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1.
Sci Rep ; 12(1): 8553, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595792

RESUMO

Bowhead whales (Balaena mysticetus) face threats from diminishing sea ice and increasing anthropogenic activities in the Arctic. Passive acoustic monitoring is the most effective means for monitoring their distribution and population trends, based on the detection of their calls. Passive acoustic monitoring, however, is influenced by the sound propagation environment and ambient noise levels, which impact call detection probability. Modeling and simulations were used to estimate detection probability for bowhead whale frequency-modulated calls in the 80-180 Hz frequency band with and without sea ice cover and under various noise conditions. Sound transmission loss for bowhead calls is substantially greater during ice-covered conditions than during open-water conditions, making call detection ~ 3 times more likely in open-water. Estimates of daily acoustic detection probability were used to compensate acoustic detections for sound propagation and noise effects in two recording datasets in the northeast Chukchi Sea, on the outer shelf and continental slope, collected between 2012 and 2013. The compensated acoustic density suggests a decrease in whale presence with the retreat of sea ice at these recording sites. These results highlight the importance of accounting for effects of the environment on ambient noise and acoustic propagation when interpreting results of passive acoustic monitoring.


Assuntos
Baleia Franca , Acústica , Animais , Camada de Gelo , Som , Água
2.
Biomed Microdevices ; 24(2): 18, 2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35596837

RESUMO

Three-dimensional cell agglomerates are broadly useful in tissue engineering and drug testing. We report a well-free method to form large (1.4-mm) multicellular clusters using 100-MHz surface acoustic waves (SAW) without direct contact with the media or cells. A fluid couplant is used to transform the SAW into acoustic streaming in the cell-laden media held in a petri dish. The couplant transmits longitudinal sound waves, forming a Lamb wave in the petri dish that, in turn, produces longitudinal sound in the media. Due to recirculation, human embryonic kidney (HEK293) cells in the dish are carried to the center of the coupling location, forming a cluster in less than 10 min. A few minutes later, these clusters may then be translated and merged to form large agglomerations, and even repeatedly folded to produce a roughly spherical shape of over 1.4 mm in diameter for incubation-without damaging the existing intercellular bonds. Calcium ion signaling through these clusters and confocal images of multiprotein junctional complexes suggest a continuous tissue construct: intercellular communication. They may be formed at will, and the method is feasibly useful for formation of numerous agglomerates in a single petri dish.


Assuntos
Acústica , Som , Animais , Comunicação Celular , Meios de Cultura , Células HEK293 , Humanos , Ovinos
3.
Nat Commun ; 13(1): 2372, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501325

RESUMO

Spatiotemporal control of chemical cascade reactions within compartmentalized domains is one of the difficult challenges to achieve. To implement such control, scientists have been working on the development of various artificial compartmentalized systems such as liposomes, vesicles, polymersomes, etc. Although a considerable amount of progress has been made in this direction, one still needs to develop alternative strategies for controlling cascade reaction networks within spatiotemporally controlled domains in a solution, which remains a non-trivial issue. Herein, we present the utilization of audible sound induced liquid vibrations for the generation of transient domains in an aqueous medium, which can be used for the control of cascade chemical reactions in a spatiotemporal fashion. This approach gives us access to highly reproducible spatiotemporal chemical gradients and patterns, in situ growth and aggregation of gold nanoparticles at predetermined locations or domains formed in a solution. Our strategy also gives us access to nanoparticle patterned hydrogels and their applications for region specific cell growth.


Assuntos
Ouro , Nanopartículas Metálicas , Lipossomos , Som , Vibração
4.
Dtsch Arztebl Int ; 119(9): 144, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35535724

Assuntos
Som , Humanos
5.
Curr Biol ; 32(9): R408-R409, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35537387

RESUMO

Mimicry is one of the most fascinating phenomena in nature1. Mimicry traits often reflect complex, finely tuned, and sometimes extravagant relationships among species and have evolved to deceive predators or prey. Indeed, mimicry has most often evolved to discourage predation: the 'mimic' exhibits phenotypic convergence towards a non-related 'model' organism which is inedible or harmful, so that a given predator, or 'receiver', will refrain from attacking or ingesting the mimic. Traditionally, mimicry is mainly evident and has been mainly studied in the visual domain. Here, we report experiments that document the first case of interspecific acoustic mimicry in a mammal and demonstrate that the distress calls the greater mouse-eared bat (Myotis myotis) broadcasts when handled imitate sounds of stinging bees or wasps to discourage the bat's avian predators.


Assuntos
Quirópteros , Acústica , Animais , Insetos , Comportamento Predatório , Som
6.
Adv Exp Med Biol ; 1364: 411-422, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35508886

RESUMO

Skull bone is the main obstacle for transcranial ultrasound therapy and imaging applications. Most efforts in characterizing ultrasonic properties of the skull have been limited to a narrow frequency range and normal incidence. On the other hand, acoustic guided waves in plates have been used in non-destructive evaluation of materials and also to assess the strength of long bones. Recent work has likewise revealed the existence of skull-guided waves (SGWs) in mice and humans when performing measurements over a broad range of frequencies and incidence angles. Here we provide an overview on the recent progress in our understanding on the propagation of SGWs, describe the measurement techniques used to detect SGWs, the experimental observations, and the accompanying modeling efforts. Finally, the outstanding challenges to harness SGWs in applications such as transcranial therapy, imaging, and cranial bone assessment are discussed.


Assuntos
Crânio , Terapia por Ultrassom , Animais , Cabeça , Camundongos , Crânio/diagnóstico por imagem , Som
7.
Commun Biol ; 5(1): 410, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577891

RESUMO

The origins of human language remains a major question in evolutionary science. Unique to human language is the capacity to flexibly recombine a limited sound set into words and hierarchical sequences, generating endlessly new sentences. In contrast, sequence production of other animals appears limited, stunting meaning generation potential. However, studies have rarely quantified flexibility and structure of vocal sequence production across the whole repertoire. Here, we used such an approach to examine the structure of vocal sequences in chimpanzees, known to combine calls used singly into longer sequences. Focusing on the structure of vocal sequences, we analysed 4826 recordings of 46 wild adult chimpanzees from Taï National Park. Chimpanzees produced 390 unique vocal sequences. Most vocal units emitted singly were also emitted in two-unit sequences (bigrams), which in turn were embedded into three-unit sequences (trigrams). Bigrams showed positional and transitional regularities within trigrams with certain bigrams predictably occurring in either head or tail positions in trigrams, and predictably co-occurring with specific other units. From a purely structural perspective, the capacity to organize single units into structured sequences offers a versatile system potentially suitable for expansive meaning generation. Further research must show to what extent these structural sequences signal predictable meanings.


Assuntos
Pan troglodytes , Vocalização Animal , Animais , Evolução Biológica , Idioma , Som
8.
Sci Rep ; 12(1): 7655, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538135

RESUMO

As an Arctic gateway, the Norwegian Sea sustains a rich diversity of seasonal and resident species of soniferous animals, vulnerable to the effects of climate change and anthropogenic activities. We show the occurrence of seasonal patterns of acoustic signals in a small canyon off Northern Norway, and investigate cetacean vocal behavior, human-made noise, and climatic contributions to underwater sound between January and May 2018. Mostly median sound levels ranged between 68.3 and 96.31 dB re 1 µPa2 across 1/3 octave bands (13 Hz-16 kHz), with peaks in February and March. Frequencies under 2 kHz were dominated by sounds from baleen whales with highest rates of occurrence during winter and early spring. During late-spring non-biological sounds were predominant at higher frequencies that were linked mainly to ship traffic. Seismic pulses were also recorded during spring. We observed a significant effect of wind speed and ship sailing time on received sound levels across multiple distance ranges. Our results provide a new assessment of high-latitude continental soundscapes in the East Atlantic Ocean, useful for management strategies in areas where anthropogenic pressure is increasing. Based on the current status of the local soundscape, we propose considerations for acoustic monitoring to be included in future management plans.


Assuntos
Acústica , Som , Animais , Regiões Árticas , Cetáceos , Ruído , Navios
9.
JMIR Mhealth Uhealth ; 10(4): e33543, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35451975

RESUMO

BACKGROUND: Tinnitus is a phantom auditory sensation in the absence of an external stimulus. It is accompanied by a broad range of negative emotional symptoms and a significantly lower quality of life. So far, there is no cure for tinnitus, although various treatment options have been tried. One of them is mobile technology employing dedicated apps based on sound therapy. The apps can be managed by the patient and tailored according to their needs. OBJECTIVE: The study aims to assess the effect of a mobile app that generates background sounds on the severity of tinnitus. METHODS: The study involved 68 adults who had chronic tinnitus. Participants were divided into a study group (44 patients) and a control group (24 patients). For 6 months those in the study group used a free mobile app that enriched the sound environment with a background sound. Participants were instructed to use the app for at least 30 minutes a day using their preferred sound. The participants in the control group did not use the app. Subjective changes in the day-to-day functioning of both groups were evaluated using the Tinnitus Handicap Inventory (THI) questionnaire, a visual analog scale, and a user survey. RESULTS: After 3 months of using the app, the THI global score significantly decreased (P<.001) in the study group, decreasing again at 6 months (P<.001). The largest improvements were observed in the emotional and catastrophic reactions subscales. A clinically important change in the THI was reported by 39% of the study group (17/44). Almost 90% of the study participants (39/44) chose environmental sounds to listen to, the most popular being rain and ocean waves. In the control group, tinnitus severity did not change over 3 or 6 months. CONCLUSIONS: Although the participants still experienced limitations caused by tinnitus, the advantage of the app was that it led to lower negative emotions and thus reduced overall tinnitus severity. It is worth considering whether a mobile app might be incorporated into the management of tinnitus in a professional setting.


Assuntos
Aplicativos Móveis , Zumbido , Adulto , Humanos , Qualidade de Vida , Som , Inquéritos e Questionários , Zumbido/psicologia , Zumbido/terapia
10.
Sensors (Basel) ; 22(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35408325

RESUMO

In this paper, we propose a data-driven approach for the reconstruction of unknown room impulse responses (RIRs) based on the deep prior paradigm. We formulate RIR reconstruction as an inverse problem. More specifically, a convolutional neural network (CNN) is employed prior, in order to obtain a regularized solution to the RIR reconstruction problem for uniform linear arrays. This approach allows us to avoid assumptions on sound wave propagation, acoustic environment, or measuring setting made in state-of-the-art RIR reconstruction algorithms. Moreover, differently from classical deep learning solutions in the literature, the deep prior approach employs a per-element training. Therefore, the proposed method does not require training data sets, and it can be applied to RIRs independently from available data or environments. Results on simulated data demonstrate that the proposed technique is able to provide accurate results in a wide range of scenarios, including variable direction of arrival of the source, room T60, and SNR at the sensors. The devised technique is also applied to real measurements, resulting in accurate RIR reconstruction and robustness to noise compared to state-of-the-art solutions.


Assuntos
Redes Neurais de Computação , Som , Acústica , Algoritmos , Processamento de Imagem Assistida por Computador/métodos
11.
Sensors (Basel) ; 22(7)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35408351

RESUMO

This study extracts the energy characteristic distributions of the intrinsic mode functions (IMFs) and residue functions (RF) for a blue whale sound signal, with empirical mode decomposition (EMD) as the basic theoretical framework. A high-resolution marginal frequency characteristics extraction method, based on EMD with energy density intensity (EDI) parameters for blue B call vocalizations, was proposed. The extraction algorithm included six steps: EMD, energy analysis, marginal frequency (MF) analysis with EDI parameters, feature extraction (FE), classification, and Hilbert spectrum (HS) analysis. The blue whale sound sources were obtained from the website of the Scripps Whale Acoustics Lab of the University of California, San Diego, USA. The source is a type of B call with a time duration of 46.65 s, from which 59 analysis samples with a time duration of 180 ms were taken. The average energy distribution ratios of the IMF1, IMF2, IMF3, IMF4, and RF are 49.06%, 20.58%, 13.51%, 10.94% and 3.84%, respectively. New classification criteria and EDI parameters were proposed to extract the blue whale B call vocalization (BWBCV) characteristics. The analysis results show that the main frequency bands of the signal are distributed at 41-43 Hz in the MF of IMF1 for Class I BWBCV and 11-13 Hz in the MF of IMF2 for Class II BWBCV, respectively.


Assuntos
Balaenoptera , Acústica , Algoritmos , Animais , Processamento de Sinais Assistido por Computador , Som , Espectrografia do Som
12.
Artigo em Inglês | MEDLINE | ID: mdl-35457439

RESUMO

The unique architectural form and religious background of Taoist buildings can lead to a special acoustic environment, but there is a lack of research on the soundscape evaluation of Taoist buildings. Laojundong Taoist Temple was selected as the research site. The psychological and physiological responses of Taoist priests and ordinary people, and strategies for soundscape renovation were investigated by conducting field measurements, interviews, soundwalks, and audio-visual experiments. There was significant negative linear regression between the LAeq,5min and soundscape comfort (p < 0.01). The visual landscape comfort of ordinary people was notably correlated with landscape diversity (p < 0.01), whereas their soundscape comfort was markedly correlated with the degree of natural soundscape and audio-visual harmony (p < 0.01). The soundscape evaluation by Taoist priests was affected by their belief, activity types, social factors, and spatial positions. With the increasing proportion of the natural elements in the visual landscape in the temple, the acoustic comfort of Taoist priests and ordinary people significantly increased with the addition of bird sounds (p < 0.01). However, with the increasing proportion of Taoist scenes, Taoist music only significantly improved the acoustic comfort and heart rate of ordinary people (p < 0.01).


Assuntos
Música , Som , Acústica , China , Cabeça , Humanos
13.
Phys Med Biol ; 67(9)2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35366658

RESUMO

Major topics in medical ultrasound rest on the physics of wave propagation through tissue. These include fundamental treatments of backscatter, speed of sound, attenuation, and speckle formation. Each topic has developed its own rich history, lexicography, and particular treatments. However, there is ample evidence to suggest that power law relations are operating at a fundamental level in all the basic phenomena related to medical ultrasound. This review paper develops, from literature over the past 60 years, the accumulating theoretical basis and experimental evidence that point to power law behaviors underlying the most important tissue-wave interactions in ultrasound and in shear waves which are now employed in elastography. The common framework of power laws can be useful as a coherent overview of topics, and as a means for improved tissue characterization.


Assuntos
Técnicas de Imagem por Elasticidade , Som , Ultrassonografia
14.
Sci Rep ; 12(1): 6599, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459273

RESUMO

Recently, with the construction of smart city, the research on environmental sound classification (ESC) has attracted the attention of academia and industry. The development of convolutional neural network (CNN) makes the accuracy of ESC reach a higher level, but the accuracy improvement brought by CNN is often accompanied by the deepening of network layers, which leads to the rapid growth of parameters and floating-point operations (FLOPs). Therefore, it is difficult to transplant CNN model to embedded devices, and the classification speed is also difficult to accept. In order to reduce the hardware requirements of running CNN and improve the speed of ESC, this paper proposes a resource adaptive convolutional neural network (RACNN). RACNN uses a novel resource adaptive convolutional (RAC) module, which can generate the same number of feature maps as conventional convolution operations more cheaply, and extract the time and frequency features of audio efficiently. The RAC block based on the RAC module is designed to build the lightweight RACNN model, and the RAC module can also be used to upgrade the existing CNN model. Experiments based on public datasets show that RACNN achieves higher performance than the state-of-the-art methods with lower computational complexity.


Assuntos
Atenção , Redes Neurais de Computação , Som
15.
Sci Rep ; 12(1): 5905, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393525

RESUMO

Hearing is one of the earliest senses to develop and is quite mature by birth. Contemporary theories assume that regularities in sound are exploited by the brain to create internal models of the environment. Through statistical learning, internal models extrapolate from patterns to predictions about subsequent experience. In adults, altered brain responses to sound enable us to infer the existence and properties of these models. In this study, brain potentials were used to determine whether newborns exhibit context-dependent modulations of a brain response that can be used to infer the existence and properties of internal models. Results are indicative of significant context-dependence in the responsivity to sound in newborns. When common and rare sounds continue in stable probabilities over a very long period, neonates respond to all sounds equivalently (no differentiation). However, when the same common and rare sounds at the same probabilities alternate over time, the neonate responses show clear differentiations. The context-dependence is consistent with the possibility that the neonate brain produces more precise internal models that discriminate between contexts when there is an emergent structure to be discovered but appears to adopt broader models when discrimination delivers little or no additional information about the environment.


Assuntos
Percepção Auditiva , Aprendizagem , Estimulação Acústica/métodos , Adulto , Percepção Auditiva/fisiologia , Audição , Humanos , Recém-Nascido , Aprendizagem/fisiologia , Som
16.
Prog Brain Res ; 271(1): 71-99, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35397896

RESUMO

The hypothesis that fear is involved in the mechanisms of tonic immobility (TI) has been supported by early studies conducted in newborn and adult chickens. The susceptibility to TI changes during development in parallel to other fear responses. TI duration increases following exposure before induction to threatening stimuli such as electric shock, loud sound, stuffed sparrow hawk, as well as in unfamiliar conditions applied before and/or during testing. TI duration and susceptibility are increased by prey/predator eye contact and inversely related with the predator distance. TI duration increases following exposure before induction to threatening stimuli such as electric shock, loud sound, stuffed sparrow hawk, as well as in unfamiliar conditions applied before and/or during testing. The fact that the experimenter presence or the experimenter eye visibility represent a potential source of fear like a natural predator in chicks and in adult hens is controversial. The likely explanations for the contradictory results are discussed in the text. The rearing conditions, for instance, seem to be critical: repeated handling in the first days after hatching reduces the fear of human beings, decreasing TI duration in adulthood with a parallel increase in proximity scores to the experimenter. In chicks, exposure to withdrawal from a positive imprinting stimulus increases and decreases TI duration, respectively.


Assuntos
Galinhas , Medo , Adulto , Animais , Galinhas/fisiologia , Medo/fisiologia , Feminino , Humanos , Som
17.
Vet Rec ; 190(8): 329, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35420176

Assuntos
Ruído , Som , Animais
18.
Langmuir ; 38(15): 4763-4773, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35395155

RESUMO

Microwell arrays are ideal platforms for cell culturing, cell separation, and low-volume liquid handling. The ability to manipulate droplets in microwells could open up the opportunity for developing new biochemical assays. Here, we study the trapping of aqueous droplets in an oil-filled microwell driven by the application of nanometer amplitude vibrations called surface acoustic waves (SAW). We elucidate the dynamics of the droplet within the vortex toward the final trapping location and the physics of the trapping phenomenon using a theoretical model by considering the relevant forces. Our study revealed that the combined effect of acoustic radiation and hydrodynamic forces leads to droplet migration and trapping. We demarcate the trapping and nontrapping regimes in terms of the minimum critical input power required for the trapping of droplets of different sizes and densities. We find that the critical power varies as the square of the droplet size and is higher for a denser droplet. The effects of input power and droplet size on the trapping location and trapping time are also studied.


Assuntos
Hidrodinâmica , Som , Modelos Teóricos , Vibração , Água
19.
eNeuro ; 9(2)2022.
Artigo em Inglês | MEDLINE | ID: mdl-35410870

RESUMO

Temporal processing of complex sounds is a fundamental and complex task in hearing and a prerequisite for processing and understanding vocalization, speech, and prosody. Here, we studied response properties of neurons in the inferior colliculus (IC) in mice lacking Cacna2d3, a risk gene for autism spectrum disorders (ASDs). The α2δ3 auxiliary Ca2+ channel subunit encoded by Cacna2d3 is essential for proper function of glutamatergic synapses in the auditory brainstem. Recent evidence has shown that much of auditory feature extraction is performed in the auditory brainstem and IC, including processing of amplitude modulation (AM). We determined both spectral and temporal properties of single- and multi-unit responses in the IC of anesthetized mice. IC units of α2δ3-/- mice showed normal tuning properties yet increased spontaneous rates compared with α2δ3+/+ When stimulated with AM tones, α2δ3-/- units exhibited less precise temporal coding and reduced evoked rates to higher modulation frequencies (fm). Whereas first spike latencies (FSLs) were increased for only few modulation frequencies, population peak latencies were increased for fm ranging from 20 to 100 Hz in α2δ3-/- IC units. The loss of precision of temporal coding with increasing fm from 70 to 160 Hz was characterized using a normalized offset-corrected (Pearson-like) correlation coefficient, which appeared more appropriate than the metrics of vector strength. The processing deficits of AM sounds analyzed at the level of the IC indicate that α2δ3-/- mice exhibit a subcortical auditory processing disorder (APD). Similar deficits may be present in other mouse models for ASDs.


Assuntos
Transtorno do Espectro Autista , Colículos Inferiores , Estimulação Acústica , Animais , Percepção Auditiva/fisiologia , Transtorno do Espectro Autista/genética , Tronco Encefálico , Potenciais Evocados Auditivos do Tronco Encefálico/genética , Humanos , Colículos Inferiores/fisiologia , Camundongos , Som
20.
J Acoust Soc Am ; 151(4): 2624, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35461478

RESUMO

In this article, the application of spatial covariance matching is investigated for the task of producing spatially enhanced binaural signals using head-worn microphone arrays. A two-step processing paradigm is followed, whereby an initial estimate of the binaural signals is first produced using one of three suggested binaural rendering approaches. The proposed spatial covariance matching enhancement is then applied to these estimated binaural signals with the intention of producing refined binaural signals that more closely exhibit the correct spatial cues as dictated by the employed sound-field model and associated spatial parameters. It is demonstrated, through objective and subjective evaluations, that the proposed enhancements in the majority of cases produce binaural signals that more closely resemble the spatial characteristics of simulated reference signals when the enhancement is applied to and compared against the three suggested starting binaural rendering approaches. Furthermore, it is shown that the enhancement produces spatially similar output binaural signals when using these three different approaches, thus indicating that the enhancement is general in nature and could, therefore, be employed to enhance the outputs of other similar binaural rendering algorithms.


Assuntos
Localização de Som , Percepção da Fala , Som
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