A master information carrier for magnetic transfer includes a substrate having an irregularity pattern representing information to be transferred to a slave medium and a magnetic layer formed on the irregularity pattern on the substrate. Therefore, neuroprotective compositions and related methods are provided that employ such neuroprotective compounds, and prodrugs of such compounds, to cause dissociation of Nrf2 from a Keap1Nrf2 complex. , by inhibiting prostaglandin andor COX-2 production, using one or more indolequinazoline alkaloids, preferably in combination with butylated hydroxytoluene. Preferably, the reference voltage is controlled based on the location of the target frequency in relation to the overall operational frequency band, which has been divided into a series of sub-bands. Furthermore, the downhole tool includes a substantially axial fluid pathway through the chamber, wherein the fluid pathway includes at least one inlet proximate the first end and at least one outlet proximate the second end. The gap may be filled with a gas.