Marie Curie theory of "radioactivity" (a term that she coined), techniques for isolating radioactive isotopes, and the discovery of two elements, polonium and radium. Under her direction, the world's first studies into the treatment of neoplasms were conducted using radioactive isotopes. She founded the Curie Institutes in Paris and in Warsaw, which remain major centres of medical research today. During World War I, she developed mobile radiography units to provide X-ray services to field hospitals. While a French citizen, Marie Skłodowska Curie, who used both surnames, never lost her sense of Polish identity. She taught her daughters the Polish language and took
Marie Curie of radioactivity, is named in honour of her and Pierre Curie (although the commission which agreed on the name never clearly stated whether the standard was named after Pierre, Marie or both of them). The element with atomic number 96 was named curium. Three radioactive minerals are also named after the Curies: curite, sklodowskite, and cuprosklodowskite. She received numerous honorary degrees from universities across the world. The Marie Skłodowska-Curie Actions fellowship program of the European Union for young scientists wishing to work in a foreign country is named after her. In Poland, she had received honorary doctorates from the Lwów