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

IRI-2012 MODEL ADAPTABILITY ESTIMATION FOR AUTOMATED PROCESSING OF VERTICAL SOUNDING IONOGRAMS

The paper deals with possibility of IRI-2012 global empirical model applying to the vertical sounding of the ionosphere semiautomatic data processing. Main ionosphere characteristics from vertical sounding data at IZMIRAN Voeikovo station in February 2013 were compared with IRI-2012 model calculation results. 2688 model values and 1866 real values of f0F2, f0E, hmF2, hmE were processed. E and F2 layers critical frequency (f0E, f0F2) and the maximum altitudes (hmF2, hmE) were determined from the ionograms. Vertical profiles of the electron concentration were restored with IRI-2012 model by measured frequency and height. The model calculation was also made without the inclusion of the real vertical sounding data. Monthly averages and standard deviations (σ) for the parameters f0F2, f0E, hmF2, hmE for each hour of the day were calculated according to the vertical sounding and model values. Model applicability conditions for automated processing of ionograms for subauroral ionosphere were determined. Initial IRI-2012 model can be applied in the sub-auroral ionograms processing at daytime with undisturbed conditions in the absence of sporadic ionization. In this case model calculations can be adjusted by the near-time vertical sounding data. IRI-2012 model values for f0E (in daytime) and hmF2 can be applied to reduce computational costs in the systems of automatic parameters search and preliminary determination of the searching area range for the main parameters. IRI-2012 model can be used for a more accurate approximation of the real data series in the absence of the real values. In view of sporadic ionization, ionosphere models of the high latitudes must be applied with corpuscular ions formation unit

О применении технологий параллельного программирования для задач матричной алгебры в приложении к спектральному методу анализа, синтеза и идентификации систем управления

The article describes the matrix algebra libraries based on the modern technologies of parallel programming for the Spectrum software, which can use a spectral method (in the spectral form of mathematical description) to analyse, synthesise and identify deterministic and stochastic dynamical systems. The developed matrix algebra libraries use the following technologies for the GPUs: OmniThreadLibrary, OpenMP, Intel Threading Building Blocks, Intel Cilk Plus for CPUs nVidia CUDA, OpenCL, and Microsoft Accelerated Massive Parallelism.The developed libraries support matrices with real elements (single and double precision). The matrix dimensions are limited by 32-bit or 64-bit memory model and computer configuration. These libraries are general-purpose and can be used not only for the Spectrum software. They can also find application in the other projects where there is a need to perform operations with large matrices.The article provides a comparative analysis of the libraries developed for various matrix operations (addition, subtraction, scalar multiplication, multiplication, powers of matrices, tensor multiplication, transpose, inverse matrix, finding a solution of the system of linear equations) through the numerical experiments using different CPU and GPU. The article contains sample programs and performance test results for matrix multiplication, which requires most of all computational resources in regard to the other operations.В статье описываются библиотеки матричной алгебры, разработанные с применением современных технологий параллельного программирования для расчетной системы Spectrum. Расчетная система Spectrum может применяться в разных задачах анализа, синтеза и идентификации детерминированных и стохастических динамических систем спектральным методом (в спектральной форме математического описания). Проведен сравнительный анализ разработанных библиотек на основе вычислительных экспериментов с применением различного аппаратного обеспечения (центральных процессоров и графических процессоров видеоадаптеров). DOI: 10.7463/mathm.0116.084107

Professional Doctorates: International Experience and Russian Context

The diversification of forms and types of doctoral programs is currently a global trend. Universities across the globe offer programs that differ in the modes of training, characteristics of the target audience, and possible labor markets after graduation. In Russia, doctoral education exists in a unified format, focusing primarily on the academic labor market. Recently, there have been discussions about the need to expand the range of programs and the types of academic degrees in Russia. In this article, we present the analysis of professional doctoral programs: in response to what challenges and needs they appeared, how they are implemented, in what forms they exist. In addition, we consider the Russian experience of implementing professional doctoral programs; analyze the existing opportunities and barriers for their development. Based on the analysis, we came to a conclusion about the relevance of the professional doctoral programs’ development in Russia, the expediency of simplifying the conditions for their implementation and legitimizing special requirements for the design of dissertations with an applied orientation

Modern microwave methods in solid state inorganic materials chemistry: from fundamentals to manufacturing

No abstract available

The BM@N spectrometer at the NICA accelerator complex

BM@N (Baryonic Matter at Nuclotron) is the first experiment operating and taking data at the Nuclotron/NICA ion-accelerating complex.The aim of the BM@N experiment is to study interactions of relativistic heavy-ion beams with fixed targets. We present a technical description of the BM@N spectrometer including all its subsystems.Comment: 34 pages, 47 figures, 6 table

Выбор оптимального объема хирургического лечения при аноректальной меланоме: ретроспективный анализ реестра Российского общества специалистов по колоректальному раку

Background. Anorectal melanoma is a rare malignancy without established standard treatment.Aim. To analyse the Russian Colorectal Cancer Society melanoma registry and to assess optimal surgery with regard to the extent of the disease.Materials and methods. A retrospective analysis of the Russian Colorectal Cancer Society registry was carried out during 2000–2020. Patients with cutaneous melanoma colonic metastases as well as patients with less than 6 months follow-up were excluded. Basic patient group characteristics, overall and disease-free survival (were analyzed depending on disease stage (by A. Stefanou) and surgery type.Results. 16 patients had stage I–IIA, 24 – stage IIB, 29 patients – stage III and 24 patients – stage IV disease. Wide local excision was performed in 15 (93.8 %) patients with stage I–IIA, 15 (62.5 %) patients with stage IIB, 2 (6.9 %) patients with stage III, and 8 (33.3 %) patients with stage IV disease. Abdomino-perineal excision (APE) was performed in 0 patients with stage I–IIA, 7 (29.2 %) patients with stage IIB, 22 (75.9 %) patients with stage III, and 7 (29.2 %) patients with stage IV disease. 2-year overall survival was 74.5 % in stage I–IIA, 49.4 % in stage IIB, 64.3 % in stage III, and 10.4 % in stage IV disease; 2-year disease-free survival was 67 %, 23,4 %, 34,1 % in stage I–IIA, IIB, III disease accordingly. Median overall survival was 17.8 months, 38.3 months and 27.9 months for non-surgical treatment, wide local excision and APR in non-metastatic patients accordingly. Median disease-free survival was 6.0 months, 14.1 months and 12.0 months for non-surgical treatment, wide local excision and APR in non-metastatic patients accordingly.Conclusions. APR should be considered in patients with stage IIB and stage III (by A. Stefanou) anorectal melanoma. Wide local excision is the preferred treatment in other patients.Введение. Аноректальная меланома – редкое злокачественное новообразование, для которого отсутствуют общепринятые стандарты лечения.Цель исследования – анализ данных реестра редких заболеваний Российского общества специалистов по колоректальному раку по аноректальной меланоме и оценка оптимальной тактики лечения при различной степени распространенности заболевания.Материалы и методы. Проведен ретроспективный анализ реестра аноректальных меланом Российского общества специалистов по колоректальному раку за 2000–2020 гг. Из анализа исключали пациентов с метастазами меланомы кожи в толстую кишку, пациентов, прослеженных <6 мес. Анализировали основные клинические характеристики, характер метастазирования при различных стадиях, общую и безрецидивную выживаемость в зависимости от стадии по A. Stefanou и вида хирургического лечения.Результаты. В исследуемой группе было 16 пациентов с I–IIA стадией, 24 пациента с IIB стадией, 29 пациентов с III стадией и 24 пациента с IV стадией. Трансанальное иссечение было выполнено 15 (93,8 %) пациентам с I–IIA стадией, 15 (62,5 %) пациентам с IIB стадией, 2 (6,9 %) пациентам с III стадией и 8 (33,3 %) пациентам с IV стадией. Брюшно-промежностная экстирпация (БПЭ) прямой кишки была выполнена 7 (29,2 %) пациентам с IIB стадией, 22 (75,9 %) пациентам с III стадией, 7 (29,2 %) пациентам с IV стадией и не была выполнена ни одному из пациентов с I–IIA стадией. Двухлетняя общая выживаемость составила 74,5; 49,4; 64,3 и 10,4 % при I–IIA, IIB, III и IV стадии соответственно, 2-летняя БРВ – 67,0; 23,4 и 34,1 % при I–IIA, IIB и III стадии соответственно. Медиана общей выживаемости при неметастатических случаях составила 17,8; 38,3 и 27,9 мес для нехирургического лечения, трансанального иссечения и БПЭ прямой кишки соответственно, медиана безрецидивной выживаемости – 6,0; 14,1 и 12,0 мес.Выводы. Выполнение БПЭ прямой кишки следует рассматривать у пациентов с IIB и III стадиями аноректальной меланомы по A. Stefanou. У остальных пациентов при технической возможности следует выполнять трансанальное иссечение