Word: ck
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Uniformed guards with dogs kept a wary watch on the tent city erected by youthful environmentalists at the abandoned airport of Skarpnäck, but the violent demonstrations the police feared never came. Instead, the students put on gentle "eco-skits" to dramatize "eco-catastrophes." In one, for example, a girl painted as a skeleton and accompanied by drums and cymbals danced a warning about the radioactive fallout from French nuclear-bomb tests in the Pacific. Total damage to property caused by such activities: one broken window...
...molecular level. In their investigations, some used the electron microscope, which revealed details of structure invisible to ordinary optical instruments. Others specialized in X-ray crystallography, a technique for deducing a crystallized molecule's structure by taking X-ray photographs of it from different angles. Physicist Max Delbrück turned to nature for his investigative tools: bacteriophages (literally, "bacteria eaters"), tiny parasitic viruses that invade their host bacteria and rob them of their genetic heritage...
...Salvador Luria, 57, washing the breakfast dishes in Lexington, Mass., was incredulous when a neighbor interrupted to report what he had just heard over the radio. Dr. Alfred Hershey, 60, also was skeptical when word reached him at Cold Spring Harbor, N.Y. Dr. Max Delbrück, 63, was disgruntled; it was only 5 a.m. in Pasadena when a reporter called him. Telegrams from Stockholm soon confirmed the news. The three biologists (only Luria is an M.D.) had been jointly awarded the 1969 Nobel Prize in Physiology and Medicine for their work between 1940 and 1952 in microbiology and genetics...
...Luria, from Italy, met at Vanderbilt University in 1940 and began to cooperate in their studies of bacteriophages. Luria soon discovered that mutations (a variation in characteristics from one generation to the next) occurred in the viruses, and that these changes were passed on to succeeding generations. Delbrück found that the genetic materials of different kinds of viruses infecting the same cell sometimes combined, producing a new and different kind of virus...
Michigan-born Hershey, who began exchanging information with Delbruck and Luria in 1942, found more conclusive evidence for the genetic recombination that Delbrück had discovered. In 1952, Hershey proved that the virus, which consists simply of nucleic acid (DNA) surrounded by a coat of protein, leaves its coat behind as it invades a cell. So it must be the DNA that contains the genetic information...