Pre-exercise antioxidant enzyme activities determine the antioxidant enzyme erythrocyte response to exercise     

Tauler P  Aguiló A  Guix P  Jiménez F  Villa G  Tur JA  Córdova A  Pons A 《Journal of sports sciences》2005,23(1):5-13

Free radical production increases during exercise and oxidative damage occurs in several tissues. We examined the effects of three different exercise tests on the pattern of change of erythrocyte enzyme antioxidant activities. The tests were a short maximal exercise test, a submaximal prolonged exercise test and a cycling stage during competition. The participants were amateur and professional cyclists with different training statuses and different basal erythrocyte antioxidant enzyme activities. The maximal test produced no changes in the erythrocyte antioxidant enzyme activities of amateur sportsmen. The submaximal test, performed at 80% of maximal oxygen uptake, decreased erythrocyte catalase (12%), glutathione peroxidase determined with H2O2 (14%) and glutathione reductase (16%); superoxide dismutase activity increased by about 25%. The cycling stage performed by professional cyclists increased erythrocyte catalase (29%) and glutathione reductase (10%) activities. The in vivo changes in glutathione reductase activity were confirmed by in vitro measurements: hydrogen peroxide decreased and the presence of catalase increased the activity of this enzyme. In conclusion, we suggest that the different erythrocyte antioxidant enzyme responses to diverse exercise tests can be explained by the effects of hydrogen peroxide and the superoxide anion on the antioxidant enzyme activities in erythrocytes.  相似文献   

Children,stress, and context: integrating basic,clinical, and experimental prevention research     

Brotman LM  Gouley KK  Klein RG  Castellanos FX  Pine DS 《Child development》2003,74(4):1053-1057

Findings from the Watamura, Donzella, Alwin, and Gunnar (this issue) study support the growing recognition of the importance of context on physiology and affective and behavioral regulation early in human development. This discussion focuses on the role of context and development on hypothalamic-pituitary-adrenal (HPA) axis regulation in young children. Discussed in this article are the Watamura et al. findings with regard to relevant animal studies, extension of these observations to samples of children at elevated risk for psychopathology, and experimental prevention studies with young children. It is contended that environmental factors operating at key points in development may shape affective and behavioral regulation as well as HPA axis function in children, much as environmental factors have been shown to shape HPA axis regulation in animals.  相似文献   

Acculturation and consumption: Textures of cultural adaptation     

Mark Cleveland  Michel Laroche  Frank Pons  Rony Kastoun 《Int J Intercult Relat》2009,33(3):196-212

This study examines patterns of cultural adaptation of an ethnic minority as manifested in consumption of traditional ethnic and mainstream culture foods. A survey, containing multiple measures of several ethnic identification and acculturation dimensions, along with consumption frequencies of both traditional and mainstream culture foods, was administered to a sample of ethnic Lebanese residing in a predominately French-speaking urban area. The results confirm that ethnic identity and acculturation are distinct processes, providing strong support for dual process models of cultural adaptation. A series of structural equation models linking the twin cultural influences to the consumption of traditional home and mainstream host food categories found little support for the linearity assumption between cultural adaptation and consumption behavior. Rather, the relationship between ethnic identity, acculturation, and consumption behaviors appears to be far more complex, and specific to the food category under consideration. Mapping these patterns of cultural adaptation, we articulate a new typology, relating the extent and particular combinations that home and host cultural influences impact consumption behavior.  相似文献   

Fans,bloggers, and gamers: Exploring participatory culture     

Jean-Baptiste Harguindéguy  Xavier Coller 《Cultural Trends》2015,24(1):104-106

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The Origins of Football in Spain: From the First Press Appearance to the Constitution of the First Clubs (1868–1903)     

Xavier Torrebadella-Flix  Javier Olivera-Betrán 《国际体育史杂志》2017,34(7-8):471-497

This research focuses on the origins of football in Spain and seeks to show how and where it was introduced in the country, to comprehend the historical context, and to understand why it took roots so rapidly despite the rivalry with the well-established tradition of bullfighting. The period of study spans from 1868 (first news piece on football in Spain) to 1903 (celebration of the first football championship in the country). The methodology focused primarily on identifying the primary sources and selecting the secondary sources, followed by the interpretative analysis and the mapping of football associations created in Spain in the sport’s early days. The large urban cities led the process of creating football clubs from 1889: Barcelona (61), Madrid (15), and Bilbao (9) steered the process of legitimization and institutionalization of football in the country. In the last 11 years of the nineteenth century (1889–1899), 29 clubs were created in 12 different cities. In the first four years of the twentieth century (1900–1903), a further 103 clubs mushroomed all over the country. Thus a total of 132 clubs were founded between 1889 and 1903 in Spain, which laid the necessary foundations for the implantation and legitimization of football.  相似文献   

The influence of wearing ski-boots with different rigidity characteristics on postural control     

Frédéric Noé  Xavier García-Massó  Pauline Delaygue  Audrey Melon  Thierry Paillard 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(2):157-167

Abstract

External supports that reduce ankle joint mobility such as ski-boots can impair postural control of healthy participants. Although this disruptive effect has been attributed to the rigidity of the external supports, the results remained controversial and no study has been conducted in order to evaluate the influence of ski-boots rigidity. Hence, the question about the influence of ankle support rigidity on postural control remains open. This study was therefore undertaken in order to investigate the effect of ski-boots rigidity on postural control. Ten healthy active participants were recruited. The wearing of soft and rigid ski-boots was compared to barefoot while standing on a seesaw generating mediolateral and anteroposterior instability. Centre of pressure displacements were sampled with a force platform. The surface electromyographic activity of the main muscles from the leg, thigh and trunk was recorded. A motion analysis system was also used to calculate the ankle, knee and hip angles. The results did not reveal any negative influence of ski-boot rigidity on postural control but rather suggest a less active postural control with the rigid ski-boots which offered a higher mechanical contribution.  相似文献   

Pedagogising poverty alleviation: a discourse analysis of educational and social policies in Argentina and Chile     

Xavier Rambla  Antoni Verger 《British Journal of Sociology of Education》2012,33(6)

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In vitro evaluation of a program for machine-aided indexing     

Christian Jacquemin  Batrice Daille  Jean Royaut  Xavier Polanco 《Information processing & management》2002,38(6)

This article presents the human evaluation of ILIAD, a program for machine-aided indexing (MAI). It consists of two language engineering modules and is designed to assist expert librarians in computer-aided indexing and document analysis. Our aim is the expert evaluation of automatic multi-word term indexing. Evaluation is performed by documentary engineers. Cataloging and indexing are their principal tasks. They also have a good scientific knowledge of the domain to which the indexed documents belong.We first present the ILIAD program and the two systems submitted to this evaluation, the methodology (protocol) adopted, the differences between the protocol and the implementation, and the results of these evaluations. Human evaluation is divided into three parts: firstly the evaluation of controlled indexing, then free indexing and finally term variant extraction performed during controlled indexing. Finally, we analyze the relevance of this evaluation by calculating the agreement frequency and the Kappa coefficient and propose some future developments.  相似文献   

Broadband Utilization in Space: Effects of Population and Economic Structure     

Jacint Jordana  Xavier Fernández  David Sancho  Yanina Welp 《The Information Society》2013,29(5):341-351

We examine the effect of public policy on the growth of Internet use. Using a decentralized country—Spain—as an example, we compare the 17 Spanish regions to test different Internet policy designs, taking into account the quality and number of specific programs promoted by regional governments, as well as the presence or absence of strategic planning in each region. We treat the percentage of Internet users as a dependent variable to compare its diffusion in different territories. Our findings show that educational levels and economic differences explain about half of the variations observed. Furthermore, the regional policies play a significant role in explaining regional variations. We investigate which public policy instruments are more significant for the development of the Internet, and find that focused policy intervention and complex policy initiatives are more significant than other policy instruments in explaining the increase in the percentage of Internet users.  相似文献   

No Umpires in This Game: The Victorian Football League During Two World Wars,by Bruce Coe and Bruce Kennedy     

Xavier Fowler 《国际体育史杂志》2013,30(11):1200-1202

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