The problem of spreading of harmful emissions from the dried part of the Aral Sea is extremely relevant for the Central Asian region, but it is also important for other countries of the near and far abroad in view of the transboundary transport of pollutants in the atmosphere. In order to solve the problem of predicting the distribution of the concentration of air pollutants, researchers are usually use mathematical tools. Modelling the processes of transport and diffusion of pollutants in the atmosphere claims to address various factors, such as weather and climate conditions, soil erosion, physic and mechanical properties of aerosol particles, etc. Thus, this study was aimed to develop a model and computational algorithm for solving the problem. The particular attention was paid to the description of wind erosion since most emissions in the Aral Sea region occur by the removal of salt-dust particles from the soil surface. There were conducted a series of computational experiments using the developed mathematical apparatus. The obtained results presented in the paper are illustrating the influence of various factors on the process of atmospheric dispersion. Comparison of the results of computational experiments with experimental data showed sufficient agreement, which confirms the adequacy of the developed mathematical model of the process of spreading of fine aerosol particles in the atmosphere.

The urgent problem related to solving the problems of monitoring and predicting the ecological state of the air basin in industrial regions is considered in the paper. It provides a brief review of scientific publications devoted to these problems. A mathematical model has been developed to study, predict and monitor the concentration of harmful substances in the atmosphere. The model takes into account weather and climate conditions, soil erosion, physicomechanical properties of aerosol particles, and other factors affecting the process under consideration as a whole; it is designed for optimal location of newly constructed production facilities.

ISRA (India) = 1.344 ISI (Dubai, UAE) = 0.829 GIF (Australia) = 0.564 JIF = 1.500 SECTION 2. Applied mathematics. Mathematical modeling.

In the general case, when modelling the process of air pollution dispersion, it is necessary to take into account factors associated with the interaction of air mass with the underlying earth surface or wind erosion. The main purpose of this work is to study the factors affecting the amount of particulates carried upward from the soil into the air due to wind erosion. The study of this aspect is very relevant for the analysis of environmental situation in the Aral region of Uzbekistan. The major share of harmful substances emission in Aral Sea region is undertaken by dust, salts and toxic chemicals blown up from dried bottom of the Aral Sea. Thus, in mathematical modelling of atmospheric dispersion process, it is necessary to take into account the physic and mechanical properties of the particles and basic forces acting on them. In the paper there are presented certain numerical calculations for studying the process of soil erosion depending on the air mass velocity of the atmosphere, the size and density of particles, and the acting forces. The basic forces that play a significant role in the process of soil erosion were determined by carried numerical calculations.

It is known that COVID-19 has an adverse effect on various organs and systems of the human body. In the available literature, there are isolated reports regarding the development of osteonecrosis after suffering COVID-19. These papers discuss the role of commonly used corticosteroids in the treatment of COVID-19 in the development of osteonecrosis. Our article presents clinical observations of four patients with bilateral osteonecrosis of the femoral heads after treatment with COVID-19. The doses of prednisolone in three patients were 4500 mg, 735 mg and 525 mg. One patient did not receive corticosteroids. Our data showed that osteonecrosis in COVID-19 survivors developed at a shorter time compared to osteonecrosis in patients without coronavirus infection. Two out of four patients had a positive family history (myocardial infarction, hypertension, thrombosis). It is possible that hereditary vascular factors played some role in the genesis of osteonecrosis of the femoral head. Further evidence is needed to understand the development of osteonecrosis after COVID-19. Probably, the development of the disease is synergistically affected by many factors, including steroid and ischemic