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481.
Graduate researchers are an essential part of higher education (HE) in terms of its contribution to knowledge and the wider economy, but how the work environment influences behaviour and productivity in this work domain is poorly understood. Nevertheless, building programmes continue with a detectable trend towards more open office designs. Beyond issues of cost-efficiency, this reflects a popular belief in the significance of face-to-face interaction to research productivity. Using a combination of subjective and quantitative methods, this case study investigates the validity of this claim and how a redesigned environment impacts upon work practices and collaboration within a community of researchers. Although the new environment was judged favourably by occupants and managers, analysis suggests a less positive behavioural response. Contrary to expectation, we conclude that providing open plan environments is not sufficient to produce more collaborative practices in HE. We argue that this would require changes in the organisational structure, the reward structure for individual and team-driven tasks, and the firm policing of the management of change.  相似文献   
482.
本文根据某大型航运企业最近9年来发生的船员劳动工伤事故,按“企业职工伤亡事故分类标准”中的分类方法,对这些船员劳动工伤事故进行分类统计分析,并提出如何从管理角度,防范此类劳动工伤事故的发生.指出防止船员劳动工伤事故的管理性措施包括:建立船员职业健康安全管理体系,为船员提供一个健康的、安全的、卫生的工作场所;制定配套的船员劳动安全规章制度;建立完善的劳动安全监督机制;加强对船员劳动工伤事故的调查分析;加强安全教育和现场监督管理;进行船员劳动安全风险辨识;为船员提供必要的劳动防护等.  相似文献   
483.

Objective

Pedicabs are a new and controversial transportation innovation for tourists in congested areas in several U.S. cities. Scant literature on this trauma mechanism exists. The purpose of this study is to identify the incidence, demographics, morbidity, mortality, and potential for injury prevention of pedicab incidents amongst major trauma admissions at an urban, academic Level I Trauma Center.

Patients & Methods

Researchers conducted a retrospective review of the Trauma Registry from 2000 to 2009. All patients identified as being injured in a pedicab incident were reviewed. Demographics, diagnoses, toxicology, treatments, and injury severity scale (ISS) were collected. Outcomes included mortality, ICU, and hospital length of stay (LOS), discharge disposition, and hospital charges. A photographic survey of 50 local pedicabs was examined for the presence and use of safety equipment.

Results

During the period of January 2000 to July 2009 there were 15 major trauma victims from identified pedicab incidents. Falling from the pedicab was the mechanism of injury in 14 of 15 cases. There were two fatalities in victims following severe traumatic brain injury. Traumatic brain injury, skull fracture, or loss of consciousness was seen in 11/15 victims. Ethanol ingestion was detected in blood tests of 10 of the 14 adult victims. Median charges of hospitalization due to a pedicab related injury was US$29,956 ± 77,482. A photographic survey of 50 local pedicabs reveals very limited use of safety belts by passengers despite existing city ordinances.

Conclusions

Major trauma victims of pedicab incidents in the United States suffer significant injuries and death. Most cases occurred in passengers falling from the pedicab at night after alcohol ingestion. There is an opportunity for implementation of strategies toward improved injury prevention with this new form of transport.  相似文献   
484.
为建立苯暴露风险的定量研究方法,利用生理药代动力学(PBPK)模型与剂量—反应关系,进行苯暴露的致癌风险评价。采用美国环保署推荐的PBPK模型模拟软件,计算苯经吸收转化后进入人体的数据。将模拟得到的内剂量代入致癌风险计算公式中,得到苯暴露的致癌风险,并利用蒙特卡洛模拟方法确定风险概率分布,进行不确定性分析。最后将此健康风险评价方法应用于天津某大型石油化工企业,分析工人苯暴露下的致癌风险。结果表明,工人苯暴露的致癌风险明显超过了最大可接受风险值1×10-4,需要采取相关措施降低风险。  相似文献   
485.

Introduction

The current study explored the association between the business cycle and the incidence of workplace injuries to identify cyclically sensitive industries and the relative contribution of physical capital and labor utilization within industries.

Method

Bureau of Labor Statistics nonfatal injury rates from 1976 through 2007 were examined across five industry sectors with respect to several macroeconomic indicators. Within industries, injury associations with utilization of labor and physical capital over time were tested using time series regression methods.

Results

Pro-cyclical associations between business cycle indicators and injury incidence were observed in mining, construction, and manufacturing but not in agriculture or trade. Physical capital utilization was the highest potential contributor to injuries in mining while labor utilization was the highest potential contributor in construction. In manufacturing each effect had a similar association with injuries.

Conclusion

The incidence of workplace injury is associated with the business cycle. However, the degree of association and the mechanisms through with the business cycle affects the incidence of workplace injuries was not the same across industries.

Impact on Industry

The results suggest that firms in the construction, manufacturing, and mining industries should take additional precautionary safety measures during cyclical upturns. Potential differences among industries in the mechanisms through which the business cycle affects injury incidence suggest different protective strategies for those industries. For example, in construction, additional efforts might be undertaken to ensure workers are adequately trained and not excessively fatigued, while safety procedures continue to be followed even during boom times.  相似文献   
486.
Objective: Low bone quality is a contributing factor to motor vehicle crash (MVC) injury. Quantification of occupant bone mineral density (BMD) is important from an injury causation standpoint. The first aim of this study was to validate a technique for measuring lumbar volumetric BMD (vBMD) from phantomless computed tomography (CT) scans. The second aim was to apply the validated phantomless technique to quantify lumbar vBMD in Crash Injury Research and Engineering Network (CIREN) occupants for correlation with age, fracture incidence, and osteopenia/osteoporosis diagnoses.

Methods: Quantitative CT (qCT) and dual-energy X-ray absorptiometry (DXA) were collected prospectively for 50 subjects and used to validate a technique to measure vBMD from 281 phantomless CT scans of CIREN occupants. Hounsfield unit (HU) measurements were collected from the L1–L5 vertebrae, right psoas major muscle, and anterior subcutaneous fat for all subjects and from 3 phantom ports with known mg/cc calcium hydroxyapatite values for the validation group. qCT calibration was accomplished using regressions between the phantom HU and mg/cc values to convert L1–L5 HU values to mg/cc. A phantomless calibration technique was developed where the fat and muscle HU values were linearly regressed against fat (?69 mg/cc) and muscle (77 mg/cc) to establish a conversion for L1–L5 HU measurements to mg/cc. vBMD calculated from qCT versus the phantomless method was compared for the 50 subjects to assess agreement and a mg/cc osteopenia threshold was established using DXA T-scores. CIREN HU measurements were converted to mg/cc using the phantomless technique and the mg/cc osteopenia threshold was used to compare vBMD to age, fracture incidence, and osteopenia comorbidity classifications in CIREN.

Results: Linear regression of lumbar vBMD derived from the qCT versus phantomless calibrations showed excellent agreement (R2 = 0.87, P <.0001). A 145 mg/cc threshold for osteopenia was established (sensitivity = 1, specificity = 0.57) and 44 CIREN occupants had vBMD below this threshold. Of these 44 occupants, 64% were not classified as osteopenic in CIREN, but vBMD suggested undiagnosed osteopenia. Age was negatively correlated with vBMD in both sexes (P <.0001) and CIREN occupants with less than 145 mg/cc vBMD sustained an average 1.7 additional rib/sternum fractures (P =.036).

Conclusions: Because lumbar vBMD was estimated from phantomless CT scans with accuracy similar to qCT, the phantomless technique can be broadly applied to both prospectively and retrospectively assess patient bone quality for research and clinical studies related to MVCs, falls, and aging.  相似文献   
487.
环保型吸附制冷中经济工质对法的实验与理论研究   总被引:2,自引:1,他引:2  
针对环保型吸附制冷的特点,提出了一种新的评价方法,并利用该法对环保型吸附制冷中的两个关键因素工质对的选择及操作条件的优化进行了实验研究和理论分析,得出了一些有价值的结论,为环保型吸附制冷的应用提供了理论依据.  相似文献   
488.
通过对敖其村地表水、饮用水源地、环境空气、土壤进行调查,发现作物种类改变、监测点位变化、专业人员匮乏、经费来源紧张等问题制约了农村环境质量监测工作的开展,建立固定监测点位、加强人员培训、加大经费投入等措施可以有效解决农村环境质量监测中存在的问题,保证监测工作的顺利开展和进行。  相似文献   
489.
In agriculture, occupational injuries are common, and several of them lead to permanent physical disability. The objective of this case study was to assess the strain and the ergonomic needs of four farmers (aged 34–49 years) with physical disabilities. A maximal bicycle ergometer test or an arm-crank test was done to assess their maximal heart rate (HR max) and maximal oxygen consumption (V02max). The strain at work was analyzed by measuring heart rate (HR), muscle activity (EMG), and the rating of perceived exertion (RPE). The farmers were interviewed as to possible and impossible work tasks and the ergonomic redesign measures taken to improve the work environment. The work tasks performed were mainly light or moderate work for the cardiorespiratory system according to mean HR (88-102 beats/min), the percentage of HR range (17–31% HRR), and the relative V02 (22–46% V02max). The mean activity of the trapezius muscles was 0.4-9% of the maximal voluntary contraction (%MVC). All the participants had work tasks they were unable to perform. They had made ergonomie redesign changes mainly to the tractor. This case study showed that some agricultural work tasks were possible for farmers with physical disabilities and that the physical strain associated with these tasks was mainly light or moderate.  相似文献   
490.
The Hybrid III 5th percentile female dummy and seven small female cadavers were instrumented and tested as out-of-position drivers in static air bag deployment tests. Tank test pressure profiles were used to characterize inflator peak pressures and pressure onset rates of two production air bags and a prototype dual-stage system prior to their use in the static deployments. In the out-of-position tests, the chest of die surrogate was positioned in direct contact with the air bag module in an effort to create a worst-case loading environment for the thorax. For the cadavers, post-test radiographs and autopsy investigations identified rib fractures as the most common injury and showed that the number of fractures correlated well with maximum chest compression. The Viscous Criteria exceeded 1.0 m/s in nearly all dummy and cadaver tests but did not correlate well with the severity level of observed cadaver injury which was largely determined by hard-tissue rather than soft-tissue trauma. Statistical analysis of the injury, severity relative to the air bag and test parameters suggests that the pressure onset rate of the inflator is more important than peak pressure in determining the severity of out-of-position injuries and should be given primary consideration in inflator depowering efforts. Statistical comparison of dummy and cadaver responses indicates acceptable biofldelity of the Hybrid III small female dummy.  相似文献   
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