Detection of antidiabetic drugs used as adulterants in traditional herbal medicines and dietary supplements by various liquid chromatographic techniques

Dao Thi Cam Minh,Pham Thi Thanh Ha,Nguyen Thi Ha Oanh,Nguyen Xuan Hieu,Pham Thi Tam,Le Van Vu,Nguyen Thi Kieu Anh 한국분석과학회 2018 학술대회논문집 Vol.2018 No.5

Factors Influencing on Consumer's Decision on Vegetarian Diets in Vietnam

NGO, Vu Quynh Thi,VO, Thi Anh Dao,NGO, Anh Phung,NGUYEN, Do Mai Anh,LE, Minh Thu,TO, Thi Phuong Loan,NGUYEN, Thi Thuy Phi Korea Distribution Science Association 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.2

Recently, vegetarian diets have experienced a dramatic increase in popularity. The aim of the study is to explore and test the relationship between the factors influencing consumers' dietary decisions in Ho Chi Minh City, Vietnam. The questionnaire applied a five-point Likert scale to investigate factors that affect Ho Chi Minh City's citizens when they have a vegetarian diet. 497 respondents (68% female; 61.2% aged 18-22; 82.7% had regular vegetarian diets) living in Ho Chi Minh City took part in both online and offline surveys. The results were processed by SPSS 22.0 software. The reliability was checked by Cronbach Alpha and Exploratory factor analysis (EFA) to identify the underlying relationships between measured variables. The Correlation analysis was implemented to show how strong and degree of two variables are related to each other before the multivariate regression equation was analyzed. The result showed the Five factors that were motivating people in Ho Chi Minh City to decide on plant-based diets, such as Animal Welfare, Health, Religion, Mood, and Reference groups. The mood is the most influential variable that significantly influences people's food choices. Attitudes toward vegetarian diets are changing. Therefore, recognizing the trends in food consumption might help companies take advantage of investment opportunities and build their marketing strategies.

Impact of long COVID-19 on posttraumatic stress disorder as modified by health literacy: an observational study in Vietnam

Han Thi Vo,Tien Duc Dao,Tuyen Van Duong,Tan Thanh Nguyen,Binh Nhu Do,Tinh Xuan Do,Khue Minh Pham,Vinh Hai Vu,Linh Van Pham,Lien Thi Hong Nguyen,Lan Thi Huong Le,Hoang Cong Nguyen,Nga Hoang Dang,Trung 질병관리청 2024 Osong Public Health and Research Persptectives Vol.15 No.1

Objectives: The incidence of posttraumatic stress disorder (PTSD) has increased, particularly among individuals who have recovered from coronavirus disease 2019 (COVID-19) infection. Health literacy is considered a “social vaccine” that helps people respond effectively to the pandemic. We aimed to investigate the association between long COVID-19 and PTSD, and to examine the modifying role of health literacy in this association.Methods: A cross-sectional study was conducted at 18 hospitals and health centers in Vietnam from December 2021 to October 2022. We recruited 4,463 individuals who had recovered from COVID-19 infection for at least 4 weeks. Participants provided information about their sociodemographics, clinical parameters, health-related behaviors, health literacy (using the 12-item short-form health literacy scale), long COVID-19 symptoms and PTSD (Impact Event Scale-Revised score of 33 or higher). Logistic regression models were used to examine associations and interactions.Results: Out of the study sample, 55.9% had long COVID-19 symptoms, and 49.6% had PTSD. Individuals with long COVID-19 symptoms had a higher likelihood of PTSD (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.63–2.12; p<0.001). Higher health literacy was associated with a lower likelihood of PTSD (OR, 0.98; 95% CI, 0.97–0.99; p=0.001). Compared to those with long COVID-19 symptoms and the lowest health literacy score, those with long COVID-19 symptoms and a 1-point health literacy increment had a 3% lower likelihood of PTSD (OR, 0.97; 95% CI, 0.96–0.99; p=0.001).Conclusion: Health literacy was found to be a protective factor against PTSD and modified the negative impact of long COVID-19 symptoms on PTSD.

Magnetic Properties and Impedance Spectroscopic Studies of Multiferroic Bi<SUB>1-x</SUB>Nd<SUB>x</SUB>FeO₃ Materials

Dao Viet Thang,Du Thi Xuan Thao,Nguyen Van Minh 한국자기학회 2016 Journal of Magnetics Vol.21 No.1

Nd-doped BiFeO₃ materials were synthesized via a sol–gel method. The crystal structure, magnetic properties, and complex impedance spectroscopy of multiferroic Bi1-xNdxFeO₃ (BNFO) materials were investigated by Xray diffraction (XRD), Raman scattering, vibrating sample magnetometer (VSM), and complex impedance spectroscopy. Our results show that the lattice crystal constants (a, c) and the ratio c/a of BNFO materials decreased with increasing Nd concentration. All samples exhibited weak ferromagnetism at room temperature, and the magnetization of samples was enhanced by the presence of Nd<SUP>3+</SUP> ions. There was an enhancement in the spontaneous magnetization of BFO with increasing Nd concentration, which is attributable to the collapse of the spin cycloid structure.

Trifluralin in aquatic products: QuEChERS and Gas chromatography-tandem mass spectrometry for trace amount detection

Le-Thi Anh-Dao,Do Minh-Huy,Vo Hong-Phong,Nguyen Cong-Hau 한국분석과학회 2023 분석과학 Vol.36 No.5

In the present study, an analytical method was proposed for detecting trifluralin in aquatic products at trace concentrations. The method employed QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) and gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) as the sample preparation and measurement, respectively. The effect of the aqueous phase volume used in the QuEChERS was demonstrated, and the ratio of 10:10 (mL) between water and acetonitrile phase was used for 5 g of sample. Besides, dSPE using C18 and primary-secondary amine (PSA) was applied to remove the potential interferences from the food matrices, indicating no remarkable analyte loss. The linear range was built up from 0.50 μg L–1 to 3.0 μg L–1 (R2 = 0.9993). Other criteria, i.e., repeatability (RSDr = 0.86-1.96 %), reproducibility (RSDR = 1.09-2.01 %), and recovery (over 90 %), were in accordance with Appendix F of AOAC (2016) for method performance. Although no trifluralin was detected for the commercial samples (fish, shrimp, and breaded shrimp), the spiked samples performed favorable recoveries and precision.

Factors Affecting Enterprises that Apply the International Financial Report Standards (IFRS): A Case Study in Vietnam

NGUYEN, Thi Le Hang,LE, Tran Hanh Phuong,DAO, Nhat Minh,PHAM, Ngoc Toan Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.12

In the global trend toward economic integration, Vietnamese enterprises desire to attract investment and increase competitiveness in the global market, so they have been required to provide transparent, high-quality financial reports following the International Financial Reports Standards (IFRS). Based on the roadmap drawn by the Vietnam Ministry of Finance, the foreign-invested enterprises, listed enterprises and state-owned enterprises will be applying IFRS in 2030. However, some enterprises in Vietnam have applied IFRS in the presentation of financial statements at the request of related parties for a while. The main research objective of this paper focused on examining the factors affecting the implementation of IFRS in Vietnamese enterprises through descriptive statistics tools, Cronbach's Alpha testing, EFA and logistics regression analysis with the sample collected from 254 Vietnamese enterprises. The methodology in this research was the mixed qualitative and quantitative method. The results show that the higher the profitability, debt ratio and firm size of the enterprise, the more likely it is to apply IFRS. From the results of this study, the appropriate recommendations have been made to promote the implementation of IFRS by Vietnamese enterprises effectively and following the IFRS application roadmap of the Ministry of Finance of Vietnam.

Comparison of different colorimetric assays and application of the optimized method for determining the liberated fluoride contents in various tea extracts

Le-Thi Anh-Dao,Do Minh-Huy,Nguyen-Ho Thien-Trang,Nguyen Cong-Hau 한국분석과학회 2024 분석과학 Vol.37 No.2

The appropriate intake of fluoride (F–) is beneficial to human health; however, the over-consumption can result in various potentially harmful effects. This study compared different colorimetric reagents, i.e., aluminium-xylenol orange (Al-XO), zirconium-xylenol orange (Zr-XO), and zirconium-alizarin red S (Zr-ARS), for fluoride measurements by the UV-Vis, in terms of reaction mechanisms, method sensitivity, and interferences from aluminium and ferric ions. The colorimetric procedures were optimized, and the analytical methods were evaluated. The goodness of linearity (R2 > 0.998) was obtained for all three assays within the concentration range of 1.0-20.0 mg/L fluoride in deionized water, in which the method sensitivity followed the descending order of Zr-XO > Al-XO > Zr-ARS. The Zr-XO was applied for determining the fluoride in different tea extracts in water (90 °C and 60-minute-brewing) and black tea demonstrated the highest fluoride content (3.0-3.6 mg/L). The effects of brewing time and temperature on the release of fluoride in the tea extracts were also investigated, indicating these are critical factors for the fluoride extraction. This study highlighted the application potentials of the UV-Vis measurement as a simple, convenient, and cheap analytical approach and discussed different colorimetric reagents used for fluoride determination in tea extracts in the context that the UV-Vis spectrophotometers are commonly equipped in most laboratories.

Al₂O₃/SiON stack layers for effective surface passivation and anti-reflection of high efficiency n-type c-Si solar cells

Nguyen, Huong Thi Thanh,Balaji, Nagarajan,Park, Cheolmin,Triet, Nguyen Minh,Le, Anh Huy Tuan,Lee, Seunghwan,Jeon, Minhan,Oh, Donhyun,Dao, Vinh Ai,Yi, Junsin Institute of Physics 2017 Semiconductor science and technology Vol.32 No.2

<P>Excellent surface passivation and anti-reflection properties of double-stack layers is a prerequisite for high efficiency of n-type c-Si solar cells. The high positive fixed charge (<I>Q</I> <SUB>f</SUB>) density of N-rich hydrogenated amorphous silicon nitride (a-SiN<SUB>x</SUB>:H) films plays a poor role in boron emitter passivation. The more the refractive index (<I> <B>n</B> </I>) of a-SiN<SUB>x</SUB>:H is decreased, the more the positive <I>Q</I> <SUB>f</SUB> of a-SiN<SUB>x</SUB>:H is increased. Hydrogenated amorphous silicon oxynitride (SiON) films possess the properties of amorphous silicon oxide (a-SiO<SUB>x</SUB>) and a-SiN<SUB>x</SUB>:H with variable <I> <B>n</B> </I> and less positive <I>Q</I> <SUB>f</SUB> compared with a-SiN<SUB>x</SUB>:H. In this study, we investigated the passivation and anti-reflection properties of Al<SUB>2</SUB>O<SUB>3</SUB>/SiON stacks. Initially, a SiON layer was deposited by plasma enhanced chemical vapor deposition with variable <I> <B>n</B> </I> and its chemical composition was analyzed by Fourier transform infrared spectroscopy. Then, the SiON layer was deposited as a capping layer on a 10 nm thick Al<SUB>2</SUB>O<SUB>3</SUB> layer, and the electrical and optical properties were analyzed. The SiON capping layer with <I> <B>n</B> </I>?=?1.47 and a thickness of 70 nm resulted in an interface trap density of 4.74?=?10<SUP>10</SUP> cm<SUP>−2</SUP> eV<SUP>−1</SUP> and <I>Q</I> <SUB>f</SUB> of −2.59?=?10<SUP>12</SUP> cm<SUP>−2</SUP> with a substantial improvement in lifetime of 1.52 ms after industrial firing. The incorporation of an Al<SUB>2</SUB>O<SUB>3</SUB>/SiON stack on the front side of the n-type solar cells results in an energy conversion efficiency of 18.34% compared to the one with Al<SUB>2</SUB>O<SUB>3</SUB>/a-SiN<SUB>x</SUB>:H showing 17.55% efficiency. The short circuit current density and open circuit voltage increase by up to 0.83 mA cm<SUP>−2</SUP> and 12 mV, respectively, compared to the Al<SUB>2</SUB>O<SUB>3</SUB>/a-SiN<SUB>x</SUB>:H stack on the front side of the n-type solar cells due to the good anti-reflection and front side surface passivation.</P>

Visible light-driven photocatalytic degradation of doxycycline using ZnO/g-C₃N₄/biochar composite in aqueous solution

Nguyen Van Hung,Bui Thi Minh Nguyet,Nguyen Huu Nghi,Nguyen Minh Luon,Nguyen Ngoc Bich,Le Van Thanh Son,Nguyen Trung Kien,Dao Ngoc Nhiem,Nguyen Thanh Tuoi,Dinh Quang Khieu 대한환경공학회 2024 Environmental Engineering Research Vol.29 No.4

In the present work, ZnO/g-C₃N₄/biochar was prepared, and it was used for visible-light driven photocatalytic degradation of some colorants (methylene blue, rhodamine B, methyl orange) and some antibiotics (doxycycline, ciprofloxacin, amoxicilline). Biochar was prepared by pyrolysing Phragmites australis biomass. The ZnO/g-C₃N₄/biochar composite was synthesized with the alkaline hydrolysis method. The obtained materials were characterized by X-ray diffraction, scanning electron microscopy, transition electron microscopy, energy dispersive X-ray/elemental mapping, ultraviolet-visible-diffuse reflectance spectroscopy, photoluminescence spectroscopy, nitrogen adsorption/desorption isotherms and X-ray photoelectron spectroscopy. The results show that ZnO nanoparticles with a large surface area are highly dispersed on the g-C₃N₄ particle surface and biochar. The composite exhibits superior photocatalytic degradation ability toward doxycycline, a broad-spectrum antibiotic of the tetracycline compared with individual components (ZnO or g-C₃N₄) and satisfies stability after six treatment cycles. The kinetics and degradation mechanisms of doxycyline were also addressed. In addition, the present catalyst also exhibits the photocatalytic degradation of methylene blue, rhodamine B, methyl orange, ciprofloxacin and amoxicillin in visible-light regions.

Highly effective adsorption of organic dyes from aqueous solutions on longan seed-derived activated carbon

Nguyen Van Hung,Bui Thi Minh Nguyet,Nguyen Huu Nghi,Nguyen Mau Thanh,Nguyen Duc Vu Quyen,Vo Thang Nguyen,Dao Ngoc Nhiem,Dinh Quang Khieu 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.3

In this study, longan seeds - an agricultural by-product was used to fabricate activated carbon (LSAC) through two-step pyrolysis with pre-carbonization at low temperature in the first step and then activation by H3PO4. LSAC with large surface area and porous structure exhibits an excellent capacity of absorption towards both cationic dyes (methylene blue (MB), rhodamine-B (RhB)) and anionic dyes (methyl orange (MO), congo red (CR)). Experimental data can be described well by the pseudo-second kinetic model. The maximum adsorption capacity based on Langmuir isotherm model was found as 502.84; 397.77; 464.66 and 350.64 mg.g−1 for MB, RhB, MO and CR, respectively. The adsorption of MB, RhB and CR on LSAC is spontaneous and endothermic, while that for MO is spontaneous but exothermic. Furthermore, the adsorption mechanism of dyes on LSAC was also studied showing that it can occur by electrostatic interaction, hydrogen bonding, the filling of pores involving the interaction between dye ions with specific functional groups such as –OH, –COOH, –NH2 and –PO43− on the LSAC surface. These results suggest that LSAC material may be envisaged as a promising adsorbent for treatment of wastewater in textile industries.