Известия Коми научного центра УрО РАН @izvestia-komisc
Статьи журнала - Известия Коми научного центра УрО РАН
Все статьи: 1211
Статья научная
Резюме: MTOR - механическая мишень рапамицина. Путь mTOR имеет множество механизмов регуляции: гуморальный, энергетическим статусом, цитокинами и сигнальными путями MAPK. mTOR участвует в синтезе белка, в обмене глюкозы, инсулина и липидов, в метаболизме глутамина. Является важным регулятором множества неврологических и иммунных процессов. Передача сигналов mTOR вовлечена в процесс старения, в инициацию развития многих видов опухолевого роста.
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Maxwell equations in Lobachevsky space and modeling the medium with reflecting properties
Статья научная
Lobachevsky geometry simulates a medium with special constitutive relations Di = ϵ0ϵikEk, Bi = μ0μikHk, where two matrices coincide: ϵik(x) = μik(x). The situation is specified in quasi-Cartesian coordinates (x, y, z) in Lobachevsky space, they are appropriate for modeling a medium nonuniform along the axis z. Exact solutions of the Maxwell equations in complex form of Majorana-Oppenheimer have been constructed. The problem reduces to a second-order differential equation for a certain primary function which can be associated with the one-dimensional Schrödinger problem for a particle in external potential field U(z) = U0e2z. In the frames of the quantum mechanics, Lobachevsky geometry acts as an effective potential barrier with reflection coefficient R = 1; in electrodynamic context, this geometry simulates a medium that effectively acts as an ideal mirror distributed in space. Penetration of the electromagnetic field into the effective medium along the axis z depends on the parameters of an electromagnetic waves ω, k2 1 + k2 2 and the curvature radius ρ of the used Lobachevsky model. The generalized quasi-plane wave solutions f(t, x, y, z) = E + iB and the relevant system of equations are transformed into the real form, which permit us to relate geometry characteristics with expressions for effective tensors of electric and magnetic permittivities.
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Migrations of the long-tailed duck in the European North-East of Russia
Статья научная
Arctic Russia is home to more than 90 % of all Long-tailed Ducks in the Clangula hyemalis species from the Western Siberia/Northern Europe population. The main wintering grounds of Long-tailed Ducks are situated in the Baltic Sea. The principal migratory routes of the Long-tailed Duck between the breeding and wintering grounds are relatively well-studied and follow the so-called Norwegian route along the Barents Sea coastline via the Pomorskij Strait, over the Kolguyev Island, the Kaninskij Peninsula and the White Sea. The secondary migration routes are still understudied. It has been determined that a portion of the population regularly migrates through the eastern part of Ukraine and European Russia, including the Komi Republic, the Kirov Region, the Nizhny Novgorod and Perm Regions, and the Republics of Udmurtia, Mari El, and Bashkortostan. Thus, a portion of the population utilises the «Volga-Caspian» migration route. This migration route is not as massive and covers a broad area. Long-tailed Ducks migrate in flocks of 4 to 56 individuals. Sometimes, there may be a higher intensity of migration. It is highly likely that the wintering grounds of these birds are located in the Caspian and Black Seas, where 4-5 thousand Long-tailed Ducks were counted within a relatively small area. A detailed study of all relevant ecological aspects is needed to contribute to the conservation of the Long-tailed Duck.
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Статья научная
he efficiency of application of cationic polyacrylamide and its hydrophobized derivative at the stage of cell biomass separation from the cell cultures fluid is estimated. Cells of oil-degrading microorganisms obtained from mixed culture fluid by flocculation and flotation retain their viability for further use in the treatment of oil-contaminated soils under non-sterile conditions. The application of a new form of oil-oxidizing preparation resulted in a 40 % reduction of total petroleum hydrocarbon content in the contaminated soil.
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NEXAFS и XPS исследования пористого кремния
Статья научная
Методами ультрамягкой рентгеновской спектроскопии с применением синхротронного излучения исследованы пористые слои кремния с различными типами проводимости. Определена эффективная толщина оксида на поверхности кремниевого скелетона и изучена структура интерфейса на границе кремний/оксид кремния. Показано, что тонкая структура спектров поглощения Si 2p кремниевого скелета совпадает с тонкой структурой спектра кристаллического кремния, а толщина оксидного слоя на поверхности пористого кремния 1,8-2,4 нм для различных образцов. Параметр x в стехиометрической формуле SiOх оксида кремния находится в диапазоне 1,66-1,82.
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O словесном ударении в нижнечепецком диалекте удмуртского языка
Статья научная
В статье проводится последовательное сравнение языковых фактов нижнечепецких говоров с аналогичными явлениями северных диалектов и других удмуртских говоров. Показано, что ведущие особенности словесной акцентуации нижнечепецкого диалекта наиболее сближают его со среднечепецкими говорами северноудмуртского наречия.
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Статья научная
The classical and quantum problems of motion of two particles in a three-dimensional Lobachevsky space is formulated with respect to center of mass with arbitrary position. The Hamilton-Jacobi and Schrödinger equations of the problem are formulated and their solutions are found. It is shown that the reduced mass of the system depends on the relative distance. The classical and quantum problems of a rigid rotator in three-dimensional sphere and Lobachevsky space are formulated and solved. The dependences of the oscillation periods of the rotator on the ratio of the masses of the particles forming it are studied for a fixed total mass in the cases of spaces of constant curvature.
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On the moss flora of the Yugyd va national park (Malyi Patok river basin, Subpolar Urals)
Статья научная
An annotated list of mosses from the basin of the Malyi Patok River (Yugyd Va National park, Subpolar Urals) is presented. It includes 80 species from 43 genera and 22 families. Data on habitats of the mosses and brief description of natural conditions and main types of vegetation are given. The following rare and protected in the Komi Republic species are registered: Ochyraea norvegica (Bruch et al.) Ignatov et Ignatova, Pohlia ludwigii (Spreng. ex Schwägr.) Broth. and Polytrichastrum sexangulare (Floerke ex Brid.) G. L. Sm.
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On the role of atmospheric methane in the Earth's global climate
Краткое сообщение
The contribution of atmospheric methane in global warming of the Earth is considered. Atmospheric emission of CH4 in Russia is based on three types of production: energy, agriculture and processing of industrial and household waste. Data on anthropogenic methane emissions into the atmosphere from Russian sources are given. Economic features of the Russian Arctic methane and economic benefits in the development of the region and additional threats to its environment and climate are provided.
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Population migration in the Russian Far East in the 1860s
Статья научная
Demographic studies can be categorized on the basis of demographic variables into studies of fertility, mortality, population migration, population structure, population distribution, population quality, and marriage and family in demography, while migration, along with births and deaths, determines the size of the population and its growth rate in the region, as well as determining the demographic characteristics of the region. The most important demographic problem of the Russian Far East is migration, which consists in the movement of people from the countryside to the towns, from one region of the country to another, from one’s own country to another. The past era could well be called the ‘age of migration’. Migration is often the result of economic and social development, which can contribute to the improvement of economic and social conditions or, on the contrary, lead to economic stagnation and social imbalances.
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Potentials allowing integration of the perturbed two-body problem in regular coordinates
Статья научная
The problem of separation of variables in some coordinate systems obtained with the use of L-transformations is studied. Potentials are shown that allowseparation of regular variables in a perturbed two-body problem. The potential contains two arbitrarysmooth functions. An example of a potential is considered allowing explicit solution of the problem interms of elliptic functions. The cases of boundedand unbounded motion are shown. The results ofnumerical experiments are given.
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Remark on continued fractions, Mobius transformations and cycles
Статья научная
We review interrelations between continued fractions, Mobius transformations and representations of cycles by 2 x 2 matrices. This leads us to several descriptions of continued fractions through chains of orthogonal or touching horocycles. One of these descriptions was proposed in a recent paper by A. Beardon and I. Short. The approach is extended to several dimensions in a way which is compatible to the early propositions of A. Beardon based on Clifford algebras.
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Rhodotorula glutinis как компонент биопленок навозных стоков
Статья научная
Анализ биопленок навозных стоков выявил ассоциацию Clostridium ssp. (91.09 %), Escherichia coli (6.07), Bacteroides sp. (1.06), Sarcina ventriculi (0.91), Klebsiella sp. (0.14 %) и дрожжи Rhodotorula glutinis в объеме 0.11 % от общего числа микроорганизмов. Пигментированные дрожжи Rhodotorula glutinis обладают низкой биохимической активностью, устойчивы к изменениям рН. В нейтральной среде (рН 7.0±0.3) количество Rhodotorula glutinis составило 0.11 % от общего числа микроорганизмов (7*104±2.2 КОЕ/мл), но при смещении рН до 5.5±0.1 (подкисление проводили 10 %-ным раствором серной кислоты) количество дрожжей выросло до 1.01 % (9*105±1,1 КОЕ/мл). Дрожжи данного вида сохраняют свою жизнеспособность при повышении температуры. Так, при нагревании до 70 оС (в биореакторных установках при сепарировании навозных стоков) количество дрожжей составило 0.06 % от общего микробного сообщества (3*102±1.2 КОЕ/мл). Выявление в свиных навозных стоках дрожжей Rhodotorula glutinis ранее в отечественной и зарубежной литературе не описано, их роль требует дальнейшего исследования.
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Spatial structure of helium trimers as confirmation of structurelessness in quatarons
Краткое сообщение
It is shown that new experimental data [1] on spatial structure of helium trimers, demonstrating absence of certain structure in them, can be considered as the proof of similar absence of structure in clusters of "hidden" phase (quatarons) in crystal-forming media. Thus it is supposed that the dynamism of structure can be as well realized in cluster structures (quatarons) with a large number of atoms (n> 3) if mainly van der Waals bonds between atoms, molecules or other structural units forming them are retained in quatarons. In the process of establishment of strong chemical bonds between atoms quatarons become more and more similar to rigid objects, which form and structure is quite predictable, while hollow quatarons, for example, carbon at covalent bonds between atoms are transformed in fullerenes.
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Stuckelberg particle in external magnetic field. Nonrelativistic approximation. Exact solutions
Статья научная
The St¨uckelberg equation for a particle with two spin states, S = 1 and S = 0, is studied in the presence of an external uniform magnetic field. In relativistic case, the particle is described by an 11-component wave function. On the solutions of the equation, the operators of energy, the third projection of the total angular momentum, and the third projection of the linear momentum along the direction of the magnetic field are diagonalized. After separation of variables, we derive a system for 11 functions depending on one variable. We perform the nonrelativistic approximation in this system. For this we apply the known method of deriving nonrelativistic equations from relativistic ones, which is based on projective operators related to the matrix Γ0 of the relativistic equation. The nonrelativistic wave function turns out to be 4-dimensional. We derive the system for 4 functions. It is solved in terms of confluent hypergeometric functions. There arise three series of energy levels with corresponding solutions. This result agrees with that obtained for the relativistic St¨uckelberg equation.
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Stuckelberg particle in external magnetic field. The method of projective operators
Статья научная
We study the St¨uckelberg equation for a relativistic particle with two spin states S = 1 and S = 0 in the presence of an external uniform magnetic field. The particle is described by an 11-component wave function consisting of a scalar, a vector, and an antisymmetric tensor. On the solutions of the equation, the operators of energy, the third projection of the total angular momentum, and the third projection of the linear momentum along the direction of the magnetic field are diagonalized. After separation of variables, a system for 11 radial functions is obtained. Its solution is based on the use of the Fedorov-Gronsky method, in which all 11 radial functions are expressed in terms of three main functions. Exact solutions with cylindrical symmetry are constructed. Three series of energy levels are found.
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Stueckelberg particle in the uniform electric field, solutions with cylindrical symmetry
Статья научная
In the present paper, the system of 11 equations for massive Stueckelberg particle is studied in presence of the external uniform electric field. We apply covariant formalism according to the general tetrad approach by Tetrode-Weyl-Fock-Ivanenko specified for cylindrical coordinates. After separating the variables, we derive the system of the first-order differential equations in partial derivatives with respect to coordinates (r, z). To resolve this system, we apply the Fedorov- Gronskiy method, thereby we consider the 11-dimensional spin operator and find on this base three projective operators, which permit us to expand the complete wave function in the sum of three parts. Besides, according to the general method, dependence of each projective constituent on the variable r should be determined by only one function. Also, in accordance with the general method we impose the first-order constraints which permit us to transform all differential equations in partial derivatives with respect to coordinates (r, z) into the system of 11 first-order ordinary differential equations in the variable z. The last system is solved in terms of confluent hypergeometric functions. In total, four independent types of solutions have been constructed, in contrast to the case of the ordinary spin 1 particle described by Daffin- Kemmer equation when only three types of solutions are possible.
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Symmetry reductions of Lindblad equations - simple examples and applications
Статья научная
Open quantum dynamics in the Markovian approximation is described by the Lindblad master equation. The Lindbladian dynamics is closed in the Liealgebra Λ = su(n), i.e. it has su(n)symmetry.We say that the Lindblad equation admits a symmetry reduction if it has an invariant vector subspaceΛ0⊂Λwith the Lie algebraic structure. Symmetryreductions restrict dynamics to smaller subspacesthat additionally are Lie algebras.In these notes, trivial reductions relying onthe reducibility of the Hamiltonian and Lindblad operators are described. Examples of nontrivial reductions in the infinite temperature limit and the paritypreserving Majorana reductions are presented. Applications to open spin dynamics are discussed.
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Tensor extensions of Lax equations
Статья научная
The Lax equations dL/dt = [M,L] play an important role in the integrability theory of nonlinear evolution equations and quantum dynamics. In this work, tensor extensions of the Lax equations are suggested with M : V → V and L : Tk(V ) → V , k = 1, 2, . . ., on a complex vector space V . These extensions belong to the generalised class of Lax equations (introduced earlier by Bordemann) dL/dt = ρk(M)L where ρk is a representation of a Lie algebra. The case k = 1, ρ1 = ad corresponds to the usual Lax equations. The extended Lax pairs are studied from the point of view of isomorphic deformations of multilinear structures, conservation laws, exterior algebras and cochain symmetries.
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U-Pb возраст плагиогранитов Малыко (Полярный Урал)
Статья научная
Приводятся первые данные о возрасте плагиогранитов, распространенных в зоне развития метаморфизованных габброноритов малыкского комплекса. Он расположен в восточной части Хадатинского офиолитового массива на По- лярном Урале. Конкордантный U-Pb возраст по пяти кристаллам циркона составляет 451?b14 млн. лет и фиксирует начало гранитообразования в Щучь- инской зоне. Эквивалентность U-Pb возраста плагиогранитов K-Ar возрасту амфиболитов (458?b24 млн. лет) подтверждает геологические данные об их од- новременном образовании при амфиболитовом метаморфизме габброноритов.
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