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Contrasting levels of genotype by environment interaction for life history and morphological traits in invasive populations of Zaprionus indianus(Diptera:Drosophilidae)

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Insect Science 2020年第5期27卷 1090-1100页

作者： Nicolas J.Lavagnino Marcos Imberti Victoria E.Ortizj Nicolas Flaibani Juan Jose Fanara Laboratorio de Evolucion Departamento de EcologiaGenetica y EvolucidnFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresArgentina IEGEBA-CONICET Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresArgentina

It has been demonstrated that phenotypic plasticity and genotype by envi-ronment interaction are important for coping with new and heterogeneous environments during *** indianus Gupta(Diptera:Drosophilidae)is an Afrotropical invasive fly species introduced to the South American continent in *** species is generalist and polyphagous,since it develops and feeds in several different fruit *** characteristics of *** suggest that phenotypic plasticity and genotype by environment interaction may be important in this species invasion *** this sense,our aim was to investigate the role of genetic variation for phenotypic plasticity(geno-type by environment interaction)in *** invasion of the South American ***,we quantified quantitative genetic variation and genotype by environment in-teractions of morphological and life history traits in different developmental environments,that is,host *** was done in different populations in the invasive range of ***-anus in *** showed that *** populations have considerable amounts of quantitative genetic ***,genotype by environment interactions was detected for the different traits analyzed in response to the different developmental ***,the amounts and patterns of these parameters differed between *** interpreled these results as the existence of diferences in evolutionary potential be-tween populations that have an important role in the short-and long-term success of the *** invasion process.

关键词： biological invasion genotype by env ironment interaction invaded range life history traits morphological traits Zaprionus indianus

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Mesoscopic model for binary fluids

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Frontiers of physics 2017年第5期12卷 231-239页

作者： C. Echeverria K. Tucci O. Alvarez-Llamoza E. E. Orozco-Guillén5 M. Morales M. G. Cosenza CeSiMo Universidad de Los Andes Mérida 5251 Mérida Venezuela Grupo de Caos y Sistemas Complejos Centro de Fisica Fundamental Universidad de Los Andes Mérida Venezuela departamento de fisica FACYT Universidad de Carabobo Valencia Venezuela facultad de Ingenierla Universidad Católica de Cuenca Ecuador programa Académico de Ingenierla en Energla Universidad Politécnica de Sinaloa 82199 Mazatldn Mexico Programa Académico de Ingenierla en Nanoteenologla Universidad Politécnica de Sinaloa 82199 Mazatldn Mexico

We propose a model for studying binary fluids based on the mesoscopic molecular simulation technique known as multiparticle collision, where the space and state variables are continuous, and time is discrete. We include a repulsion rule to simulate segregation processes that does not require calculation of the interaction forces between particles, so binary fluids can be described on a mesoscopic scale. The model is conceptually simple and computationally efficient; it maintains Galilean invariance and conserves the mass and energy in the system at the micro- and macro-scale, whereas momentum is conserved globally. For a wide range of temperatures and densities, the model yields results in good agreement with the known properties of binary fluids, such as the density profile, interface width, phase separation, and phase growth. We also apply the model to the study of binary fluids in crowded environments with consistent results.

关键词： multiparticle collision dynamics mesoscopic models phase separation interface dynamics

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SYNTHESIS AND PROPERTIES OF HOMOPOLYMER AND COPOLYMERS OBTAINED FROM 1-OCTAdeCENE WITH ZIRCONOCENE CATALYSTS

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Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： Raul Quijada Juan L.Guevara Rene Rojas Franco M.Rabagliati departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization Metallocene Catalytic activity Poly-l-octadecene

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development and screening of(Ca-P-Si-F)-PEO coatings for biodegradability control of Mg-Zn-Ca alloys

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Journal of Magnesium and Alloys 2022年第8期10卷 2220-2237页

作者： Lara Moreno Marta Mohedano Raul Arrabal Endzhe Matykina departamento de Ingeniería Química y de Materiales Facultad de Ciencias QuímicasUniversidad Complutense de Madrid28040 MadridSpain

PEO coatings were developed on MgZnxCayalloys for biomedical applications using different treatment times and a novel transparent electrolyte containing Ca,P,Si and *** characteristics and chemical composition of studied materials were evaluated using scanning electron microscopy,X-ray diffraction and optical *** investigations were performed for uncoated and coated materials using potentiodynamic polarization,electrochemical impedance spectroscopy and hydrogen evolution measurements in three media(0.9wt.%NaCl,α-MEM and inorganic part ofα-MEM).Findings revealed that Zn-rich intermetallics favour the formation of large voids in the ***,P,F and Si are successfully incorporated into the *** consist of crystalline phases(Mg O,Mg F_(2)and Ca,Si-rich compounds)and amorphous *** and organic components ofα-MEM solution accelerate corrosion of the bare substrates but have no significant influence on the corrosion resistance of coated ***,inorganicα-MEM can be considered as an appropriate medium for fast screening of PEO *** relatively small amount of F content in the barrier layer facilitates early failure of the coatings,which show undercoating ***-rich intermetallic particles in the undercoating crevice induce a more aggressive corrosive environment and enhanced micro-galvanic couple effect with the Mg *** leads to faster degradation of the coated alloys compared to the bare substrates.

关键词： Magnesium Biomaterials Plasma electrolytic oxidation Corrosion

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Overcast sky condition prevails on and influences the biometeorology of the tropical Andean Páramos

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Journal of Mountain Science 2023年第1期20卷 78-86页

作者： Paola MONTENEGRO-DÍAZ Rolando CELLERIALVEAR Galo CARRILLO-ROJAS departamento de Recursos Hídricos y Ciencias Ambientales Universidad de CuencaCuenca010207Ecuador facultad de Ingeniería Universidad de CuencaCuenca010207Ecuador facultad de Ciencias Químicas Universidad de CuencaCuenca010207Ecuador

Clouds play a major role in modulating the biometeorological processes. We studied the influence of cloudiness on four biometeorological variables:daily air temperature(Tair), relative humidity(RH),reference evapotranspiration(ETr),and photosynthetic active radiation(PAR), recorded at four sites of Andean Páramos in southern Ecuador during 2.5 to 5.5 years. First, we quantified both the cloud cover percentage(Cloud%) creating cloud masks over the visible bands of Landsat 7 images and the sky condition(K_(T)) using the records of solar and extraterrestrial radiation. Second, we estimated KTfrom Cloud%. Finally, we quantified T_(air), RH, ET_(r), and PAR under clear, cloudy, and overcast K_(T) and their dependence on KT. The average Cloud% ranged between 65%–76%, and KTcorroborated the prevailing overcast sky(between 55% and 72.5% of the days) over the páramos. The proposed model performed well in the sites of calibration(R^(2)= 0.80;MBE = 0.00;RMSE = 0.05) and validation(R^(2)= 0.74;MBE =-0.07;RMSE = 0.11). The overcast sky diminished T_(air)(≤ 10℃), ET_(r)(≤ 1.6 mm day-1), and PAR(4 MJ m^(-2)day^(-1)) and increased RH(≥ 88%),while the variables showed the opposite behavior during the uncommon clear sky(≤ 5.5% of the days).Thus, mostly the dynamic of RH(R^(2)≥ 0.62), ETr(R^(2)≥ 0.85), and PAR(R2≥ 0.77) depended on K_(T). Hence,the prevailing overcast sky influenced the biometeorology of the páramos.

关键词： Cloudiness indicator Clearness index Satellite imagery Tropical Andes

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Lower marine productivity increases agonistic interactions between sea lions and fur seals in Northern Pacific Patagonia

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Current Zoology 2022年第6期68卷 657-666页

作者： Felipe MONTALVA Hector PAVES Diego PEREZ-VENEGAS Karin G BARRIENTOS E Carola VALENCIA Diego MIRANDA-URBINA Mauricio SEGUEL facultad de Ciencias Biologicas Pontificia Universidad Catolica de ChileSantiagoChile departamento de Ciencias Basicas Facultad de CienciasUniversidad Santo TomasOsornoChile Centro de Investigacion y Gestion de Recursos Naturales(CIGREN) Instituto de BiologıaFacultad de CienciasUniversidad de ValparaısoValparaısoChile Programa de Doctorado en Ciencias Agrarias Escuela de Graduados de laFacultad de Ciencias Agrarias y AlimentariasUniversidad Austral de ChileValdiviaChile facultad de Medicina Veterinaria Sede PatagoniaUniversidad San SebastianPuerto MonttChile Instituto de Ciencias Biologicas Universidad de TalcaTalcaChile department of Pathobiology Ontario Veterinary CollegeUniversity of GuelphGuelphCanada

Interspecific interactions are key drivers of individual and population-level fitness in a wide range of ***,in marine ecosystems,it is relatively unknown which biotic and abiotic factors impact behavioral interactions between competing *** assessed the impact of weather,marine productivity,and population structure on the behavioral agonistic interactions between South American fur seals(SAFSs),Arctocephalus australis,and South American sea lions(SASLs),Otaria byronia,in a breeding colony of *** hypothesized that agonistic interactions between SAFSs and SASLs respond to biotic and abiotic factors such as SAFS population structure,marine productivity,and *** found that SASL and SAFS interactions almost always resulted in negative impacts on the social structure or reproductive success of the SAFS *** adult males initiated stampedes of SAFS and/or abducted and predated SAFS *** SAFS males abundance and severe weather events were negatively correlated with agonistic interactions between ***,proxies for lower marine productivity such as higher sea surface temperature and lower catches of demerso-pelagic fish were the most important predictors of more frequent agonistic interactions between SAFS and *** the current scenario of decline in marine biomass due to global climate change and overfishing,agonistic interactions between competing marine predators could increase and exacerbate the negative impacts of environmental change in these species.

关键词： interspecific interactions climate change Guafo Island sea surface temperature South American fur seal South American sea lion

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Ligand effects on the structure and vibrational properties of the thiolated Au18 cluster

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Progress in Natural Science:Materials International 2016年第5期26卷 510-515页

作者： Alfredo Tlahuice-Flores CICFIM-facultad de Ciencias Físico-Matemáticas Universidad Autónoma de Nuevo León

Most of the studies devoted to thiolated gold clusters suppose that their core and Au-S framework do not suffer from distortion independently of the protecting ligands（-SR） and it is assumed as correct to simplify the ligand as SCH3. In this work is delivered a systematic study of the structure and vibrational properties（IR and Raman）of the Au18（SR）14cluster. The pursued goal is to understand the dependency of the displayed vibrational properties of the thiolated Au18cluster with the ligands type. A set of six ligands was considered during calculations of the vibrational properties based on density functional theory（DFT） and in its dispersioncorrected approach（DFT-D）.

关键词： Gold cluster Ligand effects Structure Vibration Au18(SR)14 density functional theory

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Tailored optical propulsion forces for controlled transport of resonant gold nanoparticles and associated thermal convective fluid flows

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Light(Science & Applications) 2020年第1期9卷 256-266页

作者： Jose A.Rodrigo Mercedes Angulo Tatiana Alieva facultad de Ciencias fisicas Ciudad Universitaria s/nUniversidad Complutense de Madrid28040 MadridSpain

Noble metal nanoparticles illuminated at their plasmonic resonance wavelength turn into heat *** phenomenon has prompted the development of numerous applications in science and *** optical manipulation of such resonant nanoparticles could certainly extend the functionality and potential applications of optothermal *** this article,we experimentally demonstrate optical transport of single and multiple resonant nanoparticles(colloidal gold spheres of radius 200 nm)directed by tailored transverse phase-gradient forces propelling them around a 2D optical *** show how the phase-gradient force can be designed to efficiently change the speed of the *** have found that multiple hot nanoparticles assemble in the form of a quasi-stable group whose motion around the laser trap is also controlled by such optical propulsion *** assembly experiences a significant increase in the local temperature,which creates an optothermal convective fluid flow dragging tracer particles into the ***,the created assembly is a moving heat source controlled by the propulsion force,enabling indirect control of fluid flows as a micro-optofluidic *** existence of these flows,probably caused by the temperature-induced Marangoni effect at the liquid water/superheated water interface,is confirmed by tracking free tracer particles migrating towards the *** propose a straightforward method to control the assembly size,and therefore its temperature,by using a nonuniform optical propelling force that induces the splitting or merging of the group of *** envision further development of microscale optofluidic tools based on these achievements.

关键词： thermal fluid transport

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Inference for a truncated positive normal distribution

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 163-176页

作者： Hector J.Gomez Neveka M.Olmos Hector Varela Heleno Bolfarine departamento de Ciencias Matematicas y Ffsicas Facultad de IngenierlaUniversidad Catolica de TemucoTemucoChile departamento de Matematicas Facultad de Ciencias BasicasUniversidad de AntofagastaAntofagastaChile departamento de Estatfstica IMEUniversidade de Sao PauloSao PauloBrazil

The main object of this paper is to study an extension of the half normal distribution defined by adding a positive truncation to it. The new model is more flexible than the half-normal distribution and contains the half normal distribution as a special case. Properties of this distribution, such as moments, hazard function and entropy are studied and parameters estimation is dealt with by using inoinents and inaxiinuin likelihood. A real data application indicates good fit performance of the new model when compared to other competitors in litera- tures.

关键词： half-normal distribution maximum likelihood truncation

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Ontogenetic transition in leaf traits: a new cost associated with the increase in leaf longevity

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Journal of Plant Ecology 2014年第6期7卷 567-575页

作者： Sonia Mediavilla Maria Herranz Patricia González-Zurdo Alfonso Escudero departamento de Ecología Facultad de BiologíaUniversidad de SalamancaSalamanca 37071Spain

Aims Recent work has identified a worldwide‘economics’spectrum of correlated leaf traits that mainly reflects the compromises between maximizing leaf longevity and short-term ***,during the early stages of tree growth different species tend to exhibit a common strategy,because competition for soil water and nutrients forces the maximization of short-term productivity owing to the need for rapid growth during the most vulnerable part of the tree’s life ***,our aim here was to compare the variations that occur during ontogeny in the different leaf traits(morphology and leaf chemical composition)of several coexisting Mediterranean woody species differing in their leaf life spans and to test our hypothesis that tree species with a long leaf life span should exhibit larger shifts in leaf characteristics along *** Six Mediterranean tree species differing in leaf life span,selected from three plots located in central-western Spain,were studied during three growth stages:seedlings,juveniles and mature *** life span,leaf morphology(leaf area,dry weight,thickness and mass per unit area)and chemical composition(N and fibre con-centrations)were measured in all six *** magnitude of the ontogenetic changes in the different traits was estimated and related to the mean leaf longevity of the different *** Findings Along ontogeny,strong changes were observed in all variables *** early growth stages showed lower leaf thickness,leaf thickness and mass per unit area and N,cellulose and hemi-cellulose concentrations than mature trees,but a higher lignin ***,these changes were especially marked in species with a longer leaf life span at *** dif-ferences in leaf life span,leaf morphology and chemical com-position were stronger at the mature stage than at the seedling *** conclude that greater plasticity and more intense strat-egy shifts along ontogeny are necessarily associ

关键词： leaf morphology leaf N concentration fibre content Pinus Quercus tree age class

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