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51.
多溴联苯醚暴露的神经行为效应及其毒理机制   总被引:1,自引:0,他引:1  
溴代阻燃剂多溴联苯醚(PBDEs)是一类在各类环境介质、生物体和人体中均能检出的普遍存在的环境污染物。我国的主要污染源之一集中于东南部地区的电子废弃物回收场地。由于PBDEs具有结构稳定性、亲脂性和生物累积性,电子废弃物拆解回收活动对当地生态系统和居民健康存在着巨大的潜在风险。PBDEs的发育神经毒性受到研究者的极大关注,但其神经行为毒性效应和机制仍需深入研究。行为学效应既是内在神经毒性机制的外在反映,也是推测环境污染物在高级别生物学水平(如种群、群落)影响的最有力试验手段。近年来,基于视频追踪系统技术的商业行为学分析设备迅速发展,使行为学效应测试在环境毒理学领域具备极大的潜力。本文结合近年来国内外环境毒理学研究进展,回顾了PBDEs的神经行为毒性效应,包括运动行为、掠食行为和认知行为,并分析了其可能的毒理机制,最后总结了当前研究存在的问题和未来研究需要关注的重点方向。  相似文献   
52.
Background. Unsafe behavior is closely related to occupational accidents. Work pressure is one the main factors affecting employees’ behavior. The aim of the present study was to provide a path analysis model for explaining how work pressure affects safety behavior. Methods. Using a self-administered questionnaire, six variables supposed to affect safety employees’ behavior were measured. The path analysis model was constructed based on several hypotheses. The goodness of fit of the model was assessed using both absolute and comparative fit indices. Results. Work pressure was determined not to influence safety behavior directly. However, it negatively influenced other variables. Group attitude and personal attitude toward safety were the main factors mediating the effect of work pressure on safety behavior. Among the variables investigated in the present study, group attitude, personal attitude and work pressure had the strongest effects on safety behavior. Conclusion. Managers should consider that in order to improve employees’ safety behavior, work pressure should be reduced to a reasonable level, and concurrently a supportive environment, which ensures a positive group attitude toward safety, should be provided. Replication of the study is recommended.  相似文献   
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为实现人群密集场所客流安全隐患早发现,辅助管理人员早决策,人群聚集风险区早疏散,提升对灾难的预见性和主动性。在国内外人群异常聚集监测预警现状分析基础上,对比分析得出监控视频分析技术是解决人群密集场所精准预警难题较为理想的解决方案;构建以视频智能分析的人群计数、密度估计、行人追踪、活动烈度识别为核心技术的人群密集场所风险预警技术框架;将该技术框架应用到某大型商圈的商业街区,获得监控区域内的人群总数、密度分布、行人轨迹和异常活动等特征。结果表明:提出的基于视频分析的人群密集场所风险预警技术框架可为城市大型商圈、交通枢纽、大型活动场所等城市公共场所的安全管理提供参考和借鉴。  相似文献   
55.
汪俊岭  王鑫  宋磊  胡源 《火灾科学》2019,28(4):211-221
棉花是纺织业的重要原料,是人民群众生活不可或缺的必需品,同时也是我国进出口重要的商品。研究如何安全有效地进行棉花的储备具有十分重要的现实意义。棉纤维本身含有脂肪、蜡质和果胶等适合微生物生长繁殖的营养物质。在棉花储备中,高的回潮率会加速微生物的繁殖,进而产生热量。热量的累积会引起温度升高以及棉花霉变,不利于棉花的安全有效储存。因此,通过静电吸附法将安全无毒的有机锌络合物附着在棉纤维表面,研究表明,相同条件下,处理棉的霉变状况明显得到抑制。加速发霉条件下,未处理棉的相对于白纸的平均色差值为28.10,而双乙酸锌以及苯甲酸锌防霉处理棉的色差值分别为5.16和5.86,下降了81.6%和79.1%。自然发霉条件下,双乙酸锌以及苯甲酸锌防霉处理棉的色差值分别下降了53.8%和50.7%。同时研究了纯棉以及处理棉氮气下的热分解动力学,相比于未处理棉,双乙酸锌防霉处理后活化能下降了15.8%,而苯甲酸锌防霉处理后活化能下降了10.9%。此外,利用实时红外和热重红外联用技术得到了样品在热解过程中固相以及气相的裂解产物的红外谱图,发现防霉处理能一定程度上抑制棉花热解。  相似文献   
56.
Conservation marketing holds potential as a means to engage audiences with biodiversity conservation and help to address the human dimensions of biodiversity loss. Empirical evaluations of conservation marketing indicatives are growing, so we reviewed the literature on this research to inform future directions in the field. We used a systematic search strategy to identify studies that evaluated the effects of conservation marketing interventions (techniques and campaigns) on psychosocial outcomes, categorized as cognitive, affective, or behavioral. Six academic databases (Business Source Complete, Communication & Mass Media Complete, Greenfile, Proquest, Scopus, and Web of Science Core Collections), 3 gray-literature databases (BASE, Zenodo, and Google Scholar), and 2 websites (Rare and WildAid) were searched. Articles were subjected to critical appraisal to assess their methodological quality, and data were extracted from each article and analyzed using narrative synthesis. Altogether 28 studies from 26 articles were included in the review. Twenty-five studies were conducted from 2014 through 2016. Methodological quality of most studies was weak (n = 16, 57%) (moderate quality n = 8, 29%; high quality n = 4, 14%). The proportion of studies that evaluated a conservation-marketing technique (e.g., variants of texts, images, or videos) versus a campaign (e.g., community-based campaigns targeting locally relevant issues, such as unsustainable palm oil agriculture, light pollution, or wood fuel fire use) was relatively balanced. Although many studies reported statistically significant results in the intended direction, the utility of findings was limited by persistent methodological limitations, such as a lack of a comparator group, use of non-validated assessment tools, and a focus on self-reported data and subjective outcomes. Conservation marketing is clearly a nascent field of scientific enquiry that warrants further, high-quality research investigations.  相似文献   
57.
A growing literature has suggested that high performance goals can have unintended consequences within organizations as employees engage in unethical behavior to achieve outcomes associated with goal attainment. Extending research on the dark side of goal setting, we suggest that high performance goals not only create a desire to achieve a particular outcome but also alter moral reasoning processes related to goal attainment. Integrating goal-setting theory with motivated moral reasoning, we hypothesize an indirect effect of high performance goals on unethical behavior via state moral disengagement. We also examine goal commitment—which tends to amplify the relationship between high goals and performance—as a key boundary condition associated with this indirect effect. We build this conditional indirect effect model across three studies conducted in the field and the laboratory. Our results provide new insight into both when and why high goals can facilitate moral disengagement and unethical behavior within organizations.  相似文献   
58.
海岛是海洋生态系统的重要组成部分,保护海岛生态环境是推进海洋生态文明建设、保护海洋生态环境的重要方面。海岛居民是保护海岛生态环境的主体之一,研究海岛居民环境友好行为的影响因素,引导和鼓励海岛居民主动采取环境友好行为是改善海岛生态环境的有效途径。本研究在梳理国内外相关文献的基础上,对海岛居民环境友好行为的概念、类型及影响因素进行理论分析,建立包含生态管理行为、消费行为、说服行为、公民行为四个环境友好行为变量,环境态度、环境保护知识、环境经历、社会政策、行为约束五个影响因素变量在内的理论模型。结合海岛生态环境和海岛居民的特点,设计海岛居民版环境友好行为测量量表,并在长岛县进行问卷调查,运用描述性统计分析、结构方程模型分析探究海岛居民环境友好行为的影响因素及影响因素间的内在关系。研究发现:①海岛居民环境友好行为总体水平差异较大,难度较低的环境友好行为实施较好,而难度较高的实施较差;影响因素变量中,环境态度积极,环境经历丰富,环境保护知识掌握较好,相关社会政策较为不利,行为约束偏中性。②环境态度、环境经历、社会政策对海岛居民环境友好行为具有显著正向影响。③环境保护知识对环境态度具有显著正向影响,但对海岛居民环境友好行为无显著影响,存在“知易行难”现象。行为约束对海岛居民环境友好行为无显著影响。④环境经历不仅直接影响海岛居民环境友好行为,而且通过环境态度对海岛居民环境友好行为施加间接影响。基于研究结论,提出了改善海岛居民环境友好行为的对策建议。  相似文献   
59.
The study tested whether attitude towards littering mediates the relationship between personality attributes (altruism and locus of control) and responsible environmental behavior (REB) among some residents of Ibadan metropolis, Nigeria. Using multistage sampling technique, measures of each construct were administered to 1360 participants. Results reveal significant independent and joint influence of personality attributes on attitude towards littering and responsible environmental behavior, respectively. Attitude towards littering also mediates the relationship between personality characteristics and REB. These findings imply that individuals who possess certain desirable personality characteristics and who have unfavorable attitude towards littering have more tendencies to engage in pro-environmental behavior. Therefore, stakeholders who have waste management as their priority should incorporate this information when guidelines for public education and litter prevention programs are being developed. It is suggested that psychologists should be involved in designing of litter prevention strategies. This will ensure the inclusion of behavioral issues in such strategies. An integrated approach to litter prevention that combines empowerment, cognitive, social, and technical solutions is recommended as the most effective tool of tackling the litter problem among residents of Ibadan metropolis.  相似文献   
60.
陈娴  陆金  殷燕  程洁红 《环境工程学报》2014,8(9):4012-4016
焙烧-酸浸法可有效回收电镀污泥中的有价金属,而污泥的热处理特性是决定能否采用焙烧预处理的重要因素。研究了氧化焙烧和还原焙烧对污泥成分和金属浸出性的影响,并对焙烧前后的污泥进行了金属形态分析和X射线衍射(XRD)分析。结果表明,焙烧预处理实现了污泥减量和金属富集;ES1经氧化焙烧后金属浸出率接近原泥,Cu的浸出率达99%;ES2的还原焙烧效果优于氧化焙烧,特别是Cu的浸出率超过97%,XRD分析发现,还原焙烧过程中金属Cu被还原为铁铜合金;2种焙烧均造成了ES3中目标金属Ni的浸出率的降低;金属浸出性的下降与残渣态的形成有关。  相似文献   
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