In 1898 French chemists-physicists and husband-and-wife team Pierre (1859–1906) and Marie Curie (1867–1934) discovered radium, the first radioactive element, which proved to be an effective weapon against cancer. They conducted further experiments in radioactivity, a word that Marie Curie coined, distinguishing among alpha, beta, and gamma radiation. Upon Pierre’s death in 1906, Marie succeeded him as professor of physics at the Sorbonne. During World War I (1914–18), Curie organized radiological services for hospitals. From 1918 to 1934 she went on to become director of the research department of the Radium Institute of the University of Paris. The Curies’s daughter, Irène (1897–1956), followed in her parents’ footsteps, becoming a physicist, and marrying (in 1926) another scientist, Frédéric Joliot (1900–1958), who served as director of the Radium Institute for 10 years beginning in 1946. The pair, who were known as the Joliot-Curies, contributed to the discovery and development of nuclear reactors. The Curies and the Joliot-Curies were all Nobel laureates.