bluuebunny/crossref_metadata_2025 huggingface dataset:
Acoustic properties of vocal emotions in American English and Mandarin Chinese
Authors: Wang Fenqi , Wayland Ratree
Published: April 2023

Previous studies have indicated that different vocal emotions in American English and Mandarin Chinese have distinct acoustic profiles, but the acoustic profiles of vocal emotions have not been established for each language. This experiment analyzes recorded sentences produced in five emotions by 10 native English speakers and 10 native Mandarin Chinese speakers from a novel emotional speech database (Zhou et al., 2021). To better understand the acoustic characteristics of the emotional utterances in both languages, this study used the feature extraction toolkit openSMILE to extract 6373 features (Schuller et al., 2016). Principal component analysis was applied to the extracted features for feature selection. Linear mixed-effects regression models were performed to determine the effect of emotions on the selected features. Bayesian multinomial logistic regression models were performed to examine the effects of acoustic features on emotions. The results suggested that American English and Mandarin Chinese exhibit different acoustic patterns of vocal emotions, but some features, particularly pitch-related features, are used by both languages to express vocal emotions. However, pitch variation may be more restricted in the vocal emotions of Mandarin Chinese relative to American English.
Vocal level and vocal effort variability across phrase types
Authors: Cantor Cutiva Lady Catherine , Berardi Mark , Gundry Sarah , MacDonald Hannah , Hunter Eric J.
Published: April 2023

Vocal effort is the most common symptom that in patients with voice disorders and decreasing vocal effort is often a therapeutic goal. Previous studies indicate that a vocal effort goal can elicit voice production with very similar acoustic parameters. The purpose of this study is to clarify the effort and acoustic parameter dependencies on different types of phrases elicited with different goals. Three types of speech (automatic, read, structured spontaneous) were elicited at using three communication goals (confidential, conversational, raised) with vocal effort quantified using a Borg CR100 scale. Participants’ vocal level reliably changed between the three elicited communication goals. Further, there was some trending differences depending on the length and type of speech. Further details will be presented. The results indicate the utility of the Borg CR100 in tracking effort in voice production that is repeatable with respect to vocal level (dB). Additional acoustic parameters as well as speech differences will be discussed.
Gender, but not speech material, affects extended high-frequencylevels in the speech spectrum
Authors: Delaram Vahid , Miller Margaret , Ananthanarayana Rohit M. , Stecker G. Christopher , Buss Emily , Monson Brian B.
Published: April 2023

Current evidence suggests extended high-frequency (EHF) speech cues support speech perception. Audibility of these cues likely depends on speech spectral levels at EHFs. These levels may vary across genders and different speech materials. In this study, we investigated the effect of talker gender and speech materials on EHF levels in speech. A group of 30 (15female) native speakers of American-English was recruited to participate in this study. A three-minute spontaneous narrative was recorded for each participant along with a subset of the Bamford-Kowal-Bench (BKB) sentences. An ERB-scaled long-term average speech spectrum was calculated for the narrative and for the BKB sentences for each subject. Linear mixed-effects models were used to test intersubject and intrasubject variability in 8 EHF ERB bands. There was a significant effect of gender with female EHF levels ∼4 dB higher than male EHF levels. Within-subjects comparison of BKB sentences and narratives revealed no significant difference in EHF levels between speech materials. These findings highlight the possibility that EHFs could play a more prominent role in female speech perception than male speech perception, and suggest that EHF levels are relatively stable across speech materials for a given talker. [Work supported by NIH under Grant No. R01-DC019745.]
Prosodic variation and rich linguistic environments in a preschool setting
Authors: Thorson Jill C. , Nesbitt Kimberly
Published: April 2023

Children require rich linguistic environments (RLEs) to support their development in early education settings (Bratsch-Hines et al., 2019; Justice etal., 2018). RLEs are defined by high-quality language, teacher tone (prosodic/fundamental frequency-f0 variation), and interactions between the teacher and children (increased turn-taking, contingent responses, open-ended questions) (Jones & Rowland, 2017). As we support enhancing the quality of interactions, we lack a quantifiable way to assess teacher language to provide clearer feedback. Our aims are (1) to quantify the measures used to assess the quality of teacher language, (2) to examine teacher prosodic variation across a typical day, and (3) to explore any connections between teacher (quality) language and prosody. Audio data were recorded from preschool classroom teachers (teachers of children aged 3 to 4-years-old; n = 5 to date). Each site had two days of recording, 4 to 8 hours per day. Teachers completed a background survey and reported a log of daily activities. The recordings are transcribed to analyze language and speech: measures of f0 variation, types of open-ended questions, word usage diversity, number of turns taken between the teachers-students, and presence of contingent responses. Data from this study help us to understand RLEs and provide a coding system to systematically capture teacher language in a more nuanced manner.
Within- versus between-speaker acoustic variability in Thai
Authors: Lee Yoonjeong , Kreiman Jody
Published: April 2023

This paper continues our studies of acoustic variability in voice between and within speakers. Previous work indicates that acoustic variability is characterized by the balance between high-frequency harmonic and inharmonic energy in the voice (measured using cepstral peak prominence) and by formant dispersion, regardless of the speaker’s sex, native language, or speaking style. Our recent investigation of the language effect on voice variability surveyed three languages, English, Korean, and White Hmong, which form an organized subset with respect to their linguistic use of F0 and the phonological status of phonation quality. The cross-linguistic comparisons revealed a second tier of language-specific variability that reflects features of the phonology of each language. The present paper adds a tone language, Thai, to the mix. Samples of read speech from fifty Thai speakers (33F, 17M) were evaluated as in our previous studies. Results revealed that variability in Thai voices is primarily accounted for by the same biologically relevant measures observed globally, and further shaped by the language-specific use of F0. These data further support our hypothesis that acoustic variability in voice is governed first by biological factors, secondly by language-specific, cultural factors, and finally by idiosyncrasies of an individual’s anatomy and personal speaking style.
Individual differences in acoustic variability and perceptual sensitivity to subphonemic variation
Authors: Harper Sarah
Published: April 2023

Individual differences are robustly attested in both speech production and perception, with interspeaker variation in production frequently observed in the same domains in which extensive variation is observed across listeners in perception. This study extends existing research by examining whether the relationship between production variability and perceptual sensitivity previously observed for vowels (e.g., Perkell et al., 2008; Franken et al., 2017) is also observed for consonants. 55 speakers of American English completed two online tasks designed to evaluate individual differences in the production and perception of /s/ and /ɹ/: a sentence production task and a 4IAX perceptual discrimination task. Preliminary comparison of acoustic variability measurements from the production task and response accuracy measurements from the perception task suggest that individual differences in these two domains are sometimes, but not always, related across speakers. Specifically, production variability and perceptual sensitivity were correlated for phonologically meaningful acoustic dimensions in the liquid phoneme /ɹ/, but not for any measured dimensions in the fricative phoneme /s/.
Gemination variation in three varieties of regional Italian
Authors: Miatto Veronica , Leon Amber , Rosales Tia , Stephen Kaitlin
Published: April 2023

Consonant gemination in Italian is phonologically distinctive, being acoustically realized with consonant closure duration and duration of the preceding vowel as primary cues. Southern varieties of Italian have been claimed to geminate more than Northern varieties. The purpose of these study is to analyze variation in gemination in two Northern varieties of Italian (Veneto Italian and Friuli-Venezia Giulia Italian) and Neapolitan Italian, spoken in the South. Moreover, generational variation will be analyzed for Venetian speakers. The study involved 40 speakers: 10 young speakers per region and 10 older speakers from Veneto. The speakers read aloud bisyllabic Italian words with voiceless stop geminates or singletons. Results show that there is no significant difference in gemination between younger (VY) and older Venetians (VO). This is surprising, as VO are more proficient in Venetian, a non-geminating language. Moreover, while VY and Friulian (F) speakers geminate similarly, a significant difference was found with how Neapolitan (N) speakers geminate, but not on whether N speakers geminate more than VY and F speakers. In fact, while VO and F geminate by lengthening the consonant closure more than shortening the preceding vowel, N speakers appear to shorten the preceding vowel much more than lengthening the consonant closure.
The status of lexical stress in understudied Kabyle Tamazight-Berber: “Acoustic evidence from Kabyle dominant speakers.”
Authors: Gaoua Dehbia
Published: April 2023

Until now, the classification of the prosodic systems of some languages (including Berber languages) is not conclusive and open to alternative interpretations. The question is: are these languages better classified as lacking stress or more controlled and systematic studies of these languages are needed? This study asks three main questions: (1) Is there lexical stress in Kabyle?, (2) what are the acoustic properties that manifest stress (if it turned out “it exists”)? and (3) which syllable in the word is prominent? Results from a closely controlled acoustic production study of 6 male Kabyle-native speakers, showed some evidence of lexical prominence in root words, which was manifested by intensity, duration (for vowel /æ/), and vowel quality (higher and more peripheral prominent syllable for /æ/ vowels). Louder, and higher and more peripheral vowels were observed in initial syllables while longer vowels (/æ/) were found in penultimate syllables. Surprisingly, based on the present data we did not see strong evidence of F0 being a meaningful correlate; however, we observed acoustic patterns consistent with an enhancement of the initial syllable corresponding to the focus condition, which led us to suggest that the pitch results looked like an intonational pitch accent that is location-sensitive. Implications and further work are discussed in the paper.
Reducing ambiguities in single-hydrophone matched-field processing by exploiting source motion
Authors: Cheney Margaret , Kirsteins Ivars
Published: April 2023

Matched-field processing for localizing an underwater acoustic source in range and depth from power-spectrum measurements obtained at a single hydrophone receiver often suffers from high side-lobes and ambiguities when the signal is narrowband or signal bandwidth is small. In this paper we review how source motion can be utilized to reduce side-lobes in depth and range via an incoherent synthetic-aperture-like approach and explain the mechanisms responsible for side-lobe reduction relative to the height of the main-lobe by using a normal-mode expansion for the pressure field. We also derive an approximation for the depth main-lobe width when the true source range is known for the ideal rigid-waveguide case. Numerical results are presented corroborating the analytical analysis along with some matched-field localization ambiguity surface examples for (a) an ideal shallow-water waveguide with a pressure-release top boundary and a rigid bottom boundary and (b) a more realistic shallow-water Pekeris environment, to demonstrate how side-lobes and ambiguities are reduced when source motion is exploited in the matched-field processing.
Active sonar detection with acoustic spiral waves: experiment and modeling
Authors: Bisbano Michael A. , Brown David A.
Published: April 2023

Active spiral-wave active localization is a technique for determining location of acoustic targets [after Dzikowicz et al., JASA 146, 4821–4830 (2019)], which relies on measuring the phase difference between a reference and spiral wavefronts. This research presents a monostatic model of spiral detection and tracking for multiple targets in sparse noise limited environments. Simulation and experimental results from an acoustic spiral wave beacon in a small underwater test tank will be presented. Results show good agreement to resolve targets in horizontal and vertical dimensions with a compact aperture. [Work supported by ONR 321MS.]
Creating acoustic spiral waves with quadrature and tertiary phase-biased dipoles
Authors: Jackson Avery A. , Brown David A.
Published: April 2023

Acoustic spiral waves have been demonstrated by exciting orthogonal modes of vibration in cylinders with just one electroacoustic transducer [J. Acoust. Soc. Am. 132(6) (2012)]. Applications including navigation, active sonar, and imaging are emerging. We demonstrate several practical engineering approaches to create constituent signaling with either quadrature or tertiary phase bias to excite spiral waves and compare their effectiveness. Approaches using CODECs, DSP, and flip flops are designed and characterized then tested on underwater transducers in realistic operating conditions. Tradeoffs of source level, effective coupling, bandwidth, and radiation patterns are summarized. [Work supported in part by BTech Acoustics LLC and ONR 321MS.]
Data-model comparison of elastic target scattering for a shallow water sonar system for buried UXO detection
Authors: Philtron Jason , Brown Daniel C. , Johnson Shawn , Dalton Kyle S. , Goehle Geoff , Blanford Thomas E.
Published: April 2023

Successful buried unexploded ordnance (UXO) detection in shallow water (<3 m) has been demonstrated using a sonar system deployed from a shallow-draft surface vessel. Data was collected over several years and during different seasons in a freshwater reservoir near Howard, PA, USA. The target test field contains a variety of science (e.g., sphere, cylinder) and other objects. Previously, a point-based sonar scattering model that simulates calibrated time-series sonar data due to sediment surface and volume scattering effects was shown to provide simulated data of the environment. Recently, object scattering models have been added to the simulation. The results of a model-data comparison of objects in the environment will be presented. Realistic simulation results containing objects will increase understanding of detection capability in different geometries (e.g., depth) and environments (e.g., sediments, layering).
Array invariant-based range-only target motion analysis for ship noise measured by two vertical line arrays in shallow water
Authors: Sul Hoseok , Jo Moon Ju , Song Taek Lyul , Choi Jee Woong
Published: April 2023

A novel approach for underwater acoustic localization by using passive line array sonar will be proposed in this talk. In the case of the received signal having a finite pulse duration, the target location can be easily estimated using the time-difference-of-arrival (TDOA) method between sensors. However, it is difficult to use the TDOA method for signals that exist for a relatively long time, such as ship noise. An array invariant method has been proposed to measure the source-receiver distance, but it does not accurately estimate the target location. In this talk, target localization will be performed with the range-only target motion analysis method using non-linear target tracking after estimating the target range by the array invariant method. The proposed method is tested using the ship noise of the R/V Onnuri measured by two vertical line arrays during the Shallow-water Acoustic Variability Experiment (SAVEX-15), and the result will be discussed in this talk. [This research was supported by the Ministry of Oceans and Fisheries of Korea (PM63010, 2022).]
Low-frequency holographic signal processing for moving sources separation in shallow water waveguide
Authors: Pereselkov Sergey A. , Kuz'kin Venedikt , Ladykin Nikolai , Sotnikov Dmitry , Pereselkov Alexey
Published: April 2023

The results of numerical modeling of the interferometric signal processing for broadband sources (200–300 Hz) moving in shallow water waveguide is presented in the paper. Each source creates in receiver point a stable interference pattern of the intensity distribution (interferogram) in the frequency-time domain. The 2D Fourier Transformation (2D-FT) is applied to analyze the superposition of several interferograms of the sources moving in waveguide. 2D-FT of interferogram—hologram is superposition of the holograms of the sources moving in waveguide. The source hologram allows to coherently accumulate the sound intensity of the source interferogram in a relatively small area as focal spots. The sources can be separated when the sources holograms spots are not overlapped and thus can be filtered. The information about each source is in separated hologram. So, separated hologram allows to estimate source range, its velocity and direction (S. Pereselkov and V. Kuz’kin, JASA 151(2), 666–676). Within numerical experiment the separation of three noise sources with different intensities moving in different directions with different velocities is considered.The error of estimation of parameters of each source is used as a criterion of resolving efficiency of proposed method. [This study was supported by RFBR 19-29-06075, МК-4846.2022.4.]
Quiet uncrewed surface vessel assesses fish avoidance of motorized survey ships in the Great Lakes
Authors: Evans Thomas M. , Rudstam Lars , Sethi Suresh A. , Barnard Andrew , Koproski Scott R. , Hanson S. D. , Yule Daniel L. , Warner David M. , Wells Susan E. , Turschak Benjamin , Farha Steven A. , O'Brien Timothy P. , McDonnell Kevin N. , Watkins James M. , Dufour Mark R. , Dieter Patricia M. , Kocher Erik , Roberts James J. , Senczyszyn Steven , Esselman Peter
Published: April 2023

Acoustic surveys of fish are a foundational component of many fisheries monitoring programs, including surveys in the Great Lakes. These surveys are conducted with traditional crewed and motorized vessels, but fish avoidance of these types of platforms has been reported in multiple studies, potentially biasing estimates. A quiet uncrewed surface vessel, Saildrone, was equipped with a 120 kHz Simrad EK80 transducer and deployed in Lakes Huron, Michigan, and Superior in the summers of 2021 and 2022. The drone was then overtaken by numerous motorized vessels using transducers with the same frequency. The average target depth, target strength, and nautical area scattering during overtakes were compared. We looked for a fish behavioral response with General Additive Models using distance from the Saildrone to the vessel as the predictor. We also compared the effectiveness of acoustic surveys from each platform with analyses of variances over 2 km sections of the overtake. Fish showed a limited response to approaching vessels, and acoustic estimates of fisheries relevant measures were similar between Saildrone and motorized vessels. Findings from this work will inform interpretation of acoustic data in the Great Lakes and provide the largest scale testing of fish avoidance to acoustic surveys to date.
Lessons in large-sample laboratory sound transmission loss testing
Authors: Shafer Benjamin M.
Published: April 2023

Thousands of laboratory sound transmission loss tests, in accordance with the ASTM International Test Method E90, reveal some trends that challenge multiple aspects of building sound isolation. Some notions about sound transmission through building assemblies are accepted industry-wide that these current studies bring into question. The applicability of the Sound Transmission Class (STC) rating system also becomes challenging when observing trends in large and varied data samples. From preliminary small-sample studies to measure uncertainty across laboratories to large-sample observations of assembly test data, this presentation offers guidance for both the development of standards in the building sound isolation industry and for education in the building design process.
Sound rating of catalog air handlers
Authors: Knight Derrick P. , Lind Stephen J.
Published: April 2023

Publishing sound power data for air handlers involves providing data across millions of variations related to operating conditions and unit configurations. AHRI 260 provides both the measurement and modeling guidelines used by most HVACR companies in the United States. However, many building designers are unfamiliar with the details of how a finite set of measurements taken in accordance with AHRI 260 becomes published sound rate data used to design quiet buildings. A case study based on a real product release is used to clearly define this process.
Dangers of applying fan manufacturer data to equipment sound ratings
Authors: Bauch Paul F. , Howard Roger L.
Published: April 2023

Equipment sound ratings are a valuable tool for consulting engineers; however, the basis of these ratings is not always clear. Custom AHU manufacturers most commonly utilize fan manufacturer data in accordance with AMCA 301 Methods for Calculating Fan Sound Ratings from Laboratory Test Data, and the AMCA 311 Certified Ratings Program. This paper will compare fan manufacturer data to test data collected in accordance with the mapped sound rating approach detailed in AHRI Standard 260, discuss possible sources of error in applying this data, and propose a best practice when comparing ratings from multiple custom AHU suppliers.
Heptuna: The most outstanding subject
Authors: Moore Patrick
Published: April 2023

One of the best experimental collaborators I have ever worked with was HEP, a bottlenose dolphin (Tursiops truncatus). HEP was instrumental in leading the way for subsequent dolphin investigations. In the first study on dolphin sound localization, HEP was the willing subject [D. L. Renaud and A. N. Popper, “Sound localization by the bottlenose porpoise Tursiops truncatus,” J. Exp. Biol. 63, 569–585(1975)]. Thus began a series of critical experiments that set the foundations of cetacean hearing and echolocation. I had the pleasure to partner with Whit Au and HEP to explore the many aspects of dolphin hearing and echolocation. HEP carried the experience of his training and testing to new experiments. If he saw just one response manipulandum, he seemed to know it was a go/no go response requirement, or if two, a forced choice response. HEP was the first animal to use “jaw phones” to test hearing, and interaural time and intensity differences. He demonstrated he could control his echolocation clicks, he provided measures of his transmitting and receiving beam patterns, and much more. Unfortunately, we lost HEP in 2010 after a 40-year history with the U.S. Navy Marine Mammal Program.
The life semi-aquatic: Harbor seal sprouts and milestones in marine bioacoustics
Authors: Reichmuth Colleen
Published: April 2023

Harbor seal Sprouts (Phoca vitulina) spent 31 years contributing to a wide variety of scientific studies, supporting educational opportunities for students of all ages, and training generations of future scientists, veterinarians, animal care specialists, and teachers. He participated in research projects on associative learning, sensory biology, communication, and physiology, but was perhaps best known for his contributions to marine mammal acoustics. His good-natured cooperation advanced knowledge of sound production and ontogeny, revealed the true amphibious hearing capabilities of seals, and improved our ability to predict the harmful effects of human-generated noise. Sprouts contributed to 34 empirical publications (thus far), many reviews of marine mammal cognition, communication, and sensory biology, and national policy guidelines for marine mammals. Sprouts taught us many things, but perhaps the most important lesson is about the value of individual subjects. While science and conservation often happen at the level of populations, species, and ecosystems, Sprouts showed us that one individual matters and can have a significant impact. He reminds us to find delight and discovery in this complicated, extraordinary life in science.
Temporary threshold shifts in Boris the bottlenose dolphin (Tursiops truncatus), varying noise duration and intensity
Authors: Mooney T. Aran , Nachtigall Paul E.
Published: April 2023

There is much concern regarding increasing noise levels in the ocean and how it may affect marine mammals. Early on, there was little information regarding how sound affects marine mammals and no empirical data on the relationship between noise intensity and exposure duration. Working with Boris the bottlenose dolphin, Tursiops truncatus, we explored the effects of octave-band noise, and sonar signals on odontocete hearing and noise-induced temporary hearing threshold shifts (TTS). Sound pressure levels (SPLs) and exposure durations were varied to measure the effects of exposure duration and amplitude. Hearing thresholds were initially measured behaviorally, and later using auditory evoked potentials before and after sound exposure to track TTS and recovery. These efforts showed that threshold shifts were not linear but rather shorter sounds required greater sound exposure levels to induce TTS; a contrast to some early published literature. Further, sound exposure levels of sonar signals required to induce TTS were high, supporting the notion that relatively short sounds must be of relatively high intensity to induce threshold shifts. From these data and this remarkable animal, a novel algorithm was written that predicts the physiological effects of anthropogenic noise if the intensity and duration of exposure are known.
Learning from Freja the harbor porpoise to appreciate movements as an important behavioral readout to understand echolocation-based target discrimination
Authors: Lee Wu-Jung , Ladegaard Michael , Buck John R. , Madsen Peter T. , Beedholm Kristian , Tyack Peter L.
Published: April 2023

Toothed whales routinely discriminate and select prey via echolocation. Over a decade, the harbor porpoise Freja in Fjord and Bælt, Kerteminde, Denmark participated in a series of target discrimination experiments involving metal objects. Different from experiments in which the subjects were constrained to be stationary, Freja’s free and voluntary movements offered insights into the tightly coupled nature of acoustic sampling and movements in echolocation-based target discrimination. Compared with observations from wild animals with unknown prey, the controlled experimental task and stimuli made it possible to interpret her behavior based on predictable target echo features. Here, we test the hypothesis that an echolocating animal plans its movement based on prior echo returns to gather better target discrimination information. We trained Freja to approach and select a sphere against a spheroid in a two-alternative forced-choice discrimination task, and show that her performance and movement trajectory varied depending on the aspect ratio and presentation angle of the spheroid. Consistent with our hypothesis, we further show that Freja’s movement patterns were likely driven by echo information received earlier during the approach that is correlated with the discrimination difficulty. These results highlight movements as an important behavioral readout of the dynamic, closed-loop sensorimotor feedback in echolocation. [Work supported by ONR.]
Celebrating the Navy’s sea canaries: The lives and bioacoustic research accomplishments of white whale (Delphinapterus leucas) collaborators
Authors: Schlundt Carolyn E.
Published: April 2023

The Navy Marine Mammal Program has engaged many different species over the years to accomplish missions of finding and retrieving objects in the marine environment, and asset protection, but perhaps none has been so engaging as the white whale, or beluga (Delphinapterus leucas). At a time when the Cold War focus moved to the frigid waters of the Artic, the Navy needed echolocating, deep diving, cold-water experts. Enter, the belugas. Unique because of their all-white color, lack of a dorsal fin, and extensive repertoire of bird-like vocalizations (hence the moniker “sea canary”), the group with their naturally curious, gregarious demeanor and malleable melons, also quickly began to grace the pages of scientific journals and book chapters with their acoustic capabilities for a period of approximately 30 years. Most notably among them were a female named MUK (after the Inuit word muk tuk for whaleskin and blubber) and a male named NOC (after the tiny biting summer flies known as no-see-ums). Together, these two whales expanded our knowledge of marine mammal bioacoustics and physiology with their collaboration on projects related to detection, hearing, echolocation, nasal pressure, sound production, human-speech mimicry, net-aided foraging, diving physiology, stress hormones, reproduction, growth, and development.
A legacy of excellence: SAY’s contributions to bioacoustics research at the Navy Marine Mammal Program
Authors: Christman Katie A.
Published: April 2023

The dolphin SAY is considered a jack-of-all-trades in marine mammal science. This comes as no surprise as her mother was one of the five dolphins deployed to Cam Ranh Bay, Vietnam as part of the Navy’s first deployable marine mammal system. SAY was born in 1979 and began participating in research from birth; she was the first dolphin to have her caloric intake and weight tracked as a calf into adulthood, and while carrying her own calf in 1991. In her early years, she participated in cutting-edge studies using high-speed video endoscopy to better understand dolphin click production. She later participated in echolocation vigilance tasks that spearheaded our understanding of dolphin cognitive abilities focusing on duration and the effects of anthropogenic noise. During this same time, she diligently contributed to projects that revolutionized our understanding of dolphin biosonar and its relation to perception and auditory system neurophysiology. SAY will be remembered by her charismatic personality and her 38 years of service to science and the United States Navy. Her daughter continues to carry out her legacy working for the Navy’s fleet mine-hunting system.
A mammal for all seasons: Contributions from the bottlenose dolphin TRO to bioacoustics research at the US Navy Marine Mammal Program
Authors: Mulsow Jason
Published: April 2023

Among the notoriously small sample sizes of marine mammals in cooperative behavioral research, there is an even smaller subset of subjects that can be considered “experts.” In essence, these are subjects that have “learned how to learn” in the contexts of novel experimental paradigms. One such subject is the bottlenose dolphin TRO at the US Navy Marine Mammal Program. The first scientific publication including TRO heralded his potential; aided by a phantom echo generator, he was likely the first marine mammal in history to echolocate while out of water. Subsequent behavioral experiments with TRO have examined numerous aspects of biosonar, including transmit beam characteristics and the use of click “packets” during long-range target detection. The patient nature of TRO has made him an ideal subject for electrophysiological studies, where he has diligently listened to exotic acoustic stimuli designed to examine auditory processing in the dolphin brainstem. The most significant scientific contributions from TRO are arguably from studies that have used auditory evoked potential methods during biosonar tasks. These data provide the temporal resolution necessary to examine hearing at the level of click production and echo reception and are a result of TRO’s dependable participation in studies combining multiple experimental techniques
Ronan and the legacy of Schusterman’s California sea lions
Authors: Jones Ryan A. , Cook Peter F. , Reichmuth Colleen
Published: April 2023

California sea lion Ronan was named in honor of Dr. Ron Schusterman, a pioneer in psychoacoustic studies of marine mammals. His early work with sea lions Sam, Rocky, Rio and others established rigorous methods for sensory assessment including those based on signal detection theory and the psychological principles underlying auditory learning and discrimination. Ronan is the most recent sea lion to join the research program in Santa Cruz, CA, adding to a long legacy of sensory and cognitive research. For more than a decade, Ronan has contributed to studies that increase understanding of marine mammal bioacoustics. These include marine and terrestrial audiograms that are often cited as representatives for the species, studies of ultrasonic hearing ability, and listening tasks performed in complex masking scenarios. Ronan is best known for her work on rhythmic entrainment, demonstrating auditory-motor synchronization and challenging theories as to the neural origin of this behavior. Ronan’s current psychoacoustics work is focused on understanding hearing at very low frequencies (<100 Hz) and the effects of parameters such as noise bandwidth and level on auditory masking.
The huaka‘i of Hawaiian monk seal Kekoa: Conservation through sound science
Authors: Parnell Kirby , Ruscher Brandi , Sills Jillian M. , Reichmuth Colleen
Published: April 2023

The Hawaiian monk seal (Neomonachus schauinslandi) is an endangered marine mammal and the subject of significant conservation concern. Limited bioacoustic information was available for this species until recently. The adult male Hawaiian monk seal Kekoa (KE18) was removed from the wild after repeated problematic interactions with conspecifics; he was then transferred temporarily to UC Santa Cruz, where he participated in studies to increase understanding of monk seal auditory biology. Compared to other seals, Kekoa’s behavioral hearing data suggest that monk seals have less sensitive hearing and a reduced functional frequency range of hearing in air and under water. A year-round characterization of his spontaneous underwater vocalizations revealed at least six low-frequency call types with a simultaneous peak in calling behavior and testosterone levels during the breeding season. Kekoa’s huaka‘i, or journey, has provided the first description of underwater communication for this protected species and contributed much-needed perspective about amphibious hearing abilities. Kekoa’s work has also inspired ongoing research with captive and wild individuals to confirm species-level traits in sound reception and production. These efforts have applications to studies of free-ranging monk seals through passive acoustic monitoring, development of automated call detectors, and the use of multi-sensor biologging devices.
From dynamic to passive elastography, what technique used?
Authors: Gennisson Jean-Luc
Published: April 2023

Elastography is a method that allows to quantify mechanical properties of biological tissues. In medical imaging, this last technique has been developed mainly in ultrasound (US) and in magnetic resonance imaging (MRI). Both imaging techniques have advantages and drawbacks depending on the organs and pathologies investigated. In this presentation we focused on two organs, where each technique has its advantage to investigate mechanical properties: brain and muscle. In brain, the preferred technique is MRI since US propagation is very complicated through the skull bone. Taking advantage of 3D acquisition, we investigated brain tumors with a new elastography approach: passive elastography. From the natural vibration, such as cardiac beating or respiration, we locally recover the natural shear wavelength that propagates giving access a stiffness mapping of the brain. Results are compared with US acquire during neurosurgery, showing a good accordance between both techniques. In muscles, US are used to recover not only stiffness but also others mechanical parameters such as viscoelastic anisotropy or shear non-linearity. Special US sequences were developed to quantify these two parameters in different physiological conditions that change in real-time. This presentation shows that depending on the investigated organ, physicists and physicians need to adapt the imaging strategy to better characterize tissues.
Ultrasound shear wave attenuation in nonalcoholic fatty liver disease: performance of the revisited frequency-shift method with pre-clinical and human datasets
Authors: Yazdani Ladan , Rafati Iman , Olivié Damien , Giard Jeanne-Marie , Sebastiani Giada , Nguyen Bich N. , Tang An , Cloutier Guy
Published: April 2023

Assessment of ultrasound shear wave attenuation (SWA) can increase the accuracy of liver steatosis grading. Recent developments allowed to propose the revisited frequency shift method for SWA imaging. This method was tested on force-fed ducks for foie gras production (n = 6), and a feasibility study on patients with non-alcoholic steatohepatitis (NASH n = 27 + 13 healthy volunteers) was conducted. Liver biopsy and magnetic resonance imaging proton density fat fraction (MRI-PDFF) were available as reference standards. For the human study, shear wave dispersion (SWD) was also computed. A subset of participants had repeated measurements (<1-month) to assess repeatability. The mean SWA (coefficient of variation within the attenuation map) for healthy duck livers were 0.77 (0.66), 1.18 (0.22), and 1.52 Np/m/Hz (0.14), and for fatty duck livers they were higher at 3.13 (0.55), 3.16 (0.24), and 4.84 Np/m/Hz (0.23). Receiver operating characteristic (ROC) curves using biopsy as reference were compared for steatosis grades >0 (>S0), >S1, and >S2. SWA was as good as MRI-PDFF, and both were better than SWD for steatosis grading (p < 0.05). The repeatability of SWA was very good (mean intraclass correlation coefficient of 0.97). In summary, SWA seems promising to become an ultrasound reference standard for steatosis grading in NASH.
Parametric evaluation of Kelvin-Voigt dispersion curve fitting
Authors: Vasconcelos Luiz , Kijanka Piotr , Urban Matthew W.
Published: April 2023

Ultrasound shear wave elastography (SWE) is a useful technique for non-invasive tissue assessment. For effective quantitative analysis the employment of physical models is necessary for rheological parameter estimation, such as the Kelvin-Voigt (KV) model. From SWE data, the frequency response can be calculated, and the shear wave velocity dispersion can be fit, yielding the shear elasticity and shear viscosity, μ1 and μ2, respectively. In this study, a parametric evaluation is performed using staggered-grid finite-difference simulations of materials with μ1 = 1–25 kPa (increment: 1 kPa) and μ2 = 0–10 Pa s (increment: 0.5 Pa s), with an acoustic radiation force push of f-number equal to 2. The novel Stockwell transform combined with a slant frequency-wavenumber analysis (GST-SFK) was compared with the two-dimensional Fourier transform for dispersion curve estimation over a variety of frequency ranges. Regardless of dispersion curve estimation technique, the accuracy of estimating μ1 is confounded for μ2 values above 5 Pa s. It was found that KV fitting benefits from wider frequency ranges (up to 1kHz), with lower μ1 and μ2 estimation errors. The GST-SFK was the best dispersion curve calculation technique, yet the KV fitting process was found to be unreliable for parameter estimation in highly viscous media.
Elastography using torsional wave motion in transverse isotropic material
Authors: Luna Aime , Salehabadi Melika , Klatt Dieter , Royston Thomas
Published: April 2023

An experimental configuration for driving and measuring torsional wave motion is designed, fabricated and experimentally tested using magnetic resonance elastography (MRE) in both a ultra-high field preclinical MRI system and in a cryogen-free low-field tabletop MRI system. Cylindrically-shaped isotropic and transversely isotropic phantoms, as well as the excised cat soleus muscle are statically stretched along their main axis to specific prestrain levels while simultaneously conducting MRE measurements with torsional waves. In the case of the excised cat soleus, diffusion tensor imaging is also performed to enable a co-registered mapping of fiber structure. The potential advantage of torsional wave excitation to drive shear wave motion over a large volume with uniform amplitude, and hence SNR, is tested by comparison to excitation of shear waves using other methods.
Theoretical and experimental investigation of the vaporisation of superheated perfluorocarbon droplets
Authors: Bau Luca , Wu Qiang , Ovenden Nicholas , Stride Eleanor P.
Published: April 2023

Acoustically activatable “nano”droplets consisting of superheated liquid perfluorocarbons have been investigated for both imaging and therapeutic applications. They offer longer circulation half-lives, higher surface area to volume ratio and the ability to perfuse the microvasculature more easily than gas-filled microbubbles. Optimising droplet formulations to avoid spontaneous vaporisation whilst keeping the peak negative pressure required for acoustic activation within the clinically safe range has proved challenging. The aim of this study was to derive a theoretical model to predict the probablity of droplet vaporisation under different conditions, the resulting bubble dynamics and radiated pressure; and compare the results with observations made by optical microscopy including high speed video. It was found that spontaneous vaporisation of perfluoropropane droplets occurred readily in serum at 37 °C in the absence of ultrasound excitation. Higher molecular weight perflurocarbons required acoustic activation and experimentally measured rates were higher than those predicted by modelling of homogeneous nucelation alone. The results suggest that droplet aggregation and heterogeneous nucleation play important roles in droplet vaporisation and should be accounted for in selecting appropriate ultrasound exposure conditions. The prevalence of spontaneous vaporisation may also have important safety implications for clinical applications of low boiling point perfluorocarbon droplets.
Monitoring cavitation dynamics evolution in tissue mimicking hydrogels for repeated exposures via acoustic cavitation emissions
Authors: Haskell Scott , Sukovich Jonathan R. , Xu Zhen
Published: April 2023

Acoustic cavitation emission (ACE)/shockwave signals generated by cavitation during histotripsy have been demonstrated to undergo characteristic changes correlated with the level of damage generated in select target media following repeated cavitation exposures, and may allow assessment of therapy-induced tissue damage during histotripsy. Here we investigate the impacts of nucleation medium on the evolutions of cavitation dynamics and ACE signals during repeated cavitation exposures. Repeated cavitation is generated in agarose, gelatin, and polyacrylamide hydrogels using a 700-kHz histotripsy array. High-speed imaging, broadband hydrophones, and histotripsy array elements are used to measure ACE signals and bubble dynamics. Bubble lifespans and collapse shockwave amplitudes were observed to be equivalent in optical and acoustic measurements. However, the evolutions of these properties, as well as bubble maximum radii, varied significantly across materials. Maximum radii initially increased and then decreased in agarose, but remained constant in gelatin and polyacrylamide. Lifespans increased monotonically in agarose and gelatin, but decreased in polyacrylamide. Collapse shockwave amplitudes evolved differently in all materials. The observed evolutions of the maximum radii, lifespans, and collapse shockwave amplitudes between media suggest that these features are dependent on the structure and stiffness of the nucleation medium and must be further investigated in tissues.
Numerical modeling of knocking combustion in spark ignition engines
Authors: Ameen Muhsin , Pal Pinaki
Published: April 2023

At present, around 85% of the 1.1 billion passenger cars in the world are powered by gasoline spark ignition (SI) engines. Engine downsizing coupled with boosted operation and transition to sustainable fuels is considered an attractive strategy to enhance power density and reduce fuel consumption of SI engines. However, these operating conditions result in severe thermodynamic conditions, thereby promoting the likelihood of abnormal combustion phenomena such as knock. The severity of knock can vary significantly, and the efficiency of engines at high loads is limited in practice by heavy knocking phenomena. Since, a thorough analysis of such recurrent but non-cyclic phenomena via experiments alone becomes highly cumbersome, in the present work, a multi-cycle large-eddy simulation study was performed to quantitatively predict cyclic variability in the combustion process and cyclic knock intensity variability in a direct injection spark-ignition engine. For both the mild knock and heavy knock conditions, the numerical results were validated against experimental measurements. Based on the simulation results, a correlation analysis was performed considering combustion phasing, peak cylinder pressure and maximum amplitude of pressure oscillation. Furthermore, a detailed three-dimensional spatial analysis illustrated the evolution of auto-ignition kernel development and propagation of pressure waves during knocking combustion.
Modeling the performance of a family of phononic pseudo-crystal interposers
Authors: Swift S. Hales , Smith Chandler , Kellogg Rick A. , El-Kady Ihab F.
Published: April 2023

Recent technical efforts at Sandia National Laboratories have uncovered a need for high-frequency isolation in solid media across a range of ultrasonic frequencies; these needs include the requirement to suppress crosstalk between piezo-mechanical data and power channels situated on the same substrate. Broadband isolation larger than is possible with comparable phononic crystal designs is provided using a recently-developed phononic pseudo-crystal isolator concept. Insertion loss results from 2-D finite element simulations in COMSOL and 3-D simulations in Sierra-SD, Sandia’s HPC compatible structural dynamics simulation platform, are used to characterize the performance of characteristic examples of this family of phononic isolators. Sierra-SD uses massively parallel computing and high-order polynomial finite elements (P-elements) to mitigate the computational cost required to simulate coupled electrical-mechanical 3-D ultrasonic wave propagation. [SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525.]