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Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： Nina A.Vasilieva Liudmila e Savinetskaya andrey V.Tchabovsky A.N.Severtsov Institute of ecology and evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive *** analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects *** 48%of weaned pups survived to dispersal and 17%survived to *** life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early *** strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juveniles had lower life expectancy than the earliest *** overall effect of local juvenile density was *** lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juvenile quality and *** female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

Strong coupling and catenary field enhancement in the hybrid plasmonic metamaterial cavity and TMDC monolayers

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Opto-electronic Advances 2024年第5期7卷 20-32页

作者： Andergachew Mekonnen Berhe Khalil As’ham Ibrahim Al-Ani Haroldo T.Hattori andrey e.Miroshnichenko School of engineering and Technology University of New South Wales at CanberraNorthcott DriveCanberra ACT 2610Australia

Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy *** plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall ***,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter *** a result,strong plasmon-exciton coupling has been reported by introducing a single metallic ***,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic ***,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton *** demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or *** calculated Rabi splitting of Au-MoSe_2 and Au-WSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me *** plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature.

关键词： catenary-shaped field enhancement strong coupling plasmon exciton Rabi splitting

Factors that influence the results of indirect decompression employing oblique lumbar interbody fusion

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World Journal of Orthopedics 2024年第8期15卷 734-743页

作者： andrey e Bokov Svetlana Y Kalinina Mingiyan I Khaltyrov Alexandr P Saifullin Anatoliy A Bulkin Department of Neurosurgery Institute of Traumatology and OrthopedicsPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia Department of Traumatology Orthopedics and NeurosurgeryPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia

BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal *** the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical *** To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar *** This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal *** underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw *** results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical *** After indirect decompression employing anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Рe median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment *** patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root *** critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 *** Indirect decompression employing anterior reconstruction is achieved by the increase in disc height al

关键词： Indirect decompression Anterior reconstruction Central lumbar spinal stenosis Degenerative spondylolisthesis Lateral recess stenosis Spinal instability Oblique lateral interbody fusion

Impact of doping profiles on the formation of laser-active centers in bismuth-doped GeO_(2)–SiO_(2)glass fibers

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Photonics Research 2024年第2期12卷 260-270页

作者： SeRGeY ALYSHeV ALeXANDeR VAKHRUSHeV ALeKSANDR KHeGAI eLeNA FIRSTOVA KONSTANTIN RIUMKIN MIKHAIL MeLKUMOV LYUDMILA ISKHAKOVA andrey UMNIKOV SeRGeI FIRSTOV Prokhorov General Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center119333 MoscowRussia Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences 603951 Nizhny NovgorodRussia

Multi-wavelength-band transmission technology based on the exploitation of the extended spectral region is considered as a potential approach to increase the transmission capacity in the deployed fiber-optic communication *** development of optical amplifiers operating in the O-,e-,S-,and U-telecom bands is an extremely important challenge for the successful implementation of this ***-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom *** is due to the ability of Bi ions incorporated into glass network to form bismuth active centers(BACs)with specific optical properties,which are primarily determined by the glass *** this work,the impact of the doping profiles of both Ge atoms as glass modifiers and Bi ions on the BACs formation is studied using a series of bismuth-doped fibers fabricated by the modified chemical vapor deposition(MCVD)*** Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is *** is turned out that for high-Bi concentration regions,the conversion efficiency is very low(less than 10%).In addition,the relationship of the conversion efficiency to the distribution of Bi ions and/or Ge atoms is ***,a continuous-wave laser at 1.46μm with a record slope efficiency of 80%is demonstrated using a Bi-doped fiber with confined doping profile,where the Bi-to-BACs conversion efficiency is 35%.This paper provides new information which might help to facilitate understanding of the features of Bi-doped fibers and their potentially achievable characteristics.

关键词： fiber fibers bismuth

Neuromorphic nanocluster networks:Critical role of the substrate in nano-link formation

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Nano Research 2023年第7期16卷 10500-10506页

作者： Wenkai Wu Alexey V.Verkhovtsev Theodoros Pavloudis andrey V.Solov’yov Richard e.Palmer Nanomaterials Lab Faculty of Science and EngineeringSwansea UniversityBay CampusFabian WaySA18ENSwanseaUK MBN Research Center Altenhöferallee 360438 Frankfurt am MainGermany School of Physics Faculty of SciencesAristotle University of ThessalonikiGR-54124 ThessalonikiGreece

Atomic cluster-based networks represent a promising architecture for the realization of neuromorphic computing systems,which may overcome some of the limitations of the current computing *** formation and breakage of links between the clusters are of utmost importance for the functioning of these computing *** paper reports the results of molecular dynamics simulations of synapse(bridge)formation at elevated temperature and thermal breaking processes between 2.8 nmsized Au1415 clusters deposited on a carbon substrate,a model ***,we find that the bridge formation process is driven by the diffusion of gold atoms along the substrate,no matter how small the gap between the clusters *** complementary simulations of the bridge breaking process reveal the existence of a threshold bias voltage to activate bridge rupture via Joule *** results provide an atomistic-level understanding of the fundamental dynamical processes occurring in neuromorphic cluster arrays.

关键词： atomic-switch network nanoclusters nanoparticles(NPs) clusters on surfaces synapse neuromorphics molecular dynamics(MD)

Supercurrent decay in ballistic magnetic Josephson junctions

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npj Computational Materials 2022年第1期8卷 186-196页

作者： HervéNess Ivan A.Sadovskyy andrey e.Antipov Mark van Schilfgaarde Roman M.Lutchyn Department of Physics King’s College LondonStrand CampusLondonWC2R 2LSUK Microsoft Quantum Microsoft Station QUniversity of CaliforniaSanta BarbaraCA93106USA National Renewable energy Laboratory GoldenCO80401USA

We investigate transport properties of ballistic magnetic Josephson junctions and establish that suppression of supercurrent is an intrinsic property of the junctions,even in absence of *** studying the role of ferromagnet thickness,magnetization,and crystal orientation we show how the supercurrent decays exponentially with thickness and identify two mechanisms responsible for the effect:(i)large exchange splitting may gap out minority or majority carriers leading to the suppression of Andreev reflection in the junction,(ii)loss of synchronization between different modes due to the significant dispersion of the quasiparticle velocity with the transverse *** results for Nb/Ni/Nb junctions are in good agreement with recent experimental *** approach combines density functional theory and the Bogoliubov-de Gennes model and opens a path for material composition optimization in magnetic Josephson junctions and superconducting magnetic spin valves.

关键词： Josephson decay magnetic

Chiral carbon dots:synthesis,optical properties,and emerging applications

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Light(Science & Applications) 2022年第4期11卷 542-564页

作者： Aaron Doring elena Ushakova andrey L.Rogach Department of Materials Science and engineering and Centre for Functional Photonics(CFP)City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong SARChina. Center of Information Optical Technologies ITMO UniversitySaint Petersburg 197101Russia. Shenzhen Research Institute City University of Hong Kong518057 ShenzhenChina

Carbon dots are luminescent carbonaceous nanoparticles that can be endowed with chiral properties,making them particularly interesting for biomedical applications due to their low cytotoxicity and facile *** recent years,synthetic efforts leading to chiral carbon dots with other attractive optical properties such as two-photon absorption and circularly polarized light emission have *** start this review by introducing examples of molecular chirality and its origins and providing a summary of chiroptical spectroscopy used for its *** approaches used to induce chirality in nanomaterials are *** the main part of this review we focus on chiral carbon dots,introducing their fabrication techniques such as bottom-up and top-down chemical syntheses,their morphology,and optical/chiroptical *** then consider emerging applications of chiral carbon dots in sensing,bioimaging,and catalysis,and conclude this review with a summary and future challenges.

关键词： properties synthesis chiral

Rare earth elements(Ree)and isotope composition(δ^(13)C andδ^(18)O)of manganese ores of Chiatura deposit(Georgia):features of ore formation and genesis

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Acta Geochimica 2023年第4期42卷 779-801页

作者： Vladimir N.Kuleshov andrey Yu.Bychkov Irina Yu.Nikolaeva Maria e.Tarnopolskaya Geological Institute Russian Academy of SciencesPyzhevskii Per.7MoscowRussia 119017 Lomonosov Moscow State University Leninskie Gory1MoscowRussia 119899

The rare earth elements(Ree)geochemistry and the isotope(δ^(13)C,δ^(18)O)composition of manganese ores of the Chiatura(Georgia)deposit were *** of the major features of all types of manganese ores is negative cerium(Ce/Ce*_(PAAS))anomaly and the absence of europium(eu/eu*_(PAAS))*** oolitic manganese ores were formed in oxic shallow marine *** content and distribution of Rees(in particular Ce and eu)in these ores are connected mainly with ferrous *** performed C-and O-isotope research in Mn-carbonates(oolitic and massive)has indicated that carbonate ores were formed by the participation of isotopic ally light CO_(2)which is a result of the oxidation of organic matter in the sediment strata by reducing environments of early diagenesis(and,partially,catagenesis)*** negative cerium anomalies in the studied carbonate ores reflect the specific Ree patterns in pore waters of sediments of earlier isdiagenesis zone of the Oligocene Chiatura's *** deficiency of cerium in this zone remains debatable and requires further *** of manganese carbonates took place multistage by the input of incisional solutions of different chemistry into sea bottom waters and *** absence of europium anomaly indicates about lack of hydrothermal solution input.

关键词： Ree Cerium anomaly Carbon and oxygen isotope geochemistry Oxide and carbonate manganese ores Chiatura deposit

Submonolayer eu superstructures—A class of 2D magnets

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Nano Research 2023年第1期16卷 1500-1506页

作者： Dmitry V.Averyanov Ivan S.Sokolov Alexander N.Taldenkov Oleg e.Parfenov andrey M.Tokmachev Vyacheslav G.Storchak National Research Center“Kurchatov Institute” Kurchatov Sq.1Moscow 123182Russia

Two-dimensional(2D)magnetic materials promise unconventional properties and quantum phases as well as advances in ultracompact *** of 2D magnets often reaches a single monolayer but in general can go beyond this limit,as demonstrated by 2D magnetism of submonolayer eu superstructures coupled with *** question is whether the submonolayer magnetism constitutes a general ***,we demonstrate that regular eu lattices form a class of 2D magnets displaying various structures,stoichiometries,and chemical *** synthesized and studied a set of eu superstructures on Ge(001).Their magnetic properties are consistent with the emergence of a magnetic order such as ferro-or *** particular,control over the magnetic transition temperature by weak magnetic fields indicates the 2D nature of the *** together,eu/Ge and eu/Si superstructures seed a nucleus of the research area addressing the emergence of magnetism in submonolayer chemical species.

关键词： two-dimensional(2D)magnetism submonolayer superstructure surface reconstruction germanium