39 results on '"Tien-Thanh Nguyen"'
Search Results
2. The Wannier-Mott Exciton, Bound Exciton, and Optical Phonon Replicas of Single-Crystal GaSe
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Long V. Le, Tran Thi Thu Huong, Tien-Thanh Nguyen, Xuan Au Nguyen, Thi Huong Nguyen, Sunglae Cho, Young Dong Kim, and Tae Jung Kim
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GaSe thin slab ,free exciton ,bound exciton ,optical phonon replicas ,Crystallography ,QD901-999 - Abstract
We report the absorption and photoluminescence spectra of GaSe single crystals in the near-edge region. The temperatures explored the range from 17 to 300 K. Specifically, at a temperature of 17 K, the photoluminescence spectrum reveals an interesting phenomenon: the Wannier-Mott exciton separates into two states. These states are a triplet state with an energy of 2.103 eV and a singlet state with an energy of 2.109 eV. The energy difference between these two states is 6 meV. Furthermore, the bound exciton (BX) can be localized at an energy of 2.093 eV. It is worth noting that its phonon replicas (BX-nLO) can be clearly distinguished up to the fourth order. Interestingly, the energy gaps between these replicas exhibit a consistent spacing of 7 ± 0.5 meV. This intriguing finding suggests a high-quality crystalline structure as well as a strong coupling between the phonon and BX-nLO. Additionally, at low temperatures, both the ground state (n = 1) at 2.11 eV and the excited state (n = 2) at 2.127 eV of free excitons can be observed.
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- 2024
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3. A Systematic Study of the Temperature Dependence of the Dielectric Function of GaSe Uniaxial Crystals from 27 to 300 K
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Long V. Le, Tien-Thanh Nguyen, Xuan Au Nguyen, Do Duc Cuong, Thi Huong Nguyen, Van Quang Nguyen, Sunglae Cho, Young Dong Kim, and Tae Jung Kim
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uniaxual crystal GaSe ,spectroscopic ellipsometry ,dielectric function ,exciton ,first-principles calculations ,Chemistry ,QD1-999 - Abstract
We report the temperature dependences of the dielectric function ε = ε1 + iε2 and critical point (CP) energies of the uniaxial crystal GaSe in the spectral energy region from 0.74 to 6.42 eV and at temperatures from 27 to 300 K using spectroscopic ellipsometry. The fundamental bandgap and strong exciton effect near 2.1 eV are detected only in the c-direction, which is perpendicular to the cleavage plane of the crystal. The temperature dependences of the CP energies were determined by fitting the data to the phenomenological expression that incorporates the Bose–Einstein statistical factor and the temperature coefficient to describe the electron–phonon interaction. To determine the origin of this anisotropy, we perform first-principles calculations using the mBJ method for bandgap correction. The results clearly demonstrate that the anisotropic dielectric characteristics can be directly attributed to the inherent anisotropy of p orbitals. More specifically, this prominent excitonic feature and fundamental bandgap are derived from the band-to-band transition between s and pz orbitals at the Γ-point.
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- 2024
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4. Hand Activity Recognition From Automatic Estimated Egocentric Skeletons Combining Slow Fast and Graphical Neural Networks
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Viet-Duc Le, Van-Nam Hoang, Tien-Thanh Nguyen, Van-Hung Le, Thanh-Hai Tran, Hai Vu, and Thi-Lan Le
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2D/3D hand pose estimation ,egocentric vision ,GCN ,DDNet ,hand action recognition ,Information technology ,T58.5-58.64 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
In this paper, we present an unified framework for understanding hand action from the first-person video. The proposed framework composes two main components. The first component estimates three-dimensional (3D) hand joints from RGB images. Two network structures derived from the baseline HopeNet network are proposed: convolutional neural networks (CNNs) which are traditional multi-layer CNN and CNN combining with GraphCNN to perform 3D hand pose estimation, without the use of GraphUNet as in baseline HopeNet method. The second component of the framework recognizes hand action from skeleton stream. We first deploy two recent advanced neuronal networks that are PA-ResGCN and Double-feature Double-motion (DDNet). To focus more on the hand pose changes, we improve DDNet with two normalization strategies of the hand joints. Finally, we fuse PA-ResGCN with our improved DDNet to still boost the recognition performance. We evaluate our proposed methods on First-Person Hand Action Benchmark dataset. Experiments show that our model for 3D hand joints estimation achieves the best precision (36.6 mm). Our hand joint normalization strategies improve the original DDNet from 0.71% to 4.05% of accuracy with the ground-truth hand pose while the improvement is significantly larger (from 2.96% to 10.98%) with the estimated hand pose. The late fusion schemes outperform different state-of-the-art methods for the hand action recognition with the highest accuracy of 86.67%. These experimental results show potential and extendable possibilities for developing practical first-person vision applications.
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- 2023
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5. A robust and efficient method for skeleton‐based human action recognition and its application for cross‐dataset evaluation
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Tien‐Thanh Nguyen, Dinh‐Tan Pham, Hai Vu, and Thi‐Lan Le
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Computer software ,QA76.75-76.765 - Abstract
Abstract Skeleton‐based human action recognition has emerged recently thanks to its compactness and robustness to appearance variations. Although impressive results have been obtained in recent years, the performance of skeleton‐based action recognition methods has to be improved to be deployed in real‐time applications. Recently, a lightweight network structure named Double‐feature Double‐motion Network (DD‐Net) has been proposed for the skeleton‐based human action recognition. With high speed, the DD‐Net achieves state‐of‐the‐art performance on hand and body actions. The DD‐Net could not distinguish actions if they have a weak connection with the global trajectories. However, the DD‐Net is suitable for human action recognition where actions strongly correlate to the global trajectories. In this paper, the authors propose TD‐Net, an improved version of the DD‐Net in which a new branch is added. The new branch takes the normalised coordinates of joints (NCJ) to enrich the spatial information. On five datasets for skeleton‐based human activity recognition that are MSR‐Action3D, CMDFall, JHMDB, FPHAB, and NTU RGB + D, the TD‐Net consistently obtains superior performance compared with the baseline model DD‐Net. The proposed method outperforms different state‐of‐the‐art methods, including both hand‐designed and deep learning‐based methods on four datasets (MSR‐Action3D, CMDFall, JHMDB, and FPHAB). Furthermore, the generalisation of the proposed method is confirmed through cross‐dataset evaluation. To illustrate the potential use of the model for real‐time human action recognition, the authors have deployed an application on an edge device. The experimental result shows that the application can process up to 40 fps for pose estimation using MediaPipe. It takes only 0.04 ms to recognise an action from skeleton sequences.
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- 2022
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6. In situ synthesis of highly effective nickel nanocatalyst for methane bireforming
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Nguyen Tri, Nguyen Phung Anh, Tran Duc Huy, Do Ba Long, Ha Cam Anh, Phan Hong Phuong, Nguyen Thi Thuy Van, Tien-Thanh Nguyen, and Luu Cam Loc
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In situ synthesis ,CeNiO3 perovskite ,Nickel nanocatalyst ,Methane bireforming ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
This work offered insights into the characteristics and performance of nickel nanocatalyst in situ synthesized through CeNiO3 perovskite for the bireforming of methane (BRM). Effects of calcination conditions on the characteristics of CeNiO3 structure and on the reduction regime of the as-prepared perovskite on the physicochemical properties and performance of nickel catalyst in BRM were assessed. The formation of high-crystallinity CeNiO3 at temperatures above 700 °C was confirmed. The synthesized CeNiO3 existed in the form of spherical particles 20–40 nm in size and uniformly distributed. Among the samples, one calcined at 700 °C for 2 h (C-700-2.0) had the smallest and the most uniform particle and the highest reducibility. This sample was found to be the optimum precursor for the in situ synthesis of a highly effective nano-Ni catalyst for BRM. The reduction mode significantly affected the catalytic performance of the C-700-2.0 precursor. The sample reduced at 750 °C for 1.5 h (R-750-1.5) possessed the optimum activity, with conversions of CH4 and CO2 reaching equilibrium (98% and 84%, respectively) and an ideal H2/CO ratio of 2 at the reaction temperature of 700 °C.
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- 2023
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7. Green-synthesized silver nanoparticles decorated on ceria nanorods for room-temperature p-nitrophenol hydrogenation
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Trung Dang-Bao, Nguyen Hoang Bao, Nguyen Phung Anh, Phan Hong Phuong, Tien-Thanh Nguyen, and Nguyen Tri
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Silver ,ceria ,nanoparticles ,p-nitrophenol ,hydrogenation ,Science ,Chemistry ,QD1-999 - Abstract
In this study, silver nanoparticles (AgNPs) loaded on pre-formed CeO2 nanorods (Ag-Ce) were synthesized using Jasminum subtriplinerve Blume leaf extract as a reducing agent. The mesoporous structure of CeO2 was confirmed by the N2 adsorption/desorption study, indicating type ІV isotherms with an H3-type hysteresis loop. The high specific surface area of the Ag-Ce samples was discovered in the range of 74–80 m2/g with an average pore diameter of 23.2–23.4 Å, and a pore volume of 0.091–0.093 cm3/g (pure CeO2 of 72 m2/g, 23 Å, and 0.098 cm3/g, respectively). Silver nanoparticles with spherical shapes (5–10 nm in diameter) were well dispersed on the surface of CeO2 nanorods (100–200 nm in length and 20–30 nm in diameter), as shown by X-ray diffraction (XRD), Energy-dispersive X-ray (EDX) and high-resolution transmission electron microscopy (HR-TEM). Their catalytic reactivity was investigated in the hydrogenation of p-nitrophenol (p-NP) toward p-aminophenol (p-AP) using NaBH4 at room temperature, exhibiting better reactivity of the Ag-Ce samples than pure CeO2 nanorods. The 0.2Ag-Ce sample (0.2 wt.% Ag) showed the complete conversion of p-NP toward p-AP after 3 min using 0.2 g/L catalysts.
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- 2022
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8. The ability of silver-biochar green-synthesized from Citrus maxima peel to adsorb pollutant organic compounds and antibacterial activity
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Ngoc Dai Nghia Tran, Thu Ha Bui, Anh Phung Nguyen, Tien-Thanh Nguyen, Van Minh Nguyen, Nhat Linh Duong, and Tri Nguyen
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citrus maxima peel ,silver-biochar ,green synthesis ,antibacterial ,adsorption ,Science ,Chemistry ,QD1-999 - Abstract
Citrus maxima peel (CMP) was utilized for the green synthesis of multifunctional silver-biochar material (Ag-CMPB). An alternative, cost-effective and eco-friendly technique was performed using the CMP extract as a reducing agent for the biosynthesis of Ag-CMPB material, in which biochar is prepared from CMP residue. Ag-CMPB nanomaterials were characterized by various physico-chemical methods such as XRD, HRTEM, BET, FT-IR, EDX, and PZC. The results revealed the formation of the face-centered cubic structure of Ag with the particle size in a range of 3 − 10 nm and the stacking structure of layers of biochar. Flavonoids and phenolic acids in CMP extract as a reducing agent of Ag-CMPB material. The specific surface area of Ag-CMPB was determined to be 79.2 m2/g with a pore diameter of 22.4 Å. Ag-CMPB showed high efficiency in the short time in removing organic compounds. The adsorption efficiency was recognized in the following sequence for POPs adsorption: Methyl blue > Rhodamine B > Methyl orange, with the adsorption capacities of 95.5, 69.3, and 51.5 mg/g, respectively. The antibacterial activity of Ag-CMPB was evaluated on five bacteria against B. cereus, E. coli, P. aeruginosa, S. aureus, and Salmonella by the zone of inhibition and MIC value.
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- 2022
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9. Gis And Remote Sensing: A Review Of Applications To The Study Of The Covid-19 Pandemic
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Quoc-lap Kieu, Tien-thanh Nguyen, and Anh-huy Hoang
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remote sensing ,applications ,covid-19 ,viral infection ,impacts ,environment ,Geography (General) ,G1-922 - Abstract
The spread of the 2019 novel coronavirus disease (COVID-19) has engulfed the world with a rapid, unexpected, and far-reaching global crisis. In the study of COVID-19, Geographic Information Systems (GIS) and Remote Sensing (RS) have played an important role in many aspects, especially in the fight against COVID-19. This review summarises 102 scientific papers on applications of GIS and RS on studies of the COVID-19 pandemic. In this study, two themes of GIS and RS-related applications are grouped into the six categories of studies of the COVID-19 including spatio-temporal changes, WebGISbased mapping, the correlation between the COVID-19 and natural, socio-economic factors, and the environmental impacts. The findings of this study provide insight into how to apply new techniques (GIS and RS) to better understand, better manage the evolution of the COVID-19 pandemic and effectively assess its impacts.
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- 2021
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10. Spatial Clustering Analysis of the COVID-19 Pandemic: A Case Study of the Fourth Wave in Vietnam
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Danh-tuyen Vu, Tien-thanh Nguyen, and Anh-huy Hoang
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spatial clustering ,spatial auto-correlation ,covid-19 pandemic ,vietnam’s fourth wave ,Geography (General) ,G1-922 - Abstract
An outbreak of the 2019 Novel Coronavirus Disease (COVID-19) in China caused by the emergence of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARSCoV2) spreads rapidly across the world and has negatively affected almost all countries including such the developing country as Vietnam. This study aimed to analyze the spatial clustering of the COVID-19 pandemic using spatial auto-correlation analysis. The spatial clustering including spatial clusters (high-high and low-low), spatial outliers (low-high and high-low), and hotspots of the COVID-19 pandemic were explored using the local Moran’s I and Getis-Ord’s G* i statistics. The local Moran’s I and Moran scatterplot were first employed to identify spatial clusters and spatial outliers of COVID-19. The Getis-Ord’s G* i statistic was then used to detect hotspots of COVID-19. The method has been illustrated using a dataset of 86,277 locally transmitted cases confirmed in two phases of the fourth COVID-19 wave in Vietnam. It was shown that significant low-high spatial outliers and hotspots of COVID-19 were first detected in the NorthEastern region in the first phase, whereas, high-high clusters and low-high outliers and hotspots were then detected in the Southern region of Vietnam. The present findings confirm the effectiveness of spatial auto-correlation in the fight against the COVID-19 pandemic, especially in the study of spatial clustering of COVID-19. The insights gained from this study may be of assistance to mitigate the health, economic, environmental, and social impacts of the COVID-19 pandemic.
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- 2021
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11. Cellulose from the banana stem: optimization of extraction by response surface methodology (RSM) and charaterization
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Nguyen Thi Thuy Van, Pag-asa Gaspillo, Ho Gia Thien Thanh, Nguyen Huynh Thao Nhi, Huynh Nhat Long, Nguyen Tri, Nguyen Thi Truc Van, Tien-Thanh Nguyen, and Huynh Ky Phuong Ha
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Banana ,Cellulose ,Modeling and optimization ,Response surface methodology ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Cellulose was extracted from the banana stem by chemical method and the factors affecting the extraction process such as concentration of NaOH and H2O2, as well as the assisted microwave time were investigated. Design-Expert software with Response Surface Methodology was used in the modeling and optimization of the cellulose extraction process. The results of XRD, FT-IR, SEM were also used to determine the physicochemical properties of cellulose obtained from the banana stem. The results of the modeling and optimization process of cellulose extraction showed the efficiency of the process and the high applicability of cellulose from the banana stem to create valuable industrial products.
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- 2022
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12. Surface functionalization of nylon 66 membrane using para-phenylenediamine and carboxylic functionalized multi-walled carbon nanotubes for removal of calcium ions from aqueous solution
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Duc-Binh Nguyen, Nguyen Thi Hong Van, Tien-Thanh Nguyen, Vinh-Dat Vuong, Dat Quoc Lai, Mai Thanh Phong, and Thang Van Le
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nylon 66 membrane ,nylon 66/ppd/mwcnts ,surface functionalization ,silica gel catalyzed amidation ,ultrasound assisted amidation ,calcium ion rejection ,carboxylic functionalized multi-walled carbon nanotubes (mwcnt-cooh) ,bundled mwcnts bridge ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Polymers and polymer manufacture ,TP1080-1185 - Abstract
Nylon 66, which is an important membrane class used in manufacturing of chitin and chitosan, have a number of features that can be improved by surface functionalizations into a novel composite structure with support of ultrasound and silica gel (SiG) catalyst in a doubled amidation reaction. Firstly, nylon 66/para-phenylenediamine thin film composite (NP-TFC) is prepared from commercial nylon 66 membrane in an ultrasound assisted hydrolysis-amidation reaction. Secondly, carboxylic functionalized multi-walled carbon nanotubes (MWCNT-COOH) are grafted on the NP fiber in an ultrasound assisted/SiG-catalyzed amidation reaction, where para-phenylenediamine (pPD) role is cross-linking. As an excellent result confirmed by either Fourier transform infrared (FTIR), Raman spectrometry or scanning electron microscopic (SEM), bundled MWCNTs bridges are easily built in SiG-catalyzed ethanol media to connect nylon 66 fibers at distances of 0.3–1 μm. The vacuum filtration test confirmed that as-prepared nylon 66/pPD/MWCNTs structure has superior Ca2+ rejection efficiency to that of original nylon 66.
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- 2021
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13. Adaptive Fuzzy Sliding Control for Balancing Pendubot
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Van-Dong-Hai Nguyen, Xuan-Dung Huynh, Pham-Phu Tran, Ba-Huy Nguyen, Tien-Thanh Nguyen, Tran-Minh-Nguyet Nguyen, and Thien-Van Nguyen
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sliding control ,adaptive fuzzy sliding control ,simo system ,lyapunov ,pendubot ,Technology (General) ,T1-995 ,Industrial engineering. Management engineering ,T55.4-60.8 ,Management information systems ,T58.6-58.62 - Abstract
In many cases of sliding control, the exact nonlinear functions of dynamic equations are difficult to be obtained. Because of this reason, the uncertainty of nonlinear functions of system can cause bad response under sliding control. In this paper, we suggest an adaptive fuzzy sliding control method which can balance a SIMO system. This method still guarantees the stability of system by Lyapunov criteria. Otherwise, the problem of uncertainty of nonlinear system is solved. The object chosen in this paper is pendubot - a popular model in control laboratory. The success of this method is proved by simulation results.
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- 2020
14. Circulating-infiltrating preparation of hydrophilic nylon 6 membrane to hydrophobic MWCNT@nylon composite membrane
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Mai Thanh Phong, Vinh-Dat Vuong, Nguyen Tan Tai, Muhammad Firdaus Mohd Nazeri, Tien-Thanh Nguyen, Pham Tan Thi, and Thang Van Le
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circulating-infiltrating reaction ,amino-enriched nylon ,multi-walled carbon nanotubes grafted nylon ,hydrophobic membrane ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
The ion adsorption capacity has been added to the nylon 6 microfiltration (MF) membrane by grafting the fibers in its structure with carboxylated multi-walled carbon nanotubes (MWCNT-COOH). Through a direct three-step functionalization reaction with hexamethylenediamine (HMDA) and MWCNT-COOH, the multi-walled carbon nanotubes grafted nylon (MWCNT@nylon) fibers are made up of original nylon 6 and intermediate amino-enriched (nylon-NH _2 ) membranes. Chemical structure analysis shows that HMDA and MWCNTs were grafted to the nylon 6 fiber side wall, without causing damage to either the nylon 6 backbone or the pore size of the original membrane. The SEM images confirm this and further confirm that the plexus of MWCNT-COOH has a pore size of approximately 50 nm, covering the nylon 6 fibers. The sidewall of nylon-NH _2 and MWCNT@nylon fibers contains hydrophilic groups (amino and carboxylic), allowing the as-prepared membranes to reduce the wetting angle from about 70.3° to about 108.1°. This special structure opens new possibilities for polyamide membranes as well as mass production by the proposed simple method.
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- 2023
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15. Speciation Analysis of Arsenic Compounds by High-Performance Liquid Chromatography in Combination with Inductively Coupled Plasma Dynamic Reaction Cell Quadrupole Mass Spectrometry: Application for Vietnamese Rice Samples
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Hai Anh Vu, Manh Ha Nguyen, Hong-An Vu-Thi, Quan Do-Hong, Xuan Hoang Dang, Thi Ngoc Bich Nguyen, Hong Quan Trinh, Thuy Ly Bich, Tien-Thanh Nguyen, Dung Le-Van, Minh Binh Tu, and Dinh Binh Chu
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Analytical chemistry ,QD71-142 - Abstract
In this work, high-performance liquid chromatography in combination with inductively coupled plasma dynamic reaction cell quadrupole mass spectrometry was introduced and optimized for speciation analysis of five major arsenic species including arsenobetain (AsB), arsenite (As(III)), monomethylarsonic (MMA), dimethylarsenonic acid (DMA), and arsenate (As(V)) in rice samples. Five arsenic compounds were separated on a Hamilton PRP X100 strong anion-exchange column employed with the mobile phase that is compatible with mass spectrometry, containing ammonium carbonate, methanol, and disodium ethylenediaminetetraacetic acid. Arsenic compounds were detected online by inductively coupled plasma dynamic reaction cell quadrupole mass spectrometry utilizing oxygen as the reaction gas at a flow rate of 0.7 mL·min−1. Five selected arsenic species were baseline separated at the optimum experimental conditions. The excellent LOD and LOQ values of the developed method were achieved in the range of 0.5 to 2.9 μg·kg−1 and 1.7 to 9.6 μg·kg−1 for all species of arsenic, respectively. The ionization effect in plasma during chromatographic gradient elution was systematically investigated by using postcolumn injector. Arsenic compounds in rice samples were extracted by diluted nitric acid at elevated temperature. The extraction efficiency and the interconversion of target compounds during sample preparation were also assessed. The full validation of the developed method was performed by using certified reference material, BRC 211, from European Institute of Reference and Standard for speciation analysis. The recovery of all selected arsenic species was in the range of 70 to 135.5%. The validated method was also applied to analyze rice samples collected from some contaminated rice fields. The results showed that As(III), DMA, and As(V) were found in all rice samples. Average concentration (range) of inorganic arsenic and DMA in all rice samples were 130.3 (65.5–228.1) and 32 (8.2–133.01) μg·kg−1, respectively. However, total concentration of inorganic arsenic in most of investigated rice samples was below the maximum residual level according to US-FDA and European Union standards.
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- 2019
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16. Microorganisms, the Ultimate Tool for Clean Label Foods?
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Giorgia Perpetuini, Pumnat Chuenchomrat, Valentin Pereyron, Maxime Haure, Da Lorn, Le-Ha Quan, Phu-Ha Ho, Tien-Thanh Nguyen, Thi-Yen Do, Quyet-Tien Phi, Thi Kim Chi Nguyen, Hélène Licandro, Son Chu-Ky, Rosanna Tofalo, Warissara Kasikonsunthonchai, Saowalak Adunphatcharaphon, Awanwee Petchkongkaew, and Yves Waché
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clean-label ,technology additive ,sensorial additive ,anti-staling ,bioremediation ,biosurfactants ,Engineering machinery, tools, and implements ,TA213-215 ,Technological innovations. Automation ,HD45-45.2 - Abstract
Clean label is an important trend in the food industry. It aims at washing foods of chemicals perceived as unhealthy by consumers. Microorganisms are present in many foods (usually fermented), they exhibit a diversity of metabolism and some can bring probiotic properties. They are usually well considered by consumers and, with progresses in the knowledge of their physiology and behavior, they can become very precise tools to produce or degrade specific compounds. They are thus an interesting means to obtain clean label foods. In this review, we propose to discuss some current research to use microorganisms to produce clean label foods with examples improving sensorial, textural, health and nutritional properties.
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- 2021
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17. Immobilization of β-Galactosidases on the Lactobacillus Cell Surface Using the Peptidoglycan-Binding Motif LysM
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Mai-Lan Pham, Anh-Minh Tran, Suwapat Kittibunchakul, Tien-Thanh Nguyen, Geir Mathiesen, and Thu-Ha Nguyen
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Lactobacillus ,β-galactosidase ,immobilization ,cell surface display ,LysM domains ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Lysin motif (LysM) domains are found in many bacterial peptidoglycan hydrolases. They can bind non-covalently to peptidoglycan and have been employed to display heterologous proteins on the bacterial cell surface. In this study, we aimed to use a single LysM domain derived from a putative extracellular transglycosylase Lp_3014 of Lactobacillus plantarum WCFS1 to display two different lactobacillal β-galactosidases, the heterodimeric LacLM-type from Lactobacillus reuteri and the homodimeric LacZ-type from Lactobacillus delbrueckii subsp. bulgaricus, on the cell surface of different Lactobacillus spp. The β-galactosidases were fused with the LysM domain and the fusion proteins, LysM-LacLMLreu and LysM-LacZLbul, were successfully expressed in Escherichia coli and subsequently displayed on the cell surface of L. plantarum WCFS1. β-Galactosidase activities obtained for L. plantarum displaying cells were 179 and 1153 U per g dry cell weight, or the amounts of active surface-anchored β-galactosidase were 0.99 and 4.61 mg per g dry cell weight for LysM-LacLMLreu and LysM-LacZLbul, respectively. LysM-LacZLbul was also displayed on the cell surface of other Lactobacillus spp. including L. delbrueckii subsp. bulgaricus, L. casei and L. helveticus, however L. plantarum is shown to be the best among Lactobacillus spp. tested for surface display of fusion LysM-LacZLbul, both with respect to the immobilization yield as well as the amount of active surface-anchored enzyme. The immobilized fusion LysM-β-galactosidases are catalytically efficient and can be reused for several repeated rounds of lactose conversion. This approach, with the β-galactosidases being displayed on the cell surface of non-genetically modified food-grade organisms, shows potential for applications of these immobilized enzymes in the synthesis of prebiotic galacto-oligosaccharides.
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- 2019
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18. Fundamental understanding of in-situ transesterification of microalgae biomass to biodiesel: A critical review
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Tien Thanh, Nguyen, Mostapha, Marhaini, Lam, Man Kee, Ishak, Syukriyah, Kanna Dasan, Yaleeni, Lim, Jun Wei, Tan, Inn Shi, Lau, Sie Yon, Chin, Bridgid Lai Fui, and Hadibarata, Tony
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- 2022
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19. Straightforward electrochemical synthesis of a Co3O4 nanopetal/ZnO nanoplate p-n junction for photoelectrochemical water splitting.
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Khanh Quang Nguyen, Hoang Thai Nguyen, Thach Khac Bui, Tien-Thanh Nguyen, and Viet Van Pham
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- 2024
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20. DELINEATION OF COAL FIRE RISK AREAS FROM LANDSAT-8 TIRS DATA: A CASE STUDY OF NA DUONG COALFIELD (NORTH-EAST OF VIETNAM).
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Danh-tuyen VU, Tien-thanh NGUYEN, Anh-huy HOANG, and Thi-thu-huong PHAM
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THERMAL coal , *COAL , *LAND surface temperature , *COALFIELDS - Abstract
Coal fires are a persistent threat to major coal-producing countries in the world. Thus, it is very important to delineate the potential risks of coal fires. This study presents a method for the delineation of coal fire risk areas from Landsat-8 TIRS data. Land surface temperatures (LSTs) were first retrieved from the Landsat-8 TIRS images. The degree of spatial autocorrelation among these LSTs was then identified using local Moran's I statistic. Thermal-related anomalies for the delineation of coal fire risk areas were identified by setting the MEAN+2*SDEV (SDEV is the standard deviation), MEAN+3*SDEV, and MEAN+4*SDEV formulas as thresholds on the local Moran's I statistic. These coal fire risk areas were finally validated using known coal fire sites and cross-validated by comparing them with those obtained from hot spot analysis. A case study of the Na Duong coal field (northern Vietnam) has shown that coal fire risks at moderate and high levels were mainly detected in the center of the coal field. The higher values of local Moran's I statistic, the higher levels of coal fire risks. These coal fire risks were mainly concentrated around known coal fire sites. These results reveal that Landsat-8 TIRS data can effectively delineate coal fire risk areas. [ABSTRACT FROM AUTHOR]
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- 2023
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21. Microorganisms, the Ultimate Tool for Clean Label Foods ?
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Thi Kim Chi Nguyen, Saowalak Adunphatcharaphon, Le-Ha Quan, Hélène Licandro, Rosanna Tofalo, Quyet-Tien Phi, Giorgia Perpetuini, Valentin Pereyron, Warissara Kasikonsunthonchai, Son Chu-Ky, Tien-Thanh Nguyen, Yves Waché, Da Lorn, Thi-Yen Do, Phu-Ha Ho, Awanwee Petchkongkaew, Pumnat Chuenchomrat, Maxime Haure, Faculty of BioScience and Technology for Food, Agriculture and Environment, University of Teramo (UT), Thammasat University (TU), International Joint Laboratory Tropical Bioresources & Biotechnology [Hanoi] (SBFT), Hanoi University of Science and Technology (HUST), Food Biotech&Innovation (FBI), Procédés Alimentaires et Microbiologiques [Dijon] (PAM), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Institute of Technology of Cambodia [Cambodge] (KHM), School of Biotechnology and Food Technology, Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi 10000, Vietnam, Institute for Global Food Security [Belfast], Queen's University [Belfast] (QUB), and Research Network: Tropical Fermentation Network
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Technological innovations. Automation ,0106 biological sciences ,0301 basic medicine ,Food industry ,Sensorial additive ,Microorganism ,Beneficial microorganisms ,anti-staling ,clean-label ,01 natural sciences ,law.invention ,Beneficial microorganism ,biosurfactants ,03 medical and health sciences ,Probiotic ,Clean-label ,bioremediation ,law ,010608 biotechnology ,Anti-staling ,Antibiofilm ,Antinutrition ,Bio-preservation ,Bioremediation ,Biosurfactants ,Technology additive ,sensorial additive ,2. Zero hunger ,bio-preservation ,beneficial microorganism ,antibiofilm ,business.industry ,HD45-45.2 ,digestive, oral, and skin physiology ,General Engineering ,TA213-215 ,antinutrition ,Biotechnology ,Engineering machinery, tools, and implements ,030104 developmental biology ,[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,technology additive ,business ,[SDV.AEN]Life Sciences [q-bio]/Food and Nutrition - Abstract
International audience; Clean label is an important trend in the food industry. It aims at washing foods of chemicals perceived as unhealthy by consumers. Microorganisms are present in many foods (usually fermented), they exhibit a diversity of metabolism and some can bring probiotic properties. They are usually well considered by consumers and, with progresses in the knowledge of their physiology and behavior, they can become very precise tools to produce or degrade specific compounds. They are thus an interesting means to obtain clean label foods. In this review, we propose to discuss some current research to use microorganisms to produce clean label foods with examples improving sensorial, textural, health and nutritional properties.
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- 2021
22. High-Level Reliability Evaluation of Reconfiguration-Based Fault Tolerance Techniques
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Mathieu Thevenin, Gwenolé Corre, Tien Thanh Nguyen, Olivier Pasquier, Sébastien Pillement, Anthony Mouraud, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), CEA Tech en régions (CEA-TECH-Reg), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Charlier, Sandrine, Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Rennes 1 (UR1)
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010308 nuclear & particles physics ,Computer science ,Control reconfiguration ,Fault tolerance ,02 engineering and technology ,01 natural sciences ,[SPI.TRON] Engineering Sciences [physics]/Electronics ,020202 computer hardware & architecture ,Reliability engineering ,[SPI.TRON]Engineering Sciences [physics]/Electronics ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Redundancy (engineering) ,Field-programmable gate array - Abstract
Field Programmable Gate Arrays (FPGAs) offer very efficient fault-tolerance strategies based on partial reconfiguration. These strategies use dedicated spare resources at different levels to replace faulty elements. A method to determine if the targeted level of reliability can be obtained is then required. In this paper, we generalize the reliability estimation formulas for the state-of-the-art fault tolerance techniques based on partial reconfiguration. We use those formulas to estimate the bounds of the different techniques in terms of reliability level and bitstream overhead. This work makes possible to evaluate early in the design-flow the achievable mission time for a given number of faults per time unit. Thanks to its generality, our approach can be derived for future new partial reconfiguration approaches.
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- 2018
23. Influence of Thermal Annealing Media on Optical and Electrical Properties of FTO, ITO and TiO2 Films.
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Tien Thanh Nguyen, Khac An Dao, Thi Thuy Nguyen, Chung Dong Nguyen, Si Hieu Nguyen, and Thi Mai Huong Nguyen
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TITANIUM dioxide films ,ELECTRIC properties of materials ,N-type semiconductors ,METALLIC oxides ,CRYSTAL lattices - Abstract
Metal oxides, in many cases, exhibit n-type semiconductors due to the existence of oxygen vacancies in the lattice. Therefore, the interactions of oxygen being in medium with oxygen vacancies during the annealing process can change concentrations of defects that will cause variations in optical and electric properties of such materials. However, research on such interactions for commercial FTO, ITO, and TiO2 products has been limited. This paper summarizes the results of some experiments conducted to determine the influence of thermal annealing media on the optical, electrical properties of thin films of these products. The thermal media considered are air medium, 101 torr low vacuum condition, and Argon gas environments, and the annealing condition is set at 450°C for 20 minutes. It is found that while FTO films change for the better after annealing, ITO films trend towards worse, and TiO
2 films have the most photoconversion efficiency (Isc = 0.27 mA, η = 0.37%) under the moderate oxygen concentration environment. [ABSTRACT FROM AUTHOR]- Published
- 2020
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24. Model-driven reliability evaluation for MPSoC design
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Olivier Pasquier, Anthony Mouraud, Tien Thanh Nguyen, Sébastien Pillement, Mathieu Thevenin, Gwenolé Corre, CEA Tech Pays-de-la-Loire (DP2L), CEA Tech en régions (CEA-TECH-Reg), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Soutien financier de la Région des Pays de la Loire dans le cadre de la convention d'expérimentation Etat-CEA relative à la création par le CEA de nouvelles plates-formes régionales de transfert de technologique (PRTT)., Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), CEA Tech Pays-de-la-Loire, Université Paris-Saclay-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Institut d'Electronique et de Télécommunications de Rennes (IETR), and Nantes Université (NU)-Université de Rennes 1 (UR1)
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Computer science ,Design space exploration ,02 engineering and technology ,MPSoC ,reliability evaluation ,Software reliability ,multiprocessor system-on-chip ,Hardware ,Component (UML) ,system-on-chip ,0202 electrical engineering, electronic engineering, information engineering ,System on a chip ,Instrumentation (computer programming) ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,DSE approach ,Reliability (statistics) ,instrumentation ,Fault tolerant systems ,Electronic architecture ,business.industry ,Fault tolerance ,meta-model ,020202 computer hardware & architecture ,Metamodeling ,[SPI.TRON]Engineering Sciences [physics]/Electronics ,multiprocessing systems ,Embedded system ,MPSoC design ,020201 artificial intelligence & image processing ,design-space-exploration ,business ,Unified modeling language ,Software - Abstract
International audience; When designing a Multi-Processor System-on-Chip (MPSoC), a very large range of design alternatives arises from a huge space of possible design options and component choices. Literature proposes numerous Design-Space-Exploration (DSE) approaches which mainly focus on cost optimization. In this paper, we present a DSE approach which mainly focuses on the reliability of the whole design. This approach is based on a meta-model of Multi-Processor System-on-Chips (MPSoCs) which integrates the reliability evaluation. We develop a tool that allows designers to describe and optimize their platform based on the proposed meta-model. The results obtained for an MPSoC is presented, including the improved overall reliability of the system thanks to the automatic selection of the fault tolerance strategies for each component.
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- 2017
25. Quantitative characterization of agglomerate abrasion in a tumbling blender by using the Stokes number approach
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Ricardo Hooijmaijers, Tofan A Willemsz, Tien Thanh Nguyen, Kees van der Voort Maarschalk, Herman Vromans, Henderik W. Frijlink, Pharmaceutical Technology and Biopharmacy, and Biopharmaceuticals, Discovery, Design and Delivery (BDDD)
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velocity ,Materials science ,porosity ,surface property ,Abrasion (mechanical) ,Chemistry, Pharmaceutical ,Pharmaceutical Science ,Mineralogy ,agglomerates ,tumbling blender ,Aquatic Science ,tumbling blending ,chemistry.chemical_compound ,Transition point ,Drug Discovery ,Composite material ,Porosity ,Ecology, Evolution, Behavior and Systematics ,Stokes number ,stokes ,density ,Ecology ,article ,Rotational speed ,General Medicine ,agglomerate abrasion ,Microcrystalline cellulose ,Models, Chemical ,Volume (thermodynamics) ,chemistry ,priority journal ,Agglomerate ,pharmacological parameters ,dry-mixing ,Powders ,Agronomy and Crop Science ,microcrystalline cellulose ,mathematical model ,Research Article - Abstract
Removal of microcrystalline cellulose agglomerates in a dry-mixing system (lactose, 100 M) predominantly occurs via abrasion. The agglomerate abrasion rate potential is estimated by the Stokes abrasion (StAbr) number of the system. The StAbrnumber equals the ratio between the kinetic energy density of the moving powder bed and the work of fracture of the agglomerate. Basically, the StAbrnumber concept describes the blending condition of the dry-mixing system. The concept has been applied to investigate the relevance of process parameters on agglomerate abrasion in tumbling blenders. Here, process parameters such as blender rotational speed and relative fill volumes were investigated. In this study, the StAbrapproach revealed a transition point between abrasion rate behaviors. Below this transition point, a blending condition exists where agglomerate abrasion is dominated by the kinetic energy density of the powder blend. Above this transition point, a blending condition exists where agglomerates show (undesirable) slow abrasion rates. In this situation, the blending condition is mainly determined by the high fill volume of the filler. © 2012 American Association of Pharmaceutical Scientists.
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- 2013
26. Quantitative transcript analysis of the inducible expression system pSIP: comparison of the overexpression of Lactobacillus spp. -galactosidases in Lactobacillus plantarum
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Dietmar Haltrich, Philipp Schmelzer, Geir Mathiesen, Thu-Ha Nguyen, Vincent G. H. Eijsink, Thomas Maischberger, Tien-Thanh Nguyen, and Clemens K. Peterbauer
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Limosilactobacillus reuteri ,Transcription, Genetic ,RNA Stability ,Genetic Vectors ,lcsh:QR1-502 ,Gene Dosage ,Bioengineering ,Applied Microbiology and Biotechnology ,lcsh:Microbiology ,Pheromones ,Plasmid ,Lactobacillus acidophilus ,Gene expression ,RNA, Messenger ,Promoter Regions, Genetic ,Gene ,Regulator gene ,Genetics ,Expression vector ,biology ,Research ,food and beverages ,Gene Expression Regulation, Bacterial ,beta-Galactosidase ,biology.organism_classification ,Molecular biology ,Recombinant Proteins ,Lactobacillus reuteri ,Fermentation ,Lactobacillus plantarum ,Plasmids ,Biotechnology - Abstract
Background Two sets of overlapping genes, lacLMReu and lacLMAci, encoding heterodimeric β-galactosidases from Lactobacillus reuteri and Lactobacillus acidophilus, respectively, have previously been cloned and expressed using the pSIP vector system and Lactobacillus plantarum WCSF1 as host. Despite the high similarity between these lacLM genes and the use of identical cloning and expression strategies, strains harboring lacLMReu produced about twenty-fold more β-galactosidase than strains containing lacLMAci. Results In this study, the plasmid copy numbers (PCN) of expression vectors pEH9R (lacLMReu) and pEH9A (lacLMAci) as well as the transcription levels of both lacLM genes were compared using quantitative PCR methods. Analyses of parallel fermentations of L. plantarum harboring either pEH9R or pEH9A showed that the expression plasmids were present in similar copy numbers. However, transcript levels of lacLM from L. reuteri (pEH9R) were up to 18 times higher than those of lacLM from L. acidophilus (pEH9A). As a control, it was shown that the expression levels of regulatory genes involved in pheromone-induced promoter activation were similar in both strains. Conclusion The use of identical expression strategies for highly similar genes led to very different mRNA levels. The data indicate that this difference is primarily caused by translational effects that are likely to affect both mRNA synthesis rates and mRNA stability. These translational effects thus seem to be a dominant determinant for the success of gene expression efforts in lactobacilli.
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- 2011
27. Immobilization of ß-Galactosidases from Lactobacillus on Chitin Using a Chitin-Binding Domain.
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Mai-Lan Pham, Leister, Tatjana, Nguyen, Hoang Anh, Bien-Cuong Do, Anh-Tuan Pham, Haltrich, Dietmar, Yamabhai, Montarop, Thu-Ha Nguyen, and Tien-Thanh Nguyen
- Published
- 2017
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28. A novel combining classifier method based on Variational Inference.
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Tien Thanh Nguyen, Thi Thu Thuy Nguyen, Xuan Cuong Phamc, and Alan Wee-Chung Liewa
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BAYESIAN analysis , *GAUSSIAN distribution , *MAXIMUM likelihood statistics , *MACHINE learning , *PATTERN recognition systems , *IMAGE fusion - Abstract
In this paper, we propose a combining classifier method based on the Bayesian inference framework. Specifically, the outputs of base classifiers (called Level1 data or meta-data) are utilized in a combiner to produce the final classification. In our ensemble system, each class in the training set induces a distribution on the Level1 data, which is modeled by a multivariate Gaussian distribution. Traditionally, the parameters of the Gaussian are estimated using a maximum likelihood approach. However, maximum likelihood estimation cannot be applied since the covariance matrix of Level1 data of each class is not full rank. Instead, we propose to estimate the multivariate Gaussian distribution of Level1 data of each class by using the Variational Inference method. Experiments conducted on eighteen UCI Machine Learning Repository datasets and a selected 10-class CLEF2009 medical imaging database demonstrated the advantage of our method compared with several well-known ensemble methods. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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29. Homodimeric β-Galactosidase from Lactobacillus delbrueckii subsp. bulgaricus DSM 20081: Expression in Lactobacillus plantarum and Biochemical Characterization.
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Tien-Thanh Nguyen, Hoang Anh Nguyen, Arreola, Sheryl Lozel, Mlynek, Georg, Djinović-Carugo, Kristina, Mathiesen, Geir, Thu-Ha Nguyen, and Haltrich, Dietmar
- Published
- 2012
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30. Unveiling the antibacterial potential of nature-inspired material for designing food-related coatings
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Yen Dang, Khuong Ba Dinh, Tien Thanh Nguyen, and The Hy Duong
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antibacterial ,antimicrobial ,hierarchical structures ,bio-inspired ,biomimetic ,Technology - Abstract
The escalating challenge of antibiotic resistance has driven the innovation of new antibacterial and antifouling materials. Recent developments focus on nature-inspired topographical engineering and nanostructured surfaces to combat resistant bacteria. This review discusses these advances, emphasizing the potential of nanoantibiotics and biopolymers. Nanoantibiotics revitalize drug effectiveness by encapsulating them in nanoparticles, presenting a new strategy to fight pathogens. Biopolymers, eco-friendly and biodegradable, emerge as a sustainable alternative, with applications in food safety and beyond. The exploration of these materials signifies a leap in design, fabrication, and the possibility of cost-effective, large-scale production, highlighting a promising avenue for commercial applications to tackle antibiotic resistance and biofouling effectively.
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- 2024
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31. A practical approach to nutritional intervention for people with chronic kidney disease in Vietnam.
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Lan Huong Thi Nguyen, Anh Kim Dang, Giang Thu Nguyen, Anh Minh Tran, Tien Thanh Nguyen, Phuong Thi Duong, Ha Ngoc Vu, and Huong Thi Le
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CHRONIC kidney failure , *NUTRITIONAL assessment , *NUTRITIONAL status , *NUTRITION counseling , *RENAL replacement therapy , *DIETARY patterns , *FATIGUE (Physiology) - Abstract
Background and Objectives: A comprehensive nutritional management is necessary for favourable outcomes in patients with chronic kidney disease (CKD). We aimed to assess the changes in nutritional status and disease progression with nutritional management where renal replacement therapy (RRT) was not in place. Methods and Study Design: A quasi-experiment intervention was conducted on 70 CKD patients at stages 3-5 from July to December 2022. Participants were excluded if they underwent RRT, including dialysis (hemodialysis or peritoneal dialysis), or kidney transplantation. The nutritional regimen covered nutritional counseling, samples of the dietary menu, and supplement products. We evaluated nutritional status using Subjective Global Assessment (SGA) scale and sub-clinical blood test at T0 (hospital admission) and T1 (two weeks after the admission or 24 hours before the discharge). Results: After the intervention, the number of patients classified as malnutrition or at risk of malnourished reduced significantly (65.7% to 54.3% and 25.7% and 5.7%, respectively). The serum concentration of urea, creatinine and parathyroid hormone decreased remarkably, especially in patients receiving nutritional management. In the intervention group, the dietary pattern provided increased intakes of calcium and iron at T1, while phosphorus, sodium and potassium decreased after follow-up. Nausea/vomiting, loss of appetite, tiredness and sleep disorders were improved in the intervention compared to the control group. Conclusions: Nutritional therapy enhanced the nutritional status, and quality of dietary and renal function in CKD patients without RRT. Applying nutrition education and treatment at an early stage can slow CKD progression, which should be applicable elsewhere in Vietnam. [ABSTRACT FROM AUTHOR]
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- 2024
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32. A Proposal to Evaluate Drought Characteristics Using Multiple Climate Models for Multiple Timescales.
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Tien Thanh, Nguyen
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ATMOSPHERIC models ,DROUGHTS ,METEOROLOGICAL precipitation ,SIMULATION methods & models ,HYDROLOGIC cycle - Abstract
This study presents a method to investigate meteorological drought characteristics using multiple climate models for multiple timescales under two representative concentration pathway (RCP) scenarios, RCP4.5 and RCP8.5, during 2021–2050. The methods of delta change factor, unequal weights, standardized precipitation index, Mann–Kendall and Sen's slope are proposed and applied with the main purpose of reducing uncertainty in climate projections and detection of the projection trends in meteorological drought. Climate simulations of three regional climate models driven by four global climate models are used to estimate weights for each run on the basic of rank sum. The reliability is then assessed by comparing a weighted ensemble climate output with observations during 1989–2008. Timescales of 1, 3, 6, 9, 12, and 24 months are considered to calculate the standardized precipitation index, taking the Vu Gia-Thu Bon (VG-TB) as a pilot basin. The results show efficient precipitation simulations using unequal weights. In the same timescales, the occurrence of moderately wet events is smaller than that of moderately dry events under the RCP4.5 scenario during 2021–2050. Events classified as "extremely wet", "extremely dry", "very wet" and "severely dry" are expected to rarely occur under the RCP8.5 scenario. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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33. Antibacterial Electrospun Membrane with Hierarchical Bead-on-String Structured Fibres for Wound Infections
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Yu Xuan Fong, Catherine Pakrath, Fathima Shana Pattar Kadavan, Tien Thanh Nguyen, Trong Quan Luu, Borislav Stoilov, Richard Bright, Manh Tuong Nguyen, Neethu Ninan, Youhong Tang, Krasimir Vasilev, and Vi Khanh Truong
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nanofibres ,polycaprolactone ,silk sericin ,biocompatible ,biodegradable ,natural polymer ,Chemistry ,QD1-999 - Abstract
Chronic wounds often result in multiple infections with various kinds of bacteria and uncontrolled wound exudate, resulting in several healthcare issues. Advanced medicated nanofibres prepared by electrospinning have gained much attention for their topical application on infected chronic wounds. The objective of this work is to enhance the critical variables of ciprofloxacin-loaded polycaprolactone-silk sericin (PCL/SS-PVA-CIP) nanofibre production via the process of electrospinning. To examine the antibacterial effectiveness of PCL/SS-PVA-CIP nanocomposites, the material was tested against P. aeruginosa and S. aureus. The combination of PCL/SS-PVA-CIP exhibited potent inhibitory properties, with the most effective concentrations of ciprofloxacin (CIP) being 3 μg/g and 7.0 μg/g for each bacterium, respectively. The biocompatibility was evaluated by conducting cell reduction and proliferation studies using the human epidermal keratinocyte (HaCaT) cells and human gingival fibroblasts (HGFs) in vitro cell lines. The PCL/SS-PVA-CIP showed good cell compatibility with HaCaT and HGF cells, with effective proliferation even at antibiotic doses of up to 7.0 μg/g. The drug release effectiveness of the nanocomposites was assessed at various concentrations of CIP, resulting in a maximum cumulative release of 76.5% and 74.4% after 72 h for CIP concentrations of 3 μg/g and 7 μg/g, respectively. In summary, our study emphasizes the possibility of combining silk sericin (SS) and polycaprolactone (PCL) loading with CIP nanocomposite for wound management.
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- 2024
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34. Heterologous expression of a recombinant lactobacillal β-galactosidase in Lactobacillus plantarum: effect of different parameters on the sakacin P-based expression system
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Barbara Geiger, Dietmar Haltrich, Hoang-Minh Nguyen, Tien-Thanh Nguyen, Vincent G. H. Eijsink, Thu-Ha Nguyen, Geir Mathiesen, and Clemens K. Peterbauer
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Genetic Vectors ,Bioengineering ,Applied Microbiology and Biotechnology ,law.invention ,Bacterial Proteins ,Bacteriocins ,Bacteriocin ,law ,Inducer ,2. Zero hunger ,chemistry.chemical_classification ,biology ,Research ,Temperature ,food and beverages ,Gene Expression Regulation, Bacterial ,Hydrogen-Ion Concentration ,beta-Galactosidase ,biology.organism_classification ,Recombinant Proteins ,Anti-Bacterial Agents ,Lactobacillus reuteri ,Glucose ,Enzyme ,Biochemistry ,chemistry ,Recombinant DNA ,Fermentation ,Heterologous expression ,Lactobacillus plantarum ,Biotechnology - Abstract
Background: Two overlapping genes lacL and lacM (lacLM) encoding for heterodimeric β-galactosidase from Lactobacillus reuteri were previously cloned and over-expressed in the food-grade host strain Lactobacillus plantarum WCFS1, using the inducible lactobacillal pSIP expression system. In this study, we analyzed different factors that affect the production of recombinant L. reuteri β-galactosidase. Results: Various factors related to the cultivation, i.e. culture pH, growth temperature, glucose concentration, as well as the induction conditions, including cell concentration at induction point and inducer concentration, were tested. Under optimal fermentation conditions, the maximum β-galactosidase levels obtained were 130 U/mg protein and 35–40 U/ml of fermentation broth corresponding to the formation of approximately 200 mg of recombinant protein per litre of fermentation medium. As calculated from the specific activity of the purified enzyme (190 U/mg), β-galactosidase yield amounted to roughly 70% of the total soluble intracellular protein of the host organism. It was observed that pH and substrate (glucose) concentration are the most prominent factors affecting the production of recombinant β-galactosidase. Conclusions: The over-expression of recombinant L. reuteri β-galactosidase in a food-grade host strain was optimized, which is of interest for applications of this enzyme in the food industry. The results provide more detailed insight into these lactobacillal expression systems and confirm the potential of the pSIP system for efficient, tightly controlled expression of enzymes and proteins in lactobacilli.
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35. The role of nutritional risk evaluation in predicting adverse outcomes among patients with severe COVID-19 in Vietnam
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Lan Huong Thi Nguyen, Anh Kim Dang, Tien Viet Tran, Hai Thanh Phan, Dao Anh Thi Doan, Lien Bao Thi Nguyen, Anh Minh Tran, Tung Dinh Do, Thang Ba Nguyen, Tien Thanh Nguyen, Binh Huy Nguyen, and Huong Thi Le
- Subjects
nutritional status ,COVID-19 ,Vietnam ,Nutritional Risk Screening (NRS) ,The Global Leadership Initiative on Malnutrition (GLIM) ,Prognostic Nutritional Index (PNI) ,Nutrition. Foods and food supply ,TX341-641 - Abstract
IntroductionAs sufficient nutrition helps alleviate catabolic stress and modulate the systemic inflammatory response of the body, it plays an indispensable role in the good prognosis of critically ill patients. Thus, this study aimed to investigate the malnutrition of patients with severe COVID-19 and its association with adverse treatment outcomes.MethodsWe conducted a retrospective cross-sectional study in two provincial hospitals in Hanoi from February to April 2022. Participants were patients with severe COVID-19 admitted to the Intensive Care Unit (ICU). Malnutrition risk were evaluated by Nutritional Risk Screening-2002 (NRS), Global Leadership Initiative on Malnutrition (GLIM), Prognostic Nutritional Index (PNI), and the adverse prognosis was assessed by Acute Physiology and Chronic Health Evaluation II (APACHE II). The multivariate receiver-operating characteristic (ROC) curve was applied to estimate the predictive ability of those criteria regarding worse treatment results.ResultsThe percentages of malnutrition measured by NRS, GLIM, PNI, and BMI were 62.6, 51.5, 42.9, and 16.6%, respectively. Patients with more severe malnutrition assessed by GLIM, PNI, and having above target fasting blood glucose (FBG) (≥10.0 mmol/L) were more likely to have higher APACHE scores. PNI had a better diagnostic performance than NRS and BMI (AUC = 0.84, 0.81, and 0.82, respectively). In addition, FBG revealed a good prognostic implication (AUC = 0.84).ConclusionA relatively high percentage of patients experienced moderate and severe malnutrition regardless of screening tools. Individuals at higher risk of malnutrition and high FBG were predicted to have more adverse treatment outcomes. It is recommended that nutritional screening should be conducted regularly, and personalizing nutritional care strategies is necessary to meet patients’ nutrient demands and prevent other nutrition-related complications.
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- 2023
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36. The Effect of Cellulose Fibre Length on the Efficiency of an Intumescent Flame Retardant System in Poly(lactic acid)
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Kata Enikő Decsov, Bettina Ötvös, Thuy Tien Thanh Nguyen, and Katalin Bocz
- Subjects
cellulose ,fibre length ,intumescence ,poly(lactic acid) ,melamine polyphosphate ,Physics ,QC1-999 - Abstract
In the flame retardancy of the biopolymer matrix and natural fibre reinforcement containing green composites, researchers face multiple challenges, such as low thermal stability, the candlewick effect of fibres and compatibility issues. Cellulosic fibres have been shown to have char-promoting properties and to advantageously interact with intumescent systems. In this work, melamine-polyphosphate was combined with neat or flame-retardant-treated cellulosic fibres differing in fibre length to obtain intumescent flame retarded poly(lactic acid) composites. The effect of the cellulose fibre length was evaluated in both forms. The structure-property relationships were evaluated by thermal and flammability test methods. It was found that the formation and the structure of the fire-protecting char are influenced by the length of the cellulose fibres, and thus it noticeably affects the effectiveness of the flame-retardant system. Cellulose fibres with an average length of 30–60 µm were found to contribute the best to the formation of an integrated fibrous-intumescent char structure with enhanced barrier characteristics.
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- 2023
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37. Curcuminoid Co-Loading Platinum Heparin-Poloxamer P403 Nanogel Increasing Effectiveness in Antitumor Activity
- Author
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Ngoc The Nguyen, Quynh Anh Bui, Hoang Huong Nhu Nguyen, Tien Thanh Nguyen, Khanh Linh Ly, Ha Le Bao Tran, Vu Nguyen Doan, Tran Thi Yen Nhi, Ngoc Hoa Nguyen, Ngoc Hao Nguyen, Ngoc Quyen Tran, and Dinh Trung Nguyen
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poloxamer P403 ,multi-drug delivery ,heparin ,MCF-7 ,nanogel ,Science ,Chemistry ,QD1-999 ,Inorganic chemistry ,QD146-197 ,General. Including alchemy ,QD1-65 - Abstract
Nanosized multi-drug delivery systems provide synergistic effects between drugs and bioactive compounds, resulting in increased overall efficiency and restricted side effects compared to conventional single-drug chemotherapy. In this study, we develop an amphiphilic heparin-poloxamer P403 (HP403) nanogel that could effectively co-load curcuminoid (Cur) and cisplatin hydrate (CisOH) (HP403@CisOH@Cur) via two loading mechanisms. The HP403 nanogels and HP403@CisOH@Cur nanogels were closely analyzed with 1H-NMR spectroscopy, FT-IR spectroscopy, TEM, and DLS, exhibiting high stability in spherical forms. In drug release profiles, accelerated behavior of Cur and CisOH at pH 5.5 compared with neutral pH was observed, suggesting effective delivery of the compounds in tumor sites. In vitro studies showed high antitumor activity of HP403@CisOH@Cur nanogels, while in vivo assays showed that the dual-drug platform prolonged the survival time of mice and prevented tail necrosis. In summary, HP403@CisOH@Cur offers an intriguing strategy to achieve the cisplatin and curcumin synergistic effect in a well-designed delivery platform that increases antitumor effectiveness and overcomes undesired consequences caused by cisplatin in breast cancer treatment.
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- 2022
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38. ELEMENTLERİN JEOKİMYASAL BİRLİKLERİNDE UZAMSAL KÜME VE AYKIRI DEĞERLERİN BELİRLENMESİ: JUIRUI BAKIR MADENİ BÖLGESİNDEN BİR ÖRNEK
- Author
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Tien Thanh NGUYEN, Danh Tuyen VU, Le Hung TRINH, and Thi Le Hang NGUYEN
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Spatial Outliers ,Spatial Clusters ,Spatial Variability ,Local Moran Statistic ,Geochemistry ,Uzamsal Aykırı Değer ,Uzamsal Kümeler ,Uzamsal Değişkenlik ,Yersel Moran İstatistiği ,Jeokimya ,Mineralogy ,QE351-399.2 - Abstract
Jeokimyasal verilerin saha dağılım desenlerinin belirlenmesi çalışmalarında uzamsal küme ve aykırı değerler büyük önem taşır. Bunlar, sadece cevherleşmenin temel özelliklerini değil, aynı zamanda maden yatağının ve cevher mineralinin alansal dağılımını da karakterize ederler. Bu çalışmada, çok değişkenli verinin alansal dağılım deseni konusunda yeni bir yöntem tanıtılacak olup bu yöntemde stabil Mahalanobis uzaklığı ile lokal Moran’s I1 değeri baz alınmıştır. Uzamsal matriksi oluştururken, aralığı belirlemek üzere öncelikle Moran’s I uzamsal korelogramı kullanılmıştır. Daha sonra, belirli bir elementler topluluğu için stabil Mehalanobis aralığı hesaplanmıştır. Son olarak, hem uzamsal birlik derecesini ölçmek hem de, uzamsal küme ve aykırı değerler dahil olmak üzere Cu, Au, Mo, Ag, Pb, Zn, As ve Sb birliklerinin uzamsal dağılım desenlerini belirlemek için yersel Moran’s I1 istatistiği uygulanmıştır. Hem ham veri hem de Box-Cox dönüşüm verisi üzerinde altı değişik ölçekte (2km, 4km, 6km, 8km, 10km ve 12km) uzamsal desen analizi yapılmıştır. Elde edilen sonuçlar, Moran’s I1 ve stabil Mahalanobis ile tanımlanan uzamsal küme ve uzamsal aykırı değer alanlarının nesnel gerçeklik ile uyum sağladıklarını, ayrıca çalışma alanında bilinen maden yatakları ile de uyumlu bir ilişki gösterdiklerini ortaya koymuştur.
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- 2016
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39. Simultaneous liquefaction, saccharification and fermentation at very high gravity of rice at pilot scale for potable ethanol production and distillers dried grains composition.
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Son Chu-Ky, Thi-Hoan Pham, Kim-Lien T. Bui, Tien-Thanh Nguyen, Kim-Dang Pham, Hoai-Duc T. Nguyen, Hong-Nga Luong, Viet-Phu Tu, Thanh-Hang Nguyen, Phu-Ha Ho, and Thanh-Mai Le
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FERMENTATION , *RICE processing , *LIQUEFACTION (Physics) , *ETHANOL , *AMYLASES - Abstract
In this work, a simultaneous liquefaction, saccharification, and fermentation (SLSF) process at very high gravity (VHG) of broken rice for potable ethanol production was developed at pilot scale. The SLSF-VHG process was performed in a unique fermenter, at 30 °C. Rice flour (RF) was dissolved in tap water to reach 311.5 g/1 dry matter and then the mixture was simul-taneousely liquefied, saccharified, and fermented. Thanks to the addition of a raw starch hydrolyzing enzyme containing a mixture of alpha-amylase and gluco-amylase (Stargen 002 at 991.8 GAU/kg RF), gluco-amylase (Amigase Mega L at 0.035% w/w), protease (Fermgen at 600 SAPU/kg RF), active dry yeast Saccharomyces cereuisiae (Red Ethanol at 3.5 x 107 cells/ml), KH2PO4 (4.8mM), and urea (16.0 mM). Under these conditions, the SLSF-VHG process finished after 120 h and achieved an ethanol content of 17.6% v/v corresponding to 86.3% of the theoretical ethanol yield. We scaled up this SLSF process at very high gravity at pilot scale (251) and achieved an ethanol content of 17.0% v/v corresponding to a yield of 83.2% of the theoretical ethanol yield. Rice-based distillers dried grains (DDG) was produced from the whole stillage of SLSF process at very high gravity by being plate-filtered and dried. The obtained DDG had high contents of crude protein (47.5%) and fibers (15.8%). Our results suggest, the SLSF under VHG condition of broken rice as well as the recovery of protein-rich DDG could have a great potential for the ethanol and animal feeding industry in Vietnam. [ABSTRACT FROM AUTHOR]
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- 2016
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