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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 and simulated. The expression for the potential that generalizes the cases discussed in lópez-mariño, 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. lank">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

Holographic bottom-up approach to Σ baryons

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Chinese Physics C 2025年第1期49卷 95-104页

作者： Xi Guo miguel angel Martin Contreras Xun Chen Dong Xiang School of Nuclear Science and Technology University of South ChinaHengyang 421000China

In this study,we discuss the description of neutral Σ baryons with I(J^(P))=1(1/2^(+))and I(J^(P))=1(3/2^(+))using two bottom-up approaches:the deformed background and static dilaton *** both models,we consider a non-linear Regge trajectory extension motivated by the strange nature of Σ *** find that both models describe these systems with an RMS error smaller than 10%.We also perform a configurational entropy calculation in both models to discuss hadronic stability.

关键词： baryon spectroscopy AdS/QCD holographic QCD

Population structure and range expansion:the case of the invasive gastropod Cyclope neritea in northwest Iberian Peninsula

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Integrative Zoology 2012年第3期7卷 286-298页

作者： lucía CoUCEIRo lúa lÓpez Josémiguel RUIZ Rodolfo BARREIRo Department of Ecology College of ScienceUniversity of A CoruñaA CoruñaSpain

Biotic invasions have a reputation for unpredictable ***,we report how slight changes in human activity responsible for the introduction and range expansion of a non-native mollusk have led to detectable differences in the genetics of the *** neritea is a non-predatory gastropod introduced to 2 areas of the European Atlantic:the northwest Iberian Peninsula(NWIP)and the French Atlantic coast(FAC).Shellfish seabed farming is intense in both areas but focuses on different commercial *** mitochondrial gene sequences,the lower genetic diversity recorded along the NWIP suggests a more homogeneous range of source populations than in the *** FAC,genetic diversity and haplotype composition in the NWIP correlate with the date of first occurrence of *** at each site rather than with geographical *** this pattern evokes the genetic signature expected under a serial-founder colonization model from a single initial enclave,a comparison with samples from potential source populations suggests that the NWIP probably experienced several independent *** jump dispersal pattern of *** in the NWIP,together with the observation that populations established in the same year are genetically undifferentiated,point to human transport as the most plausible explanation for the current range *** evidence for human-mediated dispersal,*** managed to develop a seemingly non-random genetic pattern in the *** is suggested that caution must be exerted when interpreting genetic patterns in invaders.

关键词： alien species Cyclope neritea cytochrome oxidase I genetic geographic pattern population structure

First occurrence of Paragordius varius in Different Species of Acrididae in Irapuato, Guanajuato, Mexico

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Advances in Entomology 2025年第1期13卷 120-125页

作者： Manuel Dario Salas-Araiza Ilse Alejandra Huerta-Arredondo Rafael Guzmán-Mendoza Itzel Berenice Aguilar-Campos Daniela de Jesús Bustos-Gallaga miguel angel Rocha-García David Isaías Rodríguez-Vázquez Agronomy Department Life Sciences Division University of Guanajuato Irapuato Mexico

Acridid populations have increased significantly in recent years, causing damage to crops. Having biocontrol tools is important as it will help reduce the use of insecticides. This study reports the presence of Paragordius varius in grasshoppers for the first time in Irapuato, Guanajuato, Mexico. Samples were taken from the grass around a water pond. A total of 1,225 grasshoppers were dissected to observe the presence of the worm. Seven species of grasshoppers were identified, with the most abundant species being Melanoplus differentialis. The parasitoid Paragordius varius, a nematomorph, parasitized male M. differentialis in greater numbers. This work is the first record of this parasitoid in Mexico and contributes to the knowledge of the biological control of acridids in Mexico.

关键词： Grasshoppers Paragordius varius Parasitism Nematomorph Biological Control

Crosslinking degree variations enable programming and controlling soft fracture via sideways cracking

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npj Computational Materials 2024年第1期10卷 215-230页

作者： miguel angel Moreno-Mateos Paul Steinmann Institute of Applied Mechanics Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr.591058 ErlangenGermany Glasgow Computational Engineering Centre School of EngineeringUniversity of GlasgowGlasgowG128QQUnited Kingdom

large deformations of soft materials are customarily associated with strong constitutive and geometrical nonlinearities that originate new modes of *** isotropic materials can develop strong fracture anisotropy,which manifests as modifications of the crack *** cracking occurs when the crack deviates to propagate in the loading direction,rather than perpendicular to *** fracture mode results from higher resistance to propagation perpendicular to the principal stretch *** has been argued that such fracture anisotropy is related to deformation-induced anisotropy resulting from the microstructural stretching of polymer chains and,in strain-crystallizing elastomers,strain-induced crystallization ***,the precise variation of the fracture behavior with the degree of crosslinking remains to be *** experiments and computational simulations,here we show that the tendency of a crack to propagate sideways in the two component Elastosil P7670 increaseswith the degree of *** explore the mixing ratio for the synthesis of the elastomer that establishes the transition from forward to sideways *** assist the investigations,we construct a novel phase-field model for fracture where the critical energy release rate is directly related to the crosslinking *** results demonstrate that fracture anisotropy can be modulated during the synthesis of the ***,we propose a roadmap with composite soft structures with low and highly crosslinked phases that allow for control over fracture,arresting and/or directing the *** smart combination of the phases enables soft structures with enhanced fracture tolerance and reduced *** extending our computational framework as a virtual testbed,we capture the fracture performance of the composite samples and enable predictions based on more intricate composite unit ***,our work offers promising avenues for enhancing the fracture t

关键词： fracture cracking crack

Role of gene polymorphisms in gastric cancer and its precursor lesions:Current knowledge and perspectives in latin American countries

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World Journal of Gastroenterology 2014年第16期20卷 4503-4515页

作者： miguel angel Chiurillo laboratorio de Genética Molecular "Dr.Jorge Yunis-Turbay" Decanato de Ciencias de la SaludUniversidad Centroccidental Lisandro AlvaradoBarquisimeto 3001Venezuela

latin America shows one of the highest incidence rates of gastric cancer in the world,with variations in mortality rates among nations or even within countries belonging to this *** cancer is the result of a multifactorial complex process,for which a multistep model of carcinogenesis is currently *** to the infection with Helicobacter pylori,that plays a major role,environmental factors as well as genetic susceptibility factors are significant players at different stages in the gastric cancer *** differences in population origin,demographic structure,socio-economic development,and the impact of globalization lifestyles experienced in latin America in the last decades,all together offer opportunities for studying in this context the influence of genetic polymorphisms in the susceptibility to gastric *** aim of this article is to discuss current trends on gastric cancer in latin American countries and to review the available published information about studies of association of gene polymorphisms involved in gastric cancer susceptibility from this region of the world.A total of 40 genes or genomic regions and69 genetic variants,58%representing markers involved in inflammatory response,have been used in a number of studies in which predominates a low number of individuals(cases and controls)*** of Il-1B(-511 C/T,14 studies;-31 T/C,10 studies)and Il-1RN(variable number of tandem repeats,17 studies)are the most represented ones in the reviewed *** genetic variants recently evaluated in large metaanalyses and associated with gastric cancer risk were also analyzed in a few studies[e.g.,prostate stem cell antigen(PSCA),CDH1,Survivin].Further and better analysis centered in gene polymorphisms linked to other covariates,epidemiological studies and the information provided by meta-analyses and genome-wide association studies should help to improve our understanding of gastric cancer etiology in order to d

关键词： latin America Gastric cancer Precancerous lesions Gene polymorphisms Single nucleotide polymorphisms

Successful treatment with hysteroscopy for infertility due to isthmocele and hydrometra secondary to cesarean section: A case report

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World Journal of Clinical Cases 2019年第6期7卷 753-758页

作者： luis Pablo lópez Rivero miguel Jaimes Felipe Camargo Esther lópez-Bayghen Instituto de Infertilidad y Genética México SC Departamento de Toxicología Centro de Investigación de Estudios

BACKGRoUND An isthmocele is a scar defect in the uterine wall due to a cesarean section. Its prevalence is unknown,but it has been associated with secondary ***,we present a case where the patient suffered from an isthmocele that was associated with persistent hydrometra,which developed during in vitro *** SUMMARY The patient underwent hysteroscopic surgery,which successfully resolved the isthmocele as well as the hydrometra. Afterward,two high-quality,euploid embryos,determined by morphological assessment and pre-implantation genetic diagnostic testing,were transferred. This resulted in uterine pregnancy,as determined byserum β-human chorionic gonadotropin levels on day 14(180 m U/ml) and ultrasound-confirmed presence of a gestational sac with a positive embryocardia at week 6. The pregnancy reached 36 wk without any complications,and the product was born in good health. We report a successful isthmocele treatment in a patient with secondary infertility,in which the isthmocele was the cause of persistent *** Hydrometra caused by secondary cesarean is an infertility factor,which can be corrected by hysteroscopy plus ablation of the isthmocele.

关键词： In vitro fertilization Isthmocele Hydrometra Case report

Software Project Effort Estimation Based on Multiple Parametric Models Generated Through Data Clustering

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Journal of Computer Science & Technology 2007年第3期22卷 371-378页

作者： Juan J.Cuadrado Gallego Daniel Rodríguez miguel angel Sicilia miguel Garre Rubio angel García Crespo Department of Computer Science The University of Alcalá AlcaláSpain Department of Computer Science Carlos Ⅲ University.Madrid Spain

Parametric software effort estimation models usually consists of only a single mathematical relationship. With the advent of software repositories containing data from heterogeneous projects, these types of models suffer from poor adjustment and predictive accuracy. one possible way to alleviate this problem is the use of a set of mathematical equations obtained through dividing of the historical project datasets according to different parameters into subdatasets called partitions. In turn, partitions are divided into clusters that serve as a tool for more accurate models. In this paper, we describe the process, tool and results of such approach through a case study using a publicly available repository, ISBSG. Results suggest the adequacy of the technique as an extension of existing single-expression models without making the estimation process much more complex that uses a single estimation model. A tool to support the process is also presented. Keywords software engineering, software measurement, effort estimation, clustering

关键词： software engineering software measurement effort estimation clustering

Prevalence of the terrain reversal effect in satellite imagery

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International Journal of Digital Earth 2015年第8期8卷 640-655页

作者： miguel-angel Bernabé-Poveda Arzu Çöltekin Universidad de las Fuerzas Armadas–ESPE Departamento de Ciencias de la Tierra y de la ConstrucciónSangolquíPichinchaEcuador Geographic Information Visualization and Analysis Group Department of GeographyUniversity of ZurichSwitzerland

The terrain reversal effect is a perceptual phenomenon which causes an illusion in various 3D geographic visualizations where landforms appear inverted,*** perceive valleys as ridges and vice *** that such displays are important for spatio-visual analysis,this illusion can lead to critical mistakes in interpreting the ***,it is currently undocumented how commonly this effect is *** this paper,we study the prevalence of the terrain reversal effect in satellite imagery through a two-stage online user *** experiment was conducted with the participation of a diverse and relatively large population(n=535).Participants were asked to identify landforms(valley or ridge?)or judge a 3D spatial relationship(is A higher than B?).When the images were rotated by 180°,the results were *** a control task with‘illusion-free’original images,people were successful in identifying landforms,yet a very strong illusion occurred when these images were rotated 180°.our findings demonstrate that the illusion is acutely present;thus,we need a better understanding of the problem and its ***,the results caution us that in an interactive environment where people can rotate the display,we might be introducing a severe perceptual problem.

关键词： terrain reversal relief inversion false topographic perception phenomenon photo interpretation visual illusion user study

Whole-genome amplification/preimplantation genetic testing for propionic acidemia of successful pregnancy in an obligate carrier Mexican couple:A case report

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World Journal of Clinical Cases 2021年第29期9卷 8797-8803页

作者： Adina Neumann miguel angel Alcantara-ortigoza Ariadna González-del angel Nestor Alejandro Zarate Díaz Javier Sam Santana leonardo M Porchia Esther lópez-Bayghen laboratorio de Investigación y Diagnóstico Molecular IngenesMexico City 05320Mexico laboratorio de Biología Molecular Subdirección de Investigación MédicaInstituto Nacional de PediatríaMexico City 04530Mexico DNA-GEN S.C.Centro de Alta Especialidad en Genética Humana Mexico City 14070Mexico Investigación Clínica IngenesPuebla 72820Mexico Departamento de Toxicología Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMexico City 07360Mexico

BACKGRoUND Identifying a potential single monogenetic disorder in healthy couples is costly due to the Assisted Reproduction facilities'current methodology for screening,which focuses on the detecting multiple genetic disorders at ***,we report the successful application of a low-cost and fast preimplantation genetic testing for monogenic/single gene defects(PGT-M)approach for detecting propionic acidemia(PA)in embryos obtained from a confirmed heterozygous propionyl-CoA carboxylase alpha subunit(PCCA)*** SUMMARY A fertile 32-years old Mexican couple with denied consanguinity sought antenatal genetic *** were suspected obligate PA carriers due to a previous deceased PA male newborn with an unknown PCCA/propionyl-CoA carboxylase beta subunit(PCCB)***-Generation Sequencing revealed a heterozygous genotype for a pathogenic PCCA variant(c.2041-1G>T,ClinVar:RCV-000802701.1;dbSNP:rs1367867218)in both *** couple requested in vitro fertilization(IVF)and PGT-M for *** IVF,12 oocytes were collected and fertilized,of which two resulted in high-quality *** biopsies and Whole Genome Amplification by a fragmentation/amplification-based method were performed and revealed that the two embryos were *** polymerase chain reaction and further Sanger sequencing of the exon-intron borders revealed a wild-type PCCA male embryo and a heterozygous c.2041-1G>T female *** embryos were transferred,resulting in a clinical pregnancy and the delivery of a healthy male newborn(38 wk,weight:4080 g,length:49 cm,APGAR 9/9).The absence of PA was confirmed by expanded newborn *** We show that using PGT-M with Whole Genome Amplification templates,coupled with IVF,can reduce the transmission of a pathogenic variant of the PCCA gene.

关键词： Propionic acidemia Autosomal recessive Propionyl-CoA carboxylase alpha subunit(PCCA)gene Preimplantation genetic testing Next-generation sequencing Embryo transfer