Nonlinear axisymmetric liquid currents in spherical annuli

A numerical analysis of non-linear axisymmetric viscous flows in spherical annuli of different gap sizes is presented. Only inner sphere was supposed to rotate at a constant angular velocity. The streamlines, lines of constant angular velocity, kinetic energy spectra, and spectra of velocity components are obtained. A total kinetic energy and torque needed to rotate the inner sphere are calculated as functions of Re for different gap sizes. In small-gap annulus nonuniqueness of steady solutions of Navier-Stokes equations is established and regions of different flow regime existences are found. Numerical solutions in a wide-gap annulus and experimental results are used in conclusions about flow stability in the considered range of Re. The comparison of experimental and numerical results shows close qualitative and quantitative agreement

Problemas de gestión empresarial en la actual situación de crisis

The paper examines the problems faced by enterprises in the real sector of the economy. These problems are not new; they have been discussed in the scientific community for a decade, but in today's realities, when the entire world economy lives in a pandemic, these problems have become aggravated and require a serious, balanced approach to their solution. All economic crises are primarily reflected in investment activity. That is why it is necessary to highlight economic security to ensure the effectiveness of budget investments. In this area, the bulk of violations and sometimes crimes are observed in the financial and investment area of relations of all participants in business processes in the economy. In general methodological terms, the article substantiates and reveals a proposal for organizing a system of indicative analysis and regulation of production volumes and production and economic activities of enterprises and organizations of the real sector of the economy as an organizational tool for resolving crisis situations in the economy. Both external and internal factors are touched upon, which caused the current unsatisfactory state of the Russian economy. In a concrete plan, the author's proposals on the directions and ways of overcoming the current crisis phenomena in the Russian economy are presented.El documento examina los problemas que enfrentan las empresas en el sector real de la economía. Estos problemas no son nuevos; se han debatido en la comunidad científica durante una década, pero en la realidad actual, cuando toda la economía mundial vive en una pandemia, estos problemas se han agravado y requieren un enfoque serio y equilibrado para su solución. Todas las crisis económicas se reflejan principalmente en la actividad inversora. Por eso es necesario resaltar la seguridad económica en el campo de asegurar la efectividad de las inversiones presupuestarias. Es en esta área donde se observan la mayor parte de las violaciones y, en ocasiones, los delitos en el área financiera y de inversión de las relaciones de todos los participantes en los procesos comerciales de la economía. En términos metodológicos generales, el artículo fundamenta y revela una propuesta de organización de un sistema de análisis indicativo y regulación de los volúmenes de producción y actividades productivas y económicas de las empresas y organizaciones del sector real de la economía, como herramienta organizativa para resolver situaciones de crisis en la economía. Se abordan los factores, tanto externos como internos, que causaron el actual estado insatisfactorio de la economía rusa. En un plan concreto, se presentan las propuestas del autor sobre las direcciones y formas de superar los fenómenos de crisis actuales en la economía rusa

Problemas de gestión empresarial en la actual situación de crisis

El documento examina los problemas que enfrentan las empresas en el sector real de la economía. Estos problemas no son nuevos; se han debatido en la comunidad científica durante una década,pero en la realidad actual, cuando toda la economía mundial vive en una pandemia, estos problemas se han agravado y requieren un enfoque serio y equilibrado para su solución. Todas las crisis económicas se reflejan principalmente en la actividad inversora. Por eso es necesario resaltar la seguridad económica en el campo de asegurar la efectividad de las inversiones presupuestarias. Es en esta área donde se observan la mayor parte de las violaciones y, en ocasiones, los delitos en el área financiera y de inversión de las relaciones de todos los participantes en los procesos comerciales de la economía. En términos metodológicos generales, el artículo fundamenta y revela una propuesta de organización de un sistema de análisis indicativo y regulación de los volúmenes de producción y actividades productivas y económicas de las empresas y organizaciones del sector real de la economía, como herramienta organizativa para resolver situaciones de crisis en la economía. Se abordan los factores, tanto externos como internos, que causaron el actual estado insatisfactorio de la economía rusa. En un plan concreto, se presentan las propuestas del autor sobre las direcciones y formas de superar los fenómenos de crisis actuales en la economía rus

Wavelets: mathematics and applications

The notion of wavelets is defined. It is briefly described {\it what} are wavelets, {\it how} to use them, {\it when} we do need them, {\it why} they are preferred and {\it where} they have been applied. Then one proceeds to the multiresolution analysis and fast wavelet transform as a standard procedure for dealing with discrete wavelets. It is shown which specific features of signals (functions) can be revealed by this analysis, but can not be found by other methods (e.g., by the Fourier expansion). Finally, some examples of practical application are given (in particular, to analysis of multiparticle production}. Rigorous proofs of mathematical statements are omitted, and the reader is referred to the corresponding literature.Comment: 16 pages, 5 figures, Latex, Phys. Atom. Nuc

Two-dimensional discrete wavelet analysis of multiparticle event topology in heavy ion collisions

The event-by-event analysis of multiparticle production in high energy hadron and nuclei collisions can be performed using the discrete wavelet transformation. The ring-like and jet-like structures in two-dimensional angular histograms are well extracted by wavelet analysis. For the first time the method is applied to the jet-like events with background simulated by event generators, which are developed to describe nucleus-nucleus collisions at LHC energies. The jet positions are located quite well by the discrete wavelet transformation of angular particle distribution even in presence of strong background.Comment: 6 pages, 6 figure

Current views on the role of fatty acids in the diagnosis of cardiovascular diseases (review)

An additional informative tool in the diagnosis of cardiovascular diseases in the early stages can be the analysis of changes in the fatty acid profile, which can be considered as a marker of various pathological conditions. The study of the effects of fatty acids and the mechanisms of changes in the fatty acid profile in connection with cardiovascular diseases remains relevant. We have analyzed modern data from foreign and domestic literature on issues related to the importance of fatty acids as possible markers in the diagnosis of cardiovascular diseases. Basic information about the structure of fatty acids, their functions in the human body, the relationship between the level of free fatty acids and indicators of the development of pathological processes of the cardiovascular system is presented. The factors influencing the dynamics of fatty acid concentrations both in normal conditions and during the development of pathological processes are reflected. The processes of biochemical modification of the fatty acid composition of the lipid matrix of the cell membrane are considered. The expediency of using fatty acids, together with some protein markers in the diagnosis of diseases of the cardiovascular system, has been shown. The collection and analysis of the accumulated information on the role of fatty acids helps to optimize the use of laboratory markers to determine the stages of pathogenesis of circulatory organ damage, to develop a system for evaluating the effectiveness of therapy for cardiovascular diseases, and to create a set of laboratory and instrumental tests for monitoring the condition of patients

Imaging and modeling the ionospheric airglow response over Hawaii to the tsunami generated by the Tohoku earthquake of 11 March 2011

Although only centimeters in amplitude over the open ocean, tsunamis can generate appreciable wave amplitudes in the upper atmosphere, including the naturally occurring chemiluminescent airglow layers, due to the exponential decrease in density with altitude. Here, we present the first observation of the airglow tsunami signature, resulting from the 11 March 2011 Tohoku earthquake off the eastern coast of Japan. These images are taken using a wide-angle camera system located at the top of the Haleakala Volcano on Maui, Hawaii. They are correlated with GPS measurements of the total electron content from Hawaii GPS stations and the Jason-1 satellite. We find waves propagating in the airglow layer from the direction of the earthquake epicenter with a velocity that matches that of the ocean tsunami. The first ionospheric signature precedes the modeled ocean tsunami generated by the main shock by approximately one hour. These results demonstrate the utility of monitoring the Earth's airglow layers for tsunami detection and early warning

Echohysterosalpingography: pros and cons. A systematic review

Background. Infertility is becoming ever more pressing a problem by year in Russia and worldwide. Tubal-peritoneal infertility is most frequent, with the prevalence of 42.5-80.5% in various estimates. Echohysterosalpingography is considered the today’s “gold standard” in tubal-peritoneal infertility diagnosis in women. This method is known to possess a series of limitations and adverse consequences due to painful sensations during and after check-ups that psychologically afflict women.Objectives. An overview of current methods for inspecting fallopian tubes in reproductively impaired patients to inform promising diagnostic research.Methods. Publications were mined and analysed in the PubMed, eLibrary, Web of Science, Cochrane Library and Cyberleninka electronic databases. The query terms were: echohysterosalpingography [эхогистеросальпингография], echohysterography [эхогистерография], infertility [бесплодие], pregnancy planning [планирование беременности], fallopian patency [проходимость маточных труб], ultrasonic diagnosis [ультразвуковая диагностика], submucous myomatous node [субмукозный миоматозный узел], incompetent uterine scar [несостоятельный рубец на матке], niche [ниша]. The topic selected was female infertility, particularly, the use of echohysterosalpingography in fallopian diagnosis in reproductively impaired women.Results. The review covers 52 sources of the total 118 analysed. Current published evidence and its review identify a notable success of imaging techniques in the fallopian tube diagnosis in women with reproductive problems. The continually developing echohysterosalpingography technique is considered more promising for routine use. Techniques gain more value in analyses of implantation failures. The main challenges in current radiodiagnosis and monitoring of fallopian lesions at a background therapy are the inspection standardisation, disease classification, imaging diagnostic accuracy and prognostic value evaluation in patients with reproductive loss and infertility.Conclusion. The prospective routes of research comprise the definition of optimal check-up terms, echohysterography and echohysterosalpingography diagnostic criteria descriptiveness, improving prognosis in the carrying of pregnancy and treatment efficacy control. A timely and accurate diagnosis of uterus and fallopian tubes is of paramount importance to sustain the women’s reproductive health