Increased schooling across sub-Saharan Africa may be lowering new HIV infections among younger adults, according to sociologists, suggesting a shift in a decades-long trend where formal education is considered an AIDS risk factor.

Researchers are describing a long-awaited advance toward applying the marvels of nanotechnology in the battle against cancer. They have developed the first hollow gold nanospheres — smaller than the finest flecks of dust — that search out and "cook" cancer cells. The cancer-destroying nanospheres show particular promise as a minimally invasive future treatment for malignant melanoma, the most serious form of skin cancer, the researchers say. Melanoma now causes more than 8,000 deaths annually in the United States alone and is on the increase globally.

One minute, he's a strapping 40-year-old with an enviable cholesterol level, working out on his treadmill.

Relying on principles similar to those that cause Jell-O to congeal into that familiar, wiggly treat, University of Michigan researchers are devising a new method of detecting nitric oxide in exhaled breath.