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Lauri Haapanen 《Journalism Practice》2020,14(3):374-394
ABSTRACTThe Mediated Social Communication (MSC) approach considers mass media a venue for opposing and complementary societal groups to publicly negotiate socially relevant topics. This negotiation is conducted through representatives of these groups and mediated by journalists. Inspired by the MSC approach, this paper presents an empirically grounded model that structures the mediating process through the process of quoting. By identifying the key phases of newswriting as sub-processes of quoting, the paper argues that journalists (1) decide on a topical issue to be addressed (topicalisation), (2) identify groups of people who are linked to this issue (societal localisation), (3) pick some people as representatives of these societal groups (personalisation), and (4) verbalise these people's points of view, often by means of quoting, inter alia (verbalisation). The four-phase model is then operationalised into a data collection method that facilitates access to and fosters new insights into the subtle dynamics of newswriting. Hitherto, these dynamics have often remained obscure, because the craft ethos is adopted as tacit knowledge through implicit socialisation and is therefore difficult for journalists to verbalise. The paper concludes by calling for reconsideration of journalists’ role as gatekeepers who decide which issues and voices are heard in public discourse. 相似文献
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Eric R. Muoz Jaclyn B. Caccese Brittany E. Wilson Kyle T. Shuler Fernando V. Santos Carolina T. Cabn John J. Jeka Dianne Langford Matthew B. Hudson 《运动与健康科学(英文)》2021,10(2):122
BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease. 相似文献
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Although video clubs have been used to support (student) teachers' learning through reflection upon practice, less attention has been paid to their potential use for supporting changes in participants' practice over a period of time. Prior work has also largely treated (student) teachers as an undifferentiated whole that benefits in similar ways from video clubs. In this study, we problematize this assumption by drawing on three cases of student teachers to exemplify three different learning paths while participating in a video club during field placement. Reflecting on these findings, we discuss implications for differentiating the video-club approach to address different student teachers. 相似文献
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AbstractIn recent years, volunteering has received strong research attention from both scholars and practitioners. For the most part, involvement in volunteer activities has been identified as an important determinant of future volunteering. Through revalidating an existing instrument, the purpose of this study was to assess the dimensions of volunteer satisfaction at the 2012 London Olympic Games and its impact on future volunteer behaviour. The findings of this study shed light on the identification of volunteer satisfaction factors in the mega sporting event setting, particularly for a unique type of volunteer (i.e. media worker) assigned to a special set of tasks. Unlike Galindo-Kuhn and Guzley’s results that revealed participation efficacy and group integration to be strong predictors of volunteer satisfaction, organizational support was the primary predictor for media centre volunteers’ re-participation intention towards future volunteering programmes. 相似文献
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[目的/意义]老年教师的使用意愿不高严重影响了高校图书馆微信公众平台的发展与进步,因此需要研究高校图书馆微信公众平台的老年教师使用意愿影响因素。[方法/过程]对科技接受模型进行改进与扩展,基于结构方程,引入性别、年龄与经验等调节因素,搭建老年教师高校图书馆微信公众平台使用意愿模型,并基于四川高校的调研数据对模型与假设进行检验与分析。[结果/结论]研究结果表明:从整体来看,该模型对老年教师高校图书馆微信公众号使用意愿的总体解释效果良好;从各个影响因素来看:实用性感知以及群体影响对老年教师高校图书馆微信公众号使用意愿具有显著的正面影响,而生理机能显著反向影响其使用意愿。 相似文献
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ABSTRACTThis article explores the current state of Occupational Social Work/Employee Assistance (OSW/EA) education. It examines the relationship between social work curricula, field placement experiences, and entry-level employment opportunities in the OSW/EA field. It is based on an educational initiative called the Partnership for Employee Assistance Education. Drawing on the OSW/EA literature, surveys, and focus group materials, the article concludes that the nature of OSW/EA is being reshaped by information technology, shifting demographics, globalization, and evolving terms and conditions of employment. The authors discuss how the graduate-level OSW/EA curriculum and field placements are being transformed to reflect these trends. Concepts such as Organizational Social Work and organizational intelligence are discussed. Innovative educational strategies are recommended. Finally, the authors argue that the contemporary workplace offers potential opportunity for innovative social work practice and education. 相似文献
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基于新鲜度和配送成本的易腐食品配送路径 总被引:1,自引:0,他引:1
为解决企业在制定易腐食品配送计划时难以权衡配送总成本与交付产品的新鲜度的问题,建立以配送总成本最低和交付产品平均新鲜度最大为目标,带时间窗的易腐食品配送路径规划模型。采用自适应差分进化(differential evolution,DE)算法求解模型,通过数值算例验证模型和算法的有效性。与基本DE算法和基本蚁群算法的求解结果进行对比,自适应DE算法的求解结果更优,收敛速度更快。求得的帕累托解集表明配送总成本与交付产品平均新鲜度相悖,增加少量的配送成本可以使交付产品的平均新鲜度得到大幅提升。对易腐食品保质期、时间窗宽度和车辆装载量进行灵敏度分析,为企业在不同配送情景下在配送总成本与交付产品的平均新鲜度之间的权衡提供参考。 相似文献
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[目的/意义]探讨工作资源对高校图书馆员敬业度的影响与机制,以期为高校图书馆实施人力资源管理和提升图书馆员的敬业度提供参考。[方法/过程]选取湖南各高校图书馆的358名馆员为研究对象,考察工作资源对高校图书馆员敬业度的预测作用以及心理资本与组织承诺在两者之间的中介作用。[结果/结论]描述性统计与差异分析、相关分析和逐步回归分析的结果表明,不同性别的高校图书馆员在组织承诺量表得分上存在显著性差异,男性馆员组织承诺得分显著高于女性,不同性别馆员在其余得分上均不存在显著性差异。不同婚姻、年龄、学历、职位、职称者在各量表得分上均不存在显著性差异。高校图书馆员工作资源、心理资本、组织承诺与敬业度的两两相关都达到统计显著性水平。工作资源对高校图书馆员的敬业度具有正向预测作用,心理资本和组织承诺能够在工作资源对高校图书馆员敬业度的影响中起部分中介作用。丰富高校图书馆员工作资源,增进其组织支持感,增强其心理资本和组织承诺,是促进高校图书馆员敬业度提升的有效路径。 相似文献
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为提高自动化集装箱码头自动导引小车(automated guided vehicle,AGV)作业效率和利用率,考虑AGV的电量续航能力和重空载的耗电差异,在AGV任务选择时综合考虑任务距离和各任务紧急程度,并设置AGV充电结束条件以减少AGV排队等待的时间,建立以最小化完成任务总时间为目标的AGV调度模型。用Java进行实例求解。结果表明,对AGV采用多频次充电并将其允许工作电量百分比设定为71%时,完成任务总时间最短,耗电量最小,且AGV利用率较高。 相似文献