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From the second half of the 20th century and up to the present, the floodplain ecosystem has been under high anthropogenic pressure. During this period, various types of disruption appeared in the inner-landscape habitats as a result of human economic activity, which account for more than 50 % of the total area of the Oka River floodplain landscape. This paper conducts a biomorphological and taxonomic analysis of the flora of disrupted inner-landscape habitats, which are grouped into two types. The species composition of flora of disrupted habitats and natural communities of the floodplain during the period 1907-1910 and 1997-2005, which experienced low anthropogenic pressure, were compared. In the flora of inner-landscape disrupted habitats of types I and II, 92.3 % are common species of the flora of all disturbed habitats. It was established that native species play a key role in the formation of flora and vegetation of all the disrupted habitats. The role of adventive species in this process is less significant.

This article examines the long-term influence of the anthropogenic pressure complex on the floodplaincommunities of the Middle Oka. It has been established that as a result of prolonged application of high doses of mineralfertilizers during the change in the eco-topic conditions of the floodplain landscape, in connection with the interruptionof the regimes within the floodplain and alluviality, a pivotal change occurs in the structure of the plant communities under all analysed parameters.

Pathogenetic aspects of lymphopenia in various pathological conditions are studied. A statistical assessment of the incidence of lymphopenia in the world is given. It is shown that prolonged lymphopenia increases the risk of developing diseases of infectious genesis and an adverse outcome. A long-existing decrease in lymphocytes leads to the activation of opportunistic infections and becomes the basis for the development of malignant neoplasms and autoimmune pathology. Recombinant interleukin 2 (Roncoleukin®), filling the deficiency of endogenous interleukin 2, is a means of not only substitution, but also of inductive therapy. Restoring the regulatory effects of interleukin 2, Roncoleukin® levels the manifestations of lymphopenia and positively affects the dynamics and outcome of the disease.

A mathematical model is developed for the diffusion of hydrogen in steel on machining; this entails the solution of a second-order differential equation with variable coefficients. The initial and boundary conditions are determined. Numerical solution is based on the alternating-direction implicit method. The experimental temperature dependence of the effective diffusion coefficient for hydrogen is employed in modeling.

In this paper we propose an explicit finite-difference scheme to solve the American option pricing problem. It is based on front-fixing transformation that involves unknown free boundary to the equation. The proposed stable and consistent numerical scheme preserves positivity and monotonicity of the solution in accordance with the behavior of the exact solution. Numerical examples and comparison with other methods are included. This technique can be applied to some types of two-asset options after reducing the dimension. In the paper the front-fixing method is applied to exchange option pricing.

Yeast cell phenotype and morphology result from the interaction of two processes, polarized growth, on the one hand, and cytokinesis with subsequent division of the cell wall, on the other. Imbalance of the equilibrium of these two principal processes may lead to the occurrence of yeast morphological mutants that generate rough colonies. Two types of such mutants exist, Rgh and Rpm. The Rgh mutants have ellipsoid cells and either form chains or generate clumps at high frequency. These changes in heterothallic strains of saccharomyces occur due to recessive mutations in any of 11 non-linked genes. In homothallic strains of saccharomyces, the trait Rgh depends on the complementary interaction of one dominant and two recessive genes. Rpm mutants generate rough colonies, which contain elongated cells that give rise to pseudomycelium. The mutants obtained are recessive and occur in six non-linked genes. The Rpm mutants represent an example of the manifestation of mycelium-yeast dimorphism in fungi, and this case may be regarded as a simple morphogenetic model.