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101.
Mórocz IA Janoos F van Gelderen P Manor D Karni A Breznitz Z von Aster M Kushnir T Shalev R 《International journal of imaging systems and technology》2012,22(1):81-96
The aim of this article is to report on the importance and challenges of a time-resolved and spatio-temporal analysis of fMRI data from complex cognitive processes and associated disorders using a study on developmental dyscalculia (DD). Participants underwent fMRI while judging the incorrectness of multiplication results, and the data were analyzed using a sequence of methods, each of which progressively provided more a detailed picture of the spatio-temporal aspect of this disease. Healthy subjects and subjects with DD performed alike behaviorally though they exhibited parietal disparities using traditional voxel-based group analyses. Further and more detailed differences, however, surfaced with a time-resolved examination of the neural responses during the experiment. While performing inter-group comparisons, a third group of subjects with dyslexia (DL) but with no arithmetic difficulties was included to test the specificity of the analysis and strengthen the statistical base with overall fifty-eight subjects. Surprisingly, the analysis showed a functional dissimilarity during an initial reading phase for the group of dyslexic but otherwise normal subjects, with respect to controls, even though only numerical digits and no alphabetic characters were presented. Thus our results suggest that time-resolved multi-variate analysis of complex experimental paradigms has the ability to yield powerful new clinical insights about abnormal brain function. Similarly, a detailed compilation of aberrations in the functional cascade may have much greater potential to delineate the core processing problems in mental disorders. 相似文献
102.
Two studies examined the novel proposal that implicit theories of intelligence (C. S. Dweck & E. L. Leggett 1988) moderate both the effects of performance trends on ability inferences and the perceived diagnosticity of temporal versus normative feedback. Results from 613 adolescents and 42 teachers confirmed that entity theorists perceived initial outcome as more diagnostic and inferred higher ability in another (Study 1) and in the self (Study 2) in a declining outcome condition; incremental theorists perceived last outcome as more diagnostic and inferred higher ability in an ascending condition. Experimental induction of beliefs about ability had similar effects. As predicted, self-appraisal was affected more by temporal feedback among incremental theorists and by normative feedback among entity theorists. Results help resolve prior mixed findings regarding order effects and responses to temporal and normative evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Ruth F. Curtain 《Mathematics of Control, Signals, and Systems (MCSS)》2001,14(4):299-337
We consider the question of the existence of solutions to certain linear operator inequalities (Lur'e equations) for strongly
stable, weakly regular linear systems with generating operators A, B, C, 0. These operator inequalities are related to the spectral factorization of an associated Popov function and to singular
optimal control problems with a nonnegative definite quadratic cost functional. We split our problem into two subproblems:
the existence of spectral factors of the nonnegative Popov function and the existence of a certain extended output map. Sufficient
conditions for the solvability of the first problem are known and for the case that A has compact resolvent and its eigenvectors form a Riesz basis for the state space, we give an explicit solution to the second
problem in terms of A, B, C and the spectral factor. The applicability of these results is demonstrated by various heat equation examples satisfying
a positive-real condition. If (A, B) is approximately controllable, we obtain an alternative criterion for the existence of an extended output operator which
is applicable to retarded systems. The above results have been used to design adaptive observers for positive-real infinite-dimensional
systems.
Date received: July 25, 1997. Date revised: February 10, 2001. 相似文献
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Gomez Maria J.; Fassinger Ruth E.; Prosser Joann; Cooke Kathleen; Mejia Brenda; Luna Jeanette 《Canadian Metallurgical Quarterly》2001,48(3):286
This study used qualitative methodology to investigate the career development of 20 notable Latinas. The emergent theory proposed that Latina career development is influenced by sociopolitical, cultural, contextual, and personal variables. Results suggested that (a) career paths tended to be unplanned and nonlinear; (b) background variables, socioeconornic status, and educational experiences influenced the participants' sense of self and career motivation; (c) family, culture, and cultural identity werr influential; (d) relational support systems, particularly those that involved extended family, spouses, and mentors, were important; and (e) the participants' optimism, persistence, passion, and capacity for cognitive reframing helped them cope with challenges and remain true to their values, beliefs, and sense of self. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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557 Asian-American students (263 Chinese Americans, 185 Japanese Americans, and 109 Korean Americans) completed a survey consisting of a demographic questionnaire, a modified version of the Suinn-Lew Asia Self-Identity Acculturation Scale, and the Attitudes Toward Seeking Professional Psychological Help Scale (ATSPHS). A 3?×?2?×?2 multivariate analysis with main effects of ethnicity, gender, and level of acculturation and the 4 subscales of the ATSPHS as the dependent variables resulted in a significant F value for acculturation effect and nonsignificant F values for all other main and interaction effects. Regardless of ethnicity and gender, the most acculturated students were: (a) most likely to recognize personal need for professional psychological help, (b) most tolerant of the stigma associated with psychological help, and (c) most open to discussing their problems with a psychologist. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Farmer Thomas W.; Leung Man-Chi; Pearl Ruth; Rodkin Philip C.; Cadwallader Thomas W.; Van Acker Richard 《Canadian Metallurgical Quarterly》2002,94(3):611
This study examined peer affiliations of aggressive children in a sample of 948 students (496 girls, 452 boys) from 59 elementary classrooms (4th-6th grades). Groups were identified as zero aggressive, nonaggressive, aggressive, and mixed. The deviant peer group hypothesis was partially supported. Two thirds of aggressive boys and one half of aggressive girls were members of nonaggressive or mixed peer groups. Unpopular aggressive boys were most likely to be members of nonaggressive groups, whereas popular aggressive boys were most likely to be in aggressive and mixed groups. Aggressive and nonaggressive associates tended to he similar on key social characteristics (i.e., popularity, athleticism, leadership). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献