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261.
采用贝叶斯推理问题作为实验材料,探讨被试解决贝叶斯推理问题的启发式策略,从认知偏向的角度分析该问题的困难原因。结果发现:(1)贝叶斯推理问题解决过程中的可得性启发与后验概率估计过程中的直觉调整差误密切相关;(2)贝叶斯推理问题解决过程中文、理科被试都同样会产生直觉调整差误偏向;(3)贝叶斯推理问题解决过程中的后验概率估计值和对推理问题中包括虚报率信息的命题的可得性测量所得主观概率之间存在显著的负相关。 相似文献
262.
本文通过对426名在职人员的调查,探讨了变革型领导对工作绩效与满意度的影响机制。最后采用SPSS 13.0和Lisrel 8.7 对数据进行多层级线性回归分析,并依据温忠麟等(2006)的统计步骤分析了有中介的调节作用,得到如下结果:(1)在控制了年龄、性别与任职年限之后,自我效能在变革型领导与工作绩效、工作满意度之间都起部分中介作用;(2)核心工作特征在变革型领导与工作绩效之间起调节作用,调节作用需要通过自我效能作为中介变量。文章最后讨论了本研究的理论和实践意义。 相似文献
263.
摘要:通过流行病学测查,探讨不同亚型ADHD儿童的情绪、行为和社会功能的差异。采用SDQ(长处与困难问卷)对4500名7-10岁儿童进行大样本筛查,应用K-SADS-PL量表和DSM-Ⅳ诊断标准对其中263名高危儿童进行临床评估,诊断出119名儿童ADHD。诊断出的ADHD儿童中,男性与女性的比率大约为2.22︰1,存在显著的性别差异。混合型儿童ADHD的多动性不能得分显著高于注意缺陷性;混合型ADHD的社会功能得分显著低于注意缺陷型和多动型。7岁儿童ADHD的多动情况显著低于8岁、9岁。ADHD共病率为12.6%,ADHD儿童伴有学习困难的比例为43.2%。 相似文献
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Nanoscale Cu-rich precipitates (CRPs) are one of the most important microstructural nano-features responsible for embrittlement and hardening of reactor pressure vessels (RPVs), which threaten the safe operation of nuclear power plants (NPPs) and hinder the lifetime extension of nuclear reactors. A thermally aged Fe-1.1 wt.%Cu alloy, which is used to simulate embrittlement of the irradiated RPV steels, was treated by electropulsing with various parameters. The effect of electropulsing on nanoscale CRPs was investigated by using transmission electron microscopy (TEM). Compared to the traditional heat treatment, the electropulsing treatment (EPT) can accelerate the dissolution of CRPs in an aged Fe-Cu alloy on account of the higher atomic drift flux and the additional Gibbs free energy induced by electropulsing. More importantly, EPT is likely to be a new way of eliminating irradiation-induced Cu-rich precipitates. 相似文献
268.
Di Wu Kangcheng Wang Dongtao Wei Qunlin Chen Xue Du Junyi Yang Jiang Qiu 《Cognitive, affective & behavioral neuroscience》2017,17(1):211-223
In maladaptive respects, perfectionism reflects an individual’s concern over making mistakes and doubting the quality of his or her own actions excessively, which would affect one’s emotion. However, little is known about the neural mechanisms associated with the perfectionism and negative affect. In this study, voxel-based morphometry was performed to identify the brain regions underlying individual differences in perfectionism, which was measured by the Chinese Frost Multidimensional Perfectionism Scale (CFMPS), in a large sample of nonclinical young adults. Our results showed that the two subdimensions of the perfectionism, concern over mistakes (CM) and doubts about actions (DA), were both positively correlated with the self-reported anxiety and depression as well as the gray matter volume (GMV) in the anterior cingulate cortex (ACC), a pivotal brain region in cognitive control, affective state, and regulation. Moreover, CM, DA, and organization scores were respectively correlated with distributed brain regions involved in multiple cognitive and emotion processes. Our results furthermore revealed that the score of DA acted a mediational mechanism underlying the relationship between the GMV of ACC and self-rating negative affect (anxiety and depression). Taken together, these results might suggest the neuroanatomical basis of perfectionism and the association among the perfectionism, negative emotion, and brain architecture. This study emphasized that perfectionism could play a crucial role in the arousal of negative affect. 相似文献
269.
Ying Wei 《Journal of motor behavior》2017,49(4):422-428
The authors' purpose was to test the effect of asymmetric hand lifting on muscular activation patterns of 3 bilateral extensors. Eighteen male university students without back pain were volunteered. Each performed flexion–extension randomly with conditions of right lifting, left lifting, and nonlifting. Surface electromyography from bilateral thoracic, lumbar erector spinae, and hamstring was recorded. The cross-correlation and relative intensity in paired muscles of bilateral extensors was calculated in flexion as well as extension period. The results showed that the cross-correlation coefficient was decreased and the phase lag as well as the relative intensity of bilateral extensors was increased significantly in thoracic level. The phase lag as well as the relative intensity of bilateral extensors was increased significantly in lumbar level. It was concluded that asymmetric lifting has a significant effect on muscular activation of bilateral extensors in thorax level, which causes the ipsilateral extensor to activate larger and longer. Asymmetric lifting also has some effect on muscular activation of bilateral extensors in lumbar level but with less extent than in thorax level, which causes contralateral extensor to activate larger and longer. Asymmetric lifting seems to have no significant effect on muscular activation of bilateral hamstring. 相似文献
270.