Ultrasound DopplerHigh Resolution Flow CytometryCell Culture FacilitiesVenous Function Philips Epiqs 5 Doppler Ultrasound with vascular and cardiac probes for measuring artery function, stiffness, cardiac mechanics, microvascular Beckman-Coulter high resolution flow cytometer to identify rare cells (e.g. progenitor), microvesicles from bodily fluids Dedicated Biological Safety Cabinet for human cell culture and tissue culture. Microscopy, ultracentrifuge, CO2 incubators Venous occlusion plethysmography system for measuring lower limb venous capacity, stiffness and regurgitationTypical venous compliance curvesParticipant set-up