The present invention is concerned with 3-aryl-isoxazole-4-carbonyl-benzofuran derivatives of formula I wherein R1, R2, and R3 are as defined in the specification and claims and with their pharmaceutically acceptable acid addition salts. A threshold voltage control circuit 5 has an output terminal Vbout controlling the substrate voltage to be outputted to the substrate terminal of each of the two transistors Tr121 and Tr122 included in the differential switch 12 for controlling the threshold voltage of the two transistors of the differential switch. The spatial layer and the linked data set then may be queried using a single input query.