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We tested a simple and compact device designed for manual resistance training in conditions of microgravity (Self-Powered Rope Trainer Duo (SPoRT Duo)) to increase muscle performance. Twenty-four participants (20.8 ± 2.1 years) were randomly assigned to a manual resistance group (n = 12) and a free-weight group (n = 12). Participants performed eight exercises (three sets; 8–12 efforts) either with free weights or the SPoRT Duo twice a week for 6 weeks. Maximal isometric force of trunk flexion, back extension and chest press increased (P at least 0.01, d at least 0.52) both in the manual resistance group (18.4% ± 15.0%; 32.7% ± 22.7%; 15.3% ± 9.7%) and free-weight group (18.0% ± 13.9%; 26.6% ± 28.9%; 13.3% ± 7.6%). The change in maximal isometric force of wide grip row in both groups (d at best 0.38) did not reach statistical significance (P at best 0.08). The squat one-repetition-maximum increased in the manual resistance group (29.8% ± 22.1%) and the free-weight group (32.4% ± 26.6%). Jump height, determined by a jump-and-reach test, increased in the free-weight group (9.8% ± 13.2%) but not in the manual resistance group (2.0% ± 8.5%). Manual resistance training was equally effective in increasing strength as traditional resistance training with free weights. This apparatus is a useful addition to current in-flight exercise systems.  相似文献   
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The article presents a survey on usage statistics management in academic libraries in France. The objective is to provide empirical evidence on real methods and processes, best practices and problems experienced by librarians. The survey adapted Baker and Read's methodology to the French context. One‐third of French academic libraries answered the survey. Results show that usage statistics are crucial for librarians' daily work. COUNTER reports are mostly used, specifically the JR1 format. Two‐thirds of the libraries enhance the usage statistics with other data. Librarians face three major difficulties: lack of time, lack of usage data produced by French vendors, and the need for customized tools. The article contains a short literature review and ends with recommendations for further studies. It is the first published survey on usage data management in France and allows for comparison with results from other countries.  相似文献   
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The Science Foundation Programme (SFP) was launched in 1991 at the University of Natal, Pietermaritzburg, South Africa in an attempt to equip a selected number of matriculants from historically disadvantaged schools with the skills, resources and self-confidence needed to embark on their tertiary studies. Previous research within the SFP biology component suggests that a major contributor to poor achievement and low retention rates among English second language (ESL) students in the Life Sciences is the inadequate background knowledge in natural history. In this study, SFP student background knowledge was assessed along a continuum of language dependency using a set of three probes. Improved student performance in each of the respective assessments examined the extent to which a sound natural history background facilitated meaningful learning relative to ESL proficiency. Student profiles and attitudes to biology were also examined. Results indicated that students did not perceive language to be a problem in biology. However, analysis of the student performance in the assessment probes indicated that, although the marine course provided the students with the background knowledge that they were initially lacking, they continued to perform better in the drawing and MCQ tools in the post-tests, suggesting that it is their inability to express themselves in the written form that hampers their development. These results have implications for curriculum development within the constructivist framework of the SFP.  相似文献   
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The issue whether creationist accounts of the origins of life should be taught in science education alongside or even instead Darwin’s theory of evolution is controversial in many countries. In 2002 there was a controversy around teaching creationism in science classes at a secondary school in England. The research presented in this paper uses this controversy around teaching creationism/evolution as case study to find out more about the public representation of science education. Here it focuses on the question who the experts were that appeared in the press coverage and examines the role of scientific experts in this controversy. Expertise is a key resource in many public controversies involving science and can also have an impact on decision-making processes and on the public opinion. Also the way expert sources are presented in media accounts of socio-scientific controversies can have an effect on how their credibility is perceived and the arguments being made.  相似文献   
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R&D outsourcing is often conducted during the early, market-distant stages of the innovation process. However, the main obstacle to this potentially efficient interfirm specialization is the high danger of moral hazard. Most organizational mechanisms fail to control that type of opportunism because of information asymmetries, even ex post. In the theory of incomplete contracts, this problem is mitigated by assigning the control rights to the supplier. To date, empirical studies have mainly investigated the interfirm distribution of the control rights. However, we do not know yet which concrete control right is crucial with regard to supplier opportunism, which is the decisive dependent variable. Our study addresses this research gap. For the first time, we extend the empirical focus from biotechnology and pharmaceutical firm alliances to a cross-industry sample of 113 collaboration cases. The results show the effectiveness of contracts that ex ante assign patent ownership rights to the supplier. The findings are also relevant for management practice because the majority of practitioners do not use this contract type yet, although there is no sign of an effective alternative.  相似文献   
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