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991.
Jane E. Fleming Thomas D. Cook C. Addison Stone 《Learning disabilities research & practice》2002,17(1):47-64
This study examined the effects of social influences in the lives of an ethnically diverse sample of fifth through eighth grade students with and without learning disabilities (LD) using survey data and academic achievement scores collected in 19 Chicago public schools from 1993–1997. Similarities and differences in student perceptions of school, family, and peer group contexts were examined. In addition, longitudinal data were analyzed using hierarchical linear modeling (HLM) to identify contextual influences on changes in student reading achievement over time. Comparisons of student responses confirm and extend existing findings in the literature concerning the perceptions of students with LD of their social environments. In particular, having a learning disability was associated with consistent, mostly negative, effects on social relations across the contexts of students’ lives, regardless of gender, race, grade, and socioeconomic status. In addition, student perceptions of their friendship groups were found to have small, but significant, effects on their growth in reading achievement over the course of middle school. While students with and without LD had somewhat different views of their social contexts, the processes working within these environments appeared to affect their reading achievement in similar ways. The results suggest that careful attention should be paid to the social contexts of students’ lives when planning academic interventions. 相似文献
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Kenneth R. Pugh W. Einar Mencl Annette R. Jenner Jun Ren Lee Leonard Katz Stephen J. Frost Sally E. Shaywitz Bennett A. Shaywitz 《Learning disabilities research & practice》2001,16(4):240-249
Converging evidence from a number of neuroimaging studies, including our own, suggest that fluent word identification in reading is related to the functional integrity of two left hemisphere posterior systems: a temporo-parietal system and a ventral occipito-temporal system. These posterior systems are functionally disrupted in developmental dyslexia. Reading disabled, relative to nonimpaired, readers demonstrate heightened reliance on both inferior frontal and right hemisphere posterior regions, presumably in compensation for the LH posterior difficulties. We propose a neurobiological account suggesting that for normally developing readers the temporo-parietal system predominates at first, and is associated with aspects of processing critical in learning to integrate orthography with phonological and lexical-semantic features of printed words. The occipito-temporal system, by contrast, constitutes a fast, late-developing, word-identification system that underlies fluent word recognition in skilled readers. 相似文献
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Six Danish male cross-country skiers were studied during the end-of-summer and winter seasons. Their maximal oxygen uptake was measured while running on a treadmill and using a ski ergometer incorporating the double-poling technique. Maximal oxygen uptake during treadmill running and double-poling was correlated with performance, expressed as a ranking score during 10 ski races. The tests were undertaken in September, December and April. Upper body maximal oxygen uptake increased 5.8% from September to December, decreasing to 2.3% above the September level in April. Upper body work output (2 min at maximal intensity) increased 11.8% from September to December (P less than 0.05). The relationship between upper body and leg maximal oxygen uptake--the upper body/leg ratio--was 89.4% in September. In four skiers, both treadmill and upper body tests were undertaken on each test occasion. The upper body/leg ratio changed from 87.7% in September to 95.7% in December. In April, the ratio was 91.0%. The maximal oxygen uptake measured using the ski ergometer during double-poling was significantly correlated with performance (P less than 0.05). It is concluded that the upper body ski ergometer can be used in the evaluation of elite cross-country skiers. 相似文献
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