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On the Differential Polynomial of a Graph

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Acta mathematica Sinica,English Series 2019年第3期35卷 338-354页

作者： Ludwin A.BASILIO-HErNáNDEZ Walter CArBALLOSA Jesús LEA?OS josé m.sigarreta Unidad Académica de matemáticas Universidad Autónoma de Zacatecas Calzada Solidaridad entronque Paseo a la Bufa Department of mathematics and Statistics Florida International University Department of mathematics Miami Dade College Facultad de matemáticas Universidad Autónoma de Guerrero

We introduce the differential polynomial of a graph. The differential polynomial of a graph G of order n is the polynomial B(G; x) :=∑?(G)k=-nB_k(G) x^(n+k), where B_k(G) denotes the number of vertex subsets of G with differential equal to k. We state some properties of B(G;x) and its *** particular, we compute the differential polynomial for complete, empty, path, cycle, wheel and double star graphs. We also establish some relationships between B(G; x) and the differential polynomials of graphs which result by removing, adding, and subdividing an edge from G.

关键词： Graph polynomial differential of a graph

Integral representation Formulas related to the Lamé–Navier System

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Acta mathematica Sinica,English Series 2020年第12期36卷 1341-1356页

作者： ricardo ABrEU-BLAYA Juan BOrY-rEYES m.rcos Antonio-HErrEra-PELáEZ josé m.ría sigarreta-alm.ra Facultad de matemáticas Universidad Autónoma de GuerreroGuerreroMéxico Instituto Politécnico Nacional SEPI-ESImE-ZAC CD-MXMéxico

The paper provides integral representations for solutions to a certain first order partial differential equation natural arising in the factorization of the Lamé–Navier system with the help of Clifford analysis *** representations look like in spirit to the Borel–Pompeiu and Cauchy integral formulas both in three and higher dimensional setting.

关键词： Lamésystem Clifford analysis Dirac operator

Vegetation response To Soil And m.rphological Properties In An Arid region Alluvial Fan Landscape. Pre-Andes Of San Juan， Argentina

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Journal of Earth Science 2024年

作者： FLOrES Daniel Germán OCA?A raúl Emmanuel mELIáN Edgardo OrTEG Andrés ESPEr ANGILLIErI m.ría Yanina PITTALUGA m.ría Alejandra CIGEOBIO (CONICET-UNSJ) Av.josé I.de la roza y meglioli Gabinete de Geología Ambiental， INGEO， Universidad Nacional de San Juan， Av.josé I.de la roza y meglioli

The monte Desert is characterized by a great diversity of landforms created with fluvial， alluvial which the vegetation patterns are related to. The present work has the following objectives: 1: determine whether topographical attributes， surface characteristics， soil properties and vegetation patterns vary between alluvial landforms， and 2: define whether m.rphometric， soil and surface properties influence vegetation patterns along alluvial landscape. m.rphometric data were obtained by processing a 5 m digital elevation model. The coverage of rock fragments， fine sediments and mulch was quantified. Observations and descriptions of the soil profiles were restricted to the uppermost 50 cm. Vegetation properties were calculated using a Point Quadrat method. The relationship between variables was evaluated through multivariate statistical analysis. The main results show the presence of 45 plant species distributed in 19 families， where shrubs are dominant. The wind effect， topographic wetness and dissection of the landscape are limiting factors of diversity. The coverage of superficial rock fragments influence vegetation coverage through the distribution and availability of rainwater. Furtherm.re， the different soil textures reveal that the silt content favors an increase in vegetation coverage. The presence of V horizon could condition the installation and development of vegetation in the early stages of growth.

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Extensive pollen immigration and no evidence of disrupted mating patterns or reproduction in a highly fragmented holm oak stand

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Journal of Plant Ecology 2014年第4期7卷 384-395页

作者： Joaquín Ortego raúl Bonal Alberto muñoz josémiguel Aparicio Grupo de Investigación de la Biodiversidad Genética y Cultural Instituto de Investigación en Recursos Cinegéticos-IREC(CSICUCLMJCCM)Ronda de Toledo s/nE-13005 Ciudad RealSpain Departamento de Ecología Evolutiva Museo Nacional de Ciencias Naturales(CSIC)C/JoséGutiérrez Abascal 2E-28006 MadridSpain Departamento de Didáctica de las Ciencias Experimentales Facultad de EducaciónUniversidad Complutense de MadridC/Rector Royo Villanova s/nE-28040 MadridSpain Centre de recerca Ecològica i Aplicacions Forestals(CrEAF) Cerdanyola del VallèsE-08193 BarcelonaSpain

Aims Forest fragmentation and reduced tree population densities can poten-tially have negative impacts on mating patterns,offspring genetic diversity and reproductive *** aim of the present study is to test these hypotheses comparing an extremely fragmented,low tree density(~0.02 trees/ha)holm oak(Quercus ilex l.)stand from Central spain with a nearby high tree density stand(~50 trees/ha).methods We genotyped adult trees and seeds from the low-density stand(436 seeds from 15 families)and the high-density stand(404 seeds from 11 families)using nine microsatellite *** these data,we performed paternity analyses,determined pollen flow,mating patterns and pollen pool structure,and estimated progeny genetic diversity in both *** also studied seed set and production and performed a pollen supplementation experiment to determine whether reduced tree density has limited foreign pollen *** Findings We have found extensive pollen immigration(>75%)into the low tree density stand and monte Carlo simulations revealed that pollen moves larger distances than expected from null models of random *** patterns and differentiation of pollen pools were similar in the high-density stand and the low-density stand but we found higher inter-annual differentiation of pollen pools in the *** genetic diversity and self-fertilization rates did not dif-fer between the low-density stand and the high-density *** set rates were significantly lower in the low-density stand than in the high-density stand and experimental cross-pollen supplementation evidenced that foreign pollen availability is indeed a limiting factor in the ***,seed crops did not differ between the low-density stand and the high-density stand,indicating that limitation of foreign pollen is not likely to be of great concern in terms of reduced seed production and potential *** forest regeneration due to other ecological and human fac

关键词： forest fragmentation genetic diversity paternity analyses pollen dispersal pollen pool structure selfing tree density

Atmospheric-pressure dielectric barrier discharge generation by a full-bridge flying capacitor multilevel inverter

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Plasma Science and Technology 2017年第7期19卷 40-49页

作者： rosendo PE?A-EGUILUZ josé A LóPEZ-FErNáNDEZ Antonio m.rCADO-CABrEra Bethsabet JAramILLO-SIErra régulo LóPEZ-CALLEJAS Benjamín rODríGUEZ-méNDEZ raúl VALENCIA-ALVAraDO Allan A FLOrES-FUENTES Arturo E mU?OZ-CASTrO Plasma Physics Laboratory Instituto Nacional de Investigaciones Nucleares Tecnológico de Estudios Superiores de Tianguistenco Universidad Autónoma del Estado de méxico

A new configuration of a resonant full-bridge flying capacitor multicell inverter has been designed and constructed with the aim of achieving an extended output voltage frequency range with low harmonic distortion and reduced semiconductor commutation losses. This configuration was tested as a power supply for two different coaxial dielectric barrier discharge reactors, one of them employed for electric characterization and the other one for inorganic compound elimination in an aqueous solution. Two different gas mixtures, 90% Ar-10% 02 and 80% Ar-20% 02, were individually supplied during the experiments; the results showed a high- efficiency removal of meta-cresol （m-cresol） to the order of 98%, which was obtained by adding m.re oxygen to the plasma gas mixture.

关键词： plasma applications water pollution plasma sources power supply circuits electricdischarges

Diversity, Endemism and Conservation of Ferns(Polypodiales) in the mexican mountain Component

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Journal of mountain Science 2015年第4期12卷 891-904页

作者： SANGINéS-FraNCO Celia LUNA-VEGA Isolda CONTrEraS-mEDINA raúl ESPINOSA David TEJErO-DíEZ josé Daniel rIVAS Gerardo Laboratorio de Biogeografía y Sistemática Departamento de Biología Evolutiva Facultad de Ciencias Universidad Nacional Autónoma de México (UNAM) Escuela de Ciencias Universidad Autónoma "Benito Juárez" de Oaxaca (UABJO) Av.Universidad s/n Ex Hacienda de Cinco Se?ores Oaxaca de Juárez CP 68120 Oaxaca México Facultad de Estudios Superiores Zaragoza Unidad Multidisciplinaria de Investigación Experimental ZaragozaUniversidad Nacional Autónoma de México (UNAM) Carrera de Biología Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de México MéxicoAvenida de los Barrios Número 1 Colonia Los Reyes Iztacala Tlalnepantla CP 54090 Estado de México México Laboratorio de Biogeografía Acuática Departamento de Biología Comparada Facultad de Ciencias Universidad Nacional Autónoma de México (UNAM)

We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the mexican mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity *** data were obtained from several herbaria and specialized *** grid-cells appear to be important for fern species richness, as they contain 35 to 49 *** gridcells are located in the Sierra madre Oriental(SmO),Trans-mexican Volcanic Belt(TmVB) and the Sierra madre del Sur(SmS).mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TmVB and SmS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SmO, TmVB and *** richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SmO, the eastern portion of the TmVB and the northern part of the SmS, reflecting the high humidity existing on the mountain slopes facing the Gulf of *** important grid-cells recognized from.richness and endemism analyses coincide with mexican Natural Protected *** beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the mexican mountain *** the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization com.rising twomain areas: the mexican Transition Zone and the mexican Central *** play an important role in the mexican biodiversity and contributing to the beta diversity of mexico.

关键词： Biogeography Distributional patterns Leptosporangiate ferns mexico

Adverse hepatic reactions associated with calcium carbimide and disulfiram therapy: Is there still a role for these drugs?

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World Journal of Gastroenterology 2006年第31期12卷 5078-5080页

作者： Carmen Verge m Isabel Lucena Enrique López-Torres m josé Puche-García Enrique Fraga manuel rom.ro-Gomez raúl J Andrade Clinical Pharmacology ServiceVirgen de la Victoria University Hospital School of MedicineMálagaSpain Gastroenterology ServiceUniversity Hospital reina Sofia CórdobaSpain Gastroenterology ServiceUniversity Hospital Virgen de Valme SevillaSpain Liver UnitDepartment of Gastroenterology University HospitalMálagaSpain

Disulfiram and calcium carbimide are two alcohol deterrants widely used in alcoholism treatment, however, there exist great concerns over their safety. reports on hepatotoxicity, mainly related to disulfiram therapy, have been published. The hepatotoxic potential of calcium carbimide is less well characterized. Here, we describe four cases of liver damage related to this therapeutic group that were submitted to a registry of hepatotoxicity and point out the limitations that we face when prescribing these compounds. A reassessment of the role of these compounds in the management of alcohol dependence is clearly needed.

关键词： Calcium carbimide Disulfiram Hepatotoxicity

Em.ryo and Endosperm Phytochemicals from Polyem.ryonic maize Kernels and Their relationship with Seed Germination

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Phyton-International Journal of Experimental Botany 2022年第5期91卷 929-941页

作者： J.David García-Ortíz rebeca González-Centeno m.ría Alejandra Torres-Tapia J.A.Ascacio-Valdés joséEspinoza-Velázquez raúl rodríguez-Herrera Food research Department School of ChemistryAutonomous University of CoahuilaSaltillo25280México Plant Breeding Department Universidad Autonoma Agraria Antonio Narro(UAAAN)Saltillo25315México

Because of the growing worldwide demand for maize grain,new alternatives have been sought for breeding of this cereal,e.g.,development of polyem.ryonic varieties,which agronomic performance could positively impact the grain yield per unit area,and nutritional *** objectives of this study were to(1)determine the phytochemicals present in the em.ryo and endosperm of grain from maize families with high,low,and null polyem.ryony frequency,which were planted at different locations,and(2)state the relationship between these compounds and seed *** extracted phytochemicals from corn were identified by *** results showed that the genotype with the highest presence of phytochemicals was the brachytic population with high polyem.ryony called“BAP”,which also required less water during the germination *** number of phytochemicals in both em.ryo and endosperm tissues was not related to the sowing location where they came from or the type of *** number of different phytochemicals depended on the grain tissue from where they were *** chemical compounds found in the different maize tissues were related to the development of the plant,either in roots or nibs because these are mainly associated with the lignin synthesis.

关键词： Zea mays L HPLC-mS locations kernels phytochemicals

Effects of Finer Scale Soil Survey and Land-Use Classification on SWAT Hydrological modelling Accuracy in Data-Poor Study Areas

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Journal of Water resource and Protection 2022年第2期14卷 100-125页

作者： Verenice Escamilla-rivera Sergio Cortina-Villar raúl A. Vaca Duncan Golicher josé Arellano-monterrosas Jordi Honey-rosés Patagonian Institute for the Study of Continental Ecosystems IPEEC-CONICET-CENPAT Puerto Madryn Argentina Center for Demographic Urban and Environmental Studies El Colegio de México A.C. Mexico City Mexico Department of Agriculture Society and Environment El Colegio de la Frontera Sur San Cristóbal de Las Casas Mexico National Council of Science and Technology El Colegio de San Luis (CONACYT-COLSAN) San Luis Potosí Mexico Department of Life and Environmental Sciences Bournemouth University Dorset United Kingdom National Water Commission CONAGUA Mexico City Mexico Institute for Environmental Science and Technology Universitat Autonoma de Barcelona (ICTA-UAB) Barcelona Espa&ntilde a Institute for resources Environment and Sustainability (IRES) The University of British Columbia Vancouver Canada

The limited availability of high-quality spatial data often limits the development of hydrological modelling in developing countries. Hydrological models with data at different scales may generate large uncertainties in modelling outputs. This study analysed the accuracy of four SWAT built models that combine soil and land use/land cover (LULC) data at the scale of 1:250,000 and 1:100,000 in a basin of mexico. SWAT model allowed determining that large-scale maps produced better results than data from small-scale. Sensitivity analysis with different soil data was less than LULC data. However, the small-scale can be used for exploratory purposes when testing SWAT performance.

关键词： map Scale SWAT model Soil Survey Land Use/Land Cover mexico