On Control Problem with Constraints of Asymptotic Character

For the double integrator with a discontinuous coefficient at the control, we obtain an attraction set—an asymptotic variant of reachable sets corresponding to constraints of asymptotic character—and study the latter’s properties. These constraints correspond to a control mode in the class of short-time pulses. An additional requirement is to fully consume the available energy resources. To calculate the attraction set numerically, an algorithm was developed and implemented. The results of computational experiments are presented

On reachable sets for one-pulse controls under constraints of asymptotic character

We study asymptotic versions of reachable sets of linear systems for two intuitive formalizations of onepulse controls given constraints of asymptotic character. The results are presented for the simplest example of linear control systems, the double integrator, though they admit a straightforward extension to a generic linear system. We suppose that the coefficient at the control is a piecewise continuous function. To illustrate the developed theoretical framework for both formalizations, we demonstrate examples of linear control systems, the double integrator, though they admit a straightforward extension to a generic linear system. We suppose that the coefficient at the control is a piecewise continuous function. To illustrate the developed theoretical framework for both formalizations, we demonstrate examples of attraction sets, asymptotic versions of reachable sets

Proton and carbon-ion minibeam therapy: from modeling to treatment

Arrays of minibeams of protons and $^{12}$C in tissue-like media were modeled with Geant4 toolkit. A set of beam energies was used in simulations to provide a Spead-out Bragg peak (SOBP) extended by 6 cm in depth for protons as well as for $^{12}$C. In both cases, beams of 0.3 mm or 0.5 mm FWHM were arranged at the entrance to a water phantom either on a rectangular or an hexagonal grid to compare two kinds of projectiles and different minibeam patterns. Differential and cumulative dose-volume histograms (DVH) were calculated and compared for protons and $^{12}$C as dose uniformity metrics. A uniform dose distribution was easily achieved with protons due to an enhanced lateral scattering of these projectiles in comparison to $^{12}$C. The cumulative DVHs calculated for 0.3 mm or 0.5 mm minibeams almost coincide in the target volume, but diverge for different grid patterns. In contrast, cumulative entry DVHs were found similar for both grid patterns, but different for 0.3 mm and 0.5 mm minibeams.Comment: 8 pages, 5 figures, talk given at the XXV International Baldin Seminar on High Energy Physics Problems "Relativistic Nuclear Physics and Quantum Chromodynamics", September 18-23, 2023, Dubna, Russi

Characterization of the core bacteriobiome in the rhizosphere of greenhouse vegetables: taxonomic diversity and putative functions

The aim of the study. The aim was to profile 16S rRNA gene diversity and to assess functional potential of bacterial assemblages in the rhizosphere of some unconventional vegetables grown in protected greenhouse conditions in West Siberia. Location and time of the study. Novosibirsk, Russia, 2016. Methodology. At the end of the growing season in the middle of September the rhizosphere soil was collected from the plants of wax gourd (Benincasa hispida), bitter melon (Momordica charantia), kiwano (Cucumis metuliferus) and cowpea (Vigna unguiculata) grown on peat-based substrate in a polyethylene-protected greenhouse that has been in operation for more than 40 years. The metagenomic DNA was extracted and amplified with V3-V4 primers for 16S rRNA genes, and the amplicons sequenced with Illumina MiSeq. The obtained OTUs tables were used to predict putative functions by running through the FAPROTAX database. Main results. The rhizosphere bacteriobiome was dominated by Proteobacteria (32±11% of the total number of sequence reads), Acidobacteria (23±7%) and Actinobacteria (18±3%) phyla, together accounting for about three quarters of the rhizosphere bacteriobiome. In total 20 bacterial phyla were found. The rhizosphere bacteriobiome was surprisingly diverse with Shannon index ranging 7.0–7.5. The number of the observed operational taxonomic units (OTUs) per sample was very high, ranging 4,500–4,900, and the potential number of OTUs estimated as 5,100–5,700; all those OTUs were evenly and equitably represented in the bacteriobiome, and dominance indices (Simpson dominance and Berger-Parker) were very low. The main dominant OTU represented Bradyrhizobiaceae family and accounted for just 1% on average. Overall the study identified 27 OTUs belonging to the Bradyrhizobiaceae family, but only four of them were ascribed to nitrogen fixation by FAPROTAX. Function prediction by FAPROTAX also suggested that bacteriobiome had a marked potential for the carbon cycle, denitrification, aromatic compound and plant polymer degradation, but no plant pathogens. The biggest difference in rhizosphere bacteriobiome diversity was observed between the bitter melon and the other three vegetable crops: bitter melon had much increased abundance of Arthrobacter and Sphingomonas as compared with wax gourd, kiwano and cowpea, and increased number of bacterial species associated with aromatic compounds degradation. Conclusion. Based on the finding that the studied rhizosphere bacteriobiomes were very diverse, we conclude that the crops were able to recruit diverse microbiota from the peat-based soil substrate, which, in its turn, means that diverse soil substrate microbiota has been sustained over several decades of the greenhouse operation. All crops apparently shaped distinct bacteriobiomes in their rhizosphere, which ideally should be included into studies of plant-associated bacterial diversity profiles for breeding and sustainable production.The aim of the study. The aim was to profile 16S rRNA gene diversity and to assess functional potential of bacterial assemblages in the rhizosphere of some unconventional vegetables grown in protected greenhouse conditions in West Siberia. Location and time of the study. Novosibirsk, Russia, 2016. Methodology. At the end of the growing season in the middle of September the rhizosphere soil was collected from the plants of wax gourd (Benincasa hispida), bitter melon (Momordica charantia), kiwano (Cucumis metuliferus) and cowpea (Vigna unguiculata) grown on peat-based substrate in a polyethylene-protected greenhouse that has been in operation for more than 40 years. The metagenomic DNA was extracted and amplified with V3-V4 primers for 16S rRNA genes, and the amplicons sequenced with Illumina MiSeq. The obtained OTUs tables were used to predict putative functions by running through the FAPROTAX database. Main results. The rhizosphere bacteriobiome was dominated by Proteobacteria (32±11% of the total number of sequence reads), Acidobacteria (23±7%) and Actinobacteria (18±3%) phyla, together accounting for about three quarters of the rhizosphere bacteriobiome. In total 20 bacterial phyla were found. The rhizosphere bacteriobiome was surprisingly diverse with Shannon index ranging 7.0–7.5. The number of the observed operational taxonomic units (OTUs) per sample was very high, ranging 4,500–4,900, and the potential number of OTUs estimated as 5,100–5,700; all those OTUs were evenly and equitably represented in the bacteriobiome, and dominance indices (Simpson dominance and Berger-Parker) were very low. The main dominant OTU represented Bradyrhizobiaceae family and accounted for just 1% on average. Overall the study identified 27 OTUs belonging to the Bradyrhizobiaceae family, but only four of them were ascribed to nitrogen fixation by FAPROTAX. Function prediction by FAPROTAX also suggested that bacteriobiome had a marked potential for the carbon cycle, denitrification, aromatic compound and plant polymer degradation, but no plant pathogens. The biggest difference in rhizosphere bacteriobiome diversity was observed between the bitter melon and the other three vegetable crops: bitter melon had much increased abundance of Arthrobacter and Sphingomonas as compared with wax gourd, kiwano and cowpea, and increased number of bacterial species associated with aromatic compounds degradation. Conclusion. Based on the finding that the studied rhizosphere bacteriobiomes were very diverse, we conclude that the crops were able to recruit diverse microbiota from the peat-based soil substrate, which, in its turn, means that diverse soil substrate microbiota has been sustained over several decades of the greenhouse operation. All crops apparently shaped distinct bacteriobiomes in their rhizosphere, which ideally should be included into studies of plant-associated bacterial diversity profiles for breeding and sustainable production

Development of High Granulated Straw Chambers of Large Sizes

We have developed the baseline design for the straw drift tube tracking detectors for high rate environment application. The low-mass inner straw elements and the technology of the multianode straws assembly was devised and checked. The prototype chamber was constructed and studied the granularity of similar chambers can be reduced to one cm2. Submitted to Physics of Elementary Particles and Atomic Nuclei, LettersComment: 6 pages, 10 figure

Modeling of ammonia oxidation on a platinoid catalyst, taking into account the N₂O formation

A mathematical model of ammonia oxidation on a platinoid catalyst, taking into account the N₂O formation, was developed. The possibilities of lowering the amount of N₂O, which is formed as by-product in high-temperature oxidation of ammonia in nitric acid production, are examined. The developed model allows calculation of the reactor for ammonia oxidation using platinoid catalysts of different geometric profiles

Development of metacognitive competencies of students in the process of constructing mathematical problems for younger students

The article presents a description of the study of the effectiveness of methodological tools aimed at developing metacognitive competence in future elementary school teachers in the classroom on the methodology of teaching mathematics to younger students.The aim of the study is to empirically test the effectiveness of a set of methodological techniques used in the classroom on the methodology of teaching mathematics to future elementary school teachers as a means of developing their metacognitive competencies. The hypothesis of the study is the assumption that one of the effective means of developing metacognitive competencies in future elementary school teachers is special classes for compiling original scenarios of verbal mathematical problems for younger students. A professionally developed verbal composition of a mathematical problem sets the vector of mental activity for the younger student. It requires the developer to build a forecast of the child’s mental actions, determine algorithms and levels of difficulty in obtaining the right solution. The study used methods for testing students’ cognitive characteristics (intelligence) and peer review of their “metacognitive knowledge”, “metacognitive skills”, “metacognitive experience” and “metacognitive strategies”. The methodological solutions implemented in the classroom have shown their effectiveness. For the practice of preparing future primary school teachers, it is important that the well-organized development of compositions of textual mathematical problems for younger students is an effective means of developing their metacognitive competencies

П'ята міжнародна наукова-практична конференція «Комп’ютерне моделювання в хімії і технологіях та системах сталого розвитку»

Розроблена кінетична модель селективного каталітичного відновлення NOx амоніаком на церій-вмістних змішаних оксидних каталізаторах. Кінетична модель, що враховує зовнішньодифузійне гальмування, розроблена на основі комплексу експериментальних даних. Аналіз експериментальних даних показав значний вплив концентрацій NOx и NH3 на ступінь конверсії за різних температур та часу контакту. Зіставлення експериментальних та розрахункових даних показало добру збіжність.A kinetic model for the selective catalytic reduction of NOx with NH3 over a Ce-content mixed-oxide catalyst was developed. A kinetic model which includes the effect of washcoat diffusion limitations is developed on the basis of experimental observations. Analysis of experimental data indicated that feed concentrations of NOx and NH3 had significant effects on the NOx conversion. The model was constructed from a range of reactant concentrations and temperatures. The model could describe all validation experiments very well. A good agreement is obtained between the experimental observations and the model predictions.Разработана кинетическая модель селективного каталитического восстановления NOx аммиаком на церий-содержащих смешанных оксидных катализаторах. Кинетическая модель, учитывающая эффект внешнедиффузионного торможения, разработана на основе комплекса экспериментальных данных. Анализ экспериментальных данных показал значительное влияние концентраций NOx и NH3 на степень конверсии при разных температурах и времени контакта. Сопоставление экспериментальных и расчетных данных показывает хорошую сходимость