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Journal of environmental Sciences 2025年第3期149卷 535-550页

作者： yocelin B.González-González Fernando Plascencia-Hernández Rubén Mendoza-Cruz Heriberto Pfeiffer instituto de investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510CdMxMexico

Li_(6)ZnO_(4)was chemically modified by nickel addition,in order to develop different compositions of the solid solution Li_(6)Zn_(1-x)Ni_(x)O_(4).These materials were evaluated bifunctionally;analyzing their CO_(2)capture performances,aswell as on their catalytic properties for H_(2)production via dry reforming of methane(DRM).The crystal structures of Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution samples were determined through X-ray diffraction,which confirmed the integration of nickel ions up to a concentration around 20 mol%,meanwhile beyond this value,a secondary phase was *** results were supported by XPS and TEM ***,dynamic and isothermal thermogravimetric analyses of CO_(2)capture revealed that Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution samples exhibited good CO_(2)chemisorption efficiencies,similarly to the pristine Li_(6)ZnO_(4)chemisorption trends ***,a kinetic analysis of CO_(2)isothermal chemisorptions,using the Avrami-Erofeev model,evidenced an increment of the constant rates as a function of the Ni *** Ni^(2+)ions incorporation did not reduce the CO_(2)capture efficiency and kinetics,the catalytic properties of thesematerialswere evaluated in the DRM *** demonstrated that nickel ions favored hydrogen(H_(2))production over the pristine Li_(6)ZnO_(4)phase,despite a second H2 production reaction was determined,methane ***,Li_(6)Zn_(1-x)Ni_(x)O_(4)ceramics can be employed as bifunctional materials.

关键词： Dry reforming of methane(DRM) CO_(2)chemisorption H_(2)production Solid solution Li_(6)ZnO_(4)

Atmospheric chemistry of trifluorodicarbonyls initiated by Cl atoms:Reactivity trends,mechanism,and acid formation yields

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Journal of environmental Sciences 2025年第5期151卷 12-25页

作者： Pedro L.Lugo Vianni G.Straccia Cynthia B.Rivela Mariano A.Teruel María B.Blanco Laboratorio Universitario de Química y Contaminación del Aire(L.U.Q.C.A) Instituto de Investigaciones en Fisicoquímica de Córdoba(I.N.F.I.Q.C.)Dpto.de Fisicoquímica.Facultad de Ciencias QuímicasUniversidad Nacional de Córdoba.Ciudad Universitaria5000 CórdobaArgentina Institute for Atmospheric and environmental Research University of WuppertalDE-42097 WuppertalGermany

Rate coefficients of the gas-phase reactions of Cl atoms with a series of fluorinated diketones(FDKs):CF_(3)C(O)CH_(2)C(O)CH_(3)(TFP),CF_(3)C(O)CH_(2)C(O)CH_(2)CH_(3)(TFH)and CF_(3)C(O)CH_(2)C(O)CH(CH_(3))2(TFMH),have been measured at(298±2)K and under atmospheric *** experiments were performed using the relative-rate method with a GC-FID detection *** different determinations and references used,the following rate coefficients were obtained(in cm3/(molecule·sec)):k_(4)(TFP+Cl)=(1.75±0.21)×10^(−10),k_(5)(TFH+Cl)=(2.05±0.23)×10^(−10),k_(6)(TFMH+Cl)=(2.71±0.34)×10^(−10).Reactivity trends of FDKs were discussed and Free energy Relationships analysis was *** expression lgkOH=1.68 lgkCl+5.71 was obtained for the reactivity of the studied FDKs together with similar unsaturated VOCs with Cl and OH radicals Additionally,acetic acid(CH_(3)C(O)OH)and trifluoroacetic acid(CF_(3)C(O)OH)were positively identified and quantified as degradation products using in situ FTIR *** to the identified products,atmospheric chemical mechanisms were *** atmospheric implications of the studied reactions were assessed by the estimation of the tropospheric lifetimes of TFP,TFH,and TFMH concerning their reaction with Cl atoms to be 48,41,and 31 hours,*** relatively short residence in the atmosphere of the fluorocarbons studied will have a local/regional impact with restricted *** warming potential(GWP(20 yr))calculated for the studied fluoro diketones were 0.014,0.003 and 0.001 for TFP,TFH and TFMH,respectively with a negligible contribution to the greenhouse effect.

关键词： Fluorinated diketones Kinetics SPME-GC-FID FTIR in situ SAR Free energy relationships

Assessment of skeletal muscle alterations and circulating myokines in metabolic dysfunction-associated steatotic liver disease:A crosssectional study

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World Journal of Gastroenterology 2025年第7期31卷 63-73页

作者： yolanda Real Martinez Carlos Ernesto Fernandez-Garcia Esther Fuertes-yebra Mario Calvo Soto Angela Berlana Vicente Barrios Maria Caldas Leticia Gonzalez Moreno Luisa Garcia-Buey Begoña Molina Baena Miguel Sampedro-Nuñez Maria J Beceiro C García-Monzón Águeda González-Rodríguez Servicio Aparato Digestivo Hospital Universitario La PrincesaInstituto de Investigación Sanitaria La PrincesaUniversidad Autónoma de MadridMadrid 28006Spain Unidad de Investigación Hospital Universitario Santa CristinaInstituto de Investigación Sanitaria La PrincesaMadrid 28009Spain department of endocrinology Department of PediatricsHospital Infantil Universitario Niño JesúsInstituto de Investigación La PrincesaMadrid 28009Spain Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición Instituto de Salud Carlos IIIMadrid 28029Spain Servicio de endocrinología y Nutrición Hospital Universitario La PrincesaInstituto de Investigación Sanitaria La PrincesaUniversidad Autónoma de MadridMadrid 28006Spain instituto de investigaciones Biomédicas Sols-Morreale(IIBM) CSIC-UAMMadrid 28029Spain Centro de Investigación Biomédica en Red de Diabetes y enfermedades Metabólicas Asociadas Madrid 28029Spain

BACKGROUND Skeletal muscle alterations(SMAs)are being increasingly recognized in patients with metabolic dysfunctionassociated steatotic liver disease(MASLD)and appear to be associated with deleterious outcomes in these ***,their actual prevalence and pathophysiology remain to be *** To determine the prevalence of SMAs and to assess the significance of circulating myokines as biomarkers in patients with *** Skeletal muscle strength and muscle mass were measured in a cross-sectional study in a cohort of 62 patients fulfilling MASLD criteria,recruited from the outpatient clinics of a tertiary level *** degree of fibrosis and liver steatosis was studied using abdominal ultrasound and transitional *** and metabolic characteristics as well as serum levels of different myokines were also determined in the MASLD *** analysis was performed comparing results according to liver fibrosis and *** No significant differences were found in both skeletal muscle strength and skeletal muscle mass in patients with MASLD between different stages of liver ***,serum levels of fibroblast growth factor-21(FGF21)were significantly higher in patients with MASLD with advanced hepatic fibrosis(F3-F4)than in those with lower fibrosis stages(F0-F2)(197.49±198.27 pg/mL vs 95.62±83.67 pg/mL;P=0.049).In addition,patients with MASLD with severe hepatosteatosis(S3)exhibited significantly higher serum levels of irisin(1116.87±1161.86 pg/mL)than those with lower grades(S1-S2)(385.21±375.98 pg/mL;P=0.001).CONCLUSION SMAs were uncommon in the patients with MASLD *** serum levels of irisin and FGF21 were detected in patients with advanced liver steatosis and fibrosis,respectively,with potential implications as biomarkers.

关键词： Skeletal muscle alterations Myokines Metabolic dysfunction-associated steatotic liver disease Liver fibrosis Hepatosteatosis

Touristic urbanization and greening of coastal dune fields:A long-term assessment of a temperate sandy barrier of Argentina

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Journal of Geographical Sciences 2025年第1期35卷 206-230页

作者： GARZO Pedro Andrés DADON JoséRoberto ISLA Federico Ignacio instituto de investigaciones Marinas y Costeras(IIMyC-CONICET/UNMDP) Av.Juan B.Justo 2550Mar del Plata7600Buenos AiresArgentina instituto de Geología de Costas y del Cuaternario Dr.enrique J.Schnack(IGCC-CIC/UNMDP) Funes 3350Mar del Plata7600Buenos AiresArgentina Facultad de Arquitectura Diseño y UrbanismoCentro de Investigaciones Gestión de Espacios Costeros(GEC-FADU/UBA)Universidad de Buenos AiresIntendente Güiraldes 2160Pabellón ⅢPiso 4Ciudad Autónoma de Buenos Aires1428Argentina Consejo Nacional de investigaciones Científicas y Técnicas(CONICET) Buenos AiresArgentina

Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the ***,a century ago,they were considered hazardous environments due to their great dynamic *** a result,stabilization practices were considered *** systematic introduction of fast-growing exotic trees helped stabilize the sand,making it easier for tourism urbanization to take place,but also leading to erosion *** paper aims to assess long-term changes in vegetation cover over a large temperate barrier in *** complex region includes urban resorts,afforestation zones,and protected areas.A GIS-based geospatial analysis was conducted using a large satellite database(>350 images),and the future evolution of the vegetation was *** results revealed two primary spatiotemporal patterns associated with a gradual expansion of vegetation cover,accompanied by a concurrent reduction in sandy *** 1986,the dune area comprised 75%more surface than vegetation,whereas in 2021,it represented 60%less than ***,the 2050 scenario suggests a potential 40%reduction of dunes in certain *** is necessary to enhance management actions aimed at maintaining dune mobility and ensuring local and regional sediment ***-term management strategies must focus on restoring native plant communities and controlling invasive species,and avoiding new dune fixation initiatives based on the introduction of exotic species.

关键词： nature reserves afforestation sediment balance dune management NDVI

Plumbing System of Hunga Tonga Hunga Ha'apai Volcano

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Journal of Earth Science 2023年第3期34卷 706-716页

作者： Román Alvarez Miguel Camacho instituto de investigaciones en matemáticas aplicadas y en sistemas(IIMAS) Universidad Nacional Autónoma de MéxicoCoyoacán CDMX 04510Mexico Posgrado en Ciencias de la Tierra Universidad Nacional Autónoma de MéxicoCoyoacán CDMX 04510Mexico

The Hunga Tonga Hunga Ha’apai submarine volcano has experienced repeated eruptions in the latest *** recent one,in January 2022,released an enormous amount of energy inducing global perturbations,as tsunamis and atmospheric *** structure of the volcano is poorly understood,especially its internal ***-seated magmatic connections are difficult to define or *** use a high-resolution gravity data set obtained via satellite to calculate the Bouguer anomaly over its structure,to perform a preliminary exploration of its *** 3D gravity inversions,we find a complex plumbing system with various exhaust trajectories and multiple surface pockets of low-density material within the volcanic edifice;some appear to be associated with ring *** is in line with the report of the 2009 eruption,described as beginning from multiple *** found no signs of a magma chamber within 6 km depth,although several volcanic conduits are identified from such depth to the *** variations occur within a plumbing conduit or may vary from one conduit to another in the same *** models yield quantitative estimates for areas of magma-water interaction,constituting a baseline to compare with structural changes to be induced in future eruptions.

关键词： Hunga Tonga Hunga Ha'apai satellite gravity data 3D inversions volcano Tofua Island

Interfacial effects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： F. J. Sabina A.B.Movchan instituto de investigaciones en matematicas aplicadas yen sistemas Universidad Nacional Autónoma de México department of Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the effects of dispersion of Bloch-Floquet waves. A particular attention is given to structures containing interfaces between dissimilar media and localization of the electrical fields near such interfaces.

关键词： Piezoelectric periodic composites Interfaces Dispersion of Bloch-Floquet waves

Almost sure, L1-and L2-growth behavior of supercritical multi-type continuous state and continuous time branching processes with immigration

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Science China Mathematics 2020年第10期63卷 2089-2116页

作者： Mátyás Barczy Sandra Palau Gyula Pap MTA-SZTE Analysis and Stochastics Research Group Bolyai InstituteUniversity of SzegedSzeged H-6720Hungary department of Statistics and Probability Instituto de Investigaciones en Matemáticas Aplicadas y en SistemasUniversidad Nacional Autònoma de MéxicoCiudad de México 04510México Bolyai Institute University of SzegedSzeged H-6720Hungary

Under a first order moment condition on the immigration mechanism,we show that an appropriately scaled supercritical and irreducible multi-type continuous state and continuous time branching process with immigration(CBI process)converges almost *** an x log(x)moment condition on the branching mechanism does not hold,then the limit is *** this x log(x)moment condition holds,then we prove L1 convergence as *** projection of the limit on any left non-Perron eigenvector of the branching mean matrix is ***,in addition,a suitable extra power moment condition on the branching mechanism holds,then we provide the correct scaling for the projection of a CBI process on certain left non-Perron eigenvectors of the branching mean matrix in order to have almost sure and L1 ***,under a second order moment condition on the branching and immigration mechanisms,we prove L2 convergence of an appropriately scaled process and the above-mentioned projections as well.A representation of the limits is also provided under the same moment conditions.

关键词： multi-type continuous state and continuous time branching processes with immigration almost sure L1-and L2-growth behaviour

Redefinition of the Terminus of the Middle America Trench

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International Journal of Geosciences 2013年第4期4卷 766-776页

作者： Román Alvarez instituto de investigaciones en matemáticas aplicadas y en sistemas Universidad Nacional Autónoma de México Ciudad Universitaria México DF México

The terminus of the Middle America Trench has been traditionally represented as an arc, concave towards the continent. Tres Marías Islands are located at the terminus of the Middle America Trench in western Mexico, and their location is not only intriguing but also a key to the re-construction of the position of Baja California peninsula before separation from the North America plate. Previous re-constructions suggested various places around the location of Tres Marías Islands for the position of the tip of the peninsula, and several converge to a position that invades the area occupied by the islands, offering no explanation for the overlap. Before peninsular separation from North America, the Guadalupe trench followed a smooth curve;recreating the position of this paleo-trench yields a baseline for fixing the position of the peninsula, as well as the original position of the Tres Marías Islands fragment. A new tectonic view of the structure of the Middle America Trench terminus is proposed, replacing the traditional arc representation with a series of en echelon blocks, the northernmost terminates at the Tres Marías Escarpment. The long sides of the blocks correspond to previously identified geological faults in the Bahía de Banderas region, while their offshore continuation is supported by topographic observations. As a test of this model I show the corresponding re-construction of the position of Baja California prior to separation from the North America plate and the positional evolution of the peninsula and the Tres Marías fragment from Chron 4n.2 (7.90 Ma) to Chron 3n.4 (5.12 Ma).

关键词： Middle America Trench Tres Marías Islands Guadalupe Trench MAT Terminus Banderas Fault

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Chinese Annals of Mathematics,Series B 2009年第5期30卷 505-512页

作者： Angel CASTRO Diego CóRDOBA instituto de Ciencias matemticas CSIC-UAM-UC3M-UCMConsejo Superior de Investigaciones Científicas

The authors construct self-similar solutions for an N-dimensional transport equation,where the velocity is given by the Riezs *** solutions imply nonuniqueness of weak *** addition,self-similar solution for a one-dime... 详细信息

关键词： Hilbert transform Riesz transform Transport equations Self-similar solutions

Evidence of associative blocking during foraging in the social wasp Vespula germanica

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Insect Science 2021年第4期28卷 1103-1108页

作者： Sabrina Moreyra Paola D'Adamo Mariana Lozada Laboratorio Ecotono Instituto de Investigaciones en Biodiversidad y Medio Ambiente(INIBIOMA)-CONICET-Universidad Nacional del Comahue(CRUB)BarilocheArgentina

While foraging,Vespula germanica usually return to abundant food *** this relocation behavior,these wasps learn to identify contextual cues associated with food *** analyzed associative blocking in this species,that is,how an association with a conditioned stimulus(CS1)blocks subsequent learning when a novel stimulus(CS2)is added on a second foraging *** groups of wasps(A,B,and C;total 74 individual wasps)were observed while collecting meat during one or two consecutive *** group A,an environmental cue(CS1)was paired with food placed at a specific site,and on the second visit,a second cue(CS2)was added while food remained in the same *** a subsequent testing phase,CS1 was removed and the food source displaced *** then recorded the number of hovers performed over the empty dish(previously baited).Group A wasps appeared to ignore the addition of CS2 on their second visit because they performed fewer hovers over the learned *** group A,the duration of the decision-making process to finally fly toward the baited dish was shorter than when CS1 and CS2 were presented together on their first visit(group B).This is the first study to demonstrate the occurrence of associative blocking in vespids,confirming that a prior foraging experience influences subsequent food relocation in *** findings reveal that first learning episodes block further associations with novel contextual cues,contributing to understanding of complex cognitive processes involved in ***´s foraging behavior.

关键词： associative blocking foraging behavior learning prior experience social wasps