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931.
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933.
BOOK REVIEWS     
The Politics of Education in the Local Community. Robert S. Cahill and Stephen P. Hencley, Editors.
The Political Power and Educational Decision-Making. By Ralph B. Kimbrough.  相似文献   
934.
Cohn and Farrington’s work in citation analysis has examined scholarly influence within criminological research for over 25 years. The current analysis tracks the ten most-cited scholars and each scholar’s most-cited works in four international criminology journals and six American criminology and criminal justice journals over twenty-five years and five time periods—1986–1990, 1991–1995, 1996–2000, 2001–2005, and 2006–2010. This approach extends the traditional approach to citation analysis by documenting increases and decreases in individual citation careers as well as in the most-cited scholarly contributions of the most-cited scholars during a period of significant growth in criminology. The most-cited works mostly fall within the areas of developmental and life-course criminology and criminal careers, reflecting the importance of these topics in criminology.  相似文献   
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OBJECTIVE: To examine the relationship between parental history of substances use disorders (SUDs) and abuse potential. METHOD: Milner's (1986) Child Abuse Potential Inventory (CAPI) was administered to fathers and mothers (with and without histories of SUDs) of 10- to 12-year-old boys. RESULTS: Fathers and mothers with lifetime histories of SUDs had higher Abuse Scale scores and were more likely to score in the Elevated range (as determined by clinically significant cutoff scores) than parents without such histories. No differences were found between parents with current diagnoses of SUD and those with past (but not current) histories of SUD. Fathers and mothers with a partner who had a history of SUD were more likely to score in the Elevated range, regardless of their own SUD histories. Separate regression models revealed that, for both fathers and mothers, emotional dysregulation (positive and negative affectivity) predicted Abuse Scale scores. Additional contributors to Abuse Scale scores were SUD status in fathers, and lack of involvement with the child in mothers. CONCLUSIONS: History of SUDs in both fathers and mothers increases abuse potential. Contributors to abuse potential differed in fathers and mothers, underscoring the importance of examining parents separately in child maltreatment research.  相似文献   
937.
In each of two experiments, rats were trained to press the lever in a Skinner box, food reinforcement being available on a variable-interval 60-sec schedule (VI 60). There followed an “exposure phase” for which the levers were removed from the boxes, and then a final test with the levers replaced to assess the effects of the intervening treatment on instrumental responding. Experiment 1 showed that simple exposure to the box reduced the vigor of instrumental performance in comparison with a condition in which food was made available during the exposure phase. Animals which received no exposure treatment also showed a relatively high rate of response. Experiment 2 demonstrated that an exposure treatment in which the occurrence of food is signaled by a light stimulus also leads to a decline in instrumental responding. These results are held to support the notion that associations between the context and the reinforcer serve to energize appetitive instrumental behavior.  相似文献   
938.
Analysis of self-reflections of undergraduate education students in a project involving web-supported counterintuitive science demonstrations is reported in this paper. Participating students (N?=?19) taught science with counterintuitive demonstrations in local elementary school classrooms and used web-based resources accessed via wireless USB adapters. Student reflections to seven questions were analyzed qualitatively using four components of reflection (meeting objectives/perception of learning, dynamics of pedagogy, special needs accommodations, improving teaching) deriving 27 initial data categories and 12 emergent themes. Overall the undergraduates reported meeting objectives, engaging students in pedagogically relevant learning tasks including, providing accommodations to students with special needs, and gaining practice and insight to improve their own teaching. Additional research is needed to arrive at generalizable findings concerning teaching with web-supported counterintuitive science demonstrations in elementary classrooms.  相似文献   
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940.
Based on the momentum conservation approach, a theoretical model was developed to predict the superficial liquid velocity, and a correlation equation was established to calculate the gas holdup of an annular external- loop airlift reactor(AELAR)in the bubble flow and developing slug flow pattern. Experiments were performed by using tap-water and silicone oil with the viscosity of 2.0 mm2/s(2cs-SiO)and 5.0 mm2/s(5cs-SiO)as liquid phases. The effects of liquid viscosity and flow pattern on the AELAR performance were investigated. The predictions of the proposed model were in good agreement with the experimental results of the AELAR. In addition, the comparison of the experimental results shows that the proposed model has good accuracy and could be used to predict the gas holdup and liquid velocity of an AELAR operating in bubble and developing flow pattern.  相似文献   
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