Design of organizational guidelines and procedures for the implementation of a community advisory committee for the Boys Town vocational career center

The purpose of this study is to design organizational guidelines and procedures for the implementation of a community advisory committee for the Boys Town Vocational Career Center

Nucleosynthesis and Clump Formation in a Core Collapse Supernova

High-resolution two-dimensional simulations were performed for the first five minutes of the evolution of a core collapse supernova explosion in a 15 solar mass blue supergiant progenitor. The computations start shortly after bounce and include neutrino-matter interactions by using a light-bulb approximation for the neutrinos, and a treatment of the nucleosynthesis due to explosive silicon and oxygen burning. We find that newly formed iron-group elements are distributed throughout the inner half of the helium core by Rayleigh-Taylor instabilities at the Ni+Si/O and C+O/He interfaces, seeded by convective overturn during the early stages of the explosion. Fast moving nickel mushrooms with velocities up to about 4000 km/s are observed. This offers a natural explanation for the mixing required in light curve and spectral synthesis studies of Type Ib explosions. A continuation of the calculations to later times, however, indicates that the iron velocities observed in SN 1987 A cannot be reproduced because of a strong deceleration of the clumps in the dense shell left behind by the shock at the He/H interface.Comment: 8 pages, LaTeX, 2 postscript figures, 2 gif figures, shortened and slightly revised text and references, accepted by ApJ Letter

Determining the fate and toxicity of polycyclic aromatic hydrocarbons associated with coal-tar and other carbonaceous material particles in urban lakes

U.S. Department of the InteriorU.S. Geological SurveyOpe

Effect of soil on the mutagenic properties of waste water

The disposal of complex mixtures such as waste water on agricultural lands poses known and unknown environmental risks. Mutagens may be introduced into the eco-system and perhaps concentrated by crop plants or leached into ground water supplies. The purpose of this study was to determine the biological effect of a mutagenic waste water before and after application to soil. We used an XAD-8 methanol extract of waste water from the municipal sewage treatment facility at Sauget IL. This extract was a potent direct acting mutagen when assayed with the Salmonella typhimurium. 1 and 3 ml of extract were brought up to 10 ml volumes with water and added to 10 a of sterile or nonsterile , native clay loam. These mixtures were placed in a shaking water bath at room temperature for 0, 24, and 48 h. After separation of solid and liquid portions by filtration, dichloromethane was added to extract the organic fractions from each component. Solvent extractions were evaporated to dryness under vacuum and brought up in DMSO. Tests for mutagenic activity were conducted using strain TA98. After addition to the soil for greater periods of time the mutagenic activity decreased. The solid component exhibited greater mutagenic activity than the liquid. The XAD-8 extract was also assayed using the yg2 assay in Zea mays and the micronucleus assay in Tradescantia. The extract did not induce mutation or chromosome aberrations in these assays. The sludge from the Sauqet plant was chemically fractionated and assayed with S. typhimurium strains TA98 and TA100. The neutral fraction was the most mutagenic fraction followed by the weak acid,-strong acid and basic fractions. These chemical fractions uncovered more mutagenic potency than was predicted by assaying a crude organic extract of the sludge.U.S. Department of the InteriorU.S. Geological SurveyOpe