Computer simulation radiation damages in condensed matters

As part of the cascade-probability method were calculated the energy spectra of primary knocked-out atoms and the concentration of radiation-induced defects in a number of metals irradiated by electrons. As follows from the formulas, the number of Frenkel pairs at a given depth depends on three variables having certain physical meaning: firstly, C[d] (E[a] h) is proportional to the average energy of the considered depth of the PKA (if it is higher, than the greater number of atoms it will displace); secondly is inversely proportional to the path length [lambda]2 for the formation of the PKA (if [lambda][1] is higher than is the smaller the probability of interaction) and thirdly is inversely proportional to E[d]. In this case calculations are in satisfactory agreement with the experimental data (for example, copper and aluminum)

Quantitative and qualitative analysis of sunflower pollen (<i>Helianthus</i> L.) and it’s use in breeding work

Background. In breeding work, it is necessary to take into account such an important feature as male sterility of the hybrids obtained. If a plant has visually visible anthers and pollen, the quality of the pollen grains themselves may be low. It is necessary to carry out not only a visual analysis, but also a cytological study of pollen in order to properly assess the reproductive potential of plants.Materials and methods. Wild species, some cultivars, lines and hybrids of sunflower from the collection of the N. I. Vavilov All-Russian Institute of Plant Genetic Resources were taken as objects of research. The plants were grown on the fields of Kuban Experiment Station. Pollen was collected from preinsulated inflorescences, fixed in FAA solution and stained with acetocarmine. The ratio of fertile pollen grains to the total number of pollen grains (in %) was calculated, the diameter of the pollen grains was measured, and variability curves were drawn.Results. Mature pollen grains in sunflower are rounded, tricolpate-poral, threecelled; the average pollen diameter in cultivated sunflower is 28–32 μm; in wild species, the range is from 20– 22 μm to 32–34 μm. All accessions were divided into three groups. Fertile: high level of fertility (75–99%) and low morphological heterogeneity of pollen; the variation curve for the average diameter was characterized by one distinct peak. Most of the studied accessions were included here: cultivars, most of the lines and some of the wild species. Semi-fertile: the number of well-stained pollen grains is below 75%; there are differences in the degree of staining and size of the pollen; the variation curve had additional peaks. This group included some of the lines, hybrids and wild species. The greatest morphological heterogeneity was observed in the group of perennial interspecific hybrids. Sterile: pollen grains were absent or were observed very sporadically.Conclusion. To assess the fertility of plants, it is important not only to determine the degree of staining in pollen grains, but also to rank them by diameter and construct variation curves to reveal morphological heterogeneity of pollen

Interdisciplinary Studies of Jet Systems using Euler Methodology and Computational Fluid Dynamics Technologies

This study aims to conduct interdisciplinary research using computerized solutions to inventive problems in fluidics. The chosen direction of work relates to the scientific search for new opportunities for extremal control of the thrust vector within a complete geometric sphere (with the range of rotation angle change for the thrust vector being ±180° in any direction). This study assesses the prospects for the emergence of patentable innovative solutions for maneuverable unmanned vehicles. One of the most urgent tasks is to increase the process efficiency in forming fluid medium flow, expanding opportunities for controlling this flow parameter. The research uses an interdisciplinary approach with simulation modeling. The authors of the paper reveal new possibilities for using an ejector with two curved mixing chambers to create special jet units. Calculations (CFD) have confirmed the performance of the simulator ejector when controlling the thrust vector with 90° and 180° rotation. Manufacturing physical micromodels used additive technologies to allow simulation modeling under laboratory conditions. Using “data mining” methods, it was shown for the first time that, based on Euler’s ideas and methodology, it is possible to create a new methodology for teaching and solving inventive problems. The research results apply to power engineering and unmanned vehicles. Some results of scientific studies can be used to create special computer programs working together with artificial intelligence to create advanced techniques and technologies. Doi: 10.28991/HIJ-2023-04-04-01 Full Text: PD

Thrust Vector Control within a Geometric Sphere, and the Use of Euler's Tips to Create Jet Technology

This study aims to study the issues of choosing promising directions for the development of jet technology with the creation of energy-conserving technologies. The purpose of this article is to study the issues of choosing promising directions for the development of jet technology with the creation of energy-saving. Methodological approaches have been developed for solving inventive problems within the framework of training modern designers-inventors. A new patentable jet unit has been developed and presented, which makes it possible to control the thrust vector within a complete geometric sphere (when the thrust vector is capable of deviating to any angle ranging from +180° to -180°). For the first time, demonstration versions of a nozzle apparatus capable of realizing such flow reversals through annular channels are shown. The results of computer modeling of nozzle devices are focused on energy, production, and processing of hydrocarbons when distributing energy flows at process facilities. The individual results of the ongoing work can also be used in other industries, for instance, in the creation of small-sized high-speed unmanned vehicles for search and rescue operations. Proposals have been prepared to improve the methodology for solving inventive problems as part of the development of Leonard Euler’s ideas. Doi: 10.28991/CEJ-2023-09-10-011 Full Text: PD

Disentangling the determinants of symbiotic species richness in native and invasive gammarids (Crustacea, Amphipoda) of the Baltic region

Dispersal of alien species is a global problem threatening native biodiversity. Co-introduction of nonnative parasites and pathogens adds to the severity of this threat, but this indirect impact has received less attention. To shed light on the key factors determining the richness of microorganisms in native and invasive host species, we compared symbiotic (parasitic and epibiotic) communities of gammarids across different habitats and localities along the Baltic coast of Poland. Seven gammarid species, two native and five invasive, were sampled from 16 freshwater and brackish localities. Sixty symbiotic species of microorganisms of nine phyla were identified. This taxonomically diverse species assemblage of symbionts allowed us to assess the effect of host translocation and regional ecological determinants driving assembly richness in the gammarid hosts. Our results revealed that (i) the current assemblages of symbionts of gammarid hosts in the Baltic region are formed by native and co-introduced species; (ii) species richness of the symbiotic community was higher in the native Gammarus pulex than in the invasive hosts, probably reflecting a process of species loss by invasive gammarids in the new area and the distinct habitat conditions occupied by G. pulex and invasive hosts; (iii) both host species and locality were key drivers shaping assembly composition of symbionts, whereas habitat condition (freshwater versus brackish) was a stronger determinant of communities than geographic distance; (iv) the dispersion patterns of the individual species richness of symbiotic communities were best described by Poisson distributions; in the case of an invasive host, the dispersion of the rich species diversity may switch to a right-skewed negative binomial distribution, suggesting a host-mediated regulation process. We believe this is the first analysis of the symbiotic species richness in native and invasive gammarid hosts in European waters based on original field data and a broad range of taxonomic groups including Microsporidia, Choanozoa, Ciliophora, Apicomplexa, Platyhelminthes, Nematoda, Nematomorha, Acanthocephala and Rotifera, to document the patterns of species composition and distributio

Comparative embryological study of some Jerusalem artichoke (<i>Helianthus tuberosus</i> L.) accessions with different seed-setting ability from the VIR collection

Background. Jerusalem artichoke (Helianthus tuberosus L.) is a valuable agricultural plant, characterized by mostly vegetative propagation and depression of sexual process. This feature notably impedes breeding improvement of both Jerusalem artichoke and its hybrids with sunflower. That is why a detailed investigation of possible reasons for the failure of seed setting is very important for this crop.   Materials and methods. Jerusalem artichoke accessions from the VIR collection: cvs. ‘Topianka’ (k-70), ‘М-24-29’ (k-90), ‘2М-22-29’ (k-119), Skatovsky (k-123), and ‘Kievsky krasny’ (k-170), grown at Maikop Experiment Station of VIR, were examined. The material for embryological analysis was fixed at the stage of anthesis, processed, and analyzed at the Embryology and Reproductive Biology Lab of the Komarov Botanical Institute.   Results. A cytomorphological analysis of pollen grains and examination of anther walls and ovules with embryo sacs showed that from 51 to 95 % of the pollen grains and from 23.1 % to 66.6 % of the embryo sacs were formed normally. Abnormalities in female reproductive structures appeared more frequently but they did not determine the poor seed setting. Among the studied accessions, both cvs. ‘Kievsky krasny’, with the greatest number of abnormalities in male and female reproductive structures, and ‘Topianka’, with the smallest number, produced almost no seeds. The greatest number of seeds (from 207 to 1164) were set in ‘2M-22-29’, with the medium amount of normal generative structures, both male (pollen fertility was 81 %) and female ones (59,4 % of viable embryo sacs). Self-incompatibility observed in cv. ‘Topianka’ could cause the pollination failure, destruction of normal embryo sacs, and seed production decrease.   Conclusion. Thus, a combination of several factors (absence of developmental abnormalities in generative structures, crosspollination, and a compatible pollinizer) is necessary for successful seed setting in Jerusalem artichoke

Catastrophic models of materials destruction

The effect of concentration and type of fillers on mechanical properties of composite material based on polyimide were studied. Polyethylene terephthalate (PET, polyester), polycarbonate (PCAR) and montmorillonite (MM) were used as the fillers. The samples were prepared by mechanically blending the polyimide-based lacquer solutions with different concentrations of the second component. The concentration of filler and its class, especially their internal structure and technology of synthesis determine features of physical and mechanical properties of obtained materials. Models of catastrophic failure of material satisfactorily describe the main features depending on tension ct from deformation e

Biocompatibility of Bare Nanoparticles Based on Silicon and Gold for Nervous Cells

This work aimed to investigate the biocompatibility of bare (ligand-free) lasersynthesized nanoparticles (NPs) based on silicon (Si) and gold (Au) with primary hippocampal cultures. 1%, 5% and 7% of culture medium were replaced by 0.1 mg/mL NP solution on day 14 of culture development in vitro. Our studies revealed that the NPs caused a dose-dependent cytotoxic effect, which was manifested by an increase the number of dead cells and a decrease of the spontaneous functional calcium activity of neural networks. Au NPs revealed less pronounced cytotoxic effect than Si ones and it can be explained by larger size and better solubility of Si NPs. Keywords: bare nanoparticles, primary hippocampal cultures, neurotoxicit