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171.
The demand for low cost and effective materials to remove contaminants such as residues of oil spills has encouraged studies on new biosorbents produced from wastes. Considering the overgeneration of fishing residues and the necessity to provide an alternative purpose for such materials, this study aimed to evaluate squid gladius and its derivatives (β-chitin and chitosan) as sorbents to remove marine diesel oil (MDO) from fresh and artificial seawater. It was also executed an attempted to improve their performances through a high-intensity ultrasound treatment (UT-gladius and UT-β-chitin). All sorbents removed MDO at both salinities. Contact surface area, salinity, and water retention seemed to play a key role in the outcomes. UT-β-chitin’s performance was significantly superior to β-chitin’s and chitosan’s in MDO removal at salinity 0, as well as at salinity 30, where gladius and UT-gladius also excelled. Ultrasound treatment improved the oil removal performance of UT-β-chitin by increasing its contact surface area. This is the first report on the efficiency of gladius and UT-β-chitin for such purpose, and brought up huge possibilities and new questions that can lead to the achievement of biosorbents of great efficiency.  相似文献   
172.
Tropical forests are vulnerable to climate-change representing a risk for indigenous peoples and forest-dependent communities. Mechanisms to conserve the forest, such as REDD+, could assist in the mitigation of climate change, reduce vulnerability, and enable people to adapt. Ninety-eight interviews were conducted in three countries containing the Congo Basin forest, Cameroon, CAR, and DRC, to investigate perceptions of decision-makers within, and responses of the institutions of the state, private sector, and civil society to the challenges of climate change. Results indicate that while decision-makers’ awareness of climate change is high, direct institutional action is at an early stage. Adaptive capacity is currently low, but it could be enhanced with further development of institutional linkages and increased coordination of multilevel responses across all institutions and with local people. It is important to build networks with forest-dependent stakeholders at the local level, who can contribute knowledge that will build overall institutional adaptive capacity.  相似文献   
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New concerns about biodiversity, ecosystem services and human health triggered several new regulations increasing the need for sound ecotoxicological risk assessment. The PEER network aims to share its view on the research issues that this challenges. PEER scientists call for an improved biologically relevant exposure assessment. They promote comprehensive effect assessment at several biological levels. Biological traits should be used for Environmental risk assessment (ERA) as promising tools to better understand relationships between structure and functioning of ecosystems. The use of modern high throughput methods could also enhance the amount of data for a better risk assessment. Improved models coping with multiple stressors or biological levels are necessary to answer for a more scientifically based risk assessment. Those methods must be embedded within life cycle analysis or economical models for efficient regulations. Joint research programmes involving humanities with ecological sciences should be developed for a sound risk management.  相似文献   
176.
Use of hog (Sus scrofa) manure as a fertilizer is a practical solution for waste re-utilization, however, it may serve as a vehicle for environmental and domestic animal contamination. Work was conducted to determine whether pathogens, naturally present in hog manure could be detected in cattle (Bos taurus) grazed on the manure-treated pasture, and whether forage contamination occurred. During two 3 mo summer trials manure was applied to yield < or = 124 kg available N per hectare in a single spring or split spring and fall application. Samples of hog manure, forage, soil, and cattle feces were analyzed for naturally occurring Salmonella, Yersinia enterocolitica, and Escherichia coli. To follow movement of Salmonella in the environment isolates were identified to serovar and serotyped. Transfer of E. coli from hog manure to soil and cattle was examined by randomly amplified polymorphic DNA (RAPD) analysis of >600 E. coli isolates. While Y. enterocolitica was absent from all samples, in both years S. enterica Derby and S. enterica Krefeld were found in most hog manure samples, but were only on forage samples in the second year. Salmonella enterica Typhimurium, absent from hog manure was present on some forage in the first year. Cattle feces and soil samples were consistently Salmonella negative. These contaminations could not be traced to manure application. During this study, Salmonella and E. coli found in hog manure had different RAPD genomic profiles from those found in the feces of cattle grazing on manure-treated pasture.  相似文献   
177.
Introduction. The effect of different kinds of work on the psychosocial assessment of workers under the same management and organizational environment is investigated. Methods. A voluntary assessment in a utility company was carried out using the short version of the Copenhagen psychosocial questionnaire (CoPsoQ) on two occasions, 1.5 years apart. Initially, 25 office workers (11 men and 14 women) participated, while 14 of those workers (8 women and 6 men) participated in the second assessment together with 32 field workers. The sewage, water treatment and maintenance workers, totaling 32 men, also participated in a field ergonomics assessment using the Washington State Department of Labor and Industries field work ergonomic checklist. Results. The longitudinal outlook was fairly stable, with sustained severe scores in many CoPsoQ subscales and intensification of severity of workers’ control over work and esteem for men. A significantly higher esteem score resulted for field rather than office workers. Workers subjected to foul odors showed similar severity of psychosocial factors. Discussion. For most psychosocial dimensions, the organizational design and management system in place, as well as the overall cultural environment in which it operates, create a much stronger and more decisive impact than job-specific factors.  相似文献   
178.
With 20% of the world’s forests, Russia has global potential in bioeconomy development, biodiversity conservation and climate change mitigation. However, unsustainable forest management based on ‘wood mining’ reduces this potential. Based on document analysis, participant observations and interviews, this article shows how non-state actors—environmental NGOs and forest companies—address forest resource depletion and primary forest loss in Russia. We analyse two key interrelated forest discourses driven by non-state actors in Russia: (1) intensive forest management in secondary forests as a pathway towards sustained yield and primary forest conservation; (2) intact forest landscapes as a priority in primary forest conservation. We illustrate how these discourses have been integrated into policy debates, institutions and practices and discuss their relation to relevant global discourses. The article concludes that despite successful cases in conserving intact forest landscapes, there is still a frontier between sustainable forest management discourses and forestry practice in Russia.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01643-6.  相似文献   
179.
This study presents the conception, modeling, and implementation of a decision support system applied to the operational planning of solid waste collection systems, called SCOLDSS. The main functionality of the system is the generation of alternatives to the decision processes concerning: (a) the allocation of separate collection vehicles, as well as the determination of their routes and (b) the determination of the daily amount of solid waste to be sent to each sorting unit, in order to avoid waste of labor force and to reduce the amount of waste sent to the landfills. To develop the computer system, a combination of quantitative techniques was used, such as: simulation of discrete events and algorithms/heuristics for vehicle allocation and routing. The system was developed using the Borland Delphi environment and the commercial software Arena to carry out the simulations. We also present a computational study with real-life data from the solid waste collection in Porto Alegre, Brazil, in which we show that the results provided by the computational system outperform the operation planning currently adopted.  相似文献   
180.
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