Soils may dictate the array of fall colors as much as the trees rooted in them, according to a forest survey out of North Carolina.

Approximately one-third of the world’s population is infected with Mycobacterium tuberculosis, the bacterium that causes TB, and an estimated 1.6 million people died of the disease in 2005. Currently, TB patients must adhere to a complex treatment regimen over a six- to nine-month period. This demanding schedule often results in patients skipping treatment doses, which has given rise to drug-resistant strains of M. tuberculosis, including multi-drug-resistant (MDR) and, more recently, extensively drug-resistant (XDR) TB.

The shortage of islet cells limits the development of islet transplantation. One new approach was reported in the October 21 issue of the World Journal of Gastroenterology because of its great significance in enhancing the output of islet cells. This article will undoubtedly bring benefit to diabetic patients.

The splendid leaf frog. A brightly coloured tropical frog under threat of extinction is the focus of a new research project hoping to better understand how environment and diet influence its development and behaviour.

Researchers at the University of Leeds have made a breakthrough in understanding a virus which poses one of the greatest global disease threats to wild carnivores including lions, African wild dogs and several types of seal.

The greatest mass extinction in Earth’s history also may have been one of the slowest, according to a study that casts further doubt on the extinction-by-meteor theory.

The larger worm in the top image is a hermaphrodite -- a worm with male and female organs -- while the worm on the bottom is male. Biologists at the Brain Institute at the University of Utah genetically manipulated the brains of hermaphrodite worms so they were attracted to other worms of the same sex. The study showed sexual orientation is wired in the worms' brains. Credit: Jamie White, University of Utah University of Utah biologists genetically manipulated nematode worms so the animals were attracted to worms of the same sex – part of a study that shows sexual orientation is wired in the creatures’ brains.

The genes that make a fruit fly's eyes red also produce red wing patterns in the Heliconius butterfly found in South and Central America, finds a new study by a UC Irvine entomologist.

It was hoped that as HIV treatment improved and as HIV-related public health initiatives encouraged people to be tested for the disease and seek care, that HIV-infected patients would seek care quickly. Unfortunately, a new study indicates that patients are actually sicker when they begin therapy. The study is published in the November 15 issue of Clinical Infectious Diseases, currently available online.