Jengmin Kang

Editor’s summary Many researchers have tried to understand longevity in humans and what could be done to improve it. However, this is a difficult topic to study because it takes a long time to collect data on human life spans, and many different factors can contribute to mortality. One key distinction is between extrinsic mortality (violence, accidents, infections, etc.) and intrinsic mortality due to genetic mutations and/or aging-related diseases. Shenhar et al.

Cell Biology Sensing forces to control growth L. Bryan Ray How cells precisely respond to external cues to regulate growth during processes such as wound healing is not fully understood. Mukherjee et al. identified a central role of changes in membrane potential to allow such regulation. They found that in various mammalian cell lines, cellular biomass density, often assumed to be constant for a given cell type, was in fact variable.

Tectonics A map of how Tibet flows Angela Hessler The Tibetan Plateau, pictured here, is an important region for understanding continent-scale faulting and crustal deformation. PHOTO: ZHANG MENGYANG/GETTY IMAGES The Tibetan Plateau is the roof of the world, but it also cracks and bends more than any other place. Wright et al. compiled thousands of satellite radar images of the plateau to make the highest-resolution view available of its deforming surface.