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Longitudinal dependence of the forecast accuracy of the ionospheric total electron content in the equatorial zone

Geodesy and Geodynamics 2024年第5期15卷 528-541页

作者： Artem Kharakhashyan olga Maltseva Institute for Physics Southern Federal University344090Russia

The longitudinal dependence of the behavior of ionospheric parameters has been the subject of a number of works where significant variations are *** also applies to the prediction of the ionospheric total electron content(TEC),which neural network methods have recently been widely ***,the results are mainly presented for a limited set of *** paper examines the longitudinal dependence of the TEC forecast accuracy in the equatorial *** this case,the methods are used that provided the best accuracy on three meridians:European(30°E),Southeastern(110°E)and American(75°W).Results for the stations considered are analyzed as a function of longitude using the Jet Propulsion Laboratory Global Ionosphere Map(JPL GIM)for *** results are for 2 h ahead and 24 h ahead *** was found that in this case,based on the metric values,three groups of architectures can be *** first group included long short-term memory(LSTM),gated recurrent unit(GRU),and temporal convolutional networks(TCN)models as a part of unidirectional deep learning models;the second group is based on the recurrent models from the first group,which were supplemented with a bidirectional algorithm,increasing the TEC forecasting accuracy by 2-3 *** third group,which includes the bidirectional TCN architecture(BiTCN),provided the highest *** this architecture,according to data obtained for 9 equatorial stations,practical independence of the TEC prediction accuracy from longitude was observed under the following metrics(Mean Absolute Error MAE,Root Mean Square Error RMSE,Mean Absolute Percentage Error MAPE):MAE(2 h)is 0.2 TECU approximately;MAE(24 h)is 0.4 TECU approximately;RMSE(2 h)is less than 0.5 TECU except Niue station(RMSE(2 h)is 1 TECU approximately);RMSE(24 h)is in the range of 1.0-1.7 TECU;MAPE(2 h)<1%except Darwin station,MAPE(24 h)<2%.This result was confirmed by data from additional 5 stations that formed latitudinal chains in the

关键词： Ionosphere Total electron content Forecasting BiGRU BiLSTM BiTCN Temporal convolution

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Vibrational Suspension of Two Cylinders in a Rotating Liquid-Filled Cavity with a Time-Varying Rotation Rate

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2127-2137页

作者： olga Vlasova Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPermSibirskaya614990Russia

The dynamics of rotating hydrodynamic systems containing phase inclusions are interesting due to the related widespread occurrence in nature and *** influence of external force fields on rotating systems can be used to control the dynamics of inclusions of various *** inclusions is of current interest for space *** low gravity,even a slight vibration effect can lead to the appearance of a force acting on phase inclusions near a solid *** vibrations are applied to multiphase hydrodynamic systems,the oscillating body intensively interacts with the fluid and introduces changes in the related flow *** in the fluid flow lead to the appearance of an averaged *** a result,the body is repelled from the cavity boundary and takes a position at a certain distance from *** vibrationally-induced movement of phase inclusions in liquids can be used to improve various technological processes(for example,when degassing and cleaning liquids from solid inclusions,mixing various components,etc.).This study presents a relevant methodology to study the averaged vibrational force acting on a pair of free cylindrical bodies near the oscillating wall of a *** is paid to the region of moderate and low dimensionless frequencies when the size of the inclusion is consistent with the thickness of the Stokes boundary *** dynamics of these bodies is considered in a horizontal cylindrical cavity with a fluid undergoing modulated *** average lift force of a vibrational nature is measured by the method of quasi-stationary suspension of bodies whose density differs from the density of the liquid in a static centrifugal force *** developed technique makes it possible to determine the dependence of the lift force on vibration parameters and the distance from the oscillating boundary at which solid inclusions are *** is shown that in the region of moderate dimensionless frequencies,the averag

关键词： Solid bodies rotational oscillations viscous fluid lift force

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Retrieval of Volcanic Sulfate Aerosols Optical Parameters from AHI Radiometer Data

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Advances in Atmospheric Sciences 2024年第10期41卷 1953-1968页

作者： Andrei FILEI olga GIRINA Aleksei SOROKIN Far-Eastern Center of State Research Center for Space Hydrometeorology«Planeta» Khabarovsk 680000Russia Institute of Volcanology and Seismology Far Eastern Branch of the Russian Academy of Sciences Petropavlovsk-Kamchatsky 683006Russia Computing Center of the Far Eastern Branch of the Russian Academy of Sciences Khabarovsk 680000Russia

This paper presents a method for retrieving optical parameters from volcanic sulfate aerosols from the AHI radiometer on board the Himawari-8 *** proposed method is based on optical models for various mixtures of aerosol components from volcanic clouds,including ash particles,ice crystals,water drops,and sulfate aerosol *** application of multi-component optical models of various aerosol compositions allows for the optical thickness and mass loading of sulfate aerosol to be estimated in the sulfuric cloud formed after the Karymsky volcano eruption on 3 November 2021.A comprehensive analysis of the brightness temperatures of the sulfuric cloud in the infrared bands was performed,which revealed that the cloud was composed of a mixture of sulfate aerosol and water *** models of various aerosol compositions allows for the satellite-based estimation of optical parameters not only for sulfate aerosol but also for the whole aerosol mixture.

关键词： H_(2)SO_(4) volcano Himawari-8 mass loading volcanic ash optical thickness the Karymsky volcano

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K^(+) channel-mediated retarded maturation of interneurons and its role in neurodevelopmental disorders

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Neural Regeneration Research 2024年第7期19卷 1403-1404页

作者： Kaizhen Li Daria Savitska olga Garaschuk Laboratory of Systems Neuroscience Department of PhysiologyUniversity of BernBernSwitzerland Institute of Physiology Department of NeurophysiologyEberhard Karls University of TübingenTübingenGermany

De novo mutations in genes encoding K^(+)channels are implicated in many severe neurodevelopmental ***,mutations in KCNA2,encoding the Shaker-type voltage-gated K^(+)channel Kv1.2,and KCNJ2,encoding the inwardly rectifying K^(+)channel Kir2.1,associate with focal and generalized epilepsies,brain atrophy,autism,ataxia and hereditary spastic paraplegia(Syrbe et al.,2015;Masnada et al.,2017;Cheng et al.,2021).

关键词： disorders atrophy

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Comparison of the performance and dynamics of the asymmetric single-sided and symmetric double-sided vibro-impact nonlinear energy sinks with optimized designs

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International Journal of Mechanical System Dynamics 2024年第3期4卷 303-316页

作者： Petro Lizunov olga Pogorelova Tetyana Postnikova Department of Constructive Mechanics Kyiv National University of Construction and ArchitectureKyivUkraine Research Institute of Structural Mechanics Kyiv National University of Construction and ArchitectureKyivUkraine

The operation of symmetric double-sided and asymmetric single-sided vibro-impact nonlinear energy sinks(DSVI NES and SSVI NES)is considered in this *** methodology of optimization procedures is *** is emphasized that the execution of optimization procedures is ambiguous,allows for a great deal of arbitrariness,and requires experience and intuition on the part of the *** are a lot of damper parameter sets providing similar attenuation of the primary structure(PS)*** is shown that the efficiency of such mitigation for both VI NES types with optimized parameters is ***,their dynamic behavior differs *** system with the attached DSVI NES exhibits calm dynamics with periodic motion and symmetrical bilateral impacts on both *** system with attached SSVI NES exhibits rich complex dynamics when the exciting force frequency is *** modes of different periodicity with different numbers of asymmetric impacts per cycle on the PS directly and on the obstacle alternate with various irregular regimes,namely,chaotic mode,intermittency,and crisis-induced *** regions of bilateral impacts are narrow and located near resonance;they are narrower for a system with an attached DSVI *** a system with an attached SSVI NES,there are wider areas of asymmetric unilateral impacts.

关键词： vibro-impact damper nonlinear energy sink single-sided double-sided vibrations mitigation optimization

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Averaged Dynamics of Fluids near the Oscillating Interface in a Hele-Shaw Cell

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Fluid Dynamics & Materials Processing 2024年第4期20卷 847-857页

作者： Anastasia Bushueva olga Vlasova Denis Polezhaev Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia

The steady flow in a Hele-Shaw cell filled with fluids with a high viscosity contrast in the presence of fluid oscillations is experimentally *** control of oscillatory dynamics of multiphase systems with interfaces is a challenging technological *** consider miscible(water and glycerol)and immiscible(water and high-viscosity silicone oil PMS-1000)fluids under subsonic oscillations perpendicular to the *** show that the interface shape depends on the amplitude and frequency of *** interface is undisturbed only in the absence of *** small amplitudes,the interface between water and glycerol widens due to *** the critical amplitude is reached,the interface becomes unstable to the fingering instability:Aqueous fingers penetrate the high-viscosity glycerol and induce intensive mixing of miscible fluids and associated decay of the *** the disappearance of the fingers,the interface takes a U-shape in the central part of the cell.A similar effect is observed for immiscible fluids:The oscillating interface tends to bend to the side of a high-viscosity ***,when the critical amplitude is reached,the fingering instability arises at the convex *** paper focuses on the causes of bending of the initially undisturbed interface between miscible or immiscible *** this purpose,we measure the steady flow velocity near the interface and in the bulk of a high-viscosity fluid using Particle Image Velocimetry(PIV).

关键词： Hele-Shaw cell oscillations steady flow miscible fluids immiscible fluids interface

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Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

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Railway Engineering Science 2024年第3期32卷 361-383页

作者： olga Nabochenko Mykola Sysyn Norman Krumnow Szabolcs Fischer Institute of Railway Systems and Public Transport Technical University of DresdenDresdenGermany Rhomberg Sersa Deutschland GmbH BerlinGermany Central Campus Győr Széchenyi István UniversityGyorHungary

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance ***,the mechanism of the irregularities initiation and development is *** motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted *** long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional ***,wide sleepers had higher twist and cross-section level *** present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper *** DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional ***,the cross-level differential settlements are almost the same for both *** particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper *** flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level *** mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper *** further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the *** DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

关键词： Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation

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A new tectonic model for the Itmurundy Zone,central Kazakhstan:linking ocean plate stratigraphy,timing of accretion and subduction polarity

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Geoscience Frontiers 2024年第4期15卷 245-273页

作者： Inna Safonova Ilya Savinskiy Alina Perfilova olga Obut Alexandra Gurova Sergei Krivonogov Southwest Jiaotong University Xi’an Road 999ChengduChina Sobolev Institute of Geology and Mineralogy SB RASKoptyuga Ave.3NovosibirskRussia Novosibirsk State University Pirogova St.2NovosibirskRussia Trofimuk Institute of Petroleum Geology and Geophysics SB RAS Koptyuga Ave.3NovosibirskRussia

The Itmurundy Zone of Central Kazakhstan is a key structure in the core of the Kazakh Orocline representing a typical Pacific-type orogenic belt hosting accretionary complex,ophiolite massifs and serpentinite mé*** main controversies in the existing tectonic models of the Itmurundy Zone are about the timing of subduction and accretion,the direction and kinematics of subduction and the number of oceanic plates.A new model for the early Paleozoic tectonic story of the Itmurundy Zone is postulated in this paper,based on new detailed geological and U-Pb detrital zircon age data,combined with previously documented geological,U-Pb age,microfossil,geochemical and isotope data from igneous rocks,deep-sea sediments and greywacke *** present study employs the Ocean Plate Stratigraphy(OPS)model to explain the tectonic processes involved in the evolution of the Itmurundy Zone and to pre-sent a holistic story of Ordovician oceanic plate(s),which accretion formed an accretionary *** detailed mapping allows distinguishing three types of OPS assemblages:(1)Chert-dominated,(2)OIB-hosting,and(3)*** U-Pb ages of detrital zircons from sandstones of OIB and Chert types show unimodal distributions with similar main peaks of magmatism at 460-455 Ma in the provenance,and their maximum depositional ages(MDA)span 455-433 *** samples from OPS Type 3 show the peaks of magmatism both at ca.460 Ma and the MDA of 452 Ma and 459 Ma,*** MDA of sandstones and microfossils data from chert show the younging of strata to the south and SE in Types 1 and 2 and to NEE for Type 3(in present coordinates)suggesting double-sided subduction to the NNW and SEE and,accordingly,the co-existence of pieces of two oceanic plates in Ordovician *** U-Pb zircon data from both igneous and clastic rocks indicate a period of subduction erosion in early Ordovician *** a whole,the accreted OPS units of the Itmurundy Zone record the timing of subduction and accre

关键词： Central Asian Orogenic Belt Accretionary complex Magmatic rocks Sedimentary rocks Subduction polarity Lithospheric plates

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Fine-needle aspiration technique under endoscopic ultrasound guidance:A technical approach for RNA profiling of pancreatic neoplasms

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2663-2672页

作者： Sabina Sherafedinovna Seyfedinova olga Aleksandrovna Freylikhman Polina Sergeevna Sokolnikova Konstantin Aleksandrovich Samochernykh Anna Aleksandrovna Kostareva olga Viktorovna Kalinina Evgeniy Gennadievich Solonitsyn Research Laboratory of Digestive Cancer Almazov Medical Research CentreSaint-Petersburg 197341Russia Research Laboratory of Molecular and Cellular Modeling and Gene Therapy Almazov Medical Research CentreSaint-Petersburg 197341Russia Head of Russian Neurosurgical Institute Named after Prof.A.L.Polenova Russian Neurosurgical Institute Named after Prof.A.L.PolenovaSaint-Petersburg 191014Russia Head of Institute of Molecular Biology and Genetics Almazov National Medical Research CentreSaint-Petersburg 197341Russia Research Laboratory of Autoimmune and Autoinflammatory Diseases Almazov National Medical Research CentreSaint-Petersburg 197341Russia

BACKGROUND Early diagnosis of pancreatic ductal adenocarcinoma(PDAC)has been a longstanding *** prognosis of patients with PDAC depends on the stage at *** is necessary to identify biomarkers for the detection and differentiation of pancreatic tumors and optimize PDAC sample preparation procedures for DNA and RNA *** molecular studies are done using paraffin-embedded blocks;however,the integrity of DNA and RNA is often compromised in this ***,RNA isolated from human pancreatic tissue samples is generally of low quality,in part,because of the high concentration of endogenous pancreatic RNAse activity *** To assess the potential of endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)to obtain specimens from pancreatic neoplasms for subsequent RNA molecular profiling,including next-generation sequencing(NGS).METHODS Thirty-four EUS-FNA samples were included in this study:PDAC(n=15),chronic pancreatitis(n=5),pancreatic cysts(n=14),mucinous cysts(mucinous cystic neoplasia/intraductal papillary mucinous neoplasia)n=7,serous cystic neoplasms n=5,and pseudocysts n=*** material consisted of cyst fluid and cyst wall samples obtained by through-the-needle biopsy(TTNB).Samples were stored at -80℃ until *** purity(A260/230,A260/280 ratios),concentration,and integrity(RIN)were ***-time polymerase chain reaction was conducted on all samples,and small RNA libraries were prepared from solid mass *** RNA was successfully extracted from 29/34(85%)EUS-FNA samples:100% pancreatic adenocarcinoma samples,100% chronic pancreatitis samples,70% pancreatic fluid cyst samples,and 50%TTNB *** relative expression of GAPDH and HPRT were obtained for all successfully extracted RNA samples(n=29)including lowquality RNA *** concentration and nonoptimal RIN values(no less than 3)of RNA extracted from EUS-FNA samples did not prevent NGS library *** suitability of cyst fluid samples

关键词： Endoscopic ultrasound-guided,fine-needle aspiration Pancreatic cancer Pancreatic cysts RNA extraction Through-the-needle biopsy Next-generation sequencing

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Environmental Impact Assessment of Onshore Wind Farms in the Region of Central Greece Using a Modified RIAM Method

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Journal of Environmental & Earth Sciences 2024年第1期6卷 71-82页

作者： olga Korozi Dimitra G.Vagiona Department of Spatial Planning and Development Aristotle University of ThessalonikiThessaloniki 54124Greece

Wind energy is one of the most basic forms of renewable energy,which shows an increasing rate of development worldwide and also at the European ***,this rapid deployment of wind farms makes the need for an impact assessment of this type of projects on the natural and man-made environment *** present paper aims to identify and assess the environmental impacts of wind farm projects in the Region of Central Greece.A modified Rapid Impact Assessment Matrix(RIAM)method is used for this *** methodology includes the identification of the existing onshore wind farm projects in the study area,the appropriate modifications of the RIAM method to respond to the characteristics of the projects and the study area,the qualitative assessment of their potential impacts during construction and operational phases and the computation of the Environmental Performance Grade(EPG)of projects based on the pro-posed modified RIAM *** results reveal that although there are some slight negative impacts on the natural environment of the study area,the examined wind farms contribute positively both to the atmosphere and to the socio-economic environment of the *** study extends the potential for using RIAM as a tool in environmental impact assessment studies of renewable energy projects.

关键词： Environmental impact assessment Environmental components Region of central Greece Rapid impact assessment matrix(RIAM) Environmental performance grade(EPG)

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