Cooperative effects in surfactant adsorption layers at water/alkane interfaces

In the present work, the properties of dodecyl dimethyl phosphine oxide (C12DMPO) at the water/decane interface are studied and compared with those obtained earlier at the interface to hexane. To simulate the interfacial behavior, a two-component thermodynamic model is proposed, which combines the equation of state and Frumkin isotherm for decane with the reorientation model involving the intrinsic compressibility for the surfactant. In this approach, the surface activity of decane is governed by its interaction with C12DMPO. The theory predicts the influence of decane on the decrease of the surface tension at a very low surfactant concentration for realistic values of the ratio of the adsorbed amounts of decane and surfactant. The surfactantrsquo;s distribution coefficient between the aqueous and decane phases is determined. Two types of adsorption systems were used: a decane drop immersed into the C12DMPO aqueous solution, and a water drop immersed into the C12DMPO solution in decane. To determine the distribution coefficient, a method based on the analysis of the transfer of C12DMPO between water and decane is also employed

Stimulating of entrepreneurs’ innovative activity in the Republic of Bashkortostan

The article views some aspects of promoting innovative activity in the Republic of Bashkortostan. The measures stimulating innovative activity have been grouped into blocks.1. Creating favorable conditions for innovative activity. 2. Increasing the population’s innovative activity. 3. Development of the system of scientific and production cooperation and innovation commercialization. 4. Investment support of innovative projects. 5. Development of innovative infrastructure. 6. Development of innovative small businesses. 7. Information provision of innovative activity. The main directions of implementing the above-mentioned conditions are: - lawmaking activity in the Republic, taking into consideration the federal legislation, international standards and traditions; - financial and tax inducement of scientific-technical and innovative activity; - international technological integration; - private-state partnership in the sphere of innovative activity. Recommendations are suggested, relating to the innovative policy activation for more efficient fulfillment of the key functions of the Republic’s scientific and research sector. The authors conclude that the Republic has all necessary preconditions for small entrepreneurship functioning: the natural conditions favorable for many kinds of economic activity, the forming local market infrastructure for small business servicing, and the availability of large enterprises and centers of economic activity.Keywords: entrepreneur, entrepreneurship, innovation, innovative activity, region, infrastructure, investments, stimulation, monitoring

The hemolytic propertiesof clinical isolates of Morganella morganii

Morganella morganii is a gram-negative bacterium from the Enterobacteriaceae family which causes a wide range of clinical infections sometimes with fatal consequences. It is known that more than 50% of isolates of M. morganii from clinical specimens have hemolytic activity that increase their virulence. Pore-forming toxins (PFT) represent the most common group of cytotoxic proteins which contribute the delivering of the bacterial proteins into host cells, loss of nutrients and ions by eukaryotic cells, as well as the exit of bacteria from phagosome into cytosol. In this study we investigated the hemolytic activity of two M. morganii strains. It has been shown that hemolytic activity for strain of M. morganii 4 is 3 times higher than for strain of M. morganii 1. The maximum hemolytic activity is observed in LB medium but synthesis of hemolysins is higher in synthetic urine. Finally, the PCR-analysis of 5 hypothetical hemolysin genes has shown that strain M. morganii 1 does not contain homologous of α-hemolysin from E. coli that may explain the observed differences in hemolytic activity of the investigated strains

Biosynthesis of the subtilisin-like serine proteinase of Bacillus intermedius under salt stress conditions

The biosynthesis of the subtilisin-like serine proteinase of Bacillus intermedius 3-19 by the recombinant strain Bacillus subtilis AJ73(pCS9) was found to be enhanced under salt stress conditions (growth in a medium containing 1 MNaCl and 0.25 M sodium citrate). In a recombinant strain of B. subtilis deficient in the regulatory proteins DegS and DegU, which control the synthesis of degradative enzymes, the expression of the proteinase gene was inhibited. In contrast, in the strain B. subtilis degU32(Hy), which provides for the overproduction of proteins positively regulated by the DegS-DegU system, the biosynthesis of the subtilisin-like proteinase of B. intermedius 3-19 increased by 6-10 fold. These data suggest that the DegS-DegU system is involved in the positive regulation of the expression of the subtilisin-like B. intermedius proteinase gene in recombinant B. subtilis strains. © Nauka/Interperiodica 2006

Structure Formation of the Surface Layer of Soil as a Way to Prevent a Wind and Water Erosion

The present work describes the results of a study of structuring ability of water-soluble polymers such as polydimethyl diallyl ammonium chloride, saponification product of polyacrylonitrile (uniflok) and their interpolymer complex. On the kinetics of growth of Rehbinder’s plastic durability of coagulation structure of soil concentrated suspensions the effect of water soluble polymers and interpolymer complexes on the structure formation in the dispersions was studied. It was determined that the process is a two-step process which was caused by the adsorption step process: the binding of macromolecules with the soil surface by the random segments and conformational changes of macromolecules in the adsorbed layer. It was found that the soil stability structured by polymers against wind and water erosion increased with the concentration of water-soluble polymers. This is due to the increase of the structure formation in concentrated suspensions of soil in the presence of water soluble polymers. On the basis of the results it can be concluded that the treatment of mineral dispersions by water-soluble polymers alone or in the form of the interpolymer complex leads to a significant reduction of dust-and run-off of soil particles. The PDMDAAC/uniflok interpolymer complex in comparison with polymers reduces intensively the deflation which has a great economic and ecological importance

Biosafety model of adenovirus infection: Effects of bacterial proteases for infection of human cells in vitro

To determine the antiviral activity of various biologically active compounds, the model of adenovirus infection on the basis of cell cultures of human HEK293A and recombinant adenovirus Ad-EGFP, expressing green fluorescent protein EGFP. Adenoviruses have a capsid size of 70-90 nm and are able to infect dividing and nondividing cells in vitro and in vivo. Recombinant adenoviruses are the replicative defect in the cells of humans and animals. The developed model allowed us to determine the effect of bacterial proteases in the infected cell cultures with adenovirus. This model can also be used for screening drugs with potential protivivovirusnoy activity

Salt stress induction of glutamyl endopeptidase biosynthesis in Bacillus intermedius

Bacteria from the genus Bacillus have evolved complicated regulatory networks to be protected from various environmental stresses, including sudden increase in salinity. Among these regulatory mechanisms is the DegS-DegU signal transduction system, which controls degradative enzyme synthesis and is involved in sensing salt stress in Bacillus subtilis. We report the study of biosynthesis regulation of Bacillus intermedius glutamyl endopeptidase under salt stress conditions. Salt stress during growth in medium containing 1-2.5 M NaCl, KCl or disodium succinate leads to the induction of glutamyl endopeptidase. Analysis of the regulatory region of the gene for B. intermedius glutamyl endopeptidase revealed the presence of a tentative target sequence for DegU control, AGATN10TTGAG. For the expression of the glutamyl endopeptidase gene, functional DegU protein is required. Thus, we suggest that expression of the gene for B. intermedius glutamyl endopeptidase may be controlled by a regulatory system analogous to DegS-DegU two-component system in B. subtilis. © 2005 Elsevier GmbH. All rights reserved