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991.
The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 +/- 122 and 668 +/- 37 W) was lower (P < 0.01) than either the highest (1074 +/- 111 and 754 +/- 56 W respectively) or the mean (1007 +/- 125 and 701 +/- 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 +/- 30 W in males and 33 +/- 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.  相似文献   
992.
Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill.  相似文献   
993.
摘要:今天的美国有1 400万的癌症存活者,其中的很多存活者中都接受了多种治疗,包括手术、放疗、化疗、靶向治疗等。这些治疗能够延长生存时间,但同时也会带来很多急慢性的副作用,危害健康,影响生活质量。体力活动(PA)与癌症生存这一领域发展迅速,主要研究PA对癌症患者的影响。基于该领域的研究进展,提出了以下10大研究问题:1)PA能够降低癌症复发风险、和/或提高存活吗?2)PA能够影响癌症治疗决策、完成率、和/或患者对治疗的反应吗?3)癌症存活者的最佳运动处方是什么?4)静坐少动行为对癌症存活者有何影响?5)癌症存活者最有效的体力活动干预方案是什么?6)哪些癌症会影响病人对PA的反应?7)癌症存活者进行体力活动时需要注意的安全问题有哪些?8)哪些具体的癌症症状可以由PA解决?9)对于癌症晚期患者,体力活动还有何作用?10)如何将体力活动研究结果转化到临床和社区肿瘤实践中来?上述问题的回答至关重要,这不仅关系到体力活动和癌症存活这一研究领域的发展,更重要的是,能够为每年数百万新诊断为癌症的病人、正在接受癌症治疗的病人、治疗结束处于恢复中的病人或是那些正在与晚期癌症抗争的病人带来福音。  相似文献   
994.
This study examined cultural reflections online of audience comments on social network sites regarding vocal talent shows in China and the United States. The study applied dimensions of cross culture to investigate audience comments on the official social networking sites of The Voice of China and The Voice. Findings reflect Hofstede’s dimensions as applied to social media and illustrate how individuals alter their “local” cultural norms in the new media environment. The study specifically enhances the exploration of cultural manifestations in cyberspace, which fewer cross-cultural studies have researched.  相似文献   
995.
996.
Youjung Shin 《Minerva》2018,56(2):231-257
This paper aims to show the historical contingency of policy entrepreneurship in science by analyzing the case of brain research in South Korea during the last decade of the 20th century. This decade saw an increasing emphasis placed upon the development of information technology and its use for societal changes. The rise of the “Information Society” in Korea was an important context for shaping the field of brain research as an amalgam of multiple disciplines which led to the passage of the Brain Research Promotion Act; the first law in the world enacted to promote brain research. This paper, through focusing on in what context someone takes up an entrepreneurial role, shows how the concept of interdisciplinarity has been shaped by, and how it has influenced the development of brain research and its related policy measures in Korea. It ultimately reveals the contingent and transient aspect of a policy entrepreneur and his effect on building a new field.  相似文献   
997.
David Kaldewey 《Minerva》2018,56(2):161-182
This article analyzes the concept of “grand challenges” as part of a shift in how scientists and policymakers frame and communicate their respective agendas. The history of the grand challenges discourse helps to understand how identity work in science and science policy has been transformed in recent decades. Furthermore, the question is raised whether this discourse is only an indicator, or also a factor in this transformation. Building on conceptual history and historical semantics, the two parts of the article reconstruct two discursive shifts. First, the observation that in scientific communication references to “problems” are increasingly substituted by references to “challenges” indicates a broader cultural trend of how attitudes towards what is problematic have shifted in the last decades. Second, as the grand challenges discourse is rooted in the sphere of sports and competition, it introduces a specific new set of societal values and practices into the spheres of science and technology. The article concludes that this process can be characterized as the sportification of science, which contributes to self-mobilization and, ultimately, to self-optimization of the participating scientists, engineers, and policymakers.  相似文献   
998.
This paper examines the potential pitfalls for academic research associated with goal displacements in the implementation of goals and indicators of research commercialization. We ask why patenting has come to serve as the key policy indicator of innovative capacity and what consequences this has for the organization of academic research. To address these questions, the paper presents a case study from Denmark on, firstly, why and how the 1999 Danish ‘Act on Inventions’ introduced patenting as a central instrument to Danish science policy and, secondly, the effects the Act has had on Danish university organization and research practices. We trace why and how commercialization was introduced as an important objective in Danish science policy since the 1980s. The increased focus on patents is explained as an isomorphic adjustment to an international ‘science policy field,’ manifested in particular through OECD statistics, where patenting has come to serve as a key metric in international rankings. In a second step, we examine what effects the patenting requirements have had on organization and research practice at a Danish university. We show that in practice ‘number of patents’ changed from serving as an indicator of innovative capacity to being a policy goal in itself, thus in effect producing a goal displacement that is potentially damaging for both academic research and innovation capacity of the surrounding society. As a consequence of this goal displacement, active scientists now increasingly engage in patenting primarily as a means to fulfill organizational targets and to increase their ‘fundability,’ rather than to promote commercial applications of their research. In conclusion, we discuss how these unfulfilled policy ambitions have led to a retrospective redefinition of policy goals rather than an adjustment of the actual policy tools.  相似文献   
999.
In this paper, I analyze how recent calls to internationalize publication behavior affect research practices at an automotive engineering department in Germany. Automotive engineering is a field with traditionally rather scarce publication activity and strong connections to industry. Substantial authority to define suitable research problems and ways of organizing knowledge production on a daily basis was therefore reserved for local academic elites as well as corporate partners. However, as engineers are increasingly expected to prove their performance through publishing in international peer-reviewed journals, the judgment as to what should be considered “interesting” or “robust” research is partly relegated to a gradually globalizing community of academic peers. This generates a variety of tensions with established ways of coordinating epistemic work at the department studied here. For example, the thematic interests of journals tend to exert a disruptive centrifugal pull in the context of an otherwise highly modular research culture, and possibilities to publish in international venues are unequally distributed across individual research projects. But while department members agree that there is a lack of fit between current practices and new expectations towards their publishing behavior, their opinions about the conclusions that should be drawn differ significantly. Some researchers argue that profound organizational changes are necessary to foster the academic rigor of German engineering research. Others believe that evaluation criteria should simply be adapted. This situation is arguably characteristic for research areas with a traditionally strong orientation to local stakeholders, and it suggests a need for more deliberative, participatory approaches to research evaluation in such fields.  相似文献   
1000.
Marc Torka 《Minerva》2018,56(1):59-83
Funding is an important mechanism for exercising influence over ever more parts of academic systems. In order to do so, funding agencies attempt to export their functional and normative prerequisites for financing to new fields. One essential requirement for fundees is then to construct research processes in the form of a project beforehand, one that is limited in time, scope and content. This article demonstrates how the public funding of doctoral programs expands this model of project research from experienced academics to the socialization process for the new academic generation. This process of “projectification” underlies funding-driven institutional changes in doctoral training. A multi-level comparative study of German policies, funding mechanisms and organizational frameworks for doctoral training demonstrates the emergence of a specific model of predefined PhD projects. The investigation of doctoral training practices reveals that socio-epistemic preconditions regulate whether research fields adopted or rejected this demanding model. This result contradicts widespread claims about a radical change in doctoral training and suggests focusing on the actual practices of field-specific doctoral research.  相似文献   
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