The Mortality of Men and Women
The tendency of women to live longer than men is increasing. The study of differences in the death rates of the sexes may hold clues to the prevention and treatment of many diseases
Volume 198, Issue 2
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Features
Strong Magnetic Fields
Physicists are building electromagnets whose fields compare with TNT in their concentration of energy. The resulting forces can explode the massive metal coils which produce them
The Metabolism of Ruminants
How is a cow able to digest the tough cellulose of plants? It does so with the help of four stomachs and microorganisms which both break down its food and provide it with vitamins
Ancient Temperatures
The ratio of the oxygen isotopes in a fossil shell reflects the temperature of the water in which the shell grew. This "thermometer" is now used to study the climate of the past
The Juvenile Hormone
The larva of an insect makes a hormone which keeps it from changing into a pupa until it has reached its full growth. Recent experiments with this substance have produced both dwarf and giant adult insects
The Discovery of Fission
In 1939 Otto Hahn and Fritz Strassmann announced that uranium nuclei "burst" when they are bombarded with neutrons. How they came to this conclusion is a classic example of the nature of science
Ballistocardiography
When the heart ejects blood, it recoils and shakes the whole body. Similar vibrations are caused by the impact of the blood. Records of these vibrations may have experimental and clinical usefulness
Prehistoric Man in the Grand Canyon
In an oasis at the bottom of the Canyon live the Havasupai Indians, who have now been linked to a vanished people who settled the surrounding plateau in the seventh century A.D.