A u-shaped trailer frame that includes a drawbar that is connectable to a trailer hitch. In some variations the implant is configured as a bone implant that includes a bone-screw or intramedullary rod like body configured to receive a treatment cartridge having a plurality of ion-releasing members configured as an anode that can controllably engage with a catheter to turn galvanic release of ions onoff as desired. Each processor is an endpoint within a data storage system. The first host includes a substituted or unsubstituted polycyclic fused aromatic skeleton, the skeleton having 10 to 30 ring-forming atoms not including an atom of a substituent. The electrical connection may include a fixed impedance or resistance, or may include a variable impedance unit that automatically varies impedance based on a voltage difference between the curved conductive surface and the grounded central rod.