This paper presents the mutual time -marching method to predict the aeroelastic stability of an oscillating blade row in 3D transonic flow. The ideal gas flow through a Made row is governed by the time dependent Euler equations in conservative form which are integrated by using the explicit monotonous second order accurate Godunov-Kolgan finite volume scheme and moving hybrid H-O grid. The structure analysis uses the medal approach and 3D finite element dynamic model of blade. The blade movement is assumed as a linear combination of the ftrst modes of blade natural oscillations with the modal coefficients depending on time. To demonstrate the capability and correctness of the method, two experimentally investigated test cases have been selected, in which the blades had performed tuned harmonic bending or torsional vibrations (The 1 st and 4" standard configurations of the "Workshop on Aeroelasticity in Turbomachines" by Bolcs and Fransson, 1986). The calculated results of aeroelastic behaviour of the blade row (4* standard configuration), are presented over a wide frequency range under different start regimes of interblade phase angle.

In real flows nonstationary phenomena connected with the circumferential non-uniformity of the main flow and those caused by oscillations of blades are observed only jointly. An understanding of the physics of the mutual interaction between gas flow and oscillating blades, and the development of predictive capabilities is essential for improved overall efficiency, durability and reliability. In the study presented the algorithm proposed involves the coupled solution of 3D unsteady flow through a turbine stage and dynamic problem for rotor blades motion by action of aerodynamic forces without separating of outer and inner flow fluctuations. The partially integrated method involves the solution of the fluid and structural equations separately, but information is exchanged at each time step, so that solution from one domain is used as boundary condition for the other domain. 3D transonic gas flow through the mutually moving stator and rotor blades with periodicity on the whole annulus is described by the unsteady Euler conservation equations, which are integrated using the explicit monotonous finite-volume difference scheme of Godunov-Kolgan. The structure analysis uses the modal approach and 3D finite element model of a blade. The blade moving is assumed to be constituted as a linear combination of the first natural modes of blade oscillations with the modal coefficients depending on time. There has been performed the calculation for the last stage of the steam turbine. The numerical results for unsteady aerodynamic forces due to stator-rotor interaction are compared with results obtained with taking into account the blades oscillations. It has investigated the mutual influence of both outer flow nonuniformity and blades oscillations. It has shown that amplitude-frequency spectrum of blade oscillations contains the high frequency harmonics, corresponding to rotor moving past one stator blade pitch, and low frequency harmonics caused by blade oscillations and flow nonuniformity downstream from the blade row. Moreover, the spectrum involves the harmonics which are not multiple to the rotation frequency.

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The effects of Ridostin on the transcription of IFN family genes in human fibroblasts and lymphocytes were studied by quantitative real-time PCR. The degree of gene induction by Ridostin was most pronounced in fibroblasts, and was significantly higher than the induction by Kagocel: transcription of IFN-β, oligoadenylate synthetase, and double-stranded RNA-dependent protein kinase genes increased by about 2000, 100, and 20 times, respectively. In lymphocytes, Ridostin also activated a wide variety of IFN family genes, including genes of IFN-β, IFN-γ, and IFN-dependent enzymes, but this induction was less pronounced than in the fibroblasts. It was shown that gene response in lymphocyte from a child with cancer is reduced in comparison with that of adult healthy participant. Ridostin, and even more so Reaferon up-regulated activities of β-actin, glycerophosphate dehydrogenase, and β2-microglobulin genes, thus making impossible or limiting their use as constitutive stable reference genes (standards) in PCR-assays of IFN and their inductors.