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>

Distribution Status of Hybrid Types in Large Liver Flukes, Fasciola Species (Digenea: Fasciolidae), from Ruminants and Humans in Vietnam

Thi Bich Nga Nguyen,Nguyen Van De,Thi Kim Lan Nguyen,Huynh Hong Quang,Huong Thi Thanh Doan,Takeshi Agatsuma,Thanh Hoa Le 대한기생충학열대의학회 2018 The Korean Journal of Parasitology Vol.56 No.5

First Report on Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus Isolates in Children Admitted to Tertiary Hospitals in Vietnam

( Nguyen Thai Son ),( Vu Thi Thu Huong ),( Vu Thi Kim Lien ),( Do Thi Quynh Nga ),( Tran Thi Hai Au ),( Tang Thi Nga ),( Le Nguyen Minh Hoa ),( Tran Quang Binh ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.9

The extensive distribution of multidrug-resistant (MDR) methicillin-resistant Staphylococcus aureus (MRSA) poses a threat to healthcare worldwide. This study aimed to investigate the MDR and molecular patterns of MRSA isolates in children admitted to the two biggest tertiary care pediatric hospitals in northern and southern Vietnam. A total of 168 MRSA strains were collected to determine antibiotic susceptibility by minimum inhibitory concentration tests. Antibiotic-resistant genes, pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec (SCCmec) typing, and multilocus sequence typing were used for the molecular characterization of MRSA. Among the total strains, the MDR rate (51.8%) was significantly higher in the northern hospital than in the southern hospital (73% vs. 39%, p < 0.0001). The MDR-MRSA with the highest rates were “ciprofloxacin-erythromycin-gentamicin-tetracyclines” (35.6%), followed by “erythromycin-tetracycline-chloramphenicol” (24.1%), and “ciprofloxacin-erythromycin-gentamicin” (19.5%), showing an accumulative total of 79.3%. The most susceptible antibiotics were rifampicin (100%) and vancomycin (100%), followed by doxycycline (94.0%), meropenem (78.0%), and cefotaxime (75.0%). The SCCmecII strains showed greater resistance to gentamicin, ciprofloxacin, tetracycline, meropenem and cephalosporins compared with the other strains. The SCCmecII strains exhibited the highest rate in the tested genes (aacA/aphD: 55.2%, ermA/B/C: 89.7%, and tetK/M: 82.8%). ST5-SCCmecII was the predominant clone in the northern hospital, whereas SCCmecIVa was more pronounced in the southern hospital. In conclusion, our results raised concerns about the predominant MDR-MRSA strains in the pediatric hospitals in Vietnam. The north-south difference in the antibiotic resistance patterns and genetic structure of MRSA suggests different MRSA origins and various uses of antimicrobial agents between the two regions.

The Impact of Foreign Ownership and Management on Firm Performance in Vietnam

NGUYEN, Thi Xuan Hong,PHAM, Thu Huyen,DAO, Thi Nhung,NGUYEN, Thi Nga,TRAN, Thi Kim Ngoc Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.9

The human and capital resources from foreign investors are important sources of finance for developing countries. Foreign ownership can help the firm to raise funds for operations and the foreign management can help the firm expand the market and improve management. However, does this really happen to Vietnamese firm? To find the answer to that question, this paper examines the impact of foreign ownership and management on the financial performance of listed firms on Vietnam's stock market. The data collected include 427 listed firms in all fields over five years, from 2014 to 2018. The financial performance is measured by Tobin's Q, ROA and ROE. The study carried out testing of each model by the least squares method of Pool OLS, assessing random effects (REM) and evaluating fixed effects (FEM). The most effective model is the FEM model. The results show that the foreign ownership ratio and the size of the firm have a positive impact on the financial performance. The foreign management, the age of the firms, the liquidity and financial leverage have a negative impact on the financial performance. Based on the research results, the study proposes some recommendations to improve the financial performance of listed firms in Vietnam.

Advanced Magnetic Materials Produced by Using Rapid Quenching Technology

Nguyen Hoang Nghi,Nguyen Van Dung,Trinh Thi Thanh Nga,Bui Thi Khanh Nhung,Mai Thanh Tung,Nguyen Huu Tinh,Hoang Nhat Hieu,Bui Xuan Chien,Nguyen Thi Hong Tam 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.6

Amorphous alloys produced by using a rapid quenching technique are considered to be a precursor for producing nanosized and multiphase structures by precipitation (the top-down method). By using this technique, several new magnetic materials with different magnetic properties based on different physical mechanisms have been manufactured and investigated. Three new magnetic materials, a nanocrystalline soft magnetic material, a soft-hard permanent magnet and a Me-3d granular alloy with a GMR effect, what were prepared under local conditions, are presented and discussed in the experimental point of view. Amorphous alloys produced by using a rapid quenching technique are considered to be a precursor for producing nanosized and multiphase structures by precipitation (the top-down method). By using this technique, several new magnetic materials with different magnetic properties based on different physical mechanisms have been manufactured and investigated. Three new magnetic materials, a nanocrystalline soft magnetic material, a soft-hard permanent magnet and a Me-3d granular alloy with a GMR effect, what were prepared under local conditions, are presented and discussed in the experimental point of view.

Purchase Intention Towards Japanese Convenience Goods: A Cross-Sectional Study in Vietnam

Nga Thi Quynh NGUYEN,Duong Tuan NGUYEN,Quynh Thi Phuc NGUYEN 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.10

The primary purpose of this study is to identify determinants influencing Vietnamese consumers’ purchase intention towards Japanese convenience goods. The research model consisting of six factors affecting the dependent variable is proposed based on the Theory of Consumption Values and Theory of Perceived Value of purchase. This study employs a survey method in a convenient sampling method to collect data of target respondents. Data consisting of 180 samples was collected and analyzed using the SMARPLS3 software. The measurement model is assessed to confirm the validity and reliability of the construct, then hypotheses testing is performed with Bootstrapping analysis. The results demonstrated that five factors affect Vietnamese consumers’ purchase intention towards Japanese convenience goods, including the price of the product, quality of the product, functional value, emotional value, and conditional value. Major findings of this study suggest that the functional value that consumer perceives about Japanese convenience goods has the most significant relationship with their purchase intention, followed by the quality of the product and the price of the product. Besides, emotional value and conditional value have a moderate influence on consumers’ purchase intention. Whereas the influence of the epistemic value of the product on consumers’ purchase intention is insignificant in this presented study.

Cigarette Smoking among Adolescents aged 13-15 in Viet Nam and Correlates of Current Cigarette Smoking: Results from GYTS 2014 Data

Le, Thi Huong,Nga, Thi Thu Vu,Nguyen, Ngoc Dung,Le, Thi Thanh Xuan,Kim, Bao Giang,Phan, Thi Hai,Doan, Thu Huyen,Luong, Ngoc Khue,Nguyen, Tuan Lam,Hoang, Van Minh,Pham, Thi Quynh Nga Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.no.sup1

The aim of this paper is to report the rate of current and ever cigarette smoking and explore correlates of current cigarette smoking among adolescents aged 13-15 in Viet Nam. This analysis was derived from GYTS survey, which comprised of 3,430 adolescents aged 13-15, conducted in 2014 in 13 cities and provinces of Viet Nam. We calculated the weighted rates of current and ever cigarette smoking and reported patterns of smoking behavior. We also performed logistic regression to explore correlates of current cigarette smoking behavior. The weighted rate of ever cigarette smoking was 9.5% (95% confidence interval (CI): 8.5 %-10.5%), in which the weighted rate among males (15.4%; 95% CI: 13.6%-17.0%) was higher than that among females (4.2%; 95% CI: 3.3%-5.1%). The weighted rate of current cigarette smoking was relatively low at 2.5% (95%CI: 2.0%-3.0%) with higher weighted rate among males (4.9%; 95% CI: 3.8%-5.9%) compared to the corresponding figure among females (0.2%; 95% CI: 0.0 %-0.5%). Current cigarette smoking was significantly higher among males than females, in students aged 15 versus 13 years old, and in students who had several or all close friends smoking and students with daily observation of smoking at school. For greater smoking reduction outcomes, we recommend that tobacco interventions for adolescents should consider targeting more male students at older ages, establish stricter adherence to school-based banning of cigarette smoking, engage both smoking and nonsmoking adolescents and empower adolescents to resist peer smoking influence as well as changing their norms or beliefs towards smoking benefits.

Potential Development Of Homestay Tourism Types In Highlands - Vietnam

( Nguyen Thi Viet Nga ),( Le Thi Minh Thu ),( Vu Van Nam ) 한국문화관광학회 2016 문화관광연구 Vol.18 No.2

Homestay is a type of tourism that has been grown strongly in the world. This type of tourism brings the sustainable livelihood for social community. When experiencing the type of homestay tourism, visitors will be immersed in many activities of the community life, from that, visitors can discover (know) - understand - love the cultural values of the community more and more. So, to be able to develop successfully the type of homestay tourism, the essential requirement is that community must possess the different, unique cultural values so that they can bring fun, attractiveness for tourists. And the ethnic minorities in the Central Highlands - Vietnam satisfies this necessary condition. In this paper, we will analyze the key issues such as: the developing trend of homestay tourism in the world and in Vietnam; potentiality and actual development of homestay tourism in Highlands area; proposing some solutions to develop this kind of homestay tourism in the Highlands as a plan to contribute to the conservation, promotion and development of traditional cultural values of an regional Highlands ethnic communities in the contemporary society.

The Impact of Exchange Rate on Exports and Imports: Empirical Evidence from Vietnam

Nga Hong NGUYEN,Hat Dang NGUYEN,Loan Thi Kim VO,Cuong Quoc Khanh TRAN 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.5

The exchange rate is considered a tool improving the volume of exports and reducing imports. This paper aims to determine the impact of the exchange rate on exports and imports between Vietnam and the United States in the context of the trade war. The research uses Autoregressive Distributed Lag (ARDL) and Nonlinear Autoregressive Distributed Lag (NARDL) Model in the time-series data from 2010:1 to 2020:9. The ARDL’s results support that real exchange rate impact on export and import volumes, but less than the trade war. The trade war helps trade balance increase 0.35%, while the exchange rate increases trade balance 0.191% when the Vietnamese currency devalues 1% in the long run. In the short term, the real exchange rate makes the trade balance decrease. Therefore, the J curve exists between Vietnam and the U.S. The NARDL expresses that the exchange rate is asymmetric both in the short term and the long term. The findings of this study point to two important elements. Firstly, the exchange rate plays a minor role in exports and imports. Secondly, trade war plays a vital role in increasing exports and imports volume between two countries, and the J curve exists between the two countries.

The fig wax scale Ceroplastes rusci (Linnaeus) (Homoptera: Coccidae) in south-east Vietnam: Pest status, life history and biocontrol trials with Eublemma amabilis Moore (Lepidoptera: Noctuidae)

Nga Thi VU,Rod EASTWOOD,Chat Thi NGUYEN,Lam Van PHAM 한국곤충학회 2006 Entomological Research Vol.36 No.4

The fig wax scale Ceroplastes rusci (Linnaeus) is a serious pest of fruit trees in many countries. In the present study we investigated the extent of C. rusci infestation and the range of host species, particularly in fruit orchards, in south-east Vietnam. Captive populations of C. rusci were established to record life history parameters and to investigate the efficacy of an endemic predacious moth, Eublemma amabilis Moore, as a potential biocontrol agent. Heavy infestation of C. rusci (up to 100%) was recorded in soursop and other fruit orchards, and the culturally important Hoa Mai flower was also affected. Captive breeding trials found E. amabilis to be an efficient predator of C. rusci, but an unusual hyperactive trait in early instars of E. amabilis resulted in lower than expected survival rates.The implications of this trait in terms of the laboratory environment, augmentative release protocols and as a survival strategy are discussed.