Axial Ligand Mutant: H229A

Many pathogenic bacteria use their iron acquisition mechanisms to live inside hosts. Streptococcus pyogenes is a pathogenic bacterium that uses streptococcal iron acquisition ABC transporter to obtain heme. SiaA (HtsA, spy1795), a lipoprotein located on the cell surface, serves as a heme binding protein. To understand the iron-uptake mechanism, histidine 229, one of the two proposed axial ligands in SiaA, was mutated to alanine. SiaA H229A was expressed in E. coli, lysed by French Press, and purified by fast protein liquid chromatography (FPLC). SDS-PAGE indicated that pure protein was isolated. Nickel affinity FPLC gave purer H229A when 0.5 M imidazole was added to the binding buffer. Overall, histidine 229 is likely to be an axial ligand in wild type SiaA, as shown by the fact the mutant readily lost heme as evidenced by UV-vis spectra

Online Learning Management in Covid-19 Pandemic: Case in Vietnam

The world is dealing with the COVID-19 epidemic, which has created enormous impacts on education, especially on learning management, requiring the adjustment and implementation of an online learning system effectively.The process of digital transformation has been promoted rapidly to adapt to new conditions in Education.Nowadays the online system has facilitated students of all levels to study at anytime and anywhere owing to the development of technologies.However, the existence and limits ofonline teaching and learning have been mentioned such as the complicated implementation or limited communication of active teaching methods compared to an actual classroom. Therefore, innovative teaching strategies and models are now required to be more diverse to encourage learners to focus on the lesson.In this study, we proposed an optimal paradigm of online learning management: the combination of several supported programs to effectivelymanage the teaching process. The approach has been appliedtothe Basic Informatics course for students majoring in Primary Education at the Thai Nguyen University of Education, Vietnam, and suggesteda flexible approach to stimulate learners' enthusiasm, express opinions, and actively participate in activities for enhancing their achievements. In addition, the investigation and discussion from lecturers and students about the digital transformation challenges in learning management also were presented and proposed the necessary information for the educational process

ONLINE LEARNING AND ITS POTENTIAL IN DEVELOPING EFL LEARNER AUTONOMY: ENGLISH-MAJORED STUDENTS' PERCEPTIONS

Learner autonomy is now regarded as a desirable goal in tertiary education as it is found to comply with learner-centered approaches and enable students to pursue life-long learning (Sinclair, 2000a; Ciekanski, 2007). In the time of COVID-19 pandemic, the essential to conduct in-depth investigations into leaner autotomy and online learning has become more urgent, especially in the context of a university in Vietnam. This quantitative research responded to such a pressing call by exploring two aspects: (1) the students’ perception of online learning, and (3) the potentiality of online learning for developing learner autonomy. Quantitative data were collected through questionnaires administered to 199 English-majored students in the context of a university in Mekong Delta. The results revealed that the students possessed positive perceptions toward online learning. Furthermore, the potentiality of online learning was explored including the ability of (1) planning learning experience, (2) evaluating learning performance, (3) determining learning goals, (4) self-controlling learning process, (5) taking responsibility for learning decision. Last but not least, this study expected that the proposed pedagogical implications will contribute to the innovation of promoting learner autonomy in online learning in the context of a university in the Mekong Delta of Vietnam.  Article visualizations

Assessment of earthquake-induced ground liquefaction susceptibility for Hanoi city using geological and geomorphologic characteristics

In this paper, the earthquake-induced liquefaction susceptibility of Hanoi city is assessed using the recent published geological and geomorphologic data. A combination of classification methods based on the distribution of sedimentary deposits proposed by Youd and Perkins (1978) and geomorphologic units proposed by Iwasaki (1982) was applied. The subsurface lithology and geomorphologic maps were combined in a GIS platform for assessing the liquefaction susceptibility of Hanoi city.The resulting map shows that the liquefaction hazard of Hanoi city classified into four categories: high, moderate, low liquefaction potential and not likely areas. In the most of Hanoi area, the ground liquefaction potentials are moderate. The high liquefaction likely areas spread along the river beds and around the lake areas. The not likely and low liquefaction potential areas are observed mainly in the northwest and northeast of the study region such as Chanchim, Soc Son, and Bavi mountains. The present map can help the scientists, engineers, and planners to have the general information on regional liquefaction potential of the Hanoi city. ReferencesBird JF, Bommer JJ, 2004b. Earthquake Losses due to Ground Failure. Submitted to Engineering Geology, 75(2), 147-179.Bird Juliet F, Bommer Julian J., 2004a. Evaluating earthquake losses due to ground failure and identifying their relative contribution (Paper no. 3156). In Proceedings of the 13th world conference on earthquake engineering, Vancouver, B.C., Canada, august 1-6.Bui Van Duan, Nguyen Cong Thang, Nguyen Van Vuong, Pham Dinh Nguyen, 2013. The magnitude of the largest possible earthquake in the Muong La-Bac Yen fault zone. J. Sci. of the Earth, 35(1), 53-59.Dao Dinh Bac, Dang Van Bao, 2010. Geomorphologic characteristics, the ancient river beds system of the capital city and their values to the development of the Thang Long - Hanoi. International Workshop commemorating the 1000 years of Thang Long, Hanoi. Vietnam national University, Hanoi.Ganapathy, G. P., Rajawat, A. S., 2012. Evaluation of liquefaction potential hazard of Chennai city, India: using geological and geomorphological characteristics. Natural hazards, 64(2), 1717-1729.Goyal, A., Sinha, R., Chaudhari, M. and Jaiswal, K., 2001. Performance of Reinforced Concrete Buildings in Ahmedabad during Bhuj Earthquake January 26, 2001. Workshop on Recent Earthquakes of Chamoli and Bhuj: Volume I, Roorkee, India, May 24-26.Iwasaki, T., Tokida, K., Tatsuoka, F., Watanabe, S., Yasuda, S., Sato, H., 1982. Microzonation for soil liquefaction potential using simplified methods. In Proceedings of the 3rd international conference on microzonation, Seattle, 3, 1310-1330.Kuribayashi E., Tatsuoka, F., 1975. Brief review of liquefaction during earthquake in Japan,” Soils and Foundations, 15(4), 81-92.Lew M, Naeim F, Huang SC, Lam HK, Carpenter LD, 2000. Geotechnical and geological effects of the 21 September 1999 Chi-Chi earthquake, Taiwan. Structural Design of Tall Buildings, 9, 89-106.National Research Council, 1985. Ishihara 1985. Liquefaction of Soils During Earthquake, National Academy press, 240, p.34. Nguyen Hong Phuong (Project Manager), 2002. Study of seismic risk of Hanoi city. Project code 01C-04/09-2001-2. Institute for Marine Geology and Geophysics, VAST.Nguyen Hong Phuong (Project Manager), 2007. Application of GIS technology to Development of a model for seismic risk analysis for Hanoi city. Institute for Marine Geology and Geophysics, VAST.Nguyen Hong Phuong (Project Manager), 2014.  Estimation of Site Effects and Assessment of Urban Seismic Risk for Hanoi city. National Scientific Research Project Final report, Institute of Geophysics, VAST.Nguyen Hong Phuong and Pham The Truyen, 2014. Probabilistic seismic hazard assessment for South Central Vietnam. J. Sci. of the Earth, 36(4), 451-461.Phan Trong Trinh, Hoang Quang Vinh, Nguyen Van Huong, Ngo Van Liem, 2013. Active fault segmentation and seismic hazard in Hoa Binh reservoir, Vietnam. Cent. Eur. J. Geosci, 5(2), 223-235.Phan Trong Trinh, Ngo Van Liem, Nguyen Van Huong, Hoang Quang Vinh, Bui Van Thom, Bui Thi Thao, Mai Thanh Tan, Nguyen Hoang, 2012. Late Quaternary tectonics and seismotectonics along the Red River fault zone, North Vietnam. Earth-Science Reviews 114, 224-235.Susumu Yasuda, Nozomu Yoshida, Hiroyoshi Kiku, Hidenori Abo, and Masato Uda, 2001. Analyses of Liquefaction-Induced Deformation of Grounds and Structures by a Simple Method (March 26). International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics, p.27. http://scholarsmine.mst.edu/icrageesd/04icrageesd/session04/27.Updike, R. G., Egan, J. A., Moriwaki, Y., Idriss, I. M., Moses, T. L., 1988. A model for earthquake-induced translatory landslides in Quaternary sediments. Geological Society of America Bulletin, 100(5), 783-792.Vu Thanh Tam (Project Manager), 2014. Study and propose a reasonable threshold for preventing the subsidence caused by ground water exploitation, pilot application for downtown area of the Hanoi city. Final report of the Scientific research and technology development Project, National Center for water resource planning and investigation. Ministry of Natural Resources and Environment.Youd T. L., 1993. Liquefaction, ground failure and consequent damage during the 22 April 1991 Costa Rica earthquake. Abridged from EERI Proceedings: U.S. Costa Rica Workshop, http://nisee.berkeley.edu/costarica/Youd T. L., and Hoose S.N., 1977.  Liquefaction Susceptibility and Geologic Setting, Proceedings, 6th World Conference on Earthquake Engineering, New Delhi, India, 6, 37-42.Youd T. L., and Perkins D. M., 1978. Mapping liquefaction-induced ground failure potential. Journal of the Geotechnical Engineering Division, ASCE, 104, GT4, 433-446

Analyze the Determinants of Capital Structure for Vietnamese Real Estate Listed Companies

This study adopts a two - step system general method of moments (GMM) approach towards investigating the determinants of capital structure for the listed real estate firms on Ho Chi Minh stock exchange (HSX) in Viet Nam from 2010 to 2015. The determinants of capital structure are mixed and different for short-term and long-term indicators. The real estate firms tend to use more debts to finance their investment. Vietnamese real estate firms should focus on balance structure debt due to complicated impacts of the determinants to their capital structure. There are some implications for the real estate companies and policy of the Government that are based on the empirical results. Keywords: determinants of capital structure, real estate company, general method of moments. JEL Classifications: G32, R

Insights into Human-Induced Pluripotent Stem Cell-Derived Astrocytes in Neurodegenerative Disorders

Most neurodegenerative disorders have complex and still unresolved pathology characterized by progressive neuronal damage and death. Astrocytes, the most-abundant non-neuronal cell population in the central nervous system, play a vital role in these processes. They are involved in various functions in the brain, such as the regulation of synapse formation, neuroinflammation, and lactate and glutamate levels. The development of human-induced pluripotent stem cells (iPSCs) reformed the research in neurodegenerative disorders allowing for the generation of disease-relevant neuronal and non-neuronal cell types that can help in disease modeling, drug screening, and, possibly, cell transplantation strategies. In the last 14 years, the differentiation of human iPSCs into astrocytes allowed for the opportunity to explore the contribution of astrocytes to neurodegenerative diseases. This review discusses the development protocols and applications of human iPSC-derived astrocytes in the most common neurodegenerative conditions

Impact of Foreign Direct Investment on Economic Restructuring in Bac Ninh

In recent years, foreign direct investment (FDI) has played an important role in Bac Ninh’s economic restructuring. Of all provinces, Bac Ninh has always been leading the way for attracting foreign investment in Vietnam. The goal of this article is to study the relationship between FDI and the structure of economy of Bac Ninh. We use Ordinary Least Squares regression (OLS) to analyze the influence of the province’s FDI on its economic restructuring over the period from 2009 to 2019. The result partly shows that the FDI has had a strong impact on Bac Ninh’s economic restructuring in both speed and quality. Through these findings, we propose several recommendations for the local authorities to continue to attract the FDI and reinforce the positive impacts of the FDI on the province’s economic restructuring in the future. Keywords: Bac Ninh, foreign direct investment (FDI), economic restructuring, OLS DOI: 10.7176/EJBM/12-15-03 Publication date:May 31st 202

Study of CYP3A5 genetic polymorphism in Vietnamese Kinh ethnic group

Cytochrome P450 3A5 (CYP) belongs to the CYP3A cluster, which encode for several enzymes involved in metabolism of various drugs, endogenous substrates as well as exogenous compounds. Among the four genes of CY3A cluster, CYP3A5 plays an important role in pharmacogenetics since this enzyme metabolizes over 30% of the clinically prescribed drugs. The inter-individual variability in clearance of CYP3A substrates mainly depends on the genetic factors. In the present study, after collecting peripheral bloods samples from 100 unrelated healthy Kinh ethnic group in Vietnam, Sanger sequencing was used in order to determine the CYP3A5 variants responsible for enzyme activity alteration (*3, *6, *8 and *9). It was shown that CYP3A5*3 is the most prevalent variant with 67.5%, in which a haft of individuals carrying *3 were homozygous for this allele. In contrast, the variants *6, *8 and *9 were not found the study subjects. The data observed in current study would support dosing of drugs that metabolized by CYP3A5 and thereby increase treatment outcome.