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Acta Mathematica Sinica,English Series 2007年第9期23卷 1719-1728页

作者： J.CAb.llERO b.lópez K.SADARANGANI Departamento de Matemáticas Universidad de Las Palmas de Gran CanariaCampus de Tafira Baja35017 Las Palmas de Gran CanariaSpain

We use a technique associated with measures of noncompactness to prove the existence of nondecreasing solutions to an integral equation with linear modification of the argument in the space C[0, 1]. In the last thirty years there has been a great deal of work in the field of differential equations with a modified argument. A special class is represented by the differential equation with affine modification of the argument which can be delay differential equations or differential equations with linear modifications of the argument. In this case we study the following integral equation x（t） = a（t）＋（Tx）（t） ∫0^σ（t） u（t, s, x（s）, x（λs））ds 0 〈 λ 〈 1 which can be considered in connection with the following Cauchy problem x＇（t） = u（t, s, x（t）, x（λt））, t ∈ [0, 1], 0 〈 λ 〈 1 x（0） = u0.

关键词： measure of noncompactness fixed point theorem nondecreasing solutions

A solution to the hydrodynamic lubrication of a circular point contact sliding over a flat surface with cavitation

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Theoretical & Applied Mechanics letters 2012年第3期2卷 62-64页

作者： Hans b.lfgren Functional Surfaces Research Group School of Business and EngineeringUniversity of HalmstadP.O.Box 823SE-301 18 HalmstadSweden

This letter presents an analytical solution to the hydrodynamic lubrication of a circular point contact sliding over a flat surface with *** solution is found by solving the Reynolds equation with Reynolds boundary condition for *** cavitation boundary is shown to be straight lines directed 108.4°against the sliding *** result is experimentally verified in the limit of large values of viscosity,sliding velocity and radius of a spherical *** solution raises questions about the coupling between cavitation and film rupture and can be used as an independent check on the validity of numerical solutions.

关键词： Reynolds equation analytical solution cavitation point contact

Effects of thermophoresis particle deposition and of the thermal conductivity in a porous plate with dissipative heat and mass transfer

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Acta Mechanica Sinica 2011年第3期27卷 389-398页

作者： Joaquín Zueco O.Anwar bég l.M.lpez-Ochoa Thermal Engineering and Fluids Department Technical University of CartagenaETSII Campus Muralla del Mar Aerospace Engineering Department of Engineering and MathematicsSheaf BuildingSheffield Hallam University Mechanical Engineering Departament University of RiojaC/Luís de UlloaLogrono (La Rioja)20E-26004Spain

Network simulation method（NSM） is used to solve the laminar heat and mass transfer of an electricallyconducting,heat generating/absorbing fluid past a perforated horizontal surface in the presence of viscous and Joule heating problem. The governing partial differential equations are non-dimensionalized and transformed into a system of nonlinear ordinary differential similarity equations,in a single independent variable,畏. The resulting coupled,nonlinear equations are solved under appropriate transformed boundary conditions. Computations are performed for a wide range of the governing flow parameters,viz Prandtl number,thermophoretic coeffcient（a function of Knudsen number）,thermal conductivity parameter,wall transpiration parameter and Schmidt number. The numerical details are discussed with relevant applications. The present problem finds applications in optical fiber fabrication,aerosol filter precipitators,particle deposition on hydronautical blades,semiconductor wafer design,thermo-electronics and problems including nuclear reactor safety.

关键词： Thermophoresis . MHD . Network simulation model . Heat and mass transfer- Hartmann number

Hepatitis b and inflammatory bowel disease: Role of antiviral prophylaxis

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World Journal of Gastroenterology 2013年第9期19卷 1342-1348页

作者： Pilar lópez-Serrano Jose lázaro Pérez-Calle Maria Dolores Sánchez-Tembleque Department of Gastroenterology University Hospital Fundación Alcorcón 28922 Madrid Spain Department of Gastroenterology University Hospital of Guadalajara 19002 Guadalajara Spain

Hepatitis b virus (HbV) is a very common infection worldwide. Its reactivation in patients receiving immunosuppression has been widely described as being associated with significant morbidity and mortality unless anti-viral prophylaxis is administered. Treatment in inflammatory bowel disease (IbD) patients has changed in recent years and immunosuppression and biological therapies are now used more frequently than before. Although current studies have reported an incidence of hepatitis b in inflammatory bowel disease patients similar to that in the general population, associated liver damage remains an important concern in this setting. liver dysfunction may manifest in several ways, from a sub.le change in serum aminotransferase levels to fulminant liver failure and death. Patients undergoing double immunosuppression are at a higher risk, and reactivation usually occurs after more than one year of treatment. As preventive measures, all IbD patients should be screened for HbV markers at diagnosis and those who are positive for the hepatitis b surface antigen should receive antiviral prophylaxis before undergoing immunosuppression in order to avoid HbV reactivation. Tenofovir/entecavir are preferred to lamivudine as nucleos(t)ide analogues due to their better resistance profile. In patients with occult or resolved HbV, viral reactivation does not appear to be a relevant issue and regular DNA determination is recommended during immunosuppression therapy. Consensus guidelines on this topic have been published in recent years. The prevention and management of HbV infection in IbD patients is addressed in this review in order to address practical

关键词： Hepatitis b virus Inflammatory bowel disease Anti-tumor necrosis factor Prophylaxis Immunosuppressants

Prevalence of hepatocarcinoma-related hepatitis b virus mutants in patients in grey zone of treatment

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World Journal of Gastroenterology 2019年第38期25卷 5883-5896页

作者： Ana Isab.l Gil-García Antonio Madejón Irene Francisco-Recuero Ana lópez-lópez Emiliana Villafranca Miriam Romero Araceli García Antonio Olveira Rocío Mena Juan Ramón larrubia Javier García-Samaniego Hepatology Unit Hospital Universitario La PazMadrid 28046Spain Centro de Investigación biomédica en Red Instituto de Salud Carlos IIIMadrid 28029Spain Instituto de Investigación del Hospital Universitario la Paz Madrid 28046Spain biochemistry Department Faculty of MedicineUniversidad Autónoma de MadridMadrid 28029Spain Instituto de Genética Médica y Molecular Hospital Universitario La PazMadrid 28046Spain Translational Hepatology Unit Hospital General Universitario de GuadalajaraGuadalajara 19002Castilla-La ManchaSpain

bACKGROUND Antiviral treatment of patients with chronic hepatitis b(CHb)in the grey zone of treatment comands risk management in order to optimize the health *** this sense,the identification of HbV mutants related with an increased risk of hepatocellular carcinoma(HCC)could be useful to identify subpopulations with potential indication of antiviral *** To analyze the prevalence/persistence of hepatitis b virus(HbV)preS and basal core promoter(bCP)/precore/core variants associated to HCC development in CHb patients in the grey *** Work was designed as a longitudinal retrospective study,including 106 plasma samples from 31 patients with CHb in the grey zone of treatment:Hepatitis b e antigen negative,HbV-DNA levels between 12-20000 IU/ml,normal or discordant transaminase levels during follow up and mild/moderate necroinflammatory activity in liver biopsy or Fibroscan(up to 9.5 kPa).Serum HbVDNA was tested using the Abbott Real Time HbV Assay and the bCP/precore/core and the hepatitis b surface antigen(HbsAg)coding regions were analyzed in positive samples by PCR/b.lk-sequencing to identify the HCCrelated HbV *** High-risk HCC related mutants were detected in 24(77%)patients:19(61%)in the bCP/precore/core,and 7(23%)in the HbsAg coding region(2 preS1 and 5 preS2 deletions).The prevalence of preS deletions was genotype-dependent:3/5(60%)patients with preS2 deletions and 1/2 with preS1 deletions were infected with the HbV-E *** HbV-E was the most prevalent in sub-Saharan patients,a correlation between preS deletions and ethnicity was also found:6/8(75%)sub-Saharan vs 1/19(5%)Caucasian patients had preS deletions(P=0.00016).Remarkably,this correlation was maintained in those patients infected with HbV-A,a minor genotype in sub-Saharan patients:2/2 patients infected with HbV-A from West Africa vs 0/6 of Caucasian origin had preS *** HCC related variants were the major strains and persisted over time(up to 48 mo).Pa

关键词： Hepatitis b virus Hepatocellular carcinoma PreS deletions Hepatitis b virus treatment Grey zone

Improvement in the corrosion protection and bactericidal properties of AZ91D magnesium alloy coated with a microstructured polypyrrole film

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Journal of Magnesium and Alloys 2018年第1期6卷 15-22页

作者： A.D.Forero lópez I.l.lehr l.I.brugnoni S.b.Saidman Instituto de Ingeniería Electroquímica y Corrosión(INIEC) Departamento de Ingeniería QuímicaUniversidad Nacional del SurAv.Alem 12538000 Bahía BlancaArgentina Instituto de Investigaciones biológicas y biomédicas del Sur(INbIOSUR) Departamento de BiologíaBioquímica y FarmaciaUniversidad Nacional del SurSan Juan 6708000 Bahía BlancaArgentina

In this work hollow rectangular microtubes of polypyrrole(PPy)films were potentiostatically electrodeposited on magnesium alloy AZ91D in salicylate *** substrate was previously anodized under potentiostatic conditions in a molybdate solution in order to improve the adherence of *** the duplex film was modified by the incorporation of silver *** obtained coatings were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopies(XPS)and the antimicrobial activity against the bacteria Escherichia coli was *** corrosion protection properties of the coatings were examined in Ringer solution by monitoring the open circuit potential,polarization techniques and electrochemical spectroscopy(EIS).The duplex coating presents an improved anticorrosive performance with respect to the PPy *** best results concerning corrosion protection and antibacterial activity were obtained for the silver-modified composite coating.

关键词： Polypyrrole Duplex coating AZ91D alloy Corrosion resistance Antibacterial properties

Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato Socodato João b.Relvas Institute of Research and Innovation in Health(i3S)and Institute for Molecular and Cell biology(IbMC) University of PortoPortoPortugal Department of biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(CNS)and the immune *** exploration is particularly significant in understanding microglia,the CNS’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).Here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

Influence of agriculture and aquaculture activities on the response of autotrophic picoplankton in laguna Macapule, Gulf of California (Mexico)

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Ecological Processes 2017年第1期6卷 41-51页

作者： Aída Martínez-lópez Cristian Hakspiel-Segura Diana Cecilia Escobedo-Urías bárbara González-Acosta Centro Interdisciplinario de Ciencias Marinas-IPN(CICIMAR) Av.IPN s/nCol.Playa Palo de Santa RitaLa PazB.C.S.23096Mexico Centro de Interdisciplinario de Investigación para el Desarrollo Integral Regional (CIIDIR–Unidad Sinaloa)Bulevar Juan de Dios Bátiz Paredes 250Col.San JoachinGuasaveSinaloa 81101Mexico

Introduction:The lagoon is a component of coastal zones,whose populations of autotrophic picoplankton(APP)remain largely *** lagoons display high-nutrient productivity and additionally may also be subjected to anthropogenic *** study selected laguna Macapule,located on the eastern shore in the mid-region of the Gulf of California,due to the fact that a drainage network servicing the surrounding agricultural region(>230,000 hectares under cultivation)directs irrigation runoff,shrimp farm effluents,and urban wastewater containing large quantities of nutrients to be discharged into this *** propose to identify the APP’s response to various types of environmental and anthropogenic influence in this highly impacted coastal ***:Two sites(separated by 2.7 km)were monitored from December 2007 to December ***,located at the entrance to laguna Macapule(oceanic influence)and the other a discharge canal(eutrophic conditions)inside the lagoon at El Tortugó***:APP was the numerically dominant phytoplankton fraction(15×106 to 620×106 cells l−1)with coccoidal cyanobacteria as the dominant fraction throughout the *** levels were reached in spring-early autumn and they were the second largest contributor to *** of APP cells corresponds to the lagoon’s eutrophic *** numbers and a higher average of APP were recorded at the El Tortugón channel during the warm season(months with SST higher than 24°C).The general positive relationship of the APP’s annual cycle at both sites as well as a negative relationship with heterotrophic nanoflagellates(HNF)abundance,supports the idea that natural forcing,in particular sea surface temperature(SST)is the predominant influences on APP’s seasonal ***:Distinguishable significant differences in APP abundances and nutrients were recognizable between the two *** interplay of these variables contributed to lower densities of APP in winter and high de

关键词： Aquaculture Autotrophic picoplankton Eutrophic conditions Heterotrophic ciliates Heterotrophic nanoflagellates Urea

Raman spectroscopy of isolated carbyne chains confined in carbon nanotubes:Progress and prospects

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Chinese Physics b 2022年第12期31卷 532-542页

作者： Johannes M.A.lechner Pablo Hernández lópez Sebastian Heeg Institut fur Physik and IRIS Adlershof Humboldt Universitat zu Berlin12489 BerlinGermany

Carbyne is an infinitely long linear chain of carbon atoms with sp1hybridization and the truly one-dimensional allotrope of *** obtaining freestanding carbyne is still an open challenge,the study of confined carbyne,linear chains of carbon encapsulated in carbon nanotubes,provides a pathway to explore carbyne and its remarkable properties in a well-defined *** this review,we discuss the basics and recent advances in studying single confined carbyne chains by Raman spectroscopy,which is their primary spectroscopic characterization *** highlight where single carbyne chain studies are needed to advance our understanding of confined carbyne as a material system and provide an overview of the open questions that need to be addressed and of those aspects currently under debate.

关键词： carbyne linear carbon chains carbon nanotubes Raman spectroscopy

Importance of the Development of Veterinary Toxicology in Argentina

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biomedical and Environmental Sciences 1989年第1期2卷 7-16页

作者： TOMáS A.lópez Instituto

The different types of toxic substances that affect farm animals in Argentina are described. These substances include (a) toxic plants, such as Solanum glaucophyllum. baccharis coridifolia, Festuca arundinacea; (b) mycotoxins, such as zearalenone, tremorgenic mycotoxins, and ergoalkaloid; (c) trace elements, such as fluorine, copper, molybdenum, and arsenic; and (d) others, such as toxic algae and pesticides. The direct and indirect economic loss of farm animals associated with these toxic substances in Argentina is roughly estimated at 50 million dollars a year. A number of recommendations are made to ameliorate the situation. 1989 Academic Press, Inc.

关键词： In Importance of the Development of Veterinary Toxicology in Argentina