Cold War tensions and the polio vaccine was the first polio vaccine to receive approval of the U.S. government, and was used until 1961 in America, when the Sabin vaccine was recommended to replace it. Albert Sabin, a virologist who publicly disagreed with Salk and his killed vaccine, worked on creating a vaccine with live, attenuated vaccines. Despite Cold War tensions, in January, 1956 Mikhail Chumakov, the director of Moscow's Polio Research Institute, his wife and colleague Marina Voroshilova, and Anatoli Smorodentsev, traveled to the U.S. in order to study the Salk vaccine and visited the laboratory of Albert Sabin. With the clearance of the FBI, Sabin
By His Bootstraps By His Bootstraps "By His Bootstraps" is a 20,000 word science fiction novella by American writer Robert A. Heinlein. It plays with some of the inherent paradoxes that would be caused by time travel. The story was published in the October 1941 issue of "Astounding Science Fiction" under the pen name Anson MacDonald; the same issue has "Common Sense" under Heinlein's name. "By His Bootstraps" was reprinted in Heinlein's 1959 collection "The Menace From Earth", and in several subsequent anthologies, and is now available in at least two audio editions. Under the title "The Time Gate", it was also included