28 research outputs found
Kink-antikink vortex transfer in periodic-plus-random pinning potential: Theoretical analysis and numerical experiments
The influence of random pinning on the vortex dynamics in a periodic square
potential under an external drive is investigated. Using theoretical approach
and numerical experiments, we found several dynamical phases of vortex motion
that are different from the ones for a regular pinning potential. Vortex
transfer is controlled by kinks and antikinks, which either preexist in the
system or appear spontaneously in pairs and then propagate in groups. When
kinks and antikinks collide, they annihilate.Comment: 4 pages, 4 figure
Torsion free groups with indecomposable holonomy group I
We study the torsion free generalized crystallographic groups with the
indecomposable holonomy group which is isomorphic to either a cyclic group of
order or a direct product of two cyclic groups of order .Comment: 22 pages, AMS-Te
Influence of parameters of delayed asphalt coking process on yield and quality of liquid and solid-phase products
Paper studies the effect of excess pressure during delayed coking of asphalt, obtained by propane deasphaltization of tar, on yield and physical and chemical properties of hydrocarbon fuels' components and solid-phase product – petroleum coke. Asphalt was coked at a temperature of 500 °C and excess pressure of 0.15-0.35 MPa in a laboratory unit for delayed coking of periodic action. Physical and chemical properties of raw materials and components of light (gasoline), medium (light gasoil), and heavy (heavy gasoil) distillates obtained during experimental study were determined: density, viscosity, coking ability, sulfur content, iodine number, pour points, flash points, fluidity loss and fractional composition. Quantitative group hydrocarbon and microelement compositions and properties of obtained samples of petroleum coke (humidity, ash content, volatiles' yield, sulfur content, etc.) were also studied. Comparative assessment of their quality is given in accordance with requirements of GOST 22898-78 “Low-sulfur petroleum coke. Specifications”. In addition, patterns of changes in excess coking pressure on yield and quality indicators of distillate products and petroleum coke were revealed. With an increase in excess pressure of coking process from 0.15 to 0.35 MPa, content of paraffin-naphthenic hydrocarbons in light and heavy gasoils of delayed coking decreases. Common pattern in asphalt coking is an increase in yield of coke and hydrocarbon gas with an increase in excess pressure from 0.15 to 0.35 MPa
DISTRIBUTION OF BIOCHEMICAL AND MOLECULAR-GENETIC MARKERS OF GENES IN WORKERS OF COAL MINING ENTERPRISES OF KUZBASS REGION SUFFERING FROM CHRONIC DUST BRONCHITIS
Distribution of genotypes of biochemical markers of HP, GC, EsD, АсР genes, genotypes on polymorphic variants of the genes coding enzymes of biotransformation GSTT1 (GST-ɵ1) and GSTM1 (GST-μ1) and NOS3 (VNTR4 polymorphism) in the miners with chronic mechanic bronchitis, and in persons without this occupational pathology is investigated. It is shown that the owners of EsD 1-2, АсР bb genotypes are most subject to development of chronic mechanic bronchitis. Endogen factors of resistance to this disease are GC 1-1, EsD 1-1, АсР bc genotypes
HOST GENETICS OF SUSCEPTIBILITY Mutations in genes underlying atypical familial mycobacteriosis are not found in tuberculosis patients from Siberian populations
s u m m a r y Objectives: Atypical familial mycobacteriosis (AFM, OMIM #209950) is caused by mutations in genes regulating IL12/IFNG pathway. Some of the mutations exhibit incomplete penetrance, and they have been proposed to be involved in the common (polygenic) predisposition to tuberculosis (TB). We set out to test this hypothesis in two populations from Siberian region of Russia with high prevalence of TB. Material and methods: The prevalence of twelve mutations in IL12/IFNG pathway genes of were analysed in 331 Russians and 238 Tuvinians TB patients and in 279 healthy Russians and 265 healthy Tuvinians. A screening for new mutations and rare polymorphisms was carried out in 10 children with severe generalized TB and severe BCG-vaccine complications using Sanger's bidirectional sequencing. Results: Twelve mutations most commonly identified in AFM patients appeared to be "wild-type" monomorphic in the studied groups. No new mutations or rare polymorphisms were identified by sequencing. However, 15 common single nucleotide polymorphisms were found, none of which was associated with TB after correction for multiple testing. Conclusion: The results of the study contradict with a hypothesis that mutations underlying AFM syndrome are involved in the predisposition to TB
Стресс-индуцированная дисфункция тромбоцитов у крыс с фолат-зависимой гипергомоцистеинемией
A rat model of experimental hyperhomocysteinemia (HHC) caused by chronic folic acid deficiency was used to study the impact of swimming stress on the values of agonist-induced platelet aggregation and ATP release. At week 8 of HHC development, platelet aggregability and ATP levels in response to test inductors (ADP, thrombin, and collagen) moderately increased. After stress, the rate of platelet aggregation showed a more increase in rats with HHC; however, the increment was less pronounced than in the control group. The similar changes was observed in ATP, the release of which from dense platelet granules decreased in the experimental animals exposed to stress changes as compared to the controls. The experimental findings suggest that the stress potentiates platelet dysfunction in HHC. На модели экспериментальной гипергомоцистеинемии (ГГЦ) у крыс, вызванной хроническим дефицитом в организме фолиевой кислоты, изучалось влияние плавательного стресса на показатели агонист-индуцированной агрегации тромбоцитов и реакцию высвобождения из них АТФ. Показано, что на восьмой неделе развития ГГЦ агре-гационная способность тромбоцитов, как и уровень АТФ на все исследованные индукторы (АДФ, тромбин, коллаген), умеренно повышались. После стрессовой нагрузки интенсивность агрегации тромбоцитов у крыс с ГГЦ еще более возрастала, однако прирост ее был менее выраженным, чем в контрольной группе. Аналогичная динамика зарегистрирована со стороны АТФ, выброс которого из плотных тромбоцитарных гранул опытных животных, подвергнутых стрессу, уменьшался по сравнению с контролем. Результаты экспериментов свидетельствуют о потенцирующем влиянии стресса на дисфункцию тромбоцитов при ГГЦ.
ANALYSIS OF ASSOCIATIONS OF POLYMORPHOUS VARIANTS OF GENES-CANDIDATES OF MULTI-FACTORIAL DISEASES WITH PULMONARY TUBERCULOSIS
The articles presents results of associative study of pulmonary tuberculosis and 17 genes with the wide competence field, which products are informative in relations to development of multi-factorial diseases of various etiology. The biggest number of associations was found out to the gene of NOS3 (in particular with rs1799983) – they were registered as associations with pulmonary tuberculosis in general (p = 0.003), and with its clinical forms (p = 0.006), tissue destruction level (p = 0.029), endophenotypes (0.002 ≤ p ≤ 0.033 for various clinical manifestations). The following combinations of genotypes of VNTR/rs1799983 are generally associated with studied pathology (gene of NOS3), rs3746190/rs11575926 (gene of IL12RB1), rs909253/rs1800629 (gene LTA/TNF). Moreover the following polymorphous variants of genes are associated with qualitative and quantitative signs of pulmonary tuberculosis: TNF, LTA, TNFRSF1B, IL12RB1, IFNGR2, ADRB2, IL4R, GNB3. The associative study of genes of GNB3, PPP3R1, GATA4 with tuberculosis was conducted for the first time