Experimental study of an implantable fiber-optic microphone on human cadavers.

Hear Res

Medical University of Vienna, Department of Anatomy, Centre for Anatomy and Cell Biology, Waehringerstrasse 13, Vienna 1090, Austria.

Published: October 2021

In this paper, we present the results of an experimental study about a novel fiber optical vibrometer, aimed to be used as a totally implantable fiber-optic microphone for hearing aids. The sensor head, implanted inside the human cadaver middle ear, detects the amplitude of the incus vibrations, which are produced by an external acoustical source. The probe beam of coherent vertical cavity surface emitting laser (VCSEL) radiation is directed to the incus and the phase-modulated reflected beam is captured and demodulated. The problem of interferometric fading was solved using two quasi-quadrature signals, passively produced by the 3 × 3 single-mode fiber-optic coupler, processed by a special embedded algorithm. The implanted optoelectronic module works with very low-power consumption, performs real-time signal processing and outputs an analogue signal proportional to the incus vibration. The amplitude of the incus vibrations at different sound pressure levels (SPL) from 40 to 90 dB and at frequencies from 100 Hz to 10 kHz were measured by the implanted system. The system was evaluated on five cadaver skulls. The measured amplitudes were in the range of 1 pm to 5 nm, depending on the subjected skull and the applied sound pressure.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.heares.2021.108351DOI Listing

Publication Analysis

Top Keywords

experimental study
8
implantable fiber-optic
8
fiber-optic microphone
8
amplitude incus
8
incus vibrations
8
sound pressure
8
study implantable
4
microphone human
4
human cadavers
4
cadavers paper
4

Similar Publications

Introduction: The risk of HCC is twice as high in diabetic patients compared to non-diabetic ones, suggesting that diabetes advances carcinogenesis in the liver through a variety of mechanisms. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been shown to improve liver outcomes, emerging as promising agents to treat hepatocellular carcinoma (HCC) in patients with type 2 diabetes mellitus (T2DM).

Methods: We searched PubMed and Scopus databases for articles presenting an association between SGLT2is and HCC to explore the putative mechanisms of action underlying the anti-proliferative activity of SGLT2is.

View Article and Find Full Text PDF

Because of high mutation rates, viruses constantly adapt to new environments. When propagated in cell lines, certain viruses acquire positively charged amino acids on their surface proteins, enabling them to utilize negatively charged heparan sulfate (HS) as an attachment receptor. In this study, we used enterovirus A71 (EV-A71) as model and demonstrated that unlike the parental MP4 variant, the cell-adapted strong HS-binder MP4-97R/167G does not require acidification for uncoating and releases its genome in the neutral or weakly acidic environment of early endosomes.

View Article and Find Full Text PDF

Potential Energy Curves of Hydrogen Halides HX(F, Cl, Br) with the -DMFT Method.

J Phys Chem A

December 2024

Institute of atomic and molecular physics, Jilin University, Changchun 130012, China.

The information entropy based on the occupation numbers has been found to play a central role in a description of electron correlation within the density-matrix functional theory [-DMFT, see , 128, 013001]. In this article, the -DMFT method is applied to predict potential energy curves, equilibrium bond lengths, and harmonic vibrational frequencies for the hydrogen halides: HF, HCl, and HBr. The results are compared with other theoretical calculations and experimental spectroscopic data.

View Article and Find Full Text PDF

With a view towards the development of molecular spintronics, non-linear optics, and qubits, a great amount of research effort aims to establish the factors which govern the spin classification of diradicals. Electron spin resonance (ESR) is an indispensable tool for such research. However, in some cases, the mere presence of an ESR spectrum is insufficient to ascertain that the presumed diradical is indeed a triplet state.

View Article and Find Full Text PDF

Recent years have witnessed an intense effort to unravel magnetic field effects in electrocatalysis, as they can enhance the performance of common electrocatalysts. Both experimental and theoretical studies have shown that magnetic fields may affect, among others, the macroscopic spin-orbital ordering, charge transport, bubble release, and electron transfer kinetics. This paper highlights Electrochemical Impedance Spectroscopy (EIS) as a tool to analyze and separate the effects of magnetic field on both the oxygen reduction and evolution reactions at cobalt iron oxide electrodes.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!