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1.
We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the ep index that equals the Ptop 1%/Ptop 10% ratio. By using the ep index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The ep index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk.  相似文献   
2.
Background: Motor skill (MS) competence is an important contributing factor for healthy development.

Purpose: The goal was to test the effectiveness of primary school physical education (PE) on MS and physical fitness (PF) development.

Methods: Three classes (n?=?60, aged 9.0?±?0.9) were randomly assigned to three diverse conditions during a school year: two PE lessons/week (PE-2), three PE lessons/week (PE-3), and no PE lessons control group (CG). BMI, skinfolds, PF (9-min run/walk, sit-up, modified pull-ups), gymnastics, soccer, handball, basketball and track-and-field skills were evaluated. Effect sizes (d) were reported as magnitude of change.

Results: Skinfolds significantly increased only in CG (d?=?1.21). PF composite z-scores improved in PE-3 (d?=?0.61), but decreased in PE-2 (d?=?0.57), and had no changes in CG. Statistically significant improvement was verified in gymnastics and handball skills in both experimental groups (gymnastic: d?=?2.95 and d?=?2.61 for PE-3 and PE-2, respectively; handball: d?=?1.87 and d?=?0.57 for PE-3 and PE-2, respectively), and no changes were seen in CG. In soccer, there were improvements only in the PE-3 (d?=?0.55), and in basketball only in PE-2 (d?=?0.46). There were no changes in any group for track-and-field skills.

Conclusions: PE programs can effectively promote PF and MS development.  相似文献   
3.
ABSTRACT

We performed a randomized, controlled trial to analyse the effects of resistance training (RT) on cognitive and physical function among older adults. Fifty participants (mean age 67 years, ~60% woman) were randomly assigned to an RT program or a control group. Participants allocated to RT performed three sets of 10-15RM in nine exercises, three times per week, for 12-weeks. Control group did not perform any exercise. Variables included cognitive (global and executive function) and physical function (gait, mobility and strength) outcomes. At completion of the intervention, RT was shown to have significantly mitigated the drop in selective attention and conflict resolution performance (Stroop test: -494.6; 95%CI: -883.1; ?106.1) and promoted a significant improvement in working memory (digit span forward: -0.6; 95%CI: ?1.0; ?0.1 and forward minus backward: -0.9; 95% CI: ?1.6; ?0.2) and verbal fluency (animal naming: +1.4, 95%CI 0.3, 2.5). No significant between-group differences were observed for other cognitive outcomes. Regarding physical function, at completion of the intervention, the RT group demonstrated improved fast-pace gait performance (?0.3; 95% CI: ?0.6; ?0.0) and 1-RM (+21.4 kg; 95%CI: 16.6; 26.2). No significant between-group differences were observed for other mobility-related outcomes. In conclusion, RT improves cognitive and physical function of older adults.  相似文献   
4.
Given that physical activity (PA) tends to decrease with age during adolescence, addressing factors that affect change is important. This study examined the similarity and interdependence of PA as influenced by psychosocial factors among adolescent best friend dyads. A total of 660 adolescents, representing 330 best friend dyads, completed questionnaires with regard to PA, sitting time, perceived exercise benefits and barriers, physical self-perception and social support for PA. Dyads were also identified as reciprocal and non-reciprocal best friends; reciprocal means that both considered each other best friends and non-reciprocal were those in which only one considered the other a best friend. Data were analysed using a hierarchical linear model framework. Results indicated significant similarities between reciprocal best friend dyads for PA and sitting time, and for sitting time in non-reciprocal best friends (P values <.01). Psychosocial variables were associated with PA in reciprocal best friend dyads and with sitting time in reciprocal and non-reciprocal best friend dyads. Best friend gender, regular sports practice of the person, perceived exercise barriers of the best friend and best friend social support were the best predictors for PA.  相似文献   
5.
The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13–17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6–10 repetitions at 60–70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50–80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (< 0.01) and increase in fat-free mass (< 0.01), VO2peak (< 0.01), 1 RM for leg press (< 0.01) and bench press (< 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (< 0.05) and leptin (< 0.05), as well as in insulin resistance (< 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls.  相似文献   
6.
Peer and near-peer teaching programs are common in medical undergraduate courses. However, there are no studies that have investigated the effectiveness of a near-peer teaching program on the academic performance of undergraduate students pursuing sport and exercise science coursework. This study was conducted to analyze the effectiveness of such a program for students who participated in a course on the functional anatomy of the locomotor apparatus. A total of 39 student participants were divided into two groups: students in one group voluntarily attended at least one session of a near-peer teaching program, and students in the other group attended no sessions. The final grade (range 0–100%) was recorded and used as an indicator of academic performance. The final grade of students who attended the near-peer teaching program (69.5 ± 16.0%) was 38.7% higher (P = 0.002, d = 1.06) than those who did not (50.1 ± 20.4%). When the academic performance of the same students was evaluated in another course (exercise physiology) that did not offer a near-peer teaching program, there were no significant differences between the groups (students who attended or did not attend the near-peer teaching program). A significant positive association was found between near-peer teaching program frequency and the number of students approved and not approved in the course (P = 0.041). A significant difference (P = 0.001) was found in the attendance at regular classes between the group who participated in the near-peer teaching program (median: 62 hours; IQR [interquartile ranges]: 4.0 hours) and those who did not (median: 58 hours; IQR: 4.0 hours). Gender was not a moderating factor on academic performance or near-peer teaching program attendance. These results highlight the effectiveness of a near-peer teaching program on the academic performance of students from a sport and exercise science degree program while enrolled in an anatomy course. Anat Sci Educ. © 2018 American Association of Anatomists.  相似文献   
7.
Currently, medical education context poses different challenges to anatomy, contributing to the introduction of new pedagogical approaches, such as computer-assisted learning (CAL). This approach provides insight into students' learning profiles and skills that enhance anatomy knowledge acquisition. To understand the influence of anatomy CAL on spatial abilities, a study was conducted. A total of 671 medical students attending Musculoskeletal (MA) and Cardiovascular Anatomy (CA) courses, were allocated to one of three groups (MA Group, CA Group, MA + CA Group). Students' pre-training and post-training spatial abilities were assessed through Mental Rotations Test (MRT), with scores ranging between 0-24. After CAL training sessions, students' spatial abilities performance improved (9.72 ± 4.79 vs. 17.05 ± 4.57, P < 0.001). Although male students in both MA Group and CA Group show better baseline spatial abilities, no sex differences were found after CAL training. The improvement in spatial abilities score between sessions (Delta MRT) was correlated with Musculoskeletal Anatomy training sessions in MA Group (r = 0.333, P < 0.001) and MA + CA Group (r = 0.342, P < 0.001), and with Cardiovascular Anatomy training sessions in CA Group (r = 0.461, P = 0.001) and MA + CA Group (r = 0.324, P = 0.001). Multiple linear regression models were used, considering the Delta MRT as dependent variable. An association of Delta MRT to the amount of CAL training and the baseline spatial abilities was observed. The results suggest that CAL training in anatomy has positive dose-dependent effect on spatial abilities.  相似文献   
8.
A pipelined architecture for distributed text query evaluation   总被引:1,自引:0,他引:1  
Two principal query-evaluation methodologies have been described for cluster-based implementation of distributed information retrieval systems: document partitioning and term partitioning. In a document-partitioned system, each of the processors hosts a subset of the documents in the collection, and executes every query against its local sub-collection. In a term-partitioned system, each of the processors hosts a subset of the inverted lists that make up the index of the collection, and serves them to a central machine as they are required for query evaluation. In this paper we introduce a pipelined query-evaluation methodology, based on a term-partitioned index, in which partially evaluated queries are passed amongst the set of processors that host the query terms. This arrangement retains the disk read benefits of term partitioning, but more effectively shares the computational load. We compare the three methodologies experimentally, and show that term distribution is inefficient and scales poorly. The new pipelined approach offers efficient memory utilization and efficient use of disk accesses, but suffers from problems with load balancing between nodes. Until these problems are resolved, document partitioning remains the preferred method. Alistair Moffat was supported by the Australian Research Council, the ARC Special Research Center for Perceptive and Intelligent Machines in Complex Environments, and the NICTA Victoria Laboratory. William Webber and Justin Zobel were supported by the Australian Research Council. Ricardo Baeza-Yates was supported by Grant P01-029-F from Millennium Initiative of Mideplan, Chile; and by the University of Melbourne as a visiting scholar at the time this project was undertaken.  相似文献   
9.
The paper considers how attributes and skills fundamental to the information profession may be applied to the development and management of Web-based services and resources. It also looks at the need for the acquisition of new skills as part of a continuing professional development programme. The report considers the changing role of the Webmaster and the implications this might have in terms of the role of information professionals. To offer a practical example, from within the healthcare sector, the article goes on to describe the development of BMA Library Online. This is the BMA Library's own suite of Web-based information services and resources for personal members, institutional members and staff. The library's own Web team has been responsible for the development and maintenance of BMA Library Online. To conclude, the paper looks forward to future possibilities for information professionals as Web developers and at how this might be influenced by changes in the Webmaster role. It is crucial that skills and expertise are shared as the roles that go to make up a Webmaster or Webmaster team continue to merge and evolve, and with the possible wider distribution of provision of Web content within organizations.  相似文献   
10.
The aim of this study was to determine the influence of breathing frequency and tidal volume on resting heart rate variability in children aged 9 years (n = 29) and 16 years (n = 19). Heart rate variability was measured in four conditions: (1) without the control of ventilation followed at random by (2) a fixed breathing frequency of 12 breaths x min(-1), (3) a breathing frequency of 12 breaths x min(-1) but with a fixed tidal volume of 30% vital capacity and (4) a fixed breathing frequency of 6 breaths x min(-1) and a tidal volume of 30% vital capacity. A total of 128 RR intervals (the time between two spikes in the heart rate) were detected and absolute high- and low-frequency spectral components were calculated using autoregressive modelling. The younger children were unable to control ventilation to achieve conditions 3 and 4; therefore, a 2 x 2 (group x condition) analysis of variance was used to analyse conditions 1 and 2. There were significant interactions between group and heart rate variability conditions for the low-frequency component and the ratio of low to high frequencies (P < 0.001). The main effect for condition showed that at 12 breaths x min(-1) with no fixed tidal volume there was a significantly higher standard deviation of the RR interval, total power and high-frequency (P< 0.01) and low-frequency spectral components (P < 0.05) than in the condition with no ventilatory control. Across the four breathing conditions for the older participants, the high-frequency spectral component was significantly higher in the condition at 6 breaths x min(-1) with a fixed tidal volume than in that with no ventilatory control (P < 0.005); the ratio of high to low frequencies was significantly lower for the spontaneous condition than those performed at 12 breaths x min(-1) (P < 0.001). The results provide evidence of the need for ventilatory control when assessing short-term resting heart rate variability in children.  相似文献   
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