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81.
Infants as young as 3 months of age can encode the relations among object features. Because object recognition depends critically upon a match between perceived feature configurations and representations of the object in long-term memory, the present experiments focused on infants' long-term memory for feature correlations. In 3 experiments with 72 3-month-olds, we documented the forgetting functions of different feature correlations, examined their relation to infants' memory for individual features, and replicated the findings with different stimuli. Infants were trained to activate a mobile composed of two kinds of blocks that differed in color, the figures displayed on them, and the figures' colors and were tested after different delays with recombinations of either the block colors, the figures, or the figure colors. Infants remembered some of the original feature combinations for up to 3 days but forgot all of them after 4 days. Even after 4 days, however, infants remembered the individual features that had entered into the original combinations. These results demonstrate that very young infants not only encode the relations among object features but also remember them for several days. Moreover, there is a dissociation in memory between features and feature relations: Feature relations are forgotten sooner than the individual features that comprise those relations.  相似文献   
82.
Swami Vivekananda, whose 150th birth anniversary is being celebrated this year, used to say, “This life is short; its vanities are transient. He alone lives who lives for others”. Norman Borlaug was one such person, who lived and worked for the cause of ensuring food for all. As a scientist, he helped to breed outstanding varieties of dwarf wheat, which could help to triple the average yield. As a humanist, he placed faces before figures, and helped to highlight the fact that the persistence of hunger, in the midst of opportunities to increase food production through synergy between technology and public policy, is inexcusable. Dr Borlaug was not satisfied with scientific know-how alone. He wanted to convert scientific know-how into field level do — how. On the last day of his life, a scientist showed him a new equipment to trace soil fertility. Dr Borlaug’s last words before his death were, “Take the tracer to the farmer”. On the occasion of his birth centenary on March 25, 2014 we should all follow his advice and accelerate progress in linking the lab with land. His life and work will be eternal sources of inspiration and lead us to convert his vision of a hunger-free world into reality. Borlaug’s Approach to Increasing Wheat Yield  相似文献   
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Nuclear fusion potentially offers a clean,environmentally friendly and intrinsically safe energy source with an abundant fuel supply.Magnetic fusion energy rese...  相似文献   
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  总被引:2,自引:0,他引:2  
Researchers often ask subjects to commit considerable time and effort to completing tasks that are not especially enjoyable. In a multistage investigation of sixth-grade boys and their families, we hypothesized that boys who were prone to high levels of distress (i.e., anxiety, depression, low self-esteem, and low well-being) but only low or moderate levels of self-restraint (i.e., consideration of others, impulse control, suppression of aggression, and responsibility) would be particularly unlikely to agree to participate. Consistent with this hypothesis, boys from 33 classrooms who were nominated by their peers as high in distress and moderate or low in self-restraint were significantly less likely than other boys to take part in an in-class survey. In addition, the families of boys who scored high in distress and moderate or low in self-restraint on the Weinberger Adjustment Inventory (WAI) were less likely than other families to agree to an observation session in their homes and to a series of telephone interviews about daily events in the boys' lives. Across the 3 phases of the research, the cumulative attrition rate of these at-risk boys was approximately 80%, compared to only 50% for those low in distress and/or high in self-restraint. These results suggest that the children of greatest interest in studies of social competence and family interaction may often be among those least adequately represented.  相似文献   
87.
Dutch boys 8 and 12 years old read brief stories about a harm doer whose intentions were either good or bad and whose actions resulted in either minor or serious injury to a victim. The harm doer had previously been either strongly provoked or not provoked by the victim. The older boys differentiated their evaluations of the harm doer's naughtiness on the basis of provocation and intentions, while the younger boys failed to differentiate their evaluations of the provoked harm doer on the basis of intentions. Both age groups strongly differentiated their judgments of the victim's naughtiness on the basis of his role as provoker, except when the victim was seriously injured by a bad-intentioned aggressor.  相似文献   
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  总被引:1,自引:0,他引:1  
OBJECTIVE: The purpose of the current study was to investigate the independent effects of different treatment elements on a number of secondary problems related to childhood and adolescent sexual abuse, as well as investigate a number of different moderators of treatment effectiveness. METHOD: Twenty-eight studies that provided treatment outcome results for children and adolescents who had been sexually abused were included in the meta-analysis. Different aspects of psychological treatment, such as specific treatment modalities (individual, cognitive-behavioral, etc.) or secondary problems (behavior problems, psychological distress, etc.) were investigated. RESULTS: The overall mean weighted effect size for the meta-analysis was d=.72 (SE=.02). The results indicate that psychological treatment after childhood or adolescent sexual abuse tended to result in better outcomes than no treatment. There was significant heterogeneity in the effectiveness of the various psychological treatment elements. Play therapy seemed to be the most effective treatment for social functioning, whereas cognitive-behavioral, abuse-specific, and supportive therapy in either group or individual formats was most effective for behavior problems. Cognitive-behavioral, family, and individual therapy seemed to be the most effective for psychological distress, and abuse-specific, cognitive-behavioral, and group therapy appeared to be the most effective for low self-concept. CONCLUSIONS: The choice of therapy modality should depend on the child's main presenting secondary problem. Further research should be conducted investigating other possible moderators and secondary problem outcomes.  相似文献   
90.
Results of the Vocabulary, Reading Comprehension, and Mathematics Concepts subtests for third-, sixth-, and eighth-grade students who took Form 5 of the Iowa Tests of Basic Skills in the 1976 school year were analyzed for sex bias. Statistical significance was found for each subtest for all of the grade levels. Follow-up analyses considered skill classification, sex-stereotypicalness, and item location of the items contributing to the statistical significance. No trends for these factors were found within each grade level for the four subtests considered. For all subtests, fewer items are identified at the third-grade level than for sixth or eighth grade, and these items, in general, favored boys. For the older students, when items are found to function differently for boys and girls, nearly half favor each sex. On the whole, little evidence for sex bias was found for the four subtests and three grade levels examined.  相似文献   
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