The present invention relates to an oxidation reaction catalyzed by a reaction controlled phase-transfer catalyst having the general formula of R1R2R3R4NxHyA or QmMO3. A generalized multiple threshold scheme for iteratively decoding a received codeword may include generating a bit reliability based on a channel output reliability and an updated bit reliability from a previous decoding iteration, where the bit reliability is updated using a scaling factor and a comparison with a threshold. The defective elements can then be re-mapped to a redundant element at either the appropriate bit or column level based on the data. Indexing devices and methods are also disclosed for successively treating portions of the hollow anatomical structure.