Application of the correlation integral to respiratory data of infants during REM sleep.

Non-linear time sequence analysis has been performed on infant sleep measurement data in order to obtain more information about the respiratory processes. As a first step, respiration data during REM sleep were analysed with methods from non-linear dynamics, especially, the correlation integral and the slope of its log-log plot, representing the correlation dimension. Before calculation of the correlation integral, a special kind of filtering has to be applied to the data.

Persistent age-distributions for a pair-formation model.

Conditions on the vital rates of a two-sex population are presented which imply the existence or nonexistence of exponentially growing persistent age-distributions.