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Three-Dimensional Convection in an Inclined Porous Layer Subjected to a vertical Temperature Gradient

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Fluid Dynamics & Materials Processing 2024年第9期20卷 1957-1970页

作者： ivan Shubenkov Tatyana Lyubimova Evgeny Sadilov Computational Fluid Dynamics Laboratory Institute of Continuous Media Mechanics UB RASPerm614068Russia Theoretical Physics Department Perm State UniversityPerm614990Russia

In this paper,we study the onset and development of three-dimensional convection in a tilted porous layer saturated with a *** layer is subjected to a gravitational field and a strictly vertical temperature ***,problems of thermal convection in tilted porous media saturated with a liquid are studied by assuming constant different temperatures at the boundaries of the layer,which prevent these systems from supporting conductive(non-convective)*** boundary conditions considered in the present work allow a conductive state and are representative of typical geological *** an earlier work,we carried out a linear stability analysis of the conductive *** was shown that at any layer tilt angles,the most dangerous type of disturbances are longitudinal ***,a non-zero velocity component exists in *** the present work,threedimensional non-linear convection regimes are *** original three-dimensional problem is reduced to two-dimensional one with an analytical expression for the velocity z-component v_(z)=v_(z)(x,y).It is shown that the critical Rayleigh number values obtained through numerical solutions of the obtained 2D problem by a finite difference method for different layer inclination angles,are in a good agreement with those predicted by the linear *** number of convective rolls realized in nonlinear calculations also fits the linear theory predictions for a given cavity *** carried out at low supercriticalities show that a direct bifurcation takes *** increasing supercriticality,no transitions to other convective regimes are *** situation studied in this problem can be observed in oil-bearing rock formations under the influence of a geothermal temperature gradient,where the ensuing fluid convection can affect the distribution of oil throughout the layer.

关键词： Thermal convection inclined layer porous media vertical temperature gradient

Homing and migration of mesenchymal stromal cells: How to improve the efficacy of cell therapy?

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World Journal of Stem Cells 2016年第3期8卷 73-87页

作者： Ann De Becker ivan van Riet Department Clinical HematologyStem Cell Laboratory Universitair Ziekenhuis Brussel Vrije Universiteit Brussel (VUB)

Mesenchymal stromal cells(MSCs) are currently being investigated for use in a wide variety of clinical applications. For most of these applications, systemic delivery of the cells is preferred. However, this requires the homing and migration of MSCs to a target tissue. Although MSC hominghas been described, this process does not appear to be highly efficacious because only a few cells reach the target tissue and remain there after systemic administration. This has been ascribed to low expression levels of homing molecules, the loss of expression of such molecules during expansion, and the heterogeneity of MSCs in cultures and MSC culture protocols. To overcome these limitations, different methods to improve the homing capacity of MSCs have been examined. Here, we review the current understanding of MSC homing, with a particular focus on homing to bone marrow. In addition, we summarize the strategies that have been developed to improve this process. A better understanding of MSC biology, MSC migration and homing mechanisms will allow us to prepare MSCs with optimal homing capacities. The efficacy of therapeutic applications is dependent on efficient delivery of the cells and can, therefore, only benefit from better insights into the homing mechanisms.

关键词： Mesenchymal stromal cells Homing Bone marrow Homing receptors Extravasation

Observation of nonlinear fractal higher order topological insulator

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Light(Science & Applications) 2024年第11期13卷 2699-2714页

作者： Hua Zhong victor O.Kompanets Yiqi Zhang Yaroslav v.Kartashov Meng Cao Yongdong Li Sergei A.Zhuravitskii Nikolay N.Skryabin ivan v.Dyakonov Alexander A.Kalinkin Sergei P.Kulik Sergey v.Chekalin victor N.Zadkov Key Laboratory for Physical Electronics and Devices Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong University710049 Xi’anChina Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia

Higher-order topological insulators(HOTIs)are unique materials hosting topologically protected states,whose dimensionality is at least by 2 lower than that of the *** states in such insulators may be strongly confined in their corners which leads to considerable enhancement of nonlinear processes involving such ***,all nonlinear HOTIs demonstrated so far were built on periodic bulk lattice ***,we demonstrate the first nonlinear photonic HOTI with the fractal *** their fractional effective dimensionality,the HOTIs constructed here on two different types of the Sierpiński gasket waveguide arrays,may support topological corner states for unexpectedly wide range of coupling strengths,even in parameter regions where conventional HOTIs become *** demonstrate thresholdless spatial solitons bifurcating from corner states in nonlinear fractal HOTIs and show that their localization can be efficiently controlled by the input beam *** observe sharp differences in nonlinear light localization on outer and multiple inner corners and edges representative for these fractal *** findings not only represent a new paradigm for nonlinear topological insulators,but also open new avenues for potential applications of fractal materials to control the light flow.

关键词： materials flow topological

Anomalies of bromine in the estuarine sediments as a signal of floods associated with typhoons

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Chinese Journal of Oceanology and Limnology 2015年第6期33卷 1489-1495页

作者： ivan KALUGIN Anatolii ASTAKHOv Andrey DARIN Kirill AKSENTOv Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Science v.I.Il’ichev Pacific Oceanological Institute Far Eastern Branch Russian Academy of Science

X-ray fluorescence scanning with synchrotron radiation was performed to study sediment core records of floods in Amur Bay,Sea of *** of 3–8 mm with abnormally low bromine content were formed by the Razdolnaya River discharge to the central part of the bay during extreme floods,accompanied by severe storms at *** conditions in the region are typical for periods of deep tropical cyclones(typhoons),to which the distinguished interlayers were compared on the *** approach was made possible thanks to the high rate of sedimentation in the bay(3–5 mm/a) and low bioturbation of sediments under anoxic conditions.

关键词： X-ray fluorescence scanning typhoons sediments bromine continental shelf Sea of Japan Amur Bay

Optimization and kinetic modeling of waste lard methanolysis in a continuous reciprocating plate reactor

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2481-2490页

作者： Marija R.Miladinovic ivan J.Stojkovic Ana v.velickovic Olivera S.Stamenkovic ivana B.Bankovic-Ilic vlada B.veljkovic University of Nis Faculty of TechnologyBulevar osloboaenja 124Leskovac 16000Serbia University of Belgrade Faculty of Technology and MetallurgyKarnegijeva 4Belgrade 11000Serbia Serbian Academy of Sciences and Arts(SASA) Knez Mihailova 35Belgrade 11000Serbia

Continuous biodiesel production from a waste pig-roasting lard,methanol and KOH was carried out in a reciprocating plate reactor(RPR)using a factorial design containing three process factors,namely methanol/lard molar ratio,catalyst loading,and normalized height of the *** main goals were to optimize the influential process factors with respect to biodiesel purity using the response surface methodology and to model the kinetics of the transesterification reaction in order to describe the change of triacylglycerols(TAG)and fatty acid methyl esters(FAME)concentrations along the RPR *** first-order rate law was proved for both the reaction and the mass *** model of the changing reaction mechanism and mass transfer of TAG was also *** kinetic models agreed with the experimental concentrations of TAG and FAME determined along the RPR height.

关键词： Biodiesel Kinetics Optimization Reciprocating plate reactor Waste lard

AN ALABASTER SCULPTED HEADOFPTOLEMY v FROM THE PUSHKIN MUSEUMOFFINEARTS,MOSCOW,ANDHORUSASPECTS OF LATE PERIOD EGYPTIAN AND PTOLEMAIC KINGSHIP

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Journal of Ancient Civilizations 2023年第1期38卷 1-20,125页

作者： ivan A.Ladynin M.v.Lomonosov Moscow State University MoscowRussia

The typology of Ptolemaic royal sculpture has served as a theme of research for a number of scholars who have managed to achieve impressive results:two fundamental works must be *** earlier is Bildnisse der Ptolemaer by ***,which established a convincing correspondence between the well-attributed images of the Ptolemaic kings on their coins and their mostly uninscribed sculpted images.'The history of the research reveals that although the corpus of Ptolemaic sculpture gradually expanded,due to new finds and new publications,challenges to specific attributions proposed by Kyrieleis often proved to be a failure?A later work deserving a special mention is Portraits of the Ptolemies by ***,which proposed a well-founded scheme for the evolution of the Ptolemaic royal sculpture dividing it into nine groups(Groups A-E,G making a chronological sequence,Groups F,H-J uncertain and miscellaneous)'Quite expectedly,a problematic issue is the ultimate motive and final result of shifting from one such group to another:a grouping of objects is largely a formal task,and a scholar performing it is unlikely to concentrate simultaneously on the variety of political,ideological,and religious factors that could lie behind the emergence of the groups *** present article aims to offer a tentative explanation for the shift in the style of Ptolemaic sculpture that took place at the cusp of the 3rd and 2nd centuries BC,i.e.,the transition between Stanwick's "Group A"and "Group B."

关键词： dividing religious shifting

A class of high-mobility layered nanomaterials by design

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Journal of Materials Science & Technology 2023年第33期164卷 179-187页

作者： Dmitry v.Averyanov ivan S.Sokolov Oleg E.Parfenov Alexander N.Taldenkov Oleg A.Kondratev Andrey M.Tokmachev vyacheslav G.Storchak National Research Center “Kurchatov Institute” Kurchatov Sq.1Moscow 123182Russia

Design of materials with particular functional properties is indispensable albeit very *** and structural analogies can be helpful in this endeavor,especially when a particular combination of properties is sought *** aim is to bundle together 3 characteristics:high carrier mobility,magnetism,and scalability to nanomaterials in the form of a film–such a combination is particularly advantageous for ***,inspired by recent studies of MAl_(2)Si_(2)and related compounds,we develop magnetic EuAl_(2)Ge_(2)and non-magnetic SrAl_(2)Ge_(2)nanomaterials with high carrier *** syntheses employing sacrificial 2D templates result in epitaxial films of MAl_(2)Ge_(2)seamlessly integrated with *** syntheses are followed by a study of the atomic structure,magnetic and electron transport *** particular,the films demonstrate high carrier mobility,exceeding 10,000 cm^(2)v^(-1)s^(-1)in the case of EuAl_(2)Ge_(2),making the materials appealing for *** together,MAl_(2)Ge_(2)and MAl_(2)Si_(2)form a class of high-mobility layered nanomaterials.

关键词： High carrier mobility Magnetism SrAl_(2)Ge_(2) EuAl_(2)Ge_(2) Germanium

Observation of nonlinear disclination states

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Light(Science & Applications) 2023年第9期12卷 1818-1829页

作者： Boquan Ren Antonina A.Arkhipova Yiqi Zhang Yaroslav v.Kartashov Hongguang Wang Sergei A.Zhuravitskii Nikolay N.Skryabin ivan v.Dyakonov Alexander A.Kalinkin Sergei P.Kulik victor O.Kompanets Sergey v.Chekalin victor N.Zadkov Key Laboratory for Physical Electronics and Devices Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia

Introduction of controllable deformations into periodic materials that lead to disclinations in their structure opens novel routes for construction of higher-order topological insulators hosting topological states at *** of these topological states is consistent with the bulk-disclination correspondence principle,and is due to the filling anomaly that results in fractional charges to the boundary unit *** far,topological disclination states were observed only in the linear regime,while the interplay between nonlinearity and topology in the systems with disclinations has been never studied *** report here on the experimental observation of the nonlinear photonic disclination states in waveguide arrays with pentagonal or heptagonal disclination cores inscribed in transparent optical medium using the fs-laser writing *** transition between nontopological and topological phases in such structures is controlled by the Kekulédistortion coefficient r with topological phase hosting simultaneously disclination states at the inner disclination core and spatially separated from them corner-I,corner-II,and extended edge states at the outer edge of the *** show that the robust nonlinear disclination states bifurcate from their linear counterparts and that location of their propagation constants in the gap and,hence,their spatial localization can be controlled by their *** disclination states can be efficiently excited by Gaussian input beams,but only if they are focused into the waveguides belonging to the disclination core,where such topological states *** results open new prospects for investigation of nonlinear effects in topological systems with disclinations and are relevant for different areas of science,including Bose-Einstein and polariton condensates,where potentials with the disclinations can be created.

关键词： structure topological nonlinear

Does bilioenteric anastomosis impair results of liver resection in primary intrahepatic lithiasis?

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World Journal of Gastroenterology 2010年第27期16卷 3423-3426页

作者： Paulo Herman Marcos v Perini vincenzo Pugliese Julio Cesar Pereira Marcel Autran C Machado William A Saad Luiz AC D'Albuquerque ivan Cecconello Department of Gastroenterology Hospital Das Clínicas-University of So Paulo Medical SchoolSo Paulo-SP-CEP 05403-000BrazilPaulo HermanPraa Santos Coimbra10So Paulo-SP-CEP 05614-050Brazil

AIM:To evaluate the long-term results of liver resection for the treatment of primary intrahepatic *** factors,especially the impact of bilioenteric anastomosis on recurrence of symptoms were ***:Forty one patients with intrahepatic stones and parenchyma fibrosis/atrophy and/or biliary stenosis were submitted to liver *** was associated with a Roux-en-Y hepaticojejunostomy in all patients with bilateral stones and in those with unilateral disease and dilation of the extrahepatic biliary duct(>2 cm).Late results and risk factors for recurrence of symptoms or stones were ***:There was no operative *** a mean follow-up of 50.3 mo,good late results were observed in 82.9% of patients;all patients submitted to liver resection alone and 58.8% of those submitted to liver resection and hepaticojejunostomy were free of symptoms(P=0.0006).Patients with unilateral and bilateral disease showed good late results in 94.1% and 28.6%,respectively(P<0.001).CONCLUSION:Recurrence of symptoms in patients with hepaticojejunostomy showed that this may not be the ideal *** studies are needed to establish the best treatment for patients with bilateral stones or unilateral disease and a dilated extrahepatic duct.

关键词： Biliary lithiasis Bilioenteric anastomosis Cholangitis Intrahepatic lithiasis Liver resection