Primordial Deuterium and the Big Bang
Nuclei of this hydrogen isotope formed in the first moments of the big bang. Their abundance offers clues to the early evolution of the universe and the nature of cosmic dark matter
Volume 275, Issue 6
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Features
Creating Nanophase Materials
The properties of these ultrafine-grained substances, now found in a range of commercial products, can be custom-engineered
Cell Suicide in Health and Disease
Cells can—and often do—kill themselves, in a process known as apoptosis. This capacity is essential to the proper functioning of the body; flawed regulation may lie behind many diseases
Atmospheric Dust and Acid Rain
Emissions of acidic air pollutants have fallen dramatically. Why is acid rain still a problem? Atmospheric dust may be part of the answer
A Cricket Robot
Can a simple electromechanical system perform a complex behavior of a living creature? There was one sure way to find out
Daily Life in Ancient Egypt
Workmen and their families lived some 3,000 years ago in the village ow known as Deir el-Medina. Written records from the unusually well educated community off er fascinating descriptions of everyday activities
Why Freud isn't Dead
The Specter of Biological Weapons
States and terrorists alike have shown a growing interest in germ warfare. More stringent arms-control efforts are needed to discourage attacks