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The article presents the results of experimental studies of the accuracy of measuring navigation parameters by a receiver of global navigation satellite systems (GNSS receiver) equipped with an antenna array. The use of ring antenna arrays in GNSS receivers is substantiated. The main advantage of such antenna arrays is their invariance to the direction of the main lobe of the radiation pattern in the azimuthal plane. However, ring antenna arrays have some disadvantages. The use of the minimum required number of radiators in such antenna arrays to form a beam of a given width leads to a simultaneous increase in the level of side lobes. However, when using ring antenna arrays in GNSS receivers, this drawback can be neglected, since the level of side lobes significantly affects the quality of navigation signal reception only with powerful signal re- reflections. The structure of the hardware- software complex for research is given and the principle of its operation is described. Its main parts are a 24-channel beam- forming GNSS receiver and an 8-element ring antenna array. The software and hardware complex allows the study of various configurations of antenna arrays – two, four and eight elements. The technique of carrying out the experiment is given. A eature of the technique is the use of differences in measured pseudoranges using a single antenna and various configurations of antenna arrays. The results of measurements of code and phase pseudorange are presented.

Meta-analysis of transcriptomic data from different experiments has become increasingly prevalent due to a significantly increasing number of genome-wide experiments investigating gene expression changes under various conditions. Such data integration provides greater accuracy in identifying candidate genes and allows testing new hypotheses, which could not be validated in individual studies. To increase the relevance of experiment integration, it is necessary to optimize the selection of experiments. In this paper, we propose a set of quantitative indicators for a comprehensive comparative description of transcriptomic data. These indicators can be easily visualized and interpreted. They include the number of differentially expressed genes (DEGs), the proportion of experiment-specific (unique) DEGs in each data set, the pairwise similarity of experiments in DEG composition and the homogeneity of DEG profiles. For automatic calculation and visualization of these indicators, we have developed the program InterTransViewer. We have used InterTransViewer to comparatively describe 23 auxin- and 16 ethylene- or 1-aminocyclopropane-1-carboxylic acid (ACC)-induced transcriptomes in Arabidopsis thaliana L. We have demonstrated that analysis of the characteristics of individual DEG profiles and their pairwise comparisons based on DEG composition allow the user to rank experiments in the context of each other, assess the tendency towards their integration or segregation, and generate hypotheses about the influence of non-target factors on the transcriptional response. As a result, InterTransViewer identifies potentially homogeneous groups of experiments. Subsequent estimation of the profile homogeneity within these groups using resampling and setting a significance threshold helps to decide whether these data are appropriate for meta-analysis. Overall, InterTransViewer makes it possible to efficiently select experiments for meta-analysis depending on its task and methods.

Abstract First physics results of the BM@N experiment at the Nuclotron/NICA complex are presented on π + and K + meson production in interactions of an argon beam with fixed targets of C, Al, Cu, Sn and Pb at 3.2 A GeV. Transverse momentum distributions, rapidity spectra and multiplicities of π + and K + mesons are measured. The results are compared with predictions of theoretical models and with other measurements at lower energies.

RNA isolation from fungi and fungus-like organisms is not an easy task. Active endogenous RNases quickly hydrolyze RNA after the sample collection, and the thick cell wall prevents inhibitors from penetrating the cells. Therefore, the initial collection and grinding steps may be crucial for the total RNA isolation from the mycelium. When isolating RNA from Phytophthora infestans, we varied the grinding time of the Tissue Lyser and used TRIzol and beta-mercaptoethanol to inhibit the RNase. In addition, we tested the mortar and pestle grinding of mycelium in liquid nitrogen, with this method showing the most consistent results. During the sample grinding with the Tissue Lyser device, adding an RNase inhibitor proved to be a prerequisite, and the best results were achieved using TRIzol. We considered ten different combinations of grinding conditions and isolation methods. The classical combination of a mortar and pestle, followed by TRIzol, has proved to be the most efficient.

The article presents the results of experimental studies of mutual high-precision navigation methods for unmanned and specialized transport systems. The proposed methods are based on the application of the relative operating modes of two or more angle-measuring receivers of global navigation satellite systems signals. To conduct research, a software and hardware complex has been developed, consisting of two angle-measuring receivers of global navigation satellite systems signals, a turntable and a computer model of the navigation system of unmanned and specialized transport systems. It provides the positioning error of the antenna system in angular coordinates less than 1 arc minute, which allows it to be used as a reference when measuring the angular displacements of the receiver of global navigation satellite systems signals antenna system. The results of measurements of planar and angular coordinates both in autonomous and relative phase modes of operation of goniometric receivers global navigation satellite systems signals are presented and analyzed. It has been established that the root-mean-square error of measuring relative coordinates was 0,019 meter. A further increase in the relative position measurement accuracy is possible by taking measures to reduce the multipath reception error, which is the most significant uncorrelated position measurement error by two sets of receivers of global navigation satellite systems signals. Thus, the methods of mutual high-precision navigation using angle-measuring receivers of global navigation satellite systems signals have high accuracy without the use of external information about differential corrections. This will allow the operation of unmanned or special transport systems in hard-toreach and northern regions, in conditions of lack of communication and other adverse factors.

In conditions of a significant reduction in the amount of wastewater, associated with a drop in industrial production in Ukraine in recent decades, the mineralization of surface waters of Dnipro river and other rivers of its basin decreased. This generally contributes to their recovery. At the same time, mining (including iron ore enterprises) continues to be one of the largest environmental pollutants. There are Ga, Ge, Be, ,n, V, Mn, Ca, Cu, Te, Cr, Si, Pb, Mq, Ba, Zn, Zr, Au and other chemical elements in the rocks of iron ore deposits. Mining enterprises often border agricultural land, where chemical elements of varying degrees of danger fall into the soil as a result of fertilizing and treating plants with pesticides. Almost complete saturation with specific soil elements leads to the fact that a new portion of these ele-ments obtained with fertilizers can freely migrate to underground aquifers (mainly to the first non-pressure aquifer) and, as a result of sur-face flushing from the catchment area, ultimately, fall into surface watercourses and pollute them. On the example of Krivbas it is shown that due to the combined action of factors of industrial (and, first of all, mining) and agricultural activity in the region, new stable natural and technogenic geosystems have long been formed, in which surface and underground waters and aeration zone are the most vulnerable elements. In modern conditions of reducing the negative impact of industrial (including mining) production, the question of studying the environmental impact of the activity of the agro-industrial complex and determining its share in the total technogenic load of the south of Krivbas is becoming increasingly relevant. The main pollutants of soil and groundwater (and hereinafter - surface water and bottom sedi-ments) in this region, together with mining waste, include fertilizers and pesticides that are excessively introduced into the soil. The issue of pollution of farmland bordering mining facilities requires a detailed comprehensive study, including development of a method for distin-guishing between the influence (contribution) of mining and agricultural complexes in the pollution of a specific territory.

Iron-containing oxides are the most important functional substance class and find a tremendous variety of applications. An attractive modern application is their use in biomedical technologies as components in systems for imaging, drug delivery, magnetically mediated hyperthermia, etc. In this paper, we report the results of the experimental investigation of submicron Y3Fe5O12 garnet particles obtained in different sizes by solution combustion synthesis (SCS) using glycine organic fuel to discuss the interdependence of peculiarities of the crystal and magnetic structure and size’s influence on its functional magnetothermal performance. A complex study including Mössbauer and Raman spectroscopy accompanied by X-ray diffractometry, SEM, and measurements of field and temperature magnetic properties were performed. The influence of the size effects and perfectness of structure on the particle set magnetization was revealed. The ranges of different mechanisms of magnetothermal effect in the AC magnetic field were determined.

The energy profiles of various configurations of the tetra-n-butylammonium ion (Bu4N+) arising by changing the angle between a pair of butyl ligands, as well as by rotating of various alkyl fragments in gas phase, were calculated using DFT methods. A hypothesis about the most probable way of changing the conformations of tetra-n-butylammonium ions during the phase transitions in highly conductive solid electrolytes was proposed.

The hadronic part of the electron structure function F2e has been measured for the first time, using e+e− data collected by the DELPHI experiment at LEP, at centre-of-mass energies of s=91.2–209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F2e data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F2γ analyses and help in refining existing parameterisations.

The report describes the Monte-Carlo simulation software developed for the projective geometry version of the electromagnetic calorimeter of the MPD detector. The results of software tests and some characteristics of the calorimeter are presented.