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Introduction- The earlobe is formed by tough areola and adipose tissue, lacking the firmness and elasticity of the rest of the ear auricle. The study of earlobe attachment, as a morphogenetic trait can be used to investigate the diversity that arises within and among different populations due to genetic variations. Materials and methods- The present longitudinal randomized study was carried on randomly selected 100 families, residing in Sriganganagar Rajasthan. Digital camera, USB Cable and laptop were used for the study. Results- Out of total 158 offspring 86.08% are free and 13.92% are attached. Males and females displayed the highest frequency of free earlobes. There is no significant gender difference in the pattern of earlobe attachment. Conclusion- The free earlobe is more predominant than attached earlobe and this study investigated an inheritance pattern of simple dominance recessive pattern where free earlobes are dominant over attached earlobes. [ABSTRACT FROM AUTHOR]

Nowadays, the use of the human ear images gains importance for the sustainability of biometric authorization and surveillance systems. Contemporary studies show that such processes can be done semi-automatically or fully automatically, instead of being done manually. Due to the fact that deep learning uses abstract features (i.e., representation learning), it reaches quite high performance values compared to classical methods. In our study, a synergistic gender recognition approach based on hybrid deep learning was created based on the use of human ear images in classifying people fully automatically according to their gender. By means of hybridization, hybrid deep neural network architectural models are used, which include both convolutional neural network component and recurrent neural network type components together. In these models, long-short term memory and gated recurrent unit are taken as recurrent neural network type components. Thanks to these components, the hybrid model extracts the relational dependencies between the pixel regions in the image very well. On account of this synergistic approach, the gender classification accuracy of hybrid models is higher than the standalone convolutional neural network model in our study. Two different image datasets with gender marking were used in our experiments. The reliability of the experimental results has been proven by objective metrics. In the conducted experiments, the highest values in gender recognition with hybrid models were obtained with the test accuracy of 85.16% for the EarVN dataset and 87.61% for the WPUT dataset, respectively. Discussion and conclusions are included in the last section of our study. [ABSTRACT FROM AUTHOR]

The growth of consumer electronic products is encouraged by innovations and has stimulated the persistent development of earphones for high-quality sound reproduction. Earbud earphone is located in the concha of the human ear facing an ear-canal. The placement of earphones in the concha plays a remarkable role in the sound pressure level response of an earphone. In this study, ten earphones were tested for frequency response and total harmonic distortion using head and torso simulator in an anechoic chamber. Three positions and two orientations of earphones in the concha were identified for measurement. Based on the responses of all earphones at all orientations and positions, it is concluded that there is a variation in the frequency response and total harmonic distortion. Even though the variation is small in magnitude, its effect on sound perception, sound exposure, and the hearing threshold is phenomenal. Based on the proposition presented in this work and the safe daily sound exposure, it has been determined that the variation in the frequency response affects the perceived loudness of sound and can cause significant differences in the daily sound exposure limit for a human being. [ABSTRACT FROM AUTHOR]

Hearing damage induced by blast exposure is a common injury in military personnel involved in most operation activities. Personal hearing protection devices such as earplugs come as a standard issue for Service members; however, it is not clear how to accurately evaluate the protection mechanisms of different hearing protection devices for blast overpressures (BOP). This paper reports a recent study on characterization of earplugs' protective function to BOP using human cadaver ears and 3D finite element (FE) model of the human ear. The cadaver ear mounted with pressure sensors near the eardrum (P1) and inside the middle ear (P2) and with an earplug inserted was exposed to BOP in the blast test chamber. P1, P2, and BOP at the ear canal entrance (P0) were simultaneously recorded. The measured P0 waveform was then applied at the ear canal entrance in the FE model and the P1 and P2 pressures were derived from the model. Both experiments and FE modeling resulted in the P1 reduction which represents the effective protection function of the earplug. Different earplugs showed variations in pressure waveforms transmitted to the eardrum, which determine the protection level of earplugs. [ABSTRACT FROM AUTHOR]

• The morphological characters of the ear are a tool in physiognomic identification. • Most of the characters of the ear are associated with each other. • When there is a positive association, only one character should be considered. • The characters with negative association have a greater identification weight. The aim of this paper is to provide information on dependency relationships between the morphological characters of the external ear and their importance in physical identification. At present, there is a lack of population data in this field, and little research has been published. Our study sample consisted of 281 Spanish university students of European descent aged between 18 and 31 years old. We analysed a total of 562 ears. For a large number of characters, we found a dependency between anatomically related characters, confirming our hypothesis. For example, we found relationships between ear shape and protrusion, between rolling of the superior and posterior helix, and between the upper and lower parts of the scapha. However, our results also indicated that some anatomically related characters did not present relationships. Thus, we found no dependency between contour shape of the supero-posterior helix and rolling of the posterior helix or between intertragic incisure shape and tragus or antitragus shape. In addition, we found that some characters that are not anatomically related also showed relationships. These included rolling of the superior helix and intertragic incisure shape, and contour shape of the superior helix and the inferior part of the scapha. These results are of great importance and should be taken into account in forensic applications. [ABSTRACT FROM AUTHOR]

Hearing damage induced by blast exposure is a common injury in military personnel involved in most operation activities. Personal hearing protection devices such as earplugs come as a standard issue for Service members; however, it is not clear how to accurately evaluate the protection mechanisms of different hearing protection devices for blast overpressures (BOP). This paper reports a recent study on characterization of earplugs' protective function to BOP using human cadaver ears and 3D finite element (FE) model of the human ear. The cadaver ear mounted with pressure sensors near the eardrum (P1) and inside the middle ear (P2) and with an earplug inserted was exposed to BOP in the blast test chamber. P1, P2, and BOP at the ear canal entrance (P0) were simultaneously recorded. The measured P0 waveform was then applied at the ear canal entrance in the FE model and the P1 and P2 pressures were derived from the model. Both experiments and FE modeling resulted in the P1 reduction which represents the effective protection function of the earplug. Different earplugs showed variations in pressure waveforms transmitted to the eardrum, which determine the protection level of earplugs. [ABSTRACT FROM AUTHOR]

Rupture of the eardrum or tympanic membrane (TM) is one of the most frequent injuries of the ear after blast exposure. To understand how the TM damage is related to blast wave direction, human cadaver ears were exposed to blast waves along three directions: vertical, horizontal, and front with respect to the head. Blast overpressure waveforms were recorded at the ear canal entrance (P0), near the TM (P1), and inside the middle ear (P2). Thirteen to fourteen cadaver ears were tested in each wave direction and the TM rupture thresholds were identified. Results show that blast wave direction affected the peak P1/P0 ratio, TM rupture threshold, and energy flux distribution over frequencies. The front wave resulted in lowest TM rupture threshold and the horizontal wave resulted in highest P1/P0 ratio. To investigate the mechanisms of TM injury in relation to blast wave direction, the recorded P1 waveforms were applied onto the surface of the TM in a three-dimensional finite element model of the human ear and distributions of the stress in TM were calculated. Modeling results indicate that the sensitivity of TM stress change with respect to P1 pressure (dσ/dP1) may characterize mechanical damage of the TM in relation to blast waves. [ABSTRACT FROM AUTHOR]

In this paper, PATRAN software was used to establish a complete 3D finite element model of human ears and it was then combined with NASTRAN software to analyze frequency responses. This paper conducted a detailed analysis on the dynamic parameters including umbo and stapes displacements of normal human ears under sound pressures 90 dB and 105 dB. The numerically computational results were compared with experimental data. When the analyzed frequency was less than 1000 Hz, the computational result of numerical simulation was well consistent with the upper limit. When the analyzed frequency was more than 1000 Hz, the computational result of numerical simulation was well consistent with the lower limit. Therefore, the numerically computational model was reliable. In addition, based on the verified model, this paper studied vibration characteristics of spiral basilar membrane after replacing artificial auditory ossicle based on the whole hearing system and found that vibration characteristics of spiral basilar membrane had an obvious change at low and high frequencies after replacing artificial auditory ossicle TORP. Using finite element method to analyze vibration characteristics of spiral basilar membrane can well predict the hearing recovery effect after replacing artificial auditory ossicle. Compared with normal ears, the vibration level of spiral basilar membrane after replacing artificial auditory ossicle has slowed down in 100 Hz-600 Hz, 2000 Hz-4000 Hz and 7000 Hz-10000 Hz, and has been strengthened in 600 Hz-2000 Hz and 4000 Hz-7000 Hz, which provided some help for the hearing recovery at the high-frequency band. [ABSTRACT FROM AUTHOR]

This paper used PATRAN/NASTRAN software to establish a three-dimensional finite element model of human ear and conduct dynamic simulation of hearing system. The correctness of the finite element model was verified through analyzing the tympanic membrane displacement of normal human ear under the sound pressure of 80 dB and comparing with the experimental data. Based on the verified model, this paper qualitatively and quantitatively studied and compared the influence of artificial auditory ossicle with 7 kinds of common materials (titanium, stainless steel, teflon, porous polyethylene, alumina ceramic, EH composites and hydroxylapatite ceramics) on the sound conduction of human ear and the effect of postoperative hearing recovery under different sound pressures (50 dB, 80 dB, 105 dB and 120 dB) at 100-10000 Hz. Results showed that the hearing recovery of human ear had the same effect after replacing artificial auditory ossicle under different sound pressures with different frequency. At different frequencies with the same sound pressure, the postoperative hearing of human ear had different effects after replacing different materials of artificial auditory ossicle. Artificial auditory ossicle of hydroxylapatite ceramics, stainless steel and alumina ceramic had better effect on sound conduction at low frequencies, while artificial auditory ossicle of porous polyethylene and teflon had better effect on sound conduction at high frequencies. Under different sound pressures, replacing artificial auditory ossicle with 7 kinds of common materials showed little difference in the hearing recovery of human ear at each frequency band and had a stable influence on the sound conduction of human ear. [ABSTRACT FROM AUTHOR]

The finite element (FE) method was used to analyze the effect of coupling conditions between the actuator and the round window membrane (RWM) on the performance of round window (RW) stimulation. A FE model of the human ear consisting of the external ear canal, middle ear and cochlea was firstly developed, and then validation of this model was accomplished through comparison between analytical results and experimental data in the literature. Intracochlear pressure were derived from the model under normal forward sound stimulation and reverse RW stimulation. The equivalent sound pressure of RW stimulation was then calculated via comparing the differential intracochlear pressure produced by the actuator and normal ear canal sound stimulus. The actuator was simulated as a floating mass and placed onto the middle ear cavity side of RWM. Two aspects about the actuator coupling conditions were considered in this study: (1) the cross-section area of the actuator relative to the RWM; (2) the coupling layer between the actuator and the RWM. The results show that smaller actuator size can improve the implant performance of RW stimulation, and size requirements of the actuator can also be reduced by introducing a coupling layer between the actuator and RWM, which will benefit the manufacture of the actuator. [ABSTRACT FROM AUTHOR]

Abstract: The ossicular chain of the human middle ear has a key role in sound conduction since it transfers vibrations from the tympanic membrane to the cochlea, connecting the outer and the inner part of the hearing organ. This study reports firstly a description of the main anatomical features of the middle ear to introduce a detailed survey of its biomechanics, focused on model development, with a collection of geometric, inertial and mechanical/material parameters. The joint issues are particularly discussed from the perspective of developing a model of the middle ear both explanatory and predictive. Such a survey underlines the remarkable dispersion of data, due also to the lack of a standardization of the experimental techniques and conditions. Subsequently, a 3D multi-body model of the ossicular chain and other structures of the middle ear is described. Such an approach is justified as the ossicles were proven to behave as rigid bodies in the human hearing range and was preferred to the more widely used finite element one as it simplifies the model development and improves joint modeling. The displacement of the umbo (a reference point of the tympanic membrane) in the 0.3–6kHz frequency range was defined as input of the model, while the stapes footplate displacement as output. A parameter identification procedure was used to find parameter values for reproducing experimental and numerical reference curves taken from the literature. This simple model might represent a valid alternative to more complex models and might provide a useful tool to simulate pathological/post-surgical/post-traumatic conditions and evaluate ossicular replacement prostheses. [Copyright &y& Elsevier]

Abstract: Due to the lack of appropriate scaffolds, the in vitro engineering of cartilage tissue with a sophisticated structure, such as a human ear, remains a great challenge. Although polyglycolic acid (PGA) has become one of the most successful scaffolds for cartilage regeneration, how to overcome its limitations in achieving desirable mechanical strength and accurate control over shape remains an unsolved problem. In this study, the mechanical strength of PGA scaffold was enhanced by coating with polylactic acid (PLA). The content of PLA was optimized by balancing the scaffold''s biocompatibility and mechanical strength. The PLA/PGA scaffold was then fabricated into a human ear-shape mirror-symmetrical to a normal ear by pressing the scaffold in the ear negative molds, which were fabricated by the computer aided design and manufacturing (CAD/CAM) technique according to the CT scan data from the normal ear. The ear-shaped scaffold reached a similarity level of over 97% compared to the positive ear mold by the shape analysis using a 3D laser scan system. Most importantly, after chondrocyte seeding, the constructs largely retained the original shape during culture with a similarity level of over 84%. Furthermore, the constructs formed ear-shaped cartilage-like tissues at 12 weeks, which revealed a tissue structure with abundant cartilage extracellular matrices and mature lacuna. Additionally, the ear-shaped cartilage at 12 weeks also exhibited fine elasticity and good mechanical strength. These results may provide a useful strategy for reconstructing cartilage tissue with complicated shapes such as a human ear by an in vitro engineering approach. [Copyright &y& Elsevier]