L-pyroglutamyl-D-alanine amide normalizes the function of the developing brain damaged by antenatal alcoholization in rats

The effects of the synthetic dipeptide, L-pyroglutamyl-D-alaninamide (LPDA) were studied in the experiments on offspring of alcoholized during the pregnancy (5 g/kg/day) females. This dipeptide, which revealed the nootropic activity in previous experiments, was injected to the pups in dose of 1 mg/kg from 8 to 19 days of life. LPDA was shown to prevent the delayed disturbances of learning in passive avoidance test, of extrapolatory behaviour in escape test, to attenuate the emotional hyperreactivity. LPDA normalized EEG power spectrum, decreased interhemispheric asymmetry. This substance attenuated the disbalance evoked by prenatal alcoholization.     

Limiting Parameters of the Plasma Opening Switch

Implementing programs for nuclear fusion research and X-ray generation requires the creation of superpower generators based on plasma opening switches (POSs) capable of commutating currents as high as several tens of megaamperes at output voltages of up to 5 MV and higher. The physical mechanisms limiting the POS voltage are investigated. It is shown that, as the generator voltage U _g increases, the voltage multiplication factor k = U_POS/U_g (where U_POS is the POS voltage) decreases. An explanation for such a dependence is proposed, and the maximum value of the POS voltage is estimated. A POS design that enables operating in the above current and voltage ranges is considered. The design is based on applying an external magnetic field to the POS interelectrode gap, increasing the initial generator voltage, and decreasing the linear (along the perimeter of the outer electrode) density of the charge passing through the POS during the conduction phase.     

Hereditary effects of artificial selection of sperm for the endurance trait in the carp Cyprinus carpio and the frog Rana temporaria

Studies have been made of the effect of artificial selection of parental sperm by maximum motility time (maximum tolerance) on the body length in carp larva and heat resistance level of muscle tissue in tadpoles. Sperm selection increases mean values of these parameters due to the increase in the progeny of the relative number of long-sized individuals and individuals with higher heat resistance of muscle fibers.     

The effective dosage as the stimulating exposure in fractionated gamma irradiation

The study of early neurological disturbances (END) in rats after fractionated gamma irradiation with doses of 37.5-225 Gy at dose rate of 30.11 Gy/min has demonstrated that the initial response of animals to pulse ionizing radiation is a function of the electric charge induced by ionizing radiation. A change in the probability of occurrence of each of the END symptoms, with the increased intervals between exposures, is merely an indirect indication of the eliminating mechanisms and is intricately connected with the irritating charge value. The period of dose half-elimination in 16 min. The threshold effective dose rate leading to END is of the order of 2.12 Gy/min. The proposed empiric relationships permit to correlate the probability of END symptom occurrence with the continuous quantitative parameter of fractionated irradiation, that is, with an effective dose as an analogue of the irritating effect.