The Verification of Compliance with Arms-Control Agreements
Military activities in the U.S.S.R. can be unilaterally monitored by the U.S. with the aid of a wide spectrum of remote-sensing technologies, including high-resolution satellite photography
Volume 252, Issue 3
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Features
The Volcanoes and Clouds of Venus
Radar maps of Venus and chemical analysis of its atmosphere and crust imply the existence of active volcanoes. The sulfur gases they release form a global cover of sulfuric acid clouds
Chromosome Translocations and Human Cancer
Chromosomes in a cell of the immune system sometimes "trade" segments of DNA. This process can activate cancer-causing genes by placing them near genetic sequences that enhance their activity
The Hidden Dimensions of Spacetime
Spacetime, usually thought of as four-dimensional, may have as many as seven extra dimensions. Eleven-dimensional structures now under study might give a unified account of the four basic forces of nature
Why Whales Leap
The action, which is called breaching, seems to be purposeful. It is associated with the social aspects of whale life and probably serves in communication
A Neolithic Fortress and Funeral Center
Excavations at Hambledon Hill in southwestern England reveal that in about 3600 B. C. elaborate funeral rites began to be carried out there. As the funeral center decayed, a huge fortress was built
Ion Implantation of Surfaces
When foreign ions are embedded in the surface of a material, changes in structure and composition lead to novel surface properties. The technique is increasingly valuable both in industry and in fundamental research
The Chemistry of Garlic and Onions
A number of curious sulfur compounds underlie the odor of garlic and the crying brought on by slicing an onion. The compounds also account for medical properties long ascribed to garlic and onions