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Substantial conflict exists over water management and allocation in the Platte River Basin of Nebraska. An interdisciplinary computer simulation model, representing the water quantity, water quality, environmental, and economic dimensions of the conflict, was developed in order to analyze the tradeoffs among allocation scenarios. Most importantly, decisionmakers and interest groups were involved in model development. Simulation results for a base case and two scenarios are presented. One scenario favors protection of instream flow for wildlife; the other favors water diversions for agriculture. Impacts of the instream flow scenario, as measured by the amount of land irrigated, groundwater levels, the amount of wildlife habitat for cranes and catfish, and net agricultural benefits did not differ greatly from those of the base case. However, impacts of the diversion scenario were substantial. On the negative side, instream flows and wildlife habitat declined an average of 39 percent; while, on the positive side, groundwater levels and net agricultural benefits each increased 6 percent. The modeling process was successful insofar as it promoted an understanding among the highly diverse interest groups of the systems nature of the Basin. One agreement on a water diversion schedule among three of the parties has been reached, partly as a result of this process. More comprehensive compromises have not yet been forged. Our experience, however, indicates that modeling success at the policymaking level depends more on the extent to which the policymakers understand the model than it does on model sophistication.  相似文献   
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ABSTRACT: Public information, an important contributer to citizen involvement in the governmental decision making process, has traditionally been given a low priority by government agencies. However, citizens are becoming increasingly concerned about governmental decisions that affect their lives and are demanding more information about governmental activities, including information about water resource issues, Because of this active citizen interest and involvement, the role of public information in increasing citizen awareness is becoming more important. Government officials and professionals should recognize that public information efforts also play an important role in achieving increased credibility and respect for their agencies. Once an agency recognizes the importance of public information and decides to initiate a public information program, careful planning is required to develop a program that addresses the needs of both the citizens and the agency. Two of the most flexible and cost effective ways to get information to the publié are through publications and public meetings. Both can be easily adapted to suit the needs of specific audiences and projects. A successful public information program can be carried out at a relatively low cost, but it requires a substantial amount of time and energy. The commitment of time and energy for this purpose is a good investment, however, because an effective public information program can play a significant role in improving the quality of governmental decisions through the increased involvement of the citizenry.  相似文献   
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ABSTRACT: Effects of no-flow river conditions on the quantity and quality of water in the Platte River well field of the City of Grand Island, Nebraska, were examined utilizing a finite-difference computer simulation model specifically developed for this well field. Results suggest that the effects of these no-flow periods on water quality may be most important. In particular, the no-flow periods eliminate the hydraulic barrier between the well field and an area north of the River that is contaminated with nitrate (concentrations in the 20 to 40 mg/1 NO3-N range). They also change the direction and velocity of movement of the contaminated ground water. Simulation results indicate that contaminated ground water moves toward the well field with a velocity of 0.42 ft/d after 30 days of no-flow and 1.43 ft/d after 180 days of no-flow. Limiting no-flow conditions to 10 consecutive days would protect the well field.  相似文献   
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The specialty of fetal surgery or fetal intervention is one of the most exciting emerging fields of modern medicine. It is made possible by decades of major developments in antenatal imaging, obstetric anaesthesia, fetal medicine, paediatric surgery, and of course by the bold and novel practitioners willing to take new steps to advance the field. Beginning in the 1970s, it has now reached a stage of maturity where there are several established in utero procedures and countless clinical trials and studies to develop more. But what is the legal situation that fetal surgeons find themselves in? What are the rights and legal protections for the fetus and the mother, both of which are arguably the patient? This article will address this question, discussing and summarising the current legal frameworks governing fetal surgery in the jurisdictions of the United Kingdom, European Court of Human Rights, and the United States of America as well as discuss what the future may hold and how researchers and physicians in the specialty can best navigate the legal environment.  相似文献   
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The environmental and economic components of a region or a nation are inextricably linked. Moreover, environmental protection technology must deal specifically with the linkages between the economy and the environment—that is, with by-products of the economy as they move from the economy to the environment or with natural resources as they move from the environment to the economy. Yet, environmental policy analyses are rarely able to focus on these linkages. A conceptual framework aimed at mitigating that inadequacy is developed here. The framework is tied to its theoretical basis in thermodynamics and is utilized to identify generic categories of environmental protection strategies, to identify some disadvantages of current strategies, and to suggest alternatives.  相似文献   
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