An embolus filter introducer system has a symmetric introducer sheath with a filter inside. To select the sensors, levels of the signals are compared between a respiratory frequency band and another frequency band. For some embodiments, such systems and methods may be used to allow a user to set a desired wavelength and bandwidth of a short pulse laser system for operation at those parameters without further adjustment by the user. Further, the transmission shaft is disposed passing through the spacer and the two bearings, and the impeller is disposed at the second side of the housing and is coupled to an end of the transmission shaft. A C\u2014Ta\u2014O material is used for at least any one of first and second boundary layers which are in contact with a recording layer. The electrical connector further comprises a retaining member defining a latching surface.