In one embodiment of the invention, a memory apparatus is disclosed. The adjustable rack system may be used to vertically stack and display or store pies or other food or non-food items. In this way, it is possible to protect the slide-contact surface of the magnetic head from eccentric wear and avoid deterioration of the magnetic head performance. The tape is cut to the desired width for the chink that is to be sealed and is finished in a rolled configuration. Along their path of travel, the structures pass a transmitter that emits transfection energy sufficient to cause the exogenous species in the suspension to permeate the structure membranes and enter the interiors of the structures.