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1.

Objectives

This study aimed to explain how defenders intercept the trajectory of a passing ball by understanding how they coupled their actions to critical information sources in a competitive performance setting in team sports.

Design

Time series data on movement displacements of fifteen senior male futsal performers were recorded and digitized during nine competitive futsal games.

Method

Performance was recorded by a digital camera and digitized with TACTO software. The spatial-temporal dynamics of performers during ten intercepted and ten non-intercepted passes were compared. Time to ball interception was calculated by the difference between the time of each defender to an interception point in ball trajectory and the time of the ball’s arrival at the same interception point. Initial distances between defenders and ball and velocity data of defenders and ball over time were also recorded.

Results

Time to ball interception revealed positive values when passes were not intercepted, and negative to zero values when passes were intercepted. At the moment of pass initiation defenders’ distances to the ball constrained their possibilities for successful interception. Analysis of defenders’ adaptations to the environment revealed that continuous changes in the defenders’ velocities constrained their success of the interception.

Conclusions

Intercepted passes seemed to be influenced by the continuous regulation of a defender’s velocity relative to the ball’s trajectory. Time to ball interception is a variable that captured the emergent functional behaviours of players attempting to intercept the trajectory of a pass in the team sport of futsal.  相似文献   

2.
Although creativity is helpful if not needed to deal with conflicts, research on the effects of conflict on creativity shows inconsistent findings. In this study, the possibility that effects may depend on people’s role in conflict was considered. Whether, when, and why assuming the role of attacker or defender in conflict affects creative idea generation was therefore investigated. The prediction was tested if attackers are more creative than defenders. In addition, control over the situation as a moderating variable and anxiety as a mediator were considered. Participants (n = 115, Mage = 22.06, SDage = 2.75, 83 women) were recruited in Amsterdam, the Netherlands, and were randomly assigned to an attacker, defender, or role control condition. Controllability over the situation was manipulated within-subjects and anxiety and creativity were measured during 2 rounds of idea generation. Results revealed no differences in creative performance and anxiety between defenders and attackers and that defenders generated a greater number of ideas than people in the role control condition. Exploratory analyses further revealed that attackers and defenders generated a greater number of aggressive ideas. Finally, attackers and defenders experienced more anxiety, but increased anxiety did not account for observed differences in the number of (aggressive) ideas. The effect of controllability could not be investigated due to a failed manipulation. Limitations and implications are discussed.  相似文献   

3.
This study examined the continuous interpersonal interactions of performers in dyadic systems in team sports, as a function of changing information constraints. As a task vehicle, we investigated how attackers attained success in 1v1 sub-phases of basketball by exploring angular relations with immediate opponents and the basket. We hypothesized that angular relations would convey information for the attackers to dribble past defenders. Four basketball players performed as an attacker and defender in 1v1 sub-phases of basketball, in which the co-positioning and orientation of participants relative to the basket was manipulated. After video recording performance behaviors, we digitized participant movement displacement trajectories and categorized trials as successful or unsuccessful (from the attackers’ viewpoint). Results revealed that, to successfully dribble past a defender, attackers tended to explore the left hand side of the space by defenders by increasing their angular velocity and decreasing their angular variability, especially in the center of the court. Interpersonal interactions and goal-achievement in attacker–defender dyads appear to have been constrained by the angular relations sustained between participants relative to the scoring target. Results revealed the functionality of exploratory behaviors of participants attempting re-align spatial relations with an opponent in 1v1 sub-phases of team games.  相似文献   

4.
Principles of conspecific defense have been analyzed for rodents, in which specific target sites for biting by attackers on defenders serve as an important determinant of the actions involved in both attacker and defender behavior. In an effort to determine the generality of these principles, attack and defensive behaviors and target sites for biting attack were evaluated in a nonrodent species, the tree shrew (Tupaia belangeri). Brief daily and repeated conspecific dyadic encounters between adult, socially experienced males (dominants, attackers), and adult, socially naive males (subordinates, defenders) that had been transferred into the territory of the dominants, produced a polarization of attack and defense. The dominant males showed chase, chase attack, jump attack, and biting behaviors, while the subordinates displayed flight and freezing. The vast majority of bites, as well as wounds and bruises, were on the subordinates’ backs. These patterns are very similar to those previously found in rats and mice and suggest that the organization of fighting, with targets of biting (or other painful) attack serving as an important determinant of both attacker (dominant) and defender (subordinate) behavior, may show considerable generality across nonrodent as well as rodent species. Although relatively few wounds were found after 28 days of repeated and daily encounters, the subordinate tree shrews show a variety of behavioral, neuroendocrine, and central nervous changes, indicating that they are stressed by these encounters per se. Aggr. Behav. 27:139–148, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   

5.

Objective

This study examined the contributions of maternal bids for joint attention, relationship quality, and infant characteristics, to individual differences in infants’ parallel and joint attention.

Method

Fifty-two 10-month-olds and their mothers were assessed in order to investigate concurrent predictors of infant parallel attention, responding to joint attention, and initiating joint attention.

Results

Parallel attention was predicted by infants’ higher mental development, low expression of negative emotionality, and maternal entertaining behaviors. Responding to joint attention was marginally predicted by total maternal bids for joint attention. Initiating joint attention was predicted by the infants’ low expression of negative emotionality, as well as marginally predicted by fewer maternal teaching behaviors.

Conclusion

These results further the understanding of the factors influencing infant parallel as well as joint attention.  相似文献   

6.

Purpose

We propose that constant exposure to advances in technology has resulted in an implicit association between technology and success that has conditioned decision makers to be overly optimistic about the potential for technology to drive successful outcomes. Three studies examine this phenomenon and explore the boundaries of this “technology effect.”

Design/Methodology/Approach

In Study 1, participants (N = 147) made simulated investment decisions where the information about technology was systematically varied. In Study 2 (N = 143), participants made decisions in a resource dilemma where technology was implicated in determining the amount of a resource available for harvest. Study 3 (N = 53 and N = 60) used two implicit association tests to examine the assumption that people associate technology with success.

Findings

Results supported our assumption about an implicit association between technology and success, as well as a “technology effect” bias in decision making. Signals of high performance trigger the effect, and the effect is more likely when the technology invoked is unfamiliar.

Implications

Excessive optimism that technology will result in success can have negative consequences. Individual investment decisions, organizational decisions to invest in R&D, and societal decisions to explore energy and climate change solutions might all be impacted by biased beliefs about the promise of technology.

Originality/Value

We are the first to systematically examine the optimistic bias in the technology effect, its scope, and boundaries. This research raises decision makers’ awareness and initiates research examining how the abstract notion of technology can influence perceptions of technological advances.
  相似文献   

7.

Purpose

The aim of the present research was to investigate how a negative decision outcome generated by a leader in a hasty, timely, or delayed manner impacts upon the need for, and the effectiveness of apologies to restore followers’ trust.

Design/Methodology/Approach

Data were collected using five studies in which the effects of timing of an incorrect decision on the trust repair process were investigated.

Findings

In the aftermath of a leader’s failure, followers experienced a delayed incorrect decision as a more severe transgression than a hasty or a timely incorrect decision. This effect was mediated by procedural fairness concerns (Study 1). The present findings also revealed an interesting paradox. Specifically, in the delayed condition followers expressed the highest need for an apology (Studies 2 and 3), but at the same time expected an apology to be less effective for enhancing trustworthiness than in the timely and the hasty condition (Study 3). Moreover, we also showed that the actual provision of an apology was effective for restoring both trustworthiness (Study 4) and trust (Studies 4 and 5) in the timely and the hasty condition, but ineffective in the delayed condition.

Implications

The present research shows that when the outcome of a decision is uncertain, it is better to make a decision (too) soon rather than (too) late.

Originality/Value

Despite the ubiquity of timing errors in daily life, our studies are the first to focus on the role of timeliness of decisions in the trust repair process.
  相似文献   

8.
9.
We conducted four experiments to investigate skilled typists’ explicit knowledge of the locations of keys on the QWERTY keyboard, with three procedures: free recall (Exp.?1), cued recall (Exp.?2), and recognition (Exp.?3). We found that skilled typists’ explicit knowledge of key locations is incomplete and inaccurate. The findings are consistent with theories of skilled performance and automaticity that associate implicit knowledge with skilled performance and explicit knowledge with novice performance. In Experiment?4, we investigated whether novice typists acquire more complete explicit knowledge of key locations when learning to touch-type. We had skilled QWERTY typists complete a Dvorak touch-typing tutorial. We then tested their explicit knowledge of the Dvorak and QWERTY key locations with the free recall task. We found no difference in explicit knowledge of the two keyboards, suggesting that typists know little about key locations on the keyboard, whether they are exposed to the keyboard for 2 h or 12 years.  相似文献   

10.
Despite the benefits of physical activity for youth with cystic fibrosis (CF) and congenital heart disease (CHD), most are insufficiently active. More information is required on how to facilitate physical activity in these populations. Although there are no studies that provide information about participation in CF and CHD youth from the perspective of parents, the involvement of caregivers may be an important facilitator to physical activity in youth with chronic diseases.

Objective

This qualitative study explored how the parents of youth with CF and CHD experience physical activity, and parents commented on both their own and their child’s physical activity.

Methods

Twenty-nine parents from a CHD and CF clinic participated in a semi-structured interview, and a thematic analysis of the transcribed data was undertaken.

Results

Parents discussed the numerous benefits and barriers associated with physical activity for both child and self. Role modeling was a critical social process to overcoming barriers. Parents experiences were situated within the broader family context characterized by a prevailing sense of stress and complexity.

Conclusion

By illustrating how the parents of youth with CF and CHD understand the role of physical activity in their and their child’s life, this study provides valuable information regarding the development of interventions to increase physical activity among children with CF and CHD.  相似文献   

11.

Background

In this study we compared the effect of different emotion regulation strategies on positive and negative emotions in patients with borderline personality disorder.

Methods

Emotion regulation strategies were a distracting task, individual positive memory imagery, individual soothing imagery, and a neutral comparison condition. During two separate sessions, 17 participants watched either neutral or negative movie segments before using these strategies.

Results

All three strategies influenced emotions into a favorable direction as compared to the neutral comparison condition. The positive memory image increased positive emotions significantly stronger than counting colors and distracting.

Discussion

Different strategies seem to have similar effects in decreasing negative emotions. Positive emotions may be affected in particular by positive and soothing imagery techniques.  相似文献   

12.
A check detection task in a 5 × 5 section of the chessboard, containing a King and one or two potential checking pieces was employed. The checking status (i.e., the presence or absence of a check) and the number of attackers (one or two) were manipulated. It was found that the reaction time cost for adding a distractor was differentially greater inno trials thanyes trials for novice, but not for expert, chess players. In addition, we contrasted standard check detection trials with trials in which one of two attackers was cued (colored red) and the task was to determine the checking status of the cued attacker while ignoring the other attacker. We documented a Stroop-like interference effect on trials in which a cued nonchecking attacker appeared together with an attacker that was checking (i.e., incongruent). These findings suggest automatic and parallel encoding procedures for chess relations in experts.  相似文献   

13.
Affordances have recently been proposed as a guiding principle in perception–action research in sport (Fajen, Riley, & Turvey, 2009). In the present study, perception of the ’passability’ affordance of a gap between two approaching defenders in rugby is explored. A simplified rugby gap closure scenario was created using immersive, interactive virtual reality technology where 14 novice participants (attacker) judged the passability of the gap between two virtual defenders via a perceptual judgment (button press) task. The scenario was modeled according to tau theory (Lee, 1976) and a psychophysical function was fitted to the response data. Results revealed that a tau-based informational quantity could account for 82% of the variance in the data. Findings suggest that the passability affordance in this case, is defined by this variable and participants were able to use it in order to inform prospective judgments as to passability. These findings contribute to our understanding of affordances and how they may be defined in this particular sporting scenario; however, some limitations regarding methodology, such as decoupling perception and action are also acknowledged.  相似文献   

14.

Objectives

This study explored the relationship between social control and behavior by examining both the antecedents of social control use following a physical activity lapse as well as the behavior reaction to the use of social control.

Design

As part of a larger project, high school students (N = 547) were prospectively followed over the course of a year and reported physical activity every two months.

Methods

For this study, 123 adolescents who reported experiencing a physical activity lapse sometime during the year were selected. Family physical activity and adolescent activity prior to the lapse were used to predict family use of social control tactics following the lapse. Use of social control tactics were used to differentiate whether adolescents increased their activity following the lapse or not.

Results

Results revealed that family physical activity predicted use of positive and collaborative social control following an adolescent activity lapse. Adolescent physical activity prior to the lapse also predicted parental use of collaborative social control following the lapse. In terms of the adolescent’s behavior reaction, an increase in collaborative social control following the lapse appeared to differentiate those who reported an increase in activity following the lapse compared with those who reported no increase.

Conclusions

This study provided support for physical activity behavior being both an antecedent and consequence of parental social control.  相似文献   

15.
Shared service centers and professional employability   总被引:1,自引:0,他引:1  
This paper presents case study evidence of evolutionary changes in business support functions resulting in a fundamental hollowing out of the professional space over time and distance, creating the ‘hourglass’ profession. In an IT-enabled, boundaryless world, many professional activities can now be undertaken, in the manner of the Martini slogan, ‘any time, any place, anywhere’.This paper aims:
  • To investigate the shared service center as an emerging organizational form with the potential to drive fundamental change in the nature and location of professional work.
  • To explore the impact of these changes for individual professional workers, and to highlight the need for a greater focus on individual employability as the driver of an overall career trajectory.
  相似文献   

16.

Objective

The current study examined the efficacy of an early intervention based on acceptance and commitment therapy (ACT) for depressive symptomatology. The ACT intervention is aimed at increasing the acceptance of negative thoughts and emotions and living a mindful and value-based life.

Method

Adults with mild to moderate depressive symptomatology were randomly assigned to the ACT intervention (n = 49) or to a waiting list (n = 44). The mean age of the participants was 49 years. The majority of the participants was female and of Dutch origin. All the participants completed measures before and after the intervention, as well as three months later at follow-up to assess depression (CES-D), anxiety (HADS-A), fatigue (CIS), alcohol use and acceptance (AAQ-II).

Results

The ACT intervention led to statistically significant reduction in depressive symptomatology (Cohen’s d = .60). These reductions were maintained at the three-month follow-up. Also significant reductions in anxiety and fatigue were observed. Moreover, mediational analysis showed that the improvement of acceptance during the intervention mediated the effects of the intervention on depressive symptomatology at follow-up.

Conclusion

These findings suggest that an early intervention based on ACT, aimed at increasing acceptance, is effective in reducing depressive symptomatology.  相似文献   

17.
R. E. Jennings 《Topoi》1994,13(1):3-10
I argue that the conjunctive distribution of permissibility over or, which is a puzzling feature of free-choice permission is just one instance of a more general class of conjunctive occurrences of the word, and that these conjunctive uses are more directly explicable by the consideration that or is a descendant of oper than by reference to the disjunctive occurrences which logicalist prejudices may tempt us to regard as semantically more fundamental. I offer an account of how the disjunctive uses of or may have come about through an intermediate discourse-adverbial use of or, drawing a parallel with but, which, etymologically, is disjunctive rather than conjunctive and whose conjunctive uses seem to represent just such a discourse-adverbial application.  相似文献   

18.

Background

Although animal research ethics committees (AREC) are well established in Western countries, this field is weakly developed and its concept is poorly understood in the Middle East and North Africa region.

Objective

Our main objective was to introduce the concept and requirements of ethical approaches in dealing with experimental animal in research and teaching in Egypt.

Methods

Due to its very recent inception, Cairo University, Faculty of Science IACUC decided to operate in accordance with Guide for the Care and Use of Laboratory Animals 8th Edition 2011 (the Guide) since Egypt has not yet compiled its own guide.

Results

Fifty protocols were reviewed in 2013–2014. Only ten protocols were reviewed in 2013, but in 2014, forty protocols were reviewed. In 2013 all protocols were approved and in 2014, number of approvals were 35, the number of deferrals were 4, and one refused protocol. Master’s theses (MSc) research protocols constituted the majority of the total reviewed protocols. This is attributed to the decision of the Board of the Faculty of Science, Cairo University in September, 2013 that the approval of the IACUC is mandatory before conducting any research involving animals or theses registration.

Conclusion

The first IACUC was established in the Cairo University, Faculty of Science, since 2012. The challenges encountered by the committee were diverse, such as the absence of laws that control the use of animal models in scientific research, lack of guidelines (protocols for experimental animals in research) and, mandatory ethical approval for any experimental animal research.
  相似文献   

19.
Decision-making requires the perception of relevant information variables that emerge from the player–environment interaction. The purpose of the present article is to empirically assess whether players’ decisional behavior about which type of pass to make is influenced by the spatio-temporal variable tau. Time series positional data of rugby players were analyzed from video footage taken in real match scenarios. The tau of the distance motion gap between attacker and defender was calculated, along with the duration of the next pass. Results revealed that the initial tau value predicted 64% of the variance found in pass duration. A qualitative distinction of tau dynamics between two periods of the approach between the attacker and the defender was also observed. We argue that the time-to-contact between the attacker and the defender may yield information about future pass possibilities. Additionally, the informational fields constraining attacker–defender interaction may be viewed as a convergent channeling of possibilities towards a single pass solution.  相似文献   

20.

Objective

The purpose of this study was to synthesize findings from motivational climate interventions employing [Ames, 1992a] and [Ames, 1992b] and [Epstein, 1988] and [Epstein, 1989] TARGET framework within school-based physical education contexts.

Design

The present study employed a quantitative research synthesis design. Meta-analysis uses empirical studies to summarize past research by drawing overall conclusions from separate investigations. This research design highlights important and unsolved issues related to motivational climate interventions within physical education.

Methods

Standard meta-analytic procedures incorporating inclusion and exclusion criteria, literature search, coding procedures, and statistical methods were used to identify and synthesize 22 studies with 24 independent samples. Cohen’s (1988) criteria for effect sizes were used to interpret and evaluate results.

Results

There was an overall small positive treatment effect (g = 0.103) for groups exposed to mastery motivational climates. Outcome analyses identified the most consistent and largest overall treatment effects for behavioral outcomes (g = 0.39–0.49) followed by affective outcomes (g = −0.27 to 0.59) and cognitive outcomes (g = −0.25 to 0.32). Moderator analyses were directed by study heterogeneity and identified several trends in intervention features and study features with the most substantial trend for participant features as elementary students had the largest overall treatment effect (g = 0.41).

Conclusions

Outcome and moderator analyses identified several trends in methodological features, participant features, and study features that should be addressed in future physical education motivational climate interventions.  相似文献   

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