keyword
MENU ▼
Read by QxMD icon Read
search

Sound pressure level

keyword
https://www.readbyqxmd.com/read/28433394/a-modelling-comparison-between-received-sound-levels-produced-by-a-marine-vibroseis-array-and-those-from-an-airgun-array-for-some-typical-seismic-survey-scenarios
#1
Alec J Duncan, Linda S Weilgart, Russell Leaper, Michael Jasny, Sharon Livermore
Marine Vibroseis (MV) may provide a marine seismic sound source that has less environmental impact than conventional airguns. Modelled sound levels from a realistic MV array and airgun array with similar downward energy at frequencies <100Hz were compared under three scenarios: shallow, deep, and slope. Changing the layout of the MV array's higher frequency sources reduced sound exposure levels (SELs) by 4dB. At 100m range this MV was 20dB lower in peak-to-peak sound pressure level vs. the airgun array, decreasing to 12dB lower at 5km, the maximum modelled range for peak levels...
April 19, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28426992/factors-affecting-sound-energy-absorbance-in-acute-otitis-media-model-of-chinchilla
#2
Xiying Guan, Thomas W Seale, Rong Z Gan
Acute otitis media (AOM) is a rapid-onset infection of the middle ear which results in middle ear pressure (MEP), middle ear effusion (MEE), and structural changes in middle ear tissues. Previous studies from our laboratory have identified that MEP, MEE, and middle ear structural changes are three factors affecting tympanic membrane (TM) mobility and hearing levels (Guan et al., 2014, 2013). Sound energy reflectance or absorbance (EA) is a diagnostic tool increasingly used in clinical settings for the identification of middle ear diseases...
April 10, 2017: Hearing Research
https://www.readbyqxmd.com/read/28414275/a-new-hypothesis-on-the-frequency-discrimination-of-the-cochlea
#3
Erdoğan Bulut, Cem Uzun, Levent Öztürk, Pınar Turan, Mehmet Kanter, Serap Arbak
OBJECTIVE: Medial olivocochlear efferent (MOCE) neurons innervate outer hair cells (OHCs) of the cochlea, which in turn leads to basilar membrane motion. We hypothesized that MOCE-induced alterations in basilar membrane motion, independent of traveling waves, is responsible for the cochlear frequency discrimination of sound. MATERIALS AND METHODS: Eleven guinea pigs underwent bilateral otoscopic and audiologic evaluations under general anesthesia. The study comprised two parts...
April 17, 2017: Journal of International Advanced Otology
https://www.readbyqxmd.com/read/28413332/fluid-dynamics-of-acoustic-and-hydrodynamic-cavitation-in-hydraulic-power-systems
#4
REVIEW
A Ferrari
Cavitation is the transition from a liquid to a vapour phase, due to a drop in pressure to the level of the vapour tension of the fluid. Two kinds of cavitation have been reviewed here: acoustic cavitation and hydrodynamic cavitation. As acoustic cavitation in engineering systems is related to the propagation of waves through a region subjected to liquid vaporization, the available expressions of the sound speed are discussed. One of the main effects of hydrodynamic cavitation in the nozzles and orifices of hydraulic power systems is a reduction in flow permeability...
March 2017: Proceedings. Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28403175/altered-cortical-and-subcortical-connectivity-due-to-infrasound-administered-near-the-hearing-threshold-evidence-from-fmri
#5
Markus Weichenberger, Martin Bauer, Robert Kühler, Johannes Hensel, Caroline Garcia Forlim, Albrecht Ihlenfeld, Bernd Ittermann, Jürgen Gallinat, Christian Koch, Simone Kühn
In the present study, the brain's response towards near- and supra-threshold infrasound (IS) stimulation (sound frequency < 20 Hz) was investigated under resting-state fMRI conditions. The study involved two consecutive sessions. In the first session, 14 healthy participants underwent a hearing threshold-as well as a categorical loudness scaling measurement in which the individual loudness perception for IS was assessed across different sound pressure levels (SPL). In the second session, these participants underwent three resting-state acquisitions, one without auditory stimulation (no-tone), one with a monaurally presented 12-Hz IS tone (near-threshold) and one with a similar tone above the individual hearing threshold corresponding to a 'medium loud' hearing sensation (supra-threshold)...
2017: PloS One
https://www.readbyqxmd.com/read/28401629/a-1-470%C3%A2-nm-diode-laser-in-stapedotomy-mechanical-thermal-and-acoustic-effects
#6
Simone P C Koenraads, Tjeerd de Boorder, Wilko Grolman, Digna M A Kamalski
BACKGROUND AND OBJECTIVES: Multiple laser systems have been investigated for their use in stapes surgery in patients with otosclerosis. The diode 1,470 nm laser used in this study is an attractive laser system because it is easily transported and relatively inexpensive in use. This wavelength has relative high absorption in water. This study aimed to investigate the mechanical, thermal, and acoustic effects of the diode 1,470 nm laser on a stapes in an inner ear model. MATERIALS AND METHODS: Experiments were performed in an inner ear model including fresh frozen human stapes...
April 11, 2017: Lasers in Surgery and Medicine
https://www.readbyqxmd.com/read/28392708/lung-sound-analysis-helps-localize-airway-inflammation-in-patients-with-bronchial-asthma
#7
Terufumi Shimoda, Yasushi Obase, Yukio Nagasaka, Hiroshi Nakano, Akiko Ishimatsu, Reiko Kishikawa, Tomoaki Iwanaga
PURPOSE: Airway inflammation can be detected by lung sound analysis (LSA) at a single point in the posterior lower lung field. We performed LSA at 7 points to examine whether the technique could identify the location of airway inflammation in patients with asthma. PATIENTS AND METHODS: Breath sounds were recorded at 7 points on the body surface of 22 asthmatic subjects. Inspiration sound pressure level (ISPL), expiration sound pressure level (ESPL), and the expiration-to-inspiration sound pressure ratio (E/I) were calculated in 6 frequency bands...
2017: Journal of Asthma and Allergy
https://www.readbyqxmd.com/read/28383463/influence-of-floating-mass-transducer-coupling-efficiency-for-active-middle-ear-implants-on-speech-recognition
#8
Alexander Müller, Parwis Mir-Salim, Nina Zellhuber, Ralf Helbig, Marc Bloching, Tobias Schmidt, Sven Koscielny, Oliver C Dziemba, Stefan K Plontke, Torsten Rahne
OBJECTIVE: The efficiency of vibroplasty (coupler-floating mass transducer [FMT] assembly) can be monitored by direct stimulation of the inner ear through the active middle-ear implant system and comparison of the vibroplasty in vivo threshold and the postoperative bone-conduction pure-tone threshold. The aim of this study was to compare the vibroplasty in vivo threshold with the postoperative speech recognition in patients with a high preoperative maximum word recognition score. STUDY DESIGN: Retrospective cohort study of German-speaking patients implanted with a vibrating ossicular prosthesis (VORP) 502 or VORP 503 and high preoperative maximum word recognition score between the years of 2011 and 2015...
April 5, 2017: Otology & Neurotology
https://www.readbyqxmd.com/read/28380260/a-numerical-study-of-the-acoustic-radiation-due-to-eddy-current-cryostat-interactions
#9
Yaohui Wang, Feng Liu, Xiaorong Zhou, Yu Li, Stuart Crozier
PURPOSE: To investigate the acoustic radiation due to eddy current-cryostat interactions and perform a qualitative analysis on noise reduction methods. METHODS: In order to evaluate the sound pressure level (SPL) of the eddy current induced warm bore wall vibration, a Finite Element (FE) model was created to simulate the noises from both the warm bore wall vibration and the gradient coil assembly. For the SPL reduction of the warm bore wall vibration, we first improved the active shielding of the gradient coil, thus reducing the eddy current on the warm bore wall...
April 5, 2017: Medical Physics
https://www.readbyqxmd.com/read/28378762/offshore-exposure-experiments-on-cuttlefish-indicate-received-sound-pressure-and-particle-motion-levels-associated-with-acoustic-trauma
#10
Marta Solé, Peter Sigray, Marc Lenoir, Mike van der Schaar, Emilia Lalander, Michel André
Recent findings on cephalopods in laboratory conditions showed that exposure to artificial noise had a direct consequence on the statocyst, sensory organs, which are responsible for their equilibrium and movements in the water column. The question remained about the contribution of the consequent near-field particle motion influence from the tank walls, to the triggering of the trauma. Offshore noise controlled exposure experiments (CEE) on common cuttlefish (Sepia officinalis), were conducted at three different depths and distances from the source and particle motion and sound pressure measurements were performed at each location...
April 5, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28372082/big-brown-bats-eptesicus-fuscus-maintain-hearing-sensitivity-after-exposure-to-intense-band-limited-noise
#11
Andrea Megela Simmons, Kelsey N Hom, James A Simmons
Thresholds to short-duration narrowband frequency-modulated (FM) sweeps were measured in six big brown bats (Eptesicus fuscus) in a two-alternative forced choice passive listening task before and after exposure to band-limited noise (lower and upper frequencies between 10 and 50 kHz, 1 h, 116-119 dB sound pressure level root mean square; sound exposure level 152 dB). At recovery time points of 2 and 5 min post-exposure, thresholds varied from -4 to +4 dB from pre-exposure threshold estimates. Thresholds after sham (control) exposures varied from -6 to +2 dB from pre-exposure estimates...
March 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28372073/fuselage-boundary-layer-refraction-of-fan-tones-radiated-from-an-installed-turbofan-aero-engine
#12
James Gaffney, Alan McAlpine, Michael J Kingan
A distributed source model to predict fan tone noise levels of an installed turbofan aero-engine is extended to include the refraction effects caused by the fuselage boundary layer. The model is a simple representation of an installed turbofan, where fan tones are represented in terms of spinning modes radiated from a semi-infinite circular duct, and the aircraft's fuselage is represented by an infinitely long, rigid cylinder. The distributed source is a disk, formed by integrating infinitesimal volume sources located on the intake duct termination...
March 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28372063/a-linearly-tapered-box-model-of-the-cochlea
#13
Guangjian Ni, Luyang Sun, Stephen J Elliott
A box shape with constant area is often used to represent the complex geometry in the cochlea, although variation of the fluid chambers areas is known to be more complicated. This variation is accounted for here by an "effective area," given by the harmonic mean of upper and lower chamber area from previous measurements. The square root of this effective area varies linearly along the cochleae in the investigated mammalian species. This suggests the use of a linearly tapered box model in which the fluid chamber width and height are equal, but decrease linearly along its length...
March 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28366808/calpain-inhibitor-alleviates-permanent-hearing-loss-induced-by-intense-noise-by-preventing-disruption-of-gap-junction-mediated-intercellular-communication-in-the-cochlear-spiral-ligament
#14
Taro Yamaguchi, Masanori Yoneyama, Kiyokazu Ogita
Our previous studies demonstrated that intense noise-induced hearing loss might be at least in part due to an oxidative stress-induced decrease in the level of gap junction-composing protein connexins in the spiral ligament (SL) of the cochlear lateral wall structures in mice. Further, an in vivo exposure of mice to intense noise activates calpain in the cochlear SL. Based on these studies, we sought to determine whether a calpain inhibitor would prevent an intense noise exposure from causing hearing loss, disruption of gap junction-mediated intercellular communication (GJIC) in the SL...
May 15, 2017: European Journal of Pharmacology
https://www.readbyqxmd.com/read/28356182/the-efficacy-of-low-level-continuous-positive-airway-pressure-for-the-treatment-of-snoring
#15
Michelle A Guzman, Francis P Sgambati, Huy Pho, Rafael S Arias, Erin M Hawks, Erica M Wolfe, Tamás Ötvös, Russell Rosenberg, Riad Dakheel, Hartmut Schneider, Jason P Kirkness, Philip L Smith, Alan R Schwartz
STUDY OBJECTIVES: To assess effects of low-level continuous positive airway pressure (CPAP) on snoring in habitual snorers without obstructive sleep apnea (OSA). METHODS: A multicenter prospective in-laboratory reversal crossover intervention trial was conducted between September 2013 and August 2014. Habitual snorers were included if they snored (inspiratory sound pressure level ≥ 40 dBA) for ≥ 30% all sleep breaths on a baseline sleep study (Night 1), and if significant OSA and daytime somnolence were absent...
February 19, 2017: Journal of Clinical Sleep Medicine: JCSM: Official Publication of the American Academy of Sleep Medicine
https://www.readbyqxmd.com/read/28348542/the-efficacy-of-short-term-gated-audiovisual-speech-training-for-improving-auditory-sentence-identification-in-noise-in-elderly-hearing-aid-users
#16
Shahram Moradi, Anna Wahlin, Mathias Hällgren, Jerker Rönnberg, Björn Lidestam
This study aimed to examine the efficacy and maintenance of short-term (one-session) gated audiovisual speech training for improving auditory sentence identification in noise in experienced elderly hearing-aid users. Twenty-five hearing aid users (16 men and 9 women), with an average age of 70.8 years, were randomly divided into an experimental (audiovisual training, n = 14) and a control (auditory training, n = 11) group. Participants underwent gated speech identification tasks comprising Swedish consonants and words presented at 65 dB sound pressure level with a 0 dB signal-to-noise ratio (steady-state broadband noise), in audiovisual or auditory-only training conditions...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/28339713/evaluation-of-the-effectiveness-of-intermittent-mechanical-pressure-with-short-loading-duration-new-type-of-intermittent-force-for-orthodontic-treatment
#17
Kento Shoman, Yoshiaki Sato, Eisuke Nishikawa, Yuusuke Kudo, Takaaki Yamamoto, Junichiro Iida
Background: Since it is difficult to precisely control the magnitude of force in orthodontic practice, controlling the duration of force is expected to prevent tissue damage. The use of an actuator as an appliance for intermittent force application is a possible solution for controlling the duration. However, effectiveness of an actuator for controlling the duration is still not clear. Aim: To determine whether a short loading duration of intermittent force has the potential to maintain a sound condition of the capillaries and induce dilation of capillaries, which is a requisite phenomenon for orthodontic tooth movement...
February 22, 2017: European Journal of Orthodontics
https://www.readbyqxmd.com/read/28335239/a-flexible-360-degree-thermal-sound-source-based-on-laser-induced-graphene
#18
Lu-Qi Tao, Ying Liu, Zhen-Yi Ju, He Tian, Qian-Yi Xie, Yi Yang, Tian-Ling Ren
A flexible sound source is essential in a whole flexible system. It's hard to integrate a conventional sound source based on a piezoelectric part into a whole flexible system. Moreover, the sound pressure from the back side of a sound source is usually weaker than that from the front side. With the help of direct laser writing (DLW) technology, the fabrication of a flexible 360-degree thermal sound source becomes possible. A 650-nm low-power laser was used to reduce the graphene oxide (GO). The stripped laser induced graphene thermal sound source was then attached to the surface of a cylindrical bottle so that it could emit sound in a 360-degree direction...
June 7, 2016: Nanomaterials
https://www.readbyqxmd.com/read/28329261/effects-of-noise-on-vascular-function-oxidative-stress-and-inflammation-mechanistic-insight-from-studies-in-mice
#19
Thomas Münzel, Andreas Daiber, Sebastian Steven, Lan P Tran, Elisabeth Ullmann, Sabine Kossmann, Frank P Schmidt, Matthias Oelze, Ning Xia, Huige Li, Antonio Pinto, Philipp Wild, Kai Pies, Erwin R Schmidt, Steffen Rapp, Swenja Kröller-Schön
Aims: Epidemiological studies indicate that traffic noise increases the incidence of coronary artery disease, hypertension and stroke. The underlying mechanisms remain largely unknown. Field studies with nighttime noise exposure demonstrate that aircraft noise leads to vascular dysfunction, which is markedly improved by vitamin C, suggesting a key role of oxidative stress in causing this phenomenon. Methods and results: We developed a novel animal model to study the vascular consequences of aircraft noise exposure...
February 17, 2017: European Heart Journal
https://www.readbyqxmd.com/read/28327081/pilot-study-of-patron-sound-level-exposure-in-loud-restaurants-bars-and-clubs-in-new-york-city
#20
Ariel Spira-Cohen, Anna Caffarelli, Lawrence Fung
Visiting restaurants, bars, clubs and lounges is a regular part of urban cultural life for residents and tourists alike; however, anecdotal reports and diner surveys suggest that sound levels are excessive and diners dislike them. High sound levels in these venues can contribute to both patron and employee overexposure, and young people may be particularly at risk. To supplement the paucity of literature and data on noise in urban venues, patron noise exposure was measured inside a sample of loud New York City (NYC) restaurants, bars, clubs and lounges...
March 22, 2017: Journal of Occupational and Environmental Hygiene
keyword
keyword
12065
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"