Imaging shows the Smilodon bite had a narrow jaw which restricted its killing behavior. In public imagination, the sabre-toothed cat Smilodon ranks alongside Tyrannosaurus rex as the ultimate killing machine. Powerfully built, with upper canines like knives, Smilodon was a fearsome predator of Ice-Age America's lost giants.

When an adult suffers a cardiorespiratory arrest the rapid application of an electrical discharge with a defibrillator can avoid sudden death in many cases. Nevertheless, defibrillation also has its impediment or enemy: time. For every minute that passes from the moment of the attack, the possibilities of survival drop by 10%. This is why, in order to avoid avoidable deaths, more and more easy-to-handle, automatic defibrillators are being designed, sold and installed.

Scientists at the University of Missouri-St. Louis used DNA sequences from feather lice to study how island populations of their host, the Galápagos Hawk might have colonized the Galápagos islands, home to the endangered and declining raptor.

An unprecedented development plan to link South America’s economies through new transportation, energy and telecommunications projects could destroy much of the Amazon rainforest in coming decades, according to a new study by Conservation International (CI) scientist Tim Killeen.

A combined treatment with rapamycin and Gleevec might reverse the effects of portal hypertension in patients with chronic liver disease, according to the results of a new study on rats. The study is in the October issue of Hepatology, a journal published by John Wiley & Sons on behalf of the American Association for the Study of Liver Diseases (AASLD). The article is also available online at Wiley Interscience (http://www.interscience.wiley.com/journal/hepatology).

Some benefits of motherhood are intangible, but one has been validated through biostatistical research: women who bear children have a reduced risk of developing breast cancer. In Seattle, Washington, researchers at the University of Washington and Fred Hutchinson Cancer Research Center believe they have identified a source of this protective effect: fetal cells “transplanted” to the mother before birth.

The first significant genetic finding in premenstrual dysphoric disorder (PMDD) has now been reported. PMDD is a very severe form of the more commonly known premenstrual syndrome, or PMS. PMDD is heritable, affects 5-8% of women, and is associated with severe emotional and physical problems, such as irritability, marked depressed mood, anger, headaches, weight gain and more, to such an extent that quality of life is seriously impacted. Previously, researchers have shown that women with PMDD have an abnormal response to normal hormone levels and, thus, are differentially sensitive to their own hormone changes. Huo and colleagues now report their new findings, which link PMDD with common variants in the estrogen receptor alpha gene, in an article scheduled for publication in the October 15th issue of Biological Psychiatry.