Abstract: Methods and applications of a lyophilized tissue matrix derived powder (TH Powder) are disclosed. The methods include improved approaches to viral and bacterial control, improved multi-stage grinding techniques and use of improved grinding systems. The TH powder produced using the disclosed methods includes properties, such as small powder particle sizes, nearly instant rehydration time, high solubility, flowability and injectability, and optionally short (˜3-5 minute) polymerization time duration, that enable or improve important clinical applications. A variety of clinical applications are disclosed, including, for example, some that take advantage of the TH Powder's effectiveness in optimizing wound healing, providing a 3D scaffold onto the wound site, improving cells regeneration and proliferation, providing a temporary coverage to avoid irritations, anti-fibrosis, anti-adhesion and anti-inflammation, The TH powder is optionally sterilized while maintaining biological components.

Abstract: A tracking servo method of an optical video disc player and its special device which accomplish angle adjustment in a simple, time-saving and effort-saving manner and improve the tracking servo capability of the optical video disc player. In the tracking servo method of an optical video disc player, a laser beam is split into a main beam and two sub beams, and tracking error signal generated from the two sub beams are subtracted from tracking error signal generated by the main beam; light spot of the main beam is circular in shape, and light spots of the two sub beams are elliptical in shape. The special device has an effective grating region (1). The effective grating region (1) has a middle zone (2) and two side zones (3, 4); the middle zone (2) has two side edges which are parallel and equal in length, and the two side edges has a distance therebetween which is 10-90% of diameter of the effective grating region (1), and the middle zone (2) and the two side zones (3, 4) have different grating pitches.