A novel method for magnetohydrodynamic simulations and its first applications in astrophysics and cosmology on high performance computational systems

Magnetic fields are one of the most important phenomena in science and engineering, as they are present on almost every scale in nature, ranging from atomic magnetic moments to the intergalactic space, and are used in applications ranging from Magnetic Resonance Imaging to nuclear fusion. In this work we first present a novel powerful method for high performance magnetohydrodynamic (MHD) calculations which is based on kinetic schemes. In particular, using it, it is possible to derive the MHD equations directly from the Boltzmann Equation without the necessity of an ad hoc introduction of terms related to electromagnetic interactions. With that at hand, we were then able to apply the method to one of the most important problems in present day astrophysics and cosmology, namely to the question of the origin and time evolution of Intergalactic Magnetic Fields. As for their origin, there are mainly two scenarios discussed in the literature – on the one hand the cosmological one, where the magnetic field is produced by some process in the very early Universe, and on the other hand the cosmological one, where a seed of the magnetic field is created during structure formation and then amplified by some dynamo effect. Here, we show first results of the aforementioned application of our method – on the one hand, concerning the astrophysical scenario, the simulation of galactic winds, i.e. the ejection of matter from galaxies which might also carry magnetic energy, and on the other hand, for the cosmological scenario, the time evolution of primordial magnetic fields and their possible imprints on the Cosmic Microwave Background (CMB)

Russian-Polish Relations at the Turn of the “Long XII Century”: from the “Pereyaslavl Crisis” to the Death of Roman Galitsky

This article is a continuation of the work “The Polish Vector in the Politics of Vladimir Monomakh and His  Successors: from the Lyubech Congress to the “Pereyaslavl Crisis”, published in the previous issue. The question of the system of Russian-Polish relations during the period of the onset of political fragmentation of Russia (since 1132) and a radical change in the balance of power relative to the Kiev principality is considered in the article. It is proved that the thesis of the religious factor as decisive in Russian-Polish relations does not correspond to the realities of the 30—90s of the 12th century. It is shown that the internal and external political circumstances of the 30—40s of the XII century forced Kiev and Krakow to come closer. It is emphasized that the trend towards rapprochement continues throughout the second half of the 12th century. Particular attention is paid to the nature  of Russian-Polish relations at the turn of the XII-XIII centuries. The authors note that the situation in Russian-Polish relations begins to change dramatically in the first decade of the 13th century. Evidence is given that the reasons for the cardinal changes were associated with the political course of the Galician-Volyn prince Roman Mstislavich and the results of the IV Crusade, which marked the beginning of the civilizational split in Europe

Polish Vector in Politics of Vladimir Monomakh and His Heirs: from the Lyubech Congress to the “Pereyaslavl Crisis”

The question of the system of Russian-Polish interaction during the period of temporary stabilization of political relations in Russia - from the Lyubech Congress (1097) to the end of the Kiev reign of Mstislav the Great (1125-1132) is considered in the article. The authors show that the 12th century is presented in historiography as a time of gradual growth of contradictions between two Christian civilizations, as a transitional period between the Great Schism of 1054 and the IV Crusade (1202- 1204). An attempt is made to consider the relationship between Russia and Poland of the indicated period outside the teleological approach. The authors provide evidence that the thesis of the religious factor as decisive in Russian-Polish relations does not correspond to the political realities of the 10- 30s of the XII century. It is shown that it was the ideological orientation of Vladimir Monomakh towards the crusading movement and the Holy Roman Empire that made it impossible for allied relations between Kiev and Krakow in the first quarter of the 12th century. It has been proved that there was no single policy of Rus towards Poland; the actions of the two sides were situational. The authors come to the conclusion that in Russia and Poland, competing political groups sought to implement their own strategies in relation to the neighboring state

The urban environment of Italy in prose of W. D. Howells

The Italian experiences of an American writer of the late nineteenth century, William Dean Howells (1837-1920) reflected in travelogues provide researchers of literature the opportunity to study the genesis of his work in the paradigm of the culture of the United States. Accompanying him throughout life, they were the aesthetic basis for literary work of Howells. The influence of Italian works of art and literature can be seen in the choice of the individual style of the writer. Of special interest is the influence of the process of the creative development of American writer on his attitude to changing environment in the capital and the provincial towns of Italy. The topicality of this work is associated with the peculiarities of artistic interpretations of the different cultural environment through the author's perception of reality. The mental concept of "another" life, the recognition of the specificity of the foreign country" often take place in the process of reading the literary works of different genres. In prose of W. D. Howells the perception of the city is connected with the author's point of view on the depicted object, so the leading method in the study was the biographical. This is the first time in the Russian literature of XXI century that the travelogues by W. D. Howells are analyzed, the main motives of the narration are identified, the archetypal images, expressed in literary form, are determined. Fiction affects the formation of the cultural image of the city, the perception of its environment, plunging into the epicenter of the described lives of citizens. The practical significance of the research of the cultural phenomenon of the city is to identify the specific features, forms and techniques creating its image, enclosed in the space-time continuum of the works of W. D. Howells

Acute respiratory infections of concomitant etiology in children

Acute respiratory infections (ARIs) still represent a considerable challenge in the infectious pathology patterns. ARIs are included in the list of diseases with the greatest economic importance in the Russian Federation. According to the State Report on Sanitary and Epidemiological Welfare of Population in the Russian Federation in 2020, ARIs hold a dominant position in the infectious and parasitic disease patterns. The issue of concomitant infection is extremely topical today. Three scenarios of interaction between respiratory causative pathogens may develop in co-infections: synergism (more severe progress of a disease as compared to mono-infections), antagonism (milder progress of an infectious disease) or indifference (absence of interaction between two infectious pathogens, as a result of which a disease develops as two separate infections). A clinical symptom presentation of a disease may be distorted, as new symptoms that are not typical of the traditional progression of each of the infections may appear. In clinical practice, antibacterial therapy is often prescribed in cases where etiological infectious agents are not identified, and a reference point is the clinical characteristics of a disease and the severity of patient's condition that is most frequently caused by intoxication symptoms and intensity of feverish reaction and is exhibiting similar symptoms in viral and bacterial ARIs. That is why the rapid identification of the causative agents can help avoid irrational therapy and polypragmasia. The article provides a clinical case of the treatment of ARI of concomitant etiology which required a differentiated approach and prescription of an antiviral drug

INVESTIGATION OF CENTRAL HEMODYNAMICS VIA RIGHT HEART AND PULMONARY ARTERY CATHETERIZATION IN PATIENTS WITH SYSTEMIC CONNECTIVE TISSUE DISEASES

Pulmonary arterial hypertension (PAH) associated with systemic connective tissue diseases (SCTD) is a poor prognostic manifestation of the latter that result in death if untreated. The invasive determination of hemodynamic parameters is prominent in diagnosing the disease and determining its treatment policy and prognosis.Objective: to analyze the results of catheterization in PAH-SCTD patients admitted to the V.A. Nasonova Research Institute of Rheumatology.Subjects and methods. The investigation included 59 patients admitted to the V.A. Nasonova Research Institute of Rheumatology from September 2009 to September 2014. PAH was diagnosed in accordance with the conventional guidelines. All the patients underwent right heart and pulmonary artery (PA) catheterization at the diagnosis and over time during treatment.Results and discussion. All the patients included in the trial met the pre-capillary pulmonary hypertension (PH) criteria: mean pulmonary artery pressure (MPAP) ≥25 mm Hg; and PA wedge pressure (PAWP) <15 mm Hg. The exclusion of other causes of PH (pulmonary fibrosis, left heart disease, and thromboembolism), as well as a high transpulmonary pressure gradient >15 mm Hg and pulmonary vascular resistance (PVR) >3 Wood units could diagnose PAH in all our patients. There was a statistically highly significant association between pathological hemodynamic changes and functional class (FC). FC was found to be most closely correlated with right atrial pressure (RAP), cardiac output (CO), PVR, and cardiac index (CI). Among the most common manifestations of heart failure, only the presence of peripheral edemas was associated with worse hemodynamic parameters in PAH. It should be noted that out of two biomarkers (N-terminal pro-brain natriuretic peptide and uric acid), the former is largely related to the magnitude of changes in hemodynamic factors. The critical values of hemodynamic parameters were due to extreme edema – anasarca (RAP >17 mm Hg, PVR >20 Wood units, CI <14 ml/m2). Analysis of clinical and instrumental parameters in relation to FC revealed a linear relationship of RAP, CO, and PVR between the level of these parameters and FC; moreover, the highest correlation coefficients were observed for the hemodynamic parameters characterizing right ventricular systolic function. It is remarkable that no MPAP changes were found; only patients with FC IV showed its slight increase (from 51±8 to 55±8 mm Hg; р = 0.087). PAWP remained unchanged regardless of FC. Conclusion. Thus, the hemodynamic parameters determined in patients with PAH-SCTD during right heart and LA catheterization are closely related to the manifestations of respiratory and heart failure, the biomarkers, and FC of PAH

Invading the North: Dispersal of Nearctic treehopper Stictocephala bisonia (Hemiptera: Cicadomorpha: Membracidae) in European Russia

In recent years, the problem of distribution and expansion of new territories by invasive species has become global. The publication analyses the current distribution of Nearctic treehopper Stictocephala bisonia in the European part of Russia. It is a North American species which was introduced into Europe over 100 years ago, but only in the last 20-30 years has it been actively spreading in the continent. In the European part of Russia, the Nearctic treehopper has been known since 1992 from the Rostov region and since 1996 from the Krasnodar Krai. At present the species is reliably registered in 26 regions. The major part of observations (185, 82.2%) is made in the period from 2020 to 2022. Currently, the northern border of distribution is the city of Nizhny Novgorod. In the northeast, the range of the species reaches the Republic of Tatarstan, to the east of the Republic of Tatarstan and the Republic of Bashkortostan, the hopper has not yet been observed. Imagoes are observed in the southern regions beginning in the third decade of June. The maximum number of observations falls on the second and third decade of July and August

Pseudomembranous colitis complicated by toxic megacolon in oncological patients

In recent years, information on the increase in the incidence of  infection associated with Clostridioides difficile (CDI) has appeared in the literature. It is known that C. difficile which causes pseudomembranous colitis (PMC) most often affects debilitated patients who receive treatment for the main pathology for a long time. That is why PMC is most common in cancer patients receiving long-term and aggressive anticancer treatment, which is often accompanied by the use of several courses of antibiotics. The result of the irrational use of antibiotics, incorrect PMC therapy may be the  formation of toxic megacolon, intestinal perforation, sepsis, which in turn is fraught with a fatal outcome. It is this state of affairs that aroused our interest in the study of this topic. The steady increase in the incidence of Clostridioides difficile infection makes it particularly relevant to study CDI problem in relation to cancer patients, since they most often have a wide range of risk factors for developing clostridial infection. The article presents an overview of domestic and foreign sources describing this pathology, discusses epidemiology, pathogenesis, clinical picture and current understanding of the CDI treatment. At the end of the review, we present a case of successful treatment of pseudomembranous colitis after stoma closure, which was complicated by the development of toxic megacolon. Colproctectomy was performed as part of the complex treatment of this pathology. The patient received respiratory, renal replacement, hepatoprotective, antibiotic and antifungal therapy and other treatments