In September, affordable luxury hotel group CitizenM will roll out stress-reduction musical tracks for business travelers in all its hotels that have in-room iPads. Music scientists at Goldsmiths, University of London developed the musical tracks, part of an album called Music for Brainwaves, with record label Erased Tapes to help business travelers deal with jet lag and anxiety and to help them focus. Based in the Netherlands, CitizenM operates 18 hotels in such cities as London, Paris, New York, Amsterdam, Copenhagen and Kuala Lumpur and will open a property in Boston on Aug. 5th.