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Joyce William W Zoophysiology, Department of Biosciences, Aarhus University, DK-8000 Aarhus C, Denmark. Electronic address: - - 2014
Few studies have investigated adenosinergic regulation of the cardiovascular system in reptiles. The haemodynamic effect of a bolus intra-arterial adenosine injection (2.5μMkg(-1)) was investigated in nine anaesthetised red-eared sliders (Trachemys scripta). Adenosine caused a transient bradycardia, which was accompanied by systemic vasodilatation as evidenced by an increase in systemic flow ...
Csakanyi Zsuzsanna Z *Department of Pediatric Otorhinolaryngology, Heim Pal Children's Hospital, 13 Delej utca, H-1089 Budapest, Hungary; †Budapest University of Technology and Economics, 3-9 Műegyetem rkp, H-1111 Budapest, Hungary; ‡Faculty of Engineering, University of Szeged, 13 Dugonics square, H-6720 Szeged, Hungary; and §Department of Otorhinolaryngology and Head and Neck Surgery, Health Science Centre, University of Debrecen, 98 Nagyerdei krt., H-4032 Debrecen, - - 2014
To establish a mathematical model of middle ear gas pressure regulation and to discuss potential implications for pathophysiology-oriented theoretical approach to middle ear surgery, with particular attention to mastoid obliteration. Numerous studies support that small mastoid volume is associated with cholesteatoma. Latest studies show that mastoid obliteration is an effective ...
Bergevin Christopher C Department of Physics & Astronomy, York University, Toronto, Ontario M3J1P3, - - 2014
Sound energy is conveyed to the inner ear by the diaphanous, cone-shaped tympanic membrane (TM). The TM moves in a complex manner and transmits sound signals to the inner ear with high fidelity, pressure gain, and a short delay. Miniaturized sensors allowing high spatial resolution in small spaces and sensitivity ...
Lynch James H JH 1Primary Care Sports Medicine, Special Operations Command Africa, Stuttgart, Germany; and 2Emergency Medicine Residency, Naval Medical Center, San Diego, - - 2014
The human body is well adapted to dealing with small variations in atmospheric pressure. However when our pursuit of sport and recreation takes us to extreme altitudes or ocean depths, the change in surrounding pressure has the potential to cause significant morbidity. Sports with more extreme changes in atmospheric pressure ...
Massey E Wayne EW Department of Neurology, Duke University Medical Center, Durham, NC, USA. Electronic address: - - 2014
Diving exposes a person to the combined effects of increased ambient pressure and immersion. The reduction in pressure when surfacing can precipitate decompression sickness (DCS), caused by bubble formation within tissues due to inert gas supersaturation. Arterial gas embolism (AGE) can also occur due to pulmonary barotrauma as a result ...
Wear Keith - - 2014
The traditional method for calculating acoustic pressure amplitude is to divide a hydrophone output voltage measurement by the hydrophone sensitivity at the acoustic working frequency, but this approach neglects frequency dependence of hydrophone sensitivity. Another method is to perform a complex deconvolution between the hydrophone output waveform and the hydrophone ...
Weddell Thomas D TD School of Pharmacy and Biomolecular Sciences, University of Brighton, , Brighton BN2 4GJ, - - 2014
The round window (RW) membrane provides pressure relief when the cochlea is excited by sound. Here, we report measurements of cochlear function from guinea pigs when the cochlea was stimulated at acoustic frequencies by movements of a miniature magnet which partially occluded the RW. Maximum cochlear sensitivity, corresponding to subnanometre ...
Ono Kanako K Graduate School of Medicine, Epidemiology and Public Health - - 2014
Abstract We investigated the relationship among 24-h blood pressure (BP), pulse rate (PR) and core temperature by using an ambulatory BP monitoring, a new wristwatch-type pulsimeter with accelerometer (WPA) and an ear thermometer simultaneously. Our results suggest that the ear temperature which reflects the core body temperature was lowest at ...
Santos Izabella Dos ID Universidade Estadual de Campinas, CampinasSP, Brasil, Aprimoramento em Saúde Auditiva, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, - - 2014
Introduction: The use of Personal Digital Audio Players can cause hearing injuries, as the sound is generated directly in the ear canal. It is believed that different types of headphones can cause different amplifications, since they cause changes in the volume and resonance of the ear canal according to their ...
Song Soohwa S aDepartment of Biomedical Engineering, Hanyang University, Seoul bDepartment of Biomedical Engineering, University of Ulsan, Ulsan, - - 2013
The auscultatory method is influenced by the hearing level of the observers. If the observer has hearing loss, it is possible to measure blood pressure inaccurately by misreading the Korotkoff sounds at systolic blood pressure (SBP) and diastolic blood pressure (DBP). Because of the potential clinical problems this discrepancy may ...
Zou Jing - - 2013
To elucidate the communication between the middle and inner ear, and the fluid dynamics of the inner ear with the perilymphatic fistula (PLF) of the round window membrane (RWM). The PLF of the RWM was created in nine guinea pigs. Gadolinium diethylenetriamine pentaacetic acid bismethylamide (Gd-DTPA-BMA) was delivered into the ...
Poulsen Torben T Department of Electrical Engineering, Technical University of Denmark , Lyngby , - - 2013
The main results in Poulsen & Oakley (2009) are given as the equivalent threshold sound pressure level, ETSPL, measured in an acoustic coupler specified in IEC 60318-3. These results are all correct. The ETSPL values for the ear simulator specified in IEC 60318-1 were calculated from acoustic laboratory measurements and ...
Foster C A - - 2013
We believe Meniere attacks arise as a chance association of endolymphatic hydrops and vascular risk factors for intracerebral ischemia. Hydrops acts as a variable Starling resistor upon the inner ear vasculature that is capable of inducing ischemic attacks only in people with reduced perfusion pressure in the ear. The unique ...
Duger Cevdet - - 2013
Objective: The aim of the present study was to compare the effects of two inhalation anesthetics, desflurane and sevoflurane, on middle ear pressure. Methods: After we obtained written consent from the patients and the approval from our institutional ethical committee, we included 56 ASA I-II patients aged between 18 and ...
Ravicz Michael E - - 2013
The transfer function HV between stapes velocity VS and sound pressure near the tympanic membrane PTM is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from ...
Feder Katya - - 2013
Objective: To examine the relationship between portable digital audio player listening behaviours and (1) measured sound pressure levels, (2) audiometric measures, (3) self-reported hearing loss symptoms. Design: A questionnaire to evaluate listening behaviours, including self-reported hearing loss symptoms and listening duration/volume settings. Multivariate regression analysis was used to determine the ...
Torija Antonio J - - 2013
A subjective and physical categorization of an ambient sound is the first step to evaluate the soundscape and provides a basis for designing or adapting this ambient sound to match people's expectations. For this reason, the main goal of this work is to develop a categorization and differentiation analysis of ...
Shaver Mark D - - 2013
The wideband energy reflectance (ER) technique has become popular as a tool for evaluating middle ear function. Negative middle ear pressure (MEP) is a prevalent form of middle ear dysfunction, which may impact application of ER measurements in differential diagnosis. A negative MEP may be countervailed by application of an ...
Brown D J - - 2013
Various theories suggest endolymphatic hydrops may cause a rupture of the membranous labyrinth or may force open the utriculo-saccular duct, resulting in a sudden change in inner ear function. Here, we have used slow injections of artificial endolymph into either scala media or the utricle of anaesthetised guinea pigs to ...
Silverman Carol A - - 2013
We describe tympanic membrane displacement (TMD) testing for non-invasive estimation of intracranial pressure (ICP). With the TMD test, displacement of the tympanic membrane of the middle ear is recorded during elicitation of the acoustic middle-ear reflex (AR). Increased intracranial/perilymphatic pressure displaces the resting stapes footplate laterally so that TMD during ...
Sleifer Pricila - - 2013
OBJECTIVE:To verify the levels of sound pressure emitted by non-certified children's toys. Cross-sectional study of sound toys available at popular retail stores of the so-called informal sector. Electronic, mechanical, and musical toys were analyzed. The measurement of each product was carried out by an acoustic engineer in an acoustically isolated ...
Taller Daniel - - 2013
The exponentially decaying acoustic pressure of scattered surface acoustic waves (SAWs) at the contact line of a liquid film pinned to filter paper is shown to sustain a high curvature conic tip with micron-sized modulations whose dimension grows exponentially from the tip. The large negative capillary pressure in the film, ...
Gauthier Marianne - - 2013
For the first time, and using an acoustical method, it has been shown experimentally that the inertial cavitation threshold pressure of an albumin-shelled microbubble is significantly correlated with its initial size.
van Dijk Pim - - 2013
Small changes of air pressure outside the eardrum of five lizard species led to changes in frequency, level, and peak width of spontaneous otoacoustic emissions (SOAE). In contrast to humans, these changes generally occurred at very small pressures (<20 mbar). As in humans, SOAE amplitudes were generally reduced. Changes of ...
Sivri Bekir - - 2013
OBJECTIVES/HYPOTHESIS: To investigate the effect of continuous positive airway pressure (CPAP) on middle ear pressure in patients with obstructive sleep apnea syndrome (OSAS). STUDY DESIGN: Prospective clinical case-control study. METHODS: Seventy-eight patients with moderate and severe OSAS (the mean apnea-hypopnea indexes were 22.70 ± 3.59 and 48.59 ± 12.50, respectively) ...
Li Lieber Po-Hung - - 2013
OBJECTIVES/HYPOTHESIS: Sound pressure level delivered through personal listening devices (PLDs) and reaching the ear drum might be affected by body size and jaw movements. This study aimed to investigate whether jaw movement and/or smaller body mass index (BMI) resulted in decrease of sound pressure level within the ear canals of ...
Zebian Makram - - 2013
The purpose of this study was to quantify the change in distortion product otoacoustic emission (DPOAE) level upon ear canal pressurization. DPOAEs were measured on 12 normal-hearing human subjects for ear canal static pressures between -200 and +200 daPa in (50 ± 5) daPa steps. A clear dependence of DPOAE levels on ...
Ravicz Michael E ME Eaton-Peabody Laboratory, Massachusetts Eye & Ear Infirmary, 243 Charles Street, Boston, Massachusetts 02114, USA. - - 2013
The middle-ear pressure gain GMEP, the ratio of sound pressure in the cochlear vestibule PV to sound pressure at the tympanic membrane PTM, is a descriptor of middle-ear sound transfer and the cochlear input for a given stimulus in the ear canal. GMEP and the cochlear partition differential pressure near ...
Cros Olivier - - 2013
The mastoid air cell system has traditionally been considered a passive role in gas exchange and pressure regulation the middle ear possibly with some acoustic function. However, more evidence has focused on the mucosa of the mastoid, which may play a more active role in regulation of middle ear pressure. ...
Guan Xiying - - 2013
Acute otitis media (AOM) is a rapid infection of middle ear due to bacterial or viral invasion. The infection commonly leads to negative pressure and purulent effusion in the middle ear. To identify how these changes affect tympanic membrane (TM) mobility or sound transmission through the middle ear, we hypothesize ...
Schulz Steffen - - 2013
Previous studies have proposed varying causes for idiopathic sudden sensorineural hearing loss (SSNHL), including vascular occlusion, ruptured inner ear membrane, acoustic tumours and circulatory disturbances in the inner ear. The objective of this study was to characterise the autonomic regulation in 19 SSNHL patients in comparison to 19 healthy age-gender ...
Agarwal Saurabh S Department of ENT and Head and Neck Surgery, Grant Medical College, J.J. Hospital, Room No. 712, Byculla, Mumbai, 400 008 - - 2013
To determine the likely association between hypertension and hearing loss. 150 cases and 124 controls, both genders, aged 45-64, included in the research after sample estimation. Hypertension was verified through blood pressure readings and was classified as grade 1, grade 2 and grade 3 hypertension or no hypertension according to ...
Maxwell Adam D AD Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA. - - 2013
In this study, the negative pressure values at which inertial cavitation consistently occurs in response to a single, two-cycle, focused ultrasound pulse were measured in several media relevant to cavitation-based ultrasound therapy. The pulse was focused into a chamber containing one of the media, which included liquids, tissue-mimicking materials, and ...
Sun Xiao-Ming - - 2013
Objective: To test the assumptions concerning the compensation of middle ear pressure (MEP) in using peak Y(tm) and the tympanogram asymmetry phenomenon, and to address the variability and reliability of 226 Hz tympanometry under negative MEP. Design: (1) Repeated measures in normal ears with experimentally-induced negative MEP; (2) Retrospective analysis ...
Yamada Shinichiro - - 2013
A 51-year-old woman was admitted to our hospital because of the right ear fullness and orthostatic headache. Based on the findings of low cerebrospinal fluid (CSF) pressure and detected images of CSF leakage by MRI myelography and radionuclide cisternography, she was diagnosed as having spontaneous intracranial hypotension (SIH). Audiograms in ...
Apan A - - 2013
The aim of this study was to investigate the effects of N2O-O2 mixture (Inspired O2 30%) on middle ear pressure (MEP) in children compared with the effects of an air-oxygen mixture (Inspired O2 50%). The study included thirty child patients who underwent general anaesthesia for different reasons, with the exception ...
Wilson Maria - - 2013
Toothed whales and bats have independently evolved biosonar systems to navigate and locate and catch prey. Such active sensing allows them to operate in darkness, but with the potential cost of warning prey by the emission of intense ultrasonic signals. At least six orders of nocturnal insects have independently evolved ...
Kimitsuki Takashi T Department of Otolaryngology, Kyushu Central Hospital, Shiobaru, Minami-ku, Fukuoka, Japan, - - 2013
An increase in hydrostatic pressure in the endolymphatic system causes hydrops-related inner ear diseases such as Meniere's disease or low tone sensorineural hearing loss. In the present study, we investigated the effects of pressure exerted on potassium currents in acutely isolated inner hair cells of the guinea-pig cochlea using whole-cell ...
Degerli Semih S Anaesthesiology Reanimation Clinic, Kecioren Training and Research Hospital Ankara, - - 2013
The procedure of laryngoscopic orotracheal intubation (LOTI) has many impacts on several parts of the body. But its effect on middle ear pressure (MEP) is not known well. The purpose of this study is to evaluate the MEP changes subsequent to insertion of endotracheal tube with laryngoscope. 44 patients were ...
Luan Ying - - 2012
A comparison between phospholipid-coated microbubbles with and without liposomes attached to the microbubble surface was performed using the ultra-high-speed imaging camera (Brandaris 128). We investigated 73 liposome-loaded microbubbles (loaded microbubbles) and 41 microbubbles without liposome loading (unloaded microbubbles) with a diameter ranging from 3-10 μm at frequencies ranging from 0.6-3.8 ...
Stieger Christof - - 2012
The cochlea is normally driven with "forward" stimulation, in which sound is introduced to the ear canal. Alternatively, the cochlea can be stimulated at the round window (RW) using an actuator. During RW "reverse" stimulation, the acoustic flow starting at the RW does not necessarily take the same path as ...
Shen Fanyi - - 2012
There are different opinions of the dynamics of an air bubble entering a xylem conduit. In this paper, we present a thorough mechanical analysis and conclude that there are three types of cavitation caused by air seeding. After an air seed enters a conduit at high xylem pressure , along ...
Larae Recker Karrie - - 2012
Background: Sound pressure-based real ear measurements are considered best practice for ensuring audibility among individuals fitting hearing aids. The accuracy of current methods is generally considered clinically acceptable for frequencies up to about 4 kHz. Recent interest in the potential benefits of higher frequencies has brought about a need for ...
Qian Wei - - 2012
ABSTRACTObjective:A novel method was employed to control the sternocleidomastoid muscle contraction level during vestibular evoked myogenic potential (VEMP) measurement.Study Design:A prospective study to measure the normal VEMP response.Settings:A pressure feedback device composed of a firm rubber bulb and a pressure gauge was employed to monitor the muscular contraction level during ...
Park Jonas J-H - - 2012
The influence of Eustachian tube (ET) dysfunction on the inner ear fluid pressure and thus on the inner ear function in Meniere's disease has been discussed controversially. So far, most of the studies examining ET function in inner ear disorders indirectly analyzed ET function by tympanometric methods. The present study ...
Sturtevant Blake T - - 2012
Acoustic imaging systems based on the parametric array concept utilize a nonlinear medium for mixing high frequency sound into a beam of low frequency collimated sound. Fluorocarbon fluids are very appealing as nonlinear mixing media with values of the nonlinearity parameter, B/A, typically greater than 10 at ambient temperature and ...
Stanzial Domenico - - 2012
Wide band p-v tympanometry can be defined as the measurement of the acoustic immittance of the ear, possibly in normal air pressure condition of the ear canal, and in the full audio frequency range. The most important innovation pioneered by the p-v tympanometry regards the introduction of a different principle ...
Jennings Amy - - 2012
BACKGROUND: Although a high intake of some flavonoid subclasses may reduce cardiovascular disease mortality, data regarding the in vivo mechanisms of action are limited. OBJECTIVE: We examined associations between habitual flavonoid intakes and direct measures of arterial stiffness, central blood pressure, and atherosclerosis. DESIGN: In a cross-sectional study of 1898 ...
Jones Erika S W - - 2012
The epithelial sodium channel (ENaC) may be a common underlying pathway for the development of primary hypertension. In South Africa, the R563Q variant of the ENaC is associated with low-renin-low-aldosterone hypertension and preeclampsia in black Africans and mixed-ancestry peoples. The purpose of this study was to investigate the prevalence of ...
Tsai Dai-Hua - - 2012
Short-term exposure to ambient particulate matter with aerodynamic diameters <10 μm were found to be positively associated with blood pressure. Yet, little information exists regarding the association between particles and circadian rhythm of blood pressure. Hence, we analyzed the association of exposure to particulate matter with aerodynamic diameters <10 μm ...
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