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Anti-inflammatory effects of fatty acids isolated from Chromolaena odorata

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Asian Pacific Journal of Tropical Medicine 2011年第10期4卷 760-763页

作者： tran thi Hong Hanh Dan thi Thuy Hang Chau Van Minh Nguyen Tien Dat Institute of Marine Biochemistry Vietnam Academy of Science and Technology(VAST)

Objective:To identify inhibitors of nitric oxide production and NF-κB activity from Chromolaena odorata（***）.Methods:The compounds isolated from the aerial parts of *** by bioassay-guided fractionation were investigated for their inhibitory effects on the NO production and NF-κB activity in LPS-stimulated RAW264.7 ***:Six fatty acids （S）-coriolic acid（1）,（S）-coriolic acid methyl ester（2）,（5）-15,16-didehydrocoriolic acid（3）,（S）- 15,16-didehydrocoriolic acid methyl ester（4）,linoleamide（5） and linolenamide（6） were isolated. All compounds inhibited the NO production at concentrations consistent with those required for NF-κB *** 2 was the most active with the IC50 values of 5.22 and 5.73μM. The addition of a double bond in the fatty chain decreased the inhibitory effects while the methyl esterification increased the ***:The fatty acid components in *** with NF-κB inhibitory activity could explain the anti-inflammation property of this plant in traditional *** study could also contribute to the better use of *** for human health care.

关键词： Chromolaena odorata Asteraceae Fatty acid NF-κB Nitric oxide

CONVERGENCE RESULTS FOR NON-OVERLAP SCHWARZ WAVEFORM RELAXATION ALGORITHM WITH CHANGING tranSMISSION CONDITIONS

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Acta Mathematica Scientia 2022年第1期42卷 105-126页

作者： Minh-Phuong tran Thanh-Nhan NGUYEN Phuoc-Toan HUYNH nhu-Binh LY Minh-Dang NGUYEN Quoc-Anh HO Applied Analysis Research Group Faculty of Mathematics and StatisticsTon Duc Thang UniversityHo Chi Minh cityVietnam Department of Mathematics Ho Chi Minh City University of EducationHo Chi Minh cityVietnam Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh cityVietnam

In this paper,we establish a new algorithm to the non-overlapping Schwarz domain decomposition methods with changing transmission conditions for solving one dimensional advection reaction diffusion *** precisely,we first describe the new algorithm and prove the convergence results under several natural assumptions on the sequences of parameters which determine the transmission *** we give a simple method to estimate the new value of parameters in each *** interesting advantage of our method is that one may update the better parameters in each iteration to save the computational cost for optimizing the parameters after many *** some numerical experiments are performed to show the behavior of the convergence rate for the new method.

关键词： domain decomposition method Schwarz waveform relaxation algorithm advection reaction diffusion changing transmission conditions

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COVID-19 vaccination intention among healthcare workers in Vietnam

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Asian Pacific Journal of Tropical Medicine 2021年第4期14卷 159-164页

作者： Giao Huynh thien Thuan tran Han thi Ngoc Nguyen Le An Pham Faculty of Public Health University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh CityVietnam Infection Control Department University Medical Center Ho Chi Minh CityHo Chi Minh CityVietnam Family Medicine Training Center University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh CityVietnam

Objective:To assess the acceptance of coronavirus disease(COVID-19)vaccine among healthcare workers at two general hospitals in Vietnam when it is ***:A cross-sectional study was conducted using a convenience sampling from January to February 2021 among 410 healthcare workers at two general hospitals in Vietnam via a selfadministered questionnaire.A multivariable regression analysis was performed to determine predictors of vaccine acceptance including the demographic factors,COVID-19 knowledge,and vaccine beliefs based on the domains of Health Belief ***:Among 410 healthcare workers,76.10%showed vaccination *** of acceptance were determined that the group reporting as“vaccine acceptance”was more likely to be positive towards the perceived susceptibility and severity of COVID-19(OR 2.45;95%CI 1.48-4.06,P<0.05),perceived benefits of vaccination,and cues to action(OR 4.36;95%CI 2.35-8.09,and OR 5.49;95%CI 2.84-10.61,respectively,all P<0.001),but less likely to have the perceived barriers to vaccination(OR 0.19;95%CI 0.09-0.38;P<0.001)compared with the no acceptance ***,people who had a good knowledge regarding the severity of illness were 3.37 times more likely to have identified as vaccine acceptance(OR 3.37;95%CI 1.04-10.86,P<0.05).The demographic factors were also associated with willingness to receive the vaccine,with participants who were staff and received COVID-19 information from relatives were less likely to accept the vaccine over those who were doctors and not receiving information from relatives(OR 0.36;95%CI 0.13-0.96,and OR 0.37;95%CI 0.17-0.78,respectively,all P<0.05).Conclusions:A rate of willingness to get vaccinated against COVID-19 was relatively high with discrepancies between occupation,receiving information from relatives,knowledge toward the severity of illness,and the elements of Health Belief *** findings will provide information for the management authorities to develop relevant interv

关键词： Acceptance COVID-19 Healthcare workers Intention SARS-CoV-2 Vaccination

Indications for and techniques of keratoplasty at Vietnam National Institute of Ophthalmology

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 379-383页

作者： Pham Ngoc Dong Truong nhu Han Anthony J.Aldave hoang thi Minh Chau Vietnam National Institute of Ophthalmology HanoiVietnam Stein Eye Institute the University of California Los Angeles CA 90095-7003 USA

AIM： To report the indications for and techniques of corneal transplantation at Vietnam National Institute of Ophthalmology （VNIO） over a period of 12y （2002-2013）, METHODS： Records of patients who had undergone corneal transplantation at VNIO from January 1, 2002 to January 1, 2014 were reviewed to determine the indication for and type of corneal transplant performed. Patient age, gender, indication for corneal transplantation and surgical technique were recorded and analyzed. RESULTS： Corneal transplantation were underwent in 1390 eyes of 1278 patients with a mean age of 44.9±18.1y during the period under review. The most common indication was infectious corneal ulcer （n=670; 48.2%）, followed by corneal scar （n=333, 24.0% ）, corneal dystrophy （n=138, 9.9%） and failed graft （n=112, 8.1%）. Nearly all procedures performed were penetrating keratoplasty （n=1300, 93.5% ）, with a few lamellar keratoplasty procedures performed： lamellar keratoplasty （n=52, 3.7%）, Descemet＇s stripping automated endothelial keratoplasty （n =27, 1.9% ） and deep anterior lamellar keratoplasty （n =11, 0.8%）.CONCLUSION： While the most common indication for keratoplasty was infectious keratitis, nearly all indications for corneal transplantation were managed with penetrating keratoplasty, However, lamellar keratoplasty techniques, including deep anterior lamellar keratoplasty and Descemet＇s stripping automated endothelial keratoplasty, are being performed with increasing frequency for isolated stromal and endothelial disorders, respectively,

关键词： penetratingkeratoplasty, lamellarkeratoplasty endothelial keratoplasty indication for keratoplasty technique of keratoplasty

Upconversion luminescence of Gd2O3:Er3+and Gd2O3:Er3+/silica nanophosphors fabricated by EDTA combustion method

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Journal of Rare Earths 2019年第11期37卷 1126-1131页

作者： Le Quoc Minh tran Kim Anh Nguyen Duy Hung Pham thi Minh Chau Nguyen thi Quy Hai Ho Van Tuyen Vu thi Thai Ha Vu Duc Tu Wieslaw Strek Institute of Theoretical and Applied Research Duy Tan UniversityDa Nang 55000Viet Nam Advanced Institute for Science and Technology Hanoi University of Science and Technology1 Dai Co VietHai Ba TrungHanoiViet Nam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadCau Giay DistrictHanoiViet Nam Institute of Low Temperature and Structure Research Polish Academy of Science 2 OkolnaWroclawPoland

Gd2O3:Er^3+nanophosphors were fabricated by the combustion method in presence of Na2 ethylene diamine tetra acetic acid(EDTA-Na2)as fuel at not high temperature(≤350℃)within a very short time of 5 *** added concentration of Er^3+ions in Gd2O3 matrix was changed from 0.5 mol%to 5.0 mol%.The X-ray diffraction pattern of samples indicates the monoclinic structure of Gd2O3:Er^3+.The morphology and chemical composition analysis of the Gd2O3:Er^3+samples are characterized by a field emission scanning electron microscope(FESEM)and a Fourier-transform infrared spectrometer(FTIR).The photoluminescence(PL),photo luminescence excitation(PLE)and upconversion(UC)at room temperature of the prepared materials with different concentrations of Er^3+were *** PL of Gd2O3:Er^3+nanomaterials are shown in visible at 545,594,623,648,688 nm under excitation at 275 *** emission bands from transitions of Er^3+from 2P3/2 to 4F9/2 are observed,UC luminescent spectra of the Gd2O3:Er^3+/silica nanocomposites under 976 nm excitation show the bands at 548 and 670 *** influence of excitation power at 980 nm for transitions were measured and *** results indicate that the upconversion process of Gd2O3:Er^3+/silica is two photons absorption *** low temperature dependence of UC luminescent intensities of the main bands of Gd2O3:Er^3+was investigated towards development of a nanotemperature sensor in the range of 10-300 K.

关键词： Upconversion luminescence Gd2O3:Er3+ Gd2O3:Er3+/silica Nanophosphors EDTA combustion Rare earths

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Establishing the Method for Assessing Flood Vulnerability in Ho Chi Minh City, Vietnam A Case Study in District 6

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Journal of Environmental Science and Engineering(B) 2018年第2期7卷 72-82页

作者： tran thi Diem Loan Can Thu VOXI Nguyen Thanh Son Do thi Hong hoa Insitute for Environment and Resources Vietnam National University Ho Chi NinhHCM City 700000Vietnam Ho Chi Minh City University of Natural Resources and Environment HCM City 700000Vietnam Ha Noi University of Science Vietnam National University Ha NoiHa Noi 100000Vietnam Vietnam Academy of Science and Technology HaVoi 100000Vietnam

Urban flooding has impacted siginficantly on people＇s living： economic development, environmental pollution, etc.. It has been the serious problem of many cities in file world, especially in urban areas in developing countries because urbanization is too fast but lack of adaptive management planning and infrastructure. In Vietnam, the big cities, such as HCM （Ho Chi Minh） City, Hanoi, etc. have also been influenced severely by floods. By early 2017, HCM City has 171 flooded sites assigned by the district level; 40 submergence points assigned by Steering Center of Flooding Control Program, and 9 tidal flooded points. The paper will establish a suitable method for assessing flood vulnerability in HCM City from natural, social and environmental aspects. The results of a case study in District 6 show that there are four wards with high vulnerability and 10 wards with average vulnerability.

关键词： Vulnerability flooding District 6 HCM City.

A novel approach for synthesis of hierarchical mesoporous Nd2O3 nanomaterials

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Journal of Rare Earths 2017年第7期35卷 677-682页

作者： Le Huu Trinh Dinh Quang Khieu hoang Thai Long tran Thai hoa Duong Tuan Quang Nguyen Duc Cuong College of Sciences Hue University 77 Nguyen Hue Hue City Viet Nam Faculty of Hospitality and Tourism Hue University 22 Lam Hoang Hue CityViet Nam College of Education Hue University 34 Le LoL Hue City Viet Nam

A novel route to the fabrication of hierarchical mesoporous Nd_2O_3 nanostructures including nanospheres and nanoporous network was described. Their structure and morphology evolution of the as-synthesized materials were determined by various techniques such as scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transforminfrared spectra, nitrogen adsorption/desorption isotherm, and a formation mechanism was proposed. The results revealed that the Nd_2O_3 nanospheres had the diameter of 300 nm, which were composed of small primary nanoparticles（NPs） with the size of 10 nm. The nanoporous structure also formed the NPs of ca. 10 nm which were connected with each other to form a three-dimensional（3D） texture. this simple and mild approach to fabricate hierarchical mesoporous Nd_2O_3 nanostructures could be easily scaled up and potentially extended to synthesize other oxide hierarchical structures.

关键词： Nd2O3 hierarchical nanostructures nanospheres nanoporous network rare earths

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Evaluation of Weathering Performance of Rosin-Copper Based Treated Wood

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Journal of Renewable Materials 2022年第11期10卷 2765-2780页

作者： thi Thanh Hien Nguyen Nho Quyet tran thi Minh Nguyet Nguyen Hien Mai Trinh Xuan Phuong Le Trong Kien Nguyen College of Wood Industry and Interior Design Vietnam National University of ForestryHa NoiViet Nam College of Economics and Management Northeast Forestry UniversityHarbinChina

this study aimed to evaluate the effect of natural weathering on some surface characteristics and mechanical properties of Styrax wood treated with mixtures of 1.0%,2.0%,or 4.0%rosin sizing agent and 3%copper *** samples after treatment were exposed to outdoor conditions for one year and changes in color,glossiness,weight loss,compression strength parallel to grain(CSPG),modulus of rupture(MOR),and modulus of elasticity(MOE)were investigated after 6 and 12-month of natural *** results showed that rosin-copper treatment could improve color stability and gloss of samples after *** losses of all rosin-copper treated samples after 12 months of exposure were negligible compared with the untreated control *** addition,rosin-copper treatment enhanced the CSPG compared to untreated controls,but slightly decreased the MOR and MOE of Styrax wood before *** weathering factors induced a reduction for all strength properties,however,the decrease rate for strength properties of rosin-copper treated samples was negligible compared with the untreated control samples after 12-month natural weathering *** FTIR and SEM-EDX confirmed that the use of the rosin-copper formulations to impregnate wood could decrease the hazard of the copper preservative leaching into the environment,while also enhancing more resistance against weathering factors and other biotic factors.

关键词： Rosin-copper weathering color stability CSPG MOR MOE

A comparative analysis of weight-based machine learning methods for landslide susceptibility mapping in Ha Giang area

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Big Earth Data 2023年第4期7卷 1005-1034页

作者： Thanh Trinh Binh Thanh Luu trang Ha thi Le Duong Huy Nguyen Trong Van tran thi Hai Van Nguyen Khanh Quoc Nguyen Lien thi Nguyen Faculty of Computer Science Phenikaa UniversityYen NghiaHa DongHanoi 12116Vietnam Phenikaa Research and Technology Institute(PRATI) A&A Green Phoenix Group JSCNo.167 Hoang NganTrung HoaCau GiayHanoi 11313Vietnam Northwestern Geological Division General Department of Geology and Minerals of VietnamHanoiVietnam Youth union office Thuyloi University175 Tay SonDong DaHanoiVietnam Center of Remote Sensing and Geohazards Vietnam Institute of Geosciences and Mineral ResourcesHanoiVietnam

Landslide susceptibility maps (LSMs) are very crucial for planningpolicies in hazardous areas. However, the accuracy and reliability ofLSMs depend on available data and the selection of suitable *** study is conducted to produce LSMs by combinations of machinelearning methods and weighting techniques for Ha Giang province,Vietnam, where has limited data. In study area, we gather 11 landslideconditioning factors and establish a landslide inventory *** the weights of classes (or factors) is very important toprepare data for machine learning methods to generate LSMs. Wefrst use frequency ratio (FR) and analytic hierarchy process (AHP)techniques to generate the weights. Then, random forest (RF), supportvector machine (SVM), logistic regression (LR), and AHP methods arecombined with FR and AHP weights to yield accurate and reliableLSMs. Finally, the performance of these methods is evaluated by fivestatistical metrics, ROC and R-index. The empirical results have shownthat RF is the best method in terms of R-index and the five metrics, *** rate (0.9661), FP rate (0.0), ACC (0.9835), MAE (0.0046), and RMSE(0.0350) for this study area. this study opens the perspective of weightbasedmachine learning methods for landslide susceptibility mapping.

关键词： Landslide logistic regression random forest SvM Vietnam