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On the cover: A research team led by PrincetonUniversity is using the ALCF's Theta supercomputer to perform large-scale 3D simulations aimed at determining the mechanism of core-collapse supernova explosions. Depicted is the neutrino-driven roiling convection of the nuclear material behind the newly reenergized supernova shock wave that surrounds the newly birthed neutron star, just hundreds of milliseconds after shock revival. The isosurfaces are of specific entropy and the coloring follows the electron fraction. The pathlines trace infalling parcels of matter caught up in the turbulence of the explosion. The neutrino-heated turbulent bubbles help drive the supernova explosion shock wave outwards.

The requirements for lighting for draughtsmen were studied by a survey in ten different offices by questionnaire and interview. Independently, physical and subjective appraisals of the lighting and visual environments were carried out and the results were compared with the draughtsmen's reactions. From their reactions to the different kinds of lighting experienced, recommendations have been deduced for both daylighting and artificial lighting to achieve the most satisfactory conditions. For offices with a depth to accommodate more than four boards, or without double side daylighting, some top lighting in daytime is generally advisable. At night satisfactory conditions are most easily obtained by a moderately high level of general lighting of comfortable quality, supplemented by local lighting on the boards. If these latter are to be dispensed with, special attention to the shadowless quality of the lighting, brightness distribution in the environment, and elimination of reflected glare, is essential.