Correction of distortions in color images based on parametric identification

The paper under consideration deals with a certain information technology for correction of color digital images distortions. These distortions result from image registration process and interaction with lighting environment. In this study, we consider the basic scheme of the correction technology for various types of distortions. The scheme consists of three main stages: detection of distorted areas, identifying of color distortion model, and constructing the correction color mapping. Efficient algorithms are proposed for each stage. The results obtained for some kinds of distortions are given in the paper.     

Nucleotide sequence and genomic organization of repeating units of the AT-rich family or repeats in the diploid wheat Triticum monococcum L

In diploid wheat Triticum monococcum L., a novel family of AT-rich repeated DNA sequences arranged in clusters of tandem arrays of 560-bp fragments is described. The nucleotide sequence of a 556-bp repeat unit was determined. The basic structural unit of this repeated DNA family contains subrepeats with the main motif AAACATTGTTAC. This type of repetitive DNA sequence could evolve via tandem amplification of short subrepeats with some subsequent divergence, and/or via recombination with unique sequences. Structural organization of homologous sequences, revealed by blot hybridization in other representatives of the Triticeae tribe, suggest that this family of repeated DNA is genome-specific.     

Effect of electron irradiation on the formation of silver nanoclusters in photothermorefractive glasses

The dynamics of formation of silver nanocrystals under the action of an electron beam in the near-surface layer of photothermorefractive glasses containing Ag⁺ ions has been experimentally studied. It is shown that the irradiation by electrons leads to the field-induced diffusion of Ag⁺ ions and the appearance of primary silver nanoclusters. The role of nanostructures of the core-shell type in the formation of these nanoclusters and the subsequent growth of metallic silver nanoparticles with plasmon resonances is determined.     

Influence of Glass Composition on the Refractive Index Change upon Photothermoinduced Crystallization

The influence of the main components (SiO₂, Al₂O₃, ZnO, and Na₂O) of a photothermorefractive glass matrix and Br^–ions on the change in the refractive index is studied in the course of photothermoinduced crystallization in glasses. The optimum concentrations of these components at which the change in the refractive index is maximum are determined. The regularities revealed are explained within the modern concepts of the structure of polychromatic glasses and the nature of the photothermorefractive effect.     

Crosslinking in solutions of chitosan in the presence of a crosslinking reagent for production of fibre biocatalysts

Gelation in soltuion sof chitosan in the prfesence of a bifunctional crosslinking reagent of glutaraldehyde and protein was investigated. It was shown that the gelation rate, strength, and equilibrium moisture absorption fo the gel formed are determined by the conditions of crosslinking the chitosan (MW of chitosan, pH, and GA/—NH₂ ratio). The systems studied were used in fabrication of fibre biocvatalysts by pformation of an enzyme-containing gel membrane on the surface of coarse calico. __________ Translated from Khimicheskie Volokna, No. 2, pp. 9–11, March–April, 2006.