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151.
Patrick B. Johnson 《Psychology in the schools》1975,12(4):402-404
This experiment examined the impact of achievement motivation on the accuracy of self-reported grades. Since subjects high in achievement motivation have a greater need for success than subjects low in achievement motivation, we predicted that they would also be more likely to overestimate the degree of their success than low need achievers. This was tested by comparing the grade point overestimations of high and low need achievers. Although there was a general tendency toward oyerestimation, this tendency, as predicted, was significantly greater for individuals high in achievement motivation. The present study considered the implications of this finding as well as the validity of the self-reported grade point average. 相似文献
152.
Xiangcheng Mi Gang Feng Yibo Hu Jian Zhang Lei Chen Richard T Corlett Alice C Hughes Stuart Pimm Bernhard Schmid Suhua Shi Jens-Christian Svenning Keping Ma 《国家科学评论(英文版)》2021,8(7):29-53
Biodiversity science in China has seen rapid growth over recent decades, ranging from baseline biodiversity studies to understanding the processes behind evolution across dynamic regions such as the Qinghai-Tibetan Plateau. We review research, including species catalogues; biodiversity monitoring; the origins, distributions, maintenance and threats to biodiversity; biodiversity-related ecosystem function and services; and species and ecosystems’ responses to global change. Next, we identify priority topics and offer suggestions and priorities for future biodiversity research in China. These priorities include (i) the ecology and biogeography of the Qinghai-Tibetan Plateau and surrounding mountains, and that of subtropical and tropical forests across China; (ii) marine and inland aquatic biodiversity; and (iii) effective conservation and management to identify and maintain synergies between biodiversity and socio-economic development to fulfil China''s vision for becoming an ecological civilization. In addition, we propose three future strategies: (i) translate advanced biodiversity science into practice for biodiversity conservation; (ii) strengthen capacity building and application of advanced technologies, including high-throughput sequencing, genomics and remote sensing; and (iii) strengthen and expand international collaborations. Based on the recent rapid progress of biodiversity research, China is well positioned to become a global leader in biodiversity research in the near future. 相似文献
153.
William J. Therrien Jonte C. Taylor John L. Hosp Erica R. Kaldenberg Jay Gorsh 《Learning disabilities research & practice》2011,26(4):188-203
Although science has received much attention as a political and educational initiative, students with learning disabilities (LD) perform significantly lower than their nondisabled peers. This meta‐analysis evaluates the effectiveness of instructional strategies in science for students with LD. Twelve studies were examined, summarized, and grouped according to the type of strategy implemented. Effect sizes (ES) were calculated for each study. Across all studies, a mean ES of .78 was obtained, indicating a moderate positive effect on students with LD science achievement. Findings also align with past reviews of inquiry‐based instruction for students with special needs, indicating that students with LD need structure within an inquiry science approach in order to be successful. Additionally, results suggest that mnemonic instruction is highly effective at increasing learning disabled students' acquisition and retention of science facts. 相似文献
154.
155.
Thomas A. C. Reydon 《Metascience》2015,24(2):259-264
156.
Leonardo S. Fortes Dalton De Lima-Junior Lenamar Fiorese José R. A. Nascimento-Júnior Arnaldo L. Mortatti Maria E. C. Ferreira 《Journal of sports sciences》2020,38(5):552-558
ABSTRACTThe objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (p < .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes. 相似文献
157.
Though there is a long tradition of band members quitting the group or taking a hiatus, the rock group as an organization to produce music continues to be both popular and economically viable. The research question addressed in this paper is whether or not it is a good idea to quit or take a hiatus from the group. We begin with a discussion of the framework for understanding why groups are formed and why they may be difficult to keep together. We then discuss differences between groups in the decade of the 1960s versus today. We argue that there is something unique about the output of the group even with the changes in the structure of contracts, compensation, and consumer focus on the artist that explain the resilience of the rock band as an organizational form within which to create music. We compare the charting success of bands that have members leave the group with the charting success of the members who left the group. We identified the groups in five representative years: 1965, 1975, 1985, 1995, and 2005. We then analyzed the entire Billboard Hot 100 charting careers of those groups and the artists who quit those groups. Our main finding is that when charting success is divided equally among members, going solo pays off—there is a clear economic rationale because solo acts have greater average charting success than the original bands they started in. The other ensuing side projects: duos, collaborations, and other groups are not as lucrative as the original bands. These findings are valid for members of charting groups from each of the 5 years examined. Despite the difficulties in keeping a rock band together, there are fewer band breakups today and remaining with the group generally results in a longer and more productive charting career. Thus, the rock group remains an important organization for producing contemporary music. However, there remains a compelling incentive to go solo. Superstars may benefit from solo projects, but for the average, non-superstar group member, in many circumstances it is better for the band to stay together if the income is divided equally. 相似文献
158.
The present study examines how language use (e.g., personalized vs. depersonalized language) and modality (e.g., tweets vs. Facebook status updates) influence source credibility interdependently. A total of 257 participants read personalized or depersonalized health messages embedded in mock-up tweets or Facebook status updates. The results show that users perceive depersonalized tweets as more credible than depersonalized status updates posted on Facebook. On the other hand, personalized status updates on Facebook generate higher credibility judgments than personalized tweets. The findings are discussed in light of the MAIN model as well as the preconceived user expectations and communication norms of social media. 相似文献
159.
Jordan J. Smith Philip J. Morgan Ronald C. Plotnikoff David F. Stodden David R. Lubans 《Journal of sports sciences》2016,34(8):772-779
The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered “at-risk” of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys. 相似文献
160.
Daniel D. Bingham Silvia Costa Stacy A. Clemes Ash C. Routen Helen J. Moore Sally E. Barber 《Journal of sports sciences》2016,34(20):2005-2010
This study presents a worked example of a stepped process to reliably estimate the habitual physical activity and sedentary time of a sample of young children. A total of 299 children (2.9 ± 0.6 years) were recruited. Outcome variables were daily minutes of total physical activity, sedentary time, moderate to vigorous physical activity and proportional values of each variable. In total, 282 (94%) provided 3 h of accelerometer data on ≥1 day and were included in a 6-step process: Step-1: determine minimum wear-time; Step-2: process 7-day-data; Step-3: determine the inclusion of a weekend day; Step-4: examine day-to-day variability; Step-5: calculate single day intraclass correlation (ICC) (2,1); Step-6: calculate number of days required to reach reliability. Following the process the results were, Step-1: 6 h was estimated as minimum wear-time of a standard day. Step-2: 98 (32%) children had ≥6 h wear on 7 days. Step-3: no differences were found between weekdays and weekend days (P ≥ 0.05). Step-4: no differences were found between day-to-day variability (P ≥ 0.05). Step-5: single day ICC’s (2,1) ranged from 0.48 (total physical activity and sedentary time) to 0.53 (proportion of moderate to vigorous physical activity). Step-6: to reach reliability (ICC = 0.7), 3 days were required for all outcomes. In conclusion following a 7 day wear protocol, ≥6 h on any 3 days was found to have acceptable reliability. The stepped-process offers researchers a method to derive sample-specific wear-time criterion. 相似文献