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11.
Ball screens are one of the most frequently used tactical behaviour in elite basketball games. The aim of the present study was to identify their predictors of success related to time, space, players, and tasks performed. The sample was composed of 818 ball screens corresponding to 20 close games (mean differences in score of 3.1 ± 0.8 points) randomly selected from the playoff games of the Spanish Basketball League (2008–2011). Classification tree analysis (CHAID) was used to analyse which variable or combination of variables, better predicts effectiveness during ball screens. The main results allowed identifying interactions with dribbler actions after the screen and the orientation of the screen on the ball. The results showed no interaction with game quarter and quarter minute temporal-related variables in both analyses. The present findings allow improving coaches’ strategic plans that involve selecting the most appropriate offensive approach when performing ball screens.  相似文献   
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Infant vocalizations are early-emerging communicative markers shown to be atypical in autism spectrum disorder (ASD), but few longitudinal, prospective studies exist. In this study, 23,850 infant vocalizations from infants at low (LR)- and high (HR)-risk for ASD (HR-ASD = 23, female = 3; HR-Neg = 35, female = 13; LR = 32, female = 10; 80% White; collected from 2007 to 2017 near Philadelphia) were analyzed at 6, 12, and 24 months. At 12 months, HR-ASD infants produced fewer vocalizations than HR-Neg infants. From 6 to 24 months, HR-Neg infants demonstrated steeper vocalization growth compared to HR-ASD and LR infants. Finally, among HR infants, vocalizing at 12 months was associated with language, social phenotype, and diagnosis at age 2. Infant vocalizing is an objective behavioral marker that could facilitate earlier detection of ASD.  相似文献   
14.
In this paper strict, non-smooth Lyapunov functions for some non-homogeneous versions of the super-twisting algorithm are proposed. Convergence under the action of bounded perturbations for two basic forms of non-homogeneous algorithms will be studied by means of the Lyapunov functions. Since the homogeneity property cannot be used directly to prove stability of the algorithms, the availability of a Lyapunov function is of great importance for analysis and design in these cases. Moreover, exponential or finite-time and local or global stability are required to be established, since they are not derived from the homogeneity.  相似文献   
15.
The problem of constructing functional observers for linear systems with unknown inputs is considered. Necessary and sufficient conditions for the existence of a proper observer (without differentiations) are revisited. A simple and explicit form of a functional observer is presented. It is shown that when such observer is not proper, it is still possible to use the High-Order Sliding Mode differentiator to implement it. Nevertheless, in such case, additional conditions on the system and the unknown input are required.  相似文献   
16.
A supply chain consists of different processes and when conducting supply chain re-design is necessary to identify the relevant processes and select a target for re-design. Through a literature review a solution is presented here to identify first the relevant processes using the Supply Chain Operations Reference (SCOR) model, then to use Analytical Hierarchy Process (AHP) analysis for target process selection. AHP can aid in deciding which supply chain processes are better candidates to re-design in light of predefined criteria.  相似文献   
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When implementing environmental education and interventions to promote one pro-environmental behavior, it is seldom asked if and how non-target pro-environmental behaviors are affected. The spillover effect proposes that engaging in one behavior affects the probability of engagement or disengaging in a second behavior. Therefore, the positive spillover effect predicts that interventions targeting one specific behavioral have the capacity to promote non-targeted and/or future pro-environmental behaviors. However, the negative spillover effect predicts that engaging in a first pro-environmental behavior will prevent or decrease a second pro-environmental behavior. Since the theoretical and empirical basis for positive and negative spillover effects are not sufficiently understood, the present paper (1) suggests a distinction between behavioral, temporal, and contextual spillovers (2) reviews the existing spillover research literature across a variety of environmental domains, (3) presents potential moderators governing the direction of spillover effects, and finally (4) discuss techniques to promote pro-environmental spillovers.  相似文献   
19.
Even though peer tutors are often used in gross anatomy courses, research in the field is rather a subject of the last two decades. This is especially true about the didactical challenges these types of peer tutors experience during their tutorials and about how they are prepared for the task. The aim of the presented study was to learn about the training needs of the tutors, and to subsequently design, implement, and evaluate a didactical training concept. A qualitative design was chosen to examine how tutors can best be prepared for tutorials of gross anatomy. To do so, focus group interviews were conducted. The data were analyzed and grouped into various concepts, using semi‐structured interview questions as guidance. It was found that peer tutors are in need of training in the following aspects: Dealing with students who are experiencing difficulties during or as a result of dissection, dealing with group dynamics, that is, at the dissection table, keeping students motivated, time management, and staying confident as a tutor. In order to be regarded as useful and relevant in the eyes of tutors, a preparatory training course should include all these aspects in addition to general didactical training elements. Training needs of peer tutors of gross anatomy go beyond the content of standardized didactical curricula; therefore, tutors should be prepared with a curriculum that is specifically geared toward the many challenges associated with teaching gross anatomy to first year medical students which are already so well documented in the research literature. Anat Sci Educ 10: 495–502. © 2017 American Association of Anatomists.  相似文献   
20.
The aim of this study was to assess the effects of quality of opposition and match status on technical and tactical volleyball performances, as measured by block, attack, serve, and set actions related to the tasks, space, players, and efficacy of selected game actions. Twenty-five matches from the men's World Cup 2007 were notated and through cluster analysis were classified as "high" (HIGH), "intermediate" (INT) or "low" (LOW) quality. The difference between points scored and points allowed was used to define match status. Multinomial logistic regression identified an association of match status with: set direction (likelihood ratio test [LRT]?=?15.5, P?=?0.017) and block typology (LRT?=?9.6, P?=?0.047) in HIGH vs. HIGH matches; attack player (LRT?=?17.4, P?=?0.026) and block typology (LRT?=?9.2, P?=?0.010) in LOW vs. LOW matches; and serve type (LRT?=?17.4, P?=?0.002), block strategy (LRT?=?53.7, P?<0.001), and serve efficacy (LRT?=?26.0, P?=?0.001) in HIGH vs. LOW matches. Results suggest that volleyball teams took more risky decisions in unbalanced situations. They also carried less risk through technical and tactical decisions in balanced and moderate situations whether they had the advantage or not. Therefore, strategic behaviour was affected by the interaction of quality of opposition and match status, providing a better understanding of volleyball game performance and new insights for practice, competition, and research.  相似文献   
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