Experiments were conducted to investigate local heat transfer coefficients and flow characteristics of air flow in a 962 lm inner diameter stainless steel microtube (minichannel). The effects of heat loss, axial heat conduction and viscous heating were systematically analyzed. Heat losses during the experiments with gas flow in small diameter tubes vary considerably along the flow length, causi...

Fractional derivatives are well suited to describe wave propagation in complex media. When introduced in classical wave equations, they allow a modeling of attenuation and dispersion that better describes sound propagation in biological tissues. Traditional constitutive equations from solid mechanics and heat conduction are modified using fractional derivatives. They are used to derive a nonlin...

Otosclerosis is a common disorder that leads to conductive hearing loss. Most patients with otosclerosis also have tinnitus, and surgical treatment is known to improve hearing as well as tinnitus. Some patients however experience worsening of tinnitus after the operation, but there are no known factors that allow surgeons to predict who will be at risk. In this prospective observational study o...

BACKGROUND The normal sinus pacemaker complex is an extensive structure within the right atrium. We hypothesized that patients with sinus node disease (SND) would have evidence of diffuse atrial abnormalities. METHODS AND RESULTS Sixteen patients with symptomatic SND and 16 age-matched controls were studied. The following were evaluated: effective refractory periods (ERPs) from the high and l...

The electtical conductivity existing in electrified clouds is computed under the assumption that a primary positive dipole charge distribution exists within the cloud and that the small ion concentrations are controlled by the rate of ion production from cosmic ray ionization, and by the rates of ion loss from the separate processes of ion recombination, diffusion, and conduction. The results s...

OBJECTIVE Research has established that human immunodeficiency virus (HIV) causes hearing loss. Studies have yet to evaluate the impact on quality of life (QOL). This project evaluates the effect of hearing loss on QOL by HIV status. METHODS The study participants were from the Multicenter AIDS Cohort Study (MACS) and the Women's Interagency HIV study (WIHS). A total of 248 men and 127 women ...

Human listeners can perceive speech signals in a voicemodulated ultrasonic carrier from a bone-conduction stimulator, even if the listeners are patients with sensorineural hearing loss. Considering this fact, we have developed a bone-conducted ultrasonic hearing aid (BCUHA). The purpose of this study was to assess the usefulness of the BCUHA in transmission of the emotional state of the speaker...

A 9 year old boy had chronic progressive motor-sensory neuropathy that started in early infancy. He had enlarged nerves and pes cavus deformity. Motor conduction studies showed very dispersed, polyphasic compound muscle action potentials with conduction velocities around 2 m/s. A sural nerve biopsy showed severe loss of myelinated fibres. Two months of treatment with corticosteroids restored mu...

OBJECTIVES To share results and recommendations for management of penetrating cochlear injury. METHODS A patient underwent repair of a penetrating cochlear injury after a projectile led to a traumatic cochleostomy with a narrow miss of the facial nerve and intracranial carotid artery. RESULTS Postoperatively, the patient's audiogram demonstrated a pure tone average of 47.5 dB for air conduc...

A patient with a progressive lower motor neuron syndrome and neurophysiological evidence of motor axon loss, multifocal proximal motor nerve conduction block, and high titres of anti-ganglioside GM1 antibodies. Neuropathological findings included a predominantly proximal motor radiculoneuropathy with multifocal IgG and IgM deposits on nerve fibres associated with a loss of spinal motor neurons....