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Sound pressure level

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
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
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
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
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
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...
June 7, 2017: Hearing Research
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
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
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)...
June 8, 2017: Otology & Neurotology
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
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
Jinhong Luo, Ninad B Kothari, Cynthia F Moss
Sensing is fundamental to the control of movement: From grasping objects to speech production, sensing guides action. So far, most of our knowledge about sensorimotor integration comes from visually guided reaching and oculomotor integration, in which the time course and trajectories of movements can be measured at a high temporal resolution. By contrast, production of vocalizations by humans and animals involves complex and variable actions, and each syllable often lasts a few hundreds of milliseconds, making it difficult to infer underlying neural processes...
June 20, 2017: Proceedings of the National Academy of Sciences of the United States of America
María Priscilla Portillo, Sandra Rojas, Marco Guzman, Camilo Quezada
PURPOSE: The present study aimed to observe whether physiological warm-up and traditional singing warm-up differently affect aerodynamic, electroglottographic, acoustic, and self-perceived parameters of voice in Contemporary Commercial Music singers. METHODS: Thirty subjects were asked to perform a 15-minute session of vocal warm-up. They were randomly assigned to one of two types of vocal warm-up: physiological (based on semi-occluded exercises) or traditional (singing warm-up based on open vowel [a:])...
May 31, 2017: Journal of Voice: Official Journal of the Voice Foundation
Maria Lúcia Vaz Masson, Tânia Maria de Araújo
OBJECTIVE: This study aimed to compare the effects of two protective strategies, voice amplification (VA) and 0.9% NaCl nebulization (NEB), on teachers' voice in the work setting. METHODS: An interventional evaluator-blind study was conducted, assigning 53 teachers from two public high schools to one of the two protective strategy groups (VA or NEB). Vocal function was assessed in a sound-treated booth before and after a 4-week period. Assessment included the severity of voice impairment (Consensus Auditory-Perceptual Evaluation of Voice [CAPE-V]), acoustic analysis of fundamental frequency (f0), sound pressure level (SPL), jitter, shimmer, glottal-to-noise excitation ratio (GNE), noise (VoxMetria), and the self-rated Screening Index for Voice Disorder (SIVD)...
May 31, 2017: Journal of Voice: Official Journal of the Voice Foundation
Anne K Maxwell, Renee M Banakis Hartl, Nathaniel T Greene, Victor Benichoux, Jameson K Mattingly, Stephen P Cass, Daniel J Tollin
HYPOTHESIS: Acoustic stimulation generates measurable sound pressure levels in the semicircular canals. BACKGROUND: High-intensity acoustic stimuli can cause hearing loss and balance disruptions. To examine the propagation of acoustic stimuli to the vestibular end-organs, we simultaneously measured fluid pressure in the cochlea and semicircular canals during both air- and bone-conducted sound presentation. METHODS: Five full-cephalic human cadaveric heads were prepared bilaterally with a mastoidectomy and extended facial recess...
May 31, 2017: Otology & Neurotology
Reinhard Müller, Joachim Schneider
OBJECTIVE: The cockpit workplace of airline pilots is a noisy environment. This study examines the hearing thresholds of pilots with respect to ambient noise and communication sound. METHODS: The hearing of 487 German pilots was analysed by audiometry in the frequency range of 125 Hz-16 kHz in varying age groups. Cockpit noise (free-field) data and communication sound (acoustic manikin) measurements were evaluated. RESULTS: The ambient noise levels in cockpits were found to be between 74 and 80 dB(A), and the sound pressure levels under the headset were found to be between 84 and 88 dB(A)...
May 30, 2017: BMJ Open
Kendrich Graemer Ong Tan
OBJECTIVES: The present study aimed to investigate the contact quotient (CQ) values of breathy, normal, and pressed phonation types in four different sections of the female singing range. METHODS: Electroglottography (EGG) and acoustic signals were recorded from 10 female singing teachers. Five vowels were sung for 1-3 seconds each, in three phonation types-normal, breathy, and pressed, in four pitches representing registration change points in the singing range...
May 26, 2017: Journal of Voice: Official Journal of the Voice Foundation
Vinaya Manchaiah, Brian Taylor, Ashley L Dockens, Nicole R Tran, Kayla Lane, Mariana Castle, Vibhu Grover
BACKGROUND: This systematic literature review is aimed at investigating applications of direct-to-consumer hearing devices for adults with hearing loss. This review discusses three categories of direct-to-consumer hearing devices: 1) personal sound amplification products (PSAPs), 2) direct-mail hearing aids, and 3) over-the-counter (OTC) hearing aids. METHOD: A literature review was conducted using EBSCOhost and included the databases CINAHL, MEDLINE, and PsycINFO...
2017: Clinical Interventions in Aging
Annika Szabo Portela, Svante Granqvist, Sten Ternström, Maria Södersten
OBJECTIVES: This study aimed to assess vocal behavior in women with voice-intensive occupations to investigate differences between patients and controls and between work and leisure conditions with environmental noise level as an experimental factor. METHODS: Patients with work-related voice disorders, 10 with phonasthenia and 10 with vocal nodules, were matched regarding age, profession, and workplace with 20 vocally healthy colleagues. The sound pressure level of environmental noise and the speakers' voice, fundamental frequency, and phonation ratio were registered from morning to night during 1 week with a voice accumulator...
May 24, 2017: Journal of Voice: Official Journal of the Voice Foundation
Nobuyuki Takeuchi, Shunsuke Sugiyama, Koji Inui, Kousuke Kanemoto, Makoto Nishihara
Sensory gating is a mechanism of sensory processing used to prevent an overflow of irrelevant information, with some indexes, such as prepulse inhibition (PPI) and P50 suppression, often utilized for its evaluation. In addition, those are clinically important for diseases such as schizophrenia. In the present study, we investigated long-latency paired-pulse suppression of change-related cortical responses using magnetoencephalography. The test change-related response was evoked by an abrupt increase in sound pressure by 15 dB in a continuous sound composed of a train of 25-ms pure tones at 65 dB...
2017: PloS One
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