94 research outputs found

    State-to-State Kinetic Theory Approach for Transport and Relaxation Processes in Viscous Reacting Gas Flows

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    Abstract. In the paper, the description of non-equilibrium reacting gas flows taking into account detailed vibrational and chemical kinetics is considered on the basis of the kinetic theory methods. The kinetic models for transport and relaxation processes are presented, and peculiar features of transport coefficients in the state-to-state approach for reacting flows are demonstrated. Contribution of different dissipative processes to the diffusion velocity and heat flux is discussed. The statedependent rate coefficients for vibrational energy transitions, dissociation, recombination and exchange chemical reactions are studied in the zero-and first-order approximations of modified Chapman-Enskog method. Practical applications of proposed models for non-equilibrium gas-dynamics problems are discussed

    State-to-State Kinetic Theory Approach for Transport and Relaxation Processes in Viscous Reacting Gas Flows

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    Abstract. In the paper, the description of non-equilibrium reacting gas flows taking into account detailed vibrational and chemical kinetics is considered on the basis of the kinetic theory methods. The kinetic models for transport and relaxation processes are presented, and peculiar features of transport coefficients in the state-to-state approach for reacting flows are demonstrated. Contribution of different dissipative processes to the diffusion velocity and heat flux is discussed. The statedependent rate coefficients for vibrational energy transitions, dissociation, recombination and exchange chemical reactions are studied in the zero-and first-order approximations of modified Chapman-Enskog method. Practical applications of proposed models for non-equilibrium gas-dynamics problems are discussed

    Phylogenetic and structural analysis of annexins in pea (<i>Pisum sativum</i> L.) and their role in legume-rhizobial symbiosis development

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    Annexins as Ca2+/phospholipid-binding proteins are involved in the control of many biological processes essential for plant growth and development. In a previous study, we had shown, using a proteomic approach, that the synthesis of two annexins is induced in pea roots in response to rhizobial inoculation. In this study, phylogenetic analysis identified these annexins as PsAnn4 and PsAnn8 based on their homology with annexins from other legumes. The modeling approach allowed us to estimate the structural features of these annexins that might influence their functional activity. To verify the functions of these annexins, we performed comparative proteomic analysis, experiments with calcium influx inhibitors, and localization of labeled proteins. Essential down-regulation of PsAnn4 synthesis in a non-nodulating pea mutant P56 (sym10) suggests an involvement of this annexin in the rhizobial symbiosis. Quantitative RT-PCR analysis showed that PsAnn4 was upregulated at the early stages of symbiosis development, starting from 1–3 days after inoculation to up to 5 days after inoculation, while experiments with the Ca2+ channel blocker LaCl3 revealed its negative influence on this expression. To follow the PsAnn4 protein localization in plant cells, it was fused to the fluorophores such as red fluorescent protein (RFP) and yellow fluorescent protein (YFP) and expressed under the transcriptional regulation of the 35S promoter in Nicotiana benthamiana leaves by infiltration with Agrobacterium tumefaciens. The localization of PsAnn4 in the cell wall or plasma membrane of plant cells may indicate its participation in membrane modification or ion transport. Our results suggest that PsAnn4 may play an important role during the early stages of pea-rhizobial symbiosis development

    Pharmacological correction of the sequelae of acute alcohol-induced myocardial damage with new derivatives of neuroactive amino acids coupled with the blockade of the neuronal NO synthase isoform

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    Acute alcohol intoxication (AAI) induces a number of myocardial disorders, which result in mitochondrial dysfunction in cardiomyocytes, oxidative stress, and decreased cardiac contractility. Nitric oxide produced by the nNOS is one of the major modulators of cardiac activity. New derivatives of GABA (RSPU-260 compound) and glutamate (glufimet) can be potentially regarded as such agents as the interaction between the NO system and the GABA and glutamatergic systems has been prove

    Pharmacological correction of the sequelae of acute alcohol-induced myocardial damage with new derivatives of neuroactive amino acids coupled with the blockade of the neuronal NO synthase isoform

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    Introduction: Acute alcohol intoxication (AAI) induces a number of myocardial disorders, which result in mitochondrial dysfunction in cardiomyocytes, oxidative stress, and decreased cardiac contractility. Nitric oxide produced by the nNOS is one of the major modulators of cardiac activity. New derivatives of GABA (RSPU-260 compound) and glutamate (glufimet) can be potentially regarded as such agents as the interaction between the NO system and the GABA and glutamatergic systems has been proved. Materials and methods: All the studies were performed on female white Wistar rats, aged 10 months, whose weight was 280–320g AAI intoxication was modeled of 32% ethanol (gavage, 4g/kg). Results and discussion: Glufimet and the RSPU-260 compound caused a significant improvement in myocardial contractility, increased oxygen consumption in the V3 state according to Chance, raised the respiratory control ratio and decreased the intensity of LPO intensity. Their effectiveness exceeded that of mildronate, their comparator. nNOS inhibition resulted in a pronounced aggravation of oxidative stress implicated in MDA accumulation in cardiac mitochondria and decreased activity of SOD; myocardial contractility and mitochondrial function indicators did not show a significant difference from the control group. The compounds under study coupled with nNOS inhibition had a cardioprotective effect. Conclusion: Glufimet and the RSPU-260 compound, derivatives of neuroactive amino acids, have a pronounced cardioprotective effect, restrict LPO processes, enhance SOD activity, improve the mitochondrial respiratory function after acute alcohol intoxication when coupled with neuronal NO-synthase inhibition, the expression of which persists after AAI. Graphical abstract

    Modern Approaches to the Diagnosis and Management of Children With Primary Ciliary Dyskinesia

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    The article presents the most modern positions of healthcare delivery for children with primary ciliary dyskinesia. Symptoms of this pathology in clinical practice vary that is conditioned by genetic heterogeneity of the disease. The most common disease manifestation in children is frequent inflammatory diseases of the upper and lower respiratory tract. They are recorded in most patients, especially in young children, and the diagnosis is often determined untimely due to a low awareness of specialists about this nosology. Differential diagnostic approach is described in detail, peculiarities of treatment and management of children with this nosology are specified. The material is based on clinical guidelines developed and approved by the professional association «Union of Pediatricians of Russia»

    Современные подходы к диагностике и ведению детей с первичной цилиарной дискинезией

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    The article presents the most modern positions of healthcare delivery for children with primary ciliary dyskinesia. Symptoms of this pathology in clinical practice vary that is conditioned by genetic heterogeneity of the disease. The most common disease manifestation in children is frequent inflammatory diseases of the upper and lower respiratory tract. They are recorded in most patients, especially in young children, and the diagnosis is often determined untimely due to a low awareness of specialists about this nosology. Differential diagnostic approach is described in detail, peculiarities of treatment and management of children with this nosology are specified. The material is based on clinical guidelines developed and approved by the professional association «Union of Pediatricians of Russia».В статье представлены самые современные позиции оказания медицинской помощи детям с первичной цилиарной дискинезией. Симптомы данной патологии в клинической практике варьируют, что обусловлено генетической неоднородностью заболевания. Наиболее распространенное проявление болезни у детей — частые воспалительные заболевания верхних и нижних дыхательных путей, которые регистрируются у большинства пациентов, особенно у детей раннего возраста, а при невысокой осведомленности специалистов о данной нозологии диагноз зачастую устанавливается несвоевременно. Подробно изложен дифференциальный диагностический подход, указаны особенности лечения и ведения пациентов детского возраста с данной нозологией. Материал основан на клинических рекомендациях, разработанных и утвержденных профессиональной ассоциацией «Союз педиатров России»
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