High sound pressure levels (>120dB) cause damage or death of the hair cells of the inner ear, hence causing hearing loss. Vocalization differences are present between hens and roosters. Crowing in roosters is reported to produce sound pressure levels of 100dB measured at a distance of 1m. In this study we measured the sound pressure levels that exist at the entrance of the outer ear canal. We hypothesize that roosters may benefit from a passive protective mechanism while hens do not require such a mechanism. Audio recordings at the level of the entrance of the outer ear canal of crowing roosters, made in this study, indeed show that a protective mechanism is needed as sound pressure levels can reach amplitudes of 142.3dB. Audio recordings made at varying distances from the crowing rooster show that at a distance of 0.5m sound pressure levels already drop to 102dB. Micro-CT scans of a rooster and chicken head show that in roosters the auditory canal closes when the beak is opened. In hens the diameter of the auditory canal only narrows but does not close completely. A morphological difference between the sexes in shape of a bursa-like slit which occurs in the outer ear canal causes the outer ear canal to close in roosters but not in hens.
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http://dx.doi.org/10.1016/j.zool.2017.12.002 | DOI Listing |
PeerJ
January 2025
Institute of Science and Environment, University of Saint Joseph, Macao, Macao S.A.R., China.
While soundscapes shape the structure and function of auditory systems over evolutionary timescales, there is limited information regarding the adaptation of wild fish populations to their natural acoustic environments. This is particularly relevant for freshwater ecosystems, which are extremely diverse and face escalating pressures from human activities and associated noise pollution. The Siamese fighting fish is one of the most important cultured species in the global ornamental fish market and is increasingly recognized as a model organism for genetics and behavioural studies.
View Article and Find Full Text PDFReports (MDPI)
December 2024
Division of Cardiology, Department of Medicine, University of Washington, Seattle, WA 98195, USA.
Unlabelled: The combination of hypertrophic cardiomyopathy with outflow tract obstruction, severe pre-capillary and post-capillary pulmonary hypertension, and severe primary mitral regurgitation is rare and presents distinct management challenges.
Background And Clinical Significance: Pulmonary hypertension is an independent predictor of all-cause mortality in patients with hypertrophic cardiomyopathy managed medically and often precludes patients from undergoing cardiopulmonary bypass due to increased surgical morbidity and mortality. In studies specifically evaluating surgical myectomy, however, survival is favorable in patients with moderate-to-severe pulmonary hypertension.
Sci Data
January 2025
ZheJiang Communications Investment Group Co., Ltd., ITS Branch, Hangzhou, 310000, China.
The subjective perceptions of passengers are intricately linked to the noise levels in subway stations of urban rail transit systems. In this study, comprehensive measurement was conducted on the noise environment on the platforms during operational hours at four distinct types of subway stations within an urban metro network. To ensure precise data collection, four different noise and sound pressure measurement points were strategically positioned in the middle and at both ends of each station platform.
View Article and Find Full Text PDFEmotion
January 2025
Department of Culture, Cognition and Computation, Interacting Minds Center, Aarhus University.
Crying in infancy is an important emotional signal that elicits care from adults, and women are often assumed to be more sensitive and reactive to infant crying than men. In a series of studies, we tested whether preparenthood gender differences in sensitivity to infant cries are a potential driver of the unequal share of early parenting. In Study 1, we tested for differences in men and women's awakening to infant crying and alarms among nonparents in an overnight experiment ( = 142).
View Article and Find Full Text PDFJ Acoust Soc Am
January 2025
Hangzhou Applied Acoustics Research Institute, Hangzhou, Zhejiang 311400, China.
To measure the electroacoustic parameters of transducers in the continuous sound field in a limited water area, a reciprocity calibration method of hydrophones using a spatial sampling average method in a non-anechoic tank was developed. The sound propagation in the non-anechoic tank under the impedance boundary condition, with a sound source producing continuous sound, is introduced based on the Helmholtz equation and Green's function. The reciprocity constant is given using the spatial sampling average sound pressure, and the three-transducer reciprocity calibration procedure was established.
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