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291.
The levels of 20 amino acids were measured in the plasma and cerbrospinal fluid of 41 patients with endogenic depressions. The plasma levels of 12 amino acids were found to be significantly lower in the patients than in the control group, but cerebrospinal fluid levels were significantly lower only in the case of taurine, glutamine, phenylalanine and aginine. Comparison of the same amino acid levels in treated and non-treated patients showed that serine and alpha-aminobutyric acid serum concentrations were higher in the nontreated patients. The tyrosine and phenylalanine levels in the cerebrospinal fluid of the patients who had received medicamentous treatment were higher than in the other group.  相似文献   
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293.
In this paper a propositional logic of viewpoints is presented. The language of this logic consists of the usual modal operatorsL (of necessity) andM (of possibility) as well as of two new operatorsA andR. The intuitive interpretations ofA andR are “from all viewpoints” and “from some viewpoint”, respectively. Semantically the language is interpreted by using Kripke models augmented with sets of “viewpoints” and with a new alternativeness relation for the operatorA. Truth values of formulas are evaluated with respect to a world and a viewpoint. Various axiomatizations of the logic of viewpoints are presented and proved complete. Finally, some applications are given.  相似文献   
294.
Nondeterministic programs occurring in recently developed programming languages define nondeterminate partial functions. Formulas (Boolean expressions) of such nondeterministic languages are interpreted by a nonempty subset of {T (“true”), F (“false”), U (“undefined)}. As a semantic basis for the propositional part of a corresponding nondeterministic three-valued logic we study the notion of a truth-function over {T, F, U} which is computable by a nondeterministic evaluation procedure. The main result is that these truth-functions are precisely the functions satisfying four basic properties, called \( \subseteq \) -isotonic, \( \subseteq \) ?-isotonic, hereditarily guarded, and hereditarily guard-using, and that a function satisfies these properties iff it is explicitly definable (in a certain normal form) from “if..then..else..fi”, binary choice, and constants.  相似文献   
295.
The Draw-a-Person test was used to evaluate a number of questions regarding children referred for potential problems in their gender-identity development (N = 36). Sibling (N = 31), psychiatric (N = 23), and normal (N = 30) children served as comparison groups. The major results included the following: (1) The gender-referred children were more likely to draw an opposite-sex person when requested to "draw a person" than were the other three groups; (2) the gender-referred children who drew an opposite-sex person were more likely to play with opposite-sex toys and dress-up apparel on a free-play task than were the gender-referred children who drew a same-sex person; (3) the gender-referred children drew taller opposite-sex persons than same-sex persons; (4) using Koppitz's (1968) criteria, the normal children had a smaller proportion of emotional disturbance indicators in their same-sex drawings than did the other three groups. These findings were discussed with regard to psychometric and interpretive issues in the assessment of children with atypical gender-role behavior.  相似文献   
296.
While several guidelines for avoiding sexist language in career materials have been published, little empirical evidence exists to support the assumption that sexist language in career information has deleterious effects on clients. The purpose of this study was to explore the effects of sex-biased language in occupational information on subject interest and attitudes regarding gender appropriateness of occupations. Eighth-grade students read occupational briefs on two occupations presented in either neutral, female-biased, or male-biased language. Results showed a nonsignificant language effect and a significant sex difference in interest in the occupations. A significant three-way interaction (language by subject sex by occupation) was found for gender-appropriateness ratings. The findings, together with previous research, suggest that language may have little impact on specific occupational interests, but may affect other career attitudes related to interests.  相似文献   
297.
Group learned helplessness is demonstrated in Experiment I. Groups of 2 tried to turn off noise by their joint action. In the solvable group (S), noise offset was contingent on their sequence of button pushing. In the yoked, unsolvable group (U), noise offset was independent of all sequences of button pushes they produced. In a practice group (O). subjects practiced coordinated sequences of button pushes with their partners, but heard no noise. Later, all 3 groups were tested in pairs in a shuttlebox which required coordinated joint responding to turn off noise. The unsolvable group escaped more poorly than the other 2 groups, paralleling helplessness effects with individuals. Experiment 2 and 3 found no transfer from individual helplessness training to group testing and no transfer from group helplessness training to individual testing. We suggest that the same mechanism, the expectation of response ineffectiveness, may mediate both individual and group learned helplessness.  相似文献   
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299.
Similarity ratings of pairs of lipread consonants were obtained using a 5-point scale. Matrices were constructed showing mean similarity ratings and confusions among stimuli. Both the similarity and the confusion data provide normative data useful for researchers in many areas. Lipread data collected here are compared with similarity ratings of orthographically and auditorily presented consonants collected by Manning (1977). These comparisons provide information about how stimulus similarity both within and between presentation formats may affect information processing of the three types of stimuli. These data are of special interest to researchers studying the visual processing of speech and the effect of format of presentation on recall.  相似文献   
300.
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