A method and apparatus employing selectable hardware accelerators in a data driven architecture are described. In the most preferred embodiments of the present invention, at least one amorphous layer is provided in an MTJ stack to increase the smoothness of the various layers in the MTJ stack while also enhancing the magnetic performance of the resulting device. The first retainer portion is removably attached to the second retainer portion. The presentation invention, though, provides an efficient method to identify interested subscribers for each XML document by indexing queries utilizing a graphical structure of nodes. Thereby, a position-fix accuracy is evaluated appropriately, without needing external data, such as autonomous navigation information. The inner end portion of the sleeve is clamped between the lamp base and a socket when the lamp is screwed into the socket, thereby to support the sleeve adjacent to the lamp.