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Design of efficient Pt-based electrocatalysts through characterization by X-ray absorption spectroscopy

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Frontiers in Energy 2017年第3期11卷 236-244页

作者： Nebojsa S. MARINKOVIC Kotaro SASAKI radoslav R. ADZIC Synchrotron Catalysis Consortium and Columbia University NY 10027 USA Brookhaven National Laboratory Upton NY 11973 USA

A method is described to determine the internal structure of electrocatalyst nanoparticles by in situ X-ray absorption spectroscopy （XAS）. The nondestructive spec- troscopic technique typically utilizing synchrotron radiation as the source measures changes in the X-ray absorption coefficient as a function of energy. The bulk technique has found its use for materials characterization in all scientific areas, including nanomaterials. The analysis of the internal structure of nanoparticles reveals intera- tomic distances and coordination numbers for each element, and their values and mutual relations indicate whether the elements form a homogeneous or hetero- geneous mixture. The core-shell heterogeneous structure in which certain elements are predominantly located in the core, and others form the encapsulating shell is of particular importance in catalysis and electrocatalysis because it may reduce the amount of precious metals in nanoparticles by replacing the atoms in the core of nanoparticles with more abundant and cheaper alternatives. The examples of nanoparticle structures designed in the laboratory and the approach to model efficient catalysts through systematic analysis of XAS data in electrochemical systems consisting of two and three metals are also demonstrated.

关键词： X-ray absorption spectroscopy EXAFS XANES nanocatalysts core shell

Normalized evaluation of the performance,capacity and availability of catalogue services:a pilot study based on INfrastruture for SPatial InfoRmation in Europe

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International Journal of Digital Earth 2016年第4期9卷 325-341页

作者： Tomáš Řezníka radoslav Chudý Eva Mičietová Department of Geography Masaryk UniversityBrnoThe Czech Republic Department of Cartography Geoinformatics and Remote SensingComenius UniversityBratislavaThe Slovak Republic

Geographic information has a great potential to be re-used when supported by mechanisms for its *** all,the quality of a catalogue service is the key feature supporting users in the discovery *** far,there have been in existence various methodologies dealing with the normalized evaluation of quality with respect to catalogue *** biggest weakness seems to be in the depth of quality testing,*** influences are beyond the scope of evaluation of these methodologies with respect to quality in catalogue *** this study,the quality of 45 catalogue services across Europe was verified with the proposed normalized evaluation methodology originating from documents within the INfrastruture for SPatial InfoRmation in Europe(INSPIRE)*** paper discusses the(statistical)influence of factors that may significantly change the results of catalogue service *** proposals for improving the existing INSPIRE normalized evaluation procedure are applicable for any spatial data infrastructure and/or Digital Earth component using the Open Geospatial Consortium Catalogue Service for the Web as a basis.

关键词： metadata quality evaluation spatial data infrastructures INSPIRE Catalogue Service for the Web

Clinical outcome in patients with hilar malignant strictures type Ⅱ Bismuth-Corlette treated by minimally invasive unilateral versus bilateral endoscopic biliary drainage

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Hepatobiliary & Pancreatic Diseases International 2012年第2期11卷 209-214页

作者： Milutin Bulajic Nikola Panic Miodrag Radunovic Radisav Scepanovic radoslav Perunovic Predrag Stevanovic Tatjana Ille Maurizio Zilli Mirko Bulajic Faculty of Medicine University of BelgradeDr Subotica 811000 BelgradeSerbia University Clinical-Hospital Center "Dragisa MisovicDedinje" Milana Tepica 111000 BelgradeSerbia General Hospital "Danilo I-Cetinje" Vuka Micunovica b.b81250 CetinjeMontenegro Department of Surgery Medical Faculty of PodgoricaUniversity of PodgoricaKrusevac b.b81000 PodgoricaMontenegro Department of Gastroenterology University Clinical Hospital "Santa Maria della Misericordia di Udine"Piazzale S.Maria della Misericorida 1533100 UdineItaly

BACKGROUND:Stenting of malignant hilar strictures remains a standard endoscopic treatment in patients with unresectable *** aim of this two-center prospective study was to compare unilateral versus bilateral drainage in hilar malignant stenosis Bismuth-Corlette type ***:During a 3-year period,a total of 49 patients with hilar tumors(Bismuth-Corlette type II) were referred for endoscopic treatment,following the criteria of ***,computed tomography scan and magnetic resonance cholangiopancreatography(MRCP) were previously performed in all patients in order to facilitate endoscopic retrograde cholangiopancreatography(ERCP).The stricture was first passed by the hydrophilic guide-wire and then contrast medium was *** bile duct dilation was performed,followed by plastic stent placement only in the liver lobe which was previously *** procedures were performed under conscious *** patients were followed up for the next 12 months with a stent exchange every 3 *** outcome was assessed by patient survival in the first 12 months after the ***:All 49 patients were treated with ERCP while 39(79.59%) had successful stent *** these,32 had hilar cholangiocarcinoma(82%) and 7(18%) had gallbladder *** groups of patients had Bismuth II strictures:A,21 patients(54%) with unilateral contrast injection and drainage,and B,18(46%) with bilateral contrast injection and drainage.A total of 57 plastic stents were used(10 Fr,89%;11.5 Fr,11%).Group B showed a lower bilirubin level 7 days after the procedure(P=0.008).Early complications were cholangitis(3 patients,2 in group A and 1 in group B) and acute pancreatitis(2 patients,1 each in A and B) with no statistical difference between the *** complications were stent migration(5 patients,1 in A and 4 in B) and stent clogging(6 patients,2 in A and 4 in B) showing a significant difference between the groups(P<0.01).The first ste

关键词： endoscopic retrograde cholangiopancreatography biliary tree stenosis stenting

Structure-based Comparative Analysis and Prediction of N-linked Glycosylation Sites in Evolutionarily Distant Eukaryotes

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Genomics, Proteomics & Bioinformatics 2013年第2期11卷 96-104页

作者： Phuc Vinh Nguyen Lam radoslav Goldman Konstantinos Karagiannis Tejas Narsule Vahan Simonyan Valerii Soika Raja Mazumder Life Sciences Department Paris Diderot University Department of Biochemistry and Molecular Biology George Washington University Medical Center Department of Oncology Georgetown University Center for Biologics Evaluation and Research Food and Drug Administration

The asparagine-X-serine/threonine （NXS/T） motif, where X is any amino acid except proline, is the consensus motif for N-linked glycosylation. Significant numbers of high-resolution crystal structures of glycosylated proteins allow us to carry out structural analysis of the N-linked glycosylation sites （NGS）. Our analysis shows that there is enough structural information from diverse glycoproteins to allow the development of rules which can be used to predict NGS. A Python-based tool was developed to investigate asparagines implicated in N-glycosylation in five species： Homo sapiens, Mus musculus, Drosophila melanogaster, Arabidopsis thaliana and Saccharo- myees cerevisiae. Our analysis shows that 78 % of all asparagines of NXS/T motif involved in N-gly- cosylation are localized in the loop/turn conformation in the human proteome. Similar distribution was revealed for all the other species examined. Comparative analysis of the occurrence of NXS/T motifs not known to be glycosylated and their reverse sequence （S/TXN） shows a similar distribu- tion across the secondary structural elements, indicating that the NXS/T motif in itself is not bio- logically relevant. Based on our analysis, we have defined rules to determine NGS. Using machine learning methods based on these rules we can predict with 93% accuracy if a particular site will be glycosylated. If structural information is not available the tool uses structural prediction results resulting in 74% accuracy. The tool was used to identify glycosylation sites in 108 human proteins with structures and 2247 proteins without structures that have acquired NXS/T site/s due to non-synonymous variation. The tool, Structure Feature Analysis Tool （SFAT）, is freely available to the public at http：//***/tools/sfat.

关键词： N-linked glycosylation Gain and loss of glycosyla-tion nsSNP nsSNV Variation

Exopolysaccharides from Lactic acid Bacteria as Corrosion Inhibitors

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Journal of Life Sciences 2014年第12期8卷 940-945页

作者： Ignatova-Ivanova Tsveteslava radoslav Ivanov Department of Biology University of Shumen Shumen 9712 Bulgaria

Bacterial EPSs （exopolysaccharides） are believed to play an important role in the environment by promoting survival strategies such as bacterial attachment to surfaces and nutrient trapping, which facilitate processes of biofilm formation and development. These microbial biofilms have been implicated in corrosion of metals, bacterial attachment to prosthetic devices, fouling of heat exchange surfaces, toxicant immobilization, and fouling of ship hulls. In this paper, data on EPS production and the effect of EPS on corrosion of steel produced by Lactobacillus fermentum Ts are presented and discussed. The Lactobacillus fermentum Ts strain was isolated from types of Bulgarian rye flour. It was tested for its ability to produce exopolysaccharides when cultivated in a media containing 10% sucrose, 10% fructose and 10% maltose. The study of the corrosive stability of steel samples was conducted on the gravimetrique method. The rate of corrosion, the degree of protection, and coefficient of protection have been calculated. The structure of layer over steel plates was analysed by SEM （scanning electron microscopy） JSM 5510. It could be underlined that 10% sucrose and 10% maltose in the media stimulated the process of protection of corrosion.

关键词： Corrosion inhibitor lactic acid bacteria SEM

Study of Biofilm Formed by Lactic Acid Bacteria on the Surface of Mild Steel

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Journal of Life Sciences 2014年第10期8卷 799-804页

作者： Tsveteslava Veselinova Ignatova-Ivanova radoslav Iliev Ivanov Department of Biology University of Shumen Shumen 9712 Bulgaria

Biocorrosion processes at metal surfaces are associated with microorganisms, or the products of their metabolic activities including enzymes, exopolymers, organic and inorganic acids, as well as volatile compounds such as ammonia or hydrogen sulfde. It was proved that strain Lactobacillus delbrueckii B5 constituted biofilms in the presence of different amounts of carbohydrates （5% sucrose and a mixture of 5% lactose, 5% fructose and 5% maltose）. The obtained information was used in a study treating the anticorrosive properties of microbial biofilms synthesized by the latter strain. The study of the corrosive stability of steel samples was conducted on the gravimetrique method. The rate of corrosion, calculated. The structure of layer over steel plates was analyzed by the degree of protection, and coefficient of protection has been Scanning Electron Microscopy （SEM） JSM 5510.

关键词： Biofilm corrosion inhibitor lactic acid bacteria SEM.

Computer Aided Design of Grinding Wheel for Drill Flute Production

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Journal of Mechanics Engineering and Automation 2014年第9期4卷 709-715页

作者： Janko Jovanovic Obrad Spaic radoslav Tomovic Rade Ivankovic Faculty of Mechanical Engineering University of Montenegro Podgorica 81000 Montenegro Production and Management Faculty East Sarajevo University Trebinje 89101 Republika Srpska

Twist drill flute profile design is necessary in order to determine the required grinding wheel profile for a flute production. An accurate drill flute profile design is generated for two-flute conical twist drills using analytical equations to generate a drill flute profile design needed for the production of twist drills with straight lips. The required grinding wheel profile for a flute production was expressed in digitized form as well as in terms of two curve-fitted circular arcs. The drill flute profile geometry can never be precisely generated when required grinding wheel profile is represented by two circular arcs and the generated flute profile is just a very good approximation of the design flute profile. A CAD （computer aided design） software has been developed using MATLAB to determine the required grinding wheel profile for generating a given drill flute profile design.

关键词： Grinding wheel profile drill flute profile twist drill CAD.

THE EFFECT OF AZITROMYCIN ON SOME ANTIOXIDANT SYSTEMS IN ANIMALS WITH ULCERI STRESS

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THE EFFECT OF AZITROMYCIN ON SOME ANTIOXIDANT SYSTEMS IN ANI...

Hydrogen Oxidation Reaction on different Pt core-shell catalysts in Alkaline Electrolyte

第十五届国际药理学大会

作者： Hudomal Snezana Rasic Julijana Popovic Mira Kaurinovic Biljana Mitic radoslav Instutute of Pharmacology. SCG. Instutute of Pharmacology. SCG. Department of Chemistry.SCG. Department of Chemistry.SCG. Instutute of Pharmacology. SCG.

＜正＞ Azitromycin was applied daily orally. 5 days before stress, and the animals were sacrified 1 hour after oral administrated ImL absolute ethanol. under the ether anesthesia. Antioxidative parameters （the value of reduced glutatione - GSH and the activity of glutatione paroxidase - GSHPx. glutatione reductase - GSHR. and peroxidase） were determined in liver homogenate. The quntity of GSH was lower in stressed animals, and olso was lower （p ＜ 0. 001） in animals treated by azitromycin either control and stressed animals. The activity of GSHPx was very reduced in stressed animals comparing to the control, and lower in azitromycintreated animals（p ＜ 0.001） comparing to the control and higher than in stressed animals （p＜0.001）.The activity of GSHR was not statistically diferent in each of compared group. The activity of Px was statistically higher in stressed animals comparing to the control, and olso higher in animals treated by azitromycin either in control （p ＜ 0.01） and stressed animals （p ＜ 0. 001）. Azitromicin protected gastric mucosa against ethanol damage, but reduced glutatione and increased peroxidase activity in the liver of stress - ulcer rats.

关键词： stress - ulcer azitromycin. enzyme liver.

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Hydrogen Oxidation Reaction on different Pt core-shell catal...