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This study investigated the acute endocrine responses to a 164-km road cycling event in a hot environment. Thirty-four male experienced cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm) participating in a 164-km road cycling event were recruited. Blood samples were collected within 0.3–2.0 h before the start (PRE: ~0500–0700 h) and immediately following the ride (POST). Samples were analysed for testosterone, growth hormone (GH), cortisol and interleukin-6 (IL-6). The temperature and humidity during the event were 35.3 ± 4.9°C and 47.2 ± 14.0%, respectively. Based on the finishing time, results for the fastest (FAST, 305 ± 10 min) and the slowest (SLOW, 467 ± 31 min) quartiles were compared. At POST, testosterone concentration was significantly (P < 0.05) lower (PRE, 20.8 ± 8.6; POST, 18.2 ± 6.7 nmol · L?1), while GH (PRE, 0.3 ± 0.1; POST, 2.3 ± 0.3 µg · L?1), cortisol (PRE, 661 ± 165; POST, 1073 ± 260 nmol · L?1) and IL-6 (PRE, 4.0 ± 3.4; POST, 22.4 ± 15.2 pg · mL?1) concentrations were significantly higher than those at PRE. At POST, GH and cortisol were significantly higher for the FAST group than for the SLOW group (GH, 3.6 ± 2.0 and 1.0 ± 0.8 µg · L?1; cortisol, 1187 ± 209 and 867 ± 215 nmol · L?1). Participation in an ultra-endurance road cycling event in a hot environment induced significant acute changes in concentrations of circulating hormones, with a greater augmentation of GH and cortisol in those completing the ride fastest.  相似文献   
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Extracting policy-relevant information from large national surveys of educational achievement is ordinarily a nontrivial task. It is made more treacherous when the data are expressed on scales that are not uniquely determined. The paper begins with a critical analysis of a recent attempt to interpret the findings on reading achievement obtained by the National Assessment of Educational Progress (NAEP). It then describes a new approach to the quantification and interpretation of change and demonstrates its appropriateness for repeated cross-sectional designs such as NAEP. Limitations imposed by the survey design and the nature of the measurements are highlighted  相似文献   
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We conducted surveys of adults participating in municipally sponsored volunteer events in the Portland, OR metropolitan area in order to understand the range of attitudes and behaviors associated with volunteer work. We sampled 172 individuals in 18 events from February to June 2012. Principal components and factor analyses of survey responses identified three groups based on annual frequency of participation in stewardship events: first-time volunteers, mid-level volunteers (3–10 events per year), and frequent volunteers (>10 events per year). Our analyses revealed three main factors that explained the variation in survey response for the three volunteer groups: environmental identity, private pro-environmental behavior, and civic engagement. All three factors were positively correlated with frequency of participation in stewardship events, with the most frequent volunteers indicating the highest degree of attention to environmental issues, environmental identity, and self-reported pro-environmental behaviors. Frequent volunteers were more likely to feel personally attached to their local environment, believe that their efforts help solve environmental problems, and enjoy being part of community efforts. These results suggest that stewardship activities provide opportunities for volunteers to interact with others while working collectively toward restoring and maintaining parks, which may contribute to more resilient communities.  相似文献   
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In the time between its founding and the fall of the wall in November 1989, more than three million people left the German Democratic Republic, many of them illegally and under dangerous circumstances. The party leadership perceived this mass exodus of its citizens as one of the major threats for the real socialist regime.1?1. Bispinck Bispinck, Henrick. “Republikflucht. Flucht und Ausreise als Problem der DDR-Führung.” Vor dem Mauerbau. Politik und Gesellschaft der DDR in den Fünfziger Jahren, edited by MichaelSchwartz and Hermann Wentker, 285309. München: Oldenbourg Wissenschaftsverlag, 2003. [Google Scholar], “Republikflucht.”‘Republikflucht’, as this move from East to West was called by the party leadership, was the reason for the two most important hiatuses in Eastern German history: the first result was that the SED leadership built the wall in August 1961. Many years later, in the fall of 1989, the situation culminated, when a flood of desperate refugees tried to escape to the Federal Republic of Germany via Hungary, Poland and Czechoslovakia, thus effectively hurrying along the regime's demise. The world of sports, too, was considerably affected by this phenomenon. The following essay shall offer a short historical summary of the different reasons and routes Eastern German top athletes chose for their escape. Examples from various decades show that in spite of individual circumstances certain similarities in pattern can be made out, especially in respect to the way the government dealt with these cases of ‘treason’.  相似文献   
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Demand is a major potential source of innovation, yet the critical role of demand as a key driver of innovation has still to be recognised in government policy. This article discusses public procurement as one of the key elements of a demand-oriented innovation policy. The paper starts by signaling the new significance of public procurement for innovation policy strategies at the EU level and in a range of European countries. It then defines the concept of public procurement and embeds this concept within a taxonomy of innovation policies. The rationales and justifications of public procurement policies to spur innovation are discussed, followed by a consideration of the challenges and potential pitfalls as well as appropriate institutional arrangements and strategies, including some recent empirical examples of good practice. It concludes by confronting the public procurement approach with two of the most common objections to it and by considering future prospects.  相似文献   
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Educational technology research and development - E-learning opportunities have become an increasingly important component of university education. Various laboratory studies have shown that...  相似文献   
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