A laser apparatus wherein a gain medium and an optical output assembly are mounted on a common, thermally conductive substrate which provides selective thermal control of the gain medium and output components on the substrate while avoiding unnecessary thermal control of other laser components, and methods for selectively cooling a gain medium and output components of a laser apparatus. The plurality of network electronic devices includes electronic devices, each of which is capable of providing at least one service. The neutrons produce fission products in the special nuclear material which generate gamma rays. The incident energy rebounds from the structure as scattered energy, at least a portion of which propagates toward the energy detector. The threaded portion of the second fastening member is screwed into the threaded hole of the insertion member.