Abstract: The present disclosure relates generally to the field of diagnostic and prognostic assays for a condition or event of a vascular system such as the cerebrovascular system. An assay is taught herein for monitoring progression of a condition or event of a vascular system such as the cerebrovascular system as well as determining the state or stage of the condition or event. The assay of the present disclosure is also useful in the stratification of a subject based on the stage or development of the condition or event.

Abstract: Apparatus and a method for verifying a credit card transaction has a server with a list stored therein, for each card holder, of transaction numbers and unique codes associated therewith. The card holder is supplied with a data carrier having a selection of those transaction numbers and unique codes. On making a purchase, the card holder supplies the transaction number and associated unique code to the vendor, who has that information checked against the server. Purchase authorisation is refused if the unique codes, for that transaction number, do not match.