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Mantle derived crystal-poor rhyolitic ignimbrites:Eruptive mechanism from geochemical and geochronological data of the Piedra Parada caldera,Southern Argentina

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Geoscience Frontiers 2018年第5期9卷 1529-1553页

作者： Eugenio Aragon Antonio Castro juan diaz-alvarado Lucio Pinotti Fernando D'eramo Manuel Demartis Jorge Coniglio Irene Hernando Carmen Rodriguez Centro de Investigaciones Geológicas(UNLP-CONICET) 1 N^o 644(1900)La PlataBuenos AiresArgentina Departamento de Geología Universidad de Huelva21071 HuelvaSpain Departamento de Geología Universidad de AtacamaCopayapu 485CopiapóChile Departamento de Geología Universidad Nacional de Río Cuarto(UNRC-CONICET)Ruta 36 km 601Río CuartoCórdobaArgentina

Trace elements, isotopic modeling and U-Th-Pb SHRIMP zircon age constraints are used to reconstruct the eruption history and magmatic processes of the Piedra Parada Caldera. In the early Eocene, the crystal-poor Barda Colorada ignimbrite(BCI), having >>15% micro-porphyritic crystals with respect to magmatic components, erupted a volume estimated in more than 300 km^3. The Piedra Parada caldera is located in the Patagonian Andes foreland, at the southern end of the calderas field of the Pilcaniyeu Volcanic Belt(PVB). This belt is related to an extensional tectonic setting as a result of the collision of the Farallon-Aluk ridge with South America, which enabled the development of a transform ocean/continental plate margin followed by the detachment of the Aluk plate and the opening of a slab window. The BCI extra-caldera Plateau is a >100 m thick deposit, having a lower unit with high silica(Si O_2> 76 wt.%),potassium poor rhyolitic composition(trondhjemitic like magma), and an upper unit with normal to high potassium rhyolitic composition(granitic like magma). A trace elements modeling of the BCI units shows that the BCI lower and upper units did not evolve from fractionation or immiscibility in the shallow magma reservoir. The BCI also have a primitive isotopic signature(initial87 Sr/86 Sr =0.7031-0.7049 and ε_(Nd)= +3.4 to +3.65). Thus, tectonic, compositional and isotopic constraints suggest the fast ascent of high silica magmas to a shallow reservoir, and point to an upper mantle origin for these rhyolitic magmas in a transitional(Orogenic-Anorogenic) tectono-magmatic setting. U-Th-Pb SHRIMP zircon crystallization ages of the Syn-caldera stage BCI units(56 -51.5 Ma) show a protracted life of 5 Ma for this caldera reservoir. The age of 52.9 ± 0.3 Ma is considered the best fit for the possible maximum age for the caldera collapse. The Late-caldera magmatism has trachyandesitic and rhyolitic *** trace element modeling suggests that these rhyolites evolv

关键词： Mantle derived rhyolite Crystal-poor ignimbrite Bimodal volcanism Slab window volcanism K poor-rhyolite

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Some Smoothness Results for Classical Problems in Optimal Design and Applications

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 703-714页

作者： juan CASADO-diaz Dpto.de Ecuaciones Diferenciales y Analisis Numerico University of Seville41012 SevillaSpain

The author considers two classical problems in optimal design consisting in maximizing or minimizing the energy corresponding to the mixture of two isotropic materials or two-composite material. These results refer to... 详细信息

关键词： Optimal design Two-phase material Non-existence Relaxation

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Hot corrosion mechanism of yttria-stabilized zirconia powder in the presence of molten Na_(2)SO_(4)+V_(2)O_(5) salts

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Rare Metals 2021年第5期40卷 1307-1316页

作者： Jhonattan De la Roche juan Manuel alvarado-Orozco Alejandro Toro Tribology and Surfaces Group Universidad Nacional de ColombiaMedellin 050041Colombia Centro de Ingeniena y Desarrollo Industrial-CIDESI Queretaro 76125Mexico Consorcio de Manufactura Aditiva-CONMAD Queretaro 76125Mexico

The hot corrosion behavior of yttria-stabilized zirconia(YSZ)powder specimens exposed to Na_(2)SO_(4)/V_(2)O_(5) salts mixtures at high temperature was *** tests were carried out at 1000℃ for 10 h,the salt concentrations varied from 0.1 wt%to 1.00 wt%,and the Na_(2)SO_(4)/V_(2)O_(5) mass ratios were between 0.20 and 0.44 following a factorial design 22.X-ray diffraction(XRD)analyses of the tested samples showed with a confidence of95%that the mixture composed of 32 wt%Na_(2)SO_(4)+68 wt%V_(2)O_(5),and 1.00 wt% salt concentration led to high destabilization of the t’-YSZ phase and formation of YVO_(4) products.A second set of experiments were conducted to assess the influence of temperature on the hot corrosion response of the YSZ in the range between 490 and 1100℃.Thermogravimetric analysis(TGA)experiments and Rietveld adjustments of XRD patterns showed that the mass loss of the samples varied with testing temperature and also that the major destabilization of tetragonal phase occurred at 900℃.

关键词： Hot corrosion Molten salts Yttria-stabilized zirconia Thermal barrier coatings

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Female control of sperm ejection and retention in the cornsilk fly Euxesta eluta(Diptera:Ulididae)

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Insect Science 2023年第4期30卷 1183-1190页

作者： Solana Abraham Andrea Moyano Viviana diaz MGabriela Murua juan Rull Laboratorio de Investigaciones Ecoetologicas de Moscas de la Fruta y sus Enemigos Naturales(LIEMEN) PROIMI-BiotecnologiaCONICETTucumanArgentina Instituto de Tecnologia Agroindustrial del Noroeste Argentino(ITANOA) Estacion Experimental Agroindustrial Obispo Colombres(EEAOC)—CONICETTucumanArgentina

Promiscuous mating systems provide the opportunity for females to bias fertilization toward particular ***,distinguishing between male sperm com-petition and active female sperm choice is difficult for species with internal ***,species that store and use sperm of different males in different storing struc-tures and species where females are able to expel all or part of the ejaculates after cop-ulation may be able to bias *** report a series of experiments aimed at pro-viding evidence of female sperm choice in Euxesta eluta(Hendel),a species of ulidiid fly that expels and consumes ejaculates after *** found no evidence of greater reproductive success for females mated singly,multiply with the same male,or mated multiply with different *** *** possesses two spherical spermathecae and a bursa copulatrix for sperm storage,with a ventral *** was no significant difference in storing more sperm in spermathecae 24 h after copulation than immediately after *** mated with protein-fed males had greater reproductive success than similar females mated to protein-deprived ***-fed females prevented to consume the ejaculate,retained more sperm when mated to protein-fed males than when mated to protein-deprived *** results suggest that female *** can exert control of sperm retention of higher quality males through ejaculate ejection.

关键词： bursa copulatrix cornsilk fly cryptic female choice ejaculate consumption sperm choice spermathecae

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The significance of U-Pb zircon ages in zoned plutons:the case of the Flamenco pluton, Coastal Range batholith, northern Chile

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Geoscience Frontiers 2019年第3期10卷 1073-1099页

作者： Natalia Rodríguez juan Díaz-alvarado Carlos Fernández Paulina Fuentes Christoph Breitkreuz Colombo Celso Gaeta Tassinari Departamento de Geología Universidad de Atacama Departamento de Ciencias de la Tierra Universidad de Huelva Institut für Geologie TU Bergakademie Freiberg High Resolution Geochronological Laboratory University of S?o Paulo

Compositionally zoned plutons, both layered and concentrically arranged, provide granitic exposures where the mechanisms and timing of the magmatic emplacement processes can be studied. The importance of in-situ geochemical differentiation and the magma replenishment rates are revealed by geochemistry and field relations, together with the increasingly accurate U-Pb geochronology, which has promoted the knowledge about the pluton incremental assembly *** Flamenco pluton, located in the Coastal Range of northern Chile, is part of the Upper Triassic to Early Cretaceous Andean intrusives formed in the western active margin of South America, and present a normal zoned structure with mafic magmatic facies(mostly gabbros and Qtz-diorites) close to the contacts with the host metasediments, and tonalites, granodiorites and granites in the inner areas. A combined study of the field relations, geochemistry and zircon geochronology of the magmatic facies was applied to determine the emplacement sequence of the Flamenco pluton, revealing three distinguishable domains separated by metasedimentary septa. The SW area is constituted by mostly homogeneous leucocratic granodiorites that yielded an age of 213 Ma as the best estimation for their emplacement age. Distinctive geochemical characteristics, such as the absence of an Eu anomaly, the depletion in HREE, or the highest Sr, Sr/Y and Ce/Yb values among the granodioritic facies of the pluton,involve lower T and/or higher P conditions at the magmatic source according to experimental *** conditions were established during an early stage of the Andean magmatic arc building that is firstly defined here as Upper Triassic. The NW and E domains of the pluton were sequentially emplaced between 194 Ma and 186 Ma and both the field relations and the detailed geochronological results suggest that the mafic facies intruded latter in the emplacement sequence. To the NW, Qtz-dioritic and gabbroic externally emplaced pulses ga

关键词： Zircon U-Pb geochronology Zoned plutons Andean magmatic arc Sequential emplacement Individual and statistical zircon ages

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Assessing a novel modelling approach with high resolution UAV imagery for monitoring health status in priority riparian forests

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Forest Ecosystems 2021年第4期8卷 810-830页

作者： juan Guerra-Hernandez Ramon A.diaz-Varela juan Gabriel Avarez-Gonzalez Patricia Maria Rodriguez-Gonzalez edata Centro de iniciativas empresariaisFundacion CEL.O Palomar s/n27004 LugoSpain Forest Research Centre School of AgricultureUniversity of LisbonInstituto Superior de Agronomia(ISA)Tapada da Ajuda1349-017 LisbonPortugal Biodiversity and Applied Botany Unit(GI BIOAPLIC 1809) Department of BotanyEscuela Politecnica SuperiorR/Benigno LedoUniversity of Santiago de CompostelaCampus Universitario27002 LugoSpain Sustainable Forest Management Unit(UXFS) Department of Agroforestry EngineeringEscuela Politecnica SuperiorR/Benigno LedoUniversity of Santiago de CompostelaCampus UniversitarioE-27002 LugoSpain

Background:Black alder(Alnus glutinosa)forests are in severe decline across their area of distribution due to a disease caused by the soil-borne pathogenic Phytophthora alni species complex(class Oomycetes),“alder Phytopththora”.Mapping of the different types of damages caused by the disease is challenging in high density ecosystems in which spectral variability is high due to canopy *** obtained by unmanned aerial vehicles(UAVs)may be particularly useful for such tasks due to the high resolution,flexibility of acquisition and cost efficiency of this type of *** this study,*** decline was assessed by considering four categories of tree health status in the field:asymptomatic,dead and defoliation above and below a 50% threshold.A combination of multispectral Parrot Sequoia and UAV unmanned aerial vehicles-red green blue(RGB)data were analysed using classical random forest(RF)and a simple and robust three-step logistic modelling approaches to identify the most important forest health indicators while adhering to the principle of parsimony.A total of 34 remote sensing variables were considered,including a set of vegetation indices,texture features from the normalized difference vegetation index(NDVI)and a digital surface model(DSM),topographic and digital aerial photogrammetry-derived structural data from the DSM at crown ***:The four categories identified by the RF yielded an overall accuracy of 67%,while aggregation of the legend to three classes(asymptomatic,defoliated,dead)and to two classes(alive,dead)improved the overall accuracy to 72% and 91% *** the other hand,the confusion matrix,computed from the three logistic models by using the leave-out cross-validation method yielded overall accuracies of 75%,80% and 94% for four-,three-and two-level classifications,***:The study findings provide forest managers with an alternative robust classification method for the rapid,effective assessment of area

关键词： Alder RPAS Multi-spectral Defoliation Texture variables 3D point cloud Tree health monitoring

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Ballistic impact response of flexible and rigid UHMWPE textile composites:Experiments and simulations

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Defence Technology（防务技术） 2023年第4期22卷 37-53页

作者： Hongxu Wang Dakshitha Weerasinghe Paul J.Hazell Damith Mohotti Evgeny V.Morozov juan P.Escobedo-diaz School of Engineering and Information Technology The University of New South WalesCanberraACT2600Australia

This study elaborates on the effects of matrix rigidity on the high-velocity impact behaviour of UHMWPE textile composites using experimental and numerical *** composite samples were manufactured of a plain-weave fabric(comprising Spectra?1000 fibres)and four different matrix ***-velocity impact tests were conducted by launching a spherical steel projectile to strike on the prepared samples via a gas *** experimental results showed that the textile composites gradually changed from a membrane stretching mode to a plate bending mode as the matrix rigidity and thickness *** composites deformed in the membrane stretching mode had higher impact resistance and energy absorption capacity,and it was found that the average energy absorption per ply was much higher in this mode,although the number of broken yarns was smaller in the perforated ***,the flexible matrix composites always had higher perforation resistance but larger deformation than the rigid matrix counterparts in the tested thickness and velocity range.A novel numerical modelling approach with enhanced computational efficiency was proposed to simulate textile composites in mesoscale *** simulation results revealed that stress and strain development in the more rigid matrix composite was localised in the vicinity of the impact location,leading to larger local deformation and inferior perforation resistance.

关键词： Impact behaviour Textile composite UHMWPE fibre Energy absorption Finite element analysis

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Photosynthetic and Molecular Markers of CO_2-mediated Photosynthetic Downregulation in Nodulated Alfalfa

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Journal of Integrative Plant Biology 2013年第8期55卷 721-734页

作者： Alvaro Sanz-Sez Gorka Erice Iker Aranjuelo Ricardo Aroca juan Manuel Ruíz-Lozano Jone Aguirreolea juan Jos Irigoyen Manuel Sanchez-diaz Department of Plant Biology University of NavarraPamplonaE-31008Spain Department of Plant Biology University of BarcelonaBarcelonaE-8028Spain Department of Plant Biology University of Illinois at Urbana-Champaign61801USA Agrobiotechnology Institute Public University of NavarraMutilva BajaE-31192Spain Department of Soil Microbiology and Symbiotic Systems Zaidin Experimental Station(CSIC)GranadaE-18008.Spain

Elevated CO2 leads to a decrease in potential net photosynthesis in long-term experiments and thus to a reduction in potential growth. This process is known as photosynthetic downregulation. There is no agreement on the definition of which parameters are the most sensitive for detecting CO2 acclimation. In order to investigate the most sensitive photosynthetic and molecular markers of CO2 acclimation, the effects of elevated CO2, and associated elevated temperature were analyzed in alfalfa plants inoculated with different Sinorhizobium meliloti strains. Plants （Medicago sativa L. cv. Aragon） were grown in summer or autumn in temperature gradient greenhouses （TGG）. At the end of the experiment, all plants showed acclimation in both seasons, especially under elevated summer temperatures. This was probably due to the lower nitrogen （N） availability caused by decreased N2-fixation under higher temperatures. Photosynthesis measured at growth CO2 concentration, rubisco in vitro activity and maximum rate of carboxylation were the most sensitive parameters for detecting downregulation. Severe acclimation was also related with decreases in leaf nitrogen content associated with declines in rubisco content （large and small subunits） and activity that resulted in a drop in photosynthesis. Despite the sensitivity of rubisco content as a marker of acclimation, it was not coordinated with gene expression, possibly due to a lag between gene transcription and protein translation.

关键词： Carbon dioxide Medicago sativa (alfalfa) photosynthetic downregulation RbcL and RbcS Sinorhizobium meliloti.

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Promiscous female Euxesta eluta derive nutrients for ovarian development by expelling and consuming ejaculates

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Insect Science 2020年第3期27卷 545-557页

作者： Solana Abraham Gisela Castillo Viviana diaz Guido Van Nieuwenhove Gabriela Murua juan Rull Laboratorio de Investigaciones Ecoetologicas de Moscas de la Fruta y sus Enemigos Naturales(LIEMEN) PROIMI-BiotecnologiaCONICETTucumanArgentina Fundacion Miguel Ullo Instde EntomologiaDepto ZoologiaMiguel Lillo 251San Miguel de TucumanTucumanArgentina Facultad de Ciencias Naturales e I.M.L Universidad Nacional de TucumanSan Miguel de TucumanTucumanArgentina Estacion Experimental Agroindustrial Obispo Colombres(EEAOC)_ITANOA CONICET TucumanArgentina

Seminal gifts range from important material donations to items that provide little direct benefit to ***,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after *** evolution and function of this peculiar behavior are currently *** performed a series of experiments aimed to:determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption,if males suffer a fitness cost from supplying females with ejaculates,and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior *** revealed that protein deprived *** females derive nutrients for ovarian development through consumption of ejaculates of protein fed *** seminal products affecting survival appear to be transferred in the consumed ***,ovarian development,in contrast to testes growth,occurs in detriment of *** preferred to mate with protein fed males,yet sperm retention in spermathecae was extremely rare after a single *** finding suggests that females could be exerting post copulatory control.A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.

关键词： anautogeny polyandry postcopulatory female control seminal gifts sperm storage

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META-R:A software to analyze data from multi-environment plant breeding trials

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The Crop Journal 2020年第5期8卷 745-756页

作者： Gregorio alvarado Francisco M.Rodríguez Angela Pacheco juan Burgueño JoséCrossa Mateo Vargas Paulino Pérez-Rodríguez Marco A.Lopez-Cruz Biometrics and Statistics Unit International Maize and Wheat Improvement Center(CIMMYT)MexicoDF 6-64106600Mexico Centro de Investigación en Matemáticas(CIMAT)A.C. Jalisco S/NCol.ValencianaGuanajuatoGto 40236023Mexico Universidad Autónoma Chapingo Carretera Federal México-Texcoco km 38.5TexcocoMéxico 6356230Mexico Colegio de Postgraduados Carretera México-Texcoco Km.36.5MontecilloTexcoco 6356231Mexico Department of Plant Soil and Microbial SciencesMichigan State University1066 Bogue StEast LansingMI 48824USA

META-R(multi-environment trial analysis in R)is a suite of R scripts linked by a graphical user interface(GUI)designed in Java *** objective of META-R is to accurately analyze multi-environment plant breeding trials(METs)by fitting mixed and fixed linear models from experimental designs such as the randomized complete block design(RCBD)and the alpha-lattice/lattice ***-R simultaneously estimates the best linear and unbiased estimators(BLUEs)and the best linear and unbiased predictors(BLUPs).Additionally,it computes the variance-covariance parameters,as well as some statistical and genetic parameters such as the least significant difference(LSD)at 5%significance,the coefficient of variation in percentage(CV),the genetic variance,and the broad-sense *** parameters are very important in the selection of top performing genotypes in plant ***-R also computes the phenotypic and genetic correlations among environments and between traits,as well as their statistical *** genetic correlations between environments or traits can be visualized in a biplot graph or a tree diagram(dendrogram).Genetic correlations are very important for identifying environments with similar behavior or making indirect selection and identifying the most highly associated ***-R performs multi-environment analyses by using the residual maximum likelihood(REML)method;these analyses can be done by environment,across environments by grouping factors(stress conditions,nitrogen content,etc.)and across environments;the analyses across environments can be done with a pre-defined degree of heritability.

关键词： environments breeding variance

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