Aspects of the present invention relate to methods and systems for presenting digital content in a field of view of a head-worn computer. In particular, the present invention provides formulations of at least one unsaturated phospholipid and an amphipathic or hydrophobic pyrimidine drug, methods of making these formulations and the use of such formulations in a variety of contexts, including, for example, the treatment of proliferative disorders, such as tumors and cancers. The compositions contain salts of one or more preservative metals and carboxylic acids having one or a plurality of hydroxyl groups rendered soluble by means of complex formation with boric acid or a water soluble salt thereof. The composite elastic material covered with an elasticized fabric may be used as a sealing sleeve between a prosthetic device and a residual limb.