Occupational exposure to high levels of respirable quartz can result in respiratory and other diseases in humans. The Mine Safety and Health Adminstration (MSHA) regulates exposure to respirable quartz in coal mines indirectly through reductions in the respirable coal mine dust exposure limit based on the content of quartz in the airborne respirable dust. This reduction is implemented when the ...

Quartz fibers are used in high energy physics experiments as the active medium in high radiation area calorimetry. Quartz fibers are also used in the transmission of optical signals. Even though quartz does not damage by moderate amounts of irradiation, the clad of the fibers and the protective coating (buffer) do damage reducing light transmission. Various types of quartz fibers have been irra...

This paper describes a new generation of cryptosystems, Hidden Field Equations, focusing on its application of creating short digital signatures with fast verification times, using parameters recommended in Quartz specification. Besides theoretical information, numerical examples, implementation details and speed comparisons with other generally used signature schemes are also provided.

In this study we have measured exposure levels to quartz in different parts of the slate industry in Alta, Northern Norway. Full shift personal samples were collected from the breathing zones of outdoor and indoor workers in the slate quarries and a slate factory. The quartz content of respirable dust was between 7 and 41%. The slate factory had the lower quartz levels although 41% of total and...

Fracturing quartz produces silica-based radicals on the fracture planes and generates hydroxyl radicals (.OH) in aqueous media. .OH production has been shown to be directly associated with quartz-induced cell damage and phagocyte activation in vitro. This .OH production in vitro is inhibited by desferrioxamine mesylate, an Fe chelator, indicating involvement of a Fenton-like reaction. Our objec...

this research was conducted from july 1993 to june 1994 on the total population (711 workers) of a glass factory. the purpose of this study was to determine the quantitative free silica (quartz) in respiratory zone of workers in glass industry. field samples including 50 samples total dust and 37 samples respirable dust and standard simplex were collected on membrane filters using skc dust samp...

Interleukin-10 (IL-10) can downregulate expression of several proinflammatory cytokines including chemokines. This study investigated the role of IL-10 in the acute response of the rat lung to quartz particles. Intratracheal instillation of rats with 1 mg of quartz produced an inflammatory and cytotoxic response demonstrated by increased bronchoalveolar lavage (BAL) fluid neutrophils, lactate d...