Abstract: Actuating mechanism for rapidly and selectively moving a threaded screw and nut member combination into or out of threaded engagement, particularly for use of the screw as a control fluid plunger to pressurize angioplasty balloon catheters, or the like, which mechanism includes a housing and a threaded screw slideably displaceable through the housing, and a nut member having partial threads engageable and disengageable with the threaded screw structure. A carriage structure is secured to the nut structure and arranged to enable reversibly translating motion together with the nut member relative to the screw structure to enable the selectively threaded engageability of the partially threaded nut member with the screw structure.

Abstract: A method of marking the skin of a piece of produce with an identifying mark includes the steps of: providing a piece of produce; providing a laser which emits a high intensity light beam to mark the skin of the produce and which laser light beam can be controlled such that a depth of the mark formed on the skin is controlled; relatively moving the piece of produce and the laser; directing the laser light beam along a predetermined path along the produce skin which corresponds to the identifying mark to be applied on the produce skin; and controlling the depth the laser light beam impacts the produce skin such that identifying mark does not penetrate completely through the produce skin to the meat of the produce. Movement of the piece of produce is effected past the laser device while effecting movement of the laser device relative to the piece of produce.