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991.
The debate concerning occupational safety and health (OSH) interventions has recently focused on the need of improving the evaluation of interventions, and in particular on the need for providing information about why the intervention worked or not, under what circumstances and in which context. Key concepts in the analysis of the context are the drivers, i.e., those factors enabling, fostering or facilitating OSH interventions. However, the concept of driver for an OSH intervention is both confused and contested. Although the term is widely used, there is little consensus on how drivers should be understood, how important they are in different contexts and how they can facilitate interventions. This exploratory study based on interviews with the owner-managers and the safety officers of small and medium-sized enterprises (SMEs) gives an overview of the most characteristic drivers for OSH interventions. The results will be used to make an initial evaluation of SMEs' needs, and will help orient interventions and future research.  相似文献   
992.
The concept of resilience has become very popular, especially in the 21st century. This concept is applicable to many fields, from mechanics to a broad range of social sciences. Resilience has even become part of the national and global policies of the USA, the United Nations and the European Commission. The concept of resilience has also been implemented in the area of safety and health based on the criticism of the traditional approach to occupational safety and health, which does not result in a satisfactory level of occupational safety. The concept of resilience was adopted to research occupational safety and health in different fields and thus with different approaches, such as via socio-technical studies, the psychological and behavioral aspects of organizational resilience and the link with research on individual or family resilience and its influence on work.  相似文献   
993.
Objective: The objective of this study was to determine the prevalence of alcohol and illicit drug use among victims of fatal traffic accidents in the Metropolitan Region of Vitória, Brazil, during the period 2011–2012.

Methods: Blood samples were collected and analyzed for the presence of drugs from 391 deceased victims of traffic crashes that occurred in the Metropolitan Region of Vitória, Brazil. The victims included drivers, passengers, and pedestrians. Sociodemographic variables such as age, gender, day of the week, and period of the year in which the accidents occurred were recorded. The analyses were performed by a gas chromatography–flame ionization method for alcohol and by a gas chromatography–mass spectrometry for amphetamines, cocaine, and cannabis.

Results: The results showed that 44.8% (n = 175) of all cases were positive for alcohol and/or illicit drugs. The detection of alcohol and/or drugs was more frequent in young males, aged 17 to 34, whose samples were positive in 46.8% of cases. Small differences among drivers, passengers, and pedestrians were observed (drivers = 45.9%, passengers = 46.4%, and pedestrians = 45.6%). In general, the most prevalent drug was alcohol, with 141 positive cases (36.1%), followed by cocaine, with 47 positive cases (12%). Amphetamines and cannabis had positivity rates of 4.1 and 4.3%, with 16 and 17 positive cases, respectively. The combined use of alcohol and other drugs was found in 36 cases (9.2%). Crack cocaine use was observed in 27.7% of the positive cases for cocaine.

Conclusions: For the effective reduction of traffic accidents related to driving under influence of drugs (DUID), we suggest the intensification of enforcement actions against the use of alcohol by drivers, the definition of which illicit drugs should be surveyed, as well the cutoff values, the promotion of changing legislation to oblige drivers to provide samples for toxicological testing, and the establishment of public information programs and specific actions aimed at young drivers to promote behavioral changes.  相似文献   

994.
Emitted exhaust gases from aircraft are an issue of concern from an environmental perspective. Many research studies have been conducted aiming to reduce aircraft emissions in the hope of preventing any further increase in climate change and global warming. Within this scope, the present study intends to present a methodology for an optimum gas turbine engine selection with regard to emitted exhaust gases. The methodology focuses on five different turbofan engines which constitute the power unit of a commonly used passenger aircraft. At the end of the study, it is considered to be impossible to achieve a minimum exhaust emission for each gas. For this reason, it is considered to be better to optimize the engine with the aim of reducing nitrogen oxide emissions or other exhaust emissions.  相似文献   
995.
The ecological value of some fine-scale landscape elements tends to be overlooked when they are found in highly human-influenced landscapes, such as peri-urban agricultural ones. These landscapes usually fall beyond the scope of the defined categories of landscape protection, and are thus mapped as areas of little or no ecological interest in the context of extensive analysis. In this paper, we present a method for assessing and visualizing the existing nodes in the field pattern of a peri-urban agricultural landscape. Nodes are identified from the field pattern and characterized according to the presence of relevant features and land uses from the viewpoint of their ecological functions. The method is applied in the Vega del Guadalfeo (south of Spain). Our results show an innovative map of the Vega which may be interpreted as its eco-structure; a model based on nodes to represent the ecological value of the peri-urban agricultural landscape.  相似文献   
996.
温度、pH值及盐度对龙须眼子菜吸附镉、铅的影响   总被引:2,自引:0,他引:2  
以龙须眼子菜(Potamogeton pectinatus)干样为材料,研究了不同温度、pH值和盐度对龙须眼子菜吸附镉、铅离子的影响.结果表明,不同温度及不同pH值下龙须眼子菜对镉吸附符合Langmuir模型,对铅的吸附符合Freundlich模型.与5 ℃、10 ℃、30 ℃处理相比,20 ℃时龙须眼子菜对镉、铅的吸附能力较强.当其它条件不变时,在pH值为3~7的范围内,龙须眼子菜对镉的吸附随pH值升高而增加,对铅的吸附随pH值升高而减少.在0.5~10 g·L-1的盐度范围内,随着溶液盐度的增加龙须眼子菜对镉吸附减少,但对铅的吸附却增加.龙须眼子菜是一种对镉、铅有很强的吸附能力的沉水植物,对温度、酸碱度、盐度适应范围也很广,因而可作为生物吸附剂用于含镉、含铅废水的处理.  相似文献   
997.
To assess the interaction between testosterone (T) treatment and acclimation to different salinities, seawater-acclimated gilthead sea bream (Sparus auratus) were implanted with slow-release coconut oil implants alone (control) or containing T (5 μg/g body mass). After 5 days, eight fish of control and T-treated groups were sampled. The same day, eight fish of each group were transferred to low salinity water (LSW, 6 ppt, hypoosmotic test), seawater (SW, 38 ppt, control test) and high salinity water (HSW, 55 ppt, hyperosmotic test) and sampled 9 days later. Gill Na+, K+-ATPase activity increased in HSW-acclimated fish with respect to SW- and LSW-acclimated fish in both control and T-treated groups. Kidney Na+, K+-ATPase activity was also enhanced in HSW-acclimated fish, but only in T-treated group. From a metabolic point of view, most of the changes observed can be attributed to the action of salinity and T treatment alone, since few interactions between T treatment and osmotic acclimation to different salinities were observed. Those interactions included in treated fish: in the liver, decreased capacity in using glucose in fish acclimated to extreme salinities; in the gills, decreased capacity in using amino acids in HSW; in the kidneys increased capacity in using amino acids in extreme salinities; and in the brain, decreased glycogen and acetoacetate levels of fish in LSW.  相似文献   
998.
In estuaries, eelgrass meadows contribute to fundamental ecosystem functions of estuaries, providing food to several predators and buffering the negative effects of eutrophication. We asked whether the presence of the eelgrass Zostera noltii decreased the nitrogen concentration in the overlying water, affected the sources of nitrogen sequestrated by primary producers and changed the benthic and pelagic food web structures. We also studied the importance of these food webs in providing food to fish. We compared bare sediment to sediment covered by a Z. noltii meadow, and examined nutrient concentrations in the water column and δ15N in primary producers as indicators of anthropogenic inputs of nutrients. We then measured both δ13C and δ15N in the tissues of plants and consumers to establish food web structures. There were no differences in the concentrations and sources of nitrogen between sites. Rather, δ15N values indicated anthropogenic inputs of N (e.g. sewage discharges, agriculture) in both sites. There were no major differences in the structure of the planktonic food web, which was in part sustained by particulate organic matter and supported most predator fish, and in the structure of the benthic food web. Nonetheless, there were differences in the sources of food for omnivore consumers and for the detritivore Scrobicularia plana. Overall, the benthic food web did not use food derived from the eelgrass or macroalgae deposited on the substratum. Suspension feeders used particulate and sediment organic matter, whereas the δ13C and δ15N values of the other consumers indicated a likely contribution of benthic microalgae. Furthermore, in both habitats we found large variability in the isotope signatures of benthic macrofauna consumers, which did not allow distinguishing clearly different trophic groups and indicated a high level of omnivory and a mixed diet opportunistically making use of the availability of food in the surroundings.  相似文献   
999.
分子结构在腐殖酸对菲吸附行为中的影响   总被引:13,自引:0,他引:13  
用连续碱提取具有不同结构组成特征的腐殖酸级分,考察了分子结构在腐殖酸对菲吸附行为中的影响,结果表明:随着腐殖酸中元素碳、表观分子量以及脂肪碳含量的增加,腐殖酸对菲的吸附能力和吸附的非线性特征都呈增强趋势;相反,随着腐殖酸中元素氧和芳香碳含量的增加,腐殖酸对菲的吸附能力和吸附的非线性都逐渐减弱,这主要与结构中极性官能团所连位置有关.  相似文献   
1000.
燃煤氟中毒地区民用高氟煤的氟释放规律   总被引:5,自引:0,他引:5  
实验室模拟实验和农户家中的现场测定表明,室内空气氟含量与民用煤的氟含量呈正相关趋势(R=0.612, p<0.01);但在民用炉燃烧温度条件下的煤氟释放率却与煤氟含量无关.在200~1200℃范围内,煤氟释放率随温度的变化曲线呈"S"型,即300℃时开始逐渐上升,700℃前较低,最高不超过31%,700℃至1000℃之间,则释放率迅速上升,随后较为缓慢,到1100℃至1200℃时,释放率接近100%,其整个释放曲线可用Logistic方程来拟合.总体上,煤氟释放与煤氟的存在状态和煤中的矿物及化学组成有关,贵州烟煤、无烟煤氟的燃烧释放要比陕南石煤更快,前者的释放率在1100℃时就接近100%,而后者则到1200℃时才释放完全.民用炉的燃烧温度最高为1000℃左右,这时贵州烟煤、无烟煤样品的平均氟释放率为86.9%,而陕南石煤样品的平均氟释放率为80.6%.  相似文献   
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