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Neural Regeneration Research 2024年第4期19卷 713-714页

作者： Rafael Simó Cristina hernández Diabetes and Metabolism Research Unit Vall d’Hebron Research Institute(VHIR) Department of Medicine Autonomous University of Barcelona Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas(CIBERDEM) Instituto de Salud CarlosⅢ(ICSⅢ)

Retinal neurodegeneration plays a significant role in the pathogenesis of diabetic retinopathy(DR),the leading cause of preventable *** fact,the American Diabetes Association has defined DR as a highly specific neurovascular complication(Solomon et al.,2017).Therefore,it is no longer acceptable to consider DR as merely a microvascular *** this regard,the term diabetic retinal disease(DRD)has been proposed as a broader term comprising microangiopathy and ***,there are currently no treatments available that directly target the neurodegenerative changes of *** paper will give new insights into the translational research in this field with particular emphasis on glucagon-like peptide 1/dipeptidyl peptidase IV(GLP-1/DPP-IV)inhibitors.

关键词： neurodegeneration ocular insight

AN OPTImaL coNTROL PROBLEM FOR A LOTKA-VOLTERRA coMPETITION MODEL WITH CHEMO-REPULSION

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Acta mathematica Scientia 2024年第2期44卷 721-751页

作者： Diana I.hernÁndez Diego A.RUEDA-GOMEZ Élder J.VILLAMIZAR-ROA Universidad Industrial de Santander Escuela de MatemáticasA.A.678BucaramangaColombia

In this paper we study a bilinear optimal control problem for a diffusive Lotka-Volterra competition model with chemo-repulsion in a bounded domain of ℝ^(ℕ),N=2,*** model describes the competition of two species in which one of them avoid encounters with rivals through a chemo-repulsion *** prove the existence and uniqueness of weak-strong solutions,and then we analyze the existence of a global optimal solution for a related bilinear optimal control problem,where the control is acting on the chemical ***,we derive first-order optimality conditions for local optimal solutions using the Lagrange multipliers ***,we propose a discrete approximation scheme of the optimality system based on the gradient method,which is validated with some computational experiments.

关键词： Lotka-Volterra chemo-repulsion optimal control optimality conditions

Deep optics preconditioner for modulation-free pyramid wavefront sensing

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Photonics Research 2024年第2期12卷 301-312页

作者： FELIPE GUZMÁN JORGE TAPIA CAMILO WEINBERGER NIcoLÁS hernÁndez JORGE BACCA BENOIT NEICHEL ESTEBAN VERA School of Electrical Engineering Pontificia Universidad Católica de Valparaı´soValparaı´soChile Department of Systems Engineering Universidad Industrial de SantanderBucaramangaColombia Laboratoire d’Astrophysique de marseille MarseilleFrance

The pyramid wavefront sensor(PWFS)can provide the sensitivity needed for demanding adaptive optics applications,such as imaging exoplanets using the future extremely large telescopes of over 30 m of diameter(D).However,its exquisite sensitivity has a limited linear range of operation,or dynamic range,although it can be extended through the use of beam modulation—despite sacrificing sensitivity and requiring additional optical *** by artificial intelligence techniques,this work proposes to train an optical layer—comprising a passive diffractive element placed at a conjugated Fourier plane of the pyramid prism—to boost the linear response of the pyramid sensor without the need for cumbersome *** develop an end-2-end simulation to train the diffractive element,which acts as an optical preconditioner to the traditional least-square modal phase estimation *** results with a large range of turbulence conditions show a noticeable improvement in the aberration estimation performance equivalent to over 3λ∕D of modulation when using the optically preconditioned deep PWFS(DPWFS).Experimental results validate the advantages of using the designed optical layer,where the DPWFS can pair the performance of a traditional PWFS with 2λ∕D of *** and adding an optical preconditioner to the PWFS is just the tip of the iceberg,since the proposed deep optics methodology can be used for the design of a completely new generation of wavefront sensors that can better fit the demands of sophisticated adaptive optics applications such as ground-to-space and underwater optical communications and imaging through scattering media.

关键词： process optics pyramid

Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico,Tamaulipas state,Mexico:implication for provenance

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Journal of Palaeogeography 2024年第3期13卷 375-400页

作者： mayank Shukla Sanjeet K.Verma mayla A.Ramos-Vázquez John S.Armstrong-Altrin Karla R.hernández-martínez Sumit Mishra Vivek P.malviya Héctor hernández-Mendoza Posgrado de la Division de Geociencias Aplicadas Instituto Potosino de Investigacion Científica y Tecnologica(IPICYT)Camino a la Presa San José2055San Luis Potosí78216Mexico Division de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnologica(IPICYT)Camino a la Presa San Jose 2055San Luis Potosí78216Mexico Universidad Nacional Autonoma de México Instituto de Ciencias del Mar y LimnologíaUnidad de ProcesosOceanicos y CosterosCiudad UniversitariaCiudad de México 04510Mexico Department of marine Sciences Bharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Instituto de Geociencias Universidad Nacional Autonoma de MéxicoBoulevard Juriquilla 300176230JuriquillaQueretaroMexico Department of Applied Geology Dr.Harisingh Gour Central UniversitySagar470002Madhya PradeshIndia Instituto de Investigacion de Zonas Desérticas Universidad Autònoma de San Luis PotosíAltair 200CP 78377San LuisS.L.P.Mexico Universidad del Centro de Mexico Capitán Caldera 75CP 78250San LuisS.L.P.Mexico

Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of *** main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach *** sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and *** beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic *** chemical index of weathering(CIW’)indicates intense weathering in the source *** quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical *** features such as fractures,pits,percussion marks,abrasion fatigue,and V-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian *** chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine *** mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine *** and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),Sierra madre Oriental(SMOr)and Oaxaquia *** major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.

关键词： Beach sediments Geochemistry Mineralogy Provenance Tamaulipas Tectonic setting

Diplopoda in the world fossil record

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Zoological Systematics 2024年第3期49卷 185-245页

作者： Michelle Álvarez-Rodríguez francisco Riquelme Miguel hernández-Patricio Fabio Cupul-magaña Laboratorio de Sistemática Molecular Escuela de Estudios Superiores del JicareroUniversidad Autónoma del Estado de MorelosC.P.62909JojutlaMorelosMexico MMRN Centro de Investigaciones BiológicasUniversidad Autónoma del Estado de MorelosC.P.62209CuernavacaMorelosMexico Unafíliate Centro Universitario de la costa Universidad de GuadalajaraC.P.48280Puerto VallartaJaliscoMexico

We present a comprehensive catalog with an updated database of the fossil record of Diplopoda in the *** data was collected from descriptions and reports published from 1854 to the *** also include new records from Mexican amber(Upper Oligocene-Lower Miocene),counting 83 unknown fossil inclusions,with the first records of the orders Polyxenida,Platydesmida,and Julida,as well as the families Sphaeriodesmidae and Trichopolydesmidae within *** to our results,Diplopoda counts 413 records featuring 299 distinct taxa ranging from the Middle Silurian to the Upper Pleistocene,representing three subclasses,two subterclasses,six superorders,25 orders,15 superfamilies,55 families,93 genera,and 161 fossil *** date,no fossils of the order Siphonocryptida have been *** fossil record extends over three geological eras:the Paleozoic,with 161 taxa,including 97 species;the Mesozoic,with 53 taxa and 22 species;and the Cenozoic,with 85 taxa and 42 *** referred material shows different forms of fossil *** comprises 123 impressions,99 compressions,26 ichnites,predominantly from Paleozoic and Mesozoic sediments,and 165 amber inclusions from late Mesozoic and Cenozoic ***,this catalog allows us to estimate the size and taxonomic composition of Diplopoda in the fossil record worldwide.

关键词： Millipedes Paleozoic Mesozoic Cenozoic new records catalog

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the coVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso Iván Y.hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the coVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the New *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： coVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

Attaching CFgroups to organic molecules using trifluoroacetates via ion-shielding photoelectrocatalysis

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Science China Chemistry 2024年

作者： Paula Visiedo-Jiménez francisco Juliá-hernández Departamento de Química Inorgánica Facultad de Química Universidad de MurciaCampus de Espinardo

Fluorinated molecules play a protagonist role in pharmaceuticals, agrochemicals, and materials. The incorporation of fluoroalkyl groups into organic compounds provides them with unique chemical properties that are key...

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Metal-modulated epitaxy of Mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto hernández-Gutiérrez Enrique Campos-González Máximo López-López Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with Mg by plasma-assisted molecular beam epitaxy(PAMBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(MME)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBL)in LED *** varied the Al composition in the EBL from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SILVAco *** results from this study highlight the importance and capability of producing high-quality Mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-LED EBL simulation

Dendritic spine degeneration:a primary mechanism in the aging process

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Neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo Flores Leonardo Aguilar-hernández Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de Ciencias Forenses(INCIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto Nacional de Medicina Genómica(INMEGEN) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(mayer et al., 2022;Aguilarhernández et al., 2023).

关键词： aging process stress

Resilience to structural and molecular changes in excitatory synapses in the hippocampus contributes to cognitive function recovery in Tg2576 mice

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Neural Regeneration Research 2024年第9期19卷 2068-2074页

作者： Carolina Aguado Sara Badesso Josémartínez-hernández Alejandro martín-Belmonte Rocío Alfaro-Ruiz Miriam Fernández Ana Esther Moreno-martínez mar Cuadrado-Tejedor Ana García-Osta Rafael Luján Synaptic Structure Laboratory Instituto de Investigación en Discapacidades Neurológicas(IDINE)Department of Medical SciencesFacultad de MedicinaUniversidad de Castilla-La ManchaCampus BiosanitarioAlbaceteSpain Gene Therapy for Neurological Disease Program Center for Applied Medical Research(CIMA)University of NavarraInstituto de Investigación Sanitaria de Navarra(IdiSNA)PamplonaSpain Pharmacology Unit Department of Pathology and Experimental TherapeuticsFaculty of Medicine and Health SciencesInstitute of NeurosciencesUniversity of BarcelonaBarcelonaSpain Neuropharmacology and Pain Group Neuroscience ProgramInstitut d’InvestigacióBiomèdica de BellvitgeIDIBELLL’Hospitalet de LlobregatSpain Department of Pathology Anatomy and PhysiologySchool of MedicineUniversity of NavarraPamplonaSpain UniversitéGrenoble Alpes Grenoble Institut des NeurosciencesGrenobleFrance

Plaques of amyloid-β(Aβ)and neurofibrillary tangles are the main pathological characteristics of Alzheimer’s disease(AD).However,some older adult people with AD pathological hallmarks can retain cognitive *** the factors that lead to this cognitive resilience to AD offers promising prospects for identifying new therapeutic *** hypothesis focuses on the contribution of resilience to changes in excitatory synapses at the structural and molecular levels,which may underlie healthy cognitive performance in aged AD *** the Morris Water maze test,we selected resilient(asymptomatic)and cognitively impaired aged Tg2576 *** the enzyme-linked immunosorbent assay showed similar levels of Aβ42 in both experimental groups,western blot analysis revealed differences in tau pathology in the pre-synaptic supernatant *** further investigate the density of synapses in the hippocampus of 16-18 month-old Tg2576 mice,we employed stereological and electron microscopic *** findings indicated a decrease in the density of excitatory synapses in the stratum radiatum of the hippocampal CA1 in cognitively impaired Tg2576 mice compared with age-matched resilient Tg2576 and non-transgenic ***,through quantitative immunoelectron microscopy in the hippocampus of impaired and resilient Tg2576 transgenic AD mice,we uncovered differences in the subcellular localization of glutamate ***,the density of GluA1,GluA2/3,and mGlu5 in spines and dendritic shafts of CA1 pyramidal cells in impaired Tg2576 mice was significantly reduced compared with age-matched resilient Tg2576 and non-transgenic ***,the density of GluA2/3 in resilient Tg2576 mice was significantly increased in spines but not in dendritic shafts compared with impaired Tg2576 and non-transgenic *** subcellular findings strongly support the hypothesis that dendritic spine plasticity and synaptic machinery in the hippocampus play cr

关键词： aging Alzheimer´s disease cognitive hippocampus immunoelectron microscopy resilience synapse