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Comprehensive Analysis of Pan-African Mitochondrial DNA Variation Provides New Insights into Continental Variation and Demography

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Journal of Genetics and Genomics 2016年第3期43卷 133-143页

作者： Maria Cerezo Leonor Gusmao Viktor Cerny Nabeel Uddin Denise Syndercombe-Court Alberto Gdmez-Carballa Tanja Gobel Peter M. Schneider antonio Salas Unidade de Xenetica Departamento de Anatomia Patoloxica e Ciencias Forenses Instituto de Medicina Legal Facultade de Medicina Universidade de Santiago de Compostela Galicia 15782 Spain The Wellcome Trust Sanger Institute Hinxton CBIO 1SA UK DNA Diagnostic Laboratory Institute of Biology State University of Rio de Janeiro Rio de Janeiro 20550-900 Brazil IPATIMUP Institute of Molecular Pathology and Immunology of the University of Porto Porto 4200-465 Portugal Archaeogenetics Laboratory Institute of Archaeology of the Academy of Sciences of the Czech Republic Prague 118-01 Czech Republic Faculty of Life Sciences and Medicine King's College London London SE1 9NH UK Barts and The London School of Medicine and Dentistry Blizard Institute London E1 2AT UK Institute of Legal Medicine Medical Faculty University of Cologne Cologne D-50823 Germany

Africa is the cradle of all human beings, and although it has been the focus of a number of genetic studies, there are many questions that remain unresolved. We have performed one of the largest and most comprehensive meta-analyses of mitochondrial DNA （mtDNA） lineages carried out in the African continent to date. We generated high-throughput mtDNA single nucleotide polymorphism （SNP） data （230 SNPs） from 2024 Africans, where more than 500 of them were additionally genotyped for the control region. These data were analyzed together with over 12,700 control region profiles collected from the literature, representing more than 300 population samples from Africa. Insights into the African homeland of humans are discussed. Phylogeographic patterns for the African continent are shown at a high phylogeographic resolution as well as at the population and regional levels. The deepest branch of the mtDNA tree, haplogroup L0, shows the highest sub-haplogroup diversity in Southeast and East Africa, suggesting this region as the homeland for modem humans. Several demographic estimates point to the coast as a facilitator of human migration in Africa, but the data indicate complex patterns, perhaps mirroring the effect of recent continental-scaled demographic events in re-shaping African mtDNA variability.

关键词： mtDNA Haplotype Haplogroup SNP MALDI-TOF

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Tree growth is more limited by drought in rear-edge forests most of the times

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Forest Ecosystems 2021年第2期8卷 330-344页

作者： J.Julio Camarero antonio Gazol Gabriel Sangüesa-Barreda Marta Vergarechea Raquel Alfaro-Sánchez Nicolás Cattaneo Sergio M.Vicente-Serrano Instituto Pirenaico de Ecología(IPE-CSIC) Avda.Montañana 1005E-50192 ZaragozaSpain Ei FAB-iu FOR University of ValladolidCampus Duques de SoriaE-42004 SoriaSpain NIBIO Norwegian Institute of Bioeconomy ResearchPostboks 155NO-1431ÅsNorway Department of Biology Wilfrid Laurier UniversityN2L 3C575 Univ.Avenue WWaterlooOntarioCanada

Background:Equatorward,rear-edge tree populations are natural monitors to estimate species vulnerability to climate *** to biogeographical theory,exposition to drought events increases with increasing aridity towards the equator and the growth of southern tree populations will be more vulnerable to drought than in central ***,the ecological and biogeographical margins can mismatch due to the impact of ecological factors(topography,soils)or tree-species acclimation that can blur large-scale geographical imprints in trees responses to drought making northern populations more drought ***:We tested these ideas in six tree species,three angiosperms(Fagus sylvatica,Quercus robur,Quercus petraea)and three gymnosperms(Abies alba,Pinus sylvestris and Pinus uncinata)by comparing rear-edge tree populations subjected to different degrees of *** used dendrochronology to compare the radial-growth patterns of these species in northern,intermediate,and southern tree populations at the continental rear *** and conclusions:We found marked variations in growth variability between species with coherent patterns of stronger drought signals in the tree-ring series of the southern populations of ***,***,and *** was also observed in species from cool-wet sites(*** and ***),despite their limited responsiveness to ***,in the case of *** the intermediate population showed the strongest relationship to *** drought-sensitive species as *** and ***,southern populations presented more variable growth which was enhanced by cool-wet conditions from late spring to *** found a trend of enhanced vulnerability to drought in these two *** response of tree growth to drought has a marked biogeographical component characterized by increased drought sensitivity in southern populations even within the species distribution rear ***,the relationship

关键词： Climate change Dendroecology Latitudinal gradient Mediterranean forests Standardized evapotranspiration precipitation index(SPEI)

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Ectopic lignification in primary cellulose-deficient cell walls of maize cell suspension cultures

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Journal of Integrative Plant Biology 2015年第4期57卷 357-372页

作者： Hugo Mélida Asier Largo-Gosens Esther Novo-Uzal Rogelio Santiago Federico Pomar Pedro García Penélope García-Angulo José Luis Acebes Jesús álvarez antonio Encina Plant Physiology Laboratory Faculty of Biological and Environmental SciencesUniversity of León Centre for Plant Biotechnology and Genomics (CBGP) Politechnical University of Madrid Department of Plant Biology University of Murcia Plant Biology and Soil Sciences Department Faculty of BiologyUniversity of Vigo Environmental Agrobiology Soil and Plant Quality (University of Vigo)Associated Unit to Biological Mission of Galicia (CSIC) Department of Animal Biology Plant Biology and EcologyUniversity of A Coru?a Department of Molecular Biology(área de Genética) Faculty of Biological and Environmental SciencesUniversity of León

Maize （Zea mays L.） suspension-cultured cells with up to 7o% less cellulose were obtained by stepwise habituation to dichlobenil （DCB）, a cellulose biosynthesis inhibitor. Cellulose deficiency was accompanied by marked changes in cell wall matrix polysaccharides and phenolics as revealed by Fourier transform infrared （FTIR） spectroscopy. Cell wall compositional analysis indicated that the cellulosedeficient cell walls showed an enhancement of highly branched and cross-linked arabinoxylans, as well as an increased content in ferulic acid, diferulates and p-coumaric acid, and the presence of a polymer that stained positive for phloroglucinol. In accordance with this, cellulose-deficient cell walls showed a fivefold increase in Klason-type lignin. Thioacidolysis/GC-MS analysis of cellulose-deficient cell walls indicated the presence of a lignin-like polymer with a Syringyl/Guaiacyl ratio of 1.45, which differed from the sensu stricto stress-related lignin that arose in response to shortterm DCB-treatments. Gene expression analysis of these ceils indicated an overexpression of genes specific for the biosynthesis of monolignol units of lignin. A study of stress signaling pathways revealed an overexpression of some of the iasmonate signaling pathway genes, which might trigger ectopic lignification in response to cell wall integrity disruptions. In summary, the structural plasticity of primary cell walls is proven, since a lignification process is possible in response to cellulose impoverishment.

关键词： Cellulose DCB dichlobenil ectopic lignin maize

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Development and postnatal neurogenesis in the retina: a comparison between altricial and precocial bird species

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Neural Regeneration Research 2021年第1期16卷 16-20页

作者： Guadalupe Álvarez-Hernán José antonio de Mera-Rodríguez Yolanda Gañán Jorge Solana-Fajardo Gervasio Martín-Partido Joaquín Rodríguez-León Javier Francisco-Morcillo Área de Biología Celular Departamento de AnatomíaBiología Celular y ZoologíaFacultad de CienciasUniversidad de ExtremaduraBadajozSpain Área de Anatomía Humana Departamento de AnatomíaBiología Celular y ZoologíaFacultad de MedicinaUniversidad de ExtremaduraBadajozSpain Servicio de Oftalmología Complejo Hospitalario Universitario de BadajozBadajozSpain

The visual system is affected by neurodegenerative diseases caused by the degeneration of specific retinal neurons,the leading cause of irreversible blindness in *** vertebrate phylogeny,the retina has two kinds of specialized niches of constitutive neurogenesis:the retinal progenitors located in the circumferential marginal zone and Müller *** proliferative activity in the retinal progenitors located in the circumferential marginal zone in precocial birds such as the chicken,the commonest bird model used in developmental and regenerative studies,is very *** region adds only a few retinal cells to the peripheral edge of the retina during several months after hatching,but does not seem to be involved in retinal regeneration.Müller cells in the chicken retina are not proliferative under physiological conditions,but after acute damage some of them undergo a reprogramming event,dedifferentiating into retinal stem cells and generating new retinal ***,regenerative response after injury occurs with low efficiency in the precocial avian *** contrast,it has recently been shown that neurogenesis is intense in the retina of altricial birds at *** particular,abundant proliferative activity is detected both in the circumferential marginal zone and in the outer half of the inner nuclear ***,stem cell niches are very active in the retina of altricial *** more extensive research is needed to assess the potential of proliferating cells in the adult retina of altricial birds,it emerges as an attractive model for studying different aspects of neurogenesis and neural regeneration in vertebrates.

关键词： altricial birds circumferential marginal zone Müller glia postnatal neurogenesis precocial regeneration retinogenesis

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Induced Dipoles in Electromagnetic Media in Motion

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Journal of Electromagnetic Analysis and Applications 2018年第11期10卷 185-192页

作者： José-antonio-Eduardo Roa-Neri José-Luis Jiménez-Ramírez Ignacio Campos-Flores área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México México D. F. México

We present a non-relativistic approach to the equivalent polarization Peq=(1/c2)v×Meq, that appears in a magnetized medium in motion. We apply an analogous method to that used by Panofsky and Phillips to calculate the symmetric effect, the equivalent magnetization that appears in a polarized dielectric in motion, Meq=P×v,?This method is based on a particular expression of Maxwell’s equations and the application of the convective derivative. These authors argue, however, that the equivalent polarization can be obtained only with a relativistic approach. We show that with the same method, but with a different and equivalent expression of Maxwell’s equations, this effect can also be calculated. In this way both effects can be considered relativistic effects to first order in v/c.

关键词： Moving Media Polarized Dielectric Macroscopic Maxwell Equations Induction of Magnetic Dipoles

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A New Perspective of the Force on a Magnetizable Rod inside a Solenoid

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Journal of Electromagnetic Analysis and Applications 2018年第10期10卷 171-183页

作者： José-Luis Jiménez-Ramírez Ignacio Campos-Flores José-antonio-Eduardo Roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México México D. F. México área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México

We analyze the familiar effect of the pulling of a magnetizable rod by a magnetic field inside a solenoid. We find that the analogy with the pulling of a dielectric slab by a charged capacitor is not as direct as usually thought. Indeed, there are two possibilities to pursue the analogy, according to the correspondence used,?either E → B and D → H, or E?→ H and D?→ B. One of these results in an incorrect sign in the force, while the other gives the correct result. We avoid this ambiguity in the usual energy method applying a momentum balance equation derived from Maxwell’s equations. This method permits the calculation of the force with a volume integration of a force density, or with a surface integration of a stress tensor. An interpretation of our results establishes that the force acts at the interface and has its origin in Maxwell′s magnetic stresses at the medium-vacuum interface. This approach provides new insights and a new perspective of the origin of this force.

关键词： Force on a Rod in a Solenoid Magnetostatic Force Maxwell Momentum Balance Equation

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Electrostatic and Magnetostatic Forces That Arise from Electrostatic and Magnetostatic Pressures

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Journal of Electromagnetic Analysis and Applications 2019年第3期11卷 25-40页

作者： José-Luis Jiménez-Ramírez Ignacio Campos-Flores José-antonio-Eduardo Roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México CDMX México área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México

With the insight provided by a balance equation of electromagnetic momentum, we compare the force on a dielectric slab inside a capacitor with the force on a magnetizable rod inside a solenoid. We conclude that these forces are not exactly analogous, as usually thought. We present a device that is a proper analogy of the case of a dielectric slab inside a capacitor. Our analysis shows the significance of the electrostatic and magnetostatic pressures to the understanding of these effects and shows the conceptual differences between both cases.

关键词： Polarizable Electric and Magnetic Media Electric and Magnetic Pressures Electromagnetic Force Densities Macroscopic Maxwell Equations Balance Equations of Electromagnetic Momentum

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How Does Arise the Force on a Dielectric Slab in a Parallel Plate Capacitor?

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Journal of Electromagnetic Analysis and Applications 2018年第7期10卷 131-142页

作者： Ignacio Campos-Flores José-Luis Jiménez-Ramírez José-antonio-Eduardo Roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City Mexico rea de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco Mexico City Mexico

We address the problem of the force exerted on a dielectric slab partially introduced into a charged parallel plate capacitor. This elementary problem is usually solved calculating this force as the gradient of an energy and attributing its origin to the action of the fringing field outside the capacitor on the dipoles of the dielectric slab. By applying Maxwell’s theory of electromagnetic stresses, we show that this force acts at the interface dielectric-vacuum and originates from the action of these stresses. This approach permits to obtain the force as a volume integration of a force density, or as a surface integral of a stress tensor. This force density and the stress tensor are part of a momentum balance equation derived from Maxwell’s equations.

关键词： Classical Electromagnetism Maxwell Equations Electrostatics Maxwell Balance Equation Maxwell Stress Tensor

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Balance Equations of Electromagnetic Angular Momentum

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Journal of Electromagnetic Analysis and Applications 2017年第12期9卷 203-217页

作者： Ignacio Campos-Flores José Luis Jiménez-Ramírez José antonio Eduardo Roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City México área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco Mexico City México

We give theoretical foundation to torque densities proposed in the past, like the one used by Beth to study experimentally the action of circularly polarized radiation on a birefringent material, or that proposed by Mansuripur to resolve a seeming paradox concerning the Lorentz force law and relativity. Our results provide new insights into electromagnetic theory, since they provide a unified and general treatment of the balance of lineal and angular momentum that permits a better assessment of some torques. Thus in this work we extend the derivations we have made of balance equations for electromagnetic linear momentum to balance equations for electromagnetic angular momentum. These balance equations are derived from the macroscopic Maxwell equations by means of vector and tensor identities and from the different ways in which these equations are written in terms of fields E, D, B, and H, as well as polarizations P, and M. Therefore these balance equations are as sound as the macroscopic Maxwell equations, with the limitations of the constitutive relations.

关键词： Balance Equations Foundations of Electrodynamics Electromagnetic Angular Momentum Macroscopic Maxwell Equations Abraham-Minkowski Controversy

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Imported Mansonella perstans infection in Spain

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Infectious Diseases of Poverty 2020年第4期9卷 158-158页

作者： Sabino Puente Mar Lago Mercedes Subirats Ismael Sanz-Esteban Marta Arsuaga Belén Vicente Montserrat Alonso-Sardon Moncef Belhassen-Garcia antonio Muro Unidad de Medicina Tropical Servicio de Medicina InternaHospital La Paz-Carlos IIIMadridSpain Microbiología Hospital La Paz-Carlos IIIMadridSpain Facultad de Fisioterapia Universidad Europea de MadridMadridSpain Laboratorio de Inmunología Parasitaria y Molecular CIETUSIBSALFacultad de FarmaciaUniversidad de Salamanca37007SalamancaSpain Área de Medicina Preventiva y Salud Pública IBSALCIETUSUniversidad de SalamancaSalamancaSpain Servicio de Medicina Interna Sección de Enfermedades InfecciosasCAUSAIBSALCIETUSUniversidad de SalamancaPaseo San Vicente 58-18237007SalamancaSpain

Background Mansonella perstans infection can be considered one of the most neglected tropical infectious *** few studies have reported on the clinical picture caused by infection with this ***,our study was aimed to describe the clinical patterns and treatment of imported *** infection by migrants from *** The present study evaluated a large cohort of migrants who have been diagnosed,examined and treated for imported *** infection at a Spanish reference center(Hospital Carlos III Tropical Medicine Unit,Madrid,Spain)over a 19-year *** patients voluntarily attend the emergency unit or are referred from primary care or general hospitals in ***-square test was used to compare the association between categorical *** continuous variables were compared by Student’s t-test or the Mann–Whitney *** corresponding regression models were used for multivariate *** Five hundred three cases of migrants from tropical and subtropical areas with *** infection were *** hundred sixty-four patients were female(52.5%).The mean age(±SD)was 44.6±18.2 years(range:16–93 years).The mean time(±SD)between the arrival in Spain and the first consultation was 8.6±18.0 *** major origin of the patients was Equatorial Guinea(97.6%).Regarding the clinical picture,257 patients were asymptomatic(54.7%)and 228 were symptomatic(45.3%);190 patients had pruritus(37.8%),50(9.9%)had arthralgia,18 patients had Calabar-like swelling(3.6%),and 15(3%)had abdominal *** hundred forty-two(87.9%)migrants had hyper-IgE,and 340(67.6%)had *** hundred ninety-five patients had coinfections with other filarial nematodes(38.8%),and 308 migrants had only *** infection(61.2%).Four hundred thirty-seven cases(86.9%)had been treated with anti-filarial drugs;292 cases were treated with one anti-filarial drug,and 145 cases were treated with combined anti-filarial ***,20(4%)

关键词： Mansonellosis Mansonella perstans Clinical study Immigrant Imported diseases Spain

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