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1.
Little is known regarding the profiles of whole body donors in Muslim majority countries where donation is scarce. Therefore, this study aims to profile registered donors in Turkey by means of a survey. The explored data could be used to improve ongoing campaign efforts and ethical practices such as commemoration services. Registered donors of the donation programs at the two faculties of medicine of Istanbul University were compared with the national population and a cluster analysis was performed to reveal any concealed sub-groups. Data from 188 respondents were analyzed. The majority of registered donors were married (42%), male (65.4%), aged over 50 years (76%), held a tertiary education degree (49.7%), and were irreligious (58.5%). Cluster analysis revealed two groups with significantly different educational levels, marital statuses, and religious choices. Regarding whether their bodies could be used for education or research, the majority (64.5%) of the respondents left the decision to the anatomy department. Similarly, 73.8% approved indefinite use of their organs, body parts and/or skeletons. The respondents were also willing to share their medical history (94.2%) and personal information (81.6%) if needed. Motivational themes for body donation including usefulness, impermanence, religion, awareness, and kinship were devised after a thematic analysis. Among the respondents, 56.5% were registered organ donors and 63.3% were frequent blood donors. The results of this study provide data that may help revising informed consent forms, developing and implementing thanksgiving ceremonies, and selecting additional targets for supporting body donation campaign activities such as organ and blood donation units.  相似文献   
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Serious games are becoming increasingly popular due to their association with increased learning outcomes when compared to traditional self-regulated learning activities. However, the majority of research examining the outcomes of serious games has focused almost exclusively on learning outcomes. This has resulted in a lack of research examining why these types of games result in increased positive outcomes, such as engagement or performance. This study seeks to address this gap in existing research by examining the relationship between game difficulty and participants’ engagement, performance and self-efficacy in a Pacman style maze navigation game. This required the use of hidden difficulty variations which participants were randomly assigned. Participants engaged with the game over a 5-days practice period. Results from this study suggest that difficulty plays a considerable role in influencing participants’ self-efficacy for the task. Self-efficacy has been consistently linked to positive outcomes such as increased engagement and performance. This highlights the importance of difficulty as a game design factor as well as providing an insight into the manner in which serious games could be further refined in order to increase user’s self-efficacy and associated positive outcomes. Implications for future serious games and self-efficacy research are discussed.  相似文献   
3.
Weighted vests are widely used to improve running economy and performance. However, it is not well-studied how running mechanics are adapted to counteract the higher peak vertical ground reaction forces (Fpeak) while running with such a device. Therefore, the present study aimed to investigate the effects of different loading conditions on running mechanics at different velocities. Thirteen subjects participated in two separate sessions one week apart. In the first session, maximal aerobic speed (MAS) was determined through a maximal incremental running test while in the second session, they were instructed to run during one minute under different loading (0%, +10% and +20% of body mass [BM]) and velocity (60%, 80% and 100% of MAS) conditions in a random order. Spatiotemporal data were recorded and then running mechanics modelled using the spring-mass model. The main results indicated that vertical and leg stiffness (Kvert and Kleg, respectively) were increased (P?P?>?.05) when load was changed. At the same time, alterations of the running kinematics were observed such as longer contact times, reduced flight times, stride frequencies and step lengths, as well as an increase of the centre of mass dynamics. Based on these results it is assumed that runners maintain a certain stiffness level for each velocity despite different loading conditions. As a consequence, Fpeak increases and this probably causes spatiotemporal adjustments in the movement kinematics.  相似文献   
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ABSTRACT

The present study aimed to provide reference values for lower-limb muscle power assessed during the incremental jump squat (JS) test in elite athletes (i.e., professional athletes competing at international level). We pooled data from all JS tests performed by elite athletes of different sports in two high-performance centres between 2015 and 2019, and computed reference values (i.e., terciles) for mean power (MP), mean propulsive power (MPP), and peak power (PP). Reference values were obtained from 684 elite athletes (458 male and 226 female) of 16 different sports (boxing, judo, karate, fencing, taekwondo, wrestling, basketball, soccer, futsal, handball, rugby union, badminton, tennis, long distance running, triathlon, and sprinting). Significant differences (p < 0.001) were found between male and female athletes for MP (7.47 ± 1.93 and 6.15 ± 1.68 W·Kg?1, respectively), MPP (10.50 ± 2.75 and 8.63 ± 2.43 W·Kg?1), and PP (23.64 ± 6.12 and 19.35 ± 5.49 W·Kg?1). However, the velocity at which these power measures was attained seemed to be independent of sex (~0.95, 1.00 and 2.00 m·s?1 for mean, mean propulsive, and peak velocity, respectively) and homogeneous across different sport disciplines (coefficient of variation <10%). These data can be used to classify athletes’ power capabilities, and the optimum velocity ranges provided here could be useful for training purposes.  相似文献   
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ABSTRACT

One of the most memorable moments in the World Cups history is Marco Tardelli’s second goal in Italy’s win over Germany in the 1982 World Cup finals. Better known as Tardelli’s scream, it is thus a perfect object to analyse in order to understand football’s deeper social meanings and its political and cultural undertones, in this case both for the World Cup champions, Italy, and for the host country, Spain. In the Spanish case, organizing the World Cup was a huge political opportunity for the just restored democracy to showcase to the world a modern and pluralistic society leaving behind the authoritarian and outdated dictatorship. As for Italy, their first World Cup winning since World War II was heavily politically used by actors across the political spectrum. Such nationalistic approach constituted a novelty after decades of a low profile national discourse.  相似文献   
7.
The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   
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European Journal of Psychology of Education - Children’s motivation to master challenging tasks is an important predictor of school success, and yet, such motivation declines during...  相似文献   
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ABSTRACT

Background: Schoolchildren’s personality development is considered a central goal of physical education (PE). With regard to the relationship between psychological well-being and global self-esteem over the life course, the promotion of positive self-esteem is an issue of particular significance. Past research revealed that PE taught with an individualized teacher frame of reference (iTFR) and a reflexive teaching style is associated with positive effects on facets of children’s perceived sports competence. However, it remains an open question whether this teaching styles has the potential to promote positive self-esteem.

Purpose: The present study investigated whether a five-month teacher training, aimed to enhance the teachers’ iTFR and their reflexive teaching style in PE, has a positive effect on students’ perceived sports competence and their global self-esteem. To analyse the implementation quality, changes in students’ perceived iTFR and perceived reflexive teaching style were investigated.

Method: A total of 21 teachers were assigned to either an intervention group (n?=?13), receiving the five-month teacher training, or a control group (n?=?8) consisting of regular teaching without teacher training. The teacher training encompassed five three-hour consecutive sessions during which the teachers acquired theoretical and practical knowledge about the promotion of competence perceptions in PE with a reflexive teaching style and an iTFR. Between the sessions, the teachers were instructed to implement an iTFR and a reflexive teaching style into their own PE classes. To evaluate the effects of the teacher training, their students’ (N?=?315, 53.7% girls, Mage?=?13.2 y, SDage?=?1.3 y) perceived teaching style (iTFR and reflexive teaching), perceived sports competence and global self-esteem were measured with paper-pencil questionnaires at three measurement points (pre, post and follow-up).

Findings: Linear mixed effect models showed that students of the intervention group reported an increase in their teachers’ reflexive teaching style, but there were no changes with regard to iTFR. With regard to students’ perceived sports competence and global self-esteem, there were significant interaction effects between time and group over a period of eight months (from pre-test to follow-up), indicating positive effects on these self-concept dimensions due to the teacher training.

Conclusion: The present study indicates that a long-term teacher training supports PE teachers to implement teaching styles with the aim to promote students’ self-concept. Furthermore, the findings lead to the assumption that a more pronounced iTFR in combination with an enhanced reflexive teaching style has the potential to positively influence schoolchildren’s perceived sports competence and global self-esteem.  相似文献   
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