Abstract: A waveguide for use in a loudspeaker. The waveguide is positioned within a loudspeaker enclosure and connect to a low frequency transport duct of the loudspeaker. The waveguide has a hollow body which is perforated with apertures. The body presents a high mechanical impedance to the low frequency waves increasing the duct input impedance of the loudspeaker which improves transmission of the low frequency waves to the exterior of the loudspeaker enclosure.

Abstract: This invention provides thrombolytic agents and methods for making and using thrombolytic agents. Specifically, the invention provides thrombolytic agents comprising a thrombolytic proteinase and a specific binding peptide that specifically binds at the site of blood clots and thrombi in vivo. The invention particularly provides chemically crosslinked conjugates of a thrombolytic proteinase and a plurality of specific binding peptide. Methods for producing such chemically crosslinked conjugates and methods for using such conjugates for eliminating thrombi in vivo to alleviate pathological conditions caused thereby are also provided. The preferred thrombolytic proteinase in the conjugate is fibrolase obtainable from Agkistrodon contortrix confortrix venom.