In a new poll from Gallup, 45 percent of U.S. adults said they had tried marijuana at least once in their lives.

Researchers reported earlier this year in the journal Frontiers of Public Health that up to 76 percent of the world's population may be overfat. Now these same researchers have focused their efforts on data from 30 of the top developed countries, with even more alarming findings that up to 90 percent of adult males and 50 percent of children may be overfat.

A nine-year-old South African child who was diagnosed with HIV infection at one month of age and received anti-HIV treatment during infancy has suppressed the virus without anti-HIV drugs for eight and a half years, scientists report. This case appears to be the third reported instance of sustained HIV remission in a child after early, limited anti-HIV treatment.

Scientists have developed a new way to make stimuli-responsive materials in a predictable manner. They used this method to design a new material, a mixture of carbon nanorings and iodine, which conducts electricity and emits white light when exposed to electricity. The team's new approach could help generate a range of reliable stimuli-responsive materials, which can be used in memory devices, artificial muscles and drug delivery systems, among other applications.