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排序方式: 共有1619条查询结果,搜索用时 15 毫秒
701.
The main objective of this article is to determine key factors that may have a significant effect on the verbal abuse, emotional abuse and physical assault of health care workers in north-eastern Turkey. A self-administered survey was completed by 450 health care workers in three well-established hospitals in Erzurum, Turkey. Because of the discrete and ordered nature of the dependent variable of the survey, the data were analysed using four distinctive ordered response models. Results revealed that several key variables were found to be a significant determinant of workplace violence, such as the type of health institution, occupational position, weekly working hours, weekly shift hours, number of daily patient contacts, age group of the respondents, experience in the health sector, training against workplace violence and current policies of the hospitals and the Turkish Ministry of Health.  相似文献   
702.
This study sought to determine if spatiotemporal skills, represented by success in high level sport, transfer to driving and, if so, whether such transfer is mediated by the gender of the driver. Using an emergency-braking test, we compared the driving ability of male and female athletes and non-athletes and showed that athletes achieved significantly longer and therefore superior durations for time-to-contact. The advantage of athletic participation thus did not appear in movement time but rather in the ability to produce desirable performance in context. We found that males and females did not differ significantly with respect to driving, however, involvement in sport apparently transfers to aspects of driving and so provides benefits beyond the intrinsic reward of the sports activities themselves.  相似文献   
703.
近些年,境外中资企业员工遭遇武装袭击、绑架劫持事件屡有发生,如何加强境外公共安全管理,有效保障企业员工生命和设备财产安全成为了所有走向海外企业必须面对的一道严峻课题.以2012年3月26日中资公司施工队应对北南苏丹边界1/2/4油区爆发的军事冲突事件为例,详细描述了该中资公司队伍紧急避险和快速撤离的过程,对应急行动成功的经验进行了分析和总结,并进一步提出做好境外公共安全管理工作的重点.案例不但为境外中资企业应对和处置境外公共安全突发事件提供了样板,更为广大境外中资企业强化境外公共安全管理提供了借鉴和参考.  相似文献   
704.
以安全生产相对指标工矿商贸十万就业人员生产安全事故死亡率为研究对象,通过文献调研分析,最终从经济发展、经济发展结构、经济活动水平和社会活动水平角度筛选出14个指标为观察对象,采用逐步多元回归分析法筛选出影响我国安全生产的主要经济社会发展指标为:第三产业增加值产值占GDP比重、第三产业就业人数占总就业人数的比重和固定资产投资增长速度,并建立了回归模型。应用弹性系数法对主要影响因素进行重要性排序,并推测工矿商贸就业人员十万人事故死亡率将保持持续下降的趋势。  相似文献   
705.
为准确高效地开展地铁车站暴雨内涝应急响应活动,增强应对暴雨内涝灾害的救援能力,采用SHEL系统模型识别响应效能影响因素,分析各影响因素之间的相互作用机制,研究如何协调各个因素的投入比例,以达到响应效能最优,利用Vensim软件,结合成都地铁11号线相关数据进行模拟仿真。研究结果表明:应急响应活动存在明显阶段性特征,应急响应活动前期应保证救援人员快速到场,中期应特别注重提高救援指挥机构决策效率,后期更应关注硬件配置,且在应急响应活动全过程中持续保证人员与其他各界面的动态匹配。研究结果可为应对暴雨内涝灾害提供参考。  相似文献   
706.
● A cellphone-based colorimetric multi-channel sensor for in-field detection. ● A universal colorimetric detection platform in the absorbance range of 400–700 nm. ● Six-fold improvement of sensitivity by introducing a transmission grating. ● Quantifying multiple water quality indexes simultaneously with high stability. The development of colorimetric analysis technologies for the commercial cellphone platform has attracted great attention in environmental monitoring due to the low cost, high versatility, easy miniaturization, and widespread ownership of cellphones. This work demonstrates a cellphone-based colorimetric multi-channel sensor for quantifying multiple environmental contaminants simultaneously with high sensitivity and stability. To improve the sensitivity of the sensor, a delicate optical path system was created by using a diffraction grating to split six white beams transmitting through the multiple colored samples, which allows the cellphone CMOS camera to capture the diffracted light for image analysis. The proposed sensor is a universal colorimetric detection platform for a variety of environmental contaminants with the colorimetry assay in the range of 400–700 nm. By introducing the diffraction grating for splitting light, the sensitivity was improved by over six folds compared with a system that directly photographed transmitted light. As a successful proof-of-concept, the sensor was used to detect turbidity, orthophosphate, ammonia nitrogen and three heavy metals simultaneously with high sensitivity (turbidity: detection limit of 1.3 NTU, linear range of 5–400 NTU; ammonia nitrogen: 0.014 mg/L, 0.05–5 mg/L; orthophosphate: 0.028 mg/L, 0.1–10 mg/L; Cr (VI): 0.0069 mg/L, 0.01–0.5 mg/L; Fe: 0.025 mg/L, 0.1–2 mg/L; Zn: 0.032 mg/L, 0.05–2 mg/L) and reliability (relative standard deviations of six parallel measurements of 0.37%–1.60% and recoveries of 95.5%–106.0% in surface water). The miniature sensor demonstrated in-field sensing ability in environmental monitoring, which can be extended to point-of-care diagnosis and food safety control.  相似文献   
707.
土壤微生物呼吸热适应性被认为是决定陆地生态系统对全球变暖反馈作用的潜在重要机制,可能显著改变未来的气候变化趋势,然而,土壤微生物群落结构变化如何引起土壤微生物呼吸热适应性的研究目前尚存争议.该文针对气候变化对土壤微生物呼吸的影响研究,梳理了当前对土壤微生物呼吸的热适应性是否存在的争议和不同观点与结论,综述了气候变化对土...  相似文献   
708.
Adaptation options in agriculture to climate change: a typology   总被引:9,自引:0,他引:9  
Adaptation in agriculture to climate change is important for impact andvulnerability assessment and for the development of climate change policy. A wide variety of adaptation options has been proposed as having thepotential to reduce vulnerability of agricultural systems to risks related toclimate change, often in an ad hoc fashion. This paper develops atypology of adaptation to systematically classify and characterize agriculturaladaptation options to climate change, drawing primarily on the Canadiansituation. In particular, it differentiates adaptation options in agricultureaccording to the involvement of different agents (producers, industries,governments); the intent, timing and duration of employment of theadaptation; the form and type of the adaptive measure; and the relationshipto processes already in place to cope with risks associated with climatestresses. A synthesis of research on adaptation options in Canadianagriculture identifies four main categories: (i) technological developments,(ii) government programs and insurance, (iii) farm production practices,and (iv) farm financial management. In addition to these `directadaptations', there are options, particularly information provision, that maystimulate adaptation initiatives. The results reveal that most adaptationoptions are modifications to on-going farm practices and public policydecision-making processes with respect to a suite of changing climatic(including variability and extremes) and non-climatic conditions (political,economic and social). For progress on implementing adaptations to climatechange in agriculture there is a need to better understand the relationshipbetween potential adaptation options and existing farm-level andgovernment decision-making processes and risk management frameworks.  相似文献   
709.
Least flycatchers (Empidonax minimus) and American redstarts (Setophaga ruticilla) overlap in the use of food resources on their breeding grounds, promoting high levels of interspecific aggression by the socially dominant flycatcher. We examined the role of song in this interspecific aggression by using repeated-measures-designed playback experiments and observational data on induced aggressive interactions. Flycatchers were more likely to approach the speaker during presentation of redstart song than during intervals of no song or presentation of control song. Approach was close enough to enable visual contact with a singing redstart. In contrast, redstarts made significantly fewer flights following presentation of flycatcher song, when risk of flycatcher attack may be greatest. Reducing the number of flights likely reduces the risk of flycatcher attack on the redstart, as flycatchers do not attack stationary redstart models and are apparently dependent on cues from redstart flight for visual heterospecific recognition. Flycatcher-specific responses of redstarts and marked differences in song morphology rule out misdirected intraspecific aggression as a proximate or ultimate cause of interspecific response to song. Results indicate that song is an important component in aggressive interactions between these two species, and reflect the dominant role of the flycatcher in such interactions. Our results also illustrate the capacity for interspecific interference competition to influence behavior and heterospecific song recognition in two distant avian taxa. Received: 10 January 1995/Accepted after revision: 8 June 1996  相似文献   
710.
以武汉市2000~2013年数据为基础,构建了城市化综合水平和空气环境综合指数的评价指标体系,利用结构熵权法和响应度模型对城市化进程中的空气环境响应时序特征和整体响应强度进行了比较分析。结果表明:(1)2000年后武汉市城市化呈现快速增长态势,进入了一个快速增长时期;空气环境综合指数及其分量呈现不同的变化特征,综合指数呈波动中递增趋势;(2)空气环境综合指数及其分量对城市化有着不同的响应特征,其中,空气质量指数与综合指数由正响应转向负响应,2010年为拐点,表明近年来,武汉市空气环境压力变大,空气质量有恶化的趋势;(3)相同城市化进程中,空气环境质量的正向响应相对于空气负荷压力的减小具有不一致性和滞后性,2013年后的武汉市空气质量需要持久努力改善。城市空气环境质量改善是一个漫长的过程,需要在减小空气污染排放的压力同时,调整产业结构、节能减排,并要积极预防城市化扩张过程中的建设施工、道路、裸露地面等扬尘污染。  相似文献   
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