Effect of a small C3O2 additive on the vibrational distribution function of CO molecules in a low-temperature plasma

The concentration of carbon suboxide (C₃O₂) in the plasmas of sealed-off discharges in mixtures of CO with noble gases is measured for the first time by mass-spectroscopic technique. It is shown that the production of C₃O₂ (and, possibly, more complex carbon oxides) in a gas-discharge plasma significantly boosts the vibrational relaxation of CO molecules and thus greatly affects their vibrational populations. Adding xenon to a He: CO mixture reduces the concentration of C₃O₂. The effect of pulsed UV radiation on the vibrational populations of CO molecules is studied experimentally. It is shown that UV irradiation of the gas mixture after long-term discharge operation increases vibrational populations in the plateau region up to the values observed at the beginning of the discharge. This effect is attributed to the decay of C₃O₂ molecules under the action of UV radiation.     

The EEG indices of the functional status of the operator in prolonged monotonous work at a computer]

The EEG data obtained in 4-hour experiments with simulation of monotonous performance at a computer display were analyzed. A certain difference in the dynamics of the functional state was revealed between the groups of subjects which differed in their background level of cortical activation. Practically the same performance efficiency in these groups was supported by different mechanisms: via self-regulation mechanisms in the subjects with a high initial level of cortical activity and by involvement of "self-correction" realized through activation of nonspecific subcortical brain structures. The development of the excessive stress in the second group of subjects expressed in an increase of theta rhythm power density indicated the higher "physiological cost" of monotonous operator's work for persons with low level of background cortical activation.     

Modifying action of Mn(II) chelate with ethyl ester of salicylydene tyrosine on some biophysical parameters of erythrocyte membranes of the irradiated organism

The presentation summarizes the results of studies on radioprotective activity of newly synthesized Mn(II) chelate with ethyl ester of salicylydene D,L-tyrosine, basing on the evaluation of its membrane-protective effects, revealed at different periods post the exposure of the organism to ionizing radiation. It was revealed that the administration of the compound into the animal organism before the radiation exposure (gamma-irradiation of 60Co at a dose level of 4.8 Gy) produced correcting action on structure-functional properties of erythrocyte membrane of irradiated rats: the excessive activation of lipid peroxidation of erythrocyte membranes was inhibited, the passive permeability of erythrocytes for K+ ions was normalized, the deformity and membrane potential of erythrocytes according to hydrogen-chlorine gradient were recovered.     

Magnetic fields alter electrical properties of solutions and their physiological effects

Calcium chloride and snail physiological salt solutions were exposed to static magnetic fields (2.3–350 mT), and the physical properties of the solutions as well as their biologic effects were studied. Our preliminary observations show that these fields alter physicochemical properties of CaCl₂ solutions and the functional effects of physiological solutions. Experiments on CaCl₂ solutions demonstrated field-dependent changes of electrical conductivity, with the magnitude and the direction of conductivity change being a function of both concentration and field intensity. The changes in conductivity were maintained for periods in excess of 1 h after exposure. Conductivity changes were not found after exposure of physiological solutions to static magnetic fields, but changes of biological consequence did occur. Other experiments showed that there were several changes in cellular function observed in ganglia and isolated neurons of Helix pomatia when the perfusing medium was changed from the normal physiologic solution to the same solution after exposure to magnetic fields. These changes include membrane depolarization and increased action potential discharge, reduced uptake of Ca into cells, altered content of cyclic nucleotides in ganglia, and increased volume of isolated cell bodies. A change in hydration of calcium ions may be one of the consequences of magnetic-field exposure, and in physiological solutions this change may have functional consequences. © 1994 Wiley-Liss, Inc.     

Effects of spatial-imagery task performance on the heart rate variability

Effects of the efficiency of spatial task performance on the autonomic heart control were studied. Dynamic changes in autonomic balance diagnosed on the heart rate variability during maze-model task performance (the type of spatial-imagery activity) showed that the type of heart rate regulation depended on the performance efficiency. The results suggest that in subjects with low performance efficiency, problems in performance are associated with negative emotions that produce the emotional psychogenic stress. In subjects with high efficiency, the autonomic contour of the heart rate regulation prevailed. This was presumable associated with the adequacy of the maze-model task.     

A drop in "apparent" blood viscosity due to administration of high-molecular polymer capable of augmenting viscosity

Influence of a high-molecular compound capable of augmenting viscosity, namely: polyethylene oxide Polyox WSR-301, on hemodynamic parameters in rat mesenteric microvessels was investigated. A substantial decrease in the arteriolar hemodynamic resistance caused by the polymer was revealed. Special research has shown that this reaction is not connected with a vasodilatation and, therefore, is caused by a reduction in the "apparent" viscosity of the blood, i.e., it is a consequence of changed properties of the blood flow.     

Functional state of the autonomic nervous system according to the data of heart activity during performance of a computerized visual-spatial task

The influence of the performance of a computerized visio-spatial task on the state of the autonomic nervous system of PC operators was studied. Statistical characteristics of the operator's heart rhythm during the 3-hour period of work on a computer were analyzed using Baevsky's method of variational pulsometry. The operators were classified in three groups by the character of their reaction to loading. It was suggested that the visio-spatial task performance on a computer could act as a stress factor only on a certain category of people.