People take cars for walkable trips in part because such trips are boring and unattractive. Better design of the urban environment could create more pedestrians. Karen Hopkin reports...

Using shadows rather than light, researchers developed an experimental system for imaging cells that attaches to a cell phone and sends the data to diagnostic centers. Cynthia Graber reports...

For at least 1,500 years, Chinese masons have mixed sticky rice soup into their mortar for extra strength. Chemists now know why. Karen Hopkin reports...

Astrophysicists put the upper limit of the mass of the neutrino at 0.28 electron volts, based on the distribution of galaxies according to the 3-D Mega Z map. Steve Mirsky reports...