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991.
The Internet has become one of the most common instructional tools because of recent developments in telecommunications and Internet technology. Accordingly, educators increasingly support the use of the Internet in the social studies classroom. Thus, the purpose of this study was to investigate pre‐service elementary teachers’ beliefs about the use of the Internet in the social studies classroom. Data were collected through an open‐ended questionnaire from 37 pre‐service elementary teachers in a large Turkish university. An inductive analysis approach was used to analyse the data. Thus, the emergent patterns of the data were used to develop coding categories. The data analysis indicated that the majority of the participants supported the use of the Internet in the social studies classroom, while they acknowledged the disadvantages and negative aspects of the use of the Internet.  相似文献   
992.
Taking as reference the proposals of the European Higher Education Area, the aim of this study is to identify the competencies which a wide sample of teachers in Spanish primary schools (6–12 age group) consider to be important for their professional performance and which they use in their everyday teaching, and to what extent their university training prepared them for their practising professional development. To do this, an ad hoc instrument was devised and applied to experienced practising teachers and to teacher trainees who were on teacher training placements during the last semester of their course. The results of the study show that initial teacher training should deal in depth with the competencies related to the organisation and management of teaching–learning, the use of new technologies in the primary classroom, the involvement of the families, education in values, social skills and skills for working in professional groups. Finally, proposals are made for training based on the articulation between theory and practice, to allow the professional competencies mentioned to be developed and used in practice, as well as encouraging close collaboration between teacher trainers and experienced practising teachers.  相似文献   
993.
This paper addresses the problem of encircling and tracking a moving target with a fleet of unicycle-like vehicles. A new control law is developed to steer the vehicles to an evenly spaced formation along a circumference, the center of which tracks the motion of the target. The strategy proposed relies only on the relative positions of the agents with respect to the target, expressed in the local frame of each vehicle. The absolute position, velocity and acceleration of the target are unknown. Additionally, the robustness of the proposed control law in the presence of external disturbances is analyzed. Communication among agents is used to maintain the vehicles equally spaced in the circular formation. Simulation results illustrate the effectiveness of the proposed strategies.  相似文献   
994.
正Osteoarthritis(OA)is a degenerative joint disease,typified by a loss of quality of cartilage and changes in bone at the interface of a joint,resulting in pain,stiffness,and reduced mobility."According to the World Health Organization,40%of people over the age of 70 have OA.This joint disease affects  相似文献   
995.
This paper studies the global asymptotic stability of a class of interval fractional-order (FO) nonlinear systems with time-delay. First, a new lemma for the Caputo fractional derivative is presented. It extends the FO Lyapunov direct method allowing the stability analysis and synthesis of FO nonlinear systems with time-delay. Second, by employing FO Razumikhin theorem, a new delay-independent stability criterion, in the form of linear matrix inequality is established for ensuring that a system is globally asymptotically stable. It is shown that the new criterion is simple, easy to use and valid for the FO or integer-order interval neural networks with time-delay. Finally, the feasibility and effectiveness of the proposed scheme are tested with a numerical example.  相似文献   
996.
Background: School is one of the primary settings where non-gender conformer children and adolescents emerge as vulnerable groups at high risk of suffering violence and harassment. Within schooling contexts, embodied experiences in physical education (PE) may become particularly problematic for trans students. However, there is little research focusing on trans persons’s experiences in PE. The purpose of this paper is to gather memories and impressions of a group of adult trans persons on their experiences in secondary PE.

Theoretical framework: The concept of heteronormativity is used as a theoretical framework to provide insights and understanding to trans persons’s experiences in PE. It is used to characterize inequalities and hierarchies derived from the intersection of the dualistic logic of gender binarism with other social categories and ideologies. Heteronormative discourses also act regulating the way of looking at and over trans persons’ bodies, categorizing some of them as queer or abject.

Participants and methodology: Study is based on semi-structured interviews to nine participants (five trans women and four trans men) from 23 to 62 years of age. A thematic analysis was carried out in order to flexibly and directly identify interpretative patterns of meaning within data, as well as to open them to interpretative frameworks. The categories were grouped into four themes best gathering the experiences of participants in PE.

Results and discussion: (1) Hindering desired gender: In daily practices, participants felt in ‘the middle’ of activities, spaces and gender groups, experiencing aloofness, isolation and loneliness. Participants complained about the fact that they could not perform gender segregated activities with their desired gender group. PE teachers played an important role in supporting heteronormative system. (2) Preferences, aversions and opportunities: All participants experienced hegemonic forms of gender and sexuality linked to PE programme activities in different ways. For most trans boys, sport-based PE was their favourite subject, while trans girls found it particularly negative and demotivating. Exceptionally, some aesthetic and dance activities were recalled as nearly non-heterosexual practices. (3) Confronting transgression. Situations of stigmatization and bullying in PE were frequent as a result from situations in which gender norms were eventually transgressed. Teachers impeded any attempt of trans persons to overcome heteronormativity in PE lessons. (4) Intimacy struggles: Body intimacy was crucial for participants. Different strategies were used for the search of intimacy. Changing rooms were the most problematic spaces for trans students in educative contexts. The worse trans participants felt about their bodies, the more uneasy they felt in these facilities.

Conclusions and final comments: Heteronormative contexts strongly determined trans persons’ experiences in PE. Trans participants, especially those not performing gender conforming practices, were abjectified in PE lessons. This situation generated multiple forms of exclusion and rejection, as well as episodes of harassment. However, some practices counteracted the dominance of the heteronormative system, showing their potential to destabilize this ideology in PE.  相似文献   

997.
Even though injury is common in elite sports, there is still a lack of knowledge of young athletes’ injury perception both during and after injury. The aim of this mixed-method study was, therefore, to explore, in-depth, data on injury consequences and adolescent elite athletes’ perceptions and experience of injury. Three hundred and forty adolescent elite athletes (age range 15–19), from 16 different sports, were bi-weekly monitored over 52 weeks using a valid questionnaire. Twenty athletes from the same cohort were interviewed in focus groups about injury experience and perceptions. The results show that the average bi-weekly prevalence of injury was 38.7% (95% CI 37.3–40.1), with 30.0% (n?=?102) of the athletes injured for more than half of all reporting times. An overarching theme from the focus groups highlighted the risk among young athletes of a loss of identity while injured. The findings support several suggestions that may improve the rehabilitation process and enhance rehabilitation outcomes: (a) provide clear pathways to the medical team, (b) recognize the identity loss, (c) involve the injured athletes with the rest of the teammates and (d) educate athletes about how to interpret pain signals. Future research should explore and evaluate the effectiveness and generalization of such interventions.  相似文献   
998.
This study aimed to determine the effect of different percentages of body weight support (BWS) on spatiotemporal step characteristics during running. 26 endurance runners (age: 37 ± 9 years) completed a running treadmill protocol consisting of 6 different conditions (BWS combinations: 0–50%), with velocity maintained at 12 km/h. Each condition lasted 1 minute. Step angle, ground contact time (CT), flight time (FT), step length (SL) and frequency (SF), and duration of phases during stance time (phase1: initial contact; phase2: midstance; phase3: propulsion) were measured for every step during the test using a photoelectric cell system. Compared with the baseline condition (100% BW), FT was longer, CT was shorter, SL was longer, SF was lower, and the step angle was higher with each increase in BWS (p < 0.05). Also, some changes were observed in the duration of phases during stance time: phase1 did not experience changes across experimental conditions (p = 0.096), phase2 decreased and phase3 increased as BW was supported (p < 0.05). These results indicate that as BW was supported, runners showed longer FT and SL, shorter CT, lower SF, and greater step angle as well as some changes in the phases during the ground contact. Therefore, this study highlights the effect of different percentages of BWS on spatiotemporal parameters.  相似文献   
999.
The aim was to compare the passive drag-gliding underwater by a numerical simulation and an analytical procedure. An Olympic swimmer was scanned by computer tomography and modelled gliding at a 0.75-m depth in the streamlined position. Steady-state computer fluid dynamics (CFD) analyses were performed on Fluent. A set of analytical procedures was selected concurrently. Friction drag (Df), pressure drag (Dpr), total passive drag force (Df+pr) and drag coefficient (CD) were computed between 1.3 and 2.5 m · s?1 by both techniques. Df+pr ranged from 45.44 to 144.06 N with CFD, from 46.03 to 167.06 N with the analytical procedure (differences: from 1.28% to 13.77%). CD ranged between 0.698 and 0.622 by CFD, 0.657 and 0.644 by analytical procedures (differences: 0.40–6.30%). Linear regression models showed a very high association for Df+pr plotted in absolute values (R2 = 0.98) and after log–log transformation (R2 = 0.99). The CD also obtained a very high adjustment for both absolute (R2 = 0.97) and log–log plots (R2 = 0.97). The bias for the Df+pr was 8.37 N and 0.076 N after logarithmic transformation. Df represented between 15.97% and 18.82% of the Df+pr by the CFD, 14.66% and 16.21% by the analytical procedures. Therefore, despite the bias, analytical procedures offer a feasible way of gathering insight on one’s hydrodynamics characteristics.  相似文献   
1000.
This study investigated the effects of fatigue on balance control and cognitive performance in a standing shooting position. Nineteen soldiers were asked to stand while holding a rifle (single task – ST). They also had to perform this postural task while simultaneously completing a cognitive task (dual task – DT). Both the ST and DT were performed in pre- and post-fatigue conditions. In pre-fatigue, participants achieved better balance control in the DT than in the ST, thus suggesting that the increased cognitive activity associated with the DT improves balance control by shifting the attentional focus away from a highly automatised activity. In post-fatigue, balance control was degraded in both the ST and DT, while reaction time was enhanced in the first minutes following the fatiguing exercise without affecting the accuracy of response in the cognitive task, which highlights the relative independent effects of fatigue on balance control and cognitive performance.  相似文献   
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