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991.
Berninger VW Abbott RD Zook D Ogier S Lemos-Britton Z Brooksher R 《Journal of learning disabilities》1999,32(6):491-503
Forty-eight children referred by teachers at the end of first grade for difficulty in reading were randomly assigned to three treatments, all of which modeled connections between written and spoken words but did not teach phonics rules, for eight half-hour individual tutoring sessions. The children were taught 48 words of varying orders of spelling-sound predictability (Venezky, 1995) using a whole-word method, for making connections between a word's name and its constituent letters; a subword method, for making connections between each color-coded spelling unit and its corresponding phonemes; or a combined whole-word and subword method. Regardless of the method used, children improved reliably on standardized reading measures and the taught words, showing that they could make connections between written and spoken words at the whole word and subword levels, even when rules were not taught. By posttest, the subword method showed a reliable advantage on a standardized test of real word reading. Knowledge of sounds associated with both multiletter and single-letter spelling units predicted reading achievement. Order of spelling-sound predictability (easy, moderate, difficult) was correlated with standardized measures of reading at pretest and posttest, and the magnitude of the relationship increased as a result of the intervention. Individual differences in verbal intelligence, rapid automatized naming, and phonological and orthographic skills predicted response to the intervention. Instructional implications of the results are discussed. 相似文献
992.
This article explores how students who are deaf and their instructors experience mainstream college classes. Both quantitative and qualitative procedures were used to examine student access to information and their sense of belonging and engagement in learning. Instructors were asked to discuss their approach to teaching and any instructional modifications made to address the needs of deaf learners. Results indicate that deaf students viewed classroom communication and engagement in a similar manner as their hearing peers. Deaf students were more concerned about the pace of instruction and did not feel as much a part of the 'university family' as did their hearing peers. Faculty generally indicated that they made few if any modifications for deaf students and saw support service faculty as responsible for the success or failure of these students. We discuss results of these and additional findings with regard to barriers to equal access and strategies for overcoming these barriers. 相似文献
993.
Walter P. Vispoel Thomas R. Rocklin Tianyou Wang Timothy Bleiler 《Journal of Educational Measurement》1999,36(2):141-157
Part of the controversy about allowing examinees to review and change answers to previous items on computerized adaptive tests (CATs) centers on a strategy for obtaining positively biased ability estimates attributed to Wainer (1993) in which examinees intentionally answer items incorrectly before review and to the best of their abilities upon review. Our results, based on both simulated and live testing data, showed that there were instances in which the Wainer strategy yielded inflated ability estimates as well as instances in which it yielded deflated ability estimates. The success of the strategy in inflating ability estimates depended on the ability estimation method used (maximum likelihood versus Bayesian), the examinee's true ability level, the standard error of the ability estimate, the examinee's ability to implement the strategy, and the type of decision made from the ability estimate. We discuss approaches to dealing with the Wainer strategy in operational CAT settings. 相似文献
994.
Gavan P. McNally Marika C. Gorrisen Lee-fay Low R. Frederick Westbrook 《Learning & behavior》1999,27(4):416-425
Rats were used in four experiments to study the effects on behavior and pain sensitivity of exposure to a context previously
paired with footshock or injection of the emetic drug lithium chloride (LiCl). Exposure to a context previously paired with
footshock or injection of LiCl provoked the species-typical defense response of freezing (Experiments 1A and 1B). Exposure
to a context previously paired with footshock additionally produced hypoalgesia when rats were tested using the tailflick
test (Experiment 1A). By contrast, exposure to a context previously paired with injection of LiCl produced hyperalgesia when
rats were tested using the tailflick test (Experiment 1B). However, exposure to a context previously paired with injection
of LiCl did provoke hypoalgesia when rats were tested for pain sensitivity using either the hotplate or formalin tests (Experiment
2), which was mediated by the release of endogenous opioid peptides (Experiment 3). These results are discussed with reference
to the processes governing associative regulation of defensive behavior and pain control. 相似文献
995.
Physiological effects of infant exposure to environmental tobacco smoke: a passive observation study
This study explored infant physiologic responses of exposure to environmental tobacco smoke (ETS) using a longitudinal passive observation study with a control group. Fifteen smoking and 15 non-smoking mothers were initially contacted in hospital maternity units, with home visits made when their infants were 2, 4, and 6 weeks old. Exposure to ETS was measured using infant urinary nicotine and cotinine levels. The physiologic effects of infant ETS exposure were measured by rectal temperature, pulse rate, respiratory rate, blood pressure, and oxygen saturation. The smoking mothers in this sample were poorer, had less education, and were less likely to be married than the mothers who did not smoke. At birth, the infants of smoking mothers had higher diastolic blood pressure than infants of non-smoking mothers (p < .008). Mothers who smoke cigarettes should be educated that maternal smoking behavior can affect an infant's cardiovascular function. Parents should also be counseled about the risks of smoking in close proximity and/or in an enclosed space with an infant, especially in a motor vehicle. 相似文献
996.
This case study illustrates instruction in an urban 6th‐grade classroom in which students were learning about mass, volume, and density by attempting to layer (stack) three miscible solutions with differing densities atop one another. The study examines classroom discourse and interaction on the basis of four teaching goals: (a) reaching consensus about which stacks were possible, (b) developing persuasive arguments that separated data from noise, (c) establishing social norms for collective inquiry, and (d) appreciating the epistemological status of scientific knowledge. The study traces the fate of three stacks that students claimed were possible after initial investigations with the solutions. These claims underwent a process of collective validation in which consensus without coercion was the goal, which illustrates emergent standards for backing claims with evidence, as well as for replicability, among the students. Students were successful in achieving three of the four goals, with some qualifications. In relation to Goal 3, which required generalization to other situations, somewhat less success is reported. Limitations in the current standards, difficulties of time allotment in current curricula, and establishing classroom cultures of inquiry are discussed. © 1999 John Wiley & Sons, Inc. J Res Sci Teach 36: 179–199, 1999 相似文献
997.
Michael R. Jolley Emily Cross Miles Bryant 《Community College Journal of Research & Practice》2014,38(2-3):218-230
In 2011, according to a National Center for Education Statistics report, part-time instructional staff in all higher education institutions exceeded full-time faculty members for the first time, accounting for 50% of all instructional staff (National Center for Education Statistics [NCES], 2012). The same report indicates part-time faculty in community colleges exceeds 70% of instructional staff. Perhaps more alarming are the numbers of contingent instructional staff—faculty without long-term employment commitments. According to this measure, nearly 70% of faculty members in all areas of higher education have little-to-no job stability (American Association of University Professors [AAUP], 2013; Schuster & Finklestein, 2006). However, limited research exists on the working experiences of this major subpopulation of United States professors. The purpose of this qualitative study was to explore the experiences of part-time contingent community college faculty regarding the assessment processes their institutions implemented. Through interviews, researchers gathered data identifying what 20 part-time contingent faculty professors reported regarding teaching conditions and institutional assessment procedures. Participant interviews revealed two major themes centered on a lack of institutional engagement and meaningful assessment policies or procedures. 相似文献
998.
S. Negassi 《Research Policy》2004,33(3):365-384
The scope of this paper is to report new empirical evidence on the determinants of R&D co-operation. Indeed, the literature on the capabilities of firms emphasises the role of knowledge in the performance and evolution of firms who use knowledge developed in others to build their own knowledge capital. R&D co-operation between firms is one of the many strategies by which this knowledge may be transmitted. Several theoretical models have stressed that R&D co-operation is more likely when the level of spillovers is high. While this supposition is used in many theoretical models, it has rarely been tested before. Our results do not lend strong support to this intuition. Indeed, our spillover variables (national pure spillovers, national rent spillovers and imports of machine tools), which were supposed to match the theoretical notion of spillovers used in these theoretical models have a positive but not a significant role when explaining R&D co-operation. The R&D co-operation increases with size and with R&D intensity, but not with market share. It also increases with the budget spent on paying license fees and on acquiring patents and labour from foreign firms. In this study, we also analyse the determinants of innovation. In more precise terms, we compare the effects of R&D co-operation to those played by traditional internal factors and those exerted by external, pure and rent spillovers on the innovation capacity of the firms. Our results show that the commercial success of innovations of French firms depends mainly on size, market share, R&D intensity and human capital. Inward FDI from industrialised countries exerts a positive and significant effect. The finding highlights the important role of the absorptive capacity of firms. Spillover measurements, such as the acquisition of machine tools, foreign patents, licenses, and technological opportunities have a positive impact on innovation. 相似文献
999.
R. Kumar R. Kapoor B. Mittal A. Kumar R. D. Mittal 《Indian journal of clinical biochemistry : IJCB》2003,18(2):209-215
Metabolic abnormalities were investigated in 44 stone patients with first time (group 1) and 56 with 2 times stone formation
(group 2), and in 25 normal individuals. 24hr urine was analysed spectrophotometrically for oxalate, calcium, magnesium, citrate,
uric acid, phosphate and creatinine. Hypocitraturia and hyperoxaluria were the common abnormalities in the stone formers.
Stone patients had significantly higher urinary oxalate, calcium and uric acid and lower phosphate than normal individuals.
Citrate/calcium and magnesium/calcium ratio were significantly high in normal individuals than stone formers. Patients in
group 2 excreted significantly higher urinary calcium and lower citrate that patients in group 1. Citrate/calcium ratio was
higher in group 1 than group 2. Hypocitraturia, hyperoxaluria, hypercalciuria and increased citrate/calcium and magnesium/calcium
ratio seem to be an essential risk factor for stone formation. Patients with recurrent stone formation could be distinguished
from patients with first time stone formation on the basis of urinary calcium and citrate. 相似文献
1000.