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221.
The importance of improving the effectiveness of Plan EIA and SEA-type evaluations in China cannot be overstated: at a time when the country's economy is being boosted by a stimulus package worth over RMB 400 trillion – largely for infrastructure – the pressure on China's already strained environment and resource base is bound to increase. The aim is to propose the criteria for plan EIA's effectiveness to raise the awareness of the need to strengthen the performance of the assessment and maximize its potential benefits. The authors first review critically the discourse on the effectiveness of the impact assessment, identifying three dimensions: substantive, procedural and incremental. The resulting conceptual framework allows them to interpret the weaknesses of the Chinese discourse on the effectiveness and of the practice of the Plan EIA to date. The result is the identification of a clear gap, both in terms of the breadth of the concept, and in terms of the quality of the existing criteria, which tend to be very generic to the point of inapplicability. The analysis also reveals a need for transitioning from formal models of the Plan EIA to more strategic approaches, in a gradual manner that is consistent with context-specificities. The proposal of a set of preliminary criteria for effectiveness is therefore structured on three levels. This framework is meant to input into the ongoing debate on how to improve the practice of PEIA and the SEA-type evaluations in China, and provide ideas for a government strategy aimed at maximizing the positive impact of PEIAs on planning, as well as on the context of application.  相似文献   
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A case of dilated coronary sinus with persistent left superior vena cava diagnosed at 33 weeks in a fetus with trisomy 18 is reported. The features of this cardiac anomaly on prenatal ultrasonography and its association with trisomy 18 are discussed. Published in 2003 John Wiley & Sons, Ltd.  相似文献   
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This paper reviews the possible future situation of the Rhone River in the Swiss part of its catchment. Physical processes in the Alps govern the behaviour of the Rhone from its source (Rhone Glacier) to the Lake of Geneva, and substantial changes are expected to occur in the amount and seasonality of precipitation, and in the response of snow and glaciers to a warming climate. As a result, discharge in the alpine part of the Rhone River is likely to undergo an increase in winter and early spring, but strongly decreases from late spring to late autumn. These changes in water regimes will certainly be accompanied by more frequent geomorphic hazards, related to increases in heavy precipitation events and the melting of permanently frozen grounds. The direct and indirect impacts of a warming climate will affect key economic sectors such as tourism, hydropower, and agriculture, while shifts in extreme events will have an impact on the vulnerability of infrastructure and a range of economic sectors and services. Projections of the future course of events can help in advance planning and decision making in order to alleviate some of the more negative consequences of climate and hydrological impacts on key economic sectors in the region. This paper will thus discuss issues related to current and future water governance in the region, whether water-related policies are sufficiently robust today to cope with what may be rapid changes in water availability and water use in coming decades, and to resolve possible rivalries between economic sectors that may be increasingly confronted with problems of water availability at critical times of the year.  相似文献   
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A simple and dynamic pharmacokinetic model was developed to predict bioconcentration of organic contaminants in earthworms. The model was parameterized experimentally by placing Lumbricus terrestris in soil contaminated with 200 μg/cm2 of malathion. The toxicokinetics of malathion uptake, depuration, and degradation in soil is measured. After parameterization, the model was able to accurately predict the bioconcentration factor of malathion at steady state. Sensitivity analyses were performed and the rate of absorption was determined to be the most sensitive parameter. Varying the rate of malathion elimination from earthworm tissues, malathion degradation, and the amount of malathion applied to the soil by 25-fold did not result in the bioconcentration of malathion. An increase in the rate of malathion absorption into earthworm tissues by 25-fold did result in bioconcentration. Previously published pharmacokinetic studies on xenobiotics with log K ow values ranging up to 8.05 were used to test the predictive capacity of the model. The model was able to predict from 83% to 105% of the experimentally derived bioconcentration factors.  相似文献   
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We investigated relationships among North Atlantic Tigriopus brevicornis populations and their relationships to Mediterranean T. fulvus and North American T. californicus, using crossing experiments and mitochondrial DNA sequencing. All T. brevicornis populations tested were interfertile, while interspecific crosses produced either no offspring or offspring that did not survive past the larval stage, with the exception of a few T. brevicornis × T. californicus crosses that produced mature adults. DNA sequencing of a fragment of mitochondrial cytochrome oxidase I (COI) showed that samples of T. brevicornis from Iceland, the Faroes, Ireland, Scotland and Nova Scotia formed a single shallow clade. In contrast, T. brevicornis from more southern populations in France and Portugal formed a clade with substantially greater branch lengths. Tigriopus brevicornis was monophyletic, and T. brevicornis plus Mediterranean T. fulvus were together also monophyletic. The phylogeography of T. brevicornis closely mirrored that found in T. californicus, with substantially reduced interpopulation divergence at northern latitudes. The known distribution of T. brevicornis in Iceland and the Faroes is shown and dispersal mechanisms and habitat selection briefly discussed.  相似文献   
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Biodegradation experiments of various polycyclic aromatic hydrocarbons were studied with mixed bacteria culture under aerobic conditions. An easy‐to‐handle clean‐up procedure was developed for PAH and their metabolites simultaneously as well as a gc‐ms‐method to identify and quantify these compounds.

Anthracene and dibenzothiophene are completely degradable in an aqeous system, whereas biodegradation of benzo(k)fluoranthene and benzo(h)quinoline is possible only in an oil‐in‐water‐system with dodecane as cosubstrate. No degradation of nitronaphthalene was observed in aqueous systems. New metabolites are 2,3‐dihydroxybenzothiophene, hydroxybenzothiophenecarbonic acid and benzothiophenequinone for dibenzothiophene and hydroxyfluoranthenic acid for benzo(k)flouranthene. Whereas the former metabolites are degradable under the experimental conditions, the latter accumulates during the degradation experiment.

The results are important for microbiological wastewater treatment, since knowledge of biodegradation processes is indespensable for the successful treatment of PAH‐containing wastewater.  相似文献   
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