Growth of Stylaria lacustris (L.) (Oligochaeta,Naididae)

The peculiarities of the growth in weight and length of Stylaria lacustris (L.) on the basis of observations in experimental vessels are considered. The growth of this species fits a parabolic curve. The equations relating weight to absolute growth rate as well as weight to duration of life are given.     

Kinetics of Candida lipolytica yeast growth and biosynthesis of alpha-keto acids with thiamine deficiency in media with different carbon sources

The growth kinetics of Candida lipolytica on glucose, acetate and hexadecane was studied in batch cultures at thiamine deficiency. The growth at the deceleration phase is of a linear character. The transition from the exponential phase to the linear one is accompanied with the accumulation of alpha-keto acids in the cultural broth, which is also observed in the stationary phase. The rate of acid production in the linear phase increases as the specific growth rate decreases, and reaches the maximum value in media with different carbon sources at mu = 0.01--0.06 h-1. Apparently, the deceleration of growth is due to a decrease in the activity of a thiamine-dependent enzyme (pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase or transketolase) which is a limiting point of biosynthetic processes. Here, a linear growth is determined by the constant activity of this enzyme per unit volume of the cultural broth which, in turn, depends on the constant concentration of the coenzyme, thiamine diphosphate, in the same volume.     

Synthesis of octapeptides containing fragments of lac-repressor primary structure

Four octapeptides containing the dipeptide fragments of the lac-repressor primary structure have been synthesized. The general scheme of synthesis consisted in the preparation of tetrapeptides using successive elongation from the C-terminus by the mixed anhydride method followed by their condensation into octapeptides.     

Optimal control of the microflora environment in suppurative foci

The informative capacity of various statistic parameters characterizing the ecology of pathogens of purulent processes was studied. Many-years' results of the routine bacteriological tests of the materials from purulent wounds in patients from surgical, traumatological and burn departments served as the study subjects. The frequency, persistence and contamination capacity of the pathogens were investigated. Data on the changes in the frequency parameter with respect to the main pathogens of wound infections in various contingents of patients were collected. In relation to the observation period and contingent of the patients, various microorganisms were found to be permanent, supplementary and casual. The use of the ecological parameters was shown to provide integrated information on the etiological role of the pathogens in the development of purulent processes. The information characterized the microbial properties which should be considered in planning the use of antibacterial drugs and estimating the efficacy of the epidemiological control.     

Defining parameters of the model of single autosomal two-allele locus with incomplete penetrance differing in the two sexes

A variant of the model of single autosomal two-allele locus with incomplete and different for both sexes penetrance is under consideration. The variant may be used for revealing the effect of the major gene for determination of multifactorial disease encountered with different frequencies in men and women. Some approaches to obtaining the values of 7 parameters of the model under consideration are regarded on the basis of usually available data on probands' relatives.     

Equations for segregation frequencies determined by Weinberg's generalized method in a model of a single autosomal 2-allelic locus with incomplete penetrance

Equations are proposed for segregation frequencies determined by generalized Weinberg's method (SFw). The equations give an expression for SFw in terms of basic parameters of a single autosomal two-allele locus model with incomplete penetrance (SAL-2 model), namely, in terms of the frequency of one of the alleles and the penetrances of three genotypes (p, II2, II1, II0). The equations proposed are intended to be included into the system of equations to find the basic parameters of the SAL-2 model.