Antioxidant response and oxidative damage induced by a swimming session: influence of gender

In this study, we examined oxidative stress after a swimming session, the responses of the antioxidant defences, and the influence of gender on these responses. Fifteen boys and eight girls participated voluntarily in the study. Plasma concentrations of 17-beta-estradiol, vitamin E, retinol, carotenes, ascorbate, malondialdehyde, and the carbonyl index were determined. Creatine kinase, gamma glutamyl transpeptidase, and lactate dehydrogenase activities, as well as glucose, urea, urate, cholesterol, and triglycerides, were determined in serum. Plasma concentrations of 17-beta-estradiol were higher in girls than in boys. Exercise increased plasma ascorbate both in boys and in girls. Malondialdehyde increased in boys but was maintained in girls after exercise. Creatine kinase values corrected for lean body mass were similar in boys and girls at baseline, but the post-exercise values in boys were higher than in girls. A positive correlation was observed in boys, but not in girls, between plasma malondialdehyde and creatine kinase corrected concentrations. Furthermore, a negative correlation was observed between the increase in circulating neutrophils and in creatine kinase activity in girls but not in boys. In conclusion, a swimming session induced higher muscular and oxidative damage in boys than in girls.     

Determinants and patterns of physical activity practice among Spanish university students

The purpose of the present study was to investigate the socio-demographic and lifestyle determinants of physical activity practice, as well as the motivations for being or not being physically active in Spanish university students. A representative sample of students from a Spanish university (n = 2,051; 42.1% males; mean age 21.9, s = 4.8 years) participated in the present cross-sectional study. A questionnaire including questions regarding lifestyle, dietary habits, parents' characteristics, and physical activity habits was administered to the students. The socio-demographic and lifestyle determinants of physical activity practice were assessed using multivariable logistic regression. 68.4% of men and 48.4% of women reported to practise physical activity in the present sample. Those who practised physical activity consumed more fruits and were less likely to be smokers compared to non-physically active students. Also, physically inactive men spent more time in front of the computer and physically inactive women spent more time in front of the TV and were more likely to be frequent alcohol consumers. Maternal educational level and maternal physical activity habits were also important determinants of physical activity practice among men and women respectively. In conclusion, physically active students tended to engage in other healthy habits in the present population, suggesting the clustering of healthy or unhealthy lifestyle factors among specific subgroups.     

What leads people to keep on e-learning? An empirical analysis of users' experiences and their effects on continuance intention

User retention is a major goal for higher education institutions running their teaching and learning programmes online. This is the first investigation into how the senses of presence and flow, together with perceptions about two central elements of the virtual education environment (didactic resource quality and instructor attitude), facilitate the user's intention to continue e-learning. We use data collected from a large sample survey of current users in a pure e-learning environment along with objective data about their performance. The results provide support to the theoretical model. The paper further offers practical suggestions for institutions and instructors who aim to provide effective e-learning experiences.     

Citizenship and Identity: The Self-Image of Secondary School Students in England and Catalonia

We discuss the ways in which English and Catalan students perceive themselves as members of communities and as citizens and the role of schools in these perceptions. Questionnaire and interview data were collected and analysed from 583 secondary school students in a total of 9 schools that were known for their commitment to citizenship education in England and Catalonia. The research took place when issues of national and other identities were prominently discussed in the media and elsewhere and when significant changes were being introduced in both locations regarding citizenship education as a specific curriculum subject and also in the wider context of education and schooling. Our results suggest that while the English students in our sample understand citizenship in terms of a subjective identification, our Catalan students perceive citizenship as a legal and externally assigned status. We did not intend to obtain nationally representative samples but rather to gain in-depth knowledge of the data and to discuss the implications of these results for the differing purposes of citizenship education. We make recommendations for how school-based citizenship education may contribute to current challenges related to citizenship and identities.     

Toward a Longitudinal Model of e-Commerce: Environmental,Technological, and Organizational Drivers of B2C Adoption

Despite the important benefits for firms of commercial initiatives on the Internet, e-commerce is still an emerging distribution channel, even in developed countries. Thus, more needs to be known about the mechanisms affecting its development. A large number of works have studied firms' e-commerce adoption from technological, intraorganizational, institutional, or other specific perspectives, but there is a need for adequately tested integrative frameworks. Hence, this work proposes and tests a model of firms' business-to-consumer (called B2C) e-commerce adoption that is founded on a holistic vision of the phenomenon. With this integrative approach, the authors analyze the joint influence of environmental, technological, and organizational factors; moreover, they evaluate this effect over time. Using various representative Spanish data sets covering the period 1996–2005, the findings demonstrate the suitability of the holistic framework. Likewise, some lessons are learned from the analysis of the key building blocks. In particular, the current study provides evidence for the debate about the effect of competitive pressure, since the findings show that competitive pressure disincentivizes e-commerce adoption in the long term. The results also show that the development or enrichment of the consumers' consumption patterns, the technological readiness of the market forces, the firm's global scope, and its competences in innovation continuously favor e-commerce adoption.     

Vitamin C supplementation does not influence plasma and blood mononuclear cell IL-6 and IL-10 levels after exercise

Abstract

The aim of this study was to determine whether the highest vitamin C supplementation associated with complete bioavailability influences the plasma and blood mononuclear cell IL-6 and IL-10 response to exercise. A double-blinded study of supplementation with vitamin C was performed. After 15 days of supplementation with vitamin C (500 mg · day^?1, n = 16) or a placebo (n = 15), participants in the study completed a 15-km run competition. Blood samples were taken before and after competition. Oxidative stress markers, antioxidants, cortisol, IL-6 and IL-10 were determined in plasma or serum. IL-6 and IL-10 protein and mRNA levels were measured in blood mononuclear cells. Although higher plasma and blood mononuclear cell vitamin C levels were observed in the supplemented group when compared with the placebo one, the two groups showed identical exercise-induced changes in all the measured parameters. Exercise induced increased IL-6 and IL-10 levels in plasma and blood mononuclear cells. IL-6 and IL-10 mRNA levels in blood mononuclear cells increased after the competition. After recovery, IL-6 mRNA returned to basal levels and IL-10 mRNA levels remained elevated. In conclusion, exercise induced increased IL-6 and IL-10 production in blood mononuclear cells. However, vitamin C supplementation did not influence IL-6 and IL-10 response to exercise.     

Professionalism And Technocracy: Esteve Terradas And Science Policy In The Early Years Of The Franco Regime

At the peak of his career, Esteve Terradas (1883–1950) played a major role in the science and technology policy of the Franco regime. Supervising the creation of a new aeronautical centre and a state electrical company, he developed a liberal programme under an authoritarian regime. This paper explores the development and intersection of his private and public lives.     

Cross-cultural comparisons of child-reported emotional and physical abuse: rates, risk factors and psychosocial symptoms

OBJECTIVES: This study was designed to assess the incidence of child emotional and physical abuse, associated risk factors and psychosocial symptoms in a cross-cultural comparison between post-communist bloc countries. Method: One-thousand one-hundred forty-five children ages 10-14 from Latvia (N = 297), Lithuania ( N = 300), Macedonia (N = 302), and Moldova (N = 246) participated in the study. They completed questionnaires assessing their experience of emotional or physical abuse, and provided information about family risk-factors and psychosocial symptoms, including PTSD-related symptoms. RESULTS: Incidence rates of maltreatment differed by country, as did levels of reported psychosocial symptoms. Incidence of emotional and physical abuse differed by region, with higher levels of abuse reported in the rural regions. In all four countries, a similar association between emotional/physical abuse and psychosocial symptoms was found, with the uniformly largest correlation between emotional abuse and anger. When examining the combined scores of emotional and physcial abuse, even higher correlation's were found, particularly in relation to anger and depression. In all four countries, parental overuse of alcohol was associated with emotional and/or physical abuse. CONCLUSIONS: Findings show differences by country in child-reported levels of emotional and physical abuse, but similar patterns of correlation with psychosocial symptoms and the risk factors of parental alcohol overuse and living in a rural area.