Abstract: Conventional electronic information retrieval systems using specialist databases assume that the database being searched is appropriate to the search being conducted. The invention solves the problem that the above assumption may be incorrect. It does this by providing mechanisms (4, 4A and 4B) for identifying concepts respectively in: the search input question, a specialist database and a non-specialist database. A comparator 8 and associated mechanisms are able to analyze how the specialist database differs from the non-specialist database and to use this information to derive an indication of the ability of the specialist database to answer the input question. This indication can be fed to the user via interface 1 or in an alternative arrangement could be used to block inappropriate information.

Abstract: Systems and methods for providing and using a teaching aid that enables swimmers to develop correct mechanics and movement patterns of a flip turn. A teaching aid is provided that functions to expedite the teaching and learning of proper flip turn mechanics by providing an object for a swimmer to place his/her hands on and press down for support, tactile feedback and spatial orientation as the swimmer learns to initiate and perform a proper flip turn. Utilization of the teaching aid allows a swimmer to feel and move through the proper mechanics of the flip turn, thereby expediting the swimmer's ability to perform the turn without assistance.