List of Reviewers

The aim of this study was to investigate the effects of target distance on temporal and impact force parameters that are important performance factors in taekwondo kicks. Forty-nine taekwondo athletes (age = 24.5 ± 5.9 years; mass = 79.9 ± 10.8 kg) were recruited: 13 male experts, 21 male novices, 8 female experts, and 6 female novices. Impact force, reaction time, and execution time were computed. Three-way repeated measure ANOVAs revealed significant ‘distance’ effect on impact force, reaction time, and execution time (p = 0.001). Comparisons between distance conditions revealed that taekwondo athletes kicked with higher impact force from short distance (17.6 ± 7.5 N/kg) than from long distance (13.1 ± 5.7 N/kg) (p < 0.001), had lower reaction time from short distance (498 ± 90 ms) and normal distance (521 ± 111 ms) than from long distance (602 ± 121 ms) (p < 0.001), and had lower execution time from short distance (261 ± 69 ms/m) than from normal distance (306 ± 105 ms/m) or from long distance (350 ± 106 ms/m) (p = 0.003 and p < 0.001, respectively). In conclusion, target distance affected the kick performance; as distance increases, impact force decreased and reaction time increased. Therefore, when reaction to a simple visual stimulus is needed, kicking from a long distance is not recommended, as longer time is required to respond.     

Sex differences in lower extremity stiffness and kinematics alterations during double-legged drop landings with changes in drop height

The aim of this study was to determine whether sex differences and effect of drop heights exist in stiffness alteration of the lower extremity during a landing task with a drop height increment. Twelve male participants and twelve female participants performed drop landings at two drop heights (DL40 and DL60; in cm). The leg and joint stiffnesses were calculated using a spring–mass model, and the joint angular kinematics were calculated using motion capture. Ground reaction forces (GRFs) were recorded using a force plate. The peak vertical GRF of the females was significantly increased when the drop height was raised from 40 to 60 cm. Significantly less leg and knee stiffness was observed for DL60 in females. The ankle, knee, and hip angular displacement during landing were significantly increased with drop height increment in both sexes. The knee and hip flexion angular velocities at contact were significantly greater for the 60 cm drop height relative to the 40 cm drop height in males. These sex disparities regarding the lower extremity stiffness and kinematics alterations during drop landing with a drop height increment would predispose females to lower extremity injury.     

2019年男篮世界杯总决赛的关键制胜因素探究

运用文献资料调研、数理统计对比以及秩和比综合评价法等,对2019年男子篮球世界杯中晋级总决赛的两支球队的整体实力以及攻防两端的技术运用情况进行深入分析,据此总结出高水平男篮比赛的关键制胜因素,这也为中国男篮今后更好地备战世界大赛提供一定参考和借鉴。研究结果表明:在进攻方面,出色的前场篮板拼抢能力、稳定的中远投能力和优秀的团队配合能力,在防守方面,强有力的内线封盖能力和后场篮板保护能力,以及攻防两端均衡的综合实力是高水平球队在比赛中的关键制胜因素。     

高校学报影响因子与其所属高校综合实力的相关性

根据武书连"2012中国大学综合实力排行榜"和2012年版《中国科技期刊引证报告》的数据,对综合实力排名前10位的高校(排名)和其学报影响因子按学科分别进行了统计学相关性分析,同时对全国自然科学、人文社科类高校学报影响因子与其所属高校的排名进行了统计学相关性分析。结果表明,在一定条件下高校学报的影响因子与其高校排名存在一定相关性,但总体而言,相关性不强。     

Relationship between an editor in chief's commentary publications and the impact factor of cardiovascular medicine journals

Journal impact factor (IF) inflation is suggested as a problem resulting from commentaries published by the editors in chief (EiCs) of their respective journals. However, it is unclear whether this is a systemic problem across the top thirty cardiovascular medicine journals. Therefore, the purpose of this investigation was to examine the relationship between the number of commentaries written by an EiC and their journal''s IF and Eigenfactor (Ef). Utilizing Spearman rank partial correlations controlling for length of service as the EiC, significant moderate correlations were found between the number of commentaries and the number of first-author commentaries by the EiC and the IF of their journal (r=0.568, p=0.001 and r=0.504, p=0.005; respectively). A weak but still significant correlation was found between the number of commentaries by the EiC and the Ef of their journal (r=0.431, p=0.020). The reason for these correlations is unclear, and whether the methodology used to compute the IF and Ef should be modified needs further research.     

Do altmetrics assess societal impact in a comparable way to case studies? An empirical test of the convergent validity of altmetrics based on data from the UK research excellence framework (REF)

Altmetrics have been proposed as a way to assess the societal impact of research. Although altmetrics are already in use as impact or attention metrics in different contexts, it is still not clear whether they really capture or reflect societal impact. This study is based on altmetrics, citation counts, research output and case study data from the UK Research Excellence Framework (REF), and peers’ REF assessments of research output and societal impact. We investigated the convergent validity of altmetrics by using two REF datasets: publications submitted as research output (PRO) to the REF and publications referenced in case studies (PCS). Case studies, which are intended to demonstrate societal impact, should cite the most relevant research papers. We used the MHq’ indicator for assessing impact – an indicator which has been introduced for count data with many zeros. The results of the first part of the analysis show that news media as well as mentions on Facebook, in blogs, in Wikipedia, and in policy-related documents have higher MHq’ values for PCS than for PRO. Thus, the altmetric indicators seem to have convergent validity for these data. In the second part of the analysis, altmetrics have been correlated with REF reviewers’ average scores on PCS. The negative or close to zero correlations question the convergent validity of altmetrics in that context. We suggest that they may capture a different aspect of societal impact (which can be called unknown attention) to that seen by reviewers (who are interested in the causal link between research and action in society).     

基于链接的网络计量指标与大学科研得分相关性研究

链接用于大学科研评价的研究是一个新兴的研究领域,国内的相关研究仍然很少。本文在国内外现有研究的基础上,以中国的研究型大学网站为研究对象,研究了基于链接的网络计量指标与大学科研得分之间的相关性,探讨了这些网络评价指标作为现实社会中大学科研能力评价指标的有效性和可靠性。结果发现,将外部链接限制在专门的网域后所产生的一些新的计量指标,其有效性比总外部链接的有效性可能更好。而且,来自．edu和．ac．cn这两个网域的外部链接与大学科研得分的相关性最好,因此可能是评价中国大学科研能力的最好的两个网络指标。     

医学论文质量评价的若干问题

医学论文质量评价、信息交换的传统模式正在发生变化.审稿方法有明显缺陷而改革乏力.引文分析和影响因子的使用存在争议,且偏离了正确的使用轨道.开放存取出版模式与传统审稿方法相结合或许能成为医学论文评价的一种途径,做到真正意义上的"公开,公平,公正".     

生物医学类OA期刊网络影响力评价研究

OA期刊已成为科学信息的重要载体,OA期刊网站是OA期刊的网络载体。OA期刊的网络影响力不仅是0A期刊网站影响力的集中体现,同时也是OA期刊学术质量的折射。因此文章从网络计量学角度,采用网络文献量、网页数、站内链接数、WeMl文量、网络影响因子、外总影响因子、链接数、外部链接数、IP访问量、PV页面浏览量、人均页面浏览量11个指标,对483种生物医学OA期刊的网络影响力进行了评价研究。该文为2009年第六期“医学oA期刊”专题文章之一。