A colleague approached Ernesto Di Maio, a materials scientist in Naples, Italy, and an expert…

Asanda Zondi received a startling phone call last Thursday, with orders to make her way…

Hospital and emergency room patients diagnosed with cannabis use disorder — defined as an inability…

Susan F. Wood, a women’s health expert who resigned in protest from the Food and…

Two weeks into President Trump’s sweeping freeze on foreign aid, H.I.V. groups abroad have not…

Ernest Drucker, a pioneering public-health researcher who approached drug addiction with compassion, invigorated needle-exchange programs…