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111.
Endurance running performance in athletes with asthma 总被引:1,自引:0,他引:1
Laboratory assessment was made during maximal and submaximal exercise on 16 endurance trained male runners with asthma (aged 35 +/- 9 years) (mean +/- S.D.). Eleven of these asthmatic athletes had recent performance times over a half-marathon, which were examined in light of the results from the laboratory tests. The maximum oxygen uptake (VO2max) of the group was 61.8 +/- 6.3 ml kg-1 min-1 and the maximum ventilation (VEmax) was 138.7 +/- 24.7 l min-1. These maximum cardio-respiratory responses to exercise were positively correlated to the degree of airflow obstruction, defined as the forced expiratory volume in 1 s (expressed as a percentage of predicted normal). The half-marathon performance times of 11 of the athletes ranged from those of recreational to elite runners (82.4 +/- 8.8 min, range 69-94). Race pace was correlated with VO2max (r = 0.863, P less than 0.01) but the highest correlation was with the running velocity at a blood lactate concentration of 2 mmol l-1 (r = 0.971, P less than 0.01). The asthmatic athletes utilized 82 +/- 4% VO2max during the half-marathon, which was correlated with the %VO2max at 2 mmol l-1 blood lactate (r = 0.817, P less than 0.01). The results of this study suggest that athletes with mild to moderate asthma can possess high VO2max values and can develop a high degree of endurance fitness, as defined by their ability to sustain a high percentage of VO2max over an endurance race. In athletes with more severe airflow obstruction, the maximum ventilation rate may be reduced and so VO2max may be impaired. The athletes in the present study have adapted to this limitation by being able to sustain a higher %VO2max before the accumulation of blood lactate, which is an advantage during an endurance race. Therefore, with appropriate training and medication, asthmatics can successfully participate in endurance running at a competitive level. 相似文献
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Outsourcing is a complex, controversial and pervasive practice that is increasingly becoming a matter of concern for educational researchers. This article contributes to this literature by examining outsourcing practices related to health, sport and physical education (HSPE). Specifically, it reports data on specialist health and physical education (HPE) teachers', principals' and external providers' reasons for participating in outsourcing arrangements. These data were obtained from a collective case study of six schools and the external providers that they outsourced HSPE to over a 12-month period, using semi-structured interviews and overt participant observations. The findings illustrate the ways in which the informants explained their outsourcing practices using a variety of educationally and organisationally oriented reasons. Educational value, human resources (e.g. expertise), physical resources (e.g. facilities) and symbolic resources (e.g. status) were reasons for outsourcing HSPE that were commonly cited by principals and specialist HPE teachers. Among external providers, educational value, income generation and promotion/advertising were frequently cited to explain their work with and for schools. These findings illustrate the ways in which outsourcing practices in HSPE articulate with, and are implicated in, broader educational privatisations. They also highlight the boundaries that outsourcing practices trouble or reinforce, such as those marking the purview of markets, membership of the HPE profession and the constitution of expertise. 相似文献
115.
Jason R. Sattizahn Daniel J. Lyons Carly Kontra Susan M. Fischer Sian L. Beilock 《Mind, Brain, and Education》2015,9(3):164-169
Student difficulties in science learning are frequently attributed to misconceptions about scientific concepts. We argue that domain‐general perceptual processes may also influence students' ability to learn and demonstrate mastery of difficult science concepts. Using the concept of center of gravity (CoG), we show how student difficulty in applying CoG to an object such as a baseball bat can be accounted for, at least in part, by general principles of perception (i.e., not exclusively physics‐based) that make perceiving the CoG of some objects more difficult than others. In particular, it is perceptually difficult to locate the CoG of objects with asymmetric‐extended properties. The basic perceptual features of objects must be taken into account when assessing students' classroom performance and developing effective science, technology, engineering, and mathematics (STEM) teaching methods. 相似文献
116.
Ruth F.G. Williams 《普罗米修斯》2015,33(4):421-430
Dissent and assent contribute to new information and knowledge in that they foster ideas, avert errors and counter misplaced beliefs. Although intended to facilitate progress, innovation and creativity, dissent may be opposed by the closed mind and defensive mindset. Don Lamberton encountered a specific mindset in his own duties to scholarship in economics. Thus, the perspective of dissent is a fitting way to pay homage to his scholarship. However, this paper is also a lament. It gives an interpretation of Antigone from political philosophy which depicts Antigone rocking an ideological boat harboured by the polis. The silencing of Antigone’s voice results in unexpected losses in the oikos. This is the sort of tragedy threatening critical and innovative scholarship in the twenty-first century. 相似文献
117.
Penetration of Nigerian predatory biomedical open access journals 2007–2012: a bibliometric study
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This paper presents the bibliometric characteristics of 32 biomedical open access journals published by Academic Journals and International Research Journals – the two Nigerian publishers in Jeffery Beall's list of 23 predatory open access publishers in 2012. Data about the journals and the authors of their articles were collected from the websites of the publishers, Google Scholar and Web of Science. As at December 2012, the journals had together produced a total of 5,601 papers written by 5,599 authors, and received 12,596 citations. Authors from Asia accounted for 56.79% of the publications; those from Africa wrote 28.35% while Europe contributed 7.78%. Authors from Africa accounted for 18.25% of the citations these journals received, and this is about one‐third the number of citations by authors in Asia (54.62%). At country level, India ranks first in the top 10 citer countries, while Nigeria, the host country of the journals, ranked eighth. More in‐depth studies are required to develop further information about the journals such as how much scientific information the journals contain, as well as the science literacy of the authors and the editorial. 相似文献
118.
This study employs issue ownership theory to examine the partisan dynamics surrounding the idea of American exceptionalism in presidential discourse. We conducted a content analysis of invocations of American exceptionalism in all major U.S. presidential addresses—domestic and foreign—from the end of World War II through Trump’s 1st year in office. We find that even though Republicans have traditionally claimed ownership of American exceptionalism, patterns in presidential discourse tell a very different story. Specifically, our results show (a) in domestic contexts, Republican and Democratic presidents were very similar in their invocations of American exceptionalism during the Cold War but that Democrats have held a substantial advantage over Republicans throughout the post–Cold War era, including on issue areas that Republicans are perceived to “own” (e.g. national security); (b) in foreign contexts, Democrats have been much more outspoken in their embrace of American exceptionalism throughout both the Cold War and post–Cold War; and (c) President Trump has diverged significantly, both in substance and frequency, from his Democratic and Republican predecessors in his invocation of American exceptionalism. We reflect on the implications of these findings on our broader understanding of issue—and trait—ownership, presidential discourse, and American exceptionalism in American politics. 相似文献
119.
Homemade PowerPoint games are a low-tech alternative for using game design in classrooms. To date, much of the research examining the games has not shown an improvement in performance. This has led some to question whether the games are properly aligned with the instructional strategies researchers have used as justifications to support using them. This study examined how increasing the structure of the game design project affected student performance when compared to control groups, as well as those who created games in previous iterations of the study. In addition, we examined the effects of student performance when two of the instructional strategies (microtheme writing and question writing) were tested in isolation. Most of the comparisons showed no statistical difference in performance; however, results from the final iteration yielded significant gains when compared to the control group. 相似文献
120.
Michelle Pannor Silver N. Celeste Pang Sarah A. Williams 《Educational gerontology》2015,41(5):333-347
For individuals with strong work identities, the decision to retire can be particularly challenging. For academic physicians, retirement is an important personal decision that also has far-reaching implications for the healthcare system. This is because academic physicians are responsible for producing the research from which key medical decisions are made, for training future healthcare providers, and for providing specialized care for patients. For this study, we conducted focus groups with academic physicians from a large research university in Canada and then performed inductive thematic analyses to examine perceptions and concerns about later life career transitions. This study highlights tensions between professional experiences for the next generation of physicians and individual struggles with personal identity. Findings suggest improvements to institutional programs that support flexible, agentive, and respectful retirement transitions will not only be beneficial but necessary as medical and university systems continue to grapple with issues of balanced recruitment and succession. 相似文献