Universality of temperature distribution in granular gas mixtures with a steep particle size distribution

Distribution of granular temperatures in granular gas mixtures is investigated analytically and numerically. We analyze space uniform systems in a homogeneous cooling state (HCS) and under a uniform heating with a mass-dependent heating rate $\Gamma_k\sim m_k^{\gamma}$. We demonstrate that for steep size distributions of particles the granular temperatures obey a universal power-law distribution, $T_k \sim m_k^{\alpha}$, where the exponent $\alpha$ does not depend on a particular form of the size distribution, the number of species and inelasticity of the grains. Moreover, $\alpha$ is a universal constant for a HCS and depends piecewise linearly on $\gamma$ for heated gases. The predictions of our scaling theory agree well with the numerical results

Comparison of Different Fuel Compositions for a Research Reactor with Thermal Power of up to 10 MW

In this article the prospect of using carbide fuel in a research reactor for export to countries with developing nuclear power is consider. The choice of a fuel composition for a research reactor is an important part in substantiating of the neutron-physical and economic characteristics of a reactor facility, and is also an important part of the control-dependent self-sustaining fission chain reaction in a nuclear reactor that affects the specifics of management. For reducing the economic component in the design of this reactor core of the research reactor, structural materials and design solutions are used that have extensive experience in domestic power engineering. In this work UO2-ThO2 and PuO2-ThO2 was selected as the considered fuel compositions. In the course of the study, characteristics were obtained for a burnup of the fuel compositions under study, the initial reserve of reactivity and the duration of the fuel campaign

Cascades of Multi-headed Chimera States for Coupled Phase Oscillators

Chimera state is a recently discovered dynamical phenomenon in arrays of nonlocally coupled oscillators, that displays a self-organized spatial pattern of co-existing coherence and incoherence. We discuss the appearance of the chimera states in networks of phase oscillators with attractive and with repulsive interactions, i.e. when the coupling respectively favors synchronization or works against it. By systematically analyzing the dependence of the spatiotemporal dynamics on the level of coupling attractivity/repulsivity and the range of coupling, we uncover that different types of chimera states exist in wide domains of the parameter space as cascades of the states with increasing number of intervals of irregularity, so-called chimera's heads. We report three scenarios for the chimera birth: 1) via saddle-node bifurcation on a resonant invariant circle, also known as SNIC or SNIPER, 2) via blue-sky catastrophe, when two periodic orbits, stable and saddle, approach each other creating a saddle-node periodic orbit, and 3) via homoclinic transition with complex multistable dynamics including an "eight-like" limit cycle resulting eventually in a chimera state.Comment: 13 pages, 14 figure

Exchange rates: the influence of political and economic events. а fundamental analysis approach

The objective of the article is to study the influence of political and economic factors on the situation on the world foreign exchange market, substantiate the importance of fundamental analysis in forecasting currency rates. The concept and mechanisms of functioning of the world currency market, its assets and specific features in comparison with other financial platforms are considered in the article. The need for special attention to fundamental analysis during the periods of global political and economic events is grounded. Based on the analysis of the dynamics of the leading world currency pairs in recent years, the period from October 2016 to April 2017 was chosen for an analysis because that period is full of significant events in the world political and economic arena, which are powerful levers of the traders’ behavior, and hence the direction of the dynamics of key currency pairs. These events are as follows: presidential elections in the USA; two increases of the Federal Reserve rate; and the policy of the European Central Bank, aimed at stimulating inflation. It is substantiated that using the fundamental analysis makes it possible to assess the trend and scale of changes in the rates of the world currencies, and in combination with technical analysis is an integral tool for successful trading and forecasting the dynamics of currency pairs. The possibility of using the mechanisms of functioning of such fundamental analysis tool as artificial neural networks and the ways of their application in solving such problems has been considered

Canine and Human Dirofilariosis in the Rostov Region (Southern Russia)

Epidemiological data on canine and human dirofilariosis in the Rostov Region (Southern Russia) are presented. Prevalence of Dirofilaria spp. infections in 795 autochthonous dogs, assessed by the Knott test, was 20.25%. The highest prevalence was found in Novocherkassk (38.3%) and Rostov-on-Don (18.5%), while prevalences were lower in other points of the region. Prevalence of D. repens was 44.7%, prevalence of D. immitis was 30.3%, and coinfections were observed in 25.0% of the dog population. A case finding study carried out during 9 years (2000–2009) revealed 131 cases of human dirofilariosis in the Rostov Region, 129 of subcutaneous dirofilariosis and 2 of pulmonary dirofilariosis. Seroprevalence among 317 healthy blood donors from the Rostov Region was 10.4%, while seroprevalence in policemen living in Rostov city and working in training dogs was 19%. These data show high infection rates of Dirofilaria spp. in both human and dog populations of Rostov, probably because of the existence of favorable conditions for the transmission in this region

Comparative analysis of the intestinal microbiota in patients with exocrine pancreatic insufficiency of various severity

Background. Exocrine pancreatic insufficiency (EPI) is a critical host factor in determining the composition of the gut microbiota. Diseases that cause exocrine insufficiency can affect the gut microbiome, which can potentiate disease progression and complications. To date, the relationship of exocrine insufficiency in various pancreatic (PA) pathologies, in chronic pancreatitis (CP), with dysbiotic changes in the intestinal microbiota (IM) has not been reliably studied. The available data are heterogeneous and contradictory, which determines the need for further research. Aim. To conduct a comparative analysis of the taxonomic composition of the intestinal microbiota in patients with CP of various etiologies, without or with the presence of EPI of varying severity, as well as patients with severe EPI with a history of surgical intervention (SI) on the pancreas. Materials and methods. A total of 85 patients were included in the study. Patients were divided into groups according to the severity of EPI: Group 1 (n=16) patients with CP without EPI; Group 2 (n=11) patients with CP and mild EPI; Group 3 (n=17) patients with severe CP and EPI; Group 4 (n=41) severe EPI in persons with a history of SI on the pancreas. Verification of CP was carried out according to clinical, anamnestic and instrumental data. The degree of EPI was determined by the level of pancreatic elastase-1 (PE-1) feces. Informed consent for the study was obtained for each patient, an anamnesis was collected, physical and laboratory examinations were performed, and a stool sample was obtained. DNA was extracted from each stool sample, the taxonomic composition of BM was determined by sequencing the bacterial 16S rRNA genes, followed by bioinformatic analysis. Results. We followed the changes in the gut microbiota from a group of patients with CP without EPI to a group with severe EPI, in those who underwent SI. At the level of the phylum, the IM of all groups showed the dominance of Firmicutes, with the lowest representation in the severe EPI group, both with SI and CP, and the growth of the Actinobacteria, Verrucomicrobiota and Fusobacteria types. The differential representation of childbirth varied: in patients with severe EPI and CP, compared with mild, statistically significant genera Akkermansia, Ruminococcus gauvreauii group and Holdemanella; compared with CP without exocrine insufficiency, Prevotella, Ruminococcus gauvreauii group, Peptostreptococcus and Blautia dominated. The CP group with mild EPI was dominated by the following genera: Lachnospiraceae_ND 2004 group, Faecalitalea, Fusobacterium, Catenibacterium, Roseburia, Atopobium, Cloacibacillus, Clostridium innococum group, Ruminococcus torques group. All groups showed a low diversity of taxa with a predominance of opportunistic flora, including participants in oncogenesis. Conclusion. The results of the study show that patients with CP of various etiologies and patients with severe EPI who underwent specific intervention on the pancreas have intestinal microbiota dysbiosis, the severity of which is significantly influenced by the degree of EPI