tailieunhanh - Báo cáo hóa học: " Review Article Multimodal Pressure-Flow Analysis: Application of Hilbert Huang Transform in Cerebral Blood Flow Regulation"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Review Article Multimodal Pressure-Flow Analysis: Application of Hilbert Huang Transform in Cerebral Blood Flow Regulation | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2008 Article ID 785243 15 pages doi 2008 785243 Review Article Multimodal Pressure-Flow Analysis Application of Hilbert Huang Transform in Cerebral Blood Flow Regulation Men-Tzung Lo 1 2 3 Kun Hu 1 Yanhui Liu 4 . Peng 2 and Vera Novak1 1 Division of Gerontology Beth Israel Deaconess Medical Center Harvard Medical School Boston MA 02115 USA 2 Division of Interdisciplinary Medicine Biotechnology and Margret . Rey Institute for Nonlinear Dynamics in Medicine Beth Israel Deaconess Medical Center Harvard Medical School Boston MA 02115 USA 3 Research Center for Adaptive Data Analysis National Central University Chungli 32054 Taiwan 4DynaDx Corporation Mountain View CA 94041 USA Correspondence should be addressed to Vera Novak vnovak@ Received 3 September 2007 Revised 15 February 2008 Accepted 14 April 2008 Recommended by Daniel Bentil Quantification of nonlinear interactions between two nonstationary signals presents a computational challenge in different research fields especially for assessments of physiological systems. Traditional approaches that are based on theories of stationary signals cannot resolve nonstationarity-related issues and thus cannot reliably assess nonlinear interactions in physiological systems. In this review we discuss a new technique called multimodal pressure flow MMPF method that utilizes Hilbert-Huang transformation to quantify interaction between nonstationary cerebral blood flow velocity BFV and blood pressure BP for the assessment of dynamic cerebral autoregulation CA . CA is an important mechanism responsible for controlling cerebral blood flow in responses to fluctuations in systemic BP within a few heart-beats. The MMPF analysis decomposes BP and BFV signals into multiple empirical modes adaptively so that the fluctuations caused by a specific physiologic process can be represented in a corresponding empirical mode. .