The body of a missing nuclear lab worker has been found — alongside a gun — almost a year after she vanished without a trace, the latest in a string of disappearances and bizarre deaths involving experts and government employees working at some of the most secretive US national security facilities. The remains of Melissa Casias, 54, who worked at the Los Alamos National Laboratory in New Mexico, were found in Carson National Forest over the weekend, some six miles from where she was last seen