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Lake outbursts floods is belonging to the hydrometeorological hazards. They occur as a result of destruction of snow-ice or earth dams and are most typical for lakes of alpine and polar regions. Glacial lakes outbursts floods (GLOF) are widely spread on water bodies of Antarctic oases. Methods for GLOF’s hazard assessment include monitoring, component analysis, point-by-point estimates, etc.) often overestimate the degree of the GLOF’s hazard compare to the real situation. The article presents the first experience of using the method of constructing composite indices (CI) based on territorial determinants for assessing the GLOF’s hazard. The case study of using of CI on water bodies located in the Larsemann Hills Oasis (Brocknes Peninsula, East Antarctica) is presented in the article. The study is based on the incito data obtained by the authors and the archival materials of the Russian Antarctic Expedition (RAE) in 2008–2021, collected in the PAULAS database. The calculations of CI show that the results are generally consistent with the in-cito measurements. The results are presented as maps showing the degree of GLOF’s hazard and the most vulnerable sections of the routes connecting wintering stations to the airfield. The intervals of changes for most of the considered criteria, used for CI calculation, were determined by expert method, and, therefore, largely depended on the experience of researchers and their understanding of the natural processes. The future studies will be supposed to refine and possibly supplement the list of criteria. Nevertheless, in the conditions of shortage of water level field measurements, the considered method can be used to assess the GLOF’s hazard of poorly studied and unstudied water bodies not only of Antarctic oases, but also of high-mountain glacial lakes.

The electro-erosive wheel dressing exerts a significant impact on the machining accuracy of an article and the efficiency of the profile grinding process. To effectively control machining accuracy, the most important is the error due to the wear of a diamond wheel. The wheel should be dressed when wear approaches to the border but does not go beyond the tolerance field. This would reduce the number of defects at machining and bring down the utilization of diamonds. In addition, this reduces the dressingtime and, therefore, improves the efficiency of profile diamond grinding. The paper reports the methodology and results of an experimental study into the wear of profiled diamond wheels. The specific utilization of diamonds was examined on the grinding wheels of the direct profile. The amount of a wheel linear wear was measured by a contactless method applying a special device based on the use of eddy current sensors. This was followed by determining the integrated amount of the worn volume of a diamond layer; after that, the weight of the used diamonds was measured. The mass of the sanded material was determined by weighing it before and after machining. A mathematical method of planning and analysis of experiments was used to establish the functional dependence of the specific utilization of diamonds on the technological machining modes and the diamond layer parameters. The result of regression analysis is the derived functional dependence of diamond specific utilization on the following factors: the concentration of diamonds in a wheel, the grit of the tool, the grinding wheel velocity, the depth of grinding, and the speed of an article. To determine the patterns of wear of the shaped diamond wheel, we received an imprint of its profile on a control plate made from a solid alloy and measured the coordinates of the points of the working part of the profile relative to the non-utilized areas. Determining the difference of coordinates before and after the experiment has helped find the amount of radial wear of the grinding wheel at the appropriate profile point

The importance of yolk antibodies (IgY) for their use in the diagnosis and treatment of human diseases is shown. The structural features of IgY compared to human immunoglobulins were studied. The disadvantages of obtaining hyperimmune sera from mammalian animals were revealed. A feature of IgY is its resistance to trypsin and chymotrypsin, which can contribute to more effective treatment of diseases. Data on optimization of the technology for obtaining yolk antibodies (IgY) from various bird species are presented. It is shown that 25-50 mg of highly purified immunoglobulin can be obtained from one bird egg. Obtaining immunoglobulins from eggs is more humane than using mammals for this purpose. Compared to ion exchange chromatography, gel chromatography, and ultrafiltration, the methods of precipitation with various chemicals (ammonium sulfate) were found to be simpler in terms of methodology. The results of electrophoresis revealed two types of proteins with a molecular weight of about 65 kDa and 30 kDa, which corresponds to the mass of the «heavy» and «light» IgY chains. Quail species Coturnix coturnix japonica as a producer of biological raw materials for the production of diagnostic immunoglobulins have great advantages over chickens (Gallus domesticus).

Natural waters are polluted by sewage, industrial and transport waste leads to a decrease the oxygen content in the water and the disappearance of valuable fish species. As a result, the eutrophy of the reservoir develops - the saturation of reservoirs with biogenic elements, accompanied by an increase in the biological productivity of water basins. The purpose of the work was to study the bioecological state of water basins in the Luga district of the Leningrad region, the prospects for de-eutrophication. The monitoring data of water bodies were studied and factors influencing the bioecological state of water bodies were considered. Physicochemical, sanitary and microbiological, parasitological and toxicological research methods were used in the work. Objects of research: the rivers Obla and Svinechnaya; lakes Toloni and Omchino. All this is a very unfavorable factor and indicates strong water pollution. To combat the eutrophication of water bodies, preventive and regulatory measures are used. A promising prevention of eutrophication is a biotechnological method, including the cultivation of plants in the coastal zone, breeding of herbivorous fish, the use of the method of algolization (introduction of a chlorella suspension).