Nobel Prize relevant fields was greater), a greater delay in awarding Nobel Prizes for women's achievements making longevity a more important factor for women (Nobel Prizes are not awarded posthumously), and a tendency to omit women from jointly awarded Nobel Prizes. Four people have received two Nobel Prizes. Marie Curie received the Physics Prize in 1903 for her work on radioactivity and the Chemistry Prize in 1911 for the isolation of pure radium, making her the only person to be awarded a Nobel Prize in two different sciences. Linus Pauling was awarded the 1954 Chemistry Prize for his research into the chemical
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