Numerical spatial impulse response calculations for a circular piston radiating in a lossy medium.

Exact analytical expressions for the spatial impulse response are available for certain transducer geometries. These exact expressions for the spatial impulse response, which are only available for lossless media, analytically evaluate the Rayleigh integral to describe the effect of diffraction in the time domain. To extend the concept of the spatial impulse response by including the effect of power law attenuation in a lossy medium, time-domain Green's functions for the Power Law Wave Equation, which are expressed in terms of stable probability density functions, are computed numerically and superposed.

Can vestibular rehabilitation exercises help patients with concussion? A systematic review of efficacy, prescription and progression patterns.

Objective: Concussion symptoms normally resolve within 7-10 days but vertigo, dizziness and balance dysfunction persist in 10-30% of cases causing significant morbidity. This study systematically evaluated the evidence supporting the efficacy, prescription and progression patterns of vestibular rehabilitation therapy (VRT) in patients with concussion.

Design: Systematic Review, guided by PRISMA guidelines and presenting a best evidence synthesis.