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101.
102.
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
103.
Chinese students at an English-Language university: Prediction of academic performance 总被引:1,自引:0,他引:1
There is a paucity of systematic research on prediction of success at the tertiary education level for Asian students, despite the important role that universities play in Asian communities, and despite the increasing numbers of such students who are coming to the West to study. This study reviews evidence collected over the past ten to fifteen years, which relates to the issue of prediction of academic performance of Chinese students at an English-Language and Western-oriented university - the University of Hong Kong. This review is complemented by an analysis of data collected longitudinally over a five year period, using multiple regression, multiple correlation, path analysis and canonical correlation analyses. The results provide evidence of factors which are important in determining the ability of a student to adapt to the foreign cultural and language barriers that exist at this university. In particular, ability in English language and mathematics provides good and reasonably independent predictors of success. The data show the importance of considering the cultural background of students when assessing their aptitude for study, and offer information for Western universities regarding their admissions procedures for Chinese students. 相似文献
104.
Dagmar Sigmundová Petr Badura Erik Sigmund Jens Bucksch 《European Journal of Sport Science》2018,18(8):1158-1167
This study assessed the associations between these factors in a random sample of Czech families with preschool and school-aged children. A nationally representative sample comprised 185 families with preschool children and 649 families with school-aged children (dyads; both parents and child n?=?365, mother and child n?=?730, and father and child n?=?469). The participants wore Yamax Digiwalker SW-200 pedometers at least four weekdays and both weekend days and completed family logbooks (anthropometric parameters, daily step counts (SC), and screen time (ST)). When a parent (fathers at weekends and mothers both on weekdays and at weekends) achieved 10,000 SC per day, their children were also significantly (OR?=?2.93–6.06, 95% CI?=?2.02–9.26) more likely to meet the daily SC recommendation. On the contrary, the involvement of fathers in organized leisure-time PA reduced their children's odds of meeting the SC recommendation on weekdays (OR?=?0.53, 95% CI?=?0.31–0.89) and at weekends (OR?=?0.41, 95% CI?=?0.24–0.72). The excessive ST of parents at weekends reduced the odds of their children meeting the SC recommendation (mother–child dyads: OR?=?0.44, 95% CI?=?0.26–0.72; father–child dyads: OR?=?0.63, 95% CI?=?0.37–1.06). High levels of parents’ PA contribute to the achievement of the recommended daily PA in children on weekdays and at weekends. Excessive weekend ST of parents reduces their odds of their children achieving the recommended daily PA; however, the influence of parents’ PA on their children’s achieving the recommended daily PA is stronger than the inhibitory effect of ST. 相似文献
105.
Fu-Ming Chen Jason Sheng-Hong Tsai Ying-Ting Liao Shu-Mei Guo Ming-Chung Ho Fu-Zen Shaw Leang-San Shieh 《Journal of The Franklin Institute》2014
An improvement on the transient response of tracking for the sampled-data system based on an improved PD-type iterative learning control (ILC) is proposed in this paper. The developed analog ILC method and the high-gain property tracker design methodology are first combined to significantly reduce learning epochs and overcome the initial condition shift problem and discontinuous reference input in the traditional ILC. Besides, the proposed ILC improves the transient response and decreases the rate of weighting matrices Q to R under the traditional linear quadratic tracker design. First, the off-line observer/Kalman filter identification (OKID) is used to determine the appropriate (low-) order system parameters and state estimator for the physical system with unknown system equation, so that the model-based PD-type ILC can be implemented for practical applications. Then, to improve the transient response and decrease the control effort, the proportional difference type (PD-type) ILC algorithm is combined with the high-gain property linear quadratic tracker (LQT) design to construct the high performance tracker for the model-based sampled-data systems. Furthermore, the discrete-time version high performance tracker design for the unknown stochastic sampled-data system via the iterative learning control method is proposed in this paper based on the Euler method and the digital redesign approach. Finally, some examples are given for illustrating the effectiveness of the proposed method. 相似文献
106.
Wendell Arthur Lopes Neiva Leite Larissa Rosa da Silva Diego Trevisan Brunelli Arthur Fernandes Gáspari Rosana Bento Radominski 《Journal of sports sciences》2016,34(20):1902-1912
The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13–17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6–10 repetitions at 60–70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50–80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (P < 0.01) and increase in fat-free mass (P < 0.01), VO2peak (P < 0.01), 1 RM for leg press (P < 0.01) and bench press (P < 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (P < 0.05) and leptin (P < 0.05), as well as in insulin resistance (P < 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls. 相似文献
107.
Talis Tisenkopfs Ilona Kunda Sandra šūmane Gianluca Brunori Laurens Klerkx Heidrun Moschitz 《The Journal of Agricultural Education and Extension》2015,21(1):13-33
AbstractPurpose: The paper explores the role of boundary work and boundary objects in enhancing learning and innovation processes in hybrid multi-actor networks for sustainable agriculture (LINSA).Design/Methodology/Approach: Boundary work in LINSA is analysed on the basis of six case studies carried out in SOLINSA project under a common methodology. In developing typologies of boundary work and objects, a grounded approach is used.Findings: LINSA analysis demonstrates the dynamic character, diverse forms and multiple functions of boundary work and objects in three domains: learning, innovation, and sustainability. Addressing specific types of goals and actors leads to specific types of boundary work and boundary objects. Context-appropriate boundary work allows aligning differing actor attitudes, gaining increased external support, and developing LINSA. The concepts of boundary work and boundary objects are relevant in a broad range of divergent LINSA settings. Boundary work has its limitations, but its facilitation supports reaching LINSA goals.Practical Implications: The paper proposes recognising context-appropriate forms of boundary work and skilful use of emerging boundary objects to both promote internal consolidation of LINSA and effective external communication to foster learning and innovation for sustainability.Originality/Value: The paper provides insights into the forms, dynamic and outcomes of boundary work in LINSA in three key domains: developing shared knowledge base, co-producing innovation and negotiating sustainability. 相似文献
108.
Pedro Rosário José Carlos Núñez Luisa Trigo Carina Guimarães Estrella Fernández Rebeca Cerezo 《高等教育研究与发展》2015,34(1):173-187
The current investigation aims at assessing the effectiveness of an intervention program designed to enhance self-regulated learning (SRL) strategies at the university level, with students from different cultural, linguistic, and educational backgrounds. The central tool of the program is a set of letters in which a fictional first-year student describes his experiences as an SRL student. The program was implemented in four universities in different countries and continents (Portugal, Spain, Chile, and Mozambique), with an experimental group and a comparison group at each university (263 students from experimental groups and 247 from comparison groups). Findings display the effectiveness of the program in enhancing a set of motivational variables related to the study process and the use of SRL strategies. Data were consistent across the different cultural and academic contexts in which the program was implemented. The implications of these findings for university administrators and faculty are discussed. 相似文献
109.
László Kovács Jr 《Science & Education》1996,5(3):309-311
The present article is based on Zoltán Bay's Old Education, New Teaching — an unpublished paper written for the XXVIIth National Meeting of Secondary School Physics Teachers (5–7th April, 1984 Veszprém, Hungary). 相似文献
110.
Irene T. Ho 《教育心理学》2004,24(3):375-391
The present study compared Australian and Chinese teachers' causal attributions for student behavior. A total of 204 Australian teachers and 269 Chinese teachers rated the importance of four causes (ability, effort, family, teacher) of six student problem behaviors. Results showed that both groups of teachers attributed misbehaviors most to student effort and least to teacher factors. Chinese teachers emphasized family factors more while Australian teachers placed greater importance on ability. There was significant variation in attribution patterns for different types of problems, with effort attribution being equally and strongly emphasized across cultural contexts and behavior types. The results are interpreted in the light of how individualistic and collectivistic values influence teacher thinking, and implications for school‐based interventions for behavior problems are discussed. 相似文献