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Left atrial appendage aneurysm: A case report

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World Journal of Clinical Cases 2020年第19期8卷 4443-4449页

作者： Dmitry Vladimirovich belov Vladimir Ivanovich Moskalev Dmitry Victorovich Garbuzenko nikolay Olegovich Arefyev Department of Hospital Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Hospital Surgery Federal Center for Cardiovascular SurgeryChelyabinsk 454033Russia Department of Faculty Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Pathological Anatomy and Forensic Medicine South Ural State Medical UniversityChelyabinsk 454092Russia

BACKGROUND An aneurysm of the left atrial appendage is one of the rare but potentially hazardous heart *** risk of lethal complications grows with its *** date,about 150 cases of this defect have been described in the *** present a case of left atrial appendage aneurysm with the deformation of the mitral valve and the left main coronary and circumflex artery,which required mitral valve annuloplasty and bifurcation *** SUMMARY A 58-year-old man presented to our hospital complaining of shortness of breath,general weakness,dizziness during physical exertion,and *** on the results of echocardiography,an aneurysm of the left atrium was suspected.A free-breathing real-time cine magnetic resonance imaging with electrocardiograph synchronization confirmed the diagnosis of left atrial appendage *** patient underwent an aneurysmectomy via a median sternotomy with cardiopulmonary *** transesophageal echocardiography revealed relative mitral insufficiency that was corrected with an annuloplasty *** coronary angiogram showed impaired blood flow in the left main coronary and circumflex artery and 60%*** this reason,bifurcation stenting was *** patient had an uneventful postoperative clinical course and was discharged from the hospital on the 10th day in a satisfactory *** Left atrial appendage aneurysm is a rare and dangerous heart pathology that requires surgery to prevent related complications.

关键词： Atrial appendage Aneurysm Mitral valve insufficiency Coronary stenosis Catheter ablation Case report

Effect of 0.3% Sc on microstructure, phase composition and hardening of Al-Ca-Si eutectic alloys

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Transactions of Nonferrous Metals Society of China 2017年第4期27卷 741-746页

作者： nikolay belov Evgenia NAUMOVA Torgom AKOPYAN National University of Science and Technology MISIS 4 Leninskiy pr. 4 Moscow 119049 Russia Institute of Russian Academy of Sciences A. A. Baikov Institute of Metallurgy and Material Science RASLeninskiy pr. 49 Moscow 119991 Russia

The phase composition,microstructure and hardening of aluminum-based experimental alloys containing0.3%Sc,0?14%Si and0?10%Ca(mass fraction)were *** experimental study(electron microscopy,thermal analysis and hardnessmeasurements)was combined with Thermo-Calc software simulation for the optimization of the alloy *** wasdetermined that the maximum hardening corresponded to the annealing at300?350°С,which was due to the precipitation of Al3Scnanoparticles with their further *** alloys falling into the phase region(Al)+Al4Ca+Al2Si2Ca have demonstrated asignificant hardening *** ternary eutectic(Al)+Al4Ca+Al2Si2Ca had a much finer microstructure as compared to the Al?Sieutectic,which suggests a possibility of reaching higher mechanical properties as compared to commercial alloys of the *** commercial alloys of the A356type,the model alloy does not require quenching,as hardening particles are formed in thecourse of annealing of castings.

关键词： Al-Ca-Si-Sc system alloy eutectic Al3Sc nanoparticles phase composition microstructure heat treatment hardening

Risk score for predicting abdominal complications after coronary artery bypass grafting

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World Journal of Cardiology 2020年第10期12卷 492-500页

作者： Dmitry Vladimirovich belov Dmitry Victorovich Garbuzenko Ksenia Alekseevna Abramovskikh nikolay Olegovich Arefyev Department of Hospital Surgery Federal Center of Cardiovascular Surgery of the Ministry of Health of Russia(the city of Chelyabinsk)Chelyabinsk 454003Russia Department of Faculty Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Hospital Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Pathological Anatomy and Forensic Medicine South Ural State Medical UniversityChelyabinsk 454092Russia

BACKGROUND Although early abdominal complications after coronary artery bypass grafting(CABG)with cardiopulmonary bypass(CPB)are rare,the associated mortality remains *** To develop a risk score for the prediction of early abdominal complications after CABG with *** This retrospective study was performed in the Federal State Budgetary Establishment“Federal Center of Cardiovascular Surgery”of the Ministry of Health of Russia(the city of Chelyabinsk)and included data of 6586 patients who underwent CABG with CPB during *** risk factors taken for evaluation were compared between patients with early abdominal complications(n=73)and without them(n=6513).We identified the most important risk factors and their influence on the development of early abdominal complications after CABG with *** Gender and the presence of postinfarction cardiosclerosis,chronic kidney disease,or diabetes in the anamnesis did not affect the occurrence of abdominal *** leading risk factors of the early abdominal complications after CABG with CPB were multifocal atherosclerosis,extracorporeal membrane oxygenation,intra-aortic balloon pump,atrial fibrillation,perioperative myocardial infarction,and the need for resternotomy in the postoperative *** average value of the predicted probability was 0.087±0.015 in patients with early abdominal complications after CABG with CPB and 0.0094±0.0003 in patients without these *** percentage of correct classification turned out to be 98.9%.After calculating a score for each of the leading risk factors,we counted a total score for each particular *** highest risk was noted in patients with a total score of 7 or *** The developed score predicts the risk of early abdominal complications after CABG with CPB and makes it possible to stratify patients by risk groups.

关键词： Coronary artery bypass grafting Cardiopulmonary bypass Abdominal complications Risk factors Risk score

Plasma-assisted oxidation of benzoic acid

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 513-521页

作者： Anna Khlyustova nikolay Sirotkin Laboratory of Chemistry of Hybrid Nanomaterials and Supermolecular Systems G.A.Krestov Institute of Solution Chemitry of Russian Academy of SciencesIvanovo 153045Russia

Plasma-assisted oxidation of organic com-pounds is one of the developing technologies for wastewater *** effectively accelerate degradation processes due to plasma generated reactive species and ultra-violet *** of BA in aqueous solutions by the atmospheric pressure glow discharge and underwater diaphragm discharge was studied and monitored by fluorescence and spectrophoto-metric *** type and solution pH affect the formation rates of mono-and dihydroxybenzoic *** derivatives were formed only by glow discharge *** yields of hydroxyl radical were estimated on the kinetics data for the hydroxylation of benzoic *** steps of the hydroxylation processes and further oxidation were described.

关键词： atmospheric pressure glow discharge under-water diaphragm discharge oxidation benzoic acid hydroxyl radical

Saffman–Taylor instability in eccentric cylinders at gaseous cavitation

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Friction 2024年第2期12卷 356-362页

作者： Anatoliy A.MONAKHOV nikolay BUKHARIN Institute of Mechanics Moscow State UniversityMoscow 119899Russia ThermoFluid Solutions Ltd. CalgaryAlberta T3G4E8Canada

A flow of silicon fluid in the gap between eccentric cylinders was studied *** condition of gaseous cavitation inception during the rotation of internal cylinder was *** was shown that at reduction of the gap between cylinders Saffman–Taylor instability appeared on surface of the internal cylinder and then gaseous cavitation was *** of one uniform gas formation appearance under this type of instability was demonstrated.

关键词： gaseous cavitation Saffman-Taylor instability eccentric cylinders friction lubrication theory

EXISTENCE OF SOLUTIONS OF nTH-ORDER NONLINEAR DIFFERENCE EQUATIONS WITH GENERAL BOUNDARY CONDITIONS

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Acta Mathematica Scientia 2020年第1期40卷 226-236页

作者： Alberto CABADA nikolay DIMITROV Departamento de Estatística Análise Matemática e OptimizaciónInstituto de MatemáticasFacultade de MatemáticasUniversidade de Santiago de CompostelaSantiago de CompostelaGaliciaSpain Depatment of Mathematics University of RuseRuse 7000Bulgaria

The aim of this paper is to prove the existence of one or multiple solutions of nonlinear difference equations coupled to a general set of boundary *** to do this,we construct a discrete operator whose fixed points coincide with the solutions of the problem we are looking ***,we introduce a strong positiveness condition on the related Green's function that allows us to construct suitable cones where to apply adequate fixed point *** we have the general existence result,we deduce,as a particular case,the existence of solutions of a second order difference equation with nonlocal perturbed Dirichlet conditions.

关键词： difference equation multiplicity of solutions Green's function positive solutions parameter dependence

Optimal control of natural resources in mining industry

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International Journal of Mining Science and Technology 2015年第2期25卷 193-198页

作者： Petrov nikolay Tanev Angel Electrical Engineering Electronics and AutomationTechnical University-Sofia Faculty of Mathematics and Informatics Sofia University

The paper focuses on the optimal control of natural resources in mining industry. The purpose is to pro- pose an optimal extraction series of these resources during the lifetime of the Mine＇s maintenance. Fol- lowing the proposed optimal control model, a sensitivity analysis has been performed that includes the interest rate impact on the optimal solution. This study shows that the increasing of the interest rate sti- mulates faster extraction of the resources. The discounting factor induces that the resource has to be extracted faster hut this effect is counterbalanced by the diminishing returns of the annual cash flow. At higher parameters of ＂alpha＂ close to one of the power function about 80% from the whole resource will be extracted during the first 4 years of object/mine maintenance. An existence of unique positive root with respect to return of investment has been proposed and proved by two ways： by the ＂method of chords＂ and by using specialized software.

关键词： Optimal control Natural resources Interest rate Sensitivity analysis Method of chords

On Concept Lattices for Numberings

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TSINGHUA SCIENCE AND TECHNOLOGY 2024年第6期29卷 1642-1650页

作者： Bazhenov, nikolay Mustafa, Manat Nurakunov, Anvar Sobolev Inst Math Lab Computabil Theory & Appl Log Novosibirsk 630090 Russia Nazarbayev Univ Sch Sci & Humanities Dept Math Astana 010000 Kazakhstan Natl Acad Sci Inst Math Bishkek 720071 Kyrgyzstan

The theory of numberings studies uniform computations for families of mathematical objects. In this area, computability-theoretic properties of at most countable families of sets S are typically classified via the corresponding Rogers upper semilattices. In most cases, a Rogers semilattice cannot be a lattice. Working within the framework of Formal Concept Analysis, we develop two new approaches to the classification of families S. Similarly to the classical theory of numberings, each of the approaches assigns to a family S its own concept lattice. The first approach captures the cardinality of a family S: if S contains more than 2 elements, then the corresponding concept lattice FC1(S) is a modular lattice of height 3, such that the number of its atoms to the cardinality of S. Our second approach gives a much richer environment. We prove that for any countable poset P, there exists a family S such that the induced concept lattice FC2 (S) is isomorphic to the Dedekind-MacNeille completion of P. We also establish connections with the class of enumerative lattices introduced by Hoyrup and Rojas in their studies of algorithmic randomness. We show that every lattice FC2 (S) is anti-isomorphic to an enumerative lattice. In addition, every enumerative lattice is anti-isomorphic to a sublattice of the lattice FC2 (S) for some family S.

关键词： theory of numberings concept lattice index set complete lattice enumerative lattice Formal Concept Analysis

Restructuring of the vascular bed in response to hemodynamic disturbances in portal hypertension

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World Journal of Hepatology 2016年第36期8卷 1602-1609页

作者： Dmitry Victorovich Garbuzenko nikolay Olegovich Arefyev Dmitry Vladimirovich belov Department of Faculty Surgery South Ural State Medical Uni-versity Department of Hospital Surgery South Ural State Medical University

In recent years, defined progress has been made in understanding the mechanisms of hemodynamic disturbances occurring in liver cirrhosis, which are based on portal hypertension. In addition to pathophysiological disorders related to endothelial dysfunction, it was revealed: There is the restructuring of the vasculature, which includes vascular remodeling and angiogenesis. In spite of the fact that these changes are the compensatory-adaptive response to the deteriorating conditions of blood circulation, taken together, they contribute to the development and progression of portal hypertension causing severe complications such as bleeding from esophageal varices. Disruption of systemic and organ hemodynamics and the formation of portosystemic collaterals in portal hypertension commence with neovascularization and splanchnic vasodilation due to the hypoxia of the small intestine mucosa. In this regard, the goal of comprehensive treatment may be to influence on the chemokines, proinflammatory cytokines, and angiogenic factors(vascular endothelial growth factor, placental growth factor, platelet-derived growth factor and others) that lead to the development of these disorders. This review is to describe the mechanisms of restructuring of the vascular bed in response to hemodynamic disturbances in portal hypertension. Development of pathogenetic methods, which allow correcting portal hypertension, will improve the efficiency of conservative therapy aimed at prevention and treatment of its inherent complications.

关键词： Portal hypertension Vascular remodeling Angiogenesis Pathogenesis liver cirrhosis