There are no regular patterns in the fluctuations of the content of gonadoliberin in relation to the time of day in the preoptic region and the median eminence in females and males. However, the existence of a well-marked circadian rhythm of the fluctuations of this neurohormone has been identified in females in the vascular organ of the lamina terminalis. Its level is extremely low in the morning; its level increases five-fold immediately after noon, and ten-fold at 1700–1800 h. This rhythm does not depend on the stage of the estrous cycle and is manifested identically both in diestrus and in proestrus. Circadian fluctuations in the content of gonadoliberin in the vascular organ of the lamina terminalis were not observed in males. The chronic exposure to various xenobiotics in low concentrations (toloul, benzol, dioxan, styrol, and lead) leads to a break in the circadian rhythm of the gonadoliberin content in the vascular organ of the lamina terminalis in females; this is expressed first and foremost in a significant increase in the level of this neurohormone in the morning hours. This is apparently associated with attenuation of inhibitory tone; this is indirectly confirmed by a simultaneous increase in the level of prolactin in the blood.

Cooling with crystallization at high rates makes it possible to obtain a homogeneous highly dispersed dendritic structure in an alloy of the Al−Mg−Li−Zr system.

The sintered alloy 1201 is characterized by more uniform and more disperse structure than the alloy obtained from ingots.

Pressed bars of alloy SAP with slaty fractures have lower strength characteristics than similar bars with fine-grained fractures.

The strength characteristics of SAP-1 plate are affected not only by the distance between oxide particles but also by the block size of the matrix.