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BaTiO3 solid solutions co-doped with gd3+ and Eu3+:Synthesis,structural evolution and dielectric properties

Journal of Rare Earths 2024年第10期 1920-1926页

作者： R.Martínez-López M.Pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández M.Reyes-Pérez M.i.Valenzuela-Carrillo g.Urbano-Reyes V.E.Reyes-Cruz g.i.dávila-pulido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo State Metallurgy and Materials department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

in this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(gd3+and Eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,gd2O3,and Eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xgd2xTi1-3xEu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XRd） and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of gd3+and Eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic Eu2TiO5and monoclinic BaTi2O5secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（LO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,gd,and Eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

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Role of hypoxia preconditioning in therapeutic potential of mesenchymal stem-cell-derived extracellular vesicles

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World Journal of Stem Cells 2022年第7期14卷 453-472页

作者： Victoria pulido-Escribano Bárbara Torrecillas-Baena Marta Camacho-Cardenosa gabriel dorado MaríaÁngeles gálvez-Moreno Antonio Casado-díaz Unidad de gestión Clínica de Endocrinología y Nutrición-gC17 Instituto Maimónides de Investigación Biomédica de CórdobaHospital Universitario Reina SofíaCórdoba 14004Spain dep.Bioquímica y Biología Molecular Campus Rabanales C6-1-E17Campus de Excelencia Internacional Agroalimentario(ceiA3)Universidad de CórdobaCIBERFESCórdoba 14071Spain

The use of mesenchymal stem-cells(MSC)in cell therapy has received considerable attention because of their *** properties include high expansion and differentiation in vitro,low immunogenicity,and modulation of biological processes,such as inflammation,angiogenesis and ***,the regenerative effect of MSC is partly due to their paracrine *** has prompted numerous studies,to investigate the therapeutic potential of their secretome in general,and specifically their extracellular vesicles(EV).The latter contain proteins,lipids,nucleic acids,and other metabolites,which can cause physiological changes when released into recipient ***,contents of EV can be modulated by preconditioning MSC under different culture *** them,exposure to hypoxia stands out;these cells respond by activating hypoxia-inducible factor(HiF)at low O_(2) *** has direct and indirect pleiotropic effects,modulating expression of hundreds of genes involved in processes such as inflammation,migration,proliferation,differentiation,angiogenesis,metabolism,and cell *** of these genes is reflected in the contents of secreted ***,numerous studies show that MSC-derived EV conditioned under hypoxia have a higher regenerative capacity than those obtained under *** this review,we show the implications of hypoxia responses in relation to tissue *** addition,hypoxia preconditioning of MSC is being evaluated as a very attractive strategy for isolation of EV,with a high potential for clinical use in regenerative medicine that can be applied to different pathologies.

关键词： Cell priming Extracellular vesicles Hypoxia Hypoxia-inducible factor Mesenchymal stemcells Regenerative medicine

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New insights into Plant isoprenoid Metabolism

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Molecular Plant 2012年第5期5卷 964-967页

作者： Pablo pulido Catalina Perello Manuel Rodriguez-Concepcion department of Molecular genetics Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB Campus UAB Bellaterra 08193 BarcelonaSpain

isoprenoids are a hugely diverse family of compounds derived from the C5 precursors isopentenyl diphosphate （iPP） and dimethylallyl diphosphate （dMAPP）. Although all free-living organisms synthesize isoprenoids, they are particularly abun- dant and diverse in plants, with tens of thousands structures known to date. The highest variety of plant isoprenoids are specialized （secondary） metabolites that participate in the interaction of plants with their environment. These include pigments, volatiles, and defense compounds, some of which have applications in industry and agriculture.

关键词： Metabolism insight Plant

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Extra dimensions and atomic transition frequencies

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Chinese Physics B 2008年第1期17卷 70-75页

作者：李志刚倪维斗 Antonio pulido Patón Center for gravitation and Cosmology Purple Mountain ObservatoryChinese Academy of Sciences

New unification theories predict large extra dimensions （LEds）. if that is the case, gravity would be stronger at short ranges than what Newtonian gravity predicts. LEds could also have effects at atomic level. in this paper we propose a new method to constrain the size of ‘gravity-only’ LEds by analysing how these LEds modify the energy of the atomic transitions 1s-2s and 2s-2p （Lamb shift）, in the particular case of the hydrogen and muonium atoms. We estimate these effects by using Bethe＇s non-relativistic treatment of Lamb shift. in the particular case of three LEds, which may be a candidate to explain the interaction mechanism of dark matter particles, we have found that current knowledge in atomic spectroscopy could constrain their sizes to less than 10 μm. Although our contributions do not reach the sensitivity given by SN1987a, they are still slightly better than recent constraints given by inverse Square Law tests of the Eoet-Wash group at Washington University, which gave R3 〈 36.6 μm.

关键词： large extra dimensions Lamb shift atomic spectroscopy

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NAdPH Thioredoxin Reductase C Controls the Redox Status of Chloroplast 2-Cys Peroxiredoxins in Arabidopsis thaliana

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Molecular Plant 2009年第2期2卷 298-307页

作者： Kerstin Kirchsteiger Pablo pulido Maricruz gonzalez Francisco Javier Cejudo instituto de Bioquimica Vegetal y Fotosintesis Universidad de Sevilla and CSIC Avda Americo Vespucio 49 41092-Sevilla Spain

Chloroplast 2-Cys peroxiredoxins （2-Cys Prxs） are efficiently reduced by NAdPH Thioredoxin reductase C （NTRC）. To investigate the effect of light/darkness on NTRC function, the content of abundant plastidial enzymes, Rubisco, glutamine synthetase （gS）, and 2-Cys Prxs was analyzed during two consecutive days in Arabidopsis wild-type and ntrc mutant plants. No significant difference of the content of these proteins was observed during the day or the night in wildtype and mutant plants. NTRC deficiency caused a lower content of fully reduced 2-Cys Prxs, which was undetectable in darkness, suggesting that NTRC is the most important pathway for 2-Cys Prx reduction, probably the only one during the night. Arabidopsis contains two plastidial 2-Cys Prxs, A and B, for which T-dNA insertion lines were characterized showing the same phenotype as wild-type plants. Two-dimensional gel analysis of leaf extracts from these mutants allowed the identification of basic and acidic isoforms of 2-Cys Prx A and B. in-vitro assays and mass spectrometry analysis showed that the acidic isoform of both proteins is produced by overoxidation of the peroxidatic Cys residue to sulfinic acid. 2-Cys Prx overoxidation was lower in the NTRC mutant. These results show the important function of NTRC to maintain the redox equilibrium of chloroplast 2-Cys Prxs.

关键词： Chloroplast peroxiredoxin NAdPH thioredoxin reductase C overoxidation thioredoxin Arabidopsis.

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Resource manipulation reveals flexible allocation rules to growth and reproduction in a Mediterranean evergreen oak

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Journal of Plant Ecology 2014年第1期7卷 77-85页

作者： Fernando pulido gerardo Moreno Eustolia garcía José J.Obrador Raúl Bonal Mario díaz grupo de investigación Forestal Ingeniería Forestal y del Medio NaturalUniversidad de ExtremaduraE-10600 PlasenciaCáceresSpain Colegio de Postgraduados Campus TabascoMX-86500 CárdenasTabascoMexico instituto de investigación en Recursos Cinegéticos (CSIC-UCLM-JCCM)University of Castilla-La ManchaCiudad RealSpain department of Biogeography and global Change(BCg-MNCN) Museo Nacional de Ciencias NaturalesCSICE-28006 MadridSpain

Aims in plants,resource allocation to growth and reproduction may depart from trade-off expectations if(i)investment in growth and reproduction relies on different resource pools,(ii)allocation to reproduction is dependent upon reaching some growth threshold or(iii)reproduction is developmentally linked to growth,both functions relying on the same resource *** examined the effects of enhanced resource level on patterns of resource allocation to growth and reproduction in holm oak(Quercus ilex ***),a Mediterranean evergreen *** in the experimental year(2003),we manipulated the amount of soil nutrients in autumn(to increase nutrient uptake during shoot elongation in the following spring)and soil water in summer(to increase water uptake during acorn growth).indicators of growth and male and female reproduction were estimated in the preexperimental(2002),experimental(2003)and post-experimental(2004)*** Findings Fertilized trees produced significantly longer shoots,but the number of female flowers per shoot was not affected by *** production of male catkins was also enhanced by *** did not affect the production of female flowers or abortion *** and female reproduction showed no consistent relationship in untreated trees,but resource addition elicited a growth-female reproduction trade-off in the experimental *** sign of this significant relationship changed in the post-experimental year,indicating the existence of lagged effects of resource manipulation on acorn ***,patterns of allocation to growth and reproduction varied as a function of sex,resource availability and year,a result consistent with extreme allocational plasticity in holm oak.

关键词： acorn abortion allocational plasticity dehesa growthreproduction trade-offs nutrient addition Quercus ilex resource allocation

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Robust disturbance Rejection Based Control with Extended-state Resonant Observer for Sway Reduction in Uncertain Tower-cranes

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international Journal of Automation and computing 2019年第6期16卷 812-827页

作者： Horacio Coral-Enriquez Santiago pulido-guerrero John Cortés-Romero Programa de ingeniería Mecatrónica Facultad de IngenieríaUniversidad de San Buenaventura sede BogotáCra.8H No 172-20 Edif.DBBogotáOf204Colombia departamento de ingeniería Eléctrica y Electrónica Facultad de IngenieríaUniversidad Nacional de Colombia sede BogotáCra.30 No 45-03 Edif.453BogotáOf222Colombia

in this paper, the problem of load transportation and robust mitigation of payload oscillations in uncertain tower-cranes is addressed. This problem is tackled through a control scheme based on the philosophy of active-disturbance-rejection. Here, a general disturbance model built with two dominant components: polynomial and harmonic, is stated. Then, a disturbance observer is formulated through state-vector augmentation of the tower-crane model. Thus, better performance of estimations for system states and disturbances is achieved. The control law is then formulated to actively reject the disturbances but also to accommodate the closed-loop system dynamics even under system uncertainty. The proposed control schema is validated via experimentation using a small-scale tower-crane,and compared with other relevant active disturbance rejection control(AdRC)-based techniques. The experimental results show that the proposed control scheme is robust under parametric uncertainty of the system, and provides improved attenuation of payload oscillations even under system uncertainty.

关键词： Active disturbance rejection control(AdRC) extended state observer(ESO) tower-crane control resonant observer disturbance observer linear matrix inequality

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Comparative Analysis of different Evaluation Functions for Protein Structure Prediction Under the HP Model

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Journal of Computer Science & Technology 2013年第5期28卷 868-889页

作者： Mario garza-Fabre Eduardo Rodriguez-Tello gregorio Toscano-pulido information Technology Laboratory CINVESTAV-Tamaulipas Km.5.5 Carretera Ciudad Victoria-Soto La Marina 87130 Ciudad Victoria Tamaulipas México

The HP model for protein structure prediction abstracts the fact that hydrophobicity is a dominant force in the protein folding process. This challenging combinatorial optimization problem has been widely addressed through metaheuristics. The evaluation function is a key component for the success of metaheuristics; the poor discrimination of the conventional evaluation function of the HP model has motivated the proposal of alternative formulations for this component. This comparative analysis inquires into the effectiveness of seven different evaluation functions for the HP model. The degree of discrimination provided by each of the studied functions, their capability to preserve a rank ordering among potential solutions which is consistent with the original objective of the HP model, as well as their effect on the performance of local search methods are analyzed. The obtained results indicate that studying alternative evaluation schemes for the HP model represents a highly valuable direction which merits more attention.

关键词： evaluation function protein structure prediction metaheuristics combinatorial optimization bioinformatics

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Magnetic Susceptibility and Natural gamma Radioactivity as indirect indicators of impurities in Limestones of the Sabinas Basin: Possible Relationships with the Sedimentation Environment

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Journal of geoscience and Environment Protection 2017年第10期5卷 77-91页

作者： José A. Batista Rodríguez Joaquín A. Proenza Fernández gloria i. dávila pulido Mitzué garza garcía itzayana Y. Zamora Medellín Universidad Autónoma de Coahuila Escuela Superior de Ingeniería Coahuila México departament de Cristallograia Mineralogia i Dipòsits Minerals Facultat de Geologia Universitat de Barcelona Barcelona Spain

This study presents an analysis of magnetic susceptibility and natural gamma radioactivity as indirect indicators of impurities in Cretaceous limestones of the Sabinas basin, as well as of the possible relation of these physical properties with the changes in the sedimentation environment. Both of these physical properties indicate changes in the degree of impurities and the mineralogical composition of this rock, principally in its organic matter and detritus content. Considering that the sedimentation environment determines the impurities in these rocks, possible environmental conditions at different levels of the Cretaceous were suggested using the magnetic susceptibility, total gamma radiation and potassium values, as well as the uranium and thorium concentration in the limestones. The analyses suggest variations in the depth of water table of the basin, which are mainly related to transgressions and marine regressions.

关键词： Magnetic Susceptibility Natural gamma Radioactivity Limestones Environment Sedimentation Sabinas Basin

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Córdoba乳腺断层融合筛查试验（CBTST）乳腺筛查间期癌：乳腺断层融合联合数字乳腺摄影与单纯数字乳腺断层成像的比较

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国际医学放射学杂志 2024年第05期 627-628页

作者： C.pulido Carmona S.Romero Martín J.L.Raya Povedano M.Cara garcía P.Font Ugalde E.Elías Cabot 张昕怡

目的比较数字乳腺断层摄影（dBT）+数字乳腺摄影（dM）与单纯dM筛查女性的乳腺筛查间期癌发病率及其特征的差异。方法比较Córdoba乳腺断层融合筛查试验

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