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Experimental Characterization of the Supersonic Transitional Wake Downstream of a Single Roughness Element

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Journal of Thermal Science 2020年第4期29卷 1085-1093页

作者： BOTTINI Henny SARACOGLU Bayindir H. PANIAGUA Guillermo Department of Aerospace Engineering Nagoya UniversityNagoya 464-8603Japan Aeronautics and Aerospace Department von Karman Institute for Fluid DynamicsRhode-Saint-Genese B-1640Belgium Zucrow Laboratories Purdue University500 Allison RoadWest Lafayette 47907INUSA

An experimental campaign was carried out to investigate the characteristics of the transitional supersonic wake downstream of a single roughness element. Two Mach numbers were tested, 1.6 and 2.3, and two roughness heights, 0.1 mm and 1 mm. Unsteady and steady wall temperature measurements were taken along and across the roughness wake. The spatial trends of adiabatic wall temperature and heat flux, and the spectral time evolution of temperature were documented in this paper. The initial wall temperature was varied during the temperature measurements, and the resulting steady and unsteady effects on the roughness wake were investigated. The streamwise trends of heat-flux and adiabatic-wall temperature confirmed the transitional nature of the roughness wake. Spectral analysis showed that roughness height and initial wall temperature had the same type of effect on the wake wall-temperature fluctuations. The effect of roughness height was more sensible at Mach 2.3, and that of the initial wall temperature was more evident with the smallest roughness also tested at Mach 2.3.

关键词： supersonic boundary layer roughness wake steady measurements unsteady measurements heat transfer

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 dynamics.Most 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 variables.However,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 vultures.Here,we explore individual and environmental factors potentially affecting the secondary sex ratio of the monomorphic griffon vulture Gyps fulvus.We 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 sex.Sex ratio did not differ from parity either at the population or the nuclei level.No significant between-year differences were detected,even under highly changing conditions of food availability associated with the mad-cow crisis.We 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 examination.Whereas 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

The architecture of the(post)studio:Jackson Pollock’s barn and Andy Warhol’s Silver Factory

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Frontiers of Architectural Research 2023年第2期12卷 266-276页

作者： guillermo Lockhart Milan Departamento de Proyectos Arquitecto´nicos Escuela Te´cnica Superior de ArquitecturaUniversidad Polite´cnica de MadridMadrid 28040Spain

This article will discuss a false dichotomy between two models,the modern art studio and the post-studio,which oppose the private and the public,the individual and the collective,hiding and the revealing.We will begin by analysing Daniel Buren’s position in his canonical text“Fonction de l’Atelier”and his practice,where the artist defines the foundations of post-studio work.As the text also describes a New York studio type that must be left behind,we will analyse Jackson Pollock’s and Andy Warhol’s workspaces through drawing reconstructions to demonstrate that these meet the defining characteristics of both models.It will be shown that the artists have used design strategies to retain certain aspects of studio culture while exploring others of the post-studio.This turning point reveals that the current belief about the obsolescence of the studio in a global era defined by communication,networking and mobility ignores its emerging post-studio qualities.This work aims to acknowledge this shift,obtaining a critical vision that will allow us to design contemporary workspaces avoiding stereotypical and reductionist approaches.

关键词： Andy Warhol Daniel Buren Function of the studio Jackson Pollock Post-studio Studio

Interspecific differences in plasma carotenoid profiles in nestlings of three sympatric vulture species

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Current Zoology 2023年第6期69卷 658-669页

作者： guillermo Blanco Damaso Hornero-Mendezb Department of Evolutionary Ecology Museo Nacional de Ciencias Naturales(CSIC)Jose Gutierrez Abascal 228006 MadridSpain Departament of Food Phytochemistry Instituto de la Grasa(CSiC)Campus Universidad Pablo de Olavide41013 SevilleSpain

Carotenoids are diet-based micronutrients important in health and coloration signaling.Related species with similar diets can differ in the kinds and levels of circulating carotenoids,which suggests specific physiological mechanisms to efficiently utilize these micronutrients,regardless of their availability.We explored whether diet and parental provisioning of unusual sources of carotenoids(fresh vegetal matter and vertebrate feces)can explain the occurrence and concentrations of carotenoids in the cinereous vulture Aegypius monachus,griffon vulture Gyps fulvus,and Egyptian vulture Neophron percnopterus nestlings,even when these pigments appear to not be deposited in their integumentary system.A greater diversity of wild prey in diet could be behind the profile of higher concentrations of carotenoids in the Egyptian vulture,the species with carotenoid-dependent coloration during adulthood,while differences in diet composition between cinereous and griffon vultures do not translate to different carotenoid profiles.The carotenoid profile appears to not be related to the ingestion of unusual matter rich in these compounds,although the infrequent occurrence of lycopene and unidentified y-carotene-like compounds suggest that these vultures may be exploiting vegetal matter that left no identifiable unconsumed remains in the nest of Egyptian vultures.The consumption of green plant material by griffon vultures does not result in especially high levels of carotenoids when compared to the carotenoids found in cinereous vultures,which do not consume green plant material.Ungulate feces were not provisioned to Egyptian vulture nestlings,despite the fact they contain carotenoids that adults need for appropriate coloration.Overall,this study indicates that diet differences alone appear insufficient to explain contrasting inter.specific carotenoid profiles,especially since all types of food consumed are considered to be poor in carotenoids,except vegetable matter.We suggest that nestling Egyptian vultures are comparatively effi

关键词： avian scavengers carotenes coloration feeding habits micronutrients xanthophylls

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 systems.Soil cementation is a ground improvement technique that can increase the interparticle contact area,leading to a high effective thermal conductivity.However,cementation may occur at different locations in the soil matrix,i.***.interparticle contacts,evenly or unevenly around particles,in the pore space or a combination of these.The topology of cementation at the particle scale and its influence on soil response have not been studied in detail to date.Additionally,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 research.In 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 transfer.The effective thermal conductivity of each sample was computed using a thermal conductance network model.Results 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

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 out.In each cubic element,we determine the gas particles with a normalized density greater than an arbitrarily chosen density threshold.By using a proximity parameter,we calculate the neighboring cubic elements and generate a list of neighbors.By 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

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 gas.We 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 profile.Additionally,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 passage.To allow comparison with the galaxy model,we characterize the dynamics of the collision models in an analogous way.Finally,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 trajectory.To 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

Maize defense against insect herbivory:A novel role for 9-LOX-derived oxylipins

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Molecular Plant 2023年第10期16卷 1484-1486页

作者： guillermo H.Jimenez-Aleman Georg Jander Boyce Thompson Institute 533 Tower RoadIthacaNY 14853USA

Up to 40%of global crops are destroyed by arthropod pests,either prior to harvest or during storage(Gullino et al.,2021).This problem is exacerbated by current and anticipated climatechanges that will allow the long-term survival of pest populationsin new habitats,as well as by the introduction of new pest speciesinto areas where they were not previously present.For instance,the recent introduction of Spodoptera frugiperda(fall armyworm),which previously was a major pest of Zea mays(maize)only in theAmericas,led to the expansion of this species throughout themaize-growing regions of Africa and Asia in less than 5 years(Tay et al.,2022).

关键词： crops destroyed instance

Oral disease is linked to low nestling condition and brood size in a raptor species living in a highly modified environment

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Current Zoology 2023年第2期69卷 109-120页

作者： guillermo Blanco Oscar Frias Aida Pitarch Martina Carrete Department of Evolutionary Ecology Museo Nacional de Ciencias NaturalesCSiC.Jose Gutierrez Abascal 2Madrid 28006Spain Department of Physical Chemical and Natural SystemsUniversidad Pablo de OlavideSevilla 41013Spain Department of Microbiology and Parasitology Faculty of PharmacyComplutense University of Madrid(UCM)and Ramon y Cajal Institute of Health Research(IRYCIS)Madrid 28040Spain Teaching Unit of Microbiology and Parasitology Faculty of Optics and OptometryComplutense University of Madrid(UCM)Madrid 28037Spain

Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens,making the epizootiology of environmental diseases difficult to unravel.The incidence and impact of oral lesions in nestlings of a facultative scavenger species,the black kite Milvus migrans,were examined over seven breeding seasons in the highly degraded environment close to Madrid,Spain.We found an overall prevalence of 31%of nestlings with oral lesions,with no clear spatial pattern in nests with affected and unaffected individuals.The occurrence and number of oral lesions were negatively associated with nestling body condition and brood size.Broods,where all siblings had oral lesions,were smaller than those where some or all siblings were apparently healthy,suggesting that oral disease could be causing nestling mortality and,consequently,brood size reduction.In turn,nestling body condition was negatively affected by lesion occurrence,brood size,and laying date.Although these relationships were bidirectional,piecewise structural equation modeling analyses showed a greater negative effect of body condition on lesion occurrence than vice versa,indicating that nestlings in poorer body condition were more likely to develop oral lesions(which could contribute to aggravate their state of deterioration)than those in better condition.Nestlings from small broods were also more likely to have oral disease(directly or indirectly through their lower body condition)than nestlings from large broods.Nestlings that hatched last in the broods showed greater development stress than those that hatched first.Anthropogenic stressors could trigger poor body condition,and contribute to microbiota dysbiosis-related diseases.Although further research is needed to determine the consequences for the long-term fitness of individuals,actions should be taken to mitigate adverse conditions that may favor the appearance of environmental diseases associatedwithperi-urbanareas,giventheirrapidexpansion overnatur

关键词： breeding success body condition developmental stress environmental disease habitat degradation opportunistic pathogens pollution raptor