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On a Classical Theorem on the Diameter and Minimum Degree of a Graph

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Acta Mathematica Sinica,English Series 2017年第11期33卷 1477-1503页

作者： veronica HERNANDEZ Domingo PESTANA Jose M. RODRIGUEZ Universidad CarlosⅢde Madrid Avenida de la Universidad3028911 LeganesSpain

In this work, we obtain good upper bounds for the diameter of any graph in terms of its minimum degree and its order, improving a classical theorem due to Erdos, Pach, Pollack and Tuza. We use these bounds in order to study hyperbolic graphs （in the Gromov sense）. To compute the hyperbolicity constant is an almost intractable problem, thus it is natural to try to bound it in terms of some parameters of the graph. Let H（n, δ0） be the set of graphs G with n vertices and minimum degree 50, and J（n, Δ） be the set of graphs G with n vertices and maximum degree A. We study the four following extremal problems on graphs： a（n,δ0） = min{δ（G）｜ G ∈H（n, δ0）}, b（n, δ0） =- max{δ（G）｜ e ∈H（n, δ0）}, α（n, Δ） = min{δ（G） [ G ∈ J（n, Δ）} and β（n,Δ） = max{δ（G） ] G∈Π（n,Δ）}. In particular, we obtain bounds for b（n, δ0） and we compute the precise value of a（n, δ0）, α（n, Δ） and w（n, Δ） for all values of n, r0 and A, respectively.

关键词： Extremal problems on graphs diameter minimum degree maximum degree Gromov hyperbolicity hyperbolicity constant finite graphs

Nanosized magnetite in low cost materials for remediation of water polluted with toxic metals, azo- and antraquinonic dyes

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 746-769页

作者： Maria Fernanda HORST veronica LASSALLE Maria Lujan FERREIRA Institute of Chemistry of the South (Inquisur Universidad Nacional del Sur~ONICET) Avda Alem 1253 Bahia Blanca Argentina Pilot Plant of Chemical Engineering (PLAPIQUI-UNS-CONICET) Universidad Nacional del Sur--CONICET Camino La Carrindanga km7 Bahia Blanca Argentina

Nanosized magnetite has emerged as an adsorbent of pollutants in water remediation. Nanoadsor- bents include magnetic iron oxide and its modifiers/ stabilizers, such as carbon, silica, clay, organic moieties （polymers, aminoaeids, and fatty acids） and other inorganic oxides. This review is focused on the recent developments on the synthesis and use of magnetic nanoparticles and nanocomposites in the treatment of contaminated water. The emphasis is on the influence of the iron oxide modifiers on some properties of interest such as size, BET area, and magnetization. The characteristics of these nanomaterials are related to their ability to eliminate heavy metal ions and dyes from wastewater. Comparative analysis of the actual literature was performed aiming to present the magnetic material, its preparation methodology and performance in the elimination of the selected pollutants. Vast information has been properly summarized according to the materials, their properties and preferential affinity for selected contaminants. The mechanisms governing nanomaterial＇s formation as well as the interactions with heavy metals and dyes have been carefully analyzed and associated to their efficiency.

关键词： nanomagnetite water remediation toxicmetals dyes supported magnetite

Landing in Ski Jumping: A Review About its Biomechanics and the Connected Injuries

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Journal of Science in Sport and Exercise 2021年第3期3卷 238-248页

作者： veronica Bessone Ansgar Schwirtz Department of Biomechanics in Sports Faculty of Sport and Health SciencesTechnical University of MunichMunichBavariaGermany

The present review deals with the current scientific knowledge related with ski jump landing.A specific focus is given on the landing biomechanics,the methods utilized for its analysis and the injuries connected to the landing *** the demonstrated importance for the safety and the performance of ski jumpers,the landing and its preparation are rarely *** this paper,after having firstly described the execution of landing and its preparation and the reason why is impor-tant to analyze it,an overview of the current status of the research related to the landing biomechanics is reported(kinetics,kinematics,electromyographic activation,aerodynamics,computer simulation).The third part describes the methods and technologies utilized in literature to analyze the landing and its preparation(video cameras,inertial sensors,force insoles,wind tunnel and computer simulation).After that,an overview of the injuries related to landing is *** final section proposes future research in the field of biomechanics of ski jump landing in different fields,such as computer simulations,kinematic analysis,equipment development and biomechanics of female athletes.

关键词： Feedback Sensors Prevention Kinetics Kinematics Winter sports

Role of dup A in virulence of Helicobacter pylori

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World Journal of Gastroenterology 2016年第46期22卷 10118-10123页

作者： Amin Talebi Bezmin Abadi Guillermo perez-perez Department of Bacteriology Faculty of Medical Sciences Tarbiat Modares University Departments of Medicine and Microbiology New York University School of Medicine and VA Medical Center

Helicobacter pylori(H. pylori) is a gastric human pathogen associated with acute and chronic gastritis, 70% of all gastric ulcers, 85% of all duodenal ulcers, and both forms of stomach cancer, mucosal-associated lymphoid tissue(MALT) lymphoma and adenocarcinoma. Recently, attention has focused on possible relationship between presence of certain virulence factor and H. pylori-associated diseases. Some contradictory data between this bacterium and related disorders has been observed since not all the colonized individuals develop to severe disease. The reported diseases plausibility related to H. pylori specific virulence factors became an interesting story about this organism. Although a number of putative virulence factors have been identified including cytotoxin-associated gene a(cag A) and vac A, there are conflicting data about their actual participation as specific risk factor for H. pylori-related diseases. Duodenal ulcer promoting gene a(dup A) is a virulence factor of H. pylori that is highly associated with duodenal ulcer development and reduced risk of gastric cancer. The prevalence of dup A in H. pylori strains isolated from western countries is relatively higher than in H. pylori strains from Asian countries. Current confusing epidemiological reports will continue unless future sophisticated and molecular studies provide data on functional and complete dup A cluster in H. pylori infected individuals. This paper elucidates available knowledge concerning role of dup A in virulence of H. pylori after a decade of its discovery.

关键词： Helicobacter pylori dup A Bacterial virulence infection Clinical outcome

Tissue inhibitors of metalloproteases strike a nerve

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Neural Regeneration Research 2018年第11期13卷 1890-1892页

作者： veronica i.shubayev alex y.strongin department of anesthesiology university of californiasan diego va san diego healthcare system la jollacausa sanford burnham prebys medical discovery institute la jollacausa

Signals of touch,pressure,pain,temperature,position,and vibration are transmitted from the peripheral nervous system（PNS）to the dorsal horn of the segmental spinal cord via pseudounipolar dorsal root ganglia（DRG）*** information gathering relies on functional integrity of DRG neurons and can be interrupted by PNS injury due to trauma,disease or exposure to drugs, toxins or viral pathogens. Despite the high regenerative capacity of DRG neurons, sensory recovery after PNS injury is often incomplete and severe neuropathic pain may last for years. Although numerous mechanisms of PNS injury have been established, neuropathic pain is refractory to therapy, contributing to the physical and emotional suffering of patients and the enormous economic burden to society.

关键词： TIMPs PNS In Tissue inhibitors of metalloproteases strike a nerve

Corneal compensation of presbyopia:PresbyLASIK:an updated review

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Eye and Vision 2017年第1期4卷 48-55页

作者： veronica Vargas-Fragoso Jorge L.Alió Vissum Corporation Edificio VissumCalle Cabañal 1AlicanteSpain Division of Ophthalmology Universidad Miguel HernándezCarretera Alicante-Valencia km 8.7AlicanteSpain.

The main purpose of this review is to compare and analyze the results of the main PresbyLASIK approaches;central and ***:A comprehensive research was conducted in PUBMED using keywords like“presbyopia correction”,“PresbyLASIK”,“Corneal multifocality”,“Laser blended vision”.We reviewed the PresbyLASIK technique,uncorrected distance visual acuity(UDVA),corrected distance visual acuity(CDVA),uncorrected near visual acuity(UNVA),and corrected near visual acuity(CNVA),and compared the differences between the techniques.

关键词： Central and peripheral PresbyLASIK Corneal multifocality Presbyopia

Learning from a carbon dioxide capture system dataset: Application of the piecewise neural network algorithm

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Petroleum 2017年第1期3卷 56-67页

作者： veronica Chan Christine Chan Energy Informatics Laboratory Faculty of Engineering and Applied ScienceUniversity of ReginaReginaSK S4S0A2Canada

This paper presents the application of a neural network rule extraction algorithm,called the piecewise linear artificial neural network or PWL-ANN algorithm,on a carbon capture process system *** objective of the application is to enhance understanding of the intricate relationships among the key process *** algorithm extracts rules in the form of multiple linear regression equations by approximating the sigmoid activation functions of the hidden neurons in an artificial neural network(ANN).The PWL-ANN algorithm overcomes the weaknesses of the statistical regression approach,in which accuracies of the generated predictive models are often not satisfactory,and the opaqueness of the ANN *** results show that the generated PWL-ANN models have accuracies that are as high as the originally trained ANN models of the four datasets of the carbon capture process *** analysis of the extracted rules and the magnitude of the coefficients in the equations revealed that the three most significant parameters of the CO_(2) production rate are the steam flow rate through reboiler,reboiler pressure,and the CO_(2) concentration in the flue gas.

关键词： Carbon dioxide capture process system Artificial neural network Rule extractions Non-linear modeling Linear regression

Diversity of Arbuscular Mycorrhizal Fungi Associated with Six Rice Cultivars in Italian Agricultural Ecosystem Managed with Alternate Wetting and Drying

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Rice science 2023年第4期30卷 348-358,I0028-I0030页

作者： veronica VOLPE Franco MAGURNO Paola BONFANTE Stefano GHIGNONE Erica LUMINI Department of Life Sciences and Systems Biology University of TurinV.le P.A.Mattioli 25I-10125 TurinItaly Institute of Biology Biotechnology and Environmental ProtectionFaculty of Natural SciencesUniversity of Silesia in KatowiceJagiellońska 28Katowice 40-032Poland Institute for Sustainable Plant Protection-Turin Unit National Research Council of ItalyV.le P.A.Mattioli 25I-10125 TurinItaly

Alternate wetting and drying(AWD)system,in which water has been reduced by approximately 35%with an increased occurrence of beneficial arbuscular mycorrhizal(AM)symbiosis and no negative impact on rice yield,was proposed to utilize water and nutrients more *** this study,we selected six rice cultivars(Centauro,Loto,Selenio,Vialone nano,JSendra and Puntal)grown under AWD conditions,and investigated their responsiveness to AM colonization and how they select diverse AM *** order to investigate root-associated AM fungus communities,molecular cloning-Sanger sequencing on small subunit rDNA data were obtained from five out of the six rice cultivars and compared with Next Generation Sequencing(NGS)data,which were previously obtained in Vialone *** results showed that all the cultivars were responsive to AM colonization with the development of AM symbiotic structures,even if with differences in the colonization and arbuscule abundance in the root *** identified 16 virtual taxa(VT)in the soil compartment and 7 VT in the root *** emphasized that the NGS analysis gives additional value to the results thanks to a more in-depth reading of the less represented AM fungus taxa.

关键词： alternate wetting and drying system arbuscular mycorrhizal fungi rice molecular diversity virtual taxa

Failure of levees induced by toe uplift:Investigation of post-failure behavior using material point method

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 970-983页

作者： veronica Girardi Francesca Ceccato Alex Rohe Paolo Simonini Fabio Gabrieli University of Padua Department of CivilEnvironmental and Architectural EngineeringVia Ognissanti 39PaduaItaly GeoHal Graswinckelstraat 50DelftNetherlands

Levees are essential structures in flood defense systems,and their failures can lead to devastating consequences on the surrounding *** of the failure mechanisms mostly controlled by the foundation soil stratigraphy is the instability of the land side slope,triggered by the development of high uplift pressures in the *** complex phenomenon has been investigated experimentally with centrifuge tests or large-scale tests and numerically with the limit equilibrium method(LEM)and the finite element method(FEM).In this work,we applied a multiphase formulation of the material point method(MPM)to analyze the development of toe uplift instability mechanism,from the onset of failure to large *** numerical model is inspired by an experiment carried out in a geotechnical centrifuge test by Allersma and Rohe(2003).The comparison with the experiment allows for understanding critical pore pressure triggering large displacements in the foundation ***,we numerically evaluated the impact of different values of foundation soils’hydraulic conductivity on the failure *** results show that hydraulic conductivity mainly influences the time of failure onset and the extension of shear localization at ***,the advantages of using large displacement approaches in the safety assessment of earth structures are *** FEM,there are no issues with element distortions generating difficulties with numerical convergence,allowing for full postfailure *** capability permits precise quantification of earth structure damages and post-failure *** ensuing reinforcement systems’design is no longer over-conservative,with a significant reduction in associated costs.

关键词： Slopes safety assessment Levees Uplift pressure Large deformation analysis