Sound localization by the human auditory system is known to be ineffective underwater. In a research study at the Acoustic Research Laboratory, we introduce additional directional cues from ultra-sonic frequency components. This enables us to work with smaller wavelengths and build simple, small, directional receivers in order to introduce Inter-aural… (More)
with targets placed at ranges exceeding any attempted to date and to produce their acoustic images. The data from these recordings are under analysis and some part of it is presented in this paper.
We present a rare indirect nontraumatic cerebrospinal fluid (CSF) fistula secondary to a fourth ventricle ependymoma. The fistula resulted from rupture of the left temporal horn, distant from the tumour. The fistula was well demonstrated by MRI. High-resolution CT demonstrated a defect in the roof of the sphenoid sinus, but no leakage of CSF was seen on CT… (More)