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Differential responses to artificial selection on oviposition site preferences in drosophila melanogaster and D. simulans

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Insect Science 2015年第6期22卷 821-828页

作者： Eduardo M. Soto Maria I. L. Betti Juan Hurtado esteban Hasson Departamento de Ecologia Genetica y Evolucion IEGEBA (CONICET-UBA) Facultad de Ciencias Exactas y Naturales Universidad deBuenos Aires Buenos Aires Argentina

The preference-performance relationship in plant-insect interactions is a cen- tral theme in evolutionary ecology. Among many insects, eggs are vulnerable and larvae have limited mobility, making the choice of an appropriate oviposition site one of the most important decisions for a female. We investigated the evolution of oviposition preferences in drosophila melanogaster Meigen and drosophila simulans Sturtevant by artificially selecting for the preference for 2 natural resources, grape and quince. The main finding of our study is the differential responses of D. melanogaster and D. simulans. Although preferences evolved in the experimental populations of D. melanogaster, responses were not consistent with the selection regimes applied. In contrast, responses in D. simulans were consistent with expectations, demonstrating that this species has selectable genetic variation for the trait. Furthermore, crosses between D. simulans divergent lines showed that the genetic factors involved in grape preference appear to be largely recessive. In summary, our artificial selection study suggests that D. melanogaster and D. simulans possess different genetic architectures for this trait.

关键词： artificial selection behavior drosophila genetic variation naturalresources oviposition preference

Quality indicators in subtropical soils of Formosa,Argentina:Changes for agriculturization process

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International Soil and Water Conservation research 2014年第4期2卷 13-24页

作者： Juan esteban Baridón roberto raúl Casas Universidad Nacional de La Plata Buenos AiresArgentina Laboratorio de Suelos Aguas y Forrajes.Centro de Validación de Tecnologías Agropecuarias IbarretaIbarreta(CP 3624)FormosaArgentina Centro de Investigación de recursos Naturales.Instituto Nacional de Tecnología Agropecuaria:dr.Nicolás repetto(ex Las Cabañas)y Los reseros Castelar(CP1712)Buenos AiresArgentina

The agriculturization process has been defined as the advance of annual crops in different environments,in competition with traditional land uses such as agriculture rotations with *** Argentina and other countries agriculturization has different degrees of impact on natural *** the northeast region of the province of Formosa,Argentina,agriculturization includes deforestation(clear cutting,slash burning and plowing),technological improvements and changes in land *** of these alterations,it is necessary to define the state of the soil to evaluate its *** can be done by means of indicators,which are not universal;they differ according to the use,management and type of soils,weather conditions and *** objectives of this paper are:(1)To identify quality indicators for subtropical Argiudolls and Hapludolls;(2)To determine which indicators related to organic matter are most affected during *** changes produced in the Typic Hapludolls and Typic Argiudolls after 25 years of continuously using native forests,agriculture,fruit plantations and pastures were *** changes were in pH,electrical conductivity,total organic carbon,particulate organic carbon,total nitrogen,structural stability,hydraulic conductivity,respiration and dehydrogenase and urease and enzyme *** with significant differences between diverse uses were evaluated by multivariate methods,Principal Component Analysis,and Correlation *** results of this study showed that total organic carbon,particulate organic carbon,structural stability and dehydrogenase activity are the quality indicators most affected by *** are related to organic matter.

关键词： Hapludolls Argiudolls Soil quality Soil use

Effect of Organo-Modified Nanosepiolite on Fire Behaviors and Mechanical Performance of Polypropylene Composites

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中国化学:英文版 2015年第2期33卷 285-291页

作者： Junhao Zhang Sergio de Juan Antonio esteban-Cubillo Julio Santarén De-Yi Wang Madrid Institute for Advanced Studies of Materials(IMDEA-Materials) C/Eric Kandel2Getafe(Madrid)28906Spain Tolsa S.A.r.&D.Department Carretera de Madrid a Rivas Jarama3528031 MadridSpain

The objective of the study was to investigate the effect of the organo-modified nanosepiolite(ONSep)on improving the fire safety of polypropylene(PP).The composites based on PP,flame retardant master batch(MB-Fr,25 wt%PP+50 wt%decabromodiphenyl ether(DBDPE)+25%antimony trioxide(ATO))and ONSep were prepared via melt *** results of the limiting oxygen index(LOI)and vertical burning rating(UL-94)test indicated that PP/40 wt%MB composites had no rating with seriously dripping phenomenon,while the LOI value was only ***,as 4 wt%ONSep was added in PP/40 wt%MB composites,the composites achieved UL94 V-0 rating and the LOI value was *** comparison,PP/50 wt%MB composites could not reach the V-0 rating *** TGA results revealed that the addition of ONSep enhanced the thermal stability of the PP/MB-Fr *** cone calorimeter results indicated that the heat release rate,average mass loss rate,smoke production rate and smoke temperature of the PP/40 wt%MB-Fr/4 wt%ONSep composites decreased in comparison with those of PP/40 wt%MB-Fr ***,the Young modulus and impact strength were also much better improved with the increase of ONSep ***,the synergistic flame retardancy of ONSep in PP/MB-Fr matrix significantly containing a halogen based flame retardant(DBDPE)significantly improved the fire safety and mechanical properties of the composites,and allowed to decrease the total amount of brominated fire retardants.

关键词： nanosepiolite polypropylene flame retardancy heat release rate

Surface topography and free energy regulate osteogenesis of stem cells: effects of shape-controlled gold nanoparticles

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Biomaterials Translational 2021年第2期2卷 165-173页

作者： Kamolrat Metavarayuth esteban Villarreal Hui Wang Qian Wang Department of Chemistry and Biochemistry University of South CarolinaColumbiaSCUSA

The surface free energy of a biomaterial plays an important role in the early stages of cell-biomaterial interactions,profoundly influencing protein adsorption,interfacial water accessibility,and cell attachment on the biomaterial *** multiple approaches have been developed to engineer the surface free energy of biomaterials,systematically tuning their surface free energy without altering other physicochemical properties remains *** this study,we constructed an array of chemically-equivalent surfaces with comparable apparent roughness through assembly of gold nanoparticles adopting various geometrically-distinct shapes but all capped with the same surface ligand,(1-hexadecyl)trimethylammonium chloride,on cell culture *** found that bone marrow stem cells exhibited distinct osteogenic differentiation behaviours when interacting with different types of substrates comprising shape-controlled gold *** results reveal that bone marrow stem cells are capable of sensing differences in the nanoscale topographical features,which underscores the role of the surface free energy of nanostructured biomaterials in regulating cell *** study was approved by Institutional Animal Care and Use Committee,School of Medicine,University of South Carolina.

关键词： biomaterials gold nanoparticles osteogenesis stem cells surface free energy

drug repurposing for COVID-19 using machine learning and mechanistic models of signal transduction circuits related to SArS-CoV-2 infection

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Signal Transduction and Targeted Therapy 2021年第1期6卷 11-13页

作者： Carlos Loucera Marina esteban-Medina Kinza rian Matias MFalco Joaquin Dopazo Maria Pena-Chilet Clinical Bioinformatics Area.Fundacion Progreso y Salud(FPS).CDCA Hospital Virgen del Rocio41013 SevillaSpain Computational Systems Medicine Institute of Biomedicine of Seville(IBIS)Hospital Virgen del Rocio41013 SevillaSpain Bioinformatics in rare Diseases(BiEr).Centro de Investigacion Biomedica en red de Enfermedades raras(CIBErEr) FPSHospital Virgen del Rocio41013 SevillaSpain FPS/ELIXIr-es Hospital Virgen del RocioSevilla 42013Spain

Dear Editor,drug repurposing is a convenient alternative when the need for new drugs in an unexpected medical scenario is urgent,as is the case of emerging *** recent years,approaches based on network biology have demonstrated to be superior to genecentric ones.1 Here,we use an innovative methodology that combines mechanistic modeling of the signal transduction circuits related to SArS-CoV-2 infection(the COVID-19 disease map)with a machine-learning algorithm that learns potential causal interactions between proteins,already targets of drugs,and specific signaling circuits in the COVID-19 disease map,to suggest potentially repurposable drugs.

关键词： signal network drugs

drag reduction via turbulent boundary layer flow control

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Science China(Technological Sciences) 2017年第9期60卷 1281-1290页

作者： ABBAS Adel BUGEDA Gabriel FErrEr esteban FU Song PErIAUX Jacques PONS-PrATS Jordi VALErO Eusebio ZHENG Yao School of Aeronautics Escuela Tecnica Superior de lngenierla Aeronautica y del Espacio de la Universidad Politecnica de Madrid (ETS1.4E-UPM) Universidad Politecnica de Madrid Pza. Cardenal Cisneros 3 Madrid E-28040 Spain International Center for Numerical Methods in Engineering (CIMNE) Gran Capita s/n Campus Nord UPC Barcelona 08034 Spain Civil and Environmental Department Universitat Politecnica de Catalunya. BarcelonaTech Gran Capita s/n Campus Nord UPC Barcelona 08034 Spain Centre for Computational Simulation-UPM Scientific and Technological Park (Campus Montegancedo) 28223 Pozuelo de Alarcon Spain School of Aerospace Engineering Tsinghua University Beijing 100084 China School of Aeronautics andAstronautics Zhejiang University Hangzhou 310027 China

Turbulent boundary layer control(TBLC) for skin-friction drag reduction is a relatively new technology made possible through the advances in computational-simulation capabilities,which have improved the understanding of the flow structures of *** in micro-electronic technology have enabled the fabrication of active device systems able to manipulating these *** combination of simulation,understanding and micro-actuation technologies offers new opportunities to significantly decrease drag,and by doing so,to increase fuel efficiency of future *** literature review that follows shows that the application of active control turbulent skin-friction drag reduction is considered of prime importance by industry,even though it is still at a low technology readiness level(TrL).This review presents the state of the art of different technologies oriented to the active and passive control for turbulent skin-friction drag reduction and contributes to the improvement of these technologies.

关键词： turbulent boundary layer flow control drag reduction skin-friction drag reduction

Exploring the factors influencing the hydrological response of soil after low and high-severity fires with post-fire mulching in Mediterranean forests

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International Soil and Water Conservation research 2023年第1期11卷 169-182页

作者： Manuel esteban Lucas-Borja Pedro Antonio Plaza-Alvarez Xiangzhou Xu Bruno Gianmarco Carra Demetrio Antonio Zema Castlla La Mancha University School of Advanced Agricultural and Forestry Engineering.Department of Agroforestry Technology and Science and GeneticsCampus Universitario s/nE-02071AlbaceteSpain "Mediterranea"University of reggio Calabria Department"AGRARIA"Localita Feo di VitoI-89122Reggio CalabriaItaly Institute of Environmental and Water resources School of Hydraulic EngineeringDalian University of Technology2Ling GongGanjingziDalian116024China

Despite ample literature,the influence of the individual soil properties and covers on the hydrological response of burned soils of forests has not clearly identified.A clear understanding of the surface runoff and erosion rates altered by wildfires and prescribed fires is beneficial to identify the most suitable post-fire treatment This study has carried out a combined analysis of the hydrological response of soil and its driving factors in burned forests of Central-Eastern *** pine stands of these forests were subjected to both prescribed fire and wildfire,and,in the latter case,to post-fire treatment with ***,simple multi-regression models are proposed to predict runoff and erosion in the experi-mental *** the case of the prescribed burning,the fire had a limited impact on runoff and erosion compared to the unburned areas,due to the limited changes in soil *** contrast,the wildfire increased many-fold the runoff and erosion rates,but the mulching reduced the hydrological response of the burned soils,particularly for the first two-three rainfalls after the *** increase in runoff and erosion after the wildfire was associated to the removal of the vegetation cover,soil water repellency,and ash left by fire;the changes in water infiltration played a minor role on runoff and *** multi-regression models developed for the prescribed fire were accurate to predict the post-fire runoff ***,these models were less reliable for predictions of the mean erosion *** predictions of erosion after wildfire and mulching were excellent,while those of runoff were not satisfactory(except for the mean values).These results are useful to better understand the relations among the hydrological effects of fire on one side and the main soil properties and covers on the other ***,the proposed prediction models are useful to support the planning activities of forest managers and hydrologists towards a more ef

关键词： Wildhre Prescribed fire Soil cover Soil properties Soil water repellency Infiltration rate Surface runoff Soil loss Erosion

Mechanical and natural ventilation systems in a greenhouse designed using computational fluid dynamics

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 1-16页

作者： Jorge Flores-Velazquez Juan I.Montero esteban J.Baeza Juan C.Lopez Mexican Institute of Water Technology.Paseo Cuauhnáhuac 8532 Col.ProgresoC.P.62550JiutepecMor.Mexico Institut de recerca i Tecnologia Agroalimentàries 08348Cabrils(Barcelona)Spain IFAPA Centro La Mojonera(Junta de Andalucía) Camino San Nicolás 104745 La MojoneraAlmeríaSpain Fundación Cajamar.Estación Experimental“Las Palmerillas”Autovía del Mediterráneo Km 416 704710El EjidoAlmeríaSpain

The aim of this study was to analyse air exchange and temperature distribution in a greenhouse with combined mechanical and natural ventilation and to design more efficient mechanical ventilation *** this purpose,a computational fluid dynamics(CFD)model of the greenhouse was *** configurations were considered:Configuration 1(mechanical ventilation and closed roof ventilators),Configurations 2 and 3(mechanical ventilation and roof ventilators open 30%and 100%,respectively).After validation,the CFD model was used to improve the design of the greenhouse mechanical ventilation system in each of the three configurations *** greenhouse lengths,28 m,50 m,75 m and 100 m,were used in the *** to fan ventilation only,roof ventilation improved the climate of fan-ventilated greenhouses in terms of the air exchange rate(22%)and climate uniformity because the internal air was mixed better than with mechanical ventilation *** the greenhouse length increased,more advantages were achieved with natural ventilation compared to mechanical *** most configurations,there was a strong linear correlation between temperature gradient and greenhouse *** greenhouse whose regression line had the steepest slope was the one with closed roof *** the fan capacity produced a general reduction in temperature,but the effect was less intense for the greenhouses with open roof *** to box inlet ventilators,an enlarged continuous inlet in the wall opposite the fans increased overall system performance because it eliminated backflow recirculation zones,which are prone to produce high temperatures.

关键词： greenhouse cooling fan ventilation roof ventilators combined ventilation

Symptomatic accommodative and binocular dysfunctions from the use of flat-panel displays

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 501-505页

作者： esteban Porcar Juan Carlos Montalt Alvaro M. Pons Enrique Espana-Gregor Department of Optics Optometry and Vision Sciences Physics College University of Valencia Burjassot (Valencia) 46100 Spain Department of Surgery Ophthalmology Unit Faculty of Medicine and Odontology la Fe University and Polytechnic Hospital Valencia 46026 Spain

AIM： To determine the presence of symptomatic accommodative and non-strabismic binocular dysfunctions （***） in a non-presbyopic population of video display unit （VDU） users with flat-panel displays. METHODS： One hundred and one VDU users, aged between 20 to 34y, initially participated in the study. This study excluded contact-lens wearers and subjects who had undergone refractive surgery or had any systemic or ocular disease. First, subjects were asked about the type and nature of eye symptoms they experienced during VDU use. Then, a thorough eye examination excluded those subjects with a significant uncorrected refractive error or other problem, such as ocular motility disorders, vertical deviation, strabismus and eye diseases. Finally, the remaining participants underwent an exhaustive assessment of their accommodative and binocular vision status. rESULTS： Eighty-nine VDU users （46 females and 43 males） were included in this study. They used flat-panel displays for an average of 5±1.9h a day. Twenty subjects presented *** （22.5%）. Convergence excess was the most frequent non-strabismic binocular dysfunction （9 subjects）, followed by fusional vergence dysfunction （3 subjects） and convergence insufficiency （2 subjects）. Within the accommodative dysfunctions, accommodative excess was the most common （4 subjects）, followed by accommodative insufficiency （2 subjects）. Moderate to severe eye symptoms were found in 13 subjects with ANSBD. CONCLUSION： Significant eye symptoms in VDU users with accommodative and/or non-strabismic binocular dysfunctions often occur and should not be underestimated; therefore, an appropriate evaluation of accommodative and binocular vision status is more important for this population,

关键词： general binocular dysfunctions accommodativedysfunctions non-strabismic binocular dysfunctions eyesymptoms video display unit