 Bradbury took charge at Los Alamos at a difficult time . Staff were leaving in droves , living conditions were poor and there was a possibility that the laboratory would close . He managed to persuade enough staff to stay , and got the University of California to renew the contract to manage the laboratory . He pushed continued development of nuclear weapons , transforming them from laboratory devices to production models . Numerous improvements made them safer , more reliable and easier to store and handle , and made more efficient use of scarce fissionable materiel . 
