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Dipole and generalized oscillator strength derived electronic properties of an endohedral hydrogen atom embedded in a Debye-Huckel plasma

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Matter and Radiation at Extremes 2018年第5期3卷 227-242页

作者： c.martínez-flores R.cabrera-Trujillo Instituto de ciencias Físicas Universidad Nacional Autonoma de MexicoAp.Postal 43-8CuernavacaMorelos62251Mexico

We report electronic properties of a hydrogen atom encaged by an endohedral cavity under the influence of a weak plasma interaction. Weimplement a finite-difference approach to solve the Schrodinger equation for a hydrogen atom embedded in an endohedral cavity modeled by theWoods-Saxon potential with well depth V0, inner radius R0, thickness D, and smooth parameter g. The plasma interaction is described by aDebye-Hu¨ckel screening potential that characterizes the plasma in terms of a Debye screening length lD. The electronic properties of theendohedral hydrogen atom are reported for selected endohedral cavity well depths, V0, and screening lengths, lD, that emulate differentconfinement and plasma conditions. We find that for low screening lengths, the endohedral cavity potential dominates over the plasma interaction by confining the electron within the cavity. For large screening lengths, a competition between both interactions is observed. We assessand report the photo-ionization cross section, dipole polarizability, mean excitation energy, and electronic stopping cross section as function of lD and V0. We find a decrease of the Generalized Oscillator Strength (GOS) when the final excitation is to an s state as the plasma screeninglength decreases. For a final excitation into a p state, we find an increase in the GOS as the endohedral cavity well-depth increases. For the caseof the electronic stopping cross section, we find that the plasma screening and endohedral cavity effects are larger in the low-to-intermediateprojectile energies for all potential well depths considered. Our results agree well to available theoretical and experimental data and are afirst step towards the understanding of dipole and generalized oscillator strength dependent properties of an atom in extreme conditions encagedby an endohedral cavity immersed in a plasma medium.

关键词： Oscillator strengths Debye-Huckel plasma cavities Endohedral Energy loss Stopping power

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High pressure effects on the excitation spectra and dipole properties of Li, Be+, and B2+ atoms under confinement

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Matter and Radiation at Extremes 2020年第2期5卷 43-52页

作者： c.martinez-flores R.cabrera-Trujillo Departamento de Qu´ımica Universidad Aut´onoma Metropolitana IztapalapaSan Rafael Atlixco 186Col.VicentinaIztapalapaC.P.09340 M´exico D.F.Mexico Instituto de ciencias F´ısicas Universidad Nacional Aut´onoma de M´exicoAp.Postal 43-8CuernavacaMorelos62251Mexico Theoretische chemie Physikalisch-Chemisches InstitutUniversit¨at HeidelbergINF 22969120 HeidelbergGermany

Properties of atoms and molecules undergo significant changes when subjected to spatial *** study the excitation spectra of lithiumlike atoms in the initial 1s22s electronic configuration when confined by an impenetrable spherical *** implement Slater’s X-αmethod in Hartree–Fock theory to obtain the excitation *** that as the cavity size decreases,the total,2s,2p,and higher excited energy levels ***,we confirm the existence of crossing points between ns–np states for low values of the confinement radius such that the ns→np dipole transition becomes zero at that critical *** crossing points of the s–p states imply that instead of photon absorption,one observes photon emission for cavities with radius smaller than the critical ***,the dipole oscillator strength associated with the 2s→2p transition becomes negative,and for higher pressures,the 2s→3p dipole oscillator strength transition becomes larger than *** validate the completeness of the spectrum by calculating the Thomas–Reiche–Kuhn sum rule,as well as the static dipole polarizability and mean excitation energy of lithium-like *** find that the static dipole polarizability decreases and exhibits a sudden change at the critical pressure for the absorption-to-emission *** mean excitation energy increases as the pressure ***,as a consequence of the critical transition fromabsorption to emission,themean excitation energy becomes undetermined for higher pressures,with implications formaterial damage under extreme *** unconfined systems,our results show good to excellent agreement with data found in the literature.

关键词： transition. excitation dipole

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High pressure effects on the excitation spectra and dipole properties of Li, Be+, and B2+ atoms under confinement

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Matter and Radiation at Extremes 2020年第2期 17-26页

作者： c.martínez-flores R.cabrera-Trujillo Departamento de Química Universidad Autónoma Metropolitana Iztapalapa Instituto de ciencias Físicas Universidad Nacional Autónoma de Móxico Theoretische chemie Physikalisch-Chemisches Institut Universit?t Heidelberg

Properties of atoms and molecules undergo significant changes when subjected to spatial confinement. We study the excitation spectra of lithiumlike atoms in the initial 1s22s electronic configuration when confined by an impenetrable spherical cavity. We implement Slater's X-α method in Hartree–Fock theory to obtain the excitation spectrum. We verify that as the cavity size decreases, the total, 2s, 2p, and higher excited energy levels increase. Furthermore, we confirm the existence of crossing points between ns–np states for low values of the confinement radius such that the ns → np dipole transition becomes zero at that critical pressure. The crossing points of the s–p states imply that instead of photon absorption, one observes photon emission for cavities with radius smaller than the critical radius. Hence, the dipole oscillator strength associated with the 2s → 2p transition becomes negative, and for higher pressures, the 2s → 3p dipole oscillator strength transition becomes larger than unity. We validate the completeness of the spectrum by calculating the Thomas–Reiche–Kuhn sum rule, as well as the static dipole polarizability and mean excitation energy of lithium-like atoms. We find that the static dipole polarizability decreases and exhibits a sudden change at the critical pressure for the absorption-to-emission transition. The mean excitation energy increases as the pressure rises. However, as a consequence of the critical transition from absorption to emission, the mean excitation energy becomes undetermined for higher pressures, with implications for material damage under extreme conditions. For unconfined systems, our results show good to excellent agreement with data found in the literature.

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Addition of phenolic compounds to bread: antioxidant benefits and impact on food structure and sensory characteristics

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Food Production, Processing and Nutrition 2021年第1期3卷 314-325页

作者： Yesica A.czajkowska–González Emilio Alvarez–Parrilla Nina del Rocío martínez–Ruiz Alma A.Vázquez–flores Marcela Gaytán–martínez Laura Ade la Rosa Departament of chemical Biological Sciences Institute of Biomedical SciencesUniversidad Autónoma de Ciudad JuárezAnillo Envolvente del PRONAF y Estocolmos/nC.P.32310 Cd.JuárezMéxico Programa de Posgrado en Alimentos del centro de la República(PROPAc) Research and Graduate Studies in Food ScienceSchool of ChemistryUniversidad Autónoma de QuerétaroCentro UniversitarioCerro de las Campanas S/NC.P.76010 Santiago de QuerétaroMexico

The use of flours or phenolic extracts obtained from non-traditional sources or agri-food industry by-products has been a strategy used to formulate new bakery products with characteristics of a functional ***,phenolic compounds present great structural diversity,as well as the ability to interact in a complex way with the macromolecules that constitute the bread ***,the addition of these flours,extracts or pure compounds produces various effects on the microstructure of bread,and several of its sensory *** is mainly due to interactions between phenolic compounds and gluten *** objective of this review is to analyze some of the most recent published works on the addition of phenolic compounds in wheat bread to identify the type of positive and negative effects that have been observed and how they can be related to the physicochemical interactions between phenolic compounds and the macromolecules that constitute the food matrix,mainly *** effect of monomeric and polymeric phenolic compounds on the strength of these interactions and on the properties of dough and bread are discussed.

关键词： condensed tannins hydrolysable tannins phenolic acids gluten food rheology food texture protein-phenolic interactions disulfide bonds non-covalent interactions

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Recent Advances in Synthesis and Properties of Hybrid Halide Perovskites for Photovoltaics

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Nano-Micro Letters 2018年第4期10卷 167-200页

作者： c.c.Vidyasagar Blanca M.Muoz flores Víctor M.Jimnez Prez Universidad Autónoma de Nuevo León Facultad de Ciencias Químicas Ciudad Universitaria School of Basic Sciences and Research in chemistry Rani Channamma University

The progress made by the scientific community in emerging photovoltaic technologies over the past two decades has been outstanding. Numerous methods have been developed for the preparation of hybrid organic–inorganic perovskite solar cells. The power conversion efficiency has been up to 14% by a one-step vacuum deposition technique. A serious concern is the toxicity of the materials. In this review, several methods aimed at resolving these problems to some extent have been compiled, including eco-friendly synthesis. Further efficiency enhancements are expected following optimization, and a better fundamental understanding of the internal electron charge transfer, electron–hole diffusion to the corresponding layers, flexibility, and stability-dependent bandgaps is reported. This paper explores the green synthesis of organic–inorganic perovskites for industrialization. concerning the above facts, a simple low-cost model called‘‘dispersed photovoltaic cells' ' is presented.

关键词： Perovskites Solar cells Organic–inorganic perovskites Synthetic routes Fluorescence

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Stem cell therapy in inflammatory bowel disease: A promising therapeutic strategy?

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World Journal of Stem cells 2015年第2期7卷 343-351页

作者： Ana I flores Gonzalo J Gómez-Gómez ángeles Masedo-González M Pilar martínez-Montiel Servicio de Aparato Digestivo Hospital 12 de OctubreAvda. de Córdoba28041 MadridSpain

Inflammatory bowel diseases are inflammatory, chronic and progressive diseases of the intestinal tract for which no curative treatment is available. Research in other fields with stem cells of different sources and with immunoregulatory cells(regulatory T-lymphocytes and dendritic T-cells) opens up new expectations for their use in these diseases. The goal for stem cell-based therapy is to provide a permanent cure. To achieve this, it will be necessary to obtain a cellular product, original or genetically modified, that has a high migration capacity and homes into the intestine, has high survival after transplantation, regulates the immune reaction while not being visible to the patient's immune system, and repairs the injured tissue.

关键词： Mesenchymal stem cell Hematopoieticstem cell Inflammatory bowel disease crohn's disease Ulcerative colitis Amniotic fluid stem cells Inducedpluripotent stem cells Intestinal stem cells Endothelialprogenitor cells Tolerogenic immune cell therapies

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control Alternatives for Damping-Off in Tomato Seedling Production

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Phyton-International Journal of Experimental Botany 2019年第3期88卷 325-333页

作者： A.c.Michel-Aceves J.F.Díaz-Nájera R.Ariza-flores M.A.Otero-Sánchez R.Escobar-martínez c.H.Avendaño-Arrazate centro de Estudios Profesionales del colegio Superior Agropecuario del Estado de Guerrero Av.Vicente Guerrero No.81Colonia CentroIgualaGuerreroC.P.40000México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias(INIFAP)Campo Experimental IgualaCarr.Iguala-TuxpanKm.2.5 IgualaGuerreroMéxico INIFAP-campo Experimental Rosario Izapa.carr.Tapachula-cacahoatán Tuxtla chicoChiapasC.P.30870México

In two tomato genotypes,we assessed control alternatives for damping-off with combinations of chemical fungicides and native/commercial strains of biological *** treatments consisting of 19 levels of mixing products,chemical fungicides,native strains and commercial products from biological control agents,and untreated treatment were used onto Ramsés and Toro *** were distributed on an incomplete block design in divided plots arrangement,where genotypes constitute the larger ones and the 8-repetition mixed products,the smaller *** 180 mL of fungal complexes,made of spores and mycellium Fusarium-solani(2×106 UFc),Rhizoctonia-solani(1×106 UFc),Phytophthora-capsici(1×105 UFc)and Sclerotium-rolfsii(mycellium-sclerotia)on each seedling trays,made inoculation *** mixtures of(Bacillus spp.+Streptomyces spp.+Trichoderma spp.)+(Propamocarb+Fosetyl);(Bacillus spp.+Streptomyces spp.+Trichoderma spp.)+(Metalaxyl+chlorothalonil);Pseudomonas fluorescens+Streptomyces+Micromonospore+Sporideamium+Aminoacidos,Péptidos,carbohidratos)+(Propamocarb+Fosetyl);the native strain of Trichoderma asperellum+(Propamocarb+fosetil)and the native strains Trichoderma asperellum+Bacillus subtilis,diminished damping-off,prevented its appearance and had most significant agronomic *** contrast to this,combination of(Mancozeb)+(Free iodine)+(Metalaxyl+chlorothalonil)+(Methyl thiophanate)produced some toxicity in the *** addition,Ramsés presented the best agronomic parameters,while Toro had the utmost fresh and dry weight in root.

关键词： Trichoderma harzianum T.lignorum biological control

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Two novel mutations in theGAN gene causing giant axonal neuropathy

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World Journal of Pediatrics 2018年第3期14卷 298-304页

作者： Monica Irad Normendez-martínez Lucero Monterde-cruz Roberto martínez Magdalena Marquez-Harper Nayelli Esquitin-Garduno Margarita Valdes-flores Leonora casas-Avila Valeria Ponce de Leon-Suarez Viktor Javier Romero-Díaz Alberto Hidalgo-Bravo Medical Specialties Hospital Boulevard Milenio 130San Carlos la Roncha37660 LeonGuanajuatoMexico Department of Gene tics National Institute of R ehabilitationAvenue Mexico-Xochimilco 28914389 Me xico CityMexico Department ofHis tology School ofMedicineAutonomous University oft heS tate ofN uevo LeonMonterreyMexico

Background Giant axonal neuropathy (GAN) is a rare neurodegenerative disease transmitted in an autosomal recessive mode. This disorder presents motor and sensitive symptoms with an onset in early childhood. Progressive neurodegeneration makes the patients wheelchair dependent by the end of the second decade of life. Affected individuals do not survive beyond the third decade of life. Molecular analysis has identified mutations in the gene GAN in patients with this disorder. This gene produces a protein called gigaxonin which is presumably involved in protein degradation via the ubiquitin-proteasome system. However, the underlying molecular mechanism is not clearly understood yet. Methods Here we present the fi rst patient from Mexico with clinical data suggesting GAN. Sequencing of the GAN gene was carried out. changes in the nucleotide sequence were investigated for their possible impact on protein function and structure using the publicly available prediction tools PolyPhen-2 and PANTHER. Results The patient is a compound heterozygous carrying two novel mutations in the GAN gene. The sequence analy-sis revealed two missense mutations in the Kelch repeats domain. In one allele, a c>T transition was found in exon 9 at the nucleotide position 55393 (g.55393c>T). In the other allele, a transversion G>T in exon 11 at the nucleotide position 67471 (g.67471G>T) was observed. Both of the bioinformatic tools predicted that these amino acid substitutions would have a negative impact on gigaxonin's function. conclusion This work provides useful information for health professionals and expands the spectrum of disease-causing mutations in the GAN gene and it is the first documented case in Mexican population.

关键词： GAN Genetics Giant axonal neuropathy Incapacity Neurodegenerative

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Differential response of injured and healthy retinas to syngeneic and allogeneic transplantation of a clonal cell line of immortalized olfactory ensheathing glia:a double-edged sword

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Neural Regeneration Research 2025年第8期20卷 2395-2407页

作者： María Norte-Muñoz María Portela-Lomba Paloma Sobrado-calvo Diana Simón Johnny Di Pierdomenico Alejandro Gallego-Ortega Mar Pérez JoséMcabrera-Maqueda Javier Sierra Manuel Vidal-Sanz María Teresa Moreno-flores marta Agudo-Barriuso Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la SaludMurciaSpain Experimental Sciences Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain Anatomy Histology and Neuroscience DepartmentMedicine FacultyUniversidad Autónoma de MadridMadridSpain center of Neuroimmunology Service of NeurologyLaboratory of Advanced Imaging in Neuroimmunological DiseasesHospital Clínic of BarcelonaInstitut d’Investigacions Biomèdiques August Pi i Sunyer(IDIBAPS)and Universitat de BarcelonaBarcelonaSpain Medicine Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain

Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic ***,it is unknown whether olfactory ensheathing glia also have neuroprotective *** ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion ***,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve *** ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive *** and gene expression analyses were *** bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡ*** and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an *** axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 *** these retinas,microglial anatomical activation was higher than after optic nerve crush *** intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or ***,neuroprotection of axotomized retinal ganglion cells did not improve with these *** different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables.

关键词： cell therapy immune recognition major histocompatibility complex class II(MHcII) neuroprotection olfactory ensheathing glia retinal ganglion cells

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Limited long-distance dispersal success in a Western European fairy shrimp evidenced by nuclear and mitochondrial lineage structuring

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current Zoology 2020年第3期66卷 227-237页

作者： Paula c.RODRIGUEZ-flores Ernesto REcUERO Yolanda JIMEnez-RUIZ Mario GARcIA-PARIS Museo Nacional de ciencias Naturales(MNcN-cSIc) Jose Gutierrez Abascal2Madrid 28006Spain centre d'Estudis Avanqats de Blanes(cEAB-cSIc) C.d'Acces Cala Sant Francesc 14Blanes 17300Spain

Anostraca are known by their ability for long-distance dispersal,but the existence in several species of deep,geographically structured mtDNA lineages suggests their populations are subjected to allopatric differentiation,isolation,and prevalence of local scale *** stagnalis is one of the most widespread species of Anostraca and previous studies revealed an unclear geographical pattern of mtDNA genetic ***,we analyze populations from the Iberian and Italian Peninsulas,central Europe,and Scandinavia,with the aim to characterize the patterns of genetic diversity in a spatio-temporal framework using mtDNA and nuclear markers to test gene flow among close *** these aims we built a time-calibrated phylogeny and carried out Bayesian phylogeographic analyses using a continuous diffusion *** results indicated that *** presents a deeply structured genetic diversity,including 7 ancient lineages,some of them even predating the *** Iberian Peninsula harbors high diversity of lineages,with strong isolation and recent absence of gene flow between *** at local scale seems to be the prevailing dispersal mode of ***,which exhibits a pattern of isolation-bydistance in the Iberian *** remark the vulnerability of most of these lineages,given the limited known geographic distribution of some of them,and the high risk of losing important evolutionary potential for the species.

关键词： allopatric fragmentation Anostraca crustacea nuclear markers Pleistocene phylogeography

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