Global Climatic Change
Evidence suggests that production of carbon dioxide and methane from human activities has already begun to change the climate and that radical steps must be taken to halt any further change...
Features
The Turnover of Messenger RNA
The synthesis rate of many proteins is influenced more by how rapidly their messenger-RNA templates decay, or turn over, than by how rapidly the RNA's are synthesized. What regulates the decay?...
Quantum Interference and the Aharonov-Bohm Effect
These counterintuitive effects play important roles in the theory of electromagnetic interactions, in solid-state physics and possibly in the development of new microelectronic devices...
Astrocytes
Named for their starlike shape, these brain cells were once thought to be little more than passive support elements. Recent findings, however, implicate them in brain function, development and disease...
Free-Electron Lasers
Electrons can impart energy to light waves with the help of a magnetic field. The resulting intense beam can probe crystalline structures-and perhaps destroy missiles in space
Sensory Function in the Harbor Seal
Amphibious in its habits, the harbor seal divides its time between land and water. In the ocean the seal must navigate, locate prey and keep track of its pup; on land it gives birth, nurses its young and rests...
The Trireme Sails Again
It took years of detective work to reconstruct the fabled Greek warship. Sea trials indicate that the ship might indeed have performed the feats of speed attested to in ancient records
Children of the Garden Island
In 1955, 698 infants on the Hawaiian island of Kauai became participants in a 30-year study that has shown how some individuals triumph over physical disadvantages and deprived childhoods...
Departments
50 and 100 Years Ago: April 1989
Aids Counts
Flash Point
Points of View
Talking Tall
Irish Mist
It's a Pulsar!
Unsuperconductivity
Arctic Angst
Dirty Business
Beating the Spread
Deep Thought
Virus de Résistance
A Sparrow's Fall
Computerized Canaries
Multiple Choice
An Alliance for Progress?
The Burden of Proof
On Gossamer Wings
- Letters
Letters to the Editors, April 1989
- Recommended
Books, April 1989
- Amateur Scientist
The Amateur Scientist, April 1989
- Departments
Computer Recreations, April 1989
Fraud in Science: Causes and Remedies
