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The present study focuses on auditory discrimination abilities in older adults aged 65–89 years. We applied the “Leipzig inventory for patient psychoacoustic” (LIPP), a psychoacoustic test battery specifically designed to identify deficits in central auditory processing. These tests quantify the just noticeable differences (JND) for the three basic acoustic parameters (i.e., frequency, intensity, and signal duration). Three different test modes [monaural, dichotic signal/noise (s/n) and interaural] were used, stimulus level was 35 dB sensation level. The tests are designed as three-alternative forced-choice procedure with a maximum-likelihood procedure estimating p = 0.5 correct response value. These procedures have proven to be highly efficient and provide a reliable outcome. The measurements yielded significant age-dependent deteriorations in the ability to discriminate single acoustic features pointing to progressive impairments in central auditory processing. The degree of deterioration was correlated to the different acoustic features and to the test modes. Most prominent, interaural frequency and signal duration discrimination at low test frequencies was elevated which indicates a deterioration of time- and phase-dependent processing at brain stem and cortical levels. LIPP proves to be an effective tool to identify basic pathophysiological mechanisms and the source of a specific impairment in auditory processing of the elderly.

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A method for arsenic speciation in shark, shrimp, squid, oyster and scallop using liquid chromatography coupled to inductively coupled plasma triple quadrupole mass spectrometry (LC-ICP-MS/MS) was proposed. Suitable sensitivity and selectivity by LC-ICP-MS/MS were obtained using 10 mmol L (NH)HPO diluted in 1% methanol (pH 8.65) as mobile phase. Recoveries from 90 to 104% for arsenobetaine (AsB), arsenite [As(III)], dimethylarsinic acid (DMA), monomethylarsonic acid (MMA) and arsenate [As(V)] were obtained for all samples. A certificated reference material was also analyzed and the sum of As species was in agreement with the total As concentration. Limits of quantification (LOQ) for AsB, As(III), DMA, MMA, and As(V) were 6, 30, 6, 12 and 26 ng g, respectively. Higher concentration of AsB was found in all seafood, while As(III) and DMA were found only in oyster. Arsenate was found in squid and scallops, and MMA was below the LOQ in all samples.

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