Experimental study of the mutagenic activity of gentamicin sulfate in relation to the causative agent of plague

Gentamicin sulfate was studied with an aim of obtaining mutants of the plague microbe with a changed character of requirements in the growth factors. The antibiotic provided a high yield of auxotrophic mutants and induced streptomycin resistance in some cells. Mutants with single dependence on arginine, leucine, histidine and uracyl were most often. Comparison of the data obtained with gentamicin and those obtained with other chemical mutagens showed that gentamicin by its mutagenic activity was only slightly inferior than the preparations of the group of supermutagens.     

Extinction coefficient of thyroglobulin

The extinction coefficient at 280 nm of the solution (pH 7,2-7,4) of thyroglobulin from normal thyroid and nodular euthyroid goiter was measured with the values of 0,6-0,7 to 0,9 ml.mg-1.cm-1. The value of E1%280 as function of the iodoamino acid content depends on the morphological state of the thyroid gland. A simple method for determination of the E1%280 value by measuring of the protein absorption spectrum is proposed.     

Delayed hypersensitivity in the chronic cholera vibrio carrier state in animals with an absence of normal microflora

The development of allergy in germ-free rats in chronic vibriocarriership was studied. The formation of specific delayed type hypersensitivity was found to occur to a limited extent in the animals devoid of normal microflora. The picture of hyperergic inflammation was revealed in the lymph nodes of vibriocarrier rats, the test for specific allergen being positive.     

Trends in the ignition and combustion of zirconium

Combustion, Explosion, and Shock Waves -     

Non-isothermal Kinetics of Benzo[a]Pyrene Photooxidation in Glyceryl Trioctanoate

Benzo[a]pyrene (BaP) was dissolved in glyceryl trioctanoate, heated in a glass reaction vessel within temperature range 297.95–361.85 K with heating rate of 1 K/min and simultaneously exposed to UV light at wavelength λ = 365 nm at radiation power 20 mW cm^?2 in order to study the decrease of BaP concentration due to its photooxidation. The concentration of BaP was determined by HPLC-FD periodically in 5 min intervals. As observed, the BaP concentration decreased from 62.2 μg L^-1 to 19.8 μg L^-1. From the experimental results, the parameters characterizing the non-isothermal kinetics of BaP photooxidation have been obtained. The parameters were tested at two various isothermal conditions (290.16 and 323.26 K) to verify a suitability of derived parameters. Comparing calculated and measured data of half-lives of BaP decrease at mentioned temperatures it was found that calculated half-lives are in a good accordance with those experimentally obtained values, when relative standard deviations at 290.16 K were 17.0% and 5.4% at 323.26 K, respectively. The kinetic parameters enable the calculation of the rate constant for any temperature in isothermal regime and make possible to model, in general, the kinetics of such processes without a deeper insight into their mechanisms.