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Approximate decomposition for the solution of boundary value problems for elliptic systems arising in mathematical models of layered structures

We consider oscillations in cylindrical slotted resonators formed by combinations of rectangular domains with several slots cut in the walls using the methods of approximate semi-inversion of integral operator-valued functions with a logarithmic singularity of the kernel. The initial boundary value problems for the Helmholtz equation are reduced to Fredholm integral equations and systems of integral equations of the first kind with a logarithmic singularity. In the case of narrow slots, the dispersion equations are obtained and evaluated using perturbations and the small-parameter method. Eigenfrequencies and eigenfields are calculated explicitly. The values of geometrical and material parameters are determined that lead to the interaction of oscillations. The results obtained are used for improving the design of filters and switches on the basis of simple model prototype structures.

The Russian Academy of Sciences and Federal Space Agency, together with the participation of many international organizations, worked toward the launch of the RadioAstron orbiting space observatory with its onboard 10-m reflector radio telescope from the Baikonur cosmodrome on July 18, 2011. Together with some of the largest ground-based radio telescopes and a set of stations for tracking, collecting, and reducing the data obtained, this space radio telescope forms a multi-antenna ground-space radio interferometer with extremely long baselines, making it possible for the first time to study various objects in the Universe with angular resolutions a million times better than is possible with the human eye. The project is targeted at systematic studies of compact radio-emitting sources and their dynamics. Objects to be studied include supermassive black holes, accretion disks, and relativistic jets in active galactic nuclei, stellar-mass black holes, neutron stars and hypothetical quark stars, regions of formation of stars and planetary systems in our and other galaxies, interplanetary and interstellar plasma, and the gravitational field of the Earth. The results of ground-based and inflight tests of the space radio telescope carried out in both autonomous and ground-space interferometric regimes are reported. The derived characteristics are in agreement with the main requirements of the project. The astrophysical science program has begun., 54 pages, 11 figures; published by Astronomicheskij Zhurnal (in Russian) and Astronomy Reports (in English)

Previous studies have shown that IL-2-stimulated peripheral blood mononuclear cells (PBMC) produce IL-1 beta and TNF alpha and that monocytes are the primary source of these IL-2-inducible cytokines. In this report, we provide evidence that monocytes are not the only source. We examined cytokine production by IL-2-treated, nonmonocytic PBMC and found that a population of nonadherent low-density cells (NLDC) produced both IL-1 beta and TNF alpha in response to IL-2. IL-1 beta was synthesized by IL-2-treated NLDC as the 35-kDa intracellular precursor (pro-IL-1 beta), but was neither secreted nor processed to the mature 17-kDa form of the molecule. To determine which cells within the NLDC population generated pro-IL-1 beta and TNF alpha in response to IL-2, we positively selected NK cells and T cells, the two major components of NLDC, using specific monoclonal antibodies. Although IL-2-treated CD16+ NK cells produced TNF alpha and transcribed IL-1 beta mRNA, they did not synthesize the IL-1 beta protein. Conversely, LPS-treated CD16+ and IL-2-treated CD4+ and CD5+ NLDC produced elevated levels of both TNF alpha and IL-1 beta. Our findings illustrate the complex nature of IL-1 beta production by IL-2-stimulated PBMC and suggest that the factors controlling IL-1 beta gene transcription and translation, as well as secretion and processing, vary widely as a function of cell type and stimulus.

Twenty isolates of Fusarium graminearum have been isolated from infested grain. When laying hens were fed with biomass of most isolates, the quality of eggs deteriorated. It was found that all the isolated produced a yellow-orange metabolite with an antibiotic activity against mycelial fungi and yeasts. The metabolite was identified by physico-chemical methods as the dimeric naphthoquinone aurofusarin. The production of the other mycotoxins zearalenone and deoxynivalenol by the fungal isolates did not evoke the syndrome of egg quality deterioration.

This paper addresses the application of the operator-valued function and small-parameter methods to the analysis of the wave propagation and interaction in a family of slotted waveguides. For narrow slots, the eigenwaves and field distributions in the cross-sectional domains are calculated as segments of asymptotic series in powers of the characteristic small parameter of the problems. For larger slots, the method of infinite-matrix (summation) equations is applied. The results show that the interaction of waves occurs in slotted structures and that semi-analytical methods are an efficient tool to analyse this phenomenon.

Diallyl thiosulfinate (allicin) is the agent found in garlic which is responsible for the antibacterial and antifungal activity of extracts of this plant. The effect of bacteriostatic concentrations of allicin (0.2 to 0.5 mM) on the growth of Salmonella typhimurium revealed a pattern of inhibition characterized by: (i) a lag of approximately 15 min between addition of allicin and onset of inhibition, (ii) a transitory inhibition phase whose duration was proportional to allicin concentration and inversely proportional to culture density, (iii) a resumed growth phase which showed a lower rate of growth than in uninhibited controls, and (iv) an entry into stationary phase at a lower culture density. Whereas DNA and protein syntheses showed a delayed and partial inhibition by allicin, inhibition of RNA synthesis was immediate and total, suggesting that this is the primary target of allicin action.