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41.
This study used semistructured interviews and grounded theory to look for characteristics among college undergraduates that predicted persistence into Ph.D. and M.D./Ph.D. training. Participants in the summer undergraduate and postbaccalaureate research programs at the Mayo Clinic College of Medicine were interviewed at the start, near the end, and 8–12 months after their research experience. Of more than 200 themes considered, five characteristics predicted those students who went on to Ph.D. and M.D./Ph.D. training or to M.D. training intending to do research: 1) Curiosity to discover the unknown, 2) Enjoyment of problem solving, 3) A high level of independence, 4) The desire to help others indirectly through research, and 5) A flexible, minimally structured approach to the future. Web-based surveys with different students confirmed the high frequency of curiosity and/or problem solving as the primary reason students planned research careers. No evidence was found for differences among men, women, and minority and nonminority students. Although these results seem logical compared with successful scientists, their constancy, predictive capabilities, and sharp contrast to students who chose clinical medicine were striking. These results provide important insights into selection and motivation of potential biomedical scientists and the early experiences that will motivate them toward research careers. 相似文献
42.
Stress exposure and reactivity models were examined as explanations for why girls exhibit greater levels of depressive symptoms than boys. In a multiwave, longitudinal design, adolescents' depressive symptoms, alcohol usage, and occurrence of stressors were assessed at baseline, 6, and 12 months later (N=538; 54.5% female; ages 13-18, average 14.9). Daily stressors were coded into developmentally salient domains using a modified contextual-threat approach. Girls reported more depressive symptoms and stressors in certain contexts (e.g., interpersonal) than boys. Sex differences in depression were partially explained by girls reporting more stressors, especially peer events. The longitudinal direction of effects between depression and stressors varied depending on the stressor domain. Girls reacted more strongly to stressors in the form of depression. 相似文献
43.
Veenstra R Lindenberg S Zijlstra BJ De Winter AF Verhulst FC Ormel J 《Child development》2007,78(6):1843-1854
For this study, information on Who Bullies Who was collected from 54 school classes with 918 children (M age = 11) and 13,606 dyadic relations. Bullying and victimization were viewed separately from the point of view of the bully and the victim. The two perspectives were highly complementary. The probability of a bully-victim relationship was higher if the bully was more dominant than the victim, and if the victim was more vulnerable than the bully and more rejected by the class. In a bully-victim dyad, boys were more often the bullies. There was no finding of sex effect for victimization. Liking reduced and disliking increased the probability of a bully-victim relationship. 相似文献
44.
Theory-of-mind (ToM) abilities were studied in 176 deaf children aged 3 years 11 months to 8 years 3 months who use either American Sign Language (ASL) or oral English, with hearing parents or deaf parents. A battery of tasks tapping understanding of false belief and knowledge state and language skills, ASL or English, was given to each child. There was a significant delay on ToM tasks in deaf children of hearing parents, who typically demonstrate language delays, regardless of whether they used spoken English or ASL. In contrast, deaf children from deaf families performed identically to same-aged hearing controls (N=42). Both vocabulary and understanding syntactic complements were significant independent predictors of success on verbal and low-verbal ToM tasks. 相似文献
45.
This longitudinal study of 105 economically disadvantaged children examined the relation between reading problems and internalizing behavior in 3rd- and 5th-grade assessments (8- to 12-year olds). The variable-centered results showed that reading problems predicted change in internalizing behavior in the context of child and family predictors. The person-centered results showed that children with reading problems in both grades had higher internalizing scores in 5th grade but not in 3rd grade than children with reading problems in 3rd grade or no problems. Child-reported negative emotion experiences varied similarly across grade. The results tie reading problems to emotional distress in school and support conclusions about the direction of effects and the internalization of academic difficulty for disadvantaged children. 相似文献
46.
The use of function words in 135 essays written by deaf college underclassmen in developmental and credit-bearing English composition classes is described and compared with Standard English (SE) versions of teh same essay. If student and SE version were the same, this was considered mastery; if the student omitted a word, this was considered avoidance; and if the student added a word, this was considered overuse. The deaf students varied from SE more for function than for content words. They demonstrated low mastery of independent clause markers, demonstratives, third-person singular neuter pronouns, and modals related to possibility, but had relatively high mastery of the first-person singular; and some punctuation. These students strongly avoided some dependent clause markers, some demonstratives, the indefinite article, punctuation except for periods and commas, and the modal verbs may, might and should , but greatly overused other dependent clause markers, the second person and third-person pronouns, quantifiers, the verb do, and the modals could and will. They were also more likely to produce run-ons than fragments. 相似文献
47.
This article examines how 31 triads of 6- to 10-year-old children from 3 cultural backgrounds organized their interactions while folding Origami figures. Triads of children whose families had immigrated to the United States from indigenous heritage regions of México (and whose mothers averaged only 7 grades of schooling) coordinated more often as an ensemble, whereas triads of European heritage U.S. children whose mothers had extensive schooling more often engaged dyadically or individually. When the European heritage children did engage as an ensemble, this often involved chatting rather than nonverbal conversation regarding folding, which was more common among the Mexican heritage children. Mexican heritage U.S. triads whose mothers had extensive schooling showed an intermediate pattern or resembled the European heritage children. 相似文献
48.
Why are hyperactivity and academic achievement related? 总被引:1,自引:0,他引:1
Although a negative association between hyperactivity and academic achievement is well documented, little is known about the genetic and/or environmental mechanisms responsible for the association. The present study explored links between parent and teacher ratings of hyperactive behavior problems and teacher-assessed achievement in a sample of 1,876 twin pairs (mean age 7.04 years). The results did not differ across rater, nor were there significant differences between males or females or for twins in the same or different classrooms. Hyperactivity was significantly correlated with achievement. Multivariate model-fitting analyses revealed significant genetic and nonshared environmental covariance between the two phenotypes. In addition, bivariate heritabilities were substantial, indicating that the phenotypic correlations between hyperactivity and achievement were largely mediated by genetic influences. 相似文献
49.
Ortiz R Jiménez JE García Miranda E Guzmán Rosquete R Hernández-Valle I Rodrigo M Estévez A Díaz A Hernández Expósito S 《Journal of learning disabilities》2007,40(1):80-92
The aims of this study were (a) to determine whether Spanish children with reading disabilities (RD) show a speech perception deficit and (b) to explore the locus and nature of this perceptive deficit. A group of 29 children with RD, 41 chronological age-matched controls, and 27 reading ability-matched younger controls were tested on tasks of speech perception. The effect of linguistic unit (word vs. syllable) and type of phonetic contrast (voicing, place and manner of articulation) were analyzed in terms of the number of errors and the response time. The results revealed a speech perception deficit in Spanish children with RD that was independent of the type of phonetic contrast and of linguistic unit. 相似文献
50.
Cognition-related brain responses to meaningful and meaningless figures were registered in 5-year-old kindergarten children who either had been subtyped as being at-risk of developing an L- or P-type dyslexia (LAL versus LAP) or who were not at-risk. While identifying, naming, or categorizing pictures, event-related potentials (ERP) were registered. Three cognition-related components were found: the N460, the P780, and the Slow Wave (SW). LAP-children produced weak N460 activity across tasks, whereas LAL children, and to a lesser degree, non-risk children produced robust task-dependent activity. This finding may indicate that LAP-children lack semantic input while processing the figures. P780 latencies to frequently occurring figures were found hemisphere-dependent: LAP-children showed longer latencies in the right than in the left hemisphere, whereas the distribution was reversed in the LAL and non-risk children. It was also found that the right hemisphere is generally responsible for a lion's share of the processing of figures and therefore it seems that the right hemisphere of LAP-children invests ample time in doing so. Whereas LAP-children showed largest SW amplitude differences between frequent and infrequent stimuli at posterior locations, LAL children did so at frontal locations. Assuming that the SW represents working-memory processes, it may be that working-memory in LAP-children deals with figure-relevant visual-spatial information and with figure-derived concepts in LAL children. Overall, the findings suggest that LAL and LAP represent two different groups of kindergartners at risk of dyslexia and that these differences, to some degree, fit with the presumed etiology of L- and P-type dyslexia. 相似文献