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521.
Although organizational identification is founded on social identity and symbolic interactionist theories, current theories emphasize a social identity whereby organizational members categorize themselves and others based on roles and membership in an organization or work unit. In contrast symbolic interactionism, which resides in interpersonal relationships, is rarely theorized or empirically assessed in studies of organizational identification. We use survey data collected at an academic institution to explore how the strength and structure of an individual's social network both directly influences organizational identification as well as moderates the relation between social identity, or categorical, antecedents and organizational identification. Our results show that the size of an individual's network as well as the interaction between relationship strength and prestige better explain organizational identification than do antecedents based solely on categorization and social comparison processes. Thus networks of relationships, which have been a foundational but much neglected premise and process for organizational identification, are brought back into a theory of organizational identification. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
522.
Abstract: We developed a method with which to analyze a specie's response to chronic anthropogenic disturbance (CAD). We regressed density of individuals on the intensity of 3 disturbance agents (human activities, raising livestock, and land degradation) along CAD gradients to determine how much CAD is experienced by a species; whether species are ruderal (achieving maximum densities in disturbed sites); whether density declines as a result of CAD; which disturbance agents are responsible for this reduction; and the number of populations that decline as a result of CAD. We tested the method on 9 threatened Mammillaria species (Cactaceae). Seven species were ruderal. In 4 species, actual disturbance surpassed the CAD intensity in which plants achieved their maximum densities; thus, the density of those 4 species appeared to be declining. For 7 species, some populations were threatened by human activities or livestock, whereas others were favored by them. Land degradation negatively affected all species. Our results allowed us to distinguish 4 groups of species that had similar responses and thus may require different forms of management. Our method provided an estimation of the growth rate (λ) of the studied populations that was significantly correlated with λs obtained from demographic studies. The size structures of populations were consistent with the predictions of the analysis, which suggests our results are consistent and reliable. Disturbance–response analysis provides a basis for management in heavily populated areas, where conservation must be achieved along with development activities that cause CAD. The method provides readily interpretable information, which facilitates participative decision making; the data are rapidly generated, which makes it appropriate when results are required promptly or for assessment of large numbers of species; and it provides a comprehensive perception of how threatened species behave in the real world. 相似文献
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524.
基于WRF-CMAQ模型系统定量分析了气象和排放因素对全国及重点区域PM2.5污染影响程度.从年度特征来看,与2015年相比,2016年、2017年全国空气质量明显改善,PM2.5年均浓度分别下降7%和14%;2016年气象条件总体转好,气象因素和排放因素变化导致全国PM2.5年均浓度下降幅度分别为4%和3%;2017年全国气象条件与2015年相比基本持平,大气污染物排放量下降是PM2.5污染减轻的决定因素.除汾渭平原外,京津冀及周边地区"2+26"城市、长三角、成渝地区空气中的PM2.5年均浓度持续下降;珠三角气象条件变化对PM2.5影响较大,2017年导致PM2.5浓度上升了29%;除汾渭平原外,其他4个重点地区的污染物排放变化导致PM2.5年均浓度下降且2017年的下降幅度进一步加大,说明污染管控措施的环境效益明显.从季节特征来看,气象影响值的区域性差异明显.本文分析方法可用于制定空气质量目标或者评估污染控制方案的环境效果. 相似文献
525.
纳污河流抗性基因和微生物群落相关性 总被引:2,自引:0,他引:2
通过Miseq高通量测序分析和荧光定量PCR技术,研究某纳污河流中四环素类与磺胺类抗性基因(ARGs)的分布特征、传播情况及微生物群落结构相关性.结果表明:在河流地表水与沉积物中均检测到四环素类抗性基因tetA和tetB与磺胺类抗性基因sul1和sul2,四环素类抗性基因和磺胺类抗性基因的绝对丰度分别为5.09×103~1.26×107,3.94×105~1.32×109copics/L,磺胺sul1抗生素抗性基因丰度显著高于其它基因;河流主要优势菌门为Proteobacteria,Bacteroidetes,Firmicutes,Actinobacteria和Cyanobacteria,其平均总相对丰度占总比例的95.62%,且总体差异较小.抗性基因与微生物群落冗余分析显示,Methylotenera菌属是影响tetA抗性基因分布丰度的主要因素,Dechloromonas和Clostridium sensu stricto 1菌属是影响tetB抗性基因分布丰度的主要因素,Dechloromonas、Clostridium sensu stricto 1和Methylotenera菌属是影响sul1、sul2抗性基因分布丰度的主要因素. 相似文献
526.
王昱祺 《安全.健康和环境》2021,21(4):48-53
针对企业管理层安全领导力评估客观性、准确性不足的问题,通过借鉴优秀做法,分析岗位职责要求,采用半结构化(BEI)企业实地访谈及内容分析技术等,初步构建安全领导力评估指标体系,并对其进行验证优化,最终确定指标体系包括7个维度的关键要素及30个子要素。应用在某企业,结果显示:评估系统可实现安全领导力评估的量化分级和趋势分析,有助于找出管理者实际水平与指标体系要求之间的差距,为企业安全管理水平提升提供科学依据。 相似文献
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528.
上海市中心城区公园绿地对居住区的社会服务功能定量分析 总被引:1,自引:0,他引:1
城市公园绿地的社会服务功能是城市绿地系统生态服务功能的重要组成;评价其社会服务功能需同时考虑服务的公平性和有效性。为科学合理的定量分析城市公园绿地的部分社会服务功能,建立了一套评价体系,包括公园绿地服务范围覆盖率、公园绿地服务重叠度和单位面积公园绿地服务人口数等3项指标。以上海市中心城区为例,介绍了3项指标的定义;基于地理信息系统平台实现了计算流程,并对上海市中心城区主要公园绿地对于居住区的社会服务功能进行了定量分析。研究表明:2009年上海市中心城区的主要公园绿地对于居住区的服务范围覆盖率已超过80%,服务重叠度平均值为221,单位面积公园绿地服务人口数的平均值为117人/m2。3项指标可为城市公园绿地的社会服务功能分析提供有效的定量研究手段 相似文献
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530.
Emma-Christin Lönnroth Houshang Shahnavaz 《International journal of occupational safety and ergonomics》2013,19(1):49-59
Eye infections are common among dentists and many are concerned, but few are using proper eye protection. To understand users’ demands behind the low use of safety glasses, all dental teams in Sweden were asked which factors they found most important when choosing dental safety glasses, and rate the importance of 31 statements regarding ergonomic aspects of dental safety glasses in a questionnaire. Data were analysed using the Grounded Theory and a quantitative approach. Results showed that dentists ranked the visual aspects as most important and chair assistants the protective aspects. The highly visual demanding work performed by dentists requires safety glasses that are not yet available on the market, which might explain the low use. 相似文献