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Applied Mathematics 2017年第3期8卷 358-376页

作者： Francisco eduardo Castillo-Santos miguel Angel Dela Rosa Iván Loreto-Hernández División Académica de Ciencias Básicas CONACyT-UJAT Cunduacán México

In this paper, we prove the existence of a limit cycle for a given system of differential equations corresponding to an asymmetrical intraguild food web model with functional responses Holling type II for the middle and top predators and logistic grow for the (common) prey. The existence of such limit cycle is guaranteed, via the first Lyapunov coefficient and the Andronov-Hopf bifurcation theorem, under certain conditions for the parameters involved in the system.

关键词： Hopf’s Bifurcation Limit Cycle Intraguild Model

Role of T cell death in maintaining immune tolerance during persistent viral hepatitis

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World Journal of Gastroenterology 2013年第12期19卷 1877-1889页

作者： Juan Ramón Larrubia Megha Uttam Lokhande Silvia García-Garzón Joaquín Miquel Dolores Subirá eduardo Sanz-de-Villalobos Translational Hepatology Unit Guadalajara University Hospital University of Alcalá

Virus-specific T cells play an important role in the resolution of hepatic infection. However, during chronic hepatitis infection these cells lack their effector functions and fail to control the virus. Hepatitis B virus and hepatitis C virus have developed several mechanisms to generate immune tolerance. One of these strategies is the depletion of virus-specific T cells by apoptosis. The immunotolerogenic liver has unique property to retain and activate na ve T cell to avoid the over reactivation of immune response against antigens which is exploited by hepatotropic viruses to persist. The deletion of the virus-specific T cells occurs by intrinsic (passive) apoptotic mechanism. The pro-apoptotic molecule Bcl-2 interacting mediator (Bim) has attracted increasing attention as a pivotal involvement in apoptosis, as a regulator of tissue homeostasis and an enhancer for the viral persistence. Here, we reviewed our current knowledge on the evidence showing critical role of Bim in viral-specific T cell death by apoptotic pathways and helps in the immune tolerance.

关键词： T cell death Specific cytotoxic T lymphocytes Hepatitis C virus immune tolerance Apoptosis Bcl-2 interacting mediator Liver tolerance Apoptotic pathways Viral hepatitis

Propagation and Confinement of Electric Field Waves along One-Dimensional Porous Silicon Hybrid Periodic/Quasiperiodic Structure

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Optics and Photonics Journal 2013年第2期3卷 1-12页

作者： José Escorcia-García miguel eduardo Mora-Ramos Centro de Investigación en Energía Universidad Nacional Autónoma de México Temixco Morelos México Física Teórica y Aplicada Escuela de Ingeniería de Antioquia Sede Las Palmas Envigado Antioquia Colombia

Selective spatial confinement of the electric field intensity is theoretically obtained for the light propagation along hybrid structures conformed by periodic and Fibonacci quasiperiodic dielectric multilayers. Sandwich-like configurations featuring periodic-quasiperiodic-periodic as well as quasiperiodic-periodic-quasiperiodic designs exhibit spatial localization of a large percent of the optical signal within specific zones of the hybrid system. Such a feature might be of interest in the pursuing of lasing devices based on porous silicon. It is found that the electric field confinement does not only depend on the quality of the defect or a particular transmission mode observed in the reflectivity spectra. We show that it is possible to enhance the electric field confinement solely varying the angle of incidence. The possibility of realizing finite photonic crystals with reduced size and very well defined band gap by means of a quasiperiodic-periodic-quasiperiodic hybrid multilayer is also revealed.

关键词： Optical Properties Electric Field Multilayers Hybrid Structures

Renal function and choroidal thickness using swept-source optical coherence tomography in diabetic patients

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International Journal of Ophthalmology(English edition) 2019年第6期12卷 985-989页

作者： Antonio Manuel Garrido-Hermosilla mariola Méndez-Muros Estanislao Gutiérrez-Sánchez Cristóbal Morales-Portillo maría Jesús Díaz-GrAnDa eduardo Esteban-González Isabel Relimpio-López maría Asunción martínez-Brocca Enrique Rodríguez-de-la-Rúa-Franch Department of Ophthalmology Virgen Macarena University HospitalSeville 41009Spain OftaRed Institute of Health Carlos IIIMadridSpain Department of Endocrinology and nutrition Virgen Macarena University HospitalSeville 41009Spain

AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. RESULTS: A significant negative correlation was mainly observed between several choroidal thicknesses, age(Pnd ocular AXL(Pn the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1 c(Pnd albuminuria(PnCLUSIOn: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients.

关键词： choroidal thickness renal function swept-source optical coherence tomography spectral-domain optical coherence tomography diabetes mellitus

Relationships between soil pollution by heavy metals and melanin-dependent coloration of a fossorial amphisbaenian reptile

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Integrative Zoology 2022年第4期17卷 596-607页

作者： JosémarTÍn Pablo RECIO Gonzalo RODRÍGUEZ-RUIZ Isabel BARJA eduardo GUTIÉRREZ Luis VGARCÍA Departamento de Ecología Evolutiva Museo Nacional de Ciencias NaturalesCSICMadridSpain Departamento de Zoología Facultad de BiologíaUniversidad Autónoma de MadridMadridSpain Centro de Investigación en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autónoma de MadridMadridSpain Departamento de Biogeoquímica Ecología Vegetal y MicrobianaInstituto de Recursos Naturales y Agrobiología de SevillaCSICSevillaSpain

Melanin is the basis of coloration in many animals,and although it is often used in communication,thermoregulation,or camouflage,melanin has many other physiological *** example,in polluted habitats,melanin can have a detoxifying *** coloration would help to sequester in the skin the heavy metal contaminants from inside the body,which will be expelled to the exterior when the skin is ***,animals should have evolved more melanic colorations in more polluted habitats(“industrial melanism”hypothesis).We examined whether the fossorial amphisbaenian reptile,Trogonophis wiegmanni,is able to eliminate heavy metals,derived from soil pollution by seagull depositions,through sloughing its *** results suggest a covariation between levels of soil pollution by heavy metals and the concentration of heavy metals in the sloughed skins of *** suggests that amphisbaenians may expel heavy metals from their bodies when they slough the *** also tested whether amphisbaenians inhabiting soils with higher levels of heavy metal pollution had darker(melanin-dependent)body ***,contrary to predictions from the“industrial melanization”hypothesis,we found a negative relationship between soil pollution and proportions of melanic *** contradictory result could,however,be explained because heavy metals have endocrine disruption effects that increase physiological stress,and higher stress levels could result in decreased *** suggest that although amphisbaenians might have some detoxifying mechanism linked to melanin in the skin,this process might be negatively affected by stress and result ineffective under conditions of high soil pollution.

关键词： amphisbaenians coloration fossorial reptiles heavy metals melanin soil pollution

Changes in rainfall partitioning caused by the replacement of native dry forests of Lithraea molleoides by exotic plantations of Pinus elliottii in the dry Chaco mountain forests, central Argentina

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Journal of Arid Land 2020年第5期12卷 717-729页

作者： Samia S CORTÉS Juan I WHITWORTH-HULSE eduardo L PIOVAnO Diego E GURVICH Patricio n MAGLIAnO Land Science Research Center(CICTERRA-COnICET)and national University of Córdoba Av.Vélez Sarsfield 1611X5016GCA CórdobaArgentina Multidisciplinary Institute of Plant Biology National University of Córdoba and CONICETCC 495X5000JJC CórdobaArgentina Environmental Study Group Institute of Applied Maths of San LuisNational University of San Luis and CONICETEjército de los Andes 950D5700HHW San LuisArgentina Department of Biology Faculty of ChemistryBiochemistry and PharmacyNational University of San LuisEjército de los Andes 950D5700HHW San LuisArgentina

The replacement of native dry forests by commercial(exotic)tree plantations could generate changes in rainfall partitioning,which further affects the water *** this study,we determined(i)the rainfall partitioning into interception,throughfall and stemflow,(ii)the role of rainfall event size on rainfall partitioning,(iii)the pH of water channelized as throughfall and stemflow,and(iv)the runoff in Lithraea molleoides(a native species)and Pinus elliottii(an exotic species)stands in the dry Chaco mountain forests,central *** average,interception,throughfall and stemflow accounted for 19.3%,79.5%and 1.2%of the gross rainfall in *** stand,and 32.6%,66.7%and 0.7%of the gross rainfall in *** stand,*** of interception,throughfall and stemflow presented positive linear relationships with the increment of rainfall event size for both tree species(Pn all cases).Percentages of interception,throughfall and stemflow were all related to the increment of rainfall event size,showing different *** increasing rainfall event size,interception exponentially decreased,throughfall asymptotically increased and stemflow linearly *** *** and *** stands presented significant differences in the pH values of water channelized as throughfall(6.3 vs.6.7,respectively;Pnd stemflow(4.5 vs.5.8,respectively;Pnoff occupied only 0.3%of the gross rainfall in *** stand and was zero in *** *** results showed that the native species *** presented 13.6%more water reaching the topsoil(i.e.,net rainfall;net rainfall=gross rainfall-interception-runoff)than the exotic species *** study improves our understanding of the effects of native vegetation replacement on the local water balance in the dry forest ecosystems.

关键词： drylands ecohydrology land use changes spatial heterogeneity water-limited environments

Recognition of trench basins in collisional orogens:Insights from the Yarlung Zangbo suture zone in southern Tibet

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Science China Earth Sciences 2020年第12期63卷 2017-2028页

作者： Xiumian Hu Wei An eduardo Garzanti Qun Liu Institute of Continental Geodynamics State Key Laboratory for Mineral Deposits ResearchSchool of Earth Sciences and EngineeringNanjing UniversityNanjing210023China School of Resources and Environmental Engineering Hefei University of TechnologyHefei230009China Department of Earth and Environmental Sciences Universitàdi Milano-BicoccaMilano20126Italy

Trench basin,as an important sedimentary repository in oceanic subduction zones,documents faithfully the evolution of paleodrainage and paleogeographic *** of the frequent intense deformation during and after deposition,the recognition of trench-basin strata in orogenic belts is quite *** trench-fill deposits have been identified from the Yarlung Zangbo suture in southern Tibet,which can be classified into two types based on major differences in formation timing and tectonic *** first type developed during subduction of the neotethyan oceanic slab in the Cretaceous(e.g.,the Jiachala,Rongmawa,and Luogangcuo formations),and the second type developed during the initial stage of the India-Asia collision in the Palaeogene(e.g.,the Sangdanlin-Zheya formations).The former was originally deposited on the subducting oceanic crust and then accreted as tectonic slices into the subduction complex;the latter was deposited unconformably on the continental margin of the subducting Indian plate and then involved in the subduction complex during the continental *** lithologies of trench-basin fills include abyssal chert,siliceous shale,silty to sandy turbidites,debris flows deposits,and slump deposits without *** feeding these basins were chiefly from the uplifted terrane in the upper *** paper summarizes the geological features of trench basins developed in southern Tibet and proposes criteria for recognizing trench-basins in collisional orogens.

关键词： Trench basin.Provenance analysis Yarlung Zangbo suture zone Southern Tibet Cretaceous-Paleocene Himalayan orogen

Morphological and biochemical effects of weekend alcohol consumption in rats: Role of concentration and gender

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World Journal of Hepatology 2018年第2期10卷 297-307页

作者： José A Morales-González maría de Lourdes Sernas-Morales ángel Morales-González Laura Ligía González-López eduardo Osiris Madrigal-Santillán nancy Vargas-Mendoza Tomás Alejandro Fregoso-Aguilar Liliana Anguiano-Robledo eduardo Madrigal-Bujaidar Isela álvarez-González Germán Chamorro-Cevallos Laboratorio de Medicina de Conservación Escuela Superior de Medicina Instituto Politécnico Nacional Escuela Superior de Cómputo Instituto Politécnico Nacional área Académica de nutrición ICSa Universidad Autónoma del Estado de Hidalgo Depto. de Fisiología Laboratorio de Hormonas y Conducta ENCB campus Zacatenco Instituto Politécnico Nacional Laboratorio de Farmacología Molecular Sección de Estudios de Posgrado e Investigación Escuela Superior de Medicina-Instituto Politécnico Nacional Laboratorio de Genética Escuela Nacional de Ciencias Biológicas IPN Departamento de Farmacia Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional

AIM To examine the association between weekend alcohol consumption and the biochemical and histological alterations at two different concentrations of alcohol in both genders in *** Wistar rats weighing 170-200 g were divided into groups as follows:(1) Control groups; and(2) weekend alcohol-consumption group: 2 d/weekly per 12 wk, at two different concentrations:(1) Group of males or females with a consumption of a solution of alcohol at 40%; and(2) group of males or females with a consumption of a solution of alcohol at 5%. At the end of the experiment, serum and liver samples were obtained. The following enzymes and metabolites were determined in serum: Alanine Aminotransferase(ALT), Aspartate Aminotransferase(AST), Lactate Dehydrogenase, and Gamma-Glutamyltransferase, and glucose, triglycerides, cholesterol, bilirubin, and albumin. Liver samples from each group were employed to analyze morphological abnormalities by light *** In all of the weekend alcohol-consumption groups, AST activity presented a significant, 10-fold rise. Regarding ALT activity, the groups with weekend alcohol consumption presented a significant increase that was six times greater. Bilirubin levels increased significantly in both groups of females. We observed a significant increase in the parameters of fatty change and inflammation due to weekend alcohol consumption. Only the group of females that consumed alcohol at 40% presented slight hepatocel ular disorganization COnCLUSIOn The results obtained herein provide solid evidence that weekend alcohol consumption gives rise to liver damage, demonstrated by biochemical and histological alterations, first manifested acutely, and prolonged weekend alcohol consumption can cause greater, irreversible damage.

关键词： Weekend alcohol consumption Liver morphology Transaminases Damage

Transmission line protection challenges influenced by inverter-based resources:a review

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Protection and Control of Modern Power Systems 2022年第1期7卷 406-422页

作者： Juan Carlos Quispe eduardo Orduña Institute of Electrical and Energy-COnICET Universidad Nacional de San JuanSan JuanArgentina Universidad Tecnológica del Perú LimaPeru

High penetration of renewable energy sources(RES)leads to new challenges for protection *** schemes are typically designed according to the dynamic behavior of rotating machines as generation sources,while the RES dynamic response,mainly governed by inverters,is not ***,some relevant algorithms of transmission line protection are experiencing challenges because of the fact that magnitude and phase angle com-parison,amount of negative-sequence,and short-circuit current level are affected by the ***,an in-depth study of this issue is necessary,one which considers the main causes and new methodological criteria *** work presents an extensive literature review of the evaluation of electrical protection performance and the effects of RES connected to a power grid through *** data on many representative publications related to this topic are obtained to show the current research lines and their proposed *** addition,this work identi-fies the main protection functions affected and describes the new protection schemes that consider ***,an analysis and discussion of the selected bibliography are presented.

关键词： Inverter-based resources Inverter control system Photovoltaic plant Transmission line protection Wind farm

Iterated Inverse Images of Plane Curve Singularities

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2319-2328页

作者： eduardo CASAS-ALVERO Joaquim ROE Departament d＇Algebra i Geometria Universitat de Barcelona Gran Via 585 08007 Barcelona Spain Departament de Matematiques Universitat Autonoma de Barcelona 08193 Bellaterra （Barcelona） Spain

We describe the evolution of certain multiplicities and intersection numbers of plane curve singularities under the iterated action of an analytic morphism.

关键词： Plane curve singularity analytic morphism dynamics of intersection