The PCA-seq method applied to analyze of the dynamics of COVID-19 epidemic indicators

In time series analysis using the SSA method, a univariate series is converted into the multivariate one by shifts. The resulting trajectory matrix is subjected to principal component analysis (PCA). However, the principal components can also be computed using the PCA-Seq method if segments of the original series are selected as objects. The matrix of Euclidean distances between the objects can be obtained using any method, which offers additional opportunities for time series analysis compared to the conventional SSA. In this study, the PCA-Seq method was used to analyze the dynamics of COVID-19 epidemic indicators

Combining and congruence evaluation of phylogenetic signals from different genes based on geometric approach

A new Euclidean distance based algorithm is used for analysis of congruence and combining molecular genetic data. This approach is called geometric, since Euclidean distance satisfies all metric axioms and the points representing the sequences can be placed in a geometric space without distorting the mutual distances and can be endowed with the coordinates in this space. Geometricness of Euclidean distances allows to apply to molecular data methods of multivariate analysis, which are relevant for intra- and interspecies variability investigating, visualization of possible directions of evolution, combining data and evaluation of the congruence of phylogenetic signals. The algorithm is used for the analysis of more than 1500 nucleotide sequences of two nuclear (apoB, brca1) and two mitochondrial (co1, cytb) genes of 15 Palaearctic and Nearctic shrews species of genus Sorex (Soricidae, Eulipotyphla). All sequences of each gene are represented as a set of points in Euclidean space. Centroids of a set of points belonging to the same species are calculated. The matrix of Euclidean distances between the species centroids is calculated for each gene. Mantel test is applied to estimate pairwise similarity (congruence) of interspecies distances matrices relating to different genes. nDNA genes congruence is equal 0.961, mtDNA – 0.748. All matrices of the interspecies distances are combined into a joint matrix by weighing. Joint genetic space for all species is built by principal coordinate method from the joint matrix. Several variability directions reflecting evolutionary events of different scale are visualized in a joint genetic space. In addition, the joint matrix of interspecies distances is used for building a phylogenetic tree which is consistent with the zoological systematics accepted for today. This confirms the efficiency of our proposed method

Shell forming mode effect on casting quality

The paper deals with the influence of shell forming modes on some parameters of castings: the surface and internal defects. The degree of roughness and stress concentration were determined on the castings obtained under production conditions. According to the result, it was found that the use of variable pressure in the formation of the shell ensures the purity of the casting and the reduction of the stress level in the casting

The study of proteotomic profile of mutton with consideration to the influence of feed combinatorics

The present article is devoted to the search for markers that attest the changes in the protein profile when fattening the lambs with enriched diets, taking into account tissue specificity. The purpose of scientific research was to expand scientific knowledge about the influence of essential trace elements of organic origin in the diet of lambs on the marker-proteins of skeletal muscle tissue, of myocardium and renal cortical substance. The objects of research were the tissues of the m.L.dorsi skeletal muscle, myocardium and cortical substance of the kidneys in lambs of the Edilbaev breed. These lambs received a diet with organic trace elements (iodine, selenium, silicon). To study the effect of microelements in the diets of lambs on change in marker-proteins, we ran the studies of the skeletal muscle, myocardium and cortical substance of the kidneys of lambs, using the method of two-dimensional electrophoresis. When searching for proteins which mark the action of organic additives in the fattening diet of lambs within the tissue of the myocardium and the cortical substance of the kidneys, a number of differences were noted; no pronounced effects were observed in the skeletal muscle. Enrichment of the diet of lambs with selenium derivatives led to a change in the protein composition in the kidneys cortical substance for some isoforms of selenium-containing proteins and related enzymes of the glutathione cycle. Reaction in this process of thermal shock proteins, utilization of aflatoxins and changes in proteins of energy metabolism within mitochondria of kidney cells was also revealed. The determination of functional activity, or immunofermental analysis of glutathione peroxidase 3 count in the blood, can be a promising biomarker for controlling the level of selenium digestion and the count of selenium in blood as a more rapid and cheap method in comparison with the proteomic technologies. And for assessing the rate of digestion and fixation of iodine, it seems promising to determine it via the activity of mitochondrial superoxide dismutase [Mn]. In the myocardium, the effect of digested feed additives mainly affected the mitochondrial apparatus, which changed its functional orientation, with the activation of several other metabolic cycles. These results are prerequisites for obtaining more fundamental data on the effect of diets enriched with essential micronutrients on the molecular mechanisms that take place within the myocardial and kidney tissue of lambs. New data have been obtained on the effect of diets enriched with essential microelements on the molecular mechanisms occurring in the myocardial tissue and cortical substance of the kidneys of goats and sheep. The research results obtained by proteomics methods will be used for modeling and targeted adjustment of diets in order to obtain raw materials with the necessary technological characteristics

Preparation of aluminum oxide coating on carbon/carbon composites using a new detonation sprayer

A new multi-chamber cumulative detonation sprayer (MCDS) was applied to fabricate an aluminum oxide coating on carbon/carbon composites. MCDS provides heating and acceleration of ceramic micropowders by means of combustible gas mixture detonation products with a frequency of 20 Hz and above. The ceramic aluminum oxide particle kinetic energy ensures the destruction of the weakened areas on the carbon-carbon composite material surface and the incorporation of these particles into the surface layer. The following powder particles decelerate on the already fixed particles and form a ceramic coating. The formed aluminum oxide coating is characterized by high hardness and low porosity (<1%). MCDS provides the formation of a high-quality ceramic layer, which can also serve as the basis for the formation of protective heat-resistant coating

AUTOMATION OF OPTIMAL IDENTIFICATION OF DYNAMIC ELEMENT TRANSFER FUNCTIONS IN COMPLEX TECHNICAL OBJECTS BASED ON ACCELERATION CURVES

Objectives. The aim of present paper is to minimise the errors in the approximation of experimentally obtained acceleration curves.Methods. Based on the features and disadvantages of the well-known Simoyu method for calculating transfer functions on the basis of acceleration curves, a modified version of the method is developed using the MathLab and MathCad software. This is based on minimising the sum of the squares of the experimental point deviations from the solution of the differential equation at the same points.Results. Methods for the implementation of parametric identification are analysed and the Simoyu method is chosen as the most effective. On the basis of the analysis of its advantages and disadvantages, a modified method is proposed that allows the structure and parameters of the transfer function to be identified according to the experimental acceleration curve, as well as the choice of optimal numerical values of those parameters obtained for minimising errors in the approximation of the experimentally obtained acceleration curves.Conclusion. The problem of optimal control over a complex technical facility was solved. On the basis of the modified Simoyu method, an algorithm for the automated selection of the optimal shape and calculation of transfer function parameters of dynamic elements of complex technical objects according to the acceleration curves in the impact channels was developed. This has allowed the calculation efficiency of the dynamic characteristics of control objects to be increased by minimising the approximation errors. The efficiency of the proposed calculation method is shown. Its simplicity makes it possible to apply to practical calculations, especially for use in the design of complex technical objects within the framework of the computer aided design system. The proposed method makes it possible to increase the accuracy of the approximation by at least 20%, which is an important advantage for its practical use

Диференціація генотипів сосни звичайної за поліморфізмом довжини інтронів генів дефензинів

The search for highly informative DNA markers to support the breeding programs aimed at increasing the productivity and biological stability of forest stands is an urgent task, especially in the context of global climate change. In this paper, we first investigate a new type of genetic markers based on the intron length polymorphism (ILP) of defensin genes to determine their informativeness and promising use for the estimation of the potential resistance of pine genotypes to biological damage. In the course of our study we applied the following methods: total DNA isolation by STAB method, PCR amplification with specific primers to pine defensin genes and Heterobasidion annosum s. s., electrophoretic separation of PCR fragments on a polyacrylamide gel under nondenaturing conditions, and also data analysis using software GenAlEx 6.053 and Statistica 10. Having conducted the research, we can present the following results. To investigate the defensin genes polymorphism in pine trees, we used ILP markers. These markers were developed based on the nucleotide sequences of the exons of PsDef1-4 genes. Analysis of PCR fragments obtained after amplification of each pair of primers with genomic DNA of pine showed that only one pair of primers, which is specific to defensin 2 (IPL-PsDef2), forms a wide range of amplified products, indicating their promising use for genetic characterization of genotypes of Scots pine. To clarify the use of IPL-PsDef2 markers for the study of genetic polymorphism we analyzed 196 trees and revealed that the average PIC was 0.287. IPL-PsDef2 markers were used to analyze the different genotypes of Scots pine on the areas affected by root rot disease. Based on the results of cluster analysis, the samples were divided into two groups, which differ in resistance to the root sponge. In addition, we identified PCR fragments that are specific to each of these groups and can serve as markers for the evaluation of the resistance of pine genotypes to Heterobasidion annosum. Thus, our conclusion is as follows: genotyping of defensin genes loci of pine breeding material is promising for the development of environmentally friendly technologies in order to enhance the sustainability of improved genetic material of pine trees to biotic stress.Наведено результати дослідження генотипів сосни звичайної (Pinus sylvestris L.) із використанням молекулярних маркерів на підстаі генетичного поліморфізму довжини інтронів генів дефензинів PsDef1-4. Виявлено високу інформативність маркерів на підстаі інтрону гена PsDef2 (IPL-PsDef2) для дослідження внутрішньовидового поліморфізму в сосни звичайної. Встановлено межі осередка інфекції кореневої губки (Heterobasidion annosum (Fr.) Bref.) в сосновому насадженні за допомогою полімеразно-ланцюгової реакції (ПЛР) із використанням видоспецифічних праймерів. Проведено ДНК-профілювання модельних дерев способом електрофоретичного розділення ампліконів IPL-PsDef2 маркерів. За результатами поліморфізму довжини інтронів генів дефензинів здійснено кластеризацію генотипів сосни звичайної із використанням алгоритму UPGMA. на підстаі дендрограми виділено два кластери генотипів зі 100 % бутстреп підтримкою, які відрізняються за стійкістю до кореневої губки. Методом К-середніх визначено значущість кожного з ампліконів для диференціації генотипів сосни на групи. Виявлено амплікони, які можуть бути генетичними маркерами для оцінки потенційної стійкості генотипів сосни звичайної до кореневої губки. Отримані дані щодо поліморфізму локусів генів дефензинів, а також результати кластерного аналізу вказують на перспективність використання IPL-PsDef2 маркерів для генотипування сосни звичайної

Fracture toughness of Al2O3/ZrSiO4 coatings obtained by multi-chamber gas-dynamic accelerator

In the current work the research of fracture toughness of Al2O3/xZrSiO4 composite coatings have been realized using automatic system for microhardness analysis. Al2O3/xZrSiO4 (x = 0, 3, 25 wt. %) coatings were produced from a mixture of cheap raw materials (alumina and zircon ZrSiO4) on the surface of stainless steels by a new multi-chamber gas-dynamic accelerator. It has been experimentally established that adding of ZrSiO4 increases fracture toughness of alumina coating