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1.
习近平总书记在2016年"科技三会"上发出建设世界科技强国的号召。建设世界科技强国不仅需要资源要素的支撑,更需要有将这些要素进行合理配置的制度安排,需要新的模式来激发新的创造力。其中,对评价制度的改革在寻找科技体制新模式的改革关键举措中具有基础性作用。为此,回顾过去,文章从科技体制与科技评价的关系视角重新审视这一问题,从回归科技评价的本源出发,探究科技评价异化的体制问题。相应地,面向未来,文章从改革主线、改革结构、评价体系3个方面提出推动以科技创新为核心的科技体制改革建议,为建成百年科技强国提供政策依据。  相似文献   
2.
ABSTRACT

It is a common fact that women's sport and leisure history, especially in male dominated spheres, and more specifically football, have been ignored by many academics. However, in recent years there have been major developments in digital technology that have changed the nature of the type of research that can be done. Access to tools to facilitate field research are relatively cheap and with the high volume of digitisation projects that have taken place over the last few years as well as the increasing number of born digital resources that have been published, there are new opportunities. In relation to women's soccer in Ireland, this paper asks the question – where are we now? The argument will review the current literature on this subject and outline potential approaches for future research.  相似文献   
3.
目的:探讨不同负荷运动训练对大鼠骨骼肌线粒体三羧酸循环的影响及其机制。方法:将雄性Wistar大鼠50只随机均分为5组:安静对照组(C)、低负荷运动训练组(LT)、中等负荷运动训练组(MT)、高负荷运动训练组(HT)和极高负荷运动训练组(ST),每组10只。各运动组分别进行6周的跑台运动训练。训练方案结束后,取腓肠肌样本,提取线粒体,测定线粒体柠檬酸合成酶(CS)、异柠檬酸脱氢酶(ICD)和α-酮戊二酸脱氢酶(α-KGDHC)活性;线粒体Ga2+含量、胞浆NADH、NAD+、ATP和ADP含量,以及ICD mRNA转录水平。结果:(1)不同负荷运动训练组线粒体CS、ICD和α-KGDHC的活性均显著高于安静对照组(P < 0.01),且CS和ICD活性由高到低顺序均为:MT组 > HT组 > ST组 > LT组 > C组,α-KGDHC活性由高到低顺序为:HT组 > MT组 > ST组 > LT组 > C组。(2)不同负荷运动训练组线粒体Ca2+ 含量均显著高于安静对照组(P < 0.01),其含量由高到低顺序为:MT组 > HT组 > ST组 > LT组 > C组;胞浆NADH/NAD+和ATP/ADP的比值均显著低于安静对照组(P < 0.01),其比值由低到高顺序为:MT组 < ST组 < HT组 < LT组 < C组。(3)不同负荷运动训练组ICD mRNA转录水平均高于安静对照组(P < 0.01),其水平由高到低顺序为: MT组 > HT组 > ST组 > LT组 > C组。结论:低负荷、中等负荷、高负荷及极高负荷运动训练均可提高大鼠骨骼肌线粒体三羧酸循环功能,且中等负荷运动训练效果最佳。其机制与胞浆NADH/NAD+和ATP/ADP比值、线粒体摄钙能力及限速酶基因的表达有关。  相似文献   
4.
利用类型Ⅱ弦理论/F理论对偶,第一次在平行和重合相区计算一个具体的双D膜系统的超势,并提取Ooguri-Vafa不变量。平行D膜相与重合D膜相间的相变也对应着D膜世界叶上规范理论规范对称性的提升U(1)×…×U(1)→U(n)。计算显示这两个相区的超势截然不同,并给出不同的Ooguri-Vafa不变量。这意味着相变的发生导致两个相区能谱结构的差异。  相似文献   
5.
Game-based learning can have a positive impact on medical education, and virtual worlds have great potential for supporting immersive online games. It is necessary to reinforce current medical students' knowledge about radiological anatomy and radiological signs. To meet this need, the objectives of this study were: to design a competition-based game in the virtual world, Second Life and to analyze the students' perceptions of Second Life and the game, as well as to analyze the medium-term retention of knowledge and the potential impact on the final grades. Ninety out of 197 (45.6%) third-year medical students voluntarily participated in an online game based on self-guided presentations and multiple-choice tests over six 6-day stages. Participants and non-participants were invited to perform an evaluation questionnaire about the experience and a post-exposure knowledge test. Participants rated the experience with mean scores equal to or higher than 8.1 on a 10-point scale, highlighting the professor (9.5 ± 1.1; mean ± SD) and the virtual environment (8.9 ± 1.1). Participants had better results in the post-exposure test than non-participants (59.0 ± 13.5 versus 45.3 ± 11.5; P < 0.001) and a lower percentage of answers left blank (6.7 ± 8.4 versus 13.1 ± 12.9; P = 0.014). Competitive game-based learning within Second Life is an effective and well-accepted means of teaching core radiological anatomy and radiological signs content to medical students. The higher medium-term outcomes obtained by participants may indicate effective learning with the game. Additionally, valuable positive perceptions about the game, the educational contents, and the potential benefit for their education were discovered among non-participants.  相似文献   
6.
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   
7.
研究旨在探讨一次不同抗阻训练方案对外周血CD4+和CD8+T淋巴细胞亚群迁移和凋亡的影响。通过实验法15名无训练经历的健康青年男性分别进行一次以促进肌肉肥大(H-RT组,方案:70%1RM,10RM,3组,组间间歇1.5 min)和以改善肌肉耐力(E-RT组,方案:60%1RM,15RM,3组,组间间歇1 min)为目的的抗阻训练方案。并于训练前、训练后即刻、训练后2 h和24 h利用流式细胞仪测定表面标志物CX3CR1和annexin V表达量检测CD4+、CD8+T淋巴细胞亚群迁移和凋亡(用阳性表达率表示)。得出以下数据:(1)CD4+T细胞在H-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率显著性升高(P<0.05)。E-RT组annexin V阳性表达率在运动后即刻降低(P<0.05),24 h显著性升高(P<0.05);CX3CR1阳性表达率仅在运动后即刻升高(P<0.05)。(2)CD8+T细胞在H-RT组和E-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率均显著性升高(P<0.05)。通过对以上数据的分析,研究得出以下结论:CD4+T淋巴细胞亚群对于急性抗阻训练的免疫反应存在运动方案依赖性。  相似文献   
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9.
Using Communication Privacy Management (CPM), this study analyzed Emergency Healthcare Providers (EHP; i.e., Emergency Room Nurses, Paramedics, Emergency Medical Technicians, etc.) frequent experience of witnessing death, the dying processes, and regular involvement at the end-of-life. Twenty interviews from across the United States offered accounts of witnessing the death of a patient, communicating with the patient’s families, coworkers, and personal networks. The first research question explored the population’s normalization of death and changed outlook of dying. This population sees death and dying in real-time and must disconnect at the moment from their emotions to do their jobs. The second research question focused on preparing patient families for death, coping with coworkers, and protecting personal networks. In communicating with patient families, EHP educates/answers questions, advocate for families to be present during life-saving procedures and offer verbal and nonverbal comfort. In talking with coworkers, EHP copes with reassuring skill competency and offering emotional social support. Lastly, in communicating with their networks, EHP struggle with discussing emotions and event details in a protective function. From these results, the benefits, and challenges of communicating about death regularly are offered through a CPM lens, and recommendations to help the general population deal with death are given.  相似文献   
10.
为了全方位地揭示中国与“一带一路”沿线国家在农业科技领域的合作发展态势,本文参考ESI提供的农业科学领域期刊和农业学科高被引文献的百分位数阈值,以Web of Science核心合集中收录的6,658篇中国与“一带一路”沿线国家在农业科学领域合作发表的论文作为数据基础,使用一系列科学计量方法及可视化分析方法,从宏观(国家)、中观(科研机构)以及微观(合作研究内容)三个层次全方位地进行科学计量和可视化分析。研究发现:从国家层面来看,中国在合作关系中占有重要的地位;从合作机构来看,属于中国的科研机构在合作中具有绝对的优势;从合作研究内容来看,不同类型的合作机构,其研究内容有较大的差别。  相似文献   
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