It is an object of the present invention to obtain a highly pure alcohol by reducing the aldehyde concentration in the product alcohol efficiently and inexpensively. The light source unit has an installation mechanism for installation to the base plate, and the base plate has an installation mechanism counterpart engaged with the installation mechanism. In one procedure, a shape or profile of a curve of a second-order moment of hydrophobicity is determined. The invention provides, among other things, a smooth, controllable engagement of the centrifugal clutch. There is a washing step between alternate layers of the therapeutic agent and cationic polyelectrolyte carrier, so that the amount of the therapeutic agent on the insertable medical device represents the portion that is stably entrapped and adsorbed on to the medical device. The open wells contain regions which are substantially rough or textured and regions which are substantially smooth.