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Pierre Weiss
French physicist who investigated magnetism and determined the Weiss magneton unit of magnetic moment. Weiss's chief work was on ferromagnetism. Hypothesizing a molecular magnetic field acting on individual atomic magnetic moments, he was able to construct mathematical descriptions of ferromagnetic behaviour, including an explanation of such magnetocaloric phenomena as the Curie point. His theory succeeded also in predicting a discontinuity in the specific heat of a ferromagnetic substance at the Curie point and suggested that spontaneous magnetization could occur in such materials; the latter phenomenon was later found to occur in very small regions known as Weiss domains. His major published work was Le magnetisme ( 1926).

Robert C. Gallo
American scientist who co-discovered (1984) the virus responsible for AIDS - human immunodeficiency virus (HIV). The French scientist Luc Montagnier independently found the same virus in 1983, but did link it with AIDS. Gallo developed the HIV blood test. Then health care workers could for the first time screen for the AIDS virus, both to protect blood transfusion stocks, and also to permit faster diagnosis of patients. Gallo continued to research therapies for those infected with HIV. In 1996, he discovered a natural compound - chemokines - can block the HIV virus and arrest the progression of AIDS. After 30 years at the National Cancer Institute, in 1996 he became head of the new Institute of Virology.