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Host-parasite interactions in perpetual darkness:Macroparasite diversity in the cavefish Astyanax mexicanus

Zoological Research 2023年第4期44卷 782-792页

作者： Ana Santacruz David Hernández-Mena Ramses Miranda-Gamboa Gerardo Pérez-Ponce de León Claudia Patricia Ornelas-García departamento de Zoología Instituto de BiologíaUniversidad Nacional Autónoma de MéxicoMéxico City CP 04510México departamento de Sistemas y Procesos Naturales Escuela Nacional de Estudios Superiores Unidad MéridaUcúYucatán CP 97357México Instituto de Energías Renovables Universidad Nacional Autónoma de MéxicoTemixcoMorelos CP 62580México Colección Nacional de Peces Departamento de ZoologíaInstituto de BiologíaUniversidad Nacional Autónoma de MéxicoMéxico City CP 04510México Stowers Institute for Medical Research Kansas CityMO 64110USA

Astyanax mexicanus has repeatedly colonized cave environments,displaying evolutionary parallelisms in many troglobitic traits.despite being a model system for the study of adaptation to life in perpetual darkness,the parasites that infect cavefish are practically unknown.In this study,we investigated the macroparasite communities in 18 cavefish populations from independent lineages and compared them with the parasite diversity found in their sister surface fish populations,with the aim of better understanding the role that parasites play in the colonization of new environments.Within the cavefish populations,we identified 13 parasite taxa,including a subset of 10 of the 27 parasite taxa known for the surface populations.Parasites infecting the cavefish belong to five taxonomic groups,including trematodes,monogeneans,nematodes,copepods,and acari.Monogeneans are the most dominant group,found in 14 caves.The macroparasites include species with direct life cycles and trophic transmission,including invasive species.Surprisingly,paired comparisons indicate higher parasite richness in the cavefish than in the surface fish.Spatial variation in parasite composition across the caves suggests historical and geographical contingencies in the host-parasite colonization process and potential evolution of local adaptations.This base-line data on parasite diversity in cavefish populations of A.mexicanus provides a foundation to explore the role of divergent parasite infections under contrasting ecological pressures(cave vs.surface environments)in the evolution of cave adaptive traits.

关键词： Adaptation Metazoan parasites Niche change Parasite assemblage Prevalence

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The impact of crustal rheology on natural seismicity: Campi Flegrei caldera case study

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Geoscience Frontiers 2019年第2期10卷 453-466页

作者： R.Castaldo L.D'Auria S.Pepe G.Solaro V.de Novellis P.Tizzani Istituto per il Rilevamento Elettromagnetico dell'Ambiente (IREA)-Consiglio Nazionale delle Ricerche (CNR) instituto Volcanológico de Canarias (INVOLCAN) instituto Tecnológico y de energías renovables (ITER)

We analyze the crustal rheology beneath the active resurgent Campi Flegrei caldera(CFc) in Southern Italy by modelling the 3 D brittle-ductile(B/D) transition, based on available thermal, geological and geophysical data. Firstly, the thermal field in the conductive physical regime is modeled using a finite element method; based on an optimization tool, this method is applied to evaluate the location and dimensions of the deep thermal source beneath the caldera. A horizontally-extended thermal anomaly located at about 5000 m depth below sea level is identified beneath Pozzuoli Bay, a part of the CFc. The same isotherm is located at a depth of 20,000 m beyond the caldera. This indicates a higher horizontal temperature gradient in the caldera with respect to the surrounding area. Next, we utilize this thermal model to image the 3D rheological stratification of the shallow crust below the caldera with two different values of strain rates. Within the caldera, the B/D transitions with ε equal to 10^(-12) s^(-1) and 10^(-8) s^(-1) are located at 3000 m and 5000 m depths, respectively. Outside the caldera, the transition is very deep(15,000-20,000 m), seemingly uninfluenced by the thermal state of the CFc volcanism. Finally, we compare these results with the spatial distribution of earthquake hypocenters, Benioff strain release and b-value distribution to investigate the relationship between crustal rheology and seismicity characteristics. Our analysis reveals that the image of the B/D transition is in agreement with the distribution of earthquake hypocenters, constraining the potential seismogenic volume of the region. Our study demonstrates that knowledge of the rheological state of a volcanic system is an important element to interpret its dynamic, forecast future activity and improve evaluation of the associated seismic hazard.

关键词： Brittle-ductile transition Seismicity cut-off Geothermal measurements FE conductive thermal modelling Campi Flegrei caldera

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The anthocyanin's role on the food metabolic pathways,color and drying processes:An experimental and theoretical approach

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Food Bioscience 2022年第3期47卷 91-110页

作者： Sandra Peñaloza Cornelio delesma Jesús Muñiz López-Ortiz A. Instituto de Energías Renovables Universidad Nacional Autónoma de MéxicoPriv.Xochicalco s/nCol.CentroTemixco62580MorelosMexico

This review is intended to cover the works related to the anthocyanin behavior in food that is subjected to drying.Both experimental and theoretical results available in scientific literature are discussed.An increase in anthocyanin concentration has been observed upon thermal processing.Nevertheless,a conclusive explanation is still unavailable.The accessible studies suggest an increase in concentration during maturations,which could be related to the enzymatic activity.The possible enzymes involved in such a procedure have also been covered,including their role played in the process.The possible activation mechanisms and the related factors such as temperature,pH,oxygen contents and the presence of UV-light irradiation were also considered.Moreover,the metabolic pathways were also explored including experimental evaluation and theoretical models based on atomistic methodologies such as density functional theory(DFT).This review is aimed to provide a comprehensive overview of the probable mechanisms behind the increase of anthocyanin concentration during drying.

关键词： Anthocyanin Metabolic pathway PAL CHS UFGT HPLC Theoretical model

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Mitochondrial phylogeography and molecular evolution of the rhodopsin visual pigment in troglobitic populations of Astyanax mexicanus(de Filippi,1853)

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Zoological Research 2023年第4期44卷 761-775页

作者： Marco A.A.Garduño-Sánchez Vladimir de Jesus-Bonilla Silvia Perea Ramses Miranda-Gamboa Andrea Herrera-García Mauricio de la Maza Benignos Claudia Patricia Ornelas-García Colección Nacional de Peces Departamento de ZoologíaInstituto de BiologíaUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoC.P.04510México Posgrado en Ciencias Biológicas Colección Nacional de PecesDepartamento de ZoologíaInstituto de BiologíaUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoC.P.04510México Licenciatura en Ciencias Forenses Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoCiudad UniversitariaCoyoacánMéxico CityC.P.04510México Instituto de Energías Renovables Universidad Nacional Autónoma de MéxicoTemixcoMorelos C.P.62580Mexico Facultad de Ciencias Biológicas Universidad Autónoma de Nuevo LeónCiudad UniversitariaSan Nicolás de los GarzaNuevo LeónC.P.66450México

Cave-adapted animals provide a unique opportunity to study the evolutionary mechanisms underlying phenotypic,metabolic,behavioral,and genetic evolution in response to cave environments.The Mexican tetra(Astyanax mexicanus)is considered a unique model system as it shows both surface and cave-dwelling morphs.To date,at least 33 different cave populations have been identified,with phylogenetic studies suggesting an origin from at least two independent surface lineages,thereby providing a unique opportunity to study parallel evolution.In the present study,we carried out the most exhaustive phylogeographic study of A.mexicanus to date,including cave and surface localities,using two mitochondrial markers(cytochrome b(cyt b)and cytochrome c oxidase subunit I(COI))and nuclear rhodopsin visual pigment(rho).Additionally,we inferred the molecular evolution of rho within the two contrasting environments(cave and surface)and across three geographic regions(Sierra de El Abra,Sierra de Guatemala,and Micos).In total,267 individuals were sequenced for the two mitochondrial fragments and 268 individuals were sequenced for the rho visual pigment from 22 cave and 46 surface populations.Phylogeographic results based on the mitochondrial data supported the two-lineage hypothesis,except for the Pachón and Chica caves,whose introgression has been largely documented.The Sierra de El Abra region depicted the largest genetic diversity,followed by the Sierra de Guatemala region.Regarding the phylogeographic patterns of rho,we recovered exclusive haplogroups for the Sierra de El Abra(Haplogroup I)and Sierra de Guatemala regions(Haplogroup IV).Moreover,a 544 bp deletion in the rho gene was observed in the Escondido cave population from Sierra de Guatemala,reducing the protein from seven to three intramembrane domains.This change may produce a loss-of-function(LOF)but requires further investigation.Regarding nonsynonymous(dN)and synonymous(dS)substitution rates(omega valuesω),our results revealed the prevailing influence of purifying selection

关键词： Visual pigments Selection Cavefish Vision loss Loss of function

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Highly graphitized carbon nanosheets with embedded Ni nanocrystals as anode for Li-ion batteries

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Nano Research 2020年第1期13卷 86-94页

作者： Francisco Javier Soler-Piña Celia Hernández-Rentero Alvaro Caballero Julián Morales Enrique Rodríguez-Castellón Jesús Canales-Vázquez Dpto.Química Inorgánica e Ingeniería Química Instituto de Química Fina y NanoquímicaUniversidad de Córdoba14071CórdobaSpain Dpto.Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071MálagaSpain Instituto de Energías Renovables Universidad de Castilla-La ManchaPaseo de La Investigación 102071AlbaceteSpain

A C/Ni composite was prepared via thermal decomposition of a nickel oleate complex at 700℃,yielding disperse Ni nanocrystals with an average size of 20 nm,encapsulated by carbon nanosheets as deduced from transmission electron microscopy(TEM)images and confirmed from X-ray photoelectron spectroscopy(XPS).Furthermore,the X-ray diffraction pattern revealed a good ordering of the carbon layers,forced by the Ni encapsulation to adopt a bending structure.Considering the close interaction between the graphitized framework and the metallic nanoparticles we have studied the properties of the composite as an anode for Li-ion batteries.Compared with other nanostructured synthetic carbons,this carbon composite has a low voltage hysteresis and a modest irreversible capacity value,properties that play a significant role in its behaviour as electrodes in full cell configuration.At moderate rate values,0.25 C,the electrode delivers an average capacity value around 723 mAh·g^−1 on cycling,among the highest values so far reported for this carbon type.At higher rate values,1 C,the average capacity values delivered by the cell on cycling decrease,around 205 mAh·g^−1,but it maintains good capacity retention,a coulombic efficiency close to 100%after the first cycles and recovery of the capacity values when the rate is restored from 3 to 0.1 C.

关键词： carbon nanosheets nickel nanoparticles anode lithium batteries

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Influence of acid and alkaline sources on optical, structural and photovoltaic properties of CdSe nanoparticles precipitated from aqueous solution

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Frontiers of Materials Science 2016年第2期10卷 168-177页

作者： C. Selene CORIA-MONROY Merida SOTELO-LERMA Hailin HU instituto de energias renovables Universidad Nacional Autonoma de Mexico (UNAM) Priv. Xochicalco S/N 62580 Temixco Morelos Mexico Universidad de Sonora Blvd. Luis Encinas y Rosales S/N Col. Centro Hermosillo Sonora Mexico

CdSe is a widely researched material for photovoltaic applications. One of the most important parameters of the synthesis is the pH value, since it determines the kinetics and the mechanism of the reaction and in consequence, the optical and morphological properties of the products. We present the synthesis of CdSe in solution with strict control of pH and the comparison of ammonia and KOH as alkaline sources and diluted HCI as acid medium. CdSe formation was monitored with photoluminescence emission spectra （main peak in 490 nm, bandgap of CdSe nanoparticles）. XRD patterns indicated that CdSe nanoparticles are mainly of cubic structure for ammonia and HCI, but the hexagonal planes appear with KOH. Product yield decreases with pH and also decreases with KOH at constant pH value since ammonia has a double function, as complexing agent and alkaline source. Changes in morphology were observed in SEM images as well with the different alkaline source. The effect of alkaline sources on photovoltaic performance of hybrid organic solar cells with CdSe and poly（3-hexylthio- phene） as active layers was clearly observed, indicating the importance of synthesis conditions on optoelectronic properties of promising semiconductor nanomaterials for solar cell applications.

关键词： CdSe optical properties morphological properties hybrid solar cells

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New discriminant-function-based multidimensional discrimination of mid-ocean ridge and oceanic plateau

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Geoscience Frontiers 2020年第5期11卷 1681-1693页

作者： Surendra P.Verma Lorena Diaz-Gonzalez instituto de energias renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco S/no.Col.CentroApartado Postal 34TemixcoMor62580Mexico Centro de Investigacion en Ciencias Universidad Autonoma de Estado de MorelosCuernavacaMorelos62209Mexico

From a compilation of geochemical data for the discrimination of the tectonic settings of mid-ocean ridge(MOR;3730 samples)and oceanic plateau(OP;3656 samples),we present two new discriminant functions and diagrams obtained from censored multivariate discordant outlier-free datasets.Ten different sets of data(original concentrations as well as isometric log-ratio transformed(ilr)variables;all 10 major(M)elements as well as all 10 major and 6 trace elements MT)were used to evaluate the quality of discrimination from linear discriminant analysis(LDA)and canonical analysis.Two selected multidimensional models ilrM(9 ilr transformed variables of multi-normally distributed 10 major elements)and ilrMT(15 ilr transformed variables of multi-normally distributed combined 10 major and 6 trace elements),considered as the best or most representative(total of5650 samples for ilrM and 2858 for ilrMT),provided percent success values,respectively,of 80.9%for the MOR and 81.1%for the OP(ilrM)and 88.5%for the MOR and 90.1%for the OP(ilrMT).Both processes(log-ratio transformation and multi-normality)rendered the percent success values similar for both groups(MOR and OP).The respective discriminant functions were successfully used for four tests from known tectonic settings and four application cases(two for ophiolites and two for Precambrian rocks),documenting thus the utility of the new discrimination procedure for the MOR and OP tectonic settings.Furthermore,we showed that our multidimensional procedure is robust against analytical errors or uncertainties,as well as post-emplacement compositional changes caused by element mobility from both low or high temperature alteration.The robustness against the gain or loss of a single element at a time was also documented,from which the ilrMT model was evaluated as more robust than the ilrM model.A new online computer program MOROPdisc was written in Java Framework ZK,which is freely available for use at our web portal http://tlaloc.***.unam.mx.

关键词： MORB Multivariate discordant outliers Log-ratio transformation Multidimensional discrimination Analytical uncertainties Post-emplacement changes

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Physical activation of graphene: An effective, simple and clean procedure for obtaining microporous graphene for high-performance Li/S batteries

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Nano Research 2019年第4期12卷 759-766页

作者： Almudena Benitez Alvaro Caballero Julian Morales Jusef Hassoun Enrique Rodriguez-Castellon Jesus Canales-Vazquez Dpto. Quimica Inorganica e Ingenieria Qutmica Instituto de Quimica Fina y Nanoquimica Universidad de Cordoba 14071 Cordoba Spain departm ent of Chemical and Pharmaceutical Sciences University of Ferrara Via Fossato di Mortara 17 44121 Ferrara Italy Dpto. de Quimica Inorganica Cristalografia y Mineralogia Facultad de Ciencias Universidad de Malaga 29071 Malaga Spain instituto de energias renovables Universidad de Castilla-La Mancha Paseo de La Investigacion 1 Albacete 02071 Spain

Graphe ne nano sheets are a promising scaffold to accommodate S for achievi ng high performa nee Li/S battery. Nano sheet activation is used as a viable strategy to induce a micropore system and further improve the battery performance. Accordingly, chemical activation methods dominate despite the need of multiple stages, which slow down the process in addition to making them tiresome. Here, a three-dimensional (3D) N-doped graphene specimen was physically activated with CO2, a clean and single step process, and used for the preparation of a sulfur composite (A-3DNG/S). The A-3DNG/S composite exhibited outstanding electrochemical properties such as an excellent rate capability (1,000 mAh·g^-1 at 2C), high reversible capacity and cycling stability (average capacity ~ 800 mAh·g^-1 at 1C after 200 cycles), values which exceed those measured in chemically activated graphene. Therefore, these results support the use of physical activation as a simple and efficient alternative to improve the performance of carbons as an S host for high-performance Li-S batteries.

关键词： physical activation 3D-graphene solvothermal microwave synthesis Li-S battery

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Small-signal Model for Dual-active-bridge Converter Considering Total Elimination of Reactive Current

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Journal of Modern Power Systems and Clean energy 2021年第2期9卷 450-458页

作者： Juan Ramon Rodriguez-Rodriguez Nadia Maria Salgado-Herrera Jacinto Torres-Jimenez Nestor Gonzalez-Cabrera David Granados-Lieberman Martin Valtierra-Rodriguez the Universidad Nacional Autonoma de Mexico Facultad de IngenieriaDepto.Energia Electri-ca.Av.Universidad 3000Col.UNAM CUCoyoacanCDMXMexico the instituto de energias renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco s/nCol.Centro.TemixcoMorelosMexico the instituto Tec-nologico Superior de Irapuato Carretera Irapuato-Silao km 12.5.IrapuatoGuanajuatoMexico the Universidad Autonoma de Queretaro Campus San Juan del RioRio Moctezuma 249San Juan del RioQueretaroMexico

Emerging technologies such as electric vehicles,solid-state transformers,and DC transformers are implemented using the closed-loop bi-directional dual-active-bridge(DAB)converter.In this context,it is necessary to have average models that provide an efficient way of tuning the proportional integral(PI)compensator parameters for large-and small-signal applications.We present a novel small-signal model(SSM)for DAB converter with a single closed-loop PI controller and the total elimination of reactive current(IQ=0).The method applies a modulation technique for IQ=0 and introduces a composite function in the controller while reducing the original nonlinear switching model,which allows to decrease the order of the transfer function and analyze the closed-loop operation.The proposed SSM is analyzed using different response time,load,and DC voltage changes.The simulation and experimental results demonstrate the ease of implementation and effectiveness of the proposed model with respect to other SSM techniques.

关键词： Small-signal model(SSM) dual-active-bridge(DAB)converter reactive current elimination proportional integral(PI)control

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Using detection dogs and genetic analyses of scat to expand knowledge and assist felid conservation in Misiones, Argentina

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Integrative Zoology 2014年第5期9卷 623-639页

作者： Karen E.deMATTEO Miguel A.RINAS Carina F.ARGÜELLES Bernardo E.HOLMAN Mario S.DI BITETTI Barbara DAVENPORT Patricia G.PARKER Lori S.EGGERT department of Biology University of MissouriSt.LouisUSA WildCare Institute at the Saint Louis Zoo St.LouisUSA Ministerio de Ecología y Recursos Naturales renovables Argentina instituto de Biología Subtropical(IBS)-nodo Posadas Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)-Universidad Nacional de Misiones(UNaM)Argentina Facultad de Ciencias Exactas Químicas y NaturalesUNaMArgentina IBS-nodo Puerto Iguazú CONICET-UNaMArgentina Asociación Civil Centro de Investigaciones del Bosque Atlántico Argentina PackLeader Dog Training LLC Division of Biological Sciences University of MissouriColumbiaUSA

Many carnivores require large ranges to meet their ecological and energetic needs;however,anthropogenic changes threaten species and their habitats.Camera traps have been used to effectively collect data on carnivores in a variety of habitat types;however,a single survey effort is typically limited to species that have similar body size,habitat use and movement patterns,and individual identification of animals is not always possible.We evaluated whether scat detection dogs could effectively survey for 4 wide-ranging felids that vary in these characteristics:jaguars(Panthera onca),pumas(Puma concolor),ocelots(Leopardus pardalis)and oncillas(Leopardus tigrinus).From June to October 2009 and May to August 2011,a detection dog-handler team detected 588 scats,from which 176 unique genotypes were detected.We assigned sex to 84.7%of the genotyped scats and identified 55 individuals multiple times.The effectiveness of these noninvasive techniques(detection dogs and genetic analyses of scat)not only opens the door for additional studies in areas that were previously difficult or impossible with standard survey techniques,but also provides conservationists with a set of tools that overcome some of the limitations associated with the use of camera traps alone.

关键词： conservation detection dogs felids genetics noninvasive techniques

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