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91.
Posting or closing of swimming beaches because of faecal contamination is a widespread problem reported in many locations. In a risk-based approach to this problem, the risk to swimmers' health is assessed by field monitoring of indicator bacteria and the associated risks are managed by source controls and other remedial measures. In risk assessment, great advances have been made in recent years with the introduction of microbial source tracking (MST) techniques. Two such techniques, antibiotic resistance analysis and DNA fingerprinting, were applied in a study of causes of faecal contamination at two lake beaches in Toronto, Ontario. Both methods identified bird faeces as the dominant sources of E. coli. Coping with this type of pollution presents a major environmental challenge. 相似文献
92.
Weak or non-existent institutions are often cited as a major constraint facing management of many lake basins in Africa. By their nature lake basins cut across many sectoral and jurisdictional interests and therefore it is always the case that management of the basins is affected by actions within the various sectors and jurisdictions. Because of the complex nature of issues within lake basins, authority over management of lake basins is dispersed among several institutions, with no single institution having overall authority. Under these circumstances, a major challenge in lake basin management is how to ensure effective coordination among the various players. This paper reviews the situation of lake basin management at eight African lake basins and draws important lessons about lake basin management institutions. It is noted that fragmented approaches, lack of coordination across sectors, and lack of monitoring and enforcement are major institutional weaknesses. Also, it is observed that political will and commitment are essential for the management of African lake basins. 相似文献
93.
Freshwater drum (Aplodinotus grunniens) may be a predator of the invasive zebra mussel (Dreissena polymorpha), which established in Lake Winnipeg in 2013. In this study, the diets, trophic position, and growth of 51 freshwater drum collected in 2019 (six years post-zebra mussel invasion) were compared to 64 freshwater drum sampled in 2000. Benthic insect larvae were the dominant food items in both years. Although mollusks occur in high densities in Lake Winnipeg, they were only consumed by a few freshwater drum in either sample year. Zebra mussels were not a frequent prey item in 2019 as they were only consumed by four of the sampled freshwater drum. Stable isotope analysis of white muscle tissue yielded similar δ13C and δ15N values in both years and were consistent with a benthic, insectivorous diet. Length-at-age data derived from otoliths revealed that the 2019 population had at least an equal growth rate to the 2000 population. Weight-at-length data suggested that fish condition was greater in 2019 than in 2000, which coincided with increased benthic macroinvertebrate density in Lake Winnipeg. Based on these findings, Lake Winnipeg freshwater drum continue to feed predominantly on insect larvae and not zebra mussels. 相似文献
94.
Klimova T. G. Nikolaeva O. O. 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2021,55(2):296-304
Power Technology and Engineering - Anecessary requirement for automatic excitation regulation systems is ensuring the stability of the electric energy systems (EES) and the required quality of the... 相似文献
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Three years after launching the team-based Quality For All program, Top Chemical Company CEO Sam Verde was searching for a team-based compensation system that would reflect his company's new philosophy. With a committee gathered to discuss the issue, Verde confronts the fact that changing pay plans is an issue few people can agree on. "Very simply," explains vice president for compensation Gilbert Porterfield, "the plan is designed to give employees working on teams real incentives for constant improvement and overall excellence. The variable aspect of the system pays employees for the performance of their group." This doesn't sit well with the others. "It's going to punish teams like mine for the failings of others instead of rewarding us for the work we do and have already done," says packaging team representative Ruth Gibson. Another committee member feels that team-based anything is a "motivational happy land that doesn't square with how people really work." While Verde likes the proposed pay plan, he has doubts over whether his employees will accept the risk. Upper management has no problem basing 60% of its pay on TopChem's performance. But getting line employees to risk part of their salaries--even as little as 4%--on the ups and downs of the chemical industry may be more trouble than it's worth. Four experts on compensation reveal where Top Chemical went wrong in its plan and how Sam Verde might bring about change successfully. 相似文献
98.
Mahnke JT 《Medical economics》1992,69(3):84, 86, 89 passim
99.
Dennen T 《Risk management (New York, N.Y.)》1992,39(9):71-2, 74, 76
In summary, there are costs to maintaining separate systems to cover both work- and non-work-related injuries and illnesses; there are also significant costs associated with achieving coordination--if not integration--of the two plans. Overall, the financial data do not indicate that the overlap between workers' compensation and health benefits is of such magnitude as to justify integration regardless of cost; however, the data do suggest that judicious exploitation of opportunities to coordinate the two programs, especially in regard to managing health care providers, may generate significant savings. 相似文献
100.