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Meeting Abstract
A key process in the development of closed circulatory vasculature is flow produced by the heart, which often begins as open circulatory flow. However, flow in open circulatory systems and microvasculature is often difficult to quantify. In the past, the movements of blood cells have been used as a proxy for fluid speed inside small vessels, but recent works have demonstrated that blood-cell speeds result in underestimating flow by up to 50%. In this study, we used micro particle image velocimetry (micro PIV) and particle tracking velocimetry (PTV) to quantify fluid flow speeds in the circulatory system of the tunicate, Ciona savignyi. Micro PIV is a technique that uses computational algorithms to reconstruct fluid flow velocity fields based on the bulk movement of illuminated tracer particles, and PTV tracks individual particles and reconstructs velocities from their displacements. We present a comparison between two artificial tracer particles (fluorescent microspheres and fluorescent liposomes) introduced by injection and two flow reconstruction techniques with the movements of blood cells at four points within the circulatory system, including the heart.