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491.
In most industrialised countries, work-related injury and ill-health presents a major burden to society. Musculoskeletal disorders and stress are the most common reported illness types with those working in some industries more at risk than others. This study aimed to understand the occupational health issues of those working as mountain instructors in the outdoor sector within the UK and to identify the cultural norms and behaviours among this unique occupational group which influence health. Semi-structured, telephone interviews were conducted with 20 qualified mountaineers to gain information on work-related injury and ill-health. The majority of interviewees reported a current work-related musculoskeletal problem. Key factors were identified which prevented effective rehabilitation, including; a ‘macho’ attitude among young instructors, self-imposed extended working hours/days and mismanagement of injuries. Self-employed instructors reported that sick leave after a minor injury or illness was not financially viable. Work-related issues leading to stress were also reported. 相似文献
492.
Giuseppe Mascaro Abdinur Hussein Aubrey Dugger David J. Gochis 《Journal of the American Water Resources Association》2023,59(1):49-70
The National Water Model (NWM) will provide the next generation of operational streamflow forecasts across the United States (U.S.) using the WRF-Hydro hydrologic model. In this study, we propose a strategy to calibrate 10 parameters of WRF-Hydro that control runoff generation during floods and snowmelt seasons, and due to baseflow. We focus on the Oak Creek Basin (820 km2), an unregulated mountainous sub-watershed of the Salt and Verde River Basins in Arizona, which are the largest source of water supply for the Phoenix Metropolitan area. We calibrate the model against discharge observations at the outlet in 2008–2011, and validate it at two stream gauging stations in 2012–2016. After bias correcting the precipitation forcings, we sequentially modify the model parameters controlling distinct runoff generation processes in the basin. We find that capturing the deep drainage to the aquifer is crucial to improve the simulation of all processes and that this flux is mainly controlled by the SLOPE parameter. Performance metrics indicate that snowmelt, baseflow, and floods due to winter storms are simulated fairly well, while flood peaks caused by summer thunderstorms are severely underestimated. We suggest the use of spatially variable soil depth to enhance the simulation of these processes. This work supports the ongoing calibration effort of the NWM by testing WRF-Hydro in a watershed with a large variety of runoff mechanisms that are representative of several basins in the southwestern U.S. 相似文献
493.
《Process Safety and Environmental Protection》2014,92(5):476-485
Current electricity generation mix in Malaysia consists of 58% gas, 33% coal and 9% hydro. It is anticipated that by year 2019, the generation mix will be at 64% coal, 32% gas and 4% hydro. Due to the increase in coal consumption for power generation, there is a critical need to evaluate the health risks for the population living in the vicinity of a coal-fired power plant in Malaysia. To date, such study related to the plant in Malaysia has never been published. In this study, health risk assessment (HRA) for air emission from a coal-fired power plant in Malaysia was carried out. Two pollutants from the Proposed New Environmental Quality (Clean Air) Regulation 201X (Draft) (i.e. SO2 and Hg) were assessed for non-carcinogenic health risk, and two trace elements (i.e. As and Cr) were assessed for carcinogenic health risk. Both short-term and long-term health effects were evaluated. Air dispersion modelling (AERMOD) was used to predict the ground level concentration (GLC) within 10 km radius of the emission source. Based on the HRA, different health risks were identified for short-term and long-term dispersion of the studied pollutants. The findings indicate that a detailed assessment on the short-term and long-term health effects of the emissions from coal-fired power plant in Malaysia with meteorological factor as one of the significant factors influencing the emissions level is needed. 相似文献
494.
以神农架林区木鱼镇茶山上生长的8种不同类型植物为试验材料,于晴天选择其植株上东南朝向的顶部成长叶,采用LI—COR6400便携式光合测定系统、调制叶绿素荧光成像系统(IMAGING-PAMM-Series)及双通道PAM—100测量系统(Dual-PAM-100)和常规方法研究了其叶片特征、光合性能及相互间的关系,将有助于了解神农架植物的光合生产力及其植被管理。结果表明,不同类型植物叶片的叶片特征和光合性能存在明显的物种差异。比叶重(SLW)为乔木〉灌木〉草本;气孔参数以气孔导度(Cond)差异最大;草本植物的光合能力明显高于灌木和乔木,而灌木和乔木间的差异不大;叶绿素含量(Chl)及其组分的差异较小,类胡萝卜素(Car)和花青素含量(Ant)及其与Chl的比值差异极大。不同类型植物叶片特征和光合性能指标的变异系数在7.3%~73.0%间,Chla/Chlb最小,Car/Ant最大;Chla/Chlb、基于叶温的蒸汽压亏缺(VpdL)和胞间C02浓度(Ci)dx于15%,Cond、单位鲜重Car、PSII实际量子产量和PsI非光化学能量耗散的量子产量为40%~50%,单位干重Car、Ant、Chl/Ant和Car/Ant则大于60%,其他指标在20%-40%。相关分析显示,Jpn受Cond、叶片含水量和单位干重Chl的正向调控,Ant和Car对两无决定性作用;PSII和PSI的实际量子产量依赖于ci和Chl,Car过高导致其降低;PSI的光保护受SLW的负调控及单位鲜重Chl和单位干重Car的正调控;光合机构的光损伤受Ci的负调控和Chl/Car的正调控。 相似文献
495.
This paper criticises the conclusions and the unanswered questions in the National Institute of Standards and Technology (NIST)'s official report on the evacuation of the World Trade Center in New York City, United States, on 11 September 2001. It reviews the extent to which the report disregards several conventional statistical methods and comments on the NIST's refusal to share the machine‐readable data file with the scientific community for replication and further analysis. Problems lie in the sampling methods employed, the treatment of missing data, the use of ordinary least squares (OLS) with binary dependent variables, the failure to document the scalability of the scales used, the lack of tests to check for constant error variance, and the absence of overall fit tests of the model. There are also conceptual and theoretical issues, such as the absence in the report of considerations of the influence of group‐level processes and their impact on the collective behaviour of evacuating collectivities. 相似文献
496.
This paper examines the current health policy response to the management of vector-borne disease (VBD), specifically Ross River (RR) virus, in subtropical coastal Australia. It demonstrates the multi-dimensional nature of the VBD problem and considers the value of more sustainable policy responses. The paper provides an integrated exploration of the incidence of RR virus in the context of socio-biophysical interactions and change, climate variability, and possible enhanced threat due to climate change. The study focuses on two subtropical coastal case study regions in Australia. Collectively, the existing and emerging socio-biophysical interactions in these regionsraise questions as to the future risks and management of RR virus, while climate change adds a significant further dimension. The paper demonstrates the need for the incorporation of environmental planning elements, particularly attention to strategic assessment and planning, into the traditional suite of health policy responses given the multi-dimensional nature of the problem and evident socio-biophysical environmental change. 相似文献
497.
Anne Silla 《Safety Science》2012,50(1):62-67
A survey was designed to investigate opinions on railway trespassing of people living close to a railway line. The results showed that 89.2% of the respondents (n = 502) recalled that they had seen trespassing in their neighbourhood and, based on their observations, adults are the largest group trespassing. Overall, 68.9% of the respondents had personal experience of trespassing although 83.5% considered trespassing to be fairly or highly dangerous and 81.0% assumed it to be illegal. The respondents supported countermeasures such as building an underpass or fencing off the tracks, and only a few of them indicated that nothing could be done to resolve the problem. In addition, education in schools on the dangers of trespassing was suggested. These results allow practitioners and researchers to see the problem from a local perspective and thus develop a better understanding. This in turn helps design effective countermeasures. 相似文献
498.
499.
全国第二次土地调查前后中国耕地面积变化的空间格局 总被引:16,自引:2,他引:14
长期以来中国耕地数量受到国内外的高度关注,但是中国的耕地面积到底是多少,一直是个谜,特别是在耕地面积出现几十年持续下降的背景下,全国第二次土地调查结果居然比调查前多出了2亿多亩。论文利用全国第二次土地调查前后的耕地面积数据,从耕地总面积和不同类型的耕地面积两个维度,在不同空间尺度上,对耕地面积数据进行对比分析。研究表明:1)从区域尺度来看,“二调”多出的2亿多亩耕地主要分布在东北、华北与西北地区,其中东北地区几近一半,华南是唯一减少的区域;从省级尺度来看,26个省份耕地面积增加,以东北三省和新疆、内蒙古居多,京沪苏粤陕出现减少,尤以苏粤为甚;从市级和县级尺度来看,耕地增减空间集聚明显,耕地增加的地市和县市均以东北最为集中,耕地减少的地市以珠三角和长三角最为集中,耕地减少的县级单元以粤苏云三省最为集中。2)耕地的三种类型都出现增加,但旱地最多(53%)、水田最少(10%);水田和水浇地均“北增南减”;旱地的增减主要分布在北方,且增减的空间分布都非常集中,东北增加较多,黄淮海平原减少较多。耕地分布重心的持续北移,加剧了水土资源的不协调性,从而影响耕地的质量,未来中国政府在高度关注耕地数量变化的同时,更应强化耕地质量的提高与保护。 相似文献
500.
于2019年8月对中国北京和日本东京城市道路积尘进行了调查。采用磁性分离和电感耦合等离子质谱法对2个城市道路积尘磁性颗粒物中28种金属元素的含量进行了分析,并比较了污染特征和健康风险。结果表明,东京和北京道路积尘中铁(Fe)元素平均含量分别为25.3和21.2 mg/g,磁性颗粒物占积尘比例分别为22.4%和13.0%。东京道路积尘磁性颗粒物受人类活动排放影响较北京显著,其中锌(Zn)和银(Ag)元素含量是北京的7.2和5.6倍。北京道路积尘磁性颗粒物中元素富集率远高于东京,以铬(Cr)、镍(Ni)等金属元素最为明显。东京和北京道路积尘磁性颗粒物的非致癌风险和致癌风险均低于安全阈值,但致癌风险分别达到6.9×10-7和6.3×10-7,接近10-6的可接受水平,应引起相关部门的关注。手口摄入是非致癌金属元素日平均暴露的首要途径,皮肤接触途径的非致癌物健康风险最高,Cr是导致道路积尘磁性颗粒物健康风险的首要元素。 相似文献