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861.
Describes (a) the effects of a social-influences-based drug prevention program (the Midwestern Prevention Project) on the mediating variables it was designed to change and (b) the process by which the effects on mediating variables changed use of drugs (tobacco, alcohol, and marijuana). Students in 42 middle schools and junior high schools in Kansas City, Missouri, and Kansas City, Kansas, were measured in the fall of 1984 (N = 5,065) and again 1 year later (N = 5,008) after 24 of the schools had been through the program. Compared to students in control schools, students in program schools became less likely to express belief in the positive consequences of drug use, less likely to indicate that they would use such drugs in the future, more likely to report that their friends were less tolerant of drug use, and more likely to believe that they were better able to communicate with their friends about drug or school problems. Change in perceptions of friends' tolerance of drug use was the most substantial mediator of program effects on drug use. There was evidence that intentions to use and beliefs about the positive consequences of use may also mediate program effects on drug use.  相似文献   
862.
Social influences on smoking uptake were examined in latent growth curve analyses of data from 1,320 youths assessed 5 times during 6th to 9th grade. Initial smoking stage predicted increases in number of friends who smoked, indicating selection; however, initial number of friends who smoked did not predict smoking stage progression, indicating no significant effect of socialization. Associations over time among smoking stage progression, affiliation with friends who smoke, and parenting behaviors were significant, suggesting dynamic, reciprocal relationships. Parental involvement, monitoring, and expectations provided direct protective effects against smoking progression as well as indirect effects, by limiting increases in number of friends who smoke. These results are consistent with the peer selection hypothesis, confirm the powerful association over time of social influences with smoking, and provide the first evidence that parenting behavior may protect against smoking progression by limiting increases in number of friends who smoke.  相似文献   
863.
    
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864.
Book review     

Raison et déraison d'État. Théoriciens et theories de la raison d'État aux XVIe et XVIIe siècles sous la direction de Yves Charles Zarka Paris, Presses Universitaires de France, 1994 pp. 436, 248 FF. ISBN 9–782130–461616.

Beverly C. Southgate: ’Covetous of Truth’: The Life and Work of Thomas White, 1593–1676 Dordrecht: Kluwer Academic Publishers, 1993. 189 pp. £60.00 ISBN 0–7923–1926–5

George Dicker: Descartes: An Analytical and Historical Introduction Oxford University Press, 1993 (248 pp.) £14.95 pbk. ISBN 0–19–507590–0

Theo Verbeek: Descartes and the Dutch: Early Reactions to Cartesian Philosophy, 1637–1650. Carbondale and Edwardsville, Southern Illinois University Press, 1992, x + 168 pp. $30.00 ISBN 0–8093–1617‐X

David Berman: George Berkeley: Idealism and the Man Oxford University Press, 1994. £27.50 ISBN 0–19–826746–0

Joseph Mali: The Rehabilitation of Myth: Vico's New Science Cambridge: Cambridge University Press, 1992. pp. xv + 275. £35.00 ISBN 0–521–41952–2

R. C. Solomon and K. W. Higgins (eds): The Age of German Idealism Routledge: London, 1993. Pp. 408. £55.00 (hbk) ISBN 0–415–05604–7

T. L. S. Sprigge: James and Bradley: American Truth and British Reality Chicago and La Salle, Illinois: Open Court, 1993 Pp. xiv + 630. $66.95 (hbk), $29.95 (pbk). ISBN 0–8126–9227–6 (pbk)

A. W. Moore: The Infinite Routledge, London and New York (1990). First published in paperback, 1991. xiv + 268 pp., £10.99 ISBN 0–415–07048–1  相似文献   
865.
While velocity generation is an obvious prerequisite to proficient tennis serve performance, it is also the only stroke where players are obliged to negotiate a unique target constraint. Therefore, the dearth of research attending to the accuracy component of the serve is surprising. This study compared the body, racquet and ball kinematics characterising successful serves and service faults, missed into the net, in two groups of elite junior female players and one professional female tennis player. Three-dimensional body, racquet and ball kinematics were recorded using a 22-camera VICON motion analysis system. There were no differences in body kinematics between successful serves and service faults, suggesting that service faults cannot be attributed to a single source of biomechanical error. However, service faults missing into the net are characterized by projection angles significantly further below the horizontal, implying that consistency in this end-point parameter is critical to successful performance. Regulation of this parameter appears dependent on compensatory adjustments in the distal elbow and wrist joints immediately prior to impact and also perceptual feedback. Accordingly, coordination of the distal degrees of freedom and a refined perception-action coupling appear more important to success than any isolated mechanical component of the service action.  相似文献   
866.
The item-specific proportion congruency (ISPC) effect is consistent with the idea that control processes can be applied rapidly in accord with previously experienced conflict for a particular category. An alternative account of this effect is that it reflects item-specific learning processes unrelated to control at the level of the category. The accounts predict the same behaviour but differ in terms of electrophysiological predictions. Two experiments examined the ISPC effect with a particular focus on neural correlates that might reveal whether, and how early in processing, high and low proportion congruent items are treated as distinct classes of stimuli. For both tasks, the proportion congruency category was distinguished prior to the congruence of the specific stimulus, as early as 100 ms post-stimulus onset for the global/local identification task (Experiment 1) and 150 ms for the Stroop task (Experiment 2). The results support an on-line control account of ISPC effects.  相似文献   
867.
The adolescent children of depressed mothers are at increased risk for depression, but little is known about protective factors for these children. Maintenance of positive affect in a stressful context may be an important marker of resilience. Mothers with (n = 34) and without (n = 38) a history of depression and their adolescent children completed questionnaires regarding adolescents’ coping and depressive symptoms and engaged in a 15 min videotaped interaction about family stress. Adolescents’ observed behaviors were coded using the Iowa Family Interaction Rating Scales. No significant differences emerged in observed behavior between adolescents of mothers with and without a history of depression. Higher levels of primary and secondary control coping and lower levels of disengagement coping were related to higher levels of observed positive mood and fewer depressive symptoms in adolescents. Observed positive mood was related to fewer depressive symptoms in adolescents, even after accounting for maternal history of depression and current maternal depressive symptoms. Results suggest the importance of considering positive affect in the context of family stress as a marker of resilience in adolescents at risk for depression. The current study provides evidence for coping as a protective factor, related to higher levels of positive affect and fewer depressive symptoms, in adolescents exposed to maternal depressive symptoms.  相似文献   
868.
This study examined the association among caregivers' five-factor personality traits and subjective health with particular emphasis on the role of two theoretically implicated mediators: multi-domain self-efficacy and caregiver strain. The sample comprised 536 informal caregivers (mean age = 62.9 years, SD = 19.9, 72% female, 98% White) of community-dwelling older adults with multiple functional impairments. Both physical health and mental health were negatively associated with neuroticism and positively associated with extraversion and conscientiousness. Agreeableness and openness were associated with better subjective mental health and physical health, respectively. Multiple mediation analyses indicated that self-efficacy mediated all observed associations between personality and subjective health, whereas caregiver strain selectively mediated the associations of neuroticism and agreeableness with mental health.  相似文献   
869.
The heterogeneity of schizophrenia remains an obstacle for understanding its pathophysiology. Studies using a tone discrimination screening test to classify patients have found evidence for 2 subgroups having either a specific deficit in verbal working memory (WM) or deficits in both verbal and nonverbal memory. This study aimed to (a) replicate in larger samples differences between these subgroups in auditory verbal WM; (b) evaluate their performance on tests of explicit memory and sustained attention; (c) determine the relation of verbal WM deficits to auditory hallucinations and other symptoms; and (d) examine medication effects. The verbal WM and tone discrimination performance did not differ between medicated (n = 45) and unmedicated (n = 38) patients. Patients with schizophrenia who passed the tone screening test (discriminators; n = 60) were compared with those who did not (nondiscriminators; n = 23) and healthy controls (n = 47). The discriminator subgroup showed poorer verbal WM than did controls and a deficit in verbal but not visual memory on the Wechsler Memory Scale-Revised (Wechsler, 1987), whereas the nondiscriminator subgroup showed overall poorer performance on both verbal and nonverbal tests and a marked deficit in sustained attention. Verbal WM deficits in discriminators were correlated with auditory hallucinations but not with negative symptoms. The results are consistent with a verbal memory deficit in a subgroup of schizophrenia having intact auditory perception, which may stem from dysfunction of language-related cortical regions, and a more generalized cognitive deficit in a subgroup having auditory perceptual and attentional dysfunction.  相似文献   
870.
A traditional control group yoked to a group that self-controls their reception of feedback receives feedback in the same relative and absolute manner. This traditional control group typically does not learn the task as well as the self-control group. Although the groups are matched for the amount of feedback they receive, the information is provided on trials in which the individual may not request feedback if he or she were provided the opportunity. Similarly, individuals may not receive feedback on trials for which it would be a beneficial learning experience. Subsequently, the mismatch between the provision of feedback and the potential learning opportunity leads to a decrement in retention. The present study was designed to examine motor learning for a yoked group with the same absolute amount of feedback, but who could self-control when they received feedback. Increased mental processing of error detection and correction was expected for the participants in the yoked self-control group because of their choice to employ a limited resource in the form of a decreasing amount of feedback opportunities. Participants in the yoked with self-control group committed fewer errors than the self-control group in retention and the traditional yoked group in both the retention and time transfer blocks. The results suggest that the yoked with self-control group was able to produce efficient learning effects and can be a viable control group for further motor learning studies.  相似文献   
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