Analysis of design parameters of round-window stimulating type electromagnetic transducer by a nonlinear lumped parameter model of implanted human ear

<abstract> <p>Round-window stimulating transducer is a new solution to treat mixed hearing loss. To uncover the factors affecting the round-window stimulation's performance, we investigated the influence of four main design parameters of round-window stimulating type electromagnetic transducer. Firstly, we constructed a human ear nonlinear lumped parameter model and confirmed its validity by comparing the stapes responses predicted by the model with the experimental data. Following this, an electromagnetic transducer's mechanical model, which simulates the floating mass transducer, was built and coupled to the human ear model; thereby, we established a nonlinear lumped parameter model of implanted human ear under round-window stimulation and verified its reliability. Finally, based on this model, the influences of the four main design parameters, i.e., the excitation voltage, the electromechanical coupling coefficient, the support stiffness, and the preload force, were analyzed. The results show that the change of excitation voltage does not alter the system's natural frequency. Chaotic motion occurs when the electromechanical coupling coefficient is small. Meanwhile, the stapes displacement appears to increase firstly and then decrease with the increase of the electromechanical coupling coefficient. The increase of the support stiffness enlarges the resonance frequency of the stapes displacement and reduces the stapes displacement near the resonance frequency, deteriorating the transducer's hearing compensation at low frequency. The preload force can improve the transducer's hearing compensation performance in mid-high frequency region.</p> </abstract>

Study of Ear Biometrics Based Identification System Using Machine Learning

Within the biometric industry, computerized person identification using ear pictures is a hot topic. The ear, like other biometrics like the face, iris, and fingerprints, contains a huge number of particular and unique traits that may be used to identify a person. Due to the mask-wearing scenario, most face detection methods fail in this present international COVID-19 pandemic. The eardrum is a great data source for inactive person authentication since it doesn't necessitate the person we're attempting to pinpoint to cooperate, and the structure of the ear doesn't change significantly over time.. The acquisition of a human ear is also simple because the ear is apparent even while wearing a mask. An ear biometric system can enhance other biometric technology in an automated person identification system by giving authentication cues when other information is unreliable or even missing. We provide a six-layer deep convolutional architecture for ear identification in this paper. On the IITD ear dataset, the deep network's potential efficiency is assessed. The IITD has a detection performance of 97.36 percent for the deep network model and 96.99 percent for the IITD. When paired with a competent surveillance system, this approach can be beneficial in identifying people in a large crowd. Keywords: Biometrics, Person identification, IIT-D, Deep learning, Ear dataset

MECHANISM OF SENSORINEURAL HEARING LOSS CAUSED BY TYPICAL SCLEROSIS OF COCHLEA

It is difficult to measure the cochlea directly because of the ethical problems and the complexity of cochlear structure. Therefore, finite element model (FEM) can be used as an effective alternative research method. An accurate FEM of the human ear can not only help people understand the mechanisms of sound transmission, but also effectively assess the effects of otologic diseases and guide research on the treatment of hearing loss. In this paper, a three-dimensional (3D) FEM of the human normal cochlea is proposed to study the changes in the biomechanical behavior of the cochlear sensory structure caused by the anterior fissure sclerosis and bottom-turn and apex-turn ossification of the cochlear window. The degree and harm of hearing loss caused by diseases are quantitatively predicted, which can deepen the understanding of the biomechanical mechanism of cochlea, and provide theoretical basis for clinical medicine.

Electromagnetic and Acoustic Waves in Bioengineering Applications

The textbook deals with the analysis of oscillations, mechanical and electromagnetic waves and their use in medicine. The individual chapters are based on the theoretical foundations of the issue and describe the use of relevant disciplines in medical practice. The chapter on oscillations is a starting point for explaining the basic principles of waves and focuses on explaining the nature of magnetic resonance. The chapter on mechanical waves explains the nature and properties of sound, infrasound, ultrasound, and medical applications, such as lithotripsy or ultrasonography. The chapter on electromagnetic waves discusses their basic principles, origin and properties, and applications of individual frequency bands from long wavelengths to gamma radiation in therapy and diagnostics. The chapter on wave manifestations explains phenomena such as interference and diffraction and their use in applications such as optical imaging systems, holography, virtual reality, etc. The description complements the explanation of the quantum properties of radiation, which are essential for understanding applications such as laser scalpel, fluorescence microscopy, spectroscopy, generation and detection of X-rays and gamma rays. Special attention is paid to the perception of EM waves by the human eye and the perception of sound by the human ear.

Modelling the Generation of the Cochlear Microphonic

<p>The human ear is a remarkable sensory organ. A normal healthy human ear is able to process sounds covering a wide range of frequencies and intensities, while distinguishing between different components of complex sounds such as a musical chord. In the last four decades, knowledge about the cochlea and the mechanisms involved in its operation has greatly increased, but many details about these mechanisms remain unresolved and disputed. The cochlea has a vulnerable structure. Consequently, measuring and monitoring its mechanical and electrical activities even with contemporary devices is very difficult. Modelling can be used to fill gaps between those measurements that are feasible and actual cochlear function. Modelling techniques can also help to simplify complex cochlear operation to a tractable and comprehensible level while still reproducing certain behaviours of interest. Modelling therefore can play an essential role in developing a better understanding of the cochlea. The Cochlear Microphonic (CM) is an electrical signal generated inside the cochlea in response to sound. This electrical signal reflects mechanical activity in the cochlea and the excitation processes involved in its generation. However, the difficulty of obtaining this signal and the simplicity of other methods such as otoacoustic emissions have discouraged the use of the cochlear microphonic as a tool for studying cochlear functions. In this thesis, amodel of the cochlea is presented which integrates bothmechanical and electrical aspects, enabling the interaction between them to be investigated. The resulting model is then used to observe the effect of the cochlear amplifier on the CM. The results indicate that while the cochlear amplifier significantly amplifies the basilar membrane displacement, the effect on the CM is less significant. Both of these indications agree with previous physiological findings. A novel modelling approach is used to investigate the tuning discrepancy between basilar membrane and CMtuning curves. The results suggest that this discrepancy is primarily due to transversal phase cancellation in the outer hair cell rather than longitudinal phase cancellation along the basilar membrane. In addition, the results of the model suggest that spontaneous cochlear microphonic should exist in the cochlea. The existence of this spontaneous electrical signal has not yet been reported.</p>

Modelling the Generation of the Cochlear Microphonic

<p>The human ear is a remarkable sensory organ. A normal healthy human ear is able to process sounds covering a wide range of frequencies and intensities, while distinguishing between different components of complex sounds such as a musical chord. In the last four decades, knowledge about the cochlea and the mechanisms involved in its operation has greatly increased, but many details about these mechanisms remain unresolved and disputed. The cochlea has a vulnerable structure. Consequently, measuring and monitoring its mechanical and electrical activities even with contemporary devices is very difficult. Modelling can be used to fill gaps between those measurements that are feasible and actual cochlear function. Modelling techniques can also help to simplify complex cochlear operation to a tractable and comprehensible level while still reproducing certain behaviours of interest. Modelling therefore can play an essential role in developing a better understanding of the cochlea. The Cochlear Microphonic (CM) is an electrical signal generated inside the cochlea in response to sound. This electrical signal reflects mechanical activity in the cochlea and the excitation processes involved in its generation. However, the difficulty of obtaining this signal and the simplicity of other methods such as otoacoustic emissions have discouraged the use of the cochlear microphonic as a tool for studying cochlear functions. In this thesis, amodel of the cochlea is presented which integrates bothmechanical and electrical aspects, enabling the interaction between them to be investigated. The resulting model is then used to observe the effect of the cochlear amplifier on the CM. The results indicate that while the cochlear amplifier significantly amplifies the basilar membrane displacement, the effect on the CM is less significant. Both of these indications agree with previous physiological findings. A novel modelling approach is used to investigate the tuning discrepancy between basilar membrane and CMtuning curves. The results suggest that this discrepancy is primarily due to transversal phase cancellation in the outer hair cell rather than longitudinal phase cancellation along the basilar membrane. In addition, the results of the model suggest that spontaneous cochlear microphonic should exist in the cochlea. The existence of this spontaneous electrical signal has not yet been reported.</p>

Anatomical and morphometric study of goat middle ear ossicles (Capra aegagrus hircus)

ABSTRACT The social and economic roles of goat farming in Northeastern Brazil, allied to the fact that the use of goat middle ear ossicles for research and human ear surgery training has not yet been proposed, justify the study of their applicability as an experimental model. The middle ears of 19 goats (Capra aegagrus hircus) from the bone collection of the Laboratory and Didactic Anatomy Museum of Domestic and Wild Animals of the Federal University of Vale do São Francisco (UNIVASF) were dissected. The malleus, incus, and stapes were evaluated regarding their macroscopic morphology and biometry (length, width, and height). Ossicle morphology was similar to sheep, human, and bovine morphology. The malleus was 1.3 times heavier and 2.2 times longer than the incus, and 9.0 times heavier and 3.7 times longer than the stapes. The size relationship was positive between the stapes and the malleus and negative between the stapes and the incus. It is concluded that the middle ear size and the anatomical similarities with human ossicles make goats a useful model for experimental scientific studies, reconstructive surgery practice of the ossicular chain, and human ear surgery training.

Fluency development in an EFL setting: A one-semester study

Language learning activities involving time-pressured repetition of similar content have been shown to facilitate improvements in fluency. However, concerns have been voiced about whether these gains might be offset by reduced levels of grammatical accuracy. This descriptive study tracked the oral proficiency of 32 Japanese university students enrolled in English as a foreign language (EFL) classes over one academic semester during which they regularly completed 3/2/1 fluency development activities. Measures of complexity, accuracy, and fluency (CAF) were analysed to investigate whether any developmental patterns could be identified. The results indicated that over the semester, the students made small, but significant gains in two fluency measures, the mean length of pause and the phonation/time ratio. Despite the relatively small size of the gains, expert ratings of perceived fluency suggested that these fluency improvements were detectable to the human ear. Furthermore, a significant relationship emerged between three of the four CAF measures over the semester. These results suggest that the activities moderately impacted students’ speaking fluency without negatively affecting accuracy or complexity levels; however, further longitudinal research is needed to determine which factors might influence this development, as class performance measures did not account for any of the variation detected.