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21.
Three groups of data entry female visual display terminal (VDT) workers from Norway (n = 30), Poland (n = 33) and the USA (n = 29) were compared. Before intervention, the Norwegian group reported more neck pain compared with the Polish group. The Polish group reported less shoulder pain than both the U.S. and the Norwegian groups. The clinical examination documented fewer symptoms and signs of musculoskeletal illness among the Polish participants compared with the Norwegian and the U.S. groups. After intervention, the Norwegian group reported a reduction in neck pain while the U.S. group reported a reduction in shoulder pain. The Polish group reported an increase in neck, shoulder and forearm pain at follow-up compared to after intervention. The Polish group recorded higher flexion of the upper arm at follow-up parallel with an increase of pain in the upper part of the body. Visual discomfort showed variable results in the 3 countries.  相似文献   
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Effective selective collection (SC) has been increasing in many countries of the European Union. As a consequence the composition of residual municipal solid waste (RMSW) is changing not only because of economic development, but also due to the collection system. The input of RMSW treatment plants is thus not homogeneous. This paper analyses two case studies involving a total of five SC scenarios and their impact on the generation of solid recovered fuel (SRF) with/without bio-drying, post-treatment and packaging take back programs (TBPs). These case studies are based on two types of SC: kerbside and drop-off. The latest regulation on SRF classification is taken into account: energy content, Cl and Hg concentrations are assessed and discussed. The role of the respirometric index (RI) is also analyzed. Results show that when SC is highly efficient RMSW can be classified directly as SRF, but only if the introduction of RI does not set stringent respirometric targets. The role of packaging TBPs is important as the residual waste remaining after the packaging has been processed, can be valorized increasing the lower heating value (LHV) of the residual RMSW and minimizing the streams that should be landfilled. The source separation of food waste has a significant impact on the suitability of bio-drying: when the SC of food waste is very efficient, its percentage in the RMSW may be too low for effective bio-drying.  相似文献   
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In general, tourism plays a significant role in the economy of archipelagos and islands. The Autonomous Region of the Azores has a great potential for tourism, offering multiple attractions, both natural and cultural, creating a big challenge for a sustainable tourism policy since little attention has been paid to the archipelagos and their special needs. This work aims to understand the profile and type of ecotourist that visits the Azores. This knowledge is of great importance for a better management and development of nature-based tourism, and products tailored to the needs and expectations of visitors. The data were collected by means of exit surveys conducted at the Airport of São Miguel Island, the larger and most populated island of the archipelago, during the high tourist season—July–September 2009. The analysis of the visitor’s profile and preferences is crucial to draw adequate strategies of management for tourism, while it helps to adequate the offer to the demand. Results showed that 41.1 % of the tourists claimed to be attracted to the islands due to their “natural values” (e.g., landscape, biodiversity, and geodiversity). The most practiced activities were whale-watching (32.4 %) and mountaineering/hiking (31.6 %), followed by diving (7 %) and other sports (5.1 %). The tourists’ profile points to a mainstream, soft, and incidental type of ecotourist. This information helps to develop and support a strategic planning and management, both at local and regional levels, for sustainable tourism policies.  相似文献   
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Environmental Science and Pollution Research - The development of mycorrhized pine seedlings grown in the presence of lead was assessed in order to investigate how higher plants can tolerate lead...  相似文献   
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City bus drivers spend hours driving under time pressure, in congested traffic and in a monotonous sitting position. This leads to unhealthy working conditions, especially in terms of physical and psychological stress. The aim of this study is to investigate whether an active steering system can alleviate the musculoskeletal stress involved in manoeuvring a bus. Twenty bus drivers drove a city bus equipped with the Volvo dynamic steering (VDS) support system in real traffic. Steering effort was evaluated with electromyography and with a questionnaire. Compared to baseline, VDS significantly reduced the required muscle activity by on average 15–25% while turning, and up to 68% in the part of the manoeuvre requiring maximum effort. The bus drivers believed that VDS will help reduce neck and shoulder problems, and they expressed a desire to have VDS installed in their own bus.  相似文献   
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Environmental Science and Pollution Research - Methylmercury (MeHg) is a well-known environmental pollutant associated with neurological and developmental deficits in animals and humans. However,...  相似文献   
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Designing connected landscapes is among the most widespread strategies for achieving biodiversity conservation targets. The challenge lies in simultaneously satisfying the connectivity needs of multiple species at multiple spatial scales under uncertain climate and land‐use change. To evaluate the contribution of remnant habitat fragments to the connectivity of regional habitat networks, we developed a method to integrate uncertainty in climate and land‐use change projections with the latest developments in network‐connectivity research and spatial, multipurpose conservation prioritization. We used land‐use change simulations to explore robustness of species’ habitat networks to alternative development scenarios. We applied our method to 14 vertebrate focal species of periurban Montreal, Canada. Accounting for connectivity in spatial prioritization strongly modified conservation priorities and the modified priorities were robust to uncertain climate change. Setting conservation priorities based on habitat quality and connectivity maintained a large proportion of the region's connectivity, despite anticipated habitat loss due to climate and land‐use change. The application of connectivity criteria alongside habitat‐quality criteria for protected‐area design was efficient with respect to the amount of area that needs protection and did not necessarily amplify trade‐offs among conservation criteria. Our approach and results are being applied in and around Montreal and are well suited to the design of ecological networks and green infrastructure for the conservation of biodiversity and ecosystem services in other regions, in particular regions around large cities, where connectivity is critically low.  相似文献   
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The co-digestion of a variable amount of fruit and vegetable waste in a waste mixed sludge digester was investigated using a pilot scale apparatus. The organic loading rate (OLR) was increased from 1.46 kg VS/m3 day to 2.8 kg VS/m3 day. The hydraulic retention time was reduced from 14 days to about 10 days. Specific bio-methane production increased from about 90 NL/kg VS to the maximum value of about 430 NL/kg VS when OLR was increased from 1.46 kg VS/m3 day to 2.1 kg VS/m3 day. A higher OLR caused an excessive reduction in the hydraulic retention time, enhancing microorganism wash out. Process stability evaluated by the total volatile fatty acids concentration (mg/l) to the alkalinity buffer capacity (eq. mg/l CaCO3) ratio (i.e. FOS/TAC) criterion was <0.1 indicating high stability for OLR <2.46 kg VS/m3 day. For higher OLR, FOS/TAC increased rapidly. Residual phytotoxicty of the digestate evaluated by the germination index (GI) (%) was quite constant for OLR < 2.46 kg VS/m3 day, which is lower than the 60% limit, indicating an acceptable toxicity level for crops. For OLR > 2.46 kg VS/m3 day, GI decreased rapidly. This corresponding trend between FOS/TAC and GI was further investigated by the definition of the GI ratio (GIR) parameter. Comparison between GIR and FOS/TAC suggests that GI could be a suitable criterion for evaluating process stability.  相似文献   
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