Word: ultraviolet
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Everyone knows ozone is necessary for protection from the sun's harmful ultraviolet rays. The phenomenon of Arctic spring, when ozone levels over the Arctic suddenly drop, leaving a hole, is also well-known. But scientists still wonder exactly what ozone does, how it works, and where it goes. What controls the amount of ozone in our atmosphere...
...high-frequency controversies have one thing in common: in each case the electromagnetic waves or fields are too weak to affect human tissue by any well-understood mechanism. They are not known to disrupt living cells or alter DNA the way X-rays and ultraviolet radiation do. If these fields do indeed cause cancer, it is by a mechanism yet to be uncovered...
Scientists sort out X and Y carriers by tagging sperm with a fluorescent dye; under ultraviolet light, the X sperm glow brighter. Then the sperm are electrically charged -- positive for male, negative for female -- and a laser beam separates the two. Egg and appropriate sperm are mated in a glass dish, and the resulting embryo is implanted in a cow. The technique is about 90% reliable, which is pretty good odds for farmers to get more beef for the buck. Theoretically, a similar process could be developed for selecting human sex, though that ethical quandary does not appear imminent...
...have one in N-butyl butyrate, a chemical found in, of all things, cantaloupes, peaches and plums. In fruit, it contributes to overall flavor; in the atmosphere, it should help reduce mankind's siege of the ozone layer, in turn relieving the onslaught of cancer- and cataract-causing ultraviolet light...
Haynes, who is also associate professor of dermatology at the Medical School, said that although he first recommends sunscreen to patients with ultraviolet-related skin problems, Retin A is a possible next step...