208 research outputs found

    Discovery-based Teaching Methodology: A Framework for Quality Teaching and Learning

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    The adoption of the standards-based model in the Moroccan EFL context entails an implementation of effective teaching methodologies which ensure the provision of excellent and equitable learning experiences for all learners. Discovery teaching is an example of a pedagogical model which focuses on the learner as an active member in the learning process. This pedagogical tool has been reported to be effective in assisting learners to understand difficult concepts and retain long term information. This literature-based article seeks to define discovery-based teaching method, discuss its added value in the teaching-learning process and illustrate its effectiveness on both teachers and learners. Previous research has shown the role of this pedagogical tool in promoting teacher effectiveness and thereby enhancing student learning. Based on this, the present article argues for the need to adopt this teaching method in different educational contexts as an effective style of instruction that can ensure quality teaching and learning

    Spherical activated carbons for the adsorption of a real multicomponent VOC mixture

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    The objective of this work is to study the adsorption of a multicomponent gaseous mixture (acetaldehyde, formaldehyde, 2-propenal, 1,3-butadiene and benzene) in which the components are present at different concentration on spherical activated carbons (SACs). Attention is paid to the influence of the carbons’ properties on such adsorption, especially their porosities and distributions. For this purpose, a series of spherical activated carbons were prepared by physical activation with CO2 of a commercial spherical carbon. Their physico-chemical properties were characterized by N2 and CO2 isotherms, temperature programmed desorption and scanning electron microscopy. Measurements of the adsorption of the volatile organic compounds (VOC) mixture on SACs were performed in a flow-typed fixed bed system at room temperature under atmospheric pressure. Regarding porosity, our results show that, for this particular mixture, SACs with narrow micropore size distribution and moderate porous texture development (surface area in the range of 1000 m2/g or even lower) exhibit higher multicomponent adsorption capacities than others with much larger porosities. This can be explained considering that the VOC present in larger concentration in the mixture, aldehydes, present low adsorption affinities and their adsorption is enhanced in adsorbents with narrow micropore size distribution.The authors would like to thank Philip Morris International (PMI) for financial support

    English Language Teacher Supervision in Morocco in the Context of Covid 19 and its Aftermath

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    The Coronavirus pandemic has affected education and triggered a number of debates relating to the plethora of online teaching and learning modes available. Debates focus mainly on the issues of training, challenges of implementation, and related impacts in the field of English language teaching and learning. Strong emphasis has been laid on the ways to improve teaching practices and boost student learning outcomes (Maher & Zollman, 2021; Mette, 2020). Teacher supervision in the Moroccan EFL context, however, is an area which has not received sufficient focus. In the context of the Coronavirus, ELT teacher supervisors have had to deal with new challenges and have been called upon to contribute to the community of teachers who have emerging in-service training needs and expectations and who are facing new challenges. The objective of this position paper is to discuss our experience of online teaching supervision with a specific focus on the emergent needs of teachers and to outline the ways we addressed these ongoing teacher professional development needs. The thrust of the argument is that despite the challenges that characterize online teacher supervision including lack of or limited ICT infrastructure, technological failures and digital literacy skills, online teacher supervision was largely a successful experience thanks to the convenience, flexibility and practicability of this online supervision mode. We specifically argue that collegiality and effective collaboration between and among ELT supervisors and teachers were key factors in the success of this undertaking. Implications are then drawn for more meaningful and transformative teaching and learning experiences in the future

    Xylosyltransferase-I Regulates Glycosaminoglycan Synthesis during the Pathogenic Process of Human Osteoarthritis

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    Loss of glycosaminoglycan (GAG) chains of proteoglycans (PGs) is an early event of osteoarthritis (OA) resulting in cartilage degradation that has been previously demonstrated in both huma and experimental OA models. However, the mechanism of GAG loss and the role of xylosyltransferase-I (XT-I) that initiates GAG biosynthesis onto PG molecules in the pathogenic process of human OA are unknown. In this study, we have characterized XT-I expression and activity together with GAG synthesis in human OA cartilage obtained from different regions of the same joint, defined as “normal”, “late-stage” or adjacent to “late-stage”. The results showed that GAG synthesis and content increased in cartilage from areas flanking OA lesions compared to cartilage from macroscopically “normal” unaffected regions, while decreased in “late-stage” OA cartilage lesions. This increase in anabolic state was associated with a marked upregulation of XT-I expression and activity in cartilage “next to lesion” while a decrease in the “late-stage” OA cartilage. Importantly, XT-I inhibition by shRNA or forced-expression with a pCMV-XT-I construct correlated with the modulation of GAG anabolism in human cartilage explants. The observation that XT-I gene expression was down-regulated by IL-1β and up-regulated by TGF-β1 indicates that these cytokines may play a role in regulating GAG content in human OA. Noteworthy, expression of IL-1β receptor (IL-1R1) was down-regulated whereas that of TGF-β1 was up-regulated in early OA cartilage. Theses observations may account for upregulation of XT-I and sustained GAG synthesis prior to the development of cartilage lesions during the pathogenic process of OA

    A mutation which disrupts the hydrophobic core of the signal peptide of bilirubin UDP-glucuronosyltransferase, an endoplasmic reticulum membrane protein, causes Crigler-Najjar type II

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    Crigler-Najjar (CN) disease is caused by a deficiency of the hepatic enzyme, bilirubin UDP-glucuronosyltransferase (B-UGT). We have found two CN type II patients, who were homozygous for a leucine to arginine transition at position 15 of B-UGT1. This mutation is expected to disrupt the hydrophobic core of the signal peptide of B-UGT1. Wild type and mutant B-UGT cDNAs were transfected in COS cells. Mutant and wild type mRNA were formed in equal amounts. The mutant protein was expressed with 0.5% efficiency, as compared to wild type. Mutant and wild type mRNAs were translated in vitro. Wild type transferase is processed by microsomes, no processing of the mutant protein was observed

    One step hydrothermal synthesis of TiO2 with variable HCl concentration: Detailed characterization and photocatalytic activity in propene oxidation

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    TiO2 materials have been prepared by a novel one-step hydrothermal synthesis method at mild conditions (low temperature and time) using titanium tetraisopropoxide as precursor and HCl solutions of different concentration, ranging from 0.5 to 12 M. A detailed physico-chemical characterization has been done, putting especial attention to the quantification of crystallinity and surface OH content. All the obtained samples have high surface areas (100–135 m2/g), small anatase crystal size (8–11 nm) and high crystallinity (around 80%). The concentration of the HCl used in the synthesis has a significant effect on the two first mentioned parameters and on the proportion of crystalline phases (anatase-brookite-rutile) developed. There is a good correlation between the amount of hydroxyl surface groups and the specific surface area (SBET), but regarding surface density of OH groups there are, as well, some differences between samples (the samples with higher OH surface densities are those prepared with less concentrated HCl solutions). Most of the prepared photocatalysts are more active than commercial TiO2-P25 in the gas phase oxidation of propene at low concentration. The best photocatalytic performance is found for samples prepared with 0.5 and 0.8 M HCl, what can be explained by a suitable combination of properties: high surface area and developed porosity, high surface OH groups’ content and density and large proportion of anatase with small crystal size.The authors thank the Spanish Ministry of Economy and Competitiveness (MINECO) and FEDER, project of reference CTQ2015-66080-R, GV/FEDER (PROMETEOII/2014/010) and University of Alicante (VIGROB-136) for financial support

    TiO2-AC hybrid materials to produce H2 and biogas by photocatalytic decomposition of acetic acid

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    ComunicaciĂłn presentada en 13th European Congress on Catalysis, EuropaCat, Florence, Italy, 27 August-01 September 2017.The authors thank MINECO (CTQ2015-66080-R), Generalitat Valenciana/Feder (PROMETEOII/2014/010) and Universidad de Alicante (VIGROB-136) for financial support

    Síntesis hidrotermal de materiales híbridos TiO2-carbón para su aplicación en fotocatálisis

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    Comunicación presentada en la XIV Reunión del Grupo Español del Carbón, Málaga, 22-25 octubre 2017.Los autores agradecen la financiación económica a los proyectos CTQ2015-66080-R (MINECO/FEDER), PROMETEOII/2014/010 (GV/Feder) y VIGROB-136 (UA)
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