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81.
We evaluated the impact of RIPP-7, a seventh grade violence prevention curriculum designed to strengthen and extend the effects of the sixth grade RIPP-6 curriculum. Classes of seventh graders at two urban middle schools serving predominantly African-American youth where RIPP-6 had been implemented the preceding school year were randomized to intervention (N = 239) and control groups (N = 237). Compared to students in the control group, students who participated in RIPP-7 had fewer disciplinary code violations for violent offenses during the following school year. A limited number of main effects were found on self-report outcome measures and measures of attitudes. Although significant main effects were not found on self-report measures of physical aggression, drug use, or anxiety, analyses of interactions with pretest scores indicated that intervention effects were significantly moderated by pretest scores for several outcome measures. Students most likely to benefit from the intervention were those who reported higher pretest rates of problem behaviors including violent behavior, nonphysical aggression, and delinquent behavior.  相似文献   
82.
This article reviews map-learning and path-planning strategies within the context of map-based navigation in mobile robots. Concerning map-learning, it distinguishes metric maps from topological maps and describes procedures that help maintain the coherency of these maps. Concerning path-planning, it distinguishes continuous from discretized spaces and describes procedures applicable when the execution of a plan fails. It insists on the need for an integrated conception of such procedures, which must be tightly tailored to the specific robot that is used, notably to the capacities and limitations of its sensory-motor equipment, and to the specific environment that is experienced. A hierarchy of navigation strategies is outlined in the discussion, together with the sort of adaptive capacities each affords to cope with unexpected obstacles or dangers encountered on an animat or robot’s way to its goal.  相似文献   
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OBJECTIVE: Stress in pregnancy predicts earlier birth and lower birth weight. The authors investigated whether pregnancy-specific stress contributes uniquely to birth outcomes compared with general stress, and whether prenatal health behaviors explain this association. DESIGN: Three structured prenatal interviews (N = 279) assessing state anxiety, perceived stress, life events, pregnancy-specific stress, and health behaviors. MAIN OUTCOME MEASURES: Gestational age at delivery, birth weight, preterm delivery (<37 weeks), and low birth weight (<2,500 g). RESULTS: A latent pregnancy-specific stress factor predicted birth outcomes better than latent factors representing state anxiety, perceived stress, or life event stress, and than a latent factor constructed from all stress measures. Controlling for obstetric risk, pregnancy-specific stress was associated with smoking, caffeine consumption, and unhealthy eating, and inversely associated with healthy eating, vitamin use, exercise, and gestational age at delivery. Cigarette smoking predicted lower birth weight. Clinically-defined birth outcomes were predicted by cigarette smoking and pregnancy-specific stress. CONCLUSION: Pregnancy-specific stress contributed directly to preterm delivery and indirectly to low birth weight through its association with smoking. Pregnancy-specific stress may be a more powerful contributor to birth outcomes than general stress.  相似文献   
85.
Advice is a common but potentially problematic way to respond to someone who is distressed. Politeness theory (Brown & Levinson, 1987) suggests advice threatens a hearer's face and predicts that the speaker‐hearer relationship and the use of politeness strategies can mitigate face threat and enhance the effectiveness of advice messages. Students (N=384) read 1 of 16 hypothetical situations that varied in speaker power and closeness of the speaker‐hearer relationship. Students then read 1 of 48 advice messages representing different politeness strategies and rated the message for regard shown for face and for effectiveness. However, neither speaker‐hearer relationship nor politeness strategies was consistently associated with perceived threat to face or perceived advice effectiveness. We suggest revisions to politeness theory and additional factors that may affect judgments of face sensitivity and advice effectiveness.  相似文献   
86.
A two‐study investigation was designed to examine the role of job type (i.e. fit of political skill to work context) as a contextual moderator of the political skill–job performance relationship. Specifically, it was hypothesised that political skill operates most effectively in enterprising job contexts, and thus is most predictive of job performance in such contexts, but political skill would demonstrate no relationship with job performance in job contexts that did not emphasise interpersonal interaction and effectiveness. In Study 1, enterprising job demands interacted with political skill to affect job performance. That is, political skill positively and significantly predicted job performance in enterprising job contexts, as hypothesised. Study 2 selected one specific job context (i.e. insurance sales) high in enterprising job demands, and hypothesised that political skill would significantly predict objective measures of insurance sales (i.e. sales volume, performance‐based income, performance‐based commission rate, and performance‐based status). The results demonstrated significant predictive effects of political skill (i.e. beyond age, sex, education level, tenure on the job, and experience in sales) on all four measures of sales performance. Contributions and implications of this research, strengths and limitations, and directions for future study are discussed.  相似文献   
87.
This article addresses the impact of unification on East German families and on the situation of women in the East. The main hypothesis is that women are the losers of German unification, not only in terms of their decreasing participation in the labor force, but also in terms of their weakened position in partnerships and their increasing responsibilities in the domestic sphere. The findings are based primarily on personal interviews of different types of families. The first part of the article describes respondents' recollections of their everyday lives during the days of the former DDR (East Germany) and analyzes the specific family structures and relations between family members that prevailed. It focuses on the domestic division of labor and discusses the impact of high female employment on gender roles in the family and in the socialist society. The second part deals with the effects of German unification on families in East Germany.  相似文献   
88.
The demand that epistemic support be explicated as rational compulsion has consistently undermined the dialogue between theology and science. Rational compulsion entails too restrictive a form of epistemic support for most scientific theorizing, let alone interdisciplinary dialogue. This essay presents a less restrictive form of epistemic support, explicated not as rational compulsion but as explanatory power. Once this notion of epistemic support is developed, a genuinely productive interdisciplinary dialogue between theology and science becomes possible. This essay closes by sketching how the Big Bang model from cosmology and the Christian doctrine of Creation can be viewed as supporting each other.  相似文献   
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It is shown that, under very general conditions, uniqueness estimates proposed independently by Guttman [1957] and by Harris [1963] provide tighter upper bounds on the unknown uniqueness values of factor analysis than do existing estimates.The Illinois Department of Mental Health Drug Abuse Program is co-sponsored by the State of Illinois and the Department of Psychiatry, Division of the Biological Sciences and Pritzker School of Medicine, University of Chicago. Send reprint requests to Drug Abuse Programs—Research, East Pavilion, Museum of Science and Industry, 57th Street and South Lake Shore Drive, Chicago, Illinois 60637.  相似文献   
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