A stackable container includes top and bottom surfaces; opposing side surfaces; opposing end surfaces; and interlock mechanisms on at least one of 1) the top and bottom surfaces, 2) the opposing side surfaces and 3) the opposing end surfaces. Methods for recognizing and using the RDS data to activate or initiate applications on the handheld device enable a wide range of uses and new services. Gradation correction is performed on the input image such that appropriate hue and saturation are achieved while emphasizing a main object. In addition, methods for storing andor transplantation of porcine neural cells are described. The preferred gel formers are acrylic acid polymers, xanthan gum and hydroxyalkylcellulose compounds.