Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 13.135
Filtrar
1.
Appl Ergon ; 99: 103609, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34700191

RESUMO

When more than one audible alarm is heard simultaneously, discrimination may be compromised. This experiment compares near-simultaneous clinical alarms in two styles, the first are the tonal 'melodies' from the 2012/2006 version of a global medical device safety standard (IEC 60601-1-8) and the second are the auditory-icon-style recommended in the 2020 version of the same standard. Sixty-six participants were required to identify the meaning and priority of four different clinical alarms for one of the two styles of alarm (between-subjects). Alarms sounded both singly and in pairs (within-subjects). Results showed that the auditory icon alarms outperformed the tonal alarms on all measures except one, both for overall accuracy (recognizing both priority and function) and for partial accuracy (recognizing priority or function but not both). The results add to the growing body of evidence supporting the use of auditory icon alarms in clinical environments.


Assuntos
Alarmes Clínicos , Humanos , Monitorização Fisiológica , Som
2.
Sci Total Environ ; 802: 149869, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461470

RESUMO

The ratio of the perceived extent of natural sounds to the perceived extent of traffic noise in the environment has been demonstrated to be important for soundscapes, whereas research on the influence of human sounds has been limited. To examine this influence, this study proposes a human sound-based index named the red soundscape index (RSI), which is defined as the ratio of the perceived extent of human sounds to the perceived extent of other sounds. Sound pressure levels and crowd density were collected at 41 sites in 9 urban parks, and pedestrian streets in Harbin, China, and the perceived extent of various sounds was investigated by a questionnaire survey. The results confirmed a significant positive correlation between crowd density and RSI, and the A-weighted sound pressure level increased linearly with increasing RSIn (the ratio of human sounds to natural sounds) and decreased with increasing RSIt (the ratio of human sounds to traffic noises). Interestingly, the overall soundscape assessment linearly decreases with the increase in RSIn in the range of (0.8-1.5). The relationship with RSIt first shows an increase and then a decrease in a parabolic form, in which the axis of symmetry is RSIt = 2. Correspondingly, urban open spaces can be divided into three categories based on the variation trend, and different types have significant differences in overall soundscape assessment, pleasantness, and calmness. Among these, pleasantness is the highest in the sites of natural sound predominance perception. At the same time, this factor becomes the lowest in the sites of human sound predominance perception and middle in the site of balanced perception. Consequently, RSI is expected to be useful in soundscape prediction in urban open spaces.


Assuntos
Ruído , Som , China , Aglomeração , Humanos , Parques Recreativos
3.
Appl Ergon ; 98: 103603, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34638037

RESUMO

Auditory comfort evaluations are garnering increased attention in engineering and particularly in the context of air transportation. Being able to produce sound environments corresponding to various flight conditions in aircraft mock-ups would be a valuable tool to investigate acoustic comfort inside aircrafts in controlled environments. Before using such mock-ups, they must be developed and validated in physical and perceptual terms. This paper provides a perceptual validation of sound environment reproduction inside aircraft mock-up. To provide a faithfully reproduced sound environment, time, frequency and spatial characteristics should be preserved. Physical sound field reproduction approaches for spatial sound reproduction are required while properly preserving localization cues at the listener's ears to recreate a realistic and immersing sound environment. We report a perceptual validation of a sound field reproduction system developed in an aircraft mock-up based on multichannel least-square methods and equalization. Twenty participants evaluated reproduced sound environments relative to a reference sound environment in an aircraft cabin mock-up equipped with a 41-actuator multichannel sound reproduction system. Results indicate that the preferred reproduction corresponds to the best physical reconstruction of the sound environment.


Assuntos
Aeronaves , Som , Atenção , Sinais (Psicologia) , Humanos , Reprodução
4.
Ultrasonics ; 118: 106564, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34530395

RESUMO

Tissue-Mimicking Material (TMM) is defined on IEC International Standards and applied in assessing ultrasonic diagnostic and therapeutic equipment's basic safety and essential performance. One of the TMM that fits IEC standards specification has its recipe described at IEC 60601-2-37, and it is fabricated using glycerol (11.21 %), deionized water (82.95%), benzalkonium chloride (0.47 %), silicon carbide (0.53 %), aluminum oxide 0.3 µm (0.88%), aluminum oxide 3.0 µm (0.94 %), and agar (3.08 %). Glycerol is the component responsible for adjusting the TMM's speed of sound. Moreover, it is recommended to store TMM in a closed container immersed in a mixture of water (88.1 %)/glycerol (11.9 %) to prevent it from drying out and avoiding air contact. The literature points out TMM measurements underwater can alter the speed of sound property as TMM tends to lose glycerol. Herein, the authors proposed to assess the viability of measuring the TMM speed of sound in the water/glycerol maintenance solution. First, the authors characterized the maintenance solution's speed of sound for a temperature range of 20 °C to 45 °C. Then, the group velocity of a set of TMM was measured underwater and in the maintenance solution for the same temperature range. The respective group velocity expanded uncertainty was calculated. The results indicate it is feasible to measure TMM in the maintenance solution, achieving group velocity values with no statistical difference from the ones measured underwater in the temperature range of 20 °C to 40 °C.


Assuntos
Materiais Biomiméticos , Imagens de Fantasmas/normas , Som , Terapia por Ultrassom/instrumentação , Ultrassonografia/instrumentação , Óxido de Alumínio , Compostos de Benzalcônio , Calibragem , Compostos Inorgânicos de Carbono , Segurança de Equipamentos , Glicerol , Compostos de Silício , Temperatura , Água
5.
Sensors (Basel) ; 21(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34833554

RESUMO

Due to the strong absorption and attenuation of electromagnetic waves by water, radio communications and global positioning systems are lacking in the deep-sea environment. Therefore, underwater long-distance communications, positioning, detection and other functions depend on acoustic technology. In order to realize the above functions, the acoustic system of the Fendouzhe human occupied vehicle (HOV) is composed of eight kinds of sonars and sensors, which is one of the core systems of manned submersible. Based on the Jiaolong/Shenhai Yongshi HOVs, the acoustic system of the Fendouzhe HOV has been developed. Compared with the previous technology, there are many technical improvements and innovations: 10,000-m underwater acoustic communication, 10,000-m underwater acoustic positioning, multi-beam forward-looking imaging sonar, an integrated navigation system, etc. This study introduces the structure of the acoustic system of the Fendouzhe HOV and the technical improvements compared with the Jiaolong/Shenhai Yongshi HOVs. The results of the acoustic system are illustrated by the 10,000-m sea trails in the Mariana Trench from October to December 2020.


Assuntos
Acústica , Som , Humanos , Água
6.
Sensors (Basel) ; 21(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34833701

RESUMO

Imaging sonar systems are widely used for monitoring fish behavior in turbid or low ambient light waters. For analyzing fish behavior in sonar images, fish segmentation is often required. In this paper, Mask R-CNN is adopted for segmenting fish in sonar images. Sonar images acquired from different shallow waters can be quite different in the contrast between fish and the background. That difference can make Mask R-CNN trained on examples collected from one fish farm ineffective to fish segmentation for the other fish farms. In this paper, a preprocessing convolutional neural network (PreCNN) is proposed to provide "standardized" feature maps for Mask R-CNN and to ease applying Mask R-CNN trained for one fish farm to the others. PreCNN aims at decoupling learning of fish instances from learning of fish-cultured environments. PreCNN is a semantic segmentation network and integrated with conditional random fields. PreCNN can utilize successive sonar images and can be trained by semi-supervised learning to make use of unlabeled information. Experimental results have shown that Mask R-CNN on the output of PreCNN is more accurate than Mask R-CNN directly on sonar images. Applying Mask R-CNN plus PreCNN trained for one fish farm to new fish farms is also more effective.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Som , Manejo de Espécimes , Aprendizado de Máquina Supervisionado
7.
Medicine (Baltimore) ; 100(41): e27509, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34731137

RESUMO

BACKGROUND: Tinnitus is a common otological symptom and can be debilitating. Sound therapy has increased in popularity due to its potential for increased efficacy and fewer and milder side effects, but the available evidence is limited by the lack of randomized controlled trials comparing different sound therapies for tinnitus. Network meta-analysis (NMA) is a useful tool to compare multiple treatments when there is limited or no direct evidence available. The aim of this paper is to evaluate the efficacy and acceptability of different sound therapies for tinnitus. METHODS AND ANALYSIS: A literature search was conducted to identify articles in EMBASE, PubMed/MEDLINE, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Literature, and Wanfang and Weipu from inception to April 1, 2021. The Tinnitus Handicap Inventory, Tinnitus Questionnaire, and effective rate were used to assess perceived tinnitus suppression after treatment. We used Review Manager 5.4 for the standard meta-analysis; R 4.0.4 and Stata 15.1 were used for the NMA and the publication bias and sensitivity analyses. RESULTS: The effect estimates of the direct comparisons (when available) were very similar to those of the NMA. Overall, sound stimulation alone performed better than medication alone, educational consultation alone, and no treatment. Combination therapy, such as sound stimulation plus educational consultation and sound stimulation plus drug therapy, yielded significantly better outcomes with regard to the alleviation of tinnitus than individual treatments. CONCLUSION: This is the first NMA to evaluate and compare the effectiveness of different sound therapies for the management of tinnitus. It may help inform the selection of sound therapy and the development of guidelines in clinical practice. Future studies of sound therapy with larger sample sizes involving multiple medical centers are needed to improve the current evidence.


Assuntos
Estimulação Acústica/métodos , Avaliação Educacional/métodos , Som/efeitos adversos , Zumbido/terapia , Adulto , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metanálise em Rede , Aceitação pelo Paciente de Cuidados de Saúde , Padrões de Prática Médica , Sensibilidade e Especificidade , Resultado do Tratamento
8.
Sensors (Basel) ; 21(21)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34770635

RESUMO

Distinguishing between a dangerous audio event like a gun firing and other non-life-threatening events, such as a plastic bag bursting, can mean the difference between life and death and, therefore, the necessary and unnecessary deployment of public safety personnel. Sounds generated by plastic bag explosions are often confused with real gunshot sounds, by either humans or computer algorithms. As a case study, the research reported in this paper offers insight into sounds of plastic bag explosions and gunshots. An experimental study in this research reveals that a deep learning-based classification model trained with a popular urban sound dataset containing gunshot sounds cannot distinguish plastic bag pop sounds from gunshot sounds. This study further shows that the same deep learning model, if trained with a dataset containing plastic pop sounds, can effectively detect the non-life-threatening sounds. For this purpose, first, a collection of plastic bag-popping sounds was recorded in different environments with varying parameters, such as plastic bag size and distance from the recording microphones. The audio clips' duration ranged from 400 ms to 600 ms. This collection of data was then used, together with a gunshot sound dataset, to train a classification model based on a convolutional neural network (CNN) to differentiate life-threatening gunshot events from non-life-threatening plastic bag explosion events. A comparison between two feature extraction methods, the Mel-frequency cepstral coefficients (MFCC) and Mel-spectrograms, was also done. Experimental studies conducted in this research show that once the plastic bag pop sounds are injected into model training, the CNN classification model performs well in distinguishing actual gunshot sounds from plastic bag sounds.


Assuntos
Algoritmos , Redes Neurais de Computação , Coleta de Dados , Humanos , Som
9.
Sensors (Basel) ; 21(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34770658

RESUMO

The successful development of a system realizing color sonification would enable auditory representation of the visual environment. The primary beneficiary of such a system would be people that cannot directly access visual information-the visually impaired community. Despite the plethora of sensory substitution devices, developing systems that provide intuitive color sonification remains a challenge. This paper presents design considerations, development, and the usability audit of a sensory substitution device that converts spatial color information into soundscapes. The implemented wearable system uses a dedicated color space and continuously generates natural, spatialized sounds based on the information acquired from a camera. We developed two head-mounted prototype devices and two graphical user interface (GUI) versions. The first GUI is dedicated to researchers, and the second has been designed to be easily accessible for visually impaired persons. Finally, we ran fundamental usability tests to evaluate the new spatial color sonification algorithm and to compare the two prototypes. Furthermore, we propose recommendations for the development of the next iteration of the system.


Assuntos
Pessoas com Deficiência Visual , Dispositivos Eletrônicos Vestíveis , Algoritmos , Humanos , Som
10.
Sensors (Basel) ; 21(21)2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34770696

RESUMO

The computer modelling of condition monitoring sensors can aide in their development, improve their performance, and allow for the analysis of sensor impact on component operation. This article details the development of a COMSOL model for a guided wave-based temperature monitoring system, with a view to using the technology in the future for the temperature monitoring of nozzle guide vanes, found in the hot section of aeroengines. The model is based on an experimental test system that acts as a method of validation for the model. Piezoelectric wedge transducers were used to excite the S0 Lamb wave mode in an aluminium plate, which was temperature controlled using a hot plate. Time of flight measurements were carried out in MATLAB and used to calculate group velocity. The results were compared to theoretical wave velocities extracted from dispersion curves. The assembly and validation of such a model can aide in the future development of guided wave based sensor systems, and the methods provided can act as a guide for building similar COMSOL models. The results show that the model is in good agreement with the experimental equivalent, which is also in line with theoretical predictions.


Assuntos
Som , Transdutores , Animais , Simulação por Computador , Ovinos , Temperatura
11.
Sensors (Basel) ; 21(21)2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34770700

RESUMO

Damage detection in structural components, especially in mechanical engineering, is an important element of engineering practice. There are many methods of damage detection, in which changes in various parameters caused by the presence of damage are analysed. Recently, methods based on the analysis of changes in dynamic parameters of structures, that is, frequencies or mode shapes of natural vibrations, as well as changes in propagating elastic waves, have been developed at the highest rate. Diagnostic methods based on the elastic wave propagation phenomenon are becoming more and more popular, therefore it is worth focusing on the improvement of the efficiency of these methods. Hence, a question arises about whether it is possible to shorten the required measurement time without affecting the sensitivity of the diagnostic method used. This paper discusses the results of research carried out by the authors in this regard both numerically and experimentally. The numerical analysis has been carried out by the use of the Time-domain Spectral Finite Element Method (TD-SFEM), whereas the experimental part has been based on the measurement performed by 1-D Laser Doppler Scanning Vibrometery (LDSV).


Assuntos
Som , Vibração , Simulação por Computador , Lasers , Ultrassonografia Doppler
12.
Sensors (Basel) ; 21(21)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34770267

RESUMO

For high-resolution side scan sonar images, accurate and fast segmentation of sonar images is crucial for underwater target detection and recognition. However, due to the characteristics of low signal-to-noise ratio (SNR) and complex environmental noise of sonar, the existing methods with high accuracy and good robustness are mostly iterative methods with high complexity and poor real-time performance. For this purpose, a region growing based segmentation using the likelihood ratio testing method (RGLT) is proposed. This method obtains the seed points in the highlight and the shadow regions by likelihood ratio testing based on the statistical probability distribution and then grows them according to the similarity criterion. The growth avoids the processing of the seabed reverberation regions, which account for the largest proportion of sonar images, thus greatly reducing segmentation time and improving segmentation accuracy. In addition, a pre-processing filtering method called standard deviation filtering (STDF) is proposed to improve the SNR and remove the speckle noise. Experiments were conducted on three sonar databases, which showed that RGLT has significantly improved quantitative metrics such as accuracy, speed, and segmentation visual effects. The average accuracy and running times of the proposed segmentation method for 100 × 400 images are separately 95.90% and 0.44 s.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Funções Verossimilhança , Razão Sinal-Ruído , Som
13.
Sensors (Basel) ; 21(21)2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34770350

RESUMO

In the field of underwater vision, image matching between the main two sensors (sonar and optical camera) has always been a challenging problem. The independent imaging mechanism of the two determines the modalities of the image, and the local features of the images under various modalities are significantly different, which makes the general matching method based on the optical image invalid. In order to make full use of underwater acoustic and optical images, and promote the development of multisensor information fusion (MSIF) technology, this letter proposes to apply an image attribute transfer algorithm and advanced local feature descriptor to solve the problem of underwater acousto-optic image matching. We utilize real and simulated underwater images for testing; experimental results show that our proposed method could effectively preprocess these multimodal images to obtain an accurate matching result, thus providing a new solution for the underwater multisensor image matching task.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Acústica , Som , Visão Ocular
14.
Sensors (Basel) ; 21(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34770495

RESUMO

Based on the principle of underwater transducers, an ultrasonic four-laminated transducer with a frequency of 1 MHz was proposed to solve the problem of large energy attenuation when ultrasonic waves propagate in viscoelastic media. First, this study targeted solid rocket propellant as the research object, and the energy attenuation characteristics of ultrasonic waves propagating in viscoelastic media were analyzed through the derivation of the wave equation. Second, the structure of a four-laminated transducer with a frequency of 1 MHz was designed, and the resonance frequency was obtained by a graphical method. The sound field simulation and experimental results showed that the gain of the four-laminated transducer was 15 dB higher than that of the single-wafer transducer. An ultrasonic feature scanning system was built to complete the qualitative and quantitative detection of the smallest artificial hole (ϕ2 mm × 10 mm). Finally, two different natural defects were scanned, and the results were compared with those obtained using an industrial computed tomography detection system. The results showed that the ultrasonic method was more accurate in characterizing two natural defects. The primary cause was that the industrial CT was not sensitive to defects parallel to the incident direction of the ray. Therefore, this study not only achieved the qualitative and quantitative nondestructive testing of solid rocket propellants, but also provides an important reference for other viscoelastic components.


Assuntos
Transdutores , Ultrassom , Simulação por Computador , Som , Vibração
15.
Med Pr ; 72(5): 521-528, 2021 Nov 19.
Artigo em Polonês | MEDLINE | ID: mdl-34596171

RESUMO

BACKGROUND: The aim of the study was to assess the correct insertion of earplugs in the ear canal by people with different knowledge regarding this matter. The use of hearing protectors leads to a reduction in the risk of hearing loss, which is part of environmental engineering. MATERIAL AND METHODS: Measurements of sound attenuation by earplugs were carried out with the participation of 21 people with no experience in the use of earplugs. The measurements were repeated until the subjects had read the instructions for the use of earplugs, and then after the subjects had been trained in the correct insertion of earplugs in the ear canal. The tests were carried out using a newly developed portable device for quick measurements of sound attenuation. RESULTS: Familiarizing the subjects with the instructions for use resulted in a sound attenuation value being 6.7 and 3.3 dB higher, at 250 and 4000 Hz, respectively, compared to the measurement when the subjects inserted earplugs in the ear canal without any guidance. An even greater increase in attenuation was observed when the subjects were trained to insert earplugs, at 9.2 dB (250 Hz) and 5.4 dB (4000 Hz), respectively. In most cases, the changes in attenuation as a result of providing guidance were statistically significant. CONCLUSIONS: Persons who have no experience in using earplugs have significant problems with their correct insertion. Reading the instructions for use does not guarantee that earplugs will be inserted correctly. Only the training showing how to insert the earplugs correctly results in people being able to do it correctly in most cases. Med Pr. 2021;72(5):521-8.


Assuntos
Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Meato Acústico Externo , Dispositivos de Proteção das Orelhas , Humanos , Som
16.
PLoS One ; 16(10): e0258973, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34710145

RESUMO

In recent years, it is becoming clearer that plant growth and its yield are affected by sound with certain sounds, such as seedling of corn directing itself toward the sound source and its ability to distinguish stuttering of larvae from other sounds. However, methods investigating the effects of sound on plants either take a long time or are destructive. Here, we propose using laser biospeckle, a non-destructive and non-contact technique, to investigate the activities of an arugula plant for sounds of different frequencies, namely, 0 Hz or control, 100 Hz, 1 kHz, 10 kHz, including rock and classical music. Laser biospeckles are generated when scattered light from biological tissues interfere, and the intensities of such speckles change in time, and these changes reflect changes in the scattering structures within the biological tissue. A leaf was illuminated by light from a laser light of wavelength 635 nm, and the biospeckles were recorded as a movie by a CMOS camera for 20 sec at 15 frames per second (fps). The temporal correlation between the frames was characterized by a parameter called biospeckle activity (BA)under the exposure to different sound stimuli of classical and rock music and single-frequency sound stimuli for 1min. There was a clear difference in BA between the control and other frequencies with BA for 100 Hz being closer to control, while at higher frequencies, BA was much lower, indicating a dependence of the activity on the frequency. As BA is related to changes from both the surface as well as from the internal structures of the leaf, LSM (laser scanning microscope) observations conducted to confirm the change in the internal structure revealed more than 5% transient change in stomatal size following exposure to one minute to high frequency sound of 10kHz that reverted within ten minutes. Our results demonstrate the potential of laser biospeckle to speedily monitor in vivo response of plants to sound stimuli and thus could be a possible screening tool for selecting appropriate frequency sounds to enhance or delay the activity of plants. (337 words).


Assuntos
Brassica/fisiologia , Lasers , Folhas de Planta/fisiologia , Som , Estimulação Acústica
17.
Anal Chem ; 93(44): 14820-14827, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34714062

RESUMO

Photoacoustic imaging reveals great potential for the study of individual cells due to the rich imaging contrast for both label-free and labeled cells. However, previously reported photoacoustic imaging flow cytometry configuration suffers from inadequate imaging quality and challenge to distinguish multiple cells. In order to solve such issues, we propose a novel acoustic standing wave aided multiparametric photoacoustic imaging flow cytometry (MPAFC) system. The acoustic standing wave is introduced to improve the imaging quality and speed. Multispectral illumination along with cell geometry, photoacoustic amplitude, and acoustic frequency spectrum enables the proposed system to precisely identify multiple types of cells with one scanning. On the basis of the identification, elimination of melanoma cells, and targeted labeled glioma cells have been performed with an elimination efficiency of >95%. Additionally, the MPAFC system is able to image and capture melanoma cells at a lowest concentration of 100 cells mL-1 in pure blood. Current results suggest that the proposed MPAFC may provide a precise and efficient tool for cell detection, manipulation, and elimination in both fundamental and clinical studies.


Assuntos
Técnicas Fotoacústicas , Acústica , Diagnóstico por Imagem , Citometria de Fluxo , Som
18.
J Acoust Soc Am ; 150(4): 2695, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34717468

RESUMO

Ecological momentary assessment (EMA) outcome measures can relate people's subjective auditory experience to their objective acoustical reality. While highly realistic, EMA data often contain considerable variability, such that it can be difficult to interpret the results with respect to differences in people's hearing ability. To address this challenge, a method for "guided" EMA is proposed and evaluated. Accompanied and instructed by a guide, normal-hearing participants carried out specific passive and active listening tasks inside a real-world public lunch scenario and answered EMA questionnaires related to aspects of spatial hearing, listening ability, quality, and effort. In situ speech and background noise levels were tracked, allowing the guided EMA task to be repeated inside two acoustically matched, loudspeaker-based laboratory environments: a 64-channel virtual sound environment (VSE) and a three-channel audiology clinic setup. Results showed that guided EMA provided consistent passive listening assessments across participants and conditions. During active listening, the clinic setup was found to be less challenging than the real-world and the VSE conditions. The proposed guided EMA approach may provide more focused real-world assessments and can be applied in realistic laboratory settings to aid the development of ecologically valid hearing testing.


Assuntos
Auxiliares de Audição , Percepção da Fala , Avaliação Momentânea Ecológica , Audição , Humanos , Som
19.
J Acoust Soc Am ; 150(4): 3176, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34717465

RESUMO

The relationship between sound duration and detection threshold has long been thought to reflect temporal integration. Reports of species differences in this relationship are equivocal: some meta-analyses report no species differences, whereas others report substantial differences, particularly between humans and their close phylogenetic relatives, macaques. This renders translational work in macaques problematic. To reevaluate this difference, tone detection performance was measured in macaques using a go/no-go reaction time (RT) task at various tone durations and in the presence of broadband noise (BBN). Detection thresholds, RTs, and the dynamic range (DR) of the psychometric function decreased as the tone duration increased. The threshold by duration trends suggest macaques integrate at a similar rate to humans. The RT trends also resemble human data and are the first reported in animals. Whereas the BBN did not affect how the threshold or RT changed with the duration, it substantially reduced the DR at short durations. A probabilistic Poisson model replicated the effects of duration on threshold and DR and required integration from multiple simulated auditory nerve fibers to explain the performance at shorter durations. These data suggest that, contrary to previous studies, macaques are uniquely well-suited to model human temporal integration and form the baseline for future neurophysiological studies.


Assuntos
Benchmarking , Macaca , Animais , Limiar Auditivo , Humanos , Filogenia , Som
20.
J Acoust Soc Am ; 150(4): 2705, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34717471

RESUMO

The need to predict acoustic propagation through marine sediments that contain gas bubbles has become increasingly important for civil engineering and climate studies. There are relatively few in situ acoustic wave propagation studies of muddy intertidal sediments, in which bubbles of biogenic gas (generally methane, a potent greenhouse gas) are commonly found. We used a single experimental rig to conduct two in situ intertidal acoustical experiments to improve understanding of acoustic remote sensing of gassy sediments, eventually including gas bubble size distributions. In the first experiment, we measured sediment sound speed and attenuation between four aligned hydrophones for a quasi-plane wave propagating along the array. The second experiment involved a focused insonified sediment volume created by two transducers emitting coincident sound beams at different frequencies that generated bubble-mediated acoustic signals at combination frequencies. The results from sediment core analyses, and comparison of in situ acoustic velocity and attenuation values with those of water-saturated sediments, together provide ample evidence for the presence of in situ gas bubbles in the insonified volumes of sediments. These datasets are suitable for linear and non-linear inversion studies that estimate in situ greenhouse gas bubble populations, needed for future acoustical remote sensing applications.


Assuntos
Acústica , Som , Sedimentos Geológicos , Metano , Transdutores
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...