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21.
This paper compares the relative efficiencies of pollution taxes, pollution standards, and the auctioning of pollution rights when the marginal damage function or marginal control cost are subject to uncertainty. In the first case, we find that all instruments yield the same expected social surplus. In the latter case, the choice of the optimal instrument depends, in general, on the relative elasticities of the marginal damage and marginal expected cost functions, on the way in which uncertainty enters the model, and on the distribution of the error term. Policy conclusions are derived.  相似文献   
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精神分析批评作为一种文学批评方法,可以用于解释作者的创作动机和研究文学文本。简要梳理精神分析批评的理论渊源,分析其对文学研究的影响,指出其缺陷,旨在帮助文艺批评者更好、更有效地运用于文学批评。  相似文献   
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Campylobacter is a gram-negative, microaerophilic, curved rod and a normal resident of the gastrointestinal flora and may be the cause of disease in animals. Transmission to humans occurs by ingestion of contaminated food or by direct contact with infected animals. In the past few decades, an increasing number of reports have implicated the presence of this organism in human abortions as well. An infectious mechanism due to primary placental inflammatory damage followed by secondary damage to the fetus following placental insufficiency and ischemia was suggested. The most common species of Campylobacter are Campylobacter jejuni and Campylobacter coli, which are classically associated with enteritis in humans. We present a rare case of mid-gestation intrauterine growth restriction (IUGR) associated with maternal bacteremia caused by C. coli infection. Our literature review focuses on Campylobacter infections occurring in the second and third trimesters of pregnancy. In all cases, mild maternal symptoms consisting of fever and weakness were presented. However, associated adverse fetal outcome, including abortions, IUGR or preterm labor may occur more frequently than anticipated. Our report strengthens the importance of awareness to this finding and focuses the need to consume properly cooked meat during pregnancy. © 2015 John Wiley & Sons, Ltd.  相似文献   
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School buses contribute substantially to childhood air pollution exposures yet they are rarely quantified in epidemiology studies. This paper characterizes fine particulate matter (PM(2.5)) aboard school buses as part of a larger study examining the respiratory health impacts of emission-reducing retrofits.To assess onboard concentrations, continuous PM(2.5) data were collected during 85 trips aboard 43 school buses during normal driving routines, and aboard hybrid lead vehicles traveling in front of the monitored buses during 46 trips. Ordinary and partial least square regression models for PM(2.5) onboard buses were created with and without control for roadway concentrations, which were also modeled. Predictors examined included ambient PM(2.5) levels, ambient weather, and bus and route characteristics.Concentrations aboard school buses (21 mug/m(3)) were four and two-times higher than ambient and roadway levels, respectively. Differences in PM(2.5) levels between the buses and lead vehicles indicated an average of 7 mug/m(3) originating from the bus's own emission sources. While roadway concentrations were dominated by ambient PM(2.5), bus concentrations were influenced by bus age, diesel oxidative catalysts, and roadway concentrations. Cross validation confirmed the roadway models but the bus models were less robust.These results confirm that children are exposed to air pollution from the bus and other roadway traffic while riding school buses. In-cabin air pollution is higher than roadway concentrations and is likely influenced by bus characteristics.  相似文献   
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The diel periodicity of sex pheromone release was monitored in two mealybug species, Planococcus citri and Planococcus ficus (Hemiptera; Pseudococcidae), using sequential SPME/GCMS analysis. A maximal release of 2 ng/h pheromone by 9–12-day-old P. citri females occurred 1–2 h before the beginning of photophase. The highest release of pheromone by P. ficus females was 1–2 ng/2 h of 10–20-day-old females, approximately 2 h after the beginning of photophase. Mating resulted in termination of the pheromone release in both mealybug species. The temporal flight activity of the males was monitored in rearing chambers using pheromone baited delta traps. Males of both P. citri and P. ficus displayed the same flight pattern and began flying at 06:00 hours when the light was turned on, reaching a peak during the first and second hour of the photophase. Our results suggest that other biparental mealybug species display also diel periodicities of maximal pheromone release and response. Direct evaluation of the diel periodicity of the pheromone release by the automatic sequential analysis is convenient and will be very helpful in optimizing the airborne collection and identification of other unknown mealybug pheromones and to study the calling behavior of females. Considering this behavior pattern may help to develop more effective pheromone-based management strategies against mealybugs.  相似文献   
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The Kishon River, which is now an industrial sewage canal, may be turned into a recreational area in two stages, and by approximately 20 million dollar investment.

Stage A: The wastewater is treated in order to avoid polluted effluents from entering the river.

Stage B: The river water is treated in order to turn the river into a recreational area.  相似文献   
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Summary The major objective of the design of safe crowded transmitting antenna sites is not only to determine a safe zone around each individual antenna; rather, to establish safety areas at the antenna site itself, as well as, at the neighboring areas. The requirement is to ascertain the safety regions by considering the following parameters at each Test Point (TP) (or area segment): the contribution of N co-located radiating antennas to the total radiation incident at the TP, the radiation pattern of each antenna, the near/far field region of each antenna, and most importantly, the different Permissible Exposure Limits (PELs) associated with each operating frequency at the antenna site. Implementation of all the above-mentioned aspects in a suitable computer requires resources that only expert knowledgeable organizations possess. The graphically aided tool presented in this paper facilitates the calculation of a “safety zone” for RADHAZ around a crowded antenna site from the knowledge of the “safety ranges” which correspond to the individual transmitting antennas comprising it.  相似文献   
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