Pumping system comprising: a progressive cavity pump comprising a helical rotor inside a helical cavity of an outer stator; motor means for driving the rotor, with a motor shaft coaxial to the axis of the stator cavity; and an intermediate shaft coupled, at its ends, by respective couplings, to the rotor shaft and to the motor shaft. The sensor includes a sample chamber to hold a sample in electrolytic contact with a working electrode, and in at least some instances, the sensor also contains a non-leachable or a diffusible second electron transfer agent. Asynchronous data interchanges enabled through the use of XML allow for more efficient and effective resource utilization and time. In some embodiments the sacrificial layer may be configured to survive relatively high temperature processing without substantially affecting the performance of the conversion layer, and to facilitate removal of the substrate via laser lift off. At least a portion of the base is substantially parallel to a surface of a portion of the ring and at least a portion of the transverse face is substantially perpendicular to the surface of the portion of the ring.