bluuebunny/crossref_metadata_2025 huggingface dataset:
Detecting myocardial perfusion deficit with contrast-enhanced high frame rate ultrasound
Authors: Wahyulaksana Geraldi , Wei Luxi , Te Lin Hekkert Maaike , Bowen Daniel J. , Raposo Loff Barreto Bernardo , van der Steen Antonius F. , Vos Hendrik
Published: April 2023

Imaging the myocardial perfusion after a heart attack has a high prognostic value, because it can guide the clinicians for better treatment before, during, or after percutaneous coronary intervention (PCI). Contrast-enhanced ultrasound is a promising imaging modality because it can be performed quickly on bedside within or outside the Cathlab. However, the image quality may generally not be good enough for accurate assessment of the myocardial perfusion. We have developed a technique that uses higher-order singular value decomposition of high frame rate echocardiographic data, in combination with contrast-specific pulsing schemes, to detect flow and perfusion. To assess the sensitivity of our technique to detect the local interruption of myocardial perfusion, we performed in vivo measurements on a porcine model. The left anterior descending coronary artery was occluded by using a balloon catheter which mainly interrupted the flow into the apex of the heart. Data were acquired with an ultrasound research scanner and phased array, and processed offline. The results showed that we can localize the blood flow inside the myocardium and detect the interrupt when the vessel is occluded, which shows the first proof of concept.
Using machine learning to reconstruct room geometry from an impulse response
Authors: Algargoosh Alaa , Singh Nikhil
Published: April 2023

Machine learning in room acoustics is an emerging field with great potential yet to be explored. Previous research includes predicting acoustic properties such as the impulse response from visual features that include an image of a room. However, one application that can significantly transform the architectural acoustics design process is reconstructing the room geometry based on its acoustic properties. This paper explores applying machine learning in predicting room geometry from an impulse response. The research aims to provide a tool for architects to design a room based on the desired acoustic experience.
Transient elastography with focused shear wave beams
Authors: Cormack John M. , Chao Yu-Hsuan , Archer Branch T. , Kim Kang , Spratt Kyle S. , Hamilton Mark F.
Published: April 2023

Transient elastography (TE) is a clinically available ultrasound elastography technique in which mechanical vibration of a small piston at the tissue surface generates a short shear wave pulse that propagates into the body. The piston doubles as an ultrasonic transducer; thus, the shear wave propagation is measured with pulse-echo ultrasound along the beam axis, yielding the wave speed and tissue stiffness. The long shear wavelength compared to piston diameter used in current devices results in low shear wave signal that decays rapidly on axis as the shear wave spreads in all directions, thus limiting the signal-to-noise ratio and imaging depth in practice. We present an overview of our new technology of focused shear wave beams, which aims to overcome these limitations by concentrating shear wave energy in TE near to the beam axis with vibration of a concave circular piston. Analytical modeling of focused shear wave generation and propagation is validated against measurements in gelatin phantoms. Results indicate that focused shear wave beams have relatively larger amplitudes and penetration depths compared to unfocused shear wave beams. Ongoing modeling and experimental efforts towards the measurement of elastic anisotropy, such as of skeletal muscle, using focused shear wave beams will be discussed.
Comparison of passive beamformers for isolating cavitation activity originating in the spinal canal
Authors: Frizado Andrew P.
Published: April 2023

Focused ultrasound application to the spinal cord, through the intact spine, is confounded by the presence of substantial prefocal cavitation, in the posterior soft tissue and musculature. When constructing cavitation images to localize and control intracanal cavitation, the prefocal cavitation zones dwarf the signals from the canal, destructing the localization ability of the imaging inside the sensitive cord tissue—even when conventional phase and amplitude corrections are applied. In this study, multiple beamforming formulations are investigated to mitigate the influence of prefocal cavitation on transvertebral cavitation imaging, while preserving the localization ability in the canal. The performance of a standard delay-and-sum-integrate beamformer (DAS) is compared to delay-multiply-and-sum-integrate beamformer (DMAS), and the DMAS algorithm is tested with a paired multiplicative compounding method (pDMAS) that leverages the dual aperture approach required for transvertebral focused ultrasound sonications. The focal point spread function of the beamformers in passive cavitation images (tint = 7 μs) were 7.9 × 2.2 × 1.3 mm (DAS), 6.9 × 1.7 × 1.1 (DMAS), and 6.5 × 2.9 × 1.7 mm (pDMAS) at 800 kHz. These beamforming approaches are evaluated for localization ability and clinical feasibility through cavitation imaging of prefocal and focal sources with in silico models and ex vivo human vertebrae.
Development of balloon-based seismology for venus through earth-analog experiments and simulations
Authors: Krishnamoorthy Siddharth , Bowman Daniel , Hough Emalee , Yap Zach , Wilding John D. , Jacob Jamey , Elbing Brian R. , Martire Leo , Komjathy Attila , Pauken Michael , Cutts James , Jackson Jennifer
Published: April 2023

Balloon-based seismology through the study of low-frequency seismo-acoustic signals (infrasound) has gained acceptance as a viable way to study seismic activity on Venus. Balloon-based barometers have the potential to detect and characterize atmospheric waves launched by venusquakes and volcanic eruptions while offering substantially longer instrument lifetimes in the Venus middle atmosphere, where temperature and pressure are significantly more benign (0–100°C, ∼1 atm) as compared to the surface (>460 °C, ∼90 atm). One of the major challenges in performing balloon-based seismology on Venus is the absence of ground-truth data for event identification and discrimination. To address this challenge, our activities are aimed at building a catalog of terrestrial balloon-recorded infrasound signals of geophysical provenance, using which signal predictions can be extended to Venus and the detectability of events can be analyzed. We will highlight our recently concluded Balloon-based Acoustic Seismology Study (BASS) flight campaign, which served as Earth-analog experiments for Venus balloon-based seismology. Data collected were used to validate seismo-acoustic simulation tools, which are being expanded to include the Venus atmosphere. These tools will used to generate predictions of infrasound signals from geophysical events on Venus. We will also provide perspective on directions for future instrument development for Venus balloon flights.
Extended high frequencies for fricative classification in conversational speech
Authors: Kharlamov Viktor , Brenner Daniel , Tucker Benjamin V.
Published: April 2023

The current study examines whether the information contained in Extended High Frequencies (EHFs) can improve random forest classification accuracy for fricatives in conversational speech. Prior phonetic research has investigated fricative categorization based on their acoustic characteristics, including spectral, temporal and amplitudinal measures. The spectral measures in these studies have largely been limited to frequency information below 8 kHZ. Only a few studies have examined the contribution of EHFs, energy exceeding 8 kHz. These studies have primarily focused on laboratory speech, so little is currently known about the role of EHFs in more spontaneous, conversational speech styles. Using a corpus of sociolinguistic interview speech from Western Canadian English sampled at 44.1kHz, we compare classification models with and without frequencies above 8 kHz. We discuss the influence of EHFs on the categorization of fricative identity, and share a cost-benefit analysis of sampling at higher frequencies for speech research corpora.
Effects of bilateral cochlear implants on vocal intensity control
Authors: Soleimanifar Simin , Aronoff Justin M.
Published: April 2023

Bilateral Cochlear Implants (BiCIs) can improve many perceptual tasks, including speech perception in noise, when compared to unilateral implantation. However, evidence suggests that BiCI users may perform worse on some vocal tasks, such as F0 production, than when using their better ear alone. This research aimed to determine if this detrimental effect on vocal control with BiCI devices extends to the control of vocal amplitude variations. Ten BiCI users were asked to produce a sustained vowel vocalization using both CIs and one CI separately. Their recordings were analyzed acoustically to determine long-term control of amplitude variations using the Variation of Peak Amplitude (vAm). The preliminary findings showed that using both CIs resulted in less control over vocal intensity for eight participants when compared to using one ear alone. The other two participants either showed no difference between the conditions or had a higher vAm with the unilateral ear than with the bilateral condition. The result suggests that BiCI use might detrimentally affect controlling long-term vocal intensity variation beyond any effects of unilateral CIs. Further investigation is needed to address how the vocal intensity control in BiCI users is affected.
Localization of an acoustic autonomous underwater vehicle using multi-channel back-propagation methods
Authors: Kukshtel Natalie , Lin Ying-Tsong , Gawarkiewicz Glen
Published: April 2023

Autonomous underwater vehicles (AUVs) are extremely useful tools for studying the acoustics of complex ocean environments due to their ability to detect environmental changes with greater spatial resolution than fixed moorings. During the New England Shelf Break Acoustics (NESBA) experiments in May 2021, an AUV system was deployed to collect acoustic data for investigating the local biological, physical, and geological oceanography. This acoustic AUV system was comprised of a modified REMUS 600 vehicle, a hull-mounted 3.5 kHz transducer, and a towed multi-channel hydrophone array. Along mission profiles where the AUV is fully submerged but too shallow for bottom-lock navigation, one challenge is accurate localization of the AUV. Localization was performed in post-processing using multi-channel back-propagation methods applied to AUV source signals received at mooring hydrophones in the NESBA network as well as ship-towed sound source signals received at the AUV-towed array. Uncertainty in the localization estimates due to spatiotemporal sound speed changes was investigated, and hydrophone mooring tilt angle was determined by minimizing the localization uncertainty. Following localization, this AUV acoustic data was used to investigate local seafloor sub-bottom properties and the acoustic effects of biological scattering layers and varying physical oceanography. [Work supported by the Office of Naval Research.]
Velocity estimation using a compact correlation velocity log
Authors: Blanford Thomas E. , Brown Daniel C. , Meyer Richard J.
Published: April 2023

Unmanned underwater vehicles require bottom-referenced acoustic navigation aids to maintain long-term positional accuracy without surfacing. When these platforms are small, they create new design constraints for acoustic navigation aids because of the limited available space and power. Traditional acoustic navigation techniques, such as Doppler Velocity Logs, are unsuitable for use on small platforms because of the power required to maintain adequate signal to noise ratio when they are scaled in size. A compact correlation velocity log (CVL) is an alternative approach that can meet the power, space, and accuracy requirements for an acoustic navigation aid on such platforms. This device uses a single projector, a sparse receive array, and estimates platform motion using a multi-dimensional fitting algorithm over an ensemble of 3 or more pings. This presentation will discuss the theory of operation, simulation, and experimental results for a 300 kHz compact CVL that is 4 × 8 cm2. [The authors want to acknowledge Lockheed Martin Rotary and Mission Systems for their financial support of this work.]
Adventures in uncertainty: A former consultant’s view of manufacture-driven acoustical testing
Authors: Raley Michael
Published: April 2023

Acoustical consultants commonly rely on laboratory testing of wall and floor/ceiling assemblies to inform their designs and to evaluate noise control solutions. Today, much of the available laboratory testing comes from manufacturers of noise control products. Laboratory tests are taken as indicative of assembly and product performance, but there is significant uncertainty inherent in the ASTM E90 and E492 test methods. When evaluating test results to design assemblies or compare products, this uncertainty is often given insufficient attention and test results are taken as de facto indicators of assembly performance. Manufacturers are faced with how to handle this uncertainty when deciding what to test, where to test, how to test, and ultimately what results to make public. Manufacturers are often accused of “cherry-picking” test data, but the reality is often more complicated than that. In this presentation, the author will discuss his experience working at product manufacturers and deciding what to test and what data to make public. The presentation will also look at some examples of how the uncertainty in laboratory testing could affect the outcome of the tests. Finally, the author will discuss other ways of presenting test data that aim to reduce some of the uncertainty and make it easier for acousticians to make good design decisions.
Parallel implementations of the fast nearfield method for continuous-wave and transient pressure calculations
Authors: Honer Jacob S. , McGough Robert J.
Published: April 2023

FOCUS, the “Fast Object-oriented C + + Simulator” (https://www.egr.msu.edu/∼fultras-web/), enables rapid calculations of continuous-wave and transient pressure fields generated by single transducers and phased arrays. FOCUS achieves small errors in relatively short computation times through memory-efficient calculations with the fast nearfield method, which converges exponentially. The fast nearfield method is also an embarrassingly parallel algorithm that supports further reductions in the computation time through hardware acceleration. Previous efforts to accelerate calculations with the fast nearfield method successfully implemented multithreading within multiple central processing unit (CPU) cores using OpenMP, and this capability is presently included with FOCUS. Prior success with OpenMP motivates ongoing efforts to further extend the functionality of FOCUS by interfacing the fast nearfield method to an NVIDIA graphics processing unit (GPU). To facilitate FOCUS calculations on a GPU, calculations with the fast nearfield method are implemented in CUDA for time-harmonic and transient pressure computations with each supported transducer shape. This combination achieves a significant reduction in the computation time compared to single-threaded execution. When evaluated on an NVIDIA 1670 GPU, the computation time is also approximately halved relative to the multithreaded OpenMP implementation. These results encourage further efforts to parallelize existing and future FOCUS routines.
Audio features of steelpans with few notes
Authors: Malloy Colin
Published: April 2023

Tenor steelpans are unusual, even among percussion instruments, in that all notes share a common surface. This physical coupling between the notes causes complex interactions between notes when activated. In an effort to better understand how these interactions work, we commissioned the building of three custom steelpans with one, two, and four notes instead of the typical 29. The one note pan has a single note in its standard position and the rest of the sunken bowl is empty. The two note steelpan adds a second note one octave higher. The four note steelpan further adds two notes a musical fifth higher. With the reduction in notes, the interactions are minimized and we can see how they affect the timbre of a full steelpan. In this paper, the results of audio feature extraction performed on these custom instruments is presented and compared with the audio features from a full range steelpan. Through this we gain insight into how octaves and fifths affect a note’s timbral characteristics and lead to the attributes of a full steelpan.
Sound barrier performance: Lab verus reality/new product development = lessons learned
Authors: Cook Craig
Published: April 2023

In this session, we'll explore the real world performance of sound barriers versus their lab testing along with lessons learned while developing a new upgraded reflective acoustic panel.
Multi model environmental noise projects—What are we doing?
Authors: Forschner Hans J.
Published: April 2023

For large-scale community projects the environmental noise engineers is charge to develop a noise model that can consist of various types of noise sources. The project may require the consideration of road, light commuter rail/commercial rail traffic, construction (stationary, moving) and operation commercial manufacturing. In North America, the consulting community uses various standards that are dramatically different in the detail of the noise emission characterization, frequency range and the noise propagation algorithms. The presentation discusses difference between TNM, FTA/FRA and ISO9613 and raise awareness of the underlying void of consistent standards in North America. The EU Noise Directive gave the European Acoustic Societies a push to developed a consistent set of standards. The variety of standards and methodologies was detrimental to modeling of END projects.
Influence of ground blocking on the acoustic phase variance in a turbulent atmosphere
Authors: Ostashev Vladimir E. , Wilson D. Keith , Hart Carl R.
Published: April 2023

A number of previous studies have analyzed the impacts of anisotropy and inhomogeneity on sound propagation in a turbulent atmosphere. However, these studies did not address the potentially important factor of ground blocking, namely the inhibition of buoyancy-produced velocity fluctuations by the ground surface. The current presentation accounts for this effect following the reference D. K. Wilson, “A three-dimensional correlation/spectral model for turbulent velocities in a convective boundary layer,” Boundary-Layer Meteorol. 85, 35–52 (1997). The temperature and shear-produced velocity fluctuations are not significantly blocked by the ground and are modeled as in the study by V. E. Ostashev and D. K. Wilson [Acoustics in Moving Inhomogeneous Media, 2nd ed. (2015)]. The resulting turbulence model is used to calculate the variance of the phase fluctuations for vertical and slanted sound propagation in the atmosphere. The calculations are done without the Markov approximation which might not be applicable for the largest turbulence eddies in the atmospheric boundary layer such as those due to buoyancy-produced velocity fluctuations. Theoretical formulations for the phase variance are compared with the data in a recent experiment involving sound propagation from a ground-based source to microphones installed at different heights of a 135-m tower.
Parabolic equation simulation of diffraction effects in a sound beam propagating through a flowing fluid
Authors: Tchatat Ngaha Daudel , Frøysa Kjell E.
Published: April 2023

Ultrasonic transit time difference flow meters are today industrially accepted for custody transfer measurements of oil and for natural gas. Such meters are currently planned to be used also subsea and in remote operations, where the calibration possibilities are few. In such applications the speed of sound measured by these meters will be a powerful input for estimation of density and calorific value of the flowing oil or gas. The ultrasonic transit time measurements in such meters are carried out in a flowing oil or gas, over a range typically between 6 and 40 in. For precise transit time measurements over such ranges, diffraction corrections may be of high importance. Diffraction effects for an acoustic beam generated by a uniform piston source and propagating through a flowing fluid are therefore studied numerically. The flow direction will be perpendicular to the propagation direction of the acoustic beam. The investigation is based on a narrow-angle three-dimensional parabolic equation. Effects both on amplitude and on phase will be presented.
Using machine learning to identify and assess cloud coverage
Authors: Blackburn Hannah , Vecchiotti Andrea , Vignola Joseph , Turo Diego , Ryan Teresa J.
Published: April 2023

This machine learning project is part of ongoing longitudinal long distance atmospheric acoustic propagation research being conducted at the East Carolina University Outer Banks campus in Wanchese, NC. The overall project seeks to connect changes in the atmosphere by taking concurrent acoustic and meteorological readings and relating them to differences in sound propagation. Wide angle images of the sky are used to correlate cloud cover with concurrent near-surface temperature gradient measurements. The camera is mounted on a mast that houses the temperature logger array. Images are imported, segmented, and labeled in MATLAB and used as both a training and test image set. The results of this project enable more accurate characterization of cloud cover. This information supplements knowledge of heat flux between ground and the atmosphere which in turn supports improved modeling of long distance sound propagation.
Horizontal-plane localization of a target in the presence of a distractor: Effect of onset asynchrony
Authors: Stellmack Mark A. , Sheft Stanley , Chadaga Mallika
Published: April 2023

Listeners localized a target in isolation and in the presence of a distractor. The target consisted of 10 10-ms Gaussian pulses (energy between 3–5kHz); the distractor was either a 100- or 500-ms narrowband (1–2 kHz) noise burst. The listener, with head unrestrained, was seated in the center of 36 loudspeakers spaced every 10 degrees on the horizontal plane and obscured by screens. On each trial, the target was played through a randomly selected loudspeaker. Listeners used a laser pointer to indicate target location. Pointer position was detected by infrared cameras and the response angle calculated. In separate conditions, distractor position was either fixed or randomized across trials, with target-to-distractor onset synchrony an additional parameter. The left-right component of responses was essentially unaffected by the presence of the distractor in any condition. With notable inter-subject variability, the front-back response component also showed little effect of the distractor. This absence of consistent effect of the distractor contrasts with previously reported work. The target and distractor in the present research, however, were generally more discriminable than in past studies, which likely mitigated at least some of the deleterious effect of the distractor on target localization ability.
Modelling the hydrodynamic behaviour of the cochlea: is the stiffness of the Reissner's membrane important for frequency selectivity?
Authors: Vermeulen Arthur , Knoll Henk
Published: April 2023

The cochlea contains two membranes, the Reissner's membrane and the Basilar membrane. In most models of the cochlea only the Basilar membrane is considered. The displacement of the Basilar membrane is crucial for stimulating the sensory cells within the cochlea. The omission of the Reissner's membrane is often justified because it is believed to be floppy, and it makes the calculation of the travelling wave on the Basilar membrane analytically possible. In the present work we have looked into the influence of the stiffness of the Reissner's membrane on the frequency selectivity of the Basilar membrane with a finite-volume model of the cochlea. Simulations are performed with a logarithmic distribution of the Basilar membrane stiffness. Each segment of the Basilar membrane oscillates with an increasing amplitude for a different frequency of the stimulus (the local resonance frequency) and shows the expected frequency selectivity. Our simulations indicate that the local resonance frequency does not change with the stiffness of the Reissner's membrane as long as the sum of the stiffness of the Basilar membrane and the Reissner's membrane remains the same. Consequently, the division of stiffness over both membranes has no impact on the frequency selectivity of the Basilar membrane.
A systematic review of measurements of real-world interior car noise for the “Cadenza” machine-learning project
Authors: Firth Jennifer L. , Cox Trevor J. , Greasley Alinka , Barker Jon P. , Whitmer William M. , Fazenda Bruno , Bannister Scott , Graetzer Simone , Vos Rebecca , Roa Gerardo , Akeroyd Michael A.
Published: April 2023

Interior car noise refers to the general noise generated by the engine transmission, the interaction between road and types, and weather conditions such as turbulent wind. For drivers or passengers with hearing loss, these can create especially challenging listening situations. The Cadenza Project is organising a series of machine learning challenges to advance signal processing of music for listeners with a hearing loss, and a key scenario in its first challenge is listening in a car to music in the presence of noise. To create enough machine-learnable training materials we need to simulate typical car noises rather than just use one particular recording. We are systematically reviewing the literature on real-world recordings to determine the range of parameters for these simulations. We searched Web of Science with the terms “(car noise, car noise interior, interior noise) AND (speed OR FFT OR spectr*).” A total of 126 studies have been found so far and 12 papers retained on the basis that a frequency spectrum for interior car noise was provided that was suitable for numerical analysis. Results will be presented.
How do perceptual benefits from musical experience compare with those from speech experience?
Authors: Shorey Anya E. , King Caleb J. , Stilp Christian E.
Published: April 2023

Acoustic consistency facilitates perceptual processing while acoustic variability challenges it. This is evident in perceptual interference tasks, in which listeners categorize a target word/pitch when produced by either a single talker/musical instrument or multiple talkers/instruments. Responses are faster and/or more accurate for single-talker (e.g., Stilp & Theodore, 2020 AP&P) and single-instrument conditions (e.g., Shorey et al., 2022 ASA). While patterns of results are parallel across domains, listening experience is not. Participants in speech tasks are experts at their native language, but in the music task the contribution of musical experience is unclear because Shorey et al. tested solely nonmusicians. This raises two questions: (1) does more musical training increasingly protect against timbral variability when making pitch judgments, and (2) how does musical expertise compare with speech expertise? To evaluate these questions, we tested native English speaking nonmusicians (<2 years of formal musical training), intermediate musicians (2–9 years), and experienced musicians (10 + years) in speech interference and music interference tasks. We predict that musical training offers resilience to variability, such that interference in the music task will decrease with increasing musical experience. We also predict correlated interference for advanced musicians (i.e., experts) across speech and music tasks. Results will be discussed.
Measuring the efficiency of listening effort
Authors: Winn Matthew B.
Published: April 2023

Listening effort is a commonly reported difficulty among those who have hearing loss. This project aims to operationalize the concept of effort precision, as the ability to engage or disengage mental resources at strategic times could be an important signature of a person’s capacity to guard against wasted effort. Stimuli were designed to simulate the situation of seeking clarification of a misperceived word or attending to specific information in a sentence. Some stimuli included verbatim repetitions (which would ideally elicit reduced effort) and others featured sentences with a masked word followed by a clear repetition (which would ideally evoke effort aimed only at the newly unmasked word). Pupillometry was used as an index of moment-to-moment changes in listening effort. Data showed pupil dilations linked in time with the unmasked word, enabling precise measurements of the efficiency of effort. Listeners with normal hearing displayed the ability to plan and exert effort at specific times while also reducing effort in situations where it was unnecessary. Conversely, listeners who wear cochlear implants generally did not display these efficient effort characteristics. These results highlight the need to expand the concept of listening effort beyond a “more” or “less” framework, toward a framework of efficiency.
Testing phenomenological auditory-nerve model predictions for selective inner- and outer-hair-cell dysfunction
Authors: Patra Madhurima , Sivaprakasam Andrew , Axe David , Heinz Michael G.
Published: April 2023

Sensorineural hearing loss (SNHL) effects on neural coding and perception have been largely associated with outer-hair-cell (OHC) dysfunction (e.g., reduced cochlear gain, reduced compression, broadened tuning). However, both inner-hair-cell (IHC) and OHC dysfunction occur in common hearing-loss etiologies, e.g., noise-induced and age-related (metabolic). Although IHC effects are largely ignored based on the insensitivity of audiograms to IHC loss up to 80%, the same selective IHC damage affects suprathreshold hearing (e.g., tone-in-noise detection, EFRs to periodic stimuli). Phenomenological auditory-nerve (AN) models are useful for studying neural-coding effects of SNHL, but their parametric control of OHC and IHC function (e.g., cohc and cihc parameters, Bruce et al., 2018) are designed based on data from animals with noise-induced hearing loss (OHC/IHC dysfunction combined). Although this approach has proven successful for OHC effects, testing of IHC-based effects has been largely indirect. Here, we compare model predictions to our previously collected AN-fiber responses to amplitude-modulated stimuli in animals with either carboplatin-induced selective IHC dysfunction or gentamicin-induced selective OHC damage to provide more direct testing of IHC and OHC effects. Model parameters were estimated from histology, ABR thresholds, AN-fiber rates, and spike-train statistical metrics (e.g., vector strength, discriminability, mutual information).
A comparison of perceptual training efficacy and trajectories in young and old adults
Authors: Birgitte Poulsen , Bohn Ocke-Schwen , Draxler Christoph
Published: April 2023

Current speech learning models propose that the ability for the reorganization of phonetic systems remains intact over the entire life span. This claim is well supported for adults up to the age of ca. 40 years, but empirical evidence on phonetic flexibility in mature learners is very scarce. We report on the first of a series of studies which examine seniors’ (age 60 plus) phonetic learning ability. Two age groups of native Danish participants (young: age 18–35, and old: age 60–75) took part in ten sessions which trained the perception of the English initial /s-z/ contrast, which is absent from Danish (with only /s/.) The training groups, as well as age-matched control groups, also took part in pre- and post-tests examining their perception and production of English initial and final /s/ and /z/. The results address questions concerning age differences in phonetic learning and in learning trajectories, as well as questions concerning allophone-specific versus phoneme-general learning, and the nature of the production-perception link in phonetic learning. [Research supported by a grant from the Independent Research AcoFund Denmark, grant DFF2 0132-00008B.]
Asymmetries in vowel perception align with focalization patterns, not peripherality: Acoustic evidence from Canadian French /e/ and /Ø/
Authors: Polka Linda , Masapollo Matthew , Menard Lucie
Published: April 2023

The question of whether asymmetries in vowel perception stem from peripherality (location in F1/F2 vowel space) or focalization patterns (formant convergence) was examined. Prior studies with Danish and Dutch listeners reported asymmetric perception of /e-Ø/ such that discriminating a change from /e/ to /Ø/ was easier compared to the reverse direction (/Ø/ to /e/). Acoustic analyses of test stimuli suggest that focalization patterns predict this asymmetry whereas a peripherality-based prediction fails. Although this interpretation is compelling, it is based on analyses of several vowel tokens produced by a single talker. To confirm the reliability of these patterns we obtained acoustic and electromagnetic articulography recordings of Canadian French /e/ and /Ø/ productions from a broader sample of talkers (n = 20): 400 vowels/10 productions per vowel. Acoustic analyses revealed a robust pattern for all talkers: F1 and F2 (also F1 and F3) were spectrally closer for /Ø/ compared to /e/, and /e/ was also more peripheral than /Ø/ in F1/F2 space. These data align with the earlier (single-talker) analyses and confirm that /Ø/ is a more focal vowel than /e/. We will also discuss articulatory analyses of these French vowel productions that focus on how vocal-tract constrictions relate to focalization and peripherality.
Multilingual spoken word recognition: A megastudy approach
Authors: Tucker Benjamin V. , Perry Scott J. , Nijveld Annika
Published: April 2023

Bilingualism research has primarily focused on the perception and processing of individual sounds or word learning. Many studies have investigated how bilingual listeners perceive sound contrasts that don't create lexical distinctions in their native language. There is substantially less research that has investigated how word-level properties impact L2 auditory processing. The present study examines how auditory lexical processing differs between monolingual and bilingual listeners with different language backgrounds. We collected lexical decision accuracies and latencies for 26,793 words and 9600 pseudowords from the Massive Auditory Lexical Decision database from native and non-native listener responses. We compare the language backgrounds of our 1028 listeners and group them into four groups: native speakers, early, early-late, and late bilinguals. We report the findings of an analysis investigating how language background and proficiency modulate lexical effects to understand how language background influences spoken word recognition. We find differences in the effects of lexical frequency, phonological neighborhood density, and phonological uniqueness point between the different listener groups. We discuss the impact of bilingualism in a word recognition task and how these results inform models of spoken word recognition and second language acquisition.
Phonetic learning and vocabulary knowledge in adolescents
Authors: Hopper Alissa , Heffner Christopher C.
Published: April 2023

Individuals who perform well on tasks that measure their abilities to learn non-native speech sounds tend to also perform well on language measures such as vocabulary tests. This relationship is not well understood but may be driven by increased literacy skills among individuals with stronger phonetic learning skills. However, relatively few studies have examined the changes in performance that occur during adolescence, a time in which critical vocabulary knowledge is amassed. This is an especially interesting developmental period because studies comparing adults and children show that adults often outperform children on measures of non-native speech sound learning. In the present study, we examine the changes in non-native speech sound learning abilities that occur during adolescence. Our preliminary data confirm previous findings which show that non-native learning performance tends to increase with age. We also explore vocabulary development as a correlate of this effect. Our preliminary data suggest that the correlation between non-native phonetic learning and vocabulary grows stronger with age during adolescence. These findings support the hypothesis that phonetic learning abilities continue to develop during adolescence and that this development is relevant to language outcomes in the adolescent population.
Optimizing wireless acoustic energy harvesting and communication with passive markers underwater
Authors: Bhardwaj Ananya , Allam Ahmed , Erturk Alper , Sabra Karim G.
Published: April 2023

To enhance functionality of Acoustic Identification Tags (AID), passive markers designed as landmarks for Autonomous Underwater Vehicles (AUVs) [Satish et al., JASA 149 (2021)], the development of an accompanying battery free active communication platform was explored [Bhardwaj et al., JASA 152, 4 (2022)]. This platform utilizes custom piezoelectric transducers impedance matched for broadband operation, enabling concurrent acoustic energy harvesting and fast backscatter communication [Allam et al., SPIE 31, 9 (2022)]. The combination of these active and passive devices can improve AUV localization and information transfer for specific applications such as short-range search missions or AUV homing and docking. The design of this platform for underwater operations requires a balance of parameters such as center frequency and piezoelectric element dimensions to achieve a high range of operation, power efficiency and data rates, while minimizing attenuation and spreading losses challenges. The design process for piezo selection, acoustic and electrical impedance matching, transducer casing design, and the experimental evaluation of the chosen 350 kHz design will be discussed. This approach was validated experimentally to quantify performance metrics such as the maximal range, data rates using various standard communication such as Frequency Shift Keying (FSK) and Amplitude Modulation (AM).
Low signal-to-noise ratio localization exploiting through-the-sensor in situ environmental information
Authors: Akins Franklin H. , Kuperman William
Published: April 2023

Drifting sensors/arrays typically may not have detailed information of the environment. A combination of modal-MUSIC [JASA Exp. Lett. 2(7), 074802 (2022) ] and synthetic aperture matched field processing [J. Acoust. Soc. Am. 150(1), 270–289 (2021)] provides a method to localize a weak source in a shallow water environment without a priori knowledge of the bottom geoacoustic parameters. The success of the method hinges on its ability to extract the bottom geoacoustic information from noise. The technique is relevant for low-frequency (<500 Hz) localization with a drifting vertical line array. Localization of a quiet source without a priori geoacoustic information is demonstrated on data from the SWellEx-96 experiment. [Work supported by the Office of Naval Research.]
Subjective success of exterior glazing with both a light and heavy hand
Authors: Myers Joseph W. , Huey Michelle
Published: April 2023

The subjective success of the isolation of exterior noise depends greatly on the nature of the site noise, the use of the isolated space, and the client’s expectations. The architectural solution must respond to all of these factors, as well as budget and aesthetics. In recent years, Kirkegaard has completed several projects in which glazed walls separate a performance or rehearsal space from an urban or suburban exterior. Solutions have ranged from simple to “heavy-handed,” with a varying degree of subjective success. This paper offers a range of case studies, including situations where a significant retreat from “heavy-handed” solutions was subjectively successful and one situation where a modest retreat from “heavy-handed” solutions was not subjectively successful.
Automated region of interest placement on cervical ultrasound images for assessing preterm birth risk
Authors: Zuo Jingyi , McFarlin Barbara L. , Simpson Douglas G. , O'Brien William D. , Han Aiguo
Published: April 2023

Spontaneous preterm birth (sPTB) is one of the leading causes of infant morbidity. Medical interventions can prevent death caused by preterm birth if the risk is predicted at early stages. Quantitative ultrasound (QUS) is found valuable for predicting sPTB risk with a limitation of requiring a medically trained image analyst to manually draw a region of interest (ROI) on the cervix of a B-mode ultrasound image. An automated ROI placement algorithm was designed and trained to reduce the reliance on human annotations. The algorithm utilized a deep neural network with an optimized U-Net architecture to locate cervical tissues. A total of 8670 ultrasound images with sonographer-drawn ROIs were used for algorithm training and testing, followed by several postprocessing steps to yield the final ROIs. Quantitative comparison between algorithm-generated and sonographer-drawn ROIs yielded an average pixel accuracy of 96% and a dice coefficient of 88%. In addition, the QUS’s attenuation coefficient (AC) and backscatter coefficient (BSC) obtained from the algorithm-generated ROIs were highly correlated to those obtained from the sonographer-drawn ROIs with a Pearson correlation coefficient of 0.93 and 0.85, respectively. The results support the feasibility of automating QUS imaging for sPTB risk assessment. [Work supported by NIHR01HD089935.]
The tradeoffs between grating lobes and larger array pitch using null subtraction imaging
Authors: Gardner Mick , Oelze Michael L.
Published: April 2023

Null Subtraction Imaging (NSI) is a new beamforming technique for producing B-mode images that results in high spatial resolution and low computational cost compared to other high-spatial resolution imaging techniques. Previous work has demonstrated that in addition to a narrow main lobe and low side lobes, NSI can also reduce or mitigate grating lobes. Grating lobes can appear when the wavelength of ultrasound is larger than the pitch of the array and these grating lobes can result in imaging artifacts. Lower grating lobes on a larger pitch array could allow larger linear arrays for abdominal imaging with lower element count. Experiments were conducted to quantify the tradeoff between grating lobe levels and pitch size when using NSI. NSI was able to reduce grating lobes by up to 19dB with an element pitch of five times the wavelength. The effects of the DC offset (a tunable parameter of NSI) on grating lobe reduction were also testedand found that NSI with a lower DC offset provides greater reduction in grating lobes, with up to 40dB reduction. The level of grating lobe reduction versus the depth of a target was also testedand found a slight decrease in grating lobe reduction at greater depths.
Delivery of sirolimus with intravascular ultrasound to prevent vascular restenosis
Authors: Su Xiaoqian , Ang Huiying , Illinadala Uday , Yeo Khung Keong , Kwan James
Published: April 2023

Restenosis is the re-narrowing of arteries. It typically occurs after angioplasty treatment for peripheral artery diseasesand results in the need for invasive surgical treatments or amputation of the limb. Sirolimus is a known anti-restenosis drug, yet it requires long exposure time in the artery despite being quickly inactivated in blood. As such, there is a need for a targeted drug delivery methodology to promote slow-releasing sirolimus drug delivery vehicles. Our previous work suggested that sirolimus can be loaded into sound sensitive microparticles (SSMPs) comprised of PLGA. Here, we seek to determine if a bespoke intravascular device (IVUS) can deliver SSMPs to the arterial wall of a porcine artery in vivo. In this study, porcine arteries of three pigs were occluded by a balloon on the IVUS device distal to the treatment site, while drug loaded microparticles were injected through a sheath prior to ultrasound emission to facilitate uptake. We observed that the presence of SSMPs was larger in the arterial walls compared the blood and untreated arteries. The IVUS device provided a marginal increase in SSMPs in the treated arteries for most of the pigs. Thus, the in vivo studies suggested that the IVUS parameters were not yet optimized.
The subharmonic resonance of lipid-encapsulated ultrasound contrast agents
Authors: Yusefi Hossein , Helfield Brandon
Published: April 2023

A salient feature of ultrasound contrast agent echo is their subharmonic response, a property that can be exploited for diagnostic contrast imaging. Here, we aim to explore the subharmonic behavior, specifically the subharmonic resonance, of two identical lipid-encapsulated microbubbles in close proximity to each other (center-to-center h = 6–16 μm) using finite element modeling. We simulated the subharmonic resonance response for bubbles (R0 = 0.5–1.5 μm) driven with 10 or 20 cycle tone bursts from 6 to 18 MHz under a peak negative pressure from 40to 180 kPa over a range of initial phospholipid packing values (σ0 = 0–0.01 N/m). Our results demonstrate that for increasing pressure, the transmit frequency at which the peak in subharmonic response is observed shifts monotonically towards higher frequencies (1–10%) for bubbles close to their buckling point, while the opposite trend occurs for bubbles with less dense initial packing (1–15%). For intermediate values of initial packing, a two-stage response is observed whereby the transmit frequency first decreases and then increases (5–9%) with increasing pressure. These results have implications in subharmonic-based diagnostic imaging techniques.
Delayed subharmonic response of a phospholipid-shelled ultrasound contrast agent: Effect of temperature and protein concentration
Authors: Kaushik Anuj , Menon Surabhi , Shekhar Himanshu
Published: April 2023

The subharmonic response of ultrasound contrast agents (UCAs) is important for imaging and therapy. Therefore, factors influencing the temporal evolution of subharmonic signals should be elucidated. We evaluated the influence of temperature (25°C and 37°C) and protein concentration in the fluid (0.5% w/v at 25°C and 37°C) on the subharmonic response of Definity, a phospholipid-shelled UCA. Definity was diluted to 106 microbubbles/ml and sonicated at 2 MHz frequency, 50 cycles, and 470 kPa peak rarefactional pressure. The subharmonic response demonstrated striking qualitative and quantitative changes with time. At 25°C, a delayed subharmonic onset was observed. The subharmonic signal appeared after 28 min, peaking at 18dB above the baseline. At 37°C, the subharmonic signal appeared immediately but it peaked (5 dB increase) after 52 min. In the presence of dissolved protein, the subharmonic signal appeared at 16 min at 25°C and at 4min at 37°C. The signal peaked at 24 dB and 10 dB above the baseline at 25°C and 37°C, respectively. These observations underscore the need to standardize acoustic measurements and may have implications for subharmonic imaging, non-invasive pressure sensing, and cavitation detection.