[Dependence of the activity of L-amino acid oxidase in the fungus Aspergillus niger R-3 on the source of nitrogen in growth media].

Various populations of peroxisomes in cells of Aspergillus niger R-3 were formed under the growth in media containing 0.5% glucose and various sources of nitrogen (1/4 of optimal concentrations of (NH4)2SO4, L-alanine, and L-methionine). Different levels of of L-amino acid oxidase activity were found in these populations of peroxisomes.

[Electrophysiologic study of the connections of the 2d somatosensory area of the cortex with the neo-, paleocortical and striate formations of the brain].

2nd somatosensory area (C2) was shown to have modulating influence on evoked activity of the 1st somatosensory and visual areas. Electrical stimulation of C2 evoked short latency potentials in the structures of paleocortex (hippocampus) and striatum (putamen, caudate nucleus). Analysis of the data obtained here and elsewhere (19) suggests the important role of C2 in mechanisms of selection, comparison and integration of adequate sensory information under conditions of uncertainty, for the programming of behaviour.

[Comparative assessment of the role of the primary and secondary somatosensory regions of the cerebral cortex during conditioned reflex behavior in animals].

The first (SI) and second (SII) somatosensory cortical areas were ablated in one group of cats after preliminary learning of tactile differentiation of rough and smooth surfaces of the floor coating in a special chamber. Somatosensory areas were ablated in another group after learning an adequate choice of the reinforcement side in response to a bell and a metronome. Unilateral and bilateral ablation of SI affected but little the elaboration and achievement of the above acts.

[Determination of the sensitivity of head lice to insecticides].

The author recommends a method of determination of sensitivity of head lice which, in difference from the accepted one, is based on the establishment of the time interval between the death of 50-100% of the insects as a result of the contact with the insecticide in definite doses of the active substance. The method permits to assess the rapidity and the extent of the toxic action of various substances on lice; it is simple and convenient for use in practice.