Analytical representation of elastic scattering cross sections of low energy electrons by atmospheric gases

Analytical representations of the elastic scattering cross sections of electrons with energies of 0.01-1 keV in atmospheric gases of N2, O2, O are given. These representations are suitable for the Monte Carlo method

Polaron transformations in the realistic model of the strongly correlated electron system

Electron-phonon coupling, diagonal in a real space formulation, leads to polaron paradigm of smoothly varying properties. However, fundamental changes, namely the singular behavior of polarons, occur if non-diagonal pairing is involved into consideration. The study of polaron transformations and related properties of matter is of particular interest for realistic models, since competition between diagonal and non-diagonal electron-phonon contributions in the presence of other strong interactions can result in unconventional behavior of the system. Here we consider the multiband pd-model of cuprate superconductors with electron-phonon interaction and analyze the features of the systems that are caused by the competition of diagonal and non-diagonal electron-phonon contributions in the limit of strong electron correlations. Using the polaronic version of the generalized tight-binding method, we describe the evolution of the band structure, Fermi surface, density of states at Fermi level, and phonon spectral function in the space of electron-phonon parameters ranging from weak to strong coupling strength of the adiabatic limit. On the phase diagram of polaron properties we reveal two quantum phase transitions and show how electron-phonon interaction gives rise to Fermi surface transformation (i) from hole pockets to Fermi arcs and (ii) from hole to electron type of conductivity. We also demonstrate the emergence of new states in the phonon spectral function of the polaron and discuss their origin.Comment: 14 pages, 7 figure

From underdoped to overdoped cuprates: two quantum phase transitions

Several experimental and theoretical studies indicate the existence of a critical point separating the underdoped and overdoped regions of the high-T_c cuprates' phase diagram. There are at least two distinct proposals on the critical concentration and its physical origin. First one is associated with the pseudogap formation for p<p*, with p~0.2. Another one relies on the Hall effect measurements and suggests that the critical point and the quantum phase transition (QPT) take place at optimal doping, p_{opt}~0.16. Here we have performed a precise density of states calculation and found that there are two QPTs and the corresponding critical concentrations associated with the change of the Fermi surface topology upon doping

The Problem of Law-Abiding Behavior among Minors in Educational Institutions: Domestic and Foreign Experience

At present, the problem of sustaining the law-abiding behavior of minors in educational institutions, identifying and eliminating the causes and conditions that contribute to the development of deviant behavior of students is becoming more and more topical. This paper presents the results of a monitoring study of the current state of the activities carried out by educational institutions to form the law-abiding behavior of minors in the territorial entities of the Russian Federation. It also presents the results of a theoretical study of the foreign experience of educational institutions in the framework of maintaining the law-abiding behavior of minors in the educational environment. The conclusions have been drawn that a system-activity approach should be the basis of an educational impact in educational institutions which will provide: the formation of students’ readiness for self-development; the design and construction of a social environment for the development of students based on moral principles, traditional Russian values, relevant scientific knowledge and skills, respect for the traditions of the multinational, multicultural and multiconfessional Russian society; active educational and cognitive activities of students; building educational and moral education activity, taking account of the individual age-related psychological and physiological characteristics of students and with a focus on educational results. The materials of the paper are part of a large-scale study within the framework of the "Conception for the development of a system for the prevention of neglect and juvenile delinquency for the period up to 2020", conducted by a team of scientists from 2017 to 2020, whose scientific interests lie in the study of the problem of deviant behavior of minors

Prognostic factors in patients with hematological malignancies and concomitant chronic hepatitis C

The study evaluated the impact of HCV infection on the prognosis in patients with hematological malignancies. A total of 96 patients with anti-HCV antibodies were enrolled, with the age of 37.8 (3.0–81.0) years old, 39.6% had non-Hodgkin’s lymphoma. Chronic hepatitis C (CHC) was diagnosed in 46.9% patients prior to malignancy development, in 38.5% patients simultaneously with malignancy, and in 14.6% patients during malignancy treatment. Clinical and biochemical signs of HCH were mild in most of the patients, minimal liver fibrosis (F0–1 by METAVIR system) was discovered in 47.3% patients, severe fibrosis or cirrhosis (F3–4) was diagnosed in 40% of participants. Only 20 (20.8%) of patients received antiviral therapy against HCV prior to enrollment. Regression analysis demonstrated that age 55 years old, late onset of antiviral therapy, and poor nutritional status were significant predictors of death from hematological malignancy. Survey conducted among physicians of hematological oncology hospitals in Saint-Petersburg revealed gaps in knowledge on presentation and risks of HCV infection, as well as on opportunities of modern antiviral therapy

Comparative characteristics of software navigation surgery "R2GATE" (MEGAGEN), "NOBELCLINICIAN" (NOBEL BIOCARE), «IMPLANT-GUIDE» (IMPLANT ASSISTANT) AND «MGUIDE» (MIS)

The article examines four programs for computer planning of dental implantation using surgical guides: "R2gate" (Megagen), "Nobel Clinic" (Nobel Biocare), «Implant-Guide» (Implant assistant), «Mguide» (MIS). The comparison has been carried out; features of each of four programs on the chosen criteria have been indicatedВ статье рассмотрены четыре программы для компьютерного планирования имплантации с использованием хирургического шаблона: «R2gate» (Megagen), «Nobel Clinician» (Nobel Biocare), «Implant-Guide» (Implant assistant), «Mguide» (MIS). Проведена сравнительная характеристика, выделены особенности каждой из четырёх программ по выбранным критериям

Lifshitz quantum phase transitions and Fermi surface transformation with hole doping in high-TcT_c superconductors

We study the doping evolution of the electronic structure in the normal phase of high-$T_c$ cuprates. Electronic structure and Fermi surface of cuprates with single CuO$_2$ layer in the unit cell like La$_{2-x}$Sr$_x$CuO$_4$ have been calculated by the LDA+GTB method in the regime of strong electron correlations (SEC) and compared to ARPES and quantum oscillations data. We have found two critical concentrations, $x_{c1}$ and $x_{c2}$, where the Fermi surface topology changes. Following I.M. Lifshitz ideas of the quantum phase transitions (QPT) of the 2.5-order we discuss the concentration dependence of the low temperature thermodynamics. The behavior of the electronic specific heat $\delta(C/T) \sim (x - x_c)^{1/2}$ is similar to the Loram and Cooper experimental data in the vicinity of $x_{c1} \approx 0.15$.Comment: 8 pages, 4 figure

The effectiveness of pulsed magnitophoresis in the complex treatment of chronic generalized periodontitis with the use of compositions based on silicon-organic glycerohydrogel

The work outlines the main findings of the study the effectiveness of applying a new method of the treatment of chronic generalized periodontitis by means of pulsed magnitophoresis, developed drug composition based on silicone-organic glycerohydrogelВ работе изложены основные результаты исследования эффективности применения нового метода лечения хронического генерализованного пародонтита посредством проведения импульсного магнитофореза разработанной лекарственной композиции на основе кремнийорганического глицерогидрогеля