Topological structure of a quantum-mechanical knot soliton: the white ring is the core of the soliton (field pointing down), and the surrounding colored bands define a set of nested tori that illustrate the linked structure of its field lines. The boundary of the knot lies near the dark grey lines (field pointing up). Image credit: David Hall.
Artist's illustration shows a monoclonal antibody (green) developed by scientists at the University of Alabama binding to a 'death cell receptor' on a cancer cell (top left). This triggers the cell's inbuilt suicide program (apoptosis) Photograph: Courtesy of Emiko Paul and Quade Paul/ Echo Medical Media; Ron Gamble/UAB Insight/Science