A profile of Dr. Oz.

On the importance of the human microbiome.

On geoengineering, a high risk/high reward fix for global warming.

Controversy over the alleged gold standard of forensic evidence.

On Lance Armstrong’s return to racing after cancer.

Inside a chess master’s fiefdom.

A profile of the (now former) director of the House of Dior, John Galliano.

“You can treat a lot of people, and India has,’’ says an epidemiologist working on TB. “But if you have tests that cause misdiagnosis on a massive scale you are going to have a serious problem. And they do.”