The arrangement of a store room for residential buildings comprising stacked apartments is presented. The invention encompasses methods for mutating cells using a combination of mutagens, particularly wherein at least one mutagen is an insertional mutagen, to achieve homozygous gene mutation or mutation of multiple genes required cumulatively to achieve a phenotype to create knock-outs, knock-downs, and other modifications in the same cell. The nanostructure may be formed in a ring shape, and the metal layer may include a plurality of metal layers formed of different metals. The inner container may also allow product therein to be visible from outside the package as well.