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61.
This article presents an approach we have developed for the assessment of public research institutions in the natural sciences and engineering. The method consists in the exploitation of available S&T databases and indicators, including bibliometrics (databases of scientific as well as technical literature), patents, and internal data. Results are therefore derived through multiple databases. The objective is to profile a specific national R&D community in order to assess the positioning of a public institution or program within the community to which it belongs. It involves obtaining the profile of the evolution of an R&D area, the R&D performers, the financing and support institutions, the users of R&D results, and the interactions between all these actors. A case-study of Canadian research in polymers is presented. Part of this research was financed by the National Research Council of Canada, and by a strategic grant from the Social Sciences and Humanities Research Council. The research benefited from the expertise of Robert Letellier, Robert H. Marchessault, Jacques Martel, and Marielle Piché, and from the technical assistance of Maryse Prud’homme, Marcel Parent, and Benoit Longpré.  相似文献   
62.
The increased use of CRT monitors for displaying and controlling stimuli in studies of surface color poses problems of comparability with data obtained with traditional paper-and-illuminant methods. A review of comparable studies using the two methodologies revealed that CRT studies tend to report larger contrast effects. To investigate factors that may be responsible for this difference, simultaneous lightness contrast was measured using both CRT and paper-and-illuminant presentations. The spatial distribution of luminance in the whole field of view and the visual angles subtended by the displays were controlled. The CRT presentation yielded contrast effects twice as big as those measured for a paper surface in a homogeneously illuminated room. However, a paper display under Gelb lighting yielded almost exactly the same effect size as that measured in the CRT presentation. These results demonstrate that contrast effects in both modes of presentation are affected by the spatial distribution of luminance beyond the basic experimental stimuli.  相似文献   
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The purpose of this clinical experiment was to investigate the manipulability of a Factor II avoidance response (arm movement). The substantive hypothesis under test was that its suppression would be enhanced by repeated punishment sessions. During the first of nine therapy sessions response-contingent negative stimulation was not delivered. In the next five, after a base-rate period, “wrong” was made consequent upon the target response. In each of these sessions the suppression of arm movement was apparent. However, the magnitude of the suppression decreased from session to session. Evidently, the continued use of punishment did not enhance suppression. Because of this finding procedural changes were introduced in the next three therapy sessions. Verbal praise was added as a consequence of increasingly stringent omission criteria and three consecutive units of praise led to time-out from the reportedly fatiguing task of continuous speech. A marked reduction and then complete extinction resulted. Moreover, learning was evidenced since the frequency of arm movement lessened in the base-rate period of each session.  相似文献   
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Comprehension of language and visuo-spatial abilities were studied in 12 surgical patients with left cerebral lesions and right-hemisphere speech representation verified by sodium amobarbital tests. When left-hemisphere symptoms preceded the acquisition of speech, impaired understanding of syntactically complex sentences was associated with an early, but not late, onset of convulsive seizures. Other behavioral measures did not show a similar effect of age at seizure onset. Sparing or loss of comprehension could not be related to any aspects of the neurological histories in cases with right-hemisphere speech acquired before the onset of left-hemisphere symptoms. Factors which may have influenced the development of right-hemisphere language comprehension are discussed.  相似文献   
67.
The concept “impossible figure” is analyzed by formalizing the interpretations of a polyhedral figure by an observer, and defining several types of inconsistency in such interpretations. Tests for these inconsistencies are developed using simple graph theory, and a sufficient condition is established for the feasibility of an interpretation. Finally, techniques are derived for the automatic construction of usual or unusual multibar figures.  相似文献   
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The aim of this study was to investigate the possible relations between specific personality variables and the effect of subliminal stimulation on choice behavior. It was hypothesized that subjects with low anxiety, less neuroticism, and external locus of control and the trait of extraversion would be more susceptible to subliminal stimulation. 38 undergraduate students were exposed to subliminal messages urging them to choose symbols instead of numbers or letters. Analysis showed that subliminal stimulation did not generate a preference for symbols over numbers or letters. No support was observed for the hypothesis of an association between susceptibility and personality variables. These results may be explained in terms of symbol choice being a neutral message that did not relate to the subjects' needs and motivation.  相似文献   
70.
Analysis of the elements of attention: A neuropsychological approach   总被引:15,自引:0,他引:15  
A model for conceptualizing the components or elements of attention is presented. The model substitutes for the diffuse and global concept of attention a group of four processes and links them to a putative system of cerebral structures. Data in support of the model are presented; they are derived from neuropsychological test scores obtained from two samples, the first consisting of 203 adult neuropsychiatric patients and normal control subjects, and the second, an epidemiologically-based sample of 435 elementary school children. Principal components analyses of test scores from these two populations yielded similar results: a set of independent elements of attention that are assayed by different tests. This work presents a heuristic for clinical research in which the measurement of attention is essential.  相似文献   
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