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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)esult 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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A review on the scale-up of high-shear wet granulation processes and the impact of process parameters

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Particuology 2024年第9期92卷 180-195页

作者： Ana Rita Alves Marta Filipe Simões Sérgio Simões João Gomes University of Coimbra CERESDepartment of Chemical EngineeringFaculty of Sciences and TechnologyRua Sílvio Lima3030-790CoimbraPortugal Bluepharma-Indústria Farmacêutica São Martinho do BispoCoimbra3045-016Portugal Faculty of Pharmacy University of CoimbraAzinhaga de Santa Comba3000-548CoimbraPortugal

Wet granulation is one of the most important agglomeration processes,and high-shear granulation(HSG)one of the most employed technologies in the pharmaceutical *** most critical process parameters of HSG are discussed in this *** main concern in scaling up the wet granulation process is the differences between scales,which prevent the particles from having the same experience across all *** scale-up of wet granulation processes is commonly divided into two categories:engineering and attribute-based *** engineering-based scale-up approach is a strategy based on dimensional analysis and an attribute-based supported on the principles of“equifinality”,where process variables are adjusted to obtain equivalent granule *** work presents the effect of different HSG process parameters on the scale-up,as well as the use of process analytical tools(PAT)and modelling *** aim is to review applied scale-up approaches in HSG and discuss benefits and *** is proven why the scale-up for oral solid pharmaceutical products is still considered a hot topic and a very challenging task for development and engineering teams.

关键词： High-shear wetgranulation Parametric-based Attribute-based Physics-based modelling Impeller design Scale-up

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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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Tuning MXenes Towards Their Use in Photocatalytic Water Splitting

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Energy & Environmental Materials 2024年第6期7卷 321-331页

作者： Diego Ontiveros Sergi Vela Francesc Viñes Carmen Sousa Departament de Ciència de Materials i Química Física&Institut de Química Teòrica i Computacional(IQTCUB) Universitat de Barcelonac/Martíi Franquès 1-1108028 BarcelonaSpain

Finding appropriate photocatalysts for solar-driven water(H_(2)O)splitting to generate hydrogen(H_(2))fuel is a challenging task,particularly when guided by conventional trial-and-error experimental ***,density functional theory(DFT)is used to explore the MXenes photocatalytic properties,an emerging family of two-dimensional(2D)transition metal carbides and nitrides with chemical formula M_(n+1)X_(n)T_(x),known to be semiconductors when having T_(x)*** than 4,000 MXene structures have been screened,considering different compositional(M,X,T_(x),and n)and structural(stacking and termination position)factors,to find suitable MXenes with a bandgap in the visible region and band edges that align with the water-splitting half-reaction *** from bandgap analysis show how,in general,MXenes with n=1 and transition metals from group III present the most cases with bandgap and promising sizes,with C-MXenes being superior to *** band alignment calculations of candidate systems with a bandgap larger than 1.23 eV,the minimum required for a water-splitting process,Sc_(2)CT_(2),Y_(2)CT_(2)(T_(x)=Cl,Br,S,and Se)and Y_(2)CI_(2)are highlighted as adequate photocatalysts.

关键词： Density Functional Theory MXenes Photocatalysis Water Splitting

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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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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》 Institute of Volcanology and Seismology Far Eastern Branch of the Russian Academy of Sciences Computing Center of the Far Eastern Branch of the Russian Academy of Sciences

This paper presents a method for retrieving optical parameters from volcanic sulfate aerosols from the AHI radiometer on board the Himawari-8 satellite. The 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 droplets. The 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 droplets. Using 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： H2SO4 Himawari-8 mass loading optical thickness the Karymsky volcano volcanic ash volcano

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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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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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