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Abiotic stresses, among which extreme temperatures, salinity, drought, UV radiation, heavy metal pollution, etc., adversely affect the growth and yield of cereals, the most important group of monocotyledonous plants that have met the nutritional and other needs of mankind for thousands of years. To cope with stress, plants deploy certain adaptive strategies that combine morphological, physiological, and biochemical responses, and on which growth and productivity depend. An important place in the formation of such strategies is occupied by phytohormones - signaling biomolecules of a different chemical structure and physicochemical properties, which act in nanomolar concentrations and regulate most physiological and metabolic processes of plants. In this review, the latest literature data concerning the growth and development regulation by exogenous phytohormones in cereals under abiotic stresses have been analyzed and summarized. The effects of priming and foliar treatment with abscisic acid, gibberellins, auxins, cytokinins, brassinosteroids, jasmonic and salicylic acids on the cultivated cereals tolerance to different abiotic stressors are discussed. Peculiarities of bilateral and multilateral hormonal signaling in the formation of responses of cultivated cereals to abiotic stressors after application of exogenous phytohormones are considered. The issue of exogenous phytohormones effects on molecular mechanisms controlling the synthesis of endogenous hormones, their signaling and activity are singled out. It is emphasized that phytohormonal engineering opens new opportunities to increase yields and is seen as an important promising approach to overcoming the cereal losses caused by adverse external factors.

The understanding of space and time will always play an extremely important role for functioning of society, which is largely determined by the set of concepts supported by the dominant paradigm in science. Defining the concepts of "space" and "time" is one of the basic tasks of science and philosophy. The subsequent construction of many social life foundations and further both long-term and short-term planning of their development depends on the solution of this problem. The article considers the evolution of these concepts in historical retrospect, analyzes their metamorphosis at the current stage of digitalization of the world economy. The economy, which has undergone significant changes in the last few decades, is transforming the ontological status of the studied concepts, rapidly transferring space and time from physical reality to virtual reality, while creating new social institutions and revising relations in the existing social formations.

Purpose. Justification of the influence of pulsating dynamic loads in the surface layers of parts obtained by plastic deformation methods on the quality of finished products during cold rolling, knurling, running in, drawing and stamping. Research methodology. A schematization was adopted in which the workpiece or part is an anisotropic medium elastically bonded along the surface of the junction of external reinforced layers with the internal mass of the part. On the basis of the proposed physical model, conditions were found under which under the action of cyclic surface loads, violations of the integrity of the appearance of fracturing and waviness of external fibers in the process of strengthening the treatment of semi-finished products and parts are possible. Findings. The obtained data allows us to establish the frequency characteristics of the process of unstable parametric oscillations caused by nonlinear friction between the forming element and the workpiece (part), which lead to a deterioration in the quality of finished products. In addition, for the steady-state operating modes of machines for cold metal forming, the dependence of the amplitudes of deformation waves, as functions of the maximum pulsations of the “periodic” components of surface forces, was obtained, and measures were proposed to reduce vibroactivity in the area of tool interaction with the workpiece and machine parts for cold processing. Originality. It consists in formulating and solving the second dynamic problem for the surface layers of the workpiece at the interface of the processed layers and the workpiece array. Depending on the occurring periodic forces for the surface layers, the conditions of steady and unstable operation of the shaping tool and the whole machine for metal forming by pressure, as a whole, are determined. Practical value of the work lies in the fact that safe modes of operation of metal forming machines have been identified, conditions for improving the design of machines for cold metal forming have been created, under which the possibility of occurrence of parametric oscillations, as well as the reduction of vibratory activity of machines for cold metal forming in minimized whole. Keywords: running in, knurling, drawing, plastic deformation, roller, tool, workpiece, the amplitude of oscillations, load, excitation coefficient, steady amplitude, deformation wave.

The use of semiconductor converters is relevant in various fields of industry and electrical engineering. Real objects and their parameters are included in the article and there is a description of rectifier circuits using mathematical formulas. The results of the research object models are presented in the work by using MatLab Simulink.

The use of DC switching power supplies is relevant in various industries. DC switching power supply is considered as an example. The article contains a description of a DC power source with a power factor corrector. The results of the study of the object model considered in the article using MatLab Simulink are presented. The paper examines the characteristics of a pulse power supply for a personal computer. We also consider the possibility of using a power factor corrector to reduce the harmful effect of IIP on the supply network.

Plants of heterosporous annual fern hydrophyte Salvinia natans L. were collected in ponds of the Desniansky district of Kyiv city during summer time beginning from June, 2015 at one-month interval. Biometric studies of the whole plant (clone) and some segments of floating and submerged fronds showed that changes in the sporophyte weight and length at the various phenological phases of development occurred mostly owing to newly formed organs (modules) while linear dimensions of some formed fronds remained practically unchanged. The weight and length of an individual submerged frond considerably exceeded those of floating one. At the steady-state growth phase (July) the weight of an individual submerged frond increased two times due to an intensive formation of multi-cellular filamentous hairs while the length remained almost unchanged. During the reproductive development (August-September) the sporophyte weight increased as a result of sporocarps formation. The pattern of IAA accumulation and localization in organs of the sporophyte S. natans was for the first time analyzed using HPLC. At the phase of a fern intensive growth (June), the total IAA content of floating and submerged fronds was shown to be similarly high and reached 182 ng/g of fresh weight. During an active overgrowth and pubescence of submerged fronds (July) the endogenous IAA content was 546.3 ng/g of fresh weight while the quantity of this hormone in floating fronds remained at the level of the previous phase. A considerable reduction of this hormone content in ageing floating and submerged fronds was observed following the sporogenesis beginning at the phase of sporocarp formation and spore ripening. At the stage of late sporogenesis in the beginning of vegetative organs dying phase (September), the total IAA content in sporocarps that contained mature spores was 193 ng/g of fresh weight. The free hormone form dominated at the stage of an active and steady-state growth of floating and submerged fronds. Conjugated IAA was localized mostly in submerged fronds in quantity which exceeded that of floating ones 4 and 36 times, respectively. Distribution of this hormone between floating and submerged fronds shows that during the steady-state growth phase IAA is localized in submerged fronds, while at the phase of vegetative organs dying – in sporocarps. Specific changes in accumulation and localization of endogenous IAA revealed the correlation between growth processes and distribution, and content of phytohormone free and conjugated forms in sporophyte vegetative and reproductive organs of S. natans water fern during its individual development.

Efficacy of active draining, promoting the most rapid reconvalescence and rehabilitation of the patients, in comparison to passive wound draining was studied up in various diseases of thyroid gland and operative intervention volume. The autors have had concluded, that suturing of operative wound without draining after hemithyroidectomy conduction is possible, as well as a thyroidectomy for nodular and multinodular goiter, if the excised volume of the lobe/gland do not exceed 15 cm3 and in nonapplication of anticoagulants.

A species specific PCR test, based on manganese-dependent superoxide dismutase A encoding gene sodA, was developed for the identification of Staphylococcus hyicus, an important bacterial pathogen in pigs. The designed primers allowed a rapid and reliable identification of phenotypically characterized S. hyicus, isolated in Russia, Germany and Denmark. No cross reactivities could be observed investigating staphylococcal reference strains representing 18 different species and subspecies. The use of the described primers might improve a future diagnosis of this bacterial pathogen.

In the present study, Staphylococcus (S.) hyicus strains isolated in Russia (n = 23) and Germany (n = 17) were investigated for the prevalence of the previously described genes sheta and shetb. Sheta was detected in 16 S. hyicus strains. Sheta-positive strains were mainly found among strains isolated from exudative epidermitis, and frequently together with the exfoliative toxin-encoding genes exhD and exhC. Partial sequencing of sheta in a single S. hyicus strain revealed an almost complete match with the sheta sequence obtained from GenBank. None of the S. hyicus strains displayed a positive reaction with the shetb-specific oligonucleotide primer used in the present study. According to the present results, the exotoxin encoding gene sheta seems to be distributed among S. hyicus strains in Russia and Germany. The toxigenic potential of this exotoxin, which does not have the classical structure of a staphylococcal exfoliative toxin, remains to be elucidated.

The influence of ultrasonic loading on current-voltage characteristics has been investigated in Mo/n–n+–Si structures in the temperature range from 130 to 330 K. The longitudinal ultrasonic waves were of 8.4 MHz in frequency and had the intensity approaching 0.3 W/cm2. The acoustically induced reversible modification of the ideality factor and the Schottky barrier height was observed. The temperature dependence of the ultrasound effect was found to be non-monotonic and the parameters variation decreased with the temperature increase from 200 to 330 K. The obtained results have been analyzed on account of the inhomogeneous Schottky barrier model. The ultrasonic loading has been shown to increase the effective density of patches, the barrier height of the uniform region and the patches region and to broaden the patch parameter distribution.

Summary In the present study, previously characterized Staphylococcus hyicus isolated in Russia (n = 23) and Germany (n = 17) were investigated for the prevalence of the exfoliative toxin encoding genes exhA, exhB, exhC and exhD by multiplex PCR resulting in the detection of exhD positive strains among the S. hyicus isolated from pigs with exudative epidermitis in Russia and the detection of exhC and exhD for one and two strains isolated from exudative epidermitis in Germany respectively. The toxin gene negative strains were generally isolated from apparently healthy pigs, from other animals and from specimens where the relation between the isolation of S. hyicus and the clinical symptoms remained unclear. Partial sequencing of the toxin genes of selected exhC and exhD positive strains and comparing the sequencing results with sequences of exhC and exhD reference strains revealed an almost complete identity. The results of the present study were in agreement with the findings of Andresen and Ahrens (J. Appl. Microbiol., 96, 2004, 1265) and Andresen (J. Vet. Rec., 157, 2005, 376) that the presented multiplex PCR could be used to investigate S. hyicus for toxinogenic potential and that there is an association between the presence of toxin genes in S. hyicus strains from exudative epidermitis. However, comparable with the S. hyicus strains isolated in Germany which were investigated previously by Andresen (J. Vet. Rec., 157, 2005, 376), exhD seems to predominate in S. hyicus strains from Russia.

The computer ecological intellectual system (CEIS) is developed in the investigated regions on the basis of the object-orientated approach with the purpose to be used in systems of processing ecological information. (Voytenko, Zagorodni, 1997). The system has developed dialogue means, which allow setting base data maps for their processing through internal and external models of natural and agricultural processes. The result of such processing is new maps of the economic, ecological or social characteristics. The maps are created on the basis of researched region division into geographical elements for the supervision of necessary characteristics changes of dynamics. Thus, there is an opportunity to realise the analysis and forecasting. CEIS is logically and structurally subdivided into the subsystems. The subsystem is an abstraction. Its subclasses are versions of objects that represent the global characteristics of any mental or real territorial subsystem. According to such project and hierarchy of objects, it is obvious, that objects of derivative classes from the abstract generalised class and can submit the specialisation of the subsystems. Hence, at the centre of consideration -we have a subsystem, that displays a real current state of a pattern, which answers one of the characteristics, say, of current radiating loading in view of accommodation of pollution sources, natural-climatic conditions, sociologiceconomic structure and so on. The minimal specification of the project is determined as follows: - Biological subsystem (ground, microorganisms, viruses, plants, animals, birds); - Subsystem of environment (climatic conditions, pollution); - Subsystem of social development; - Subsystem of managing and economy. One of the external models, which is represented in CEIS, is a model of a haricot bean plant development in ontogenesis, nodule nitrogen fixing during a virus infection in different ecological conditions (Zagorodni, Boyko, Beiko 1995). As it is known, virus is a very sensitive system at change of the natural factors, therefore it can be used as the indicator of the environment state. The model uses the initial information as maps of the environment subsystem of CEIS (temperature, humidity, PH of soil, radiating, pestisidal and industrial soiling) and is a basis for the construction of new maps - maps of infection, productivity and its quality, pollution of a crop and so on. Also, through such a model, it is possible to find optimum conditions for the cultivation of a healthy vegetative material. The processes, which pass in vegetative organism, are separately given in the model. For each process, it is constructed of a function of potential force and a function of real force, which is defined under conditions of action of the laws of conservation of substances and energy. Thus, CEIS can be applied in the research of ecological processes in different conditions of investigated regions. Then the region is broken into geographical elements with the given set of abstract subsystems. As an example, a model of development of the plants in different conditions of Ukraine is shown.