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971.
972.
The purpose of this study was twofold: (1) to examine the factor structure of behavior exhibited in the regular classroom in order to provide a conceptual framework for classifying problem behavior relevant to the classroom setting, and (2) to determine the extent to which the factors generated from ratings of regular classroom children are similar to those generated from ratings of mainstreamed special education children. Thirty-five elementary-school teachers completed behavior ratings of all of their 876 students utilizing a group-administered adapted version of the Devereux Elementary School Behavior Rating Scale. The factor analysis yielded five factors defined as Conduct Problem, Personality Problem, Adaptive Classroom Behavior, Inadequacy-Immaturity, and Achievement Anxiety. Coefficients of factorial congruence confirmed the similarity between the pattern generated from ratings of regular students and that of mainstreamed students.  相似文献   
973.
Two main questions were asked regarding young children's beliefs about causal mediation: What sorts of beliefs about causal mediation are reflected by children's incomplete explanations of causal situations? In particular, do children hold a false belief in action at a distance or do they realize that something must mediate between cause and effect? When presented with a non-visible connection between cause and effect (Experiment I), the children's incomplete (Piagetion Stage 1) explanations either reflected the correct expectation of a mediating connection or else merely reflected identification of the causal agent and no concern one way or another with the issue of causal mediation. This was also the case when the mediating connection was visible and present at the outset (Experiment II). In neither experiment (both of which involved mechanical causation) was there evidence of a false belief in action at a distance. A third experiment involved instances of electrical causation in order to maximize the chances of tapping a false belief. The rationale was that, in their everyday lives, although children do have first-hand experience with the mediating connection in instances of mechanical causation, they do not have such experience with instances of electrical causation. The results from the third experiment were analogous to the results in the other two. It was concluded that, with respect to instances of physical causality, young children do not hold a false belief (in action at a distance) that is later relinquished. Rather, their concerns are, at first, restricted to identifying the causal agent and do not include any beliefs, true or false, about the issue of causal mediation. When they eventually do deal with the question of causal mediation, children hold approximately correct beliefs. In terms of school situations, these findings suggest a shift from providing the child with disconfirming data that will aid him in relinquishing his false beliefs to providing him, instead, with additional data that will supplement his existing, approximately correct beliefs.  相似文献   
974.
Data on sex-role socialization patterns of 29 African and 79 non-African societies were analyzed to test a set of hypotheses about the extent of sex-typing displayed in the child-training processes of African societies. Findings suggest that clear sex differences in socialization emphases and behavioral outcomes exist within African societies; moreover, such differentials resemble those reported among societies from other world cultural regions. In addition, three interesting secondary findings suggest that (1) males experience greater overall levels of socialization anxiety than females; (2) greater overall normative pressure is exerted on males than females in the course of child training; (3) in the aggregate, male children tend to be more compliant in reproducing ideal role-related behavior patterns than female children.  相似文献   
975.
Problems specific to the study of gender differences — terminology, conceptualization, commonsense beliefs, evaluation and objectivity — are considered before reviewing reports of differences in psychological and social behaviour. Exploration of the interrelation of individual psychological and social variables is followed by reflection on the nature of an adequate theory of gender differentiation.  相似文献   
976.
Gender and motivation in high school mathematicsclass were examined by using an expectancy-valueframework. There were 366 students (146 males, 212females)from a school with an enrollmentof approximately 1900 students (81% Caucasian, 8% NativeAmerican, 5% Hispanic, 4% African American, and 2%Asian). These students completed a questionnaireconsisting of 92 items which measured students'situation-specific goals (4 subscales), task-specific values (3subscales), task-specific beliefs (3 subscales), andgender self-schemata (2 subscales). Students' percentagegrade in math and selfreported effort in math class were the dependent variables. The three sets oftask-specific variables each accounted for between 11%and 14% of variance in achievement, while the genderself-schemata variables contributed another 2%. Task-specific goals were much strongerpredictors of effort than any other set of variables. Anunexpected finding was that, for both males and females,endorsing the stereotype that mathematics is a male domain was negatively related to reportedeffort. There were also differences in the prediction ofachievement and effort based on gender and math classtype (required or elective). Several path models supported these results.  相似文献   
977.
A System for Relational Reasoning in Human Prefrontal Cortex   总被引:7,自引:0,他引:7  
The integration of multiple relations between mental representations is critical for higher level cognition. For both deductive- and inductive-reasoning tasks, patients with prefrontal damage exhibited a selective and catastrophic deficit in the integration of relations, whereas patients with anterior temporal lobe damage, matched for overall IQ but with intact prefrontal cortex, exhibited normal relational integration. In contrast, prefrontal patients performed more accurately than temporal patients on tests of both episodic memory and semantic knowledge. These double dissociations suggest that integration of relations is a specific source of cognitive complexity for which intact prefrontal cortex is essential. The integration of relations may be the fundamental common factor linking the diverse abilities that depend on prefrontal function, such as planning, problem solving, and fluid intelligence.  相似文献   
978.
We review the literature on children whose mothers are incarcerated in jails or prisons. These children typically experience a great many risk factors besides their mothers' incarceration, including poverty, drug and alcohol problems in their families, community violence, and multiple changes in caregivers. Children's lives are greatly disrupted when mothers are arrested, and most children show emotional and behavioral problems. The impact this has depends on the age of the child, the alternate caregiving arrangements, and the course of the mother's incarceration. Children of incarcerated mothers experience internalizing (fear, withdrawal, depression, emotional disturbance) and externalizing (anger, fighting, stealing, substance abuse) problems, as well as heightened rates of school failure and eventual criminal activity and incarceration. Research in this area is scarce and often of poor quality. A research agenda which is guided by a transactional, ecological, and developmental model, and which examines children's well-being over the course of the mothers' incarceration is suggested.  相似文献   
979.
Neurotrophic factors, including BDNF and NT-3, have been implicated in the regulation of synaptic transmission and plasticity. Previous attempts to analyze synaptic transmission and plasticity in mice lacking the NT-3 gene have been hampered by the early death of the NT-3 homozygous knockout animals. We have bypassed this problem by examining synaptic transmission in mice in which the NT-3 gene is deleted in neurons later in development, by crossing animals expressing the CRE recombinase driven by the synapsin I promoter to animals in which the NT-3 gene is floxed. We conducted blind field potential recordings at the Schaffer collateral–CA1 synapse in hippocampal slices from homozygous knockout and wild-type mice. We examined the following indices of synaptic transmission: (1) input-output relationship; (2) paired-pulse facilitation; (3) post-tetanic potentiation; and (4) long-term potentiation: induced by two different protocols: (a) two trains of 100-Hz stimulation and (b) theta burst stimulation. We found no difference between the knockout and wild-type mice in any of the above measurements. These results suggest that neuronal NT-3 does not play an essential role in normal synaptic transmission and some forms of plasticity in the mouse hippocampus.  相似文献   
980.
Substantial progress in handling scientific misconduct cases has been made since the first cases were investigated by the NIH Office of Scientific Integrity in 1989. The successor Office of Research Integrity (ORI) has simultaneously reduced the backlog of cases and increased the professionalism with which they are handled. However, a spate of lawsuits against universities, particularly those brought under the federal False Claims Act, threatens to undermine the ORI by encouraging use of the courts as an alternate route for resolving claims of research misconduct. Next steps should include establishing a government-wide definition of scientific misconduct, providing immunity from lawsuits for institutions that follow proper procedures in investigating charges of scientific misconduct, and participating in the development of international guidelines for maintaining scientific integrity. An earlier version of this paper was presented at the symposium entitled “Misconduct in Science: A Decade of Progress or Merely Years of Controversy” held during the Annual Meeting of the American Association for the Advancement of Science, Philadelphia, Pennsylvania, 13 February, 1998.  相似文献   
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