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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.

Child access prevention legislative language and pediatric firearm injury rates

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World Journal of Pediatric Surgery 2021年第4期4卷 1-6页

作者： Bradford James bertha Ben Khallouq Hubert Swana University of Central Florida College of Medicine OrlandoFloridaUSA Pediatric Diagnostic Lab Arnold Palmer Hospital for ChildrenOrlandoFloridaUSA Pediatric Urology Arnold Palmer Hospital for ChildrenOrlandoFloridaUSA

Backgroud Firearm injuries are a significant public health problem facing young people in the *** 2015,a total of 16878 people under 19 years old were injured or killed by *** reduce firearm injuries,29 states and Washington,DC have enacted child access prevention(CAP)*** legislation is intended to reduce the likelihood of a minor obtaining a weapon and subsequent injury or *** study evaluates the impact of CAP legislation based on language of the legislation,specifically it evaluates a relationship of the legal threshold of liability and the number of firearm injuries per capita of *** Data were collected from the Web-based Injury Statistics Query and Reporting System for patients less than 19 years of age who presented to emergency departments with firearm injuries in *** Giffords Law Center classification was used to group states into three categories(strong/weak/no CAP)based on CAP *** of firearm-related injury rates per capita were *** When controlling for population,states with CAP legislation had a 22%decrease in firearm injuries per capita compared with states without CAP *** with‘strong’CAP legislation had a 41%decrease in firearm injuries per capita compared with states with‘weak’or no CAP legislation when controlling for *** States with‘strong’CAP legislation had lower pediatric firearm injury rates per capita,but more complete data and further studies are needed to evaluate this relationship as well as other factors that may impact firearm injury rates.

关键词： injuries prevention firearm

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

A look into the past, present and future potential distributions of Talinopsis frutescens, a North American endemic lineage closely related to Cactaceae

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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

Role of platelets and breast cancer stem cells in metastasis

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World Journal of Stem Cells 2020年第11期12卷 1237-1254页

作者： Gretel Mendoza-Almanza Luis Burciaga-Hernandez Vilma Maldonado Jorge Melendez-Zajgla Jorge olmos CONACYT Universidad Autónoma de Zacatecas.Zacatecas 98060Mexico Maestría en Ciencias Biomédicas Universidad Autónoma de ZacatecasZacatecas 98160Mexico Laboratorio de Epigenética Instituto Nacional de Medicina GenómicaCiudad de México 14610Mexico Génómica funcional del cáncer Instituto Nacional de Medicina GenómicaCiudad de México 14610Mexico Biotecnología Marina Centro de Investigación Científica y de Estudios Superiores de EnsenadaEnsenada 22860Mexico

The high mortality rate of breast cancer is mainly caused by the metastatic ability of cancer cells,resistance to chemotherapy and radiotherapy,and tumor regression *** recent years,it has been shown that the presence of breast cancer stem cells is closely associated with the migration and metastatic ability of cancer cells,as well as with their resistance to chemotherapy and *** tumor microenvironment is one of the main molecular factors involved in cancer and metastatic processes development,in this sense it is interesting to study the role of platelets,one of the main communicator cells in the human body which are activated by the signals they receive from the microenvironment and can generate more than one *** can ingest and release RNA,proteins,cytokines and growth *** the platelets interact with the tumor microenvironment,they are called"tumor-educated platelets."Tumor-educated platelets transport material from the tumor microenvironment to sites adjacent to the tumor,thus helping to create microenvironments conducive for the development of primary and metastatic *** has been observed that the clone capable of carrying out the metastatic process is a cancer cell with stem cell *** stem cells go through a series of processes,including epithelial-mesenchymal transition,intravasation into blood vessels,movement through blood vessels,extravasation at the site of the establishment of a metastatic focus,and site ***-educated platelets support all these processes.

关键词： Breast cancer stem cells Platelets Metastasis Tumor microenvironment Epithelial-mesenchymal transition

Representative volume element of asphalt pavement for electromagnetic measurements

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Journal of Traffic and Transportation Engineering(English Edition) 2015年第1期2卷 30-39页

作者： Terhi Pellinen Eeva Huuskonen-Snicker Pekka Eskelinen Pablo olmos Martinez Department of Civil and Environmental Engineering Aalto University Department of Electrical Engineering and Automation Aalto University

The motivation for this study was to investigate the representative volume element （RVE） needed to correlate the nondestructive electromagnetic （EM） measurements with the con- ventional destructive asphalt pavement quality control measurements. A large pavement rehabilitation contract was used as the test site for the experiment. Pavement cores were drilled from the same locations where the stationary and continuous Ground Penetrating Radar （GPR） measurements were obtained. Laboratory measurements included testing the bulk density of cores using two methods, the surface-saturated dry method and determining bulk density by dimensions. Also, Vector Network Analyzer （VNA） and the through specimen transmission configuration were employed at microwave frequencies to measure the reference dielectric constant of cores using two different footprint areas and therefore vol- ume elements. The RVE for EM measurements turns out to be frequency dependent; therefore in addition to being dependent on asphalt mixture type and method of obtaining bulk density, it is dependent on the resolution of the EM method used. Then, although the average bulk property results agreed with theoretical formulations of higher core air void content giving a lower dielectric constant, for the individual cores there was no correlation for the VNA measurements because the volume element seizes deviated. Similarly, GPR technique was unable to capture the spatial variation of pavement air voids measured from the 150-mm drill cores. More research is needed to determine the usable RVE for asphalt.

关键词： Asphalt Dielectric constant Permittivity Vector Network Analyzer Bulk density

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

Glycosylation on proteins of the intestine and perimicrovillar membrane of Triatoma (Meccus) pallidipennis, under different feeding conditions

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Insect Science 2019年第5期26卷 796-808页

作者： Ana E.Gutierrez-Cabrera Wesley F.Zandberg Edgar Zenteno Mario H.Rodriguez bertha Espinoza Carl Lowenberger CONACyT-Centro de Investigacion Sobre Enfermedades Infecciosas Instituto Nacional de Salud PublicaCuernavacaMorelosMexico Department of Chemistry Simon Fraser UniversityBurnabyBCCanada Department of Chemistry The University of British Columbia OkanaganKelownaBCCanada Facultad de Medicina Departamento de BioquimicaUniversidad Nacional Autdmoma de Mexico Mexico CityDFMexico Centro de Investigacion Sobre Enfermedades Infecciosas Instituto Nacional de Salud PublicaCuernavaca MorelosMexico Departamento de Inmunologia Instituto de Investigaciones BiomedicasUniversidad Nacional Autonoma de Mexico Ciudad UniversitariaMexico CityDFMexico Department of Biological Sciences Simon Fraser UniversityBurnabyBCCanada

Trypanosoma cruzi,the causative agent of Chagas disease, interacts with molecules in the midgut of its insect vector to multiply and reach the infective stage. Many studies suggest that the parasite binds to midgut-specific glycans. We identified several glycoproteins expressed in the intestine and perimicrovillar membrane (PMM) of Triatoma (Meccus) pallidipennis under different feeding conditions. In order to assess changes in protein-linked glycans, we performed lectin and immunoblot analyses on glycoprotein extracts from these intestinal tissues using well-characterized lectins, and an antibody, which collectively recognize a wide range of different glycans epitopes. We observed that the amount and composition of proteins and glycoproteins associated with different glycans structures changed over time in the intestines and PMM under different physiological conditions. PMM extracts contained a wide variety of glycoproteins with different sugar residues, including abundant high-mannose and complex sialylated glycans. We propose that these molecules could be involved in the process of parasite-vector interactions.

关键词： feeding conditions glycoproteins lectins perimicrovillar membrane triatomine vector-parasite interactions

镰状细胞对内皮诱导一氧化氮的清除能力低下(英文)

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Acta Pharmacologica Sinica 2002年第11期23卷 9-15页

作者： Leopoldo olmos,Jean-Vivien MOMBOULI,Nathan WASSERSTRUM,Paul MVANHOUTTE Center for Experimental Therapeutics Baylor College of Medicine Houston TX 77030 USA University of Marien Ngouabi Brazzaville Republic of Congo Center for Experimental Therapeutics Baylor College of Medicine Houston TX 77030 USA lnstitut de Recherches Internationales Servier 92415 Courbevoie Cedex France

AIM: To assess the ability of sickle cells to interfere with the release or transfer of endothelium-derived relaxing factor (EDRF) in comparison to normal erythrocytes. METHODS: A perfusion-superfusion bioassay system was used a canine carotid artery with endothelium (donor of EDRF) and a ring of the same vessel without endothelium (detector) were separated by tubing resulting in a five second interval for transfer of EDRF from donor to detector. Changes in isometric tension were monitored in both the donor and the detector preparations. Release of EDRF, as determined by sustained relaxations during the contractions to phenylephrine, was induced by infusing acetylcho-line through the donor artery. RESULTS: Supervision with normal and sickle erythrocytes caused impairment of the endothelium-dependent relaxations in both detector and donor tissues. When infused through the transfer line, sickle cells were less potent than normal erythrocytes in inhibiting relaxation in the detector tissues. In contrast, i

关键词：镰状细胞贫血内皮血管平滑肌红细胞微循环一氧化氮