to assess the environmental radioactivity levels and hence to determine the population exposure in kutubdia island, bangladesh the sediment samples were analyzed by using gamma ray spectrometry. in those sediment samples the average activity concentration of natural radionuclides 238u, 232th and 40k were found 15.39±1.67, 38.35±0.76 and 475.51±21.15 bq/kg respectively. the activity concentratio...

The influence of fatiguing sound level and duration on post-exposure temporary threshold shift (TTS) was investigated in two beluga whales (Delphinapterus leucas). The fatiguing sound was half-octave noise with a center frequency of 22.5 kHz. TTS was measured at a test frequency of 32 kHz. Thresholds were measured by recording rhythmic evoked potentials (the envelope following response) to a te...

background: ototoxic chemicals can impair the sense of hearing and balance. in the past decades, the ototoxicity of solvents and their interaction with noise have become evident. this study has been carried out in the shoe manufacturing factory in tehran (iran) with the aim of evaluating the combined effects of noise and toluene on the workers' hearing. materials and methods: this cross-se...

This paper describes a method for determining a semi-empirical, equivalent simple-source model that accounts for the sound radiation in the vicinity of a high-performance military aircraft. The characteristics of the equivalent source are guided by previously reported observations of jet noise, namely that the strengths of the partially correlated sources are distributed asymmetrically. The par...