Figure 7: Line profiles taken by EDX across the reserve zone-epiphysis/subchondral bone (RZ-EP/SB) interface for (a) 20-, (b) 35-, and (c) 480-day-old pigs. Vertical red dash lines denote the transition zone between cartilage and bone. The transition zone is determined based on the backscatter image and the EDX line profiles of maximum and minimum values of major elements (Ca, P, and C). (d), (e), and (f) are the smoothed data of (a), (b), and (c), respectively, using a Gaussian filter. CPS = count per second.