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71.
ABSTRACT

Press credentialing practices are a vital, yet understudied site of scholarly research on journalistic norms and practices. Press credentialing not only structures internal professional hierarchies, but they also signify the boundaries of the journalistic field itself. This paper explores the legal and theoretical implications of press credentialing to cover the United States Congress, drawing on the concepts of boundary work and journalistic authority to demonstrate the material impact of the space between fields on professional legitimation in journalism. Using WorldNetDaily (WND) as a case study, I argue that the Standing Committee of Correspondents (SCC) occupies a hybrid boundary zone between the journalistic and political fields, generating a unique tension in First Amendment jurisprudence that places journalists in a paradoxical role as both the professional embodiments of free speech and its constitutional steward. The resulting jurisdictional conflict between the SCC and WND extends the relational model of journalistic authority by articulating how journalist-state relations can fundamentally augment the process of legitimation at its fuzzy boundaries. The relevance and implications for press credentialing practices in the digital age are discussed.  相似文献   
72.
电磁波/光传输特性研究中常用TE/TM偏振描述波的传播模式.不同系统中对TE/TM偏振的定义却存在差别,有时还与s/p态混合使用,使研究者在理论和实验研究中产生概念混淆和结果矛盾的问题.本文从电磁理论出发,对传导系统中可能存在的偏振模式进行深入的推导和分析,解释TE/TM偏振态存在原因和可能状态,对其与s/p态的区别进行比较说明.针对空间偏振态的易混淆问题进行逐一解答.  相似文献   
73.
ABSTRACT

This essay reads the Latina/o/x migrant vernacular discourses that emerge out of pro-migrant activism. Anzaldúa’s notion of mestizaje – a logic of border consciousness – is put into conversation with Deleuze’s notion of nomad thought – a logic of movement – to inform a rhetorical strategy for reading the vernacular archive of social movement discourse. The “No Papers, No Fear” is one such social movement that demonstrate the logic of mestizaje/nomadism in their communication strategies. This study illuminates three tensions that define the ways Latina/o/x migrants in the US navigate the spaces of citizenship: tensions between movement/stasis, migrant identity/national identity, and fear/safety.  相似文献   
74.
In fall 2016, the Columbia-Cornell collaboration in the area of Slavic & East European resource coordination and sharing celebrated its sixth year. The author reviews particulars of the development, implementation, and function of this program as well as some of the challenges that face such cross-institutional efforts.  相似文献   
75.
目的:应用ActiGraph GT3X对网球运动等非周期性运动能量消耗进行测评,建立适合网球运动能耗预测的回归方程,从而丰富ActiGraph测量体系.方法:以K4b2测量值作为校标,分别在拍柄、持拍手手腕外侧、腰部髂肌外侧、大腿中央前侧和脚踝外侧(持拍手同一侧肢体)各佩戴一个加速度计(ActiGraph GT3X),同步对网球运动中不同球速下(30 km/h、60 km/h)的原地正、反手击球,侧向移动正、反手击球,向前移动正、反手击球,侧向移动正反手交替击球和模拟自由单打的运动过程进行监测.结果:腰部、大腿和踝关节部位GT3X的EE和MET预测值存在明显低估,与K4b2测量值一致性较低;手腕和拍柄部位GT3X的EE和MET预测值存在明显高估,与K4b2测量值一致性较低;研究建立了2个网球运动能耗预测回归方程,经检验其预测值与实测值没有显著性差异.结论:运用ActiGraph GT3X对网球等隔网对抗运动项目进行监测存在显著误差,EE和MET的预测存在明显高估或低估的现象;基于ActiGraph GT3X所建立的能耗预测方程能对网球运动进行有效的运动监测.  相似文献   
76.
以中国南海东岛周边海域为研究区域,利用波段组合法开展高分辨WorldView-2影像的水深探测能力研究,分别建立单波段、双波段和多波段模型,进行精度评价。结果表明:多波段模型反演效果最好,双波段次之,单波段最差;各波段水深探测能力比较:绿波段 >全色波段 >蓝波段 >红波段;前视影像比后视影像的水深反演精度略高,全色波段在水深探测中具有重要作用。  相似文献   
77.
There is evidence that pupils with weak literacy skills struggle on transition to secondary school. Many experience a drop in attainment in the summer break between the two. A British government‐funded programme of rigorously designed research on boosting literacy at transition had (by 2015) found only four of 15 interventions evaluated had positive effects. This small‐scale quasi‐experimental study investigated the effectiveness of support for pupils with mild literacy difficulties on transition to secondary school. Thirty‐two pupils in three schools were involved; half received the programme. Pairs were matched on reading, spelling, age and gender. Intervention was designed around the individual needs of each pupil, focusing variously on language skills, writing, reading and spelling. The group receiving the programme made modest gains in spelling, reading efficiency and single word reading. The comparison group lost ground, relatively, in all three areas. The results suggest a promising line for more rigorous investigation.  相似文献   
78.
《Literacy》2017,51(1):44-52
This paper reports on some data on the effects of screen‐based interactivity on children's engagement with storybook apps during family shared book reading that were gathered in a 2‐year, small‐scale ethnographic case study in Spain. Data analysis focuses on the complex interplay between the storybook app's interactive features and the children's responses to them. Our findings show that interactive elements increase the child's autonomy, as they tend to promote the importance of the reader, positioning him or her as a collaborator, storyteller, an author or an internal character in the fiction; something that can materialise in exciting narrative strategies that can trigger powerful responses to digital literary texts in emergent readers, including playing, creating new fictions or engaging emotionally with the story. Finally, we argue that the Reader Response models that have been used over recent decades to understand children's reading experiences with storybooks need to be revised to better understand their current experiences with interactive texts.  相似文献   
79.
目的::通过观察一次性大负荷游泳运动后线粒体形态结构以及线粒体融合分裂基因及蛋白表达的动态变化,探讨一次性大负荷游泳运动引起大鼠额叶神经元凋亡发生发展的可能机制。方法:72只雄性SD大鼠随机分为对照组(C组,n=18),一次性大负荷游泳运动组(E组,n=54),再根据运动后取材时间的不同将 E组分为:即刻组(E0组,n=18);24h组(E24组,n=18);48h组(E48组,n=18)。 C组常规饲养,E组进行一次性大负荷游泳运动,无负重游泳4小时。用透射电镜观察额叶神经元及神经元线粒体的形态结构;用TUNEL法检测细胞凋亡指数( AI);检测线粒体融合分裂基因Drp1、Mfn2 mRNA转录及蛋白表达水平。结果:检测发现E组大鼠大脑额叶神经元发生了细胞凋亡,E组各组大鼠AI显著性高于C组(P<0.01),E组各时间点AI比较为:E24>E0> E48,各组间差异均具有显著性( P<0.05)。一次性大负荷运动后各时间点Drp1和Mfn2 mRNA转录和蛋白表达均高于C组( P<0.05),其中E24组大鼠大脑额叶Drp1和Mfn2 mRNA转录和蛋白的表达最强(P<0.01);与E24组比较,E48组大鼠大脑额叶Drp1 mRNA转录和蛋白的表达下调显著(P<0.05),而Mfn2 mRNA转录和蛋白的表达下调不明显(P>0.05)。结论:一次性大负荷游泳运动引起大鼠额叶神经元凋亡及神经元线粒体形态结构异常,该异常在运动后48h内呈现动态性变化,机体可能通过调节线粒体融合分裂基因Drp1、Mfn2表达,影响大鼠额叶线粒体的形态结构和功能,从而调控额叶神经元凋亡的发生和发展。  相似文献   
80.
2005年开始,国内兴起非金融机构经营互联网金融业务的热潮。非金融机构提供在线互联网金融服务,经营业务主要包括“支付”与“投、融资”两大类,其形态主要有四:第三方支付、基金销售、P2P网络借贷,以及众筹。非金融机构经营互联网金融,虽可加快国内金融业转型的步伐,并满足中小企业及个人无法自银行取得资金的投、融资需求,但也因发展过速,监管不足,致使网络借贷倒闭事件频传,不利于金融稳定等诸多负面效应。为此,需要主管机关研究制定与互联网金融相关的法律,加强监管,并准许这些非金融机构转型为正规商业银行。  相似文献   
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