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Sports Engineering - A Monark cycle ergometer is a device globally used in physiological studies to measure the work and energy levels of exercising humans. In this paper a rope-braked cycle... 相似文献
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Direct and indirect measures were used to compare the written language abilities of three groups of college students: two with learning disabilities and one without learning disabilities. Main effects were found for group, but not gender. Differences between nonlearning disabled students (NLD) and those with learning disabilities (LD) in writing were evident on both types of measures. Performance by LD students with disabilities in an area other than writing differed depending on the type of measure and often was no different from either of the other two groups. The combined use of direct and indirect measures appeared most effective for examining the complexities of writing produced by all groups. 相似文献
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The present study examined three hypotheses regarding the consequences of early brain damage for academic achievement: First, early brain insults will have a negative impact on achievement, even in children with normal intelligence. Second, underachievement in these children will be at least partially independent of IQ (i.e., not fully accounted for by a lowering of IQ within the average range). Third, normally intelligent children with histories of brain insult will also manifest selective cognitive dysfunctions. To test these hypotheses, we compared two groups of children who had recovered from Haemophilus influenzae type b meningitis. The "complicated" group consisted of children who, as a consequence of having sustained neurologic complications during their illness, were more likely to have had brain insults. Children in the "uncomplicated" group did not have complications with their illness and were regarded as having escaped significant central nervous system (CNS) pathology. Only children with normal hearing and a prorated Full Scale IQ of at least 80 (WISC-R) were considered. Group differences on the Wide Range Achievement Test-Revised were consistent with the first two hypotheses. Although the two groups had similar Verbal IQs, the complicated group also had a lower mean Performance IQ and performed less well on perceptually demanding neuropsychological tasks. Findings suggest that learning disabilities may have selective, brain-related cognitive antecedents; but they challenge the practice of using IQ criteria for clinical diagnosis. 相似文献
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William J. Therrien Jonte C. Taylor John L. Hosp Erica R. Kaldenberg Jay Gorsh 《Learning disabilities research & practice》2011,26(4):188-203
Although science has received much attention as a political and educational initiative, students with learning disabilities (LD) perform significantly lower than their nondisabled peers. This meta‐analysis evaluates the effectiveness of instructional strategies in science for students with LD. Twelve studies were examined, summarized, and grouped according to the type of strategy implemented. Effect sizes (ES) were calculated for each study. Across all studies, a mean ES of .78 was obtained, indicating a moderate positive effect on students with LD science achievement. Findings also align with past reviews of inquiry‐based instruction for students with special needs, indicating that students with LD need structure within an inquiry science approach in order to be successful. Additionally, results suggest that mnemonic instruction is highly effective at increasing learning disabled students' acquisition and retention of science facts. 相似文献
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Comparison of oil and egg tempera paint systems using time-of-flight secondary ion mass spectrometry
Zachary E. Voras Kristin deGhetaldi Brian Baade Eric Gordon Glenn Gates Thomas P. Beebe 《文物保护研究》2016,61(4):222-235
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni. 相似文献