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941.
Carolina?TinajeroEmail author Zeltia?Martínez-López Ma?Soledad?Rodríguez Ma?Adelina?Guisande Ma?Fernanda?Páramo 《European Journal of Psychology of Education - EJPE》2015,30(2):227-244
Perceived social support has been shown to be one of the most important protective factors for emerging adult students during their transition to university. However, the relationships between perceived social support and dimensions of gender and family background, which have been shown to affect adjustment to college life, remain unexplored. The current study analyzes the effect of gender, parents’ education, and family income level on social support perceived by Spanish university students. The sample consisted of 575 women and 280 men, of average age 18.02 years (SD?=?0.52) enrolled in the first year of degree courses at the University of Santiago de Compostela (Spain). Three measures were used to assess various facets of perceived social support, namely perceived acceptance, social provisions, and support availability and satisfaction. Gender differences were identified for several perceived social support dimensions; women reported a wider social network, which should cover more diverse needs of social support. In addition, differences related to mother’s education and family income level emerged for the availability of support and perceived acceptance. The results highlight the different role of gender and family background in several dimensions of perceived social support during the transition to emerging adulthood. 相似文献
942.
943.
An essay discussing the challenges and opportunities in global publishing and in particular the are addressing many of the big questions publishers are facing today which arise from the marriage of content and technology. Includes examination of three major verticals (STM, Education and Trade publishing) and considers the possibilities offered by cross-industry collaboration to evolve global standards. 相似文献
944.
This study investigates the undergraduates of a university in northern Taiwan for their reading habits and evaluation of Chinese translated books. It is found that reading translated books is prevalent among them. Their experiences of reading Chinese translated books tend to be satisfactory and more than half of them think the quality of Chinese translated books is fine. The result of this study confirms previous research that accuracy is the basic requirement of translated books and translation mistakes should be avoided, but goes against the popular perception that the quality of Chinese translated books in Taiwan is poor. 相似文献
945.
Lisa Sprenger Silvio Dutz Thomas Schneider Stefan Odenbach Urs O. H?feli 《Biomicrofluidics》2015,9(4)
Microfluidic spirals were used to successfully separate rare solid components from unpretreated human whole blood samples. The measured separation ratio of the spirals is the factor by which the concentration of the rare component is increased due to the Dean effect present in a flow profile in a curved duct. Different rates of dilution of the blood samples with a phosphate-buffered solution were investigated. The diameters of the spherical particles to separate ranged from 2 μm to 18 μm. It was found that diluting the blood to 20% is optimal leading to a separation ratio up to 1.97. Using two spirals continuously placed in a row led to an increase in separation efficacy in samples consisting of phosphate-buffered solution only from 1.86 to 3.79. Numerical investigations were carried out to display the flow profiles of Newtonian water samples and the shear-thinning blood samples in the cross-section of the experimentally handled channels. A macroscopic difference in velocity between the two rheologically different fluids could not be found. The macroscopic Dean flow is equally present and useful to help particles migrate to certain equilibrium positions in blood as well as lower viscous Newtonian fluids. The investigations highlight the potential for using highly concentrated, very heterogeneous, and non-Newtonian fluidic systems in known microsystems for screening applications. 相似文献
946.
Julien Marchalot Jean-Fran?ois Chateaux Magalie Faivre Hichem C. Mertani Rosaria Ferrigno Anne-Laure Deman 《Biomicrofluidics》2015,9(5)
Enrichment of rare cell populations such as Circulating Tumor Cells (CTCs) is a critical step before performing analysis. This paper presents a polymeric microfluidic device with integrated thick Carbon-PolyDimethylSiloxane composite (C-PDMS) electrodes designed to carry out dielectrophoretic (DEP) trapping of low abundance biological cells. Such conductive composite material presents advantages over metallic structures. Indeed, as it combines properties of both the matrix and doping particles, C-PDMS allows the easy and fast integration of conductive microstructures using a soft-lithography approach while preserving O2 plasma bonding properties of PDMS substrate and avoiding a cumbersome alignment procedure. Here, we first performed numerical simulations to demonstrate the advantage of such thick C-PDMS electrodes over a coplanar electrode configuration. It is well established that dielectrophoretic force (FDEP) decreases quickly as the distance from the electrode surface increases resulting in coplanar configuration to a low trapping efficiency at high flow rate. Here, we showed quantitatively that by using electrodes as thick as a microchannel height, it is possible to extend the DEP force influence in the whole volume of the channel compared to coplanar electrode configuration and maintaining high trapping efficiency while increasing the throughput. This model was then used to numerically optimize a thick C-PDMS electrode configuration in terms of trapping efficiency. Then, optimized microfluidic configurations were fabricated and tested at various flow rates for the trapping of MDA-MB-231 breast cancer cell line. We reached trapping efficiencies of 97% at 20 μl/h and 78.7% at 80 μl/h, for 100 μm thick electrodes. Finally, we applied our device to the separation and localized trapping of CTCs (MDA-MB-231) from a red blood cells sample (concentration ratio of 1:10). 相似文献
947.
Both fuzzy temporal constraint and flexible resource constraint are considered in project scheduling. Inorder to obtain an optimal schedule, we propose a genetic algorithm integrated with concepts on fuzzy set theory aswell as specialized coding and decoding mechanism. An example demonstrates that the proposed approach can assistthe project managers to obtain the optimal schedule effectively and make the correct decision on skill training before aproject begins. 相似文献
948.
Jamie?L.?JensenEmail author Mark?A.?McDaniel Steven?M.?Woodard Tyler?A.?Kummer 《Educational Psychology Review》2014,26(2):307-329
In order to test the effect of exam-question level on fostering student conceptual understanding, low-level and high-level quizzes and exams were administered in two sections of an introductory biology course. Each section was taught in a high-level inquiry based style but was assigned either low-level questions (memory oriented) on the quizzes and exams, or high-level questions (application, evaluation, and analysis) on the quizzes and exams for the entirety of the semester. A final exam consisting of 20 low-level and 21 high-level questions was given to both sections. We considered several theoretical perspectives based on testing effect, test expectancy, and transfer-appropriate processing literature as well as the theoretical underpinnings of Bloom’s taxonomy. Reasoning from these theoretical perspectives, we predicted that high-level exams would encourage not only deeper processing of the information by students in preparation for the exam but also better memory for the core information (learned in the service of preparing for high-level questions). Results confirmed this prediction, with students in the high-level exam condition demonstrating higher performance on both the low-level final-exam items and the high-level final exam items. This pattern suggests that students who are tested throughout the semester with high-level questions acquire deep conceptual understanding of the material and better memory for the course information, and lends support to the proposed hierarchical nature of Bloom’s taxonomy. 相似文献
949.
Douglas?D.?Agyei Jared?KeengweEmail author 《Education and Information Technologies》2014,19(1):155-171
This paper describes an intervention in which pre-service teachers developed their TPACK through multiple data sources. Teachers’ self-reports of their TPACK knowledge were triangulated with performance-based assessment of their instructional practices and artifacts to give a better understanding and nature of pre-service teachers’ TPACK development. Although self reported measures did not correlate with pre-service teachers’ actual increased knowledge of technology integration, this study enhances better understanding of the pre-service teachers’ TPACK development through the multiple assessment measures. The learning outcome measures provide specific information and concrete representation of what pre-service teachers can actually do with technology in their TPACK development. The findings suggested multiple concerns about self-reported measures that are discussed in the framework of the TPACK instrument. 相似文献
950.