Chien-Shiung Wu
World War II brought some new opportunities. The Office of Scientific Research and Development, under Vannevar Bush, began in 1941 to keep a registry of men and women trained in the sciences. Because there was a shortage of workers, some women were able to work in jobs they might not otherwise have accessed. Many women worked on the Manhattan Project or on scientific projects for the United States military services. Women who worked on the Manhattan Project included Leona Woods Marshall, Katharine Way, and Chien-Shiung Wu. It was actually Wu who confirmed Enrico Fermi's hypothesis through her earlier draft that Xe-135 impeded the B reactor from working. The adjustments made would quickly let the project resume its course.