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.

The Effect of the Ratio of C45 Carbon to Graphene on the Si/C Composite Materials Used as Anode for Lithium-ion Batteries

Hoang Anh Nguyen,Thi Nam Pham,Le Thanh Nguyen Huynh,Tran Ha Trang Nguyen,Viet Hai Le,Nguyen Thai Hoang,Thi Thom Nguyen,Thi Thu Trang Nguyen,Dai Lam Tran,Thi Mai Thanh Dinh The Korean Electrochemical Society 2024 Journal of electrochemical science and technology Vol.15 No.2

Due to its high theoretical capacity, Silicon (Si) has shown great potential as an anode material for lithium-ion batteries (LIBs). However, the large volume change of Si during cycling leads to poor cycling stability and low Coulombic efficiency. In this study, we synthesized Si/Carbon C45:Graphene composites using a ball-milling method with a fixed Si content (20%) and investigated the influence of the C45/Gr ratio on the electrochemical performance of the composites. The results showed that carbon C45 networks can provide good conductivity, but tend to break at Si locations, resulting in poor conductivity. However, the addition of graphene helps to reconnect the broken C45 networks, improving the conductivity of the composite. Moreover, the C45 can also act as a protective coating around Si particles, reducing the volume expansion of Si during charging/discharging cycles. The Si/C45:Gr (70:10 wt%) composite exhibits improved electrochemical performance with high capacity (~1660 mAh g^-1 at 0.1 C) and cycling stability (~1370 mAh g^-1 after 100 cycles). This work highlights the effective role of carbon C45 and graphene in Si/C composites for enhancing the performance of Si-based anode materials for LIBs.

PLEKHG3 enhances polarized cell migration by activating actin filaments at the cell front

Nguyen, Trang Thi Thu,Park, Wei Sun,Park, Byung Ouk,Kim, Cha Yeon,Oh, Yohan,Kim, Jin Man,Choi, Hana,Kyung, Taeyoon,Kim, Cheol-Hee,Lee, Gabsang,Hahn, Klaus M.,Meyer, Tobias,Heo, Won Do National Academy of Sciences 2016 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.113 No.36

<P>Cells migrate by directing Ras-related C3 botulinum toxin substrate 1 (Rac1) and cell division control protein 42 (Cdc42) activities and by polymerizing actin toward the leading edge of the cell. Previous studies have proposed that this polarization process requires a local positive feedback in the leading edge involving Rac small GTPase and actin polymerization with PI3K likely playing a coordinating role. Here, we show that the pleckstrin homology and RhoGEF domain containing G3 (PLEKHG3) is a PI3K-regulated Rho guanine nucleotide exchange factor (RhoGEF) for Rac1 and Cdc42 that selectively binds to newly polymerized actin at the leading edge of migrating fibroblasts. Optogenetic inactivation of PLEKHG3 showed that PLEKHG3 is indispensable both for inducing and for maintaining cell polarity. By selectively binding to newly polymerized actin, PLEKHG3 promotes local Rac1/Cdc42 activation to induce more local actin polymerization, which in turn promotes the recruitment of more PLEKHG3 to induce and maintain cell front. Thus, autocatalytic reinforcement of PLEKHG3 localization to the leading edge of the cell provides a molecular basis for the proposed positive feedback loop that is required for cell polarization and directed migration.</P>

Raman Scattering Studies of Cu2ZnSnS4 Thin Films: Local Distribution of the Secondary Phase Cu2−xS and the Effect of KCN Etching on Cu2−xS

Trang Thi Thu Nguyen,신해영,김기영,김주리,조윌렴,윤석현,이기두,김진영 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.66 No.1

We used X-ray diffraction (XRD) and Raman scattering spectroscopy to study Cu2ZnSnS4(CZTS) thin films grown by using an electroplating method. We compared the Raman spectraof the CZTS thin films before and after potassium cyanide (KCN) etching. We observed a phononmode of the secondary phase Cu2−xS both from Cu-rich and Cu-poor CZTS samples before theKCN etching. We found that the intensity of the Cu2−xS-related vibration mode depended on theexcitation wavelength, from which we could estimate the stoichiometry of the Cu2−xS as x = 1. Interestingly, the Cu2−xS phonon is completely removed after the KCN etching. We could also getinformation regarding the local distribution of the secondary phase on the surfaces of the CZTSthin films by using micro-Raman scattering spectroscopy.

Application of Polyethylene/Modified Fly Ash/Ultra Flow Agent Composites in Vietnam

Nguyen Thuy Chinh,Nguyen Thi Thu Trang,Tran Thi Mai,Nguyen Vu Giang,Tran Huu Trung,Mai Duc Huynh,Thai Hoang 한국고분자학회 2019 한국고분자학회 학술대회 연구논문 초록집 Vol.44 No.1

Detecting user status from smartphone sensor data

Thu-Trang Nguyen,Thi-Hau Nguyen,Ha-Nam Nguyen,Duc-Nhan Nguyen,GyooSeok Choi 국제문화기술진흥원 2016 International Journal of Advanced Culture Technolo Vol.4 No.1

Due to the high increment in usage and built-in advanced technology of smartphones, human activity recognition relying on smartphone sensor data has become a focused research area. In order to reduce noise of collected data, most of previous studies assume that smartphones are fixed at certain positions. This strategy is impractical for real life applications. To overcome this issue, we here investigate a framework that allows detecting the status of a traveller as idle or moving regardless the position and the direction of smartphones. The application of our work is to estimate the total energy consumption of a traveller during a trip. A number of experiments have been carried out to show the effectiveness of our framework when travellers are not only walking but also using primitive vehicles like motorbikes.

Spatial-temporal distribution of hexabromocyclododecanes (HBCDDs) in multiple environmental matrices from Masan Bay, Korea

Trang Thi Thu Nguyen,Hyun-Kyung Lee,Chang-Hwa Lee,Hyo-Bang Moon 환경독성보건학회 2022 한국독성학회 심포지움 및 학술발표회 Vol.2022 No.5

Compounds from the Aerial Parts of Aceriphyllum rossii and Their Cytotoxic Activity

Thi Thu Trang Tran,민병선,Thi Yen Nguyen,Manh Hung Tran,원권연,우미희 한국생약학회 2014 Natural Product Sciences Vol.20 No.3

The purification of the MeOH extracts from the aerial parts of Aceriphyllum rossii Engler (Saxifragaceae) using column chromatography furnished fourteen compounds (1 - 14). The chemical structures of the isolated compounds were determined using mainly nuclear magnetic resonance spectra and mass spectrometry. All the isolated compounds were tested for their cytotoxic activity against LH-60, MCF-7 and HeLa cancer cells in vitro using a MTT assay method. Compounds possessing an olean-triterpenoid skeleton entirely exhibit dose dependent cytotoxic activity. These findings partially confirmed the anticancer effect of this medicinal plant, suggesting a further study on the anticancer potential of the triterpenoid structure in compounds from this plant.

Raman scattering study of phase transition and vibration modes in MA cation of CH3NH3PbBr3 single crystals

Trang Thi Thu Nguyen,Yejin Kim,Hye Ri Jung,William Jo,Won Seok Woo,Chang Won Ahn,Shinuk Cho,Ill Won Kim,Seokhyun Yoon 한국진공학회 2019 한국진공학회 학술발표회초록집 Vol.2019 No.2

Deep eutectic solvent-assisted synthesis of gold nanoflowers supported on glassy carbon electrode for DNA sensor application

Trang Nguyen Thi Kieu,Phuong Thao Dao Vu,Nguyet Nguyen Thi,Dien Nguyen Dac,Van Hoang Nhu,Van Thu Vu,Tran Manh Trung,Pham Hung Vuong,Tam Phuong Dinh 한국물리학회 2024 Current Applied Physics Vol.63 No.-

Gold nanoflowers (AuNF) were synthesized on a glassy carbon electrode via a one-step, eco-friendly protocol in deep eutectic solvent (DES) of choline choloride and urea, called reline, for label-free detection of DNA hybridization. DES is eco-friendly, low-cost, biocompatible, and nontoxic, and it can be used as an electrolyte to synthesize nanomaterials by using the electrochemical method. In this protocol, highly branched and stable AuNFs were obtained without using any surfactants for DNA sensor application. The electrochemical performance of the AuNF-modified electrode was studied by cyclic voltammetry and electrochemical impedance spectroscopy. Under optimal conditions, the AuNF-based DNA biosensor exhibited a sensitivity of 294.9 Ω nM−1cm−2 and 218 μA nM−1cm−2 and a limit of detection (LOD) of 10−9 M. The remarkable sensitivity and low LOD could be attributed to the good conductivity of AuNFs for accelerating electron transfer, resulting in obvious signal amplification. The DNA biosensor showed good reproducibility (RSD <3.65 %) and acceptable stability and selectivity. Its excellent performance in DNA detection suggested that the proposed electrochemical DNA sensor has great application potential in clinical diagnosis.