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New Orbital Parameters of 850 Wide Visual Binary Stars and Their Statistical Properties

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Research in Astronomy and Astrophysics 2025年第1期25卷 323-333页

作者： igor Izmailov Maxim Khovritchev Central Astronomical Observatory Russian Academy of Sciences

Based on positional observations and measurements of radial velocities,the orbits of 850 wide visual binary star have been *** parameters of the log-normal distributions for the histograms of orbital periods,stella masses,and semimajor axes in astronomical units have been *** eccentricity histogram for binary star with orbital periods less than 400 yr follows a normal distribution centered at e=0.545+/-*** stars with longer periods,this distribution obeys the law f=2e,with accuracy to *** mass-to-luminosity relation for stars with well-determined masses is given by:logL⊙=4.33 logM⊙-0.11,where L⊙and M⊙are th luminosity and mass of the star in units of the solar luminosity and mass,respectively.

关键词： (stars:) binaries: visual stars: fundamental parameters stars: statistics

Bile acid therapy for primary biliary cholangitis:Pathogenetic validation

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World Journal of Experimental Medicine 2025年第1期15卷 53-64页

作者： Vasiliy I Reshetnyak igor V Maev Department of Propaedeutics of Internal Diseases and Gastroenterology Russian University of MedicineMoscow 127473Russia

Knowledge of the etiological and pathogenetic mechanisms of the development of any disease is essential for its *** the cause of primary biliary cholangitis(PBC),a chronic,slowly progressive cholestatic liver disease,is still unknown,treatment remains *** of the physicochemical properties of various bile acids and the adaptive responses of cholangiocytes and hepatocytes to them has provided an important basis for the development of relatively effective drugs based on hydrophilic bile acids that can potentially slow the progression of the *** in the use of hydrophilic bile acids for the treatment of PBC are also associated with the discovery of pathogenetic mechanisms of the development of cholangiocyte damage and the appearance of the first signs of this *** 35 years,ursodeoxycholic acid(UDCA)has been the unique drug of choice for the treatment of patients with *** recent years,the list of hydrophilic bile acids used to treat cholestatic liver diseases,including PBC,has *** addition to UDCA,the use of obeticholic acid,tauroursodeoxycholic acid and norursodeoxycholic acid as drugs is *** pathogenetic rationale for treatment of PBC with various bile acid drugs is discussed in this *** is made on the mechanisms explaining the beneficial therapeutic effects and potential of each of the bile acid as a drug,based on the understanding of the pathogenesis of the initial stages of PBC.

关键词： Primary biliary cholangitis Treatment of primary biliary cholangitis with bile acids Ursodeoxycholic acid Obeticholic acid Tauroursodeoxycholic acid Norursodeoxycholic acid

秘鲁铜元素地球化学空间分布及对成矿远景区的预测

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地学前缘 2025年第1期32卷 205-218页

作者：胡庆海王学求张必敏迟清华王强孙彬彬周建王玮 igor ESPINOZA VERDE Alex AGURTO CORNEJO Joel OTERO AGUILAR 盘炜刘汉粮田密吴慧自然资源部地球化学探测重点实验室中国地质科学院地球物理地球化学勘查研究所河北廊坊065000 联合国教科文组织全球尺度地球化学国际研究中心河北廊坊065000 中国地质调查局发展研究中心北京100037 秘鲁能源矿业部地质矿产冶金研究院利马51

秘鲁位于南美洲西岸,作为安第斯成矿带的重要组成部分,矿产资源丰富,铜矿资源储量和产量位居世界第二。本文首次对秘鲁开展全国范围全球尺度地球化学调查工作,获得汇水域沉积物样品共416件,秘鲁全境铜元素含量为2.38~495μg/g,背景值(... 详细信息

秘鲁位于南美洲西岸,作为安第斯成矿带的重要组成部分,矿产资源丰富,铜矿资源储量和产量位居世界第二。本文首次对秘鲁开展全国范围全球尺度地球化学调查工作,获得汇水域沉积物样品共416件,秘鲁全境铜元素含量为2.38~495μg/g,背景值(中位数)为24.0μg/g。秘鲁全境、沿海带、安第斯山区和亚马孙平原的表层(深层)汇水域沉积物中铜元素平均含量依次为31.4(31.6)、45.6(32.2)、47.5(48.2)和21.3μg/g(24.9μg/g)。地球化学图显示,秘鲁铜空间分布整体呈现出西高东低的趋势,西部沿海带和中部安第斯山区含量较高,东部亚马孙平原区含量较低的特征。本文选用75%累积频率作为异常下限值,圈定出5处铜地球化学异常,其中两处达到地球化学巨省规模,两处达到地球化学域规模。同时,讨论铜地球化学异常的来源和影响因素,解析与之对应的矿产资源响应,秘鲁良好的构造演化环境,为大型、超大型铜矿床的形成提供有利条件。太平洋纳斯卡板块向南美大陆不断俯冲变换,致使洋壳发生部分熔融,产生强烈而广泛的中酸性岩浆活动,且岩浆中铜含量大规模富集,局部地区在特定环境下富集成矿。这一构造运动导致铜元素在秘鲁空间分布上呈现出多个地球化学块体,可能也是铜地球化学异常形成的原因之一。这些巨大的地球化学块体发现可用于未来寻找铜矿集区或大型、超大型铜矿床,圈定找矿远景区,并可以降低找矿风险,提高找矿效率,缩短找矿周期。研究圈定的地球化学找矿远景区,可为秘鲁铜矿勘查开发利用提供基础资料和数据。

关键词：秘鲁铜汇水域沉积物地球化学填图成矿远景区

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Four-wave mixing in a laser diode gain medium induced by the feedback from a high-Q microring resonator

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Photonics Research 2025年第1期13卷 59-68页

作者： DARIA M.SOKOL NIKITA yU DMITRIEV DMITRy A.CHERMOSHENTSEV SERGEy N.KOPTyAEV ANATOLy V.MASALOV VALERy E.LOBANOV igor A.BILENKO ARTEM E.SHITIKOV Russian Quantum Center Moscow Institute of Physics and Technology (MIPT) Skolkovo Institute of Science and Technology Lebedev Physical Institute Russian Academy of Sciences Faculty of Physics M.V.Lomonosov Moscow State University

Laser diodes are widely used and play a crucial role in myriad modern applications including nonlinear optics and ***,we explore the four-wave mixing effect in a laser diode gain medium induced by the feedback from the high-Q microring *** phenomenon can be observed at a laser frequency scan close to the microresonator eigenfrequency,prior to the transition of the laser diode from a free-running to a self-injection locking *** effect opens up the possibility for generation of remarkably low-noise,stable,and adjustable microwave *** provide a detailed numerical study of this phenomenon proven with experimental results and demonstrate the generation of the signals in the GHz *** obtained results reveal the stability of such regime and disclose the parameter ranges enabling to achieve ***,our findings uncover,to our knowledge,a novel laser diode operation regime and pave the way for the creation of new types of chip-scale,low-noise microwave sources,which are highly demanded for diverse applications,including telecommunication,metrology,and sensing.

关键词： Four wave mixing

Risk Assessment of a Stochastic Service System

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Journal of Systems Science and Systems Engineering 2020年第5期29卷 537-554页

作者： igor Lazov Faculty of Informatics European University Skopje1000 SkopjeMacedonia

A stochastic service system of finite size M is comprised of identical service facilities,including or not a waiting queue,which simultaneously treats N customers,N∈{0,1,…,M}.Depending on the concepts of system information *** system entropy S=£(f),we promote a risk assessment *** definition,the system entropy is the uncertainty associated with the system,and the system expected loss is the risk associated with the ***,accepting the system information as loss function,we can identify risk and uncertainty,associated with the system,using the entropy as risk ***,we differ risk of the system(i.e.,risk observed by an outside observer),risk observed by an arriving customer,and risk observed by a departing customer,giving a separate expression for each ***,these risks are compared with each other,when the system has the same average number E(N)of customers seen by any *** three risk types(together with the three customer means)allow us to distinguish two systems obeying the same probability *** approach enables system operators to choose suitable values for system utilization and size,in view of the three risks *** developed procedure is applied to the information linear system,Erlang loss system,single-server queueing system with discouraged arrivals,Binomial system and Engset loss system.

关键词： Absolute and relative risk uncertainty system information and entropy system utilization stochastic service system

The Functional Role of the Hollow Region of the Butterfly Pyrameis atalanta (L.) Scale

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Journal of Bionic Engineering 2008年第3期5卷 224-230页

作者： igor Kovalev Kinneret College on the Sea of Galilee Emek Hayarden 15132 Israel

Questions concerning the functional role of the hollow region of the butterfly Pyrameis atalanta （L.） scale are experimentally investigated. Attention was initially directed to this problem by observation of the complex microstrucmre of the butterfly scale as well as other studies indicating higher lift on butterfly wings covered with scale. The aerodynamic forces were measured for two oscillating scale models. Results indicated that the air cavity of an oscillating model of the Pyrameis atalanta （L.） scale increased the lift by a factor of 1.15 and reduced the damping coefficients by a factor of 1.38. The modification of the aerodynamic effects on the model of butterfly scale was due to an increase of the virtual air mass, which influenced the body. The hollow region of the scale increased the virtual air mass by a factor of 1.2. The virtual mass of the butterfly scale with the hollow region was represented as the sum of air mass of two imaginary geometrical figures： a circular cylinder around the scale and a right-angled parallelepiped within the hollow region. The interaction mechanism of the butterfly Pyrameis atalanta （L.） scale with a flow was described. This novel interaction mechanism explained most geometrical features of the airpermeable butterfly scale （inverted V-profile of the ridges, nozzle of the tip edge, hollow region, and openings of the upper lamina） and their arrangement.

关键词： bionic butterfly scale hollow region damped coefficient flapping motion virtual mass

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Use of GIS technology and cellular automata for modeling multiple socio-economic scenarios of regional spatial development and inter-regional cooperation

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Geo-Spatial Information Science 2023年第1期26卷 71-93页

作者： igor Musikhin Alexander Karpik Department of Photogrammetry and Remote Sensing Siberian State University of Geosystems and TechnologiesNovosibirskRussia Department of Space and Physical Geodesy Siberian State University of Geosystems and TechnologiesNovosibirskRussia

The advancement of effective spatial planning to support sustainable development and interregional cooperation has become an issue of serious concern for regional *** planning research helps to identify economic clusters and analyze their changing spatial patterns,which is important for understanding regional economic space dynamics and poten-tial inter-regional *** support decision-makers in the development of efficient plans of spatial development encompassing the identification of the best-suited territories,a combined Geographic Information System(GIS)based approach to interpret qualitatively expressed multiple socio-economic scenarios in quantitative map-based terms of graded suitability,and a formalized approach to the socio-economic evaluation of the territory is *** on GIS technology coupled with integrated cellular automata decision analysis techniques,the study provides a method that performs socio-economic assessment of the study area according to the generated scenarios of regional spatial and socio-economic *** proposed method is applied to Primorsky and Khabarovsk Krais,located in the Russian Far ***-economic scenarios of spatial development initiated by investors and regional authorities were assessed and *** generated socio-economic scenar-ios illustrate how the unified set of spatial and socio-economic variables can be linked and used to gain insights into inter-regional socio-economic and spatial *** application results demonstrate the advantage of the proposed method in identifying the best-suited unit areas for targeted regional development.

关键词： Geographic Information System(GIS) spatial development socioeconomic scenarios interregional cooperation open source software Cellular Automata(CA)

Uncertainty in satellite remote sensing of snow fraction for water resources management

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Frontiers of Earth Science 2018年第4期12卷 711-727页

作者： igor APPEL TAG LLC WashingtonDistrict of Columbia20024USA

Snow fraction is an important component of land surface models and hydrologic models. Information on snow fraction also improves downstream products retrieved from remote sensing: vertical atmosphere profiles, soil moisture, heat fluxes, etc. The uncertainty of the fractional snow cover estimates must be determined, quantified, and reported to consider the suitability of the product for modeling, data assimilation and other applications. The reflectances of snow and non-snow are characterized by a very significant local variability and also by changes from one scene to another. The local snow and non-snow endmembers are approximated by the Normalized Difference Snow Index with a high accuracy. The magnitudes of snow and non-snow Normalized Difference Snow Indexes are scene-specific and calculated on the fly to retrieve snow fraction. The development of the Normalized Difference Snow Index based algorithms to estimate snow fraction including a scene-specific approach taking local snow and non-snow properties into account is considered an optimal way to fractional snow retrieval from moderate resolution optical remote sensing observations. The Landsat reference data are used to estimate the performance of the fractional snow cover algorithms at moderate resolution and to compare the quality of alternative algorithms. The validation results demonstrate that the performance of the algorithms using Normalized Difference Snow Index has advantages. The advantages achieved in snow fraction retrieval lead to improved estimate of snow water equivalent and changes in snow cover state contributing to better modeling of land surface and hydrologic regime. The success of managing water resources on the whole depends on coordinating described investigations with the works of other researchers developing further enhanced models.

关键词： algorithm remote sensing uncertainty validation snow cover fraction

A NUMERICAL METHOD FOR SOLVING NONLINEAR INTEGRO-DIFFERENTIAL EQUATIONS OF FREDHOLM TyPE

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Journal of Computational Mathematics 2016年第3期34卷 262-284页

作者： igor Boglaev Institute of Fundamental Sciences Massey UniversityPrivate Bag 11-222 Palmerston North New Zealand

The paper deals with a numerical method for solving nonlinear integro-parabolic prob- lems of Fredholm type. A monotone iterative method, based on the method of upper and lower solutions, is constructed. This iterative method yields two sequences which converge monotonically from above and below, respectively, to a solution of a nonlinear difference scheme. This monotone convergence leads to an existence-uniqueness theorem. An analy- sis of convergence rates of the monotone iterative method is given. Some basic techniques for construction of initial upper and lower solutions are given, and numerical experiments with two test problems are presented.

关键词： Nonlinear integro-parabolic equations of Fredholm type Nonlinear differenceschemes Monotone iterative methods The method of upper and lower solutions.