Vibrio gastroenteritis in the US Gulf of Mexico region: the role of raw oysters

We examined clinical and epidemiological features of 575 laboratory-confirmed cases of vibrio gastroenteritis in Alabama, Florida, Louisiana, and Texas from 1988 to 1997 (the US Gulf of Mexico Regional Vibrio Surveillance System). Illnesses occurred year round, with peaks in spring and autumn. Illnesses lasted a median of 7 days and included fever in half of patients and bloody stools in 25% of patients with relevant information. Seventy-two percent of patients reported no underlying illnesses. In the week before onset, 236 (53%) of 445 patients for whom data were available ate raw oysters, generally at a restaurant or bar. Educational efforts should address the risk of vibrio gastroenteritis for raw oyster consumers, including healthy individuals. Further studies should examine environmental conditions affecting vibrio counts on seafood and processing technologies to enhance the safety of raw oysters.

Improving audibility with nonlinear amplification for listeners with high-frequency loss

In contrast to fitting strategies for linear amplification that have been frequently refined for listeners with different degrees of hearing loss, we know relatively little about the effects of nonlinear amplification for differing audiometric configurations. The purpose of the current study was to determine whether increases in audibility with nonlinear amplification improved speech recognition to a comparable degree for listeners with sloping sensorineural loss as for a comparison group of listeners with flat sensorineural loss. Consonant recognition was examined as a function of audibility with wide dynamic range compression amplification and with linear amplification. For linearly amplified speech, listeners with flat and sloping loss showed similar improvements in recognition given the same increases in audibility. Results for nonlinearly amplified speech indicated that the listeners with flat loss showed a greater rate of improvement as audibility increases than the listeners with sloping loss. This difference is largely due to superior performance by the listeners with sloping loss for low-audibility speech in comparison to equivalent group performance for high-audibility speech.

Improving speech audibility with wide dynamic range compression in listeners with severe sensorineural loss

OBJECTIVE

In contrast to fitting strategies for linear amplification, which have been refined frequently for listeners with different degrees of hearing loss, we know relatively little about the effects of wide dynamic range compression (WDRC) amplification for listeners with severe auditory thresholds. The primary objective of this study was to determine if increases in audibility with WDRC amplification improved speech recognition to a comparable degree for listeners with different degrees of hearing loss.

DESIGN

Listeners with mild to moderate or severe sensorineural loss were tested on recognition of vowel-consonant-vowel (VCV) syllables and sentences digitally processed with linear and WDRC amplification. The speech materials were presented under conditions of controlled audibility, in which WDRC amplification improved speech audibility over linear amplification. Presentation levels were chosen to provide equivalent increases in audibility with WDRC amplification for both listener groups. A control condition in which audibility was equated for the two amplification conditions was also included.

RESULTS

Recognition results for VCV stimuli indicated that both listener groups received the same benefit from the improved audibility provided by WDRC amplification. Results for sentence recognition showed a greater benefit of WDRC amplification for listeners with mild to moderate than for listeners with severe loss.

CONCLUSIONS

Increasing the amount of audible speech information with WDRC has similar effects on consonant recognition for listeners with different degrees of hearing loss. Differences in sentence recognition for listeners with different degrees of loss may be due to processing effects or to differences in available acoustic information for longer segments of WDRC-amplified speech.

Isolation and identification of 5,7-dimethoxyisoflavone, an inhibitor of Aspergillus flavus from peanuts

An inhibitor of Aspergillus flavus has been isolated form peanuts and identified as 5,7-dimethoxyisoflavone, Authentic 5,7-dimethoxyisoflavone, synthesized from benzyl-2-hydroxy-4,6 dimethoxyphenyl (3), and the isolated compound display identical ultraviolet spectra in methanol, in methanol+sodium methoxide, and in methanol+AlCl3; similar behavior in solvent extraction, column chromatography, TLC, and fungal inhibition.