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Cytogenetical Changes among Polyembryonic(PEm)and Non-PEm Maize Plants

Phyton-International journal of Experimental Botany 2021年第1期90卷 87-97页

作者： A.A.Román-Calzoncit F.Ramírez-Godina j.sánchez-laureano A.C.Flores-Gallegos j.Espinoza-Velázquez R.Rodríguez-Herrera school of Chemistry Universidad Autónoma de Coahuila.Blvd.V.Carranza e Ing.JoséCárdenas V.s/n.Col.República Ote.C.P.25280.SaltilloCoahuilaMéxico Plant Breeding Department Universidad Autónoma Agraria Antonio NarroBlvd.Antonio Narro 1923BuenavistaSaltilloMéxico

Polyembryony in maize(PEm)contributes to improving the nutritional properties of the grain,as well as an increase in yield,since it generates multiple plants per seed,opening the possibility of developing new varieties.However,it is unknown whether polyembryony in maize is the product of chromosomal abnormalities.Based on the above,in this research a cytogenetic study was proposed to verify if chromosomal abnormalities are related to the maize polyembryony.For a meiotic study,maize genotypes with variable proportions of polyembryony(PEm),from the UA-IMM-BAP population and non-PEm(monoembryonic)maize were used,while for a mitosis analysis,30 families of maternal half-siblings(MHs)from two different populations with high polyembryony,denominated as BHP(brachytic,high polyembryony)and NHP(normal height,high polyembryony)were used.All these genotypes were planted in the Buenavista Agricultural Experimental station-UAAAN at saltillo,Coahuila,Mexico.The frequency of PEm was estimated in all genotypes.It was found that the polyembryony occurs at frequencies from 34 to 66%in the D-02,BHP group,and from 13 to 21%in the segregating groups of the G3-0202 and G3-0201.The squash technique was used for both cytogenetic analyses.Different meiotic irregularities in maize chromosomes were detected,such as irregular association of 10%of chromosomes in metaphase 1,and agglomeration of chromatin in 100%of the cells.In addition,pollen viability was estimated by the staining technique with 1%acetocarmine dye,and it was found that the polyembryonic ones have pollen viability of 100%.In meiosis in prophase,I sub-phase diakinesis,ten pairs of bivalents were confirmed,confirming 2n=20,both in non-PEm and PEm maize,corroborating mating,and balanced segregation,without the presence of univalent or multivalent.In the chromosomal count carried out in cells in mitosis,only in the BHP-200 polyembryonic family was registered two out of twenty triploid plants.This condition of ploidy is atypical in maize,so it is recommended to analyze more plant

关键词： Zea mays irregular meiosis mitosis chromosomes chromatin polyploidy

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Highly divergent sympatric lineages of Leptotila verreauxi(Aves:Columbidae)suggest a secondary contact area in the Isthmus of Tehuantepec,Mexico

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Avian Research 2024年第1期15卷 12-21页

作者： Orlando j.Espinosa-Chávez Adolfo G.Navarro-sigüenza Hernando Rodríguez-Correa Luis A.sánchez-González Museo de Zoología“Alfonso L.Herrera” Depto.de Biología EvolutivaFacultad de CienciasUniversidad Nacional Autonoma de MexicoApdo.Postal 70-399CP 04510Ciudad de MexicoMexico Posgrado en Ciencias Biologicas Unidad de PosgradoEdificio D1◦PisoCircuito de PosgradosCiudad UniversitariaUniversidad Nacional Autonoma de MexicoCoyoacanCP 04510CDMXMexico Escuela Nacional de Estudios superiores Unidad Morelia Universidad Nacional Autonoma de Mexico.Antigua Carretera a Patzcuaro No.8701 Col.Ex Hacienda de San Jose de la HuertaC.P.58190MoreliaMichoacanMexico

Due to a complex geological and biotic history,the Isthmus of Tehuantepec(IT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland taxa.Widely distributed in the lowlands of the American continent,the White-Tipped Dove(Leptotila verreauxi)is a polytypic species with 13 recognized subspecies.Four of these have been recorded in Mexico,and the distribution of three abuts at the IT,suggesting a contact zone.To estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(ND2 and COI)and one n DNA(β-fibint 7)markers.We also used correlative ecological niche models(ENM)to assess whether ecological differences across the IT may have acted as a biogeographical boundary.We estimated paleodistributions during the Middle Holocene,Last Glacial Maximum and Last Interglacial,to evaluate the influence of climate changes on the distribution and demographic changes.Our results showed genetically distinct lineages that diverged approximately 2.5 million years ago.Climatic and ecological factors may have played a dual role in promoting differentiation,but also in the formation of a secondary contact zone in the southern IT.Our ecological niche comparisons indicated that the ecological niche of sympatric lineages at the IT are not identical,suggesting niches divergence;in addition,environmental niche models across the region indicated no abrupt biogeographic barriers,but the presence of regions with low suitability.These results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological niches.Also,the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions,suggest that secondary contact zones may be also maintained by climatic factors for the eastern group,but also by biotic interactions for the western group.

关键词： Biogeographical boundary Humid and dry forests Isthmus of Tehuantepec Phylogeography secondary contact

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sustained adenosine release:Revealing its impact on osteogenic signalling pathways of human mesenchymal stromal cells

Engineered Regeneration

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Engineered Regeneration 2024年第2期5卷 255-268页

作者： Hadi Hajiali jane McLaren Cristina Gonzalez-García salah Abdelrazig Dong-Hyun Kim Matthew j.Dalby Manuel salmerón-sánchez Felicity R.A.j.Rose school of Pharmacy Nottingham Biodiscovery InstituteUniversity of NottinghamNottinghamUK Healthcare Technologies Institute School of Chemical EngineeringUniversity of BirminghamBirminghamUK Centre for the Cellular Microenvironment University of GlasgowGlasgowUK Centre for Analytical Bioscience Advanced Materials&Healthcare Technologies DivisionSchool of PharmacyUniversity of NottinghamNottinghamUK Marine Microbiomics Program in BiologyDivision of Science and MathematicsNew York University Abu Dhabi(NYUAD)P.O.Box 129188Abu DhabiUnited Arab Emirates

Non-healing fractures,a global health concern arising from trauma,osteoporosis,and tumours,can lead to severe disabilities.Adenosine,integral to cellular energy metabolism,gains prominence in bone regeneration via adeno-sine A2 B receptor activation.This study introduces a controlled-release system for localized adenosine delivery,fostering human mesenchymal stromal cell(hMsC)differentiation into functional bone cells.The study investi-gates how the ratio of lactic acid to glycolic acid in microparticles can influence adenosine release and explores the downstream effects on gene expression and metabolic profiles of osteogenic differentiation in hMsCs cultured in growth and osteoinductive media.Insights into adenosine-modulated signalling pathways during MsC differenti-ation,with osteogenic factors,provide a comprehensive understanding of the pathways involved.Analysing gene expression and metabolic profiles unravels adenosine’s regulatory mechanisms in MsC differentiation.sustained adenosine release from microparticles induces mineralization,synergizing with osteogenic media supplements,showcasing the potential of adenosine for treating critical bone defects and metabolic disorders.This study high-lights the efficacy of a polymeric microparticle-based delivery system,offering novel strategies for bone repair.Unveiling adenosine’s roles and associated signalling pathways advances our comprehension of molecular mech-anisms steering bone regeneration,propelling innovative biomaterial,combined with metabolites,approaches for clinical use.

关键词： Adenosine release Osteogenic signalling pathways Human mesenchymal stromal cells Bone regeneration

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Biomass gasification,catalytic technologies and energy integration for production of circular methanol:New horizons for industry decarbonisation

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journal of Environmental sciences 2024年第6期140卷 306-318页

作者： Luis F.Bobadilla Lola Azancot Miriam González-Castañ Estela Ruíz-López Laura Pastor-Pérez Francisco j.Durán-Olivencia Runping Ye Katie Chong Paula HBlanco-sánchez Zenthao Wu Tomás R.Reina j.séA.Odriozola Departamento de Química Inorgánica e Instituto de Ciencia de Materiales de sevilla Centro Mixto CSIC-Universidad de SevillaAvda.Américo Vespucio 49Sevilla 41092Spain Departamento de Ingeniería Universidad Loyola AndalucíaAvda.de Las Universidades s/nSevilla 41704Spain Key Laboratory of jiangxi Province for Environment and Energy Catalysis School of Chemistry and Chemical EngineeringNanchang UniversityNanchang330031China Energy and Bioproducts Research Institute(EBRI) Aston UniversityBirminghamB47ETUnited Kingdom Department of Chemical and Process Engineering University of SurreyGuildfordGU27XHUnited Kingdom

The Intergovernmental Panel on Climate Change(IPCC)recognises the pivotal role of renewable energies in the future energy system and the achievement of the zero-emission target.The implementation of renewables should provide major opportunities and enable a more secure and decentralised energy supply system.Renewable fuels provide long-term solutions for the transport sector,particularly for applications where fuels with high energy density are required.In addition,it helps reducing the carbon footprint of these sectors in the long-term.Information on biomass characteristics feedstock is essential for scaling-up gasification from the laboratory to industrial-scale.This review deals with the transformation biogenic residues into a valuable bioenergy carrier like biomethanol as the liquid sunshine based on the combination of modified mature technologies such as gasification with other innovative solutions such as membranes and microchannel reactors.Tar abatement is a critical process in product gas upgrading since tars compromise downstream processes and equipment,for this,membrane technology for upgrading syngas quality is discussed in this paper.Microchannel reactor technology with the design of state-of-the-art multifunctional catalysts provides a path to develop decentralised biomethanol synthesis from biogenic residues.Finally,the development of a process chain for the production of(i)methanol as an intermediate energy carrier,(ii)electricity and(iii)heat for decentralised applications based on biomass feedstock flexible gasification,gas upgrading and methanol synthesis is analysed.

关键词： Biogenic residues Gasification Biomethanol Circular Economy Microreactors

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Background removal from global auroral images:Data-driven dayglow modeling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohma M.Madelaire K.M.Laundal j.P.Reistad s.M.Hatch s.Gasparini s.j.Walker Birkeland Centre for space science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by sunlight.Nightglow emissions and scattered sunlight can contribute to the background signal.To fully utilize such images in space science,background contamination must be removed to isolate the auroral signal.Here we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical harmonics.The approach is robust,flexible,and iteratively deselects outliers,such as auroral emissions.The final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the dayglow.We demonstrate the model by using the three far ultraviolet cameras on the Imager for Magnetopause-to-Aurora Global Exploration(IMAGE)mission.The method can be applied to historical missions and is relevant for upcoming missions,such as the solar wind Magnetosphere Ionosphere Link Explorer(sMILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

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Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.LEE s.CHANG j.LEE Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea school of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random inputs.The method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data set.In the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random inputs.This allows for avoiding repeated computations of invariant substructures while generating the input-output data set.Combining substructuring with static condensation further improves the computational efficiency of the reanalysis without losing accuracy.Consequently,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional inputs.The numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

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Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： N.IQBAL j.CHOI s.F.sHAH C.LEE s.LEE Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline Ni-rich LiNixMnyCo_(z)O_(2)(x≥0.8)(NMC)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of primary NMC particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more homogeneously.Besides,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress mitigation.This paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of NMC active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation Ni-rich LiNixMnyCo_(z)O_(2)(x>0.8)(NMC)

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Wettability,reactivity,and interface structure in Mg/Ni system

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journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： s.Terlicka N.sobczak Ł.Maj P.Darłak j.j.sobczak Institute of Metallurgy and Materials science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni substrates.For comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)procedure.The high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) atmosphere.During the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate couples.scanning and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified couples.It was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθs),followed by fast spreading and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test temperature.However,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.

关键词： Magnesium-based alloys sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

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Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by crystal plasticity finite element method

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journal of Materials science & Technology 2024年第2期169卷 53-67页

作者： Y.B.Zhang s.j.song F.Liu state Key Laboratory of solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPFE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive deformations.Accordingly,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase interface.It then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic correlation.Then by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and ductility.such hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

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Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/Cds heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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journal of Materials science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang Z.Yang s.Y.Yang Z.H.Dai Y.j.Liu j.H.Liao G.Y.Zhong Z.j.Xie Y.P.Fang s.s.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China school of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China school of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic reactions.Constructing photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor materials.Herein,a novel stable Ti_(3)C_(2)T_(x)MXene/Cds heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)Cds nanosheets on 2D MXene interface via a solvothermal method.The exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous catalyst.The unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the catalyst.Moreover,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of Cds.Under irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of Cds catalyst.This study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

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