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1.
Tennis coaches often use the fundamental throwing skill as a training tool to develop the service action. However, recent skill acquisition literature questions the efficacy of non-specific training drills for developing complex sporting movements. Thus, this study examined the mechanical analogy of the throw and the tennis serve at three different levels of development. A 500 Hz, 22-camera VICON MX motion capture system recorded 28 elite female tennis players (prepubescent (n = 10), pubescent (n = 10), adult (n = 8)) as they performed flat serves and overhand throws. Two-way ANOVAs with repeated measures and partial correlations (controlling for group) assessed the strength and nature of the mechanical associations between the tasks. Preparatory mechanics were similar between the two tasks, while during propulsion, peak trunk twist and elbow extension velocities were significantly higher in the throw, yet the peak shoulder internal rotation and wrist flexion angular velocities were significantly greater in the serve. Furthermore, all of these peak angular velocities occurred significantly earlier in the serve. Ultimately, although the throw may help to prime transverse trunk kinematics in the serve, mechanics in the two skills appear less similar than many coaches seem to believe. Practitioners should, therefore, be aware that the throw appears less useful for priming the specific arm kinematics and temporal phasing that typifies the tennis serve.  相似文献   

2.
Background and purpose: Attentional focus cues have been shown to impact motor performance of adults and children. Specifically, an external focus of attention results in improved motor learning and performance as compared to adopting an internal focus of attention. The purpose of this study was to determine the effects of an internal and external attentional focus cue on children’s object control skill performance during a commonly used motor skill assessment.

Methods: Using a within-participant design, a total of 44 children (Mage?=?7.7 years, 20 boys and 24 girls) completed all three attentional focus conditions. The object control subscale of the Test of Gross Motor Development-2nd Edition (TGMD-2; Ulrich, 2000. Test of Gross Motor Development-2. Austin: Pro-Ed.) served as the motor skill assessment in present study. The TGMD-2 is a normed and criteria-referenced assessment frequently used to assess fundamental motor skill competence in children. The object control subtest of the TGMD-2 assesses a child’s ability to complete six fundamental motor skills – striking a stationary ball, stationary dribble, catch, kick, overhand throw, and underhand roll. All participants completed the object control subtest of the TGMD-2 under three different attentional focus conditions: baseline (i.e. neutral focus), internal, and external. The internal cue focused on movement performance and the external cue focused on movement outcome. In all three conditions, a video demonstration of proper skill performance was used to ensure no difference in visual demonstration, but the overlaying audio was changed to encompass each attentional focus condition. Children’s motor performance was recorded and later coded by a single researcher blinded to the study. A repeated-measures analysis of variance was used to determine if children’s motor scores changed among the three conditions.

Results: Findings demonstrated that children’s performance differed among the three conditions (F(2,43)?=?3.5, p?Post hoc analysis revealed that children scored significantly better in the external cue condition compared to the baseline (difference?=?1.98, p?Conclusion: Children performed better when given a verbal instruction to focus their attention externally rather than a verbal instruction with no attentional focus cue. No significant differences exist between the internal and external focus condition or between the neutral and internal condition. Our findings align with the literature and support that external attentional focus cues have a positive effect on motor performance. From a teaching and learning standpoint, using consistent instructions appears to be essential for young learners. Slight changes in verbal cues can have a significant effect on how well children execute fundamental motor skills.  相似文献   

3.
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4.
This study was designed to investigate the effect of an interactive videodisc motor skill assessment training program on the development of preservice and inservice teachers' qualitative assessment proficiency on two motor skills: the overhand throw and catch. Twenty-seven preservice and 27 inservice physical education teachers were randomly assigned to one of three treatment conditions: interactive videodisc (IVD), teacher-directed (TD), or self-directed (SD). Motor skill qualitative assessment accuracy was evaluated on a pre- and post-test basis using a 50-item motor skill assessment accuracy test (10 performances rated on 5 components) for each skill. Analysis of covariance results indicated significant main effects for treatment for both skills. Post hoc tests revealed that for the overhand throw, the IVD and TD groups were superior to the SD group but not different from each other. For the catch, the IVD group was found to be superior to both the TD and SD groups. These findings are discussed in relation to the advantages of interactive videodisc in terms of efficiency and user independence and with comparable findings in other educational applications.  相似文献   

5.
Abstract

This study was designed to investigate the effect of an interactive videodisc motor skill assessment training program on the development of preservice and inservice teachers' qualitative assessment proficiency on two motor skills: the overhand throw and catch. Twenty-seven preservice and 27 inservice physical education teachers were randomly assigned to one of three treatment conditions: interactive videodisc (IVD), teacher-directed (TD), or self-directed (SD). Motor skill qualitative assessment accuracy was evaluated on a pre- and post-test basis using a 50-item motor skill assessment accuracy test (10 performances rated on 5 components) for each skill. Analysis of covariance results indicated significant main effects for treatment for both skills. Post hoc tests revealed that for the over hand throw, the IVD and TD groups were superior to the SD group but not different from each other. For the catch, the IVD group was found to be superior to both the TD and SD groups. These findings are discussed in relation to the advantages of interactive videodisc in terms of efficiency and user independence and with comparable findings in other educational applications.  相似文献   

6.
Purpose: This feasibility study compared the effects of 2 movement programs, traditional and mastery climate (i.e., the Children’s Health Activity Motor Program [CHAMP]), on lesson context and children’s physical activity (PA) levels. A secondary aim was to examine sex differences in PA levels in both programs. Method: Seventy-two preschoolers served as participants and were assigned to a movement program. Physical activity levels and lesson context were assessed with the System for Observing Fitness Instruction Time. Results: Preschoolers in CHAMP spent more time walking (p < .05, d = 3.3), more time in moderate-to-vigorous PA (MVPA; p < .05, d = 3.6), and less time standing (p < .05, d = 3.8) compared with those in a traditional movement program. Boys in both programs spent less time standing (p < .05, d = 4.8) and more time in vigorous activity (p < .05, d = 5.8) and MVPA (p < .05, d = 4.4) compared with girls. During CHAMP, children spent less time engaged in management and knowledge (p < .05, d = 1.4, and p < .001, d = 0.9, respectively) and more time in skill practice (p < .05, d = 1.5). Conclusion: The findings support that participation in CHAMP elicits more MVPA in preschool-age children compared with a traditional movement program. The Children’s Health Activity Motor Program provided children with more class time devoted to skill practice. The program appears to be an innovative approach that is beneficial for PA engagement and could contribute positively to children’s health.  相似文献   

7.
We assessed the effects on basketball free throw performance of two types of verbal directions with an external attentional focus. Novices ( n = 16) were pre-tested on free throw performance and assigned to two groups of similar ability ( n = 8 in each). Both groups received verbal instructions with an external focus on either movement dynamics (movement form) or movement effects (e.g. ball trajectory relative to basket). The participants also observed a skilled model performing the task on either a small or large screen monitor, to ascertain the effects of visual presentation mode on task performance. After observation of six videotaped trials, all participants were given a post-test. Visual search patterns were monitored during observation and cross-referenced with performance on the pre- and post-test. Group effects were noted for verbal instructions and image size on visual search strategies and free throw performance. The 'movement effects' group saw a significant improvement in outcome scores between the pre-test and post-test. These results supported evidence that this group spent more viewing time on information outside the body than the 'movement dynamics' group. Image size affected both groups equally with more fixations of shorter duration when viewing the small screen. The results support the benefits of instructions when observing a model with an external focus on movement effects, not dynamics.  相似文献   

8.
The aim of this study was to compare the effects of physical practice with PETTLEP-based (Physical, Environment, Task, Timing, Learning, Emotion and Perspective; Holmes & Collins, 2001) imagery and PETTLEP + physical practice interventions on golf bunker shot performance. Thirty-two male county- or international-level golfers were assigned to one of four groups; PETTLEP imagery, physical practice, PETTLEP + physical practice, or control. The PETTLEP imagery group imaged 15 bunker shots, their interventions incorporating PETTLEP components, such as physical, environment, and emotion, twice a week. The physical practice group physically performed their 15 bunker shots twice per week; the PETTLEP + physical practice group performed PETTLEP imagery once per week and physical practice once per week. Each group performed their respective tasks for 6 weeks. Pre- and posttests consisted of 15 bunker shots, with points awarded according to the ball proximity to the pin. All groups improved significantly (p < .01) from pre- to posttest, and the PETTLEP + physical practice group improved more (p < .05) than the PETTLEP and physical practice groups. However, there was no significant difference between the physical practice and PETTLEP groups (p > .05). Findings, therefore, support the effectiveness of PETTLEP in enhancing golf performance, especially when combined with physical practice.  相似文献   

9.
The aim of this study was to compare the effects of physical practice with PETTLEP-based (Physical, Environment, Task, Timing, Learning, Emotion and Perspective; Holmes &; Collins, 2001) imagery and PETTLEP + physical practice interventions on golf bunker shot performance. Thirty-two male county- or international-level golfers were assigned to one of four groups; PETTLEP imagery, physical practice, PETTLEP + physical practice, or control. The PETTLEP imagery group imaged 15 bunker shots, their interventions incorporating PETTLEP components, such as physical, environment, and emotion, twice a week. The physical practice group physically performed their 15 bunker shots twice per week; the PETTLEP + physical practice group performed PETTLEP imagery once per week and physical practice once per week. Each group performed their respective tasks for 6 weeks. Pre- and posttests consisted of 15 bunker shots, with points awarded according to the ball proximity to the pin. All groups improved significantly (p < .01) from pre- to posttest, and the PETTLEP + physical practice group improved more (p < .05) than the PETTLEP and physical practice groups. However, there was no significant difference between the physical practice and PETTLEP groups (p > .05). Findings, therefore, support the effectiveness of PETTLEP in enhancing golf performance, especially when combined with physical practice.  相似文献   

10.
We assessed the effects on basketball free throw performance of two types of verbal directions with an external attentional focus. Novices (n = 16) were pre-tested on free throw performance and assigned to two groups of similar ability (n = 8 in each). Both groups received verbal instructions with an external focus on either movement dynamics (movement form) or movement effects (e.g. ball trajectory relative to basket). The participants also observed a skilled model performing the task on either a small or large screen monitor, to ascertain the effects of visual presentation mode on task performance. After observation of six videotaped trials, all participants were given a post-test. Visual search patterns were monitored during observation and cross-referenced with performance on the pre- and post-test. Group effects were noted for verbal instructions and image size on visual search strategies and free throw performance. The 'movement effects' group saw a significant improvement in outcome scores between the pre-test and post-test. These results supported evidence that this group spent more viewing time on information outside the body than the 'movement dynamics' group. Image size affected both groups equally with more fixations of shorter duration when viewing the small screen. The results support the benefits of instructions when observing a model with an external focus on movement effects, not dynamics.  相似文献   

11.
Purpose: The purpose of this study was to examine whether functional movement proficiency could be improved as measured via the Functional Movement Screen using a standardized warm-up protocol in middle school physical education. A secondary purpose was to determine whether such improvement, if it occurred, would positively influence the technical performance of 4 fundamental motor skills: overhand throw, vertical jump, kicking, and running. Method: Participants were 120 7th- and 8th-grade physical education student volunteers. Two classes from each grade level were assigned to the functional group (N = 54) while the remaining 2 classes of each grade were assigned to the control group (N = 66). Baseline measures were obtained using the Functional Movement Screen and the Get Skilled: Get Active (2000) process-oriented motor skill assessment. For 6 weeks, the functional group warmed up by performing functional stretching, stability, and mobility exercises while the control group completed a traditional dynamic warm-up. Results: According to gain score analysis, those in the functional group significantly reduced dysfunctional movements (scores of 1) compared with those in the control group. Further, boys in the functional group significantly improved their Functional Movement Screen composite score as compared with their male counterparts in the control group whose scores declined. No differences were found for fundamental motor skill performance. Conclusion: Replacing the traditional dynamic warm-up with one that emphasizes functional movement in preparation for activity in physical education appears effective for correcting movement dysfunctions in young adolescents.  相似文献   

12.
Purpose: The ability to anticipate the actions of opponents can be enhanced through perceptual-skill training, though there is doubt regarding the most effective form of doing so. We sought to evaluate whether perceptual-skill learning would be enhanced when supplemented with guiding visual information. Method: Twenty-eight participants without soccer-playing experience were assigned to a guided perceptual-training group (n = 9), an unguided perceptual-training group (n = 10), or a control group (n = 9). The guided perceptual-training group received half of their trials with color cueing that highlighted either the key kinematic changes in the kicker's action or the known visual search strategy of expert goalkeepers. The unguided perceptual-training group undertook an equal number of trials of practice, but all trials were without guidance. The control group undertook no training intervention. All participants completed an anticipation test immediately before and after the 7-day training intervention, as well as a 24-hr retention test. Results: The guided perceptual-training group significantly improved their response accuracy for anticipating the direction of soccer penalty kicks from preintervention to postintervention, whereas no change in performance was evident at posttest for either the unguided perceptual-training group or the control group. The superior performance of the guided perceptual-training group was preserved in the retention test and was confirmed when relative changes in response time were controlled using a covariate analysis. Conclusions: Perceptual training supplemented with guiding information provides a level of improvement in perceptual anticipatory skill that is not seen without guidance.  相似文献   

13.
Background: Young children from disadvantaged settings often present delays in fundamental motor skills (FMS). Young children can improve their FMS delays through developmentally appropriate motor skill intervention programming. However, it is unclear which pedagogical strategy is most effective for novice and expert instructors.

Purpose: The purpose of this study was to examine the effects of a motor skill intervention delivered by expert and novice teachers via direct or indirect pedagogical strategy on the object control and locomotor skills of young children.

Participants and setting: Participants included children (N?=?109) aged 40–67 months (Mage?=?54 months, SD?=?7 months) enrolled in an early years center for children who are socioeconomically disadvantaged in the United States.

Data collection: Children participated in one of five instructional conditions (expert-led direct, expert-led indirect, novice-led direct, novice-led indirect, and control). Expert and preservice physical education teachers implemented the Successful Kinesthetic Instruction for Preschoolers (SKIP) motor skill program twice weekly for 6 weeks (360?min of instruction). Children in all experimental conditions (n?=?69) received ‘business as usual’ free play on nonintervention days. Children in the control condition (n?=?40) received the ‘business as usual’ free play 5 days weekly throughout the entirety of the intervention. Children completed the Test of Gross Motor Development-2 during the pretest and the posttest.

Data analysis: For object control and locomotor skills, we conducted two, separate, one-way ANOVAs at the pretest to determine condition differences. We then calculated two separate, five conditions × two times repeated-measures ANOVAs to determine the effects of SKIP on both object control and locomotor skills. Tukey post hoc analyses confirmed posttest differences among the conditions.

Findings: There were no significant differences among conditions at the pretest (locomotor, p?=?.347–.969; object control, p?=?.143–.918). For object control skills, there were significant main effects for time (F[1, 104]?=?83.92, p?.001, η2?=?.45) and condition (F[4, 104]?=?6.39, p?<?.001, η2?=?.20) as well as a significant time by condition interaction (F[4, 104]?=?22.36, p?<?.001, η2?=?.45). For locomotor skills, there was a significant main effect for time (F[1, 104]?=?41.25, p?<?.001, η2?=?.28) but not for condition (F[4, 104]?=?2.20 p?<?.074, η2?=?.08). There was a significant time by condition interaction (F[1, 104]?=?18.68, p?<?.001, η2?=?.42). Experts, regardless of strategy, showed significantly greater improvements (p?<?.001) than novice and control conditions for locomotor skills. For object control skills, experts (all conditions) and novice-direct demonstrated significantly (p?<?.001) greater gains than the control and novice-indirect conditions.

Conclusion: Young children from disadvantaged settings demonstrated developmental delays with FMS. Motor skill intervention was effective with remediating their delays. Novice teachers with limited physical education experience should begin teaching object control skills via direct instruction. Experts can choose either direct or indirect instructional strategies. Future research should investigate the implications of scaffolding locomotor skills and indirect pedagogical strategies for novice teachers.  相似文献   

14.
Background: The advent of technology use in physical education is upon us. But the implications of using exergames as a substitute for traditional physical education instruction for some students raise questions. Although exergames have the potential to increase energy expenditure and motivation in some children, it is less clear whether they can provide skill acquisition benefits that are similar to those found in traditional physical education.

Purpose: In a previous experiment from our laboratory, we found that deliberate practice can significantly reduce the planning time required for lateral arm movements. The purpose of this study was to determine if exergames can produce a similar effect, by reducing the processing time required for children to initiate arm movements to the contralateral and ipsilateral space.

Participants and setting: Thirty children (boys?=?15, girls?=?15), between the ages of 7 and 12 years, participated in a pre- and post-test each taking 30?min and one 30?min treatment session in a university laboratory.

Research design: A repeated measures design was employed to test the effects of deliberate laterality practice on processing speed. Children were randomly assigned (n?=?10) to either a Nintendo Wii tennis contralateral movement experimental group, Nintendo Wii bowling ipsilateral movement experimental group, or handheld video-game control group. Each child participated in one 30?min treatment session.

Data collection: Upper extremity choice reaction time (RT) was measured through 27 goal-directed aiming movements for each arm separately, during the pre-test and post-test. The stimulus–response trials occurred in three randomly presented directions (ipsilateral, contralateral, and midline).

Data analysis: A 3 (treatment group)?×?2 (age group)?×?2 (test)?×?3 (direction) mixed design analysis of variance with repeated measures on the last two factors was used to test for significant differences, with an alpha level set at 0.05.

Findings: There were no significant treatment effects on RT across all groups indicating that a short bout of exergame training was unsuccessful in improving lateral movement processing.

Conclusions: Deliberate laterality practice using exergames did not improve the motor processing speed of lateral arm movements in the same manner of traditional physical education as indicated by our previous research. Explanations as to why exergames do not exhibit the same positive transfer for skill acquisition as traditional physical education instruction are discussed within this paper.  相似文献   

15.
Objective: To examine children’s energy expenditure (EE) during object projection skill performance at three intensity intervals. Methods: Children’s (42, Mage = 8.1) average metabolic equivalents of task (METs) were calculated using a COSMED K4b2 while they repeatedly performed blocks of kicking, throwing (overhand), and striking (two-handed) during 6, 12, and 30-s interval conditions. A repeated-measures analysis of covariance examined differences in METs while controlling for skill level. Results: Data indicated a main effect for interval condition (df = 2, 123, F = 94.36, p <.001, η2 = .605). Post hoc t-tests demonstrated decreasing performance interval times yielded progressively higher METs (p <.001) across the three conditions (30s = 4.5±0.8 METs, 12s = 6.3±1.3, 6s = 8.3±1.6). There also was a main effect for sex (df = 1,120, F = 52.28, p <.001 η2 = .305). Boys demonstrated higher METs at each performance interval (p <.001). Conclusion: Skill practice with a maximum of one trial every 30s resulted in the equivalent of at least moderate physical activity (>4.0 METs) and intervals of 6s demonstrated vigorous physical activity (>7.0 METs). Practicing/performing object projection skills, even at intervals that allow for adequate instruction and feedback (i.e., 1 trial/30s), promotes MVPA in children.  相似文献   

16.
Abstract

This study investigated the effects of sex and athletic status on reaction latencies and movement time. One hundred subjects, categorized into five groups of 20 subjects each—male athletes (MA), female athletes (FA), male nonathletes (MNA), female nonathletes (FNA), and control group (CG)—were tested over a period of five consecutive days. Several different types of incentives were used to ensure that subjects provided the fastest times possible. Two blocks of 25 trials were administered to each subject on each day. A 2 × 2 × 2 × 5 × 2 mixed factorial analysis of variance was used to test for between-subject differences of group (experimental/control), sex, and athletic status and for within-subject differences of days and blocks. The four dependent variables were reaction time (RT) mean, RT consistency, movement time (MT) mean, and MT consistency. Results did not support the classic finding of male superiority over females in RT/MT or athletes' superiority over nonathletes. Evidence of athletic superiority emerged, but for the first day of practice only. As subjects were allowed extended practice over a 5-day test period in which knowledge of results (KR) and other incentives were provided, differences in the experimental groups disappeared. Sex was the predominant factor in consistency, with males being less variable in RT (p = .02) performance than females. There were no sex differences in MT consistency.  相似文献   

17.
Abstract

Quiet eye training (QET) may be a more effective method for teaching children to catch than traditional training (TT) methods, but it is unclear if the benefits accrued persist in the long term. Thirty children were randomly allocated into a QET or TT group and, while wearing a mobile eye tracker, underwent baseline testing, training and two retention tests over a period of eight weeks, using a validated throw and catch task. During training, movement-related information was provided to both groups, while the QET group received additional instruction to increase the duration of their targeting fixation (QE1) on the wall prior to the throw, and pursuit tracking (QE2) period on the ball prior to catching. In both immediate (R1) and delayed (R2, six weeks later) retention tests, the QET group had a significantly longer QE1 duration and an earlier and longer QE2 duration, compared to the TT group, who revealed no improvements. A performance advantage was also found for the QET compared to the TT group at both R1 and R2, revealing the relatively robust nature of the visuomotor alterations. Regression analyses suggested that only the duration of QE1 predicted variance in catch success post-training, pointing to the importance of a pre-programming visuomotor strategy for successful throw and catch performance.  相似文献   

18.
Abstract

The study had two aspects: To determine the effect of warm-up throwing drills (employing “systematic overload”) upon subsequent speed and accuracy of the overarm throw in subjects with widely differing maximum velocities, and to determine the effect of a 6-week overload training (in which the speed and accuracy emphases were systematically varied) upon the speed and accuracy of the overarm throw.

The 60 subjects in the short-range phase of the study, examining the immediate effect of overload warm-up, received experimental treatments consisting of 10-oz., 15-oz., and regulation ball warm-up. The 48 subjects who participated in the long-range or training phase of the study received progressive overload in conjunction with various speed and/or accuracy emphases.

Computer services for this study were granted by the University of Wisconsin Research Committee through funds provided by the National Science Foundation and the Wisconsin Alumni Research Foundation.

The results of the study indicated that performance differences in throwing speed and accuracy, of high and low velocity performers that take place immediately following overload warm-up were statistically not significant. The initial speed and/or accuracy emphasis that was given appeared to have little effect on subsequent performance. The results provided no evidence that the use of a weighted ball resulted in immediate or long-range improvements in throwing speed or in throwing accuracy.  相似文献   

19.
ABSTRACT

Although polo is a well-known equestrian sport, it is fundamentally misunderstood. The purpose of this study was to examine trunk and upper extremity kinematics and segmental velocities during the offside forehand polo swing between male and female athletes. Ten female and 17 male professional polo athletes volunteered. An electromagnetic tracking system collected kinematic data at 100 Hz while participants performed three offside forehand polo swings from a stationary wooden horse. One-way ANOVAs revealed statistically significant differences (p<0.05) in all kinematic variables and segmental velocities. Specifically, males exhibited a greater mean difference (MD=23°) of trunk flexion at take away (TA) and top of backswing (TOB)(MD=29°) trunk lateral flexion at ball contact (BC)(MD=23°), trunk rotation at TA(MD=97°) and TOB(MD=118°), shoulder abduction at TOB(MD=64°), and shoulder elevation at TOB(MD=13°) and BC(MD=40°). Females displayed greater trunk rotation at BC(MD=91°), shoulder elevation at TA(MD=19°), and elbow flexion at TA(MD=90°). Additionally, females generated greater segmental velocities early in the swing, while the males generated velocity later. The movement patterns observed amongst the males suggest energy is being transferred more efficiently along the kinetic chain, thus more efficient swing mechanics, but further investigation into the role of the trunk and lumbopelvic-hip complex in reference to the polo swing is warranted.  相似文献   

20.
Lacrosse requires the coordinated performance of many complex skills. One of these skills is shooting on the opponents’ net using one of three techniques: overhand, sidearm or underhand. The purpose of this study was to (i) determine which technique generated the highest ball velocity and greatest shot accuracy and (ii) identify kinematic and kinetic variables that contribute to a high velocity and high accuracy shot. Twelve elite male lacrosse players participated in this study. Kinematic data were sampled at 250 Hz, while two-dimensional force plates collected ground reaction force data (1000 Hz). Statistical analysis showed significantly greater ball velocity for the sidearm technique than overhand (P < 0.001) and underhand (P < 0.001) techniques. No statistical difference was found for shot accuracy (P > 0.05). Kinematic and kinetic variables were not significantly correlated to shot accuracy or velocity across all shot types; however, when analysed independently, the lead foot horizontal impulse showed a negative correlation with underhand ball velocity (P = 0.042). This study identifies the technique with the highest ball velocity, defines kinematic and kinetic predictors related to ball velocity and provides information to coaches and athletes concerned with improving lacrosse shot performance.  相似文献   

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