The purpose of this study was to quantify the ultraviolet B (UVB) output and in vitro previtamin D(3) synthesis over time from various artificial light sources. Three incandescent lamps, T-Rex Active UVHeat 160 watt spot, T-Rex Active UVHeat 160 watt flood, and ZooMed PowerSun 160 watt flood, and two 1.2 m fluorescent lamps, Sylvania Blacklight 350 BL and ZooMed Reptisun 5.0, were studied. Tota...

This paper explores the physical mechanisms responsible for experimental observations that led to the definition of ‘‘photo-induced hydrogen outgassing of glass’’. Doped borosilicate glass samples were placed inside an evacuated silica tube and heated in a furnace or by an incandescent lamp. It was observed that hydrogen release from the glass sample was faster and stronger when heated by an in...

The purpose of this study was to determine if there was an objective difference in reading between four commonly available lamps, of varying spectral radiance, for 13 subjects with age-related maculopathy (ARM) or non-exudative age-related macular degeneration (AMD)--logMAR visual acuity between 0.04 and 0.68. At a constant illuminance of 2000 lux, there was no interaction between ARM and AMD s...

The use of carbon and tungsten filaments mounted in vacuum as early incandescent lamps is well-known, but it is less often realised that an early competitor was Nernst’s ceramic lamp. This made use of the property that , although good insulators at room temperature, many oxides become partially conductive when strongly heated. This is due to the migration of ions rather than electrons, and was ...

INTRODUCTION Accident data for 2003-2007 indicate that slip, trip, and falls (STFs) are the second leading accident class (17.8%, n=2,441) of lost-time injuries in underground mining. Proper lighting plays a critical role in enabling miners to detect STF hazards in this environment. Often, the only lighting available to the miner is from a cap lamp worn on the miner's helmet. The focus of this ...

Many techniques exist to measure airborne volatile organic compounds (VOCs), each with differing advantages; sorbent sampling is compact, versatile, has good sample stability, and is the preferred technique for collecting VOCs for hygienists. Development of a desorption technique that allows multiple analyses per sample (similar to chemical desorption) with enhanced sensitivity (similar to ther...