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排序方式: 共有2135条查询结果,搜索用时 15 毫秒
1.
"互联网+教育"的发展已衍生出了一系列教育教学创新方法,对高等职业教育发展产生了诸多影响,是提升高等职业教育实效的重要路径。基于慕课对高等职业教育的影响进行分析,就该视角下的高等职业教育发展进行探究。  相似文献   
2.
在课堂教学中发现,学生难以理解在被冲击物的水平方向上施加冲击物的重力来计算动荷因数。本文研究了不同水平静荷载的施加对冲击问题的影响,推导出水平冲击问题求解的通用公式,证明水平冲击问题与静荷载的施加方式及大小无关。若采用动荷因数法,需选择冲击物自身重力作为被冲击物的水平静载,才可得到教材中的结果。结合国外材料力学教材,介绍了水平冲击问题的另一种求解方法,拓宽了读者求解水平冲击的思路,并给出相应的教学建议。  相似文献   
3.
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   
4.
ABSTRACT

Research impact features heavily in debates about ‘the measured university’ and is now formally assessed by governments in the UK and Australia. Yet clear guidance on how impact can be measured in non-monetary ways is often lacking because of confused thinking and the context-specific nature of outcomes. To help resolve this, we first propose a general impact model of inputs, processes, outputs and outcomes framework. Then, using a survey approach of research users, we measure outcomes at different levels of abstraction using usefulness as the central construct and impact categories from the European (EU) and Association to Advance Collegiate Schools of Business (AACSB). The survey measures are simple, comparable between different impact cases, cost-effective, externally verifiable, and easily administered by those for whom impact measurement is new and puzzling. They can also be combined to form an impact index to address criticism that there is little standardisation in impact measurement. To improve the standardisation of context-specific measures, we suggest a common methodology for deriving these (SROI). The article discusses limitations of using surveys including administration, self-report data, and impact timescale problems, and suggests ways to reduce these. Implications for researchers, research managers, and assessors interested in measuring impact, such as who should do it and pay for it, are discussed.  相似文献   
5.
《Journal of Informetrics》2019,13(2):485-499
With the growing number of published scientific papers world-wide, the need to evaluation and quality assessment methods for research papers is increasing. Scientific fields such as scientometrics, informetrics, and bibliometrics establish quantified analysis methods and measurements for evaluating scientific papers. In this area, an important problem is to predict the future influence of a published paper. Particularly, early discrimination between influential papers and insignificant papers may find important applications. In this regard, one of the most important metrics is the number of citations to the paper, since this metric is widely utilized in the evaluation of scientific publications and moreover, it serves as the basis for many other metrics such as h-index. In this paper, we propose a novel method for predicting long-term citations of a paper based on the number of its citations in the first few years after publication. In order to train a citation count prediction model, we employed artificial neural network which is a powerful machine learning tool with recently growing applications in many domains including image and text processing. The empirical experiments show that our proposed method outperforms state-of-the-art methods with respect to the prediction accuracy in both yearly and total prediction of the number of citations.  相似文献   
6.
谭智敏  刘万国 《现代情报》2019,39(3):150-156
随着"双一流"建设总体方案的提出,科研成果越来越受到重视,高校图书馆开展学科评价服务,对于提升图书馆的服务和地位具有至关重要的意义。本文在分析了吉林大学2010-2016年发表的论文总体情况的基础上,选取论文发表总量前10名的学科为研究对象,运用文献计量学方法和马尔可夫模型分析方法,与传统的评价指标相结合,构建相应的综合评价指标,消除学科间的基础差异,分析得出各个学科的发展速度和发展趋势情况。  相似文献   
7.
【目的】 探讨我国英文科技期刊微信公众号运营的思路,以提升我国英文科技期刊影响力。【方法】 采取个案研究法,总结我国英文科技期刊微信公众号的设计策略。【结果】 “药学学报”微信公众号通过宣传推广文章和构建期刊社群,成功地辅助《药学学报(英文版)》全面提升了影响力。【结论】 我国英文科技期刊微信公众号可围绕宣传期刊文章,以及运营由作者、编委、读者构成的期刊社群,以宣传期刊品牌,全面提升期刊影响力。  相似文献   
8.
Traditionally, citation count has served as the main evaluation measure for a paper's importance and influence. In turn, many evaluations of authors, institutions and journals are based on aggregations upon papers (e.g. h-index). In this work, we explore measures defined on the citation graph that offer a more intuitive insight into the impact of a paper than the superficial count of citations. Our main argument is focused on the identification of influence as an expression of the citation density in the subgraph of citations built for each paper. We propose two measures that capitalize on the notion of density providing researchers alternative evaluations of their work. While the general idea of impact for a paper can be viewed as how many researchers have shown interest to a piece of work, the proposed measures are based on the hypothesis that a piece of work may have influenced some papers even if they do not contain references to that piece of work. The proposed measures are also extended to researchers and journals.  相似文献   
9.
再制造品环境税征收政策研究   总被引:1,自引:0,他引:1       下载免费PDF全文
王哲  李帮义  王玥 《科研管理》2019,40(2):186-198
虽然再制造品减少了对能源和材料的需求,但是生产和使用再制造品依然会带来环境问题,而且当其蚕食效应达到一定程度时将会导致环境效益变坏,因此是否应该对再制造品征税受到了人们的关注。为了更好的分析引入再制造品征税对供应链生产决策、环境、经济和社会福利的影响,分别构建了有无再制造征税情况下包含政府和制造商的二阶段Stackelberg博弈模型,利用逆向归纳法求解分析发现:对再制造品征税会导致政府可调控税收范围变小;低税收政策下引入再制造品征税可以促进制造商新产品生产销售行为,高税收政策下将阻碍制造商生产销售行为。引入再制造品征税后,高税收政策下制造商会出现经济效益变坏、环境效益变好的“一输一赢”局面,低税收政策下一定条件下会出现经济和环境效益都变坏的“双输”局面。所以,当制造商税收负担较低且消费者环保意识高于再制造品环境影响时,规制者不应当对再制造品征税。为了更好衡量立法有效性,政府应当平衡经济、环境和社会效益,以福利最大化为标准决定是否对再制造品进行征税,并确定最优税收水平。最后,通过算例分析给出了相关结论的验证,并获得了一些新的管理启示。  相似文献   
10.
[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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