Systems and methods for adjusting threshold voltage. More particularly the submucosa is enzymatically digested and gelled to form a shape retaining gel matrix suitable for inducing cell proliferation and growth both in vivo and in vitro. Direct visual verification of the sinuses and their natural ostia is utilized. A frame dividing section 23 divides the generated frame, by a predetermined number, into a plurality of divided frames. If the bullet assembly is in the passage, the pin also projects into a groove of the bullet assembly, thereby, locking the bullet assembly within the passage and causing the hinge rolling assembly, which is pivotally connected to the door to move via operation of the powered pulley system. Processes for reconstructing and calibrating image information on a recording medium are also provided.