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infectious Disease Modelling 2017年第2期2卷 268-275页

作者： Alexandra smirnova Gerardo Chowell Department of Mathematics and Statistics Georgia State UniversityAtlantaUSA School of Public Health Georgia State UniversityAtlantaUSA Division of international Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA

Public health officials are increasingly recognizing the need to develop disease-forecasting systems to respond to epidemic and pandemic *** instance,simple epidemic models relying on a small number of parameters can play an important role in characterizing epidemic growth and generating short-term epidemic *** the absence of reliable information about transmission mechanisms of emerging infectious diseases,phenomenological models are useful to characterize epidemic growth patterns without the need to explicitly model transmission mechanisms and the natural history of the *** this article,our goal is to discuss and illustrate the role of regularization methods for estimating parameters and generating disease forecasts using the generalized Richards model in the context of the 2014e15 Ebola epidemic in West Africa.

关键词： Generalized Richards model Parameter estimation Regularization methods Epidemic forecasting Ebola

Peculiarities of the electrocaloric effect in relaxors

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Journal of Materiomics 2023年第1期9卷 223-228页

作者： Elena smirnova Galina Sotnikova Andrei Sotnikov Alexandr Kapralov Gennadiy Gavrilov ioffe institute 26 PolitekhnicheskayaSt Petersburg194021Russian Federation

A comprehensive study and detailed analysis of pyroelectric and electrocaloric effects in relaxor ferroelectrics based on lead magnesium niobate as a promising object for such investigations have been carried *** was found that even at the maximum values of pyroelectric coefficients the electrocaloric response inextricably linked with the pyroelectric effect does not exceed 1°C in the temperature range from 10 to 60°C under DC electric field up to 60 kV/*** conditions are the most demanded for the operation of electrocaloric cooling *** for the future as to increasing the efficiency of the main elements for such devices is discussed.

关键词： Relaxors Electrocaloric effect Pyroelectric effect

impact of lanthanum on the modification of HfO_2 films structure

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Journal of Rare Earths 2015年第8期33卷 857-862页

作者： T.P.smirnova L.V.Yakovkina V.O.Borisov Nikolaev institute of inorganic Chemistry SB RAS

LaxHf1-xOy thin films with various concentrations of La, homogeneous and nonhomogeneous distributions of elements throughout the films thickness was purposefully grown by CVD. The composition of the films and their chemical structures were characterized throughout the films thickness by X-ray photoelectron spectroscopy （XPS） and energy-dispersive X-ray spectrometry （EDXA）. A full picture of the film crystallinity was provided by the combination of grazing incidence X-ray diffraction （GiXRD） synchrotron radiation （SR） and high resolution transmission electron microscopy （HR TEM）. it was shown that La acted as ＂molar volume modulator＂ and stabilized the nonequilibrium at T≤1300 ℃ cubic phases. The samples with La content in range of 7 at.%〈CLa〈22 at.% were materials with fluorite-type （Fm-3m） structure. The pyroehlore phase formation was observed at -18 at.% La content. The correlation between the La-doped content and the films microstructure was revealed.

关键词： Hf1-xLaxOy films solid solutions X-ray diffraction microstructure rare earths

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COLLAGEN AS iN ViVO QUANTiTATiVE FLUORESCENT BiOMARKERS OF ABNORMAL TiSSUE CHANGES

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Journal of innovative Optical Health Sciences 2012年第2期5卷 49-57页

作者： O.D.smirnova D.A.ROGATKiN K.S.LiTViNOVA Moscow Regional Research and Clinical institute\MONiKi"Named after M.F.Vladimirskiy Shepkina Str.61/2 Moscow 129110Russian Federation

Collagen is an endogenousfluorophore that accounts for about 70%of all proteins of human skin,so it can be an optical marker for structural abnormalities in tissues registered by laserfluorescent diagnostics in *** the examples of such abnormalities as scars,scleroderma and basal cell carcinoma,this study shows the differences between coefficients offluorescent contrast k_(f)(λ)of abnormalities from the ones for healthy tissues atfluorescent excitation wavelength 360380 *** is shown that scars and dysplasia are characterized by reduced values of k_(f)(λ)for *** to high turbidity and phase heterogeneousness as well as variation of parameters of blood microcirculation and concentrations of other related chromophores,there is no mathematical model that precisely calculates the concentration of collagen in tissues only with the use of the value offluorescent signal ***,probably,the best marker of the pathological process is a comprehensive representation of k_(f)(λ)for all endogenousfluorophores,i.e.,for all used visible *** this case identification of abnormal tissues is quite possible by detecting some deviations of coefficients k_(f)(λ)for the optically identical and symmetrical regions of the human body.

关键词： Medical diagnostics spectroscopy fluorescence collagen scars

The Biologic Active Zones(BAZ) in the White,Greenland,and Labrabor Seas and its Climatological Modification:Comparative Study by Using Satellite and in-situ Data

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地学前缘 2009年第S1期16卷 120-121页

作者： smirnova Alexandra Vladimir V.Melentyev Melentyev Vladimir Vasilievsky Island

The authors of this work have made an attempt to research a habitat of three existing populations of Greenland seal and conditions of biologically active zones(BAZ) located,accordingly,in White, Greenland and Labrador *** seal is an ice-associated sea mammal,and climate warming can be a decisive factor for its *** the researches of changes of ice state parameters of subarctic water areas are an urgent problem

关键词： biologically active zones satellite microwave sounding

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Traffic flow sensitivity to visco-elasticity

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Theoretical & Applied Mechanics Letters 2016年第4期6卷 182-185页

作者： M.N. smirnova A.i. Bogdanova Zuojin Zhu N.N. Smirnov Faculty of Mechanics and Mathematics Moscow M.V. Lomonosov State University Moscow 119992 Russia Faculty of Engineering Science University of Science and Technology of China Hefei 230026 China Scientific Research institute for System Analysis of Russian Academy of Sciences Moscow 117218 Russia Saint Petersburg State Polytechnical University St. Petersburg 195251 Russia

This letter reports traffic flow sensitivity to visco-elasticity, with the traffic flow modeling briefly described at first and then used to do traffic flow simulations whose results can reflect the properties of spatial-temporal evolution of ring traffic flow. it reveals that visco-elasticity plays crucial role in formation of traffic flow patterns, implying that self-organization of traffic flow is crucial in determining traffic flow status.

关键词： Viscoelastic modeling Self-organization Traffic flow sensitivity Flow pattern formation

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Extension of Near-Wall Domain Decomposition to Modeling Flows with Laminar-Turbulent Transition

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Communications in Computational Physics 2022年第2期31卷 645-668页

作者： M.Petrov S.Utyuzhnikov A.Chikitkin N.smirnova Moscow institute of Physics&Technology Dolgoprudny 141700Russia Department of Mechanical Aerospace&Civil EngineeringThe University of ManchesterManchesterM139PLUK

The near-wall domain decomposition method(NDD)has proved to be very efficient for modeling near-wall fully turbulent *** this paper the NDD is extended to non-equilibrium regimeswith laminar-turbulent transition(LTT)for the first *** LTT is identified with the use of the e^(N)-method which is applied to both incompressible and compressible *** ismodified to take into account LTT in an *** addition,implementation of the intermittency expands the capabilities of NDD to model non-equilibrium turbulent flows with *** of the modified NDD approach is demonstrated on various test problems of subsonic and supersonic flows past a flat plate,a supersonic flow over a compression corner and a planar shock wave impinging on a turbulent boundary *** results of modeling with and without decomposition are compared in terms of wall friction and show good agreement with each other while NDD significantly reducing computational resources *** turns out that the NDD can reduce the computational time as much as three times while retaining practically the same accuracy of prediction.

关键词： Domain decomposition laminar-turbulent transition interface boundary condition near-wall flow low-Reynolds-number model

Room-temperature lasing from nanophotonic topological cavities

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Light(Science & Applications) 2020年第1期9卷 823-830页

作者： Daria smirnova Aditya Tripathi Sergey Kruk Min-Soo Hwang Ha-Reem Kim Hong-Gyu Park Yuri Kivshar Nonlinear Physics Center Research School of PhysicsAustralian National UniversityCanberraACT 2601Australia institute of Applied Physics Russian Academy of ScienceNizhny Novgorod 603950Russia Department of Physics Indian Institute of TechnologyDelhi 110016India Department of Physics Korea UniversitySeoul 02841Republic of Korea

The study of topological phases of light underpins a promising paradigm for engineering disorder-immune compact photonic devices with unusual *** with an optical gain,topological photonic structures provide a novel platform for micro-and nanoscale lasers,which could benefit from nontrivial band topology and spatially localized gap ***,we propose and demonstrate experimentally active nanophotonic topological cavities incorporating Ⅲ-Ⅴ semiconductor quantum wells as a gain medium in the *** observe room-temperature lasing with a narrow spectrum,high coherence,and threshold *** emitted beam hosts a singularity encoded by a triade cavity mode that resides in the bandgap of two interfaced valley-Hall periodic photonic lattices with opposite parity *** findings make a step towards topologically controlled ultrasmall light sources with nontrivial radiation characteristics.

关键词： lasing singularity narrow

impacts of Down-Up Hill Segment on the Threshold of Shock Formation of Ring Road Vehicular Flow

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Advances in Applied Mathematics and Mechanics 2023年第5期15卷 1315-1334页

作者： Zejing Hu M.N.smirnova N.N.Smirnov Yongliang Zhang Zuojin Zhu Faculty of Engineering Science University of Science and Technology of ChinaHefeiAnhui 230026China Faculty of Mechanics and Mathematics Lomonosov Moscow State UniversityMoscow119992Russia Anhui Xiang Shui Jian Pumped Storage Co. LTDWuhuAnhui 241083China

The study of impacts of down-up hill road segment on the density threshold of traffic shock formation in ring road vehicular flow is helpful to the deep understanding of sags’bottleneck *** are freeway segments along which the gradient increases gradually in the traffic *** main aim of this paper is to seek the density threshold of shock formation of vehicular flow in ring road with down-up hill segment,because down-up hill roadway segment is a source to cause capacity reduction that is an attractive topic in vehicular traffic *** seek the density threshold numerically,a viscoelastic continuum model[1]is extended and *** solve the model equations,a fifth-order weighted essentially non-oscillatory scheme for spatial discretization,and a 3rd order Runge-Kutta scheme for time partial derivative term are *** by existing observation data and the Navier-Stokes like model[2]extended as EZM is done before conducting extensive numerical *** ring road vehicular flow with three separated down-up hill segments,it is found that the density threshold of shock formation decreases monotonically with the relative difference of free flow speed,this variation can be simply fitted by a third order polynomial.

关键词： Down-up hill road segment viscoelastic continuum model sags’bottleneck effect density threshold WENO5 scheme

Spontaneous Ca2+ oscillations in subcellular compartments of vascular smooth muscle cells rely on different Ca2+ pools

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Cell Research 2004年第5期14卷 379-388页

作者： Olesya D. FEDORYAK,Yvonne SEARLS,irina V. smirnova,Douglas M. BURNS,Lisa STEHNO-BiTTEL Departments of Physical Therapy and Rehabilitation Sciences University of Kansas Medical Center Kansas City KS 66160 USA Departments of Physical Therapy and Rehabilitation Sciences University of Kansas Medical Center Kansas City KS 66160 USA Department of Anatomy and Cell Biology University of Kansas Medical Center Kansas City KS 66160 USA Departments of Physical Therapy and Rehabilitation Sciences University of Kansas Medical Center Kansas City KS 66160 USA VA Medical Center Kansas City MO 64128 USA Departments of Physical Therapy and Rehabilitation Sciences University of Kansas Medical Center Kansas City KS 66160 USA Department of Anatomy and Cell Biology University of Kansas Medical Center Kansas City KS 66160 USA

Spontaneous Ca2+ oscillations in vascular smooth muscle cells have been modeled using a single Ca2+ pool. This report describes spontaneous Ca2+ oscillations dependent on two separate Ca2+ sources for the nuclear versus cytoplas- mic compartments. Changes in free intracellular Ca2+ were monitored with ratiometric Ca2+- fluorophores using confo- cal microscopy. On average, spontaneous oscillations developed in 79% of rat aortic smooth muscle cells that were synchronous between the cytoplasm and nucleus. Reduction of extracellular Ca2+ (itude of the cytoplasmic oscillations with 48% of the oscillations asynchronous between the nuclear and cytoplasmic compartments. Similar results were obtained with the Ca2+ channel blockers, nimodipine and diltiazem. Arg-vasopressin (AVP) induced a rapid release of intracellular Ca2+ stores that was greater in the nuclear compartment (4.20 ± 0.23 ratio units, n = 56) than cytoplasm (2.54 ± 0.28) in cells that had spontaneously developed prior oscillations. Conversely, cells in the same conditions lacking oscillations had a greater AVP-induced Ca2+ transient in the cytoplasm (4.99 ± 0.66, n = 17) than in the nucleus (2.67 ± 0.29). Pre-treatment with Ca2+ channel blockers depressed the AVP responses in both compartments with the cytoplasmic Ca2+ most diminished. Depletion of internal Ca2+ stores prior to AVP exposure blunted the nuclear response, mimicking the response of cells that lacked prior oscillations. Spontaneous oscillating cells had a greater sarcoplasmic reticulum network than cells that did not oscillate. We propose that sponta- neous nuclear oscillations rely on perinuclear sarcoplasmic reticulum stores, while the cytoplasmic oscillations rely on Ca2+ influx.

关键词： oscillations vascular smooth muscle cells nuclear Ca2+ vasopressin thapsigargin diltiazem nimodipine.