Damaged or imperfect hair shafts are treated by: hydrating hair shafts to open flaps of the cuticles layer, applying to the hair shafts amino acids or peptides effective to nourish hair, and compressing the hair shafts under heat by sandwiching the hair shafts between heated plates to cause the amino acids or peptides to penetrate through the cuticle layer and close the openings between the flaps. In one embodiment, a surgical access device is provided that includes a housing having multiple access ports for receiving surgical instruments, and a retractor removably coupled to the housing and having a working channel configured to extend into a body cavity. A device for automatic dosing of the treatment agent forms a component of the storage container and operates purely in a fluid-mechanical manner. The lug is flexible and engages with a helical groove in the inner wall of the base. A shielding layer is formed on the exposed first portion of the workpiece surface. A predetermined compacting force may be programmed into the system for all brewing cycles or dependent upon the brewing substance used.