A method and system create a data structure from an obfuscated data structure. The method includes reducing a plurality of parasites infecting an aquatic animal by administrating to the aquatic animal a compound comprising propyl propane thiosulfonate having the formula R\u2014SOa-S\u2014R, where R represents n-propyl group and a is 2. The first tunnel insulating layer and the second tunnel insulating layer may be sequentially stacked on the semiconductor substrate.