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551.
In this study, the distribution of airborne manganese (Mn) bound with particulate matters (PM) was investigated using data sets collected from 15 major cities in Korea over a 16-year time span (1991–2006). The mean Mn concentration measured from all the major cities in Korea throughout the entire study period was 71 ng m?3, while the annual mean values of different cities ranged from 10.5 ng m?3 in Yeosu (2003) to 615 ng m?3 in Wonju (2006). The Mn levels were considerably larger in industrialized areas than in other land-use types. The Mn concentrations in the major industrial cities of Pohang, Incheon, and Ansan averaged 255, 98.2, and 84.6 ng m?3, respectively; these values were far higher than those measured typically at most cities, e.g., 20–60 ng m?3. Seasonal patterns characterized by the peak occurrence in spring and the noticeable drop in summer reflected the effects of the massive PM inflow from China (spring) and effective washout by summer monsoon in East Asia, respectively. Examination of Mn data over a long-term period indicated that the temporal trends of Mn seen in most cities were fairly constant through time since the 1990s, although some abnormalities were observed in cities of strong man-made activities (e.g., Pohang and Wonju). In light of the severity of airborne Mn pollution in many urban areas, it is desirable to establish an abatement strategy that can help effectively reduce Mn levels.  相似文献   
552.
A mass balance study was performed under controlled field conditions to investigate the phytoremediation of perchloroethylene (PCE) by hybrid poplar trees. Water containing 7–14 mg L?1 PCE was added to the test bed. Perchloroethylene, trichloroethylene, and cis-dichloroethylene were detected in the effluent at an average of 0.12 mg L?1, 3.9 mg L?1, and 1.9 mg L?1, respectively. The total mass of chlorinated ethenes in the water was reduced by 99%. Over 95% of the recovered chlorine was as free chloride in the soil, indicating near-complete dehalogenation of the PCE. Transpiration, volatilization, and accumulation in the trees were all found to be minor loss mechanisms. In contrast, 98% of PCE applied to an unplanted soil chamber was recovered as PCE in the effluent water or volatilized into the air. These results suggest that phytoremediation can be an effective method for treating PCE-contaminated groundwater in field applications.  相似文献   
553.
Thirty months after the Indian Ocean tsunami of 26 December 2004, thousands of families in Aceh Province, Indonesia, remained in temporary barracks while sanitation conditions and non‐governmental organisation support deteriorated. This study sought to determine the factors associated with functional impairment in a sample of 138 displaced and non‐displaced Acehnese children. Using multivariate linear regression models, it was found that displacement distance was a consistent predictor of impairment using the Brief Impairment Scale. Exposure to tsunami‐related trauma markers was not significantly linked with impairment in the model. Paternal employment was a consistent protective factor for child functioning. These findings suggest that post‐disaster displacement and the subsequent familial economic disruption are significant predictors of impaired functioning in children's daily activities. Post‐disaster interventions should consider the disruption of familiar environments for families and children when relocating vulnerable populations to avoid deleterious impacts on children's functioning.  相似文献   
554.
555.
Manila clams, Ruditapes philippinarum, removed from their natural environment and maintained for 9 weeks in continuously immersed conditions exhibited a clear endogenous circatidal rhythm in oxygen consumption. The clams exhibited a semidiurnal rhythmicity in oxygen consumption after showing a diurnal pattern in the first few days (5 to 7 d) of the experiment. The results of the present study indicate that activity rhythms of clams are controlled not only by exogenous factors, but also by an endogenous circatidal periodicity. Received: 8 April 1998 / Accepted: 1 February 1999  相似文献   
556.
Bladder outlet obstructions are a diverse and heterogeneous group of developmental abnormalities that generally involve obstruction of the proximal urethra in the male fetus. Indications for prenatal intervention are few and are usually restricted to the male fetus because bladder outlet obstruction in female fetuses is usually caused by complex cloacal development anomalies. We report on a female fetus with an enlarged bladder and a dilated proximal urethra (known as typical keyhole sign). A vesicoamniotic shunt was performed despite non-reassuring prognostic factors, but the procedure resulted in a successful outcome. We propose that in selected cases of bladder outlet obstruction, fetal intervention should be considered even when the fetus is female. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
557.
Climate change caused by excessive emission of greenhouse gases (GHGs) into the atmosphere has gained serious attention from the global community for a long time. More and more countries have decided to propose their goals such as Paris agreements, to reduce emitting these heat trapping compounds for sustainability. The Asian region houses dramatic changes with diverse religions and cultures, large populations as well as a rapidly changing socio-economic situations all of which are contributing to generating a mammoth amount of GHGs; hence, they require calls for related studies on climate change strategies. After pre-filtering of GHG emission information, 24 Asian countries have been selected as primary target countries. Hierarchical cluster analysis method using complete linkage technique was successfully applied for appropriate grouping. Six groups were categorized through GHG emission properties with major and minor emission sectors based on the GHG inventory covering energy, industrial processes, agriculture, waste, land use change, and forestry and bunker fuels. Assigning six groups using cluster analysis finally implied that the approach to establish GHG emission boundaries was meaningful to develop further mitigation strategies. Following the outcome of this study, calculating amount of reduction potential in suitable sectors as well as determining best practice, technology, and regulatory framework can be improved by policy makers, environmental scientists, and planners at the different levels. Therefore, this work on reviewing a wide range of GHG emission history and establishing boundaries of emission characteristics would provide further direction of effective climate change mitigation for sustainability and resilience in Asia.  相似文献   
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559.
Journal of Material Cycles and Waste Management - The urban mine industry plays an essential role in environmental sustainability to minimize the creation of landfills and to maximize the reuse of...  相似文献   
560.
Environmental Science and Pollution Research - Under the impact of climate change, Taiwan, an island state, has faced the challenges of extreme weather events in recent years. Based on previous...  相似文献   
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