In some embodiments, an apparatus and a system, as well as a method and an article, may operate to couple, in a substantially fluid-tight manner, a first tubular member (140′) carrying a first set of tubular member conductors (124′) to a hollow cylinder (104). The hollow cylinder may include two or more sets of insulators having an equal number of insulating elements (120, 128) located on the outer surface of the hollow cylinder, and two or more sets of conductors (110, 116) having an equal number of conducting elements defining pairs of conducting elements located on the outer surface . Each of the pairs of conducting elements may be insulated from the other pairs of conducting elements by the sets of insulators. Various embodiments may also operate to couple, in a substantially fluid-tight manner, a second tubular member (140″) carrying a second set of tubular member conductors to the hollow cylinder.