Statistical physics of dyons and quark confinement

We present a semiclassical approach to the SU(N) Yang--Mills theory whose partition function at nonzero temperatures is approximated by a saddle point -- an ensemble of an infinite number of interacting dyons of N kinds. The ensemble is governed by an exactly solvable 3d quantum field theory, allowing calculation of correlations functions relevant to confinement. We show that known criteria of confinement are satisfied in this semiclassical approximation: (i) the average Polyakov line is zero below some critical temperature, and nonzero above it, (ii) a quark-antiquark pair has linear rising potential energy, (iii) the average spatial Wilson loop falls off exponentially with the area, (iv) N^2 gluons are canceled out from the spectrum, (v) the critical deconfinement temperature is in good agreement with lattice data. Using the same approximation, we find confinement for the exceptional gauge group G(2) and a first-order deconfinement transition, also in agreement with lattice findings.Comment: Invited talk at the Landau Memorial Conference "Advances in Theoretical Physics", June 22-26, 2008, Chernogolovka, to be published in the Proceeding

Towards all-dielectric metamaterials and nanophotonics

We review a new, rapidly developing field of all-dielectric nanophotonics which allows to control both magnetic and electric response of structured matter by engineering the Mie resonances in high-index dielectric nanoparticles. We discuss optical properties of such dielectric nanoparticles, methods of their fabrication, and also recent advances in all-dielectric metadevices including couple-resonator dielectric waveguides, nanoantennas, and metasurfaces

Quantum magnetism with multicomponent polar molecules in an optical lattice

We consider bosonic dipolar molecules in an optical lattice prepared in a mixture of different rotational states. The 1/r^3 interaction between molecules for this system is produced by exchanging a quantum of angular momentum between two molecules. We show that the Mott states of such systems have a large variety of non-trivial spin orderings including a state with ordering wave vector that can be changed by tilting the lattice. As the Mott insulating phase is melted, we also describe several exotic superfluid phases that will occur

Causal analysis of the interinfluence of workforce productivity and rail freight intensity in the regions of the Ural Federal District

Relevance. The development of the railway industry has a significant positive impact on socio-economic dynamics at both the state and regional levels, which has been confirmed by numerous domestic and foreign studies. However, the issue of mutual influence of such categories as regional labour productivity and rail freight intensity has been little studied. At the same time, the most important task today is to find effective incentives for the growth of regional labour productivity.Research Objective. This study aims to econometric analysis of the relationship between rail freight intensity and workforce productivity in the Ural Federal District (UFD).Data and Methods. The study uses official statistical data on Russian regions provided by the Federal State Statistics Service. The methods of Vector Error Correction Models (VECM) and pooled mean group estimates (PMG method) formed the methodological basis of the study.Results. The study has shown that there is a relationship between workforce productivity and rail freight intensity. At that point, in a short-term period growth of rail freight intensity leads to an increase in workforce productivity, which in a long-term period itself becomes an incentive to increase the shipped commodity mass and rail freight intensity.Conclusions. The findings can be of interest to public authorities at the national and regional levels, for heads of industrial structures and functional institutions, representatives of business and scientific communities interested in the development and modernization of transport infrastructure, being a basic condition for the increased intensity of cargo transportation in the region

Ranking of transport network development projects in the Sverdlovsk railroad area based on fuzzy logic

Relevance.  Due to the turbulence of economic processes in the period of sanctions pressure on the economy, decisions should be made, effective, first of all, from a national position.  For this purpose, it is necessary to justify them using multi-criteria and all available information, which at the initial stages is fundamentally incomplete, insufficiently reliable and sometimes weakly formalized. In such cases, it is advisable to use special methods to assess the decisions made in conditions of uncertainty, in particular methods of fuzzy logic and mathematics.Purpose of the study. The study is aimed at assessing the order of priority of transport rail support on the investigated most important in the federal and regional scale main lines by including the most significant technological and economic criteria, reflecting the nationwide priority.Data and Methods. To compare different methods of priority construction of the main lines of railway lines, we used the procedure of fuzzy multi-criteria analysis of the projects. The assumed priorities of transport rail support are based on four trunk line projects: the Middle Urals Latitudinal Railway on the N-Tagil - Perm section; the Troitsko-Pechorsk - Ivdel section; the Perm - Chernushka section; the Ust - Aha - Uray - Khanty-Mansiysk - Salym section.Results. The paper proves the possibility of applying the approach based on fuzzy logic to the analysis of economic processes in the period of shocks to the economy, caused, in particular, by the introduction of sanctions from unfriendly countries. The estimated priority of transport rail support on the four projects of the most important trunk lines is assessed.Conclusions. With the help of fuzzy logic methods, it is possible to find compromise options that satisfy the various interests of those affecting the decisions, regardless of the structural organization of the backbone industries, one of which is undoubtedly the transport industry

Acoustic Lateral Recoil Force and Stable Lift of Anisotropic Particles

Acoustic forces and torques are of immense importance for manipulation of particles, in particular in biomedical applications. While such forces and torques are well understood for small spherical particles with lowest-order monopole and dipole responses, the higher-order effects for larger anisotropic particles have not been properly investigated. Here we examine the acoustic force and torque on an anisotropic (ellipsoid) particle and reveal two novel phenomena. First, we describe the lateral recoil force, orthogonal to the direction of the incident wave and determined by the tilted orientation of the particle. Second, we find conditions for the stable acoustic lift, where the balanced torque and force produce a stable lateral drift of the tilted particle. We argue that these phenomena can bring about new functionalities in acoustic manipulation and sorting of anisotropic particles including biological objects such as blood cells.Comment: 11 pages, 7 figure

Paucity of chimeric gene-transposable element transcripts in the Drosophila melanogastergenome

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Recent analysis of the human and mouse genomes has shown that a substantial proportion of protein coding genes and cis-regulatory elements contain transposable element (TE) sequences, implicating TE domestication as a mechanism for the origin of genetic novelty. To understand the general role of TE domestication in eukaryotic genome evolution, it is important to assess the acquisition of functional TE sequences by host genomes in a variety of different species, and to understand in greater depth the population dynamics of these mutational events. Results Using an in silico screen for host genes that contain TE sequences, we identified a set of 63 mature "chimeric" transcripts supported by expressed sequence tag (EST) evidence in the Drosophila melanogaster genome. We found a paucity of chimeric TEs relative to expectations derived from non-chimeric TEs, indicating that the majority (~80%) of TEs that generate chimeric transcripts are deleterious and are not observed in the genome sequence. Using a pooled-PCR strategy to assay the presence of gene-TE chimeras in wild strains, we found that over half of the observed chimeric TE insertions are restricted to the sequenced strain, and ~15% are found at high frequencies in North American D. melanogaster populations. Estimated population frequencies of chimeric TEs did not differ significantly from non-chimeric TEs, suggesting that the distribution of fitness effects for the observed subset of chimeric TEs is indistinguishable from the general set of TEs in the genome sequence. Conclusion In contrast to mammalian genomes, we found that fewer than 1% of Drosophila genes produce mRNAs that include bona fide TE sequences. This observation can be explained by the results of our population genomic analysis, which indicates that most potential chimeric TEs in D. melanogaster are deleterious but that a small proportion may contribute to the evolution of novel gene sequences such as nested or intercalated gene structures. Our results highlight the need to establish the fixity of putative cases of TE domestication identified using genome sequences in order to demonstrate their functional importance, and reveal that the contribution of TE domestication to genome evolution may vary drastically among animal taxa.Published versio

Expert Group Formation for Task Performing: Competence-Based Method and Implementation

The problem of searching a group of experts to solve cross-domain problems remains an important problem in many applications. An automated expert search can make human resource management more efficient and reduce the number of problems. The paper presents a method of expert group formation for joint task performing. This method checks each available expert who can participate in task performing and sifts out the least effective of them. During this checking it forms several groups of experts and sorts them by their optimality based on their proficiency level, cost and influence of experts on each other. The method is implemented and approbated in a competence management system developed earlier