Characterization of Structural Transition and Heterogeneity under Compression for Liquid Al2O3 Using Molecular Dynamics Simulation

We have performed a simulation of the structural transition and Structural Heterogeneity (SH) in liquid Al2O3 at 3500 K, in the range of 0–100 GPa. The results confirmed that the network structure of liquid alumina is built mainly from AlOx (x = 3, 4, 5, 6, 7) units, which are related to each other through the common oxygen atoms. The existence of separate AlO3-, AlO4-, AlO5-, AlO6- and AlO7- phases, where SH of the network structure can be sufficiently determined, besides, the existence of separate phases is clarified for SH in the liquid of Al2O3. In particular, at a pressure below 10 and beyond 20 GPa, AlOx units are uniformly distributed in the space and non-uniformly distributed in the range 10-20 GPa. Our study is expected to contribute to a simple way to determine the structural heterogeneity and diffusion coefficients of oxide systems. Doi: 10.28991/HIJ-2022-03-02-08 Full Text: PD

Impairment of Assets Under Perspectives of International and Vietnamese Accounting

This study investigates the impairment of assets on financial reportings of three separate entities - Vietnam Prosperity Joint-Stock Commercial Bank (VPBank), The Bank of East Asia (BEA) and The Nestlé Group - in the financial year of 2017. By bringing out the differences between international accounting system of asset impairment (IAS 36) and Vietnamese accounting system (VAS), this research has determined the gap between two sets of financial statements under IFRS and VAS in conveying the business performance and financial position. The empirical results show Vietnam’s necessary for a convergence in asset impairment with international accounting system. Therefore, we provide some recommendations for Vietnam in applying asset impairment regarding to IAS 36 partly or completely. Keywords: Asset impairment, International accounting, Vietnamese accounting. DOI: 10.7176/RJFA/10-12-07 Publication date:June 30th 2019

AN INVESTIGATION INTO QUANG TRI PRIMARY SCHOOL ENGLISH LANGUAGE TEACHER’S PERSPECTIVE OF ICT INTEGRATION DURING THE COVID-19 PANDEMIC

With the transition from face-to-face classes to online classes during Covid-19 epidemic, teachers in Quang Tri have no choice but to integrate ICT into their teaching. At this time ICT has become the most essential tool in educational settings and the subject of many researchers. This study aims to investigate how English teachers perceived ICT integration in terms of the benefits, difficulties as well as challenges of incorporating ICT. The study adopted both quantitative and qualitative methods of data collection, i.e., questionnaires and interviews. The findings revealed that the majority of English teachers had a positive perception of integrating ICT due to its effectiveness. However, it was also reported that lack of technical support from schools, and limited knowledge and training in ICT discouraged teachers from using ICT. The study offers useful implications for teachers to integrate ICT in teaching English during the pandemic time.  Article visualizations

STUDENTS’ PERCEPTIONS OF ACTIVE LEARNING IN INTRODUCTION TO LITERATURE

There is a growing interest in active learning as a shift from traditional lecturing to improving student-centred learning in English. However, in the Vietnamese context of teaching and learning at tertiary levels, little research has examined students’ perceptions of active learning in approaching Introduction to Literature. This study is therefore aimed to look into this area of interest. Participants in this study were 94 students from junior and seniors majoring in high-quality programs at a university in the Mekong Delta. Data were collected from questionnaires. The findings show that students had positive perceptions of active learning in studying this course. Implications for teaching and learning this course are made.  Article visualizations

EFFECTS OF SALT STRESS ON PLANT GROWTH AND BIOMASS ALLOCATION IN SOME WETLAND GRASS SPECIES IN THE MEKONG DELTA

Salt stress causes serious damage to many cellular and physiological processes that leads to yield reduction. The study induced salt stress using Hoagland solution added NaCl to evaluate its effects on plant growth and biomass allocation of some wetland grass species in order to identify salt-tolerant species for replacing and/or supplementing rice/grass in rice-shrimp model and salt-affected area in the Mekong Delta. The study also seeks to evaluate the response of leaf chlorophyll (SPAD unit) and proline content in salt-treated plants to varying application of salinity. Typha orientalis, Lepironia articulata, Eleocharis dulcis and Scirpus littoralis were studied in hydroponics condition with four levels of NaCl of 5, 10, 15, 20‰ and the control treatment (without adding NaCl). The experiment was arranged in a completely randomized design with 3 replications. The salt-treated plants showed visually clear responses of inhibited growth under salt stress condition compared to the control plants. Among the four studied species, T. orientalis produced the highest dry shoot biomass (15.5 g DW/plant), while E. dulcis had the lowest value (2.8 g DW/plant). However, only T. orientalis showed significantly decreased in biomass as salinity increased with 9.3 and 4.6 times lower of fresh and dry biomass in plants grown at the salinity level of 20‰ compared to those grown in the control treatment. The other three plant species did not affect by salinity levels. The results indicated that S. littoralis, L. articulata and E. dulcis could tolerate at high salinity of 20‰ (eq. to the EC value in the nutrient solution of 38.0 dS/m) and could be potential candidate to grow in the rice-shrimp model or in the salt-affected soils. 

Gender income gap in Vietnam in the 2000s : evidence from household surveys

This paper investigates the determinants and characteristics of changes in the gender wage gap between 2004 and 2010 in Vietnam. Labour force structure, employment by gender, education, and skill level, labour force participation, types of enterprises, geographical area, and wage structure are key determinants analyzed in this study. Results reaffirm that traditional concepts and social bias towards women prevent their access to education and training, selection of occupations, and opportunities to improve professional and technical qualifications. Policy implications are reviewed

Effect of Polypyrrole on the Electrical, Dielectric and Mechanical Properties of Waterborne Epoxy Coatings

In this context, conducting composite based on waterborne epoxy system and polypyrrole (PPy) was investigated. The polypyrrole was synthesized by chemical oxidation polymerization. Its morphology and chemical structure were confirmed by using field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). Then, PPy was well-dispersed in the epoxy coating and had a good compatibility with the matrix. The effects of PPy on dielectric, electrical and mechanical properties of epoxy/PPy composites was examined. The dielectric constant and electrical conductivity of the coatings increased with addition of PPy fillers. Over to 15 wt. % of PPy loading, the volume resistivity of samples slightly decreased from 6.7 × 1010 to 1.5 × 1010 Ω cm. In contrast, the presence of PPy diminished both impact and abrasion resistance of the epoxy/PPy composites, down to 160 kg cm and 10.2 L/mil, respectively, but they stayed acceptable for the coatings. The results reveal that the epoxy containing polypyrrole is suitable for various electrical and dielectric applications

Distal radius fracture malunion: Importance of managing injuries of the distal radio-ulnar joint.

Background: Distal radius malunion is a major complication of distal radius fractures, reported in 0 to 33% of cases. Corrective osteotomy to restore normal anatomy usually provides improved function and significant pain relief. We report the outcomes in a case-series with special attention to the potential influence of the initial management. Material and methods: This single-centre retrospective study included 12 patients with a mean age of 35 years (range, 14–60 years) who were managed by different surgeons. There were 8 extra-articular fractures, including 3 with volar angulation, 2 anterior marginal fractures, and 2 intra-articular T-shaped fractures; the dominant side was involved in 7/12 patients. Initial fracture management was with an anterior plate in 2 patients, Kapandji intra-focal pinning in 5 patients, plate and pin fixation in 2 patients, and non-operative reduction in 3 patients. The malunion was anterior in 10 patients, including 2 with intra-articular malunion, and posterior in 2 patients. Corrective osteotomy of the radius was performed in all 12 patients between 2005 and 2012. In 11/12 patients, mean time from fracture to osteotomy was 168 days (range, 45–180 days). The defect was filled using an iliac bone graft in 7 patients and a bone substitute in 4 patients. No procedures on the distal radio-ulnar joint were performed. Results: All 12 patients were evaluated 24 months after the corrective osteotomy. They showed gains in ranges not only of flexion/extension, but also of pronation/supination. All patients reported improved wrist function. The flexion/extension arc increased by 40◦ (+21◦ of flexion and +19◦ of extension) and the pronation/supination arc by 46◦ (+13◦ of pronation and +15◦ of supination). Mean visual analogue scale score for pain was 1.7 (range, 0–3). Complications recorded within 2 years after corrective osteotomy were complex regional pain syndrome type I (n = 1), radio-carpal osteoarthritis (n = 3), and restricted supination due to incongruity of the distal radio-ulnar joint surfaces (n = 3). This last abnormality should therefore receive careful attention during the management of distal radius malunion. Discussion: In our case-series study, 3 (25%) patients required revision surgery for persistent loss of supination. The main error in these patients was failure to perform a complementary procedure on the distal radio-ulnar joint despite postoperative joint incongruity. This finding and data from a literature review warrant a high level of awareness that distal radio-ulnar joint congruity governs the outcome of corrective osteotomy for distal radius malunion

Oviposition of Aedes aegypti and Aedes albopictus on Ovitraps in Dry and Rainy Seasons in Southern Vietnam

Ovitraps were set inside and outside of 15 households in December 2012 (dry season) and August 2013 (rainy season) in 2 communes (An Thanh and Phu Hoa) of Binh Duong Province in southern Vietnam. Eggs laid in the ovitraps were collected after 4 days, dried, and soaked in water. Hatched larvae were transferred to cups and reared to adulthood to identify the species. The rate of positive ovitraps did not differ between December and August for Aedes aegypti, but it was lower in December for Ae. albopictus. The number of eggs laid per ovitrap by Ae. aegypti did not differ between December and August, while that for Ae. albopictus decreased significantly in December in both communes. Moreover, Ae. albopictus laid eggs in ovitraps placed outside the households. Therefore, it is necessary for future studies to investigate whether the major source containers for oviposition had dried in the dry season or Ae. albopictus entered diapause, leading to these observations

Depression, anxiety and stress among healthcare workers in the context of the COVID-19 pandemic: a cross-sectional study in a tertiary hospital in Northern Vietnam

IntroductionThe outbreak of coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) had significant effects on the mental well-being in general, particularly for healthcare professionals. This study examined the prevalence of depression, anxiety, and stress, and identified the associated risk factors amongst healthcare workers during the COVID-19 outbreak in a tertiary hospital located in Vietnam.MethodsWe conducted a cross-sectional study at a tertiary-level hospital, where the Depression Anxiety and Stress Scale 21 (DASS-21) web-based questionnaire was employed. We analyzed the determinant factors by employing multivariate logistic models.ResultsThe prevalence of depression, anxiety, and stress symptoms were 19.2%, 24.7%, and 13.9%, respectively. Factors such as engaging in shift work during the pandemic, taking care of patients with COVID-19, and staff’s health status were associated with mental health issues among health professionals. In addition, having alternate rest periods was likely to reduce the risk of stress.ConclusionThe prevalence of mental health problems in healthcare workers during the COVID-19 pandemic was relatively high. Having resting periods could potentially mitigate the development of stress among health professionals. Our findings could be taken into account for improving mental health of the health professional population