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31.
Qualitative performance features and extended-time effects on the Block Design subtest of the Wechsler Adult Intelligence Scale—Revised (WAIS—R) were examined in 145 healthy Ss (aged 50–95 yrs). Raw scores were calculated at standard and extended time limits; error types and starting points were recorded for a subgroup of Ss. In Ss age 60 yrs and older, there was a consistent decline with age in overall scores at both time limits. Extra time allotments resulted in modest but significant increases in scores. Older and younger Ss benefited equally from the extra time, indicating that the age-related decline on this task cannot be accounted for by general age-related psychomotor slowing. Single- and multiblock rotation errors were relatively common, whereas stimulus boundedness and broken configurations were rare. Despite some potential limitations in generalizability, the results suggest that the incorporation of qualitative scoring procedures in the assessment of visuoconstructional skills may enhance understanding of normal and abnormal brain–behavior relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Examined the emotional similarity hypothesis, a derivation from social comparison theory, which predicts that increasing fear should lead to greater affiliation with someone who is awaiting the same threat (and who therefore is of relatively similar emotional status) relative to someone who has already experienced the threat (and who therefore is of relatively dissimilar emotional status). Results failed to support the emotional similarity hypothesis and in so doing challenged the importance of emotional comparison as a determinant of verbal affiliation under threat. Cognitive clarity concerns instead seemed to account better for the observed effects on verbal affiliation. Supplementary analyses of nonverbal affiliation (facial glances) likewise ran counter to an emotional similarity prediction. Effects of affiliation on anxiety were also examined. Previous conclusions regarding the pattern and causes of affiliation under threat that have relied on the affiliate-choice paradigm are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
33.
A method to measure short-crack R -curves is introduced which does not require an independent determination of calibration factors and which utilizes an equilibrium crack shape condition to compute the shape factor of a surface crack, R -curves of an alumina with two different grain sizes and of an aluminum/alumina composite were measured in the crack length regime of below 100 μm up to almost 1000 μm. Calculated and experimentally obtained crack depth profiles were in good agreement with deviations being between −22% and +26% for the crack ellipticity and confirmed the reliability of the method.  相似文献   
34.
The ab-initio crystal structure solution by powder diffraction data requires great efforts because of the collapse of the experimental information onto the one dimensional 2θ axis of the pattern. Different strategies will be described aiming at improving the process of extraction of the integrated intensities from the experimental pattern in order to make more straightforward the structure solution process by direct methods. Particular attention will be devoted to the EXPO program. Some of its performance will be analysed and results will be shown.  相似文献   
35.
Imageability of places, cities and countries is strongly influenced by tourist and political portraits in the media. As human cognition relies on inferential perception and contrasting categories, marketing strategies exploit partial truths and conflicting city images to direct public perceptions. This article addresses the relationship between international perception, image building and urban design in the case of Brazil and the cities of Rio de Janeiro and Curitiba. Their contrasting images as exploited by the international media expose only partial truths. In fact, these images represent complementary development contradictions that co-exist in any major city today.  相似文献   
36.
This study examined the moderating effects of temperamental resistance to control on the link between development of sleep problems and development of externalizing behaviors over a 5-year period. Resistance to control was assessed with mothers' retrospective reports of temperament in infancy, provided when children were 5 years of age. Sleep problems were assessed with mother reports on an annual basis from age 5 to age 9. Externalizing behaviors were assessed with teacher reports on an annual basis from age 5 to age 9. A cross-domain latent growth curve model indicated that sleep problem trajectories were positively associated with externalizing behavior trajectories only for children high in resistance to control. In addition, resistance to control was positively associated with initial (age 5) sleep problems and initial (age 5) externalizing behaviors. The authors speculate that the development of sleep problems promotes the development of behavior problems for resistant children, whose self-regulatory abilities are especially tenuous. Implications for prevention and treatment of conduct problems are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
This work presents a detailed investigation of the preparation of MoVTeNbO x catalysts by hydrothermal synthesis. Phase-pure synthesis of M1 has been achieved applying the metals in a molar ratio Mo/V/Te/Nb = 1/0.25/0.23/0.12. Raman, UV/Vis spectroscopy, and SEM/EDX analysis show that the elements are inhomogeneously distributed in the initial suspension that is formed after mixing the metal salts in an aqueous medium. Iso- and heteropoly anions of molybdenum, free telluric acid as well as supra-molecular polyoxometalate clusters are observed in the solution, whereas all metals have been found in the precipitate. Complete rearrangement of molecular building blocks under hydrothermal conditions is essential for formation of phase-pure materials. Optimized synthesis conditions with respect to temperature and time result in the formation of a precursor consisting of nano-structured M1 characterized by an extended periodic organization in the [001] direction and a fairly homogeneous distribution of the elements. Residual ammonium containing supra-molecular species in the precursor result in the formation of phase mixtures during the subsequent crystallization by heat treatment in inert gas. Phase-pure M1 exhibits a distinct degree of flexibility with respect to the chemical composition that becomes obvious by incorporating Nb not exclusively into pentagonal bi-pyramidal units, but also into octahedral coordinated positions as shown by EXAFS. Anisotropic growth of the needle-like M1 crystals has been observed during the final heat treatment performed at 873–923 K in inert atmosphere disclosing a potential method to control the catalytic properties of MoVTeNbO x catalysts.  相似文献   
38.
Social and emotional competence were evaluated using self-report and behavioral measures in adults with attention-deficit/hyperactivity disorder (ADHD) and controls. Adults with ADHD viewed themselves as less socially competent but more sensitive toward violations of social norms than controls. Films depicting emotional interactions were used to assess linguistic properties of free recall and perceived emotional intensity. Although adults with ADHD used more words to describe the scenes, they used fewer emotion-related words, despite rating the emotions depicted as more intense than did controls. In contrast, no group differences for words depicting social or cognitive processes were observed. Overall, adults with ADHD appear more aware of their problems in social versus emotional skills. Findings may have implications for improving the psychosocial functioning of these adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
D-ribose, a naturally occurring pentose carbohydrate, has been shown to replenish high- energy phosphates following myocardial ischemia and high intensity, repetitive exercise. Human studies have mainly involved short-term assessment, including potential toxicity. Reports describing adverse effects of D-ribose with prolonged ingestion have been lacking. Therefore, this study assessed the toxicity of extended consumption of D-ribose in healthy adults. Nineteen subjects ingested 20 grams/Day (10 grams, twice a Day) of ribose with serial measurements of biochemical and hematological parameters at Days 0, 7, and 14. No significant toxic changes over the 14-day assessment period occurred in complete blood count, albumin, alkaline phosphatase, gamma glutamyltransferase, alanine amiotransferase, and aspartate aminotransferase. However, D-ribose did produce an asymptomatic, mild hypoglycemia of short duration. Uric acid levels increased at Day 7, but decreased to baseline values by Day 14. D-ribose consumption for 14 days appears not to produce significant toxic changes in both hematological and biochemical parameters in healthy human volunteers.  相似文献   
40.
The effective thermal diffusivity of foodstuffs was estimated from time-temperature histories in the geometric center of samples exposed to heating and cooling processes.Transfer functions methodology was used as an alternative method to estimate the thermal diffusivity assuming that conduction was the main heat transfer mechanism. The samples were characterized as delayed first-order systems with unit gain, dead time (L) and time constant (τ).The results were compared with those obtained from the fh value and with results reported in the literature.  相似文献   
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