Apparatus for storing items within vehicle compartments that can be manipulated into an operative position and a closed position with a single hand are provided. The assist device includes a detecting portion and an assist device driving portion. The purified hydroxycarboxylic acid is further polycondensed to provide a hydroxycarboxylic acid oligomer, which is de-polymerized to provide a cyclic ester comprising a dimer of the hydroxycarboxylic acid, and the cyclic ester is converted into a polyhydroxycarboxylic acid by ring-opening polymerization thereof. The variable resistive layer has a sidewall that is separated from an inner side surface of the opening to define a gap between the sidewall of the variable resistive layer and the inner side surface of the opening.