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Children between 7 and 8 years old took pan in a staged event at school and 1 week later were assessed using a short form of the Wechsler Intelligence scale for children (third edition) and measures of metamemory, narrative ability, and socioeconomic status. Two weeks following the event, children either received narrative elaboration training (NET; K.J. Saywitz & L. Snyder, 1996) and were prompted with the four NET cue cards at interview; received verbal prompts corresponding to the cue card categories, but without prior training; or were presented with the cards at interview without prior training. Children given verbal labels as prompts recalled as much information as children who received NET training and cue cards. Measures of intelligence were predictive of amount recalled for cards-only children but not for the other 2 groups, indicating that differences in recall between low- and high-IQ groups were attenuated when recall was supported by NET training or verbal prompting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Alzheimer's disease (AD) and Parkinson's disease (PD) impair working memory (WM). It is unclear, however, whether the deficits seen early in the course of these diseases are similar. To address this issue, the authors compared the performance of 22 patients with mild AD, 20 patients with early PD and without dementia, and 112 control participants on tests of inhibition, short-term memory, and 2 commonly administered tests of WM. The results suggest that although mild AD and early PD both impair WM, the deficits may be related to the interruption of different processes that contribute to WM performance. Early PD disrupted inhibitory processes, whereas mild AD did not. The WM deficits seen in patients with AD may be secondary to deficits in other cognitive capacities, including semantic memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study examined psychological and physiological stress, as well as muscle tension and musculoskeletal symptoms, among 72 female supermarket cashiers. Stress levels were found to be significantly elevated at work, as reflected in the catecholamines, blood pressure, heart rate, electromyographic (EMG) activity, and self-reports. Fifty cashiers (70%) suffering from neck-shoulder pain (trapezius myalgia) were found to have higher EMG activity at work and reported more tension after work. Women who kept a diary for 1 week and reported more musculoskeletal pain (above the median) were older, had higher blood pressure, and reported more work stress and psychosomatic symptoms. The elevated stress levels at work are consistent with data from workers involved in other types of repetitive tasks and can be important for the high prevalence of neck and shoulder symptoms among the cashiers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The linear polarization of light reflected from different cereal crops was studied to determine its potential to remotely detect differences in crop morphology. Photographs taken at intervals of 1–4 days, over a period of 11 weeks, were used to obtain polarization imagery of four cereal grain crops. The mean value of the linear polarization of light reflected from common wheat, barley, and durum wheat canopies decreased over a 15-day period during which the crops reached 50% heading. Over the succeeding 16-day period, the mean value of polarization showed a further decrease for the barley, but an increase for both the wheats due to lodging. These results indicate that linear polarization is a useful indicator of crop differences and crop maturity.  相似文献   
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Electromigrated nanogaps have shown great promise for use in molecular scale electronics. We have fabricated nanogaps on free-standing transparent SiN(x) membranes which permit the use of transmission electron microscopy (TEM) to image the gaps. The electrodes are formed by extending a recently developed controlled electromigration procedure and yield a nanogap with approximately 5 nm separation clear of any apparent debris. The gaps are stable, on the order of hours as measured by TEM, but over time (months) relax to about 20 nm separation determined by the surface energy of the Au electrodes. A major benefit of electromigrated nanogaps on SiN(x) membranes is that the junction pinches in away from residual metal left from the Au deposition which could act as a parasitic conductance path. This work has implications to the design of clean metallic electrodes for use in nanoscale devices where the precise geometry of the electrode is important.  相似文献   
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