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Processes involving soil CO_(2)dynamic in a sector of Chaco-Pampean plain,Argentina:An isotope geochemical approach

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Acta Geochimica 2024年第5期43卷 947-958页

作者： Sanci Romina Panarello héctor Instituto de Geociencias Básicas Aplicadas y Ambientales de Buenos Aires(IGEBA)Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCABAIntendente Güiraldes 2160Pabellón IIPiso 1C1428EGA Ciudad UniversitariaArgentina Instituto de Geocronología y Geología Isotópica(INGEIS) Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCABAIntendente Güiraldes 2160Pabellón INGEISC1428EGA Ciudad UniversitariaArgentina

The magnitude and spatial variability of CO_(2)surface emissions and processes involving CO_(2)released to the atmosphere from the soils are relevant issues in the context of climate *** work evaluated CO_(2)fluxes and^(13)C/^(12)C ratio of vegetation,organic matter,and soil gases from no disturbed soils of Chaco Pampean Plain(Argentina)with different soil properties and environmental conditions(PL and PA units).Soil organic decomposition from individual layers was accompanied byδ^(13)C of total organic carbon(δ^(13)C-TOC)values more enriched to depth.δ^(13)C-TOC values in the upper soil profile~ca.0–15 cm were like the plant community of this area(~−33 to−29‰)whileδ^(13)CTOC varied stronger bellow horizon A,till~−24‰.Bothδ^(13)C-TOC and soilδ^(13)C-CO_(2)were similar(~−24 to 26‰)at deeper horizons(~50–60 cm).Toward the superficial layers,δ^(13)C-TOC andδ^(13)C-CO_(2)showed more differences(till~4‰),due influence of the diffusion *** A layer(~0–20 cm)from both PL and PA units contained the most enrichedδ^(13)C-CO_(2)values(~−15–17‰)because atmospheric CO_(2)permeated the soil air.A simple two-component mixing model between sources(atmosphericδ^(13)C-CO_(2)and soil CO_(2))confirmed that ***,CO_(2)fluxes reflected the biodegradation of C3 plants(source),diffusive transport,and CO_(2)exchange(atmosphere/soil).Soil moisture content appeared as a determining factor in the diffusion process and the magnitude of CO_(2)surface emissions(12–60 g·m^(−2)·d^(−1)).That condition was confirmed by CO_(2)diffusion coefficients estimated by air-filled porosity parameters and soil radon gradient model.

关键词： Soil CO_(2) Carbon isotopes Isotope fractionation Radon gases

Mitochondrial dysfunction as a target in spinal cord injury:intimate correlation between pathological processes and therapeutic approaches

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Neural Regeneration Research 2023年第10期18卷 2161-2166页

作者： Julieta Schmidt héctor Ramiro Quintá Universidad de Buenos Aires CABAArgentina Laboratorio de Medicina Experimental“Dr.J.Toblli” Hospital AlemánCABAArgentina Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET CABAArgentina Rehabilitation Medicine Department University of MinnesotaTwin CitiesMINUSA

Traumatic spinal cord injuries interrupt the connection of all axonal projections with their neuronal targets below and above the lesion site. This interruption results in either temporary or permanent alterations in the locomotor, sensory, and autonomic functions. Damage in the spinal tissue prevents the re-growth of severed axons across the lesion and their reconnection with neuronal targets. Therefore, the absence of spontaneous repair leads to sustained impairment in voluntary control of movement below the injury. For decades, axonal regeneration and reconnection have been considered the opitome of spinal cord injury repair with the goal being the repair of the damaged long motor and sensory tracts in a complex process that involves:(1) resealing injured axons;(2) reconstructing the cytoskeletal structure inside axons;(3) re-establishing healthy growth cones;and(4) assembling axonal cargos. These biological processes require an efficient production of adenosine triphosphate, which is affected by mitochondrial dysfunction after spinal cord injury. From a pathological standpoint, during the secondary stage of spinal cord injury, mitochondrial homeostasis is disrupted, mainly in the distal segments of severed axons. This result in a reduction of adenosine triphosphate levels and subsequent inactivation of adenosine triphosphate-dependent ion pumps required for the regulation of ion concentrations and reuptake of neurotransmitters, such as glutamate. The consequences are calcium overload, reactive oxygen species formation, and excitotoxicity. These events are intimately related to the activation of necrotic and apoptotic cell death programs, and further exacerbate the secondary stage of the injury, being a hallmark of spinal cord injury. This is why restoring mitochondrial function during the early stage of secondary injury could represent a potentially effective therapeutic intervention to overcome the motor and sensory failure produced by spinal cord injury. This

关键词： adenosine triphosphate axonal regeneration creatine mitochondria dysfunction mitochondria spinal cord injury

Application of high silica zeolite ZSM-5 in a hybrid treatment process based on sequential adsorption and ozonation for VOCs elimination

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Journal of Environmental Sciences 2016年第3期28卷 59-68页

作者： hicham Zaitan Marie hélène Manero héctor Valdés Laboratoire de Chirmie de la Matiere Condensee(LCMC) Faculte des Sciences et TechniquesUniversite Sidi Mohamed Ben AbdellahB.P.2202FesMaroc Universite de Toulouse INPTUPSLaboratoire de Genie Chimique4Allee Emile MonsoF-31030 ToulouseFrance CNRS Laboratoire de Genie ChimiqueF-31030 ToulouseFrance Laboratorio de Tecnologias Limpias(F.Ingenieria) Universidad Catolica de la Santisima ConcepcionAlonso de Ribera 2850ConcepcionChile

In this study,a hydrophobic synthetic zeolite,namely ZSM-5 is chosen as an adsorbent/catalyst for toluene *** results showed that toluene adsorption onto ZSM-5 was favourable,following a Langmuir adsorption isotherm ***-5 zeolite was regenerated using gaseous ozone at low *** toluene was oxidised,releasing mainly CO_2 and h_*** of oxidation by-products such as acetic acid and acetaldehyde were formed and remained adsorbed after the oxidativate regeneration with *** four successive cycles of adsorption/ozonation,the adsorption efficiency was not affected（92%-99%）.These results showed that volatile organic compound（VOC）removal by adsorption onto ZSM-5 zeolite followed by ozone regeneration could be used as a promising hybrid process for the control of VOC emissions in terms of efficiency.

关键词： Adsorption Ozone Toluene VOCs Zeolite

EXTRACTING BEhAVIOURAL MODELS FROM 2010FIFA WORLD CUP

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Journal of Systems Science & Complexity 2013年第1期26卷 43-61页

作者： MENNDEZ héctor BELLO-ORGAZ Gema CAMAChO David Department of Computer Science Universidad Autnoma de Madrid

The FIFA World Cup^(TM) is the most profitable worldwide *** FIFA publishes global statistics of this competition which provide global data about the players and teams during the *** work is focused on the extraction of behavioural patterns for both,players and teams strategies,through the automated analysis of this *** knowledge and models extracted in this work could be applied to soccer leagues or even it could be oriented to sport ***,the main contribution is related to the study on several automatic knowledge extraction techniques,such as clustering methods,and how these techniques can be used to obtain useful behavioural models from a global statistics *** information provided by the clustering algorithms shows similar properties which have been combined to define the models,making the human interpretation of these statistics ***,the most successful teams strategies have been analysed and compared.

关键词： Behavioural patterns clustering FIFA World Cup football soccer web mining.

Liquid-liquid interfacial tension of equilibrated mixtures of ionic liquids and hydrocarbons

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Science China Chemistry 2012年第8期55卷 1519-1524页

作者： RODRíGUEZ héctor ARCE Alberto SOTO Ana Department of Chemical Engineering University of Santiago de Compostela E-15782 Santiago de Compostela Spain

Ionic liquids are possible alternative solvents for the separation of aromatic and aliphatic hydrocarbons by liquid-liquid extrac- tion. Interfacial tension is an important property to consider in the design of liquid-liquid extraction processes. In this work, the liquid-liquid interfacial tension and the mutual solubility at 25 ℃ have been measured for a series of biphasic, equilibrated mixtures of an ionic liquid and a hydrocarbon. In particular, the ionic liquids 1-alkyl-3-methylimidazolium bis（trifluorome- thanesulfonyl）imide （with the alkyl substituent being ethyl, hexyl or decyl）, 1-ethyl-3-methylimidazolium ethylsulfate, and 1-ethyl-3-methylimidazolium methanesulfonate have been selected, as well as the hydrocarbons benzene, hexane, ethylben- zene, and octane. The selected sets of ionic liquids and hydrocarbons allow the analysis of the influence of a series of effects on the interfacial tension. For example, the interfacial tension decreases with an increase in the length of the alkyl substituent chain of the cation or with an increase of the degree of charge delocalisation in the anion of the ionic liquid. Also, the interfa- cial tension with the aromatic hydrocarbons is markedly lower than that with the aliphatic hydrocarbons. A smaller effect is caused by variation of the size of the hydrocarbon. Some of the observed trends can be explained from the mutual solubility of the hydrocarbon and the ionic liquid.

关键词： ionic liquid aromatic hydrocarbon aliphatic hydrocarbon interfacial tension liquid-liquid equilibrium

Regulating lithium nucleation and growth by zinc modified current collectors

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Nano Research 2020年第1期13卷 45-51页

作者： Na Zhang Seung-ho Yu héctor D.Abruna Baker Laboratory Department of Chemistry and Chemical BiologyCornell UniversityIthacaNew York14853USA Department of Chemical and Biological Engineering Korea University145 Anam-roSeongbuk-guSeoul02841Republic of Korea

Lithium metal is commonly regarded as the“holy Grail”anode material for high energy density rechargeable ***,the uncontrollable growth of Li dendrites has posed safety concerns and thus greatly hindered its large-scale *** we have modified the surface of a commercial anode current collector,Cu foil,with a thin layer of Zn by a facile electroplating method,in order to regulate the Li nucleation and the following growth *** of the formation of a solid solution buffer layer and Li-Zn alloy phases,the Li nucleation overpotential was dramatically reduced,realizing a uniform Li nucleation and a smooth Li plating *** a result,significantly improved long-term cycling performance with a high Coulombic efficiency was achieved by the lithiophilic Zn coated Cu foil as a current *** cells of Li-LiFePO4 and Li-S using the Li deposited on the Zn modified Cu as the anode,showed increased capacity with low voltage hysteresis and greatly enhanced cycling stability,ascribed to the uniform Li deposition and formation of a stable SEI *** work demonstrates the feasibility of employing lithiophilic modified Cu foils as Li metal current collectors for practical applications.

关键词： lithium metal anode lithium dendrite current collector zinc layer

Bedrock outcropping in the accumulation zone of the largest glacier in Mexico(Glaciar Norte of Citlaltépetl),as evidence of a possible accelerated extinction

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Journal of Mountain Science 2023年第2期20卷 338-354页

作者： SOTO Víctor Colegio de Geografía Facultad de EconomíaUniversidad VeracruzanaAv.Xalapa s/nObrero Campesina91020XalapaVer.México

The highest volcano in Mexico,at the same time the third largest mountain in North America(Citlaltépetl,5610 m a.s.l.),is home to the largest glacier in the *** of the extinction of the Popocatépetl glacier(5500 m a.s.l.)caused by eruptive activity,and the almost disappearance of the Iztaccíhuatl glaciers(5220 m a.s.l.)due to the lower elevation of the mountain,the Glaciar Norte of Citlatépetl has been the only glacier that has shown a certain degree of stability as a response to the altitude in which it is ***,as occurs in almost all glaciers on the planet,the retreat of its glacier terminus has been ***,during the last years the thickness of its upper part began to decrease rapidly until its bedrock was exposed for the first time in *** to its ecosystem importance and because it is the main glacier in Mexico,as well as the only one in the world located at latitude 19°N,in this work its current dimensions are updated,as well as the local climatology that governs the current state of the glacier is pointed *** study was based on the analysis of high-resolution Sentinel-2 optical images,as well as through Sentinel-1 SAR images,with the support of climatological information from the study ***,the outcropping of the bedrock in the accumulation zone and the consequent horizontal retreat of the upper part of the glacier are documented;at the same time,the decrease in the thickness of the ice along it is *** rocky outcrop in the accumulation zone suggests that the flow dynamics of the ice towards the ablation zone will be considerably less,accelerating the retreat of the glacier ***,the ascent of the glacial front to 5102 m *** the modelled altitude of the equilibrium line to 5276 m *** reported as a warning signal in terms of snow catchment and mass balance;likewise,the decrease of 23%of its surface is also indicated regarding the surface reduction monitoring that has been done

关键词： Bedrock outcrop Citlaltépetl glacier Glacial accumulation zone Glacier retreat Glacial thickness

The ecological scale mediates whether trees experience drought legacies in radial growth

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Forest Ecosystems 2023年第3期10卷 298-306页

作者： héctor hernández-Alonso Jaime Madrigal-González Fernando Silla Area of Ecology Faculty of BiologyUniversidad de SalamancaE-37007SalamancaSpain iuFOR-EiFAB Campus de SoriaUniversidad de ValladolidE-42004SoriaSpain

The impact of lag effects produced by disturbances on primary production has been a major concern among ecologists during the last *** and extreme climatic events are imposing drastic reductions in radial growth of trees as evidenced in tree-rings series Dendrochronological samples are obtained at tree level but analyzed at an aggregated scale(i.e.,mean chronologies),although aggregating tree-ring chronology on a regional scale may reduce the possibility of studying the variability of individual tree response to drought,by amplifying the average population ***,we conducted experimental research in which 370 trees of 5 species were analyzed to assess the potential statistical and scaling issues that may occur when using regressionbased methods to analyze ecosystem responses to *** legacy effects were quantified using individual and aggregated ***,lag effects were validated using confidence and prediction intervals to identify values falling outside the certainty of the climate-growth model Individual scale legacy effects contrasted with confidence intervals were commonly distributed across species but were scarce when compared with prediction *** analysis of aggregated scale legacies detected significant growth reductions when validated using prediction intervals;however,individual scale legacy lag effects were not *** finding directly contrasts the results obtained when using an aggregated *** results provide empirical evidence on how aggregating ecological data to infer processes that emerge from an individual scale can lead to distorted *** therefore encourage the use of individual based statistical and ecological procedures to analyze tree rings as a means of further understanding the ecosystem responses to disturbances.

关键词： Legacy effects Drought disturbances Tree growth Tree-ring width Dendrochronology Individual scale Mountainous forests

Getting started in mapping-by-sequencing

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Journal of Integrative Plant Biology 2015年第7期57卷 606-612页

作者： héctor Candela Rubén Casanova-Sáez José Luis Micol Instituto de Bioingeniería Universidad Miguel Hernández Department of Forest Genetics and Plant Physiology Umea Plant Science CenterSwedish University of Agricultural Sciences

Next-generation sequencing （NGS） technologies allow the cost-effective sequencing of whole genomes and have expanded the scope of genomics to novel applications, such as the genome-wide characterization of intraspecific polymorphisms and the rapid mapping and identification of point mutations. Next-generation sequencing platforms, such as the Illumina hiSeq2ooo platform, are now commercially available at affordable prices and routinely produce an enormous amount of sequence data, but their wide use is often hindered by a lack of knowledge on how to manipulateand process the information produced. In this review, we focus on the strategies that are available to geneticists who wish to incorporate these novel approaches into their research but who are not familiar with the necessary bioinformatic concepts and computational tools. In particular, we comprehensively summarize case studies where the use of NGS technologies has led to the identification of point mutations, a strategy that has been dubbed ＂mapping-by-sequencing＇, and review examples from plants and other model species such as Caenorhabditis elegans, Saccharomyces cerevisiae, and Drosophila mela- nogaster. As these technologies are becoming cheaper and more powerful, their use is also expanding to allow mutation identification in species with larger genomes, such as many crop plants.

关键词： Mapping-by-sequencing massively parallel sequencing mutation identification ShOREmapping whole-genome re-sequencing