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Abstract

A large body of evidence now shows that higher protein intakes (2–3 times the protein Recommended Dietary Allowance (RDA) of 0.8 g/kg/d) during periods of energy restriction can enhance fat-free mass (FFM) preservation, particularly when combined with exercise. The mechanisms underpinning the FFM-sparing effect of higher protein diets remain to be fully elucidated but may relate to the maintenance of the anabolic sensitivity of skeletal muscle to protein ingestion. From a practical point of view, athletes aiming to reduce fat mass and preserve FFM should be advised to consume protein intakes in the range of ~1.8–2.7 g kg?1 d?1 (or ~2.3–3.1 g kg?1 FFM) in combination with a moderate energy deficit (?500 kcal) and the performance of some form of resistance exercise. The target level of protein intake within this recommended range requires consideration of a number of case-specific factors including the athlete's body composition, habitual protein intake and broader nutrition goals. Athletes should focus on consuming high-quality protein sources, aiming to consume protein feedings evenly spaced throughout the day. Post-exercise consumption of 0.25–0.3 g protein meal?1 from protein sources with high leucine content and rapid digestion kinetics (i.e. whey protein) is recommended to optimise exercise-induced muscle protein synthesis. When protein is consumed as part of a mixed macronutrient meal and/or before bed slightly higher protein doses may be optimal.  相似文献   
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This paper explores the prospective transition of immigrant and native students in France from lower to upper secondary school. Because they are more likely to be tracked to less prestigious (vocational) tracks, immigrant and immigrant‐origin students are significantly disadvantaged at this key academic stage in comparison with the children of native families. Primary and secondary sources of educational disadvantage are explored to explain this phenomenon. Primary effects appear to account for the entire initial disadvantage, while secondary effects could have a positive impact for immigrant‐origin students. Nonetheless, immigrant families appear to be more conservative than native families and may need stronger evidence that their children will succeed in upper secondary school.  相似文献   
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In this article, we explore how youth audiences evaluate the quality of youth-produced films. Our interest stems from a dearth of ways to measure the quality of what youth produce in artistic production processes. As a result, making art in formal learning settings devolves into either romanticized creativity or instrumental work to improve skills in core content areas. We conducted focus groups with 38 youth participants where they viewed four different films produced by the same youth media arts organization that works with young people to produce short-form, autobiographical documentaries. We found that youth focused their evaluations on identifying the films' genre and content and on assessing how well the filmmakers' creative decisions fit with identifications of genre and content. Evaluations were mediated by audiences' expectations and seemed to inform judgments of quality and creativity. We hope that our work can inform the design of formal learning spaces where young people are producing narrative art.  相似文献   
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The minimal realization theory for input–output maps that arise from finite- dimensional, continuous time, bilinear systems is discussed. It is shown that an observed bilinear system (i.e. a bilinear system together with an observation functional, but without a fixed initial state) is completely determined by its input–output correspondence, i.e. its multivalued input–output map. A precise formulation and proof of the result are given that continuous canonical forms for bilinear systems do not exist. This is done by adapting to the bilinear case an idea due to Hazewinkel and Kalman for the case of linear systems. In addition, the proof presented here has the advantage of not involving any algebraic geometry, which makes it considerably simpler than the original proof of the linear systems result.  相似文献   
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Engineering education is facing new challenges to effectively provide the appropriate skills to future engineering professionals according to market demands. This study proposes a model based on active learning methods, which is expected to facilitate the acquisition of the professional skills most highly valued in the information and communications technology (ICT) market. The theoretical foundations of the study are based on the specific literature on active learning methodologies. The Delphi method is used to establish the fit between learning methods and generic skills required by the ICT sector. An innovative proposition is therefore presented that groups the required skills in relation to the teaching method that best develops them. The qualitative research suggests that a combination of project-based learning and the learning contract is sufficient to ensure a satisfactory skills level for this profile of engineers.  相似文献   
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Abstract

Variable practice has been shown to be an effective strategy to improve open motor skills. However, the usefulness of this procedure in closed motor skills remains controversial. The following study has the objective of analysing the effects of variability practice in the improvement of a closed skill. The skill studied has been the tennis serve. Thirty young tennis players (13 ± 1.52 years), divided in two groups, took part in this study. One group practiced in variable conditions and the other group in consistency conditions. Both groups performed 12 training sessions (60 serves/session). The variable practice group improved their accuracy significantly compared with the consistency group (F3.25 = 3.078; P = 0.035). The velocity of serve increased after training in both groups (F3.25 = 15.890; P = 0.001). The practice in variable conditions seems to be effective in improving the performance of the tennis serve.  相似文献   
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The purpose of this contribution is to move the study of performing rights forward and away from discussion of matters of principle to matters of implementation. Our procedure is to identify the chronological steps which have to be taken by composers or their representatives in ensuring that their property right can be exploited, resulting in payment for performances. At each step we shall attempt to offer observations, based principally but by no means solely on UK experience, on both the economic and legal issues that arise. The first stage in the exploitation of copyright is to create a work in a discernible form. In music this has traditionally taken the form of a score. However, today most popular music will take the form of a taped performance. This is followed by critical discussion of the term of copyright protection and whether a monopoly is created in respect of performing rights. In addition to performing rights, account has also to be taken of performers' rights, raising issues of where copyright protection ends and performers' rights begin. The second stage of exploitation is publication, promotion and performance of the work, a matter so complex that it has necessitated the establishment of collective organisations of authors and publishers to be effective. Policy issues arise about the relations between the members of such organisationsinter se, and between the organisations and users, and these are illustrated by a number of examples from the history of the British Performing Right Society. Disputes led to the establishment of specialist tribunals in the UK and elsewhere, and there have also been investigations of collecting societies by the British and EC competition authorities. The global market for music means that such issues transcend national frontiers, and there is some discussion of how performing rights are enforced internationally. The paper concludes by identifying a number of major issues: whether or not collecting societies operate against the consumer interest (it is suggested, generally not); the extent to which serious music is or should be subsidised by diversion of the income of the collecting societies in its support; and the possible extension of collective copyright administration into other fields, against the background of ever-increasing cross-border activity in cultural matters generally.  相似文献   
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