Topological phases induced by charge fluctuations in Majorana wires

One of the problems concerning topological phases in solid-state systems which still remains urgent is an issue of many-body effects. In this study we address it within perturbative theory framework by considering topological phase transitions related to charge correlations in the extended Kitaev chain model that belongs to the BDI symmetry class. Obtained corrections to a zero-frequency quasiparticle Green's function allow to separate the mean-field and fluctuation contributions to a total winding number. As a result, the phase transitions caused solely by the latter are unveiled. We thoroughly analyze the mechanism of such transitions in terms of fluctuation-induced nodal points and spectrum renormalization. Additionally, features of other quasiparticle properties such as effective mass and damping are discussed in the context of topological phase transitions.Comment: 20 pages, 15 figure

PHYSICAL ASPECTS OF VACUUM-ARC COATING DEPOSITION

The brief analytical review of literary data concerning the processes which are a physical basis of vacuum-arc coating deposition technology is presented. The phenomena responsible for formation of films by condensation of substance from plasma of arc discharge in vacuum or in a gaseous ambience of low pressure are described.. Interaction of metal plasma with a gas target, a substrate and other surfaces of working chamber, the processes of nucleation and condensate growth, influence of energetic parameters of a deposition process (kinetic and potential energy of metal ions, activation degree and sort of the gas ) on properties of condensates and near-surface layers of the substrate are described

Feasibility of study magnetic proximity effects in bilayer "superconductor/ferromagnet" using waveguide-enhanced Polarized Neutron Reflectometry

A resonant enhancement of the neutron standing waves is proposed to use in order to increase the magnetic neutron scattering from a "superconductor/ferromagnet"(S/F) bilayer. The model calculations show that usage of this effect allows to increase the magnetic scattering intensity by factor of hundreds. Aspects related to the growth procedure (order of deposition, roughness of the layers etc) as well as experimental conditions (resolution, polarization of the neutron beam, background etc) are also discussed. Collected experimental data for the S/F heterostructure Cu(32nm)/V(40nm)/Fe(1nm)/MgO confirmed the presence of a resonant 60-fold amplification of the magnetic scattering.Comment: The manuscript of the article submitted to Crysstalography Reports. 23 pages, 5 figure

Recovering rearranged cancer chromosomes from karyotype graphs

BACKGROUND: Many cancer genomes are extensively rearranged with highly aberrant chromosomal karyotypes. Structural and copy number variations in cancer genomes can be determined via abnormal mapping of sequenced reads to the reference genome. Recently it became possible to reconcile both of these types of large-scale variations into a karyotype graph representation of the rearranged cancer genomes. Such a representation, however, does not directly describe the linear and/or circular structure of the underlying rearranged cancer chromosomes, thus limiting possible analysis of cancer genomes somatic evolutionary process as well as functional genomic changes brought by the large-scale genome rearrangements. RESULTS: Here we address the aforementioned limitation by introducing a novel methodological framework for recovering rearranged cancer chromosomes from karyotype graphs. For a cancer karyotype graph we formulate an Eulerian Decomposition Problem (EDP) of finding a collection of linear and/or circular rearranged cancer chromosomes that are determined by the graph. We derive and prove computational complexities for several variations of the EDP. We then demonstrate that Eulerian decomposition of the cancer karyotype graphs is not always unique and present the Consistent Contig Covering Problem (CCCP) of recovering unambiguous cancer contigs from the cancer karyotype graph, and describe a novel algorithm CCR capable of solving CCCP in polynomial time. We apply CCR on a prostate cancer dataset and demonstrate that it is capable of consistently recovering large cancer contigs even when underlying cancer genomes are highly rearranged. CONCLUSIONS: CCR can recover rearranged cancer contigs from karyotype graphs thereby addressing existing limitation in inferring chromosomal structures of rearranged cancer genomes and advancing our understanding of both patient/cancer-specific as well as the overall genetic instability in cancer

A hydrodynamic model for asymmetric explosions of rapidly rotating collapsing supernovae with a toroidal atmosphere

We numerically solved the two-dimensional axisymmetric hydrodynamic problem of the explosion of a low-mass neutron star in a circular orbit. In the initial conditions, we assumed a nonuniform density distribution in the space surrounding the collapsed iron core in the form of a stationary toroidal atmosphere that was previously predicted analytically and computed numerically. The configuration of the exploded neutron star itself was modeled by a torus with a circular cross section whose central line almost coincided with its circular orbit. Using an equation of state for the stellar matter and the toroidal atmosphere in which the nuclear statistical equilibrium conditions were satisfied, we performed a series of numerical calculations that showed the propagation of a strong divergent shock wave with a total energy of 0.2x10^51 erg at initial explosion energy release of 1.0x10^51 erg. In our calculations, we rigorously took into account the gravitational interaction, including the attraction from a higher-mass (1.9M_solar) neutron star located at the coordinate origin, in accordance with the rotational explosion mechanism for collapsing supernovae.W e compared in detail our results with previous similar results of asymmetric supernova explosion simulations and concluded that we found a lower limit for the total explosion energy.Comment: 13 pages, 5 figures, 2 table

Importance of Resultant Action of the Mining Machine Actuator for Stresses in Impact Zone of a Separate Cutter

Two stress levels are considered in the general pattern of stress-strain state of the rock destroyed by the mining machine. The authors also ground the necessity of considering the interaction of all cutters of the actuating device when calculating the process of cutting with a separate cutter

Remote clinical quality management of endovascular care

Aim. To assess the effectiveness of remote clinical quality management of endovascular care.Methods. The system of clinical quality management of medical care in myocardial infarction (MI) including the quality of remote control of endovascular care was developed and introduced into the health care system of the Moscow Region as a part of the comprehensive study in 2008–2020. The number of people under the study was 8375. The ground for assessing the effectiveness of remote clinical management in 2019–2020 was the health care system of megapolis. Based on the analysis of 2966 endovascular procedures protocols, the treatment tactics effectiveness of intraoperative decisions was studied after an emergency coronary angiography (ECA) had been performed by interventional cardiologists. The system of remote clinical quality management of endovascular care included a complex of audiovisual communications, computer system processes, mentoring and the algorithm for making an intraoperative decision. The effectiveness of remote clinical quality management of endovascular care was investigated on the number of percutaneous coronary interventions (PCI) in MI, mortality of patients with MI in the Regional vascular center in 2019–2020. The T-criteria was used to assess the reliability. The material statistical processing was carried out in the Statistica 6.0 package calculating adequate statistical indicators and their reliability at p≤0.005.Results. Ratio PCI/ECA in 2019, January-March 2020 counted up to 48.95%. In AprilDecember 2020 it increased up to 71.6% (p<0.001). The frequency of performing PCI increased by 1.46 times (p<0.001). Hospital mortality from MI decreased during the following period 2019, April-December 2020 from 9.7% to 8.2% (p = 0.005).Conclusion. Remote clinical management based on telemedicine and mentoring process technologies contributes to improving the quality of endovascular care in MI.Aim. To assess the effectiveness of remote clinical quality management of endovascular care.Methods. The system of clinical quality management of medical care in myocardial infarction (MI) including the quality of remote control of endovascular care was developed and introduced into the health care system of the Moscow Region as a part of the comprehensive study in 2008–2020. The number of people under the study was 8375. The ground for assessing the effectiveness of remote clinical management in 2019–2020 was the health care system of megapolis. Based on the analysis of 2966 endovascular procedures protocols, the treatment tactics effectiveness of intraoperative decisions was studied after an emergency coronary angiography (ECA) had been performed by interventional cardiologists. The system of remote clinical quality management of endovascular care included a complex of audiovisual communications, computer system processes, mentoring and the algorithm for making an intraoperative decision. The effectiveness of remote clinical quality management of endovascular care was investigated on the number of percutaneous coronary interventions (PCI) in MI, mortality of patients with MI in the Regional vascular center in 2019–2020. The T-criteria was used to assess the reliability. The material statistical processing was carried out in the Statistica 6.0 package calculating adequate statistical indicators and their reliability at p≤0.005.Results. Ratio PCI/ECA in 2019, January-March 2020 counted up to 48.95%. In AprilDecember 2020 it increased up to 71.6% (p<0.001). The frequency of performing PCI increased by 1.46 times (p<0.001). Hospital mortality from MI decreased during the following period 2019, April-December 2020 from 9.7% to 8.2% (p = 0.005).Conclusion. Remote clinical management based on telemedicine and mentoring process technologies contributes to improving the quality of endovascular care in MI

A Rotating Collapsar and Possible Interpretation of the LSD Neutrino Signal from SN 1987A

We consider an improved rotational mechanism of the explosion of a collapsing supernova. We show that this mechanism leads to two-stage collapse with a phase difference of \sim 5 h. Based on this model, we attempt a new interpretation of the events in underground neutrino detectors on February 23, 1987, related to the supernova SN 1987A.Comment: 18 pages, 3 figures, 9 table

Features of the complement system in primary open-angle glaucoma and dry eye syndrome in the elderly

Primary open-angle glaucoma combined with dry eye syndrome is the leading cause of irreversible blindness. Complement system remains nearly unexplored in this disorder. The aim of our study was to evaluate the parameters of complement system in primary open-angle glaucoma and dry eye syndrome among elderly persons. The study was conducted at the S. Fedorov Center of Eye Microsurgery (Tambov Branch), and enrolled 62 patients aged 60 to 74 years with primary open-angle glaucoma combined with dry eye syndrome, and 33 patients free of this pathology. The blood complement system was studied by hemolytic method and enzyme immunoassay, and the C1 inhibitor was studied by chromogenic method. To assess possible contribution of the complement system components to the mentioned eye disorder, appropriate odds ratios were calculated, according to the generally accepted method. The study of blood complement system in elderly patients with combined primary open-angle glaucoma and dry eye syndrome have shown, first of all, high C3a level (up to 106.2±3.9 ng/ml), increased contents of C5a (4.5±0.2 ng/ml), and factor H (215.9±5.2 mcg/ml), along with decreased C1 inhibitor (to 168.4±6.1 mcg/ml). In the age-matched control group, the contents of appropriate plasma complement factors were, respectively, 45.2±4.0 ng/ml; 3.1±0.2 ng/ml; 141.5±4.3 mcg/ml; 237.9±5.8 mcg/ml, showing significant difference for all these parameters. An important pathogenetic role of C3a component, C5a component, factor H, and the C1 inhibitor in development of combined primary openangle glaucoma with dry eye syndrome was confirmed by the values of odds ratio (OR) with maximum value for the C3a component (OR 4.035, CI 3.640-4.283, p < 0.0001), which indicates increased risk of developing the mentioned ophthalmopathology in old age. High odd ratios were also characteristic of C5a blood components (2.946; CI 2.618-3.547), C3 (2.821; CI 2.453-3.264), factor H (2.765; CI 2.431-3.148). Less significant changes were revealed for other complement components thus suggesting only marginal association with development of primary open-angle glaucoma with dry eye syndrome in old age This indicates that the development of primary open-angle glaucoma with dry eye syndrome is associated with activation of these factors of the complement system. The revealed features of the complement system will enable us for more effective diagnostics of these combined eye disorders

Thermalization of a nonequilibrium electron-positron-photon plasma

Starting from a nonequilibrium configuration we analyse the essential role of the direct and the inverse binary and triple interactions in reaching an asymptotic thermal equilibrium in a homogeneous isotropic electron-positron-photon plasma. We focus on energies in the range 0.1--10 MeV. We numerically integrate the integro-partial differential relativistic Boltzmann equation with the exact QED collisional integrals taking into account all binary and triple interactions in the plasma. We show that first, when detailed balance is reached for all binary interactions on a timescale $t_{k}\lesssim10^{-14}$sec, photons and electron-positron pairs establish kinetic equilibrium. Successively, when triple interactions fulfill the detailed balance on a timescale $t_{eq}\lesssim10^{-12}$sec, the plasma reaches thermal equilibrium. It is shown that neglecting the inverse triple interactions prevents reaching thermal equilibrium. Our results obtained in the theoretical physics domain also find application in astrophysics and cosmology.Comment: 4 pages, 3 figures, Phys. Rev. Lett., to appea