For the first time, sleep was studied in a representative of the order of Sirenia. Slow wave sleep occupied 27%, and paradoxical sleep 1% of the total recording time in the Amazonian manatee. Trichechus inunguis. The circadian rhythmicity of sleep was pronounced. During the sleep period, the manatee woke up for a short time for each respiratory act. Interhemispheric asynchrony of the electrocortical slow wave activity was found.

We present the results of an experimental study of the structure of the radio-wave refractivity and its dynamics by a network of seven ground-based GPS and GLONASS receivers in Kazan, Russia. It is shown that the remote sensing results agree well with the data of weather stations, radio sounding, and reanalysis. The standard deviation of the refractivity value, which are obtained using the sensing results from the radio sounding data amounts to 2% of the average value at altitudes of up to 500 m. It is found that the refractivity structure has overnight variations, as well as and mesoscale spatial and temporal variability.

No abstract