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Isotopic Variations of Oxygen (δ^(18)O) in Benthic Foraminifera under Antiestuarine Conditions in the Colorado River delta

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Open Journal of Geology 2018年第2期8卷 104-123页

作者： miguel A.Santa Rosa-del Río Ismael Yarbuh Rigoberto Guardado-France Ronald m.Spelz Raúl Herrera-gutiérrez Karla mejia-Pina miguel Agustín Tellez-Duarte Luis Antonio Cupul-magana Universidad Autónoma de Baja California Facultad de Ciencias MarinasArea de GeologíaEnsenadaMéxico

Benthic foraminifera are excellent environmental indicators;CaCO3 test records the isotopic concentration of their surroundings and can be used to analyze environmental changes that occur during a certain time period. Stable isotopes, particularly those of oxygen (δ18O), are useful for interpreting ancient environments, given that they are used as “proxy” environmental variables (temperature and salinity). In this study, we provide ranges of isotopic variation in benthic foraminifera communities from the Colorado River delta. Four sampling campaigns were conducted in one year (2009-2010) in the adjacent subtidal zone of Baja California. Four transects with a total of sixteen sample station were drawn perpendicular to the coastline. Here, we recorded the following in situ: sand-type, salinity, and temperature. In the laboratory, 300 individuals per sample were separated, and sub-samples were taken for isotopic analysis. Data was processed using the software’s R 2.12.2, PAST 1.81 and Arc map 9.3. Forty species were identified in the dead assemblages (Thanatocoenosis), whereas thirteen species were found in the living assemblages (Biocoenosis). The most abundant species in both communities belong to the genera Ammonia and Cribroelphidium. In the living assemblages, isotopic variation −2.15% to 5.94% within a temperature interval of 11°C, indicated antiestuarine conditions. In the dead assemblages, isotopic composition −3.04 to −0.74 served as a sign of estuarine conditions prior to damming.

关键词： Stable Isotopes Living Assemblages Dead Assemblages Upper Gulf of California

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On the electrophysiology of the atrial fast conduction system:an uncertain quantification study

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Acta mechanica Sinica 2021年第2期37卷 264-278页

作者： Giulio del Corso Roberto Verzicco Francesco Viola GSSI(Gran Sasso Science Institute) L'AquilaItaly University of Roma Tor Vergata RomeItaly POF Group University of TwenteEnschedeThe Netherlands

Cardiac modeling entails the epistemic uncertainty of the input parameters,such as bundles and chambers geometry,electrical conductivities and cell parameters,thus calling for an uncertainty quantification(UQ)*** the cardiac activation and the subsequent muscular contraction is provided by a complex electrophysiology system made of interconnected conductive media,we focus here on the fast conductivity structures of the atria(internodal pathways)with the aim of identifying which of the uncertain inputs mostly influence the propagation of the depolarization ***,the distributions of the input parameters are calibrated using data available from the literature taking into account gender *** output quantities of interest(Qols)of medical relevance are defined and a set of metamodels(one for each Qol)is then trained according to a polynomial chaos expansion(PCE)in order to run a global sensitivity analysis with non-linear variance-based SoboF indices with confidence intervals evaluated through the bootstrap *** most sensitive parameters on each Qol are then identified for both genders showing the same order of importance of the model inputs on the electrical ***,the probability distributions of the Qols are obtained through a forward sensitivity analysis using the same trained *** results that several input parameters-including the position of the internodal pathways and the electrical impulse applied at the sinoatrial node一have a little influence on the Qols ***-versa the electrical activation of the atrial fast conduction system is sensitive on the bundles geometry and electrical conductivities that need to be carefully measured or calibrated in order for the electrophysiology model to be accurate and predictive.

关键词： Uncertainty quantification Global sensitivity analysis Forward analysis Atrial modelling Electrophysiology monodomain model

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Plant peroxisomes at the crossroad of NO and H2O2 metabolism

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Journal of Integrative Plant Biology 2019年第7期61卷 803-816页

作者： Francisco J.Corpas Luis A.del Río José m.Palma Group of Antioxidants Free Radicals and Nitric Oxide in Biotechnology Food and Agriculture Department of Biochemistry Cell and Molecular Biology of Plants Estación Experimental del Zaidín CSIC

Plant peroxisomes are subcellular compartments involved in many biochemical pathways during the life cycle of a plant but also in the mechanism of response against adverse environmental *** organelles have an active nitro-oxidative metabolism under physiological conditions but this could be exacerbated under stress ***,peroxisomes have the capacity to proliferateand also undergo biochemical adaptations depending on the surrounding cellular *** important characteristic of peroxisomes is that they have a dynamic metabolism of reactive nitrogen and oxygen species(RNS and ROS)which generates two key molecules,nitric oxide(NO)and hydrogen peroxide(H2O2).These molecules can exert signaling functions by means of post-translational modifications that affect the functionality of target molecules like proteins,peptides or fatty *** review provides an overview of the endogenous metabolism of ROS and RNS in peroxisomes with special emphasis on polyamine and uric acid metabolism as well as the possibility that these organelles could be a source of signal molecules involved in the functional interconnection with other subcellular compartments.

关键词： Plant peroxisomes NO H2O2 metabolism

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Plant Growth-Promoting Traits in Rhizobacteria of Heavy metal-Resistant Plants and Their Effects on Brassica nigra Seed Germination

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Pedosphere 2017年第3期27卷 511-526页

作者： Brenda ROmN-PONCE Diana miryel REZA-VZQUEZ Sonia gutirrez-PAREDES maría de Jesús DE HARO-CRUZ Jessica mALDONADO-HERNNDEZ Yanely BAHENA-OSORIO Paulina ESTRADA-DE LOS SANTOS En Tao WANG maría Soledad VSQUEZ-mURRIETA Instituto Politécnico Nacional Escuela Nacional de Ciencias Biológicas Prolongación Carpio y Plan de Ayala s/n Col.Santo Tomás Del.Miguel Hidalgo Ciudad de México

Phytoremediation is an emerging technology that uses plants and their associated microbes to clean up pollutants from the soil, water, and air. In order to select the plant growth-promoting rhizobacteria （PGPR） for phytoremediation of heavy metal contamination, 60 bacterial strains were isolated from the rhizosphere of two endemic plants, Prosopis laevigata and Spharealcea angustifolia, in a heavy metal-contaminated zone in mexico. These rhizobacterial strains were characterized for the growth at different pH and salinity, extracellular enzyme production, solubilization of phosphate, heavy metal resistance, and plant growth-promoting （PGP） traits, including production of siderophores and indol-3-acetic acid （IAA）. Overall, the obtained rhizobacteria presented multiple PGP traits. These rhizoba^teria were also resistant to high levels of heavy metals （including As as a metalloid）（up to 480 mmol L-1 As（V）, 24 mmol L-1 Pb（II）, 21 mmol L-1 Cu（II）, and 4.5 mmol L-1 Zn（II））. Seven rhizobacterial strains with the best PGP traits were identified as members of Alcaligenes, Bacillus, Curtobacterium, and microbacterium, and were selected for further bioassay. The inoculation of Brassica nigra seeds with microbacteriurn sp. CE3R2, microbacterium sp. NE1R5, Curtobacterium sp. Nm1R1, and microbacterium sp. Nm3E9 facilitated the root development; they significantly improved the B. nigra seed germination and root growth in the presence of heavy metals such as 2.2 mmol L-1 Zn（II）. The rhizobacterial strains isolated in the present study had the potential to be used as efficient bioinoculants in phytorremediation of soils contaminated with multiple heavy metals.

关键词： bioinoculants endemic plants mine railings pH phytoremediation salinity

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Effect of Nitriding Current Density on the Surface Properties and Crystallite Size of Pulsed Plasma-Nitrided AISI 316L

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Journal of materials Science and Chemical Engineering 2015年第1期3卷 45-51页

作者： J. C. Díaz-Guillén E. E. Granda-gutiérrez G. Vargas-gutiérrez m. R. Díaz-Guillén J. A. Aguilar-martínez L. álvarez-Contreras Corporación mexicana de Investigación en materiales S.A. de C.V.-Cátedras-CONACyT Saltillo México Centro de Investigación y Estudios Avanzados del IPN Saltillo México GmyPQ Instituto de Investigaciones Eléctricas Cuernavaca México Universidad Autónoma de Nuevo León FIME-CIIIA Apodaca México Centro de Investigación en materiales Avanzados S.C. Chihuahua México

In this work, plasma-nitrided AISI 316L stainless steel samples were performed by ion nitriding process under pulsed direct current (DC) discharge at different current densities (1 to 2.5 mA/ cm2). The effect of nitriding current density on the size of crystalline coherently diffracting domains (crystallite size) and strain grade was investigated using X-ray diffraction (XRD) coupled with Williamson-Hall method. Additionally, hardness and wear resistance of the nitriding layer were characterized using a Vickers indenter and pin-on-disk technique respectively. Results showed a decrease in crystallite size from 99 nm for untreated samples to 1.4 nm for samples nitrided at 2.5 mA/cm2 promoted both: an increase in hardness from 226 HV25g to 1245 HV25g, and a considerably decrease in volume loss by wear effect.

关键词： Plasma Nitriding Strain Crystallite Size Hardness Wear Stainless

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Agronomic Use of Slurry from Anaerobic Digestion of Agroindustrial Residues: Effects on Crop and Soil

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Journal of Sustainable Bioenergy Systems 2014年第1期4卷 87-96页

作者： Amabelia del Pino Omar Casanova mónica Barbazán Victoria mancassola Laura Arló Liliana Borzacconi mauricio Passeggi Departamento de Ingeniería de Reactores Facultad de Ingeniería Universidad de la República Montevideo Uruguay Departamento de Suelos y Aguas Facultad de Agronomía Universidad de la República Montevideo Uruguay

In a greenhouse experiment we evaluated the application of slurry generated by a biogas reactor of agroindustrial residues. The objectives of this study were to determine the response to slurry application on dry matter production and nutrients absorption of Setaria italica (setaria), and to evaluate the effect of the slurry on soil properties. Two soils, of different texture, were mixed either with slurry or with diammonium phofsphate (DAP) at 0, 80, and160 kgN ha-1 equivalent rates. The setaria was harvested 68 days after planting, and separated into leaves plus stems, ears, and roots. Total biomass and content of N, P, K, Ca, mg, Cu, Fe, mn, and Zn were determined in each fraction. In the soil we determined pH, electric conductivity (EC), organic C, available P, mineral N, and exchangeable cations. Although the biomass produced and the amounts of nutrients absorbed were different in the two soils, in both of them setaria responded to the slurry application. The amounts of N absorbed from slurry and DAP were similar, indicating that the N from the slurry was readily available. The slurry application also increased the absorption of other macro and micro nutrients (P, Ca, mg, and Zn). No significant changes in soil exchangeable cations, pH, and EC were observed at setaria harvest. In the silty soil the crop almost depleted the mineral N in all treatments, but in the sandy soil large amounts were left, especially in the treatments with slurry. This fact highlights the importance of a careful dosage of this soil amendment, to avoid the excess of mineral N, which is potential pollutant for the environment. It can be concluded that the use of slurry from the reactor had a positive effect on the nutrients availability, without negative effects on soil properties.

关键词： Biosolids Biogas Slurry Setaria Italica Uruguay

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Flow Behavior of Clay-Silt to Sand-Silt Water-Rich Suspensions at Low to High Shear Rates: Implications for Slurries, Transitional Flows, and Submarine Debris-Flows

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2395-2404页

作者： Pierdomenico del GAUDIO Guido VENTURA Istituto Nazionale di Geofisica e Vulcanologia Via di Vigna Murata 60500143 RomeItaly Istituto per l'Ambiente marino Costiero Consiglio Nazionale delle RicercheNaplesItaly

Water-rich clay to sand suspensions show a shear rate dependent flow behavior and knowledge of the appropriate rheological model is relevant for sedimentological, industrial and hydraulic studies. We present experimental rheological measurements of water-rich(40 to 60 wt%) clay to silt(population A) and silt to sand(population B) suspensions mixed in different proportions. The data evidence a shear rate dependent shear thinning-shear thickening transition. At lower shear rates, the suspensions organize in chains of particles, whereas at higher shear rates, these chains disrupt so increasing the viscosity. The viscosity, consistency and yield stress decrease as the A+B fraction decreases as the content of B particles increases. This behavior reflects the competing effects of the lubrication and frictional processes as a function of particle size and water content. Transitional flows form by the incorporation of small amounts of the finer fraction while ‘oceanic floods’ form at the estuary of rivers and the submarine debris-flows increase their velocity by incorporating water. The critical Reynolds number of the studied suspensions is ～2000±100 suggesting that the grainsize plays a major role in the laminar to turbulent transition. Our results have implications for the modeling of sediment flows and the hazard related to floods.

关键词： rheology water-sediment suspensions slurry sludge transitional flows and mud flows volcanogenic sediment-water flows oceanic floods

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A Theoretically Grounded Question Answering Data Set for Evaluating machine Common Sense

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Data Intelligence 2024年第1期6卷 1-28页

作者： Henrique Santos Ke Shen Alice m.mulvehill mayank Kejriwal Deborah L.mcGuinness Rensselaer Polytechnic Institute Troy NY Information Sciences Institute Marina del Rey CA

Achieving machine common sense has been a longstanding problem within Artificial *** far,benchmark data sets that are grounded in a theory of common sense and can be used to conduct rigorous,semantic evaluations of common sense reasoning(CSR)systems have been *** expectation of the AI community is that neuro-symbolic reasoners can help bridge this gap towards more dependable systems with common *** propose a novel benchmark,called Theoretically Grounded common sense Reasoning(TG-CSR),modeled as a set of question answering instances,with each instance grounded in a semantic category of common sense,such as space,time,and *** benchmark is few-shot i.e.,only a few training and validation examples are provided in the public release to avoid the possibility of *** from recent evaluations suggest that TG-CSR is challenging even for state-of-the-art statistical *** to its semantic rigor,this benchmark can be used to evaluate the common sense reasoning capabilities of neuro-symbolic systems.

关键词： reasoning Intelligence instance

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Can VmD improve the estimate of the muon g-2?

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Chinese Physics C 2010年第6期34卷 698-704页

作者： m.Benayoun L.del Buono B.P.David O.Leitner LPNHE des Universits Paris VI et VII

We show that a VmD based theoretical input allows for a significantly improved accuracy for the hadronic vacuum polarization of the photon which contributes to the theoretical estimate of the muon g-2. We also show that the only experimental piece of information in the τ decay which cannot be accounted for within this VmD framework is the accepted value for Br（τ→ππvτ）, while the T spectum lineshape is in agreement with expectations from e^＋e^- annihilations.

关键词： VmD isospin symmetry breaking g-2

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Ready to migrate?Reading cellular signs of migration in an epithelial to mesenchymal transition model

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BIOCELL 2022年第11期46卷 2353-2356页

作者： TAmARA FERNÁNDEZ-CALERO IGNACIO LÓPEZ mARCOS DAVYT CORA CHALAR RICARDO EHRLICH mÓnica mARÍN Biochemistry-molecular Biology Faculty of ScienceUniversidad de la RepúblicaMontevideo11400Uruguay Bioinformatics Unit Institut Pasteur de MontevideoMontevideo11400Uruguay Departamento de Ciencias Exactas y Naturales Universidad Católica del UruguayMontevideo11600Uruguay Institut Pasteur de montevideo Montevideo11400Uruguay

The epithelial to mesenchymal transition(EmT)is a cellular program that drives de-differentiation of cells in both physiological and pathological *** of the characteristics of cells describing an EmT is the(re)acquisition of a motility capacity that allows them to migrate through the original tissue as well as to other sites in the *** molecular mechanisms that control the EmT are rapidly emerging and here we add to the idea that the adaptation required for cells to commit to the EmT includes adjustments of the translation machinery and metabolic pathways to cope with a high demand of extracellular components.

关键词： EmT migration Translation machinery metabolism

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