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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 University

The longitudinal dependence of the behavior of ionospheric parameters has been the subject of a number of works where significant variations are discovered. This 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 meridians. This paper examines the longitudinal dependence of the TEC forecast accuracy in the equatorial zone. In 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 2015. These results are for 2 h ahead and 24 h ahead forecast. It was found that in this case, based on the metric values, three groups of architectures can be distinguished. The 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 times. The third group, which includes the bidirectional TCN architecture(BiTCN), provided the highest accuracy. For 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

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

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Testing of new ionospheric models along the meridian 110°E over the Northern Hemisphere

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Geodesy and Geodynamics 2022年第6期13卷 544-553页

作者： olga maltseva Artem Kharakhashyan Tatyana Nikitenko Institute for Physics Southern Federal University344090Russia

Despite the continuous improvement of the widely used empirical model international reference ionosphere(IRI),the recently appeared new models must be tested *** along the meridians has the advantage of dealing with the latitudinal dependent *** paper uses new models of parameters foF2(critical frequency),TEC(total electron content),andτ(equivalent slab thickness of the ionosphere),which are of great importance for evaluating the effects of space ***-Plas,NNT2F2,and NTSM models were tested using data from 6 ionosondes located along the meridian 110°E in March *** is shown that the IRI-Plas model provides the closest values to experiment with respect toτ,while the NTSM model provides a rather limited reflection of the latitude *** of foF2(NNT2F2)have shown that,the NNT2F2 model provides good conformity with experimental values in this area,but it is very dependent on the TEC processing *** latitudinal dependences of foF2 obtained with TEC and polynomial dependenceτ(Appr)showed the presence of positive deviations from medians not only during disturbances but also quiet periods,longitudinally at the meridian.

关键词： Ionosphere Modeling Total electron content Critical frequency Meridian 110°E

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The effect of space weather on the ionosphere at the 110°meridian during CAWSES-Ⅱperiod

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Geodesy and Geodynamics 2021年第2期12卷 93-101页

作者： olga maltseva Tatyana Nikitenko Institute for Physics Southern Federal University344090Rostov-on-DonStachky190Russia

Space weather determines the state of the ionosphere,which is especially important to know during *** study this state,the period of March 7-17,2012,which was recommended by SCOSTEP for detailed studies and called CAWSES-II,was *** this period,the behavior of parameters of the solar wind(SW)and the interplanetary magnetic field(IMF)show a number of *** this paper,we study their relationship with the total electron content(TEC)and the critical frequency(foF2)of the ionosphere at the 110°meridian,near which several ionosondes are located,in the range of 20°N-62.5°*** correlation coefficients of TEC and foF2 with the SW and IMF parameters for the month and the selected period are *** ionosphere showed the considered disturbances in different ways in different latitudinal zones:negative anomalies are observed at high latitudes,and positive ones at low latitudes.A distinctive feature is the presence of signs of a super-fountain *** of TEC and foF2 from their medians can be *** IRI model reacted in the latitude range 40°N-62.5°N in the form of negative anomalies,although positive anomalies were observed in the *** lower latitudes,no reaction was *** all factors(F10.7,Dst,Kp,IMF,Np),three zones(high-latitude,midlatitude,and low-latitude)are distinguished for different *** strongest influence of disturbances on the correlation coefficients is observed in the zone of 37.5°N 62.5°N.

关键词： Ionosphere Space weather Total electron content Correlation

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Comparison of TEC prediction methods in mid-latitudes with GIM maps

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Geodesy and Geodynamics 2020年第3期11卷 174-181页

作者： olga maltseva Galina Glebova Institute for Physics Southern Federal University344090Rostov-on-DonStachky190Russia

There are many long-term and short-term prediction methods of Total Electron Content(TEC) that need to be tested for each specific region. Recently, much attention has been paid to testing TEC models in high-, low-latitude and equatorial regions. This paper compares the TEC prediction methods in the midlatitude zone according to the data of the Juliusruh, Rostov, Manzhouli stations in 2008 and 2015. For a long-term prediction, the IRI-Plas and Ne Quick models are compared with the Global Ionospheric Maps(GIM) presented by the Jet Propulsion Laboratory(JPL) and the Technical University of Catalonia(UPC).For a short-term prediction, the Standard Persistence Model(SPM) method, a 27 day median model, and the proposed short-term prediction method are compared for one day ahead. It is shown that for all stations the IRI-Plas model provides better compliance with GIM maps than the Ne Quick model irrespective of a solar activity level. An average absolute error lays in the range of 3 e3.5 TECU, relative root square mean(RMS) error in the range of 22 e27% in 2015 and 1.7 e2 TECU, 20 e25% in 2008. For the Ne Quick model, these estimates were 6.7 e8.2 TECU and 42 e45% in 2015 and 2.2 e3.6 TECU, 30 e37% in2008. For the short-term forecast, the best results were obtained by the SPM method with an average absolute error in the range of 1.95 e2.15 TECU in 2015 and 0.59 e0.98 TECU in 2008, a relative RMS error in the range of 17 e21% in 2015, 11.5 e15% in 2008. For the proposed short-term prediction method, these errors were 2.04 e2.2 TECU and 12 e14% in 2015 and 0.7 e1.0 TECU, 7 e11% in 2008. Using medians, the errors were 3.1 e3.4 TECU and 17 e21% in 2015 and 1.0 e1.3 TECU, 10 e15% in 2008. The dependence of results on the Dst-index was obtained.

关键词： Ionosphere Middle latitudes TEC(total electron content) GIM(global ionospheric map) Prediction methods

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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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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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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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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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Detection and evaluation of different morphological forms of Mycoplasma hominis in human semen

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Asian Journal of Andrology 2024年第1期26卷 71-76页

作者： Elizaveta Bragina Tatyana Sorokina Avtandil Chogovadze Yulia Shevchenko Vyacheslav Chernykh olga Barkhatova Irina Rakovskaya Research Centre for Medical Genetics Moscow 115522Russia A.N.Belozersky Institute of Physico-Chemical Biology Lomonosov Moscow State University Moscow 119992Russia Reprolab Limited Liability Company Moscow 119333Russia N.I.Pirogov Russian National Research Medical University Moscow 117997Russia Federal Government Budgetary Institution"National Research Center for Epidemiology and Microbiology Named after Honorary Academician N.F.Gamaleya of the Ministry of Health of the Russian Federation" Moscow 123098Russia

Recently discovered microcolonial forms of Mycoplasma hominis(***)and their impact on human spermatogenesis are *** spermatozoa of 125 fertile men(sperm donors;from Reprobank[Reproductive Tissue Bank,Moscow,Russial)and of 93 patients with fertility problems(from the Federal State Budgetary Institution"Research Centre for Medical Genetics[RCMG]",Moscow,Russia)were *** colonies of *** and microcolonies were detected by molecular biological methods,culture of bacteria,and transmission electron *** unique structure of microcolonial cells,in which the cytoplasmic cylinder is surrounded by concentric electron-dense and electron-light layers with a periodicity of 12-14 nm,and the ability of microcolonial cells to attach to spermatozoa are *** patients with lower sperm quality,microcolonies of *** were detected 2.5 times more frequently than classical *** detection of microcolonies in the ejaculate and the frequent isolation of microcolonies from sperm samples of patients with fertility problems suggest that microcolonial cells may be one cause of infertility.

关键词： ejaculate fertility Mycoplasma hominis spermatogenesis transmission electron microscopy

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