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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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Enthalpy of mixing of Liquid Al-Cr and Cr-Ni Alloys

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Journal of materials Science & technology 2002年第2期18卷 167-170页

作者： P.Saltykov v.t.Witusiewicz 等 max-Planck-InstitutfuremetallforschungandUniveristaetStuttgart InstitutfuerNichtmetallischeAnorganischeMaterialienUnversityStuttgartPulvermetallurgischesLaboratoriumHeisenbergstr57056 max-Planck-I

the partial and the integral enthalpies of mixing of liquid Al-Cr and Ni-Cr binary alloys have been determined by high temperature isoperibolic calorimetry at 1723±5 K and 1729±5 K, respectively. the results were analytically described by the thermodynamically adapted power series (tAPS). the enthalpies of mixing values for both binary liquid melts are small and negative and in good agreement with the available literature data. minima of the mixing enthalpies of liquid Al-Cr and Ni-Cr alloys are -7.0 kJ·mol-1 at 46 at. pct Cr and -3.0 kJ·mol-1 at 37 at. pct Cr, respectively.

关键词： Al-Cr Cr-Ni Liquid alloys Enthalpy of mixing Isoperibolic calorimetry

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mobility of large clusters on a semiconductor surface:Kinetic monte Carlo simulation results

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Chinese Physics B 2016年第1期25卷 580-584页

作者： m Esen A t ttizemen m Ozdemir vocational School of Adana Cukurova UniversityAdana O1160Turkey Department of Science and mathematics Education Faculty of EducationCumhuriyet UniversitySivas 58140Turkey Department of Physics Cukurova UniversityAdana 01330Turkey

the mobility of clusters on a semiconductor surface for various values of cluster size is studied as a function of temperature by kinetic monte Carlo method. the cluster resides on the surface of a square grid. Kinetic processes such as the diffusion of single particles on the surface, their attachment and detachment to/from clusters, diffusion of particles along cluster edges are considered. the clusters considered in this study consist of 150-6000 atoms per cluster on average. A statistical probability of motion to each direction is assigned to each particle where a particle with four nearest neighbors is assumed to be immobile. the mobility of a cluster is found from the root mean square displacement of the center of mass of the cluster as a function of time. It is found that the diffusion coefficient of clusters goes as D = A（t）Na where N is the average number of particles in the cluster, A（t） is a temperature-dependent constant and a is a parameter with a value of about -0.64 〈 a 〈 -0.75. the value of a is found to be independent of cluster sizes and temperature values （170-220 K） considered in this study. As the diffusion along the perimeter of the cluster becomes prohibitive, the exponent approaches a value of -0.5. the diffusion coefficient is found to change by one order of magnitude as a function of cluster size.

关键词： diffusion constant cluster mobility monte Carlo method

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Some studies of the interaction between two two-level atoms and SU(1,1) quantum systems

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Chinese Physics B 2018年第10期27卷 116-122页

作者： t m El-Shahat m Kh Ismail Faculty of Science Al-Azhar University. Assiut 71524 Egypt

Herein, we present an approach to look for the best phenomenon to measure quantum correlation. the system of two isolated qubits each interacting with a single-mode cavity was theoretically created to study the quantum correlation. Some of the phenomena, such as the quantum discord and concurrence, were generated through such a system. the influences of initial state purity, qubit motion, and detuning parameters were discussed for the phenomena. these parameters for a specific value show that the behavior of phenomena are analogous. It is interesting to mention that some values of detuning undergo a sudden death of phenomena, and the quantum discord still captures the qubits quantum correlation. We predict that the quantum discord may be a better measure of quantum correlation than concurrence.

关键词： an isolated atom with a cavity SU (1,1) quantum discord concurrence

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Biochemical Factors Affecting the Quality of Products and the technology of Processing Deep-Sea Fish, the Giant Grenadier Albatrossia pectoralis

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Journal of Ocean University of China 2020年第3期19卷 681-690页

作者： PIvNENKO t.N. KARPENKO Yu.v. KRASHCHENKO v.v. POZDNYAKOvA Yu.m. ESIPENKO R.v. Far Eastern State technical Fisheries University Vladivostok 690087Russia

the composition of muscle tissues of a deep-sea species, the giant grenadier(Albatrossia pectoralis), and a mesopelagic species, the Alaska pollock(theragra chalcogramma), are compared. Grenadier is proved to have a higher moisture content(91.7%) and lower protein(7.4%) and lipid(0.3%) contents. the factors responsible for the softening and moisture separation during processing of grenadier are identified. Contents of some fractions of non-protein nitrogenous components, including trimethylamine oxide(tmAO) and free amino acids, are clarified. the proportion of the main myofibrillar proteins myosin and actin, which is considered as an indicator of efficiency of structure formation in fish muscle tissue during processing, is almost 20% lower in giant grenadier than in pollock. the effects of endogenous protease, Са^2+-AtPase and transglutaminase on the processes of autolysis, denaturation, and possibility of myofibrillar proteins cross-linking were also studied. the proposed technology of getting a nutritionally balanced, gel-like, ready-to-use foodstuff from grenadier fillet includes its enrichment with pollock muscle tissue and supplementing with a binary structure-forming agent containing collagen and chitosan. Nutritional value of the products is assessed by the method of biological assay and by determining the denaturation changes of myofibrillar proteins. the modes of fine mincing and thermal processing, as well as the shelf-life of the finished product are justified. the developed technology of producing a ready-to-eat food from giant grenadier will allow a more efficient use of this underutilized resource.

关键词： giant grenadier Alaska pollock myosin actin proteases AtPase transglutaminase softening structure formation ready-to-eat foodstuffs

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Geospatial analysis of forest fragmentation in Uttara Kannada District, India

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Forest Ecosystems 2016年第3期3卷 206-220页

作者： Ramachandra t v Bharath Setturu Subash Chandran Energy & Wetlands Research Group Center for Ecological Sciences（CES） Indian Institute of Science Centre for Sustainable technologies (astra) Bangalore Karnataka 560 012 India Centre for infrastructure Sustainable Transportation and Urban Planning（CiSTUP） Indian Institute of Science Bangalore Karnataka 560 012 India

Background： Landscapes consist of heterogeneous interacting dynamic elements with complex ecological, economic and cultural attributes. these complex interactions help in the sustenance of natural resources through bio-geochemical and hydrological cycling. the ecosystem functions are altered with changes in the landscape structure, Fragmentation of large contiguous forests to small and isolated forest patches either by natural phenomena or anthropogenic activities leads to drastic changes in forest patch sizes, shape, connectivity and internal heterogeneity, which restrict the movement leading to inbreeding among meta populations with extirpation of species. methods： Landscape dynamics are assessed through land use analysis by way of remote sensing data acquired at different time periods. Forest fragmentation is assessed at the pixel level through computation of two indicators, i.e., Pf （the ratio of pixels that are forested to the total non-water pixels in the window） and P~ （the proportion of all adjacent （cardinal directions only） pixel pairs that include at least one forest pixel, for which both pixels are forested）. Results： Uttara Kannada District has the distinction of having the highest forest cover in Karnataka State, India. this region has been experiencing changes in its forest cover and consequent alterations in functional abilities of its ecosystem. temporal land use analyses show the trend of deforestation, evident from the reduction of evergreen - semi evergreen forest cover from 57.31% （1979） to 32.08 % （2013） Forest fragmentation at the landscape level shows a decline of interior forests 64.42 % （1979） to 25.62 % （20] 3） and transition of non-forest categories such as crop land, plantations and built-up areas, amounting now to 47.29 %. PCA prioritized geophysical and socio variables responsible for changes in the landscape structure at local levels. Conclusion： terrestrial forest ecosystems in Uttara Kannada District of Central Western Ghats have be

关键词： Land use dynamics Forest fraqmentation Interior forests Biodiversity Geophysical variables

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A Convolutional Neural Network Classifier vGG-19 Architecture for Lesion Detection and Grading in Diabetic Retinopathy Based on Deep Learning

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Computers, materials & Continua 2021年第1期66卷 827-842页

作者： v.Sudha t.R.Ganeshbabu Department of Electronics and Communication Engineering Pavai College of TechnologyNamakkal637018India Department of Electronics and Communication Engineering Muthayammal Engineering CollegeRasipuram637408India

Diabetic Retinopathy(DR)is a type of disease in eyes as a result of a diabetic condition that ends up damaging the retina,leading to blindness or loss of *** and physiological retinal variations involving slowdown of blood flow in the retina,elevation of leukocyte cohesion,basement membrane dystrophy,and decline of pericyte cells,*** DR in its initial stage has no symptoms,early detection and automated diagnosis can prevent further visual *** this research,using a Deep Neural Network(DNN),segmentation methods are proposed to detect the retinal defects such as exudates,hemorrhages,microaneurysms from digital fundus images and then the conditions are classified accurately to identify the grades as mild,moderate,severe,no PDR,PDR in ***,saliency detection is applied on color images to detect maximum salient foreground objects from the ***,structure tensor is applied powerfully to enhance the local patterns of edge elements and intensity changes that occur on edges of the ***,active contours approximation is performed using gradient descent to segment the lesions from the ***,the output images from the proposed segmentation process are subjected to evaluate the ratio between the total contour area and the total true contour arc length to label the classes as mild,moderate,severe,No PDR and *** on the computed ratio obtained from segmented images,the severity levels were ***,statistical parameters like the mean and the standard deviation of pixel intensities,mean of hue,saturation and deviation clustering,are estimated through K-means,which are computed as features from the output images of the proposed segmentation *** these derived feature sets as input to the classifier,the classification of DR was ***,a vGG-19 deep neural network was trained and tested using the derived feature sets from the KAGGLE fundus image dataset containing 35,126 images in

关键词： Diabetic retinopathy saliency map structure tensor gradient descent method exudates haemorrhages microaneurysms vGG-19

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Algebraic treatment of the mIC-Kepler System in Spherical Coordinates

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Chinese Physics Letters 2007年第8期24卷 2173-2176页

作者： m. t. Chefrour Departement de Physique Institut des Sciences Centre Universitaire de Souk-Ahras Souk-Ahras Algerie

the mIC-Kepler system is studied via the milshtein Strakhovenko variant of the so（2,1） Lie algebra. Green＇s function is constructed in spherical coordinates, with the help of the Kustaanheimo Stiefel variables and the generators of the S0（2,1） group. the energy spectrum and the normalized wavefunctions of the bound states are obtained.

关键词： FIELD

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Object-Based method Outperforms Per-Pixel method for Land Cover Classification in a Protected Area of the Brazilian Atlantic Rainforest Region

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Pedosphere 2013年第3期23卷 290-297页

作者： t.RIttL m.COOPER R.J.HECK m.v.R.BALLEStER Department of Soil Quality University of Wageningen Department of Soil Science University of So Paulo School of Environmental Sciences University of Guelph Center for Nuclear Energy in Agriculture (CENA) University of So Paulo

Conventional image classification based on pixels hinders the possibilities to obtain information contained in images, while modern object-based classification methods increase the acquisition of information about the object and the context in which it is inserted in the image. the objective of this study was to investigate the performance of different classification methods for land cover mapping in the vicinity of the Alto Ribeira tourist State Park, a Brazilian Atlantic rainforest area. two classification methods were tested, including i） a hybrid per-pixel classification using the image processing software ERDAS Imagine version 9.1 and ii） an object-based classification using the software eCognition version 5. In the first method, six different classes were established, while in the second method, another two classes were established in addition to the six classes in the first method. Accuracy assessment of the classification results presented showed that the object-based classification with a Kappa index value of 0.8687 outperformed the per-pixel classification with a Kappa index value of 0.2224. Application of the user＇s knowledge during the object-based classification process achieved the desired quality; therefore, the use of inter-relationships between objects, superelasses, subclasses, and neighboring classes were critical to improving the efficiency of land cover classification.

关键词： accuracy assessment image classification Kappa index user's knowledge

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to deformation vector special solution in mining subsidence and ground and rock movements

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中国有色金属学会会刊：英文版 2005年第S1期15卷 294-298页

作者： v. Sedlák P. Blit'an technical University of Koice Faculty of Mining Ecology Process Control & Geotechnologies Institute of Geodesy & GIS Park Komenského 19 SK-04384 Koice SlovakiaTechnical University of Koice Faculty of Mining Ecology Process Control & Geotechnologies Institute of Geodesy & GIS Park Komenského 19 SK-04384 Koice Slovakia

the paper presents some specific procedures in modelling a deformation vector at deformation investigation of various engineering structures, buildings or terrain surfaces which are exposed by abiotik factors, for example by underground mining activities or recent geotectonic movements. A specific problem in deformation measurements is solved, when the same conditions of a monitoring network structure cannot be kept during all periodic observations.

关键词： deformation vector mathematical modelling geodetic periodic monitoring

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