This invention discloses a novel method for the conversion of carboxylic acids to carbothioic acids and application of the method to the preparation of androstane carbothiolates, such as fluticasone propionate, which avoids column chromatography. One approach includes directly determining a state of vasoconstriction or vasodilation in a portion of a body, and supplying heat to the portion of the body when vasoconstriction is determined, and removing heat from the portion of the body when vasodilation is determined. Thus, a molded foam resin and a speaker diaphragm according to the present invention can be thinned, designed with different tone of color on surfaces thereof and lightened without deteriorating stiffness thereof. Each fixture includes a post inserted into the corresponding hole of the fan, a pressing portion pressing the fan toward the heat sink and a locking leg interlocking with outmost fins. The synthetic population includes a plurality of synthetic entities.