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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

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Microwave photonics

Science China(Information Sciences) 2022年第12期65卷 49-112页

作者： Jianping YAO jose CAPMANY Microwave Photonics Research Laboratory School of Electrical Engineering and Computer Science University of Ottawa ITEAM Research Institute Universitat Politècnica de València iPronics Programmable Photonics

Microwave photonics, an interdisciplinary field that combines microwave engineering and photonic technology for the generation, transmission, processing, and control of microwave signals, to take advantage of the broad bandwidth, high frequency, and low loss offered by modern photonics, has been intensively researched for the last few decades, and numerous solutions have been proposed and demonstrated. In this article, an overview about microwave photonics is provided which covers the basic concepts of microwave photonics, photonic-assisted microwave signal generation, photonic-assisted microwave signal processing, and true time delay beamforming. The implementation of microwave photonic systems based on photonic integrated circuits is also reviewed, including the design, fabrication, and material platforms, application-specific photonic integrated circuits for microwave photonics, and programmable integrated microwave *** challenges and future applications of microwave photonics are also discussed.

关键词： microwave photonics photonic integrated circuits microwave photonic link microwave photonic signal processor optoelectronic oscillator radio over fiber

Acute hepatitis with autoimmune features after COVID-19 vaccine:coincidence or vaccine-induced phenomenon?

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Gastroenterology Report 2022年第1期10卷 628-631页

作者： jose M.Pinazo-Bandera Alicia.hernandez-Albujar Ana Isabel Garcia-Salguero Isabel Arranz-Salas Raul J.Andrade Mercedes Robles-Diaz Division of Gastroenterology and Hepatology Instituto de Investigacion Biomedica de Malaga-IBIMAHospital Universitario Virgen de la VictoriaUniversidad de MalagaMalagaSpain Division of Anatomical Pathology Hospital Universitario Virgen de la VictoriaMalagaSpain Centro de Investigacion Biomedica en Red de Enfermedades Hepaticas y Digestivas(CIBERehd) MadridSpain

Introduction Autoimmune diseases result from a breach of immunological self-tolerance and tissue damage by autoreactive T *** acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is characterized by an inflam... 详细信息

关键词： autoimmune vaccine acute

Design optimization of multilayer perceptron neural network by ant colony optimization applied to engine emissions data

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Science China(Technological Sciences) 2019年第6期62卷 1055-1064页

作者： MARTINEZ-MORALES jose QUEJ-COSGAYA Hector LAGUNAS-JIMENEZ jose PALACIOS-hernandez Elvia MORALES-SALDANA Jorge Faculty of Engineering Autonomous University of Campeche Campeche 24039 Mexico Faculty of Sciences Autonomous University of San Luis Potosi San Luis Potosi 78290 Mexico Faculty of Engineering Autonomous University of San Luis Potosi San Luis Potosi 78290 Mexico

A multilayer perceptron(MLP) artificial neural network(ANN) model has been optimized by the multi-objective ant colony optimization(MOACO) algorithm, which uses three objective functions. A sensitivity analysis to choose MOACO parameter values is carried out by calculating hypervolume metric, and the proposed approach adopts the Vlsekriterijumska Optimizacija I Kompromisno Resenje(VIKOR) decision method to choose final compromised solution on the Pareto front obtained from MOACO. As a result, we used the MLP-MOACO developed model to estimate the value of engine emissions of NOxin a four stroke, spark ignition(SI) gasoline engine and observed acceptable correlation coefficient(R^2) of 0.99978.

关键词： ant colony optimization multilayer perceptron artificial neural networks hypervolume engine emissions

Habitat-dependent breeding biology of the Blue Tit(Cyanistes caeruleus)across a continuous and heterogeneous Mediterranean woodland

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Avian Research 2023年第3期14卷 499-510页

作者： Jorge Garrido-Bautista Carmen hernandez-Ruiz jose Luis Ros-Santaella Eliana Pintus Nicola Bernardo Mar Comas Gregorio Moreno-Rueda Department of Zoology Faculty of SciencesUniversity of Granada18071GranadaSpain Tecnologías y Servicios Agrarios S.A. S.M.E.M.P.(Tragsatec)06800BadajozSpain Department of Veterinary Sciences Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences PragueKamýcka 12916500Prague 6-SuchdolCzech Republic Biological Station of Donana EBD-CSICAv.Americo Vespucio 2641092SevilleSpain Department of Biological Sciences Dartmouth College03755HanoverNHUSA

Mediterranean woodland environments are characterised by high spatial and temporal heterogeneity,which means the inhabiting species face a wide variety of selective *** may respond differently to habitat heterogeneity and so distinct eco-evolutionary scenarios may be responsible for the inter-habitat variability in reproductive strategies observed in certain *** inter-forest variability of some reproductive traits in passerines has been examined by comparing forest patches or separated ***,there is still little information regarding how such highly mobile animals adjust their breeding performance across continuous and heterogeneous *** we studied the reproductive performance of a population of Blue Tits(Cyanistes caeruleus) in an area of continuous Mediterranean woodland that included two mountain slopes and four different types of forest,ranging from deciduous oak forests to perennial non-oak *** studied the habitat heterogeneity and inter-forest phenotypic variation in terms of reproductive performance and adult and nestling biometry,besides also exploring the effects of ectoparasites on Blue Tit *** were laid earliest in deciduous Pyrenean Oak(Quercus pyrenaica) forests,while clutch size and the number of fledglings were highest in the humid Pyrenean Oak forest,which had the greatest tree coverage and most humid climate,and lowest in the coniferous Scots Pine(Pinus sylvestris) *** were no inter-forest differences in hatching(percentage of nests with at least one egg hatched) and fledging(percentage of nests in which at least one nestling fledged)***,there were no inter-forest differences in adult and nestling biometry,but adults that raised more fledglings had a lower body mass,while males whose females laid larger clutches had smaller *** ectoparasites did not affect Blue Tit reproduction,although Culicoides had a negative impact on nestling body *** results

关键词： Birds Breeding success Cavity-nesting birds Paridae Passerines Reproduction

Journal of the American Heart Association|肝硬化退伍军人心肺血流动力学与病死率的关系:一项回顾性队列研究

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临床肝胆病杂志 2024年第6期40卷 1254-1254页

作者：杜佳霖温晓玉吉林大学第一医院肝胆胰内科

门脉性肺动脉高压(PoPH)与患者病死率增加相关,可能会限制肝脏疾病的治疗选择。目前缺乏与PoPH心肺血流动力学相关的临床风险连续性的数据。2024年4月,美国辛辛那提大学医学系jose等探讨了肝硬化退伍军人心肺血流动力学与死亡率的关系。

关键词：肺血流动力学回顾性队列研究医学系门脉性肺动脉高压临床风险辛辛那提大学肝硬化病死率

A New Phasor Estimator for PMU Applications:P Class and M Class

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 55-66页

作者： jose R.Razo-hernandez Arturo Mejia-Barron David Granados-Lieberman Martin Valtierra-Rodriguez jose F.Gomez-Aguilar ENAP-Research Group Facultad de IngenieríaUniversidad Autónoma de Querétaro(UAQ)San CayetanoC.P.76807México ENAP-Research Group Departamento de Ingeniería ElectromecánicaInstituto Tecnológico Superior de Irapuato(ITESI)Colonia El CopalC.P.36821México CONACyT-Centro Nacional de Investigación y Desarrollo Tecnológico(CENIDET) Tecnológico Nacional de MéxicoInterior Internado Palmira S/NCol.PalmiraC.P.62490México

Phasor measurement units(PMUs)are fundamental tools in the applications of modern power systems,where synchronized phasor estimations are *** accuracy and dynamic performance requirements for phasor,frequency,and rate of change of frequency(ROCOF)estimations are established in the IEEE Std.C37.118.1-2011 along with the IEEE Std.C37.118.1 a-2014,where two PMU performances are suggested:P class filters for applications requiring fast response and M class filters for applications requiring high rejection to aliased *** this paper,a methodology to design new phasor estimators that satisfy the P class and M class requirements in PMUs is *** proposed methodology is based on finite impulse response filters,brick-wall filters,and complex filter design concepts,where frequency range,time performance,harmonic rejection and out-of-band interference requirements are considered in its design.A comparative analysis using the reference model given by the IEEE Std.C37.118.1 is *** results show the effectiveness of the phasor estimators under steady-state and dynamic conditions according to the PMU standard,making them suitable tools for applications in power systems.

关键词： Brick-wall filter complex filter IEEE Std.C37.118.1 M class P class phasor measurement unit(PMU) phasor estimator

Burden of bone disease in chronic pancreatitis:A systematic review and meta-analysis

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World Journal of Gastroenterology 2023年第8期29卷 1374-1394页

作者： Ankit Chhoda Maria jose hernandez-Woodbine Nana Afua Akkya Addo Syed Alishan Nasir Alyssa Grimshaw Craig Gunderson Awais Ahmed Steven D.Freedman Sunil G.Sheth Department of Gastroenterology Beth Israel Deaconess Medical CenterBostonMA 02215United States Department of Medicine Norwalk HospitalYale School of MedicineNorwalkCT 06850United States Cushing/Whitney Medical Library Yale UniversityNew HavenCT 06510United States General Internal Medicine Yale School of MedicineNew HavenCT 06510United States

BACKGROUND Bone disease is an under-recognized cause of morbidity in chronic pancreatitis(CP).Over the past decade,publications of original studies on bone disease in CP has warranted synthesis of the evidence to ascertain the true burden of the *** To quantify the prevalence of osteopenia,osteoporosis,and fragility fractures in CP patients and investigate the associated clinical features and *** A systematic search identified studies investigating bone disease in CP patients from Cochrane Library,Embase,Google Scholar,Ovid Medline,PubMed,Scopus,and Web of Science,from inception until October *** outcomes included prevalence of osteopenia,osteoporosis,and fragility fractures,which were metaanalyzed using a random-effects model and underwent metaregression to delineate association with baseline clinical *** Twenty-one studies were included for systematic review and 18 studies were included for *** pooled prevalence of osteopenia and osteoporosis in CP patients was 41.2%(95%CI:35.2%-47.3%)and 20.9%(95%CI:14.9%-27.6%),*** pooled prevalence of fragility fractures described among CP was 5.9%(95%CI:3.9%-8.4%).Metaregression revealed significant association of pancreatic enzyme replacement therapy(PERT)use with prevalence of osteoporosis[coefficient:1.7(95%CI:0.6-2.8);P<0.0001].We observed no associations with mean age,sex distribution,body mass index,alcohol or smoking exposure,diabetes with prevalence of osteopenia,osteoporosis or fragility *** of data on systemic inflammation,CP severity,and bone mineralization parameters precluded a formal *** This meta-analysis confirms significant bone disease in patients with *** than PERT use,we observed no patient or study-specific factor to be significantly associated with CP-related bone *** studies are needed to identify confounders,at-risk population,and to understand the mechanisms of CP-related bone disease an

关键词： Chronic pancreatitis Fractures Osteoporosis Osteopenia Bone disease

Nestling sex ratio is unaffected by individual and population traits in the griffon vulture

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Current Zoology 2023年第3期69卷 227-235页

作者： Guillermo Gomez-Lopez Felix Martinez Ana Sanz-Aguilar Martina Carrete Guillermo blanco Department of Evolutionary Ecology National Museum of Natural Sciences(MNCN)Spanish National Research Council(CSiC)Jose Gutierrez Abascal 228006 MadridSpain Escuela Internacional de Doctorado Universidad Rey Juan Carlos(URJC)Tulipan s/n28933 MostolesMadridSpain Animal Demography and Ecology Group Institut Mediterrani d'Estudis Avangats(IMEDEA)Miquel Marques 217020 EsporlesMallorcaSpain Applied Zoology and Conservation Group Universitat de les Illes Balears(UIB)Ctra.De Valldemossa km.7.507122PalmaSpain Department of Physical Chemical and Natural SystemsUniversidad Pablo de Olavide(UPO)Ctra.de Utrera km.141013 SevillaSpain

Variation in offspring sex ratios is a central topic in animal demography and population *** studies have focused on bird species with marked sexual dimorphism and multiple-nestling broods,where the offspring sex ratio is often biased due to different individual or environmental ***,biases in offspring sex ratios have been far less investigated in monomorphic and single-egg laying species,and few studies have evaluated long-term and large-scale variations in the sex ratio of nestling ***,we explore individual and environmental factors potentially affecting the secondary sex ratio of the monomorphic griffon vulture Gyps *** used information collected at three breeding nuclei from central Spain over a 30-year period(1990–2020)to analyse the effects of nestling age,parental age,breeding phenology,conspecific density,population reproductive parameters,and spatial and temporal variability on nestling *** ratio did not differ from parity either at the population or the nuclei *** significant between-year differences were detected,even under highly changing conditions of food availability associated with the mad-cow *** found that tree nesting breeders tend to have more sons than daughters,but as this nesting behavior is rare and we consequently have a small sample size,this issue would require additional *** further research is needed to assess the potential effect of breeder identity on nestling sex ratio,this study contributes to understanding the basic ecology and population dynamics of Griffon Vultures,a long-lived species with deferred maturity and low fecundity,whose minor deviations in the offspring sex ratio might imply major changes at the population level.

关键词： offspring sex ratio nestling sex Gyps fulvus monomorphism mad-cow crisis demography