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201.
202.
This paper provides tables of critical values for determining statistically significant discrepancies between Wechsler Verbal/Performance IQ and WIAT subtest and composite scores based on a predicted-achievement method. It is recommended that these tables be used when a statistically significant and diagnostically meaningful Verbal IQ-Performance IQ discrepancy exists rendering either of these IQs a better estimate of a student's ability than the Full Scale IQ. Issues regarding the use of discrepancy formulas in the assessment and diagnosis of learning disabilities are discussed, and basic considerations for using the critical values tables are provided.  相似文献   
203.
The on-going Coronavirus disease(COVID-19)outbreak in China has become the world's leading health headline and is causing major panic and public concerns.On January 30,2020,the World Health Organization(WHO)declared that the new coronavirus outbreak is a public health emergency of international concern.1 The virus has already had a direct impact on more than 10 million people in the city of Wuhan and has reached other parts of China as well,posing a health threat of unknown magnitude globally.As of February 8,2020,WHO reported 34,886 confirmed cases of COVID-19 globally,with 34,589 of them occurring in China(including 6101 severe cases and 723 deaths).A total of 288 other confirmed cases(with 1 death)have been reported in 24 countries,including Japan,Australia,Germany,and United States.2 However,these daily estimates are expected to rise even higher as reports from health authorities in China3 are gathered and near real-time updates of the Johns Hopkins virus dashboard are made 4 The outbreak has caused governments in various countries to take swift and protective measures.In China,these included putting cities on lockdown,5 implementing travel wamings/bans and cancellations,6 extending national holidays,and closing schools and postponing classes7.  相似文献   
204.
The influence of sociocultural factors (ethnicity, socioeconomic status, father absence, and family size) on special education eligibility was examined for three ethnic groups. A multiple regression procedure was used to analyze the data on 300 students referred for evaluation and found to be either not eligible for services or eligible for services as mentally retarded or learning disabled. Results indicated that only socioeconomic status and ethnicity made a significant contribution to the prediction of all three groups. Individually, father absence and family size did not contribute to the prediction of special education eligibility. Results of this study suggest that legislative mandates to control for sociocultural factors in the determination of special education eligibility have been only partially successful.  相似文献   
205.
This study aimed to evaluate the effect of simulated training strategies on performance potential in elite short-track speed skaters. Training load and field-based criterion performances from fifteen athletes (10 males, 5 females) were collected over a 3-month training period and the relationship between training loads and performance was computed with a variable dose-response model using a genetic algorithm. Individual simulations of tapers preceded or not preceded by an overload training (OT) were assessed. We obtained a significant correlation between actual and modelled performances (R2 = 0.76 ± 0.07). Regarding model parameters, no significant difference was found between males and females but the time to recover performance tended to be lower in females. Simulations in which the taper parameters were free highlighted that an exponential or a step taper were the most effective for increasing performance compared to a linear taper (p < 0.05). Optimal exponential taper duration after OT was 10.7 ± 2.4d and the optimal load reduction was 75.9 ± 3.7%. OT intensity had the greatest influence on the predicted performance, followed by OT duration, taper decay, and to a lesser extent load reduction during taper and taper duration. Thus, a variable dose-response systems model allows the evaluation of different taper strategies and their potential effect on performance changes.  相似文献   
206.
The present experiment sought to further understanding of the effects of personalised audiovisual stimuli on psychological and psychophysiological responses during exercise in adults with obesity. Twenty-four participants (Mage = 28.3, SD = 5.5 years; MBMI = 32.2, SD = 2.4) engaged in self-paced exercises on a recumbent cycle ergometer and three conditions (sensory stimulation [ST], sensory deprivation [DE], and control [CO]) were administered. Perceptual (attentional focus and perceived exertion), affective (affective state and perceived activation), and psychophysiological (heart rate variability) parameters were monitored throughout the exercise bouts. A one-way repeated measures analysis of variance was used to compare self-reported and psychophysiological variables (main and interaction effects [5 Timepoints × 3 Conditions]). The results indicate that ST increased the use of dissociative thoughts throughout the exercise session (ηp2 = .19), ameliorated fatigue-related symptoms (ηp2 = .15) and elicited more positive affective responses (ηp2 = .12) than CO and DE. Accordingly, personally-compiled videos are highly effective in ameliorating exertional responses and enhancing affective valence during self-paced exercise in adults with obesity. Audiovisual stimuli could be used during the most critical periods of the exercise regimen (e.g., first training sessions) when individuals with obesity are more likely to focus on fatigue-related sensations.  相似文献   
207.
During soccer matches, performance decrements have been reported that relate to both physical abilities and technical skills. To investigate the effects of low-frequency electrical stimulation LFES (VeinoplusSport®, Ad Rem Technology, France) administered during half-time recovery on performance alterations during the second half. Twenty-two highly trained young players undertook a soccer-match simulation (SAFT90). During half-time, they were randomly assigned to LFES group or Placebo group. Each half was split into 3 bouts of 12 minutes. Following each bout, maximal strike speed (MSS), sprint test (ST), maximal sprint accelerations (MA) and metabolic power (MP) were determined in both groups. Arterial (AF) and venous flows (VF) were measured at rest and at the end of half-time. LEFS group exhibited beneficial effects on performance compared to the Placebo group with a likely effect for MSS, ST, MA, and a possible effect for MP. AF and VF increased statistically more in LEFS group compared to Placebo group. The use of specific calf-pump LFES during half-time of a youth simulated soccer match attenuated the decrease in performance during the second half compared to Placebo group. This effect is most marked at the beginning of the second half with regards to explosive parameters.  相似文献   
208.
Background: A distinction is made in Achievement Goal Theory (AGT) between task-oriented (i.e. effort, intra-individual progress, and self-comparison) and ego-oriented (i.e. inter-individual progress and normative comparison) climates. Combining insights from AGT and Self-Determination Theory (SDT), studies in the PE context have shown that a task-oriented climate positively relates to need satisfaction, although the findings regarding the motivating role of an ego-oriented climate are inconsistent. Moreover, little is known about the role of task- or ego-oriented climates in explaining experiences of basic psychological need frustration.

Purpose: Grounded in AGT and SDT, the aim of the present study was to examine if experiences of basic psychological need satisfaction and need frustration can explain why task- and ego-oriented climates elicit positive and negative motivational outcomes in PE, respectively.

Research design: Cross-sectional study.

Method: A sample of 524 secondary school students (51.1% boys, Mage?=?14.51; SD?=?1.81) from five different secondary schools participated in this study. Students reported on their perceptions of task- and ego-oriented climates, motivational regulations, basic psychological need satisfaction, and need frustration, as well as positive and negative outcomes in PE. Structural equation modeling was used to investigate our objective.

Results: We found that a task-oriented climate had a strong and positive relationship with basic psychological need satisfaction, eliciting a bright pathway to autonomous motivation and affective attitude. An ego-oriented climate was positively related to basic psychological need frustration, eliciting a dark pathway to amotivation and boredom. A negative cross-path from task-oriented climate to basic psychological need frustration was also found, while no significant cross-paths were found from ego-oriented climate to basic psychological need satisfaction.

Conclusions: This study provides a better understanding of the mechanisms that explain why task- and ego-oriented climates shape students’ motivational experiences in PE lessons. It is suggested that a task-oriented climate elicits a bright pathway towards more optimal functioning, because it fosters experiences of need satisfaction and buffers against experiences of need frustration. In contrast, an ego-oriented climate is primarily positively related to feelings of need frustration and negative motivational outcomes. Practical implications for PE teacher training are discussed.  相似文献   
209.
In this study, we investigated what drives players to endorse an aggressive style in Swiss ice hockey and football. We selected a sample of 16 players on the basis of their penalty statistics. We used semi-directed retrospective interviews to collect players’; biographic narratives. The results show a socialization process into an aggressive style, supported by the dominant gender and socialization norms of the sport, which is under the influence of the structure of the sports organization. However, there are large differences between players, with only some of them adopting an aggressive style. Although many studies have underlined the influence of moral disengagement, the present results suggest that time also matters and that the diversity of career paths may explain the diversity in attitudes. Socialization differences in the sports field, bodily capital, a career path marked by thwarted reputation are the key factors that drive players to adopt an aggressive style.  相似文献   
210.
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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