(2or PERCENTHGE LIFE SPHN SHORTENING PERCENTAGE LIFE SPAN SHORTENING X- RAND GRMMA-RAYS PURATION-OF-LIFE €XPOSURE MICE <MALE + FEMALE > \aay wa ——- aa ais ca 7 as 7 a u 8 i5aa + qaua US7e4 DOSE <RAD> b Bua ¢ 7522 Figure XI. Best fit to the low-LET radtation data in Figure X. The numbers in the body of the graph are the dose rates (rad/day) at which the doses specified in the abscissa are cumulated during the entire life of the animals.