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Open Journal of Marine Science 2016年第3期6卷 386-394页

作者： Ruth A. Pérez-Campos Oswaldo huchim-Lara Silvia Salas María Liceaga-Correa héctor hernández-nuñez Cristina Pascual-Jiménez Pascual-Jiménez Rossanna Rodríguez-Canul Laboratorio de Inmunología y Biología Molecular Mérida Yucatán México Laboratorio de Pesquerías Mérida Yucatán México Laboratorio de Percepción Remota y Sistemas de Información Geográfica Centro de Investigación y de Estudios Avanzados del IPN-Mérida (CINVESTAV-IPN) Merida Mexico Universidad Nacional Autónoma de México Facultad de Ciencias Unidad Académica Sisal Sisal Mexico

Panulirus argus virus 1 (PaV1) is considered a major threat to spiny lobsters Panulirus argus. In this study Geospatial analysis was used to analyze PaV1 distribution in an artisanal fishery of spiny lobster Panulirus argus population from the north coast of the Yucatan Peninsula. Adult and sub-adult P. argus and seabed coverage data were collected from thirty artisanal fishing sites. Five seabed coverage types were identified: seagrass;sand/seagrass mixture;sand only;coral/sand mixture;and seaweed. No juveniles were examined. Of the 358 collected lobsters, PaV1 was identified in four organisms (three sub-adults and one adult) from two fishing sites (termed A & B), both found in a seagrass coverage area. Overall prevalence was of 1.12%. Prevalence was of 20% (2/10) at one site and of 12.6% (2/16) at the other.

关键词： Panulirus argus PaV1 Geospatial Analysis Artisanal Fishery Seagrass

The ecological scale mediates whether trees experience drought legacies in radial growth

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Forest Ecosystems 2023年第3期10卷 298-306页

作者： héctor hernández-Alonso Jaime Madrigal-González Fernando Silla Area of Ecology Faculty of BiologyUniversidad de SalamancaE-37007SalamancaSpain iuFOR-EiFAB Campus de SoriaUniversidad de ValladolidE-42004SoriaSpain

The impact of lag effects produced by disturbances on primary production has been a major concern among ecologists during the last *** and extreme climatic events are imposing drastic reductions in radial growth of trees as evidenced in tree-rings series Dendrochronological samples are obtained at tree level but analyzed at an aggregated scale(i.e.,mean chronologies),although aggregating tree-ring chronology on a regional scale may reduce the possibility of studying the variability of individual tree response to drought,by amplifying the average population ***,we conducted experimental research in which 370 trees of 5 species were analyzed to assess the potential statistical and scaling issues that may occur when using regressionbased methods to analyze ecosystem responses to *** legacy effects were quantified using individual and aggregated ***,lag effects were validated using confidence and prediction intervals to identify values falling outside the certainty of the climate-growth model Individual scale legacy effects contrasted with confidence intervals were commonly distributed across species but were scarce when compared with prediction *** analysis of aggregated scale legacies detected significant growth reductions when validated using prediction intervals;however,individual scale legacy lag effects were not *** finding directly contrasts the results obtained when using an aggregated *** results provide empirical evidence on how aggregating ecological data to infer processes that emerge from an individual scale can lead to distorted *** therefore encourage the use of individual based statistical and ecological procedures to analyze tree rings as a means of further understanding the ecosystem responses to disturbances.

关键词： Legacy effects Drought disturbances Tree growth Tree-ring width Dendrochronology Individual scale Mountainous forests

Kinetic study of austenite formation during continuous heating of unalloyed ductile iron

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 27-31页

作者： Octvio Vazquez-Gómez Jos Antonio Barrera-Godínez hctor Javier Vergara-hernndez Faculty of Chemistry Metallurgical Engineering DepartmentAutonomous National University of Mexico Metallurgy Science Postgraduate Programme Morelia Institute of Technology

The austenite formation kinetics in unalloyed cast ductile iron was studied on the basis of dilatometry measurements, and Avrami＇s equation was used to estimate the material＇s kinetic parameters. A continuous heating transformation diagram was constructed us-ing heating rates in the range of 0.06 to 0.83℃·s^-1. As the heating rate was augmented, the critical temperatures, c1A and Aα, as well as the intercritical range, which was evaluated as the difference between the critical temperatures, α c1Δ T =A_a- A_c1 , increased. At a low heating rate, the kinetics of austenite formation was slow as a consequence of the iron＇s silicon content. The effect of heating rate on k and n, the kinetic parameters of Avrami＇s equation, was also determined. Parameter n, which is associated with nucleation sites and growth geometry, de-creased with an increase in heating rate. In addition, parameter k increased with the increase of heating rate, suggesting that the nucleation and growth rates are carbon-and silicon-diffusion controlled during austenite formation under continuous heating.

关键词： ductile iron austenite continuous heating heating rate kinetics dilatometry

Effect of initial microstructure on austenite formation kinetics in high-strength experimental microalloyed steels

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1304-1312页

作者： Edgar López-Martínez Octavio Vázquez-Gómez héctor Javier Vergara-hernández Bernardo Campillo Faculty of Chemistry Metallurgical Engineering Department Autonomous National University of Mexico National Council for Science and Technology Metallurgy Science Postgraduate Programme Morelia Institute of Technology Institute of Physical Sciences Autonomous National University of Mexico

Austenite formation kinetics in two high-strength experimental microalloyed steels with different initial microstructures comprising bainite-martensite and ferrite-martensite/austenite microconstituents was studied during continuous heating by dilatometric analysis. Austenite formation occurred in two steps：（1） carbide dissolution and precipitation and （2） transformation of residual ferrite to austenite. Dilatometric analysis was used to determine the critical temperatures of austenite formation and continuous heating transformation diagrams for heating rates ranging from 0.03°C.s^-1 to 0.67°C.s^-1. The austenite volume fraction was fitted using the Johnson-Mehl-Avrami-Kolmogorov equation to determine the kinetic parameters k and n as functions of the heating rate. Both n and k parameters increased with increasing heat- ing rate, which suggests an increase in the nucleation and growth rates of austenite. The activation energy of austenite formation was determined by the Kissinger method. Two activation energies were associated with each of the two austenite formation steps. In the first step, the austenite growth rate was controlled by carbon diffusion from carbide dissolution and precipitation; in the second step, it was controlled by the dissolution of residual ferrite to austenite.

关键词： non-isothermal kinetics microalloyed steel austenite heating dilatometry

EXTRACTING BEhAVIOURAL MODELS FROM 2010FIFA WORLD CUP

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Journal of Systems Science & Complexity 2013年第1期26卷 43-61页

作者： MENndez héctor BELLO-ORGAZ Gema CAMAChO David Department of Computer Science Universidad Autnoma de Madrid

The FIFA World Cup^(TM) is the most profitable worldwide *** FIFA publishes global statistics of this competition which provide global data about the players and teams during the *** work is focused on the extraction of behavioural patterns for both,players and teams strategies,through the automated analysis of this *** knowledge and models extracted in this work could be applied to soccer leagues or even it could be oriented to sport ***,the main contribution is related to the study on several automatic knowledge extraction techniques,such as clustering methods,and how these techniques can be used to obtain useful behavioural models from a global statistics *** information provided by the clustering algorithms shows similar properties which have been combined to define the models,making the human interpretation of these statistics ***,the most successful teams strategies have been analysed and compared.

关键词： Behavioural patterns clustering FIFA World Cup football soccer web mining.

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

Getting started in mapping-by-sequencing

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Journal of Integrative Plant Biology 2015年第7期57卷 606-612页

作者： héctor Candela Rubén Casanova-Sáez José Luis Micol Instituto de Bioingeniería Universidad Miguel Hernández Department of Forest Genetics and Plant Physiology Umea Plant Science CenterSwedish University of Agricultural Sciences

Next-generation sequencing （NGS） technologies allow the cost-effective sequencing of whole genomes and have expanded the scope of genomics to novel applications, such as the genome-wide characterization of intraspecific polymorphisms and the rapid mapping and identification of point mutations. Next-generation sequencing platforms, such as the Illumina hiSeq2ooo platform, are now commercially available at affordable prices and routinely produce an enormous amount of sequence data, but their wide use is often hindered by a lack of knowledge on how to manipulateand process the information produced. In this review, we focus on the strategies that are available to geneticists who wish to incorporate these novel approaches into their research but who are not familiar with the necessary bioinformatic concepts and computational tools. In particular, we comprehensively summarize case studies where the use of NGS technologies has led to the identification of point mutations, a strategy that has been dubbed ＂mapping-by-sequencing＇, and review examples from plants and other model species such as Caenorhabditis elegans, Saccharomyces cerevisiae, and Drosophila mela- nogaster. As these technologies are becoming cheaper and more powerful, their use is also expanding to allow mutation identification in species with larger genomes, such as many crop plants.

关键词： Mapping-by-sequencing massively parallel sequencing mutation identification ShOREmapping whole-genome re-sequencing

Arrhythmogenic mechanisms in ryanodine receptor channelopathies

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Science China(Life Sciences) 2015年第1期58卷 54-58页

作者： ZhAO Yan-Ting VALDIVIA Carmen R. GURROLA Georgina B. hernndez Jonathan J. VALDIVIA héctor h. Center for Arrhythmia Research Department of Internal MedicineCardiovascular DivisionUniversity of Michigan

Ryanodine receptors(Ry Rs) are the calcium release channels of sarcoplasmic reticulum(SR) that provide the majority of calcium ions(Ca2+) necessary to induce contraction of cardiac and skeletal muscle *** their intracellular environment,Ry R channels are regulated by a variety of cytosolic and luminal factors so that their output signal(Ca2+) induces finely-graded cell contraction without igniting cellular processes that may lead to aberrant electrical activity(ventricular arrhythmias) or cellular *** importance of Ry R dysfunction has been recently highlighted with the demonstration that point mutations in RYR2,the gene encoding for the cardiac isoform of the Ry R(Ry R2),are associated with catecholaminergic polymorphic ventricular tachycardia(CPVT),an arrhythmogenic syndrome characterized by the development of adrenergically-mediated ventricular tachycardia in individuals with an apparently normal *** we summarize the state of the field in regards to the main arrhythmogenic mechanisms triggered by Ry R2 channels harboring mutations linked to *** CPVT mutations characterized to date endow Ry R2 channels with a gain of function,resulting in hyperactive channels that release Ca2+ spontaneously,especially during *** spontaneous Ca2+ release is extruded by the electrogenic Na+/Ca2+ exchanger,which depolarizes the external membrane(delayed afterdepolarization or DAD) and may trigger untimely action ***,a rare set of CPVT mutations yield Ry R2 channels that are intrinsically hypo-active and hypo-responsive to stimuli,and it is unclear whether these channels release Ca2+ spontaneously during *** discuss novel cellular mechanisms that appear more suitable to explain ventricular arrhythmias due to Ry R2 loss-of-function mutations.

关键词： ryanodine receptors CPVT sarcoplasmic reticulum cardiac arrhythmias

Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico,Tamaulipas state,Mexico:implication for provenance

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Journal of Palaeogeography 2024年第3期13卷 375-400页

作者： Mayank Shukla Sanjeet K.Verma Mayla A.Ramos-Vázquez John S.Armstrong-Altrin Karla R.hernández-Martínez Sumit Mishra Vivek P.Malviya héctor hernández-Mendoza Posgrado de la Division de Geociencias Aplicadas Instituto Potosino de Investigacion Científica y Tecnologica(IPICYT)Camino a la Presa San José2055San Luis Potosí78216Mexico Division de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnologica(IPICYT)Camino a la Presa San Jose 2055San Luis Potosí78216Mexico Universidad Nacional Autonoma de México Instituto de Ciencias del Mar y LimnologíaUnidad de ProcesosOceanicos y CosterosCiudad UniversitariaCiudad de México 04510Mexico Department of Marine Sciences Bharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Instituto de Geociencias Universidad Nacional Autonoma de MéxicoBoulevard Juriquilla 300176230JuriquillaQueretaroMexico Department of Applied Geology Dr.Harisingh Gour Central UniversitySagar470002Madhya PradeshIndia Instituto de Investigacion de Zonas Desérticas Universidad Autònoma de San Luis PotosíAltair 200CP 78377San LuisS.L.P.Mexico Universidad del Centro de Mexico Capitán Caldera 75CP 78250San LuisS.L.P.Mexico

Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of *** main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach *** sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and *** beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic *** chemical index of weathering(CIW’)indicates intense weathering in the source *** quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical *** features such as fractures,pits,percussion marks,abrasion fatigue,and V-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian *** chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine *** mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine *** and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),Sierra Madre Oriental(SMOr)and Oaxaquia *** major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.

关键词： Beach sediments Geochemistry Mineralogy Provenance Tamaulipas Tectonic setting

Effects of hedera helix *** on the understory early regeneration in an oak temperate forest in Mexico City

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Ecological Processes 2023年第1期12卷 438-449页

作者： héctor Adrián Jiménez-hernández Leticia Bonilla-Valencia Yuriana Martínez-Orea Mara Jessica Zamora-Almazan Francisco Javier Espinosa-García Silvia Castillo-Argüero Facultad de Ciencias Universidad Nacional Autónoma de MéxicoMexico CityMexico Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de MéxicoMichoacánMexico

Background hedera helix *** an invasive weed species introduced in several regions of the world,so it is relevant to study its effects on the plant community and the changes occurring after its *** established invaded(with/without removal of ***)and non-invaded(with/without removal of the understory)plots to compare some community attributes in an oak forest in Mexico City and monitored them every 2 months for 1 year,taking soil samples to compare some edaphic variables between the *** invasive species negatively affect natural regenera-tion,seedlings of native species would be less abundant in plots invaded by *** than in the non-invaded *** invasive species modify the soil microbiota through exudates and often allelochemicals,soil chemical variables would differ between invaded and non-invaded *** The abundance of native species was lower in the invaded plots,but the richness and diversity of species were not statistically *** composition of the two invaded plots was similar to each other and more alike to that of the non-invaded *** species composition of the invaded plots was associated with soil potassium and phosphorus concentrations,whereas that of the non-invaded plots was more associated with soil nitrogen *** Following the removal of ***,several native species were registered,leading to a similar species composition as in the non-invaded plots,suggesting that some vegetation recovery can be expected following *** removal in 1 year.

关键词： Ivy Invasive plant Mechanical control Diversity Species composition

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