302 research outputs found

    Whiteboard Animations for Flipped Classrooms in a Common Core Science General Education Course

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    [EN] Whiteboard animation, an engaging tool for teaching and learning, consists of a series of hand-drawing illustrations with voice-over narration to explain complex and abstract ideas. Our team had produced four short whiteboard animations tailor-made for a common core science general education (GE) course. This study aims at evaluating the effectiveness of using these whiteboard animations for flipped classrooms in the common core science GE course. The pre-tutorial survey showed that students who watched the animations got significantly higher average marks in the quizzes at the beginning of the tutorials (p<0.001). The post-tutorial feedback survey indicated that the whiteboard animations attracted 67% of students to watch the animations. For students who watched the animations, over 86% of them reported that the animations raised their interest in the issues discussed in the tutorial classes, and learning materials in the form of whiteboard animation were more interesting than lecture videos; more than 90% of the students agreed the whiteboard animations were helpful in (i) understanding the assigned readings, (ii) clarifying the concepts of the discussed issues, and (iii) gaining the related knowledge before the tutorial. We concluded that whiteboard animation is an effective and engaging tool for flipped classrooms in the common core science GE course.We want to thank the Centre for eLearning and Innovation Technology of The Chinese University of Hong Kong for their support. This project was funded by the Micro-module Courseware Development Grant Scheme.Li, M.; Lai, CW.; Szeto, WM. (2019). Whiteboard Animations for Flipped Classrooms in a Common Core Science General Education Course. En HEAD'19. 5th International Conference on Higher Education Advances. Editorial Universitat Politècnica de València. 929-938. https://doi.org/10.4995/HEAD19.2019.9250OCS92993

    Optimization of processing parameters for the preparation of phytosterol microemulsions by the solvent displacement method

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    The purpose of this study was to optimize the parameters involved in the production of water-soluble phytosterol microemulsions for use in the food industry. In this study, response surface methodology (RSM) was employed to model and optimize four of the processing parameters, namely, the number of cycles of high-pressure homogenization (1−9 cycles), the pressure used for high-pressure homogenization (100−500 bar), the evaporation temperature (30−70 °C), and the concentration ratio of microemulsions (1−5). All responses—particle size (PS), polydispersity index (PDI), and percent ethanol residual (%ER)—were well fit by a reduced cubic model obtained by multiple regression after manual elimination. The coefficient of determination (R2) and absolute average deviation (AAD) value for PS, PDI, and %ER were 0.9628 and 0.5398%, 0.9953 and 0.7077%, and 0.9989 and 1.0457%, respectively. The optimized processing parameters were 4.88 (approximately 5) homogenization cycles, homogenization pressure of 400 bar, evaporation temperature of 44.5 °C, and concentration ratio of microemulsions of 2.34 cycles (approximately 2 cycles) of high-pressure homogenization. The corresponding responses for the optimized preparation condition were a minimal particle size of 328 nm, minimal polydispersity index of 0.159, and <0.1% of ethanol residual. The chi-square test verified the model, whereby the experimental values of PS, PDI, and %ER agreed with the predicted values at a 0.05 level of significance

    HIP-KNEE control for gait assistance with Powered Knee Orthosis

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    A Powered Knee Orthosis (PKO) was developed for the elderly and patients with disordered gait to regain normal walking. In order to enhance the PKO performance and reduce system complexity especially for people with muscle weakness in their knee joints, an algorithm named HIP-KNEE control is proposed. This algorithm is based on the analysis of kinematic gait model, and the desired knee joint angle (KNEE) is estimated from the measurements of hip joint angle (HIP). The relationship between HIP and KNEE is modeled as a polynomial, which can be easily implemented to an embedded controller for real-time control. This control method is suitable to subjects with good function in hip joint, and it can provide help in walking without special training. An Inertia Measurement Units (IMU) is used for obtaining HIP input, and integrated with a footswitch for checking the heel condition; the gait assistance performance can be further improved

    Response surface modeling of processing parameters for the preparation of phytosterol Nanodispersions using an emulsification-evaporation technique.

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    The purpose of this study was to optimize the production parameters for water-soluble phytosterol nanodispersions. Response surface methodology (RSM) was employed to model and optimize three of the processing parameters: mixing time (t) by conventional homogenizer (1–20 min), mixing speed (v) by conventional homogenizer (1,000–9,000 rpm) and homogenization pressure (P) by high-pressure homogenizer (0.1–80 MPa). All responses [i.e., mean particle size (PS), polydispersity index (PDI) and phytosterols concentration (Phyto, mg/l)] fitted well to a reduced quadratic model by multiple regressions after manual elimination. For PS, PDI and Phyto, the coefficients of determination (R 2) were 0.9902, 0.9065 and 0.8878, respectively. The optimized processing parameters were 15.25 min mixing time, 7,000 rpm mixing speed and homogenization pressure 42.4 MPa. In the produced nanodispersions, the corresponding responses for the optimized preparation conditions were a PS of 52 nm, PDI of 0.3390 and a Phyto of 336 mg/l

    Physico-chemical and quality characteristics of virgin coconut oil – a Malaysian survey

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    A total of 1 0 virgin coconut oil (VCO) samples from Malaysian market were collected and analysed for their physico-chemical and quality characteristics. Two of the samples were produced using MARDI’s technologies i.e. dry and wet processes. The remainders of the samples were produced either through natural fermentation or mechanical process. The analyses were divided based on physico-chemical characteristics and quality characteristics. As for the physico-chemical characteristic, eight types of analysis were performed i.e. relative density, refractive index, saponification value, iodine value, unsaponification matter, specific gravity, slip melting point and fatty acid composition. In addition, six types of analysis were carried out to determine the quality of the VCO. Physico-chemical characteristic analysis of all VCO samples fall within narrow ranges. However, for quality characteristics, some samples showed bad quality oil especially for the free fatty acid and peroxide value. The percentage of free fatty acid obtained from these samples were >0.5% and peroxide value >3 meq/kg. Total plate counts of most samples were zero. In terms of contaminants, copper, lead and arsenic were found to be below detectable levels except for iron. A few samples had high iron content (more than 5 mg/kg) which may enhance oxidative deterioration in the oil

    An Epstein-Barr virus–encoded microRNA targets PUMA to promote host cell survival

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    Epstein-Barr virus (EBV) is a herpesvirus associated with nasopharyngeal carcinoma (NPC), gastric carcinoma (GC), and other malignancies. EBV is the first human virus found to express microRNAs (miRNAs), the functions of which remain largely unknown. We report on the regulation of a cellular protein named p53 up-regulated modulator of apoptosis (PUMA) by an EBV miRNA known as miR-BART5, which is abundantly expressed in NPC and EBV-GC cells. Modulation of PUMA expression by miR-BART5 and anti–miR-BART5 oligonucleotide was demonstrated in EBV-positive cells. In addition, PUMA was found to be significantly underexpressed in ∼60% of human NPC tissues. Although expression of miR-BART5 rendered NPC and EBV-GC cells less sensitive to proapoptotic agents, apoptosis can be triggered by depleting miR-BART5 or inducing the expression of PUMA. Collectively, our findings suggest that EBV encodes an miRNA to facilitate the establishment of latent infection by promoting host cell survival

    Mindfulness-based cognitive therapy v. group psychoeducation for people with generalised anxiety disorder: randomised controlled trial

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    Background: Research suggests that an 8-week mindfulness-based cognitive therapy (MBCT) course may be effective for generalised anxiety disorder (GAD). Aims: To compare changes in anxiety levels among participants with GAD randomly assigned to MBCT, cognitive–behavioural therapy-based psychoeducation and usual care. Method: In total, 182 participants with GAD were recruited (trial registration number: CUHK_CCT00267) and assigned to the three groups and followed for 5 months after baseline assessment with the two intervention groups followed for an additional 6 months. Primary outcomes were anxiety and worry levels. Results: Linear mixed models demonstrated significant group × time interaction (F(4,148) = 5.10, P = 0.001) effects for decreased anxiety for both the intervention groups relative to usual care. Significant group × time interaction effects were observed for worry and depressive symptoms and mental health-related quality of life for the psychoeducation group only. Conclusions: These results suggest that both of the interventions appear to be superior to usual care for the reduction of anxiety symptoms

    Efeitos do tratamento com captopril e losartan em ratos Wistar e ratos espontaneamente hipertensos submetidos a hipertensão arterial pulmonar com monocrotalina

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    A hipertensão arterial pulmonar (HAP) é uma doença que se inicia com o aumento da resistência das arteríolas pulmonares. Após a sua instalação, sucedem-se várias alterações sobre os sistemas cardiovascular, respiratório e autonômico. Apesar dos trabalhos disponíveis na literatura, o desenvolvimento desta doença em modelos experimentais de hipertensão arterial sistêmica permanece ainda por ser estudado, bem como os efeitos terapêuticos de bloqueadores do sistema renina-angiotensina na reversão desta doença. Os objetivos deste estudo foram avaliar os efeitos cardiovasculares, autonômicos e respiratórios promovidos pela HAP induzida pela monocrotalina (MCT) em ratos Wistar e SHR e os efeitos terapêuticos do tratamento crônico com captopril e losartan na reversão da HAP. Para tanto, foram utilizados ratos Wistar (150-180g) e SHR (150-180g), divididos nos seguintes grupos: Wistar controle tratado com salina ou MCT (WIS-CON-SAL e WIS-CON-MCT, respectivamente), SHR controle tratado com salina ou MCT (SHR-CON-SAL e SHR-CON-MCT, respectivamente), Wistar tratados com Captopril + salina ou MCT (WIS-CPT-SAL e WIS-CPT-MCT, respectivamente), SHR tratados com Captopril + salina ou MCT (SHR-CPT-SAL e SHR-MCT-CPT, respectivamente), Wistar tratados com Losartan + salina ou MCT (WIS-LOS-SAL e WIS-LOS-MCT, respectivamente), SHR tratados com Losartan + salina ou MCT (SHR-LOS-SAL e SHR-LOS-MCT, respectivamente). Os animais tratados com MCT receberam uma única injeção subcutânea (60 mg/Kg SC) e os controles receberam o mesmo volume de salina (~0,8 mL). Ao término da 3ª senama, quando os animais MCTs controle apresentaram HAP, foi feito o tratamento com captopril (100 mg/Kg/mL) ou losartan (30 mg/Kg/mL) na água de beber por 2 semanas no volume diário de 30 mL. Após o tratamento com captopril ou losartan, foram realizados os registros cardiovasculares, respiratórios, gasométricos e a histologia pulmonar. Os resultados mostraram um significativo aumento do Índice Pulmonar nos animais controles tratados com MCT (Wistar e SHR) quando comparados com seus respectivos controles. As pressões ventriculares (PSmáx, PDI e PDF) também foram significativamente aumentadas nos grupos MCTs, bem como os valores de pressão arterial sistólica and diastólica, frequência cardíaca, pressão de pulso e labilidade da pressão arterial média. O tratamento com captopril normalizou todos os parâmetros estudados, no entanto, o losartan se mostrou ineficiente em normalizar os parâmetros hemodinâmicos. As análises morfométricas mostraram um espessamento da camada média dos dos ramos distais da artéria pulmonar e uma diminuição do lúmen nos grupos tratados com MCT. O tratamento com captopril e losartan normalizou estes parâmetros, embora o grupo tratado com losartan tenha sido menos eficaz que o captopril, pois os tratamentos mostraram diferenças significativas entre si. Quanto a avaliação autonômica, os animais MCT mostraram aumento do tônus simpático cardíaco e redução do tônus parassimpático cardíaco. Novamente, o tratamento com captopril normalizou estes parâmetros, enquanto que o losartan foi ineficaz em normalizá-los. Quanto aos parâmetros respiratórios, observamos aumentos no volume corrente, na frequência respiratória, na ventilação minuto e na ventilação alveolar dos animais controles tratados com MCT. Apenas o tratamento com captopril normalizou estes parâmetros. A avaliação gasométrica mostrou que os grupos controles tratados com MCT apresentaram redução da pressão parcial de O2 (hipóxia), aumento da pressão parcial de CO2 (hipercapnia), queda da porcentagem de saturação da hemoglobina (% Hb), aumento do bicarbonato (HCO3-) e acidose. O tratamento com captopril normalizou todos os parâmetros gasométricos, enquanto que o mesmo não foi observado com o losartan para os animais SHR submetidos a HAP. Nossos resultados mostraram que a MCT induziu ao quadro de HAP nos animais Wistar e SHR, bem como importantes alterações cardiovasculares, autonômicas, respiratórias, gasométricas e morfológicas pulmonares. Os tratamentos com captopril e losartan foram capazes de reverter a HAP em animais Wistar e SHR, porém, o captopril se mostrou mais eficiente em normalizar esses parâmetros quando comparados ao losartan. Estes resultados sugerem que o uso de bloqueadores do sistema renina angiotensina pode ser uma opção terapêutica para o tratamento da HAP. Palavras chave: hipertensão arterial pulmonar; monocrotalina; SHR; captopril; losartan
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