Provided are a system and a method for providing contents using an open API. The light source is adapted for providing an elliptical light beam defining different diverging angles in different directions, wherein any cross-section of the elliptical light beam emitted from the light source defines a long axis and a short axis which are perpendicular to each other. A retaining fixture secures ends of the at least one cleaning belt in a fixed position relative to the insertion receiver. A reading signal for detecting the resistance value of the recording layer in the variable resistance element is applied with a polarity of one of the threshold values of the applied signals which one has a higher absolute value and with a value lower than the absolute value. The leading edges of the stationary vanes are shaped to direct any stringy material into the radial gaps between the free ends of the stationary vanes and the rotating nose cone to be shredded and thus prevent fouling and clogging of the pump assembly when such stringy material is generated during the polymerization process.