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211.
Isabel Pavão Martins Martin Lauterbach Henrique Luís Helena Amaral Gail Rosenbaum Peter D. Slade 《Child neuropsychology》2013,19(5):466-478
Introduction and Aim: Neurological subtle signs (NSS) are often observed during the neurological examination of children and tend to disappear with age. Their persistence into late adolescence or young adulthood has been related to psychiatric and neurocognitive disorders. To provide a better understanding of their functional basis, a longitudinal correlational study with neurocognitive measurements was performed. Method: We conducted multiple regression and correlation analyses of NSS with demographic and cognitive measures on a subset of 341 healthy children (56% males), taking part in a longitudinal dental study. Participants, whose ages ranged between 11–15 years, at first evaluation, undertook yearly, during 5 years, a 6-item NSS exam (producing a total score ranging between 0–18) and a comprehensive battery of neurocognitive tests. Effects of age, gender, IQ, and 7 neurocognitive factors on NSS were analyzed. Results: Over the years, NSS scores correlated consistently with selective attention (Stroop test), motor speed (finger tapping), and visuomotor speed (pegboard speed). Discussion: These results suggest that the disappearance of NSS in late childhood and adolescence occurs primarily in parallel with the development of motor and visuomotor functions and secondarily in relation to higher order functions such as selective attention (Stroop) and executive control (B-A Trails difference). 相似文献
212.
We report an abnormally high residual dislocation density in aluminium in an Al/Ti/Al laminate annealed at 873 K for seven days. The residual dislocation density reaches 7.5 × 1014 m?2, higher than that in aluminum after severe plastic deformation processes such as accumulative roll bonding and high-pressure torsion. It is proposed that the high residual dislocation density may result from obstruction of the movement of TiAl3 nanoparticles by the grain boundary and Ti atoms conglomerating at vacancies distributed in the aluminium matrix at a high temperature for a sufficient time to allow a relatively stable crystal. 相似文献
213.
Guang-Hong Lu Akira Suzuki Akira Ito Masanori Kohyama Ryoichi Yamamoto 《Philosophical Magazine Letters》2013,93(11):757-766
The electronic properties of an Al = 9 tilt grain boundary with segregated Na and Ca impurity atoms have been calculated by a first-principles pseudopotential method. The results show that the boundary expands and the charge density decreases significantly over the whole boundary by the segregation of Na and Ca, and there are no stronger bonds than those associated with metallic bonding in the boundary even with the impurities. It is concluded that the embrittlement promotion mechanism by Na or Ca segregation in the Al boundaries is one kind of 'decohesion model'. 相似文献
214.
CeO2-doped diamond-like carbon (DLC) films with thicknesses of 180–200 nm were deposited by unbalanced magnetron sputtering. When the CeO2 concentration is in the range 5–8%, the residual compressive stress of the deposited films is reduced by 90%, e.g. from about 4.1 GPa to 0.5 GPa, whereas their adhesion strength increases. These effects are attributed to the dissolution of CeO2 within the DLC amorphous matrix and a widening interface between the DLC film and the Si substrate, respectively. 相似文献
215.
A multi-mode deformation model is used in a molecular dynamics simulation of nanocrystalline copper. Abundant deformation twin lamellae are developed by shearing the following compression to the elastic limit. Deformation twins (DTs) nucleate through two different mechanisms facilitated by Shockley partial slips. Interactions between DTs and Shockley partials are observed in this simulation. 相似文献
216.
Oi-ling Siu Chang-qin Lu Paul E. Spector 《European Journal of Work and Organizational Psychology》2013,22(5):520-531
This study examined the direct relationship between two social stressors (interpersonal conflict and organizational politics) and supervisor-rated job performance among employees in three Chinese societies in Greater China. The potential moderating effects of social support on the relation between social stressors and job performance were also investigated. Further, the potential mediating role of strain between stressors and job performance was tested. Data were collected from 1032 employees in Beijing, Hong Kong, and Taipei. The results showed that both types of social stressors were positively correlated with strain, and negatively related with job performance. There was evidence supporting that social support was a significant moderator of the social stressor–performance relationship. Further, results were consistent with the hypothesis that strain could be a mediator between social stressors and job performance. 相似文献
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218.
The present study extends the feedback-seeking behavior literature by investigating how supervisor-related antecedents (i.e., supervisors’ expert power, reflected appraisals of supervisors, and supervisors’ emotional intelligence) influence subordinates’ negative feedback-seeking behavior (NFSB) through different cost/value perceptions (i.e., expectancy value, self-presentation cost, and ego cost). Using data collected from 216 supervisor-subordinate dyads from various industries in Taiwan, we employ structural equation modeling analysis to test our hypotheses. The results show that expectancy value mediates the relationship between supervisor expert power and subordinates’ NFSB. Moreover, self-presentation cost mediates the relationship between reflected appraisals of supervisors’ and subordinates’ NFSB. Theoretical and practical implications of this study are also discussed. 相似文献
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220.
本文对择偶与人类嗓音之间的关系进行了深入分析。首先, 人类具有普遍的异性嗓音偏好:男性偏爱高音调的女性嗓音, 女性偏爱低音调的男性嗓音, 这种普遍偏好受到一系列跟自身婚配价值有关的因素的调节。其次, 人类的嗓音偏好跟嗓音背后的进化意义密切关联:女性化嗓音是女性生育力的线索, 而男性化嗓音是男性好基因和好资源的线索。而且, 富有吸引力的男性嗓音和女性嗓音能够预测个体的性行为和繁殖成功。再次, 富有有吸引力的人类嗓音影响个体的社会认知, 对亲密关系的维系也会带来消极影响。最后, 我们探讨了未来研究的若干方向:研究基频之外的其他嗓音参数, 探讨嗓音偏好的性选择机制、特殊群体的嗓音偏好, 以及嗓音偏好与其他认知过程的关系。 相似文献