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31.
Abstract

Runners have increased numbers of neutrophils in the airways at rest and after exercise compared with sedentary individuals. The aim of this study was to determine whether Mediterranean seasonal changes in temperature, humidity or airborne pollutants affect the airway cells of runners training outdoors in an urban environment. In nine male amateur runners, cell composition, apoptosis, and inflammatory mediators were measured in induced sputum collected at rest (baseline) and the morning after races held in the fall (21 km), winter (12 km), and summer (10 km). Concentrations of air pollutants were below the alert threshold at all times. Neutrophil differential counts tended to increase after all races (P = 0.055). Apoptosis of neutrophils increased with ozone (P < 0.005) and particulate matter <10 μm (PM10) (P < 0.05) exposure. Bronchial epithelial cell counts were low at all times and weakly correlated with ozone and PM10 concentrations. Apoptotic bronchial epithelial cells increased after all races (P < 0.05). Inflammatory mediators in induced sputum were low at baseline and after the races, and correlated with neutrophil differential counts only at rest. In conclusion, apoptosis of airway cells in runners appears to be affected by both exercise and environmental conditions. Apoptosis of neutrophils increased with exposure to environmental pollutants while apoptosis of bronchial epithelial cells increased after intense exercise. Since no relationship was observed between neutrophil counts and inflammatory mediators 20 h after races, airways inflammation at this time point appears blunted in healthy runners and little affected by exposure to mild seasonal changes and airborne pollutants.  相似文献   
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An important question that must be answered is whether cognitive styles, abilities, and aptitudes provide complementary or redundant information regarding students' characteristics. Measures of 6 styles, 6 abilities, and 12 aptitudes were administered to 201 Navy recruits. Relationships among all cognitive attributes and between sets of styles and abilities as well as styles and aptitudes were examined by computing product-moment correlations and two canonical analyses. A principal-factor analysis and varimax rotation were also computed for all 24 characteristics. The results indicated that many styles are significantly related to abilities and aptitudes. However, the amount of shared variance between styles and abilities or aptitudes is small. Three significant factors were extracted (i.e., technical aptitude, verbal ability, and general problem solving) which underlie much of the variability of these cognitive characteristics. The data demonstrated (1) the relative dependence of most cognitive styles with abilities and aptitudes inherent to general problem solving, and (2) the relative independence of some cognitive styles from technical aptitude and verbal ability dimensions.  相似文献   
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研究目的:研究方法:通过有限元分析和极限分析,研究了在纵向和横向载荷下钢框架的最大负荷和坍塌模式,并考虑了塑性铰链住轴向力和弯曲力矩的作用下住实际旋转时的运动学。在垂直和水平方向载荷共存的情况下,基于轴向力和弯曲力矩的交互作用,研究延性框架的极限载荷和坍塌模式对产生于塑性铰链的真实运动学的敏感性。通过两个基本的案例和通过成功地评估非线性有限元分析和直接实施的极限分析步骤,并利用MATHEMATICA,揭示了其敏感性。 在标准规程的框架下,即使在最简单的案例中,极限分析的主要结果也会考虑在坍塌时的运动学,这与设计和加固的目的都是相关的。如果没有对所有的结构元件的轴向力和弯曲力矩的交互作用进行合理的计算,塑性铰链的定位计算可能得出不正确的坍塌机理和误导性的安全系数。就具体方面而言,本文清楚地表明,在设计新的结构或者为现有结构进行加固时,即使是使用看起来已经非常完备的经典步骤,也必须非常小心。本文的模型可以为处理规程设计的执业工程师和标准化委员会提供参考。  相似文献   
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Multiple individual and neighbourhood characteristics are theorised to influence adult sedentary behaviour. The aim of this study was to examine associations between individual and neighbourhood-level characteristics in 40 deprived neighbourhoods in London, UK. A cross-sectional design was utilised with baseline data from the Well London Cluster Randomised Controlled Trial in 40 deprived neighbourhoods in London. Multilevel linear regression was used to examine associations between individual characteristics (measured by household survey), neighbourhood characteristics (neighbourhood audit, GIS and routinely available datasets) and sedentary behaviour (sitting time). Individual-level positive mental well-being and health behaviours were associated with sedentary time. Individual-level social networks were associated with decreased sedentary time in men and increased sedentary time in women. Neighbourhood-level measures of social networks and perceived neighbourhood quality were associated with reduced sedentary time. Fifteen per cent of the variance in sedentary time was attributable to differences at the neighbourhood level (intra-class correlation coefficient?=?0.15). These findings suggest that social networks at the individual and neighbourhood levels, collective perceptions of neighbourhood quality, individual-level positive mental well-being and other health behaviours may be important components of interventions developed to reduce sedentary time in deprived populations.  相似文献   
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Governments and public agencies are increasingly keen to support the translation of scientific discoveries into commercial and societal applications through science valorisation funding, as a way to enhance progress and inclusive growth. In this paper, we use grant-level data from the European Research Council Proof-of-Concept (PoC) programme, in order to assess the impact of public funding on a broad set of science valorisation outcomes, including licensing, spinoff formation, R&D collaborations, consulting and access to follow-on funding. We employ an instrumental variable approach to compare the valorisation outcomes of projects that obtained an ERC PoC grant to a group of projects that applied to the PoC scheme but were not funded. We find that the programme was effective in fostering the early valorisation of scientific discoveries by all measures of success that we employed. Overall, thus, our findings speak in favour of this type of policy instrument as a catalyst to accelerate the transition of scientific breakthroughs towards practical applications.  相似文献   
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Two different analytical approaches have been taken into account to investigate the role of Si-rich phases in enhance hydraulic reactions of bedding mortar mixtures from San Lorenzo Church in Milan (Northern Italy) and from the Medicean Aqueduct in Pisa (Central Italy). In the first case, mortars show clear hydraulic type reactions in the form of coronal layers between the reacting additive and the binder mass. In the second one, the hydraulic reactions do not develop visible mineral phases and processes have been inferred from chemical, mineralogical analyses and mass balance calculation. The microstructural studies not always are sufficient to understand the complex dynamics of reaction attained during pre-industrial manufacturing processing of mortars and related binders. In fact, if the reacting raw materials are fine-grained and/or have remarkable chemical reactivity, no relicts are preserved by mortar microtextures.  相似文献   
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Research in Higher Education - This study provides comparable lower-bound estimates of inequality of opportunity for tertiary education (EIOp) for 31 countries in Europe, by using the two EU-SILC...  相似文献   
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