USC College computational biologist Peter Calabrese has developed a new model to simulate the evolution of so-called recombination hotspots in the genome.

Published March 5 in the early online edition of the Proceedings of the National Academy of Sciences, the mathematical model and its associated software bring much-needed rigor to evolutionary investigations of how natural selection acts on individual genes, said Calabrese, a research assistant professor of biological sciences.

People who develop dementia or Alzheimer's disease experience brain structure changes years before any signs of memory loss begin, according to a study published in the April 17, 2007, issue of Neurology®, the scientific journal of the American Academy of Neurology. Researchers say these findings may help identify people at risk of developing mild cognitive impairment (MCI), which leads to Alzheimer's disease.

As interest in the rising number of newly characterized microbial genomes mounts, powerful computational tools become critical for the management and analysis of these data to enable strategies for such challenges as harvesting the potential of carbon-neutral bioenergy sources and coping with global climate change.

The Integrated Microbial Genomes (IMG) data management system developed by the U.S. Department of Energy Joint Genome Institute (DOE JGI) addresses this challenge with the release of version 2.1. Released on the two-year anniversary of its launch, the content of IMG 2.1 is updated with new microbial genomes from National Center for Biotechnology Information’s (NCBI) Reference Sequence collection (RefSeq) latest release, Version 21.

A new light source based on fiber-optic technology promises to improve the inspection of food, produce, paper, currency, recyclables and other products. New research revealing this technology will be presented at the Optical Fiber Communication Conference and Exposition/National Fiber Optic Engineers Conference (OFC/NFOEC), being held March 25-29 in Anaheim, Calif.

Currently, industrial processes for inspecting foodstuffs and other items often use "line-scan" cameras, which record images of objects one line at a time, just as fax machines scan documents on a line-by-line basis. Rapid electronic processors then detect whether there are any problems with the items and instruct mechanical actuators (such as air jets) to separate out unsatisfactory items.

Scientists have identified four Antarctic glaciers that pose a threat to future sea levels using satellite observations, according to a study published in the journal Science.

Experts from the University of Edinburgh and University College London determined the effect that Antarctica and Greenland were having on global sea level in a comprehensive evaluation of the Earth’s ice sheets. They found that together these two ice-sheets were responsible for a sea level rise of 0.35 millimetres per year over the past decade – representing about 12 per cent of the current global trend.

However, despite recent attention that has focused on the importance of the Greenland ice sheet, the research shows that its glaciers are changing too erratically to establish a trend with confidence.

The cause of one notorious childhood disease, poliovirus, could be used to treat the ongoing threat of another childhood disease, neuroblastoma. In the March 15 issue of Cancer Research, researchers from Stony Brook University report that an attenuated -- or non-virulent -- form of poliovirus is effective in obliterating neuroblastoma tumors in mice, even when the mice had been previously vaccinated against the virus.

By its nature, poliovirus destroys the cells it infects in an attempt to replicate copies of itself. When released from the cells it kills, the replicated particles then attack surrounding cells.