Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance.

Theoretical and experimental investigations into the thermal excitation of liquid paramagnetic contrast agents using the spin resonance relaxation mechanism are presented. The electronic spin-lattice relaxation time τ1e of gadolinium-based contrast agents, which is estimated at 0.1 ns, is ten orders of magnitude faster than the relaxation time of protons in water.

Performance of black and white South African children on the Wechsler Intelligence Scale for Children--Revised and the Kaufman Assessment Battery.

The validity of traditional intelligence tests for cultural groups that differ from those for whom the tests were normed has come under scrutiny. This is particularly the case for the previously disadvantaged black majority in South Africa. The Kaufman Assessment Battery for Children (K-ABC) is reportedly a relatively nondiscriminatory test of intellectual functioning.

Use of the NAL-AB wordlists as a South African English speech discrimination test.

South Africa still lacks a South African English specific speech discrimination test. As an alternative, this study investigated the use of the Australian English, National Acoustic Laboratories Arthur Boothroyd (NAL-AB) wordlists to assess the speech discrimination of South African English speakers. Thirty South African English speakers were tested at 0, 5, 10, 20 and 25 dBHL (audiometer dial reading) and their performance-intensity functions were compared qualitatively to the NAL-AB wordlist normative data.

Adjustment of children and interaction of parent and child among single mothers in a disadvantaged South African community.

This study investigated the relationships among family status (intact vs single parent), socioeconomic status, parent-child interaction, and children's adjustment in a disadvantaged "Coloured" community in South Africa. Data were collected from 48 mothers, including 12 married mothers of higher socioeconomic status, 12 single mothers of higher socioeconomic status, 12 married mothers of low socioeconomic status, and 12 single mothers of low socioeconomic status. Low socioeconomic status, single mothers rated their children as significantly less adjusted than mothers in the other three groups.

A pilot investigation of high-frequency audiometry in obscure auditory dysfunction (OAD) patients.

The diagnosis of obscure auditory dysfunction (OAD) has been an elusive one, based primarily upon reports of poor speech perception in noise by the patient. Basic audiometric testing reveals hearing within normal threshold limits and it is thought that there may, in part be some subtle psychoacoustic and/or central auditory deficits causing this phenomenon. The use of high-frequency audiometry (HFA) as a test of subclinical cochlear damage has been well documented, especially to monitor the early effects of noise exposure and ototoxic drugs.