Replacing Face-To-Face Classes by Synchronous Online Technologies: The HOU Experience

AbstractSince 2009, HOU has been providing live virtual classes for various distance learningprograms.This paper will provide an opportunity to look at the issues involved in the use of thesemultimedia-enabled delivery approaches, the technology behind them, the logistics involved,and to provide an HOU perspective of the experiences encountered.The goal of research was to provide a systematic methods to implement the highlyinteractive live session. The additional goals was to design the portable hardware and easy touse software toolset as well as easy to follow guidelines on how to propel the lectures fromthe conventional dull chalk and talk and to minimise the number of staff required to give thelectures.Through a combination of surveys and feedback from lecturers and students, we are ableto better understand the obstacles and to continuously improve on the effectiveness of theseinteractive delivery approaches

Construction, verification of a software for the 2D dam-break flow and some its applications

In this paper the numerical method for the shallow water equations is studied. The paper consists of 3 sections. In the section 1 the theoretical basis and software IMECI-L2DBREAK for simulation of the 2D dam-break or dyke-break flows is outlined. In the section 2 some results in verification of the IMECH_2DBREAK by the test cases proposed in the big European Hydraulics Laboratories are shown. In the last section some applications of IMECH_2DBREAK for the inundation problem in the Red river delta in the Northern of Vietnam are presented

Differentiation Effect of Two Alkaloid Fractions from Vietnamese Lycopodiaceae on Mouse Neural Stem Cells

Various Lycopodium alkaloids have been studied for their various biological activities including anti-inflammatory, antioxidant, immunomodulatory, and neuroprotective activities. Moreover, these alkaloid compounds have high potential in the treatment of neuron degenerative disease. This study has been carried out to test the effect of Huperzia serrata (Thunb.) Trevis, and Lycopodium clavatum L alkaloid fractions on the mouse neural stem cells (NSCs). Firstly, the alkaloid fractions were used to verify its toxicity on NSCs. The multiple concentrations of alkaloid fractions from H. serrata (0.044; 0.088; 0.175; 0.35; 0.7; 1.4 mg/ml) and L. clavatum (0.031; 0.063; 0.125; 0.25; 0.50; 1.0; 2.0 mg/ml) have been used for the treatment of NSCs at period of 48h incubation. Results of the study suggested that the IC50 value of H. serrata and L. clavatum was 0.56 mg/ml and 0.50 mg/ml, respectively. Then, the NSCs were differentiated in the presence of 5 and 10 µg/ml of alkaloid fraction from H. serrata; 0.625 and 1.25 µg/ml of alkaloid fraction from L. clavatum for 6 days. Here, we observed the primary NSCs treated with alkaloid fraction extract from H. serrata showed the increased gene expression level of early neuron TUBB3 and neuron-specific cytoskeleton MAP2. On the other hand, the L. clavatum alkaloid fraction increased the expression of neural stem cell marker genes (Nestin and PAX6) and decreased neuron marker genes. In conclusion, these results established that alkaloid fraction from H. serrata promoted differentiation of the mouse NSCs to neuron cells, and L. clavatum extract had a capacity for stemness maintenance

TECHNICAL ASSESSMENT OF GAMMA-AMINO BUTYRIC ACID (GABA) PRODUCTION FROM RICE BRAN

This research focused on technical assessment of GABA production from rice bran through fermentation by Lactobacillus brevis. Influence of operating pressure on separation of GABA by nanofiltration membrane was investigated and 4 bar was suitable for the nanofiltration process. The purification of GABA by nanofiltration with constant feed volume was carried out and purity of GABA reached 4.8 folds, compared to feed, at 5 volumes of added water. At 40 of concentration factor in concentration of GABA solution by nanofiltration with full recycle of retentate, content of GABA reached 49.8 g/L. The production of GABA from defatted rice bran at pilot scale was carried out at 1,000 L/batch (equal to 200 kg of rice bran) of fermentation. Estimation of mass balance showed that, with 200 kg of defatted rice bran, 7.0 kg of GABA powder was obtained. Results indicated that, it is potential to produce GABA from rice bran through the fermentation by Lactobacillus brevis

Developing a zebrafish-based pipeline to investigate the biological properties of medicinal plant extracts from Northern Vietnam

peer reviewe

Discovering Novel Bioactivities of Controversial Food Additives by Means of Simple Zebrafish Embryotoxicity (ZET) Assays

peer reviewedThe rising concerns about controversial food additives’ potential hazardous properties require extensive yet animal-minimized testing strategies. Zebrafish embryos are the ideal in vivo model representing both human and environmental health. In this study, we exposed zebrafish embryos to eight controversial food additives. Our results indicate that Sodium Benzoate is a Cat.3 aquatic toxicant, while Quinoline Yellow is a strong teratogen. At high concentrations, non-toxic chemicals induced similar phenotypes, suggesting the impact of ionic strength and the applicability of the darkened yolk phenotype as an indicator of nephrotoxicity. Three food additives showed unpredicted bioactivities on the zebrafish embryos: Brilliant Blue could weaken the embryonic yolk, Quinoline Yellow may interfere with nutrient metabolism, and Azorubine induced precocious zebrafish hatching. In conclusion, the zebrafish embryo is ideal for high throughput chemical safety and toxicity screening, allowing systematic detection of biological effects—especially those unexpected by targeted in vitro and in silico models. Additionally, our data suggest the need to reconsider the safety status of food additives Quinoline Yellow, Brilliant Blue, Sodium Benzoate, and other controversial food additives in further studies, as well as pave the way to further applications based on the newly found properties of Brilliant Blue and Azorubine.Test d'additifs alimentaires et de leurs propriétés biologiques sur cellules et sur les poissons zèbres3. Good health and well-bein

Belgium

peer reviewedPurpose: Traditional medicines have been used in Vietnam for thousands of years, and still play an essential role in healthcare. However, so far, there is no clear definition of circumstances in which plants can be collected, conserved, and extracted; viable models for a productive and sustainable exploitation of natural extracts are missing, sometimes leading to severe and unfavorable consequences on health. In this study, we aim to develop a cost-effective pipeline to assess the pharmaco-/toxicological properties of these medicinal materials using the zebrafish embryo as an in vivo model. Methods: Medicinal plants extracts were prepared by incorporating in the design more standardized methods as the traditional ones, using increasing polarity solvents. After that, the zebrafish has been chosen as a whole animal model to determine the core of the biological properties of a specific extract. Embryotoxicity was analyzed by exposing extracts to zebrafish embryos, which were monitored at specific times during 4 days for survival and the presence of developmental malformations. In addition, the zebrafish transgenic line Tg(fli1:EGFP) displaying fluorescent endothelial cells was used to visualize blood vessels and detect effects on angiogenesis. Proof-of-concept experiments were done by passing samples from two plants: Caesalpinia sappan L. and Glochidion eriocarpum to evaluate its efficiency. Results: Effects of C. sappan L. extract on zebrafish embryonic morphology and lethality were determined in the corresponding concentration-response curves (LC50=500 mg/L and EC50=40 mg/L). Analysis of transgenic zebrafish showed the anti-angiogenic properties in a dose dependent manner. In addition, the interaction between this plant extract and the embryo chorion was explored. On the other hand, G. eriocarpum extract exposure led to a biphasic response from the zebrafish embryos, suggesting a protective role of the embryonic chorion. Our results may contribute to the design of a rational high throughput pharmacological screening approach using the zebrafish model

Electronic noses based on metal oxide nanowires: a review

Metal oxides are ideal for the fabrication of gas sensors: they are sensitive to many gases while allowing the device to be simple, tiny, and inexpensive. Nonetheless, their lack of selectivity remains a limitation. In order to achieve good selectivity in applications with many possible interfering gases, the sensors are inserted into an electronic nose that combines the signals from nonselective sensors and analyzes them with multivariate statistical algorithms in order to obtain selectivity. This review analyzes the scientific articles published in the last decade regarding electronic noses based on metal oxide nanowires. After a general introduction, Section 2 discusses the issues related to poor intrinsic selectivity. Section 3 briefly reviews the main algorithms that have hitherto been used and the results they can provide. Section 4 classifies the recent literature into fundamental research, agrifood, health, security. In Section 5, the literature is analyzed regarding the metal oxides, the surface decoration nanoparticles, the features that differentiate the sensors in a given array, the application for which the device was developed, the algorithm used, and the type of information obtained. Section 6 concludes by discussing the present state and points out the requirements for their use in real-world applications

Global Emissions: A New Contribution from the Shadow Economy

Based on the STIRPAT model and the EKC hypothesis, this study provides new evidences on the economic determinants of global emissions. The system-GMM estimations are used for the sample of 106 economies in the period of 1995-2012 to investigate the influences of income level, urbanization, industrialization, energy intensity, public expenditure, trade openness, FDI inflow, and especially shadow economy on total greenhouse emissions, CO2 emissions, CH4 emissions, and N2O emissions, respectively. This study contributes to the literature in three folds. First, the industrialization energy intensity are the main drivers for all emissions (excluding N2O). While, urbanization has positive effects on emissions excluding the case of CH4. Other drivers including public spending and economic integration (proxied by trade openness and FDI inflow) are also tested with interesting findings. Second, a higher level of shadow economy increases all emissions excluding CO2. Third, the determinants of emissions vary depending on the countries' income level. The study is supported by a battery of robustness checks and by various estimations in the short and long-run to identify the importance of emissions' drivers. Keywords: Emissions; CO2, CH4, N2O, Public expenditures, Economic integration, Shadow economy. JEL Classifications: F18, F64, O44, Q56, R11, O17 DOI: https://doi.org/10.32479/ijeep.724