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161.
This study examined the effect of limited peripheral vision on the shuttle sprint performance of soccer players. Participants were 14 male soccer players of a student soccer club (M age = 22.1 yr., SD = 1.3 yr.). They performed a repeated shuttle sprint with full and limited peripheral vision. Mean total sprint time and mean turning time increased significantly with limited peripheral vision. It is concluded that only turning during shuttle sprint performance decreases when sprinting with a restricted peripheral field of view, indicating the use of peripheral vision for the control of directional changes while sprinting.  相似文献   
162.
Translating Toulmin Diagrams: Theory Neutrality in Argument Representation   总被引:1,自引:0,他引:1  
The Toulmin diagram layout is very familiar and widely used, particularly in the teaching of critical thinking skills. The conventional box-and-arrow diagram is equally familiar and widespread. Translation between the two throws up a number of interesting challenges. Some of these challenges (such as the relationship between Toulmin warrants and their counterparts in traditional diagrams) represent slightly different ways of looking at old and deep theoretical questions. Others (such as how to allow Toulmin diagrams to be recursive) are diagrammatic versions of questions that have already been addressed in artificial intelligence models of argument. But there are further questions (such as the relationships between refutations, rebuttals and undercutters, and the roles of multiple warrants) that are posed as a specific result of examining the diagram inter-translation problem. These three classes of problems are discussed. To the first class are addressed solutions based on engineering pragmatism; to the second class, are addressed solutions drawn from the appropriate literature; and to the third class, fuller exploration is offered justifying the approaches taken in developing solutions that offer both pragmatic utility and theoretical interest. Finally, these solutions are explored briefly in the context of the Araucaria system, showing the ways in which analysts can tackle arguments either using one diagrammatic style or another, or even a combination of the two.  相似文献   
163.
The model of prevention science advocated by the Institute of Medicine (P. J. Mrazek & R. J. Haggerty, 1994) has not lead to widespread adoption of prevention and promotion programs for four reasons. The model of dissemination of programs to communities fails to consider community and organizational capacity to implement programs, ignores the need for congruence in values between programs and host sites, displays a pro-innovation bias that undervalues indigenous practices, and assumes a simplistic model of how community organizations adopt innovations. To address these faults, researchers should locate, study, and help disseminate successful indigenous programs that fit community capacity and values. In addition, they should build on theoretical models of how locally developed programs work to make existing programs and polices more effective.  相似文献   
164.
There is evidence that personal experience with trauma is associated with increases in both personal and comparative risk perception. This study investigates this relation in terms of sexual victimization among women, focusing on three potential mediators: perceived control over sexual assault, perceived similarity to a typical sexual assault victim, and psychological distress. Mediational analyses were investigated using structural equation modeling. Although victimization experience was not related to comparative risk perception, it was associated with greater personal risk perception. This relation was mediated by perceived similarity to a typical sexual assault victim. Prospective analyses indicated that personal risk perception does change in response to sexual victimization but also indicated that heightened risk perception may be an accurate assessment of risk that actually precedes victimization experience. Implications for the meaning of perceived similarity and perceptions of risk for sexual assault victims are discussed.  相似文献   
165.
Three conditioned taste aversion experiments with rats investigated superconditioning. In each experiment, alternate exposures of 2 flavor compounds with a common element (i.e., AB/AS) were administered to establish an inhibitory relationship between the 2 unique elements, B and S, and prior to testing, S was paired with lithium chloride (LiCl). In Experiment 1, pairings of a neutral cue (X) with S in compound with B after the AB/AS exposures resulted in superconditioning between X and S. Extinction of the common element (A) just before the S-LiCl pairing attenuated both the inhibitory relationship between B and S (Experiment 2) and superconditioning between X and S (Experiment 3). These observations suggest that superconditioning consists of enhanced performance rather than enhanced associative acquisition.  相似文献   
166.
Three studies examine the psychometric properties (i.e., the test-retest reliability, convergent, and discriminant validity) of Fraley, Waller, and Brennan's Revised Experiences in Close Relationships (ECR-R) self-report measure of romantic attachment anxiety (model of self) and avoidance (model of others). Longitudinal analyses suggest that the ECR-R provided highly stable indicators of latent attachment during a 3-week period (85% shared variance). Hierarchical linear modeling analyses further validated the ECR-R, suggesting that it explained between 30% to 40% of the between-person variation in social interaction diary ratings of attachment-related emotions experienced during interactions with a romantic partner and only 5% to 15% of that in interactions with family and friends. Guidelines are offered regarding the conditions where highly reliable and precise measures of romantic attachment, such as the ECR-R, are deemed necessary and where shorter, albeit slightly less reliable measures, such as Bartholomew and Horowitz's Relationship Questionnaire, may also be viable.  相似文献   
167.
In the analysis of stimulus competition in causal judgment, 4 variables have been frequently confounded with respect to the conditions necessary for stimuli to compete: causal status of the competing stimuli (causes vs. effects), temporal order of the competing stimuli (antecedent vs. subsequent) relative to the noncompeting stimulus, directionality of training (predictive vs. diagnostic), and directionality of testing (predictive vs. diagnostic). In a factorial study using an overshadowing preparation, the authors isolated the role of each of these variables and their interactions. The results indicate that competition may be obtained in all conditions. Although some of the results are compatible with various theories of learning, the observation of stimulus competition in all conditions calls for a less restrictive reformulation of current learning theories that allows similar processing of antecedent and subsequent events, as well as of causes and effects.  相似文献   
168.
Responses to the 1999 Youth Risk Behavior Survey including suicide ideation, attempt, medically treated attempt, and six problem behaviors were analysed. Youth across the spectrum ideated. Overwhelmingly, the 17% of youth with more than three problem behaviors were the youth who acted; they accounted for 60% of medically treated suicidal acts. Compared to adolescents with zero problem behaviors, the odds of a medically treated suicide attempt were 2.3 times greater among respondents with one, 8.8 with two, 18.3 with three, 30.8 with four, 50.0 with five, and 227.3 with six. A count of problem behaviors offers a reliable way to identify suicide risk.  相似文献   
169.
Some children living with life-shortening medical conditions may wish to attend school without the threat of having resuscitation attempted in the event of cardiopulmonary arrest on the school premises. Despite recent attention to in-school do-not-attempt-resuscitation (DNAR) orders, no assessment of state laws or school policies has yet been made. We therefore sought to survey a national sample of prominent school districts and situate their policies in the context of relevant state laws. Most (80%) school districts sampled did not have policies, regulations, or protocols for dealing with student DNARs. A similar majority (76%) either would not honor student DNARs or were uncertain about whether they could. Frequent contradictions between school policies and state laws also exist. Consequently, children living with life-shortening conditions who have DNARs may not have these orders honored if cardiopulmonary arrest were to occur on school premises. Coordinated efforts are needed to harmonize school district, state, and federal approaches in order to support children and families' right to have important medical decisions honored.  相似文献   
170.
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