The aim of the work was to conduct a comparative phylogenetic analysis based on wgSNP of complete genomes of Brucella melitensis strains circulating in the territory of the Russian Federation. ...Materials and methods . wgSNP typing of 412 B. melitensis strains of the main genetic lineages of brucella from different regions of the world, including 64 strains isolated in the regions of the European and Asian parts of the Russian Federation, was performed. DNA sequencing was conducted on the “Ion GeneStudio S5 Plus” platform (“Life Technologies”, USA) using the “Ion Plus Fragment Library Kit library preparation” (“Life Technologies”, USA), according to the “Ion 520™ & Ion 530™ Kit – Chef” protocol (Revision D.0). Results and discussion . It has been established that the strains circulating in Russia belong mainly to genotype II, which has a wide geographical distribution across the territory of Eurasia. At the same time, subgenotype IIh prevails in the regions of Siberia, and Iii – in the European territory of the country. For the first time, sets of specific SNPs have been identified that allow for intraspecific differentiation of B. melitensis strains. The obtained results made it possible to determine the probable routes of introduction of the causative agent of brucellosis into the territory of the Russian Federation from China and the countries of the Middle East. The prospect of using an optimized wgSNP typing scheme to solve urgent problems in the field of molecular epidemiology of brucellosis is demonstrated. It includes determining the genotype and subgenotype of the pathogen associated with the probable geographical region of origin of infection, and identifying the genetic relations between strains with high accuracy.
The influence of defects induced by irradiation with fast electrons on the anisotropy of the electrical resistance of
YBa
2
Cu
3
O
7
-
δ
is investigated. The radiation exposure causes a decrease in ...the anisotropy of the electrical resistance in the normal state, thereby contributing to the isotropization of the quasiparticle spectrum due to the formation of a large number of defects in the form of Y, Ba, and Cu atoms displaced from their regular positions. The anisotropy is also expressed in the existence of various conductivity mechanisms along and across the layers. Thus, the anisotropy of the ideal phonon resistance, which exists both along and across the layers, increases with increasing temperature, tending to a constant value. In the region of the superconducting transition, a broadening of the transition due to the presence of microscopic inhomogeneities is observed in the plane of the layers, and several superconducting transitions are revealed across the layers due to the presence of macroscopic inhomogeneities in the sample.
Introduction. To improve the epidemiological surveillance of brucellosis in Russia, a detailed analysis of incidence and characteristics of Brucella melitensis strains circulating in the territories ...of the country where there is a persistent epizootic and epidemiological problem with brucellosis is required.Purpose of the study. To study current trends in the brucellosis epidemic process and perform molecular analysis of Brucella isolates from the territories of Southern and North Caucasian Federal Districts with long lasting unfavorable situation with brucellosis — the Republics of Dagestan (RD), Kalmykia (RK) and Stavropol Krai (SK).Materials and methods. The analysis of the brucellosis incidence in the North Caucasus Federal District and the Southern Federal District was carried out on the basis of data from the Rospotrebnadzor Departments for the period 2011–2020. Total 56 cultures of Brucella melitensis, isolated in 1999–2019 from patients with brucellosis that permanently resided in RD, RK and SK were studied.Results. The key factor contributing to the epidemic manifestations of brucellosis in the south of the European part of Russia is the persistence of epizootic foci in cattle and small ruminants. The leading concomitant factors are as follows: the presence in the region of "hidden" epizootic foci, uncontrolled production of food products of animal husbandry and its illegal sale to customers, unauthorized movement of animals and livestock products, untimely delivery (concealment) of sick cattle for stamping out. Results of molecular analysis of B. melitensis strains indicate the circulation of a mixed population of brucella, which is generally characteristic of the entire region, without a pronounced confinement of isolates to separate administrative territories. At the same time, the entire studied sample of strains can be divided into two groups (72% and 28% of strains) based on MLVA-16 genotypes by the variability in the Bruce 19 locus, which makes it possible to associate a part of the studied strains with the territory of their isolation.Discussion. The data obtained make it possible to scientifically substantiate the possibility of considering the affected territories of the Southern Federal District and the North Caucasian Federal District as a single common persistent active anthropurgic epizootic focus with circulation of a mixed, but typical for the region population of Brucella strains.
The history of the Faculty Therapy Clinic of Sechenov University is presented. The stages of the formation of its therapeutic school are discussed. Diagnostic and therapeutic methods first developed ...and implemented in the clinic are described in detail.
•Beneficiation of the iron-oxide Nb-REM ores of the Chuktukon deposit.•Processing of the ores by direct alkaline-acid treatment and nitric acid leaching.•Direct nitric acid leaching of the REE in an ...autoclave is the most promising route.
The Chuktukon niobium-rare earth elements ore deposit is located in Siberia (Russia). Weathered carbonatite crusts are the basis of the ore deposit. The deposit itself is 3.5km in length, about 800 to 1400m in width and up to 200–300m in thickness. The ores are composed of iron-manganese oxides (hydrogoethite, hematite, psilomelane, pyrolusite) and contain 3–7wt.% of rare-earth phosphates (florencite, monazite) and 0.5–1wt.% of niobium oxide (pyrochlore). The ore is completely finely dispersed and consists of oxide particles formed of compact, dense aggregates which makes ore dressing as well as leaching of the rare and radioactive elements very difficult. Several options for processing of these ores have been considered: 1) reduction of the iron oxides to magnetite followed by beneficiation with magnetic separation to produce a rare metal concentrate; 2) processing of the rare earth elements (REE) containing minerals by direct alkaline-acid treatment; 3) processing of the ores using nitric acid leaching in an autoclave.
Aim. Determination of the degree of phylogenetic relationship of Yersinia pestis strains isolated from the territories of natural foci of plague from the Caucasus using VNTR-typing by 25 loci ...(MLVA25). Materials and methods. 26 strains of Y. pestis from Russian natural foci of the Caucasus were used in the study. 25 loci of tandem repeats in Y. pestis genome by Le Fleche scheme were used for execution of multi-locus VNTR-analysis. Deciphering of nucleotide sequences was carried out in automatic sequencer ABI 3130 Genetic Analyser. Analysis of confinement of clusters to certain territories, objects and time of isolation of strains was carried out using Arc GIS 10.1 program. Results. Groups of MLVA25-types of various levels of discrimination were formed: clusters, groups and subgroups. Clusters were formed by strains of various taxonomic membership: main and subspecies of Y. pestis. Subgroups reflect membership of strains in certain foci, and MLVA25-types - the degree of genetic relationship. Conclusion. Genetic «portraits» of plague causative agents obtained using MLVA25-types circulating in various natural-focal territories allow to solve problems ofboth theoretical and practical character: from interpretation of microevolution processes to the search of the source of infection and ways of its spread during possible epidemic complications.
The effect of the pressure of the nitrogen atmosphere during the formation of vacuum arc nitride coatings based on high entropy alloys of the Ti-Zr-Hf-V-Nb-Ta system on their structure, hardness, and ...tribotechnical characteristics is considered. It is shown that strong nitride-forming components lead to the dependence of the structural state and properties on the pressure of the nitrogen atmosphere during coating deposition. Deposition at a nitrogen pressure of 0.4 Pa results in the formation of a texture with the 111 axis when the applied bias potential is −70 V and when the bias potential is equal to −150 V the textural structure is biaxial (111 and 110) textures and high value of hardness of 51 GPa Along with that the highest value of wear resistance (under oxidizing-mechanical wear) is inherent to coatings formed under the pressure of nitrogen of 0.09 Pa. The strongest microdeformation of coating crystallites corresponds to this pressure.
This paper presents an advanced model of the frequency response of a three-phase power transformer for use in conjunction with diagnostic measurements by the method of frequency response analysis ...(FRA). The model includes high- frequency behavior of the laminated core and the insulation through taking into account the frequency dependencies of the complex permittivity of insulation materials (paper, pressboard, and oil) and of the anisotropic complex permeability of magnetic core and conductors. A lumped parameter circuit model is used to simulate the frequency response of open-circuit impedance, short-circuit impedance, and impedance between primary and secondary windings, in which the characteristics of circuit elements are calculated by means of the finite-element method. The effect of correct representation of each circuit element on the FRA response is analyzed and discussed in comparison to measurement results on a real transformer.
Noncompacted myocardium of the left ventricle (NMLV), or noncompacted cardiomyopathy, according to the World Health Organization classification is a non-classified cardiomyopathy with not fully known ...origins. This type of cardiomyopathy presents with an increased trabecularity with deep intertrabecular sinuses in the LV. NMLV exists as either isolated or together with other inherited syndromes. Clinical presentation of NMLV varies: there are asymptomatic forms, or those with progression of the disease, with heart failure, angina, thromboembolism, life-threatening ventricular rhythm disorders; in some cases, the disease manifests as sudden cardiac death. At the same time, there is a problem of NMLV decompensation, with significant impact of acute myocarditis comorbidity. The article presents a case of the female patient, whose disease presented with heart failure at the background of acute myocarditis and further onset of everything for NMLV.
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