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Macrobioerosion and Microbioerosion in Marine Molluscan Shells from Holocene and Modern Beaches (39°-40°S, South of Buenos Aires Province, Argentina)

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1215-1230页

作者： Melisa P. CHARO Jose L. CAVALLOTTO guillermo acenolaza Instituto Superior de Correlacion Geologica (INSUGEO/CONICET-UNT) Miguel Lillo 205 4000 Tucuman Argentina Servicio de Hidrografia Naval Av. Montes de Oca 2124 C1270ABWBuenos Aires Argentina

The marine sediments of the area of Verde Peninsula - Jabali Island （39°28＇S/62°19%V-40°28＇ S/62°11＇W） Holocene in age （3-2 ky）, and modern beaches contain a significant amount of bioeroded mollusc shells. Fifteen sites were analyzed, in which 20.11% of the mollusc shells （2168 valves） presented bioerosion traces, in 54 species （30 bivalves and 24 gastropods）. Fourteen ichnogenera were reported： Entobia, Maeandropolydora, Iramena, Caulostrepsis, Pennatichnus, Pinaceocladichnus, Trypanites, and Gastrochaenolites （Domichnia）, Gnathichnus and Radulichnus （Pascichnia）, Finichnus and Centrichnus （Fixichnia）, Oichnus （Praedicnia）（macrobioerosion）, y Semidendrina （microbioerosion）, the latter is first reported in mollusc shells in Argentina. Eleven ichnospecies were identified Finichnus peristroma, Maeandropolydora sulcans, Gnathichnus pentax, Pinaceocladichnus onubensis, Caulostrepsis taeniola, Centrichnus eccentricus, Radulichnus inopinatus, Oichnus simplex, Oichnus paraboloides, Oichnus gradatus, and Gastrochaenolites torpedo （lithic remains）. The dominant ichnogenera in the Holocene deposits are Iramena, Entobia and Oichnus. The same ichnogenera are constant with different abundance in the modern beaches, and increasing representation of Pinaceocladichnus and Pennatichnus. The dominant ichnofacies in the Holocene deposits is Trypanites, revealing a benthonic marine community composed of cheilostome bryzoans, clionaid sponges, predator gastropods, regular echinoids, polychaete annelids, bivalves, thallophytas and fungi. Generally, the area was described as a sublittoral, low-energy, stable environment with high rate of oxygenation, and sandy bottoms, with rocky bottoms at Villalonga locality.

关键词： molluscan bioerosion Holocene south of Buenos Aires Province

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Depositional Controls on the Ichnology of Ordovician Wave-dominated Marine Facies：New Evidence from the Shirgesht Formation,Central Iran

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1572-1597页

作者： Aram BAYET-GOLL Paul M.MYROW guillermo F.acenolaza Reza MOUSSAVI-HARAMI Asadollah MAHBOUBI Department of Earth Sciences Institute for Advanced Studies in Basic Sciences (IASBS) P.O. Box 45195 -1159 Zanjan Iran Department of Geology Faculty of Science Ferdowsi University ofMashhad Iran Department of Geology The Colorado College 14 E. Cache La Poudre Colorado Springs Colorado 80903 U.S.A. INSUGEO (Instituto Superior de Correlacidn Geologica) CONICET- National University of Tucuman Argentina

The Lower Ordovician Shirgesht Formation in central Iran is composed of siliciclastic and carbonate rocks deposited in diverse coastal and marine shelfal environments（tidal flat,lagoon,shoreface,offshore-shelf and carbonate ramp）.Five facies associations contain diverse ichnofossil assemblages that show distinct proximal to distal trends formed in a wide range of physical-chemical *** ethological groups of trace fossils in the Shirgesht Formation reflect a gradient of depositional stress conditions across a wave-influenced shoreline and *** of waveinfluenced environments make up a significant component of the geological record of shallow marine settings,and the ability to determine paleoenvironments in detail in such successions is critical for reconstruction of depositional histories and sequence-stratigraphic *** Cruziana ichnofacies of the study shows highly diverse suites that record the establishment of a benthic community under stable conditions and a long-term colonization *** Skolithos ichnofacies recognized is a low diversity opportunistic ichnocommunity suite that resulted from colonization after tempestite deposition in a stressed *** strata record an onshore to offshore replacement of the Cruziana ichnofacies（with abundant feeding traces of deposit-feeders） by the Skolithos ichnofacies（dominated by suspension-feeders and predators）.A transitional zone between the two ichnofacies coincides with the offshore-transition/distal lower-surface *** distribution of ichnofacies,the diversity and range of ethological characteristics reflected by the ichnogenera,and the wide range of wave-dominated coastal facies demonstrate the potential to use individual trace fossils and ichnofacies for significantly refined palaeoenvironmental analysis of wavedominated coastal settings,particularly in Ordovician successions.

关键词： Shirgesht Formation Ordovician facies associations sedimentology iconology ichnofacies

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US children with special health care needs and ethnic discrimination: results from multivariate modeling

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World Journal of Pediatrics 2019年第2期15卷 182-189页

作者： guillermo Montes St.John Fisher College Alesi 106C3690 East Ave.RochesterNY 14618USA Children's Institute Inc. RochesterNYUSA

Background To determine the prevalence of parent-reported ethnic/racial discrimination,and to determine if children with special health care needs are more likely to experience ethnic discrimination than other children who have similar family income,age,sex,race,parental education and Hispanic *** Using the National Survey of Children's Health 2011-2012 (n =95,677),ethnic discrimination was measured by two questions that asked 'was child ever treated or judged unfairly because of his/her race or ethnic group?' and if so,how often it occurred in the last 12 months prior to the *** An estimated 3 million US children aged 0-17 years have experienced parent-reported ethnic discrimination (1.4% White,9.1% Black,9.9% other race,4.7% Hispanic).The likelihood to experience ethnic discrimination is much higher for Black and other race children,compared to White *** with special health care needs were two times more likely to experience ethnic discrimination frequently in the 12 months prior to the survey than comparable children in terms of age,sex,race,family income,parental education,and social *** family income did not prevent the exposure to ethnic discrimination but was associated with fewer *** Theoretical frameworks,such as social determinants of health,must account for the bidirectional nature of the relationship between health and ethnic *** care must assess if ethnic discrimination has occurred and whether trauma-informed approaches are needed.

关键词： Children with special health care needs Ethnic discrimination United States

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A thick-disk galaxy model and simulations of equal-mass galaxy pair collisions

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Research in Astronomy and Astrophysics 2020年第11期20卷 333-353页

作者： guillermo Arreaga-Garcıa Departamento de Investigacion en Fsica Universidad de Sonora.Apdo.Postal 14740C.P.83000HermosilloSonoraMexico

We implement a numerical model reported in the literature to simulate the evolution of a galaxy composed of four matter components,such as:a dark-matter halo;a rotating disk of stars;a spherical bulge of stars and a ring of molecular *** show that the evolution of this galaxy model is stable at least for 10 Gyr(Gyr=109 years).We characterize the resulting configuration of this galaxy model by figures of the circular velocity and angular momentum distribution;the tangential and radial components of the velocity;the peak density evolution and the radial density ***,we calculate several models of equal-mass galaxy binary collisions,such as:(i)frontal and(ii)oblique(with an impact parameter),(iii)two models with initial conditions taken from a 2-body orbit and(iv)a very close *** allow comparison with the galaxy model,we characterize the dynamics of the collision models in an analogous ***,we determine the de Vaucouleurs fitting curves of the radial density profile,on a radial scale of 0–100 kpc,for all the collision models irrespective of the pre-collision *** study the radial mass density and radial surface density profiles at a smaller radial scale,0–20 kpc,we use a four-parameter fitting curve.

关键词： galaxies kinematics and dynamics galaxies interaction methods numerical

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Empirical formulae to describe some physical properties of small groups of protogalaxies with multiplicity

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Research in Astronomy and Astrophysics 2021年第8期21卷 141-158页

作者： guillermo Arreaga-Garcia Departamento de Investigacion en Fisica Universidad de Sonora Apdo.Postal 14740C.P.83000HermosilloSonoraMexico

By means of identical cubic elements,we generate a partition of a volume in which a particle-based cosmological simulation is carried *** each cubic element,we determine the gas particles with a normalized density greater than an arbitrarily chosen density *** using a proximity parameter,we calculate the neighboring cubic elements and generate a list of *** imposing dynamic conditions on the gas particles,we identify gas clumps and their neighbors,so that we calculate and fit some properties of the groups so identified,including the mass,size and velocity dispersion,in terms of their multiplicity(here defined simply as the number of member galaxies).Finally,we report the value of the ratio of kinetic energy to gravitational energy of such dense gas clumps,which will be useful as initial conditions in simulations of gravitational collapse of gas clouds and clusters of gas clouds.

关键词： galaxies:kinematics and dynamics hydrodynamics methods:numerical

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Over 9% efficiency achieved for all-polymer solar cells processed by a green solvent

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Science China Chemistry 2017年第8期60卷 1109-1110页

作者： guillermo C.Bazan Departments of Chemistry ＆ Biochemistry and Materials University of California Santa Barbara CA 93106 USA

Bulk-heterojunction polymer solar cells （PSCs） have at- tracted considerable attention owning to their potential for fabricating flexible, light-weight and large area solar cell panels via high-throughput roll-to-roll technologies. Compared with conventional PSCs comprising small mol- ecule acceptors, such as fullerenes, all-polymer solar cells （all-PSCs） containing blends of p-type/n-type polymers in the photoactive layer provide advantages including easily tunable absorption band, enhanced absorption coefficient,

关键词： PSCs on in is for efficiency achieved for all-polymer solar cells processed by a green solvent Over 9 by

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Estimation of thermal conductivity of cemented sands using thermal network models

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 210-218页

作者： Wenbin Fei guillermo A.Narsilio Department of Infrastructure Engineering The University of MelbourneParkvilleAustralia

Effective thermal conductivity of soils can be enhanced to achieve higher efficiencies in the operation of shallow geothermal *** cementation is a ground improvement technique that can increase the interparticle contact area,leading to a high effective thermal ***,cementation may occur at different locations in the soil matrix,*** contacts,evenly or unevenly around particles,in the pore space or a combination of *** topology of cementation at the particle scale and its influence on soil response have not been studied in detail to ***,soils are made of particles with different shapes,but the impact of particle shape on the cementation and the resulting change of effective thermal conductivity require further *** this work,three kinds of sands with different particle shapes were selected and cementation was formed either evenly around the particles,or along the direction parallel or perpendicular to that of heat *** effective thermal conductivity of each sample was computed using a thermal conductance network *** show that dry sand with more irregular particle shape and cemented along the heat transfer direction will lead to a more efficient thermal enhancement of the soil,i.e.a comparatively higher soil effective thermal conductivity.

关键词： Network Cementation Computed tomography Ground improvement Sands

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Using Cartesian Slice Plots of a Cosmological Simulation as Input of a Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第11期24卷 225-242页

作者： guillermo Arreaga-García Departamento de Investigación en Física Universidad de Sonora.Apdo.Postal 14740C.P.83000HermosilloSonoraMexico

Using a uniform partitioning of cubic cells,we cover the total volume of aΛCDM cosmological simulation based on *** define a visualization cell as a spatial extension of the cubic cell,so that we collect all simulation particles contained in this visualization cell to create a series of Cartesian plots in which the overdensity of matter is clearly *** then use these plots as input to a convolutional neural network(CNN)based on the Keras library and TensorFlow for image *** assign a class to each plot,we approximate the Hessian of the gravitational potential in the center of the cubic *** selected cubic cell is then assigned a label of 1,2 or 3,depending on the number of positive eigenvalues obtained for the Householder reduction of the Hessian *** apply the CNN to several models,including two models with different visualization volumes,one with a cell size of type L(large)and the other with a cell type S(small).A third model combines the plots of the previous L and S cell *** far,we have mainly considered a slice parallel to the XY plane to make the *** last model is considered based on visualizations of cells that also include slices parallel to the ZX and ZY *** find that the accuracy in classification plots is acceptable,and the ability of the models to predict the class works *** results allow us to demonstrate the aim of this paper,namely that the usual Cartesian plots contain enough information to identify the observed structures of the cosmic web.

关键词： methods numerical cosmology theory (cosmology:)large scale structure of universe

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Nestling sex ratio is unaffected by individual and population traits in the griffon vulture

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Current Zoology 2023年第3期69卷 227-235页

作者： guillermo Gomez-Lopez Felix Martinez Ana Sanz-Aguilar Martina Carrete guillermo Blanco Department of Evolutionary Ecology National Museum of Natural Sciences(MNCN)Spanish National Research Council(CSiC)Jose Gutierrez Abascal 228006 MadridSpain Escuela Internacional de Doctorado Universidad Rey Juan Carlos(URJC)Tulipan s/n28933 MostolesMadridSpain Animal Demography and Ecology Group Institut Mediterrani d'Estudis Avangats(IMEDEA)Miquel Marques 217020 EsporlesMallorcaSpain Applied Zoology and Conservation Group Universitat de les Illes Balears(UIB)Ctra.De Valldemossa km.7.507122PalmaSpain Department of Physical Chemical and Natural SystemsUniversidad Pablo de Olavide(UPO)Ctra.de Utrera km.141013 SevillaSpain

Variation in offspring sex ratios is a central topic in animal demography and population *** studies have focused on bird species with marked sexual dimorphism and multiple-nestling broods,where the offspring sex ratio is often biased due to different individual or environmental ***,biases in offspring sex ratios have been far less investigated in monomorphic and single-egg laying species,and few studies have evaluated long-term and large-scale variations in the sex ratio of nestling ***,we explore individual and environmental factors potentially affecting the secondary sex ratio of the monomorphic griffon vulture Gyps *** used information collected at three breeding nuclei from central Spain over a 30-year period(1990–2020)to analyse the effects of nestling age,parental age,breeding phenology,conspecific density,population reproductive parameters,and spatial and temporal variability on nestling *** ratio did not differ from parity either at the population or the nuclei *** significant between-year differences were detected,even under highly changing conditions of food availability associated with the mad-cow *** found that tree nesting breeders tend to have more sons than daughters,but as this nesting behavior is rare and we consequently have a small sample size,this issue would require additional *** further research is needed to assess the potential effect of breeder identity on nestling sex ratio,this study contributes to understanding the basic ecology and population dynamics of Griffon Vultures,a long-lived species with deferred maturity and low fecundity,whose minor deviations in the offspring sex ratio might imply major changes at the population level.

关键词： offspring sex ratio nestling sex Gyps fulvus monomorphism mad-cow crisis demography

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Design and optimization of supersonic turbines for detonation combustors

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Chinese Journal of Aeronautics 2022年第11期35卷 33-44页

作者： Jorge SOUSA Elena COLLADO-MORATA guillermo PANIAGUA Flemish InstituteforTechnological Research Mol 2400Belgium Commissariat à lénergie atomique et aux énergies alternatives Le Barp 33114France Mechanical Engineering Purdue UniversityWest-Lafayette IN 47906USA

Detonation-based engines offer a potential surge in efficiency for compact thermal power systems. However, these cycles require ad-hoc components adapted to the high outlet velocity from the detonation combustors. This paper presents the design methodology of turbine stages suitable for supersonic inlet conditions and provides a detailed analysis of optimized turbine geometries. A reduced-order solver examines the supersonic blade rows’ functional design space, quantifies the turbine’s non-isentropic performance, and budgets the turbine loss for different optimized leading-edge designs and chord to pitch ratios. The shock-wave interactions were identified as the predominant contributor to turbine losses, and optimal pitch-chord ratios were determined for various inlet Mach numbers. Finally, with this tool, the specific-power output for a wide range of design configurations was computed;and the metal angle that ensures flow starting and maximizes power extraction was calculated. The detailed numerical study describes the flow interactions in a supersonic turbine and offers new correlations to guide the design of future supersonic turbines.

关键词： Rotating detonation Shock waves Supersonic flow Turbines Unstarting

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