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Insulator-to-conductor transition driven by the Rashba–Zeeman effect

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npj Computational Materials 2020年第1期6卷 247-253页

作者： Lingling Tao evgeny Y.Tsymbal Department of Physics and Astronomy&Nebraska Center for Materials and Nanoscience University of NebraskaLincolnNE 68588USA

The Rashba effect has recently attracted great attention owing to emerging physical properties associated with *** interplay between the Rashba effect and the Zeeman effect,being produced by the exchange field,is expected to broaden the range of these properties and even result in novel *** we predict an insulator-to-conductor transition driven by the Rashba–Zeeman *** first illustrate this effect using a general Hamiltonian model and show that the insulator-to-conductor transition can be triggered under certain Rashba and exchange-field strengths.

关键词： effect Zeeman conductor

Tracking facial features with occlusions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1282-1288页

作者： MARKIN evgeny PRAKASH Edmond C. School of Computer Engineering Nanyang Technological University Singapore

Facial expression recognition consists of determining what kind of emotional content is presented in a human face. The problem presents a complex area for exploration, since it encompasses face acquisition, facial feature tracking, facial ex- pression classification. Facial feature tracking is of the most interest. Active Appearance Model (AAM) enables accurate tracking of facial features in real-time, but lacks occlusions and self-occlusions. In this paper we propose a solution to improve the accuracy of fitting technique. The idea is to include occluded images into AAM training data. We demonstrate the results by running ex- periments using gradient descent algorithm for fitting the AAM. Our experiments show that using fitting algorithm with occluded training data improves the fitting quality of the algorithm.

关键词： Active Appearance Model (AAM) Facial feature tracking Computer vision

Uncertainty in measurements of the distances of scattering screens in pulsar observations

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Research in Astronomy and Astrophysics 2018年第8期18卷 117-120页

作者： evgeny N.Fadeev Lebedev Physical Institute Astro Space Center

In our previous paper we investigated properties of the ionized interstellar medium in the direction of three distant pulsars; B1641-45, B1749-28 and B1933＋16. We found that uniformly dis- tributed scattering material cannot explain measured temporal and angular broadening. We applied a model for a thin scattering screen and found the distances to the scattering screens in all directions. In this paper, we consider more complicated models of scattering material distribution, such as models containing both a uniformly distributed medium and thin screen. Based on these models, we estimate the accuracy of localization of scattering screens and the possible relative contribution of each scattering component.

关键词： ISM structure - pulsars general - scattering

The prognostic role of high-sensitivity C-reactive protein in patients with acute myocardial infarction

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Journal of Geriatric Cardiology 2020年第7期17卷 379-383页

作者： Ekaterina A Polyakova evgeny N Mikhaylov Department of Faculty Therapy Pavlov First Saint-Petersburg State Medical UniversitySaint-PetersburgRussian Federation Metabolic Syndrome Laboratory Institute of EndocrinologyAlmazov National Medical Research CentreSaint-PetersburgRussian Federation Neuromodulation Lab and Arrhythmia Department Almazov National Medical Research CentreSaint PetersburgRussian Federation Department of Bioengineering Systems Saint-Petersburg Electrotechnical University“LETI”Saint PetersburgRussian Federation

1 Introduction Inflammation is one of the main mechanisms in the pathogenesis of atherosclerosis,and the interest to the evaluation of inflammatory biomarkers in coronary artery disease(CAD)has been increasing over the last decade.[1,2]Destabilization of chronic artery plaques,which leads to acute coronary syndromes,has been associated with inflammatory status.[1,3]。

关键词： Atrial fibrillation Coronary artery disease High sensitive C-reactive protein Myocardial infarction Prognosis

Migration of organic carbon and trace elements in the system glacier-soil in the Central Caucasus alpine environment

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Journal of Mountain Science 2022年第12期19卷 3458-3474页

作者： Ivan KUSHNOV evgeny ABAKUMOV Rustam TEMBOTOV Timur NIZAMUTDINOV Saint Petersburg State University 7/9 University EmbankmentSt Petersburg199034Russia Tembotov Institute of Ecology of Mountain Territories of Russian Academy of Sciences 7a I.Armand StreetNalchik360051Russia

Rapid deglaciation is one of the most important challenges in the Earth science *** reason of this is specific supraglacial sediments–cryoconites,which represent carbon-containing dust with organomineral matter and living *** of physical and chemical characteristics of cryoconites in the Central Caucasus is necessary in order to understand their influence on alpine territories biogeochemical cycles,pollution and development in conditions of intensive glacial melting and active anthropogenic *** this research cryoconites as well as moraines,soil-like bodies and soils have been sampled from the alpine Bezengi Glacier and adjacent Khulamo-Bezengi *** physicochemical features(pH values,total organic carbon content,microbial respiration,particle-size distribution)as well as content of trace elements have been defined in sampled materials and several pollution indices(Geoaccumulation index,Contamination factor and Degree of pollution)have been *** obtained show low values of total organic carbon in cryoconites(max.0.23%)but high values(max.7.54%)in top horizon of soils located in floodplain,indicating its active fluvioglacial transfer which may further accelerate the development of *** activity in the studied soils was mostly influenced by additional input of labile organic carbon from cryoconites with water ***-size distribution was similar among the studied cryoconites,indicating dominance of sand fraction(up to 85.28%)while studied soils showed higher variability due to influence of *** the trace elements,cryoconites were mostly polluted by Zn(max.85.70 mg·kg^(-1))which corresponds to high pollution according to pollution indices;Pb(max.24.90 mg·kg^(-1))and Cu(max.17.40 mg·kg^(-1)),up to moderate pollution *** of polluted cryoconite material as well as local anthropogenic activities increased pollution of periglacial soils by Zn(max.89.20 mg·kg^(-1)),Pb(m

关键词： Cryoconites Umbrisols Leptosols Pollution Caucasus mountain range

Sediments from cryoconite holes and dirt cones on the surface of Svalbard glaciers:main chemical and physicochemical properties

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Acta Geochimica 2023年第2期42卷 346-359页

作者： Timur Nizamutdinov Bulat Mavlyudov Vyacheslav Polyakov evgeny Abakumov Department of Applied Ecology Faculty of BiologySt.Petersburg State University16th Liniya V.O.29St.PetersburgRussia 199178 Russian Academy of Sciences Institute of GeographyMoscowRussia 119017

The paper discussed the influence of the forms of sediment accumulation on the surface of glaciers on their chemical and physicochemical *** materials sampled from the surface of five glaciers of the Svalbard Archipelago was *** studied such forms of sediment accumulation as dirt cones-the ice core covered with sediments and cryoconite holes-hollows on the glacier surface containing cryoconite *** such as total organic carbon content,microbiological activity,pH,the content of mobile forms of potassium and phosphorus,and concentrations of heavy and trace metals were ***,mesomorphological studies were carried out and the polydisperse composition of the sediments was *** to the results of this work,it was found that the content of organic carbon in the material selected from dirt cones and cryoconite holes can be up to 2.5%,but the content of clay particles in it is mainly at the 10–15%*** concentrations are up to 250 mg/kg,and phosphorus is up to 800 mg/*** content of metals is typical or lower than in the previously published *** main influence on the chemical composition of materials has a geographical factor of the sampling site,rather than the form of material accumulation.

关键词： Arctic Soil-like bodies Glacier sediments Accumulation

Features of the long-term transformation of the Krasnodar reservoir,near the mouth of the Kuban River,Russia

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Journal of Geographical Sciences 2021年第12期31卷 1895-1904页

作者： POGORELOV Anatoly LAGUTA Andrey KISELEV evgeny LIPILIN Dmitry Kuban State University Krasnodar 350040Russia Aerogematica LLC Krasnodar 350063Russia Kuban State Agrarian University Named after I.T.Trubilin Krasnodar 350044Russia Tuapse Branch of the Russian State Hydrometeorological University Krasnodar RegionTuapse 352800Russia

The article considers the long-term(1941-2018)transformation of the Krasnodar valley reservoir,the largest in the North *** main functions of the Krasnodar reservoir are irrigation of rice systems and flood protection of land in the Krasnodar reservoir region and the Republic of *** to topographic maps,Landsat satellite images(1974-2018)and field observations(2016-2018),four stages of transformation of the floodplain reservoir are *** selected stages are characterized by both natural causes(the transformation of the filling deltas into the extended deltas,etc.)and man-made causes(runoff diversions in the delta areas,etc.).The key factor of transformation is the formation of deltas of rivers flowing into the *** of the selected stages,against the background of a gradual reduction in the area and volume of the reservoir,is characterized by the peculiarities of the formation of river deltas with the formation of genetically homogeneous sections of delta *** the period of operation of the reservoir,the delta of the main Kuban River moved up to 32.4 km and took away an area of 35.4 km^(2) of the *** the formation of the deltas of the Kuban and Belaya rivers,a bridge was formed on the Krasnodar *** evolution of the delta regions led to the division of the reservoir into two autonomous *** total area of the delta regions was 85.9 km^(2) by 2018,i.e.,21% of the initial area of the *** transformation of the Krasnodar reservoir leads to a decrease in its regulated volume and gradual degradation.

关键词： Krasnodar reservoir sedimentation siltation transformation delta formation Landsat

Geochemistry of cryoconite and soils in the Central Caucasus region and its environmental implications

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Journal of Mountain Science 2021年第12期18卷 3109-3124页

作者： Ivan KUSHNOV evgeny ABAKUMOV Rustam TEMBOTOV Vyacheslav POLYAKOV Saint Petersburg State University 7/9 University EmbankmentSt Petersburg 199034Russian Federation Tembotov Institute of Ecology of Mountain Territories Russian Academy of Sciences37-a I.Armand Str.Nalchik360051Russian Federation

Climate change and deglaciation are active processes in current changing *** the Central Caucasus region rapid degradation of glaciers is caused often by the formation of superficial blackcolored *** plays a crucial role in changing ecosystems and may contribute to the formation of primary soils after glacier *** the past 20 years,the frequency of mudflows and other dangerous mountain events have increased in the Central Caucasus,which is associated with the glacial *** of tourism results in increasing of traffic,recreational activity and environment *** of the cryoconites geochemical properties in comparison with other types of sediments and local soils is crucial for investigation of geochemistry and contamination state of superficial glacial *** environmental aspect is important in terms of the Central Caucasus settlements safety under conditions of deglaciation and anthropogenic *** sediments studied(cryoconite,mudflow,moraine)were sampled at Garabashi and Skhelda glaciers as well as some local soils at the Baksan *** materials were investigated in terms of physicochemical and agrochemical *** concentrations of trace elements(Cu,Pb,Zn,Ni,Cd)were also determined and contamination indices(geoaccumulation index-Igeo,contamination factor-CF and degree of contamination-Cdegree)were used to evaluate the pollution status of studied *** obtained shows much higher content of organic carbon in soils(up to 7.82%)in comparison with cryoconite(max.1.63%)due to presence of vegetation,however,the basal respiration values in some cases were similar betweenсryoconite and soils,indicating high rates of microbial activity in a cryoconite *** was found that almost all materials studied have sandy *** sediments on both of the glaciers are enriched with phosphorus,high values of K_(2)O(max.298 mg·kg^(-1))and N-NH4(max.

关键词： Cryoconite Trace elements Entisols Contamination Central Caucasus

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