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The relationship between morphology and flight in Drosophila:a study of two pairs of sibling species from a natural population

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Insect Science 2024年第3期31卷 885-900页

作者： Nicolás Flaibani victoría Estefania Ortiz Juan JoséFanara valeria Paula Carreira Laboratorio de Evolucion Departamento de EcologiaGenética y Evolucion(DEGE)Facultad de Ciencias Exactas y Naturales(FCEN)Universidad de Buenos Aires(UBA)Instituto de GenéticaEcologia y Evolucion de Buenos Aires(IEGEBA)Consejo Nacional de Investigaciones Cientificasy Tecnicas(CONICET)-UBABuenos AiresArgentina

Insect flight is a complex trait involved in different behaviors,from the search for sexual partners,food,or breeding sites.Many studies have postulated the adaptive advantages of certain morphological traits in relation to increased flight capacity,such as low values of wing loading or high values of wing:thorax ratio and wing-aspect ratio.However,few studies have evaluated the relationship between variables related to flight and morphological traits in Drosophila.This work aimed to study morphological traits in males and females of two pairs of sibling species:Drosophila buzzati Patterson and Wheeler-Drosophila koeferae Fontdevila and Wasserman,and Drosophila melanogaster Meigen-Drosophila simulans Sturtevant,and to analyze its relationship with flight.We detected the highest proportion of flight time in D.koepferae and D.simulans compared to D.buzzati and D.melanogaster,respectively.Our results also revealed sexual dimorphism,with males exhibiting a higher proportion of flight time than females.Surprisingly,we did not find a general pattern to explain the relationship between morphology and the proportion of flight time because associations varied depending upon the analyses(considering all groups together or each sex-species combination separately).Moreover,these associations explained a low percentage of variation,suggesting that other nonmorphological components related to flight,such as physiological variables,should be taken into account.This work allowed us to show the variability and complexity of an aspect of flight,suggesting that the adaptive role of the morphological traits studied might have been overestimated.

关键词： morphological traits time in flight wing loading wing:thorax ratio wingaspect ratio wing second moment of area

Investigation of electrophysical, photo- and gas-sensitive properties of ZnO–SnO_(2) sol–gel fflms

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Journal of Advanced Dielectrics 2024年第1期14卷 42-50页

作者： Irina A.Gulyaeva Alexandra P.Ivanisheva Maria G.volkova victoria Yu.Storozhenko Soslan A.Khubezhov Ekaterina M.Bayan victor v.Petrov Research and Education Centre“Microsystem Technics and Multisensory Monitoring Systems”Southern Federal University Russia Department of Chemistry Southern Federal UniversityRussia Department of Physics North-Ossetian State University362025 VladikavkazRussia Department of Physics and Engineering ITMO University191002 PetersburgRussia

Thin nanocomposite fflms based on tin dioxide with a low content of zinc oxide(0.5–5 mol.%)were obtained by the sol–gel method.The synthesized fflms are 300–600 nm thick and contains pore sizes of 19–29 nm.The resulting ZnO–SnO_(2) fflms were comprehensively studied by atomic force and Kelvin probe force microscopy,X-ray diffraction,scanning electron microscopy,and high-resolution X-ray photoelectron spectroscopy spectra.The photoconductivity parameters on exposure to light with a wavelength of 470 nm were also studied.The study of the photosensitivity kinetics of ZnO–SnO_(2) fflms showed that the fflm with the Zn:Sn ratio equal to 0.5:99.5 has the minimum value of the charge carrier generation time constant.Measurements of the activation energy of the conductivity,potential barrier,and surface potential of ZnO–SnO_(2) fflms showed that these parameters have maxima at ZnO concentrations of 0.5 mol.%and 1 mol.%.Films with 1 mol.%ZnO exhibit high response values when exposed to 5–50 ppm of nitrogen dioxide at operating temperatures of 200℃ and 250℃.

关键词： Sol–gel method,ZnO–SnO_(2) films gas-sensitive properties surface potential potential barrier conduction activation energy

Coffee Leaf Rust(Hemileia vastatrix)Disease in Coffee Plants and Perspectives by the Disease Control

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 923-949页

作者： Alexis Salazar-Navarro victor Ruiz-valdiviezo Jose Joya-Dávila Daniel Gonzalez-Mendoza Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC) Nuevo LeónBaja California21705México Laboratorio de Biología Molecular del Instituto Tecnológico Nacional de Tuxtla Gutierrez(TecNM) Tuxtla GutierrezChiapas29050México Facultad de Ciencias Agronómicas Campus v.Universidad Autónoma de Chiapas(UNACH) VillafloresChiapas30470México

Coffee Leaf Rust(CLR)is caused by Hemileia vastatrix in Coffea spp.It is one of the most dangerous phytopathogens for coffee plantations in terms of coffee productivity and coffee cup quality.In this review,we resume the problem of CLR in Mexico and the pathogenesis of H.vastatrix.The review abord plant-pathogen interactions which lead a compatible or incompatible interactions and result in CLR disease or resistance,respectively.The review abord Coffea spp.defense response pathways involved in H.vastatrix pathogenicity.Additionally,current measures to control H.vastatrix proliferation and germination were aborded focused on phytosanitary actions,and biological and chemical control.Finally,new trendlines to reduce the impact of CLR as nanoparticles and nanotechnology were analyzed.

关键词： Coffee leaf rust Coffea arabica pathogenesis nanoparticles biological control

New strong bounds on sub-Gev dark matter from boosted and Migdal effects

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 48-54页

作者： victor v.Flambaum Liangliang Su Lei Wu Bin Zhu School of Physics University of New South WalesSydney 2052Australia Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China School of Physics Yantai UniversityYantai 264005China

Due to the low nuclear recoils,sub-Ge v dark matter(DM)is usually beyond the sensitivity of the conventional DM direct detection experiments.The boosted and Migdal scattering mechanisms have been proposed as two new complementary avenues to search for light DM.In this study,we consider the momentum-transfer effect in the DM-nucleus scattering to derive the new bounds on sub-Gev DM for these two scenarios.We show that such an effect is sizable so that the existing bounds on the DM-nucleus scattering cross section can be improved significantly.

关键词： sub-Gev dark matter Migdal effect atmospheric dark matter momentum-transfer

Finite Groups Isospectral to Simple Groups

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Communications in Mathematics and Statistics 2023年第2期11卷 169-194页

作者： Maria A.Grechkoseeva victor D.Mazurov Wujie Shi Andrey v.vasil’ev Nanying Yang Sobolev Institute of Mathematics Koptyuga 4NovosibirskRussia 630090 Department of Mathematics Chongqing University of Arts and SciencesChongqing 402160People’s Republic of China School of Mathematics Suzhou UniversitySuzhou 215006People’s Republic of China School of Science Hainan UniversityHaikou 570228HainanPeople’s Republic of China School of Science Jiangnan UniversityWuxi 214122People’s Republic of China

The spectrum of a finite group is the set of element orders of this group.The main goal of this paper is to survey results concerning recognition of finite simple groups by spectrum,in particular,to list all finite si... 详细信息

关键词： Finite group Simple group Element order Spectrum Recognition by spectrum

Room temperature synthesis of two-dimensional multi layer magnets based on α-Co^(Ⅱ) layered hydroxides

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Nano Materials Science 2022年第1期4卷 36-43页

作者： victor Oestreicher Christian Dolle Diego Hunt Michael Fickert Gonzalo Abellan Instituto de Ciencia Molecular(ICMol).Universidad de valencia Catedritico Jose Beltran 2PaternaValencia46980Spain Departamento de Física de la Materia Condensada GIy A.Instituto de Nanociencia y NanotecnologíaCNEA-CAC-CONICET.Av.Gral.PazSan MartinBuenas Aires1650Argentina Chair of Organic ChemistryⅡand Joint Institute of Advanced Materials and Processes(ZMP).Friedrich-Alexander-Universitát Erlangen-Nürnberg(FAU) Nikolaus-Fiebiger Strasse 1091058 Erlangen and Dr.-Mack Strasse 81Furth 90762Germany

Research on two-dimensional(2D) materials is one of the most active fields in materials science and nanotechnology. Among the members of the 2D family, layered hydroxides(LHs) represent an exceptional case of study due to their unparalleled chemical versatility which allows the modulation of their physicochemical properties at will. Nowadays, LHs based on earth-abundant metals are key materials in the areas of energy storage and conversion, hybrid materials or magnetism. α-Co hydroxides(Simonkolleite-like structures) are promising phases with tuneable electronic and magnetic properties by ligand modification. However, even in the simple case of α-Co^(Ⅱ) hydroxychlorides, the preparation of well-defined large 2D crystals is not straightforward, hindering the development of fundamental studies. Herein, we present the synthesis of 2D hexagonal crystals with outstanding sizethickness relationship(diameter > 5 μm and thickness of 20 ± 7 nm) by a simple homogeneous synthesis taking place at room temperature. In structural terms, no differences are observed between our layered materials and those obtained hydrothermally. However, dynamic susceptibility measurements alert about different arrangements of the magnetic sublattices, which have been rationalized with structural DFT calculations. This work provides an extremely easy bottom-up method to obtain high-quality 2D crystals based on α-CoIIhydroxides,paving the way for the development of fundamental studies and applications.

关键词： Two-dimensional(2D)materials Layered hydroxides Hexagonal morphology Bottom-up synthesis Magnetism

Growth of Micropropagated Solanum tuberosum L.Plantlets under Artificial Solar Spectrum and Different Mono-and Polychromatic LED Lights

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Horticultural Plant Journal 2022年第2期8卷 205-214页

作者： Olga v.Grishchenko Eugeny P.Subbotin Irina v.Gafitskaya Yulia v.vereshchagina Elena v.Burkovskaya Yulia A.Khrolenko valeria P.Grigorchuk Olga v.Nakonechnaya victor P.Bulgakov Yuri N.Kulchin Federal Scientific Center of the East Asia Terrestrial Biodiversity Far Eastern Branch of the Russian Academy of SciencesVladivostok 690022Russia Institute of Automation and Control Processes Far Eastern Branch of the Russian Academy of SciencesVladivostok 690041Russia

In agriculture,LED light sources have increasingly replaced the standard luminescent lamps and have acquired an important role in plant micropropagation.We studied the effect of different light sources such as narrow-band LEDs(bright blue,blue,green,yellow,deep red,and red)and wide-band LEDs(cold white,white,warm white,full spectrum,and an artificial solar spectrum sun box constructed by us)on development of potato plantlets in vitro.White luminescent lamps were used as a control.The light intensity of 49μmol·m^(-2)·s^(-1)was provided in all light treatments.We showed that the long-wave narrow-band light treatments were inapplicable for potato micropropagation,because plantlets were weak with small leaves,inhibited roots,and significantly elongated stems.Blue lights provided growth of shortened plantlets with large leaves,well-growing roots,and abundant green mass.The chlorophyll content was lower under blue and bright blue light and was at the same level in the remained treatments.Significant differences in the stomatal apparatus development were observed depending on the light source.These differences were not always reflected in the plantlet phenotype:e.g.,plantlets under blue and bright blue lights showed no differences in any characteristics except stomatal density and size of stomatal guard cells.We found no significant effect of blue light portion in the white lights and full spectrum on plantlet growth.An artificial solar spectrum sun box was the most suitable for potato micropropagation,because it supported the development of plantlets with good fitness,uniform internodes length,abundant roots and green mass accumulation.

关键词： Solanum tuberosum LED Artificial solar light Growth Micropropagation

Biogenesis of TiO_(2) nanoparticles:An approach to prove multidisciplinary application

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Green Synthesis and Catalysis

Green Synthesis and Catalysis 2022年第2期3卷 150-155页

作者： W.Sherine victor S.vijayakumar E.vidhya v.N.Punitha M.Nilavukkarasi PG and Research Department of Botany AVVM Sri Pushpam CollegePoondi(Affiliated to Bharadhidasan University)Thanjavur 613503India Department of Nanotechnology Noorul Islam Centre for Higher EducationKumarakoilKanyakumari 629180India

Nanomaterials with countless potential applications in the Natural Science and Clinical Pharmaceutics have offered the prospects of developing new nanomaterials.The analysis of green TiO_(2) nanoparticles synthesized with Limonia acidissima(L.acidissima)aqueous peel extract was described in this study.The green fabricated TiO_(2) nanoparticles were characterized by Uv-vis spectrum,XRD,FT-IR,and FE-SEM with EDX.Green TiO_(2) nanoparticles exhibited excellent antimicrobial and photodegradation activities.Further it has demonstrated the release of reactive oxygen species(ROS)and proven mitochondrial membrane potential in a dosage manner of 0-100μg/mL.The statistics were also examined with P valuesvisages the TiO_(2) nanoparticles as a function of L.acidissima aqueous extracts with a wide range of multidisciplinary applications.

关键词： Biomaterials Nanoparticles L.acidissima Anticancer Antimicrobial and photodegradation activities

Methods for recording the time profile of single ultrashort pulses of electron beams and discharge currents in real-time mode

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High voltage 2016年第1期1卷 43-51页

作者： victor F.Tarasenko Dmitry v.Rybka Institute of High Current Electronics Siberian Branch Russian Academy of SciencesTomsk 634055Russia

The collectors for measuring the time profile of a current pulse of the runaway electron beam that are generatedunder atmospheric pressure are described. An analysis of changes in pulse shape depending on the bandwidth of theregistration path with a temporal resolution of up to 20 ps was performed. It is shown that the electron beam detectedbehind small-diameter diaphragms has a complex structure, which depends on the parameters of the gas diode. Thereis a design of the current shunts with a temporal resolution of up to 100 ps in this study. Measurement techniques ofvoltage pulses with subnanosecond and nanosecond duration are briefly described.

关键词： ultrashort pulse recording