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Research in Astronomy and Astrophysics 2016年第9期16卷 123-136页

作者： Elena Shimanovskaya vasiliy bruevich Elena bruevich Sternberg Astronomical Institute Moscow State University

The atmospheric activity of the Sun and Sun-like stars is analyzed involving observations from the HK-project at the Mount Wilson Observatory, the California and Carnegie Planet Search Program at the Keck and Lick Observatories and the Magellan Planet Search Program at the Las Campanas Observatory. We show that for stars of E G and K spectral classes, the cyclic activity, similar to the 11-yr solar cycle, is different： it becomes more prominent in K-stars. Comparative study of Sun-like stars with different levels of chromospheric and coronal activity confirms that the Sun belongs to stars with a low level of chromospheric activity and stands apart among these stars by its minimum level of coronal radiation and minimum level of variations in photospheric flux.

关键词： Sun activity -- Sun-like stars activity

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Investigation of Cavitation in NaCl Solutions in a Sonochemical Reactor Using the Foil Test Method

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1093-1102页

作者： Michael Kuchinskiy Tatyana Lyubimova Konstantin Rybkin Anastasiia Sadovnikova vasiliy Galishevskiy Institute of Continuous Media Mechanics UB RAS Perm614013Russia Faculty of Physics Perm State UniversityPerm614068Russia

Ultrasonic baths and sonochemical reactors are widely used in industrial applications dealing with surface cleaningand chemical synthesis. The processes of erosion, cleaning and structuring of the surface can be typically controlledby changing relevant influential parameters. In particular, in this work, we experimentally investigate theeffect of NaCl concentration (0–5.5 mol/L) on the erosion of an aluminum foil under ultrasonic exposure at afrequency of 28 kHz. Special attention is paid to the determination of cavitation zones and their visualizationusing heat maps. It is found that at low NaCl concentration (0.3 mol/L), the foil destruction rate is higher thanin distilled water. At higher concentrations of salt, cavitation takes place mainly in the upper part of the container.

关键词： Ultrasound NaCl solution foil test cavitation activity

Major- and Trace- Element Chemistry of Clinopyroxene and Amphibole from High-Mg Diorite in Chelyabinsk Massif(Urals): Insights into Petrogenesis and Magma Source Constraints

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Journal of Earth Science 2024年

作者： Tatiana Osipova Gennadiy Kallistov Maria Chervyakovskaya vasiliy Chervyakovskiy Zavaritsky Institute of Geology and Geochemistry，Ural Branch of RAS

Field- and petrographic investigations， together with microanalytical major- and trace-element studies， were carried out on clinopyroxene and amphibole from high-Mg diorite in the subduction-related Chelyabinsk granitic massif to understand its petrogenesis and source. The clinopyroxene composition (high Mg#， Cr-content， sum of REE and Ti/Eu ratio; depletion in HREE; negative Eu-anomaly) indicates that it formed from a reduced melt derived from a mantle source metasomatized by fluids/melts having crustal affinity. Melt compositions in equilibrium with clinopyroxene and amphibole were calculated using solid/liquid partition coefficients. The high Nb/Y and Zr/Y ratio values of a liquid simulated from clinopyroxene， which appears to have very similar characteristics to sanukitoid melts， indicate a low degree of melting of the mantle source. Melt simulated from amphibole is more evolved and more felsic (dacitic). It displays a geochemical “amphibole fractionation” signature， indicating the peritectic transformation of clinopyroxene to amphibole in the lower crust. Rock textures and major element mineral compositions suggest that further amphibole was precipitated directly from the melt in the middle crust. The results show that the Chelyabinsk high-Mg diorite was probably formed as a cumulate from sanukitoid-like melt during its ascent and cooling below dacitic liquidus inside the amphibole stability field.

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Impacts of interactions with low-mineralized water on permeability and pore behavior of carbonate reservoirs

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Energy Geoscience 2024年第4期5卷 278-290页

作者： Dmitriy A.Martyushev Inna N.Ponomareva vasiliy I.Chernykh Shadfar Davoodi Yousef Kazemzadeh Tianshou Ma Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPermRussia School of Earth Sciences&Engineering Tomsk Polytechnic UniversityLenin AvenueTomskRussia Enhanced Oil Recovery(EOR)Research Center IOR/EOR Research InstituteShiraz UniversityShirazIran State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuanPR China

Laboratory filtration experiments are employed to investigate effective well killing while minimizing its impacts on surrounding *** novelty of this experimental study lies in the prolonged exposure of rock samples to the killing fluid for seven days,corresponding to the average duration of well workovers in the oilfields in Perm Krai,*** findings indicate that critical factors influencing the interactions between rocks and the killing fluid include the chemical composition of the killing fluid,the mineralogical composition of the carbonate rocks,reservoir pressure and temperature,and the contact *** analyses using multi-scale X-ray computed tomography,field emission scanning electron microscopy,and X-ray diffraction were conducted on samples both before and after the well killing *** experiments were performed using real samples of cores,crude oil,and the killing *** results from this study indicate that low-mineralized water(practically fresh water)is a carbonate rock *** water causes the dissolution of rock components,the formation of new calcite crystals and amoeba-like secretions,and the migration of small particles(clay,quartz,and carbonates).The formation of deep channels was also *** assessment reveals that the change in the pH of the killing fluid indicates that the observed mineral reactions were caused by carbonate *** combined phenomena led to a decrease in the total number of voids in the core samples,which was 25%on average,predominantly among voids measuring between 45 and 70μm in *** change in the pore distribution in the bulk of the samples resulted in decreases in porosity of 1.8%and permeability of 67.0%in the studied core *** results from this study indicate the unsuitability of low-mineralized water as a well killing fluid in carbonate *** composition of the killing fluid should be optimized,for example,in terms of the ionic composition of water,

关键词： Fine particle Clay mineral Low-mineralized water Geochemical dissolution Carbonate reservoir

Self-assembled high-entropy nitride multilayer coating

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Rare Metals 2024年第6期43卷 2876-2883页

作者： Xiang-Yu Zhang Yan Liu vasiliy Pelenovich Xiao-Mei Zeng Jie Liu Qiang Wan Alexander Pogrebnjak Long-Jian Xue Zhi-Wen Chen Yan Lei Bing Yang School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China Hubei JiuFengShan Future Science and Technology Laboratory Wuhan 420000China Institute of Technological Sciences of Wuhan University Wuhan 430072China Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration Wuhan UniversityWuhan 430072China College of Engineering Huazhong Agricultural UniversityWuhan 430070China Sumy State University Sumy 40007Ukraine Institute of Materials Science Slovak University of Technology in BratislavaJána Bottu2591724 TrnavaSlovak Republic Shenzhen Research Institute of Wuhan University Shenzhen 518057China

The development of advanced materials and construction of multilayer structure contribute to enhancing the performance of protective coatings,further improving the industrial productivity and conserving *** this paper,the self-assembled high-entropy nitride(HEN)AlCrNbSiTiN multilayer coating was designed by harnessing the plasma distribution characteristics and depos-ited by arc ion plating using single target.

关键词： coating energy multilayer

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Composite Control of Nonlinear Singularly Perturbed Systems via Approximate Feedback Linearization

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International Journal of Automation and computing 2020年第4期17卷 610-620页

作者： Aleksey Kabanov vasiliy Alchakov Sevastopol State University Sevastopol 299053Russian Federation

This article is devoted to the problem of composite control design for continuous nonlinear singularly perturbed(SP)system using approximate feedback linearization(AFL)*** essence of AFL method lies in the feedback linearization only of a certain part of the original nonlinear *** to AFL approach,we suggest to solve feedback linearization problems for continuous nonlinear SP system by reducing it to two feedback linearization problems for slow and fast subsystems *** resulting AFL control is constructed in the form of asymptotic composition(composite control).Standard procedure for the composite control design consists of the following steps:1)system decomposition,2)solution of control problem for fast subsystem,3)solution of control problem for slow subsystem,4)construction of the resulting control in the form of the composition of slow and fast *** main difficulty during system decomposition is associated with dynamics separation condition for nonlinear SP *** overcome this,we propose to change the sequence of the design procedure:1)solving the control problem for fast state variables part,2)system decomposition,3)solving the control problem for slow state variables part,4)construction of the resulting composite *** this way,fast feedback linearizing control is chosen so that the dynamics separation condition would be met and the fast subsystem would be *** application of the proposed approach is illustrated through several examples.

关键词： Approximate feedback linearization(AFL) composite control nonlinear singularly perturbed system order reduction decomposition

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Concept on the pathogenesis and treatment of primary biliarycirrhosis

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World Journal of Gastroenterology 2006年第45期12卷 7250-7262页

作者： vasiliy Ivanovich Reshetnyak Scientific Research Institute of General Reaniamatology Russia Academy of Medical SciencesMoscowRussia

Primary biliary cirrhosis (PBC) is an organ-specific autoimmune disease that predominantly affects women and is characterized by chronic, progressive destruction of small intrahepatic bile ducts with portal inflammation and ultimately fibrosis, leading to liver failure in the absence of treatment. Little is known about the etiology of PBC. PBC is characterized by anti-mitochondrial antibodies and destruction of intrahepatic bile ducts. The serologic hallmark of PBC is the presence of auto-antibodies to mitochondria, especially to the E2 component of the pyruvate dehydrogenase complex (PDC). Current theories on the pathogenesis of PBC favor the hypothesis that the disease develops as a result of an inappropriate immune response following stimulation by an environmental or infectious agent. Some reports suggest that xenobiotics and viral infections may induce PBC. The pathogenetic mechanism is believed to be caused by a defect in immunologic tolerance, resulting in the activation and expansion of self-antigen specific T and B lymphocyte clones and the production of circulating autoantibodies in addition to a myriad of cytokines and other inflammatory mediators. This leads to ductulopenia and persistent cholestasis, by developing end-stage hepatic-cell failure. In this review are given our own and literary data about mechanisms of development of intrahepatic cholestasis and possible ways of its correction.

关键词： Primary biliary cirrhosis Pathogenesis Treatment

New insights into the pathogenesis of primary biliary cholangitis asymptomatic stage

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世界胃肠病学杂志:英文版 2023年第37期29卷 5292-5304页

作者： vasiliy Ivanovich Reshetnyak Igor Veniaminovich Maev Department of Propaedeutics of Internal Diseases and Gastroenterology A.I.Yevdokimov Moscow State University of Medicine and DentistryMoscow 127473Russia

Primary biliary cholangitis(PBC)is a chronic cholestatic progressive liver disease and one of the most important progressive cholangiopathies in *** to cholangiocytes triggers the development of intrahepatic cholestasis,which progresses to cirrhosis in the terminal stage of the *** data indicate that damage to biliary epithelial cells[(BECs),cholangiocytes]is most likely associated with the intracellular accumulation of bile acids,which have potent detergent properties and damaging effects on cell *** mechanisms underlying uncontrolled bile acid intake into BECs in PBC are associated with pH change in the bile duct lumen,which is controlled by the bicarbonate(HCO3-)buffer system“biliary HCO3-umbrella”.The impaired production and entry of HCO3-from BECs into the bile duct lumen is due to epigenetic changes in expression of the X-linked microRNA *** on the growing body of knowledge on the molecular mechanisms of cholangiocyte damage in patients with PBC,we propose a hypothesis explaining the pathogenesis of the first morphologic(ductulopenia),immunologic(antimitochondrial autoantibodies)and clinical(weakness,malaise,rapid fatigue)signs of the disease in the asymptomatic *** review focuses on the consideration of these mechanisms.

关键词： Primary biliary cholangitis Antimitochondrial autoantibodies MicroRNA 506 Inositol-1,4,5-trisphosphate receptor type 3 Chloride/bicarbonate anion exchanger 2 Biliary bicarbonate umbrella Dihydrolipoyl transacetylase(E2 subunit) Pyruvate dehydrogenase complex

Significance of dormant forms of Helicobacter pylori in ulcerogenesis

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World Journal of Gastroenterology 2017年第27期23卷 4867-4878页

作者： vasiliy Ivanovich Reshetnyak Tatiana Magomedalievna Reshetnyak VA Negovsky Research Institute of General Reanimatology of Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology Department of Systemic Connective Tissue Diseases VA Nasonova Research Institute of Rheumatology

Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease(PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However,the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms,but also contribute to the conversion of H. pylori into the resting(dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms,such as S-shaped,C-shaped,U-shaped,and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability.

关键词： Helicobacter pylori Forms of H. pylori Dormant forms of H. pylori Viable forms of H. pylori Non-viable forms of H. pylori Physiological states of H. pylori Culturable forms of H. pylori Unculturable forms of H. pylor Resuscitation of dormant H. pylori Ulcerogenesis

Concept of the pathogenesis and treatment of cholelithiasis

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World Journal of Hepatology 2012年第2期4卷 18-34页

作者： vasiliy Ivanovich Reshetnyak VA Negovsky Scientific Research Institute of General Reanimatology Russia Academy of Medical Sciences

Gallstone disease(GD) is a chronic recurrent hepatobiliary disease,the basis for which is the impaired metabolism of cholesterol,bilirubin and bile acids,which is characterized by the formation of gallstones in the hepatic bile duct,common bile duct,or *** is one of the most prevalent gastrointestinal diseases with a substantial burden to health care *** can result in serious outcomes,such as acute gallstone pancreatitis and gallbladder *** epidemiology,pathogenesis and treatment of GD are discussed in this *** prevalence of GD varies widely by *** prevalence of gallstone disease has increased in recent *** is connected with a change in lifestyle:reduction of motor activity,reduction of the physical load and changes to *** of the important benefits of early screening for gallstone disease is that ultrasonography can detect asymptomatic cases,which results in early treatment and the prevention of serious *** pathogenesis of GD is suggested to be multifactorial and probably develops from complex interactions between many genetic and environmental *** suggests that corticosteroids and oral contraceptives,which contain hormones related to steroid hormones,may be regarded as a model system of cholelithiasis development in *** achievement in the study of the physiology of bile formation and the pathogenesis of GD has allowed expanding indications for therapeutic treatment of GD.

关键词： Gallstone disease:Epidemiology Pathogenesis of cholesterol stones Treatment