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121.
Participants initially completed a discrimination task (D1) involving categorization of patterns with multiple common features, each feature being partly predictive of the correct response. In a subsequent target discrimination task (D2), these features were redistributed across new discriminative stimuli. The relative predictiveness of the features in D1 was either maintained in D2 (i.e., features were equally informative in D1 and D2) or switched (i.e., more informative features in D1 were made less informative in D2, and vice versa). Differential performance on D2 suggested that features most predictive of the correct D1 responses became more highly associable than features that were less predictive in D1. This finding suggests that the associability of individual stimulus elements changes as a consequence of their role in discrimination learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
122.
In general, the diagnosis of papillary carcinoma of the thyroid is readily achieved based on a defined aggregate of histopathologic features. A papillary architecture is an important but not pivotal component of the diagnosis. The recognition of classic nuclear features is the essential diagnostic element. However, both the architectural and cytological hallmarks may be encountered in other conditions and produce problems in histopathologic interpretation. A papillary architecture may be encountered in hyperplastic areas of follicular neoplasms, multinodular goiter, and Graves' disease. Moreover, there may be scattered cells within several thyroid lesions that display some of the nuclear characteristics of papillary carcinoma. The distinction of these lesions from papillary carcinoma has important implications for clinical management. Thus, the availability of supportive diagnostic evidence would be helpful. In the authors' experience, the strong expression of S100 is of value in identifying papillary neoplasia and distinguishing it from examples of papillary hyperplasia. It is of supportive but not conclusive use in distinguishing follicular adenoma from the follicular variant of papillary carcinoma. The authors stress that the overwhelming factor in the distinction remains the identification of the nuclear characteristics of a papillary carcinoma. However, the authors have encountered several cases wherein the latter are either focal or absent for reasons addressed previously and have found immunohistochemistry a valuable adjunct to diagnosis. In examining papillary foci within Graves' disease, caution must be exercised; S100 expression is a phenomenon of the hyperplastic, hyperfunctional state. 相似文献
123.
The relationship between past body size and current body dissatisfaction among 933 middle-aged women from a prospective birth cohort study was examined. Women provided self-report data on weight esteem at age 54. Height and weight data were collected at ages 7, 11, 15, 20, 26, 36, 43, and 54. Data on reproductive variables were also collected prospectively. Hierarchical linear modeling and multiple regression analyses were used. Women who were dissatisfied at midlife were heavier at age 7 and showed a more rapid increase in body mass index with age. A late menarche, being postmenopausal, and having started hormone replacement therapy before menopause were associated with less dissatisfaction. Attention to these factors across the life span is necessary to understand body dissatisfaction in women at midlife. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
124.
The authors describe a computationally efficient model for metal oxide varistors (MOVs) suitable for use in simulation studies of series compensated lines. It can also be used in simulators running EMTP type solutions in real-time since it does not rely on an iterative technique for its implementation. The EMTP program on which this work is based is the version written by Manitoba Hydro and is called EMTDC. The line on which the studies have primarily been based is the 500 kV line from the Dorsey converter station north of Winnipeg to the Forbes substation in Minnesota. The source structure has not been represented in great detail but is adequate for examining the behavior of the MOVs. In addition, the proposed model is inserted in a simulation of a previously published study and shown to give good agreement 相似文献
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J
S McLaren 《Journal of the science of food and agriculture》2002,82(8):931-931
127.
McLaren P.G. Kuffel R. Giesbrecht J. Keerthipala W. Castro A. Fedirchuk D. Innes S. Mustaphi K. Sletten K. 《Power Delivery, IEEE Transactions on》1994,9(3):1308-1315
This paper describes tests on the relays on a long 500 kV AC line carried out on site using the RTDS (Real Time Digital Simulator) of the Manitoba HVDC Research Centre. The purpose of the tests was to examine the relay behaviour when series compensation is inserted in the line in 1993. New settings for the relays have been found which will give adequate cover for all faults although some faults will be entirely dependent on the communication link for short clearance times 相似文献
128.
The dyer's variables of ‘shade’ and strength have been interpreted in Adams-Nickerson space (ANLAB) so that measured colour differences can be expressed in familiar terms. 相似文献
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