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101.
The Childhood Trauma Questionnaire ‐ Short Form (CTQ‐SF) is widely used to measure childhood abuse of all types. In the present study, we examined the psychometric properties of the Norwegian version of the instrument. The participants constituted four subsamples (n = 517): substance abusers (n = 126), psychiatric patients (n = 210), prisoners (n = 109) and adolescents in out‐of‐home placements (n = 72). Confirmatory factor analysis revealed a reasonable fit of the data to the original five‐factor structure of the CTQ‐SF. Measurement invariance was found across gender and the four subsamples. It was concluded that the Norwegian version of the CTQ‐SF has acceptable psychometric properties, with good reliability and satisfactory accuracy, to assess different dimensions of childhood trauma.  相似文献   
102.
Abstract

This study examined the psychometric properties of the Eating Disorder Inventory (EDI) with a clinical sample of 79 female clients seen at an outpatient eating disorder program. The means and standard deviations for the bulimia nervosa subgroup in this study (n = 48) compared favorably with the bulimia group in the EDI Manual Supplement (1986) on all eight subscales, except Drive for Thinness. The present non-student sample had significantly lower scores on this particular subscale than did the norm group (mostly students). Another difference was that the local bulimic subgroup had significantly higher present and minimum weights (as a percentage of the expected average weight according to height). The EDI subscales also displayed respectable internal consistency reliability with this sample. In contrast to previous research, however, only five factors were found in a factor analysis rather than eight corresponding to the original subscales for the EDI. Differences between bulimic and a not-otherwise-specified (NOS) diagnostic groups were also found on both the EDI Ineffectiveness and Bulimia subscales (NOS had lower scores). The results of this study are discussed in terms of the importance of undertaking local standardization of tests in clinical settings.  相似文献   
103.
This article describes an example of making pediatric neuropsychological assessments more time-efficient. Empirical support, including new data, for the utilization of an eight-subtest short form of the Wechsler Intelligence Scale for Children-Third Edition (WISC-III; Wechsler, 1991) is reviewed. It is concluded that this short form of the WISC-III is a valid substitute for the complete version under most clinical circumstances, allowing the practitioner to expand on interview, history or more specific neuropsychological tests without adding financial or time burdens to the evaluation.  相似文献   
104.
The purpose of this investigation was to determine how confidence intervals (CIs) for pediatric neuropsychological norms vary as a function of sample size, and to determine optimal sample sizes for normative studies. First, the authors calculated 95% CIs for a set of published pediatric norms for four commonly used neuropsychological instruments. Second, 95% CIs were calculated for varying sample size (from n?=?5 to n?=?500). Results suggest that some pediatric norms have unacceptably wide CIs, and normative studies ought optimally to use 50 to 75 participants per cell. Smaller sample sizes may lead to overpathologizing results, while the cost of obtaining larger samples may not be justifiable.  相似文献   
105.
A key challenge in the fabrication of superhard nanocomposite films is how to control the distribution of grain sizes in these materials. High-resolution transmission electron microscopy has been used to measure nanograin-size distributions in the Ti–B–N films with various B contents. The results show that the mean grain size decreases with increase of B content and the grain-size distribution conforms to a log-normal function when the hardness approaches a maximum value. The transition from normal to log-normal distributions can be determined by analysis in terms of a minimum information criterion. The origin of a log-normal size distribution probably results from heterogeneity arising from a diffusion-drift process.  相似文献   
106.
We report on the effect of cooling rate on the size-dependent atomic ordering of CoPt nanoparticles using aberration corrected high-resolution transmission electron microscopy. It was found that cooling rate plays a crucial role in promoting atomic ordering during the cooling process after annealing. Nanoparticles of ≈3?nm in diameter show the A1-disordered phase after annealing at 873?K for 1?h followed by rapid cooling (110?K/min), while the L10-ordered phase is obtained when the cooling rate is slow (1.5?K/min). The disordered phase is also obtained by rapid cooling after annealing at 973?K for 1?h. These results unambiguously indicate that the order–disorder transformation temperature is reduced to a temperature at least lower than 873?K for CoPt nanoparticles smaller than 3?nm in diameter. The slow cooling process promotes the atomic ordering, which resulted in an enhancement of magnetic coercivity as high as 2200?Oe. This study demonstrates that hard magnetic properties of the CoPt nanoparticles can be improved by controlling the cooling rate after heat treatments.  相似文献   
107.
We show that perceived size of visual stimuli can be altered by matches between the contents of visual short-term memory and stimuli in the scene. Observers were presented with a colour cue (to hold in working memory or to merely identify) and subsequently had to indicate which of the two different-coloured objects presented simultaneously on the screen appeared bigger (or smaller). One of the two objects for size judgements had the same colour as the cue (matching stimulus) and the other did not (mismatching stimulus). Perceived object size was decreased by the reappearance of the recently seen cue, as there were more size judgement errors on trials where the matching stimulus was physically bigger (relative to the mismatching stimulus) than on trials where the matching stimulus was physically smaller. The effect occurred regardless of whether the visual cue was actively maintained in working memory or was merely identified. The effect was unlikely generated by the allocation of attention, because shifting attention to a visual stimulus actually increased its perceived size. The findings suggest that visual short-term memory, whether explicit or implicit, can decrease the perceived size of subsequent visual stimuli.  相似文献   
108.
Two models of second-order ZFC need not be isomorphic to each other, but at least one is isomorphic to an initial segment of the other. The situation is subtler for impure set theory, but Vann McGee has recently proved a categoricity result for second-order ZFCU plus the axiom that the urelements form a set. Two models of this theory with the same universe of discourse need not be isomorphic to each other, but the pure sets of one are isomorphic to the pure sets of the other.This paper argues that similar results obtain for considerably weaker second-order axiomatizations of impure set theory that are in line with two different conceptions of set, the iterative conception and the limitation of size doctrine.  相似文献   
109.
许百华  傅亚强 《心理科学》2003,26(3):397-399
采用一台有源矩阵彩色液晶显示器作为主要实验装置,对低色温、低强度背景光照射下液晶显示颜色编码范围及其与色标大小的关系进行了研究。实验结果表明:(1)液晶显示器上色标大小对绝对辨认效果有显著影响,随着色标的增大,辨认错误率随之下降,但下降率则随色标的增大而递减。(2)在色温为3100K的低强度背景光照射下,液晶显示的颜色编码范围因色标大小不同而存在显著差异,当色标面积减小到1×1mm2至2×2mm2时,编码色数目仅限于3-4种。  相似文献   
110.
Control by sample location in pigeons'' matching to sample.   总被引:6,自引:6,他引:0       下载免费PDF全文
Three experiments assessed the impact of sample location in pigeons' matching to sample. Experiments 1 and 2 demonstrated that after line or hue identity matching was acquired to high levels of accuracy with center-key samples, varying sample location across the three keys disrupted performances. The drop in accuracy occurred following both zero-delay and simultaneous training and was mostly confined to trials in which the sample appeared on a side key. Experiment 3 attempted to diminish control by location by training birds to match samples that could appear in any location prior to center-key sample training and moving-sample testing with another set of stimuli. In testing, all birds performed accurately on center-sample trials and on side-key sample trials in which the matching choice appeared on the center key. Accuracy was below chance, however, on side-key sample trials in which the matching choice appeared on the other side key. One implication of the persistent control by sample location in the three-key paradigm is that it precludes the possibility of symmetry because symmetry tests require a change in the locations at which samples and comparisons appear.  相似文献   
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