A method for compressing and decompressing files is provided. The non-circular cross-sectional shape may be provided to the instrument by providing peripheral projections or fins along the length of the portion or by providing the periphery of the portion with a polygonal shape. It is preferred that the layer of the crosslinked polymer is substantially nonporous or solid, and ion conductive, and that the crosslinked polymer has in the molecule oxetanyl groups which are capable of cation polymerization. In one preferred embodiment of the invention, the one or more polypeptides are used for treatment of HIV itself via medication taken orally or parentally. An apparatus for manufacturing a cutting insert green body having undercuts includes top and bottom dies which abut each other and top and bottom punches which slide in their respective dies. 5 and at least one element selected from the group consisting of B, P, Li, Ge, Al, and V, and a carbonaceous material.