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Antibiofilm activity of alpha-mangostin loaded nanoparticles against Streptococcus mutans

Asian Pacific Journal of tropical Biomedicine 2020年第7期10卷 325-332页

作者： Phuong t.M.Nguyen Minh t.H.Nguyen Lien t.Quach Phuong t.M.Nguyen Lam L.Nguyen Dong V.Quyen Institute of Biotechnology Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadHanoiVietnam Institute of graduate University of Science and technology Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadHanoiVietnam University of Science and technology of Hanoi Vietnam Academy of Science and Technology18-Hoang Quoc Viet RoadCau GiayHanoiVietnam

Objective:to investigate the antibiofilm activity of alphamangostin(AMg)loaded nanoparticle(nano AMg)against dental caries pathogen Streptococcus ***:AMg was isolated from the peels of garcinia mangostana *** silica gel columns and chemically analysed by high performance liquid chromatography and nuclear magnetic *** AMg was prepared using the solvent evaporation method combined with high-speed *** nanoparticles were characterized using dynamic light scattering,field emission scanning electron microscopy(fe-SEM)and Fourier transform infrared spectroscopy(FtIR).the toxicity of nano AMg in fibroblast NIH/3 t3 cell line was determined using Mtt *** antibiofilm effect of nano AMg was determined through the evaluation of biofilm formation by Streptococcus mutans using a 96-well *** biomass was quantified using crystal *** viability was observed under confocal microscopy using LIVE/DEAD Bac Light ***,gene expression was determined by quantitative real-time PCR and membrane permeabilization activity by measuring the uptake of o-nitrophenol-β-***:Nano AMg size was in a range of 10-50 nm with a polydispersity index ofta potential value of-35.2 m *** size and the incorporation of AMg in the nanoparticles were confirmed by fe-SEM and FtIR *** IC50 values of the test agents on NIH/3 t3 cells were(9.80±0.63)μg/m L for AMg and(8.70±0.81)μg/m L for nano AMg,while no toxicity was generated from excipients used to prepare *** the early stage of biofilm formation,treatment with 6.25μmol/L nano AMg caused a reduction in biofilm biomass up to 49.1%,compared to 33.4%for *** contrast,biofilms at the late stage were more resistant to the test *** 96μmol/L(=10×MIC),nano AMg reduced only 20.7%of biofilm biomass while AMg did not showany *** of gtf B and gtf C genes involved in biofilm formation were down-regulated 3.3 and 12.5 folds,res

关键词： Alpha-mangostin Nanoparticle Antibiofilm activity Streptococcus mutans

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Antimicrobial susceptibility testing in veterinary medicine:performance,interpretation of results,best practices and pitfalls

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One Health Advances 2023年第1期1卷 62-77页

作者： Andrea t.feßler Yang Wang Claire R.Burbick Dubraska Diaz-Campos Virginia RFajt Sara D.Lawhon xian-Zhi Li Brian V.Lubbers Kelli Maddock Ron A.Miller Mark g.Papich Shabbir Simjee Michael t.Sweeney Jeffrey L.Watts Congming Wu Jianzhong Shen Stefan Schwarz Institute of Microbiology and Epizootics Centre for Infection MedicineSchool of Veterinary MedicineFreie Universität BerlinBerlinGermany Veterinary Centre for Resistance Research(tZR) Freie Universität BerlinBerlinGermany National Key Laboratory of Veterinary Public Health and Safety College of Veterinary MedicineChina Agricultural UniversityBeijingChina Key Laboratory of Animal Antimicrobial Resistance Surveillance Ministry of Agriculture and Rural AffairsCollege of Veterinary MedicineChina Agricultural UniversityBeijingChina Department of Veterinary Microbiology and Pathology College of Veterinary MedicineWashington State UniversityPullmanWAUSA Department of Clinical Sciences College of Veterinary MedicineThe Ohio State UniversityColumbusOHUSA texas A&M University School of Veterinary Medicine College StationTXUSA Veterinary Drugs Directorate Health CanadaOttawaONCanada Department of Clinical Sciences College of Veterinary MedicineKansas State UniversityManhattanKSUSA North Dakota State University Veterinary Diagnostic Laboratory FargoNDUSA U.S.Food and Drug Administration Center for Veterinary MedicineRockvilleMDUSA College of Veterinary Medicine North Carolina State UniversityRaleighNCUSA Elanco Animal Health HookUK Zoetis Inc.KalamazooMIUSA.

the performance of antimicrobial susceptibility testing(ASt)of bacteria and the interpretation of ASt results for bacteria isolated from animals are complex tasks which must be performed using standard published methodology and overseen by experts in clinical microbiology and in consultation with clinical ***,ASt has significant potential for errors and *** this review,we provide guidance on how to correctly perform ASt of bacteria isolated from animals and interpret the ASt *** emphasis is placed on the various approved or published methodologies for the different bacteria as well as the application of interpretive criteria,including clinical breakpoints and epidemiological cut-off values(ECVs/ECOFFs).Application of approved interpretive criteria and definitions of susceptible,susceptible dose-dependent,nonsusceptible,intermediate,and resistant for clinical breakpoints as well as wild-type and non-wildtype for ECVs,are explained and the difficulties resulting from the lack of approved clinical breakpoints for other bacteria,indications,and animal species is *** requirement of quality controls in any ASt approach is also *** addition,important parameters,often used in monitoring and surveillance studies,such as MIC50,MIC90,and testing range,are explained and criteria for the classification of bacteria as multidrug-resistant,extensively drug-resistant or pandrug-resistant are *** mistakes are presented and the means to avoid them are *** provide the most accurate ASt,one must strictly adhere to approved standards or validated methodologies,like those of the Clinical and Laboratory Standards Institute or other internationally accepted ASt documents and the detailed information provided therein.

关键词： Antimicrobial susceptibility testing Quality controls Clinical breakpoints Epidemiological cut-off values Multidrug resistance

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A POtENtIAL MEtHOD FOR DEtERMININg tHE HAZ PROPERtIES IN WELDS USINg tWO-MAtERIAL IMPRESSION CREEP tESt

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 591-596页

作者： W.Sun t.H.Hyde School of Mechanical Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD UKSchool of Mechanical Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD UK

the results of a theoretical and finite element (fe) investigation of a two-material impression creep test method, using a rectangular indenter, are presented. the method uses a general formulation for steady-state creep deformation for multi-material components in conjunction with the results of fe analyses. the practical application of the proposed technique, in determining the secondary creep properties of heat-affected zone (HAZ) materials in welds, for which conventional creep testing methods cannot be used, is considered. A number of numerical examples are used to describe solution procedures and to verify the method.

关键词： two-material impression creep general formulation creep property welds HAZ

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Magnetic Properties of Nd-fe-B Sintered Magnet Powders Recovered by Yb Metal Vapor Sorption

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Journal of Rare Earths 2004年第1期22卷 152-156页

作者： Horikawa t Itoh M Suzuki Shunji Machida K Collaborative Research Center for Advanced Science and technology Collaborative Research Center for Advanced Science and TechnologyCollaborative Research Center for Advanced Science and TechnologyCollaborative Research Center for Advanced Science and Technology Osaka University Osaka 565-0871 Japan Osaka University Osaka 565-0871 Japan Osaka University Osaka 565-0871 Japan Osaka University Osaka 565-0871 Japan

Fine ground powders of Nd-fe-B sintered magnet bulks (particle size=46～125 μm in diameter) were coated and alloyed with Yb metal by sorbing them. A significant recovery of the decreased magnetic properties of the ground powders (remanence B r=～0.95 t, coercivity H cj =～227 kA·m -1 and maximum energy product (BH) max=～48 8 kJ·m -3) was observed in accordance with increasing temperature up to 800 ℃. the sorbing temperature and time for Yb metal vapor were optimized and after heating at 800 ℃ for 90 min and annealing subsequently at 610 ℃ for 60 min, the B r, H cj and (BH) max values were increased to be 0.98 t, 712 kA·m -1 and 173 kJ·m -3, respectively. From the microstructural characterizations of resulting samples by using x-ray diffraction (xRD), scanning electron microscopy (SEM), and electron probe x-ray microanalyzer (EPMA), it is found that the sorbed Yb metal uniformly covers the surface and diffuses to the Nd-rich grain boundary of fine ground powders of Nd-fe-B sintered magnet bulks forming a (Nd,Yb)fe 2 phase.

关键词： metal materials Nd 2fe 14B sintered magnets metal vapor sorption magnetic properties recovery rare earths

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Fabrication and Magnetic Properties of fe60Co13Ni4Si11B12 Amorphous Soft Magnetic Powder Cores Using Ball-milled Powders

Fabrication and Magnetic Properties of Fe60Co13Ni4Si11B12 Am...

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第十一届中国钢铁年会

作者： Liu t. Lu K. Si J.J. Wang t. Zhu J. Wu Y.D. Hui x.D. State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

toroidal shape feCoNiSiB(at.%) alloy amorphous powder core has been firstly prepared using ball-milled powders and its magnetic properties has been *** powders were obtained after ball-milling for 12 h and annealing at 350℃ for 1 *** amorphous powder cores(outer diameter = 20 mm, inner diameter =16 mm, height =4 mm) were made of amorphous alloy powder below 150μm by cold *** core loss of the cores increase greatly with the increasing of frequency in frequency range of 30-400 *** core for Bm= 30 mt shows core loss of about 110 W/kg at 100 *** quality factor Q decreases with increasing frequency in frequency range of 30-400 *** core for Bm= 30 mt shows quality factor of about 30 at 100 *** permeability in the frequency range up to 500 kHz are approximately constant and the value is about *** present fe-based amorphous magnetic powder cores with excellent soft magnetic properties are a potential candidate for a variety of electronic system and industrial applications.

关键词： amorphous powder core annealing low core loss magnetic properties

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Performance of Red Onion （Bulb type） in Fully Converted Organic Area as Affected by Frequency of Organic fertilizer Application Combined with trichoderma spp,

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Journal of Agricultural Science and technology(B) 2016年第1期6卷 10-17页

作者： Jonathan Lucas galindez fe Ladiana Porciuncula Melchor Pagatpatan Pascua Samuel Macaraeg Claus Lani Lou Mar Agoy Lopez Ramon Magsaysay Center for Agricultural Resources and Environment Studies Central Luzon State University Science City ofMu~oz Nueva Ecija 3120 Philippines

the study was conducted to determine the viability of producing organic onion under the fully converted area of Ramon Magsaysay Center for Agricultural Resources and Environment Studies （RMC-ARES）, Central Luzon State University, Philippines. Specifically, the study aimed to establish the fi＇equency of organic fertilizer and trichoderma spp. application, employing split application, and determine the yield performance of red onion （bulb type）. the research was conducted for two consecutive dry seasons （2014 and 2015）. Red Creole variety was used with the following treatments： t1--organic fertilizer alone （8 ton/ha） at planting; t2--organic fertilizer （8 ton/ha） applied twice （at basal and 30 d after transplanting （DAt））; t3---organic fertilizer （8 ton/ha） applied twice （at basal and 30 DAt）＋ trichoderma spp. at the rate of 526 kg/ha applied at planting; t4----organie fertilizer at 8 ton/ha rate ＋ trichoderma spp. at the rate of 526 kg/ha, both applied twice （at planting and 30 DAt）; t5--organic fertilizer at 8 ton/ha rate applied twice （at planting and 30 DAt）＋ trichoderma spp. at the rate of 526 kg/ha applied thrice （at planting, 30 DAt and during bulb formation）. Results of the study showed that application of the recommended rate of organic fertilizer twice （at planting and 30 DAt）＋ three times application of trichoderma spp. （at planting, 30 DAt and during bulb formation） consistently produced bigger bulb during the first and second trial of the study, compared to other treatments evaluated. Consequently, higher marketable yield was produced with 15.33 ton/ha during the first trial and 14.50 ton/ha on the second trial.

关键词： Organic onion trichoderma spp. organic fertilizer split applieation.

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Bifunctional luminescent and magnetic core/shell type nanostructures fe_3O_4@CeF_3:tb^(3+)/SiO_2

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Journal of Rare Earths 2011年第12期29卷 1117-1122页

作者： M.Runowski t.grzyb S.Lis Department of Rare Earths Faculty of ChemistryAdam Mickiewicz University

A facile co-precipitation and microemulsion methods were applied to obtain core/shell type nanoparticles. Cerium fluoride doped with terbittrn（Ⅲ） ions supplied intensive green luminescence of the system. Due to the presence of magnetite nanoparticles as cores, the prod- uct was highly sensitive to external magnetic field. Both sorts of nanostructures were encapsulated by silica shell. Such external layer of inert oxide can potentially increase the resistance of prepared nanostructttres to thermal oxidation, aggressive agents, changing ofpH or destructive radiation. Morphology of the product was examined using transmission electron microscopy （tEM）. Formations of the core/shell type nanostructures were clearly seen in the tEM pictures. Powder x-ray diffraction （xRD） confirmed the structure of the products, their nanocrystallinity and amorphous nature of silica shell. Optical properties were investigated by measuring excitation and emission spectra. Such multifunctional luminescent and magnetic nanoparticles coated with easily functionalized silica shell could be applied in many field of science.

关键词： bifunctional nanoparticles magnetic nanoparticles luminescence core/shell rare earths

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浸渍硅胶薄层色谱板分离钴和镍及数字图像分析法定量(英文)

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色谱 2012年第10期30卷 1081-1088页

作者： P A MOHAMED NAJAR R g SONALI M t NIMJE K V RAMANA RAO Jawaharlal Nehru Aluminium Research Development and Design Centre

thin layer chromatography(tLC) of cobalt and nickel has been performed on silica gel layers induced with alkali mediated cellulose extract.A novel combination of 10% aqueous solutions of tween-20 and potassium thiocyanate in 1∶1(v/v) was identified as the best mobile phase for the selective separation of Co2+from Ni2+on the impregnated Silica gel g *** chromatographic characteristics of the cations were studied and the limits of detection as well as the limits of quantification for Co2+and Ni2+were *** quantitative estimation of the cations was achieved from the digital image analysis of respective *** proposed quantitative method was successfully applied with 0-0.50% error for the determination of Co2+from Ni2+in spiked samples of bauxite,soil and rock containing common cations such as Al3+,fe2+,ti4+,Zn2+,Mn2+,Cu2+,Cr6+,Mg2+,*** the optimized chromatographic conditions.

关键词： thin layer chromatography(tLC) cobalt nickel quantification digital image analysis

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Fabrication, modification and environmental applications of tiO2 nanotube arrays （tNtAs） and nanoparticles

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Frontiers of Chemical Science and Engineering 2012年第1期6卷 112-122页

作者： S. ROHANI t. ISIMJAN A. MOHAMED H. KAZEMIAN M. SALEM t. WANg Department of Chemical and Biochemical Engineering The University of Western Ontario London N6A 5B9 Canada

Among the semiconductors, titanium dioxide has been identified as an effective photocatalyst due to its abundance, low cost, stability, and superior electronic energy band structure. Highly ordered nanotube arrays of titania were produced by anodization and mild sonication. the band gap energy of the titania nanotube arrays was reduced to 2.6 eV by co-doping with fe, C, N atoms using an electrolyte solution containing K3fe（CN）6. the photo- conversion of phenol in a batch photoreactor increased to more than 18% based on the initial concentration of phenol by using a composite nanomaterial consisting of titania nanotube arrays and Pt/ZIF-8 nanoparticles. A layer-by- layer assembly technique for the deposition of titania nanoparticles was developed to fabricate air filters for the degradation of trace amounts of toluene in the air and preparation of superhyrophobic surfaces for oil-water separation and anti-corrosion surfaces.

关键词： tiO2 nanotube arrays and nanoparticles,anodization bandgap modification layer-by-layer deposi-tion oil-water separation

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Complete oxidation of 1,4-dioxane over zeolite-13x-supported fe catalysts in the presence of air

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Chinese Journal of Catalysis 2016年第2期37卷 240-249页

作者： C.Ramakrishna R.Krishna t.gopi g.Swetha Bijendra Saini S.Chandra Shekar Anchal Srivastava 国防研发局、防化装备评估设备(CDEF) 印度那格浦尔MH-441108

Zeolite-13x-supported fe（fe/zeolite-13x） catalysts with various fe contents were prepared by the wet impregnation *** catalysts were characterized by N2 adsorption-desorption isotherms to estimate the Brunauer-Emmett-teller surface areas and Barrett-Joyner-Hanlenda pore size distributions.x-ray diffraction,scanning electron microscopy,temperature-programmed reduction,and temperature-programmed desorption of NH3 were used to investigate the textural properties of the fe/zeolite-13 x *** catalytic activities were determined for the complete oxidation of1,4-dioxane using air as the oxidant in a fixed-bed flow reactor in the temperature range 100-400℃.the influences of various process parameters,such as reaction temperature,metal loading,and gas hourly space velocity（gHSV）,on the dioxane removal efficiency by catalytic oxidation were *** stability of the catalyst was tested at 400℃ by performing time-on-stream analysis for 50 *** fe/zeolite-13 x catalyst with 6 wt%fe exhibited the best catalytic activity among the fe/zeolite-13 x catalysts at 400℃ and a gHSV of 24000 h^（-1）,with 97%dioxane conversion and95%selectivity for the formation of carbon oxides（CO and CO2）.trace amounts（ 3%） of acetaldehyde,ethylene glycol monoformate,ethylene glycol diformate,1,4-dioxane-2-ol,1,4-dioxane-2-one,and 2-methoxy-1,3-dioxalane were also formed as degradation products.A plausible degradation mechanism is proposed based on the products identified by gC-MS analysis.

关键词： Iron Zeolite-13x 1 4-Dioxane Catalytic degradation Complete oxidation Degradation mechanism

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