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81.
Classwork and homework in early adolescence: The ecology of achievement   总被引:1,自引:0,他引:1  
Recent studies have questioned whether the nation's educational system is adequately preparing children to function productively in today's society. To examine this issue, the present study utilized the Experience Sampling Method to investigate the amount of time young adolescents spent doing classwork and homework, their inner subjective experience while doing so, and their companions while doing homework. The relationship between these variables and students' academic performance was also examined. Results revealed that students spent only 15.5 hours per week engaged in school work and only 6 hours per week doing homework, with increased homework time associated with better academic achievement. In addition, students were found to complete homework primarily alone or in classes, although doing homework with their parents was associated with better academic performance. Lastly, students' affect was found to be relatively neutral when doing classwork, but comparatively more negative while doing homework, particularly when doing homework alone. The implications of these findings for understanding the socializing influence of school are discussed.This research was supported by NIMH grant number MH38324, Stress in Daily Life During Early Adolescence, awarded to Reed Larson. This paper was prepared while the first author was a Schmitt Dissertation Fellow at Loyola University of Chicago.Received her Ph.D. from Loyola University of Chicago, Current Research interest are familial and intrapsychic influences on adolescents' academic performance.Current Research interests are pubertal development, precursors of eating disorders, and the effect of maternal employment on young adolescents.  相似文献   
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In order to examine the relationships among social network structure, types of social support, and determinants of support satisfaction, an alternative method was used to score the Social Support Questionnaire (SSQ). Factor analysis procedures suggested that college students' (N=198) social networks consisted of four groups: nuclear family, other family, friends, and others. Satisfaction with support was positively related to the proportion of the network occupied by nuclear family and negatively related to the proportion of friends in the network. Evidence was found for the presence of both support specialists and support generalists in the networks of the college students. These results are discussed from a developmental perspective with attention to the implications for interventions.  相似文献   
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To investigate the incidence and correlates of bulimic behavior, 1268 high school females were surveyed. A 47-item questionnaire was used to identify a group of students that would meet the DSM-III criteria for a probable diagnosis of bulimia. Students were then compared across the four content areas of demographics; body perception and weight information; dieting, exercise and menstrual behavior; and frequency of bingeing and purging behavior. Results indicated that 4.9% of the students met rigorous criteria for the diagnosis of bulimia. Between-group comparisons indicated that body dissatisfaction, drive for thinness, and chronicity of dieting differentiated the two groups.This work was supported by Biomedical Research Grant #RR5476, the Sears Allstate Foundation, and the George and Tina Barr Foundation.Main interest is eating disorders.  相似文献   
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Flouri E  Buchanan A 《危机》2002,23(1):17-22
This study of 2,722 adolescents aged 14-18 years explored whether parental involvement can protect against adolescent suicide attempts. Compared to their counterparts suicide attempters were more likely to have been in trouble with the police, to report lower levels of parental interest and academic motivation, and to report suicidal ideation and using alcohol or an illegal drug when they feel stressed. They were also less likely to reside with both parents. The association between parental involvement and suicidal behaviour was not stronger for sons than for daughters or for adolescents who had experienced family disruption than for those who grew up in two-parent families.  相似文献   
90.
Validation of a 16-locus fluorescent multiplex system   总被引:24,自引:0,他引:24  
STR multiplexes have been indispensable for the efficient genotyping of forensic samples. The PowerPlex 16 System contains the coreCODIS loci, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, THOI, TPOX, vWA, the sex determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E. This multiplex satisfies the locus requirements for most national databases and is the most efficient currently available system due to its single PCR amplification. To provide the groundwork for judicial acceptance, including the publication of primer sequences, and to evaluate laboratory-to-laboratory variation, a developmental validation for casework on this commercially available system was performed in 24 laboratories and produced the following conclusions. Amplification was reliable on a variety of thermal cyclers and product could be analyzed on either an ABI PRISM 310 Genetic Analyzer or an ABI PRISM 377 DNA Sequencer. Genotyping using single source samples was consistent between 0.25 and 2 ng of input DNA template with a few laboratories obtaining complete genotypes at 0.0625 ng. However, heterozygote allele imbalance (<60% peak height balance) caused by stochastic effects was observed at a rate of 13% with 0.125 ng DNA and 22% at 0.0625 ng DNA. Mixture analyses were done using a total of 1 ng of DNA template. Most alleles were detected in mixtures of 4 to 1 and some minor alleles were detected in mixtures of 19 to 1. Optimum amplification cycle number was dependent on the sensitivity of the detection instrument used and could also be adjusted to accommodate larger amounts of DNA on solid supports such as FTA paper. Reaction conditions including volume, annealing temperature, and concentrations of primer, AmpliTaq Gold, and magnesium were shown to be optimal yet robust enough to withstand moderate variations without affecting genotype analysis. Environmental, matrix and standard source analyses revealed an ability to obtain complete genotypes in all sample types except those exposed to 80 degrees C for 12-48 days. Finally, comparison of genotype results from the PowerPlex 16 System with other commercially available systems on non-probative reference and forensic samples showed consistent results.  相似文献   
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