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In Brief; December 1997; Scientific American Magazine; by Leutwyler; 3 Page(s) E = mc2, Really Converting matter into light is a simple trick compared with the flip side of Einstein¿s famed equation--or turning light into matter. To do so requires far more energy than physicists have managed to generate in the laboratory. But a team at the Stanford Linear Accelerator Center recently succeeded by aiming terawatt laser light into the accelerator¿s tightly focused electron beam. Some of the laser photons scattered backward and changed into high-energy gammaray photons. These photons in turn collided with other laser photons and produced electron-positron pairs. Vodka Woes Between 1984 and 1994 life expectancy in Russia for both men and women rose briefly and then plummeted. In a new study demographers led by D. A. Leon of the London School of Hygiene and Tropical Medicine credit the extra deaths to heavy drinking. The group found that rates of cancer-related deaths held steady during the decade it studied. And although tuberculosis became more prevalent and the health care system changed during the same period-- factors that may have affected life expectancy-- the incidence of deaths from alcohol-related diseases, accidents and violence rose most dramatically.
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