Uptake of arsenic and heavy metals by native plants growing near Nui Phao multi-metal mine, northern Vietnam

Ha, Nguyen Thi Hoang,Ha, Nguyen Thi,Nga, Tran Thi Huyen,Minh, Nguyen Ngoc,Anh, Bui Thi Kim,Hang, Nguyen Thi An,Duc, Nguyen Anh,Nhuan, Mai Trong,Kim, Kyoung-Woong Elsevier 2019 Applied geochemistry Vol.108 No.-

<P><B>Abstract</B></P> <P>Phytoremediation is a plant-based, environment-friendly, and cost-effective technology that can be potentially used to remediate contaminated media. This study was conducted to evaluate the phytoextraction and phytostabilization potential, two common techniques of phytoremediation, of 21 plant species growing naturally at the largest tungsten (W) mine in Vietnam—the second largest production of W in the world. The average concentrations in different soil fractions were in the following order: residue > organically complexed, Fe- and Mn oxide-bound > carbonate bound > exchangeable. The total concentrations of arsenic (As), cadmium (Cd), copper (Cu), and zinc (Zn) in the soil varied by 34–3390, 4.87–81.6, 14.3–2080, and 21.9–370 mg/kg, respectively. The concentrations of As, Cd, Cu, and Zn in the shoots ranged 0.71–2400, 0.05–5.55, 4.81–249, and 13.3–380 mg/kg-DW, respectively. The concentrations of As and Cd in all soil samples and Cu in 70% of soil samples collected around the mine fluctuated within 2–227, 3–54, and up to 21-folds higher than the maximum allowable limit for agricultural soils in Vietnam (QCVN 03-MT:2015/BTNMT). The results indicated that hyperaccumulation levels (mg/kg-DW) were obtained for only As in <I>Pityrogramma calomelanos</I> (2400) and <I>Pteris vittata</I> L. (1860). Based on the recorded hyperaccumulation levels, translocation and accumulation factors, biomass, and fast growth of these plants, <I>P. calomelanos</I> and <I>P. vittata</I> were considered to be promising native plants for the phytoextraction of As contaminated soils. <I>Bidens pilosa</I> L. also has great potential for phytostabilization of mining soils contaminated with As and heavy metals.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Soils near multi-metal (W–F–Cu–Au–Bi) mine were contaminated with As, Cd, Cu. </LI> <LI> Arsenic in shoots were in order of Fern > Monocotyledonae > Dicotyledonae. </LI> <LI> <I>Pityrogramma calomelanos</I> and <I>Pteris vittata</I> L. suggested for phytoextraction of As. </LI> <LI> <I>Bidens pilosa</I> L. suggested for the phytostabilization of mining contaminated soils. </LI> </UL> </P>

Cultural Factors Affecting Tendency of Ethical Decision-Making by Accounting Students: An Empirical Study in Vietnam

Nga Thanh DOAN,Trang Thu TA,Ha Thi Thanh CHU,Anh Thi Quynh LE,May Thi LE,Tuan Hoang PHAM,Thao Thu VUONG 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.2

The purpose of this study is to look at the precise direction and magnitude of cultural elements such as education, gender, power distance, and risk-taking proclivity on ethical decision-making. Data was collected from 194 interviewees in three groups: general business students, accounting major students, and professional auditors in Vietnam. The path analysis is used to test the impact of cultural factors on ethical awareness, ethical judgment, and ethical intention in different dubious scenarios at the personal level as independent variables, intermediate variables, and moderating variables. The metric is the percentage of respondents who believe a particular behavior is unethical based on a set of ethical principles. The researchers used SPSS AMOS software to conduct a confirmatory factor survey to evaluate the convergent and discriminant validity of latent variables. The results show differences between the two groups of students and professionals on these measures, suggesting that all of the four factors have an effect on ethical decision-making. Based on research results, some recommendations are proposed related to the four factors to improve the ethics of future generations of auditors in Vietnam. This study also contributes to the theory of culture in particular and cultural interference in general in the field of accounting-auditing in Vietnam in the process of international integration.

Thermoneutral Housing Exacerbates Liver Fibrosis In Mice

( Nga Thi Ha ),( Ho Yeop Lee ),( Hyon-seung Yi ) 대한간학회 2020 춘·추계 학술대회 (KASL) Vol.2020 No.1

Aims: Thermoneutral condition has been had a significant impact on metabolic studies. The roles of brown adipose tissue (BAT) on metabolic disease including obesity or fatty liver is receiving increasing attention. Here, we investigated the impact of thermoneutral condition on hepatic fibrosis as well as the contribution of BAT on regulation liver fibrosis in mice. Methods: In this study, we used carbon tetrachloride (CCl4) induced liver fibrosis mouse model and hepatic stellate cells isolated from mice in order to checked fibrotic marker in mice livers housed under room temperature and thermoneutral condition for three weeks. We also compared the changes in the population of hepatic immune cells and the deposition of collagen in mice livers between two kinds of housing conditions. Furthermore, we investigated the effect of secreted factors from brown adipocytes-conditioned media on hepatic stellate cells (HSC) activation process. Results: Serum levels of liver injury and the expression of Col1a1, Acta2 and inflammatory cytokines were up-regulated in the liver of mice under thermoneutral condition compared to room temperature. Moreover, inactivation of BAT by thermoneutrality aggravated hepatic collagen deposition as well as promoted the activation of hepatic stellate cells during CCl4-induced liver fibrogenesis. In consistent with these findings, we also found that the population of infiltrating liver immune cells and pro-inflammatory cytokine-producing T cells was significantly increased in thermoneutral housing mice livers. Treatment of brown adipocytes-conditioned media attenuated HSC activation through down-regulated expression of a-SMA at day 4, day 7 and day 10 cultured HSC. Conclusions: These results suggest that BAT inactivation by thermoneutrality contributes to the activation of pro-inflammatory and pro-fibrotic pathways in CCl4-induced liver fibrogenesis. Secreted factors released from BAT have potential roles on inhibiting HSC activation. Thus, BAT-liver axis may serve as a potential therapeutic target for liver fibrosis.

Thermoneutrality Induces Interleukin-10 to Attenuate Liver Fibrosis

( Ha Thi Nga ),( Ji Sun Moon ),( Jingwen Tian ),( Ho Yeop Lee ),( Seok-hwan Kim ),( Young-sun Lee ),( Jae-han Jeon ),( Hyon-seung Yi ) 대한간학회 2021 춘·추계 학술대회 (KASL) Vol.2021 No.1

Colorimetric Determination of Singlet Oxygen Scavengers Using a Protein Photosensitizer

Miso Kim,Eun Hye Kim,Thi Hai Yen Pham,Tuan Anh Hoang Le,Thi Phuong Do,Thi Nga Nguyen,Thi Cuc Nguyen,Ha Phuong Trieu,Thi Thao Do,김영필 한국바이오칩학회 2020 BioChip Journal Vol.14 No.2

Despite the diverse roles of singlet oxygen ( 1 O2) in plants and animals, simple detection of 1 O2 has been limited due to technical difficulties. Here we report a colorimetric method for visualizing the generation and suppression of 1 O2 using a protein photosensitizer, mini singlet oxygen generator (miniSOG). Upon external light irradiation, miniSOG strongly produced 1 O2 and oxidized a universal chromogenic reagent, tetramethylbenzidine, leading to a rapid color change in solution. We used this finding to demonstrate the 1 O2 scavenging effects of well-known antioxidants and of natural compounds extracted from plants. Owing to its high usability and simplicity, our developed assay platform will be useful for screening potential scavengers for reactive oxygen species and will promote the development of various antioxidants.

The Effect of Non-Audit Services on Auditor Independence: Evidence from Vietnam

DOAN, Nga Thanh,PHAM, Cuong Duc,NGUYEN, Thuong Thi Uyen,VU, Mai Phuong,PHAM, Lam Ha Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.12

Independence is a factor which has a significant impact on auditing quality, especially in the recent times where the marketplace is increasingly demanding transparency. The independence of auditors is assessed based on the main criteria such as the reliability of the audit opinions, the accuracy, truthfulness of financial reports, and the objectivity in the opinions of the auditor. The study investigates the effects of non-audit services (NAS) on auditor independence in emerging economies such as Vietnam. Non-audit services include taxation services, management advisory services and outsourcing internal audit services. Based on previously relevant researches, the authors develop hypotheses and a regression model about non-audit services (independent variables) and audit independence (dependent variable). The research collects data by 5-scale Likert questionnaire. The findings indicate the relationship between NAS and auditor independence. Specifically, the results reveal two main factors that have influence on auditor independence, namely, taxation services and management advisory services. The results of our research can be considered as new findings and can be compared to previous researches in Vietnam, which establishes a new viewpoint about the relationship between the NAS and the independence of the auditor. This result can be implemented for countries or jurisdictions which are similar to Vietnam.

Tracking the establishment of local endemic populations of an emergent enteric pathogen

Holt, Kathryn E.,Thieu Nga, Tran Vu,Thanh, Duy Pham,Vinh, Ha,Kim, Dong Wook,Vu Tra, My Phan,Campbell, James I.,Hoang, Nguyen Van Minh,Vinh, Nguyen Thanh,Minh, Pham Van,Thuy, Cao Thu,Nga, Tran Thi Thu National Academy of Sciences 2013 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.110 No.43

<P><I>Shigella sonnei</I> is a human-adapted pathogen that is emerging globally as the dominant agent of bacterial dysentery. To investigate local establishment, we sequenced the genomes of 263 Vietnamese <I>S. sonnei</I> isolated over 15 y. Our data show that <I>S. sonnei</I> was introduced into Vietnam in the 1980s and has undergone localized clonal expansion, punctuated by genomic fixation events through periodic selective sweeps. We uncover geographical spread, spatially restricted frontier populations, and convergent evolution through local gene pool sampling. This work provides a unique, high-resolution insight into the microevolution of a pioneering human pathogen during its establishment in a new host population.</P>

Metabolite Changes during the Transition from Hyperthyroidism to Euthyroidism in Patients with Graves’ Disease

Ho Yeop Lee,Byeong Chang Sim,Ha Thi Nga,Ji Sun Moon,Jingwen Tian,Nguyen Thi Linh,Sang Hyeon Ju,Dong Wook Choi,Daiki Setoyama,이현승 대한내분비학회 2022 Endocrinology and metabolism Vol.37 No.6

Background: An excess of thyroid hormones in Graves’ disease (GD) has profound effects on systemic energy metabolism that are currently partially understood. In this study, we aimed to provide a comprehensive understanding of the metabolite changes that occur when patients with GD transition from hyperthyroidism to euthyroidism with methimazole treatment. Methods: Eighteen patients (mean age, 38.6±14.7 years; 66.7% female) with newly diagnosed or relapsed GD attending the endocrinology outpatient clinics in a single institution were recruited between January 2019 and July 2020. All subjects were treated with methimazole to achieve euthyroidism. We explored metabolomics by performing liquid chromatography-mass spectrometry analysis of plasma samples of these patients and then performed multivariate statistical analysis of the metabolomics data. Results: Two hundred metabolites were measured before and after 12 weeks of methimazole treatment in patients with GD. The levels of 61 metabolites, including palmitic acid (C16:0) and oleic acid (C18:1), were elevated in methimazole-naïve patients with GD, and these levels were decreased by methimazole treatment. The levels of another 15 metabolites, including glycine and creatinine,were increased after recovery of euthyroidism upon methimazole treatment in patients with GD. Pathway analysis of metabolomics data showed that hyperthyroidism was closely related to aminoacyl-transfer ribonucleic acid biosynthesis and branched-chain aminoacid biosynthesis pathways. Conclusion: In this study, significant variations of plasma metabolomic patterns that occur during the transition from hyperthyroidism to euthyroidism were detected in patients with GD via untargeted metabolomics analysis.

Factors Affecting the Internal Control System: A Case Study of Chemical Enterprises in Vietnam

Hoang Thanh NGO,Tung Dao NGUYEN,Nga Thuy Thi NGUYEN,Ha Ngoc DAO,Anh Phuong Tran VU 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.12

The article analyzes the impact of factors affecting the internal control system of chemical enterprises in Vietnam, providing more empirical evidence on factors affecting the system of internal control. Research data is collected in the form of face-to-face interviews and email interviews with managers and employees working in different positions, managers at all levels, chief accountants, and accountants of 52 chemical enterprises in Vietnam. The survey results collected 310 questionnaires. After eliminating the invalid questionnaires due to many blank cells, the authors chose to use 297 questionnaires. Quantitative research was carried out with SPSS 25 software. Research results show that Business Strategy, Organizational Structure, Organization’s perception of the instability of the external environment, and Organizational culture are the factors that positively affect the internal control system of chemical enterprises. This can be explained that, for chemical enterprises, Business strategy, Organizational structure, Organization’s perception of the instability of the external environment, and Good organizational culture will positively impact the internal control system of chemical enterprises. Based on the research results, the authors have proposed recommendations to enhance the effectiveness of the internal control system of chemical enterprises in Vietnam, thereby contributing to improving the performance of enterprises in the chemical Vietnamese.

The Influence of Leadership Style on Accountants' Commitment with Enterprise: An Empirical Study on Vietnamese FDI Firms

DO, Duc Tai,NGUYEN, Tien Hung,NGUYEN, Thi Hong Nga,HA, Hong Hanh,LE, Thi Tam Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.3

The research aims to examine the impact of leadership style on accountants' commitment with FDI firms in Vietnam based on theory of Bass and Avolio (2004). A survey with 110 accountants in FDI firms was conducted. The total of 110 respondents with full information were used for data entry and analysis. Through quantity methodology, we used Cronbach's Alpha, EFA and correlation analysis to determine the relationship between leadership style and three dependent variables including affective, normative and continuance commitment. The results showed that the leadership style had positive relationships with accountants' commitments. In particular, normative commitment with FDI firms of accountants is the most strongest. In addition, there is no statistically difference in the level of three commitments with FDI firms of accountants for three groups of job description. From the findings, this study suggests several recommendations to improve accountants' commitments such as intellectually stimulating, individualized consideration, inspirational motivation, idealized influence, and idealized influence behavior. The results are considered as a useful reference for establishing policies to attract talent personnel toward to sustainable development of firms. Commitment with the organization is a crucial factor to gain a competitive advantage and guide the success of organizations by satisfying customers, maintaining productivity and efficiency.