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61.
62.
The psychobiological status of cyclists over a period of 8 months of training was assessed by measuring the sympatho-adrenal level, the central noradrenergic activity, and the cortisol-testosterone ratio status noninvasively. Alteration of these indices after a large increase in training load lasting 4 days (+ 187%) was also examined. Urinary excretion of methoxyamines (metanephrine, normetanephrine) and 3-methoxy-4-hydroxyphenylglycol sulphate (MHPG-S), and salivary concentrations of cortisol and testosterone, were measured in 12 national cyclists after a non-specific training period and 48 h before 4 days of increased training (T1), after these 4 days (T2) and at the end of 4 months of specific training (T3). Urinary and salivary samples were also collected during a rest period (T0). At each of these times, mood states and ratings of perceived muscle soreness were assessed, and a questionnaire of early clinical symptoms of the overtraining syndrome (Profile of Mood States) was administered. A significant increase in normetanephrine (P < 0.05) and a decrease in the testosterone-cortisol ratio (P < 0.05) were observed at T2, while MHPG-S excretion remained unchanged. Over the same periods, increased training loads did not induce mood disturbances. Eight months of training were associated with significant alterations in metanephrine (P < 0.05) and MHPG-S (P < 0.05). These results suggest a dissociation between the neural and endocrine catecholaminergic components systems. Opposite responses between MHPG-S and Profile of Mood States scores show that further investigations are needed to understand the relationship between central noradrenergic function, which is recognized as a regulatory factor of mood, and psychological tests measuring mood. 相似文献
63.
The aim of this study was to determine whether there is an effect of time of day on the adaptation to strength training at maximal effort. Fourteen participants took part in this experiment. Their peak anaerobic power (Wingate anaerobic test) and peak knee extension torque at six angular velocities (1.05, 2.10, 3.14, 4.19, 5.24 and 6.29 rad x s(-1)) were recorded in the morning (between 07:00 and 08:00 h) and in the evening (between 17:00 and 18:00 h) just before and 2 weeks after a 6 week course of regular training. Seven of them trained only in the morning and seven only in the evening. Multivariate analysis of variance revealed a significant group x pre-/post-training x time of day interaction effect for peak torque and peak anaerobic power. Before training, in both groups, peak torque and peak anaerobic power were significantly higher in the evening than in the morning. After training, there was no significant difference in peak torque and peak anaerobic power between the morning and the evening for the morning training group. In contrast, in the evening training group, peak torque and peak anaerobic power were higher in the evening than in the morning. As a result of training, both peak torque and peak anaerobic power increased from their initial values as expected. The morning training group improved their peak anaerobic power significantly in the morning and in the evening, the absolute increase being larger in the morning than in the evening. The evening training group did not improve their peak anaerobic power in the morning, whereas it improved significantly in the evening. Although peak torque was significantly improved by training in the morning and evening in both groups, the absolute increase was greater in the morning than in the evening in the morning training group, whereas the opposite was the case for the evening training group. These results suggest that training twice a week at a specific hour increases the peak torque and the peak anaerobic power specifically at this hour and demonstrates that there is a temporal specificity to strength training. 相似文献
64.
Many eco-innovations have been linked to technical change in the ICT domain. Leveraging the distinctive features of general purpose technologies, ICT have the potential to steer green growth and to help decouple this growth from ecological damage. The paper aims to shed light on innovation dynamics in this emerging sector by investigating the patterns of innovation in the green ICT domains using granted EPO patent data from 1986 to 2006. By means of a network analysis, it identifies existing green ICT domains and examines the characteristics of innovative activity in these domains, focusing in particular on growth and technological pervasiveness, as well as on the variety of innovators. Results indicate that the innovative activity in green ICT domains is characterised by high growth and high levels of technological pervasiveness, considerable entry of new innovators and a variety of actors – with a prevalence of large ICT firms and universities. However, the analysis highlights the existence of three different clusters – emerging fields, established fields and mature fields – that are defined by different structures of innovative activities and by different technological opportunities. 相似文献
65.
We draw upon transformational leadership theory to develop an instrument to measure transformational parenting for use with adolescents. First, potential items were generated that were developmentally appropriate and evidence for content validity was provided through the use of focus groups with parents and adolescents. We subsequently provide evidence for several aspects of construct validity of measures derived from the Transformational Parenting Questionnaire (TPQ). Data were collected from 857 adolescents (M(age) = 14.70 years), who rated the behaviors of their mothers and fathers. The results provided support for a second-order measurement model of transformational parenting. In addition, positive relationships between mothers' and fathers' transformational parenting behaviors, adolescents' self-regulatory efficacy for physical activity and healthy eating, and life satisfaction were found. The results of this research support the application of transformational leadership theory to parenting behaviors, as well as the construct validity of measures derived from the TPQ. 相似文献
66.
We survey more than twenty studies estimating rates of return of investments in single art objects and whole collections and evaluate the various approaches to art price movements taken so far. The majority of the estimates find lower returns for investments in art objects than for investments in financial assets. However, most existing analyses are restricted to auction data and neglect transactions cost and taxation. They partly focus on mechanistic calculations and disregard the distinguishing institutional and behavioral characteristics of art markets. We look into the possibilities to capture and empirically estimate psychic returns from owning art. 相似文献
67.
Elefthrios Sapsalis Bruno van Pottelsberghe de la Potterie Ran Navon 《Research Policy》2006,35(10):1631-1645
This paper compares corporate and academic patents and tests whether they have similar value distributions and share common determinants of value. The empirical results based on an in-depth analysis of 400 biotech patents applied for by Belgian universities and firms lead to the following observations: (i) academic and corporate patent value distributions have similar levels of ‘skewness’; (ii) the identification of the institutional origin of knowledge allows for an improved understanding of the value determinants and (iii) there is a need to stimulate star scientists to codify their tacit knowledge into valuable patents. 相似文献
68.
Chrysanthi Kadji-Beltran Nicoletta Christodoulou Aravella Zachariou Petra Lindemann-Matthies Susan Barker Costas Kadis 《Environmental Education Research》2017,23(7):1015-1031
This research is based on the rationale that the well-defined framework of education for sustainable development (ESD), its connection with real life and its specific integration in the educational policies and curricula can help to enhance quality education (QE) in a meaningful and identifiable way. In a first step, the common ground of ESD and QE was explored in different areas: common dimensions, future-oriented objectives, commonly targeted skills, value orientation, teaching and learning approaches. In a second step, this information was taken as a base to investigate how well twelve lesson units for primary school reflect the common ground of ESD and QE. The units were specifically developed for this research, in which ESD experienced teachers (mentors) supported inexperienced ones (mentees). Results indicate that ESD can reinforce QE, but that teachers need support with regard to the political and cultural dimensions of SD issues, collaborations with local communities and assessments. 相似文献
69.
This paper studies the patterns of innovation in the ICT field using patents and patent citations. It provides an original methodology to identify ICT applications using patent abstracts and selecting the most frequent sequential triples of words without any a priori selection of keywords. This paper shows that the set of IPC classes related to ICT is broader than the one usually considered.Moreover, our results show that ICT applications can be distinguished into two main groups in terms of growth and structure of innovative activities, technological pervasiveness, and knowledge sources. High opportunity ICT applications are characterised by high growth of patenting activity, high rate of entry of new innovators and high concentration of technological activity across firms. They also display a diversified knowledge base in terms of technological domains and actors involved. Conversely, low opportunity ICT applications are characterised by a lower growth and by a lower concentration of innovative activities across firms, as well as by a lower rate of entry of new innovators. Innovations in these ICT applications show less diversified knowledge sources and a higher degree of internal knowledge base. 相似文献
70.
Bruno Poucet Nicole Chapuis Madeleine Durup Catherine Thinus-Blanc 《Learning & behavior》1986,14(1):93-100
This experiment investigated the role of exploration in the formation of maps of the environment. The effects of spatial rearrangement of four familiar objects in an open field on subsequent exploratory behavior were studied in hamsters (Mesocricetus auratus). During two exploratory sessions, four groups of subjects were exposed to objects in a particular spatial relation to each other and to a distal pattern. During a testing session, the control group was exposed to the same situation as during the first two sessions, and the three experimental groups were exposed to various object rearrangements. The hamsters in the experimental groups, but not those in the control group, renewed their exploration of the objects during the testing session, as measured by the number of contacts with the objects and the time spent investigating them. Further analyses of the nature of the reinvestigated objects (i.e., displaced or nondisplaced) support the hypothesis that, through exploration, a long-lasting representation of the environment is built up on the basis of the topological relations among the objects, the overall geometric structure provided by the arrangement of the objects, and the relations between the objects and extra-apparatus landmarks. 相似文献