Bethany Barker

Every oyster farm in South Korea's southern coastal waters floats on a quiet environmental disaster. Roughly 24 million expanded polystyrene buoys bob among the country's 55 million aquaculture floats, and as they grind against waves, bake in ultraviolet light, and cycle between soaking and drying, they shed microscopic fragments directly into the waters where oysters grow.

Wound care has long faced an uncomfortable trade-off: dressings that protect the wound often fail to fight infection, while dressings loaded with antimicrobial agents can irritate surrounding tissue or lose their mechanical integrity before the wound has closed. A research team at the University of Tabriz in Iran now reports a way to have both.

The sulphur cosmos, Cosmos sulphureus, is one of those plants that gardeners and herbalists think they know well. A fast-growing member of the daisy family, it paints roadsides and gardens across the tropics in shades of yellow and orange, and it has long been valued in traditional medicine for its antioxidant-rich tissues.