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91.
Event-related potentials (ERPs) were recorded as subjects read semantically meaningful, syntactically legal but nonsensical and random word strings. The constraints imposed by formal sentence structure alone did not reduce the amplitude of the N400 component elicited by open-class words, whereas semantic constraints did. Semantic constraints also eliminated the word-frequency effect of a larger N400 for low-frequency words. Responses to closed-class words exhibited reduced N400 amplitudes in syntactic and congruent sentences, indicating that formal sentence structure placed greater restrictions on closed-class words than it did on open-class words. However, unlike the open-class results, the impact of sentence context on closed-class words was stable across word positions, suggesting that these syntactic constraints were applied only locally. A second ERP component, distinct from the N400, was elicited primarily by congruent closed-class words.  相似文献   
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Subjects were required to recall lists of six words which had been presented visually in sequence. One or two of the words might be plural nouns. A substantial number of errors occurred in which the plural form became detached from its original root. This is taken as evidence for a morpheme-based code as opposed to a unitary word code. A significantly high proportion of these errors maintained the form of the plural ( /S/, /Z/ or (ЪZ/) which is considered evidence for a primarily phonological coding of the plural morpheme. There is however a suggestion that on some occasions the plural is coded morphemically—i.e., in a way which does not distinguish between the various plural endings.  相似文献   
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A questionnaire was administered to 47 participants attending a workshop on nuclear energy shortly after publication of a report on a proposed nuclear fuel reprocessing plant. Supporters and opponents of the proposed development differed markedly in their estimates of its possible consequences, and of the relative importance of these consequences. They also differed in their endorsement of pro- and anti-nuclear lobbies, and the factors which they felt contributed most to the “quality of life”. Overall, pro-nuclear subjects appear to place emphasis on the economic benefits of nuclear energy, while anti-nuclear subjects appearad more concerned with social and political risks, and regraded alternative energy sources as more viable. It is concluded that an analysis of such attitudinal differences requires a consideration not only of differences in beliefs, but also of differences in belief salience.  相似文献   
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Counselors of unruly, runaway, truant, or delinquent children and their families run the risk of emotional overexposure– “burnout” as a result of intense client needs and problems. Survival on the job requires taking steps to avoid internalizing caseload pressures. These steps include: helping-not replacing-parents, keeping meetings brief, responding to emergencies selectively, taking simple steps first, using humor, taking care of oneself, expecting complications, avoiding panic, and knowing when to withdraw.  相似文献   
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Connections are pointed out between the concept of a cut in a graph and the data analysis problems of hierarchical clustering and seriation encountered in the social and behavioral sciences. An emphasis is placed on hierarchical clustering by the criterion of k-edge connectivity and on the relationship between several criteria for object seriation proposed in the literature and the appropriate graph-theoretical structures.  相似文献   
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This paper selectively reviews an area of operations research, refered to as normative location theory, that deals with the placement of objects in continuous space. The computational procedures discussed in this literature require initially that a certain set objects be located a priori; the placement of the objects in a second set is then determined in such a way that the total “interaction” among the fixed and variable objects is minimized. A number of strategies appropriate for different distance functions are surveyed and a numerical example is given illustrating one particular iterative algorithm. Although the current versions of these location methods depend upon more than the nonmetric information contained in the proximity measures defined for all pairs of objects, they can be generalized, and consequently, several possible connections to nonmetric multidimensional scaling are pointed out.  相似文献   
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