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961.
Objective: Road traffic mortality takes an enormous toll in every society. Transport safety interventions play a crucial role in improving the situation. In the period 1996–2014 several road safety measures, including a complex new road traffic law in 2009, were implemented in the Slovak Republic, introducing stricter conditions for road users.

The aim of this study is to describe and analyze the trends in road user mortality in the Slovak Republic in individual age groups by sex during the study period 1996–2014.

Methods: Data on overall mortality in the Slovak Republic for the period 1996–2014 were obtained from the Statistical Office of the Slovak Republic. Mortality rates were age-adjusted to the European standard population. Joinpoint regression was used to assess the statistical significance of change in time trends of calculated standardized mortality rates.

Results: Mortality rates of all types of road users as well as all age groups and both sexes in the Slovak Republic in the period 1996–2014 are decreasing. The male : female ratio decreased from 4:1 in 1996 to 2:1 in 2014. Motor vehicle users (other than motorcyclists) and pedestrians have the highest mortality rates among road user groups. Both of these groups show a significant decline in mortality rates over the study period. Within the age groups, people age 65 years and over have the highest mortality rates, followed by the age groups 25–64 and 15–24 years old.

Joinpoint regression confirmed a steady, significant decline in all mortality rates over the study period. A statistically significant decrease in mortality rates in the last years of the study period was observed in the age group 25–64 and in male motorcycle users.

Assessing the impact of the 2009 road traffic law, a drop was observed in the average standardized mortality rate of all road traffic users from 14.56 per 100,000 person years in the period 1996–2008 to 7.69 per 100,000 person years in the period 2009–2014. A similar drop in the average standardized mortality rate was observed in all individual road user groups.

Conclusions: The implementation of the new traffic regulations may have contributed significantly to the observed decrease in mortality rates of road users in the Slovak Republic. A significant decrease in mortality was observed in all population groups and in all groups of road users. The introduction of a new comprehensive road traffic law may have expedited the decrease of road fatalities, especially in the age group 25–64 years old. This type of evidence-based epidemiology data can be used for improved targeting of future public health measures for road traffic injury prevention.  相似文献   

962.
珠三角冬季PM2.5重污染区域输送特征数值模拟研究   总被引:4,自引:2,他引:2  
利用嵌套网格空气质量模式系统(NAQPMS)及其耦合的污染来源追踪模块,针对2013年1月珠三角区域的PM_(2.5)重污染过程输送特征进行了数值模拟研究.结果表明,污染气团首先形成于广州、佛山地区,并在弱偏北风的作用下南移加强,影响整个珠三角区域.重污染期间,广州(64.9%)、佛山(58.9%)的PM_(2.5)主要来自本地贡献,是区域输送最主要的来源地区;中山(51.9%)、珠海(66.2%)的PM_(2.5)主要来自外来贡献,是区域输送主要的受体地区.重污染期间,广州和佛山对中山的PM_(2.5)日均贡献率之和总体保持在25%以上,污染最重时达到40%.交通(26%)、工业(24%)、扬尘(16%)、火力发电(15%)和生物质燃烧(8%)是对中山贡献最大的5类源:工业源中山本地与外来输送贡献率基本相当;交通和扬尘源以中山本地贡献为主,贡献率分别为55%和67%;火力发电和生物质燃烧源以外来输送为主,贡献率分别为56%和62%.各类排放源的外来输送中,以广州、佛山所占的比例最大.  相似文献   
963.
填埋场底土污染物浓度实测值和理论解的比较   总被引:3,自引:0,他引:3  
为了研究现场条件下污染物在粘性土中的运移机理,对运行13年的苏州七子山填埋场进行了钻孔取样.通过对土样进行分层切片、加去离子水混合并结合室内小型离心机分离,得到了填埋场底土中Cl-,Na+及COD的孔隙水浓度.将室内试验测试值和一维扩散理论进行了比较,结果表明,实测浓度剖面与扩散曲线差别较大,可见水力梯度引起的对流和机械弥散作用比分子扩散作用来得重要.将实测值与一维对流弥散解析解的计算值亦进行了比较,结果表明试验数据较为发散,但可以采用一维对流弥散理论进行大致的拟合,从而可得到运移参数的取值范围.进一步的理论预测表明,当填埋场运行30年之后,Cl-的影响深度可达到10 m以上.为了防止和延缓渗滤液污染物的进一步运移,填埋场应采取有效措施阻止渗滤液的扩散.  相似文献   
964.
Abstract

Having argued the importance of China's sustainable development in global sustainability, the authors review the achievements of China in sustainable development, especially its institutional construction. Environment to be counted in official's political performance rating system is thought of as a new institutional mechanism in China facilitating its sustainable development and then global sustainability. Then its significance is narrated and visions in future are envisioned. In the end, certain concrete suggestions for the rating system are given in a practical way.  相似文献   
965.
ABSTRACT

This study used hydroponics with different copper (Cu) concentrations to assess metal accumulation and growth in two different populations of Leersia hexandra Swartz, one obtained from a contaminated area (CP) and the other from a non-contaminated area (NCP). Data demonstrated that Cu exerted a lesser effect on the biomass of CP than NCP. The root and shoot biomass measurements of CP were significantly higher than those noted at NCP. Copper concentration in the tissues of L. hexandra from CP increased markedly correlated with the concentration of metal in the culture solution, and this trend was stronger than that in NCP. Copper concentrations in roots and shoots were significantly higher in CP than NCP. As Cu stress levels in the culture solution rose, the transport coefficient of both populations decreased. Furthermore, the coefficient of CP was significantly higher than NCP. At a Cu concentration of 38.4 mg/L, the transfer factor value of CP is 40% higher than NCP. In summary, CP showed higher accumulation and resistance to Cu compared with NCP.  相似文献   
966.
Abstract

This study evaluated the role of water dispersible colloids with diverse physicochemical and mineralogical characteristics in facilitating the transport of metolachlor through macropores of intact soil columns. The soil columns represented upper solum horizons of an Alfisol in the Bluegrass region of Kentucky. Three different colloid suspensions tagged with metolachlor [2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2‐methoxy‐l‐methylethyl)acetamide] were introduced at a constant flux into undisturbed soil columns. The eluents were collected and analyzed periodically for colloid and metolachlor concentrations. Colloid recovery in the eluents ranged from 54 to 90 %. The presence of colloids enhanced the transport of metolachlor by 22 to 70 % depending on the colloid type and mobility. Colloids with higher pH, organic carbon, cation exchange capacity (CEC), total exchangeable bases (TEB), surface area (SA), and electrophoretic mobility (EM), showed better mobility, greater affinity for interaction with the herbicide and, thus, greater potential to co‐transport metolachlor. In contrast, increased level of kaolinite, Fe, and Al inhibited metolachlor adsorption and transport. In spite of the increased transportability of metolachlor by the presence of soil colloids, the colloid bound herbicide portion accounted for a very small part of the observed increase. This suggests that surface site exclusion mechanisms and preferential sorption induced by the presence of colloids are more important than ion exchange phenomena in promoting herbicide mobility in subsurface environments.  相似文献   
967.
从水资源短缺、水环境污染、城市环境污染等多方面分析了滇中城市群的环境脆弱性,在此基础上,提出了滇中城市群可持续发展的对策。  相似文献   
968.
论可持续发展的物质体系   总被引:6,自引:0,他引:6  
可持续发展的物质体系包括资源、环境和生态。可持续发展的终极基础是资源物质变换,可持续发展的生存依托是环境,可持续发展的动态载体是生态平衡网络。本文通过分析资源、环境和生态之间的关系与相互作用,提出了可持续发展的基础是物质体系的观点。  相似文献   
969.
论长江洪灾与可持续发展   总被引:3,自引:1,他引:2  
本文分析了湖北等省份多年水灾资料,并对水灾的成因进行了研究,提出了根治水灾必须走可持续发展道路的建议  相似文献   
970.
The objective of the research was to create improved understanding of the significance of diverse factors for the total greenhouse gas (GHG) emissions of buildings. The specific focus of the study was on the assessment of the significance of building materials and embodied carbon. The scope of the study covers multi-storey residential buildings in Finland. This research was based on a literature survey and supported by a parametric case study. The parametric study assessed the building-material-related GHG emissions relative to total GHG emissions and the possible range of variation. The research assesses the minimum and maximum GHG emissions for production of buildings with similar spaces, to reveal the likely range of variation for the emissions. The calculations for the ‘minimum’ and ‘maximum’ scenarios assume a similar purpose of use, occupancy and spaces in the building, while the production methods, materials, site conditions and location are varied. The research also assesses the relative importance of various building components and other calculation parameters in terms of GHGs. Total material-related GHG emissions were compared with the GHG emissions caused by the operation of the building, at three distinct levels of energy performance. In addition, the material- and operation-related GHG emissions were compared with the location-related GHG emissions arising from people's mobility.  相似文献   
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