1. Wavelet Analysis of Skin Blood Oscillations in Persons With Spinal Cord Injury and Able-Bodied Subjects 
Zengyong Li, PhD, Jonathan Y. Leung, MSc, Eric W. Tam, PhD, Arthur F. Mak, PhD 
Archives of Physical Medicine and Rehabilitation 
Volume 87, Issue 9, Pages (September 2006)
DOI: /j.apmr
Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

2. Fig 1
Schematic of experimental posture and setup. The testing posture was lying with both hips flexed to 90°. External pressure was applied to the skin by a pneumatic indentor (diameter, 25mm) aligned perpendicular to the skin over ischial tuberosity (IT). Both legs were supported by a height adjustable platform.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

3. Fig 2
The wavelet transform in (A) time-frequency plane and (B) averaged spectrum of LDF signal shown on a log scale. The vertical lines indicate the outer limits of frequency interval: (1) .01 to .02Hz, (2) .02 to .06Hz, (3) .06 to .15Hz, (4) .15 to 0.4Hz, and (5) 0.4 to 2Hz, which correspond to endothelial related metabolic, neurogenic, myogenic, respiratory and cardiac activities, respectively.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

4. Fig 3
Normalized absolute and relative amplitudes for the 5 frequency intervals for the resting skin over the ischial tuberosity in (A, B) the able-bodied subjects and (C, D) persons with SCI during the preloading and the 2 postloading periods (t1, t2). Significant differences are marked between postloading (t1) and preloading with *P<.05 and †P<.01; postloading (t2) and postloading (t1) with ‡P<.05 and §P<.01. Each value was calculated as a percentage of each PRE value in the same group.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

5. Fig 4
Relative amplitude for the 5 frequency intervals for the resting skin over the ischial tuberosity in the able-bodied subjects and persons with SCI during the (A) preloading and (B) postloading periods (t1). *Significant differences are marked between persons with SCI and able-bodied subjects (P<.05).
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

6. Fig 5
Typical examples of time-averaged wavelet transform calculated from signals measured in the resting skin over the ischial tuberosity in (A) an able-bodied subject and (B) a person with SCI. The vertical lines indicate the outer limits of each frequency interval from 1 to 5, which correspond to endothelial related metabolic, neurogenic, myogenic, heart, and respiratory activities, respectively.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions