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241.
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   
242.
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   
243.

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   
244.
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   
245.
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   
246.
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   
247.
采用模拟投资任务和问卷测查的方式,考察了投资者的风险感知、风险倾向对其风险决策的影响,并对风险感知与风险倾向的交互作用进行分析。结果发现:①投资者的风险感知对其风险决策有显著的负向作用;②投资者的风险倾向对其风险决策有显著的正向作用;③风险感知对风险决策的影响作用部分通过风险倾向这一中介完成。  相似文献   
248.
周岚 《应用心理学》2013,(4):317-323
基于概念整合理论和范畴化原型理论,以对真实语料的统计分析结果为4P-据,探讨了中国英语学习者在1:2语表达过程中的英语单数第三人称代词(ETPSP)误用现象及其原因,结果表明:(1)中国大学生存在普遍的ETPSP误用现象,主要表现为主语he/she、宾语him/her和定语his/her三类间的误用,特别是主语he/she间的误用人数比例高达75%;(2)英语学习水平对ETPSP误用具有重要影响,且主要表现为低水平组对“she”产出的高错误率,主要原因是其对“he(she)”产出错误的认知实时监控能力缺乏。  相似文献   
249.
This study has established a relationship model encompassing such aspects as consumer values, consumer involvement, purchase behavior, and consumer satisfaction. Furthermore, taking counterfeit goods as an example, this study employs factor analysis, reliability analysis, and the structural equation model to verify the relationship between the research aspects. Another major discovery of this study was that teenagers' behavioral purchasing mentality is graphic, hyperlinked, and is geared toward useful situations and functional needs. When they consider their degree of need, they inevitably incorporate many emotional needs. However, their attitude toward counterfeit goods is rational, which is confirmed by the fact that Hypothesis 1 was not supported.  相似文献   
250.
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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