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1.
Newark Bay, New Jersey, is particularly vulnerable to ecological damage from petroleum and chemical spills, as a result of the enclosed nature and shallow depth of the bay, the high frequency of shipping traffic, and the numerous chemical and petroleum transfer terminals located alongs its shores. To evaluate the potential impacts to the natural resources of this coastal estuarine ecosystem, chemical and petroleum accidents reported to the US Coast Guard (USCG) between 1982 and 1991 were compiled to determine the frequency and volume of these incidents in Newark Bay and in each of its major tributaries. Records obtained from the USCG National Response Center's computerized database indicated that more than 1453 accidental incidents, resulting in the release of more than 18 million US gallons of hazardous materials and petroleum products, occurred throughout Newark Bay during this period of time. The bulk of the materials released to the aquatic environment consisted of petroleum products, specifically No. 6 Fuel Oil (103 spills, 12 829 272 US gal) and gasoline (207 spills, 48 816 US gal). The majority of the reported incidents occurred in the Arthur Kill and its tributaries, as well as in the Kill Van Kull and the Passaic River. The results of this study indicated that the accidental discharge of petroleum and hazardous chemicals represents a significant source of chemical pollution in Newark Bay. Based on the frequency of spills and the volume of materials released to the aquatic environment, it is likely that these events are having a deleterious effect on the Newark Bay ecosystem.  相似文献   
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Despite aquaculture’s contribution providing an additional food source or employment in rural areas, this industry is often presented in a controversial way, including its impact on the environment. However, an argument can also be made in favour of aquaculture operators and their efforts to follow environmentally sound practices. Along these lines, the present study investigates operators’ stance on environmental sustainability from a group of 26 Western Australian marron growers. Overall, the findings demonstrate growers’ commitment to grow marron environmentally, for instance, without the use of fertilisers or feeding. Furthermore, respondents are in agreement with the potential effects of environmentally unfriendly practices, especially as in many cases marron growing is a complement to rural activities such as horticulture and cattle farming. At the other end, some operators voice concerns on a different environmental issue, namely, the challenge that increasing droughts and lack of sufficient rain is posing to their industry.  相似文献   
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Obstetric complications, such as severe pre-eclampsia, fetal growth restriction, abruptio placentae, or stillbirth are associated with abnormally elevated second-trimester maternal serum alpha-fetoprotein (MSAFP) and β subunit of human chorionic gonadotrophin (βhCG). This has been attributed to placental abnormalities. Women with thrombophilias have been shown to have abnormalities of the placenta resulting in adverse pregnancy outcome in these patients. The purpose of the present study was to evaluate whether women with pregnancy complications and inherited thrombophilias have abnormally elevated second-trimester MSAFP or βhCG. Sixty-two women with pregnancy complications were tested for inherited thrombophilias several months after delivery. The thrombophilia group included 29 women with pregnancy complications and an inherited thrombophilia and the control group included 33 other patients without thrombophilia. Patients in the thrombophilia group had a higher median MoM MSAFP compared to the controls (1.337 vs 1.086, p=0.0516). The incidence of abnormally elevated MSAFP (>2.5 MoM) was also significantly higher in the thrombophilia group compared to controls (21% vs 3%, p=0.04). Neither the median MoM βhCG nor the incidence of abnormally elevated βhCG were significantly different between the groups. We conclude that second trimester MSAFP, but not βhCG, is abnormally elevated in patients with thrombophilia and obstetric complications. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Thermophilic-anaerobic digestion in a single-stage, mixed, continuous-flow reactor is not approved in the United States as a process capable of producing Class A biosolids for land application. This study was designed to evaluate the inactivation of pathogens and indicator organisms in such a reactor followed by batch treatment in a smaller reactor. The combined process was evaluated at 53 degrees C with sludges from three different sources and at 51 and 55 degrees C with sludge from one of the sources. Feed sludge to the continuous-flow reactor was spiked with the pathogen surrogates Ascaris suum and vaccine-strain poliovirus. Feed and effluent were analyzed for these organisms and for indigenous Salmonella spp., fecal coliforms, Clostridium perfringens spores, and somatic and male-specific coliphages. No viable Ascaris eggs were observed in the effluent from the continuous reactor at 53 or 55 degrees C, with greater than 2-log removals across the digester in all cases. Approximately 2-log removal was observed at 51 degrees C, but all samples of effluent biosolids contained at least one viable Ascaris egg at 51 degrees C. No viable poliovirus was found in the digester effluent at any of the operating conditions, and viable Salmonella spp. were measured in the digester effluent in only one sample throughout the study. The ability of the continuous reactor to remove fecal coliforms to below the Class A monitoring limit depended on the concentration in the feed sludge. There was no significant removal of Clostridium perfringens across the continuous reactor under any condition, and there also was limited removal of somatic coliphages. The removal of male-specific coliphages across the continuous reactor appeared to be related to temperature. Overall, at least one of the Class A pathogen criteria or the fecal coliform limit was exceeded in at least one sample in the continuous-reactor effluent at each temperature. Over the range of temperatures evaluated, the maximum time required to meet the Class A criteria by batch treatment of the continuous-reactor effluent was 1 hour for Ascaris suum and Salmonella spp. and 2 hours for fecal coliforms.  相似文献   
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Besprechungen     
Nachtsheim  H.  Abel  O.  Kallmann  H.  Hillers  Wilhelm  Erfle  H.  Kniep  H. 《Die Naturwissenschaften》1922,10(11):254-260
The Science of Nature -  相似文献   
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Thomas Abel 《Ecological modelling》2010,221(17):2112-2117
In emergy research, transformities are of fundamental importance. They are factors that are used to convert the inputs to a process into emergy. Once placed in emergy units, the inputs to any process can then be added together or compared. Furthermore, as a product of an emergy analysis, new transformities for outputs can be used in other analyses. By this process the collection of known transformities grows, and subsequent emergy analyses become more accurate. Human labor is often a critical input to an emergy analysis. Transformities for humans have only been roughly estimated based on education level, and should be judged as first approximations. This paper refines the existing values for human services, using similar techniques, but with some different assumptions. The result is a larger range of human transformities, expanded at both lower and upper ends that range from 7.53E4 to 7.53E13. There are many applications of this knowledge, from improving empirical studies to expositions of hierarchy that more reliably “locate” humans, economic production, and information within energy transformation hierarchies.  相似文献   
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