Stimulated emission of particles by 1+1 dimensional black holes

The stimulated emission of massless bosons by a relativistic and the CGHS black hole are studied for real and complex scalar fields. The radiations induced by one-particle and thermal states are considered and their thermal properties investigated near the horizon. These exhibit both thermal and non-thermal properties for the two black-hole models.Comment: 29 pages, Latex (run 3 times

Survival of Fecal Contamination Indicator Organisms in Soil

Soils amended with human or animal waste may result in pathogen contamination of ground and surface water. Because temperature has been shown to affect pathogen survival, two laboratory studies were conducted to evaluate the impact of extremes in temperature on bacterial and viral pathogen indicator die-off in soil. A Captina silt loam was amended with broiler litter (0.1 g/g dry soil), septic tank effluent, or Escherichia coli (ATCC 13706) culture (both at 0.04 and 0.1 mL/g dry soil in the two respective studies), incubated at 5 and 35°C, and analyzed over time to determine the number of fecal coliform, E. coli, and coliphage remaining. Pathogen indicator die-off rate constants (k) for all indicator- temperature-treatment combinations were determined by first-order kinetics. For all three pathogen indicators, die-off was significantly more rapid at 35°C than at 5°C. In both studies, fecal coliform die-off rates were not different from E. coli die-off rates across each temperature-treatment combination. Levels of these bacterial indicators appeared in a ratio of 1:0.94 with 95% confidence intervals at 0.89 and 0.99 in the E. coli- and litter-amended soils. Die-off of the viral indicator was significantly slower than the die-off of the bacterial indicators at 5°C in litter-amended soil. Die-off of the bacterial indicator, E. coli, in soil amended with E. coli culture was not significantly different than die-off in soil amended with broiler litter at 5 or 35°C in the two studies. Because the higher incubation temperature increased die-off rates for all three indicators, it is expected that the potential for contamination of ground and surface water decreases with increasing temperature

Continuation of Illinois River Water Quality Monitoring of Moores Creek

In Northwest Arkansas, nutrients transported by surface water are a major concern. These nutrients are implicated in causing water quality impairment of lakes in Northwest Arkansas and eastern Oklahoma. The nutrients of concern are nitrogen and phosphorus. Nitrogen and phosphorus stimulate algae production in water bodies and can cause objectionable water quality. Problems associated with algae growth are aesthetic impairment, objectionable taste and odor of potable water, interference with recreation activities, and fish kills in some hyper-eutrophic cases. The sources of these nutrients are primarily from land application of confined animal wastes as soil amendments to pastures. In 1990, the University of Arkansas, Fayetteville Cooperative Extension Service (CES) and U. S. Department of Agriculture Natural Resources Conservation Service (NRCS) initiated a program in the Muddy Fork watershed of the Illinois River. This program focused on implementing best management practices (BMP) in the watershed that would reduce nutrient losses from pastures. Education, technical assistance, and cost sharing was the approach used by these agencies to encourage BMP implementation. The predominant BMPs implemented were nutrient management, pasture and hay-land management, waste utilization, dead poultry compo sting, and waste storage structures. In 1991, the Arkansas Soil and Water Conservation Commission (ASWCC) and the U. S. Environmental Protection Agency (EPA) sponsored a monitoring project in the Lincoln Lake Basin. The Lincoln Lake Basin, part of the Muddy Fork watershed, received appreciable BMP implementation by the CES and NRCS. The objective of this monitoring project was to demonstrate the effectiveness of the implemented BMPs in reducing nutrient transport from the pastures in this intensively managed area. Nutrient transport by Moores Creek and Beatty Branch, the two streams that feed Lincoln Lake, was monitored from September 1991 until April 1994 (Edwards et al., 1996 and 1997). During storm flow conditions, significant decreases in mean concentrations and mass transport of nitrate-nitrogen (NO3-N), ammonia-nitrogen (NH3- N), total Kjeldahl nitrogen (TKN), and chemical oxygen demand (COD) were observed in this watershed and attributed to BMP implementation. There were no decreases in total phosphorus (TP) or total suspended solids (TSS). Likewise, during base flow conditions, significant decreases of NH3-N, TKN, and COD were observed. After the end of this initial monitoring project, the stream monitoring continued on a limited basis in the Lincoln Lake basin. This report will compare the results of continued monitoring to the findings of the first project. This supplemental monitoring was conducted from 1 January 1995 until 30 September 1997

Extended Water Quality Monitoring of the Lincoln Lake Watershed

For seven years, the Lincoln Lake (Moores Creek and Beatty Branch) watershed was monitored for improvements in water quality resulting from agricultural best management practices (BMP) implemented to reduce nutrient transport. During the first three years of monitoring (1991 to 1994), nitrogen transport declined significantly (Edwards et al., 1994, 1996, and 1997) under both base and storm flow conditions. This decline in nitrogen transport was again observed in the three-year period following 1994 (Vendrell et al. 1998). This monitoring effort has demonstrated that water quality bas improved in the Lincoln Lake watershed. However, since the nitrogen transport continued to decline and there was some indication that phosphorus may begin to decline, monitoring was extended for another year (1998)