In this paper, acoustic tweezers which use beam forming performed by a Fresnel zone plate are proposed. The performance has been demonstrated by finite element analysis, including the acoustic intensity, acoustic pressure, acoustic potential energy, gradient force, and particle distribution. The acoustic tweezers use an ultrasound beam produced by a lead zirconate titanate (PZT) transducer oper...

An acousto-optical reconstruction method for acoustic signals using multidirectional light diffraction by finite amplitude ultrasonic pulses is presented. When crossing the ultrasonic field, the far field diffracted laser light intensity of an incident convergent lightbeam becomes modulated in time. It is found that for special conditions, concerning direction of observation, ultrasonic frequen...

Intensity fluctuations were measured during August 2002 near San Diego using 20 and 40 kHz cw and fm signals. Source-receiver separation was 1km; source depths were 10m to 67m; receiver hydrophone depths were 44m to 217m. A 15-element chain of CTD sensors was towed to measure horizontal temperature and salinity with 1m resolution. Comparing the spectra of the acoustic intensity fluctuations and...

Intensity difference limens (DLs) were measured in users of the Nucleus 22 and Clarion v1.2 cochlear implants and in normal-hearing listeners to better understand mechanisms of intensity discrimination in electric and acoustic hearing and to evaluate the possible role of neural adaptation. Intensity DLs were measured for three modes of presentation: gated (intensity increments gated synchronous...

Background: Repeated efforts by researchers to impose voice changes by laryngeal surface electrical stimulation (SES) have come to no avail. This present pre-experimental study employed a novel method for SES application so as to evoke the motor potential of the internal superior laryngeal nerve (ISLN) and create voice changes.Methods: Thirty-two normal individuals (22 females and 10 males) par...

The olivocochlear (OC) pathway is the source of major feedback control of ascending acoustic information. Two main patterns of axonal branching are evident at this and other levels of the auditory pathway: long-distance collaterals and branches involved in feedback-control loops. Only a minority of OC neurons project to both cochlea, consistent with a role for the system in sound localization. ...

Background/introduction Obstruction by the thoracic cage of the high intensity focused ultrasound (HIFU) beam is one of the major challenges in the ablation of abdominal lesions. Several beam shaping methods have been proposed to reduce exposure of the ribs to acoustic energy and to recover focal point intensity. The feasibility of HIFU ablation of a clinically relevant volume applying beam sha...

Characterisation of the spatial peak intensity at the focus of high intensity focused ultrasound transducers is difficult because of the risk of damage to hydrophone sensors at the high focal pressures generated. Hill et al (1994 Ultrasound Med. Biol. 20 259-69) provided a simple equation for estimating spatial-peak intensity for solid spherical bowl transducers using measured acoustic power an...

We report experimental evidence identifying acoustic phonons as the principal source of the excitation-induced-dephasing (EID) responsible for the intensity damping of quantum dot excitonic Rabi rotations. The rate of EID is extracted from temperature dependent Rabi rotation measurements of the ground-state excitonic transition, and is found to be in close quantitative agreement with an acousti...

This study investigates the influence of stress grouping on verbal short-term memory (STM). English speakers show a preference to combine syllables into trochaic groups, both lexically and in continuous speech. In two serial recall experiments, auditory lists of nonsense syllables were presented with either trochaic (STRONG-weak) or iambic (weak-STRONG) stress patterns, or in monotone. The acou...