Volume 18, Nº 4 (2022)

Within the framework of strain gradient elasticity of n-th order we introduce ellipticity and strong ellipticity conditions. In this theory a density of potential energy depends on deformation gradients up to n-th order. As a result, static equations constitute a system of three nonlinear partial differential equations of order 2n with respect to vector of displacements. This model is used for description of long-range interactions, which are essential at small scales. Indeed, the strain gradient elasticity describes size-effects observed at the micro- and nano-scales. In nonlinear theory of elasticity the conditions of ordinary ellipticity and strong ellipticity could be treated as constitutive inequalities among others. In particular, ellipticity is related to an infinitesimal material instability. From the mathematical point of view, ellipticity is a natural property of equations of statics, which guarantees certain properties of corresponding boundary-value problems, such as, for example, smoothness of solutions, solvability, properties of spectrum. In comparison to nonlinear theory of elasticity the conditions of strong ellipticity in gradient media are less examined. Here ellipticity conditions imply constraints on the dependence of constitutive equations on the deformation gradient of n-th order. Precisely, ellipticity implies constraints on the tangent stiffness moduli of highest order and does not imply any on the dependence of deformation gradients of smaller order. Strain gradient elasticity of n-th order could be treated as a certain gradient regularization of the model of order n-1 for any number n. From this point of view one can avoid the violation of ellipticity considering deformation gradients of higher order.

The brief review of the astronomical infrastructure of the South of Russia where the major astronomical facilities are concentrated is presented. The astronomical centers are listed with brief description for each. The prospects of development of astronomy in our country are discussed. The importance of international cooperation for the development of astronomy is noted. An exceptionally positive role in the development of domestic astronomy could be played by our country’s joining the largest international astronomical organization, the European Southern Observatory, which has the most advanced instrument park. This would allow us to overcome the technological gap that has developed over decades and gain access to all the largest telescopes in the world, however, in the current geopolitical situation, the ways for this are closed. The development of millimeter and submillimeter astronomy looks the most realistic and promising in the current situation due to the importance of this spectral range for astronomical research, the almost complete absence of appropriate instruments in Russia, prospects from the point of view of the development of relevant industrial technologies as well as the existing groundwork (projects Suffa and Millimetron). As the first step it is proposed to develop a special program for the southern region describing a number of strategically important steps and including creation of a new observatory in the North Caucasus. This should involve the participation of scientific organizations and universities in the South of Russia, including the Southern Scientific Centre of the Russian Academy of Sciences.

The article discusses the principles of material selection, technology of application and modification of metal friction surfaces using vacuum ion-plasma treatment of diamond-like coatings by physical methods. Based on quantum chemical calculations and using modern tools X-ray photoelectron and auger electron spectroscopy (XPS and OES), the energy of interatomic interactions at the boundaries of iron grains separated by atoms of various chemical elements was estimated. Using the methods of quantum chemistry, it is shown that when modeling the strength properties of nanocoatings deposited on the metal surface and consisting of atoms of elements Ti, Al, N, the influence of deep-lying layers of iron on the strength of the coating can be neglected. This effect is due to the strong shielding effect of the electronic subsystem of iron from external influences. The use of quantum chemistry methods in the work made it possible to study the effects that occur at the nanoscale and inaccessible for research using instrumentation. In particular, it was found that when carbon nanocoating is applied to the iron surface first, and then nanolayers of other elements, stratification can occur in the layer system, leading to a weakening of the overall strength of the coating. This stratification is caused by the redistribution of electron density between layers of different elements. The resulting weakening of strength may not manifest itself when measuring strength by standard methods. In this regard, when developing new types of nanocoatings on metals, along with standard methods, it is necessary to use theoretical (primarily quantum chemical) methods for assessing the strength of nanocoats. The approach considered in this paper can also be used in the development of criteria for the selection of chemical elements for modifying friction surfaces that contribute to increasing the wear resistance of heavily loaded tribosystems.

Recent days information technologies are increasingly used in various fields of human activity. There is an explosive development of a number of modern information technologies, such as neural networks, artificial intelligence, fog and cloud computing, etc. Technologies in the field of robotics, wireless communication technologies, information and control systems and computer complexes are being improved due to the emergence of a new element base. Using all these new technologies in the construction of modern information and control systems is not only important and relevant, but also necessary. It is also corresponding to modern technological challenges. The research on this area is carried out by the staff of the Laboratory of Information Technologies and Control Processes at the SSC RAS. The article reviews the scientific research and developments of the laboratory and describes the following areas of research: “Reconfigurable computing systems with high real performance”, “Collective control of groups of robots”, “Multiprocessor and neural network information and control systems for various fields of application”. The direction “Reconfigurable computing systems with high real performance” includes scientific and practical research and industrial production of high-tech basic computing modules and software development for reconfigurable computing systems with high real performance. The direction “Collective control of groups of robots” includes scientific research and practical developments in the field of creating control methods and tools for building distributed information and control systems to improve the efficiency of complex mechatronic objects, including intelligent robots. Direction “Multiprocessor and neural network information and control systems for various fields of application” includes scientific and practical research in the development of methods and tools for building distributed information and control systems, mathematical and software for such systems in order to improve security and ensure efficiency of operation of complex mechatronic facilities, monitoring and forecasting systems for various purposes. It is advisable to combine research of “Collective control of groups of robots” and “Multiprocessor information and control systems for various fields of application” in order to develop new methods for organizing and managing information and control systems that include mobile components.

The results of field experiments conducted in 2012–2022 to improve the quality of habitat and conservation of Anseriformes birds in the Western Manych are summarized in the publication. The studies were carried out in the area of the Veselovsky Reservoir, wetland of international importance. This reservoir is one of the most significant water bodies on the migration route of anseriformes. Factors influencing the state of habitats: climate and anthropogenic factors are considered. In 2000−2021 climatic conditions have become favorable for anseriformes in general, but extreme weather events affect their populations. The impact of such negative anthropogenic factors as disturbance, habitat transformation, and changes in agricultural technologies is growing. This leads to a decrease in the ecological capacity of the territory for anseriformes. The results of the mallard Anas platyrhynchos Linnaeus, 1758 reintroduction experiment, which made it possible to reduce the hunting pressure on the wild population of this species and stabilize its numbers, are discussed. Two plots with similar ecological conditions and different levels of anthropogenic impact were selected for experimental assessment of the influence of the disturbance factor on birds. It was found that in the area with a lower level of disturbance, large concentrations of some species of anseriformes, in particular mute swan Cygnus olor (Gmelin, 1789), shelduck Tadorna tadorna (Linnaeus, 1758), mallard and common teal Spatula querquedula (Linnaeus, 1758) are formed. The red-headed pochard Aythya ferina (Linnaeus, 1758) was more often recorded on the lake with a low level of disturbance, although its larger flocks stayed in the area with increased load. Mallards have been shown to make fewer breeding attempts in areas with high levels of disturbance, and they are less successful. From this it follows that the creation of protected zones in areas of concentration of breeding birds or those stopping during migration is a necessary element of the protection of Anseriformes. In an experiment on fixing the mallard for breeding in pessimal habitats, it was shown that the artificial improvement of the protective conditions of the nesting habitats and the feeding capacity of the biotope makes it possible to attract birds for nesting. Feeding conditions in the presence of safe open water spaces for roosting during the preparation of anseriformes for migration and at migration stops are a critical factor. The results of a large-scale field experiment with the organization of feeding fields for anseriformes, which made it possible to significantly increase the ecological capacity of the territory north of the Veselovsky Reservoir, are described. The concentration of mallard, ruddy shelduck Tadorna ferruginea (Pallas, 1764), greylag Anser anser (Linnaeus, 1758) and white-fronted geese A. albifrons (Scopoli, 1769) in the fodder fields has increased. The red-breasted goose Branta ruficollis (Pallas, 1769) appeared. The maximum concentration of these species in autumn 2021 was 130.000 individuals. The results of the territorial distribution of geese tagged with GPSGSM transmitters (ECOTONE) are presented to prove the effectiveness of habitat improvement.

This article is devoted to the formation of a scientific approach to managing the state of the body during the development of the tumor process. This approach is based on the discovery of the pattern of development of different general non-specific adaptational reactions depending on the acting factor intensity, which determined the prospects for increasing antitumor resistance of the organism. Changes in the state of the central nervous system, endocrine and immune systems, which distinguish antistressor adaptational reactions from each other and from the G. Selye’ stress were revealed. Signal hematological criteria of four main archetypes of reactions – training, calm and elevated activation, as well as stress – have been established. When testing factors of different nature in a wide range of intensity, a new previously unknown system of periodic repetition of the tetrad of reactions at different levels of the body’s reactivity was revealed. These ideas significantly expanded the possibilities of managing the adaptive state of the body in oncopathology, as well as in other serious diseases and aging. A new therapeutic direction was founded – the activation therapy – which uses effective regimes of treating influence on the body of factors of various nature. The possibilities of activation electromagnetic therapy as an accompanying treatment in adjuvant chemotherapy and radiation therapy of tumors of various localization were shown. The influence of neurogenic pain on the malignant process and electrophysiological processes in neurons has been studied. A new paradigm of psychosomatic medicine based on the relation of the physical and psychological state with the archetype of the integral adaptive response of the organism with multilevel mechanisms of formation (from subcellular to systemic) was presented.