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排序方式: 共有327条查询结果,搜索用时 15 毫秒
41.
Paolo Castelnovo Massimo Florio Stefano Forte Lucio Rossi Emanuela Sirtori 《Research Policy》2018,47(9):1853-1867
The Large Hadron Collider at CERN, the European Organisation for Nuclear Research, is the world’s highest-energy particle accelerator. Its construction (1995–2008) required frontier technologies and close collaboration between CERN scientists and contracting firms. The literature on “Big Science” projects suggests that this collaboration generated economic spillovers, particularly through technological learning. CERN granted us access to its procurement database, including suppliers of LHC from 35 countries for orders over 10,000 Swiss Francs. We gathered balance-sheet data for more than 350 of these companies from 1991 to 2014, which include the years before and after that of the first order received. The study assesses, in quantitative terms, whether becoming a CERN supplier induced greater R&D effort and innovative capacity, thus enhancing productivity and profitability. The findings – which controlled for firms’ observable characteristics, macroeconomic conditions, and unobserved time, country, industry and firm-level fixed effects – indicate a statistically significant correlation between procurement events and company R&D, knowledge creation and economic performance. The correlation is chiefly driven by high-tech orders; for companies receiving non-high-tech orders, it is weaker, or even statistically not significant. 相似文献
42.
Paolo M. Cunha Alex S. Ribeiro Crisieli M. Tomeleri Brad J. Schoenfeld Analiza M. Silva Mariana F. Souza 《Journal of sports sciences》2018,36(14):1564-1571
The aim of this study was to analyze the effects of resistance training (RT) performed with 1 or 3 sets per exercise on osteosarcopenic obesity (OSO) syndrome parameters in older women. Sixty-two older women (68.0 ± 4.3 years, 26.8 ± 4.4 kg/m2) participated in a 12-week RT program. Participants were randomly assigned into one of the three groups: two training groups that performed either 1 set (G1S, n = 21) or 3 sets (G3S, n = 20) 3 times weekly, or a control group (CG, n = 21). Body composition was assessed by dual X-ray absorptiometry, strength was evaluated by 1 repetition maximum testing. The G3S presented significantly higher strength changes than G1S. The changes for percentage of body fat were higher for G3S compared to G1S. There was no difference in skeletal muscle mass between G3S and G1S, however both training groups displayed greater increases in this outcome compared to CG. There was no effect for bone mineral density. The overall analysis indicated higher (P < 0.05) positive changes for G3S than G1S (composed Z-score: G3S = 0.62 ± 0.40; G1S = 0.11 ± 0.48). The results suggest that a 12-week RT period is effective to improve the risk factors of OSO, and that 3 sets induce higher improvements than a single set. 相似文献
43.
Leonardo S. Fortes José R. A. Nascimento-Júnior Arnaldo L. Mortatti Dalton Roberto Alvas Araújo de Lima-Júnior Maria E. C. Ferreira 《Research quarterly for exercise and sport》2018,89(3):332-339
It seems that dehydration may impair decision-making performance in athletes. Purpose: This study aimed to investigate the influence of dehydration on passing decision-making performance in soccer players. Method: Participants were 40 male soccer players (Mage = 22.3 ± 2.3 years) who agreed to participate in the study and were randomly assigned to the following conditions: control (CON), dehydration (DEH), and euhydration (EUH). The players played in 2 games of 90 min in duration (2 45-min halves) followed by 2 15-min halves (overtime) with and without proper hydration. The Game Performance Assessment Instrument (GPAI) was considered for the analysis of passing decision making. Results: The GPAI analysis indicated effective reduction in the decision-making index in the DEH condition compared with the EUH and CON conditions, F(2, 38) = 31.4, p < .05, ES = 0.8. Conclusions: In conclusion, dehydration may be considered a mediating factor in the passing decision-making performance of male soccer athletes. 相似文献
44.
This paper provides an overview of the knowledge management systems (KMSs) adopted by small and medium enterprises (SMEs). KMSs are divided into two categories: knowledge management tools (KM-Tools) and knowledge management practices (KM-Practices). On the basis of the analysis of the literature, two research questions (RQs) were identified and addressed through semi-structured interviews carried out in a sample of 35 SMEs operating in high-tech industries. The first RQ concerns the degree of adoption of KMSs by SMEs. The second RQ regards the relationship between KM-Tools and KM-Practices. As far as the degree of adoption of KMSs, the paper highlights that SMEs are not a homogeneous world but there are a variety of approaches and behaviours. As far as the relationship between the degree of adoption of KM-Tools and KM-Practices, the paper identifies three groups of SMEs that seem to point out the stages of the process of adoption of KMSs: Introduction, SMEs that deal with the process of knowledge management exploiting practices and tools that are already known; Growth, SMEs that adopt specialist practices of knowledge management acquiring new organisational and managerial competence in the field of knowledge management; Maturity, SMEs that invest in new technology and that acquire new technological competence in the field of knowledge management. This categorisation paves the way for further theoretical and practical implications for both managers and policy makers. 相似文献
45.
Paolo M. Cunha Crisieli M. Tomeleri Matheus A. do Nascimento João Pedro Nunes Melissa Antunes Hellen C. G. Nabuco 《Journal of sports sciences》2013,31(24):2843-2848
ABSTRACTThe main purpose of this study was to compare the effects of resistance training (RT) performed with different training volumes on phase angle (PhA), body water components, and muscle quality (MQ) in untrained older adult women. A second purpose was to assess the relationship between PhA and MQ. Sixty-two older adult women (68.6 ± 5.0 years, 65.2 ± 13.3 kg, 156.1 ± 6.2 cm) were randomly assigned into one of the three groups: two training groups performed either 1 set (G1S) or 3 sets (G3S), or a control group (CG). Body water components and PhA were estimated by bioelectrical impedance (BIA). MQ was determined by dividing skeletal muscle mass estimated by dual-energy absorptiometry (DXA) by total muscle strength from three exercises. After the intervention period, both training groups demonstrated improvements (P < 0.05) when compared with CON for intracellular water, total body water, PhA, and MQ. These results suggest that RT can improve PhA, body water components, and MQ after 12 weeks of RT in untrained older women, regardless of training volume. Furthermore, changes in MQ were positively correlated with changes in PhA (r = 0.60, P < 0.01). 相似文献
46.
Fabio Lucidi Arnaldo Zelli Luca Mallia Caterina Grano Paolo M. Russo Cristiano Violani 《Journal of sports sciences》2013,31(5):447-456
Abstract In this study, we assessed the longitudinal effects of social-cognitive mechanisms on the self-reported use of doping substances and supplements among Italian high school students. In total, 1232 students completed questionnaires measuring various psychological factors hypothesized to influence students' intention to use substances. Three months later, 762 of the students completed the same questionnaires a second time and also reported their use of substances during the time between assessments. Overall, the percentages of students using doping substances (2.1%) or supplements (14.4%) were consistent with values reported in the literature. Analysis of the data showed that adolescents' intention to use doping substances increased with stronger attitudes about doping, stronger beliefs that significant others would approve of their use, a stronger conviction that doping use can be justified, and a lowered capacity to resist situational pressure or personal desires. In turn, stronger intentions and moral disengagement contributed to a greater use of doping substances during the previous 3 months. Doping use was also correlated significantly to supplementation. In conclusion, our results provide novel information about some of the psychological processes possibly regulating adolescents' use of doping substances and supplements. The results also highlight possible areas for future study and intervention, focusing on the prevention of adolescents' substance use. 相似文献
47.
Paulo S. Roberto Amorim Andrew Hills Nuala Byrne 《Research quarterly for exercise and sport》2013,84(2):380-385
Abstract Eighty-two male college students were divided into three equal-size groups for the purpose of testing the transfer effects between motor skills judged similar in perceptual components but different in motor components. Criterion measures of gross movement ability and static balance were analyzed and practice tasks similar to these criterion measures in perceptual components but different in motor components were developed. All subjects were pretested on the criterion measures, after which groups 1 and 2 practiced 3 min. per day for 28 days on the practice tasks while group 3 performed unrelated isometric exercises. On the post-test, the experimental groups were found to be significantly superior to the control group on gross movement accuracy and static balance. It was implied that the transfer resulted from the similarity in perceptual components of the two motor skills, and that perceptual abilities were subject to improvement through practice. 相似文献
48.
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50.
Thaís Cyrino de Mello Forato Roberto de Andrade Martins Maurício Pietrocola 《Science & Education》2012,21(5):657-682
This article presents the main results of a research examining the didactic transposition of history and philosophy of science
in high school level. The adaptation of history of science to this particular level, addressing some aspects of the nature
of science aiming at the students’ critical engagement, was analyzed by examining both the historiographic requirements of
history of science and the pedagogical recommendations of science teaching. The research included the elaboration of a pilot
course on the history of optics, with historical texts and educational activities, and its application in a high school. We
used three episodes of the history of optics, addressing some epistemological points, especially criticizing the naive empirical-inductive
view of science. It was possible to identify a series of obstacles in using history of science and conveying philosophical
views. Their analysis resulted in devising strategies to surmount or to circumvent them. We implemented those strategies in
the classroom and analyzed the data that was obtained. As a result, we substantiated several of our proposals and found that
some solutions require improvement. We suggest some generalizations, which can be understood as initial parameters for guiding
the use of history and philosophy of science in science teaching. We used a qualitative methodology of educational research
to plan, to collect and to analyze the data, examining the interaction between students, teacher and knowledge. 相似文献