Figure 5: Representative optical fluorescence microscopy images of hABMSCs cultured for 5 days in static conditions (a1–d1) or at 10 min/day (a2–d2), 30 min/day (a3–d3), 60 min/day (a4–d4), 120 min/day (a5–d5), and 180 min/day (a6–d6) by OSS without OM; cell nuclei (a1–a6), actin filaments (b1–b6), OCN (c1–c6), and merged images (d1–d6) of the fluorescence stains. Fluorescence images showed more intense observation in OSS groups without OM compared to those of control.