bluuebunny/crossref_metadata_2025 huggingface dataset:
Launching underwater bioacoustics in Asia by Whitlow W. L. Au
Authors: Akamatsu Tomonari
Published: May 2022

Whitlow W. L. Au combined biosonar science with engineering. His studies influenced so many students in Asia no matter what their specialities, such as physiology, morphology, and physics. The epoch-making book “The Sonar of Dolphins” is an ideal example of his interdisciplinary approach. Whit educated young researchers in various ways even he did not notice. He led discussion among scientists that motivated current and new generations to conduct underwater and terrestrial bioacoustic research in the lab, in the forest and in the ocean. Quite a few attendees were from Asia at the series of biosonar symposiums in 1991 Moscow, in 1994 Harderwijk, and in 1998 Algarve, but the symposium held in 2009 Kyoto accommodated nearly 200 international specialists and half of them were Asian. An example of his influence was the towed and fixed passive acoustic monitoring in the Yangtze River, China, which revealed a range-wide distribution of finless porpoises collaborating with an international team. These techniques were applied later in India, Thailand, Malaysia, Nepal, Taiwan, Hongkong, and many other areas including Japan for the impact assessment of offshore wind farm developments. We owe him all the outcomes of underwater biosonar studies in Asia.
Optimization of cavitation-mediated mRNA delivery to cancer and non-cancer cells in vitro and in vivo
Authors: Martin Alexander , Smith Cameron , Carlisle Robert , Cleveland Robin O. , Coussios Constantin
Published: May 2022

The use of mRNA provides several compelling benefits. Cavitation-mediated delivery of mRNA has yet to be fully explored, especially in the context of achieving delivery of non-encapsulated, “free” mRNA. We present data that explore the relationship between cavitation and the transfer of, and protein expression from, free, fluorescently labelled mRNA. The protein expression exhibited in various cell lines in vitro was further tested in vivo, using sub-micron sized cavitation nuclei and the effects on transfection efficiency and expression time were examined. Acoustic exposure parameters were carefully selected, using a focused 0.5 MHz ultrasound transducer: pressure was varied from 0.3 to 2.1 MPa and 100–50 000 cycles at 5% duty cycle were used to achieve different cavitation regimes. A difference in expression time and transfection rate was observed between different cavitation nuclei and acoustic parameters. A luciferase reporter gene assay was used to characterise events in vitro. Expression due to cavitation-mediated delivery was further examined in vivo using the In Vivo imagining system and quantified using excised homogenised tumour tissue. These results provide us with a measurement window for maximum expression, exploration of how time points change across cell lines and lay the foundations for cavitation-mediated delivery and transfection of free mRNA.
Collaborative online assignments for an introductory course in musical acoustics
Authors: Piacsek Andrew A.
Published: May 2022

Hands-on activities are a valuable component of any introductory course in physical science, especially a course in musical acoustics that attracts students who are not majoring in a physical science. Tasks that require active engagement, both physical and cognitive, have been shown to improve retention of new concepts [Am. J. Phys. 80, 478 (2012)]. Such tasks also provide an opportunity for students to improve collaboration skills and to learn from each other. The development of a well-vetted library of interactive online physics simulations, such as PhET (https://phet.colorado.edu), and recent improvements in online collaboration platforms have enabled collaborative active learning to occur in a structured way outside the classroom. This presentation will describe three collaborative tasks for a general education course in musical acoustics at Central Washington University that were adapted for online and hybrid versions of thecourse. Each task makes use of freely available software. Examples of how the collaboration can be structured using Zoom and Gather.town will be provided.
Three-dimensional wavefront modeling of secondary sonic booms
Authors: Salamone Joseph A.
Published: May 2022

There is an abundance of previous work in the literature regarding the Mach cone of a supersonic vehicle and its associated ground intercepts identifying where and when the primary sonic boom reaches the ground. Likewise, there is excellent past research that models where the secondary sonic boom reaches the ground due to the reflection and refraction of the sonic boom emanating from above and below a supersonic vehicle. This work will provide a bridge between the two aforementioned aspects of past research. The Mach cone for both above the aircraft and below the aircraft after it reaches the ground will be extended to model the three-dimensional wavefront evolution of the secondary sonic boom as it propagates to the ground. The secondary sonic boom wavefronts modeled in this work will only consist of rays that refract in the vicinity of the stratosphere. The present work will show several cases of the secondary sonic boom wavefront propagation in three dimensions for a variety of aircraft headings and geographic locations around the world with representative upper air temperature and wind conditions.
Analysis of sonic booms from Falcon 9 booster landings
Authors: Durrant J T. , Gee Kent L. , Anderson Mark C. , Mathews Logan T. , Hart Grant W.
Published: May 2022

One drawback to the ability to land boosters of orbital launch vehicles, such as the Falcon 9, is the associated reentry sonic boom. Because of the Falcon 9 booster shape and landing orientation, the observed waveform at the ground contains three shocks (a triple boom), rather than the two associated with a traditional N-wave. To assess the impact of these sonic booms, acoustic data from a Falcon-9 booster landing at Vandenberg Space Force Base are analyzed. The data were collected in Lompoc, CA, at locations 7-14 km away from the landing site. Waveform and spectral characteristics are examined and various metrics, including A-weighted Sound Exposure Levels (ASEL), are calculated. These metrics from the reentry sonic booms are compared with metrics calculated from the launch noise.
Acoustic radiation force and torque on a spheroid near an interface
Authors: Simon Blake E. , Hamilton Mark F.
Published: May 2022

Acoustic radiation force and torque on a spheroid of arbitrary size near a rigid or pressure release interface are calculated using expansions of the pressure field in terms of both spherical and spheroidal wave functions. The spheroidal expansion coefficients are obtained by satisfying the boundary conditions at the interface and at the surface of the spheroid. Conditions at the interface are satisfied using a virtual (image) spheroid, while satisfying conditions at the spheroid surface require the use of addition theorems for spheroidal wave functions. The radiation force and torque are expressed as a summation of terms involving products of the coefficients in spherical wave expansions of the incident and scattered fields [Ilinskii et al., J. Acoust. Soc. Am. 144, 568–576 (2018)]. Far-field asymptotes are used to relate the spheroidal and spherical harmonic expansion coefficients analytically. Results from the present analytical model are compared with those from a finite-element model. The effect of the interface on the radiation force and torque relative to that on a spheroid in a free field is discussed. [B.E.S. is supported by the Applied Research Laboratories Chester M. McKinney Graduate Fellowship in Acoustics.]
An overview on the impact of nursing homes' acoustic characteristics on the elderly's quality of life
Authors: Naseer Saleh
Published: May 2022

The primary motivation for this study is that the acoustical features of elderly care facilities are frequently neglected. According to the centers for disease control and prevention, around 1.5 million senior individuals are in nursing homes in the USA in 2021. Some have a lower quality of life (QOL) due to health care concerns, social issues, and the home environmental issues. This paper intends to study the current investigations on the environmental issues and specifically acoustical issues around these types of facilities. Since hearing loss is a common chronic illness among the elderly, the acoustical issues will result in stronger impacts, e.g., making it difficult to communicate with staff and other elderly. In return, improving the quality of the indoor acoustic environment can help alleviate the physical weakness of hearing loss, which directly impacts their QOL. Similarly, some of the other chronic illnesses can be alleviated by improving nursing home’s acoustics quality, which can also result in an enhanced elderly's QOL. This study will provide a comprehensive overview by analyzing the methodology and results of the most relevant studies in this regard and making meaningful comparisons. This research aims to achieve an efficient research method for this type of study.
Ultrasound and microbubble-mediated blood-brain barrier disruption: Pre-clinical best practices
Authors: Ellens Nicholas
Published: May 2022

The combination of trans-cranial ultrasound and microbubbles has been shown to open the blood-brain barrier safely and reversibly. The potential for neurological therapies and functional imaging with this approach is enormous. The future success of this procedure requires robust pre-clinical research and carefully conducted clinical studies that lower the cost of the therapy without compromising patient safety. This talk focuses on the hardware necessary for successful pre-clinical studies in mice and rats. It will explore the pros and cons of off-the-shelf, turnkey systems; custom lab-developed systems; and repurposed clinical systems. It will discuss best practices for animal handling. Toward clinical translation, the talk will conclude with an overview of some of the regulatory hurdles faced by those trying to move these therapies into patients. With this, it will provide recommendations for things to consider in upstream experimental design.
Effect of microbubble and acoustic radiation force parameters on αvβ3–microbubble targeting
Authors: Castillo Jair I. , Navarro-Becerra J. A. , Borden Mark
Published: May 2022

Ultrasound molecular imaging (USMI) employs targeted microbubbles (MBs) decorated with specific ligands to enhance the local visualization of vascular structures. It has been demonstrated that cyclo Arg-Gly-Asp (cRGD) targeted MBs in combination with acoustic radiation force (ARF) can bind to αvβ3 integrins providing enhanced images of the tumor vasculature. Therefore, the goal of this work was to study and elucidate the role of ARF and MB parameters on the targeting of cRGD-MBs using an in vitro αvβ3-coated microvessel phantom. Labeled polydisperse and 2-μm size- isolated MBs decorated with cRGD with buried-ligand architecture (BLA) were pumped at 1 ml/h in an αvβ3-coated microvessel (D = 200 μm) and pushed using ARF. At higher monodisperse MB concentrations, the specific attachment follows a linear behavior independent of the frequency applied. However, at lower MB concentrations, the attachment becomes linearly dependent on the frequency. Finally, attachment of monodisperse population of RGD-MBs increased 8- and 3- fold than polydisperse MBs. In conclusion, we elucidated that the use of a monodisperse population of MBs improves the molecular specificity for αvβ3 integrins.
Improving upon standard approaches for mapping road traffic noise
Authors: Cook Mylan R. , Gee Kent L. , Transtrum Mark K. , Lympany Shane V. , Calton Matthew F.
Published: May 2022

The Federal Highway Administration’s Traffic Noise Model is the standard model used to predict traffic noise in the United States. The Department of Transportation’s National Transportation Noise Map (NTNM), based on average annual daily traffic counts, uses the traffic noise model to map out an average A-weighted equivalent sound level based on road traffic. Because the NTNM does not account for temporal variation, measured acoustic levels often differ from the average predicted levels. A recent internally developed method uses state highway agencies’ reported traffic counts to create a model to predict hourly traffic across the United States based on geospatial features. This predictive approach can be combined with acoustical propagation algorithms in the traffic noise model to create temporally variable traffic noise maps. Because predicted traffic counts match reported traffic counts more closely than averaged counts, predicted sound levels are more characteristic of measured sound levels than the NTNM. The expected sound level errors using the predictive approach are shown to be significantly smaller than the expected NTNM errors. [Work supported by U.S. Army SBIR.]
Mechanisms of masking by Schroeder-phase harmonic tone complexes in the budgerigar
Authors: Henry Kenneth , Wang Yingxuan , Abrams Kristina , Carney Laurel H.
Published: May 2022

Schroeder-phase harmonic tone complexes have a flattened temporal envelope and either rising or falling instantaneous frequency glides within F0periods, depending on the polarity of the phase relationship between harmonics. Human detection thresholds for a pure-tone target added to a Schroeder masker can be 10–15 dB lower for the negative Schroeder (upward gliding) compared to positive (downward gliding), possibly due to human cochlear mechanics though this hypothesis remains controversial. In contrast, several avian species show minimal behavioral masking differences between Schroeder polarities for F0s of 50 and 100 Hz. To gain further insight into the mechanisms of Schroeder masking, we performed operant-conditioning experiments in budgerigars, a parakeet species, including F0s up to 400 Hz that are potentially better matched to avian cochlear mechanics. Awake neurophysiological recordings at the midbrain processing level characterized neural encoding of behavioral test stimuli. Behavioral Schroeder masking thresholds decreased with increasing F0 and showed minimal difference between Schroeder polarities even at high F0s. Neural recordings showed prominent temporal and rate-based encoding of F0 periodicity and, in some neurons, marked response asymmetries between Schroeder polarities. These results suggest that neural response asymmetries between Schroeder polarities need not produce large behavioral masking differences for pure-tone targets.
Initial validations of an iterative hearing-aid self-fitting procedure with Monte-Carlo simulations
Authors: Kursun Bertan , Shola Chemay , Shen Yi
Published: May 2022

Self-directed gain adjustments may present a satisfactory solution for fitting a hearing aid (HA) without the requirement of supervision from a clinician. The current study develops a self-fitting procedure and provides initial evaluations of the procedure using Monte-Carlo simulations. In the procedure, the user interacts with the HA using a mobile device with a touch screen, while a continuous speech as a stimulus and a babble background noise is played in the room. The user explores the locations on the touch screen while hearing its effects on the hearing-aid processed audio in real time, until a preferred setting is identified. This adjustment process is repeated over trials, with the mathematical map between the touch-screen location (2D-coordinates) and the amplification profile of the HA being updated from trial to trial. This algorithm is evaluated using simulated listeners with known preferred amplification profiles serving as the ground truth. Results showed that estimates of the user preferred amplification profile, close to the ground truth, can be obtained by taking the mean of the user identified gain settings at the end of each trial.
Perception of prosodic cues to correct mistakes, in listeners with normal hearing and with cochlear implants
Authors: Wheeler Harley J. , Krogseng Tereza , Winn Matthew B.
Published: May 2022

Prosody is used to mark important information in speech yet is not an integral part of speech recognition testing among people with hearing difficulty. While a listener may correctly perceive words spoken, they may not perceive meaningful emphasis on a certain word, which could be critically important in a variety of everyday situations. This study introduces a new paradigm for assessing perception of prosodic cues in listeners with normal hearing and with cochlear implants, who have notorious difficulty perceiving pitch. Stimuli consisted of spoken sentences where one word (in various sentence positions) was emphasized in a manner that indicated that a prior statement was incorrect in a specific way. Participants used a visual analog scale to mark the timing and degree of emphasis aligned with the target words. Here, the perceptual data are linked with acoustic measures of voice pitch contour, intensity, duration, and vocal quality to characterize how contrastive stress cues are recovered by listeners with and without hearing impairment.
The effects of cochlear-implant processing and current spread on the weighting of spectrotemporal speech information in noise
Authors: Gibbs Bobby E. , Goupell Matthew J.
Published: May 2022

CI listeners show a different weighting of acoustic information in quiet compared to NH listeners. For example, they rely less on cues such as formant transitions. However, less is known about how CI listeners weight spectrotemporal speech information in noise. It is hypothesized that the spectrotemporal regions of noise that are most critical to intelligibility for CI listeners are distinct from those for NH listeners. Specifically, CI processing and current spread are hypothesized to shift importance towards coarse temporal regions. NH listeners should weight regions associated with formant transitions and rapid transients more heavily. To test these hypotheses, an experiment was designed to reveal spectrotemporal importance functions for speech-in-noise intelligibility in NH listeners presented unprocessed and CI-simulated stimuli. The stimuli will include unprocessed vowel-consonant-vowel words presented in “bubble” noise, which randomly attenuates different spectrotemporal regions. Listeners (N = 8 expected) will also be presented with vocoded stimuli with attenuation rates simulating broad or shallow current spread. Spectrotemporal importance functions will be assessed through point-biserial correlation by comparing how different bubble noise regions impact intelligibility. These data could help inform improvements in CI processing and noise-reduction strategies, which often assume relatively uniform weighting of acoustic information.
The changes to interaural acoustics imparted by placing circumaural headphones over bilateral cochlear-implant sound processors
Authors: Mayo Paul G. , Goupell Matthew J.
Published: May 2022

Interaural level differences (ILDs) are the primary binaural cue used by bilateral cochlear-implant (BiCI) listeners for horizontal-plane sound localization. As such, factors affecting their fidelity are important to understand. One approach for delivering binaural stimuli to BiCI listeners is to present virtually spatialized signals via circumaural headphones placed over the listener’s sound processors. An assumption of this approach is that the binaural cues presented are relatively unaltered by the transmission process and headphone placement; yet there is a lack of evidence supporting this assumption. Therefore, this study measured the effect of small changes to headphone placement on the ILDs received by BiCI sound processors. The intent was to determine both the extent and frequency range in which ILDs are affected using recordings of sine-sweeps received by the device microphones. Results show that slight changes in headphone placement affect coupling to the sound processor microphones and outer ear, primarily influencing ILDs between 1 and 5 kHz as much as 8.6 dB at the midline. They also show that occluding the listener’s ear canals with earplugs or moldable putty significantly reduces ILD variability from inconsistent headphone placement. In summary, these data suggest ways to improve this presentation method for BiCI research studies.
Controlling cylindrical waves using effective phononic crystals
Authors: Matlack Kathryn , Arretche Ignacio
Published: May 2022

Phononic crystals (PCs) are periodic media that can exhibit novel wave propagation behaviors. The analysis of PCs relies on the Bloch theorem, and the application of which implies that certain canonical behaviors can be supported, e.g., band gaps. The Bloch theorem assumes plane wave propagation; however, this is not always the case, e.g., for cylindrical or spherical wave fronts. Here, we redefine material properties in PCs in the presence of cylindrically propagating waves, such that the resulting wave equations contain periodic coefficients. In this sense, an equivalent system can be defined on which Bloch theorem can be applied to predict its wave response. This talk will discuss our recent work on effective phononic crystals, which are PCs that are not geometrically periodic but whose material properties result in periodic coefficients in the wave equation. We demonstrate these concepts using radially-propagating torsional waves and use finite element method models to solve for material properties that result in Bragg scattering-based band gaps, locally resonant band gaps, and topologically protected interface modes. Finally, we conduct experimental validations on 3D printed samples fabricated with multi-material polyjet printing. This work has applications to mitigating damaging torsional vibrations in rotating machinery such as turbines, compressors, and engines.
Mechanical models as ground truth for vowel resonance analysis
Authors: Shadle Christine H. , Chen Wei-Rong , Fulop Sean A. , Whalen D. H.
Published: May 2022

It has long been established that LPC analysis results in formant estimates that are not accurate representations of the resonances; they are biased towards the nearest harmonic, and this bias worsens as F0 rises to 200 Hz or more. Manual measurement of formants with the reassigned spectrogram (RS) has been shown to be more accurate, but the ground truth is needed in order to test automatic measurement methods. Here, “vocal tract” models were 3D-printed to allow resonances to be excited replicably. Using the principle of acoustic reciprocity, source signals were played over an external loudspeaker, and the output filtered by the model was recorded via a microphone located in the model’s “glottis.” A white noise source signal was used to determine the resonances. Sawtooth and impulse train source signals (F0s 83–400 Hz) were filtered by the physical model and then analyzed with both LPC and RS. LPC formants were biased towards the nearest harmonic, resulting in errors from 10 Hz at low F0 to 250 at 300 Hz. RS errors ranged from 0 to 20 Hz and were not correlated with F0. These results indicate physical models are useful for creating known resonances for validating accuracy in our measurements.
Evaluating the accuracy of forced alignment across Mandarin varieties
Authors: Liu Suyuan , Sóskuthy Márton
Published: May 2022

Forced alignment is widely used in phonetics to align transcripts with acoustic signals. These tools are trained on specific language varieties; it is unclear if they generalize to others. Previous research on English by MacKenzie and Turton (2020) finds good agreement between automated and human alignments for varieties that differ from the training variety. Such evaluation has only been carried out for English. We evaluate the level of human-aligner agreement on four Mandarin varieties (Canto, Shanghai, Beijing, and Tianjin). For each variety, two recordings from the HUB5 Corpus (LDC 1998) were aligned manually and by the Montreal Forced Aligner [McAuliffe et al. (2017)] using acoustic models trained on Beijing, Wuhan, and Hekou Mandarin [Schultz (2002)]. We find strong agreement between human and machine-aligned phone boundaries, with 17 ms as the median onset displacement. A mixed model identifies little variation across varieties or according to speech rate, but significant interindividual variation. Notably, despite the generally close agreement between the machine and human alignments, for two of the speakers, more than 10% of the alignments are displaced by over 100 ms. In sum, the Mandarin forced-aligner yields reliable alignments for out-of-training varieties, but manual checking of the results is still crucial.
An experimental model for the study of tracheoesophageal phonation
Authors: Miazaki da Costa Tourinho André , da Silva Andrey R.
Published: May 2022

Tracheoesophageal speech is the most widely used method of speech rehabilitation for those who have undergone a total laryngectomy. Despite its high success rate, the interplay between different factors may inhibit voice production. Among these factors, the amount of muscle contraction in the pharyngoesophageal segment is the most significant one. The present work is aimed at studying the effect of muscle contraction on tracheoesophageal voice production. An experimental model has been developed, in which a silicone tube, acting as the pharyngoesophageal segment, is connected at both ends to rigid tubes representing the pharynx and the esophagus. The effect of the musculature of the pharyngoesophageal segment has been included in the model by two different components. The first one, modeling the tendency of the muscle layer to close the pharyngoesophageal segment, has been taken into account by placing the tube inside a pressurized chamber. The second, modeling the stretching caused by longitudinal muscle fibers, has been included by means of a sliding device in one of the terminations of the silicone tube. The necessary parameters for self-sustained oscillations to occur were measured and compared with predictions made by a mathematical model [Tourinho et al., J. Acoust. Soc. Am. 149, 1979–1988 (2021)].
A practical spatially oversampled array concept enabling reconfigurability
Authors: Trickey Stephen , Daley Kirk , Bautista Alvaro , Kirkendall Clay
Published: May 2022

Typically, acoustic arrays are cut for a desired performance characteristic where acoustic performance is balanced with physical and cost constraints. Once constructed, the sensor placement in the array is fixed in a permanent configuration. Adaptive processing techniques can be used to optimize the acoustic characteristics of the array but are bounded by the fixed sensor placement. Reconfigurable arrays, where the sensor locations and apertures can be dynamically adjusted, can offer improved acoustic performance and signal processing power savings for a given array aperture. This work presents a new concept for fiber optic hydrophone arrays that uses a highly spatially oversampled multiplexing strategy enabling a large degree of flexibility in sensing configuration. The ease of multiplexing optical hydrophones allows for implementing the oversampled strategy with no additional processing hardware required. A review of fiber optic acoustic sensing and the optical techniques required to implement high performance spatially oversampled arrays will be presented. [DISTRIBUTION STATEMENT A. Approved for public release. Distribution is unlimited.]
Denoising and deconvolving sperm whale data in the northern Gulf of Mexico
Authors: Leftwich Kendal , Ioup Juliette W.
Published: May 2022

The Fourier wavelet based regularized deconvolution (ForWaRD) algorithm is a combination of Fourier deconvolution and wavelet denoising originally proposed by Neelamani et al. (2004) and modified by Herrera et al. (2006). The research described here uses the ForWaRD algorithm with recent broadband underwater acoustic data from sperm whales acquired in the northern Gulf of Mexico. Several modifications were required for the algorithm to yield the best results. Applying wavelet denoising and Fourier deconvolution allows smoothing of the data and separating a signal from the impulse response. Results indicate that the modification of using lease squares deconvolution instead of Weiner deconvolution improves the percent error in data reconstruction with our underwater acoustic data. Other modifications made to the type of wavelet thresholding as well as the wavelet choice for wavelet decomposition greatly improve the error in reconstruction of the signal. Results will be shown as well as an outline of the modifications.
Pacific Echo: A deep ocean collaborative experiment
Authors: Chapman Ross
Published: May 2022

This paper summarizes experiments carried out using towed line arrays in the Pacific Echo sea trials. Although John Preston was not a participant, the experiments are examples consistent with his efforts in promoting collaborative research at sea with horizontal arrays. The overall goal of Pacific Echo was to study the impact of thin sediment ocean bottom environments on sound propagation in deep water. The objective of the experiments described here was to study the evolution of young oceanic crust. The hypothesis was that the sound speed of young basalt increased with age of the crust. Sound speed was inferred from low frequency measurements of the reflection coefficient versus grazing angle at sites of increasing distance from the deep ocean spreading center. The experiments introduced a novel design for measuring the reflection coefficients using two ships and small explosive charges. The signals at the array were spatially filtered to resolve the specular reflections as the ships opened range on set courses. The data provided estimates of both the compressional and shear wave speeds of the basalt. Results from the broadside reflection technique showed that sound speed increased with crustal age and were consistent with measurements obtained from conventional seismic reflection surveys.
Non-cuboid Iterative room optimizer
Authors: D'Antonio Peter , Petrolli Rinaldi P.
Published: May 2022

In past years, various iterative optimization programs emerged to separately determine the optimal room ratios, sources and listening positions of perfectly reflective cuboid rooms, using the image-source model. Despite its fast computation times, this approach does not account for scattering, phase change at the boundary and cannot be extended to non-cuboid rooms. This presentation describes the current status of a program called NIRO, that offers a solution to those issues, by using the Boundary Element Method (BEM) to compute the frequency response from 20–200 Hz, considering the effects of the boundary’s complex admittance and all acoustical elements inside the room. With BEM as its engine, a room optimization genetic algorithm was developed to optimize source and receiver positions simultaneously with the room geometry, aiming to present the best possible acoustic environment given imposed restraints. To control the room's temporal decay, low-frequency acoustic treatments were added to the BEM model. By using transfer matrix models, the acoustical behavior of different multilayered treatments can be modeled and inserted into the BEM simulation to evaluate the change in the room’s acoustic field and in the frequency response at the receiving positions. 3D waterfall plots illustrate the temporal decay following optimization. Examples will be presented.
Modeling of micro-slit /perforated panels in multilayers for efficient design and validation of broadband sound absorbers
Authors: Xiang Ning , Hoeft Michael , Fackler Cameron J.
Published: May 2022

This work focuses on design of multilayer micro-perforated/slit panels (MPP/MSP) to create high sound absorption over a wide bandwidth. Theoretically micro-slit panels are equivalent to micro-perforated panels and can similarly achieve high absorption coefficients. Yet, fabrication of microslit panels is much easier. Using transparent panels, they are visually more transparent than MPPs since the MSPs yield more unobstructed panel for a given perforation rate. However, MPP and MSP absorbers in single setting are frequency limited to a bandwidth often not sufficient in applications. Stacking multilayered MPP/MSP panels, a high absorption becomes achievable in a wider bandwidth. Using existing single-panel MPP/MSP models, a transfer matrix method is suitable for cascading multilayers to predict overall absorption performance. This prediction model is applied to a Bayesian framework in coping with design challenges arising from designing MPP/MSP parameters for multiple layers that fulfills a given design scheme. The Bayesian design reported here rapidly converges to a parsimonious number of layers with optimized parameters for each layer, and the overall absorption is able to fulfill the design scheme for minimally possible fabrication complexity. In addition, performing iterative Bayesian analysis during the panel fabrication and experimental validation guides corrections due to fabrication inaccuracies.
Horseshoe bats use not changes in echo delay but Doppler shift to perceive approaching objects
Authors: Yoshida Soshi , Hase Kazuma , Heim Olga , Kobayasi Kohta I. , Hiryu Shizuko
Published: May 2022

Echolocating bats use echo delay for target ranging and Doppler shift information for relative velocity recognition. However, how they perceive moving objects remains unclear. To investigate this question, we played back echolocation pulses in real-time as virtual echoes to Japanese horseshoe bats (Rhinolophus ferrumequinum nippon) on a perch in a flight room. Since echoes coming back from an approaching object are theoretically characterized by both changes in echo delay and the presence of Doppler shift, we reproduced an artificial approaching object by encoding these two acoustic parameters in the virtual echoes. As a result, only Doppler shift evoked bats flight reaction, showing that they use only Doppler shift and not change in echo delay to perceive approaching objects. Also, we played back only constant frequency (CF) component and confirmed that they use the CF component to detect Doppler shift. Furthermore, as a response to the Doppler shift in the perceived echo, bats increased the bandwidth of the terminal component of their pulse. Surprisingly, this response occurred in the very first pulse after Doppler shift, which indicates bats can adapt their echolocation pulse characteristics to changing situations within a pulse. [This work was supported by JSPS KAKENHI Grant Nos. 18H03786 and 16H06542.]
Modeling the potential for vessel collision with southern resident killer whales
Authors: Cusano Dana A. , Reeve Molly , Weirathmueller Michelle , Zammit Karlee , Connell Steven , Zeddies David
Published: May 2022

Agent-based models can be used to simulate the behavior of animals within a stimulus field. For example, such models are used to estimate the sound exposure of simulated animals ("animats") moving within a computed sound field. This approach has not yet been used to estimate the probability of vessel collision between marine mammals and ships. One reason is the difficulty of defining aversive behavior in response to disturbance. While many animals display aversion, models often use a simplified approach due to insufficient data. Building on the JASCO animal simulation model including noise exposure (JASMINE), a vessel collision framework was developed for southern resident killer whales (SRKWs) using modeled vessel sound fields and AIS data. Animats were programmed to increasingly avoid louder, closer, and additional vessels by changing their heading, speed, and behavioral state based on published data from SRKWs. Animats that remained within a calculated "encounter radius" despite aversive behavior were considered struck by the vessel. Parameters governing aversive behaviors were calibrated by comparing the proportion of animats struck in the simulation with the collision probability for real-world SRKWs. This model provides a starting point to model the risk of vessel collision for SRKW and other species.
Natural cues for invertebrate and fish hearing: Particle motion measurements on coral reefs
Authors: Jones Ian T. , Gray Michael , Mooney T. Aran
Published: May 2022

Coral reef soundscapes are increasingly studied for their ecological uses by invertebrates and fishes, their applications for monitoring habitat quality, and to investigate effects of anthropogenic noise pollution. Few examinations of aquatic soundscapes have reported particle motion levels and variability, despite their relevance to invertebrates and fishes. We quantified ambient particle acceleration from orthogonal hydrophone arrays over several months at four coral reef sites in the U.S. Virgin Islands, which varied in benthic habitat and fish communities. Temporal trends of particle acceleration were similar to those of sound pressure, and the strength of diel trends in both metrics significantly correlated with percent coral cover. Low frequency (<100 Hz) and high magnitude empirical particle acceleration levels diverged from plane wave approximations. Particle acceleration levels were also determined for boat and example fish sounds. Comparisons with particle acceleration derived audiograms suggest greatest capacity of invertebrates and fishes to detect soundscape components below 100 Hz, and potentially poorer detectability of soundscape cues by some invertebrates compared to fishes. Based on our results, we discuss research questions in soundscape ecology for which reporting of particle motion is essential versus those for which sound pressure may suffice.
Long-term monitoring of a seagrass meadow using wideband acoustic measurements
Authors: Ballard Megan , Lee Kevin M. , Capistrant-Fossa Kyle , Wilson Preston S. , McNeese Andrew R. , Dunton Kenneth H.
Published: May 2022

Seagrasses are sentinel species whose sensitivity to changing water conditions makes them an indicator for sea level rise and climate change. The biological processes and physical characteristics associated with seagrass are known to affect acoustic propagation due to gas bodies contained within the seagrass tissue as well as photosynthesis-driven bubble production that results in free gas bubbles in the water. In this work, acoustical methods are applied to monitor seagrass biomass and gas ebullition with an autonomous field-deployed system using broadband acoustic measurements. Supporting environmental measurements including water temperature and salinity, dissolved oxygen, and photosynthetically active radiation (PAR) were also collected and used to interpret the acoustic data. A ray-based propagation model that includes losses due to the dispersion, absorption, and scattering of sound is applied to relate the measured acoustic signals to the gas bodies in the seagrass tissue and free bubbles in the water. This talk will present preliminary results from the first six months of a year-long deployment of the acoustic system in a dense seagrass meadow dominated by Thalassia testudinum (turtle grass) in Corpus Christi Bay, Texas (Gulf of Mexico). [Work supported by NSF.]
Coral reef & temperate coastal soundscape features evident in directional and omnidirectional passive acoustic time series
Authors: Freeman Lauren A. , Freeman Simon , Thode Aaron M. , Caspers Philip
Published: May 2022

Biologically complex coastal environments, such as coral reefs, demonstrate an equally rich ambient soundscape. Bioacoustic features of coastal soundscapes are closely tied with relative ecosystem health, functional groups present, and can be linked with specific behaviors. Biological contributions to ambient soundscapes have distinctive qualities as compared to sound associated with physical processes (i.e. wind and wave noise). While some biological components are readily identifiable, such as marine mammal or fish calls, the background noise associated with hundreds of thousands of biological clicks, snaps, and pops is not as well studied but contains a wealth of information about the ecosystem. A 64-element line array with 4.5 kHz design frequency was deployed for several field experiments off the coast of Kona, Hawaii in 2019 and 2020. Soundscape data from Hawaii were compared with comparable omnidirectional time series from Bermuda (2020) and coastal New England rocky reefs (2020–2021). Similarities in certain spectral features associated with biological sound sources were found between these unique ecosystems. The characteristic coral reef evening chorus, or significant increase in sound levels immediately prior to sunset, was consistent in Hawaii and Bermuda with comparable crepuscular changes in coastal New England.
Improved characterization of ambient sound levels in a coastal environment via use of an unmanned wave glider
Authors: Iafrate Joseph , Dossot Georges , Watwood Stephanie
Published: May 2022

In this project, we use an unmanned Liquid Robotics SV3 wave glider as a tool for basic research studying ambient acoustics in shallower, coastal waters off the coast of East-Central Florida. The primary objective is to characterize sound levels in varying conditions via collection of high-resolution environmental data. The SV3 is used to systematically characterize the acoustic environment in coastal waters, while simultaneously measuring oceanographic parameters such as wind speed, wind direction, and wave height. Quantifying the influence of these fundamental oceanographic influences on shallow water acoustics will provide improved characterization of surface noise and comparison with traditional ambient noise spectra. Ambient noise spectra will be presented for various sea states and wind scenarios, as measured at 25 foot depth using a towfish attached to the SV3. Some of these measurements are also compared to fixed station bottom recordings. Finally, this effort also includes characterization of unique sources of biological sounds recorded by the SV3, including not previously documented loud fish chorusing in this region.
The geometry of domain-general performance monitoring in the human medial frontal cortex
Authors: Fu Zhongzheng , Beam Danielle , Chung Jeffrey M. , Reed Chrystal M. , Mamelak Adam N. , Adolphs Ralph , Rutishauser Ueli
Published: May 2022

Controlling behavior to flexibly achieve desired goals depends on the ability to monitor one’s own performance. It is unknown how performance monitoring can be both flexible, to support different tasks, and specialized, to perform each task well. We recorded single neurons in the human medial frontal cortex while subjects performed two tasks that involve three types of cognitive conflict. Neurons encoding conflict probability, conflict, and error in one or both tasks were intermixed, forming a representational geometry that simultaneously allowed task specialization and generalization. Neurons encoding conflict retrospectively served to update internal estimates of conflict probability. Population representations of conflict were compositional. These findings reveal how representations of evaluative signals can be both abstract and task-specific and suggest a neuronal mechanism for estimating control demand.
Response to Comment on “Discovery of davemaoite, CaSiO
3
-perovskite, as a mineral from the lower mantle”
Authors: Tschauner Oliver , Huang Shichun , Humayun Munir , Liu Wenjun , Rossman George R.
Published: May 2022

Walter
et al
. issue a number of critical comments on our report about the discovery of davemaoite to the end that they believe to show that our results do not provide compelling evidence for the presence of davemaoite in the type specimen and that the hosting diamond had formed in the lithosphere. Their claim is based on a misinterpretation of the diffraction data contained in the paper, an insufficient analysis of the compositional data that disregards the three-dimensional distribution of inclusions, and the arbitrary assumption that Earth’s mantle shows no lateral variations in temperature, inconsistent with state-of-the-art assessments of mantle temperature variations and with their own published results.
Distribution of
Achromobacter
Species in 12 French Cystic Fibrosis Centers in 2020 by a Retrospective MALDI-TOF MS Spectrum Analysis
Authors: Garrigos Thomas , Dollat Manon , Magallon Arnaud , Folletet Anaïs , Bador Julien , Abid Maryam , Amara Marlène , Beauruelle Clémence , Belmonte Olivier , Boyer Pierre , Cardot-Martin Emilie , Cauchie Anne-Gaëlle , Colin de Verdière Sylvie , Daurel Claire , Gaudru Cécile , Hamdad Farida , Héry-Arnaud Geneviève , Hoellinger Baptiste , Lamoureux Claudie , Lartigue Marie-Frédérique , Malandain Damasie , Marchand Océane , Piau Caroline , Picot Sandrine , Revillet Hélène , Sabouni Zeina , Neuwirth Catherine , Amoureux Lucie
Published: May 2022

Achromobacter
spp. are nonfermenting Gram-negative bacilli mainly studied among cystic fibrosis (CF) patients. The identification of the 19 species within the genus is time-consuming (
nrdA
-sequencing), thus data concerning the distribution of the species are limited to specific studies.
Salmonella Facilitates Iron Acquisition through UMPylation of Ferric Uptake Regulator
Authors: Jia Haihong , Song Nannan , Ma Yue , Zhang Fengyu , Yue Yingying , Wang Weiwei , Li Cuiling , Li Hui , Wang Qi , Gu Lichuan , Li Bingqing
Published: May 2022

Salmonella
is the major pathogen causing bacterial enteric illness in both humans and animals. Iron availability is strictly controlled upon
Salmonella
entry into host cells.
The Pathogenic Yeast Candida parapsilosis Forms Pseudohyphae through Different Signaling Pathways Depending on the Available Carbon Source
Authors: Rupert Christopher B. , Rusche Laura N.
Published: May 2022

Candida parapsilosis
is one of the leading causes of hospital-acquired yeast infections and poses a significant risk to immunocompromised people. Two of its properties that contribute to infection are metabolic flexibility, to use a range of nutrients available in the host, and cellular dimorphism, to switch between round yeast cells and chains of elongated pseudohyphal cells.
Approximation of a Microbiome Composition Shift by a Change in a Single Balance Between Two Groups of Taxa
Authors: Odintsova Vera E. , Klimenko Natalia S. , Tyakht Alexander V.
Published: May 2022

The method proposed here extends the range of compositional methods providing interpretation of classical statistical tools applied to data converted to the ILR coordinates. It provides a strictly optimal solution in several special cases. The approach is universally applicable to compositional data of any nature, including microbiome data sets.
Multidrug Resistance Genes Carried by a Novel Transposon Tn
7376
and a Genomic Island Named MMGI-4 in a Pathogenic Morganella morganii Isolate
Authors: Luo Xing-Wei , Liu Pei-Yi , Miao Qing-Qing , Han Rong-Jia , Wu Hua , Liu Jian-Hua , He Dan-Dan , Hu Gong-Zheng
Published: May 2022

Mobile genetic elements (MGEs), especially for IS
26
-bounded translocatable units, may act as a reservoir for a variety of antimicrobial resistance genes in clinically important pathogenic bacteria. We expounded this significant genetic characteristic by investigating a representative
M. morganii
isolate containing multidrug resistance genes, including the infrequent
dfrA24
.
A Leak-Free Inducible CRISPRi/a System for Gene Functional Studies in Plasmodium falciparum
Authors: Liang Xiaoying , Boonhok Rachasak , Siddiqui Faiza Amber , Xiao Bo , Li Xiaolian , Qin Junling , Min Hui , Jiang Lubin , Cui Liwang , Miao Jun
Published: May 2022

Understanding the fundamental biology of malaria parasites through functional genetic/genomic studies is critical for identifying novel targets for antimalarial development. Conditional knockout/knockdown systems are required to study essential genes in the haploid blood stages of the parasite.