50 research outputs found
MOLECULAR MARKING OF SUNFLOWER LINES WITH DIFFERENT ABILITY TO SUPPRESSION OF THE CYTOPLASMIC MALE STERILITY PHENOTYPE
Ninety five lines of sunflower genetic collection differing by their ability to suppress the CMS phenotype were molecularly marked with the use of 7 primer pairs. Using the STS marker orfH522, a sterile (PET1) cytoplasmon was identified in 79 lines, which confirmed indirectly the presence of fertility restoration genes in their genotypes. The majority of these lines also have a complex of molecular markers linked to the Rf1 gene. The HRG01, HRG02 and STS115 markers showed the best diagnostic value in revealing the Rf1 gene in the examined material. The data on allelic variation of the microsatellite loci ORS224, ORS511 and ORS799 were obtained for the first time
ПОВЫШЕНИЕ ЭФФЕКТИВНОСТИ УКРЫТИЯ ЭЛЕКТРОЛИЗЕРОВ СОДЕРБЕРГА
The Soderberg aluminum reduction technology is associated with high pollutant emissions including gaseous and poorly soluble fluorides. Currently, conventional VSS cells equipped with a standard gas skirt and a burner do not meet the modern hooding efficiency requirements. The existing technology must be upgraded in order to comply with environmental regulations. The environmentally friendly Soderberg technology implemented with an upgraded gas skirt and a fundamentally new 4-dome gas removal system ensures daily average hooding efficiency of 97,4 %.Получение алюминия на электролизерах Содерберга сопряжено с выбросами в атмосферу большого количества загрязняющих веществ, включая газообразные и плохо растворимые фториды. В настоящее время рядовые электролизеры Содерберга, оснащенные стандартным газосборным колоколом и горелочными устройствами, не отвечают современным требованиям по эффективности укрытия. Для достижения нормативных экологических требований необходима модернизация существующей технологии. Внедрение технологии экологичного Содерберга, оснащенного модернизирован- ным газосборным колоколом и принципиально новой четырехкупольной системой газоудаления, обеспечивает среднесуточную эффективность укрытия 97,4 %
Explosion propagation in inert porous media
Porous media are often used in flame arresters because of the high surface area to volume ratio that is required for flame quenching. However, if the flame is not quenched, the flow obstruction within the porous media can promote explosion escalation, which is a well-known phenomenon in obstacle-laden channels. There are many parallels between explosion propagation through porous media and obstacle-laden channels. In both cases, the obstructions play a duel role. On the one hand, the obstruction enhances explosion propagation through an early shear-driven turbulence production mechanism and then later by shock–flame interactions that occur from lead shock reflections. On the other hand, the presence of an obstruction can suppress explosion propagation through momentum and heat losses, which both impede the unburned gas flow and extract energy from the expanding combustion products. In obstacle-laden channels, there are well-defined propagation regimes that are easily distinguished by abrupt changes in velocity. In porous media, the propagation regimes are not as distinguishable. In porous media the entire flamefront is affected, and the effects of heat loss, turbulence and compressibility are smoothly blended over most of the propagation velocity range. At low subsonic propagation speeds, heat loss to the porous media dominates, whereas at higher supersonic speeds turbulence and compressibility are important. This blending of the important phenomena results in no clear transition in propagation mechanism that is characterized by an abrupt change in propagation velocity. This is especially true for propagation velocities above the speed of sound where many experiments performed with fuel–air mixtures show a smooth increase in the propagation velocity with mixture reactivity up to the theoretical detonation wave velocity
Diversity Indices of Plant Communities and Their Rhizosphere Microbiomes: An Attempt to Find the Connection
The rhizosphere community represents an “ecological interface” between plant and soil, providing the plant with a number of advantages. Despite close connection and mutual influence in this system, the knowledge about the connection of plant and rhizosphere diversity is still controversial. One of the most valuable factors of this uncertainty is a rough estimation of plant diversity. NGS sequencing can make the estimations of the plant community more precise than classical geobotanical methods. We investigate fallow and crop sites, which are similar in terms of environmental conditions and soil legacy, yet at the same time are significantly different in terms of plant diversity. We explored amplicons of both the plant root mass (ITS1 DNA) and the microbial communities (16S rDNA); determined alpha- and beta-diversity indices and their correlation, and performed differential abundance analysis. In the analysis, there is no correlation between the alpha-diversity indices of plants and the rhizosphere microbial communities. The beta-diversity between rhizosphere microbial communities and plant communities is highly correlated (R = 0.866, p = 0.01). ITS1 sequencing is effective for the description of plant root communities. There is a connection between rhizosphere communities and the composition of plants, but on the alpha-diversity level we found no correlation. In the future, the connection of alpha-diversities should be explored using ITS1 sequencing, even in more similar plant communities—for example, in different synusia
Numerical simulation of modes of combustion and detonation of hydrogen-air mixtures in porous medium in the framework of the mechanics of two-phase reaction mediums
RIAM: A Universal Accessible Protocol for the Isolation of High Purity DNA from Various Soils and Other Humic Substances
A single universal open protocol RIAM (named after Research Institute for Agricultural Microbiology) for the isolation of high purity DNA from different types of soils and other substrates (high and low in humic, clay content, organic fertilizer, etc.) is proposed. The main features of the RIAM protocol are the absence of the sorption–desorption stage on silica columns, the use of high concentrations of phosphate in buffers, which prevents DNA sorption on minerals, and DNA precipitation using CTAB. The performance of RIAM was compared with a reference commercial kit and showed very good results in relation to the purity and quantity of DNA, as well as the absence of inhibitory activity on PCR. In all cases, the RIAM ensured the isolation of DNA in quantities much greater than the commercial kit without the effect of PCR inhibition up to 50 ng DNA per reaction in a volume of 15 µL. The latter circumstance along with the ability of the protocol to extract low molecular weight DNA fractions makes the method especially suitable for those cases where quantitative assessments, detection of minor components of soil microbiota, and completeness of isolation of all DNA fractions are required
Water Stress, Cadmium, and Plant Genotype Modulate the Rhizosphere Microbiome of Pisum sativum L.
Drought and heavy metals seriously affect plant growth and the biodiversity of the associated rhizosphere microbiomes, which, in turn, could be involved in the adaptation of plants to these environmental stresses. Rhizosphere soil was collected from a three-factor pot experiment, where pea line SGE and its Cd-tolerant mutant SGECdt were cultivated under both optimal and limited water conditions and treated with a toxic Cd concentration. The taxonomic structure of the prokaryotic rhizosphere microbiome was analyzed with the high-throughput sequencing of 16S rRNA amplicon libraries. A permutation test demonstrated statistically significant effects of Cd and water stress but not of pea genotype on the rhizosphere microbiome structure. Phylogenetic isometric log-ratio data transformation identified the taxonomic balances that were affected by abiotic factors and pea genotypes. A small number of significant (log ratio [−3.0:+3.0]) and phylogenetically deep balances characterized water stress, while a larger number of weak (log ratio [−0.8:+0.8]) phylogenetically lower balances described the influence of the plant genotype. Stress caused by cadmium took on an intermediate position. The main conclusion of the study is that the most powerful factor affecting the rhizosphere microbiome was water stress, and the weakest factor was plant genotype since it demonstrated a very weak transformation of the taxonomic structure of rhizosphere microbiomes in terms of alpha diversity indices, beta diversity, and the log ratio values of taxonomic balances