Abstract: A method for forming a cardiovascular structure in culture is provided. The method includes applying mechanical force to a cell population in culture such that a cardiovascular structure is formed. In some embodiments, the mechanical force is produced in culture medium by a pulsatile liquid flow with a retrograde component. The cell population can include stem cells or differentiated cells, or combinations of both. In particular embodiments, a cardiovascular valve is formed. Scaffolds for the support and growth of the cell population, and bioreactors including the scaffolds, are also provided.

Abstract: A multilayered impedance pump is formed by an inner tube and an outer tube which have different mechanical characteristics. The outer tube is relatively stiff, and can be used for a structural material. The inner tube is excitable, and a gel is placed between the inner and outer tube. The actuator actuates the gel to cause pressure waves along the inner tube.