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181.
We report that <c+a> pyramidal slipping could be more easily activated in textured Mg–Ca alloys with increasing Ca contents dissolved in α-Mg matrix under tensile deformation, and it is proposed that the decreased stacking fault energy plays the critical rule. In contrast, only twins and <a> basal dislocations are observed in the compressed samples. The results would provide insight into understanding of the deformation mechanism and designing more ductile Mg alloys.  相似文献   
182.
Complex-span (working-memory-capacity) tasks are among the most successful predictors of intelligence. One important contributor to this relationship is the ability to efficiently employ cues for the retrieval from secondary memory. Presumably, intelligent individuals can considerably restrict their memory search sets by using such cues and can thereby improve recall performance. We here test this assumption by experimentally manipulating the validity of retrieval cues. When memoranda are drawn from the same semantic category on two successive trials of a verbal complex-span task, the category is a very strong retrieval cue on its first occurrence (strong-cue trial) but loses some of its validity on its second occurrence (weak-cue trial). If intelligent individuals make better use of semantic categories as retrieval cues, their recall accuracy suffers more from this loss of cue validity. Accordingly, our results show that less variance in intelligence is explained by recall accuracy on weak-cue compared with strong-cue trials.  相似文献   
183.
In the current study, we examined the developmental course of the perception of non‐native tonal contrast. We tested 4, 6 and 12‐month‐old Dutch infants on their discrimination of Chinese low‐rising tone and low‐dipping tone using the visual fixation paradigm. The infants were tested in two conditions that differed in terms of degree of variability. The 4‐month‐olds did not show discrimination effect in either condition. The 6‐ and 12‐month‐old infants, however, discriminated the tones in both conditions. The improvement of perception might be the result of cognitive development carried over from learning the native phonology. Infants can become better listeners in general in the first year of life, as well as get cognitively better equipped in dealing with the variable input in speech in general. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In children, intense levels of anxiety during anesthetic induction are associated with a higher risk of pain, poor recovery, and emergence delirium. Therefore, it is important to identify these high-risk children at hospital arrival. The current study examined internalizing behavior (Child Behavior Checklist, CBCL) and state anxiety measures (modified Yale Preoperative Anxiety Scale, mYPAS, and State Trait Anxiety Inventory for Children, STAIC) at hospital arrival as predictors of anxiety during induction of anesthesia. One hundred children (aged 4 to 12 years) undergoing elective daycare surgery were included. The STAIC and mYPAS at hospital arrival were significant predictors of anxiety during induction, whereas CBCL was not. The STAIC state form at hospital arrival was the strongest predictor and could be used to identify children who will experience intense levels of anxiety during anesthetic induction, with sufficient to good diagnostic accuracy. Using the STAIC at hospital arrival allows targeted interventions to reduce anxiety in children.

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智能平衡评估系统是美国目前使用最为广泛的教育评估系统之一。该系统的三大部分——总结性评估系统、中期评估系统和数字图书馆构成一个畅通的教学、反馈、助教与助学的教育循环系统。我国可借鉴智能平衡评估系统的思想和所采用的技术,将相对独立的教育督导、教育研究、考试命题、学校等事业机构在功能上联合起来形成完整的教育链,建构日常教学评估系统,从而提高国内教育的效益,减轻教与学的负担。  相似文献   
188.
基于迁移适当加工理论,采用连续识别任务范式,通过操纵字词和图片的模糊度来考察知觉模糊非流畅的延迟效应。结果发现:(1)模糊不流畅的材料学习判断值更低;(2) 知觉模糊程度对即时的再认成绩没有影响,但在延迟再认测试中流畅性较低的模糊材料成绩更好。该结果表明实验操纵方式所引发的编码过程和记忆测试所需的检索过程性质上相匹配,而且延迟测试时,知觉非流畅可以促进学习,说明该效应存在边界。  相似文献   
189.
Both parents and offspring have evolved mating preferences that enable them to select mates and children-in-law to maximize their inclusive fitness. The theory of parent–offspring conflict predicts that preferences for potential mates may differ between parents and offspring: individuals are expected to value biological quality more in their own mates than in their offspring's mates and to value investment potential more in their offspring's mates than in their own mates. We tested this hypothesis in China using a naturalistic ‘marriage market’ where parents actively search for marital partners for their offspring. Parents gather at a public park to advertise the characteristics of their adult children, looking for a potential son or daughter-in-law. We presented 589 parents and young adults from the city of Kunming (Yunnan, China) with hypothetical mating candidates varying in their levels of income (proxy for investment potential) and physical attractiveness (proxy for biological quality). We found some evidence of a parent–offspring conflict over mate choice, but only in the case of daughters, who evaluated physical attractiveness as more important than parents. We also found an effect of the mating candidate's sex, as physical attractiveness was deemed more valuable in a female potential mate by parents and offspring alike.  相似文献   
190.
Recent research suggests that one of the mechanisms that contribute to infants' acquisition of their physical knowledge is the formation of event categories, such as occlusion and containment. Some of this research compared infants' identification of similar variables in different event categories. Marked developmental lags were found, suggesting that infants acquire event-specific rather than event-general expectations. Other research - on variable priming, perseveration, and object individuation - presented infants with successive events from the same or from different event categories. To understand the world as it unfolds, infants must not only represent each separate event, but also link successive events; this research begins to explore how infants respond to multiple events over time.  相似文献   
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