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141.
Environmental Modeling & Assessment - Extreme or recurrent drought events are the principal source of stress on forests, impairing their overall health. They result in financial losses for...  相似文献   
142.
Food and Environmental Virology - Enteric viruses have been described as important contaminants in fresh and ready-to-eat foods such as sandwiches, deli meat and dairy products. This is a...  相似文献   
143.
Wild polioviruses still remain endemic in three countries (Afghanistan, Pakistan, and Nigeria) and re-emergency of wild polio has been reported in previously polio-free countries. Environmental surveillance has been used as a supplementary tool in monitoring the circulation of wild poliovirus (PVs) and/or vaccine-derived PVs even in the absence of acute flaccid paralysis cases. This study aimed to monitor the presence of polioviruses in wastewater samples collected at one wastewater treatment plant located in the municipality of Rio de Janeiro, Brazil. From December 2011 to June 2012 and from September to December 2012, 31 samples were collected and processed. RD and L20B cell cultures were able to isolate PVs and non-polio enteroviruses in 27/31 samples. Polioviruses were isolated in eight samples (type 1 Sabin = 1, type 2 Sabin = 5, and type 3 Sabin = 2). Vaccine-derived polioviruses were not detected nor evidence of recombination with other PVs or non-polio enterovirus serotypes were observed among the isolates. The Sabin-related serotypes 2 and 3 presented nucleotide substitutions in positions associated with the neurovirulent phenotype at the 5′-UTR. Changes in important Amino acid residues at VP1 were also observed in the serotypes 2 and 3. Environmental surveillance has been used successfully in monitoring the circulation of PVs and non-polio enteroviruses and it is of crucial importance in the final stages of the WHO global polio eradication initiative. Our results show the continuous circulation of Sabin-like PVs and non-polio enteroviruses in the analyzed area during the study period.  相似文献   
144.
Regional Environmental Change - The use and trade of animals in traditional medicine involves many different species, some of which are threatened with extinction. Thus, evaluating biological and...  相似文献   
145.
In the Harghita volcanic range (Romania) there are many occurrences of dry CO(2) emanations, called mofettes. The emanating gas with high carbon dioxide content has a proved curative effect. The gas also contains important quantities of radon. Since the mofettes are used in curative purposes in several illnesses, in most of the cases without medical supervising, has been proposed to determine the radon activity concentration in some of the most frequented mofettes from Romania. The seasonal variations have also been monitored and were calculated the effective doses received by the patients during a cure. The radon activity concentrations' levels above the mofettes indoor air range between 548 and 10 717Bq/m(3) while within the gas pools' values between 3210 and 32 781Bq/m(3) have been measured. The effective dose received by the patients during a cure is between 0.0086 and 0.16mSv. No major seasonal variations of the radon activity concentrations levels have been pointed out so far in the studied mofettes.  相似文献   
146.
A management system for end-of-life tyres: a Portuguese case study   总被引:2,自引:0,他引:2  
The European Union introduced several policy instruments based in the extended producer responsibility (EPR) in order to improve the environmental performance of products and services through their life cycles. In this context, the Portuguese government decided to apply the EPR concept to tyres, and producers were obliged to constitute an end-of-life management system to promote the collection, recycling and reuse of end-of-life (EOL) tyres. This required producers, distributors, recyclers and retreaders to be identified and characterized, and local processing infrastructures to be analyzed. The information was used to design an economically optimised EOL tyre management system while promoting the activity of all EOL operators in order for the imposed collecting and recovery targets to be fulfilled. This paper discusses the interaction between the different governmental, private and academic institutions for the creation of the integrated management system for EOL tyres, the approach taken, the technical, political and legal aspects underneath them, as well as the environmental consequences induced by the creation of the management system. The results obtained during the first years of operation are reported and show an increase in the collection and recycling of EOL tyres and the consolidation of the collection and processing infrastructures.  相似文献   
147.
The establishment of rules to manage Health Care Waste (HCW) is a challenge for the public sector. Regulatory agencies must ensure the safety of waste management alternatives for two very different profiles of generators: (1) hospitals, which concentrate the production of HCW and (2) small establishments, such as clinics, pharmacies and other sources, that generate dispersed quantities of HCW and are scattered throughout the city. To assist in developing sector regulations for the small generators, we evaluated three management scenarios using decision-making tools. They consisted of a disinfection technique (microwave, autoclave and lime) followed by landfilling, where transportation was also included. The microwave, autoclave and lime techniques were tested at the laboratory to establish the operating parameters to ensure their efficiency in disinfection. Using a life cycle assessment (LCA) and cost analysis, the decision-making tools aimed to determine the technique with the best environmental performance. This consisted of evaluating the eco-efficiency of each scenario. Based on the life cycle assessment, microwaving had the lowest environmental impact (12.64 Pt) followed by autoclaving (48.46 Pt). The cost analyses indicated values of US$ 0.12 kg?1 for the waste treated with microwaves, US$ 1.10 kg?1 for the waste treated by the autoclave and US$ 1.53 kg?1 for the waste treated with lime. The microwave disinfection presented the best eco-efficiency performance among those studied and provided a feasible alternative to subsidize the formulation of the policy for small generators of HCW.  相似文献   
148.
Vacuum evaporation consists in the boiling of a liquid substrate at negative pressure, at a temperature lower than typical boiling temperature at atmospheric conditions. Condensed vapor represents the so called condensate, while the remaining substrate represents the concentrate.This technology is derived from other sectors and is mainly dedicated to the recovery of chemicals from industrial by-products, while it has not been widely implemented yet in the field of agricultural digestate treatment. The present paper relates on experimental tests performed in pilot-scale vacuum evaporation plants (0.100 and 0.025 m3), treating filtered digestate (liquid fraction of digestate filtered by a screw-press separator). Digestate was produced by a 1 MWe anaerobic digestion plant fed with swine manure, corn silage and other biomasses. Different system and process configurations were tested (single-stage and two-stage, with and without acidification) with the main objectives of assessing the technical feasibility and of optimizing process parameters for an eventual technology transfer to full scale systems.The inputs and outputs of the process were subject to characterization and mass and nutrients balances were determined.The vacuum evaporation process determined a relevant mass reduction of digestate.The single stage configuration determined the production of a concentrate, still in liquid phase, with a total solid (TS) mean concentration of 15.0%, representing, in terms of mass, 20.2% of the input; the remaining 79.8% was represented by condensate. The introduction of the second stage allowed to obtain a solid concentrate, characterized by a content of TS of 59.0% and representing 5.6% of initial mass.Nitrogen balance was influenced by digestate pH: in order to limit the stripping of ammonia and its transfer to condensate it was necessary to reduce the pH. At pH 5, 97.5% of total nitrogen remained in the concentrate. This product was characterized by very high concentrations of total Kjeldhal nitrogen (TKN), 55,000 mg/kg as average.Condensate, instead, represented 94.4% of input mass, containing 2.5% of TKN. This fraction could be discharged into surface water, after purification to meet the criteria imposed by Italian regulation. Most likely, condensate could be used as dilution water for digestion input, for cleaning floor and surfaces of animal housings or for crop irrigation.The research showed the great effectiveness of the vacuum evaporation process, especially in the two stage configuration with acidification. In fact, the concentration of nutrients in a small volume determines easier transportation and reduction of related management costs. In full scale plants energy consumption is estimated to be 5–8 kWhe/m3 of digestate and 350 kWht/m3 of evaporated water.  相似文献   
149.
草地畜牧业雪灾脆弱性评价 --以内蒙古牧区为例   总被引:16,自引:5,他引:16  
从综合减灾和区域可持续发展的角度,建立了雪灾脆弱性评价指标体系及评价模型,并从雪灾区域孕灾环境敏感性以及区域畜牧业承灾体对雪灾的适应性两方面,对内蒙古雪灾脆弱性进行了评价。研究结果表明:内蒙古牧区雪灾脆弱性存在若明显的地域差异,中西部牧区比东部牧区脆弱性大,北部牧区比南部牧区脆弱性大,并且近10年来脆弱性提高的旗县明显增多,草地季节性干旱、北方干旱化以及草场超载过牧、退化加剧是畜牧业雪灾脆弱性呈增加趋势的直接原因。  相似文献   
150.
Food and Environmental Virology - Norovirus is a major cause of foodborne-associated acute gastroenteritis (AGE) outbreaks worldwide. Usually, food products are contaminated either during...  相似文献   
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