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921.
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
922.
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
923.
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
924.
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
925.
926.
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
927.
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
928.
929.
Dra?an Butorac Ivana ?elap Sanja Ka?kov Vera Robi? Tomislav Mileti? Zlata Flegar Me?tri? Andrea Hulina Krunoslav Kuna Tihana ?ani? Grubi?i? Marija Grdi? Rajkovi? 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(2):273-280
Introduction
Postmenopausal women have higher risk of cardiovascular disease. One of the contributing factors could be reduced activity of anti-atherogenic enzyme paraoxonase 1 (PON1). The aim of this study was to examine differences in the lipid status, paraoxonase and arylesterase PON1 activities and PON1 phenotype in women with regular menstrual cycle and in postmenopausal women.Materials and methods:
The study included 51 women in reproductive age (25 in follicular and 26 in luteal phase of the menstrual cycle) and 23 women in postmenopause. Lipid parameters in sera were determined using original reagents and according to manufacturer protocol. PON1 activity in serum was assessed by spectrophotometric method with substrates: paraoxon and phenylacetate. PON1 phenotype was determined by double substrate method.Results:
Compared to the women in follicular and luteal phase, postmenopausal women have significantly higher concentration of triglyceride [0.9 (0.7–1.3), 0.7 (0.6–1.0) vs. 1.5 (0.9–1.7) mmol/L; P = 0.002], cholesterol [5.10 (4.78–6.10), 5.05 (4.70–5.40) vs. 6.30 (5.73–7.23) mmol/L; P < 0.001], LDL [3.00 (2.56–3.63), 3.00 (2.70–3.70) vs. 3.90 (3.23–4.50) mmol/L; P < 0.001], and apolipoprotein B [0.88 (0.75–1.00), 0.79 (0.68–1.00) vs. 1.07 (0.90–1.24) mmol/L; P = 0.002]. PON1 basal [104 (66–260), 106 (63–250) vs. 93 (71–165) U/L; P = 0.847] and salt-stimulated paraoxonase activity [210 (131–462), 211 (120–442) vs. 180 (139–296) U/L; P = 0.857] as well as arylesterase activity [74 (63–82), 70 (54–91) vs. 70 (60–81) kU/L; P = 0.906] and PON1 phenotype (P = 0.810) were not different in the study groups.Conclusion:
There are no differences in PON1 activity and PON1 phenotype between women with regular menstrual cycle and postmenopausal women. 相似文献930.
We analyse how the impact of determinants of inter-firm knowledge transfers in alliances can be moderated by the proximity of the resources pooled by partners. Six factors are examined: relative absorptive capacity (RAC), inter-partner trust, cultural distance between allies, knowledge ambiguity, knowledge protection, and the partners’ learning intent. We distinguish alliances mobilizing similar resources by partners (called ‘endogamies’ as allies build on their similarities) from alliances pooling different resources (called ‘exogamies’ as allies build on their differences). We propose that: (a) the impact of RAC on knowledge transfers is reinforced in exogamies, but reduced in endogamies; (b) the knowledge ambiguity and cultural distance effect is less in endogamies than in exogamies; (c) the trust and knowledge protection impact is stronger in exogamies than in endogamies; (d) the learning intent impact on knowledge transfers is similar in endogamies and exogamies. 相似文献