FORENSICS -- Microbial detectives . . .
Bacteria from a decaying body can potentially tell investigators something about how long a person has been dead, and it's the focus of new research by Arpad Vass of Oak Ridge National Laboratory. Vass and colleagues are looking at the microbial population, which changes over time and creates a virtual script accented by peaks of activity. Each peak represents a different group of organisms, and, from that data, researchers can calculate how long a person has been dead. "What we'll have is the overall picture and a methodology for the entire decomposition process," Vass said. While there are other fairly effective approaches to determine time since death, this technique has an advantage because the microbes come directly from the body, and, short of embalming or cremation, no one can get rid of this particular "evidence." The project is funded by the Law Enforcement Innovation Center at the University of Tennessee. [Contact: Ron Walli, 865-576-0226; wallira@ornl.gov]
GENETICS -- New mice, new opportunities . . .
A mouse population that once totaled more than 200,000 is down to zero at Oak Ridge National Laboratory, but it's all part of the plan. Beginning in the next few weeks and continuing for several years, the mouse colony will be rederived from stocks of embryos frozen in special freezers chilled by liquid nitrogen. The stock consists of more than 900 strains, some dating back to the 1940s. Strains for which there is funding – about 300 -- will be brought back to life. The new mice will be housed in ORNL's brand new 30,000-square-foot pathogen-free Russell Laboratory for Comparative and Functional Genomics. Because the facility is sterile, ORNL will now be able to exchange its specially mutated mice with other research institutions and will be eligible for research dollars previously unavailable to ORNL [Contact: Ron Walli, 865-576-0226; wallira@ornl.gov]
TRANSPORTATION -- More practical fuel cell . . .
Low-cost corrosion-resistant metallic bipolar plates developed at Oak Ridge National Laboratory could make proton exchange membrane (PEM) fuel cells economical for use in automobiles and portable power units. As with other types of fuel cells, cost is a barrier to widespread use, but PEM fuel cells also must address power density because space under the hood is very limited in today's vehicles. These barriers could be overcome, however, as Mike Brady of ORNL's Metals & Ceramics Division has developed a new family of nickel-chrome alloys that form a protective and electrically conductive chrome-nitride surface on the bipolar plates. Use of thin metallic bipolar plates will reduce the size and weight of fuel cell stacks and increase the power density. This new breed of bipolar plates is being optimized for weight, electrical conductivity and corrosion resistance, and the plates are designed for low-cost manufacturing processes. The research is funded by DOE. [Contact: Ron Walli, 865-576-0226; wallira@ornl.gov]
PHYSICS -- Alternate path to success . . .
Results from low-energy collisions of neutron-rich unstable nuclei and nickel-64 could point to the recipe for making the super heavy elements that have eluded physicists for some 40 years. Experiments by Oak Ridge National Laboratory physicists Dan Shapira and Felix Liang have demonstrated an enhancement of the tunneling effect that permits two colliding nuclei to fuse into one nucleus at long distances. They accomplish this feat by increasing the number of neutrons, the "glue" that holds nuclei together, in the beam. In this case it was unstable nuclei of tin-132. This approach is in sharp contrast to the conventional approach of smashing stable isotopes with high beam current to compensate for the lower probability for tunneling. Shapira and Liang's work, which was published in the Oct. 15 (Volume 91, No. 15) issue of Physical Review Letters, represents another step in the quest for synthesizing super heavy elements. This knowledge is critical to understanding the distribution of elements in the universe. This unique measurement was made at ORNL's Holifield Radioactive Ion Beam Facility, the only facility in the world that could produce such heavy neutron-rich beams with sufficient energy and intensity. [Contact: Ron Walli, 865-576-0226; wallira@ornl.gov]