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https://www.readbyqxmd.com/read/28214051/effects-of-a-straw-phonation-protocol-on-acoustic-measures-of-an-satb-chorus-singing-two-contrasting-renaissance-works
#1
Jeremy N Manternach, Chad Clark, James F Daugherty
BACKGROUND: Researchers have found that semi-occluded vocal tract (SOVT) exercises may increase vocal economy by reducing phonation threshold pressure and effort while increasing or maintaining consistent acoustic output. This research has focused solely on individual singers. Much singing instruction, however, takes place in choral settings. Choral singers may use different resonance strategies or unconsciously adjust their singing based on the ability to hear their own sound in relation to others...
February 14, 2017: Journal of Voice: Official Journal of the Voice Foundation
https://www.readbyqxmd.com/read/28179167/mri-and-mrs-of-the-human-brain-at-magnetic-fields-of-14t-to-20t-technical-feasibility-safety-and-neuroscience-horizons
#2
Thomas F Budinger, Mark D Bird
The three goals of this paper are: 1) to evaluate the improvements in technology for increasing magnetic flux density (magnetic field) to 14T in the next few years and eventually to 20T; 2) to highlight neuroscience opportunities enabled by these advances; and, 3) to evaluate the physiological and biophysical effects associated with MRI at very high performance levels. Substantial recent advances in magnet technology including superconductor developments enable neuroscience goals that are not obtainable at contemporary magnetic fields...
February 4, 2017: NeuroImage
https://www.readbyqxmd.com/read/28166900/effects-of-auditory-and-tactile-warning-on-response-to-visual-hazards-under-a-noisy-environment
#3
Atsuo Murata, Takashi Kuroda, Waldemar Karwowski
A warning signal presented via a visual or an auditory cue might interfere with auditory or visual information inside and outside a vehicle. On the other hand, such interference would be certainly reduced if a tactile cue is used. Therefore, it is expected that tactile cues would be promising as warning signals, especially in a noisy environment. In order to determine the most suitable modality of cue (warning) to a visual hazard in noisy environments, auditory and tactile cues were examined in this study. The condition of stimulus onset asynchrony (SOA) was set to 0ms, 500ms, and 1000ms...
April 2017: Applied Ergonomics
https://www.readbyqxmd.com/read/28164935/effect-of-filters-on-the-noise-generated-by-continuous-positive-airway-pressure-delivered-via-a-helmet
#4
Ricardo Hernández-Molina, Francisco Fernández-Zacarías, Isabel Benavente-Fernández, Gema Jiménez-Gómez, Simón Lubián-López
INTRODUCTION: One of the problems that the delivery of continuous positive airway pressure (CPAP) via a helmet poses is the generation of noise. The objective of our study was to assess the effect that the use of filter has on sound pressure levels generated by the delivery of positive airway pressure at different gas flow rates. MATERIALS AND METHODS: Sound pressure levels generated by neonatal helmet CPAP delivery were measured at different gas flows (20, 30, and 40 l/min) with and without a breathing filter...
January 2017: Noise & Health
https://www.readbyqxmd.com/read/28163078/manganese-superoxide-dismutase-influences-the-extent-of-noise-induced-hearing-loss-in-mice
#5
Ayinuer Tuerdi, Makoto Kinoshita, Teru Kamogashira, Chisato Fujimoto, Shinnichi Iwasaki, Takahiko Shimizu, Tatsuya Yamasoba
Reactive oxygen species (ROS) generation is one of the mechanisms underlying noise-induced hearing loss (NIHL). Manganese superoxide dismutase (Mn-SOD), an antioxidant enzyme acting within the mitochondria, converts toxic superoxide to hydrogen peroxide. We investigated the role of Mn-SOD in NIHL by examining the extent of hearing loss and hair cell damage after noise exposure in C57BL/6 wild-type (WT) mice and Mn-SOD heterozygous knockout (HET) mice (n=6 each). Both HET and WT mice were exposed to 120dB sound pressure level at 4kHz octave band noise for 4h...
February 3, 2017: Neuroscience Letters
https://www.readbyqxmd.com/read/28147608/comparing-otoacoustic-emissions-evoked-by-chirp-transients-with-constant-absorbed-sound-power-and-constant-incident-pressure-magnitude
#6
Douglas H Keefe, M Patrick Feeney, Lisa L Hunter, Denis F Fitzpatrick
Human ear-canal properties of transient acoustic stimuli are contrasted that utilize measured ear-canal pressures in conjunction with measured acoustic pressure reflectance and admittance. These data are referenced to the tip of a probe snugly inserted into the ear canal. Promising procedures to calibrate across frequency include stimuli with controlled levels of incident pressure magnitude, absorbed sound power, and forward pressure magnitude. An equivalent pressure at the eardrum is calculated from these measured data using a transmission-line model of ear-canal acoustics parameterized by acoustically estimated ear-canal area at the probe tip and length between the probe tip and eardrum...
January 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28147604/large-region-acoustic-source-mapping-using-a-movable-array-and-sparse-covariance-fitting
#7
Shengkui Zhao, Cagdas Tuna, Thi Ngoc Tho Nguyen, Douglas L Jones
Large-region acoustic source mapping is important for city-scale noise monitoring. Approaches using a single-position measurement scheme to scan large regions using small arrays cannot provide clean acoustic source maps, while deploying large arrays spanning the entire region of interest is prohibitively expensive. A multiple-position measurement scheme is applied to scan large regions at multiple spatial positions using a movable array of small size. Based on the multiple-position measurement scheme, a sparse-constrained multiple-position vectorized covariance matrix fitting approach is presented...
January 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28147574/calibration-of-brief-stimuli-for-the-recording-of-evoked-responses-from-the-human-auditory-pathway
#8
Claus Elberling, Lau Crone Esmann
The relationship between the calibration RETSPL-values (reference equivalent threshold sound pressure level) in dB p-p.e.SPL and the corresponding sound pressure levels in dB SPL for brief stimuli is formulated mathematically. The formula is applied on ten brief stimuli consisting of a click, four tone-bursts, a chirp, and four octave-band chirps presented at a stimulus rate of 20 stimuli per second, and using the average acoustical parameter-values from a sample of 20 ER-3A insert earphones in the occluded-ear simulator...
January 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28147572/evaluation-of-optimal-masking-levels-in-place-specific-low-frequency-chirp-evoked-auditory-brainstem-responses
#9
Izet Baljić, Dirk Eßer, Astrid Foerst, Martin Walger
The aim of the study is the experimental determination of the optimal required masking level for a given stimulus level when using a band limited "low-frequency chirp" in order to improve frequency and place specificity of auditory brainstem responses (ABRs). A low-frequency chirp (100-850 Hz) at stimulation levels between 40 and 80 dB normalized hearing level was presented to 12 normal hearing subjects. During presentation of each stimulus, the level of a high-pass noise with a low cutoff frequency of 1100 Hz was varied between 0 and 25 dB signal-to-noise ratio (SNR) by using 5 dB steps (at 0 dB SNR the same level of both the chirp and the masker in dB sound pressure level was presented)...
January 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28147558/four-day-follow-up-study-on-the-voice-monitoring-of-primary-school-teachers-relationships-with-conversational-task-and-classroom-acoustics
#10
Giuseppina Emma Puglisi, Arianna Astolfi, Lady Catherine Cantor Cutiva, Alessio Carullo
The present study has investigated the occupational voice use of 27 female primary school teachers over a four-day-follow-up. Sixty-one working-day voice samples were acquired with two contact sensor-based vocal analyzers in four schools with highly different classroom acoustics. The vocal parameters were compared with a conversational task that the teachers performed before each lesson and with the measured classroom acoustic parameters. The average equivalent sound pressure level at 1 m from the mouth, which refers to the teacher's vocal effort, and the voicing time percentage were 71...
January 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28127654/-postoperative-wound-infections-diagnosis-classification-and-treatment
#11
D Seidel, J Bunse
BACKGROUND: Surgical site infections are a frequent complication of surgery and a severe burden for the patient as well as for the healthcare system. Sound knowledge of the disease pattern is an essential prerequisite for effective therapy. OBJECTIVE: This article presents an overview of the diagnosis, classification and treatment options for surgical site infections. MATERIAL AND METHODS: Based on the existing experience, the currently available evidence and pathophysiological considerations, an overview of the diagnostic possibilities, the existing classification systems and the treatment options is presented...
January 26, 2017: Der Chirurg; Zeitschrift Für Alle Gebiete der Operativen Medizen
https://www.readbyqxmd.com/read/28125319/fatigue-analysis-of-tympanic-membrane-after-ossiculoplasty
#12
Lei Zhou, Miaolin Feng, Xinsheng Huang, Maoli Duan
CONCLUSION: A tentative conclusion was made that the finite element method can be used to investigate the fatigue life of the tympanic membrane after ossiculoplasty; the main reason of the extrusion of the tympanic membrane may not be blamed to the fatigue mechanism under normal sound pressure. OBJECTIVE: This study was to investigate the extrusion of the prosthesis from the tympanic membrane at post-ossiculoplasty by finite element method. METHODS: A finite element model of the human middle ear has been constructed and used as the model of the constructed middle ear at post-ossiculoplasty...
January 26, 2017: Acta Oto-laryngologica
https://www.readbyqxmd.com/read/28116055/the-development-of-an-intermediate-duration-tag-to-characterize-the-diving-behavior-of-large-whales
#13
Bruce R Mate, Ladd M Irvine, Daniel M Palacios
The development of high-resolution archival tag technologies has revolutionized our understanding of diving behavior in marine taxa such as sharks, turtles, and seals during their wide-ranging movements. However, similar applications for large whales have lagged behind due to the difficulty of keeping tags on the animals for extended periods of time. Here, we present a novel configuration of a transdermally attached biologging device called the Advanced Dive Behavior (ADB) tag. The ADB tag contains sensors that record hydrostatic pressure, three-axis accelerometers, magnetometers, water temperature, and light level, all sampled at 1 Hz...
January 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28108153/parameters-from-the-complete-phonatory-range-of-an-excised-rabbit-larynx
#14
Randal D Mills, Keith Dodd, Alex Ablavsky, Erin Devine, Jack J Jiang
OBJECTIVE: This study aims to collect data throughout the complete phonatory range using rabbit larynges. STUDY DESIGN: This is a methodological excised rabbit larynx study. METHODS: Seven rabbit larynges were dissected and mounted on a modified excised laryngeal apparatus. Phonation was initiated at phonation threshold pressure (PTP) and airflow was increased by consistent increments until phonation instability pressure (PIP) was reached...
January 17, 2017: Journal of Voice: Official Journal of the Voice Foundation
https://www.readbyqxmd.com/read/28099168/a-non-invasive-approach-to-investigation-of-ventricular-blood-pressure-using-cardiac-sound-features
#15
Hong Tang, Jinghui Zhang, Huaming Chen, Ashok Mondal, Yongwan Park
Heart sounds (HSs) are produced by the interaction of the heart valves, great vessels, and heart wall with blood flow. Previous researchers have demonstrated that blood pressure can be predicted by exploring the features of cardiac sounds. These features include the amplitude of the HSs, the ratio of the amplitude, the systolic time interval, and the spectrum of the HSs. A single feature or combinations of several features have been used for prediction of blood pressure with moderate accuracy. Experiments were conducted with three beagles under various levels of blood pressure induced by different doses of epinephrine...
January 18, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28097504/estimating-the-relative-weights-of-visual-and-auditory-tau-versus-heuristic-based-cues-for-time-to-contact-judgments-in-realistic-familiar-scenes-by-older-and-younger-adults
#16
Behrang Keshavarz, Jennifer L Campos, Patricia R DeLucia, Daniel Oberfeld
Estimating time to contact (TTC) involves multiple sensory systems, including vision and audition. Previous findings suggested that the ratio of an object's instantaneous optical size/sound intensity to its instantaneous rate of change in optical size/sound intensity (τ) drives TTC judgments. Other evidence has shown that heuristic-based cues are used, including final optical size or final sound pressure level. Most previous studies have used decontextualized and unfamiliar stimuli (e.g., geometric shapes on a blank background)...
January 17, 2017: Attention, Perception & Psychophysics
https://www.readbyqxmd.com/read/28062201/effects-of-sound-pressure-level-and-visual-perceptual-load-on-the-auditory-mismatch-negativity
#17
Malina Szychowska, Rasmus Eklund, Mats E Nilsson, Stefan Wiens
Auditory change detection has been studied extensively with mismatch negativity (MMN), an event-related potential. Because it is unresolved if the duration MMN depends on sound pressure level (SPL), we studied effects of different SPLs (56, 66, and 76dB) on the duration MMN. Further, previous research suggests that the MMN is reduced by a concurrent visual task. Because a recent behavioral study found that high visual perceptual load strongly reduced detection sensitivity to irrelevant sounds, we studied if the duration MMN is reduced by load, and if this reduction is stronger at low SPLs...
January 3, 2017: Neuroscience Letters
https://www.readbyqxmd.com/read/28062093/resonance-tube-or-lax-vox
#18
Jaana Tyrmi, Vojtěch Radolf, Jaromír Horáček, Anne-Maria Laukkanen
OBJECTIVE: This study compares the flow resistance of Resonance tube (RT) and Lax Vox tube (LVT) when submerged 2 cm and 10 cm in water, as well as phonation into the tubes in these conditions. METHODS: In the in vitro experiment, the air pressure for flow rates of 60-600 mL/s was measured at the tube inlet, when the outer end of the tube was submerged 2 cm and 10 cm below water surface in 30°, 45°, and 90° angle. In the in vivo experiment, 14 subjects phonated in habitual loudness and loudly into both tubes, with the outer end 2 cm and 10 cm in water...
January 3, 2017: Journal of Voice: Official Journal of the Voice Foundation
https://www.readbyqxmd.com/read/28056335/effects-of-handling-and-environment-on-preterm-newborns-sleeping-in-incubators
#19
Kelly Cristina Sbampato Calado Orsi, Marta José Avena, Marcia Lurdes de Cacia Pradella-Hallinan, Mavilde da Luz Gonçalves Pedreira, Miriam Harumi Tsunemi, Ariane Ferreira Machado Avelar, Eliana Moreira Pinheiro
OBJECTIVE: To describe the total sleep time, stages of sleep, and wakefulness of preterm newborns and correlate them to levels of sound pressure, light, temperature, relative air humidity, and handling inside incubators. DESIGN: Observational, correlational study. SETTING: A neonatal intermediate care unit. PARTICIPANTS: Twelve preterm newborns, who were 32.2 ± 4.2 weeks gestational age and weighed 1,606 ± 317 g. METHODS: Sleep records were assessed by polysomnograph...
January 2, 2017: Journal of Obstetric, Gynecologic, and Neonatal Nursing: JOGNN
https://www.readbyqxmd.com/read/28056265/-a-cohort-study-on-occupational-noise-induced-hearing-loss-in-workers-at-an-iron-and-steel-plant
#20
S F Yu, G S Chen, J Jiao, G Z Gu, H L Zhang, X M Wang, W H Zhou, H Wu, Y H Li, Y X Zheng
Objective: To analyze the incidence rate of occupational noise-induced hearing loss in noise-exposed workers in an iron and steel plant from 2006 to 2015. Methods: Using a cohort study method, workers exposed to occupational noise from Jan 1, 2006 to Dec 12, 2015 were followed up and the pure tone hearing test was conducted. In total, 6 297 subjects completed two or more physical checks and the pure tone hearing test and were included in the analysis. The noise exposure level at the workplace and the equivalent continuous A-weighted sound pressure level for workers was monitored and the cumulative noise exposure dose was evaluated...
January 6, 2017: Zhonghua Yu Fang Yi Xue za Zhi [Chinese Journal of Preventive Medicine]
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