The Real Threat of Nuclear Smuggling

Although many widely publicized incidents have been staged or overblown, the dangers of even a single successful diversion are too great to ignore.

Caloric Restriction and Aging

Eat less, but be sure to have enough protein, fat, vitamins and minerals. This prescription does wonders for the health and longevity of rodents. Might it help humans as well?

Technology and Economics in the Semiconductor Industry

Although the days of runaway growth may be numbered, their passing may force chipmakers to offer more variety

Neural Networks for Vertebrate Locomotion

The motions animals use to swim, run and fly are controlled by specialized neural networks. For ajawless fish known as the lamprey, the circuitry has been worked out

Cleaning Up the River Rhine

Intensive international efforts are reclaiming the most important river in Europe

The Evolution of Continental Crust

The high-standing continents owe their existence to the earth's long history of plate-tectonic actty

Working Elephants

They earn their keep in Asia by providing an ecologically benign way to harvest forests

Explaining Everything