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Back Matter

Front Matter

Excess Vitamin A Causes Birth Defects

Hubble Finds Surprises in Solar System

Ozone Hole Reemerges above the Antarctic

Controversy Sparks Panel

Optical Refrigeration Proves Really Cool

Nobel Prize for Genes That Shape Embryos

Genetic Sleuths Explain Insects’ Resistance

Outdoor Carbon Monoxide: Risk to Millions

After the Fall

Archaeology