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ABSTRACT

The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = ?0.26 to 0.18) and CMJ and DJ (Kappa = ?0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists.  相似文献   
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This article examines how two important Brazilian newspapers (Floha de S. Paulo and O Globo) covered the UN Conference on Environment and Development (UNCED) or Earth Summit. The analysis will also determine the characteristics of the environmental media and its significance when it comes to coverage of environmental issues. This article provides historical background information on the environmental media in the US and in Brazil, contextual information on the Earth Summit, a content analysis of stories about UNCED published by the two Brazilian newspapers. Overall, 649 news items were used to determine the type of sources used, as well as the kind of issues covered. The analysis showed that government officials were the most frequently cited sources, while environmentalists and scientists were all but ignored as news sources. The analysis also indicated that economic issues were surprisingly prominent in the coverage. These results are compatible with the previous studies done in several countries and indicate that environmental media are still extremely reliant on "official" voices. The finding also highlight the fact that the range of issues covered by the environmental media largely reflects the perceived public agenda.  相似文献   
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Zusammenfassung In der Produktfamilienentwicklung werden durch zwei Entwicklungsprozesse, Domain und Application Engineering, zun"achst wiederverwendbare Entwicklungsartefakte produziert, um diese anschlie?end zur Konstruktion von kundenspezifischen Applikationen einzusetzen. Die Wiederverwendbarkeit wird durch die explizite Definition der Variabilit"at der geplanten Applikationen einer Produktfamilie erzielt. Diese proaktive Wiederverwendung ist bisher in den konstruktiven Entwicklungsphasen realisiert, jedoch noch nicht im Test. Mit ScenTED (Scen_ario based TE_st Case D_erivation) wird in diesem Beitrag eine wiederverwendungsorientierte Technik zur Testfallerstellung f"ur den Systemtest, dem Test eines ausf"uhrbaren Systems gegen spezifizierte Use-Cases, von Produktfamilien vorgestellt. ScenTED basiert auf zwei Kernideen: der Erhaltung der Variabilit"at in Testf"allen und der Szenario-basierten Verfeinerung der Testf"alle. Durch die Erhaltung der Variabilit"at wird die Wiederverwendbarkeit von Testf"allen gesichert; die Szenario-basierte Verfeinerung erm"oglicht Nachvollziehbarkeit durch die durchg"angige Nutzung von Szenarien. In diesem Beitrag wird die ScenTED-Technik an einem Beispiel erl"autert und Erfahrungen aus dem industriellen Einsatz diskutiert.
Product family engineering consists of two development processes: Domain engineering and application engineering. Reuseable artefacts are created in the domain engineering process. These artefacts are used for the creation of customer specific applications during the application engineering process. Reusability is achieved with the explicit definition of variability that specifies the potential applications of the product family. The proactive reuse has been realized in the construnction phases of the development process, but not within the test phases. We propose ScenTED (Scen_ario based TE_st Case D_erivation) for the creation of reusable test cases for a use case based system testing in product family engineering. ScenTED has two key ideas: The first is the preservation of variability in test cases and the second idea is the scenario-based refinement of test cases. The preservation of variability ensures the reusability of test cases. The scenario-based refinement enables the traceability from requirements to test cases. We present the ScenTED technique in this article with an example and discuss an industrial case study.
CR Subject Classification D2.5  相似文献   
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ABSTRACT

This study aimed to examine the effects of two jump squat (JS) training programs involving different loading ranges in under-20 soccer players during a preseason period. Twenty-three elite young soccer players performed sprint speed (at 5-, 10-, and 20-m), change-of-direction (COD) speed, JS peak-power (PP), and countermovement jump (CMJ) tests pre and post four weeks of training. Athletes were pair-matched in two groups according to their optimum power loads (OPL) as follows: lower than OPL (LOPL; athletes who trained at a load 20% lower than the OPL) and higher than OPL (HOPL; athletes who trained at a load 20% higher than the OPL). Magnitude-based inferences were used to compare pre- and post-training measures. Meaningful increases in the PP JS were observed for both groups. Likely and possible improvements were observed in the 5- and 10-m sprint velocity in the LOPL group. Meanwhile, possible and likely improvements were observed in the CMJ, 5- and 10-m sprint velocity, and COD speed in the HOPL group. Overall, both training schemes induced positive changes in athletic performance. Soccer coaches and sport scientists can implement the JS OPL-based training schemes presented here, either separately or combined, to improve the physical performance of youth soccer players.  相似文献   
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β-hydroxy-β-methylbutyrate (calcium: HMB-Ca and free acid: HMB-FA) and α-hydroxyisocaproic acid (α-HICA) are leucine metabolites that have been proposed to improve body composition and strength when combined with resistance exercise training (RET). In this double-blind randomized controlled pragmatic trial, we evaluated the effects of off-the-shelf supplements: α-HICA, HMB-FA and HMB-Ca, on RET-induced changes in body composition and performance. Forty men were blocked randomized to receive α-HICA (n?=?10, fat-free mass [FFM]?=?62.0?±?7.1?kg), HMB-FA (n?=?11, FFM?=?62.7?±?10.5?kg), HMB-Ca (n?=?9, FFM?=?65.6?±?10.1?kg) or placebo (PLA; n?=?10, FFM?=?64.2?±?5.7?kg). The training protocol consisted of a whole-body resistance training routine, thrice weekly for 8 weeks. Body composition was assessed by dual-energy x-ray absorptiometry (DXA) and total body water (TBW) by whole-body bioimpedance spectroscopy (BIS), both at baseline and at the end of weeks 4 and 8. Time-dependent changes were observed for increase in trunk FFM (p?相似文献   
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The GlobalEd Project employs a technology richenvironment for high school students who wishto participate in a simulation of internationalrelations and negotiation. A simulationconsists of negotiations on a variety ofinternational policy issues conducted bystudents from 10–15 schools through anInternet-based interface. This study reportsthe findings of 234 high school participants'changes in academic and technologyself-efficacy skills, as well as knowledge,attitudes and behaviors related to academicpreparation and performance, the use ofeducational technology, and associated outcomesfrom participating in a simulation ofinternational relations. The results arediscussed in terms of the current literature onself-efficacy and gender differences incognitive process.  相似文献   
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While universal school‐based social and emotional learning (SEL) programs claim to target various SEL competencies, earlier reviews have not provided a clear overview of the competencies in question. We therefore wished to identify the competencies targeted in SEL programs for secondary school students. We also aimed to examine the effects of these programs on SEL competencies and psychosocial health. The specific SEL competencies directly addressed in the programs' primary learning targets were identified based on the Collaborative for Academic, Social and Emotional Learning (CASEL) framework for SEL. Five bibliographic databases (PubMed, PsychINFO, Education Resources Information Center (ERIC), Applied Science Premier (ASP), and Web of Science) were searched for relevant research papers published between 2014 and 2018. We included 40 studies that investigated 32 programs focusing on two or more SEL competencies. While most programs targeted four or five of the SEL competencies, many of the included studies did not measure the programs' effects on all the competencies targeted. Our results showed that the SEL programs had substantial effects on the SEL competencies they addressed and on psychosocial health. Although the programs focused predominantly on self‐management skills and relationship skills, the largest summary effects were found for self‐awareness and social awareness.  相似文献   
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