The aim of the article is to assess the level of aliphatic hydrocarbon (AHC) contamination in bottom sediments of the Azov–Black Sea coast of the Crimea, as well as to identify potential sources of its formation. Bottom sediment samples obtained from 19 stations during the research cruise of the R/V “Professor Vodyanitsky” (June 2020) were used as the material for this investigation. Sampling stations were located along the coast of the Crimean Peninsula and the Caucasus coastlines (the Black and Azov Seas). N-hexane extracts of sediments were studied by gas chromatography to determine the AHC amount and composition. It was established that AHC concentrations in the study area varied from 1.30 to 127.8 mg/100 g. Generally, bottom sediments of the Black and Azov Seas were characterized by low AHC contents, while increased AHC contents were found in the outer harbor of Sevastopol and Yalta regions. To identify potential hydrocarbon sources, various hydrocarbon markers were used. In most of the study areas, n-alkane composition was determined by similar sources of inputs and organic compound transformation. At the same time, oil pollution linked with use of fuel was recorded almost everywhere.

The article presents the analysis and prospects of commercial aquaculture in the southern regions of Russia. Rostov and Astrakhan region and Krasnodar Krai are the leaders in commercial fish production. Rostov region annually grows 23-24 thousand tons. In Krasnodar region in the period from 2018 to 2022 there was a 15% growth of avcaculture production and in 2022 it was 23,3 thousand tons. In the Astrakhan region from 2018 to 2021 there was a decrease in this indicator by 13%, but in 2022 the volume of production in the region increased to 20.5 thousand tons. Absolute parameters in Stavropol Krai (11.8-12.3 thousand tons) Kabardino-Balkarian Republic (2.5-3.3 thousand tons) and Volgograd Oblast (2.3-2.5 thousand tons) remained almost unchanged. Significant growth of relative production parameters was noted in the Republic of Dagestan, the Republic of North Ossetia-Alania and the Republic of Crimea. The main objects of cultivation in the South of Russia are carp fish. A substantiation of creating a state-owned structure ensuring practical interaction between economic entities, executive bodies of state power, scientific and educational institutions is offered.

Introduction. In modern Russian historiography, an unacceptable situation has developed since the Soviet period in the history of the Cossacks has not yet become the subject of sufficient research attention; therefore, a common vision of the reference points of scientific research has not taken shape. The article is aimed at studying the methodological and historiographic plots of the Soviet history of the Cossacks of the South of Russia in order to clarify unexplored plots and aspects, to determine further directions of scientific research. Methods and materials. We have at our disposal a number of significant historiographic facts that allow us to identify current historiographic trends in the study of the Soviet history of the Cossacks of the South of Russia. To do this, the article uses the method of system analysis and expert evaluation of historiographic facts, which provides the final argumentative logos. In a number of cases, the authors draw on archival materials to clarify and reinforce their positions. Analysis. The Soviet period in the history of the Cossacks of the South of Russia has been studied extremely unevenly, and this leads to distortions in the interpretation of individual problems. Excessive fascination of many modern authors with stories of decossackization creates a historical background of the tragic existence of the Cossacks in the Soviet era. As a result, the mass heroism of the Cossacks during the Great Patriotic War is involuntarily obscured by the difficult historical past and the plots of Cossack collaborationism. Decades of life of many generations of Cossacks are voluntarily or involuntarily deleted from the general history of the Cossacks. Therefore, it is important to identify the whole range of topical issues in the study of the Soviet period in the history of the Cossacks of the South of Russia, where there is also a positive historical experience. Results. The article outlines the established stages in the historiography of the Cossacks of the Soviet era and provides examples of specific studies on certain issues of Cossack history. The main directions of further research are determined with brief characteristics of the named plots. Contribution of authors. The creation of the concept of the article, the development and description of the research methodology, the conceptual apparatus, and the analysis of the involved content belongs to A.P. Skorik. The selection of archival materials and historiographic facts, as well as their primary analysis, was carried out by V.A. Bondarev. Conceptual editing, identification of a number of historiographical trends and addition of source materials with historiographic facts were carried out by G.G. Matishov. The final scientific and literary editing of the text of the article was carried out by A.P. Skorik and V.A. Bondarev.

Loess-paleosol sequences are the most intensively studied terrestrial archives used for the reconstruction of Late Pleistocene environmental and climatic changes in the Azov Sea region, southwest Russia. Here we present a refined chronostratigraphy and a multiproxy record of Late Pleistocene environmental dynamics of the most complete and representative loess–paleosol sequences (Beglitsa and Chumbur-Kosa sections) from the Azov Sea region. We propose a new chronostratigraphy following the Chinese and Danubean loess stratigraphic models that refines the subdivision of the Last Interglacial paleosol (S1) complex in two Azov Sea sites, resolve the uncertainty of the stratigraphic position of the weakly developed paleosol (L1SSm) in Beglitsa section, and allow for direct correlation of the Azov Sea sections with those in the Danube Basin and the Chinese Loess Plateau. More importantly, it may serve as a basis for better constraining local and regional chronostratigraphic correlations, and facilitate the interpretation of climatic connections and possible forcing mechanisms responsible for the climatic trends in the region. In addition, a general succession of environmental dynamics is reconstructed from these two vital sections, which is broadly consistent with other loess records in the Dnieper Lowland and Lower Danube Basin, demonstrating similar climatic trends at Glacial–Interglacial time scales. Furthermore, our results have important implications for the chronostratigraphic representativeness of Beglitsa as a key regional loess section and for the reconstruction of the temporal and spatial evolution of Late Pleistocene climate in the Azov Sea region.

Article present the main results of the investigations deal withthe program of the Presidium Russian Academy of Science “Bioresourcesof the Arctic seas of Russia: current state, the effectof natural changes and anthropogenic impacts, scientific foundations and perspectives for use”and linked researches.

The article presents the results of the expeditionary investigations carried out from the “50 Let Pobedy” nuclear icebreaker to research the present physiographic conditions of the Barents Sea and the Arctic Ocean and estimations of the main features that may reflect the global climatic variability of the seas and oceans of the Arctic. The observations of the ice lanes, hummocks, puddles, icebergs, the thickness and closeness of ice allowed us to make a real picture of the ice cover in the second half of August 2017. The zonal distribution of drifting ice, air temperature, temperature and salinity of seawater is shown. The results of observations and conclusions presented in the article reflect the simultaneous situation of the most western part of the Central Arctic adjacent to the Norwegian-Greenland basin. The analysis of new data of the structure and distribution of sea ice and icebergs gives a reason to present a number of general conclusions about the variability of ice thickness and closeness, relative age, the ratio of the area covered with ice and pure water. Recommendations about the development of new satellite systems for a reliable assessment of the seasonal and inter-annual dynamics of the area and thickness of sea ice in the Arctic Ocean are presented.

A spectrum of differentially expressed microRNAs was determined by the massively parallel sequencing method in normal healthy prostate tissues, in hormone-dependent prostate cancer samples, and in the LNCaP and DU145 cell lines. A set of microRNAs in tumors and prostate cancer (PCa) cell lines was identified on the basis of the changes in expression compared with that in normal prostate tissues. Twenty-seven aberrantly expressed microRNAs were detected in tumor tissues and ten of them showed significant changes in expression in LNCaP and DU145 cells. Seven of them demonstrated the change of the expression in the same direction in all the tumor samples as well as in the PCa cell lines. The expression of miR-148a changed in DU145 cells in the opposite direction compared with that in LNCaP cells and tumors. The expression of let-7c, let-7b, miR-99a, miR-125b-2, miR-100, miR-10a, and miR-31 was reversed in DU145 cells compared with LNCaP cells. However, these microRNAs exhibited no significant changes in expression in tumors. It turns out that the target of miR-148a, let-7b, and microRNAs, included in the miR-99a/let-7c/miR-125b-2 cluster, the expression of which increased in LNCaP cells and decreased in DU145 cells, is the insulin-like growth factor receptor gene 1 (IGF1R). The obtained data make it possible to assume that the differences in the effect of microRNAs in cell lines are connected with their repressive influence on IGF1R expression in hormone-sensitive LNCaP cells and an absence of such influence in the hormone-independent DU145 cell line.

This year marks the 75 th anniversary of Order 227 of July 28, 1942, known as the Order "No one step back!".This Order reflected the crisis situation on the southern flank of the Soviet-German front and the disastrous results of the Red Army defeats.The Order outlined severe measures for establishing discipline in the troops and for preventing unauthorized retreat.Distributed to the Combat Army, the Order provoked contradictory, in most cases positive assessments by soldiers and commanders who fought in the large bend of the Don at that time.6 penal battalions and more than 30 penal companies, several dozens of barrier troops were formed and took part in battles in the large bend of the Don in the August-September of 1942.G.G. Matishov characterizes the circumstances of issue of Order 227 and draws the conclusion.V.I.Afanasenko reveals the data about penal units in the large bend of the Don in the summer and autumn of 1942.

Using multiple parallel sequencing on Illumina platform, we identified eight microRNAs that showed significant opposite changes of gene expression in cells of the hormone-sensitive LNCaP prostate cancer cell line and in cells of the hormone-resistant DU-145 cell line, in comparison to the microRNA expression in the normal prostate tissue cells. We found that the insulin-like growth factor 1 receptor (IGF1R) gene is a target of five microRNAs whose expression is increased in LNCaP cells and reduced in DU-145 cells.

One the most complete megadatabases for the period of 1914–2010 is used to study the interannual dynamics of salinity and temperature of Caspian Sea waters. Periods with relatively stable sea levels but different climatic conditions are considered. Average interannual climatic salinity and temperature profiles of water and corresponding anomalies are analyzed. Quantitative and qualitative changes in the structure of seawater that took place during the 20th century are described. Schemes of water exchange between particular sea regions for different sea levels are proposed.

The article studies the history of the interaction between the Ukrainian national movement and Russian state power in the period from the Revolution of 1905-1907 and The World War I. The authors analyze the main stages of the Ukrainian movement evolution in early XX century, and show the role of Russian nationalist organizations, firstly the Kiev Club of Russian Nationalists, in the elaboration of the governmental policy in the Ukrainian question. The principle part of the article deals with the genesis of the Stolypin circular of 1910 on the non-Russian societies and its impact on the Ukrainian movement.

We studied microRNA gene expression in HeLa cells following exposure for 6 h and 8 days to Co60 gamma rays at a dose of 4 Gy using an approach of large-scale parallel DNA sequencing. We identified 12 microRNAs with aberrant expression which were maintained in cell generations. The analysis of radiation-induced aberrant expression of pre-microRNAs made it possible to assess the importance of nuclear and cytoplasmic stages of microRNA biogenesis for preservation of its aberrant expression. On cell treatment by 5-azacytidine, aberrant expression was maintained only in two microRNAs: miR-21-3p and miR-422a, which demonstrated an increase in expression. Radiation-induced decrease in expression in ten examined microRNAs was dependent on DNA demethylation. At the same time, expression in a microRNA set, which demonstrated inheritable alteration of the expression after gamma-radiation exposure in the untreated cells, was not dependent or was weakly dependent on DNA methylation. The obtained results suggest that ionizing radiation induces aberrant DNA methylation, which affects inherited expression changes in microRNAs in cell generations after exposure to the mutagen.