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Sound pressure level

Kyoung-Ryul Lee, Sung Hwan Jang, Inhwa Jung
We investigated the acoustic performance of electrostatic sound-generating devices consisting of bilayer graphene on polyimide (PI) film. Total sound pressure level (SPL) of sound generated from the devices was measured as a function of source frequency by sweeping, and frequency spectra were measured at 1/3 octave band frequencies. The relationship between various operation conditions and total SPL was determined. In addition, the effects of changing voltage level, adding a DC offset, and using two pairs of electrodes were evaluated...
May 22, 2018: Nanotechnology
Alzbeta Pultznerova, Panulinova Eva, Daniela Kucharova, Lubica Argalasova
Introduction: This paper describes an assessment of noise caused by railway traffic in a large high-loaded railway track in Northwest Slovakia. Materials and Methods: The measurements of noise levels generated by trains passing through residential neighborhoods were taken. Noise maps were also calculated showing noise pollution generated by the train traffic. In addition, the annoyance level and sleep disturbance of residents affected by railway noise were evaluated by a validated questionnaire on a pilot sample of 107 respondents living near the important railway track...
May 2018: Noise & Health
Stephen Dance, Bradford Backus, Lorenzo Morales
Introduction: The effect of a sound reinforcement system, in terms of speech intelligibility, has been systematically determined under realistic conditions. Different combinations of ambient and reverberant conditions representative of a classroom environment have been investigated. Materials and Methods: By comparing the measured speech transmission index metric with and without the system in the same space under different room acoustics conditions, it was possible to determine when the system was most effective...
May 2018: Noise & Health
Olga N Milekhina, Dmitry I Nechaev, Alexander Ya Supin
The goal of the study was to assess cochlear compression when rippled-spectrum signals are perceived in noise assuming that the noise might produce both masking and confounding effects. In normal listeners, discrimination between rippled signals with and without ripple phase reversals was assessed in background noise. The signals were band-limited (0.5 oct at a - 6-dB level) rippled noise centered at 2 kHz, with a ripple density of 3.5 oct-1 . The noise (masker) was band-limited nonrippled noise centered at either 2 kHz (on-frequency masker) or 1 kHz (low-frequency masker)...
May 21, 2018: Journal of the Association for Research in Otolaryngology: JARO
Beat Schäffer, Reto Pieren, Sabine J Schlittmeier, Mark Brink
Environmental noise from transportation or industrial infrastructure typically has a broad frequency range. Different sources may have disparate acoustical characteristics, which may in turn affect noise annoyance. However, knowledge of the relative contribution of the different acoustical characteristics of broadband noise to annoyance is still scarce. In this study, the subjectively perceived short-term (acute) annoyance reactions to different broadband sounds (namely, realistic outdoor wind turbine and artificial, generic sounds) at 40 dBA were investigated in a controlled laboratory listening experiment...
May 19, 2018: International Journal of Environmental Research and Public Health
Christopher J Clark, Emily A Mistick
Wing trills are pulsed sounds produced by modified wing feathers at one or more specific points in time during a wingbeat. Male Allen's Hummingbird ( Selasphorus sasin ) produce a sexually dimorphic 9 kHz wing trill in flight. Here we investigate the kinematic basis for trill production. The wingtip velocity hypothesis posits that trill production is modulated by the airspeed of the wingtip at some point during the wingbeat, whereas the wing rotation hypothesis posits that trill production is instead modulated by wing rotation kinematics...
May 18, 2018: Journal of Experimental Biology
C Klein, C Wittmann, K N Wendt, C Ostgathe, S Stiel
BACKGROUND: Palliative sedation (PS) serves as a therapeutic option in cases of otherwise intractable suffering. As the use of sedative and hypnotic medication in many diverse situations is a core competency of anesthesiology, anesthesiologists are confronted with questions of sedative therapy at the end of life in institutions for specialized palliative care, in intensive care units and intermediate care wards. In recent years a number of guidelines have been published internationally but so far no official guidelines exist in Germany...
May 16, 2018: Der Anaesthesist
Ali E Aliev, Daniel Codoluto, Ray H Baughman, Raquel Ovalle-Robles, Kanzan Inoue, Stepan A Romanov, Albert Nasibulin, Prashant Kumar, Shashank Priya, Nathanael K Mayo, John Blottman
The combination of smooth, continuous sound spectra produced by a sound source having no vibrating parts, a nanoscale thickness of a flexible active layer and the feasibility of creating large, conformal projectors provoke interest in thermoacoustic phenomena. However, at low frequencies, the sound pressure level and the sound generation efficiency of open carbon nanotube sheets (CNTS) is low. In addition, the nanoscale thickness of fragile heating elements, their high sensitivity to the environment and the high surface temperatures practical for thermoacoustic sound generation necessitate a protective encapsulation of freestanding CNTS in inert gases...
May 15, 2018: Nanotechnology
Montserrat Pàmies-Vilà, Alex Hofmann, Vasileios Chatziioannou
Articulation on the clarinet is achieved by a combination of precise actions taking place inside the player's mouth. With the aim to analyse the effects of tonguing and blowing actions during playing, several physical variables are measured and parameters related to articulation are studied. Mouth pressure, mouthpiece pressure and reed displacement are recorded in an experiment with clarinet players to evaluate the influence of the player's actions on the selected parameters and on the sound. The results show that different combinations of tongue and blowing actions are used during performance...
2018: Frontiers in Psychology
Vitor Carneiro de Magalhães Tolentino, Camilla Queiroz Baesse, Celine de Melo
The structure and organization of acoustic signals arise through evolutionary processes and adaptive pressures on each species. During learning, natural or anthropogenic factors, such as high noise levels in urban areas, pose challenges to acoustic communication in birds. Many species adjust their acoustic signals to higher noise levels by increasing the frequency of vocalizations. The objectives of this study were to compare the dominant frequency of songs among birds dwelling in forest fragments distant from and near to urban areas, establish correlations between the dominant frequency of song and noise levels in these environments and verified the difference of response between oscines, suboscines and non-passerines...
April 2018: Environmental Pollution
Clae C Smull, Brandon Madsen, Robert H Margolis
OBJECTIVE: The Sennheiser HDA 200 earphone, a standard circumaural earphone used in audiometry for many years, is out of production and is replaced by the RadioEar DD450. The Sennheiser HD 280 Pro earphone is a consumer product that has characteristics that may be suitable for audiometry and may be a low-cost alternative to the DD450. The DD450 and HD 280 Pro earphones were compared with the HDA 200 for use in audiometry. DESIGN: RadioEar DD450 and Sennheiser HD 280 Pro earphones were evaluated for reference equivalent threshold sound pressure levels (RETSPLs), ambient-noise attenuation, and occlusion effects...
May 8, 2018: Ear and Hearing
Sriram Boothalingam, Julianne Kurke, Sumitrajit Dhar
There currently are no standardized protocols to evaluate auditory efferent function in humans. Typical tests use broadband noise to activate the efferents, but only test the contralateral efferent pathway, risk activating the middle ear muscle reflex (MEMR), and are laborious for clinical use. In an attempt to develop a clinical test of bilateral auditory efferent function, we have designed a method that uses clicks to evoke efferent activity, obtain click-evoked otoacoustic emissions (CEOAEs), and monitor MEMR...
May 7, 2018: Journal of the Association for Research in Otolaryngology: JARO
Yong-Ho Park, Juyong Chung, Min Young Lee, Doh Young Lee, Young Ho Kim
Objectives: To investigate how mouse cochleae are affected by the striking noise of titanium head golf driver. Methods: Thirty-two BALB/c mice (20-22 g) with normal hearing were used. The impact acoustic stimulus generated by the striking of titanium golf driver head was centered around 4.5 kHz with 120.5 dB sound pressure level. The recorded impact noise was provided to mice in two ways with the same exposure time of 288 seconds: 1,440 repetitions and an impact duration of 0...
May 3, 2018: Clinical and Experimental Otorhinolaryngology
Ronald A Kastelein, Lean Helder-Hoek, John M Terhune
High-amplitude impulsive sounds produced by pile driving and airguns may result in hearing damage in nearby seals. By swimming at the water surface, seals may reduce their exposure to underwater sound, as sound pressure levels (SPLs) are often lower just below the surface than deeper in the water column. Seals can make physiological adjustments such that they can switch between having maximum sensitivity for either aerial or underwater sounds. This could mean that hearing sensitivity for underwater sounds is lower when swimming at the water surface (when hearing may be focused on aerial sounds) than when swimming at depth...
April 2018: Journal of the Acoustical Society of America
Ishan S Bhatt
This study compared the effects of supra-aural and insert receivers on the prevalence of noise-induced hearing loss (NIHL) in young adults. NIHL prevalence was found to be substantially higher when hearing thresholds were obtained with supra-aural compared to insert receivers on the same subjects. Real-ear sound pressure levels at 4000, 6000, and 8000 Hz were the major predictors of notched-audiograms obtained with supra-aural headphones. Distortion-product otoacoustic emissions were not significantly different between ears with and without notched-audiograms obtained with supra-aural headphones...
April 2018: Journal of the Acoustical Society of America
Bin Yang, Eddie Wong, Wai Hong Ho, Condon Lau, Ying Shing Chan, Ed X Wu
Short duration and high intensity acoustic exposures can lead to temporary hearing loss and auditory nerve degeneration. This study investigates central auditory system function following such acute exposures after hearing loss recedes. Adult rats were exposed to 100 dB sound pressure level noise for 15 min. Auditory brainstem responses (ABRs) were recorded with click sounds to check hearing thresholds. Functional magnetic resonance imaging (fMRI) was performed with tonal stimulation at 12 and 20 kHz to investigate central auditory changes...
April 2018: Journal of the Acoustical Society of America
Gibbeum Kim, Woojae Han
BACKGROUND: The present study estimated the sound pressure levels of various music genres at the volume steps that contemporary smartphones deliver, because these levels put the listener at potential risk for hearing loss. METHODS: Using six different smartphones (Galaxy S6, Galaxy Note 3, iPhone 5S, iPhone 6, LG G2, and LG G3), the sound pressure levels for three genres of K-pop music (dance-pop, hip-hop, and pop-ballad) and a Billboard pop chart of assorted genres were measured through an earbud for the first risk volume that was at the risk sign proposed by the smartphones, as well as consecutive higher volumes using a sound level meter and artificial mastoid...
May 1, 2018: BMC Public Health
Gülay Altun Uğraş, Güven Yıldırım, Serpil Yüksel, Yusuf Öztürkçü, Mustafa Kuzdere, Seher Deniz Öztekin
OBJECTIVE: The purpose of this study was to determine effect of three different types of music on patients' preoperative anxiety. METHOD: This randomized controlled trial included 180 patients who were randomly divided into four groups. While the control group didn't listen to music, the experimental groups respectively listened to natural sounds, Classical Turkish or Western Music for 30 min. The State Anxiety Inventory (STAI-S), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and cortisol levels were checked...
May 2018: Complementary Therapies in Clinical Practice
Sun-Young Oh, Rainer Boegle, Matthias Ertl, Thomas Stephan, Marianne Dieterich
Multisensory convergence and sensorimotor integration are important aspects for the mediation of higher vestibular cognitive functions at the cortical level. In contrast to the integration of vestibulo-visual or vestibulo-tactile perception, much less is known about the neural mechanism that mediates the integration of vestibular-otolith (linear acceleration/translation/gravity detection) and auditory processing. Vestibular-otolith and auditory afferents can be simultaneously activated using loud sound pressure stimulation, which is routinely used for testing cervical and ocular vestibular evoked myogenic potentials (VEMPs) in clinical neurotological testing...
April 24, 2018: NeuroImage
Sergio Motta, Ugo Cesari, Mariano Paternoster, Giovanni Motta, Giuseppe Orefice
OBJECTIVE: To verify possible relations between vocal disability and aerodynamic measures in selected Parkinson's disease (PD) patients with low/moderate-grade dysphonia. METHODS: Fifteen idiopathic dysphonic PD male patients were examined and compared with 15 euphonic subjects. Testing included the following measures: Voice Handicap Index (VHI), maximum phonation time (MPT), mean estimated subglottal pressure (MESGP), mean sound pressure level (MSPL), mean phonatory power (MPP), mean phonatory efficiency (MPE) and mean phonatory resistance (MPR)...
April 23, 2018: European Archives of Oto-rhino-laryngology
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