Biomedical subjects
Publications and source records attributed to A A Arzamastsev.
The available models of the microorganism growth kinetics are analyzed. The possibility of application of the Monod model is studied. It is shown that these models do not permit describing adequately the experimental data at different initial concentrations of biomass and substrate that vary in a wide range. The calculations of the static modes of operation of biochemical react ors differ greatly.
A simple mathematical model for the dynamics of biocenosis in an open system was worked out. The model is based on the finite-difference presentation of experimental data. It also takes into account the past history of population development. The testing of the model proved its ability to forecast the density of populations in open systems.
The autostabilization of the environment pH value in batch cultures of yeast Candida tropicalis was experimentally investigated. The pH alternation had unidirectional compensatory nature, which allowed to represent the reaction of the system as the reaction of hypothetical linear object with negative feed-back. The transmission functions of structural elements of this object were determined. It was shown that such a model describes experimental data quite well in a wide range of initial environment pH values.
Ranges within which the pH of the environment can be self-regulated have been determined for microorganisms belonging to the Pseudomonas genus. The ability of these microorganisms to self-regulate the pH was detected both at an increase and a decrease in the pH of the environment as compared to its optimal value. The rate of self-regulation appears to be proportional to the concentration of viable cells in a suspension. The results may be used for creating an economical system for maintaining the pH of the environment in industrial fermentation.
A method is proposed for determining the rate of endogenous respiration in Pseudomonas cells grown under the conditions of batch cultivation. The method takes into account the dynamic characteristics of the gauge and of the secondary instrument. The rate of Pseudomonas endogenous respiration was shown to be at the beginning of the range established earlier for other bacteria.
The answer to this question is not yet known. There are two ways to express information, i.e., to reduce the number of letters in alphabet (n), which simplifies the decoding machine, but leads to longer informational sequences, or to increase n, which shortens sequences, but complicates the informational machine. The compromise between these two possibilities would be to obtain the minimum of one of summary informational component's parameters. The summary component is the sum of corresponding decoding machine's and the program's parameters. In this work it was demonstrated that DNA four-letter code is optimal, for it allows the minimal volume of summary cell informational contents. But it is so only for the most simple DNA. Our calculations may indirectly show that such DNA (and not more complicated) was the object of "projecting" at one of the biological evolution's early stages.
It is shown that the four-letter code of the messenger DNA sequences is optimal in the sense that it provides minimal volume of the total information < < stuffing > > of the cell. The optimal code holds true only for the simplest DNA. This fact is indirect evidence that these very DNAs were the object of < < construction > > at earlier stages of biological evolution.