The Verification of a Comprehensive Nuclear Test Ban
Networks of seismic instruments could monitor a total test ban with high reliability. Even small clandestine explosions could be identified even If extreme measures were taken to evade detection
Volume 247, Issue 4
You are currently logged out. Please sign in to download the issue PDF.
Features
Calcium in Synaptic Transmission
A current of calcium ions triggers the passage of signals from one nerve cell to another. The process is studied in a synapse (a neuronal junction) hundreds of times a synapse's usual size
Charge-Coupled Devices in Astronomy
Microelectronic technology has presented astronomers with a sensitive new radiation detector that is expected to improve the accuracy of many crucial observations
Artificial Intelligence
Computer programs not only play games but also process visual information, learn from experience and understand some natural language. The most challenging task is simulating common sense
Magnetic Fluids
When small ferromagnetic particles are suspended in a liquid carrier, the resulting "ferrofluid" exhibits unique properties that are intuitively baflling as well as technologically useful
Tidal Bores
A bore is the hydraulic analogue ofa sonic boom: a moving wall of water that carries the tide up some rivers that empty into the sea. For several hours after it passes the river rows upstream
How Honeybees Find a Home
In most of the Temperate Zone a new colony of honeybees must locate a snug shelter in order to survive the winter. The search is carried out by the older "scout" bees with remarkable rigor
Historical Eclipses
Reliable records of solar and lunar eclipses go back as far as 750 B.C. They bear on such questions as whether the sun is shrinking or the earth is not spinning as fast as it once did