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71.
Grade retention and inequalities that derive from grade retention can influence student school trajectories and careers. Grade retention can discourage students from education, and increase school failure and dropout. This study explored the relationship between grade retention and student intentions to enrol in higher education. We also studied the role of school identification and behavioural engagement in this relationship. The analysis is based on a sample of 1,089 students (grades 6 to 10) from Portugal, one of the European countries with the highest rates of grade retention. We employed multilevel probit regression modelling with random intercept and fixed slopes to explore both the individual and school level effects of grade retention. The analyses showed that retained students had a lower probability of intent to enrol in higher education and that there was a contextual effect of the number of retained students in the school, on students' probability of intent to enrol in higher education. This association was partially explained at the individual level by students' school identification. Retained students presented lower levels of school identification, which in turn results in lower probabilities of enrolling in higher education. Student behavioural engagement was not associated with grade retention nor student intentions. Our findings suggest the need for interventions that foster students' school identification to overcome the adverse effects of grade retention.  相似文献   
72.
Knowledge Management Research & Practice - Information and knowledge have been cited over the last two decades as competitive advantage tools. Recently, the use of them has been discussed to...  相似文献   
73.
This study aimed to investigate the fatigue effects induced by a futsal-specific protocol (FIRP) on sprint performance and the kinematics of the lower limbs. Twenty-one futsal players participated in this study and performed a protocol to simulate the futsal demands. At pre-protocol, half-time and post-protocol, the athletes performed 10-m sprints that were recorded for kinematic analysis. Continuous relative phase (CRP) was calculated to assess the inter-segmental coordination. In addition, vertical (KVERT) and leg (KLEG) stiffness were calculated. Analysis of variance (ANOVA) for repeated measures was used (P < 0.05). The main results showed that sprint time increased (P < 0.01) post-protocol when compared to pre- and half-time conditions. Lower values of the step rate (P = 0.01) and higher values of the leg angular velocity (P = 0.02) were verified at the end of the FIRP. The CRP of thigh–leg and leg–foot and the stiffness did not change over the protocol. In addition, the high correlation of CRP between the conditions revealed no changes in coordination pattern. We concluded that futsal related-fatigue induced a decrement on sprint time, changing the kinematics of the lower limbs (decreasing step rate and increasing leg angular velocity). However, neither stiffness nor intersegment coordination during sprints was affected by fatigue.  相似文献   
74.
In outdoor activities, it seems reasonable that the longer children spend in spontaneous physical activity (PA), the higher the probability of being active. Indeed, the time spent outdoor has been identified as a variable consistently associated with the children’s PA. Outdoor playing, such as the organized sports practice, appears associated with healthier lifestyle standards. All the recommendations mention the importance of increasing daily PA practice in children and teenagers, but few studies highlight the relationship between outdoor play and the recommended PA levels. The purpose of this study is to investigate the relationships between the frequency of outdoor play, the frequency of the organized sports practice, and the compliance of the recommendations for PA practice in children in the inner city area of Porto. The sample of this study is composed of 422 individuals (mean age of 11.6 years). Two hundred and twenty-five of them were girls and 197 were boys from the sixth grade (elementary schools located in the inner city area of Porto). PA was objectively evaluated using accelerometers. Participants reported frequency of participation in different PA contexts, such as sports practice and outdoor play. The results show a predictor effect of participating in sports three or more times per week on compliance of PA guidelines.

In conclusion, organized sports practice seems more effective than outdoor play to reach the recommended levels of PA in children.  相似文献   
75.
The aim of the present study was to compare the peak anterior–posterior (Fy) and medio–lateral (Fx) ground reaction forces (GRFs) of women performing stationary running at different intensities in aquatic and dry land environments. Fourteen young women performed the stationary running exercise at three cadences (first ventilatory threshold, second ventilatory threshold and maximum effort, as determined during exercise in water) in aquatic and dry land environments. Two-way repeated measures ANOVA was used to analyse the data (α?=?.05). As a result, significantly lower peak Fy anterior, Fy posterior, Fx medial and Fx lateral values were observed for the aquatic environment, except for the Fy posterior at the first ventilatory threshold. Significant differences were observed between cadences in the peak Fy anterior, Fy posterior, Fx medial and Fx lateral values, with higher values for the cadence corresponding to maximum effort compared to the first ventilatory threshold, except for the Fy posterior and Fx medial in the aquatic environment. The results indicate that the horizontal GRFs are reduced in the aquatic environment and depend on the intensity of stationary running exercise performance.  相似文献   
76.
Coastal tidal wetlands produce and accumulate significant amounts of organic carbon (C) that help to mitigate climate change. However, previous data limitations have prevented a robust evaluation of the global rates and mechanisms driving C accumulation. Here, we go beyond recent soil C stock estimates to reveal global tidal wetland C accumulation and predict changes under relative sea level rise, temperature and precipitation. We use data from literature study sites and our new observations spanning wide latitudinal gradients and 20 countries. Globally, tidal wetlands accumulate 53.65 (95%CI: 48.52–59.01) Tg C yr−1, which is ∼30% of the organic C buried on the ocean floor. Modeling based on current climatic drivers and under projected emissions scenarios revealed a net increase in the global C accumulation by 2100. This rapid increase is driven by sea level rise in tidal marshes, and higher temperature and precipitation in mangroves. Countries with large areas of coastal wetlands, like Indonesia and Mexico, are more susceptible to tidal wetland C losses under climate change, while regions such as Australia, Brazil, the USA and China will experience a significant C accumulation increase under all projected scenarios.  相似文献   
77.
Australian, Iranian and Portuguese university students (n?=?967) completed the University Students Depression Inventory (USDI) in English, Persian and Portuguese languages, respectively. A series of MANOVA analyses were used to examine differences in depression symptoms as an effect of the country and demographic variables. Interactions were also examined. The results indicated that country, gender and year level had some impact on the depressive symptoms of the university students. Australian students were more depressed than the Iranian and Portuguese students, while Iranian students were more depressed than the Portuguese students. Sub-scales of USDI – Lethargy, Motivation and Cognitive/Emotional – were also used to compare the depressive symptoms of students. The Australian female students reported a significantly higher level of lethargy than their male counterparts. Similarly, the first-year male students from Iran were significantly more lethargic than the first-year Iranian female students. Iranian and Portuguese male students, compared to the female students of these countries, experienced a lower level of motivation. The Australian and Iranian students, compared to the Portuguese students, reported a significantly higher level of cognitive and affective symptoms. The scores on the Cognitive/Emotional sub-scale increased with the year level. Differences among students' depression are described and implications discussed.  相似文献   
78.
79.
The work presented is part of a study that the research group CIFO (Research Team in Training for the Labour Market, Autonomous University of Barcelona, Barcelona) has carried out, relating to the training needs analysis and basic competences and skills in the environment of sheltered employment centres (SECs) in Catalonia (this study was undertaken in collaboration with the Coordination of Workshops for People with Mental Disabilities in Catalonia). The analysis and assessment of needs is useful from the perspective of training, as a starting point for planning adapted to the reality of disabled workers in SECs. To do this, various elements such as skills, knowledge and attitudes of individual and social nature have been considered from a systemic approach. By placing ourselves in clearly defined contexts (SECs), we bear in mind the characteristics of workers, the features of the job context, the types of activities performed, the skills related to work activities carried out, the definition of competence profiles required on the basis of the essential skills and the real training needs, through the characteristics of workers and those skills related to the labour activities that are performed as well as the needs for training perceived by workers. Identifying training needs in relation to basic skills and job requirements allows us to meet the challenge, as a trend that supports a competence basis for any worker, of raising general actions that may govern and underlie the training proposals, yet without undermining the specific competences. The importance acquired by what workers themselves have considered about their positioning is understood from the standpoint of its validity, so as to assume conclusions through triangulation processes.  相似文献   
80.
Nuno Gil 《Research Policy》2007,36(7):980-999
This study defines a project safeguard as the design and physical development work needed to ensure, or enhance, the embedding of a real option in complex products and systems (CoPS). Safeguards operationalize optionlike strategic thinking at implementation. I examine safeguarding investments through an in-depth multiple-case study of 12 options embedded across 5 projects encompassed by an airport expansion programme. This includes options to phase out delivery (stage-option), grow capacity (growth-option), and switch operational regime (switch-option). Passive safeguards only involve design work, whereas active safeguards involve both design and physical execution. The analysis shows how the confluence between the uncertainty of option exercising and the modularity of the relevant functional elements in relation to the CoPS architecture affects the attractiveness of safeguarding. High uncertainty makes safeguarding less attractive as it can lead to sunk costs that may not pay off over the CoPS operating life. Conversely, high modularity increases the attractiveness of safeguarding because (1) safeguards can be limited to marginal investments at the interfaces between the functional elements with other CoPS subsystems, and (2) the stability of modular design rules increases the likelihood that safeguards remain valid over time. Safeguards build options into integrative CoPS. This flexibility and redundancy makes them resilient to change stemming from option exercising if uncertainties resolve favourably in the future.  相似文献   
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