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1.
Sovichea Lay Hai-ning Yu Bao-xiang Hu Sheng-rong Shen 《Journal of Zhejiang University. Science. B》2016,17(6):465-475
A pre-treatment methodology for clenbuterol hydrochloride (CLEN) isolation and enrichment in a complex matrix environment was developed through exploiting molecularly imprinted polymers (MIPs). CLEN-imprinted polymers were synthesized by the combined use of ally-β-cyclodextrin (ally-β-CD) and methacrylic acid (MAA), allyl-β-CD and acrylonitrile (AN), and allyl-β-CD and methyl methacrylate (MMA) as the binary functional monomers. MAA-linked allyl-β-CD MIPs (M-MAA) were characterized by Fourier transform-infrared (FT-IR) spectroscopy and a scanning electron microscope (SEM). Based upon the results, M-MAA polymers generally proved to be an excellent selective extraction compared to its references: AN-linked allyl-β-CD MIPs (M-AN) and MMA-linked allyl-β-CD MIPs (M-MMA). M-MAA polymers were eventually chosen to run through a molecularly imprinted solid-phase extraction (MISPE) micro-column to enrich CLEN residues spiked in pig livers. A high recovery was achieved, ranging from 91.03% to 96.76% with relative standard deviation (RSD) ≤4.45%. 相似文献
2.
The measurement of teachers' workload has till now been subjective. Teachers feel that they have a great responsibility to their pupils and to society and their workload heavy, while non-teachers may have different views. This debate occurs even amongst teachers teaching different subjects and levels in a school as well as amongst teachers in different schools. A comparison of teachers' workload in different countries is also particularly difficult because of different class sizes, curriculum time, etc. It is therefore essential to provide a quantitative and objective measure for evaluating teachers' workload. This measure can then be used as a reference by school principals when allocating extra duties to teachers. It is also useful to education authorities when deploying teachers to various schools in centralized education systems. 相似文献
3.
Lay Hoon Seah 《International Journal of Science and Mathematics Education》2016,14(6):1059-1078
Although the importance of language in science learning has been widely recognized by researchers, there is limited research on how science teachers perceive the roles that language plays in science classrooms. As part of an intervention design project that aimed to enhance teachers’ capacity to address the language demands of science, interview data (N = 9) were collected to understand teachers’ perceptions and experiences with a wide range of issues related to language use in science classrooms. Adopting an interpretive approach to qualitative data, the analysis revealed that the teachers perceive a wide range of student difficulties related to language use in science classrooms, especially to the use of specialized terms and writing. Although the teachers are keenly aware of how language can be a barrier to learning science, they are less certain as to what students need to know about the language of science in order to master it. The findings suggested professional support that highlights the distinctive language demands of science and how these demands differ from other subject areas could be useful to these elementary school teachers. 相似文献
4.
Magana Alejandra J. Elluri Sindhura Dasgupta Chandan Seah Ying Ying Madamanchi Aasakiran Boutin Mireille 《Journal of Science Education and Technology》2019,28(4):382-398
Journal of Science Education and Technology - In science and engineering education, the use of heuristics has been introduced as a way of understanding the world, and as a way to approach... 相似文献
5.
Chng Huang Hoon Joy Mighty Torgny Roxå Mary Deane Sorcinelli 《International Journal for Academic Development》2019,24(2):97-108
ABSTRACTWhat role does academic development have to play in responding to radical cultural shifts in the global landscape? Whose voices and identities are contributing to institutional change? This reflective essay encompasses the perspectives of the four international panellists in the opening plenary of the International Consortium for Educational Development (ICED) 2018 conference in Atlanta, Georgia, USA – Torgny Roxå on ideologies; Chng Huang Hoon on agency and empowerment; Joy Mighty on voices and identities; and Mary Deane Sorcinelli on evidence and outcomes. These perspectives set the stage for the conference, and, brought together in this paper now, they address key conference themes, offer coordinates for reflection, and pose further questions about our profession. 相似文献
6.
In this paper, the quadratic minimax optimal control of linear system with input-dependent uncertainty is studied. We show that it admits a unique solution and can be approximated by a sequence of finite-dimensional minimax optimal parameter selection problems. These finite-dimensional minimax optimal parameter selection problems are further reduced to scalar optimization problems which also admit unique solutions. Thus, the original minimax optimal control problem is solved via solving a sequence of simple scalar optimization problems. Numerical experiments are presented to illustrate the developed method. 相似文献
7.
This paper reports a method to control the fluid flow in paper-based microfluidic devices simply by pressing over the channel surface of paper, thereby decreasing the pore size and permeability of a non-woven polypropylene sheet. As a result, fluid resistance is increased in the pressed region and causes flow rate to decrease. We characterize the decrease of flow rate with respect to different amounts of pressure applied, and up to 740% decrease in flow velocity was achieved. In addition, we demonstrate flow rate control in a Y-shaped merging paper and sequential delivery of multiple color dyes in a three-branched paper. Furthermore, sequential delivery of multiple fluid samples is performed to demonstrate its application in multi-step colorimetric immunoassay, which shows a 4.3-fold signal increase via enhancement step. 相似文献
8.
Myint Swe Khine Lay Leng Yeap Anthony Tan Chin Lok 《Educational Media International》2013,50(1-2):115-126
One of the major shifts in education today under the influence of information and communication technologies is that there is an increased tendency toward the use of computer-mediated communications (CMC). CMC has developed an assortment of methods from simple e-mail to wireless instant messages and synchronous and asynchronous discussions. A large portion of the research in this area focuses on the pedagogical aspects of CMC particularly on the use, strategies, effectiveness and the integration of the new technologies for teaching and learning. Some studies investigate different perspectives of interaction like keeping track of asynchronous discussion, quality of participation, interaction and collaborative or group learning. This paper reports findings from the study that examines the quality of message ideas, thinking and interaction in an asynchronous CMC environment in a teacher training institution. The authors suggest some practical strategies in the implementation of asynchronous discussions in CMC environment. La qualité des messages d’idées, de la pensée et de l’interaction dans un environnement CMC asynchrone. Un des changements majeurs dans l’éducation aujourd’hui sous l’influence de l’information et des technologies de la communication est une tendance accrue À l’usage des communications par ordinateur (Computer-mediated Communications CMC). CMC a permis le développement de tout un assortiment de méthodes depuis de simples e-mail jusqu’À des messages sans fil instantanés et des discussions synchrones et asynchrones. Une grande partie de la recherche en ce domaine est centrée sur les aspects pédagogiques des CMC en particulier sur l’emploi, les stratégies, l’efficacité et l’intégration des nouvelles technologies pour l’enseignement et l’apprentissage. Certains études examinent les perspectives différentes de l’interaction. Telles que garder la trace des discussions asynchrones, la qualité de la participation interaction et l’apprentissage en coopération ou en groupe. L’article rapporte les résultats de l’étude qui examine la qualité des messages d’idées, la pensée et l’interaction dans un environnement de CMC asynchrone dans un établissement de formation des enseignants. Les auteurs suggérent des stratégies pratiques dans l’introduction de discussions asynchrones dans un environnement CMC. Die Qualität der übermittlung von Ideen, Denken und Interaktion in einem asynchronen CMC Umfeld Eine der wichtigsten Umstellungen der heutigen Ausbildung ist die unter dem Einfluss von Informations- und Kommunikationstechnologien verstärkte Tendenz, rechnergestützte Kommunikation (computer-mediated communications:CMC) zu benutzen. CMC hat ein ganzes Arsenal von Methoden entwickelt, von der einfachen E-Mail bis zu drahtlosen Nachrichten und synchron oder asynchron geführten Diskussionen. Die Forschung in diesem Bereich konzentriert sich hauptsächlich auf die pädagogischen Aspekte von CMC, besonders auf die Nutzung, die Strategien, den Wirkungsgrad und die Möglichkeiten der Einbindung der Neuen Technologien zum Lehren und Lernen. Einige Arbeiten erforschen die verschiedenen Perspektiven der Interaktion wie das Verfolgen von asynchronen Diskussionen, die Qualität der Beteiligung, der Interaktion und Zusammenarbeit oder dem Lernen in Gruppen. In diesem Beitrag wird über Ergebnisse der Studie zur Untersuchung der Qualität der übermittlung von Ideen, Gedanken und Interaktionen in einem asynchron arbeitenden rechnergestützten System (CMC) einer Lehrerfortbildungseinrichtung berichtet. Die Autoren erläutern praktische Strategien zur Einbindung asynchroner Diskussionen in eine CMC-Umgebung. 相似文献
9.
Research Findings: This study explored the association between the home literacy environment (HLE), conceptualized as comprising parents’ reading beliefs and home literacy practices, and preschoolers’ reading skills and reading interest. It also identified factors in the HLE that predict emerging reading competence and motivation to read. A total of 193 children age 6 years from 14 preschools across Singapore and their parents participated in the study. The parents completed a reading belief inventory, a family literacy activity inventory, and a demographic questionnaire that surveyed the child's reading interest. The children were administered a battery of standardized literacy tests. The study found a moderate relationship between the HLE and children's reading competencies and a strong relationship between the HLE and children's reading interest. When parents’ education level and children's age were controlled, hierarchical multiple regression analyses found that family literacy activities contributed more unique variance to children's reading outcomes and reading interest than did parents’ reading beliefs. Active parental involvement was the strongest component of the HLE, with parent–child engagement in reading and writing emerging as the best predictor of both the child's emerging reading skills and reading interest. With respect to reading beliefs, parents’ efficacy in supporting literacy development before their child attended school positively predicted reading competence, as did parents’ affect and verbal participation in fostering reading interest. However, verbal participation negatively predicted Singapore children's reading competence. Practice or Policy: The implications of the results were discussed. 相似文献
10.
Kwon YH Como CS Singhal K Lee S Han KH 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(2):127-148
The purposes of this study were (1) to determine the functional swing plane (FSP) of the clubhead and the motion planes (MPs) of the shoulder/arm points and (2) to assess planarity of the golf swing based on the FSP and the MPs. The swing motions of 14 male skilled golfers (mean handicap = -0.5 +/- 2.0) using three different clubs (driver, 5-iron, and pitching wedge) were captured by an optical motion capture system (250Hz). The FSP and MPs along with their slope/relative inclination and direction/direction of inclination were obtained using a new trajectory-plane fitting method. The slope and direction of the FSP revealed a significant club effect (p < 0.001). The relative inclination and direction of inclination of the MP showed significant point (p < 0.001) and club (p < 0.001) effects and interaction (p < 0.001). Maximum deviations of the points from the FSP revealed a significant point effect (p < 0.001) and point-club interaction (p < 0.001). It was concluded that skilled golfers exhibited well-defined and consistent FSP and MPs, and the shoulder/arm points moved on vastly different MPs and exhibited large deviations from the FSP. Skilled golfers in general exhibited semi-planar downswings with two distinct phases: a transition phase and a planar execution phase. 相似文献