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31.
In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure. 相似文献
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Educational Psychology Review - The purpose of this systematic review is to describe the state of the art of sequential multiple-assignment randomized trials in education research. An iterative,... 相似文献
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Erin R. Ottmar Lauren E. Decker Claire E. Cameron Timothy W. Curby Sara E. Rimm-Kaufman 《Learning Environments Research》2014,17(2):243-262
This study examined the quality of teacher–child interactions and exposure to mathematics instruction as predictors of 5th grade student’s mathematics achievement. The sample was a subset of the children involved in the NICHD–SECC longitudinal study (N = 657). Results indicate that, even after controlling for student demographic characteristics, more exposure to mathematics instruction was related to increased fifth grade mathematics achievement for both calculations and applied problems assessments, but there was no main effect for improved instructional quality. Findings also indicate that, in classrooms where lower instructional quality was observed, greater exposure to mathematics instruction predicted improved mathematics achievement. Findings are discussed in terms of differing aspects of mathematics instruction and the possible compensatory role of exposure to instruction in classrooms of lower quality. 相似文献
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This article describes a half-day preconference that focused on the library as publisher. It examined how the movement from print to online publication has impacted the roles of libraries and their ability to take on new roles as publishers. The session explored the benefits of libraries becoming publishers, and discussed Open Access, what it is and is not and its importance to libraries and scholarly communication. A detailed case study of the publishing operations of the University Library System at the University of Pittsburgh was presented as an example of a successful library publishing program. The session provided an opportunity for participants to discover ways that libraries can be involved in publishing. 相似文献
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Neal RE Ajamie LF Harmon KD Kellerby CD Schweikhard AJ 《Medical reference services quarterly》2010,29(4):405-413
In planning for a new library construction project for the University of Oklahoma-Tulsa, graduate students enrolled in the University of Oklahoma (OU) School of Library and Information Studies collaborated in an innovative effort to develop a commons-based reference service. By first considering a philosophical approach to the need for a commons, blending in the experiences of other libraries that have created similar spaces, and focusing on the workflow issues likely to be encountered by the graduate assistants staffing the commons itself, this planning team developed an uncommon peer-to-peer approach to reference and education services, one focused on the patron as student. 相似文献
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Miller CJ Miller SR Bloom JS Jones L Lindstrom W Craggs J Garcia-Barrera M Semrud-Clikeman M Gilger JW Hynd GW 《Annals of dyslexia》2006,56(1):83-102
The double-deficit hypothesis of dyslexia posits that reading deficits are more severe in individuals with weaknesses in phonological awareness and rapid naming than in individuals with deficits in only one of these reading composite skills. In this study, the hypothesis was tested in an adult sample as a model of reading achievement. Participants were parents of children referred for evaluation of reading difficulties. Approximately half of all participants reported difficulty learning to read in childhood and a small subset demonstrated ongoing weaknesses in reading. Structural equation modeling results suggest that the double-deficit hypothesis is an accurate model for understanding adult reading achievement. Better reading achievement was associated with better phonological awareness and faster rapid automatized naming in adults. Posthoc analyses indicated that individuals with double deficits had significantly lower reading achievement than individuals with single deficits or no deficits. 相似文献
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