Possibility of Geometric Description of Quasiparticles in Solids

New phenomenological approach for the description of elementary collective excitations is proposed. The crystal is considered to be an anisotropic space-time vacuum with a prescribed metric tensor in which the information on electromagnetic crystalline fields is included. The quasiparticles in this space are supposed to be described by the equations structurally similar to the relativistic wave equations for particles in empty space. The generalized Klein-Gordon-Fock equation and the generalized Dirac equation in external electromagnetic field are considered. The applicability of the proposed approach to the case of conduction electron in a crystal is discussed.Comment: 17 pages, latex; to appear in Int. Jnl. Mod. Phy

Impurity relaxation mechanism for dynamic magnetization reversal in a single domain grain

The interaction of coherent magnetization rotation with a system of two-level impurities is studied. Two different, but not contradictory mechanisms, the `slow-relaxing ion' and the `fast-relaxing ion' are utilized to derive a system of integro-differential equations for the magnetization. In the case that the impurity relaxation rate is much greater than the magnetization precession frequency, these equations can be written in the form of the Landau-Lifshitz equation with damping. Thus the damping parameter can be directly calculated from these microscopic impurity relaxation processes

Метод реінтродукції як захід активного збереження видів роду Stipa L.

Donetsk National University – Topicality of ecological and botanical research of steppe associations is conditioned both by scientific requirements (ecological and cenotic niches, potentials; steadiness and dynamism; diagnostics and control of the state of ecosystems balance) and practice of land tenure and resource preservation. As a result of the inventory on the territory of the RLP «Kleban-Byk» 13 species of Stipa were identified. In the course of the research it was stated that the age state of the populations is not satisfactory and demands reintroduction measures. In cases when anthropogenic impact leads to disappearance of these species from the complex of vegetable groups, there is need of their reintroduction, its successfulness having been proved for S. dasyphyllа and S. capіllata. Актуальність еколого-ботанічних досліджень степових угруповань зумовлена і потребами науки (еколого-ценотичні ніші, потенціали; стійкість та динамізм; діагностика та контроль стану збалансованості екосистем), і практики землекористування та ресурсозбереження. У результаті інвентаризаційних робіт на території РЛП «Клебан-Бик» було визначено 13 видів ковил. Більшість видів роду Stipa L., які зростають на території РЛП «Клебан-Бик», мали регресивні популяції або тенденцію до регресивності й знижений рівень відновлення особин. Коли антропогенний вплив призводить до зникнення зі складу рослинних угруповань цих видів, виникає потреба їх реінтродукції, найбільшу успішність упровадження якої доведено для S. dasyphyllа і S. сapіllata.Department of Biology, Donetsk National Universit

Speckle Interferometry with CMOS Detector

In 2022 we carried out an upgrade of the speckle polarimeter (SPP) -- the facility instrument of the 2.5-m telescope of the Caucasian Observatory of the SAI MSU. During the overhaul, CMOS Hamamatsu ORCA-Quest qCMOS C15550-20UP was installed as the main detector, some drawback of the previous version of the instrument were eliminated. In this paper, we present a description of the instrument, as well as study some features of the CMOS detector and ways to take them into account in speckle interferometric processing. Quantitative comparison of CMOS and EMCCD in the context of speckle interferometry is performed using numerical simulation of the detection process. Speckle interferometric observations of 25 young variable stars are given as an example of astronomical result. It was found that BM And is a binary system with a separation of 273 mas. The variability of the system is dominated by the brightness variations of the main component. A binary system was also found in NSV 16694 (TYC 120-876-1). The separation of this system is 202 mas.Comment: 24 pages, 27 figures. Minor style differences with respect to version accepted to Astrophys. Bull. V. 78, no.

Higher education competitiveness : definition, assessment and ways of growth

The article is devoted to the search and the description of marketing reserves determining perspective competitiveness of higher educational establishments. The study refers to highly efficient institutions possessing the development potential and their own operational and marketing possibilities to comparative ways of growth. The research led to a conclusion that it is necessary to actualize the marketing competence of the Russian higher educational establishments based on the modernization of the educational activity through the development of the full-fledged training and production complexes providing the students with employment experience and real labor activity.peer-reviewe

On Uniqueness of Boundary Blow-up Solutions of a Class of Nonlinear Elliptic Equations

We study boundary blow-up solutions of semilinear elliptic equations $Lu=u_+^p$ with $p>1$, or $Lu=e^{au}$ with $a>0$, where $L$ is a second order elliptic operator with measurable coefficients. Several uniqueness theorems and an existence theorem are obtained.Comment: To appear in Comm. Partial Differential Equations; 10 page

Shot Noise in Mesoscopic Transport Through Localised States

We show that shot noise can be used for studies of hopping and resonant tunnelling between localised electron states. In hopping via several states, shot noise is seen to be suppressed compared with its classical Poisson value $S_I=2eI$ ($I$ is the average current) and the suppression depends on the distribution of the barriers between the localised states. In resonant tunnelling through a single impurity an enhancement of shot noise is observed. It has been established, both theoretically and experimentally, that a considerable increase of noise occurs due to Coulomb interaction between two resonant tunnelling channels.Comment: 7 pages, 5 figures; Proceedings of the 10th Conference on Hopping and Related Phenomena (Trieste 2003); requires Wiley style files (included

The Realization by Foreign Citizens of the Right to Unite in Labor Unions: Problems and Solutions

The article deals with the problem of limiting the possibility of membership of foreign citizens and stateless persons which temporarily staying in the territory of the Russian Federation in the Russian labor unions. Based on the study of legislation and practice of its application the authors note that the protection of the rights of workers by labor unions is called upon to supplement state mechanisms for the protection of citizens’ rights and is optional. Realization of the workers’ interests is practically impossible in the absence of their effective association therefore the restrictions that are established for foreign citizens temporarily staying in Russia and stateless persons with regard to membership in labor unions must be assessed from the point of view of ensuring their interests in the field of labor. Objective justification of the ban for the participation to the Russian labor union for a foreign citizen and a stateless person which temporarily staying in the Russia is the absence of long term communication with the Russian Federation for these persons and the short term nature of their interests in the field of labor. At the same time taking into account the possibility of long time employment to these persons in Russia the authors propose to recognize the right to the participation in the labor union for foreign citizens which are skilled workers and work on the basis of a work permit