Convergent series for lattice models with polynomial interactions

The standard perturbative weak-coupling expansions in lattice models are asymptotic. The reason for this is hidden in the incorrect interchange of the summation and integration. However, substituting the Gaussian initial approximation of the perturbative expansions by a certain interacting model or regularizing original lattice integrals, one can construct desired convergent series. In this paper we develop methods, which are based on the joint and separate utilization of the regularization and new initial approximation. We prove, that the convergent series exist and can be expressed as the re-summed standard perturbation theory for any model on the finite lattice with the polynomial interaction of even degree. We discuss properties of such series and make them applicable to practical computations. The workability of the methods is demonstrated on the example of the lattice $\phi^4$-model. We calculate the operator $\langle\phi_n^2\rangle$ using the convergent series, the comparison of the results with the Borel re-summation and Monte Carlo simulations shows a good agreement between all these methods.Comment: 25 pages, 14 figure

Nonlinear states and dynamics in a synthetic frequency dimension

Recent advances in the study of synthetic dimensions revealed a possibility to employ the frequency space as an additional degree of freedom which allows for investigating and exploiting higher-dimensional phenomena in a priori low-dimensional systems. However, the influence of nonlinear effects on the synthetic frequency dimensions was studied only under significant restrictions. In the present paper, we develop a generalized mean-field model for the optical field envelope inside a single driven-dissipative resonator with quadratic and cubic nonlinearities, whose frequencies are coupled via an electro-optical resonant temporal modulation. The leading order equation takes the form of driven Gross-Pitaevskii equation with a cosine potential. We numerically investigate the nonlinear dynamics in such microring resonator with a synthetic frequency dimension in the regime where parametric frequency conversion occurs. In the case of anomalous dispersion, we find that the presence of electro-optical mode coupling confines and stabilizes the chaotic modulation instability region. This leads to the appearance of a novel type of stable coherent structures which emerge in the synthetic space with restored translational symmetry, in a region of parameters where conventionally only chaotic modulation instability states exist. This structure appears in the center of the synthetic band and, therefore, is referred to as Band Soliton. Finally, we extend our results to the case of multiple modulation frequencies with controllable relative phases creating synthetic lattices with nontrivial geometry. We show that an asymmetric synthetic band leads to the coexistence of chaotic and coherent states of the electromagnetic field inside the cavity i.e. dynamics that can be interpreted as chimera-like states. Recently developed $\chi^{(2)}$ microresonators can open the way to experimentally explore our findings.Comment: 12 pages, 5 figures; figure 4 and typos correcte

Получение ультрадисперсных материалов системы Cu-Si в электроразрядной плазме

В работе показана возможность получения ультрадисперсных материалов системы Cu-Siв электроразрядной плазме дугового разряда. Получены кубические модификации ультрадисперсноймеди, кремния, а также фаза силицида меди ηʺ-Cu3Si. Установлено, что в зависимости от места сборапорошкового продукта в экспериментальной установке (в реакторе, на электродах) соотношение перечисленных выше компонентов продукта различно

Radiative corrections to the lightest KK states in the T^2/(Z_2\times Z_2') orbifold

We study radiative corrections localized in the fixed points of the orbifold for the field theory in six dimensions with two dimensions compactified on the $T_2/(Z_2\times Z_2')$ orbifold in a specific realistic model for low energy physics that solves the proton decay and neutrino mass problem. We calculate corrections to the masses of the lightest stable KK modes, which could be the candidates for the dark matter.Comment: 14 pages, 2 figure

Experimental facility control system for optical studies in the frame of problem solving of brain hematoma diagnostics

The article describes a system to control a unit moving to find the dependence of the photodetectors signals from the distance to the hematoma. It considers existing devices that operate in accordance with the principle of near infrared spectroscopy and reveals their limitations the illuminations of which are our key objective. The limitations of the designed unit are described and possible ways of upgrading the system are outlined

Fully-automated and ultra-fast cell-type identification using specific marker combinations from single-cell transcriptomic data

Identification of cell populations often relies on manual annotation of cell clusters using established marker genes. However, the selection of marker genes is a time-consuming process that may lead to sub-optimal annotations as the markers must be informative of both the individual cell clusters and various cell types present in the sample. Here, we developed a computational platform, ScType, which enables a fully-automated and ultra-fast cell-type identification based solely on a given scRNA-seq data, along with a comprehensive cell marker database as background information. Using six scRNA-seq datasets from various human and mouse tissues, we show how ScType provides unbiased and accurate cell type annotations by guaranteeing the specificity of positive and negative marker genes across cell clusters and cell types. We also demonstrate how ScType distinguishes between healthy and malignant cell populations, based on single-cell calling of single-nucleotide variants, making it a versatile tool for anticancer applications. The widely applicable method is deployed both as an interactive web-tool (https://sctype.app ), and as an open-source R-package.Peer reviewe

Spin-Orbit Dirac Fermions in 2D Systems

We propose a novel model for including spin-orbit interactions in buckled two dimensional systems. Our results show that in such systems, intrinsic spin-orbit coupling leads to a formation of Dirac cones, similar to Rashba model. We explore the microscopic origins of this behaviour and confirm our results using DFT calculations

Ideology and philosophy of the successful regional development in contemporary Russia: the Belgorod case

The article considers economic successes of the Belgorod region as significantly determined by the governor Yevgeny Savchenko' agrarian policies, which compensate for the region's small size and modest human capital. In 2017, the authors published an article describing economic policies and social programs of regional authorities; now the authors focus on the leadership by Yevgeny Savchenko, and his rather paradoxical personal and management views. First, according to Max Weber's typology of authority, Savchenko is a charismatic leader with strong personality traits and careful political behavior, who benefits from the traditional Slavophile populism and institutional design of the gubernatorial powers that has allowed governors to become more powerful compared to other regional actors during 2002-2012. Second, the Belgorod governor's project has quite traditional Russian roots in the spirit of A.V. Chayanov's novel "My brother Alexey's journey to the land of peasant utopia", which allowed the Belgorod modernization project to successfully cope with unpredictable challenges from the Russian oligarchy and global economy, and to use competitive standards of consumer society as the grounds for conservative modernization and solidary society development. The Belgorod governor implements his own model of new economy consisting of the extensive development of solidarity and cooperation; ideals of healthy lifestyle; and freedom in choosing ways to work and to rest (regional authorities support corporate, family and individual strategies of life). Third, Savchenko has publicly articulated his personal political-economic theory reflecting a conglomerate of conservative, socialist and populist ideas, and combining anti-liberalism and statist philosophy as the basis for the revival of the Russian state, which the governor sees as an engine of social progress

SynergyFinder 2.0 : visual analytics of multi-drug combination synergies

SynergyFinder (https://synergyfinder.fimm.fi) is a stand-alone web-application for interactive analysis and visualization of drug combination screening data. Since its first release in 2017, SynergyFinder has become a widely used web-tool both for the discovery of novel synergistic drug combinations in pre-clinical model systems (e.g. cell lines or primary patient-derived cells), and for better understanding of mechanisms of combination treatment efficacy or resistance. Here, we describe the latest version of SynergyFinder (release 2.0), which has extensively been upgraded through the addition of novel features supporting especially higher-order combination data analytics and exploratory visualization of multi-drug synergy patterns, along with automated outlier detection procedure, extended curve-fitting functionality and statistical analysis of replicate measurements. A number of additional improvements were also implemented based on the user requests, including new visualization and export options, updated user interface, as well as enhanced stability and performance of the web-tool. With these improvements, SynergyFinder 2.0 is expected to greatly extend its potential applications in various areas of multi-drug combinatorial screening and precision medicine.Peer reviewe