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Bone conduction implants enable patients to hear via vibrations transmitted to the skull. The main constraint of current bone conduction implants is their maximum output force level. Stimulating closer to the cochlea is hypothesized to increase efficiency and improve force transfer, addressing this limitation. This study evaluated stimulation at four positions in human cadaveric specimens: the cochlear promontory, the posterior wall of the outer ear canal, the lateral semi-circular canal, and the standard Bone-Anchored Hearing Aid (Baha) location. To assess potential hearing sensation, three objective measures were simultaneously recorded. For intracochlear pressure and promontory velocity, stimulating at the lateral semi-circular canal and promontory results in the highest response, with a gain of up to 20 dB. Ear canal pressure shows less conclusive results, with significant differences at only a few frequencies. These findings suggest that stimulation closer to the cochlea offers higher efficiency, which could benefit patients needing higher output force levels than currently available or those eligible for electro-vibrational stimulation, e.g. a cochlear implant combined with a bone conduction device. [ABSTRACT FROM AUTHOR]

A cochlear implant is a neuroprosthetic device that can restore speech perception for people with severe to profound hearing loss. Because of recent evolutions, a growing number of people with a cochlear implant have useful residual acoustic hearing. While combined electro-acoustic stimulation has been shown to improve speech perception for this group of people, some studies report limited adoption rates. Here, we present electro-vibrational stimulation as an alternative combined stimulation strategy that similarly targets the full cochlear reserve. This novel strategy combines the electrical stimulation by the cochlear implant with low-frequency bone conduction stimulation. In a first evaluation of electro-vibrational stimulation, speech perception in noise was assessed in 9 subjects with a CI and symmetrical residual hearing. We demonstrate a statistically significant and clinically relevant improvement for speech perception in noise of 1.9 dB signal-to-noise ratio. This effect was observed with a first prototype that provides vibrational stimulation to both ears with limited transcranial attenuation. Future integration of electro-vibrational stimulation into one single implantable device could ultimately allow cochlear implant users to benefit from their low-frequency residual hearing without the need for an additional insert earphone. [ABSTRACT FROM AUTHOR]

This study investigated how metabolite analysis can explain differences in tissue composition and size in fish from different habitats. We, therefore, studied Nile tilapia (Oreochromis niloticus) from three Ethiopian lakes (Gilgel Gibe, Ziway, and Langano) using dried bloodspot (DBS) analysis of carnitine esters and free amino acids. A total of sixty (N = 60) Nile tilapia samples were collected comprising twenty (n = 20) fish from each lake. The proximate composition of the targeted tissues (muscle, skin, gill, gut, and liver) were analyzed. The DBS samples were analyzed for acylcarnitine and free amino acid profiles using quantitative electrospray tandem mass spectrometry. Metabolite ratios were calculated from relevant biochemical pathways that could identify relative changes in nutrient metabolism. The mean weight of Nile tilapia sampled from each lake showed weight variation among the lakes, fish from Lake Ziway were largest (178 g), followed by Gilgel Gibe reservoir (134 g) and Lake Langano (118 g). Fish from Gilgel Gibe showed significantly higher fat composition in all tissues (P < 0.05) except the liver in which no significant variation was observed. The source of fish affected the tissue fat composition. Marked differences were observed in Nile tilapia metabolic activity between the lakes. For instance, the lower body weight and condition of the fish in Lake Langano coincided with several metabolite ratios pointing to a low flow of glucogenic substrate to the citric acid cycle. The low propionyl to acetylcarnitine ratio (C3:C2) in Gilgel Gibe fish is indicating that more of the available acetyl CoA is not led into the citric acid cycle, but instead will be used for fat synthesis. The metabolic markers for lipogenesis and metabolic rate could explain the high-fat concentration in several parts of the body composition of fish from Gilgel Gibe. Our results show that nutrition-related blood metabolite ratios are useful to understand the underlying metabolic events leading to the habitat-dependent differences in the growth of Nile tilapia, and by extension, other species. [ABSTRACT FROM AUTHOR]

In the semi-autobiographic novel Nekropola (Necropolis, 1966) of the Slovene author Boris Pahor (born in 1913), the main character revisits the concentration camp Natzweiler-Struthof where he spent part of his imprisonment during the Second World War. During this visit the world of the concentration-camp prisoner and the world of the concentration-camp survivor are reunited. In both worlds the (lack of) connection between the protagonist and the surrounding characters, and the hereto related emotional spectrum of loneliness (alienation, distance, solitude) occupy a central position. Earlier research pointed out that the reunion of the concentration-camp world in the memories of the protagonist and the world he lives in now emphasizes the discrepancy between these two worlds. Based on the narrative concepts described by Michael Rothberg (timelessness, falsifiability and normality vs the extreme), this article indicates that this discrepancy actually does not only originate in the confrontation between the world of the past and the present. Illustrated by the very different and sometimes opposite effects of the constant confrontation with loneliness, distance and alienation, present paper reveals that this hiatus between past and present is embedded in the state of mind, or rather, in the identity of the main character. [ABSTRACT FROM AUTHOR]