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HVSr analysis of pumice sands for sediment depth characterization:A case study for Guadalajara,mexico

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado m. Alejandro ram.rez-Gaytan Adolfo Preciado Christian r.Escudero Departamento de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico Departamento de Ciencias Computacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico Departamento del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSr)methodology is used here to characterize pumice soils and to image the three-dimensional surface geometry of Guadalajara,*** to other Latin Am.rican cities,Guadalajara is exposed to high seismic risk,with the particularity of being the largest urban settlement in Latin Am.rica built on pumice *** has not yet been tested to characterize subsoil depths in pumice *** to the questionable use of traditional geotechnical tests for the analysis of pumice soils,HVSr provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak amplitude(A0)are used to constrain the depth of the major impedance contrast that represents the interface between bedrock and pumice *** were compared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estimated on the riverbanks that cross the city,reveals different subsoil thickness that could have an impact on different site responses on riverine areas to an eventual *** and academic efforts are combined in this work to characterize depth sediments,an important parameter that impacts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pumice soil characterization

Algorithm for repairing the damaged images of grain structures obtained from the cellular automata and measurement of grain size

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International Journal of minerals,metallurgy and materials 2012年第10期19卷 899-907页

作者： A.ram.rez-López m.A.rom.ro-romo D.muñoz-Negron S.López-ram.rez r.Escarela-Pérez C.Duran-Valencia Department of materials and Energy Metropolitan Autonomous UniversityMexico City 02200Mexico Department of Industrial Engineering Technological Autonomous Institute of MexicoMexico City 01080Mexico Department of molecular Engineering Mexican Institute of PetroleumMexico City 07730Mexico

Computational models are developed to create grain structures using mathematical algorithms based on the chaos theory such as cellular automaton, geometrical models, fractals, and stochastic methods. Because of the chaotic nature of grain structures, some of the most popular routines are based on the monte Carlo method, statistical distributions, and random walk methods, which can be easily programmed and included in nested loops. Nevertheless, grain structures are not well defined as the results of computational errors and num.rical incon- sistencies on mathematical methods. Due to the finite definition of numbers or the num.rical restrictions during the simulation of solidifica- tion, damaged images appear on the screen. These images must be repaired to obtain a good measurement of grain geometrical properties. Some mathematical algorithms were developed to repair, measure, and characterize grain structures obtained from cellular automata in the present work. An appropriate measurement of grain size and the corrected identification of interfaces and length are very important topics in materials science because they are the representation and validation of mathematical models with real samples. As a result, the developed al- gorithms are tested and proved to be appropriate and efficient to eliminate the errors and characterize the grain structures.

关键词： grain size and shape image restoration mathematical algorithms cellular automata solidification

Efficacy of antimicrobials in preventing resistance in solid organ transplant recipients:A systematic review of clinical trials

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World Journal of Transplantation 2025年第1期15卷 156-164页

作者： Carlos m Ardila Pradeep K Yadalam Jaime ram.rez-Arbelaez Department of Basic Sciences Faculty of Dentistry Biomedical Stomatology Research GroupUniversidad de Antioquia U de AMedellín 0057Colombia Department of Postdoctoral Program CIFE University CenterCuernavaca 62330MorelosMexico Department of Periodontics Saveetha Dental CollegeSaveetha Institute of Medical and HealthSIMATSSaveetha UniversityChennai 600077Tamil NaduIndia Department of Transplantation Hospital San Vicente FundaciónRionegro 054047Colombia

BACKGrOUND In the absence of effective antimicrobials,transplant surgery is not viable,and antirejection immunosuppressants cannot be administered,as resistant infections com.romise the life-saving goal of organ *** To evaluate the efficacy of antimicrobials in preventing resistance in solid organ transplant *** A systematic review was conducted using a search methodology consistent with the preferred reporting items for systematic reviews and *** review included randomized clinical trials that evaluated the efficacy of antimicrobial agents(prophylactic or therapeutic)aimed at preventing antimicrobial *** search strategy involved analyzing multiple databases,including Pubmed/mEDLINE,Web of Science,Embase,Scopus,and SciELO,as well as examining gray literature sources on Google Scholar.A com.rehensive electronic database search was conducted from the databases’inception until may 2024,with no language *** After the final phase of the eligibility assessment,this systematic review ultimate-ly included 7 articles.A total of 2318 patients were *** most studied microorganisms were cytomegalovirus,although vancomycinresistant enterococci,Clostridioides difficile,and multidrug-resistant Enterobacterales were also *** antimicrobials used in the interventions were mainly m.ribavir,valganciclovir,gancic-lovir,and *** concern,all clinical trials showed significant proportions of resistant microorga-nisms after the interventions,with no statistically significant differences between the groups(mean resistance 13.47%vs 14.39%),except for two studies that demonstrated greater efficacy of m.ribavir and valganciclovir(mean resistance 22.2%vs 41.1%in the control group;Preported deaths in three clinical trials were 75,and there were 24 graft rejections in two *** All clinical trials reported significant proportions of antimicrobial-resistant microor

关键词： Antimicrobial resistance Antimicrobials Antivirals Solid organ transplant recipients Infections microorganisms Cytomegalovirus

Tropical ash(Fraxinus udhei)invading Andean forest remnants in Northern South Am.rica

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Ecological Processes 2018年第1期7卷 152-164页

作者： Kelly A.Saavedra-ram.rez AndrésEtter Alberto ram.rez Depa rtamento de Ecologia y Territoto Pontificia Universidad averianaBogotaColomba

Introduction:Exotic invasive species represent a major driver of the loss of biological diversity and services provided by ecosystems *** important cause of species becoming invasive is the development of comm.rcial afforestation projects using fast-growing and adaptable exotic species,which may become invasive impacting natural *** tropical ash(Fraxinus uhdei),native to méxico,has been widely introduced to Colombia and other countries for timber,live fences,and urban *** is now common in many areas of the tropical mountains and has been observed expanding into native forests in *** study examined the invasion pattern and the demographic structure of tropical ash in remnant Andean forests in Colombia,to find out factors associated with the invasion *** analysis took into account biotic and physical factors:distance to propagule source,vegetation cover types,and understory and canopy ***:Although the reproductive strategy of the tropical ash is of“r”type with low survival rates,the results show evidence for an active process of invasion characterized by an aggregated distribution pattern dominated by seedlings and juvenile *** study shows the existence of an interaction between the distance to propagule source and the vegetation cover,which has an additive effect on the demographic structure of the ***:This study suggests an active invasion process by the exotic tree tropical ash into a remnant of sub-humid forests in the Andean *** results showed an expanding population process with a decreasing average age from propagule sources and mature reproductive individuals within the native forest,which bring new individuals that are colonizing new areas and advancing into the *** research points to the need for urgent plant intervention on two aspects:the use of the tropical ash and the management of the invasion process in native forests.

关键词： Andean forest Demographic structure Fraxinus uhdei Exotic species Plant biological invasions Invasion pattern

Amyotrophic lateral sclerosis,a neurodegenerative motor neuron disease with retinal involvement

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Neural regeneration research 2022年第5期17卷 1011-1012页

作者： Ana I.ram.rez rosa de Hoz Pilar rojas Juan J.Salazar Instituto de Investigaciones Oftalmológicas ramón Castroviejo.Universidad Complutense de madrid MadridSpain Facultad deÓptica y Optometría.Departamento de Inmunología Oftalmología y ORL.Universidad Complutense de MadridMadridSpain Hospital General Universitario Gregorio m.rañón Instituto Oftálmico de MadridMadridSpain

Amyotrophic lateral sclerosis(ALS)is a neurodegenerative disease that damages the motor neurons,the spinal cord,the cerebellum,and some areas of the ***,m.re recent studies show that it can also affect the visual syst... 详细信息

关键词： visual problems involvement

Solution of the Center Problem for a Class of Polynomial Differential Systems

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Acta mathematica Sinica,English Series 2024年第7期40卷 1685-1696页

作者： Chang Jian Liu Jaume Llibre rafael ram.rez Valentín ram.rez School of mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai519086P.R.China Departament de matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain Departament d’Enginyeria Informàtica i matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Consider the polynomial differential system of degree m of the form x=-y(1+μ(a_(2)x-a_(1)y))+x(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),y=x(1+μ(a_(2)x-a_(1)y))+y(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),whereμandνare real numbers such that(μ^(2)+v^(2))(μ+v(m-2))(a_(1)^(2)+a_(2)^(2))≠m>2 andΩ_(m−1)(x,y)is a homogenous polynomial of degree m−1.A conjecture,stated in *** Equations 2019,suggests that whenν=1,this differential system has a weak center at the origin if and only if after a convenient linear change of variable(x,y)→(X,Y)the system is invariant under the transformation(X,Y,t)→(−X,Y,−t).For every degree m we prove the extension of this conjecture to any value ofνexcept for a finite set of values ofμ.

关键词： Center problem polynomial differential system

retinal microglial activation in glaucoma:evolution over time in a unilateral ocular hypertension model

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Neural regeneration research 2022年第4期17卷 797-799页

作者： JoséA.Fernández-Albarral Ana I.ram.rez rosa de Hoz Juan J.Salazar Instituto de Investigaciones Oftalmológicas ramón Castroviejo Universidad Complutense de MadridMadridSpain Facultad deÓptica y Optometría Departamento de InmunologíaOftalmología y ORLUniversidad Complutense de MadridMadridSpain

Glaucoma is a neurodegenerative chronic pathology,characterized by the loss of retinal ganglion cells(rGC),which leads to an irreversible vision field *** increased intraocular pressure(IOP)constitutes its main risk ***,the main treatments for glaucoma are focused on decreasing IOP;nevertheless,the progression of the disease continues,despite IOP *** fact shows the existence of other factors that could contribute to the advance of glaucomatous *** early diagnostics,the use of neuroprotective therapies,and knowledge of the pathological processes are the major challenges associated with the management of this *** pathogenic mechanisms have been proposed to be responsible for rGC death,including oxidative stress,mitochondrial dysfunction,glutamate excitotoxicity,and neuroinflammation(Casson et al.,2012).

关键词： irreversible oxidative activation

Geom.rphic indices and relative tectonic uplift in the Guerrero sector of the mexican forearc

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Geoscience Frontiers 2017年第4期8卷 885-902页

作者： Krzysztof Gaidzik m.ría Teresa ram.rez-Herrera Laboratorio Universitario de Geofísica Ambiental & Instituto de Geografía Universidad Nacional Autónoma de MéxicoCiudad Universitaria Berkeley Seismological Laboratory Department of Earth and Planetary ScienceUniversity of California Berkeley

Tectonically active areas,such as forearc regions,commonly show contrasting relief,differential tectonic uplift,variations in erosion rates,in river incision,and in channel gradient produced by ongoing tectonic ***,information on the tectonic activity of a defined area could be derived via landscape *** study uses topography and geom.rphic indices to extract signals of ongoing tectonic deformation along the mexican subduction forearc within the Guerrero *** this purpose,we use field data,topographical data,knickpoints,the ratio of volume to area（rva）.the stream-length gradient index（St）,and the normalized channel steepness index（k_（sn））.The results of the applied landscape analysis reveal considerable variations in relief,topography and geom.rphic indices values along the Guerrero sector of the mexican subduction *** argue that the reported differences are indicative of tectonic deformation and of variations in relative tectonic uplift along the studied forearc.A significant drop from central and eastern parts of the study area towards the west in values of r_（VA）（from ~500 to^300）,St（from ~500 to ca.400）,maximum St（from ~1500-2500 to ~ 1000） and k_（sn）（from ~150 to ~100） denotes a decrease in relative tectonic uplift in the same *** suggest that applied geom.rphic indices values and forearc topography are independent of climate and *** mechanisms responsible for the observed variations and inferred changes in relative forearc tectonic uplift call for further studies that explain the physical processes that control the forearc along strike uplift variations and that determine the rates of *** proposed methodology and results obtained through this study could prove useful to scientists who study the geom.rphology of forearc regions and active subduction zones.

关键词： relative tectonic uplift Forearc Active tectonics Geom.rphic index Drainage network mexican subduction zone

resveratrol as an inductor of autophagy: is there a unique pathway of activation?

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Neural regeneration research 2021年第1期16卷 101-103页

作者： Narayana Pineda-ram.rez Penélope Aguilera Laboratorio de Patología Vascular Cerebral.Instituto Nacional de Neurología y Neurocirugía manuel Velasco Suárez Ciudad de MéxicoMéxico

Autophagy is a process of cellular degradation for the removal of damaged components and eventual recycling of the resulting molecules that help to the maintenance of cellular *** this pathway,proteins with relatively long half-life and whole organelles(e.g.,mitochondria,peroxisomes,and ribosomes)are degraded in the cytoplasm for the continuous turnover of cellular structures to facilitate their ***,the beneficial effect of autophagy goes beyond cellular“cleaning”and resides to a large extent on its ability to recycle cell components back into the ***,autophagy is a fundamental mechanism to regulate cellular functions,including DNA repair,proliferation,differentiation,em.ryonic development,and the immune response.

关键词： homeostasis activation autophagy