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991.
Abstract

The local translational order of the icosahedral quasicrystalline phase in rapidly solidified V41Ni36Si23 has been investigated by means of selected-area electron diffraction and high-resolution electron microscopy. Experimental results show that translational order always occurs in the twofold direction and can be observed when the quasicrystal is examined along its fivefold and threefold as well as twofold axes. Sometimes it occurs in two or three coplanar twofold directions simultaneously. In these cases some crystalline islands exist in the icosahedral quasicrystal and this corresponds to the initial stage of transformation from a quasicrystal to the stable crystalline phase.  相似文献   
992.
993.
994.
Organizations often utilize empowerment as a way to bolster performance. It is largely assumed, however, that its impact in this capacity is equivalent across organizational members. We tested this notion within a sample of 420 employees belonging to 75 teams in a Chinese organization and found that team empowerment related positively to supervisor‐rated in‐role and self‐rated extra‐role performance through its effect on individual psychological empowerment. More important, employee–coworker demographic dissimilarity moderated both stages of this indirect relationship. Specifically, when employee–coworker sex dissimilarity was higher, the following relationships were attenuated: (a) team empowerment–individual empowerment, (b) individual empowerment–in‐role performance, and (c) individual empowerment–extra–role performance. Collectively, the results illustrate that the impact of empowerment is contingent upon demographic dissimilarity.  相似文献   
995.
We propose a hierarchical Bayesian model for analyzing multi-site experimental fMRI studies. Our method takes the hierarchical structure of the data (subjects are nested within sites, and there are multiple observations per subject) into account and allows for modeling between-site variation. Using posterior predictive model checking and model selection based on the deviance information criterion (DIC), we show that our model provides a good fit to the observed data by sharing information across the sites. We also propose a simple approach for evaluating the efficacy of the multi-site experiment by comparing the results to those that would be expected in hypothetical single-site experiments with the same sample size.  相似文献   
996.
本研究采用纵向设计,对170名儿童(实验组:101人;对照组:69人)进行为期两学年的追踪,旨在探讨书法练习对儿童情绪状态及认知性情绪调节策略发展的影响。研究发现,1)以前测成绩为协变量,后测时实验组的积极情绪显著高于对照组;2)实验组在“积极重新关注”、“计划”两维度上的情绪调节策略得分增量(后测-前测)显著高于对照组。结果表明,书法练习对儿童情绪及其调节策略发展具有促进作用。  相似文献   
997.
在匹配了情绪刺激的效价和唤醒度后,检验了情绪的动机程度对注意范围的影响。研究采用Navon字母任务,通过被试对整体字母和局部字母的反应考察了注意范围的变化。结果显示,被试在中性状态下出现整体加工偏向;在低动机程度的正性和负性情绪下偏向加强,注意范围扩大;在高动机程度的正性和负性情绪下偏向减弱,注意范围缩小。因此,在同一效价内动机程度的不同仍会影响注意加工,高动机程度窄化注意范围,低动机程度反之。  相似文献   
998.
In daily life, people frequently need to observe dynamic objects and temporarily maintain their representations in visual working memory (VWM). The present study explored the mechanism underlying the binding between perceptual features and locations of dynamic objects in VWM. In three experiments, we measured and compared the memory performance for feature-location binding of multiple dynamic and static objects. The results showed that the feature-location binding was impaired for the dynamic objects compared with the static objects. The impairment persisted when the global spatial configuration of the objects remained intact during the motion, as well as when the binding task was relatively easy, such as binding between single-feature objects and coarse locations. The results indicate that object features and locations are not maintained in VWM as well-integrated object files; rather, the formation of feature-location binding may require additional processes, which are disrupted by the constant change of locations in dynamic circumstances. We propose a consolidation process as possible underlying mechanism, and discuss factors that may influence the strength of feature-location binding in dynamic circumstances.  相似文献   
999.
Unsociable children are likely to develop adjustment difficulties in Chinese society. The primary goal of the present study was to examine the moderating effect of behavioural control on the relation between unsociability and peer problems in Chinese children. Participants were fourth to eighth grade students in urban China (N = 787). Assessments of unsociability, shyness, peer problems and behavioural control were obtained from peer nominations and teacher ratings. Results indicated that unsociability was positively related to peer problems in Chinese children after controlling for shyness. Also, the relation between unsociability and peer problems was attenuated among children with higher behavioural control. Thus, behavioural control may be a buffering factor that serves to protect unsociable children from developing peer problems. Gender and age also moderated these associations. Results are discussed in terms of the meaning and implications of unsociability and behavioural control in Chinese culture. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
1000.
Caregiver mental health is widely considered to be an important factor influencing children's asthma symptoms. The present study aimed to examine key factors that contribute to caregiver mental health in pediatric asthma with a Chinese sample. Two hundred participants reported their family socioeconomic status (SES), proneness to shame, asthma symptoms control of their child, family functioning, and their depression and anxiety symptoms. Results suggested that low family SES, low family functioning, and a high level of shame proneness were associated with high levels of anxiety and depression for caregivers. Family functioning mediated the effects of SES and shame on caregiver mental health and also moderated the effects of SES and shame on caregiver depression. This study highlights the importance of reducing experience of shame and enhancing family functioning in families affected by pediatric asthma.  相似文献   
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