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Journal of Earth Science 2024年

作者： FlORES Daniel Germán oca?A raúl.emmanuel.mel.án edgardo ORTEG Andrés ESPER AnGIllIERI María Yanina PITTAlUGA María Alejandra CIGEOBIO (COnICET-UnSJ) Av.José I.de la Roza y Meglioli Gabinete de Geología Ambiental InGEO Universidad nacional de San Juan Av.José I.de la Roza y Meglioli

The Monte Desert is characterized by a great diversity of landforms created with fluvial， alluvial which the vegetation patterns are related to. The present work has the following objectives: 1: determine whether topographical attributes， surface characteristics， soil properties and vegetation patterns vary between alluvial landforms， and 2: define whether morphometric， soil and surface properties influence vegetation patterns along alluvial landscape. Morphometric data were obtained by processing a 5 m digital elevation model. The coverage of rock fragments， fine sediments and mulch was quantified. Observations and descriptions of the soil profiles were restricted to the uppermost 50 cm. Vegetation properties were calculated using a Point Quadrat Method. The relationship between variables was evaluated through multivariate statistical analysis. The main results show the presence of 45 plant species distributed in 19 families， where shrubs are dominant. The wind effect， topographic wetness and dissection of the landscape are limiting factors of diversity. The coverage of superficial rock fragments influence vegetation coverage through the distribution and availability of rainwater. Furthermore， the different soil textures reveal that the silt content favors an increase in vegetation coverage. The presence of V horizon could condition the installation and development of vegetation in the early stages of growth.

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What is the prognosis of emphysematous pyelonephritis associated with extended-spectrum beta-lactamases producing microorganisms?

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Asian Journal of Urology 2022年第2期9卷 146-151页

作者： JoséIván Robles-Torres Marco Alberto ocaña-Munguía JoséGustavo Arrambide-Herrera Adrián Mauricio Martínez-Fernández Rodrigo Romero-Mata lauro Salvador Gómez-Guerra Urology Department Hospital Universitario"Dr.Jose´Eleuterio Gonza´lez"Universidad Auto´noma de Nuevo LeonMonterreyNuevo LeonMexico

Objective:To describe the microbiological characteristics in emphysematous pyelonephritis(EPn),demonstrate the frequency of extended-spectrum beta-lactamase(ESBl)microorganisms,and determine if these microorganisms are associated with the prognosis of patients with ***:We conducted a retrospective study in patients with a diagnosis of EPn in a tertiary care hospital of the northeast region of Mexico during the period from January 2011 to January *** variables were analyzed to determine association with the presence of ESBl-producing *** significance was set with pl of 63 patients were included;55(87.3%)of them were females,with a median age of 55(interquartile range:45-65)*** management was indicated in 38.1%;42.9%were treated with ureteral stent;12.7%with open or percutaneous drainage;15.8%with early nephrectomy;and 9.5%with delayed *** mortality was 13(20.6%)cases;23(36.5%)cases required admission to the intensive care *** most frequent microorganism isolated was Escherichia coli(n=34,53.9%).ESBl microorganisms were found in 31.7%of the *** significant association of ESBl was found with admission to the intensive care unit,or with increased ***:To our knowledge,this is the first study that evaluates ESBl microorganisms as a prognostic factor in *** factors associated with a poor prognosis in patients with EPn have been *** microbiological factors,specifically ESBl-producing bacteria,do not seem to influence in the prognosis of these patients.

关键词： Emphysematous pyelonephritis Extended spectrum betalactamase Mortality Intensive care unit admission

Training data selection for accuracy and transferability of interatomic potentials

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npj Computational Materials 2022年第1期8卷 1795-1803页

作者： David Montes de oca Zapiain Mitchell A.Wood nicholas lubbers Carlos ZP.ereyra Aidan P.Thompson Danny Perez Sandia national laboratories AlbuquerqueNM87185USA Computer Computationaland Statistical Sciences DivisionLos Alamos National LaboratoryLos AlamosNM87545USA Mechanical and Aerospace Engineering University of California DavisDavisCA95616USA Theoretical Division Los Alamos National LaboratoryLos AlamosNM87545USA

Advances in machine learning(Ml)have enabled the development of interatomic potentials that promise the accuracy of first principles methods and the low-cost,parallel efficiency of empirical ***,Ml-based potentials struggle to achieve transferability,i.e.,provide consistent accuracy across configurations that differ from those used during *** order to realize the promise of Ml-based potentials,systematic and scalable approaches to generate diverse training sets need to be *** work creates a diverse training set for tungsten in an automated manner using an entropy optimization ***,multiple polynomial and neural network potentials are trained on the entropy-optimized dataset.A corresponding set of potentials are trained on an expert-curated dataset for tungsten for *** models trained to the entropy-optimized data exhibited superior transferability compared to the expert-curated ***,the models trained to the expert-curated set exhibited a significant decrease in performance when evaluated on out-of-sample configurations.

关键词： entropy transfer configuration

High Temperature Oxidation of a Work Roll Grade High-Chromium White Cast Iron

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Journal of Iron and Steel Research(International) 2013年第10期20卷 122-129页

作者： J H ramírez-ramírez R Colás n F Garza-Montes-de-oca Faculty of Mechanical and Electrical Engineering Autonomous University of Nuevo Leon

High-chromium white cast iron is a common material for the manufacture of the work rolls used in the fin- ishing stands in hot strip mills. The high temperature oxidation behaviour of as-cast and heat-treated high-chromium white cast iron was studied by gravimetric means at 650 ℃ in atmospheres that included dry air and a mixture of dry air and water vapour. For both environmental and material conditions, the oxidation rate of the alloys was represen ted by parabolic trends and the oxidation phenomenon was more obvious when the samples were oxidised in water vapour. Water vapour also influenced the chemical composition of the oxides formed in the alloy and under this condi tion, the oxide scale formed on the alloy contained the oxides FeCr2O4 , （Fe,Cr）3O4 and （Fe,Cr）2 O3. In contrast, the alloys exposed to dry air conditions only experienced the formation of FeCr2O4 and （Fe,Cr）2O3. It was found that the presence of water vapour and the chromium content of the alloys increased the oxidation rate by a mechanism that involved chromium depletion of the oxide as a result of hydroxide formation. The differences observed in the oxi- dation behaviour of the alloy are discussed in terms of the composition of the oxidant atmosphere and the metallurgi cal condition of the specimens.

关键词： white cast iron oxidation water vapour work roll

Accelerating phase-field-based microstructure evolution predictions via surrogate models trained by machine learning methods

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npj Computational Materials 2021年第1期7卷 9-19页

作者： David Montes de oca Zapiain James A.Stewart Rémi Dingreville Center for Integrated nanotechnologies Sandia National LaboratoriesAlbuquerqueNM 87185USA Energetic Materials Dynamic and Reactive Science Sandia National LaboratoriesAlbuquerqueNM 87185USA

The phase-field method is a powerful and versatile computational approach for modeling the evolution of microstructures and associated properties for a wide variety of physical,chemical,and biological ***,existing high-fidelity phase-field models are inherently computa fonally expensive,requiring high-performance computing resources and sophisticated numefical integration schemes to achieve a useful degree of *** this paper,we present a computationally inexpensive,accurate,data-driven surmogate model that directly learns the microstructural evolution of targeted systems by combining phase-field and history-dependent machine-learning *** integrate a statisti cally representative,low-dimensianal description of the micrastructure,obtained direcdy from phase-field simulations,with either a time-series multivariate adaptive regression splines autoregressive al garithm or a lang short-term memory neural *** neural-network-trained surrogate model shows the bestperformance and accurately predicts the nanlinear microstructure evolutian of a two-phase mixture during spinodal decomposition in seconds,without the need for"on-the-fly"solutions of the phase-field equations of *** also show that the predictions from our machine learned surrogate model can be fed directly as an input into a classical high-fideli ty phase-field model in order to accelerate the high-fidelity phase field simulations by leaping in *** machine-learned phase-field framework opens a promising path forward to use accelerated phase field simulations for discovering,understanding,and predicting processing-microstructure-performance relationships.

关键词： phase versatile statist

Biorefinery of Rice Husk to Obtain Functionalized Bioactive Compounds

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Journal of Renewable Materials 2019年第4期7卷 313-324页

作者： M.lopretti n.lecot A.Rodriguez G.lluberas F.Orozco l.Bolaños G.Montes De oca H.Cerecetto J.Vega-Baudrit laboratorio de Técnicas nucleares Aplicadas a Bioquímica y Biotecnología Centro de Investigaciones Nucleares-Facultad de CienciasMataojo 2055Montevideo CP 11400Uruguay Área de radiofarmacia Centro de Investigaciones Nucleares-Facultad de CienciasMataojo 2055Montevideo CP 11400Uruguay Química Bioanalítica Instituto Polo Tecnológico de Pando-Facultad de QuímicaUdelaRBy Pass de Pando y Ruta 8Pando-Canelones CP 91000Uruguay laboratorio de nacional de nanotecnología-CenAT-COnARE Costa Rica 1174-1200San JoséCP 10109Costa Rica laboratorio de Polímeros POLIUNA-Escuela de Química Universidad NacionalHerediaSan JoséCP 86-3000Costa Rica

The biomass industrialization valorisation of grains and cereals is considered an opportunity for the countries where agro-industrial activity is one of its main economic activities,rendering new higher-value products with a concomitant solution to waste accumulation *** that end,in this work we describe and characterise bioactive compounds generation from rice husk by semisolid fermentation,obtained from 500 g of the material at room temperature and 60%humidity with mixed cultures of Phanerochaete chrysosporium and Gloeophyllum *** extract was evaluated in different situations:murine mammary tumour cells(4T1),normal cells(nIH 3T3)and in lactobacillus acidophilus,and Trichoderma *** results exhibited that the extract inhibited 4T1 cells at concentrations higher than 20μg/ml,but did not inhibit normal cells,and displayed germicide activity after 3 days *** propose that these functionalized compounds have a potential application in industry/agriculture/medicine obtained from rice husk waste.

关键词： Biorefinery rice husk bioactive compounds valorisation of biomass veratryl alcohol

Role of seed size, phenology, oogenesis and host distribution in the specificity and genetic structure of seed weevils (Curculio spp.) in mixed forests

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Integrative Zoology 2018年第3期13卷 267-279页

作者： Harold ARIAS-lEClAIRE raúl BOnAl Daniel GARCÍA-lÓPEZ Josep Maria ESPElTA CREAF Centre for Ecological Research and Forestry ApplicationsCerdanyola del Vallès08193Spain Exact and natural Sciences School State Distance University of Costa RicaUNEDMercedes de Montes de OcaSan JoséCosta Rica Forest Research Group INDEHESAUniversity of ExtremaduraPlasenciaSpain DITEG Research Group University of Castilla-La ManchaToledoSpain Zoology Department Autonomous University of BarcelonaCerdanyola del VallèsSpain

Synchrony between seed growth and oogenesis is suggested to largely shape trophic breadth of seed-feeding insects and ultimately to contribute to their co-existence by means of resource partitioning or in the time when infestation *** we investigated:(i)the role of seed phenology and sexual maturation of females in the host specificity of seed-feeding weevils(Curculio spp.)predating in hazel and oak mixed forests;and(ii)the consequences that trophic breadth and host distribution have in the genetic structure of the weevil *** analyses were used to establish unequivocally host specificity and to determine the population genetic *** identified 4 species with different specificity,namely Curculio nucum females matured earlier and infested a unique host(hazelnuts,Corylus avellana)while 3 species(Curculio venosus,Curculio glandium and Curculio elephas)predated upon the acorns of the 2 oaks(Quercus ilex and Quercus pubescens).The high specificity of *** coupled with a more discontinuous distribution of hazel trees resulted in a significant genetic structure among *** addition,the presence of an excess of local rare haplotypes indicated that *** populations went through genetic expansion after recent ***,these effects were not observed in the more generalist Curculio glandium predating upon ***,co-existence of weevil species in this multi-host-parasite system is influenced by both resource and time *** what extent the restriction in gene flow among *** populations may have negative consequences for their persistence in a time of increasing disturbances(*** in Mediterranean areas)deserves further research.

关键词： Corylus avellana Curculio spp. genetic structure Quercus spp. trophic breadth

Management of occult hepatitis B virus infection:An update for the clinician

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World Journal of Gastroenterology 2011年第12期17卷 1563-1568页

作者： Joséluis lledó Conrado Fernández María luisa Gutiérrez Sara ocaa Gastroenterology Unit Hospital Universitario Fundación AlcorcónAv Budapest-128922 AlcorcónMadridSpain laboratory Unit Hospital Universitario Fundación AlcorcónAv Budapest-128922 AlcorcónMadridSpain

Occult hepatitis B virus(HBV) infection(OBI) is defined by the presence of HBV DnA in the liver tissue of individuals who test negative for hepatitis B surface antigen(HBsAg).Patients who have recovered from acute hepatitis B can carry HBV genomes for a long time and show histological patterns of mild necro-inflammation,even fibrosis,years after the resolution of acute hepatitis,without showing any clinical or biochemical evidence of liver *** least in conditions of immunocompetence,OBI is inoffensive itself,but when other relevant causes of liver damage are present it might make the course of the liver disease *** risk of HBV transmission through transfusion is related to blood donations negative for HBsAg that have been collected during the pre-seroconversion period or during chronic *** of HBV nucleic acid amplification testing and multivalent anti-HBs antibodies in the HBsAg assays is recommended for detection of true and false OBI,*** is not known if prior hepatitis B immunization with an optimal anti-HBs response in cases of HBV transmission through organ transplantation can effectively modulate or abort the *** of anti-viral agents as prophylaxis in patients with serological evidence of past HBV infection prevents reactivation of OBI after transplantation in most *** of OBI has been observed in other conditions that cause immunosuppression,in which antiviral therapy could be delayed until the HBV DnA or HBsAg becomes *** might contribute to the progression of liver fibrosis and hepatocellular carcinoma development in patients with chronic liver disease.

关键词：秘密肝炎 B 管理输血机关移植病毒复活长期的肝疾病 Hepatocellular 癌

Adsorption of cobalt by using inorganic components of sediment samples from water bodies

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International Journal of Sediment Research 2021年第4期36卷 524-531页

作者： Rocío Montes de oca-Palma Marcos Solache-Ríos melania Jiménez-Reyes José Juan García-Sánchez Perla Tatiana Almazán-Sánchez Instituto nacional de Investigaciones nucleares Departamento de Química Tecnológico de Estudios Superiores de Jocotitlán Cátedras COnACyT-Instituto nacional de Investigaciones nucleares

The adsorption of cobalt ions was evaluated using sediment samples from water bodies to investigate the adsorption properties of sediment and the behavior of these natural materials in the presence of nuclear and industrial waste. The two sediments(S1 and S2) were treated to eliminate humic and fulvic acids and then they were characterized by several techniques. The minerals found in both the sediments(X-ray diffraction) were quartz and albite; plus, goethite and muscovite in S1, and kaolinite and montmorillonite in S2. Point of zero charge(PZC) of S1 and S2 was 6.00 and 5.22, respectively. The specific area of S1(63.3 m2/g) is higher than S2(1.5 m2/g). Adsorption kinetics data for S1 and S2 were best fitted to the pseudo second-order model. The removal efficiency of S1 for cobalt was 96% with an adsorption capacity(qe) of 0.93 mg/g, and for S2 was 45% with a qeof 0.40 mg/g. The experimental data of the adsorption isotherms were adjusted to langmuir and Freundlich models for S1 and S2, respectively. The thermodynamic parameters(enthalpy, entropy, and Gibb’s free energy) indicated that the adsorption processes were endothermic, spontaneous, and chemisorption mechanism. The results show that the adsorption capacities of the sediments depend on their composition. These water sediments have important adsorption properties for cobalt, and they can be used in the treatment of nuclear and industrial aqueous wastes.

关键词： Water-body sediment Cobalt ions Adsorption

Copper Oxide Inked with Dye Obtained from the lactarius Indigo Fungus for Energy Production

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Journal of Materials Science and Chemical Engineering 2022年第11期10卷 36-51页

作者： Abigail Bautista Castañeda Maria Guadalupe Montes De oca Dulce Yolotzin Medina Velazquez Jorge Iván Aldana González Pedro Adrian Martinez Montolla Joan Reyes Miranda Miguel Angel Barron Universidad Autónoma Metropolitana Departamento de Materiales Ciencias Básicas e Ingeniería Reynosa Tamaulipas México Instituto Politécnico nacional ESIQIE UPALM S/N Col. Mexico City México

The results obtained from the characterization of a copper deposit on indium doped tin oxide (ITO), inked with natural dye extracted from the lactarius indigo fungus, for use in Gratzel type solar cells are reported. An electrolyte composed of 0.1 M HnO3 and 0.5 M CuSO4 was used, this solution was prepared for copper deposits on the ITO. Cyclic voltammetry was performed at different scan rates to obtain the reduction zone for deposition between potentials of ?100 to ?500 mV. The dye was obtained from the indigo lactarius fungus from maceration, once the inked deposits were obtained, characterizations were performed, the initial test was to obtain the Ultraviolet-Visible (UV-visible) of the pure dye, and later the same test was performed on the inked oxide. Electrochemical Impedance Spectroscopy (EIS) was performed on the samples, as well as Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM), to characterize the material properties for its application.

关键词： Copper Oxide Ink Dye Energy Production Indigo Milk Mushroom