. Even as a new research paper allays fears that common mutant forms of the virus are the ones directly responsible for the disease’s main attack, that same finding raises new questions about what the mutants are doing instead. (more…)
The first detailed and complete picture of a protein complex that is tied to human birth defects as well as the progression of many forms of cancer has been obtained by an international team of researchers led by scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab). Knowing the architecture of this protein, PRC2, for Polycomb Repressive Complex 2, should be a boon to its future use in the development of new and improved therapeutic drugs.
“We present a complete molecular organization of human PRC2 that offers an invaluable structural context for understanding all of the previous biochemical and functional data that has been collected on this complex,” says Berkeley Lab biophysicist Eva Nogales, an electron microscopy expert who led this research. “Our model should also be an invaluable tool for the design of new experiments aimed at asking detailed questions about the mechanisms that enable PRC2 to function and how those mechanisms might be exploited.” (more…)
ANN ARBOR, Mich.— Researchers trying to herd tiny particles into useful ordered formations have found an unlikely ally: entropy, a tendency generally described as “disorder.”
Computer simulations by University of Michigan scientists and engineers show that the property can nudge particles to form organized structures. By analyzing the shapes of the particles beforehand, they can even predict what kinds of structures will form.
The findings, published in this week’s edition of Science, help lay the ground rules for making designer materials with wild capabilities such as shape-shifting skins to camouflage a vehicle or optimize its aerodynamics. (more…)
*Berkeley Lab Researchers Show the Way Forward for Improving Organic and Molecular Electronic Devices*
Future prospects for superior new organic electronic devices are brighter now thanks to a new study by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab). Working at the Lab’s Molecular Foundry, a DOE nanoscience center, the team has provided the first experimental determination of the pathways by which electrical charge is transported from molecule-to-molecule in an organic thin film. Their results also show how such organic films can be chemically modified to improve conductance.
“We have shown that when the molecules in organic thin films are aligned in particular directions, there is much better conductance,” says Miquel Salmeron, a leading authority on nanoscale surface imaging who directs Berkeley Lab’s Materials Sciences Division and who led this study. “Chemists already know how to fabricate organic thin films in a way that can achieve such an alignment, which means they should be able to use the information provided by our methodology to determine the molecular alignment and its role on charge transport across and along the molecules. This will help improve the performances of future organic electronic devices.” (more…)
Chemists at Brown University have created a triple-headed metallic nanoparticle that reportedly performs better and lasts longer than any other nanoparticle catalyst studied in fuel-cell reactions. The key is the addition of gold: It yields a more uniform crystal structure while removing carbon monoxide from the reaction. Results published in the Journal of the American Chemical Society.
PROVIDENCE, R.I. [Brown University] — Advances in fuel-cell technology have been stymied by the inadequacy of metals studied as catalysts. The drawback to platinum, other than cost, is that it absorbs carbon monoxide in reactions involving fuel cells powered by organic materials like formic acid. A more recently tested metal, palladium, breaks down over time. (more…)
*Berkeley Lab Researchers Identify Structure of Key Control Element Behind Protein Misfolding That Can Lead to Disease*
The gold standard for nanotechnology is nature’s own proteins. These biomolecular nanomachines – macromolecules forged from peptide chains of amino acids – are able to fold themselves into a dazzling multitude of shapes and forms that enable them to carry out an equally dazzling multitude of functions fundamental to life. As important as protein folding is to virtually all biological systems, the mechanisms behind this process have remained a mystery. The fog, however, is being lifted.
A team of researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab), using the exceptionally bright and powerful x-ray beams of the Advanced Light Source, have determined the crystal structure of a critical control element within chaperonin, the protein complex responsible for the correct folding of other proteins. The incorrect or “misfolding” of proteins has been linked to many diseases, including Alzheimer’s, Parkinson’s and some forms of cancer. (more…)
