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231.
A number of significant developments towards the management of psychosocial risks have been achieved at the policy level in the European Union (EU) since the introduction of the 1989 European Commission Council Framework Directive 89/391/EEC on Safety and Health of Workers at Work on which a new EU risk prevention culture has since been established, combining legislation, social dialogue, best practices and building partnerships. However, it has been widely acknowledged that initiatives aiming to promote workers’ health have not had the impact anticipated both by experts and policy makers and the main reason for this has been the gap that exists between policy and practice. This paper discusses the findings from the PRIMA-EF project, a policy-orientated project, which focussed on the development of a European framework for psychosocial risk management at the workplace. In particular, the paper presents the results of an EU stakeholder survey and interviews with EU policy level experts to assess their awareness, understanding and evaluation of the impact of policy initiatives for psychosocial risk management.  相似文献   
232.
There is a need for a robust and accurate technique to measure ammonia (NH3) emissions from animal feeding operations (AFOs) to obtain emission inventories and to develop abatement strategies. Two consecutive seasonal studies were conducted to measure NH3 emissions from an open-lot dairy in central Texas in July and December of 2005. Data including NH3 concentrations were collected and NH3 emission fluxes (EFls), emission rates (ERs), and emission factors (EFs) were calculated for the open-lot dairy. A protocol using flux chambers (FCs) was used to determine these NH3 emissions from the open-lot dairy. NH3 concentration measurements were made using chemiluminescence-based analyzers. The ground-level area sources (GLAS) including open lots (cows on earthen corrals), separated solids, primary and secondary lagoons, and milking parlors were sampled to estimate NH3 emissions. The seasonal NH3 EFs were 11.6 +/- 7.1 kg-NH3 yr(-1)head(-1) for the summer and 6.2 +/- 3.7 kg-NH3 yr(-1)head(-1) for the winter season. The estimated annual NH3 EF was 9.4 +/- 5.7 kg-NH3 yr(-1)head(-1) for this open-lot dairy. The estimated NH3 EF for winter was nearly 47% lower than summer EF. Primary and secondary lagoons (approximately 37) and open-lot corrals (approximately 63%) in summer, and open-lot corrals (approximately 95%) in winter were the highest contributors to NH3 emissions for the open-lot dairy. These EF estimates using the FC protocol and real-time analyzer were lower than many previously reported EFs estimated based on nitrogen mass balance and nitrogen content in manure. The difference between the overall emissions from each season was due to ambient temperature variations and loading rates of manure on GLAS. There was spatial variation of NH3 emission from the open-lot earthen corrals due to variable animal density within feeding and shaded and dry divisions of the open lot. This spatial variability was attributed to dispirit manure loading within these areas.  相似文献   
233.
234.
The present work proposes a siting process for the detection of a suitable site for wave energy exploitation. The choice of a suitable site is based on the good agreement between energy availability, environmental sustainability, and equipped facilities to exploit wave energy. The case study in the northern Latium coast is explicative because in this area there are several activities that affect marine ecosystems, and the introduction of renewable energies promote the reduction of anthropic pressures. The nearshore wave power is studied through the numerical wave model (CMS-Wave), and available wave buoys along the coast were used to compare numerical results. In correspondence with Civitavecchia harbour, the largest nearshore wave energy was found; the large depth in front of the breakwater allows to conserve a great part of offshore wave power, with an average dissipation rate of 10 % less than offshore, with mean annual available wave energy of 25.4 MWh/m and seasonal fluctuation of 5.4 MWh/m. This area appears to be an optimal site for nearshore and shoreline wave energy device tests and installations, for energy availability (intermediate level respect Mediterreanean Sea), low potential environmental impact, easier accessibility, and policy oriented towards a larger sustainability of harbour activities.  相似文献   
235.
Although human presence is one of the main characteristics of the Mediterranean identity since ancient times, a false dialectic between conservation and social-economic development has emerged in recent decades. On the one hand, an economic growth policy is taken as the paradigm of social-economic development; on the other hand, there is a multi-scale conservation policy, in which natural protected areas, as patches of preserved nature, are used as one of the main tools to deal with the challenge of sustainability. The Mediterranean Basin is the habitat of many unique species and one of the 25 main biodiversity hotspots in the world, and as a consequence a strong conservation policy has been used to protect environmental values. At the same time, Mediterranean countries are deeply involved in promoting strong economic growth policies, which are not always compatible with environmental ones. In this paper, Spain has been studied as one model of this situation. Due to political reasons, Spanish economic growth and conservationist policies were pursued together during the last 20 years. As a result, Spain owns one of the largest networks of natural protected areas in Western Europe, and at the same time it has experienced one of the strongest periods of economic growths in the European and Mediterranean context during the 1980s and 1990s. An historical series of resource use in five annual periods in the last 20 years of conservation policy, and the effects on the preservation of natural capital have been investigated by means of the eMergy (spelled with an 'm') synthesis approach, which was used to characterize the flow of environmental services supplied by ecosystems, but not in monetary terms. This study shows that Spain is becoming less self-sufficient and more inefficient in resource use, comprehensively measured in eMergy terms. A large part of Spain's economy depends on imported goods and services, and most economic activities are based on tourist services and associated construction, which promotes intensification in the urban use of the territory and more intense environmental impacts and resource use intensification of those countries supplying the raw materials. The consequence is a decoupling of the Spanish economy from local environmental services and the increase of Ecological footprint of Spain, measured by means of eMergy-based indicators. In spite of the increase in number, area and associated budget of the natural protected areas and other conservation measures, the general sustainability of the nation is decreasing.  相似文献   
236.
Chromium, nickel, copper, zinc and cadmium were determined in sediments of the Niger Delta (Nigeria) in order to discriminate between natural metal sources and anthropogenic ones. Surface sediments were collected at seven sites along a new gas pipeline near Port Harcourt, between the New Calabar River and the Bonny River towards Bonny town. Chemical characterisation is obtained by hydrofluoric–nitric acid digestion procedure, providing the ‘total’ (‘residual’) metal contents. Information about the anthropogenic metal fraction was obtained by cold diluted hydrochloric acid extraction procedure. This ‘labile’ acid soluble fraction of metals, perhaps due to relatively recent inputs in the sediments, constitutes the fraction more likely to be available to marine organisms, and furnishes a first evaluation of the possible toxicity of sediments of this sensitive ecosystem. Zinc appears to be the most available of all the heavy metals: its ‘labile’ fraction attains 40–50% of the ‘total’ zinc in sediment. Sites near Port Harcourt city are the most contaminated. All the examined metals are one order of magnitude below the respective values proposed as a limit for toxicity and are comparable with those observed by other authors in similar Niger Delta areas. Some anomalous data found near Port Harcourt city suggest that zinc and cadmium are the metals that require further monitoring. Their anthropogenic source could be derived from urban and industrial sewage.  相似文献   
237.
238.
Post-Triassic theropod, sauropodomorph, and ornithischian dinosaurs are readily recognized based on the set of traits that typically characterize each of these groups. On the contrary, most of the early members of those lineages lack such specializations, but share a range of generalized traits also seen in more basal dinosauromorphs. Here, we report on a new Late Triassic dinosaur from the Santa Maria Formation of Rio Grande do Sul, southern Brazil. The specimen comprises the disarticulated partial skeleton of a single individual, including most of the skull bones. Based on four phylogenetic analyses, the new dinosaur fits consistently on the sauropodomorph stem, but lacks several typical features of sauropodomorphs, showing dinosaur plesiomorphies together with some neotheropod traits. This is not an exception among basal dinosaurs, the early radiation of which is characterized by a mosaic pattern of character acquisition, resulting in the uncertain phylogenetic placement of various early members of the group.  相似文献   
239.
This article assesses the impact of extensive deployment of indigenous and external renewable energy sources on a local electricity system (Sardinia Island) and discusses the main challenges faced by the European power grids in integrating high shares of renewable-based generation technologies. It presents the 2030 scenarios for the Sardinian power system and the results of steady-state analyses in extreme (renewable) generation and consumption conditions. These results are eventually combined with the assessment of key technology development trends to explain how this can affect the development of a European supergrid. In general, the article stresses that rendering the bulk-power system capable of accommodating high renewable energy penetration not only requires reinforcing the electricity highways but also demands carefully planning the architecture of and the interface with regional power systems.  相似文献   
240.
ABSTRACT

A 1999 ordinance by the Government of Mexico City bans 1993 model-year vehicles from on-road operation if their catalytic converters are not replaced with new ones. To validate the benefits of this action, we examined three issues related to exhaust emissions of vehicles equipped with catalytic converters. After selecting representative fleets of in-use vehicles, a comparison between emissions and catalyst efficiency in cars with two categories of exhaust emission limits was carried out. For that purpose, two fleets were selected, each made up of 10 vehicles run under similar conditions. A third, larger fleet with emissions control systems was used to evaluate and simulate real-world conditions of vehicles in a controlled laboratory. Finally, the aging effect on the catalytic converter was studied on vehicles run for 100,000 km, replacing their old emission control devices for new ones.

The 1991-1992 model-year vehicles showed a high percentage of compliance with the corresponding emissions standard (90%) in comparison with 1993 model-year and later vehicles (Tier 0). However, NOx emissions were higher for the newer vehicles. Fifty percent of the 1991-1992 model-year vehicles evaluated under the official inspection/maintenance (I/M) procedure did not meet the regulated emissions standard when the results were compared with those of the U.S. Federal Test Procedure  相似文献   
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