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J W Barry 《Bulletin of the Medical Library Association》1971,59(4):574-578
A new free-standing library building, designed to integrate the collections serving interdisciplinary study in science and medicine, is described. 相似文献
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Matthew J. Kennedy Harold D. Ladouceur Tiffany Moeller Dickson Kirui Carl A. Batt 《Biomicrofluidics》2012,6(4)
The present work describes the operation and simulation of a microfluidic laminar-flow mixer. Diffusive mixing takes place between a core solution containing lipids in ethanol and a sheath solution containing aqueous buffer, leading to self assembly of liposomes. Present device architecture hydrodynamically focuses the lipid solution into a cylindrical core positioned at the center of a microfluidic channel of 125 × 125-μm2 cross-section. Use of the device produces liposomes in the size range of 100–300 nm, with larger liposomes forming at greater ionic strength in the sheath solution and at lower lipid concentration in the core solution. Finite element simulations compute the concentration distributions of solutes at axial distances of greater than 100 channel widths. These simulations reduce computation time and enable computation at long axial distances by utilizing long hexahedral elements in the axial flow region and fine tetrahedral elements in the hydrodynamic focusing region. Present meshing technique is generally useful for simulation of long microfluidic channels and is fully implementable using comsol Multiphysics. Confocal microscopy provides experimental validation of the simulations using fluorescent solutions containing fluorescein or enhanced green fluorescent protein. 相似文献
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We investigated relationships between the learning environment and students’ mathematics anxiety, as well as differences between the sexes in perceptions of learning environment and anxiety. A sample of 745 high-school students in 34 different mathematics classrooms in four high schools in Southern California was used to cross-validate the What Is Happening In this Class? (WIHIC) learning environment instrument, together with an updated Revised Mathematics Anxiety Rating scale. Mathematics anxiety was found to have two factorially-distinct dimensions (namely, learning mathematics anxiety and mathematics evaluation anxiety) which yielded different patterns of results for sex differences and anxiety–environment associations. Relative to males, females perceived a more positive classroom environment and more anxiety about mathematics evaluation, but less anxiety about mathematics learning. Some statistically significant associations were found between anxiety and learning environment scales for learning mathematics anxiety but not for mathematics evaluation anxiety. 相似文献
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We investigated relationships between students’ perceptions of parental involvement in schooling, their Spanish classroom environment and student outcomes (attitudes and achievement). Modified Spanish versions of the What Is Happening In this Class?, Test of Spanish-Related Attitudes-L1, a parental involvement questionnaire and a Spanish achievement test were administered to 223 Hispanic Grade 4–6 students in South Florida. The factor structure and internal consistency reliability of the questionnaires was supported. Strong associations were found for parental involvement with students’ learning environment perceptions and student outcomes, and for Spanish classroom environment with student outcomes. When the unique and common variances in student outcomes explained by the classroom environment and the home environment were examined, the home environment was more influential than the classroom environment in terms of students’ attitudes, but the classroom environment was more influential than the home environment in terms of achievement. 相似文献
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