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How Common can the Origin of Clusters Cha Ⅰ, Cha Ⅱ, ∈Cha and η Cha be?

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Research in Astronomy and Astrophysics 2024年第5期24卷 28-34页

作者： v.v.Bobylev A.T.Bajkova Pulkovo Astronomical Observatory St.-Petersburg 196140Russia

The trajectories of the groupings η Cha,∈Cha and Cha I,Cha II,constructed backward in time,have been *** concluded that the hypothesis about the joint formation of all four of these clusters from one molecular cloud cannot be completely ***,10–15 Myr ago,all these four clusters were located at approximately the same height above the plane of the ***,the gas-dust clouds from which all these four clusters were formed were located on one broad *** is possible that the appearance of the Cha I,Cha II,∈Cha and η Cha clusters may be associated with the impact on such a front of shock waves formed after supernova explosions in the Scorpius–Centaurus *** estimates of the kinematic ages of the clusters Cha I and Cha II are obtained as 0.12±0.19 and 0.05±0.15,*** is shown that the minimum size of the Cha I-north and Cha I-south clusters corresponded to the time of 0.55±0.24 Myr and 0.04±0.18 Myr ago,respectively,and approximately1.5 Myr ago the distance between the trajectories of these two groupings was minimal.

关键词： stars distances-stars kinematics and dynamics-galaxies star formation

Cross-method Analysis of Corotation Radii Data Set for Spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 95-110页

作者： v.S.Kostiuk A.A.Marchuk A.S.Gusev Sternberg Astronomical Institute Lomonosov Moscow State UniversityUniversitetsky pr.13119234 MoscowRussia Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1196140 St.PetersburgRussia Saint Petersburg State University Universitetsky pr.28198504 St.PetersburgRussia

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its *** the literature,there are plenty of methods to estimate this value,but do these measurements have any consistency?In this work,we collected a data set of corotation radius measurements for 547 galaxies,300 of which had at least two *** initial analysis reveals that most objects have rather inconsistent corotation radius ***,a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of *** findings do not have any relation to spiral type,Hubble classification,or presence of a *** other reasons,obtained results could be explained by the transient nature of spirals in a considerable part of *** have made our collected data sample publicly available,and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies fundamental parameters-galaxies kinematics and dynamics-galaxies structure

Crafting chirality in three dimensions via a novel fabrication technique for bound states in the continuum metasurfaces

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Light(Science & Applications) 2024年第3期13卷 390-392页

作者： Zaid Haddadin Anna My Nguyen Lisa v.Poulikakos Department of Electrical&Computer Engineering University of California San DiegoLa JollaCAUSA Department of Mechanical&Aerospace Engineering University of California San DiegoLa JollaCAUSA Program of Materials Science&Engineering University of California San DiegoLa JollaCAUSA

An additional deposition step was added to a multi-step electron beam lithographic fabrication process to unlock the height dimension as an accessible parameter for resonators comprising unit cells of quasi-bound stat... 详细信息

关键词： dimensions dimension intrinsic

Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles

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Plasma Science and Technology 2024年第9期26卷 32-39页

作者： victor F TARASENKO Dmitry v BELOPLOTOv Alexei N PANCHENKO Dmitry A SOROKIN Institute of High Current Electronics Siberian BranchRussian Academy of SciencesTomsk 634055Russia National Research Tomsk State University Tomsk 634050Russia

The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark *** and negative nanosecond voltage pulses with an amplitude of tens of kilovolts were ***-resolved images of the discharge development were taken with a fourchannel Intensified Charge Coupled Device(ICCD)*** minimum delay between the camera channels could be as short as≈0.1 *** made it possible to study the gap breakdown process with subnanosecond *** was observed that a wide-diameter streamer develops from the high-voltage pointed *** ionization processes near the grounded pin electrode started when the streamer crossed half of the *** bridging the gap by the streamer,a diffuse discharge was *** development of spark leaders from bright spots on the surface of the pointed electrodes was observed at the next *** was found that the rate of development of the spark leader is an order of magnitude lower than that of the wide-diameter *** thin luminous tracks were observed against the background of a discharge plasma *** has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles.

关键词： needle electrodes short voltage pulses atmospheric air streamer breakdown diffuse and spark discharges scattering metal particles

Interatomic Interaction Models for Magnetic Materials:Recent Advances

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Chinese Physics Letters 2024年第6期41卷 54-66页

作者： Tatiana S.Kostiuchenko Alexander v.Shapeev Ivan S.Novikov Emanuel Institute of Biochemical Physics RAS 4 Kosygin StreetMoscow119334Russian Federation Independent investigator

Atomistic modeling is a widely employed theoretical method of computational materials *** has found particular utility in the study of magnetic ***,magnetic empirical interatomic potentials or spinpolarized density functional theory(DFT)served as the primary models for describing interatomic interactions in atomistic simulations of magnetic ***,in recent years,a new class of interatomic potentials known as magnetic machine-learning interatomic potentials(magnetic MLIPs)has *** MLIPs combine the computational efficiency,in terms of CPU time,of empirical potentials with the accuracy of DFT *** this review,our focus lies on providing a comprehensive summary of the interatomic interaction models developed specifically for investigating magnetic *** also delve into the various problem classes to which these models can be ***,we offer insights into the future prospects of interatomic interaction model development for the exploration of magnetic materials.

关键词： materials interaction empirical

Why lowland riparian trees are difficult to use for streamflow reconstruction

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Journal of Forestry Research 2024年第3期35卷 219-230页

作者： Xiaomei Peng Shengchun Xiao Bao Yang Quanyan Tian vladimir v.Shishov Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geography and Ocean Science Nanjing UniversityNanjing 210023People's Republic of China Institute of Fundamental Biology and Biotechnology Siberian Federal UniversityKrasnoyarskRussia 660041

Existing streamflow reconstructions based on tree-ring analysis mostly rely on species from upland,mainly montane areas,while lowland species(generally plain)areas are rarely *** limits the understanding of streamflow change history in the lowlands,which is an important basis for water resource *** study focused on Populus euphratica stands located along the main stream,eastern and western tributaries in the lower reaches of the Heihe River basin(HRb),in arid northwestern *** investigated how streamflow regulation interferes with ripar-ian trees in lowlands when they used for streamflow ***-ring width chronologies were developed and analyzed in conjunction with meteorological and hydrologic observation *** results show streamflow regulation leads in sharp fluctuations in the streamflow allocation between the eastern tributaries and western *** resulted in instability of the correlation between streamflow at the two tributaries and at the Zhengyixia hydrologic station,with corresponding fluctuations in radial growth of poplar trees on the banks of the two tributaries and at the *** regulation altered the natural patterns of seasonal streamflow below the station,changing the time window of poplar *** study provides useful insight into tree-ring width based streamflow reconstruction in the lowlands.

关键词： Tree-ring width-Dendrochronology Populus euphratica The Ejina Oasis Streamflow

RBC aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 53-65页

作者： M.K.Maksimov P.B.Ermolinskiy O.N.Scheglovitova N.N.Sklyankina A.v.Muravyov A.E.Lugovtsov A.v.Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia N.F.Gamaleya National Research Center for Epidemiology and Microbiology 18 Gamaleya StreetMoscow 123098Russia K.D.Ushinsky Yaroslavl State Pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RBCs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RBC properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(NO),which is mainly produced by endothelial cells(EC)from L-arginine amino acid in the circulatory *** the mechanisms of the RBC-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced NO on RBC aggregation and adhesion to endothelium;(2)the NO e®ect on RBC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RBC aggregation and adhesion to a monolayer of EC were studied using optical tweezers(OT).The RBC deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and Myrenne *** con¯rmed that NO increases deformability and decreases aggregation of *** showed that the soluble guanylate cyclase pathway appears to be the only NO signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RBC aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of NO production by ***,data related to L-arginine accumulation by endothelium were obtained:Necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,NO decreased the RBC-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RBC adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet N.Toksumakov Olga G.Matveeva Dmitriy v.Grudinin Kirill v.voronin Arslan Mazitov Konstantin v.Kravtsov Alexander v.Syuy Dmitry M.Tsymbarenko Mikhail S.Mironov Sergey M.Novikov Ivan Kruglov Davit A.Ghazaryan Andrey A.vyshnevyy Aleksey v.Arsenin valentyn S.volkov Kostya S.Novoselov Moscow Center for Advanced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene Institute(NGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

The effect of long-term application of nitrogen-rich fertilizers on soil resistome:A study of conventional and organic cropping systems

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Soil Ecology Letters 2024年第3期6卷 135-150页

作者： Alexey S.vasilchenko Evgenii O.Burlakov Darya v.Poshvina Denis S.Gruzdev Sergey v.Kravchenko Aleksandr v.Iashnikov Ning Ling Anastasia v.vasilchenko Laboratory of Antimicrobial Resistance Institute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia Research Institute of Mathematics Physics and Computer ScienceDerzhavin Tambov State UniversityTambovRussia International Integrated Research Laboratory for Climate Change Land Use and BiodiversityInstitute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia SciBear OU Tartu Mnt 67/1-13bKesklinna Linnaosa10115 TallinnEstonia Center for Grassland Microbiome State Key Laboratory of Grassland Agro-EcosystemsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China

Metagenomic studies of various soil environments have previously revealed the widespread distribution of antibiotic resistance genes(ARGs)around the *** this study,we applied shotgun metagenomics to investigate differences in microbial communities and resistomes in Chernozem soils that have been under long-term organic and conventional cropping *** organic cropping system was seeded with Triticum spelta without any *** conventional cropping system was seeded with Tríticum durum Desf and used mineral fertilizer(NPK),that resulted in an increased amount of total and available carbon and nitrogen in *** all samples,we identified a total of 21 ARG classes,among which the dominant were vancomycin,tetracycline and *** of soil microbial communities revealed differences between the studied fields in the relative abundances of 14 and 53 genera in topsoil and subsoil,*** analysis showed significant correlations(positive and negative)among 18 genera and 6 ARGs,as well as between these ARGs and some chemical properties of *** analysis of metagenome-assembled genomes revealed that Nitrospirota,Thermoproteota,Actinobacteriota and Binatota phyla of archaea and bacteria serve as hosts for glycopeptide and fluoroquinolone/tetracycline ***,the data obtained enrich knowledge about the consequences of human agricultural activities in terms of soil microbiome modification and highlight the role of nitrogen cycling taxa,including uncultivated genera,in the formation of soil resistome.

关键词： soil microbiome inorganic fertilizer nitrogen cycle uncultured bacteria chemolithotrophs Binatia