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Journal of Arid land 2020年第1期12卷 104-114页

作者： Mónica I MIGUEl-VÁZQUEZ yasser s lópez de olmos r Gilberto OCAMPO department of Biology Basic Sciences CenterAutonomous University of Aguascalientes940 University AvenueAguascalientes 20130Mexico Biological and Health sciences PhD Program Department of BiologyBiological and Health Sciences DivisionAutonomous Metropolitan UniversityIztapalapa 09340Mexico

Talinopsis frutescens(Anacampserotaceae,a family that is close related to Cactaceae)is a succulent species endemic to North *** aim of this study was to explore,using Ecological Niche Modeling(ENM),changes in potential distribution ranges considering different climate scenarios:past conditions during the last Inter Glacial(lIG)and the last Glacial Maximum(lGM),the present and projections for 2070(rCP 2.6 to 8.5).A pattern of contraction is observed during the lIG,which agrees with other studies focused in species from arid *** pattern was followed by a migration towards the south during the lGM and a possible recent expansion to the north as is observed in the present *** future projections show the same contraction and fragmentation patterns,resulting in three discontinuous areas:the northern part of the Chihuahuan desert,the southern-central part of the Mexican Plateau,and the smallest one in the Tehuacán-Cuicatlán *** projections for future scenarios agree with other studies and support that global climate change tends to alter the current distribution of arid environment species.

关键词： Anacampserotaceae Caryophyllales ecological niche modeling succulent plants potential distribution

The animal cachexia score(ACAsCO)

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Animal Models and Experimental Medicine 2019年第3期2卷 201-209页

作者： Angelica Betancourt sílvia Busquets Marta Ponce Míriam Toledo Joan Guàrdia‐olmos Maribel Peró‐Cebollero Francisco J.lópez‐soriano Josep M.Argilés Cancer research Group Departament de Bioquímica i Biomedicina MolecularFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain Institut de Biomedicina de la Universitat de Barcelona BarcelonaSpain Advanced statistical Data Analysis Applied to Psychology Departament de Metodologia de les Ciències del ComportamentFacultat de PsicologiaUniversitat de BarcelonaBarcelonaSpain Institut de recerca en Cervell Cogniciói Conducta(IR3C)BarcelonaSpain

Background:None of the published studies involving cancer cachexia experimental models have included a measure of the severity of the syndrome like the scoring system previously developed for human *** aim of the present investigation was to define and validate a cachexia score usable in both rat and mouse tumor ***:In order to achieve this goal,we included in the study one rat model(Yoshida AH‐130ascites hepatoma)and two mouse models(lewis lung carcinoma and Colon26 carcinoma).The Animal cachexia score(ACAsCO)includes five components:(a)body and muscle weight loss,(b)inflammation and metabolic disturbances,(c)physical performance,(d)anorexia,and(e)quality of life measured using discomfort symptoms and behavioral ***:Using the ACAsCO values,three cut‐off values were estimated by applying hierarchical cluster *** groups were originally described,one exactly below the observed mean,a second exactly over the mean,and two other groups adjusted to every cue(inferior and superior).The three cut‐off values were estimated through maximization of the classification *** was accomplished by using a similarity matrix based on the metric properties of the variables and assuming multinormal *** results show that the four groups were:no cachexia,mild cachexia,moderate cachexia and advanced ***:The results obtained allow us to conclude that the score could be very useful as an endpoint in pre‐clinical studies involving therapeutic strategies for cancer *** potential usefulness of ACAsCO relates to the primary endpoint in pre‐clinical cancer cachexia drug evaluations.

关键词： anorexia cachexia classification physical performance quality of life score wasting weight loss

Point Charge between Two Grounded and Conducting Planes Forming a 60°Angle and for Yukawa’s Potential and Coulomb’s Potential

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Journal of Electromagnetic Analysis and Applications 2021年第4期13卷 57-66页

作者： Miguel Angel lópez-Mariño Omar olmos lópez José Manuel Pardo regueiro Tecnologico de Monterrey Escuela de Ingeniería y Ciencias Chihuahua México Tecnologico de Monterrey Escuela de Ingeniería y Ciencias Monterrey México Tecnologico de Monterrey Escuela de Ingeniería y Ciencias Torreón México

For a point charge between two grounded conductor planes forming a 60° angle, the potential and electric field generated by point charge for Yukawa’s potential (e-μr/r) and Coulomb’s potential (1/r) are modeled a... 详细信息

For a point charge between two grounded conductor planes forming a 60° angle, the potential and electric field generated by point charge for Yukawa’s potential (e-μrsup>/rspan>) and Coulomb’s potential (1/r) are modeled and simulated. The expression for the potential that generalizes the cases discussed in lópez-Mariñspan>o, M. and Trujillo Caballero, J. (2017) Point Charges and Conducting Planes for Yukawa’s Potential and Coulomb’s Potential. Journal of Electromagnetic Analysis and Applications, 9, 135-146. ref="https://***/10.4236/jemaa.2017.910012" target="_blank">https://***/10.4236/jemaa.2017.910012 is presented. Graphs for the potential and electric field for both cases are showed using Maple, that of Coulomb and that of Yukawa for different values of μ . The purpose of this work is to offer students a practical guide for problem analysis of electrostatics using Maple’s capabilities as a computational tool.

关键词： Yukawa’s Potential Coulomb’s Potential Method of Images

Chebyshev multidomain pseudospectral method to solve cardiac wave equations with rotational anisotropy

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International Journal of Modeling, simulation, and scientific Computing 2018年第4期9卷 58-82页

作者： Jairo rodrıguez-Padilla Daniel olmos-liceaga departamento de Matematicas Universidad de sonora.Blvd.rosales y luis Encinas s/N Col CentroC.P.83000HermosilloSonoraMexico

The implementation of numerical methods to solve and study equations for cardiac wave propagation in realistic geometries is very costly,in terms of computational *** aim of this work is to show the improvement that can be obtained with Chebyshev polynomials-based methods over the classical finite difference schemes to obtain numerical solutions of cardiac *** this end,we present a Chebyshev multidomain(CMD)Pseudospectral method to solve a simple two variable cardiac models on threedimensional anisotropic media and we show the usefulness of the method over the traditional finite differences scheme widely used in the literature.

关键词： Chebyshev-pseudospectral cardiac models anisotropic media.

Inference for a truncated positive normal distribution

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 163-176页

作者： Hector J.Gomez Neveka M.olmos Hector Varela Heleno Bolfarine departamento de Ciencias Matematicas y Ffsicas Facultad de IngenierlaUniversidad Catolica de TemucoTemucoChile departamento de Matematicas Facultad de Ciencias BasicasUniversidad de AntofagastaAntofagastaChile departamento de Estatfstica IMEUniversidade de Sao PauloSao PauloBrazil

The main object of this paper is to study an extension of the half normal distribution defined by adding a positive truncation to it. The new model is more flexible than the half-normal distribution and contains the half normal distribution as a special case. Properties of this distribution, such as moments, hazard function and entropy are studied and parameters estimation is dealt with by using inoinents and inaxiinuin likelihood. A real data application indicates good fit performance of the new model when compared to other competitors in litera- tures.

关键词： half-normal distribution maximum likelihood truncation

sintering study of Ti6Al4V powders with different particle sizes and their mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1389-1401页

作者： Joséluis Cabezas-Villa Josélemus-ruiz Didier Bouvard Omar Jiménez Héctor Javier Vergara-Hernández luis olmos University Michoacana of san Nicolás of Hidalgo IIMMMorelia 58060México University Grenoble Alpes CNRSSIMaPGrenoble 38000France University of Guadalajara Departamento de Ingeniería de ProyectosZapopan 45100México National Technological Institute of Mexico I.T.MoreliaMorelia 58120México University Michoacana of san Nicolás of Hidalgo INICITMorelia 58060México

Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 V powders.

关键词： Ti6Al4V powders dilatometry microhardness sintering kinetics compression failure behavior

Wear modes in open porosity titanium matrix composites with TiC addition processed by spark plasma sintering

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Transactions of Nonferrous Metals society of China 2019年第8期29卷 1653-1664页

作者： I. FAríAs l. olmos O. JIMéNEZ M. FlOrEs A. BrAEM J. VlEUGEls departamento de Ingeniería de Proyectos Universidad de Guadalajara 45100 Zapopan Jalisco México Instituto de Investigaciones en Ciencias de la Tierra - INICIT Universidad Michoacana de San Nicolás de Hidalgo 58060 Morelia Michoacán México KU leuven department of Materials Engineering Kasteelpark Arenberg 44 B-3001 Heverlee Belgium

This work focused on the influence of TiC reinforcing particles on the tribological properties of titanium matrix composites(TMCs)with open porosity,processed by spark plasma sintering(sPs).Materials composed of an equimolar mixture of Ti and TiH2 with 0,3,10 and 30 vol.% of TiC were sintered at 850 ℃.Nanoindentation and wear tests were carried out to assess the nanohardness and the wear resistance in a tribometer with a reciprocating sliding ball-on-flat *** showed a nanohardness increment from 5 to 14 GPa with increasing TiC *** coefficient of friction(CoF)showed a minimum of 0.2 for 10% TiC grade,which also showed the lowest wear *** the low TiC content sample,adhesive wear with severe plastic deformation was ***,medium content TiC sample showed a mechanical mixed layer(MMl),whereas high TiC content composite showed abrasive as the main wear *** conclusion,the wear mechanisms,CoFs and wear volume changed with TiC content.

关键词： porous titanium spark plasma sintering wear titanium matrix composites

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Neural regeneration research 2019年第9期14卷 1544-1555页

作者： laia Farras-Permanyer Nuria Mancho-Fora Marc Montala-Flaquer David Bartres-Faz lidia Vaque-Alcazar Maribel Pero-Cebollero Joan Guardia-olmos Quantitative Psychology section Faculty of PsychologyUniversity of BarcelonaBarcelonaSpain department of Medicine Faculty of Medicine and Healthy SciencesUniversity of BarcelonaBarcelonaSpain Institute of Neuroscience UB Institute of Complex SystemsUniversity of BarcelonaBarcelonaSpain Institut d’Investigacions Biomediques August Pi i sunyer BarcelonaSpain

Age-related changes in the brain connectivity of healthy older adults have been widely studied in recent years,with some differences in the obtained *** of these studies showed decreases in general functional connectivity,but they also found increases in some particular regions and ***,these studies compared young individuals with older subjects,but few studies compared different age groups only in older *** purpose of this study is to analyze whole-brain functional connectivity in healthy older adult groups and its network characteristics through functional segregation.A total of 114 individuals,48 to 89 years old,were scanned using resting-state functional magnetic resonance imaging in a resting state paradigm and were divided into six different age groups(rs old).A partial correlation analysis,a pooled correlation analysis and a study of 3-cycle regions with prominent connectivity were *** results showed progressive diminution in the functional connectivity among different age groups and this was particularly pronounced between 75 and 79 years *** oldest group(≥80 years old)showed a slight increase in functional connectivity compared to the other *** occurred possibly because of compensatory mechanism in brain *** study provides information on the brain functional characteristics of every age group,with more specific information on the functional progressive decline,and supplies methodological tools to study functional connectivity *** for the study was obtained from the ethics committee of the Comision de Bioetica de la Universidad de Barcelona(approval ***2012-38257)on June 5,2012,and from the ethics committee of the Barcelona’s Hospital Clinic(approval No.2009-5306 and 2011-6604)on October 22,2009 and April 7,2011 respectively.

关键词： brain connectivity resting state default mode network aging healthy functional connectivity resting state network age groups

design and characterization of Ti6Al4V/20CoCrMo−highly porous Ti6Al4V biomedical bilayer processed by powder metallurgy

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Transactions of Nonferrous Metals society of China 2021年第1期31卷 178-192页

作者： E.MIHAlCEA H.J.VErGArA-HErNÁNdeZ O.JIMENEZ l.olmos J.CHÁVEZ D.ArTEAGA División de Estudios de Posgrado e Investigación Tecnológico Nacional de México/ITMoreliaAv.Tecnológico#1500Colonia Lomas de SantiaguitoMoreliaC.P.58120México Universidad de Guadalajara DIPJoséGuadalupe Zuno#48Los BelenesZapopanC.P.45100México INICIT Universidad Michoacana de San Nicolás de HidalgoFco.J.Mujica S/NMoreliaC.P.58060México departamento de Ingeniería Mecánica Eléctrica CUCEIUniversidad de GuadalajaraBlvd.Marcelino García Barragán 1421OlímpicaC.P.44430 GuadalajaraJaliscoMéxico Centro de Geociencias Universidad Nacional Autónoma de MéxicoBlvd.Juriquilla No.3001Querétaro 76230México

The aim of this work was to develop a Ti6Al4V/20CoCrMo−highly porous Ti6Al4V bilayer for biomedical *** powder metallurgy technique,with semi-solid state sintering as consolidation step,was employed to fabricate samples with a compact top layer and a porous bottom layer to better mimic natural *** densification behavior of the bilayer specimen was studied by dilatometry and the resulting microstructure was observed by scan electron microscopy(sEM)and computed microtomography(CMT),while the mechanical properties and corrosion resistance were evaluated by compression and potentiodynamic tests,*** results indicate that bilayer samples without cracks were obtained at the interface which has no negative impact on the *** values of the highly porous layer were in the lower range of those of human *** compression behavior is dictated by the highly porous Ti6Al4V ***,the corrosion resistance of Ti6Al4V/20CoCrMo is better than that of Ti6Al4V,which improves the performance of the bilayer *** work provides an insight into the important aspects of a bilayer fabrication by powder metallurgy and properties of Ti6Al4V/20CoCrMo−highly porous Ti6Al4V structure,which can potentially benefit the production of customized implants with improved wear performance and increased in vivo lifetime.

关键词： bilayer structure composites porosity sintering permeability compression behavior corrosion

Constrained sintering and wear properties of Cu-WC composite coatings

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Transactions of Nonferrous Metals society of China 2017年第10期27卷 2214-2224页

作者： J.l.CABEZAs-VIllA l.olmos H.J.VErGArA-HErNáNdeZ O.JIMéNEZ P.GArNICA D.BOUVArD M.FlOrEs División de Estudios de Posgrado e Investigación TecNM/Instituto Tecnológico de MoreliaAv. Tecnológico #1500 Colonia Lomas de Santiaguito Morelia Michoacán C. P. 58120 México INICIT Universidad Michoacana de San Nicolás de HidalgoFco. J. Mujica S/N Morelia Michoacán C. P. 58060 México Universidad de Guadalajara Departamento de Ingeniería de ProyectosJosé Guadalupe Zuno # 48 Los Belenes Zapopan Jalisco C. P. 45100 México Univ. Grenoble Alpes CNRS SIMaP 38000 Grenoble France

Coatings of metal matrix composites(Cu?WC)were fabricated by solid-state *** reinforcing particles indifferent quantities from5%up to30%(volume fraction)were mixed with Cu *** mixing,the powders were poured ontothe surface of copper *** was carried out at1000°C under a reducing atmosphere in a vertical *** was affected by both rigid substrates and WC particles which retarded the radial and axial densification of ***,the coatings were strongly attached to the substrate,and WC particles were randomly distributed within the *** addition ofthe reinforcing particles enhanced the microhardness and reduced the volume loss in wear tests to1/17compared to the *** predominant wear mechanism was identified as abrasion at a load of5N.20%WC(volume fraction)reinforcingparticles led to the maximum values of properties for the composite coating.

关键词： constrained sintering dilatometry dry sliding wear microhardness metal matrix composites coating