APPLICATION OF WAVELET TRANSFORM TO ANALYSIS OF HUMAN SKIN BLOOD FLUX SIGNAL

摘要

The traditional parameters to evaluate humanmicrocirculation such as mean values of skin blood flux(SBF) and velocity of skin blood flow measured by laserDoppler flowmetry (LDF) failed to find the biologicaleffects of magnetic field (MF) on human microcirculationaccording to numerous researches. Although thisinefficacy of MF indicated by these traditional parameters,other potential parameters were seldom investigated.Therefore, this study aimed to find other potentialparameters by using time-frequency analysis as indicatorsto investigate whether MF affects human microcirculationin future studies. Continuous wavelet transform which hassuperior frequency resolution in low frequency band wasapplied in present study to convert two dimensional dataof flux signal with low frequency band into threedimensional data involving the temporal and frequencyinformation of the original signal. Six characteristic peaksidentified relating to microvascular mechanism wererecognized in the frequency interval between 0.005 and 2Hz and the amplitude of each peak varied with time. Thismethod may provide a new idea and method for theanalysis and processing human SBF signal and lay afoundation for future study of MF effects on humanmicrocirculation. However, more studies are needed todemonstrate the interesting and encouraging effects of MFon untraditional parameters such as wavelet coefficientsof SBF signal and to explain the precise actionmechanism of MF on human microcirculation.