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151.
Cover Image     
The cover image is based on the Original Article Noninvasive prenatal paternity testing by means of SNP-based targeted sequencing by Jacqueline Chor Wing Tam et al., https://doi.org/10.1002/pd.5595 .

  相似文献   

152.
Organochlorines are found even in organisms living in remote areas such as the Arctic marginal ice zone. Organochlorine concentrations in ice-associated (sympagic) amphipods are related to their diet. Therefore, the size-dependent diet shift of Gammarus wilkitzkii may influence its organochlorine content. In this preliminary study, the organochlorine concentrations in two size classes (small 29 mm and large >29 mm) of G. wilkitzkii were analysed. The concentrations of more lipophilic compounds [e.g. polychlorinated biphenyls (PCBs)] were lower in the small than the large size class, whereas concentrations of less lipophilic compounds [e.g. hexachlorocyclohexanes (HCHs)] did not differ by size class.

Since contamination transport by the atmosphere, ocean currents and sea ice may vary, the organochlorine burden in sympagic organisms may also vary. There are no data available on temporal variation of organochlorine burden in Arctic sympagic fauna. Therefore, we compared organochlorine concentrations in sympagic amphipods (G. wilkitzkii, Apherusa glacialis and Onisimus spp.) between 1998 and 1999. Organochlorine concentrations in all amphipods were low in both years, with sum organochlorines from 50.7 to 621.9 ng g−1 lipid weight. The concentrations of hexachlorobenzene (HCB), chlordanes, DDTs and PCBs were higher in 1999 than 1998, whereas the HCH concentrations were lower in 1999 than 1998. The organochlorine concentrations differed between the taxa in both years in a similar increasing manner from A. glacialis to both G. wilkitzkii and Onisimus spp.

In studies of bioaccumulation relative to body size and temporal variation, a thorough interpretation requires samples from several size classes and years. Nevertheless, the present data provide new knowledge on contaminants in Arctic invertebrates where data are scarce.  相似文献   

153.
Increased reliance on the Internet for critical infrastructure and the global nature of supply chains provides an opportunity for adversaries to leverage dependencies and gain access to vital infrastructure. Traditional approaches to assessing risk in the cyber domain, including estimation of impacts, fall short due to uncertainty in how interconnected systems react to cyber attack. This paper describes a method to represent the pathways of disruption propagation, evaluate the macroeconomic impact of cyber threats and aid in selecting among various cybersecurity policies. Based on state of the art agent-based modeling, multicriteria decision analysis, and macroeconomic modeling tools, this framework provides dynamic macroeconomic, demographic and fiscal insights regarding shocks caused by cyber attacks to the regional economy over time. The interlinkage of these models will provide a robust and adaptive system that allows policy makers to evaluate complex issues such as cybersecurity threats and their impacts on the geopolitical, social, environmental, and macroeconomic landscape.  相似文献   
154.
Removal of batteries from solid waste using trommel separation   总被引:4,自引:0,他引:4  
This paper describes the design and testing of a trommel for separation of batteries from solid waste. A trommel is a cylindrical separation device that rotates and performs size separation. It has also been used in areas such as municipal solid waste (MSW) processing, classifying construction and demolition debris, screening mass-burn incinerator ash and compost processing. A trommel has been designed based on size separation to separate household batteries from solid waste, which can then be used as feedstock for alternative applications of solid waste combustion, particularly where the metal content of the product is also a critical parameter, such as the Co-Co process for integrated cement and power production. This trommel has been tested with batches of university office and restaurant wastes against various factors. The recovery efficiency of batteries increases with decreasing inclination angle of the trommel and decreasing rotational speed. A physical characterization of the university solid waste has been performed with a 20-kg sample of the tested waste. It was found that there is a trend of decreasing recovery of batteries with increasing paper composition, and a trend of increasing recovery of batteries with increasing organic materials composition.  相似文献   
155.
This paper reviews recent declines in fish resources and fishing communities in Korea, evaluates major factors of declines, and examines a subsequent community-based revitalization project. Factors leading to depleting fish resources include global regulations, technological advances in fishing, national economic development policies, land reclamation projects, and pollution. The negative economic and societal impact of depleting fish resources is addressed using demographic and income levels of the communities. In response, the state initiated revitalization projects and invested in local fishing cooperatives promoting community-based management. The result has been less than effective as it led to mismanagement of investment and created an attitude of dependence on the government for financial assistance.  相似文献   
156.
电解水制氢技术进展   总被引:9,自引:0,他引:9  
氢能清洁无污染,并且高效,可再生,被视为未来最有潜力的能量载体。在目前的各种制氢技术中,利用可再生能源所产生的电能作为动力来电解水是最为成熟和最有潜力的技术,是通向氢经济的最佳途径。简要介绍了碱性电解槽,聚合物薄膜电解槽,固体氧化物电解槽的基本原理,研究现状,并对有关问题和电解槽的现状,发展趋势作了讨论。  相似文献   
157.
158.
ABSTRACT: The Lower Fox River, Wisconsin, hosts the densest concentration of paper mills in the US., with 18 located along a 4Gde stretch between Lake Winnebago and Green Bay, Lake Michigan. Some of these companies use only primary, others also secondary, waste treatment techniques. Comparison of the quantities of wastes discharged with the legal limits indicates that all plants discharge only 40-50 percent or less of the allowable suspended solids; most discharge < 50 percent of the allowable BOD. This is equal or better than the performance of paper companies elsewhere in the state. Reductions in pollutant discharges have corresponded to improved water quality, though too much BOD is still discharged to be adequately assimilated by the Fox River. The relatively low current level of discharges means permit levels would have to be drastically cut to make any significant impact on water quality. Only a few companies might be seriously affected by such changes. Flow and temperature related permits would likely be more effective, but more difficult to comply with for the industry. Toxic substances are also a potential problem, particularly chlororganic compounds that can form in situ from the chlorine frequently used for pulp bleaching.  相似文献   
159.
The present study aimed at studying the transplantation of oysters from a polluted site Lau Fau Shan (existing oyster culture zone) in Deep Bay to two clean sites mariculture zones at Yung Shue O and Kat O. The hydrological data, growth of oyster shell length, mortality and metal contents in whole soft tissue were monitored from February 1993 to February 1994. The high growth phase (increase in shell length) and gametogenesis (decrease in dry weight of whole soft tissue) were noted in winter (with low temperature and high salinity), and slow growth phase and spawning in summer (with high temperature and low salinity). Significant reductions (p<0.05) of Cd, Cr and Pb concentrations (dry wt basis) in soft tissue of transplanted oysters were observed at Kat O by 29, 55 and 29%, respectively, and at Yung Shue O by 34, 44 and 34%, respectively, with respect to the baseline values for the first batch of oysters and the concentrations in samples collected from Lau Fau Shan in the same months. Maximum reductions of total metal burden in whole soft tissue (microg per individual oyster) of the first oyster batch were found for Cd, Cr, Pb and Sb to be 62, 49, 60 and 25%, respectively, at Kat O, and to be 56, 47, 32 and 49%, respectively, at Yung Shue O. For the second batch of oysters transplanted to Yung Shue O in July 1993, significant reductions (p<0.05) of Cd concentration and total burden of Cd by 60 and 21%, respectively, were observed in February 1994. The high accumulated mortality and the significant (p<0.05) lower growth rate of the transplanted oysters illustrated that the best time for transplantation of oysters should be between the end of gametogenesis and the start of spawning (i.e. January and February), and the oysters should not be kept for longer than 3 months at the transplantation sites.  相似文献   
160.
Wang X  Lu W  Wang W  Leung AY 《Chemosphere》2003,52(9):1405-1410
As far as the impact of air pollutants on human health being concerned, ozone is one of the main pollutants in atmosphere. In particular, the ground level ozone is responsible for a variety of adverse effects on both human being and plant life. To protect the humankind from such adverse health effects, early information and precautions of high ozone level need to be supplied in times. In this study, statistical characteristics of ground level ozone is analyzed according to the field monitoring data in mixed residential, commercial and industrial areas, e.g., Tsuen Wan area in Hong Kong. The study deals with the characteristics of hourly and daily mean ozone levels under different climatic conditions such as temperature, solar radiation, wind speed, and other pollutant concentration levels. The study aims to investigate the importance of meteorological factors and their impact on relevant pollutant concentration levels from chemical aspect. Further, reasons causing the spatial and temporal variations of ozone levels are discussed. All these results will provide a physical basis for accurately predicting ozone concentration in extensive, future research.  相似文献   
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