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Emerging technologies that reduce the costs of making iron and steel may help smaller American mills to counter stiff foreign competition, but entirely new processing techniques are needed for the long term
When a rod cell in the retina absorbs light, a cascade of reactions results in a nerve signal. That cascade has now been worked out in molecular detail. A key intermediate is a protein called transducin
Why are they so narrow and dark? Findings trom the Voyager 2 encounter suggest that the austere ring system may be only a fleeting stage in a continuing saga of creation and destruction
Most manmade structures designed to protect these landforms along the Atlantic and Gulf coasts of the US. eventually fail. It might often be wiser not to interfere with the course of natural events
A bacterium transmitted to human beings by the bite of a deer tick causes this hazard of summertime. Interleukin-l, an immune-system regulator, may mediate its potentially serious arthritis-like symptoms
The electronlike particles called muons can catalyze nuclear fusion reactions, eliminating the need for powerful lasers or high-temperature plasmas. The process may one day become a commercial energy source
Many plants are almost perfectly engineered to capture pollen from the wind. Cones, flower clusters and other structures channel the airflow-and sperm-producing pollen-toward reproductive surfaces
Working with sun-dried mud brick and mud mortar, masons in ancient Egypt, Mesopotamia and the Levant built arches and vaults that were graceful as well as durable. Their methods are worth studying today