Survey on Vietnamese teachers’ perspectives and perceived support during COVID-19

The COVID-19 pandemic has caused unprecedented damage to the educational system worldwide. Besides the measurable economic impacts in the short-term and long-term, there is intangible destruction within educational institutions. In particular, teachers – the most critical intellectual resources of any schools – have to face various types of financial, physical, and mental struggles due to COVID-19. To capture the current context of more than one million Vietnamese teachers during COVID-19, we distributed an e- survey to more than 2,500 randomly selected teachers from two major teacher communities on Facebook from 6th to 11th April 2020. From over 373 responses, we excluded the observations which violated our cross-check questions and retained 294 observations for further analysis. This dataset includes: (i) Demographics of participants; (ii) Teachers' perspectives regarding the operation of teaching activities during the pandemic; (iii) Teachers' received support from their schools, government bodies, other stakeholders such as teacher unions, and parents' associations; and (iv) teachers' evaluation of school readiness toward digital transformation. Further, the dataset was supplemented with an additional question on the teachers' primary source of professional development activities during the pandemic

Penetrating Keratoplasty for Keratoconus in Vietnamese Patients

BACKGROUND: Keratoconus is an ectatic corneal disorder that can impair the visual acuity. Up to now, penetrating keratoplasty (PK) remains the most common surgical procedure to treat severe keratoconus. In Vietnam, most keratoconus patients come to visit doctor at severe stage and were treated by PK, so we conduct this study. AIM: To evaluate the results of PK for keratoconus in Vietnamese patients. METHODS: This was a retrospective study of 31 eyes with keratoconus who underwent PK in VNIO from January 2005 to December 2014. RESULTS: The average visual acuity was 0.86 ± 0.37 logMAR (20/145). In the group of patients without amblyopia, best spectacle-corrected visual acuity of 20/60 or better was recorded in 75.9% of eyes and 93.1% of eyes achieved a best corrected visual acuity with hard contact lenses of 20/40 or better. Mean postoperative corneal power was 43.8 ± 4.5D. Mean corneal astigmatism was 5.9 ± 2.7D. 94.6% of grafts remained clear. Posterior subcapsular cataract developed in 22.6% of eyes. Graft rejection was recognized in 12.9% of eyes. CONCLUSION: PK is an effective procedure with high rate of graft survival for keratoconus patients. However, patients should be aware of the necessary of optical correction to gain the best VA after surgery

Evaluation of Phacoemulsification Cataract Surgery Outcomes After Penetrating Keratoplasty

BACKGROUND: Cataract is one of the reasons which causes impaired visual acuity (VA) of the eyes after penetrating keratoplasy (PK), which can be treated by cataract surgery after PK or triple procedure. Cataract surgery after PK has advantages that parameters of the eyes such as axial length, anterior chamber depth (ACD) as well as corneal curvature are stabilized after removing all sutures postoperatively, and intraocular lens (IOL) power can be calculated correctly. Therefore, postoperative VA will be improved significantly. In Vietnam, there have not been any study about cataract surgery after PK, therefore we conduct this research. AIM: To evaluate the outcomes of phacoemulsification cataract surgery following primary PK. METHODS: Non-randomized controlled intervention study. Ninteen eyes (19 patients) that underwent phacoemulsification plus IOL insertion after initial PK in Cornea department, Vietnam National Institute of Ophthalmology, from December 2013 to September 2014. RESULTS: All patients presented with reduced VA, including 17 eyes (89.9%) with VA ≤ 20/200, mean astigmatism was 7.9 ± 1.0 D. Clear corneal grafts in 16 eyes while corneal opacity was seen in 3 eyes. All eyes with cataract were diagnosed from grade 2. After cataract surgery, improved VA > 20/200 was achieved in 72.22% of cases. There was a markable reduce of postoperative astigmatism with 1,8 ± 0.8 D (p < 0.05). However, the immunologic graft reaction was presented in one eye, and two edematous corneas also reported after cataract surgery. After treatment, there was one cornea achieved its clarity. CONCLUSION: Phacoemulsification cataract surgery following initial PK showed good outcomes with improved postoperative VA, reduced astigmatism, and the ultimate graft survival rate was high

Did COVID-19 challenge the volatility of the sustainable stock market? An examination of Asian market

The coronavirus outbreak at the end of 2019 hit many aspects of the financial sector, especially the stock market. This research examines the impacts of the COVID-19 pandemic, exchange rates, gold price, and the Brent oil price on the volatility of the Sustainable Stock Market in Asia. A quantitative research method is applied using average monthly panel data from March 2020 to April 2022, covering the COVID-19 pandemic period. We employed panel regressions and applied Feasible Generalized Least Square (FGLS) in the analysis, which also serves as a robustness check. This study contributes to the literature by examining the variables significantly impacting sustainable investing, particularly in the sustainable stock market. Empirical results find that COVID-19, gold price and the exchange rate have negatively affected sustainable stock market volatility, while the Brent oil price has a positive impact on the volatility of the sustainable stock market. This study's recommendations infer that both investors and managers should consider the increase of COVID-19 cases and frequency-varying exchange rates to the USD on the Asian sustainable stock market volatility

In vitro bioactivities of Codonopsis javanica root extract from Kon Tum province, Vietnam

Dangshen Codonopsis javanica exhibits invaluable medicinal properties in herbal remedies; however, there has currently not been much specific analysis of the phytochemicals and bioactivities of this plant. The root ethanol extract of C. javanica contains substances such as saponins, phenolic acids, terpenoids, and alkaloids. It displays an antibacterial effect against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus cereus with the IC50 values of 150, 100, 150, and 90 μg/mL, respectively. The antioxidant capacity of the root extract was also observed with an IC50 value of 46.8 ± 6.8 μg/mL. Furthermore, the extract exhibits activity on human cancer cell lines HepG2 (IC50 = 83.6 ± 2.7 μg/mL) and MCF-7 (IC50 = 95.3 ± 2.3 μg/mL). Hence, this study provides the basic data for further research on the bioactivities of natural compounds of Dangshen C. javanica for the first time

THE AERODYNAMIC CHARACTERISTICS OF A SOFT TYPE AIRSHIP NEAR TO A SCREEN IN VIEW OF A PROPELLER JETS INFLUENCE

The results of numerical research of a soft type airship aerodynamic characteristics in subsonic flow of viscous gas are received for the airship locating near to a screen and having the working propellers. The influence of propeller rotation and relative distance of the airship to the screen on values of its aerodynamic normal and longitudinal forces, and also pitching moment is shown at various airship angles of attack

ĐA HÌNH GEN LEPTIN VÀ THYROGLOBULIN LIÊN QUAN ĐẾN TÍNH TRẠNG NĂNG SUẤT VÀ CHẤT LƯỢNG THỊT Ở TỔ HỢP BÒ LAI SENEPOL × LAI BRAHMAN NUÔI TẠI TỈNH THỪA THIÊN HUẾ

This study was conducted to evaluate the polymorphisms in the intron 2 of leptin (LEP) gene (g.1926C>T) and in the 5’UTR of thyroglobulin (TG) gene (g.422C>T) in Senepol × lai Brahman crossbred cows raised in Thua Thien Hue province. The results of evaluating LEP and TG gene polymorphisms on 30 DNA samples with the PCR-RFLP technique show that the LEP/Sau3AI gene is polymorphic in the Senepol × lai Brahman crossbred cows, with the A allele related to high production and reproduction traits as the dominant allele (0.92). Five over 30 cows carried allele B related to high-fat yield percentage, and all were raised in Dien Mon commune. In contrast, all 30 studied cows carried heterozygous TG/PsuI genotype (CT). More DNA samples should be analysed to confirm the polymorphism of the TG5/PsuI gene in this crossbred cattle in Thua Thien Hue province, and further selection is needed to increase the frequency of the T allele related to a high marbling score of beef. These results are informative for further breeding of Senepol × lai Brahman crossbred cows.Nghiên cứu này được thực hiện nhằm đánh giá đa hình đoạn intron 2 của gen Leptin (LEP) (g.1926C>T) và vùng 5’UTR của gen thyroglobulin (TG) (g.422C>T) ở tổ hợp bò lai Senepol × lai Brahman nuôi tại tỉnh Thừa Thiên Huế. Kết quả đánh giá đa hình gen LEP/Sau3AI và TG5/PsuI trên 30 mẫu DNA bằng kỹ thuật PCR-RFLP cho thấy có sự đa hình về kiểu gen LEP/Sau3AI; tần số alen A liên quan đến các tính trạng năng suất và sức sinh sản cao là chủ yếu (0,92). Năm trong số 30 con bò mang alen B liên quan đến tỷ lệ mỡ trong thân thịt cao được phát hiện ở xã Điền Môn. Ngược lại, cả 30 con bò khảo sát đều mang kiểu gen TG5/PsuI dị hợp tử (CT). Do đó, để xác định chính xác hơn tính đa hình của gen TG5/PsuI trên tổ hợp bò lai Senepol × lai Brahman, cần tăng số lượng mẫu khảo sát và tiếp tục chọn lọc để tăng tần số alen T liên quan đến chỉ số vân mỡ cao trong thịt bò. Các kết quả nghiên cứu này cung cấp những thông tin di truyền ở cấp độ phân tử đầu tiên trên tổ hợp bò lai Senepol × lai Brahman nuôi tại tỉnh Thừa Thiên Huế và là cơ sở cho những nghiên cứu chọn lọc tiếp theo nhằm nâng cao chất lượng bò thịt

Determinants of students’ behavior in using light rail transit in Hanoi

On November 6th, 2021, the first light rail transit (LRT) began operating in Vietnam after a decade of construction. This project aimed to alleviate traffic congestion in the road network of the Hanoi capital. However, despite the deployment of the transit service, passenger volume remains under-capacity, raising questions about how to encourage people, particularly young individuals, to use the new public transit. Hence, this study investigated students’ behavior in choosing the LRT as a means of transport. Statistical analysis of the questionnaire survey showed that the satisfaction level was the dominant factor affecting the mode choices of students. Besides, distance from home to school and LRT station accessibility significantly influenced students’ traveling behavior. These findings provide fundamental insight into young Vietnamese individuals’ behavior regarding a new transit service. We believe these outcomes would help support policy-makers and service providers in improving the LRT projects’ efficiency

Digital twins of robotic systems: increasing capability for industrial applications

Digital twin is one of the emerging areas of research and technology development and the enabling technologies of Smart Manufacturing and Industry 4.0. This study aims to develop and demonstrate a proof-of-concept prototype with a case study of the digital twin of a robotic system. The system has two main elements: the virtual element and the physical or the real element. The virtual element of system has been built based on the Unity platform, which is a cross-platform game engine developed by Unity Software Inc., and the physical element was built with the use of two servomotors and the NVIDIA® Jetson Nano™ Developer Kit. The virtual and the physical elements are connected and communicated via using the TCP socket protocol suite. A digital twin model of the ABB IRB 120 robot was successfully developed and demonstrated. The collected data include the joint angle position values of the physical and virtual models, and they are stored both locally and in the cloud for the future system development, which can be used as for minimizing the errors between the physical and virtual models of digital twins of robotic systems. The successfully developed digital twin model can be considered as the cost-effective solutions for demonstrating and evaluating potential applications of digital twins in industrial practices as well as in higher educations and research