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High CO_(2)permeation using a new Ce_(0.85)Gd_(0.15)O_(2-δ)-LaNiO_(3)composite ceramic–carbonate dual-phase membrane

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journal of Environmental Sciences 2024年第6期140卷 219-229页

作者： Daniela gonzález-Varela jFrancisco Gómez-García Gustavo Tavizon Heriberto Pfeiffer Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico Departamento de Física y Química Teórica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico 不详

This work shows the synthesis,characterization and evaluation of dense-ceramic membranes made of Ce_(0.85)Gd_(0.15)O_(2-δ)-LaNiO_(3)(CG-LN)composites,where the fluorite-perovskite ratio(CG:LN)was varied as follows:75:25,80:20 and 85:15 wt.%.Supports were initially characterized by XRD,SEM and electrical conductivity(using vacuum and oxygen atmospheres),to determine the composition,microstructural and ionic-electronic conductivity ***,supports were infiltrated with an eutectic carbonates mixture,producing the corresponding dense dual-phase membranes,in which CO_(2)permeation tests were ***,CO_(2)permeation experiments were performed from 900 to 700℃,in the presence and absence of oxygen(flowed in the sweep membrane side).Results showed that these composites possess high CO_(2)permeation properties,where the O_(2)addition significantly improves the ionic conduction on the sweep membrane ***,the GC80-LN20 composition presented the best results due to the following physicochemical characteristics:high electronic and ionic conductivity,appropriate porosity,interconnected porous channels,as well as thermal and chemical stabilities between the composite support and carbonate phases.

关键词： CO_(2)permeation Doped CeO_(2) LaNiO_(3) Impedance Ceramic carbonate membrane

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

The dark side of cyclooctatetraene(COT):Photophysics in the singlet states of“self-healing”dyes

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Chinese Chemical Letters 2024年第8期35卷 225-228页

作者： Supphachok Chanmungkalakul Syed Ali Abbas Abedi Federico j.hernández jianwei Xu Xiaogang Liu Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372Singapore Department of Chemistry University College LondonLondon WC1H 0AJUnited Kingdom Institute of Sustainability for Chemicals Energy and Environment(ISCE2)Agency for ScienceTechnology and Research(A^(∗)STAR)Jurong Island 627833Singapore

Cyclooctatetraene(COT)attachment to fluorophores(“self-healing”dyes)is known for quenching reac-tive triplet states via triplet-state energy transfer(TET),enhancing ***,COT’s impact on singlet states remains *** calculations reveal that COT induces energy transfer to dark states in deep blue dyes while promoting photoinduced electron transfer(PET)and intersystem crossing(ISC)in visible dyes,potentially compromising brightness and/or *** address this,we pro-pose the use of △E descriptor to optimize COT’s *** findings uncover COT’s multifaceted *** insights will guide the development of superior triplet state quenchers and photostable dyes.

关键词： Cyclooctatetraene Photostability Triplet state quencher Energy transfer Electron transfer

Mathematical modeling for estimating influenza vaccine efficacy:A case study of the Valencian Community,Spain.

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Infectious Disease Modelling 2024年第3期9卷 744-762页

作者： Carlos Andreu-Vilarroig Rafael j.Villanueva Gilberto gonzález-Parra Instituto de Matemática Multidisciplinar Universitat Politècnica de ValènciaValenciaSpain Department of Mathematics New Mexico TechSocorroNMUSA

Vaccine efficacy and its quantification is a crucial concept for the proper design of public health vaccination *** this work we proposed a mathematical model to estimate the efficacy of the influenza vaccine in a real-word *** particular,our model is a SEIR-type epidemiological model,which distinguishes vaccinated and unvaccinated ***,its dynamics is governed by a nonlinear system of ordinary differential equations,where the non-linearity arises from the effective contacts between susceptible and infected *** key aspects of this study is that we use a vaccine distribution over time that is based on real data specific to the elderly people in the Valencian Community and the calibration process takes into account that over one influenza season a specific proportion of the population becomes infected with *** consider the effectiveness of the vaccine,the model incorporates a parameter,the vaccine attenuation factor,which is related with the vaccine efficacy against the influenza *** this framework,in order to calibrate the model parameters and to obtain an influenza vaccine efficacy estimation,we considered the 2016–2017 influenza season in the Valencian Community,Spain,using the influenza reported cases of vaccinated and *** order to ensure the model identifiability,we choose to deterministically calibrate the parameters for different scenarios and we find the one with the minimum error in order to determine the vaccine *** calibration results suggest that the influenza vaccine developed for 2016–2017 influenza season has an efficacy of approximately 76.7%,and that the risk of becoming infected is five times higher for an unvaccinated individual in comparison with a vaccinated *** estimation partially agrees with some previous studies related to the influenza *** study presents a new integrated mathematical approach to study the influenza vaccine efficacy and gives f

关键词： Mathematical modeling Epidemiology SEIR Vaccine efficacy Influenza Valencian community

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 *** distributed in the lowlands of the American continent,the White-Tipped Dove(Leptotila verreauxi)is a polytypic species with 13 recognized *** of these have been recorded in Mexico,and the distribution of three abuts at the IT,suggesting a contact *** estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(ND2 and COI)and one n DNA(β-fibint 7)*** also used correlative ecological niche models(ENM)to assess whether ecological differences across the IT may have acted as a biogeographical *** estimated paleodistributions during the Middle Holocene,Last Glacial Maximum and Last Interglacial,to evaluate the influence of climate changes on the distribution and demographic *** results showed genetically distinct lineages that diverged approximately 2.5 million years *** 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 *** 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 *** results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological ***,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

MicroRNA-630:A promising avenue for alleviating inflammation in diabetic kidney disease

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World journal of Diabetes 2024年第7期15卷 1398-1403页

作者： javier Donate-Correa Ainhoa gonzález-Luis jésica Díaz-Vera juan Ramón hernandez-Fernaud Research Unit University Hospital Nuestra Señora de Candelaria(UHNSC)Santa Cruz de Tenerife 38010Spain Department of Biochemistry MicrobiologyCell Biology and GeneticsInstituto de Tecnologías BiomédicasUniversidad de La LagunaSanta Cruz de Tenerife 38000Spain

Diabetic kidney disease(DKD)is one of the complications of diabetes,affecting millions of people *** relentless progression of this condition can lead to kidney failure,requiring life-altering interventions such as dialysis or *** evidence suggests that immunologic and inflammatory elements play an important role in initiating and perpetuating the damage inflicted on renal tissues,exacerbating the decline in organ ***-like receptors(TLRs)are a family of receptors that play a role in the activation of the innate immune system by the recognition of pathogen-associated molecular *** data from in vitro and in vivo studies have highlighted the critical role of TLRs,mainly TLR2 and TLR4,in the pathogenesis of *** the diabetic milieu,these TLRs recognize diabetic-associated molecular signals,triggering a proinflammatory cascade that initiates and perpetuates inflammation and fibrogenesis in the diabetic *** non-traditional strategies targeting TLR signaling with potential therapeutic implications in DKD have been *** of these approaches is the use of microRNAs,small non-coding RNAs that can regulate gene *** editorial comments on the results of this approach carried out in a rat model of diabetes by Wu et al,published in this issue of the World journal of *** results of the experimental study by Wu et al shows that microRNA-630 decreased levels compared to non-diabetic ***,microRNA-630 exerted anti-inflammatory effects in the kidneys of diabetic rats through the modulation of *** findings indicate that the microRNA-630/TLR4 axis might represent a pathological mechanism of DKD and a potential therapeutic target capable of curbing the destructive inflammation characteristic of DKD.

关键词： Diabetes Diabetic kidney disease Inflammation Toll-like receptor 4 microRNA-630

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

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 joséA.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 *** implementation of renewables should provide major opportunities and enable a more secure and decentralised energy supply *** fuels provide long-term solutions for the transport sector,particularly for applications where fuels with high energy density are *** addition,it helps reducing the carbon footprint of these sectors in the *** on biomass characteristics feedstock is essential for scaling-up gasification from the laboratory to *** 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 *** 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 *** reactor technology with the design of state-of-the-art multifunctional catalysts provides a path to develop decentralised biomethanol synthesis from biogenic ***,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

Assessing above-ground biomass-functional diversity relationships in temperate forests in northern Mexico

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Forest Ecosystems 2021年第1期8卷 95-108页

作者： Benedicto Vargas-Larreta jorge Omar López-Martínez Edgar j.gonzález joséjavier Corral-Rivas Francisco javier hernández Tecnológico Nacional de México/Instituto Tecnológico de El Salto 34942 El SaltoDurangoMexico Cátedras CONACYT1582Av.Insurgentes SurCiudad de MéxicoMexico El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120 DurangoMexico

Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem *** patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue *** this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio ***:Using data from 414 permanent sample plots,covering 23%of temperate forest in the Sierra Madre Oriental(México),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWM)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged *** compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction ***,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWM traits throught spatial autoregressive ***:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged *** of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio ***-ground biomass was significantly correlated with three of the five functional diversity metrics,CWM maximum height and species *** results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity ***:Species richness,maximum height,functional richness,functional dispersion and Rao

关键词： Taxonomic diversity Functional diversity Complementarity hypothesis Mass-ratio hypothesis