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High-quality genome sequences help to elucidate the genetic basis of numerous biological processes and track species evolution. For flax (Linum usitatissimum L.)—a multifunctional crop, high-quality assemblies from Oxford Nanopore Technologies (ONT) data were unavailable, largely due to the difficulty of isolating pure high-molecular-weight DNA. This article proposes a scheme for gaining a contiguous L. usitatissimum assembly using Nanopore data. We developed a protocol for flax nuclei isolation with subsequent DNA extraction, which allows obtaining about 5 μg of pure high-molecular-weight DNA from 0.5 g of leaves. Such an amount of material can be collected even from a single plant and yields more than 30 Gb of ONT data in two MinION runs. We performed a comparative analysis of different genome assemblers and polishers on the gained data and obtained the final 447.1-Mb assembly of L. usitatissimum line 3896 genome using the Canu—Racon (two iterations)—Medaka combination. The genome comprised 1695 contigs and had an N50 of 6.2 Mb and a completeness of 93.8% of BUSCOs from eudicots_odb10. Our study highlights the impact of the chosen genome construction strategy on the resulting assembly parameters and its eligibility for future genomic studies.

The problems that arise in the surface layer of the soil during periodic emissions at nuclear power plants are considered. The necessity of constant monitoring of this soil layer at different times of the year is substantiated. Various methods of this control are considered. It has been established that it is extremely difficult to implement them in remote areas. A method has been developed for monitoring the surface layer of the soil using aerodynamic survey of the distribution of γ-radiation on the soil surface. This is extremely important during the preparation of agricultural fields for sowing crops in the spring. A new algorithm for restoring images obtained using aerodynamic imaging of γ-radiation is proposed. The results of a new algorithm for image processing and identification are presented.

The problems of river pollution with various hazardous elements on the example of the Volkovka river are considered. A study of water from various regions of the Volkovka river was carried out for the presence of various chemical compounds and elements in them. A relationship has been established between the location of the river bed in the city and the level of pollution by various compounds. The comparison of the measurement results with the previously obtained data is carried out and the tendency of changes in pollution is established.

The necessity of controlling emissions of carbon – 14 (14C) isotope into the atmosphere during the operation of a nuclear power plant is substantiated. It is determined that the main negative effect of the carbon isotope 14C has on humans and animals. Plants are less susceptible to this influence. A method for measuring the emission into the atmosphere of 14C is proposed. The analysis of various studies on the amount of 14C emissions at various nuclear power plants was carried out. The calculation of the amount of carbon isotope 14C is performed. The annual radiation dose of the population from the release of 14C was estimated. Various options for reducing the amount of 14C in emissions at nuclear power plants are considered.

Not perfectly conducting lattices with a large number of different widths slots on a period are considered. The structure obtained at the n-th step of constructing of generalized Cantor set with the required ratio of the lengths of the smallest strips and slots is located inside the period. A computational experiment was carried out using models based on systems of hypersingular and singular integral equations. The characteristic properties of scattered fields are described for various values of geometric parameters and wavenumber.

The comprehensive study (electron microscopy, mass-spectrometry of secondary ions, Raman spectroscopy) of zircon from harzburgite inclusion in granulites of the Bug complex (Ukrainian Shield) is carried out. Based on a number of features, the studied zircons are subdivided into three groups. Zircon from the first group is of igneous genesis and crystallized 2.8 Ga ago at the temperature of about 650°C from a melt of orthopyroxenite composition. Zircon from the second group underwent hydrothermal alteration ca. 2.75 Ga ago at the temperature of about 750°C. Zircon from the third group is distinctive in several geochemical characteristics (higher Lu/Hf ratio, etc.) and formed before the hydrothermal process, but their compositions were altered by the fluid. Conditions of the igneous zircon (first group) crystallization were characterized by the higher $${{f}_{{{{{\text{O}}}_{{\text{2}}}}}}}$$ value, compared to the later hydrothermal alteration. The hydrothermal process has provided the distortion of zircon crystal lattice, which is reflected in the Raman spectra, and the formation of amorphous structure in the uranium-rich zircon from the third group. In terms of trace element contents, the first and second zircon groups indicate different initial melts (from which they originated) from the third zircon group; the melt of the third group was more mafic. The obtained results support the idea about the hybrid character of the melt and that the rock formed in two main stages, namely, a magmatic one and fluid alteration, separated in time and having different oxidation-reduction conditions.

Flax (Linum usitatissimum L.) is used for the production of textile, oils, pharmaceuticals, and composite materials. Fusarium wilt, caused by the fungus Fusarium oxysporum f. sp. lini, is a very harmful disease that reduces flax production. Flax cultivars that are resistant to Fusarium wilt have been developed, and the genes that are involved in the host response to F. oxysporum have been identified. However, the mechanisms underlying resistance to this pathogen remain unclear. In the present study, we used transcriptome sequencing data obtained from susceptible and resistant flax genotypes grown under control conditions or F. oxysporum infection. Approximately 250 million reads, generated with an Illumina NextSeq instrument, were analyzed. After filtering to exclude the F. oxysporum transcriptome, the remaining reads were mapped to the L. usitatissimum genome and quantified. Then, the expression levels of cinnamyl alcohol dehydrogenase (CAD) family genes, which are known to be involved in the response to F. oxysporum, were evaluated in resistant and susceptible flax genotypes. Expression alterations in response to the pathogen were detected for all 13 examined CAD genes. The most significant differences in expression between control and infected plants were observed for CAD1B, CAD4A, CAD5A, and CAD5B, with strong upregulation of CAD1B, CAD5A, and CAD5B and strong downregulation of CAD4A. When plants were grown under the same conditions, the expression levels were similar in all studied flax genotypes for most CAD genes, and statistically significant differences in expression between resistant and susceptible genotypes were only observed for CAD1A. Our study indicates the strong involvement of CAD genes in flax response to F. oxysporum but brings no evidence of their role as resistance gene candidates. These findings contribute to the understanding of the mechanisms underlying the response of flax to F. oxysporum infection and the role of CAD genes in stress resistance.

The article is aimed at researching the tools and parameters of assessing the effectiveness of innovation activity, increasing the competence of tourism enterprises, improving the competitiveness of innovative enterprises, international tour-operator-ranking. The system of tourism multipliers is substantiated, which special constituents are: an innovation multiplier, which represents an increase in income in the tourism economy, possible as a result of the implementation of a new product, changes in service technology, in the marketing, process, service, organizational or other innovations; also the company’s sustainability growth multiplier as an indicator of the estimated business reputation of the tourism company as part of the overall corporate strategy, market share and participation in the distribution/redistribution of tourist flows.

Виконано аналіз існуючих досліджень процесу термічної обробки вуглецевої сировини. Визначено, що поза увагою дослідників залишається дослідження впливу таких технологічних параметрів, як сила струму, що підводиться, та швидкості завантаження/вивантаження матеріалу на температурні поля робочого простору електрокальцинатора. Проведено дослідження зміни температурного поля робочого простору електрокальцинатора в залежності від сили струму, що підводиться, та швидкості завантаження/вивантаження матеріалу

The results of long-term routine measurements of the concentration of major ions in the water of the Lake Baikal pelagic zone, the Angara River source, and main tributaries of the lake are analyzed. The average values of ion concentration in the water column of the lake and in the Angara River obtained for the recent decade are presented and compared with the data of previous studies. Long-term trends in the concentration of ions in the main Baikal tributaries are shown. Under low-water conditions, the inflow of ions to Lake Baikal through tributaries decreases despite an increase in their concentration in river water. Changes in the chemical composition of water in the tributaries did not affect the ionic composition of water in the Lake Baikal pelagic zone and in the Angara River source.

This article presents the results of comparative studies of the frequency and distribution of chiasmata in pollen mother cells (PMCs) in five diploid tomato species, Solanum lycopersicum, S. pimpinellifolium, S. peruvianum, S. habrochaites, and S. neorickii, and one autotetraploid species, S. pimpinellifolium. It was established that under the same growing conditions, the total chiasma frequency in the cell depended on the species. At the same time, the green-fruited species S. peruvianum, S. neorickii, and S. habrochaites differed in distal chiasma frequency, while the red-fruited species S. lycopersicum and S. pimpinellifolium differed in interstitial chiasma frequency. It was shown that the total chiasma frequency in PMCs of plants of one species is a stable index of recombination potential that does not depend on the growing conditions. The redistribution between distal and interstitial chiasmata was found to be more variable, depending on the species, year, geographic growth conditions. In autotetraploid, the chiasma frequency per bivalent was lower than that in diploid S. pimpinellifolium plants, primarily due to interstitial chiasmata, the frequency of which remained at the level characteristic for diploid plants. It was concluded that the recombination plasticity of the tomato genomes was due to the redistribution of chiasmata along bivalents, and not to the change in their number in the cell.

The high quality of the carbon raw materials heat treatment control reduces the defective products output in carbon products manufacturing on subsequent stages and improves finished products quality. Synthesis of such systems is possible only under processes that take place at this production stage in detailed study condition. Taking into account that it is practically impossible to carry out research on real objects, the only alternative remains the mathematical modeling method. Considering significant amount of time of the complete process of mathematical model calculating, there is a need to find and implement methods for its simplification. In this study, the choice of Fourier method to simplify carbon materials heat treatment in electric calciner mathematical model was substantiated based on the existing simplifying mathematical models with distributed parameters of methods analysis. A simplified mathematical model of this process is developed. The optimal simplified mathematical model structures are determined. Their parametric identification was carried out. Correspondence of the calculation results using the simplified and initial mathematical models was investigated. As a result, we obtained a model that accurately maps the temperature fields obtained using the full model, and has a rather insignificant calculation time (several seconds). In future studies it is planned to conduct a model adequacy examination with experimental data. After this, the model can be used as a further electric calciner working zone in carbon material heat treatment process temperature fields study, and for this process control system in real time synthesis.

Constant growth and development of society contribute to increasing consumption, which leads to the development of production, but also increases competition and product requirements. High-quality goods can only be obtained using modern digital systems. For their synthesis it is necessary to make a large number of experiments with the equipment, that can lead to significant losses. The best solution is to create models that allow getting results quickly and without significant manufacturing costs. A discrete model of extruder with varied power capacities of heaters in a cylindrical coordinate system has been obtained, taking into account the temperature distribution along the length for each element, as well as the temperature distribution along ISSN 1728-4260 ВІСНИК ЖДТУ. 2019. № 1 (83) 323 the radius of the barrel and the screw. The model allows taking into account the influence of the heat current of each individual heater to change the total thermal field. Changes in heat capacity and density in accordance with the phase composition of the polymer have been taken into account. Dynamics of the phase composition of the polymer is also provided, depending on the current thermal and material flows. An algorithm for calculating the phase composition of a polymer is developed, depending on the previous value and its temperature. The obtained model can be used to predict the quality of the finished polymer product and to synthesize the control system taking into account the effect of heterogeneous perturbations.

Mafic granulites (metamorphosed tholeite-komatiite volcanic rocks) represent the inclusions in gneissenderbite of the Bug complex (southwest of the Ukrainian shield). The studied mafic inclusion has two zircon generations of magmatic origin that yield, respectively, SHRIMP zircon U–Pb ages of 3628±58 Ma and 2845±65 Ma. The first age is the oldest date the earliest stage of basic magmatism on the Ukrainian shield. The age of the second zircon is interpreted as a result of partial melting, synchronous with the metamorphism in the area.

In interspecific hybrids a decrease in genetic exchanges between chromosomes from different species and negative interactions between functionally incompatible loci limit genetic variation among the progeny. Earlier the fraction of crossover genotypes was increased in intraspecific hybrids of the cultivated tomato Solanum lycopersicum with the expression of the recA Escherichia coli gene. In this research transgenic hybrids between S. lycopersicum and some wild tomato species were obtained in order to study the effect of recA gene expression on the frequency of crossovers in the progeny of interspecific hybrids. Interspecific hybrids showed negative interactions between the loci of the cultivated tomato and the S. cheesmaniae, S. pimpinellifolium, and S. habrochaites species. In the latter case it resulted in semilethal necrosis. The recA gene expression in interspecific hybrids with S. cheesmaniae partially compensates among the F2 progeny the deficiency of recessive genotypes at the Wv:wv locus of chromosome 2. In general, the fractions of crossover genotypes in the F2 progeny were higher in transgenic interspecific hybrids than in control non-transgenic hybrids of the same combination of crossing, but lower than in intraspecific S. lycopersicum hybrids.

The topicality of the research is determined by the detailed study of the peculiarities of the geological structure of Boryslav-Pokuttia zone of the Precarpathian deflection, in particular of local structural forms as probable traps for oil and gas, for reliable prediction of the oil and gas potential of the subsoil. Boryslav-Pokuttia zone of the Precarpathian deflection refers to one of the oldest oil and gas producing regions in Ukraine. Its hydrocarbon potential is far from being exhausted. The complex block structure of Boryslav-Pokuttia zone requires the development of specific methods for conducting oil and gas prospecting. In this regard, determining the distribution nature of the local structures and specifying the peculiarities of their morphological forms in the area under investigation are of great importance. The issue of tracing tectonic disturbances and determining their screening ability which determines the possible existence of hydrocarbon deposits remains to be an urgent matter. Solving these issues will significantly improve the geological efficiency of prospecting and exploration in the areas of Boryslav-Pokuttia zone. At the modern stage of the Earth sciences development computer processing of geological data is widely used.Therefore, along with the traditional approach to describing structures as potential traps for oil and gas, it isnecessary to analyze their quantitative (numerical) parameters. It gives a possibility to confirm the stablished regularities more reasonably. Handling large array of quantitative indicators of local structures and the dependencies established among them makes it possible to simulate the processes that formed them and to determine the regularities of their distribution. The most important scientific and practical results include: the quantitative indicators ranking of the local structures of Boryslav-Pokuttia zone (the ranking contains four groups of structures classified according to their morphological texture); the investigated conditions for the formation of morphological varieties of local structures and the character of the distribution of tectonic deformations in them. The results of geological and mathematical simulation according to a complex of quantitative indicators help to state that local structures with certain morphological features, which are revealed to various extent in their deformations, are formed by tectonic movements of different magnitude and direction and are described by the numerical parameters peculiar only to them. Investigating the distribution of tectonic stresses and deformations, which can be estimated in quantitative indicators, will contribute to a more reliable prediction of the oil and gas potential of the subsoil. In its turn, it will improve significantly the geological performance of oil and gas prospecting in the areas of BoryslavPokuttia zone of the Precarpathian deflection.

In the present study, the optical absorption of a semiconductor surface covered with metallic spheroidal nanoparticles is considered theoretically. The theoretical approach used for calculation of light absorption in such structures is based on the concept of effective susceptibility and made in the frame of Green’s functions theory. The effective susceptibility is taken in an analytical form. The absorption spectra were calculated for coverages with nanoparticles having different shapes and surface densities at different angles of external light incidence. The obtained results predict strong configurational resonances in the spectral range where the absorption is maximum, i.e. resonant enhancement of absorption by nanoparticles of certain shape and surface density. The developed technique of calculation can be further applied to calculation of various effects caused by the excitation of surface plasmons in metallic nanoparticles under applied external fields yielding a wide range of applications of such structures in many fields, such as biomedicine, solar energy, environment protection, and information storage technology. Keywords: Semiconductor surface, Metal nanoparticles, Configurational resonance, Absorption spectrum, Effective susceptibility

The Sr isotope characteristic of carbonate rocks in the Central Azov Group has been reported (0.70322–0.70352), the Nd model age of silicate sediments has been calculated (2.34–2.31 Ga), and the U–Pb age of trondhjemites (2052 ± 5 Ma) breaking through carbonates was determined. According to the data obtained, the marine sedimentary cover of the Azov block making up the Early Precambrian Sarmatia Continent was formed in the Early Paleoproterozoic 2.23–2.34 Ga ago.

The development of optimal control of the process of baking carbon products involves consideration of the influence of characteristic zones of the furnace and uniformity of the temperature field of workpieces. This statement suggests the development of a distributed-parameter mathematical model of the furnace. It is known that the calculation time of such models is quite large, and then their application in real time is impossible. According to the above, for further development of the optimal control system of the baking process, there is a need to reduce the full mathematical model providing the necessary calculation time. The reduced mathematical model of the baking process, which differs from the known models in shorter calculation time was developed and investigated in compliance with accuracy requirements. It is found that for cases of using n>15 first basis vectors, the restriction on the permissible error of approximation of the values of Fourier coefficients is fulfilled. The possibility of choosing the optimal structure of identification models determines the possibility of obtaining temperature images of the reduced mathematical model with the necessary accuracy. The results obtained allow flexible selection of the reduced mathematical model in accordance with the technical capabilities of computing equipment. Given that in the process of baking carbon products, the defining temperatures are workpiece temperatures, only control points of workpieces were selected for the quality study of reduced models. Since the process of baking carbon products consists of three main stages, three reduced mathematical models of these stages were implemented for adequate modeling of such a process. The study of the accuracy of reduced models included comparisons of temperature values calculated by the reduced model with temperatures calculated by the initial model, which in this case was considered as a generator of experimental data

The paper demonstrates how machining and chemical polishing affect the residual stresses and surface roughness of SLM-produced Ti-6Al-4V specimens. The machining methods include surface brushing with a metal brush, and sandblasting. These pre-machining methods are thus found to generate compressive residual stresses on the specimen surface, which enhances the operating properties of parts.