SU(2) Skyrme Vortices

A regular method for constructing vortex-like solutions with cylindrical symmetry to the equations of the SU(2) Skyrme chiral model is proposed. A numerical estimate for the length density of mass is given

Multiple Conclusion Rules in Logics with the Disjunction Property

We prove that for the intermediate logics with the disjunction property any basis of admissible rules can be reduced to a basis of admissible m-rules (multiple-conclusion rules), and every basis of admissible m-rules can be reduced to a basis of admissible rules. These results can be generalized to a broad class of logics including positive logic and its extensions, Johansson logic, normal extensions of S4, n-transitive logics and intuitionistic modal logics

Exact Self-consistent Particle-like Solutions to the Equations of Nonlinear Scalar Electrodynamics in General Relativity

Exact self-consistent particle-like solutions with spherical and/or cylindrical symmetry to the equations governing the interacting system of scalar, electromagnetic and gravitational fields have been obtained. As a particular case it is shown that the equations of motion admit a special kind of solutions with sharp boundary known as droplets. For these solutions, the physical fields vanish and the space-time is flat outside of the critical sphere or cylinder. Therefore, the mass and the electric charge of these configurations are zero.Comment: 17 pages, Submitted to the International Journal of Theoretical Physic

Dynamical Toroidal Hopfions in a Ferromagnet with Easy-Axis Anisotropy

Three-dimensional toroidal precession solitons with a nonzero Hopf index, which uniformly move along the anisotropy axis in a uniaxial ferromagnet, have been found. The structure and existence region of the solitons have been numerically determined by solving the Landau-Lifshitz equation.Comment: 6 pages, 4 figure

Inference Rules in Nelson’s Logics, Admissibility and Weak Admissibility

© 2015, Springer Basel. Our paper aims to investigate inference rules for Nelson’s logics and to discuss possible ways to determine admissibility of inference rules in such logics. We will use the technique offered originally for intuitionistic logic and paraconsistent minimal Johannson’s logic. However, the adaptation is not an easy and evident task since Nelson’s logics do not enjoy replacement of equivalences rule. Therefore we consider and compare standard admissibility and weak admissibility. Our paper founds algorithms for recognizing weak admissibility and admissibility itself – for restricted cases, to show the problems arising in the course of study

Instability of coherent states of a real scalar field

We investigate stability of both localized time-periodic coherent states (pulsons) and uniformly distributed coherent states (oscillating condensate) of a real scalar field satisfying the Klein-Gordon equation with a logarithmic nonlinearity. The linear analysis of time-dependent parts of perturbations leads to the Hill equation with a singular coefficient. To evaluate the characteristic exponent we extend the Lindemann-Stieltjes method, usually applied to the Mathieu and Lame equations, to the case that the periodic coefficient in the general Hill equation is an unbounded function of time. As a result, we derive the formula for the characteristic exponent and calculate the stability-instability chart. Then we analyze the spatial structure of the perturbations. Using these results we show that the pulsons of any amplitudes, remaining well-localized objects, lose their coherence with time. This means that, strictly speaking, all pulsons of the model considered are unstable. Nevertheless, for the nodeless pulsons the rate of the coherence breaking in narrow ranges of amplitudes is found to be very small, so that such pulsons can be long-lived. Further, we use the obtaned stability-instability chart to examine the Affleck-Dine type condensate. We conclude the oscillating condensate can decay into an ensemble of the nodeless pulsons.Comment: 11 pages, 8 figures, submitted to Physical Review

Use of Levosimendan in Cardiac Anesthesiology

The authors consider the main aspects of the rational use of the novel inotropic drug levosimendan in cardiosurgical patients on the basis of the results of the trials described in the literature and on their own findings in this review. The purpose of the analysis made was to provide a rationale for the effective use of this drug. The review shows the role of the ultrasound indicator left ventricular ejection fraction, the prognostic scale EuroSCORE, and the natriuretic peptides NT-proBNP and BNP in defining indications for levosimendan administration for preoperative preparation. There are original data on the lower level of the natriuretic peptides due to levosimendan therapy. The target hemodynamic monitoring values indicating that it is essential to use levosimendan in postperfusion heart failure are discussed. It is shown that it is expedient to use levosimendan simultaneously with traditional medical measures, by taking into account the pharmacokinetic features of a calcium sensitizer. The problem of levosimendan readministration in patients operated on the heart as well is stated. That there are no clear algorithms for repeated use of the drug is shown. At the same time, possible options of this therapy in different clinical situations are given. Key words: levosimendan, cardiosurgery, heart failure

Admissible Bases Via Stable Canonical Rules

We establish the dichotomy property for stable canonical multi-conclusion rules for IPC, K4, and S4. This yields an alternative proof of existence of explicit bases of admissible rules for these logics

An integrated approach to the registration and preservation of a cultivar gene pool in the VIR genebank exemplified in cultivars bred by the Ural Federal Agrarian Research Center of the Ural Branch of the Russian Academy of Sciences

As part of a comprehensive program for registering and preserving the gene pool of Russian varieties in the VIR genebank, initiated at the N.I. Vavilov All-Russian Institute of Plant Genetic Resources, nomenclatural standards were assigned to potato cultivars ‘Alâska’, ‘Argo’, ‘Bravo’, ‘Irbitskij’, ‘Legenda’, ‘Lûks’, ‘Terra’, and ‘Šah’, and a voucher specimen was prepared for pre-cultivar ‘Bagira’. All of them were bred at the Ural Federal Agrarian Research Centre (Ural Branch of the Russian Academy of Sciences). Nomenclatural standards of these cultivars are preserved in the Nomenclatural standard collection at the Herbarium of cultivated plants and their wild relatives and weeds (VIR Herbarium, WIR). For each of them, a genetic passport was developed using DNA preparations isolated from plant material donated by the cultivar author to the VIR herbarium. The genetic passport, which includes information on the allelic composition of eight chromosome-specific microsatellite loci, is supplemented by the molecular screening data with markers of 11 R-genes for resistance to pests, as well as the data on the types of cytoplasm. The author of cultivars also supplied VIR with samples of virus-free in vitro plants. Microplants of eight Ural cultivars and one pre-cultivar were genotyped using the same SSR markers and included in the VIR in vitro collection, and then in the cryopreservation program. Most of the accessions were characterized by a relatively high, above 39%, level of post-cryogenic regeneration. Frozen explants of the genotyped Ural cultivars (‘Alâska’, ‘Argo’, ‘Legenda’, ‘Terra’, and ‘Šah’) and pre-cultivar ‘Bagira’ were placed for long-term storage in the VIR Cryobank