Apparatus for measuring the viscosity of a Newtonian fluid, includes a tubular housing which defines an internal cavity; a fluid restriction structure disposed in a first portion of the cavity; and a pressure measuring device disposed to measure the differential pressure in the cavity of the fluid which has flowed through the fluid restriction structure. The plug system comprises solid, porous or hollow microcapsules composed of a biodegradable biocompatible polymer. The invention is characterized in that at least one low-turbulence displacement air stream of purified air is generated at least in the second physical area near the at least one air jet and said at least one displacement air stream is directed primarily in the same direction as the at least one air jet. The actuator arm includes an arm base disposed adjacent the actuator body. The method involves identifying a user preference, providing at least one data feed containing information related to the user preference, selecting preferred data from the data feed corresponding to the user preference, pre-loading information that matches the preferred data from the host server to the display device, and presenting the preferred data through the display device. The probe may be a chemical conjugate of a monofunctional phosphorescent porphyrin dye and a poly, polypeptide or polysaccharide.