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31.
Investigated the problem behaviors of 35 physically abused 6–16 yr olds in comparison with 36 nonabused children from a child welfare agency and 35 nonabused children in the community. Parental report of behavioral strengths and weaknesses was examined by administering the Child Behavior Profile. Results concur with those of previous reports that abused children display a significantly greater number of behavior problems and fewer social competencies than normals. The behavior patterns of abused Ss closely resembled the range of behavior problems shown by Ss from distressed families in which abuse was not present. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The ALS–a portable, retargetable, integrated environment–is being designed to meet rigorous Stoneman requirements. It addresses critical development and maintenance problems of embedded computer systems.  相似文献   
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Microchip-based purification of DNA from biological samples   总被引:10,自引:0,他引:10  
A microchip solid-phase extraction method for purification of DNA from biological samples, such as blood, is demonstrated. Silica beads were packed into glass microchips and the beads immobilized with sol-gel to provide a stable and reproducible solid phase onto which DNA could be adsorbed. Optimization of the DNA loading conditions established a higher DNA recovery at pH 6.1 than 7.6. This lower pH also allowed for the flow rate to be increased, resulting in a decrease in extraction time from 25 min to less than 15 min. Using this procedure, template genomic DNA from human whole blood was purified on the microchip platform with the only sample preparation being mixing of the blood with load buffer prior to loading on the microchip device. Comparison between the microchip SPE (microchipSPE) procedure and a commercial microcentrifuge method showed comparable amounts of PCR-amplifiable DNA could be isolated from cultures of Salmonella typhimurium. The greatest potential of the microchipSPE device was illustrated by purifying DNA from spores from the vaccine strain of Bacillus anthracis, where eventual integration of SPE, PCR, and separation on a single microdevice could potentially enable complete detection of the infectious agent in less than 30 min.  相似文献   
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The objective of this study was to empirically disentangle role perceptions related to organizational citizenship behavior (OCB) that have been confounded in past research, investigate their unique relationships with both an affiliative (helping) and a challenging (taking charge) form of OCB, and determine their relative importance in explaining these 2 forms of OCB. The authors also examined whether role discretion and role breadth independently moderate the procedural justice-to-OCB relationship. The authors surveyed 225 engineers in India and their direct supervisors. The results showed that 3 of the 4 facets of OCB role perception explain unique variance in either helping or taking charge, and that role breadth moderates the relationships between procedural justice and both helping and taking charge. The authors discuss implications of these findings for OCB theory and research, as well as for managerial practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
Genetic algorithms are a technique for search and optimization based on the Darwinian principle of natural selection. They are iterative search procedures that maintain a population of candidate solutions. The best or most fit solutions in that population are then used as the basis for the next generation of solutions. The next generation is formed using the genetic operators reproduction, crossover, and mutation. Genetic algorithms have been successfully applied to engineering search and optimization problems. This paper presents a discussion of the basic theory of genetic algorithms and presents a genetic algorithm solution of a lumber cutting optimization problem. Dimensional lumber is assigned a grade that represents its physical properties. A grade is assigned to every board segment of a specific length. The board is then cut in various locations in order to maximize its value, A genetic algorithm was used to determine the cutting patterns that would maximize the board value.  相似文献   
36.
Research on self-esteem has focused almost exclusively on level of trait self-esteem to the neglect of other potentially more important aspects such as the contingencies on which self-esteem is based. Over a century ago, W. James (1890) argued that self-esteem rises and falls around its typical level in response to successes and failures in domains on which one has staked self-worth. We present a model of global self-esteem that builds on James' insights and emphasizes contingencies of self-worth. This model can help to (a) point the way to understanding how self-esteem is implicated in affect, cognition, and self-regulation of behavior, (b) suggest how and when self-esteem is implicated in social problems; (c) resolve debates about the nature and functioning of self-esteem; (d) resolve paradoxes in related literatures, such as why people who are stigmatized do not necessarily have low self-esteem and why self-esteem does not decline with age; and (e) suggest how self-esteem is causally related to depression. In addition, this perspective raises questions about how contingencies of self-worth are acquired and how they change, whether they are primarily a resource or a vulnerability, and whether some people have noncontingent self-esteem. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Study 1, with 386 undergraduates, demonstrated that the Concern for Appropriateness Scale and the Revised Self-Monitoring Scale (SMS—R) developed by the 1st 2 authors (see record 1984-27678-001) were orthogonal and that they were predictably related to measures of self-esteem, social anxiety, shyness, and sociability. Study 2, with an additional 249 Ss, showed that Ss high in concern for appropriateness tended to describe their own drug use as due to inducement by others, whereas Ss who scored high on the SMS—R tended to describe their drug use as self-initiated. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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