Word: ultraviolet
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Dates: during 1970-1979
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Finally-after several experiments -Chakrabarty discovered that irradiating the host organisms with ultraviolet light after plasmid transfer induced a genetic cross-linking that fixed the new genes in place and produced stable bacteria with a healthy appetite for oil. The new microbe, to which Chakrabarty gives the jawbreaking description "multi-plasmid hydrocarbon-degrading pseudomonas," can digest about two-thirds of the hydrocarbons involved in an oil spill. The new microbes have been tested only in the laboratory, where a pinch of microbes will eat an eyedropper of oil in a matter of days. This may seem slow...
...could be masses of well-preserved plastic bottles, containers, bags and wrappings. That is because plastics resist natural processes of decay almost indefinitely. To make the material go away when it is thrown away, scientists in Germany have developed a type of plastic that disintegrates when exposed to the ultraviolet rays in sunlight. But it has a hitch: the sun does not distinguish between unopened plastic containers and discards...
...past two years, several scientists have become concerned about fluorocarbon propellants, used in aerosol sprays, drifting up through the stratosphere. In their doomsday scenario, these fluorocarbons break down to form chlorine atoms that gradually destroy the ozone shield protecting the earth from an overdose of the sun's ultraviolet rays; this, in turn, increases the risk that humans down on earth will develop skin cancer...
...Oregon last week heeded the warning by scientists that some gases in aerosol sprays can destroy the ozone layer in the stratosphere that protects earth from an overdose of the sun's ultraviolet rays (TIME, Oct. 7). The state legislature banned the sale after March 1, 1977, of aerosol cans that use chlorofluorocarbon compounds as propellants-mainly hair sprays, oven cleaners, insecticides and deodorants. Opponents of the measure claim that there is no hard evidence that the chlorofluorocarbons actually damage the ozone layer. But the Oregon lawmakers preferred not to wait for final proof, and the bill is expected...
Dermatologists at M.G.H. and the All-gemeines Krankenhausen in Vienna have modernized that technique. The new treatment combines the use of a drug called methoxsalen, which is extracted from the Egyptian plant, and an extraordinary high-intensity ultraviolet light. First the dermatologists have the patient swallow methoxsalen pills. Then they stand him in a telephone-booth-size closet lined with 48 of the special ultraviolet tubes. The patient stays in the booth from eight to 30 minutes, depending upon his degree of skin coloration...