Polio vaccine attenuated vaccine strains. In 1958, the National Institutes of Health created a special committee on live polio vaccines. The various vaccines were carefully evaluated for their ability to induce immunity to polio, while retaining a low incidence of neuropathogenicity in monkeys. Large-scale clinical trials performed in the Soviet Union in late 1950s to early 1960s by Mikhail Chumakov and his colleagues demonstrated safety and high efficacy of the vaccine. Based on these results, the Sabin strains were chosen for worldwide distribution. Fifty-seven nucleotide substitutions distinguish the attenuated Sabin 1 strain from its virulent parent (the Mahoney serotype), two nucleotide substitutions
6 Songs for Bruce 6 Songs for Bruce 6 Songs for Bruce, also commonly known as 4-Track Demo, is an early single-sided demo cassette tape by American rock band Soundgarden. The band, at the time a three-piece named Sound Garden, composed of guitarist Kim Thayil, bassist Hiro Yamamoto, and Chris Cornell on drums and vocals, recorded the demo in Jack Endino's basement four-track studio on April 24, 1985 for their friend Bruce Pavitt, hence the name of the tape, which features a rare early version of "Tears to Forget" sung by Yamamoto, and, as a bonus song, a Cornell's solo recording titled "The Storm".