Status of the gasdynamic ion source for multipurpose operation (GISMO) development at IAP RAS.

A new experimental facility named GISMO (Gasdynamic Ion Source for Multipurpose Operation) was constructed at the IAP RAS to continue investigations in the field of gasdynamic ion sources. The source utilizes 28 GHz/10 kW gyrotron radiation for heating magnetically confined plasma. Magnetic field configuration provided by a fully permanent magnet system is much like a simple mirror trap. The GISMO source is aimed at the production of bright ion beams with hundreds of milliamperes current. The facility has been tested for continuous-wave (CW) operation with 2 kW of heating power to check durability of a microwave injection system and the plasma chamber. A 2-electrode extraction system with an integrated Einzel lens was designed for a formation of CW high current beam with up to 100 kV accelerating voltage. The first results on ion beam production at GISMO are presented together with the general progress status of the facility.

[Construction of the new Escherichia coli K-12 wild-type strain with improved growth characteristics for application in metabolic engineering].

MG1655 of Escherichia coli K-12 is frequently used in metabolic engineering as the wild-type strain. However, its two mutations, ilvG and rph-1 provide a negative effect on culture growth. The "polar effect" of rph-1 decreases the level of pyrE expression, causing partial auxotrophy for pyrimidines. Mutation ilvG leading to the appearance of Val(S) phenotype causes retardation of cell growth rate on media containing amino acids. In this work, the substitution of two loci in the genome of MG1655 with the recovery of the wild-type phenotype was accomplished. Gene rph(wt) from the chromosome of E. coli TG1 was marked via Red-dependent integration of DNA fragment carrying lambda attL-Cm(R)-lambda attR and transduced with phage P1 into MG1655; later, the Cm(R) marker was removed with the use of lambda Xis/Int recombinase. Parallel to this procedure, a spontaneous Val(R) mutant of E. coli MG1655 yielding colonies of maximal size on M9 medium with glucose in the presence of Val (50 microg/ml) was isolated. It was shown that a nucleotide deletion in the isolated Val(R) strain had been generated in the region of the identified E. coli K-12 ilvG mutation, which led to the recovery of the reading frame and active protein synthesis. This mutation named ilvG-15, which is the only reason for the Val(R) phenotype in the obtained strain, was transferred to MG1655-rph(wt) using cotransduction, by analogy to the transfer of rph(wt). Evaluation of rates of aerobically growing cells (microm, hour(-1)) on M9 medium with glucose produced the following values: 0.56, 0.69, and 0.73 for strains MG1655, MG1655-rph(wt), and MG1655-(rph(wt), ilvG-15), respectively.

[The incidence and structure of inflammatory diseases of the maxillofacial area based on data from the Surgical Department of Pediatric Dentistry of the 2d Clinic of the Tashkent Medical Institute]. / Chastota i struktura vospalitel'nykh zabolevanii cheliustno-litsevoi oblasti po materialam khirugicheskogo otdeleniia detskoi stomatologii pri 2-i klinike Tashkentskogo meditsinskogo instituta.

Reviews the results of studies of the incidence and structure of inflammatory diseases of the maxillofacial area over 5 years. Defines the major principles of medical rehabilitation of children suffering from inflammatory diseases. Validates the usefulness of special wards for purulent conditions at a department for pediatric oral surgery.

[Effect of polymeric modification on specific properties of soya bean inhibitor]. / O vliianii polimernoi modifikatsii na spetsificheskie svoistva ingibitora iz soevykh bobov.

Chemical modification of the trypsin inhibitor from soya beans by a hydrophilic synthetic copolymer of N-vinylpyrrolidone was studied. The optimal conditions for modification (pH, ratio of reactants, reaction time) were established. The soluble polymeric forms of the inhibitor differing in the number of covalent bonds with the copolymer were obtained. An affinity adsorbent for isolation of trypsin was prepared by adsorption of the polymeric form on silochrome.

[Denaturation of the alpha-amylase of Bacillus subtilis in an acid medium]. / Denaturatsiia alpha-amilazy Bacillus subtilis v kisloi srede.

By fractionation of purine compounds (sorbtion on the cation exchange resin KU-2 (H+), extraction, precipitation of purine compounds as Ag-complexes) a "purine fraction" of the culture liquid epiphytic bacteria No. 703 isolated from barley overground organs was obtained. The presence of isopentenyl cytokinins was demonstrated by quality reactions of the purine fraction with aromatic amines and phenols as well as by the values of Rf and UV spectrum of individual compounds examined by paper chromatography of the purine fraction.