Vortex-chain phases in layered superconductors

Layered superconductors in tilted magnetic field have a very rich spectrum of vortex lattice configurations. In the presence of in-plane magnetic field, a small c-axis field penetrates in the form of isolated vortex chains. The structure of a single chain is mainly determined by the ratio of the London [$\lambda$] and Josephson [$\lambda_{J}$] lengths, $\alpha= \lambda/\lambda_{J}$. At large $\alpha$ the chain is composed of tilted vortices [tilted chains] and at small $\alpha$ it consists of a crossing array of Josephson vortices and pancake stacks [crossing chains]. We studied the chain structures at intermediate $\alpha$'s and found two types of behavior. (I) In the range $0.4 < \alpha < 0.5$ a c-axis field first penetrates in the form of pancake-stack chains located on Josephson vortices. Due to attractive coupling between deformed stacks, their density jumps from zero to a finite value. With further increase of the c-axis field the chain structure smoothly evolves into modulated tilted vortices and then transforms via a second-order phase transition, into the tilted straight vortices. (II) In the range $0.5 < \alpha < 0.65$ a c-axis field first penetrates in the form of kinks creating kinked tilted vortices. With increasing the c-axis field this structure is replaced via a first-order phase transition by the strongly deformed crossing chain. This transition is accompanied by a large jump of pancake density. Further evolution of the chain structure is similar to the higher anisotropy scenario: it smoothly transforms back into the tilted straight vortices.Comment: Accepted to Phys. Rev. B, 20 pages 12 figures, animation of chain structure is available in http://mti.msd.anl.gov/movies/Chains/Nl8al06Im.gif (gif, 441 KB

REGULATORY ISSUES OF THE SMALL AGRICULTURAL FARMING DEVELOPMENT

It is noted that the opportunities of the small-scale agricultural sector are not being used in full force. There are signicant diculties in starting and further developing small farming in lending, risk insurance, logistics, innovative modernization and especially in the segment of sales of products. The increment of scientic knowledge carries in itself the precise denition of small agrarian forms of farming, as well as the economic mechanism of the process of regulating the development of small-scale economic entities. Particular attention is paid to the procedure of independent and transparent receipt of subsidies for increasing the investment activity in the development of small forms of farming

Influence of Administrative Regulation on the Efficiency of Business Activities in the Region

The article discusses the theoretical issues of the formation of the administrative regulation mechanisms for business entities. The necessity of the further development of theoretical and methodological base and the application tools for the design of business environment is proved. This can stimulate the growth of business and investment activity in the Russian regions and municipalities. The authors identify two types of government structures influence on the business entities, differentiated by the nature of the targeting impact on the economic activity of business structures—the administrative pressure and administrative assistance. It is suggested that in practice, high cost implications for compliance with all regulation requirements as well as sanctions for the violation of these requirements create preconditions for the development of informal interaction between entrepreneurs and the representatives of regulatory bodies. Therefore, businessmen try to minimize the costs associated with the implementation of formal administrative requirements, rules and regulations by personal arrangements. A mathematical model for the assessment of the informal interaction between business entities and certain officials of control supervisory authorities is proposed. It allows to determine the range of benefits for economic entities from avoiding the implementation of administrative norms, requirements and rules. It is concluded that unreasonably high level of costs for the implementation of formal administrative requirements rules and regulations by business entities composes the economic basis for the reproduction of informal relations. This determines mutual benefits for a number of entrepreneurs and a part of bureaucracy from various schemes of informal interaction.The article has been prepared with the support of the Grant of the Russian Foundation for Humanities in the framework of the research and development project " Development of a favourable institutional configuration of the regional business environment as the factor to increase the competitiveness of business entities" No. 16–12–02007

Program for experimental investigations of the mechanisms for the emission of coherent radiation by relativistic electrons with energies of 10-500 MeV in oriented crystals

A program of experimental investigations of the mechanisms for the emission of coherent radiation by electrons in periodic structures is proposed. The program is aimed at developing sources of energy-tunable quasimonochromatic x radiation and y radiationyesBelgorod State Universit

On the research of the methodology of mathematization of pedagogical science

Topicality of the study is driven by the fact that the new fundamental mathematical ideas and methods of mathematics arise in the new era of mathematization of science and have a great influence on the formation of methodological culture of educational research in recent decades. The aim of the article is to identify the important aspects of the methodology of mathematization of pedagogical science. The leading approach to the study of this problem is a philosophical and mathematical analysis of aspects of the methodology of mathematization of pedagogical science that allows to consider in complex the aspects revealing in the light of matematization of sciences. The analysis of the specified aspects describes the main features of a methodological interaction between mathematical and pedagogical science, the influence of the ideas and methods of modern mathematics and mathematical culture on pedagogical research, on the formation of conceptual and terminological bases of correct logic and of the reasoning of pedagogical research. The materials of the article can be used in the correct use of ideas and methods of modern mathematics during the study of the characteristic features of pedagogical objects, processes and phenomena. © 2016 Perminov et al

Kinetics of the thermal degradation of Erica arborea by DSC: Hybrid kinetic method

The scope of this work was the determination of kinetic parameters of the thermal oxidative degradation of a Mediterranean scrub using a hybrid method developed at the laboratory. DSC and TGA were used in this study under air sweeping to record oxidative reactions. Two dominating and overlapped exothermic peaks were recorded in DSC and individualized using an experimental and numerical separation. This first stage allowed obtaining the enthalpy variation of each exothermic phenomenon. In a second time, a model free method was applied on each isolated curve to determine the apparent activation energies. A reactional kinetic scheme was proposed for the global exotherm composed of two independent and consecutive reactions. In fine mean values of enthalpy variation and apparent activation energy previously determined were injected in a model fitting method to obtain the reaction order and the preexponential factor of each oxidative reaction. We plan to use these data in a sub-model to be integrated in a wildland fire spread model

Stabilization of a-conotoxin AuIB: influences of disulfide connectivity and backbone cyclization

a-Conotoxins are peptides isolated from the venom ducts of cone snails that target nicotinic acetylcholine receptors (nAChRs). They are valuable pharmacological tools and have potential applications for treating a range of conditions in humans, including pain. However, like all peptides, conotoxins are susceptible to degradation, and to enhance their therapeutic potential it is important to elucidate the factors contributing to instability and to develop approaches for improving stability. AuIB is a unique member of the a-conotoxin family because the nonnative &quot;ribbon&quot; disulfide isomer exhibits enhanced activity at the nAChR in rat parasympathetic neurons compared with the native &quot;globular&quot; isomer. Here we show that the ribbon isomer of AuIB is also more resistant to disulfide scrambling, despite having a nonnative connectivity and flexible structure. This resistance to disulfide scrambling does not correlate with overall stability in serum because the ribbon isomer is degraded in human serum more rapidly than the globular isomer. Cyclization via the joining of the N- and C-termini with peptide linkers of four to seven amino acids prevented degradation of the ribbon isomer in serum and stabilized the globular isomers to disulfide scrambling. The linker length used for cyclization strongly affected the relative proportions of the disulfide isomers produced by oxidative folding. Overall, the results of this study provide important insights into factors influencing the stability and oxidative folding of a-conotoxin AuIB and might be valuable in the design of more stable antagonists of nAChRs