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Orbits of 152 globular clusters of the Milky Way galaxy constructed from Gaia DR2

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Research in Astronomy and Astrophysics 2021年第7期21卷 177-191页

作者： Anisa Talgatovna Bajkova vadim vadimovich Bobylev Pulkovo Astronomical Observatory St.Petersburg 196140Russia

We present orbits and their properties for 152 globular clusters of the Milky Way galaxy obtained using average Gaia DR2 proper motions and other astrometric data from the list of Vasiliev. For orbital integration we have applied the axisymmetric model of the Galactic potential based on the Navarro-Frenk-White dark halo, and modified by Bajkova & Bobylev utilizing circular velocities of Galactic objects in a wide region of Galactocentric distances(up to 200 kpc) from the Bhattacharjee et al. catalog. Based on the analysis of the obtained orbits, we have modified the composition of the subsystems of globular clusters presented in Massari et al..

关键词： (Galaxy) globular clusters general

A Numerical Analysis of Turbulent Compressible Radial Channel Flow with Particular Reference to Pneumatic Controllers

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Journal of Thermal Science 2004年第1期13卷 24-29页

作者： Gilles Roy Dinh Vo-Ngoc vadim Bravine Faculty of Engineering Université de MonctonMonctonNBCanadaE1A 3E9Faculty of EngineeringUniversité de MonctonMonctonNBCanadaE1A 3E9Faculty of EngineeringUniversité de MonctonMonctonNBCanadaE1A 3E9

A numerical analysis of turbulent axisymmetric radial compressible channel flow between a nozzle and a flat plate is presented in this paper. In particular, the application of this type of flow situation in pneumatic dimensional control systems is considered. The Spalart-Allmaras one-equation turbulence model is used. The resulting highly coupled PDE system has been solved using the control volume based numerical approach where the power-law scheme was used extensively to compute the diffusive and convective fluxes of momentum. Results show that local Mach numbers can easily achieve and surpass unity for typical industrial configurations. Also, in the case of a standard industrial nozzle geometry, the presence of a toroidal recirculation zone that moves radially outward is clearly identified in most cases. Separated flow areas are of particular concern as it has been shown previously that they can cause nozzle fouling in industrial applications. It has been shown that the size of this region is dependant on feed pressure. Considerable differences between results obtained using the Spalart-Allmaras and standard k- εturbulence models have also been noticed.

关键词： compressible radial flow numerical simulation pneumatic controllers impinging jet with confinement.

Analysis of the Quantity and Causes of Outages in LV/MV Electric Grids

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 537-542页

作者： Alexander Vinogradov Alina Vinogradova vadim Bolshev Laboratory of power supply and electrical safety Federal Scientific Agroengineering Center VIMMoscow109428 Russia

The paper considers the quantity and causes of outages in electric grids of low and medium voltages using the example of an electric grid of a regional power supply company.The main types of damage to the equipment of power lines and transformer substations were identified.Data on other areas of rural and urban electric grids are also analyzed.The main directions for reducing the quantity of outages in electric grids are proposed based on this analysis.Among them,there are the use of isolated wires in power transmission lines,the improvement of design of switching devices,switches and terminals of transformers,the application of technical condition diagnostics,the disaggregating of power lines and the increase of protection sensitivity of power lines.Most of the causes of equipment damage can be prevented by increasing the maintenance level of this equipment.

关键词： Electrical network grid power line power outages power supply reliability PTL transformer

A Markov chain model of mixing kinetics for ternary mixture of dissimilar particulate solids

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Particuology 2017年第2期15卷 80-86页

作者： vadim Mizonov Ivan Balagurov Henri Berthiaux Cendrine Gatumel Department of Applied Mathematics Ivanovo State Power Engineering University Russia Centre RAPSODEE UMR CNRS 5302 Ecole des Mines d'Albi-Carmaux Campus Jarlard Route de Teillet 81000 Alhi France

This paper presents a simple but informative mathematical model to describe the mixing of three dissimilar components of particulate solids that have the tendency to segregate within one another. A nonlinear Markov chain model is proposed to describe the process. At each time step, the exchange of particulate solids between the cells of the chain is divided into two virtual stages. The first is pure stochastic mixing accompanied by downward segregation. Upon the completion of this stage, some of the cells appear to be overfilled with the mixture, while others appear to have a void space. The second stage is related to upward segregation. Components from the overfilled cells fill the upper cells （those with the void space） according to the proposed algorithm. The degree of non-homogeneity in the mixture （the standard deviation） is calculated at each time step, which allows the mixing kinetics to be described. The optimum mixing time is found to provide the maximum homogeneity in the ternary mixture. However, this “common” time differs from the optimum mixing times for individual components. The model is verified using a lab-scale vibration vessel, and a reasonable correlation between the calculated and experimental data is obtained

关键词： Ternary mixture Segregation Mixing kinetics Markov chain Matrix of transition probabilities Optimum mixing time

Cell models with inducible oncogenic translocations allow to evaluate the potential of drugs to favor secondary translocations

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Cancer Communications 2023年第1期43卷 154-158页

作者： Anna Shmakova Nikolai Lomov Vladimir Viushkov Tatyana Tsfasman Yana Kozhevnikova Darina Sokolova vadim Pokrovsky Marina Syrkina Diego Germini Mikhail Rubtsov Yegor Vassetzky UMR9018 UniversitéParis-SaclayCentre national de la recherche scientifiqueGustave RoussyVillejuif 94805France Koltzov Institute of Developmental Biology Russian Academy of SciencesMoscow 119334Russia Department of Molecular Biology Faculty of BiologyLomonosov Moscow State UniversityLeninskie GoryMoscow 119991Russia Institute of Experimental Cardiology National Medical Research Centre of CardiologyMoscow 121552Russia Faculty of Medicine Lomonosov Moscow State UniversityMoscow 119991Russia Laboratory of Combined Treatment Blokhin Cancer Research CenterMoscow 115478Russia Department of Biochemistry Peoples’Friendship University of RussiaMoscow 117198Russia Center of Genetics and Life Sciences Sirius University of Science and TechnologyFederal Territory SiriusSochi 354340Russia Department of Biochemistry Center for Industrial Technologies and EntrepreneurshipSechenov First Moscow State Medical UniversityMoscow 119991Russia

Dear Editor,Chromosomal translocations result from the interchange of geneticmaterial between non-homologous chromosomes.Chromosomal translocations are formed by erroneous repair of double-stranded breaks(DSBs)via non-homologous end joining(NHEJ)[1].Some genotoxic drugs produce DSBs and thus present a major risk factor for the development of oncogenic chromosomal translocations.The risk factors that interfere with translocationprone DSB repair,once DSBs are already formed,are obscure,and potential effects of drugs on translocation formation during this step have never been explored.

关键词： drugs potential chromosomal

Propulsion Challenges for Small Spacecraft: 2005

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Tsinghua Science and Technology 2006年第5期11卷 507-514页

作者： vadim Zakirov 李路明 Tsinghua Space Center School of Aerospace Tsinghua University

Small （〈100 kg） spacecrafts are being developed in many countries but their propulsion systems still have many challenges. Although there is demand for small spacecraft propulsion, the number of missions at present is small due to several commercial and technical reasons. Poor performance of existing small spacecraft propulsion systems is one of the main reasons for the small number of missions. Several reasons are given for the poor performance of existing small spacecraft propulsion. Suggested improvements focus on small spacecraft and propulsion hardware mass optimization rather than on specific impulse enhancement. Propellantless propulsion systems are also recommended for small spacecraft interplanetary missions.

关键词： propulsion small spacecraft performance enhancement payload

Russian Nuclear Rocket Engine Design for Mars Exploration

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Tsinghua Science and Technology 2007年第3期12卷 256-260页

作者： vadim Zakirov Vladimir Pavshook Tsinghua Space Center School of AerospaceTsinghua University Russian Research Center "Kurchatov Institute" Kurchatov Sq.1Moscow 123182Russia

This paper is to promote investigation into the nuclear rocket engine （NRE） propulsion option that is considered as a key technology for manned Mars exploration. Russian NRE developed since the 1950s in the former Soviet Union to a full-scale prototype by the 1990s is viewed as advantageous and the most suitable starting point concept for manned Mars mission application study. The main features of Russian heterogeneous core NRE design are described and the most valuable experimental performance results are summarized. These results have demonstrated the significant specific impulse performance advantage of the NRE over conventional liquid rocket engine （LRE） propulsion technologies. Based on past experience, the recent developments in the field of high-temperature nuclear fuels, and the latest conceptual studies, the developed NRE concept is suggested to be upgraded to the nuclear power and propulsion system （NPPS）, more suitable for future manned Mars missions. Although the NRE still needs development for space application, the problems are solvable with additional effort and funding.

关键词： nuclear rocket engine Mars exploration propulsion technology design

The impact of anti-epidemic measures against coronavirus disease 2019 (COVID-19) on the seasonal influenza epidemic

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Chinese Medical Journal 2021年第7期134卷 879-880页

作者： Tatyana N.Ilyicheva vadim NGureyev Vector State Research Center of Virology and Biotechnology Koltsovo 630559Russia Department of Natural Sciences Novosibirsk State UniversityNovosibirsk 630090Russia.

To the Editor:A new type of coronavirus—severe acute respiratory syndrome coronavirus 2 causing coronavirus disease 2019(COVID-19)emerged in 2019.[1]On March 11,2020,World Health Organization(WHO)Director-General declared that the outbreak can be characterized as a pandemic.[2]According to the WHO,[3]on March 18,2020,the number of laboratory-confirmed cases of COVID-19 was over 200 thousands worldwide.In some countries,unprecedented anti-epidemic measures have been carried out to stop the spread of infection.

关键词： epidemic acute measures

Advances in the development of new biomarkers for Alzheimer’s disease

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Translational Neurodegeneration 2022年第1期11卷 601-624页

作者： Timofey O.Klyucherev Pawel Olszewski Alena A.Shalimova Vladimir N.Chubarev vadim V.Tarasov Misty M.Attwood Stina Syvänen Helgi B.Schiöth Department of Neuroscience Functional PharmacologyUniversity of Upp-salaUppsalaSweden Department of Pharmacology Institute of PharmacyI.M.Sechenov First Moscow State Medical UniversityMoscowRussia Institute of Translational Medicine and Biotechnology I.M.Sechenov First Moscow State Medical UniversityMoscowRussia Department of Public Health and Caring Sciences Rudbeck LaboratoryUppsala UniversityUppsalaSweden.

Alzheimer’s disease(AD)is a complex,heterogeneous,progressive disease and is the most common type of neurodegenerative dementia.The prevalence of AD is expected to increase as the population ages,placing an additional burden on national healthcare systems.There is a large need for new diagnostic tests that can detect AD at an early stage with high specificity at relatively low cost.The development of modern analytical diagnostic tools has made it possible to determine several biomarkers of AD with high specificity,including pathogenic proteins,markers of synaptic dysfunction,and markers of inflammation in the blood.There is a considerable potential in using microRNA(miRNA)as markers of AD,and diagnostic studies based on miRNA panels suggest that AD could potentially be determined with high accuracy for individual patients.Studies of the retina with improved methods of visualization of the fundus are also showing promising results for the potential diagnosis of the disease.This review focuses on the recent developments of blood,plasma,and ocular biomarkers for the diagnosis of AD.

关键词： Alzheimer’s disease Amyloid beta peptides Biomarkers Blood Cytokines Inflammation MicroRNA Ocular biomarkers