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111.

Fast unloaded movements (i.e. striking, throwing and kicking) are typically performed in a proximo‐distal sequence, where initially high proximal segments accelerate while distal segments lag behind, after which proximal segments decelerate while distal segments accelerate. The aims of this study were to examine whether proximal segment deceleration is performed actively by antagonist muscles or is a passive consequence of distal segment movement, and whether distal segment acceleration is enhanced by proximal segment deceleration. Seventeen skilled taekwon‐do practitioners were filmed using a high‐speed camera while performing a high front kick. During kicking, EMG recordings were obtained from five major lower extremity muscles. Based on the kinematic data, inverse dynamics computations were performed yielding muscle moments and motion‐dependent moments. The results indicated that thigh deceleration was caused by motion‐dependent moments arising from lower leg motion and not by active deceleration. This was supported by the EMG recordings. Lower leg acceleration was caused partly by a knee extensor muscle moment and partly by a motion‐dependent moment arising from thigh angular velocity. Thus, lower leg acceleration was not enhanced by thigh deceleration. On the contrary, thigh deceleration, although not desirable, is unavoidable because of lower leg acceleration.  相似文献   
112.
The analysis of the joint kinematics during swimming plays a fundamental role both in sports conditioning and in clinical contexts. Contrary to the traditional video analysis, wearable inertial-magnetic measurements units (IMMUs) allow to analyse both the underwater and aerial phases of the swimming stroke over the whole length of the swimming pool. Furthermore, the rapid calibration and short data processing required by IMMUs provide coaches and athletes with an immediate feedback on swimming kinematics during training. This study aimed to develop a protocol to assess the three-dimensional kinematics of the upper limbs during swimming using IMMUs. Kinematics were evaluated during simulated dry-land swimming trials performed in the laboratory by eight swimmers. A stereo-photogrammetric system was used as the gold standard. The results showed high coefficient of multiple correlation (CMC) values, with median (first–third quartile) of 0.97 (0.93–0.95) and 0.99 (0.97–0.99) for simulated front-crawl and breaststroke, respectively. Furthermore, the joint angles were estimated with an accuracy increasing from distal to proximal joints, with wrist indices showing median CMC values always higher than 0.90. The present findings represent an important step towards the practical use of technology based on IMMUs for the kinematic analysis of swimming in applied contexts.  相似文献   
113.
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   
114.
Metrics on open access (OA) availability of content published in scholarly journals (i.e. content licences, copyright ownership, and publisher‐stipulated self‐archiving permissions) are still scarce. This study implements the four core variables of the recently published Open Access Spectrum (OAS) (reader rights, reuse rights, copyright, and author posting rights) to measure the level of openness in all 1,728 Spanish scholarly journals listed in the Spanish national DULCINEA database at the end of 2015. Data exported from the database and used as variables for the analysis were: journal research area, type of publisher, type of access, self‐archiving and reuse policy, and type of Creative Commons (CC) licence used. Out of the total number of journals (1,728), 1,285 (74.5%) published their articles OA immediately after initial publication and thus received the maximum OAS score for reader rights; 37.5% of all journals used CC licences, and 79.5% allowed self‐archiving in some form. In 72% of journals, authors retained or publishers granted broad rights, which included author reuse and authorization rights (for others to reuse), whilst 13.5% did not specify any terms for copyright transfer. Similar studies could be carried out on other countries as this would enable comparisons of the general adoption and form of openness in different parts of the world.  相似文献   
115.
Early career researchers (ECRs) are of great interest because they are the new (and biggest) wave of researchers. They merit long and detailed investigation, and towards this end, this overarching paper provides a summary of the first‐year findings of a 3‐year, longitudinal study of 116 science and social science ECRs who have published nearly 1,200 papers and come from 7 countries and 81 universities. ECRs were interviewed in their own languages face‐to‐face, by Skype, or telephone. The study focused on the attitudes and behaviours of ECRs with respect to scholarly communications and the extent to which they are adopting new and disruptive technologies, such as social media, online communities, and Open Science. The main findings include: publishing in high‐impact factor journals is the only reputational game in town; online scholarly communities, and ResearchGate in particular, are gaining ground; social media are beginning to have an impact, especially in the dissemination arena; outreach activities have become more important; libraries are becoming increasingly invisible to ECRs; Open Science is not gaining traction; and more transformational ideas are being expressed, especially in the US and UK.  相似文献   
116.
Background: To minimise retrieval bias, manual literature searches are a key part of the search process of any systematic review. Considering the need to have accurate information, valid results of the manual literature search are essential to ensure scientific standards; likewise efficient approaches that minimise the amount of personnel time required to conduct a manual literature search are of great interest. Objective: The objective of this project was to determine the validity and efficiency of a new manual search method that utilises the scopus ? database. Methods: We used the traditional manual search approach as the gold standard to determine the validity and efficiency of the proposed scopus method. Outcome measures included completeness of article detection and personnel time involved. Using both methods independently, we compared the results based on accuracy of the results, validity and time spent conducting the search, efficiency. Results: Regarding accuracy, the scopus method identified the same studies as the traditional approach indicating its validity. In terms of efficiency, using scopus led to a time saving of 62.5% compared with the traditional approach (3 h versus 8 h). Conclusions: The scopus method can significantly improve the efficiency of manual searches and thus of systematic reviews.  相似文献   
117.
To explore the citation evolution of papers published in the same year but different month, we selected papers from a discipline (physical geography), a subject (diabetes: endocrine and metabolism) and a journal (Journal of Biological Chemistry) published in 2005 as research objects. These papers were divided into six groups according to the difference in publication month, and we analyzed citations to these papers for the 9 years after publication. The results showed that within 5 years after papers from physical geography were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); after that, the differences were not statistically significant. Within 5 years after papers from diabetes (endocrine and metabolism) were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Within 7 years after papers from the Journal of Biological Chemistry were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Citations of papers followed the same pattern irrespective of discipline, subject or journal: citations of papers published in the same year but different month were obviously different in the first few publishing years, but as time went on, only the difference in publication month in a calendar year did not affect the papers' longer‐term citation.  相似文献   
118.
This study seeks initial evidence for the patterns of nonverbal adaptation predictive of emotional improvement after a troubles talk conversation. A total of 128 dyads composed of two unacquainted individuals engaged in a 5-minute conversation about a stressful event, and the nonverbal behaviors of both the supportive listener and discloser were coded for immediacy. We detected a general pattern of matching between interlocutors, which was positively associated with disclosers’ reported emotional improvement above and beyond listener immediacy. Importantly, we found primary support for a discloser-matching model whereby emotional improvement is a function of disclosers matching highly immediate listeners but no support for a listener-matching model whereby emotional improvement is a function of listeners matching disclosers to signal empathy.  相似文献   
119.
The is article analyses the two main approaches for artists’ selection in the recording industry: the direct model in which large major companies directly choose new artists from the supply market, and the agency model in which small independent labels realise the first choice and, subsequently, large organisations pick their new artists among those pre-selected by independents.An empirical analysis of chart sales reveals that artists selected through the agency model exhibit a longer presence on the chart due to repeated successes, while they are slower to reach heavy success once they have entered the chart. Conversely, the direct model leads to artists with a faster path to a strong success, but the same artists have a shorter presence on the chart due to the sporadic nature of their success. The profile of artists selected through these two models is also found to be different: big international soloist stars are more frequently selected through the direct model, while national bands are more frequently selected through the agency model.The insights suggest important implications for management in the cultural industries and especially in the recording industry. Jel Codes: L82; O32  相似文献   
120.
Book reviews     
Authors and Electronic Publishing, a report produced by Alma Swan and Sheridan Brown, Key Perspectives Ltd Association of Learned and Professional Society Publishers (ALPSP) 2002. Members, £50 (US$100); Non-members £100 (US$200). ISBN 090734123-3 My Life in Science by Sydney Brenner BioMed Central Ltd, 2001; rev. edn including personal photos, 2002. Pp. 199. Paper, £14.99 recommended retail price; £10.49 for BioMed Central users ( www.biomedcentral.com/info/brenner.asp ). ISBN: 0-9540278-0-9 Understanding Copyright… in a Week by Graham P. Cornish Institute of Management, published by Hodder & Stoughton, 2000. £6.99. ISBN 0-340-78241-2 Towards Consensus on the Electronic Use of Publications in Libraries – Strategy Issues and Recommendations by Thomas Dreier Gottinger Bibliotheksschriften, 2001. Pp. 120. Paperback. Available at: http://gdz.sub.uni-goettingen.de/tecup/towacons.pdf . ISBN 3-930457-16-4. ISSN: 0943-951X  相似文献   
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