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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

CHARACTERISATION OF RATIONAL AND NURBS DEVELOPABLE SURFACES IN COmPUTER AIDED DESIGN

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Journal of Computational mathematics 2021年第4期39卷 556-573页

作者： leonardo Fernandez-Jambrina ETSI Navales Universidad Politecnica de Madrid28040-MadridSpain

In this paper we provide a characterisation of rational developable surfaces in terms of the blossoms of the bounding curves and three rational functions∧,m,ν.Properties of developable surfaces are revised in this *** particular,a closed algebraic formula for the edge of regression of the surface is obtained in terms of the functions∧,m,ν,which are closely related to the ones that appear in the standard decomposition of the derivative of the parametrisation of one of the bounding curves in terms of the director vector of the rulings and its *** is also shown that all rational developable surfaces can be described as the set of developable surfaces which can be constructed with a constant∧,m,ν.The results are readily extended to rational spline developable surfaces.

关键词： NURBS Bezier Rational Spline NURBS Developable surfaces

Central role of the LEAFY COTYLEDON1 transcription factor in seed development

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Journal of Integrative Plant Biology 2019年第5期61卷 564-580页

作者： leonardo Jo Julie m.Pelletier John J.Harada Department of Plant Biology and Plant Biology Graduate Group University of CaliforniaDavis USA

Seed development is a complex period of the flowering plant life *** fertilization,the three main regions of the seed,embryo,endosperm and seed coat,undergo a series of developmental processes that result in the production of a mature seed that is developmentally arrested,desiccated,and metabolically *** processes are highly coordinated,both temporally and spatially,to ensure the proper growth and development of the *** transcription factor,LEAFY COTYLEDON1(LEC1),is a central regulator that controls several aspects of embryo and endosperm development,including embryo morphogenesis,photosynthesis,and storage reserve ***,LEC1 regulates distinct sets of genes at different stages of seed *** its critical importance for seed development,an understanding of the mechanisms underlying LECi's multifunctionality is only beginning to be *** studies describe the roles of specific transcription factors and the hormones,gibberellic acid and abscisic acid,in controlling the activity and transcriptional specificity of LEC1 across seed ***,studies indicate that LEC1 acts as a pioneer transcript!on factor to promote epigenetic reprogramming during *** this review,we discuss the mechanisms that enable LEC1 to serve as a central regulator of seed development.

关键词： Seed development flowering plant seed development

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： leonardo Goliatt C.m.Saporetti L.C.Oliveira E.Pereira Department of Computational and Applied mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of Computational modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'TOC content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it relies on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the YuDong-Nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model selection,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning Evolutionary algorithms Geology

Exact recession velocity and cosmic redshift based on cosmological principle and Yang-mills gravity

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Chinese Physics C 2019年第10期43卷 105-111页

作者： leonardo Hsu Jong-Ping Hsu College of Education and Human Development University of MinnesotaMinneapolisMN 55455USA Department of Chemistry and PhysicsSanta Rosa Junior CollegeSanta RosaCA 95401USA Department of Physics University of Massachusetts DartmouthNorth DartmouthMA 02747-2300USA

Based on the cosmological principle and quantum Yang-mills gravity in the super-macroscopic limit, we obtain an exact recession velocity and cosmic redshift z, as measured in an inertial frame F≡F(t,x,y,z). For a matter-dominated universe, we have the effective cosmic metric tensor Gμν(t)=(B^2(t),-A^2(t),-A^2(t),-A^2(t)), A∝B∝t^1/2, where t has the operational meaning of time in F frame. We assume a cosmic action S≡Scos involving Gμν(t) and derive the ‘Okubo equation’ of motion, G^μν(t)■μS■νS-m^2=0, for a distant galaxy with mass m. This cosmic equation predicts an exact recession velocity, r=rH/[1/2+√1/4+r^2H^2/C0^2]me F. For small velocities, we have the usual Hubble's law r≈rH for recession velocities. Following the formulation of the accelerated Wu-Doppler effect, we investigate cosmic redshifts z as measured in F. It is natural to assume the massless Okubo equation, G^μν(t)■μψe■νψe=0, for light emitted from accelerated distant galaxies. Based on the principle of limiting continuation of physical laws, we obtain a transformation for covariant wave 4-vectors between and inertial and an accelerated frame, and predict a relationship for the exact recession velocity and cosmic redshift, z=[(1+Vr)/(1-Vr^2)1/2]-1, where Vr=r/Come F. These predictions of the cosmic model are consistent with experiments for small velocities and should be further tested.

关键词： Yang-mills gravity recession velocity speed limit of recession velocity redshift

DEVELOPABLE SURFACE PATCHES BOUNDED BY NURBS CURVES

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Journal of Computational mathematics 2020年第5期38卷 715-731页

作者： leonardo Fernandez-Jambrina Francisco Perez-Arribas ETSI Navales Universidad Polit´ecnica de Madrid28040-MadridSpain

In this paper we construct developable surface patches which are bounded by two rational or NURBS curves,though the resulting patch is not a rational or NURBS surface in *** is accomplished by reparameterizing one of the boundary *** reparameterization function is the solution of an algebraic *** the relevant case of cubic or cubic spline curves,this equation is quartic at most,quadratic if the curves are B´ezier or splines and lie on parallel planes,and hence it may be solved either by standard analytical or numerical methods.

关键词： NURBS B´ezier Rational,Spline NURBS Developable surfaces

Pennsylvanian glacimarine sedimentation in the Cushamen Formation,western North Patagonian massif

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Geoscience Frontiers 2018年第2期9卷 485-504页

作者： Paulo marcos Daniel A.Gregori leonardo Benedini mercedes Barros leonardo Strazzere Cecilia Pavón Pivetta Cátedra de Geofísica Departamento de GeologíaUniversidad Nacional del Sur and INGEOSURSan Juan 6708000 Bahía BlancaArgentina Cátedra de Geología Argentina Departamento de GeologíaUniversidad Nacional del Sur and INGEOSURSan Juan 6708000 Bahía BlancaArgentina Cátedra de Geología minera Departamento de GeologíaUniversidad Nacional del Sur and INGEOSURSan Juan 6708000 Bahía BlancaArgentina

The metasedimentary sequence of the Cushamen Formation in the western North Patagonian massif is540 m thick and comprises six sedimentary lithofacies associations related to a glacimarine *** of these lithofacies represent distal glacimarine environments, whereas another one was deposited in proximal glacimarine environments, and the last includes subglacial environments. The organization and configuration of these lithofacies associations represent the advance and retreat of the glacier masses. The maximum glacial advance is correlatable with the G2 glacial interval of the Pennsylvanian Pampa de Tepuel, Las Salinas and Valley Chico, formations of the Extraandean Chubut, and the southern part of Neuquen Cordillera. Contemporaneously, in southern Chile there are marine and glacimarine sediments. The chronostratigraphic relationships between the Silurian to Permian units allow five paleogeographic stages to be distinguished. The middle Silurian-late Devonian igneous rocks represent the first magmatic stage. The second stage, which is transitional to the first, is represented by a marine basin that includes the late Devonian-early Carboniferous Esquel and Rio Pescado formations and the Llanquihue Complex. The third stage(early-late Carboniferous) includes granitoids of the second magmatic event that partially overlapped the first magmatic igneous belt. The fourth stage belongs to the late Carboniferous sedimentation of the Cushamen and equivalent formations. The extended early Permian magmatism was the last Paleozoic event in the studied area.

关键词： Pennsylvanian Glacimarine sedimentation Cushamen Formation North Patagonian massif

Ethylene-inhibiting compound 1-mCP delays leaf senescence in cotton plants under abiotic stress conditions

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Journal of Integrative Agriculture 2015年第7期14卷 1321-1331页

作者： CHEN Yuan J T Cothren CHEN De-hua Amir m H Ibrahim leonardo Lombardini Department of Soil and Crop Sciences Texas A&M University College Station 77840USA Jiangsu Provincial Key Laboratory of Crops Genetics and Physiology Yangzhou University Department of Horticultural Sciences Texas A&M University College Station 77840USA

Cotton （Gossypium hirsutum L.） plants produce more ethylene when subjected to abiotic stresses, such as high temperatures and drought, which result in premature leaf senescence, reduced photosynthetic efficiency, and thus decreased yield. This study was conducted to test the hypothesis that the ethylene-inhibiting compound 1-methylcyclopropene （I-mCP） treatment of cotton plants can delay leaf senescence under high temperature, drought, and the aging process in controlled environ- mental conditions. Potted cotton plants were exposed to 1-mCP treatment at the early square stage of development. The protective effect of 1-mCP against membrane damage was found on older compared to younger leaves, indicating 1-mCP could lower the stress level caused by aging. Application of 1-mCP resulted in reduction of lipid peroxidation, membrane leakage, soluble sugar content, and increased chlorophyll content, in contrast to the untreated plants under heat stress, suggesting that 1-mCP treatment of cotton plants may also have the potential to reduce the effect of heat stress in terms of delayed senescence. Application of 1-mCP caused reductions of lipid peroxidation, membrane leakage, and soluble sugar content, together with increases in water use efficiency （WUE）, water potential, chlorophyll content, and fluorescence quantum efficiency, compared to the untreated plants under drought, suggesting that 1-mCP treatment of cotton plants may also have the ability to reduce the level of stress under drought conditions. In conclusion, 1-mCP treatment of cotton should have the potential to delay senescence under heat and drought stress, and the aging process. Additionally, 1-mCP is more effective under stress than under non-stress conditions.

关键词： 1-mCP ethylene membrane leakage lipid peroxidation chlorophyll fluorescence total soluble sugar

Direct observation of the CO_(2) formation and C–H consumption of carbon electrode in an aqueous neutral electrolyte supercapacitor by in-situ FTIR and Raman

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Journal of Energy Chemistry 2022年第8期31卷 488-496,I0013页

作者： murilo m.Amaral Victor Y.Yukuhiro Rafael Vicentini Alfredo C.Peterlevitz leonardo m.Da Silva Pablo Fernandez Hudson Zanin Advanced Energy Storage Division State University of Campinas13083-852Av.Albert Einsten 400CampinasSPBrazil Chemistry Institute State University of Campinas13083-970Josue de Castro StreetCampinasSPBrazil Department of Chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha and Mucuri’s ValleyRodovia MGT 367km 5835000Alto da Jacuba39100-000DiamantinaMGBrazil Center for Innovation on New Energies University of Campinas13083-841 CampinasSão PauloBrazil

Electrical double-layer capacitors(EDLCs)consist of energy storage devices that present high-power and moderate energy *** electrolyte and electrode physicochemical properties are crucial for improving their overall energy storage ***,the stability of the EDLCs’materials is the primary focus of this *** energy storage depends on the specific capacitance,and also on the square of the maximum capacitive cell voltage(UmCV).Thus,electrodes with high specific surface area(SSA)and electrolytes with excellent electrochemical stability are commonly reported in the *** electrolytes are safer and green devices compared to other organic-based *** the other hand,their UmCVis reduced compared to other electrolytes(e.g.,organic-based and ionic liquids).In this sense,spanning the UmCVfor aqueous-based electrolytes is a’hot topic’***,the lack of protocols to establish reliable UmCVvalues has culminated in the publishing of several conflicting ***,we confirm that multiwalled carbon nanotubes(mWCNTs)housed in cells degrade and produce CO_(2) under abusive polarisation *** is probed by employing electrochemical techniques,in-situ FTIR and in-situ Raman *** these considerations,the current study uses spectro-electrochemical techniques to support the correct determination of the electrode and electrolyte stability conditions as a function of the operating electrochemical parameters.

关键词： Electrode and electrolyte stabilities In-situ FTIR CO_(2)formation Carbon degradation Supercapacitor Aqueous electrolytes Carbon nanotubes