Word: ultraviolet
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Loomis points out in the journal Science that vitamin D is no ordinary vitamin. Unlike the others, it occurs in virtually no natural foods.* It is synthesized in the skin under the influence of ultraviolet rays. The body needs vitamin D if it is to process calcium from food to make bone. Consequently, children need proportionately more vitamin D for their growing bones, and a D deficiency causes rickets...
...black skins. Many anthropologists have argued that dark skin evolved as a protection against sunburn and skin cancer. On the contrary, says Loomis: dark skin came first, and light skin evolved as a protection against a deficiency of vitamin D. Black skin allows only 3% to 36% of ultraviolet rays to pass, while white skin passes 53% to 72%. As early man moved north from the equatorial region, beyond the 40th parallel (roughly, the latitude of Madrid and Naples), Loomis argues, he got into a zone where black skin filters out too much ultraviolet...
...outside air. The rest of the building will make use of three separate air exhaust systems, not counting the systems used by the infectious disease center. Before the air from these other three system used by air from these other three systems is exhausted it will pass over an ultraviolet light source for sterilization...
Russian Bugs. Not worth it, says a study group led by Biologist Norman Horowitz of the California Institute of Technology. In a report in Science, the scientists argue that Mars has too little oxygen or water and too much ultraviolet radiation to support the growth of earthly organisms, and that Venus apparently has surface temperatures high enough to kill any earthly bugs. In any event, the report says, there is little chance that organisms entrapped within solid structures in the spacecraft could work their way free. Thus it is important only to kill microorganisms on the exposed surfaces...
...your partner's smooth motion becomes a panorama of frozen positions superimposed on each other. Soon an IBM computer will be moved in to help control the blinking red and blue lights. And if you take your date over to a corner, about all you can see in the ultraviolet light is her glowing blouse and nail-polish...