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https://www.readbyqxmd.com/read/28712672/noise-induced-cochlear-synaptopathy-in-rhesus-monkeys-macaca-mulatta
#1
M D Valero, J A Burton, S N Hauser, T A Hackett, R Ramachandran, M C Liberman
Cochlear synaptopathy can result from various insults, including acoustic trauma, aging, ototoxicity, or chronic conductive hearing loss. For example, moderate noise exposure in mice can destroy up to ∼50% of synapses between auditory nerve fibers (ANFs) and inner hair cells (IHCs) without affecting outer hair cells (OHCs) or thresholds, because the synaptopathy occurs first in high-threshold ANFs. However, the fiber loss likely impairs temporal processing and hearing-in-noise, a classic complaint of those with sensorineural hearing loss...
July 8, 2017: Hearing Research
https://www.readbyqxmd.com/read/28708814/chirp-evoked-otoacoustic-emissions-and-middle-ear-absorbance-for-monitoring-ototoxicity-in-cystic-fibrosis-patients
#2
Angela C Garinis, Douglas H Keefe, Lisa L Hunter, Denis F Fitzpatrick, Daniel B Putterman, Garnett P McMillan, Jeffrey A Gold, M Patrick Feeney
OBJECTIVES: The goal of this study was to investigate the use of transient-evoked otoacoustic emissions (TEOAEs) and middle ear absorbance measurements to monitor auditory function in patients with cystic fibrosis (CF) receiving ototoxic medications. TEOAEs were elicited with a chirp stimulus using an extended bandwidth (0.71 to 8 kHz) to measure cochlear function at higher frequencies than traditional TEOAEs. Absorbance over a wide bandwidth (0.25 to 8 kHz) provides information on middle ear function...
July 13, 2017: Ear and Hearing
https://www.readbyqxmd.com/read/28696404/effect-of-wind-farm-noise-on-local-residents-decision-to-adopt-mitigation-measures
#3
Anabela Botelho, Pedro Arezes, Carlos Bernardo, Hernâni Dias, Lígia M Costa Pinto
Wind turbines' noise is frequently pointed out as the reason for local communities' objection to the installation of wind farms. The literature suggests that local residents feel annoyed by such noise and that, in many instances, this is significant enough to make them adopt noise-abatement interventions on their homes. Aiming at characterizing the relationship between wind turbine noise, annoyance, and mitigating actions, we propose a novel conceptual framework. The proposed framework posits that actual sound pressure levels of wind turbines determine individual homes' noise-abatement decisions; in addition, the framework analyzes the role that self-reported annoyance, and perception of noise levels, plays on the relationship between actual noise pressure levels and those decisions...
July 11, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28690825/white-crowned-sparrow-males-show-immediate-flexibility-in-song-amplitude-but-not-in-song-minimum-frequency-in-response-to-changes-in-noise-levels-in-the-field
#4
Elizabeth P Derryberry, Katherine Gentry, Graham E Derryberry, Jennifer N Phillips, Raymond M Danner, Julie E Danner, David A Luther
The soundscape acts as a selective agent on organisms that use acoustic signals to communicate. A number of studies document variation in structure, amplitude, or timing of signal production in correspondence with environmental noise levels thus supporting the hypothesis that organisms are changing their signaling behaviors to avoid masking. The time scale at which organisms respond is of particular interest. Signal structure may evolve across generations through processes such as cultural or genetic transmission...
July 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28687060/safety-limit-warning-levels-for-the-avoidance-of-excessive-sound-amplification-to-protect-against-further-hearing-loss
#5
Earl E Johnson
OBJECTIVE: To determine safe output sound pressure levels (SPL) for sound amplification devices to preserve hearing sensitivity after usage. DESIGN: A mathematical model consisting of the Modified Power Law (MPL) (Humes & Jesteadt, 1991 ) combined with equations for predicting temporary threshold shift (TTS) and subsequent permanent threshold shift (PTS) (Macrae, 1994b ) was used to determine safe output SPL. STUDY SAMPLE: The study involves no new human subject measurements of loudness tolerance or threshold shifts...
July 7, 2017: International Journal of Audiology
https://www.readbyqxmd.com/read/28679279/in-vivo-measurement-of-basilar-membrane-vibration-in-the-unopened-chinchilla-cochlea-using-high-frequency-ultrasound
#6
Thomas G Landry, Manohar L Bance, Jeffrey Leadbetter, Robert B Adamson, Jeremy A Brown
The basilar membrane and organ of Corti in the cochlea are essential for sound detection and frequency discrimination in normal hearing. There are currently no methods used for real-time high resolution clinical imaging or vibrometry of these structures. The ability to perform such imaging could aid in the diagnosis of some pathologies and advance understanding of the causes. It is demonstrated that high frequency ultrasound can be used to measure basilar membrane vibrations through the round window of chinchilla cochleas in vivo...
June 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28678697/in-ear-audio-wearable-measurement-of-heart-and-breathing-rates-for-health-and-safety-monitoring
#7
Alexis Martin, Jeremie Voix
OBJECTIVE: This paper examines the integration of a non-invasive vital sign monitoring feature into the workers' hearing protection devices (HPDs) by using a microphone positioned within the earcanal under the HPD. METHODS: 25 test-subjects were asked to breathe at various rhythms and intensities and these realistic sound events were recorded in the earcanal. Digital signal processing algorithms were then developed to assess heart and breathing rates. Finally, to test the robustness of theses algorithms in noisy work environments, industrial noise was added to the in-ear recorded signals and an adaptive denoising filter was used...
June 27, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28678077/high-frequency-distortion-product-otoacoustic-emission-repeatability-in-a-patient-population
#8
Laura Dreisbach, Erika Zettner, Margaret Chang Liu, Caitlin Meuel Fernhoff, Imola MacPhee, Arthur Boothroyd
OBJECTIVES: Distortion-product otoacoustic emissions (DPOAEs) are repeatable over time at lower frequencies (≤8 kHz) and higher frequencies (>8 kHz) in healthy, normal-hearing subjects. The purpose of this study was to examine the repeatability of DPOAEs measured with high-frequency (HF) stimuli in a patient population. It was hypothesized that HF DPOAEs would be repeatable over four trials. DESIGN: DPOAEs were measured in 40 cystic fibrosis (CF) patients (17 females and 23 males) with measurable behavioral thresholds and present DPOAEs for at least 2 of the high frequencies tested (8 to 16 kHz)...
July 1, 2017: Ear and Hearing
https://www.readbyqxmd.com/read/28650809/beam-diffraction-effects-in-the-backward-wave-regions-of-viscoelastic-leaky-lamb-modes-for-plate-transmission-at-normal-incidence
#9
Magne Aanes, Kjetil D Lohne, Per Lunde, Magne Vestrheim
Plane-wave theory for fluid-embedded isotropic plates is often used in ultrasonic guided-wave applications, and to estimate wall thickness, corrosion, or sound velocities in plates and pipes. In such structures, measured ultrasonic transmission through the solid material is affected by acoustic beam diffraction effects, and the results may deviate from plane-wave descriptions, which are insufficient to describe the complex effects that occur. When exciting a fluid-embedded steel plate with a pulsed ultrasonic beam at normal incidence, resonance frequency downshift, axial sound pressure level (SPL) increase, and beam narrowing have been observed, for measured resonance peaks in the frequency regions of certain leaky Lamb mode branches of the plate...
June 26, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28635402/analysing-the-vocal-behaviour-of-teachers-during-classroom-teaching-using-a-portable-voice-accumulator
#10
Manfred Nusseck, Bernhard Richter, Claudia Spahn, Matthias Echternach
PURPOSE: Teachers are at a considerable risk of developing vocal health problems due to intensive voice use during teaching. This study investigated factors related to the teacher's voice during a teaching situation. METHODS: Overall, 113 teachers were recorded during a typical class lesson, lasting on average 48 min. A portable voice dosimeter (VoxLog System) was used to measure the sound pressure level (SPL) of the noise in the classroom, the teacher's voice SPL, the fundamental frequency (fo) and the phonation time...
March 3, 2017: Logopedics, Phoniatrics, Vocology
https://www.readbyqxmd.com/read/28633809/extraction-of-olive-oil-assisted-by-high-frequency-ultrasound-standing-waves
#11
Pablo Juliano, Fabian Bainczyk, Piotr Swiergon, Made Ian Maheswara Supriyatna, Claudia Guillaume, Leandro Ravetti, Pablo Canamasas, Giancarlo Cravotto, Xin-Qing Xu
High-frequency ultrasound standing waves (megasonics) have been demonstrated to enhance oil separation in the palm oil process at an industrial level. This work investigated the application of megasonics in the olive oil process on laboratory and pilot scale levels. Sound pressure level and cavitational yield distribution were characterised with hydrophones and luminol to determine associated physical and sonochemical effects inside the reactor. The effect of water addition (0%, 15%, and 30%), megasonic power levels (0%, 50%, and 100%), and malaxation time (10min, 30min, and 50min) was evaluated using response surface methodology (RSM) in a 700g batch extraction process...
September 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28617326/a-study-on-the-model-of-detecting-the-liquid-level-of-sealed-containers-based-on-kirchhoff-approximation-theory
#12
Bin Zhang, Wen-Ai Song, Yue-Juan Wei, Dong-Song Zhang, Wen-Yi Liu
By simulating the sound field of a round piston transducer with the Kirchhoff integral theorem and analyzing the shape of ultrasound beams and propagation characteristics in a metal container wall, this study presents a model for calculating the echo sound pressure by using the Kirchhoff paraxial approximation theory, based on which and according to different ultrasonic impedance between gas and liquid media, a method for detecting the liquid level from outside of sealed containers is proposed. Then, the proposed method is evaluated through two groups of experiments...
June 15, 2017: Sensors
https://www.readbyqxmd.com/read/28615543/time-course-of-cell-death-due-to-acoustic-overstimulation-in-the-mouse-medial-geniculate-body-and-primary-auditory-cortex
#13
Felix Frohlich, Dietmar Basta, Ira Strübing, Arne Ernst, Moritz Gröschel
It has previously been shown that acoustic overstimulation induces cell death and extensive cell loss in key structures of the central auditory pathway. A correlation between noise-induced apoptosis and cell loss was hypothesized for the cochlear nucleus and colliculus inferior. To determine the role of cell death in noise-induced cell loss in thalamic and cortical structures, the present mouse study (NMRI strain) describes the time course following noise exposure of cell death mechanisms for the ventral medial geniculate body (vMGB), medial MGB (mMGB), and dorsal MGB (dMGB) and the six histological layers of the primary auditory cortex (AI 1-6)...
May 2017: Noise & Health
https://www.readbyqxmd.com/read/28605866/effect-of-temporary-open-air-markets-on-the-sound-environment-and-acoustic-perception-based-on-the-crowd-density-characteristics
#14
Qi Meng, Yang Sun, Jian Kang
The sound environment and acoustic perception of open-air markets, which are very common in high-density urban open spaces, play important roles in terms of the urban soundscape. Based on objective and subjective measurements of a typical temporary open-air market in Harbin city, China, the effects of the temporary open-air market on the sound environment and acoustic perception were studied, considering different crowd densities. It was observed that a temporary open-air market without zoning increases the sound pressure level and subjective loudness by 2...
June 8, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28601531/sheep-as-a-large-animal-ear-model-middle-ear-ossicular-velocities-and-intracochlear-sound-pressure
#15
Dominik Péus, Ivo Dobrev, Lukas Prochazka, Konrad Thoele, Adrian Dalbert, Andreas Boss, Nicolas Newcomb, Rudolf Probst, Christof Röösli, Jae Hoon Sim, Alexander Huber, Flurin Pfiffner
Animals are frequently used for the development and testing of new hearing devices. Dimensions of the middle ear and cochlea differ significantly between humans and commonly used animals, such as rodents or cats. The sheep cochlea is anatomically more like the human cochlea in size and number of turns. This study investigated the middle-ear ossicular velocities and intracochlear sound pressure (ICSP) in sheep temporal bones, with the aim of characterizing the sheep as an experimental model for implantable hearing devices...
August 2017: Hearing Research
https://www.readbyqxmd.com/read/28599539/the-effects-of-click-rate-on-the-auditory-brainstem-response-of-bottlenose-dolphins
#16
Robert F Burkard, James J Finneran, Jason Mulsow
Rate manipulations can be used to study adaptation processes in the auditory nerve and brainstem. For this reason, rate effects on the click-evoked auditory brainstem response (ABR) have been investigated in many mammals, including humans. In this study, click-evoked ABRs were obtained in eight bottlenose dolphins (Tursiops truncatus) while varying stimulus rate using both conventional averaging and maximum length sequences (MLSs), which allow disentangling ABRs that overlap in time and thus permit the study of adaptation at high rates...
May 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28599526/the-relation-between-psychoacoustical-factors-and-annoyance-under-different-noise-reduction-conditions-for-railway-noise
#17
Christian H Kasess, Thomas Maly, Piotr Majdak, Holger Waubke
The A-weighted sound pressure level (SPL) is commonly used to assess the effect of noise reduction measures on noise-induced annoyance. While for road traffic noise loudness seems to be a better descriptor of annoyance, for railway noise a systematic investigation seems to be lacking. Thus, in this study, the relation between annoyance and perceptually motivated descriptors was investigated for various conditions of binaural recordings of pass-bys of cargo and passenger trains. The conditions included free field and spectral mitigations caused by a 4 m high noise barrier, a 1 m high noise barrier close to the track, and rail dampers...
May 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28598950/drill-induced-cochlear-injury-during-otologic-surgery-intracochlear-pressure-evidence-of-acoustic-trauma
#18
Renee M Banakis Hartl, Jameson K Mattingly, Nathaniel T Greene, Nyssa F Farrell, Samuel P Gubbels, Daniel J Tollin
HYPOTHESIS: Drilling on the incus produces intracochlear pressure changes comparable to pressures created by high-intensity acoustic stimuli. BACKGROUND: New-onset sensorineural hearing loss (SNHL) following mastoid surgery can occur secondary to inadvertent drilling on the ossicular chain. To investigate this, we test the hypothesis that high sound pressure levels are generated when a high-speed drill contacts the incus. METHODS: Human cadaveric heads underwent mastoidectomy, and fiber-optic sensors were placed in scala tympani and vestibuli to measure intracochlear pressures (PIC)...
August 2017: Otology & Neurotology
https://www.readbyqxmd.com/read/28595255/pilot-electroacoustic-analyses-of-a-sample-of-direct-to-consumer-amplification-products
#19
Nicholas S Reed, Joshua Betz, Frank R Lin, Sara K Mamo
OBJECTIVE: Recent national initiatives from the White House and Institute of Medicine have focused on strategies to increase the accessibility and affordability of hearing loss treatment given the average cost of $4700 for bilateral hearing aids. More affordable direct-to-consumer hearing technologies are increasingly gaining recognition, but the performance of these devices has been poorly studied. We investigated the technical and electroacoustic capabilities of several direct-to-consumer hearing devices to inform otolaryngologists who may be asked by patients to comment on these devices...
July 2017: Otology & Neurotology
https://www.readbyqxmd.com/read/28593081/the-use-of-noise-dampening-mats-to-reduce-heavy-equipment-noise-exposures-in-construction
#20
Sabah Saleh, Susan Woskie, Anila Bello
The performance of sound barriers was evaluated to determine their technical effectiveness and practicality in reducing noise exposures to operating engineers in construction. Commercially purchased sound dampening mats (SDMats) were installed inside three heavy-equipment engine compartments. Sound pressure levels (SPLs) were measured before and after installing the SDMats while the equipment was on idle and full-throttle settings where it normally operates. SPLs inside the heavy-equipment operator cabs were significantly reduced by 5...
June 2017: Safety and Health At Work
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