Provided is a method including routing a compressed gas from a centrifugal gas compressor through at least one of a plurality of air coolers, and directing air flow through the plurality of air coolers, wherein the plurality of air coolers are arranged adjacent to one another in a single plane that is transverse to the air flow. More particularly, it concerns a needleless syringe for injecting an active principle initially set between an injector comprising at least an injection nozzle contacted with the skin and a wall mobile under the effect of a propelling system pressurizing and expelling the active principle through the injector located at the downstream end of the syringe. A display unit receives the rf transmissions from the traps and identifies and displays the then current state of each trap. The dielectric layer covers at least part of the upright wall portion, at least part of the bottom floor portion, and at least part of the corner portion. An installation kit assists the preparation of the femur and ilium bones, as well as the installation of the implant body into the conditioned femur end and the cup outer socket support to a reconditioned acetabulum defined in the ilium bone. Implementations may reduce the sensitivity of the conversion process to jitter in the sampling clock, thereby reducing noise and providing conversion signals.