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91.
The current state of the Russian Science Citation Index is analyzed. Several areas for its further development identified by long-standing active users, such as data searching, refinement, and storage; current user alerts; data input with the Science Index license; patent information; and the application programming interface (API) are investigated.  相似文献   
92.
This study examines how social comparison information provided by video game leaderboards may influence players’ retrospective judgments of autonomy, competence, and relatedness need fulfillment. Participants played a video game and were randomly assigned to receive no postgame feedback or were shown a leaderboard that placed them in the top or bottom quartile of players. Results indicate downward social comparisons increase enjoyment by increasing competence and relatedness perceptions. However, upward comparisons did not have an opposite effect, nor did either type of social comparison influence players’ autonomy perceptions. Implications for applying Self-Determination Theory to video game enjoyment in the context of social comparison feedback is discussed.  相似文献   
93.
This study extends instructional communication research on extra-class communication (ECC) by presenting an integrative analysis comparing the explanatory utility of student- and instructor-oriented reasons for student engagement in frequent ECC. Results from 495 college students suggested that student-oriented reasons, specifically the relational and functional student motives, were the only significant, positive predictors of students’ perceptions of frequent ECC engagement. Other student motives (excuse making, participation, sycophancy) and perceptions of instructor approachability did not significantly predict perceived frequency of ECC engagement.  相似文献   
94.
This study investigates the convergence of two bibliometric approaches to the measurement of interdisciplinary research: one based on analyzing disciplinary diversity in the reference list of publications, the other based on the disciplinary diversity of authors of publications. In particular we measure the variety, balance, disparity and integrated diversity index of, respectively, single-author, multi-author single-field, and multi-author multi-field publications. We find that, in general, the diversity of the reference list grows with the number of fields reflected in a paper’s authors’ list and, to a lesser extent, with the number of authors being equal the number of fields. Further, we find that when fields belonging to different disciplines are reflected in the authors’ list, the disparity in the reference list is higher than in the case of fields belonging to the same discipline. However, this general tendency varies across disciplines, and noticeable exceptions are found at individual paper level.  相似文献   
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96.
Self‐efficacy is a universal construct, but few validated measures exist for researchers in developing countries to use in assessing youths’ perceptions of their ability to achieve academic success. This study examined the cross‐cultural suitability and psychometric properties of an academic self‐efficacy scale (ASES) adapted for the Ghanaian context. ASES construct validity was assessed with a sample of 4,289 Ghanaian junior high‐school students and exploratory and confirmatory factor analysis. Invariance testing assessed the scale's measurement equivalence by gender and temporal stability of gender equivalence. The ASES is a valid, reliable one‐dimensional scale for assessing young Ghanaians’ perceptions of their academic capabilities, and it works equally well across genders. As adapted, ASES is a valid scale with utility for researchers examining predictors and effects of academic self‐efficacy. The ASES has important implications for decisions regarding investment in programs aimed at improving academic self‐efficacy of youth, both in sub‐Saharan Africa and the increasingly diverse American public schools.  相似文献   
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98.
ABSTRACT

Participation in youth sport is positively associated with physical fitness and performance. The purpose of the current study was to examine if physical fitness measures during childhood and early adolescence predicted high school sport participation. Participants included youth in the Michigan State University Motor Performance Study. Measures consisted of the endurance shuttle run, Wells sit-and-reach, jump and reach, standing long jump, agility shuttle run and 30-yard dash. Individual, generalized estimating equation models were used to estimate the association between each measure and the odds of participating in high school sport. For both sexes, the endurance shuttle run and agility shuttle run were related to sport participation. For boys only, the long jump and 30-yard dash were also associated with sport participation. Better physical fitness and performance across several dimensions in childhood, including those related to motor skills, enhanced the likelihood of sport participation in high school.  相似文献   
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100.
This article considers the dynamics and specifics of training highly qualified scientific staff (philosophy doctors and doctors of sciences) in the field of information security and data protection in a 10-year period of 2004–2013 in basic research specialties as classified by the Higher Attestation Commission (VAC) of the Ministry of Education and Science of the Russian Federation.  相似文献   
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