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741.
    
Purpose. The aim of this article was to check whether mindfulness-based stress reduction (MBSR) is an effective intervention in reducing work-related stress in the case of workers in a copper mine. Methods. Sixty six employees were randomized to the experimental group (32 participants) or to the control group (34 participants). Work-related stress was measured using the job content questionnaire (JCQ) and mental health was measured using the general health questionnaire (GHQ-28) Experimental manipulation was 40-h MBSR training. Results. Multivariate repeated-measures analysis of variance revealed a significant increase of JCQ decision latitude (F?=?17.36, p?<?0.001) and social support (supervisor F?=?9.00, p?<?0.004; coworker F?=?5.61, p?<?0.020), and a significant decrease in GHQ-28 anxiety (F?=?5.28, p?<?0.079) and depression (F?=?3.95, p?<?0.048) due to the intervention. Conclusions. The study confirms that MBSR can be effective in reducing stress resulting from the external risk (and/or imagined fear) of losing one’s health or life. The use of MBSR could be recommended in health and safety activities in difficult and dangerous work conditions, such as mining, to promote workers’ well-being.  相似文献   
742.
Little research has been performed on the impact of pesticides on earthworms under tropical conditions. Taking into consideration the often-limited resources in tropical countries, simple screening tests are needed. Therefore, it was investigated whether three pesticides relevant for the Brazilian Amazon (benomyl, carbendazim, lambda-cyhalothrin) affect the avoidance behavior of the earthworm Eisenia fetida. The tests were performed for two days according to ISO guideline 17512 but were adapted to tropical conditions (i.e. test substrate, test organism and temperature). The results indicate that this test gives reproducible and reliable results. Toxicity values (NOEC, EC50) are lower than those determined in 14 day-acute mortality tests and are approximately in the same range such as those found in 56 day-chronic reproduction tests with the same earthworm species, which were performed in parallel. Therefore, the use of the earthworm avoidance tests is recommended as a screening tool for the risk assessment of pesticides.  相似文献   
743.
复林项目的成本决定了它们与其它减轻大气中日益增加的CO2浓度的方法的竞争力.我们量化了南美两国--厄瓜多尔和阿根廷--人工林和次生林地上生物量和土壤中的碳获取量,并计算了短期碳获取成本.每短期认证减排单位成本为0.1~2.7美元/Mg CO2,主要取决于机会成本、立地适宜性、贴现率和认证成本.在厄瓜多尔,次生林是一种可行并合算的方法;在阿根延,在适宜性高的土地上进行复林相对便宜一些.我们的研究结果可用于设计有成本效益的CO2汇项目和为土地所有者协商公平的碳价格.  相似文献   
744.
秸秆焚烧对北京市空气质量的影响   总被引:30,自引:8,他引:30  
用火焰原子吸收光谱法测试了北京市两个采样点 1 #站 (十三陵站 ,清洁对照点 )和 5#站 (天坛站 ,居民生活区 )1 1 0个大气颗粒物样品中的水溶性钾 ,以表征秸秆焚烧颗粒物。 1 #站水溶性钾的质量浓度年均值为 1 .2 1 μg/m3,其中以1 998年 6月份浓度 (3 .0 7μg/m3)最高 ,是 5月份 (1 .0 2μg/m3)的 3倍 ;5#站水溶性钾的质量浓度年均值为 1 .94μg/m3,6月份 (4 .2 2 μg/m3)最高 ,是 5月份 (1 .97μg/m3)的 2 .1倍。数据分析结果表明 1 998年 6月份麦收季节存在以秸秆焚烧为主的生物质燃烧现象 ,使大气颗粒物中有机碳浓度水平升高 ,并对北京市的空气质量带来负面影响  相似文献   
745.
太湖叶绿素a浓度分布的时空特征及其影响因素   总被引:8,自引:0,他引:8       下载免费PDF全文
基于2005—2009年20次太湖采样期间的水质监测数据,研究了太湖叶绿素a浓度的主要分布特征,分析了水环境因子对叶绿素a浓度分布的季节性和空间性影响.结果表明,太湖叶绿素a浓度分布的空间差异较大,主要表现为梅梁湾、竺山湾、太湖西部和西南部湖区为叶绿素a浓度距平经验正交分解(EOF)第一模态空间分布的显著正值区,太湖湖心和东南湖区则为负值区;影响叶绿素a浓度的因子有水温、溶解氧、总氮、磷酸根和总磷,但总磷和水温的影响相对更为显著,而各季节叶绿素a浓度的影响因子则略有差异;影响藻类生长的因子存在较大的空间分布差异,但总磷、水温和溶解氧是其主要限制性因子,氮类营养盐的影响则处于次要地位.  相似文献   
746.
747.
Two kinds of regional disparities can be distinguished in Belgium. First there is the internationally well‐known dispute between Flanders and Wallonia. Secondly, there are large disparities within the regions. Three policy levels deal with these disparities: the (Flemish) regional level, the national government level and the EEC level. The purpose of this paper is to sketch the regional problems in Belgium, to analyse the policies that deal with them, to consider the co‐ordination problems between them and to shed some light on the public choice aspects of government interventions. It is concluded that regional policy in Belgium is a highly politicised affair. Furthermore public attention paid to regional policies has outgrown the importance of our regional disparities. Even other forms of micro‐economic policy are jeopardised by regional disparities and the resulting pressure.  相似文献   
748.
贺词     
环境预防战略,无论是清洁生产、生态效益还是污染防治,是改变不可持续生产和消费方式的最佳战略.自从它被引入《21世纪议程》后,政府和工商业越来越多地采用了清洁生产观念,并且为完善这一概念做出了巨大的努力.  相似文献   
749.
Application of wood plastic composites (WPCs) obtained from recycled materials initially intended for landfill is usually limited by their composition, mainly focused on release of volatile organic compounds (VOCs) which could affect quality or human safety. The study of the VOCs released by a material is a requirement for new composite materials. Characterization and quantification of VOCs of several WPC produced with low density polyethylene (LDPE) and polyethylene/ethylene vinyl acetate (PE/EVA) films and sawdust were carried out, in each stage of production, by solid phase microextraction in headspace mode (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). An odor profile was also obtained by HS-SPME and GC–MS coupled with olfactometry analysis. More than 140 compounds were observed in the raw materials and WPC samples. Some quantified compounds were considered WPC markers such as furfural, 2-methoxyphenol, N-methylphthalimide and 2,4-di-tert-butylphenol. Hexanoic acid, acetic acid, 2-methoxyphenol, acetylfuran, diacetyl, and aldehydes were the most important odorants. None of the VOCs were found to affect human safety for use of the WPC.  相似文献   
750.
Journal of Polymers and the Environment - The objective of this study was to obtain and characterize Nerol essential oil encapsulated in PCL. The miniemulsion and solvent evaporation method was...  相似文献   
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