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11.
Exposure of small laboratory animals to power-frequency high-voltage electric fields was reported to have endocrinological effects, including changes in pineal melatonin levels. It has been assumed that these results are directly attributable to electric-field effects, but this article suggests that air ionization, produced by corona activity at the animals’ body surfaces, may have been biologically active and could be relevant to the interpretation of some epidemiological and other studies. Although presently a matter of dispute, there is evidence that atmospheric ionization may be biologically active and could provide an alternative explanation for at least some apparent electromagnetic field interactions with biological subjects. Consideration of the electricity utilization environment as a whole, rather than one selected component, could allow the introduction of lower-cost, precautionary and putative hazard remediation measures.  相似文献   
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Jamaica has developed a new strategy designed to allow it to expand its bauxite and alumina production, to diversify both its markets and its sources of investment and, to move downstream into the production of aluminium and semi-finished products. Some benefits of this new strategy are already evident, several bauxite mines are being expanded, alumina plants are being re-opened while others are adding additional capacity, and the countries of Europe, Asia and North America are showing renewed interest in investing in Jamaica. With its new strategy, Jamaica intends to participate more fully in the world economy.  相似文献   
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Introduction and large-scale production of synthetic halogenated organic chemicals over the last fifty years has resulted in a group of contaminants that tend to persist in the environment and resist both biotic and abiotic degradation. The low solubility of these types of contaminants, along with their toxicity and tendency to accumulate in food chains, make them particularly relevant targets for remediation activities. Among the mechanisms that result in dehalogenation of some classes of organic contaminants are stimulation of metabolic sequences through introduction of electron donor and acceptor combinations; addition of nutrients to meet the needs of dehalogenating microorganisms; possible use of engineered microorganisms; and use of enzyme systems capable of catalyzing reductive dehalogenation. The current state of research and development in the area of reductive dehalogenation is discussed along with possible technological application of relevant processes and mechanisms to remediation of soil and groundwater contaminated with chlorinated organics. In addition, an overview of research needs is suggested, which might be of interest for development of in-situ systems to reduce the mass of halogenated organic contaminants in soil and groundwater.  相似文献   
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Salmon farming is a rapidly expanding industry. In order for it to develop in an ethical manner, many ethical issues must be confronted. Among these are questions regarding the quality of life of salmon on farms. To develop reasonable answers to these questions considerable thought must be devoted to developing appropriate standards of care for salmon. If these questions are not addressed the results could be bad both for salmon and for salmon farmers.  相似文献   
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The Supreme Court's interpretation of the commerce clause controls the balance of power between state and federal governments in the United States. An understanding of the relationship between the different government levels is essential for resource managers concerned with resource and environmental issues. This study examines selected Supreme Court decisions between 1976 and 1988 to answer three questions raised by the commerce clause: (1) Is the regulated item an article of commerce? (2) Do state laws burden interstate commerce? (3) Is federal commerce regulation limited? The balance of power among the justices and the commerce clause theories affecting the federal role in resource management are also examined. Since ratification of the Constitution, the Supreme Court has continuously increased federal power, but states have power to act independently as long as contradictory federal laws do not exist and state law does not impermissively affect commerce. If Congress regulates an individual's use of resources, their power is unquestioned. Future Court decisions will not significantly reduce the federal role in resource management even if the Court's membership changes. Even the supporters of states' rights on the Court realize increased federal power is a necessary part of the country's evolution. The purpose of the commerce clause is to create a national economic unit with free location principles. The Court supports this purpose today and will in the future.  相似文献   
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According to a rights view it is acceptable to kill animals if they are innocent threats or shields or are in a lifeboat situation. However, according to advocates of such a view, our practices of killing animals for food or scientific research may be morally unacceptable. In this paper we argue that, even if we grant the basic assumptions of a rights view, a good deal of killing of animals for food and scientific research continues to be morally acceptable.  相似文献   
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尽管继续有科学不确定性,但表明当前捕捞实践不可持续的证据与日俱增.在国家层次和国际层次上,人们越来越认真地对待关于过度捕捞及其对穷国食品保障的潜在威胁的告诫.近年来已经看到了一波改善渔业管理的协议.然而,无论在当地社区和传统可能处于危急之中的富国,还是在鱼类对于食品供应也具有根本重要性而且捕捞是沿海地区少数几种生活来源之一的穷国,对减少世界捕捞船队的规模都有强大阻力.  相似文献   
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