[EXPERIMENTAL AND THEORETICAL STUDIES OF HUMAN HYPERCAPNIC VENTILATORY RESPONSE WITH THE USE OF MATHEMATICAL GAS EXCHANGE MODELING].

A mathematical model of biotechnical system integrating the human cardiorespiratory system with hard- and software was designed to investigate breathing control. The model describes dynamics of carbon dioxide and oxygen in 3 biotechnical system compartments in the course of rebreathing tests. The tests do not require tanks with compressed gas and, therefore, can be performed in space flights.

[Dynamics of duration of tracheal forced expiratory noises during long-term isolation in the "Mars-500" experiment].

Dynamics of duration of tracheal forced expiratory noises in a group of volunteers was studied before, during and after 520-days confinement. The duration did not change in most volunteers. Two volunteers demonstrated significant changes of tracheal sounds duration and some spirometric parameters.

[Estimation of the forced expiration tracheal sounds intensity].

The investigation of tracheal sounds of forced expiration is realized on the basis of the mathematical model of forced expiration. It is demonstrated that a separation flow in the region of a dynamical contraction trachea during forced expiration may to cause tracheal sounds generation.