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471.
472.
The temperature dependence of the elastic moduli was estimated from ultrasound time of flight measurements performed on bulk metallic glasses of composition Zr63? x Cu24Al x Ni10Co3. Using the corresponding values at the glass transition temperature, the local atomic strain was determined. The obtained values for the critical atomic strain calculated for 8 at%?<?x?<?15 at% are close to the predicted universal criterion derived from a topological model, but may also reflect the difference in the chemical interaction that are not accounted by a topological approach.  相似文献   
473.
Members of Troops to Teachers (N = 102 male veterans) were surveyed regarding their career transition experiences and life satisfaction. Primary themes related to career transition included preparation for transition, investment vs. sacrifice, and rewards of new career. Primary themes related to life satisfaction included helping and serving others, accomplishment, and contentment vs. struggle.  相似文献   
474.
ABSTRACT

The directed forgetting effect obtained with the item method is supposed to depend on both selective rehearsal of to-be-remembered (TBR) items and attentional inhibition of to-be-forgotten (TBF) items. In this study, we investigated the locus of the directed forgetting deficit in older adults by exploring the influence of recollection and familiarity-based retrieval processes on age-related differences in directed forgetting. Moreover, we explored the influence of processing speed, short-term memory capacity, thought suppression tendencies, and sensitivity to proactive interference on performance. The results indicated that older adults' directed forgetting difficulties are due to decreased recollection of TBR items, associated with increased automatic retrieval of TBF items. Moreover, processing speed and proactive interference appeared to be responsible for the decreased recall of TBR items.  相似文献   
475.
One way to improve safety under reduced visibility conditions (i.e., reduce the chances of visibility related crashes) is to improve drivers’ behavior under such adverse weather conditions. The aim of this paper is to thoroughly examine drivers’ responses under low visibility conditions and quantify the impacts and values of various factors found to be related to drivers’ compliance and drivers’ satisfaction with variable speed limit (VSL) and changeable message signs (CMS) instructions in different visibility, traffic conditions, and on two types of roadways; freeways and two-lane roads.The data used for the analyses were obtained from a self-reported questionnaire survey carried out among 566 drivers in Central Florida, USA. To achieve these goals, Explanatory Factor Analysis (EFA) and Structural Equation Modeling (SEM) approaches were adopted.The results revealed that drivers’ satisfaction with VSL/CMS was the most significant factor that positively affected drivers’ compliance with advice or warning messages displayed on VSL/CMS under different fog conditions followed by human factors. Moreover, it was found that roadway type affected drivers’ compliance to VSL instructions under medium and heavy fog conditions. Furthermore, drivers’ familiarity with VSL and human factors were the significant factors affecting drivers’ satisfaction with VSL/CMS advice under reduced visibility conditions. Based on the findings of the present study, several recommendations are suggested as guidelines to improve drivers’ behavior in such reduced visibility conditions by enhancing drivers’ compliance with VSL/CMS instructions.  相似文献   
476.
The idea that information processing speed is related to cognitive ability has a long history. Much evidence has been amassed in its support, with respect to both individual differences in general intelligence and developmental trajectories. Two so-called elementary cognitive tasks, reaction time and inspection time, have been used to compile this evidence, but most studies have used either one or the other. Relations between speed and fluid intelligence have tended to be stronger than those between speed and crystallized intelligence, but studies testing this have confounded verbal abilities with crystallized intelligence and spatial/perceptual abilities with fluid intelligence. Questions have also been raised regarding whether speed contributes directly to general intelligence or to more specific cognitive abilities to which general intelligence also contributes. We used 18 ability and speed measures in the Lothian Birth Cohort 1936, assessed at approximately age 70, to construct alternative versions of the Verbal-Perceptual-Image Rotation (Johnson & Bouchard, 2005a) model of cognitive ability to test different hypotheses regarding these issues. Though differences in the extents to which our models fit the data were relatively small, they suggested that reaction and inspection time tasks were comparable indicators of information processing speed with respect to general intelligence, that verbal and spatial abilities were similarly related to information processing speed, and that spatial, verbal, and perceptual speed abilities were more directly related to information processing speed than was general intelligence. We discuss the theoretical implications of these results.  相似文献   
477.
使用EyeLink2000眼动仪,以30名大学生为被试,采用3(窗口大小:5字、10、15字)×2(呈现速度:300字/分、600字/分)×3(字号:24号、36号、48号)多因素混合设计,考察了窗口大小、呈现速度和字号对引导式文本阅读的影响。结果表明:(1)字号的主效应显著,字号越大,越有利于阅读;(2)呈现速度的主效应显著,慢速更有利于阅读;(3)呈现速度和字号的交互作用显著,慢速和中号、慢速和大号更有利于阅读。  相似文献   
478.
This study evaluated multiple constraints of verbal working memory in typically developing 7- to 11-year-olds. Multiple measures of verbal working memory and the predictors-short-term memory storage, general speed, and domain-general controlled attention were used. General linear modeling (GLM) showed that storage and the efficiency of controlled attention (i.e., speed of updating information during attention switching) contributed to significant variance in children's verbal working memory. In a secondary analysis verbal storage and domain-general attention (focus switching accuracy and speed of updating on switch) emerged as significant predictors. Results suggest domain-general attention and verbal storage mechanisms to be independent constraints of verbal working memory.  相似文献   
479.
Schizophrenia is characterized by heterogeneous brain abnormalities involving cerebral regions implied in the executive functioning. The dysexecutive syndrome is one of the most prominent and functionally cognitive features of schizophrenia. Nevertheless, it is not clear to what extend executive deficits are heterogeneous in schizophrenia patients. Furthermore, it is still unknown if the executive impairments observed in schizophrenia are better characterized as specific or as reflecting generalized cognitive factors. The four executive processes (i.e. updating, inhibition, shifting and divided attention) described in Miyake et al.'s (2000) theoretical model were examined in 62 individuals with schizophrenia and 49 healthy controls. At group level, impairments in all four executive processes confirmed the marked impairment in executive functioning in patients with schizophrenia. Statistical analysis indicated that executive performances in schizophrenia patients were more heterogeneous than in healthy controls. Compared with standardized norms, 94% of patients exhibited impairment in at least one of the executive tasks. Twenty-one percent of patients exhibited impairment in one executive task, 27% in two tasks, 23% in three executive tasks and 23% exhibited impairments in the four executive tasks. Six percent of patients had normal executive profile. Regression analysis indicated that only premorbid intellectual quotient and a general slowing in processing speed predicted the executive dysfunction severity. Executive functioning was not affected by age, duration of illness, psychotic status, or by antipsychotic dosage. Our results emphasize the heterogeneity of the dysexecutive syndrome in schizophrenia when individual profile analysis is considered, and extend the view that individual cognitive differences in schizophrenia are largely underlined by general cognitive factors such as intellectual level and general processing speed.  相似文献   
480.
The processing-speedtheory and the prefrontal-executivetheory are competing theories of cognitive aging. Here we used a theoretically and methodologically-driven framework to investigate the relationships among measures classically used to assess these two theoretical constructs. Twenty-eight young adults (18-32 years) and 39 healthy older adults (65-80 years) performed a battery of nine neuropsychological and experimental tasks assessing three executive function (EF) components: Inhibition, Updating, and Shifting. Rate of information processing was evaluated via three different experimental and psychometric tests. Partial correlations analyses suggested that 2-Choice Reaction Time (CRT) performance is a more pure measure of processing speed than Digit Symbol Substitution Test (DSST) performance in the elderly. Hierarchical regression analyses showed that, although measures of processing speed and EF components share mutual variance, each measure was independently affected by chronological age. The unique adverse effect of age was more important for processing speed than for EF. The processing-speed theory and the prefrontal-executive theory of cognitive aging were shown not to be mutually exclusive but share mutual variance. This implies the need to control for their mutual relationship before examining their unique potential role in the explanation of age-related cognitive declines. Caution has still to be taken concerning the tasks used to evaluate these theoretical constructs.  相似文献   
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