Two new species of Camellia (Theaceae) from Vietnam

Lieu Thi Nguyen,Ninh Tran,Uematsu CHIYOMI,Katayama HIRONORI,Dung Van Luong,Son Thanh Hoang,Ky Danh NGUYEN,Hung Viet NGUYEN,Toan Canh THAI 한국식물분류학회 2018 식물 분류학회지 Vol.48 No.2

Two new species of Camellia (Theaceae) are described from Vietnam: Camellia vuquangensis Luong, Tran & L. T. Nguyen and Camellia hatinhensis Luong, Tran & L. T. Nguyen. The new taxa were col- lected from Vu Quang National Park in the center of Vietnam. The new finds are morphologically dissimilar to all known Camellia species. Recent Camellia discoveries have increased the number of species recorded in Viet- nam from 50 to 75, making Vietnam a center of diversity and a crucial area for more research into the diversity and distributions of Camellia.

Parenchymal-sparing anatomical hepatectomy based on portal ramification of the right anterior section: A prospective multicenter experience with short-term outcomes

Truong Giang Nguyen,Thanh Khiem Nguyen,Ham Hoi Nguyen,Hong Son Trinh,Tuan Hiep Luong,Minh Trong Nguyen,Van Duy Le,Hai Dang Do,Kieu Hung Nguyen,Van Minh Do,Quang Huy Tran,Cuong Thinh Nguyen 한국간담췌외과학회 2024 Annals of hepato-biliary-pancreatic surgery Vol.28 No.1

Backgrounds/Aims: Parenchymal-sparing anatomical hepatectomy (Ps–AH) based on portal ramification of the right anterior section (RAS) is a new technique to avoid unnecessarily transecting too much liver parenchyma, especially in cases of major anatomical hepatectomy. Methods: We prospectively assessed 26 patients with primary hepatic malignancies having undergone major Ps–AH based on portal ramification of the RAS from August 2018 to August 2022 (48 months). The perioperative indications, clinical data, intra-operative index, pathological postoperative specimens, postoperative complications, and follow-up results were retrospectively evaluated. Results: Among the 26 patients analyzed, there was just one case that had intrahepatic cholangiocarcinoma The preoperative level of α– Fetoprotein was 25.2 ng/mL. All cases (100%) had Child–Pugh A liver function preoperatively. The ventral/dorsal RAS was preserved in 19 and 7 patients, respectively. The mean surgical margin was 6.2 mm. The mean surgical time was 228.5 minutes, while the mean blood loss was 255 mL. In pathology, 5 cases (19.2%) had microvascular invasion, and in the group of HCC patients, 92% of all cases had moderate or poor tumor differentiation. Six cases (23.1%) of postoperative complications were graded over III according to the Clavien–Dindo system, including in three patients resistant ascites or intra-abdominal abscess that required intervention. Conclusions: Parenchymal-sparing anatomical hepatectomy based on portal ramification of the RAS to achieve R0-resection was safe and effective, with favorable short-term outcomes. This technique can be used widely in clinical practice.

Determinants Influencing Housing-Option Decision of Gen Y: The Case of Vietnam

Ha Thu LUONG(Ha Thu LUONG ),Dung Manh TRAN(Dung Manh TRAN ),Dan Linh Ngoc NGUYEN(Dan Linh Ngoc NGUYEN ),Van Bao NGUYEN(Van Bao NGUYEN ),Anh Thuc LE(Anh Thuc LE ),Hieu Van PHAM(Hieu Van PHAM ) 한국유통과학회 2023 유통과학연구 Vol.21 No.7

Large Magnetocaloric Effect above 300 K and Magnetoresistance in (La0.5Pr0.5)1-xPbxMnO3 Perovskites

Nguyen Chau,Duong Thi Hanh,Bui Cong Tinh,Nguyen Hoang Luong,Nguyen Duc Tho,Nguyen Hoang Hai 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.5

Perovskite compounds (La0.5Pr0.5)₁- xPbxMnO₃ (x = 0.1 - 0.5) with orthorhombic structure were prepared by using a solid-state reaction technique. In the studied samples, the spin-glass-like state occurs at low temperatures and the Curie temperature, Tc, increases from 170 K (x = 0.1) to 336 K (x = 0.5) because of a strong double exchange. The magnetic entropy change, │△Sm│, reached its largest value of 2.06 J/kg·K at △H = 13.5 kOe for the sample with x = 0.4 (Tc = 323 K). Due to the large │△Sm│ and high Tc, these materials are suggested for use as active magnetic refrigerants for magnetic refrigeration technology at temperatures above room temperature. While the conductivity of the samples with x = 0.1 and 0.2 exhibits only a semiconducting behavior over the whole measured temperature range, there is insulator-metallic phase transition on the R(T) curves of the samples with x = 0.3 - 0.5. The magnetoresistance of the samples was measured and large values for MR were found. Perovskite compounds (La0.5Pr0.5)₁- xPbxMnO₃ (x = 0.1 - 0.5) with orthorhombic structure were prepared by using a solid-state reaction technique. In the studied samples, the spin-glass-like state occurs at low temperatures and the Curie temperature, Tc, increases from 170 K (x = 0.1) to 336 K (x = 0.5) because of a strong double exchange. The magnetic entropy change, │△Sm│, reached its largest value of 2.06 J/kg·K at △H = 13.5 kOe for the sample with x = 0.4 (Tc = 323 K). Due to the large │△Sm│ and high Tc, these materials are suggested for use as active magnetic refrigerants for magnetic refrigeration technology at temperatures above room temperature. While the conductivity of the samples with x = 0.1 and 0.2 exhibits only a semiconducting behavior over the whole measured temperature range, there is insulator-metallic phase transition on the R(T) curves of the samples with x = 0.3 - 0.5. The magnetoresistance of the samples was measured and large values for MR were found.

Effect of salicylic acid and yeast extract on curcuminoids biosynthesis gene expression and curcumin accumulation in cells of Curcuma zedoaria

Nguyen Hoang Loc,Truong Thi Phuong Lan,Nguyen Duc Huy,Nguyen Ngoc Luong,Hoang Tan Quang,Trinh Huu Tan,Le Thi Anh Thu,Nguyen Xuan Huy 한국식물생명공학회 2019 JOURNAL OF PLANT BIOTECHNOLOGY Vol.46 No.3

The aim of this study is to evaluate the effect of yeast extract (YE) and salicylic acid (SA) on the expression of curcuminoid-biosynthesis genes (CzDCS and CURS1-3), and accumulation of curcumin in Curcuma zedoaria cell cultures. The results showed that, in cells treated with YE or SA, the expression levels of curcuminoid genes were 1.14- to 3.64-fold higher than the control (untreated cells), in which the YE exhibited a stronger effect in comparison with SA. Curcumin accumulation also tended to be similar to gene expression, curcumin contents in YE- or SA-treated cells were 1.61- to 2.53-fold higher than the control. The SA treatment at the fifth day of culture stimulated the curcumin accumulation and expression in all four genes compared to that at the beginning. While the YE treatments gave different results, the CzCURS1 and CzCURS3 genes were expressed strongly in cells that were treated at the beginning. However, the CzDCS and CzCURS2 genes showed the opposite expression pattern, they were activated strongly in the treatments at day five of the culture. However, the content of curcumin reached its maximum value on the fifth day of culture in all investigations.

Applications of Magnetite Nanoparticles for Water Treatment and for DNA and Cell Separation

Nguyen Hoang Hai,Nguyen Chau,Nguyen Hoang Luong,Nguyen Thi Van Anh,Phan Tuan Nghia 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.3

Magnetic nanoparticles with a diameter of 15 nm prepared by using the coprecipitation method have been applied to enforce the sedimentation of the solid waste, to adsorb the arsenic ions in water, to increase the DNA concentration by using a magnetic eld for the electrochemical DNA sensor and to separate the helper CD4+ T cells to determine the number of the cells in blood. A combination of magnetic nanoparticles and alum makes the solid waste in water under a magnetic field aggregate a dozen times faster than under the gravity alone. A concentration of 0.1 mg/l of arsenic in water was reduced to a value lower than the permissible concentration of 0.01 mg/l after few minutes of stirring. The particles functionalized with 3-aminopropyl triethoxysilane were used to enrich the DNA of the Herpes virus, which extended the sensitivity of an electrochemical sensor down to a concentration lower than nM/l. The particles coated with fluorescent-labeled antiCD4 antibody were used to count the helper CD4+ T cells. The fluorescence signals of the particle/cell system were two times stronger than those of the uorescence antiCD4 cell system. This can be used for the treatment of an HIV-infected patient with a simple fluorescent microscope. Magnetic nanoparticles with a diameter of 15 nm prepared by using the coprecipitation method have been applied to enforce the sedimentation of the solid waste, to adsorb the arsenic ions in water, to increase the DNA concentration by using a magnetic eld for the electrochemical DNA sensor and to separate the helper CD4+ T cells to determine the number of the cells in blood. A combination of magnetic nanoparticles and alum makes the solid waste in water under a magnetic field aggregate a dozen times faster than under the gravity alone. A concentration of 0.1 mg/l of arsenic in water was reduced to a value lower than the permissible concentration of 0.01 mg/l after few minutes of stirring. The particles functionalized with 3-aminopropyl triethoxysilane were used to enrich the DNA of the Herpes virus, which extended the sensitivity of an electrochemical sensor down to a concentration lower than nM/l. The particles coated with fluorescent-labeled antiCD4 antibody were used to count the helper CD4+ T cells. The fluorescence signals of the particle/cell system were two times stronger than those of the uorescence antiCD4 cell system. This can be used for the treatment of an HIV-infected patient with a simple fluorescent microscope.

Knowledge and Attitude Towards Tobacco Smoking among 13-15 Year-Old School Children in Viet Nam - Findings from GYTS 2014

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

Studies have shown that smoking is a learnt behavior, often initiated during adolescence. This paper aims to describe tobacco-related knowledge, attitude and associations among school adolescents aged 13-15 with exposure to anti-smoking information. Using data from the Global Youth Tobacco Survey (GYTS) in Viet Nam, 2014, knowledge was measured through 4 questions about tobacco use, and attitude was assessed through 3 questions on personal, social and environmental aspects. Students giving most anti-tobacco responses to all questions were considered as having correct knowledge or appropriate attitude or both. Access to anti-smoking information was determined by exposure to any media messages on tobacco control during the past 30 days and teaching in school about the danger of tobacco use during the past 12 months. A substantial percentage of students thought that being near others who smoke might be harmful to them and smoking is harmful to health (89.4% and 89.6% respectively). However, only 46.4% reported that it is definitely difficult to quit smoking and 66.9% thought that smoking for only 1 or 2 years, once stopped, is harmful to health. Slightly more than half of the respondents reported appropriate attitude that young smokers have fewer friends than others and smoking makes them less attractive and less comfortable at social events. Noticing anti-smoking messages in the media together with having lessons in school about the dangers of tobacco substantially increased the likelihood of having correct knowledge, appropriate attitude and both. Despite relatively high awareness about smoking harms, effective educational communication is still highly needed to improve the level of comprehensive knowledge and an appropriate attitude regarding tobacco use.

Continuous Behavior of Using Food Delivery Mobile Applications in Vietnam after Covid-19 Pandemic

Ha Thu LUONG(Ha Thu LUONG ),Nhi Lan DAO(Nhi Lan DAO ),Trang Thu NGUYEN(Trang Thu NGUYEN ),Uyen Thu Thi LA(Uyen Thu Thi LA ),Na Thi Le TRAN(Na Thi Le TRAN ),Hoa Thi DUONG(Hoa Thi DUONG ) 한국유통과학회 2023 유통과학연구 Vol.21 No.3

Purpose: During and after Covid-19 pandemic, technology has emerged as a key factor in supporting the recovery of the economy and the rise of living standards. This study examines seven factors affecting the intention of food delivery apps usage, which include Performance Expectancy, Effort Expectancy, Social Influence, Hedonic Motivation, Price Value, and Habit, and how much influence they have on the customers' behavioral continuance of food delivery apps after Covid-19 Pandemic. Research methodology: This research is a quantitative descriptive research with 473 qualified respondents from 550 respondents collected. Besides using the UTAUT2 model (Venkatesh et al., 2012), Information Quality was added to give a better explanation for the consumers’ intention towards continuance behavior using food delivery apps. The collected data is then processed using SPSS 22.0. Results: Habit factors and Information Quality factors have significant positive effects on promoting food delivery apps usage intention, which in turn influences continuance behavior. In addition, Habit factors and Information Quality factors together have an effect of 48.57% on Behavioral Intention. Conclusion: The result proves that positive habits and food information quality can increase the usage intention towards the behavioral continuance of consumers. Higher usage frequency can be improved by increasing these two factors.

Enhancing Removal of Acid Orange II by Heterogeneous Catalytic Ozonation Using ZnO Nanoparticles-Modified Fly Ash Composite

Hoang Van Hung,Chu Thi Hong Huyen,Nguyen Thi Dong,Nguyen Thi Hong Vien,Nguyen Thu Huyen,Luu Thi Cuc,Van Huu Tap,Nguyen Hoang,Duong Dinh Tuan,Nguyen Van Huu Luong 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.5

In this study, heterogeneous catalytic ozonation using fl y ash (FA) modifi ed ZnO nanoparticles to the decolorization of acid orange II (AOII) was studied. The combination of ZnO and fl y ash via an incipient wetness impregnation method to form ZOFA composites created a synergistic eff ect that led to effi cient catalytic ozonation activity towards AOII degradation and decolorization compared with individual ozonation processes. From the experimental results, ZOFA composite with the optimal weight ratio between ZnO NPs and FA was 20 wt% (denoted as ZOFA-20) that exhibited outstanding catalytic ozonation activity. Moreover, through other investigations including initial pH conditions and catalyst dosage, AOII could be eff ectively and optimally eliminated by 0.5 g of ZOFA-20 with an initial pH value of 11. The corresponding k value was measured as 0.248 min −1 with a maximum TOC removal content of 77.27%. Besides, ZOFA-20 could show high catalytic ozonation activity even at highly concentrated AOII concentrations while it could also retain its excellent stability and reusability over 5 continuous AOII removal cycles. From the experimental and electron paramagnetic resonance (EPR) results, hydroxyl radical ( · OH) was the main active species during the catalytic ozonation of AOII. The present study provides a promising approach to prepare novel composite-based fl y ash that would be applicable for removing azo dye and other dye pollutants in water via a catalytic ozonation strategy.

Effects of Job Satisfaction on Organizational Commitment and Turnover Intention Among Vietnamese Employees in Foreign Direct Investment Enterprises

Thi Phuong Diu TRAN(Thi Phuong Diu TRAN ),Thi Van Khanh NGUYEN(Thi Van Khanh NGUYEN ),Thanh Quang DO3(Thanh Quang DO3 ),Cong Nghiep NGUYEN(Cong Nghiep NGUYEN ),Thu Thuy LUONG(Thu Thuy LUONG ) 한국유통과학회 2022 유통과학연구 Vol.20 No.10

Purpose: This article focuses on exploring the associations between job satisfaction, organizational commitment, and turnover intention. Specifically, this study estimates the impacts of Vietnamese employees’ job satisfaction on their organizational commitment and turnover intention in FDI enterprises. Research design, data and methodology: The measures are adapted from previous studies to develop a questionnaire with a seven-point Likert scale. The dataset is directly collected from 227 respondents who are employees at FDI enterprises situated in the North of Vietnam. The dataset is analyzed by quantitative approaches using SPSS 24.0 and AMOS 24.0. Results: The results show that while turnover intention is positively correlated with monthly income, it is negatively correlated with job satisfaction and organizational commitment. Also, organizational commitment is positively associated with job satisfaction among employees at FDI enterprises in Vietnam. Conclusions: The findings of this study will serve as useful references for administrators of FDI enterprises and policymakers to promote employees’ job satisfaction and retain skilled employees.