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71.
Conceptual systems theory asserts that abstract conceptual functioning must include a well-developed capacity to "act as if" and ability to assume the role of the other. This proposition was tested in two samples of adolescents with a person perception task that required subjects to give a target person's actual responses to Cattell's 16PF Test immediately after exposure to the target. Two videotaped targets were used. Conceptual level was found to influence accuracy as predicted in three of four analyses, and sex of subject as predicted in two of four, with the effects of intelligence controlled. Accuracy in the postdiction task, and four components of accuracy, were relatively stable across targets. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
73.
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
74.
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
75.
The citric acid fermentation by Aspergillus niger is divided into two consecutive phases, a growth phase when the cells proliferate but do not accumulate citrate, followed by an accumulating phase when they produce citrate but do not proliferate, or else do so at a much reduced rate. When studied in a low sucrose (0.4-0.8%) mpinimal salts medium the growth-accumulation alternative was controlled by the concentration of zinc: high zinc (about 1-2 muM) maintained growth phase, while at low zinc (below 1 muM) growth became limited by zinc deficiency and the cultures passed into accumulating phase. Addition of zinc to accumulating cultures resulted in their reversion to growth phase. Iron, manganese, calcium at concentrations as high as 5-10 muM had no influence on either growth or citrate accumulation. These results suggest that zinc plays a role in the regulation of growth and citric acid accumulation. 相似文献
76.
Two simple chromenes with anti-JH activity have been isolated and identified from the bedding plant Ageratum houstoianum. By contact and fumigation these compounds induce precocious metamorphosis and sterilization in several hemipteran species of insects. Certain holometabolous species are sterilized, forced into diapause, or both. Each of these biological actions is equivalent to removal of the corpora allata, which produce the JH's, and is reversible by treatment with exogenous JH. Thus, the action of these compounds is to stop the production or depress the titer of the JH's. To our knowledge, this is the first discovery of anti-JH, and we hope it will guide the way to the emergence of a fourth generation of safe and insect-specific pesticides. 相似文献
77.
78.
Microchip-based purification of DNA from biological samples 总被引:10,自引:0,他引:10
Breadmore MC Wolfe KA Arcibal IG Leung WK Dickson D Giordano BC Power ME Ferrance JP Feldman SH Norris PM Landers JP 《Analytical chemistry》2003,75(8):1880-1886
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
79.
McAllister Daniel J.; Kamdar Dishan; Morrison Elizabeth Wolfe; Turban Daniel B. 《Canadian Metallurgical Quarterly》2007,92(5):1200
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
80.
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