Examining Customers' Continuance Intentions towards E-wallet Usage: The Emergence of Mobile Payment Acceptance in Vietnam

PHUONG, Nguyen Ngoc Duy,LUAN, Ly Thien,DONG, Vu Van,KHANH, Nguyen Le Nhat Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.9

The purpose of the research is to identify antecedents of mobile wallet continuance intention in Vietnam. A self-administered questionnaire was distributed to collect data from a total of 276 respondents. Partial least squares structural equation modeling was employed for analyzing the data. Five mobile wallet features - mobile application quality, mobile wallet familiarity, situational normality, payment security, and feedback mechanism - are introduced as fundamental elements, which influence customer' continuance intention to use mobile wallet in Vietnam. The results indicate that mobile quality application and familiarity can significantly influence perceived ease-of-use (PEOU) and perceived usefulness (PU), but situational normality has an impact only on PEOU. PEOU and PU are positively related to satisfaction. On the other hand, payment security and feedback mechanism affect positively customer' trust. As a result, the positive effects that satisfaction and trust have on electronic wallet continuance intention are confirmed. The findings can be used to advise mobile wallet providers to improve their platform design and services to retain users. As a theoretical contribution, this study combines the Technology Acceptance Model, Unified Theory of Acceptance and Use of Technology to investigate the key determinants on continuance intention in the context of electronic wallet in Vietnam.

The Impact of Extrinsic Work Factors on Job Satisfaction and Organizational Commitment at Higher Education Institutions in Vietnam

Phuong Ngoc Duy NGUYEN,Linh Le Khanh NGUYEN,Dong Nguyen Thanh LE 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.8

The purpose of this study is to explore the link between job satisfaction and organizational commitment at higher education institutions (HEIs) in emerging countries such as Vietnam and to determine extrinsic work factors that influence job satisfaction. Higher education is critical for socio-economic growth and the overall development of each country. Hence, an understanding of what motivates employees’ actions and attitudes should be obtained before determining the extent of employee satisfaction. The conceptual model was developed by incorporating job satisfaction-related variables, their relationships, and the impact of job satisfaction on organizational commitment. An empirical study was conducted on a study sample of public and private universities, with 316 academics and non-academic employees surveyed. The current study employed the partial least squares structural equation modeling to test the proposed hypotheses. The results reveal a positive and significant relationship between job satisfaction and organizational commitment. The findings confirm that extrinsic work factors (job itself, supervision, working conditions, payment, and reward and recognition) have a positive and significant relationship with job satisfaction. Furthermore, the study indicates that employees at HEIs who have a high level of ability utilization and supervisor support are more likely to be satisfied with their jobs.

A study on emission and fuel consumption of motorcycles in idle mode and the impacts on air quality in Hanoi, Vietnam

Yen-Lien T. Nguyen,Anh-Tuan Le,Khanh Nguyen Duc,Vinh Nguyen Duy,Cong Doan Nguyen 서울시립대학교 도시과학연구원 2021 도시과학국제저널 Vol.25 No.4

This study aims to develop the models of emission and fuel consumption during idling of motorcycles (MCs) in Hanoi, including the unsteady and steady idling stages. Five MC models commonly used in Hanoi were selected to measure the instantaneous emission and fuel consumption rates under the controlled conditions at the laboratory conditions. The instantaneous emission and fuel consumption models during idling were developed for the test MCs in the unsteady idling stage. The R2 of obtained models are higher than 0.9. The average emission and fuel consumption rates in the steady idling stages were determined. The average idling emissions of pollutants CO, CO2, HC and NOx were 60.9, 534.3, 10.3 and 1.8 g/h, respectively. The average fuel loss during idling is around 180 g/h. The emission released from the MC fleet in Hanoi during idling was estimated for the year 2018. The total idling emissions from the MC fleet of 3.9 million vehicles in the year 2018 of CO, CO2, HC and NOx were 6.5, 57.1, 1.1 and 0.2 kt, respectively. The total fuel loss during idling of the MC fleet in 2018 was ∼19.3 kt. The air pollutants eliminated in the idle mode as CO, CO2, HC and NOx contributed 2.23%, 3.19%, 1.14% and 1.03%, respectively, of the total emission from the MC fleet in Hanoi.

Methiopropamine, a methamphetamine analogue, produces neurotoxicity via dopamine receptors

Nguyen, Phuong-Tram,Dang, Duy-Khanh,Tran, Hai-Quyen,Shin, Eun-Joo,Jeong, Ji Hoon,Nah, Seung-Yeol,Cho, Min Chang,Lee, Yong Sup,Jang, Choon-Gon,Kim, Hyoung-Chun Elsevier Pub. Co 2019 Chemico-biological interactions Vol.305 No.-

<P><B>Abstract</B></P> <P>Methiopropamine (MPA) is structurally categorized as a thiophene ring-based methamphetamine (MA) derivative. Although abusive potential of MPA was recognized, little is known about the neurotoxic potential of MPA up to now. We investigated whether MPA induces dopaminergic neurotoxicity, and whether MPA activates a specific dopamine receptor. Here, we observed that treatment with MPA resulted in dopaminergic neurotoxicity in a dose-dependent manner. MPA treatment potentiated oxidative parameters (i.e., increases in the level of reactive oxygen species, 4-hydroxynonenal, and protein carbonyl), M1 phenotype-related microglial activity, and pro-apoptotic property (i.e<I>.,</I> increases in Bax- and cleaved caspase-3-expressions, while a decrease in Bcl-2-expression). Moreover, treatment with MPA resulted in significant impairments in dopaminergic parameters [i.e., changes in dopamine level, dopamine turnover rate, tyrosine hydroxylase (TH) levels, dopamine transporter (DAT) expression, and vesicular monoamine transporter-2 (VMAT-2) expression], and in behavioral deficits. Both dopamine D1 receptor antagonist SCH23390 and D2 receptor antagonist sulpiride protected from these neurotoxic consequences. Therefore, our results suggest that dopamine D1 and D2 receptors simultaneously mediate MPA-induced dopaminergic neurodegeneration in mice via oxidative burdens, microgliosis, and pro-apoptosis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MPA-induced initial oxidative burdens are prerequisite for neurotoxic consequences. </LI> <LI> Dopamine receptors facilitate microglial, and proapoptotic changes induced by MPA. </LI> <LI> Dopamine receptors mediate dopaminergic impairments induced by MPA. </LI> <LI> Microglia, but not astroglia, may be the neurotoxic target against MPA insult. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Role of dopamine D1 receptor in 3-fluoromethamphetamine-induced neurotoxicity in mice

Nguyen, Phuong-Tram,Shin, Eun-Joo,Dang, Duy-Khanh,Tran, Hai-Quyen,Jang, Choon-Gon,Jeong, Ji Hoon,Lee, Yu Jeung,Lee, Hyo Jong,Lee, Yong Sup,Yamada, Kiyofumi,Nabeshima, Toshitaka,Kim, Hyoung-Chun Elsevier 2018 Neurochemistry International Vol.113 No.-

<P><B>Abstract</B></P> <P>3-Fluoromethamphetamine (3-FMA) is an illegal designer drug of methamphetamine (MA) derivative. Up to date, little is known about the neurotoxic potential of 3-FMA. In the present study, we investigated the role of dopamine receptors in neurotoxicity induced by 3-FMA in comparison with MA (35 mg/kg, i.p.) as a control drug. Here we found that 3-FMA (40, 60 or 80 mg/kg, i.p.) produced mortality in a dose-dependent manner in mice. Treatment with 3-FMA (40 mg/kg, i.p.) resulted in significant hyperthermia, oxidative stress and microgliosis (microglial differentiation into M1 phenotype) followed by pro-apoptotic changes and the induction of terminal deoxynucleotidyl transferase dUDP nick end labeling (TUNEL)-positive cells. Moreover, 3-FMA significantly produced dopaminergic impairments [i.e., increase in dopamine (DA) turnover rate and decreases in DA level, and in the expression of tyrosine hydroxylase (TH), dopamine transporter (DAT), and vesicular monoamine transporter 2 (VMAT-2)] with behavioral impairments. These dopaminergic neurotoxic effects of 3-FMA were comparable to those of MA. SCH23390, a dopamine D1 receptor antagonist, but not sulpiride, a dopamine D2 receptor antagonist significantly attenuated 3-FMA-induced neurotoxicity. Although both SCH23390 and sulpiride attenuated MA-induced dopaminergic neurotoxicity, sulpiride is more effective than SCH23390 on the dopaminergic neurotoxicity. Interestingly, SCH23390 treatment positively modulated 3-FMA-induced microglial activation (i.e., SCH23390 inhibited M1 phenotype from 3-FMA insult, but activated M2 phenotype). Therefore, our results suggest that the activation of dopamine D1 receptor is critical to 3-FMA-induced neurotoxicity, while both dopamine D1 and D2 receptors (dopamine D2 receptor > dopamine D1 receptor) mediate MA-induced dopaminergic neurotoxicity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> 3-FMA facilitates mortality in a dose-dependent manner. </LI> <LI> 3-FMA-induced initial oxidative burdens are prerequisite for the neurotoxicity. </LI> <LI> D1R facilitates microglial and pro-apoptotic changes induced by 3-FMA. </LI> <LI> D1R mediates dopaminergic impairments induced by 3-FMA. </LI> <LI> The neurotoxicity induced by 3-FMA are comparable to that induced by MA. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Orodispersible film incorporating nanoparticulate loratadine for an enhanced oral bioavailability

Van Nguyen Khanh,Dang Thu Kim,Vu Linh Thi Dieu,Ha Nhan Thi,Truong Hieu Duy,Tran Tuan Hiep 한국약제학회 2023 Journal of Pharmaceutical Investigation Vol.53 No.3

Purpose Loratadine (LOR), a commonly prescribed antihistamine, has low water solubility but high permeability. In this study, an orodispersible film incorporating the nanoparticulate loratadine was prepared to enhance the oral bioavailability of a poorly water-soluble drug. Methods Nanoparticulate loratadine was formulated using the antisolvent precipitation method and optimized by a singlefactor design based on the particle size and polydispersity index. The optimal formulation was spray-dried and characterized by powder X-ray diffraction and differential scanning calorimetry. Nanoparticulate loratadine was loaded into an orodispersible film using a solvent casting method. Results In the dissolution tests, the nanoparticulate loratadine-loaded orodispersible film exhibited a 6.5-fold higher dissolution rate than the pure loratadine-loaded film and a similar dissolution rate compared to the commercialized orodispersible tablet, Loratadine SPM. In pharmacokinetic studies conducted on rats, the maximum concentration (Cmax) and area under the curve of the plasma concentration–time profile from 0 to 24 h (AUC 0-24 h) of the nanoparticulate loratadine-loaded orodispersible film significantly increased 1.8-fold and 5.8-fold, respectively. The elimination half-life (t1//2) increased 5.1-fold compared to the loratadine-loaded counterpart. Conclusion These results suggest the potential of orodispersible films to improve the oral bioavailability of poorly watersoluble drugs and promote compliance in pediatric and geriatric patients.

Using Syntax and Shallow Semantic Analysis for Vietnamese Question Generation

Phuoc Tran,Duy Khanh Nguyen,Tram Tran,Bay Vo 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.10

This paper presents a method of using syntax and shallow semantic analysis for Vietnamese question generation (QG). Specifically, our proposed technique concentrates on investigating both the syntactic and shallow semantic structure of each sentence. The main goal of our method is to generate questions from a single sentence. These generated questions are known as factoid questions which require short, fact-based answers. In general, syntax-based analysis is one of the most popular approaches within the QG field, but it requires linguistic expert knowledge as well as a deep understanding of syntax rules in the Vietnamese language. It is thus considered a high-cost and inefficient solution due to the requirement of significant human effort to achieve qualified syntax rules. To deal with this problem, we collected the syntax rules in Vietnamese from a Vietnamese language textbook. Moreover, we also used different natural language processing (NLP) techniques to analyze Vietnamese shallow syntax and semantics for the QG task. These techniques include: sentence segmentation, word segmentation, part of speech, chunking, dependency parsing, and named entity recognition. We used human evaluation to assess the credibility of our model, which means we manually generated questions from the corpus, and then compared them with the generated questions. The empirical evidence demonstrates that our proposed technique has significant performance, in which the generated questions are very similar to those which are created by humans.

Application of ANFIS to the design of elliptical CFST columns

Ngoc-Long Tran,Trong-Cuong Vo,Duy-Duan Nguyen,Van-Quang Nguyen,Huy-Khanh Dang,Viet-Linh Tran Techno-Press 2023 Advances in computational design Vol.8 No.2

Elliptical concrete-filled steel tubular (CFST) column is widely used in modern structures for both aesthetical appeal and structural performance benefits. The ultimate axial load is a critical factor for designing the elliptical CFST short columns. However, there are complications of geometric and material interactions, which make a difficulty in determining a simple model for predicting the ultimate axial load of elliptical CFST short columns. This study aims to propose an efficient adaptive neuro-fuzzy inference system (ANFIS) model for predicting the ultimate axial load of elliptical CFST short columns. In the proposed method, the ANFIS model is used to establish a relationship between the ultimate axial load and geometric and material properties of elliptical CFST short columns. Accordingly, a total of 188 experimental and simulation datasets of elliptical CFST short columns are used to develop the ANFIS models. The performance of the proposed ANFIS model is compared with that of existing design formulas. The results show that the proposed ANFIS model is more accurate than existing empirical and theoretical formulas. Finally, an explicit formula and a Graphical User Interface (GUI) tool are developed to apply the proposed ANFIS model for practical use.

Investigation of Extruded Endwall on Heat Transfer Characteristics of Channel with Staggering Pin-fins

Van-Hoang Tran,Thanh-Huan Nguyen,Frédéric Plourde,Khanh-Duy Cong Do,Duy-Hung Chung,Cong-Truong Dinh,Gia-Diem Pham 한국유체기계학회 2023 International journal of fluid machinery and syste Vol.16 No.2

In order to increase turbine efficiency while retaining structural integrity, modern jet engines need an effective cooling system. Pin-fin arrays play a significant role in the internal cooling system of the turbine blade. In examining the efficacy of cooling techniques using pin-fins, the other papers focus on pin-fin configurations. In contrast, the current study is a step toward optimizing cooling cascade endwalls for better maneuvering and reservation of vortices, which leads to more considerable heat transfer near the endwalls. This study examines the flow field and heat transfer of roughed endwall in the pin-fin channel, including varieties with flat endwall and extruded endwall. The heat transfer of the channel and pressure drop properties of the extruded endwall case are quantitatively assessed to contrast with those of the flat endwalls scenario for an intake Reynolds number range of 7400 to 36000. The leading and trailing surfaces of the channel are divided into five streamwise regions to understand better how well the pin-fins and endwalls transmit heat. The results show that the new endwall construction significantly increases the high heat transfer zones around the pin-fins compared to the flat endwall scenario. In the meantime, the heat transfer of the channel to the pin-fins is enhanced by the modified endwall configuration. The redesigned endwall outperformed the basic case regarding the HTEI, rising by 15.9%. It is found that the friction factor of the new design is increased due to the narrowing channel. However, due to their much higher heat transfer capacity, the HTEI of extruded endwall is up to 41.5% higher than the HTEI of the channel with flat endwalls. These results demonstrate that the heat transfer properties of pin-fins can be significantly improved by optimizing endwall design.

Methamphetamine-induced dopaminergic neurotoxicity as a model of Parkinson’s disease

Eun-Joo Shin,정지훈,Yeonggwang Hwang,Naveen Sharma,Duy-Khanh Dang,Bao-Trong Nguyen,나승열,Choon-Gon Jang,Guoying Bing,Toshitaka Nabeshima,Hyoung-Chun Kim 대한약학회 2021 Archives of Pharmacal Research Vol.44 No.7

Parkinson’s disease (PD) is a progressive neurodegenerativedisease with a high prevalence, approximately1 % in the elderly population. Numerous studies have demonstratedthat methamphetamine (MA) intoxication causedthe neurological defi cits and nigrostriatal damage seen inParkinsonian conditions, and subsequent rodent studies havefound that neurotoxic binge administration of MA reproducedPD-like features, in terms of its symptomatology andpathology. Several anti-Parkinsonian medications have beenshown to attenuate the motor impairments and dopaminergicdamage induced by MA. In addition, it has been recognized that mitochondrial dysfunction, oxidative stress, pro-apoptosis,proteasomal/autophagic impairment, and neuroinfl ammationplay important roles in inducing MA neurotoxicity. Importantly, MA neurotoxicity has been shown to share acommon mechanism of dopaminergic toxicity with that ofPD pathogenesis. This review describes the major fi ndingson the neuropathological features and underlying neurotoxicmechanisms induced by MA and compares them with Parkinsonianpathogenesis. Taken together, it is suggested thatneurotoxic binge-type administration of MA in rodents is avalid animal model for PD that may provide knowledge onthe neuropathogenesis of PD.