title: Phase shifts of synchronized oscillators and the systolic-diastolic blood pressure relation.
abstract: We study the phase-synchronization properties of systolic and diastolic arterial pressure in healthy subjects. We find that delays in the oscillatory components of the time series depend on the frequency bands that are considered, in particular we find a change of sign in the phase shift going from the very low frequency band to the high frequency band. This behavior should reflect a collective behavior of a system of nonlinear interacting elementary oscillators. We prove that some models describing such systems, e.g., the Winfree and the Kuramoto models, offer a clue to this phenomenon. For these theoretical models there is a linear relationship between phase shifts and the difference of natural frequencies of oscillators and a change of sign in the phase shift naturally emerges.
authors.affiliation: TIRES-Center of Innovative Technologies for Signal Detection and Processing, Università di Bari, Bari, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Angelini
authors.forename: G
authors.initials: G
authors.lastname: Lattanzi
authors.forename: R
authors.initials: R
authors.lastname: Maestri
authors.forename: D
authors.initials: D
authors.lastname: Marinazzo
authors.forename: G
authors.initials: G
authors.lastname: Nardulli
authors.forename: L
authors.initials: L
authors.lastname: Nitti
authors.forename: M
authors.initials: M
authors.lastname: Pellicoro
authors.forename: G D
authors.initials: GD
authors.lastname: Pinna
authors.forename: S
authors.initials: S
authors.lastname: Stramaglia
mesh_terms: D001683:Biological Clocks / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D003198:Computer Simulation; D003971:Diastole / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D008955:Models, Cardiovascular; D010507:Periodicity; D011673:Pulsatile Flow / Q000502:physiology*; D013599:Systole / Q000502:physiology*