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Seed loss before seed predation: experimental evidence of the negative effects of leaf feeding insects on acorn production

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Integrative Zoology 2018年第3期13卷 238-250页

作者： Tara CANELO Álvaro GAYTÁN Guillermo GONZÁLEZ-BORNAY raul BONAL Forest Research Group INDEHESAUniversity of ExtremaduraPlasenciaSpain DITEG Research Group University of Castilla-La ManchaToledoSpain CREAF Cerdanyola del VallèsCataloniaSpain

Insect herbivory decreases plant fitness by constraining plant growth,survival and reproductive *** studies on the effects of herbivory in trees rely on correlational inter-individual comparisons and could,thus,be affected by confounding factors linked to both herbivory and plant *** the Mediterranean Holm oak(Quercus ilex)as a study model,we followed an experimental approach in which leaf-feeding insects(mainly Lepidoptera caterpillars)were excluded from some shoots in all study *** subjected to herbivore exclusion exhibited lower defoliation rates and produced more acorns than control *** constrained shoot growth throughout the study period,but had no effect on the number of female flowers produced per *** production was,however,lower in control shoots due to their higher abortion rates,and also to their greater mortality risk during summer drought,as shoots with fewer leaves were less likely to *** reaction to herbivory inhibits certain physiological pathways involved in plant growth,which,together with the effects of physical damage,reduces the amount and efficiency of the photosynthetic *** increases their vulnerability to environmental stresses,such as water deficit,which limit resource *** is likely a key factor affecting oak regeneration,as it may be a significant source of seed loss prior to pre-dispersal acorn *** experimental studies could help to elucidate its effects in contrasting *** Mediterranean regions,the harsher droughts predicted by climate change models could worsen the effects of insect herbivory on oak reproductive output.

关键词： drought stress insect defoliation oak seed abortion shoot mortality

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New Results on Truncated Elliptical Distributions

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Communications in Mathematics and Statistics 2021年第3期9卷 299-313页

作者： raul Alejandro Moran-Vasquez Silvia L.P.Ferrari Institute of Mathematics University of AntioquiaCalle 67 No.53-108MedellínColombia Department of Statistics University of Sao PauloRua do Matão 1010São Paulo 05508-090Brazil

Truncated elliptical distributions occur naturally in theoretical and applied statistics and are essential for the study of other classes of multivariate *** members of this class are the multivariate truncated normal and multivariate truncated t *** derive statistical properties of the truncated elliptical *** of our results establish new properties of the multivariate truncated slash and multivariate truncated power exponential distributions.

关键词： Elliptical distribution Log-concavity Multivariate power exponential distribution Multivariate slash distribution Truncated distribution

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Female competition for availability of males in insects:the Nezara viridula(Linnaeus,1758)model

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Insect Science 2020年第4期27卷 801-814页

作者： Andrej Cokl Alenka Zunic Kosi raul Alberto Laumann Meta Virant-Doberlet Department of Organisms and Ecosystems Research National Institute of BiologyLjubljanaSI-1000Slovenia Semiochemicals Laboratory Embrapa Genetic Resources and BiotechnologyBrasiliaDF 71070Brazil

Multimodal communication in solitary stinkbugs enables them to meet,mate and *** plant-dwelling species exchange information during the calling phase of mating behavior using substrate-borne vibratory signals.A female-biased gender ratio induces rivalry and competition for a sexual *** competition for males,first described among Heteroptera in three stinkbug species,revealed species specific differences and opened the question of plasticity in individually emitted temporal and frequency signal characteristics during calling and rival *** address this question and gain an insight into the mechanisms underlying stinkbug female rivalry,we compared the characteristics of alternated signals in the southern green stinkbug Nezara viridula(Linnaeus,1758)(Hemiptera:Pentatomidae).Compared to male rivalry,female rivalry is more complex,lasts longer and runs through successive phases by a combination of different song *** male pheromone triggers alternation between females,producing song pulses that occasionally overlap each *** female initiates the rivalry by changing individual pulses into pulse trains of three different *** competing female alternates with pulses of changed temporal characteristics at lower levels of rivalry and by varying the frequency characteristics of pulse trains at higher *** female rivalry,the male either stops responding or occasionally emits calling and courtship signals in response to the female that has produced signals of steady temporal *** rivalry shows complex and species specific patterns of information exchange at different levels with a broad-range variation of temporal and frequency characteristics of,until now,unidentified vibratory emissions.

关键词： biotremology female social conflict Nezara viridula rivalry signal discrimination

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Tree ecophysiology in the context of climate change

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Journal of Forestry Research 2023年第1期34卷 1-5页

作者： Yanbo Hu raul Antonio Sperotto Georgios Koubouris Srđan Stojnić Nacer Bellaloui Northeast Forestry University Harbin 150040People’s Republic of China Graduate Program in Biotechnology Life Sciences AreaUniversity of Taquari Valley-UnivatesLajeadoBrazil Graduate Program in Plant Physiology Federal University of PelotasPelotasBrazil Laboratory of Olive Cultivation Institute of Olive TreeSubtropical Crops and ViticultureHellenic Agricultural Organization DIMITRALeoforos Karamanli 16773134 ChaniaCreteGreece Institute of Lowland Forestry and Environment University of Novi SadAntonaČehova 13dNovi SadSerbia Crop Genetics Research Unit Agricultural Research ServiceUSDA141 Experiment Station RoadStonevilleMS 38776USA

Forest structure and function strongly depend on and concurrently influence environmental *** performance is generally governed by its genetics and environment;thus,recent hotspots in this field include tree genotype×environment,phenotype×environment,and functional trait×environment *** editorial,review,and 22 original research articles in this Special Issue,"Tree ecophysiology in the context of climate change",highlight ecophysiological phenomena(e.g.,climate hormesis,seed germination,tree mortality),processes(e.g.,tree metabolism,photosynthate allocation,nutrient uptake and transport),indicators(e.g.,carbon sequestration,pollutants),measurements(e.g.,thermal time methods,soil quality indices,vegetation spectral index,and near-infrared leaf reflectance),and modeling(e.g.,climate correlations with tree growth,photo synthetic phenology,hydraulic strategies,OliveCan model)in the context of global climate *** forest-environment interactions from an ecophysiological perspective as climate changes provides insights into species fitness in suboptimal environments,species competition for limited resources,and phylogenetic divergence or convergence of species,and predicting species distributions.

关键词： Tree ecophysiology Climate change Climate hormesis Phenology Thermostability Forest resilience Hydraulics

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As-cast and extruded Mg-Zn-Ca systems for biodegradable implants:Characterization and corrosion behavior

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Journal of Magnesium and Alloys 2023年第3期11卷 1102-1120页

作者： Lara Moreno Endzhe Matykina Kiryl A.Yasakau Carsten Blawert raul Arrabal Marta Mohedano Departamento de Ingeniería Química y de Materiales Facultad de Ciencias QuímicasUniversidad Complutense de Madrid28040 MadridSpain Department of Materials and Ceramic Engineering CICECO-Aveiro institute of materialsUniversity of Aveiro3810-193 AveiroPortugal Institute of Surface Science Helmholtz-Zentrum HereonMax-Planck Strasse 1Geesthacht 21502Germany

The aim of the present study is to evaluate the effect of alloy processing and composition as well as the pH control and testing medium on the in vitro corrosion performance of Mg-Zn-Ca systems for biodegradable *** grain size and secondary phases were analyzed by optical microscopy,scanning electron microscopy,transmission electron microscopy,and X-ray *** kelvin probe force microscopy(SKPFM)was used to analyze the Volta potential values of the second *** corrosion performance of the three alloys was evaluated by electrochemical and hydrogen evolution methods inα-MEM with and without organic species(*** and inorganicα-MEM).Two strategies were followed to evaluate the influence of the pH on the corrosion behavior:daily solution replacement and CO_(2)flow based pH *** all the materials,the organic medium accelerates the corrosion *** pH maintained by CO_(2)flow through the medium results in considerably higher corrosion rates for all *** impact of pH is lesser on the as-cast alloys due to the barrier effect of the secondary phases,particularly pronounced in the Mg1Zn1Ca alloy which showed the lowest corrosion *** wrought Mg0.5Zn0.2Ca alloy that lacks the refined secondary phase network and exhibits high number of twins undergoes accelerated uniform corrosion under constant pH conditions.

关键词： MgZnCa Magnesium Biomaterials Characterization Corrosion

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Catalysts for the hydrogen evolution reaction in alkaline medium:Configuring a cooperative mechanism at the Ag-Ag_(2)S-MoS_(2) interface

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Journal of Energy Chemistry 2022年第11期31卷 481-488,I0013页

作者： Avraham Bar-Hen Simon Hettler Ashwin Ramasubramaniam raul Arenal Ronen Bar-Ziv Maya Bar Sadan Department of Chemistry Ben-Gurion University of the NegevBeer-Sheva 8410501Israel Department of Chemistry Nuclear Research Center NegevP.O.Box 9001Beer-Sheva 84190Israel Laboratorio de Microscopías Avanzadas Universidad de Zaragoza50018 ZaragozaSpain Instituto de Nanociencia y Materiales de Aragon CSIC-U.de ZaragozaCalle Pedro Cerbuna 1250009 ZaragozaSpain Department of Mechanical and Industrial Engineering University of MassachusettsAmherstMA 01003United States ARAID Foundation 50018 ZaragozaSpain

Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen *** this end,delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and,specifically,making use of hybrid structures,can produce synergistic effects that lead to highly active ***,we present a core-shell catalyst of Ag@MoS_(2)that shows promising results towards the hydrogen evolution reaction(HER)in both 0.5 M H_(2)SO_(4)and 0.5 M *** this hybrid structure,the MoS_(2)shell is strained and defective,and charge transfer occurs between the conductive core and the shell,contributing to the electrocatalytic *** shelling process results in a large fraction of Ag_(2)S in the cores,and adjusting the relative fractions of Ag,Ag_(2)S,and MoS_(2)leads to improved catalytic activity and fast charge-transfer *** suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces,where the Ag(Ⅰ)sites in Ag_(2)S drive the water dissociation step,and the formed hydrogen subsequently recombines on the defective MoS_(2)*** study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS_(2)for HER in alkaline conditions.

关键词： Water splitting Core-shell Catalytic mechanism Electrocatalysis 2D materials

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Simplification workflow for hydraulically fractured reservoirs

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Petroleum 2018年第2期4卷 134-147页

作者： raul Velasco Palash Panja Milind Deo Energy&Geoscience Institute Salt Lake CityUSA Department of Chemical Engineering The University of UtahSalt Lake CityUSA

Production from unconventional formations,such as shales,has significantly increased in recent years by stimulating large portions of a reservoir through the application of horizontal drilling and hydraulic *** oil shales are heavily dependent on oil prices,production forecasts remain positive in the North-American *** to the complexity of hydraulically fractured tight formations,reservoir numerical simulation has become the standard tool to assess and predict production performance from these unconventional *** of these unconventional fields are immense,consisting of multistage and multiwell projects,which results in impractical simulation run ***,simplification of large-scale simulation models is now common both in the industry and *** simplified models such as the“single fracture”approach do not often capture the physics of large-scale projects which results in inaccurate *** this paper we present a simple,yet rigorous workflow that generates simplified representative models in order to achieve low simulation run times while capturing physical phenomena which is fundamental for accurate *** proposed workflow is based on consideration of representative portions of a large-scale model followed by postprocess scaling to obtain desired full model *** simplified models that result from the application of the proposed workflow for a single well and a multiwell case are compared to full-scale models and the“single fracture”*** of fluid rates and cumulative production show that accurate results are possible for simplified models if all important components for a particular case are taken into ***,application of the workflow is shown for a heterogeneous field case where prediction studies can be carried out.

关键词： Hydraulic fracture Shale Simulation workflow Multiwell Field case

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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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Body Composition,Aerobic Fitness,Isokinetic Profile,and Vertical Jump Ability in Elite Male and Female Volleyball and Beach Volleyball Players

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Journal of Science in Sport and Exercise 2023年第4期5卷 385-395页

作者： raul Freire Matheus Hausen Glauber Pereira Alex Itaborahy Olympic Laboratory Brazil Olympic CommitteeRio de JaneiroBrazil Laboratory of Biomechanics and Motor Behavior Institute of Physical Education and SportsRio de Janeiro State UniversityRio de JaneiroBrazil

Purpose This study aimed to compare the physical attributes of male and female Volleyball and Beach Volleyball *** Fifty-five athletes from Volleyball(Male,n=19,age 27.3±6.1 years,body mass 93.2±9.9 kg,and height 196.8±7.4 cm and Female,n=16,age 28.0±5.6 years,body mass 76.9±8.8 kg,and height 179.9±5.8 cm)and Beach Volleyball(Male,n=10,age 26.8±3.4 years,body mass 92.9±9.9 kg,and height 195.3±7.9 cm and Female,n=10,age 31.1±6.2 years,body mass 74.6±8.5 kg,and height 180.9±6.0 cm)participated in the *** tests were performed in a single visit to the laboratory in the following order:body composition,vertical jump(squat and countermovement jump),isokinetic(knees and shoulders),and cardiopulmonary exercise *** variables were analyzed using a two-way ANOVA(Sex and Sport factors)for independent *** Beach Volleyball athletes presented lower body fat(P=0.03;ES=0.32)and higher maximal cardiorespiratory variables(VO2,HR,and vVO2max).Only flexion bilateral difference(knee)at 60°/s was affected by sex(P=0.002;ES=0.63).For shoulders,only dominant external/internal rotation ratio presented a significant interaction for sport and sex(P=0.05;ES=0.28).Regarding vertical jumps,Volleyball male players presented a greater elastic index than BV male players(P=0.002,ES=0.67).Conclusion Beach Volleyball players are thinner and have better cardiorespiratory fitness than Volleyball ***,they presented less use of elastic properties for vertical jumping and have a greater muscle imbalance in the hamstrings than Volleyball players.

关键词： Athlete profile Court VO2max Neuromuscular Sex Sport

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Photometric and Spectroscopic Studies for Two Magnetic-activity Contact Binaries:V724 And and QR Com

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Research in Astronomy and Astrophysics 2022年第11期22卷 51-60页

作者： Shuang Wang raul Meichel Huiyu Yuan Yuangui Yang School of Physics and Electronic Information Huaibei Normal UniversityHuaibei City 235000China Observatorio Astronomico Nacional Instituto de AstronomiaUniversidad Nacional Autonoma de MexicoApartado Postal 877EnsenadaB.C.22830Mexico

We presented new CCD photometry for two contact binaries,V724 And and QR Com,which were observed during the 2020–2022 observing *** using the Wilson–Devinney method,the photometric solutions were deduced from new observed data and TESS *** asymmetric light curves were modeled by a dark spot on the more massive *** indicate that the starspot may immigrate or disappear on the surface of the active *** the TESS observations of QR Com,it is discovered that the difference between light maxima exhibits a 29.5 day oscillation,which implies the continuous evolution of spot feathers on the timescale of several *** mass ratio and fill-out factor are q=2.308 and f=11.55% for V724 And,and q=0.624 and f=12.77% for QR Com,*** the(O-C)curve,the orbital period secularly decrease at a rate of d P/dt=-1.66×10^(-7)day yr^(-1)for V724 And and d P/dt=-3.98×10^(-7)day yr^(-1)for QR Com,which was interpreted by mass transfer from the more massive component to the less massive *** period decreasing,this kind of shallow-contact binaries,V724 And and QR Com,will evolve into the deep-contact configurations.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters stars:low-mass

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