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11.

Purpose  

Industrial emissions can raise urban background levels of inhalable Mn particles in an order of magnitude above normal, eclipsing the contribution made by natural sources and traffic.  相似文献   
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This paper summarizes a study evaluating the acceptance and perceived performance of disposable cutlery made from starch-based biodegradable resins relative to nondegradable polystyrene cutlery. Two hundred forty-three sailors onboard three U.S. Navy vessels ate their lunch using either biodegradable cutlery made with resins manufactured by one of two commercial companies or polystyrene cutlery. The cutlery was rated on several sensory and performance dimensions as well as for overall acceptability. Results indicated that sailors rated both the biodegradable and the polystyrene utensils as easy to hold. There were also no differences in the perceived ease of using each of the spoons. However, compared to the polystyrene utensils, both types of biodegradable utensils were viewed as less sturdy, as having a less attractive color, and as being less acceptable overall. The biodegradable forks and knives were also rated as more difficult to use for piercing and cutting food than the polystyrene ones. In addition, several significant differences emerged between the two types of biodegradable cutlery. The results are discussed in terms of the need for continued consumer testing of products developed from biodegradable polymeric materials.  相似文献   
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This study was conducted to evaluate the influence of sorbent modification by synthetic, chemical/thermal weathering on the sorptive behavior of polycyclic aromatic hydrocarbons (PAHs). A clean sandy-clay-loam soil was subjected to Soxhlet extraction and PAH sorptive phenomena were evaluated based on quantity and quality changes in soil organic matter (SOM) and clay minerals. Critical changes in sorption capacity were found to depend on the initial PAH concentrations. Above 7 mg/l, weathering increased the PAH in comparison to that of unmodified soil, whereas it decreased when applied below this concentration. Similarly, less PAH was desorbed from the altered soil when PAH was applied above 7 mg/l. Therefore, when PAH was applied below 7 mg/l, quantitative reduction of sorbent amount (i.e., SOM and clay minerals) by soil weathering governed PAH sorptive behavior. However, when the PAH was applied above the critical limit, qualitative modifications in the sorbents facilitated an opposite trend. Sorbent swelling, removal of competing compounds, and possible changes in surface characteristics by Soxhlet extraction, together with increased concentration gradient effects were factors that resulted in dissimilar PAH sorptive phenomena, pivoting at the critical concentration.  相似文献   
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The increasing demand for environmental information on the global warming impact of products requires a solid methodological framework which guarantees comparability and communicability. The publicly available specification PAS 2050 combines approaches to a variety of greenhouse gas specific assessment issues to deliver a globally applicable product Carbon Footprinting (CF) method, which is expected to be widely accepted. Specifically, this paper aims to demonstrate the implementation of a CF scheme for a common canned mussel product according to PAS 2050 guidelines. A final value of 4.35 kg CO2e per triple pack of round cans of mussels was calculated. Furthermore, this CF study led to identify primary packaging (can production) and mussel shell management as the main activities where efforts should focus for climate change mitigation. Throughout this case study, CF opportunities and drawbacks are discussed. The whole text tries to provide a starting point for both mussel processors and policy makers to benefit from the potential advantages of a responsible use of this increasingly popular tool.  相似文献   
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Mussels as a commercial product involve a range of activities which can be included within four different sub-sectors: culture, dispatch centres, canning factories and, finally, cooking plants. This paper deals with the environmental evaluation of the whole mussel sector from a Life Cycle Assessment approach. The use of exhaustive inventories led to the subsequent environmental characterization of the mussel sector in terms of the contribution observed for each of the sub-sectors. In this sense, the sub-sector associated with dispatch centres presented the largest contributions to the potential environmental impacts, clearly ahead of mussel farming. Furthermore, the sub-sectors of mussel cooking plants and canning factories showed a much lower contribution to the potential environmental impacts. Several improvement potentials were identified from the characterization results, stressing the minimization of the electric energy consumption in dispatch centres. A comparative LCA was performed in order to contrast the environmental performance of the three main commercial mussel products: fresh mussels, canned mussels and frozen mussels. The analysis showed that fresh mussels have the least favourable environmental profile.  相似文献   
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A wide spectrum of genetic causes may lead to nonimmune hydrops fetalis (NIHF), and a thorough phenotypic and genetic evaluation are essential to determine the underlying etiology, optimally manage these pregnancies, and inform discussions about anticipated prognosis. In this review, we outline the known genetic etiologies of NIHF by fetal organ system affected, and provide a systematic approach to the evaluation of NIHF. Some of the underlying genetic disorders are associated with characteristic phenotypic features that may be seen on prenatal ultrasound, such as hepatomegaly with lysosomal storage disorders, hyperechoic kidneys with congenital nephrosis, or pulmonary valve stenosis with RASopathies. However, this is not always the case, and the approach to evaluation must include prenatal ultrasound findings as well as genetic testing and many other factors. Genetic testing that has been utilized for NIHF ranges from standard chromosomal microarray or karyotype to gene panels and broad approaches such as whole exome sequencing. Family and obstetric history, as well as pathology examination, can yield additional clues that are helpful in establishing a diagnosis. A systematic approach to evaluation can guide a more targeted approach to genetic evaluation, diagnosis, and management of NIHF.  相似文献   
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A eutrophication assessment method was developed as part of the National Estuarine Eutrophication Assessment (NEEA) Program. The program is designed to improve monitoring and assessment of eutrophication in the estuaries and coastal bays of the United States with the intent to guide management plans and develop analytical and research models and tools for managers. These tools will help guide and improve management success for estuaries and coastal resources. The assessment method, a Pressure-State-Response approach, uses a simple model to determine Pressure and statistical criteria for indicator variables (where applicable) to determine State. The Response determination is mostly heuristic, although research models are being developed to improve that component. The three components are determined individually and then combined into a single rating. Application to several systems in the European Union (E.U.), specifically in Portugal, shows that the method is transferable, and thus is useful for development of management measures in both the Unites States and E.U. This approach identifies and quantifies the key anthropogenic nutrient input sources to estuaries so that management measures can target inputs for maximum effect. Because nitrogen is often the limiting nutrient in estuarine systems, examples of source identification and quantification for nitrogen have been developed for 11 coastal watersheds on the U.S. east coast using the WATERSN model. In general, estuaries in the Northeastern United States receive most of their nitrogen from human sewage, followed by atmospheric deposition. This is in contrast to some watersheds in the Mid-Atlantic (Chesapeake Bay) and South Atlantic (Pamlico Sound), which receive most of their nitrogen from agricultural runoff. Source identification is important for implementing effective management measures that should be monitored for success using assessment methods, as described herein. For instance, these results suggest that Northeastern estuaries would likely benefit most from improved sewage treatment, where as the Mid and South Atlantic systems would benefit most from agricultural runoff reductions.  相似文献   
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