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Phylogeography and morphometric variation in the Cinnamon Hummingbird complex:Amazilia rutila(Aves:Trochilidae)

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Avian Research 2021年第4期12卷 509-525页

作者： melisa Vázquez-López Nandadevi Córtes-Rodríguez sahid m.Robles-Bello Alfredo Bueno-hernández Luz e.Zamudio-Beltrán Kristen Ruegg Blanca e.hernández-Baños museo de Zoología Facultad de CienciasUniversidad Nacional Autónoma de MéxicoApartado Postal04510 Mexico CityMexico Department of Biology Ithaca CollegeIthacaNY 14850USA museo de Zoología Facultad de Estudios Superiores ZaragozaUniversidad Nacional Autónoma de MéxicoMexico CityMexico Department of Biology Colorado State UniversityFort CollinsCO 80523USA

Background:The mesoamerican dominion is a biogeographic area of great interest due to its complex topography and distinctive climatic *** area has a large diversity of habitats,including tropical deciduous forests,which house a large number of endemic ***,we assess phylogeographic pattern,genetic and morphometric variation in the Cinnamon Hummingbird complex Amazilia rutila,which prefers habitats in this *** resident species is distributed along the Pacific coast from sinaloa—including the Tres marías Islands in mexico to Costa Rica,and from the coastal plain of the Yucatán Peninsula of mexico south to ***:We obtained genetic data from 85 samples of ***,using 4 different molecular markers(mtDNA:ND2,COI;nDNA:ODC,mUsK)on which we performed analyses of population structure(median-joining network,sTRU CTU Re,FsT,AmOVA),Bayesian and maximum Likelihood phylogenetic analyses,and divergence time *** order to evaluate the historic suitability of environmental conditions,we constructed projection models using past scenarios(Pleistocene periods),and conducted Bayesian skyline Plots(BsP)to visualize changes in population sizes over *** analyze morphometric variation,we took measurements of 5 morphological traits from 210 study *** tested for differences between sexes,differences among geographic groups(defined based on genetic results),and used PCA to examine the variation in multivariate ***:Using mtDNA,we recovered four main geographic groups:the Pacific coast,the Tres marías Islands,the Chiapas region,and the Yucatán Peninsula together with Central *** same groups were recovered by the phylogenetic results based on the multilocus *** based on BsP results showed constant population size over time throughout the *** complex and within each geographic *** niche model projec-tions onto past scenarios revealed no drastic changes in suitable conditions,but revealed some

关键词： Amazilia rutila Genetic structure Genetic variation Phylogeography Tres marías Islands Trochilidae Tropical deciduous forest

3-Nitropropionic acid modifies neurotrophin mRNA expression in the mouse striatum: 18s-rRNA is a reliable control gene for studies of the striatum

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Neuroscience Bulletin 2012年第5期28卷 517-531页

作者： s.espíndola A Vilches-Flores e.hernández-echeagaray Unidad de Biomedicina FES-I Universidad Nacional Autónoma de México Los Reyes IztacalaC. P. 54090 TlalnepantlaMéxico

Objective The aim of the present study was to determine the changes in the mRNA levels of neurotrophins and their receptors in the striatal tissue of mice treated with 3-nitropropionic acid （3-NP）. methods At 1 and 48 h after the last drug administration, the mRNA expression of nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin-4/5 as well as their receptors p75, TrkA, TrkB and TrkC, was evaluated using semi-quantitative （semi- Q） and real-time RT-PCR. β-actin mRNA and ribosomal 18s （18s rRNA） were tested as internal controls. Results 3-NP treatment did not affect mRNA expression of all neurotrophins and their respective receptors equally. Also, differences in neurotrophin and receptor mRNA expression were observed between semi-Q and real-time RT-PCR. Real-time RT-PCR was more accurate in evaluating the mRNA expression of the neurotrophins than semi-Q, and 18s rRNA was more reliable than β-actin as an internal control. Conclusion Neurotrophins and their receptors expression is differentially affected by neuronal damage produced by inhibition of mitochondrial respiration with 3-NP treatment in low, sub-chronic doses in vivo.

关键词： neurotrophins striatum neurodegenerative disease PCR 18s 3-nitropropionic acid

Design of multilayer hybrid sol-gel coatings with bifunctional barrier-bioactive response on the elektron 21 magnesium alloy for biomedical applications

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Journal of magnesium and Alloys 2021年第6期9卷 2097-2112页

作者： K.s.Durán N.hernández L.m.Rueda C.A.hernández-Barrios A.e.Coy F.Viejo Grupo de Investigación en Desarrollo y Tecnología de Nuevos materiales(GImAT) Universidad Industrial de Santander9 Cra.27Colombia Grupo de Investigación de las Ciencias de las Ingenierías(GICI) Universidad de San BuenaventuraCartagenaCalle Real de TerneraDiagonal 32#30-966Colombia

The present study aims to develop multilayer barrier-bioactive hybrid sol-gel coatings from a mixture of the silane precursors tetraethylorthosilicate(TeOs)and glycidoxypropyltriethoxysilane(GPTms)deposited on the elektron 21 magnesium *** purpose of the inner layer(barrier coating)was to provide corrosion protection to the magnesium alloy,whereas the outer layer(bioactive coating)was doped with different Ca and mg contents to produce a bioactive *** coatings were characterised using scanning electron microscopy(sem)and their corrosion behaviour was evaluated by anodic polarisation and electrochemical impedance spectroscopy after immersion in simulated body fluid(sBF)at 37±0.5°*** experimental results showed that the multilayer coatings increased the corrosion resistance of the alloy up to three orders of magnitude during immersion in sBF *** the other hand,the presence of Ca and mg in the bioactive coating promoted the growth of apatite-like ***,an increment of salt content favoured the formation of porous coatings,which allowed the access of the electrolyte to the substrate leading to their rapid *** the latter,this research endorses the premise that the TeOs-GPTms hybrid system represents a promising alternative to produce bifunctional barrier-bioactive coatings.

关键词： magnesium bioactivity coating sol-gel eIs corrosion

Kinematic calibration of precise 6-DOF stewart platform-type positioning systems for radio telescope applications

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Frontiers of mechanical engineering 2013年第3期8卷 252-260页

作者： Juan Carlos JUReGUI eusebio e.hernndez marco CeCCAReLLI Carlos LOPeZ-CAJUN Alejandro GARCIA División de estudios de Posgrado Facultad de IngenieríaUniversidad Autónoma de Quéretaro QuéretaroQro.Mexico National Polytechnic Institute IPNSection of Graduate Studies and ResearchESIME-UPTMéxico D.F.Mexico Laboratory of Robotics and mechatronics University of Cassino Italy Universidad Autónoma de Quéretaro Querétaro Qro.México CIATeQ A.C.AguascalientesAgs.México

The pose accuracy of a parallel robot is a function of the mobile platform ***,there is no a single value of the robot’s *** this paper,two novel methods for estimating the accuracy of parallel robots are *** the frst method,the pose accuracy estimation is calculated by considering the propagation of each error,i.e.,error variations are considered as a function of the actuator’s *** the second method,it is considered that each actuator has a constant error at any *** methods can predict pose accuracy of precise robots at design stages,and/or can reduce calibration time of existing *** example of a six degree-of-freedom parallel manipulator is included to show the application of the proposed methods.

关键词： pose errors error estimation parallel robot radio telescopes

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 *** 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 *** 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 *** 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 *** 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

Pronuclear formation by ICsI using chemically activated ovine oocytes and zona pellucida bound sperm

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Journal of Animal science and Biotechnology 2017年第2期8卷 370-377页

作者： J.e.hernández-Pichardo Y.Ducolomb s.Romo m.e.Kjelland R.Fierro F.Casillas m.Betancourt División de Ciencias Biológicas y de la salud Departamento de Producción Agrícola y AnimalUniversidad Autónoma Metropolitana-XochimilcoCiudad de MexicoMexico Division de Ciencias Biologicas y de la salud Departamento de Ciencias de la SaludUniversidad Autónoma Metropolitana-IztapalapaSan Rafael Atlixco 186CP 09340 Ciudad de MexicoMexico Departamento de Ciencias Pecuarias Facultad de EstudiosSuperiores CuautitlanUNAMCiudad de MexicoEstado de MexicoMexico Conservation Genetics&BiotechLLCValley CityNDUSA Division de Ciencias Biologicas y de la salud Departamento de Biologia de la ReproduccionUniversidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico Doctorado en Biologia experimental Universidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico

Background： In order to improve ICsI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICsI with chemically activated ovine oocytes and sperm selected by swim up（sU） or swim up ＋ zona pellucida（sU ＋ ZP） ***： experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation（precense of one PN）. Treatments showed similar results（54, 47, 42 %, respectively） but statistically differents（P 0.05）.Conclusions： Chemical activation induces higher ovine oocyte activation than mechanical activation. ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. sperm selection with sU ＋ ZP increased AR/A and AR/D rates in comparison with sU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after ICsI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with sU and sU ＋ ZP were significantly different than frozen-thawed sperm,but between sperm treatments no significant differences were obtained.

关键词： ethanol ICsI Oocyte activation Ovine Pronucleus Zona pellucida

Using GeDI lidar data and airborne laser scanning to assess height growth dynamics in fast-growing species:a showcase in spain

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Forest ecosystems 2021年第1期8卷 182-198页

作者： Juan Guerra-hernández Adrián Pascual 3edata Centro de iniciativas empresariaisFundación CEL.O Palomar s/n27004 LugoSpain Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349-017 LisbonPortugal Center for Global Discovery and Conservation science Arizona State UniversityHiloHA 96720USA

Background:The NAsA’s Global ecosystem Dynamics Investigation(GeDI)satellite mission aims at scanning forest ecosystems on a multi-temporal short-rotation *** GeDI data can validate and update statistics from nationwide airborne laser scanning(ALs).We present a case in the Northwest of spain using GeDI statistics and nationwide ALs surveys to estimate forest dynamics in three fast-growing forest ecosystems comprising 211,346 *** objectives were:i)to analyze the potential of GeDI to detect disturbances,ii)to investigate uncertainty source regarding non-positive height increments from the 2015–2017 ALs data to the 2019 GeDI laser shots and iii)to estimate height growth using polygons from the Forest map of spain(Fms).A set of 258 National Forest Inventory plots were used to validate the observed height ***:The spatio-temporal assessment from ALs surveying to GeDI scanning allowed the large-scale detection of *** mean annual height growths were 0.79(sD=0.63),0.60(sD=0.42)and 0.94(sD=0.75)m for Pinus pinaster,Pinus radiata and eucalyptus spp.,*** median annual values from the ALs-GeDI positive increments were close to NFI-based growth values computed for Pinus pinaster and Pinus radiata,*** effect of edge border,spatial co-registration of GeDI shots and the influence of forest cover in the observed dynamics were important factors to considering when processing ALs data and GeDI ***:The use of GeDI laser data provides valuable insights for forest industry operations especially when accounting for fast ***,errors derived from positioning,ground finder and canopy structure can introduce uncertainty to understand the detected growth patterns as documented in this *** analysis of forest growth using ALs and GeDI would benefit from the generalization of common rules and data processing schemes as the GeDI mission is increasingly being utilized in the forest remote sensing community.

关键词： Forest inventory Productivity multi-temporal LiDAR Full-waveform(FW) satellite mapping

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

synthesis of activated carbons from black sapote seeds,characterization and application in the elimination of heavy metals and textile dyes

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Chinese Journal of Chemical engineering 2020年第2期28卷 613-623页

作者： Alejandra Alicia Peláez-Cid Vincent Romero-hernández Ana maría Herrera-González Alejandro Bautista-hernández Oscar Coreno-Alonso Facultad de Ingeniería Benemérita Universidad Autónoma de PueblaMexico Instituto de Ciencias Básicas e Ingeniería Universidad Autónoma del Estado de HidalgoMexico División de Ingenierías Universidad de GuanajuatoMexico

many different techniques may be used to remove industrial pollutants from wastewater. Adsorption using activated carbon has been reported to be an effective method. This work proposes the use of a vegetable residue(black sapote seeds) as a raw material for its synthesis. These carbons were chemically activated using phosphoric acid and carbonized at 673 and 873 K. Adsorption isotherms were constructed for the textile dyes on the carbons, and this data was treated using Langmuir’s equation to quantitatively describe the adsorption process. The synthesized carbons were characterized using FTIR, eA, sem, Nitrogen adsorption(specific surface areas of 879 and 652 m2·g-1), and their points of zero charge(2.1 and 2.3). It was possible to adsorb both heavy metals and textile dyes present in aqueous solutions and wastewaters using these activated carbons. Heavy metals were adsorbed almost completely by both carbons. Cationic dyes where adsorbed(58–59.8 mg·g-1) in greater amounts compared to anionic dyes(10–58.8 mg·g-1). The amount of anionic dyes adsorbed increased almost 30% by changing the pH of the solutions. One of the carbons was thermally regenerated on three occasions without losing its adsorption capacity and it was proved in a flow system.

关键词： Activated carbons Black sapote seeds Heavy metal adsorption Textile dye adsorption Wastewater treatment