76 research outputs found
Method for determining the characteristics of a gas-steam chp with a steam turbo drive of a compressor
A new type of maneuverable combined-cycle plant with a steam-turbine drive of a low-pressure compressor is considered. The analysis of its technological processes in the generation of electric and thermal energy in heating and non-heating periods of the year is carried out. It is shown that in heating conditions, the burning of additional fuel in the afterburner between the stages of the evaporator of the utilizer boiler provides an increase in its steam production, maneuverability, thermal and electric power of the CCGT-CHP plant. The influence of the chemical composition and thermophysical properties of natural gas on obtaining the required excess air in the combustion chamber of a combined cycle gas turbine is considered. A mathematical model of technological processes is developed. The influence of deep utilization of the heat of the flue gases of the utilizer boiler on increasing the efficiency and improving the environmental characteristics of the gas-steam plant of a thermal power plant was recorded. © 2020 Institute of Physics Publishing. All rights reserved
Virtual screening benzimidazole derivatives with the highest bioavailability
The purpose of the study was to identify benzimidazole derivatives with high oral bioavailability using SwissADME web-tool.Цель исследования - поиск биологически активных соединений среди производных бензимидазола с максимальной пероральной биодоступностью
Variability of <i>pgm</i>‑Region Genes in <i>Yersinia pestis</i> Strains from the Caspian Sandy and Adjacent Plague Foci
The aim of the study was to compare the nucleotide sequences of pgm‑region genes in Yersinia pestis strains isolated on the territory of the Caspian sandy and adjacent plague foci in 1925–2015. Materials and methods. 65 Y. pestis strains from the Caspian sandy and adjacent plague foci were used in the work. DNA isolation was performed using the PureLink Genomic DNA Mini Kit. Whole genome sequencing was conducted in Ion S5 XL System (Thermo Fischer Scientific). Data processing was carried out using Ion Torrent Suite software package 3.4.2 and NewblerGS Assembler 2.6. To compare the obtained sequences with the NCBI GenBank database, the Blast algorithm was used. The phylogenetic analysis was performed according to the data of whole genome SNP analysis based on 1183 identified SNPs. The search for marker SNPs was performed using the Snippy 4.6 program. The phylogenetic tree was constructed using the Maximum Likelihood algorithm, the GTR nucleotide substitution model. Results and discussion. The nucleotide sequences of pgm‑region genes of 65 Y. pestis strains from the Caspian sandy and adjacent plague foci have been assessed. Single nucleotide substitutions have been identified in Y. pestis strains from the Caspian sandy and Kobystan plain-foothill foci in the hmsR, astB, ybtS, ypo1944, ypo1943, ypo1936 genes, as well as a deletion of 5 bp in the ypo1945 gene, which is characteristic of strains of one of the phylogenetic lines of Y. pestis from the foci of Caucasus and Transcaucasia, isolated in 1968–2001. The data obtained can be used to differentiate Y. pestis strains from the Caspian sandy focus, as well as to establish the directions of microevolution of the plague pathogen in this region and adjacent foci
VERIFICATION OF A NUMERICAL MODEL WITH A FLOW OF AIR AERODYNAMIC PROFILE S809 FOR WIND TURBINE BLADES
В настоящей работе представлено моделирование турбулентного потока вокруг аэродинамического профиля ветряной турбины. Описаны результаты моделирования течения, получены характеристики коэффициента подъемной силы, силы сопротивления и коэффициента момента при разных углах атаки.In this paper, we use turbulent flow models around the aerodynamic profile of a wind turbine. The results of modeling the flow are described, and the characteristics of the lifting force coefficients, drag forces, and moment coefficients at different angles of attack are obtained
Caspian Sandy Natural Focus: Phylogenetic History and Origin of <i>Yersinia pestis</i> Strains
The purpose of the work was to analyze the phylogenetic relations and origin of Yersinia pestis strains isolated in different periods of epizootic activity of the Caspian sandy natural focus (CSNF) of plague in the XX–XXI centuries.Materials and methods. We used 40 Y. pestis strains from CSNF and adjacent plague foci, isolated in 1922–2015. Carried out was whole genome sequencing of 19 Y. pestis strains from CSNF. Phylogenetic analysis was performed using whole genome SNP analysis based on 1914 identified SNPs. The search for marker SNPs was conducted using the Snippy 4.6 software. The phylogenetic tree was constructed using the Maximum Likelihood algorithm, the GTR nucleotide substitution model.Results and discussion. The whole genome SNP analysis has revealed that Y. pestis strains of the medieval biovar from CSNF belong to 2.MED1 phylogenetic lineage and fall into two major branches. One of them circulated in the focus in the first half of the XX century, and the other – in the second half of the XX – early XXI centuries. It is shown that strains of the first branch were the cause of outbreaks and individual cases of plague in the CSNF in the first half of the XX century. They are closely related to strains from the Caspian North-Western steppe and Volga-Ural sandy natural plague foci, which caused numerous outbreaks with high mortality rate in the same period. Y. pestis strains from the CSNF of the second half of the XX and early XXI centuries belong to the second phylogenetic branch of the 2.MED1 line, at the node of which the strains from the Northern Aral Sea region of 1945 lay. The latter were the predecessors of all strains isolated in the CSNF after a long inter-epizootic period that occurred in the middle of the XX century. There can also be traced a genetic relation between the strains from CSNF and the Dagestan plain-foothill focus
SNP-Profiles of <i>Yersinia pestis</i> Strains of the Medieval Biovar from the Caspian Sea Region Plague Foci
The SNP-typing method based on the detection of stable genetic markers in the genome, i.e., single nucleotide polymorphisms, is successfully used for genotyping of pathogenic microorganisms and can be applied for SNP-profiling of Yersinia pestis strains and molecular-genetic certification of focal areas. The aim of the study was to determine the SNP profiles of Y. pestis strains of the medieval biovar isolated in the Caspian Sea region plague foci in 1912–2015 and to develop a method for identifying unique SNPs using the Sanger sequencing for molecular-genetic certification of these territories. Materials and methods. A comprehensive study of the phenotypic and genotypic properties of 190 Y. pestis strains from plague foci in the Caspian Sea region was carried out. Phylogenetic reconstruction by the Maximum Likelihood method (GTR model) in the SeaView 5.0.4 software was performed on the basis of 1621 SNPs identified among 50 Y. pestis strains according to WG-SNP analysis in the snippy 4.6 program. Primers for PCR amplification of the SNP loci selected as target were calculated using the Vector NTI program. Sanger sequencing of SNPs loci was conducted on an ABI PRISM 3500XL genetic analyzer (Applied Biosystems, USA). Results and discussion. According to phenotypic characteristics, all studied strains from the Caspian foci belonged to a highly virulent and epidemically significant medieval biovar of the main subspecies of Y. pestis. According to the results of the WG-SNP analysis, 9 SNP genotypes were identified based on the polymorphism of single nucleotides of 24 genes characteristic of the main phylopopulations, which include strains isolated during various periods of epidemic and epizootic activity in the Caspian plague foci. Determining of SNP genotypes of Y. pestis strains of the medieval biovar, obtained over a hundred years in the Caspian foci, creates the prerequisites for defining the canonical SNP profile (canSNP) and for developing an algorithm for molecular epidemiological monitoring of the foci in which this highly virulent biovar circulates
Experimental study of the Sb-Sn-Zn alloy system
experimental description of the SbSn-Zn system by methods scanning electron microskope and differetial scanning calorimetryexperimentální popis ternární soustavy Sb-Sn-Zn metodami skenovací elektronové mikroskopie a diferenční skenovací kalorimetrieexperimental description of the SbSn-Zn system by methods scanning electron microskope and differetial scanning calorimetr
A Universal Approach to Eliminate Antigenic Properties of Alpha-Gliadin Peptides in Celiac Disease
Celiac disease is caused by an uncontrolled immune response to gluten, a heterogeneous mixture of wheat storage proteins, including the α-gliadins. It has been shown that α-gliadins harbor several major epitopes involved in the disease pathogenesis. A major step towards elimination of gluten toxicity for celiac disease patients would thus be the elimination of such epitopes from α-gliadins. We have analyzed over 3,000 expressed α-gliadin sequences from 11 bread wheat cultivars to determine whether they encode for peptides potentially involved in celiac disease. All identified epitope variants were synthesized as peptides and tested for binding to the disease-associated HLA-DQ2 and HLA-DQ8 molecules and for recognition by patient-derived α-gliadin specific T cell clones. Several specific naturally occurring amino acid substitutions were identified for each of the α-gliadin derived peptides involved in celiac disease that eliminate the antigenic properties of the epitope variants. Finally, we provide proof of principle at the peptide level that through the systematic introduction of such naturally occurring variations α-gliadins genes can be generated that no longer encode antigenic peptides. This forms a crucial step in the development of strategies to modify gluten genes in wheat so that it becomes safe for celiac disease patients. It also provides the information to design and introduce safe gluten genes in other cereals, which would exhibit improved quality while remaining safe for consumption by celiac disease patients
Primary production within the euphotic layer of the Norwegian Sea in July 1997: measurements by different methods
Results of primary production measurements obtained by different methods are presented. These methods are radiocarbon and oxygen modifications of the flask method, as well as fluorometric procedure with a PrimProd submersible probing fluorometer (produced at the Biological Department, Moscow State University). The research was carried out during a complex expedition aboard R/V Akademik Boris Petrov to the Norwegian Sea in July, 1977. Distributions of primary production values measured by different methods were correlated with other oceanographic data. Then a comparison of obtained values by the above-mentioned methods was performed
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