bluuebunny/crossref_metadata_2025 huggingface dataset:
Microvascular no reflow in acute MI—Mechanistic studies of sonoreperfusion
Authors: Pacella John J.
Published: April 2023

Congestive heart failure (CHF) following acute myocardial infarction (AMI) is on the rise. Microvascular obstruction (MVO) is the single most important contributor to post-AMI CHF; it occurs in up to 80% of patients with AMI and is associated with worse outcomes. To address this unmet need, we have been developing ultrasound targeted microbubble cavitation (UTMC) to achieve “sonoreperfusion” (SRP) for MVO. During SRP, US is applied to intravenously administered MBs as they transit the coronary microcirculation, which causes MBs to oscillate and generate shear stress. We have previously shown that SRP therapy restores perfusion during MVO through direct mechanical “chiseling” effects of MBs on microthrombi. However, MVO is more than just physical obstruction from microemboli; it is characterized by a milieu of inflammation and oxidative stress, a state of imbalance between the formation of damaging reactive oxygen species (ROS) and antioxidant defenses. One such defense is nitric oxide (NO), which has multi-level therapeutic potential for MVO. We have demonstrated that UTMC releases NO from endothelial cells through mechanotransduction, and that NO is a major contributor to the efficacy of SRP. We are now actively pursuing strategies to optimize SRP, not only through mechanical mechanisms but also by addressing oxidative stress.
Technological considerations for delivering focused ultrasound exposures to the spinal cord
Authors: O'Reilly Meaghan
Published: April 2023

Focused ultrasound opening of the blood-brain barrier (BBB) has reached clinical investigations and seems poised to revolutionize the treatment of brain disorders. Far less attention has been paid to the spinal cord and functionally equivalent blood-spinal cord barrier (BSCB). Small and large animal studies demonstrate that ultrasound and microbubbles can be used to modulate the BSCB in a similar manner to the BBB. However, the complex bony geometry of the vertebral column poses a challenge to the non-invasive delivery of therapeutic ultrasound exposures to the spinal canal. This talk will review work developing spine-specific ultrasound pulse trains and identifying optimal apertures for maximizing sound transmission through the vertebral arch.
Sonobiopsy for expanding the application of therapeutic ultrasound in the diagnosis of brain diseases
Authors: Chen Hong
Published: April 2023

Focused ultrasound (FUS) was introduced for brain applications in the 1940s and has been employed as a therapeutic tool since then. FUS-mediated thermal ablation treatment of essential tremors was approved by the U.S. Food and Drug Administration (FDA) in 2016. FUS combined with microbubbles for inducing BBB disruption to deliver neurotherapeutic drugs to the brain is currently in early-phase clinical trials. We proposed to use FUS as a brain disease molecular diagnostic tool. Sonobiopsy uses FUS to release brain disease-specificbiomarkers (e.g., DNA, RNA, and proteins) from the brain to the blood for the diagnosis of brain diseases by blood tests. Sonobiopsy does not involve any neurotherapeutic drugs, which may accelerate FDA approval of the FUS technique. Sonobiopsy opens new research opportunities that have the potential to substantially improve the diagnosis of a broad spectrum of brain tumors. This talk will present recent progress in the development of sonobiopsy technique for the diagnosis of brain cancer and Alzheimer’s disease. This talk also will present recent achievements in the clinical translation of sonobiopsy.
Therapeutic ultrasound to market
Authors: Morrison Kyle P. , Chavez Francisco
Published: April 2023

Therapeutic ultrasound is proving to be viable in the clinic and is producing a high level of commercial activity in Therapeutic Ultrasound Systems globally across a wide variety of clinical indications. Recently there has been an increased level of commercial interest in systems delivering lower intensity ultrasound. Some examples of clinical indications include modulating nerves, sonodynamic therapy, or combining ultrasound with drugs to lower the threshold of required intensities. Regardless of the acoustic intensity required, new product inception will adopt an effective bio-acoustic result to match a clinical indication, creating a gap in product development. Sonic Concepts provides transmit ultrasound development services to fill this gap through a phased development program, accelerating first-in-man and time to market. Sonic Concepts has co-developed 30 + clinical systems, servicing customers with more than 100 years of accumulated experience, creative design techniques, and a spectrum of products and intellectual property to leverage. Examples of co-developed clinical systems will be presented, detailing the process from initial concept to first-in-man while using pre-clinical systems, HIFUPlex™ and NeuroFUS® to fast-track development.
Feasibility of MRI-guided focused ultrasound-mediated intranasal delivery in a large animal model
Authors: Fadera Siaka , Xu Lu , Chien Chih-Yen , Yue Yimei , Ye Dezhuang , Chukwu Chinwendu , Chen Hong
Published: April 2023

Intranasal delivery provides non-invasive delivery of drugs from the nose to the brain bypassing the blood-brain barrier (BBB). We previously reported the focused ultrasound (FUS)-mediated intranasal delivery (FUSIN) of various agents in mice using FUS. However, no study has investigated the feasibility of FUSIN in large animals. The objective of this study was to investigate the feasibility of MR-guided FUS-mediated intranasal delivery in a large animal model. Pigs were used as the large animal model due to their clinical relevance to humans. Fluorescence-labeled albumin was mixed with an MRI contrast agent and administrated intranasally to the pig using a catheter. Followed by intravenous injection of microbubbles, FUS sonication was performed at two brain regions, the cortex and brainstem. T1-weighted MR images showed enhancement of MRI contrast agent at the olfactory region of the pig nose. Fluorescence imaging displayed enhanced fluorescence intensity at the FUS-targeted brain regions. These findings suggest that MR-guided FUS can achieve noninvasive and localized delivery of intranasally administered agents to the brain in large animals.
MRI-guided focused ultrasound drug delivery to DMG tumors in a mouse model
Authors: Martinez Payton , Green Adam , Borden Mark
Published: April 2023

Diffuse midline glioma (DMG) is the most common and unfortunately the most deadly brainstem tumor in childern. Current clincal treatment methods only involve palliative radiotherapy that does not significantly improve survival beyond its poor mean survival of 9 months. These tumors remain difficult to treat with chemotherapy as they maintain an intact blood brain barrier (BBB). Focused ultrasound (FUS) and microbubbles (MBs) has been shown to disrupt the BBB, allowing chemotherapeutics to enter the perenchyma. Panobinostat is one of the chemotherapeutics that has difficulty crossing the BBB, although it has promising effects in vitro. In this study, we hypothesized that MB + FUS could disrupt the BBB, allowing a higher concentration of Panobinostat to enter the tumor region and provide a therapeutic effect. Our results demonstrate that MB + FUS can successfully deliver Panobinostat to the pons with DMG tumors over 3-fold, while only slightly increasing the concentration of the forebrain. Passive cavitation detection during treatments showed harmonic cavitation throughout the 3-minute treatment, while not having any significant broadband cavitation. The combination of both Panobinostat and MB + FUS showed major decreases in tumor growth by ∼71% by the end of the treatment weeks when compared to Panobinostat alone. A significant survival benefit was also demonstrated.
Characterization of infrasonic wind noise using the Discrete Orthonormal Stockwell Transform
Authors: Frazier Garth
Published: April 2023

The Discrete Orthonormal Stockwell Transform (DOST) (Stockwell, 2007) projects a finite-length, periodically sampled signal onto a set of orthonormal basis vectors that are localized in time and scale such that all basis functions at each scale are represented by a finite number of Discrete Fourier Transform (DFT) basis functions. It is based on the Stockwell Transform (Stockwell et al., 1996), sometimes referred to as the S-transform, which is applicable to continuously defined waveforms. Furthermore, the DFT basis functions corresponding to each DOST scale are non-overlapping. The shorter DOST scales correspond to higher-frequency DFT basis functions and greater bandwidths than the longer DOST scales. Thus, the DOST is a type of time-frequency transform and is suitable for non-stationary time-series analysis. Additionally, the DOST of an N-point record can be calculated efficiently in order N log N operations (Wang and Orchard, 2009). Several applications of the S-transform and the DOST have been documented including beamforming with array data (Collar and Frazier, 2022; Frazier, 2022). In this presentation, the DOST used is to examine the statistics of data measured with infrasound sensors as a function of the DOST scales, adaptively characterize the amplitude distributions of the DOST coefficients at each scale and perform near-optimal detection of transient signals. Results corresponding to infrasound data recorded under various conditions are presented.
A new sixth-order Eigenmike® spherical microphone array for spatial sound field recording
Authors: Elko Gary W. , Meyer Jens , Backer Steven
Published: April 2023

A new spherical microphone array capable of up to 6-th order spatial sound field recording is described. Spherical microphone array beamforming is normally accomplished by judicially combining multiple acoustic pressure microphones appropriately mounted on the surface of a rigid sphere to form a set of orthonormal spherical harmonic modal beams or “Eigenbeams” (also referred to as Higher-Order-Ambisonics). Eigenbeamformer processing exploits the diffraction and scattering of the incident acoustic waves onto the rigid sphere. General beamformers are then created by properly combining the orthonormal Eigenbeams to form and steer a desired set of beampatterns up to the decomposition order limit. One advantage of using the modal decomposition approach to beamforming is that it is computationally compact, and results in an elegant scalable beamformer architecture. Steering beams formed by the spherical array is accomplished by a computationally simple matrix multiply. Another benefit is that beampatterns formed using spherical array processing maintain their design spatial responses independent of the steering direction. Beampatterns can also be frequency independent. In this talk, we will describe a new 64-element spherical microphone array and associated software capable of up to 6-th order performance, as well as present some real-world measurements.
The design of an optomechanical microphone using a photonic waveguide interferometer
Authors: Niu Xiaoyu , Meng Yuqi , Vatankhah Ehsan , Hall Neal A.
Published: April 2023

Most commercial microphones rely on capacitive or piezoelectric readout of a vibrating diaphragm. Optical methods have also been used to read the motion of a vibrating microphone diaphragm. Most optical microphone demonstrations to date use free-space optics. We present the design of an optical interferometric microphone that uses a photonic waveguide embedded within the diaphragm. The deflection of the moving diaphragm causes a strain field within the diaphragm, and this strain in turn changes the optical path length of the waveguide. Light traversing the sensing arm of the interferometer combines with light traversing an on-chip reference arm to yield an output light power that depends on the instantaneous displacement of the diaphragm. The output of the combined beams is coupled from the chip to a photodetector to complete the interferometer. An advantage of such transduction method is the absence of a microphone backplate and its associated thermal-mechanical noise. Electrical noise associated with high input-impedance amplification, as required for small capacitive and piezoelectric sensors, is also circumvented. This embodiment does, however, introduce several implementation challenges including the routing of light onto and off the microphone diaphragm.
Using the mechanical waves concept survey in a non-majors acoustics class
Authors: Riegel Kimberly A.
Published: April 2023

The Mechanical Waves Concept Survey (MWCS) is a concept inventory designed to identify common misconceptions specifically related to Waves and Optics. It is a 22 question multiple choice assessment designed to be given pre and post instruction. The development of this inventory involved many revisions and administering the test to hundreds of students ranging from high school to university students in several different countries including Mexico, Thailand, and Australia. The use and effectiveness of the MWCS in other settings such as America, community colleges and non-majors courses have not been thoroughly examined. This presentation will outline results for an American community college specifically for students who are not intending to be STEM majors. Several semesters of assessment data will be presented. Due to the change in instruction modality during COVID, a comparison between delivery methods, in person and online was examined. Future work regarding improvements to the concept inventory will be discussed.
Development of a waves and vibration concept inventory: Challenges and applications
Authors: Piacsek Andrew A.
Published: April 2023

A useful tool for measuring learning gains and for assessing the effectiveness of instruction in the physical sciences is the “concept inventory.” This is a set of questions administered at the beginning of a course, or prior to a unit of instruction, as well as at the conclusion. Students may told their scores, but are not provided with the answers. An early example is the Force Concept Inventory (FCI), published in 1992, which has been widely adopted for use in introductory physics courses and has served as the model for concept inventories. This presentation describes the ongoing development of an inventory designed to test conceptual understanding of basic principles of vibration and wave propagation that are typically covered in a first-year physics course or introductory or intermediate courses on acoustics-related topics. The current version builds on previous work by the author to develop a more focused inventory for an introductory course in musical acoustics (https://asa.scitation.org/doi/10.1121/1.5067886). Results from the trial use of this inventory in multiple courses at Central Washington University will be discussed.
Wind farm acoustics course for engineering students
Authors: Lai Heather L. , Balant Anne C.
Published: April 2023

The Accreditation Board for Engineering and Technology (ABET) has two learning outcomes for all engineering students that relate to “public health, safety, and welfare” and the need to consider “the impact of engineering solutions in global, economic, environmental, and societal contexts.” We describe the development of a one-credit hybrid course on wind energy acoustics that meets these learning outcomes. This course was one of five one-credit modular courses on different aspects of wind energy developed via a SUNY-funded initiative. Topics included human and environmental impacts of wind farm noise, sound perception, noise regulations, wind farm noise generation and propagation, and noise control. Students gained the acoustics background needed to understand the necessary technological aspects of wind farm noise. They used simple models to predict community noise levels and assess noise control strategies and then completed a case study project in which they proposed and debated strategies for reducing the negative impacts of a controversial wind farm. Upon completion of the course, the students expressed that they had not previously considered the possible impacts of wind farm noise. They seemed to have grown in their ability to think holistically about the potential societal and environmental impacts of wind farm noise.
Response variations in psychoacoustic tests focused on the assessment of tonal office noise
Authors: Song Guochenhao , Davies Patricia , Liu Yangfan
Published: April 2023

Tonal noise from rotating machinery is known to be a problem in buildings. To guide the design of a comfortable office environment, a proper understanding of people’s annoyance due to exposure to tonal office noise is valuable. Earlier, authors have proposed and verified two annoyance prediction models based on the psychoacoustic subjective tests conducted in an office mock-up, and further developed a software to implement the metric models. In the present work, the focus is shifted to some unexpected response variations observed while analyzing the responses from subjective tests: (1) the learning pattern that occurs at the beginning of the test; (2) the significant differences in the averaged annoyance ratings with respect to the gender and the Noise-Sensitivity-Questionnaire (NoiSeQ) score; (3) the acclimation to sounds: i.e., the annoyance ratings for the 2-min sounds were lower than the ratings for the corresponding 5-s sounds; and (4) the inconsistencies in ratings: i.e., subjects tend to use the annoyance scale differently in different parts of the test and to rate sounds relative to the background level in the room. In the end, several approaches to deal with these response variations and a few recommendations on the psychoacoustic test design are summarized.
Evaluation of tone annoyance metrics on reverberation room measurements of HVAC equipment
Authors: Bauch Paul F. , Balaguru Rajavel
Published: April 2023

Reverberation rooms are a primary tool for HVAC equipment manufacturers to calculate equipment sound power levels, which lead directly to equipment sound ratings. While sound quality has been included in standards, namely, the withdrawn AHRI 1140, the adoption and value of those standards has been minimal leaving specifiers to construct their own tone quality metrics. This paper will evaluate the application of common sound quality metrics, specifically tonal metrics, to reverberation room measurements. Room response is a critical factor in measuring tone prominence, especially at lower frequencies where adjacent frequency tones can vary by 6dB or more. Metrics evaluated include TTNR, Prominence, Tonality and a new metric developed in ASHRAE 1707-TRP.
Ambient noise definitions in municipal codes and the application of acoustical engineering
Authors: Roberts Jordan L. , Dong Wayland , Lo Verde John
Published: April 2023

The duration of a noise measurement period that is required to establish an ambient or background noise level can vary drastically, from minutes to years. The descriptor of ambient noise levels can also vary whether it is a time-average sound level (Leq), or an x-percentile-exceeded sound level (L50, L90) for a specified duration. None of the above methods are necessarily right or wrong, however some may be more or less appropriate depending on the sources of sounds that are sought to be regulated, the context of potential human impact, and the goals of the municipality. This session will present examples of ambient noise measurement procedures as informed by municipal code language, discuss the noise sources that are likely to exceed the respective ambient, and determine if the limits are appropriate, can be left to interpretation, or would require additional definition to properly represent conditions.
Conversion of tones to soothing noise
Authors: Han Xue , Hu Ying , Zhang Yumin , Huang Lixi
Published: April 2023

When pure-tone sound signal of frequency fs interacts with a boundary whose acoustic property varies at a frequency of fm, part of the incident sound energy is scattered to the sum and difference frequencies, fs ± n fm, where n is any integer but n = 1 dominates. When the modulation frequency fm has a bandwidth, spanning from fm1 to fm2, the resulting scattered sound carries the same bandwidth of fm2-fm1. In this manner, pure tone is partly converted to broadband noise and will be less annoying to human ears. This talk first introduces the initial experimental evidence of such frequency scattering using a realistic design (see reference paper with doi:10.1038/ s42005-021-00721-1). Then the latest results of numerical study on the maximization of the energy scattering is presented. An attempt is also made to examine the question of what room mode or eigen frequencies will be when part of the room boundaries has a time-dependent wall properties. Note that the time-varying wall remains passive in the sense that the property variation is independent of the incident sound and there is no energy input required.
Quartz enhanced photoacoustic spectroscopy gas sensing exploiting beat frequency approach
Authors: Menduni Giansergio , Li Biao , Zifarelli Andrea , Giglio Marilena , Sampaolo Angelo , Patimisco Pietro , Wei Tingting , Wu Hongpeng , Dong Lei , Spagnolo Vincenzo
Published: April 2023

Quartz-enhanced photoacoustic spectroscopy (QEPAS) is a highly sensitive optical technique, suitable for real-time and in situ trace gas detection. In QEPAS, Quartz tuning forks (QTF) are employed as piezoelectric transducers of sound waves induced by gas non-radiative energy relaxation as consequence of infrared modulated light absorption. The generated electric signal depends on the gas concentration. An accurate and reliable QEPAS measurement requires the QTF characterization, in terms of resonance frequency and quality factor. Furthermore, tens of seconds are required to complete the tuning range scan of the laser employed to detect the selected gas. Beat frequency QEPAS (BF-QEPAS) is an alternative approach to standard QEPAS. In BF-QEPAS, a fast scan of the laser tuning range is employed to generate an acoustic pulse. Gas concentration, QTF resonance frequency, and quality factor can be measured acquiring and analyzing the transient response of the QTF to the acoustic pulse. In this work, a custom T-shaped QTF was employed to detect nitrogen monoxide (NO), targeting its absorption feature at 1900.07 cm−1 with an interband cascade laser. A minimum detection limit as low as 166 ppb of NO, and a highly accurate measurement of the QTF resonance frequency and quality factor were demonstrated using BF-QEPAS.
Broad phonetic feature classifier for real-time hearing aid processing
Authors: Kamath Prasad Madhava , Hunt Martin , Rao Bhaskar D , Garudadri Harinath
Published: April 2023

Current Hearing Aid (HA) devices compensate for hearing loss by amplifying sounds based on instantaneous energy estimates in specific frequency bands. The dynamics of speech are incorporated using attack and release times—a crude approximation of the rich temporal dynamics in natural speech. Recent advances in silicon enables one to consider more complex sound processing approaches with minimal impact on the HA battery life. We envisage a broad phonetic feature classifier, followed by amplification strategies optimized for specific temporal dynamics across each segment of natural speech. In this work we present a broad phonetic classifier for ‘vocalic’, ‘non-vocalic’ and ‘mixed’ speech segments. The classifier is based on (i) Interpretable models- unsupervised learning methods such as Gaussian Mixture Models followed by supervised learning based Radial Basis Function networks; and (ii) Deep Neural Networks with supervised learning. The frontend feature extractor consists of MFCC, delta MFCC features, spectral flatness measure and segmental energy. The training and test sets are generated using speech files and the corresponding phone labels from the TIMIT dataset. We present our findings with respect to the classifier's performance and deployability for real time HA processing.
Acoustic feedback control in hearing aids with frequency warping
Authors: Sokolova Alice , Rallapalli Varsha H. , Yellamsetty Anusha , Hunt Martin , Aksanli Baris , Harris Fredric , Garudadri Harinath
Published: April 2023

Acoustic Feedback Control continues to be a challenging problem due to the emerging form factors in advanced hearing aids and hearables, especially for severe and profound losses. In order to mitigate the effects of feedback in hearing aids, we present a novel use of frequency warping called “Freping,” for manipulating signals in the frequency domain. Freping is a non-linear transformation which breaks the similarity between the input and acoustic feedback signals of a hearing aid to prevent feedback. In this work, we implemented Freping in realtime for feedback management, as well as novel techniques to preserve the naturalness of sound. Our prior work has shown that Freping improves Added Stable Gain (ASG) in the presence of feedback while maintaining the same Hearing Aid Speech Quality Index (HASQI). We present new results for feedback management with Freping by performing “on-ear” measurements on an acoustic KEMAR manikin using standard hearing aid verification systems. We conducted feedback tests to measure the ASG with various configurations of Freping for various hearing loss levels using the NAL-NL2 prescriptions on a realtime open-source speech processing system for hearing aids. We also compare Freping feedback performance with that of commercial hearing aids.
Cross-species characterization of joint otoacoustic emission profiles in sensorineural hearing loss
Authors: Hauser Samantha , Heinz Michael G. , Bharadwaj Hari
Published: April 2023

Current clinical assessment of otoacoustic emissions (OAEs) is typically limited to presence or absence of emissions to detect hearing loss, but recent work suggests advanced analyses and data collection methods have the potential to improve the diagnostic utility of OAEs. OAEs arise from two distinct mechanisms, nonlinear distortion and linear reflection, which are both sensitive to the health of outer hair cells but may reflect separate aspects of cochlear mechanical function. Joint distortion-reflection OAE profiles offer a non-invasive characterization of peripheral auditory physiology and dysfunction (Abdala and Kalluri, 2017). In this study, swept-tone distortion-product OAEs were separated into distortion and reflection components. Swept-tone stimulus-frequency OAEs, reflection-type emissions, were measured using a suppressor paradigm. Joint OAE profiles will be estimated for multiple pre-clinical chinchilla models of sensorineural hearing loss (SNHL) and in humans with either normal hearing or sensorineural hearing loss. In chinchillas, we expect SNHL models with distinct profiles of cochlear damage to yield separable joint OAE profiles. Findings in chinchillas will provide mechanistic insight into OAE profile clusters in humans. These data test the sensitivity of joint OAE profiles to specific cochlear dysfunctions and contribute to development of precision diagnostics for SNHL.
Reaching new levels of wave scattering via piezoelectric metamaterials and electro-momentum coupling
Authors: Lee Jeong-Ho , Zhang Zhizhou , Gu Grace X.
Published: April 2023

Piezoelectric materials are materials that can convert mechanical energy into electrical energy (and vice versa). In addition to the well-known electromechanical interaction between mechanical deformation and electric fields, a recent discovery revealed that the macroscopic linear momentum of piezoelectric materials is also coupled with the electric field. This means that their kinetic movement can be controlled by the electric field. This effect is termed electro-momentum (EM) coupling and provides a new design degree of freedom for piezoelectric devices with better properties and dynamic performance. In this talk, theoretical bounds of EM coupling in wave scattering will be discussed, which can provide valuable information on estimating the performance space of piezoelectric metamaterials for various applications such as acoustic sensing and energy harvesting. The results show that scattering performance from EM coupling can be of the same order of magnitude as that of the scatterer’s geometric features, such as shape and size, which are considered major factors for scattering performance. Furthermore, its capability of promising wave manipulation will be demonstrated, i.e., tunable scattering-cloaking piezoelectric devices via EM coupling. Moreover, how material properties and geometrical microstructures affect EM coupling will be investigated, which allows researchers to precisely control EM coupling in piezoelectric materials.
Roton- and maxon-like dispersion relations in elastic metamaterial
Authors: Zhang Peng , Chen Fei , Zhu Xuan , Wang Pai
Published: April 2023

Rotons and maxons are local minima and maxima in the frequency-wavenumber spectrum, respectively. They represent wave modes with a vanishing group velocity and a finite phase velocity. Recent advancement showed that roton dispersion relations are not restricted to low-temperature quantum systems but can also be engineered in 3D elastic metamaterials. Here, we report that zero-group-velocity (ZGV) wave modes, similar to rotons and maxons, can be found in elastic waveguide structures with resonators. In addition, we perform parametric study on the parameters of the resonator unit. By tuning the parameters, the roton and maxon may coalesce into a second-order critical point (undulation point or stationary inflection point), where the second derivative of frequency with respect to wavenumber vanishes. This introduces a new non-spreading localized wave mode. Not only is such wave mode non-propogating, but it is also non-diffusing. Inthis case, the highly localized vibration can support energy trapping andenhance the signal-to-noise ratio in wave-based structural health monitoring.
Modeling and characterizing the dynamic response of Octet-Truss lattice structures using elastic parameters determined from Resonant Ultrasound Spectroscopy
Authors: Fisher Karl A. , Wang Jenny , Tran Brian
Published: April 2023

Modeling and characterization of additively manufactured materials and structures is a critical stage in the design process. This presentation will present an approach using Resonant Ultrasound Spectroscopy to determine the elastic tensor of an additively manufactured Octet Truss lattice structure. The lattice structures are fabricated from an alloy of Titanium using a laser powder bed fusion process. Material characterization begins by applying resonance techniques on simple regular parallelepiped shapes. Solid and lattice samples are measured to obtain estimates for the elastic properties of the bulk material and the effective elastic properties of the lattice structure. The measured elastic properties are then incorporated into structural models representing continuum approximations of several test parts. Comparisons between the continuum models and the experimental measurements indicate agreement over a wide frequency range within a long wavelength approximation defined for the lattice. The measurements also suggest that there is additional physics and geometrical effects accounted for in the RUS continuum approximations of the lattice that are not completely captured by the full finite model utilizing only base material properties.
Ultra-broadband acoustic metasurface for speaker directivity control
Authors: Li Junfei , Peng Xiuyuan , Hernandez Gregory , Cummer Steven
Published: April 2023

Acoustic metasurfaces have shown remarkable capabilities for shaping acoustic wavefronts. However, most thin metamaterials can only work well for a narrow range of acoustic frequencies. This limitation has thus far dramatically limited their potential for human-based audio and acoustic applications. Here we present a generic acoustic metasurface design approach to reshape acoustic wavefronts in a broad bandwidth. As a demonstration, we designed two acoustic lenses. The first acoustic lens converts a 4-in. speaker into an omnidirectional source, covering a frequency range from 1 to 10kHz. The second acoustic lens delivers super-directionality for a 1-in. speaker from 1 to 20 kHz. Experimental measurements showed great agreement with the simulations. Our design approach enables the design of ultra-broadband metasurfaces useful for audio applications.
Clear speech and phonological typology: A case study of Tashlhiyt Berber
Authors: Zellou Georgia , Lahrouchi Mohamed , Bensoukas Karim
Published: April 2023

Clear speech is a type of listener-oriented, intelligibility-enhancing mode of speaking. It has been shown to enhance the perceptibility of many different types of phonological contrasts, cross-linguistically. An open question is whether all phonological contrasts are enhanced to an equivalent extent in clear speech. In the current study, we ask whether rarer phonological patterns receive less of a clear speech intelligibility boost, relative to more common phoneme contrasts. Tashlhiyt Berber is an Afroasiatic language spoken in Morocco. Tashlhiyt has been well studied for having typologically uncommon phonotactic properties. This study examines the effect of clear speech on the discrimination of rarer lexical contrasts in Tashlhiyt Berber. We predict that the more typologically uncommon contrasts (e.g., word pairs containing complex and geminate initial onsets) will have a smaller increase in perceptibility from casual to clear speech than more common contrasts (e.g., singleton contrasts). Furthermore, native and naive listeners’ (here, American English speakers) discrimination of these contrasts across speech styles is also compared. Cross-language perception of clear speech provides a window to understanding the phonetic bases for cross-linguistic typological patterns.
Influence of noise on perception of different types of dysarthric speech
Authors: Wang Emily Q. , Shafiro Valeriy
Published: April 2023

Disturbances in the central nervous system may lead to changes in the speech muscle system, which impact muscle strength, tone, and coordination as well as movement speed, resulting in different types of dysarthria, each impacting respiration, phonation, articulation, resonance, and prosody differentially. Bilateral upper motor neuron damage leads to spastic dysarthria, cerebellar damage ataxic dysarthria, and damage to basal ganglia hypokinetic dysarthria. In estimating the severity of speech impairment, and measuring speech intelligibility, both reading and spontaneous speech samples are routinely used by speech-language pathologists. However, noise levels in acute and rehabilitation hospitals often exceed the World Health Organization guidelines (Busch-Vishniac et al., 2005) which may impact the clinical outcomes. In this study, 100 graduate student clinicians in Speech-Language Pathology measured speech intelligibility and estimated the severity of speech impairment of speech samples produced by three types of dysarthric speakers: spastic, ataxic, and hypokinetic, in two different noise conditions (quiet, and hospital noise). The differential impact of noise on different types of dysarthria is examined, and its implication on clinical outcomes is discussed.
Medically related speech: Impacts of age, familiarity, and noise on word recognition
Authors: Puckett Brian J. , Ryherd Erica E. , Bent Tessa , Baese-Berk Melissa M. , Manley Natalie
Published: April 2023

Verbal communication between patients and healthcare providers is an important piece of successful healthcare delivery. Less familiar medical terminology coupled with noisy hospital environments can lead to speech intelligibility challenges between healthcare providers and patients. Prior results showed lower word recognition accuracy for lower familiarity and frequency words and in the presence of noise in younger adults (Bent et al., 2022). The current study expands on the previous work with the inclusion of older adults and an additional noise masking condition. Online listening tests were conducted to study the impacts of word familiarity and background noise on speech perception in younger (age 18–35) and older adults (age 60–85). Participants were presented with a corpus of 160 medically related sentences with varying word familiarity and frequency characteristics, and word recognition accuracy was recorded. Sentences were presented in quiet, hospital noise, speech-shaped noise, and speech-shaped noise modulated by the hospital noise envelope, a novel condition from previous work. Results highlight a comparison of speech recognition performance between the two age groups. Effects of sentence familiarity/frequency rating and type of noise masker on speech intelligibility are discussed. [Work supported by the James S. McDonnell Foundation https://doi.org/10.37717/2021-3028.]
High spectral covariation between frequency channels contributes to clear speech intelligibility
Authors: Llanos Fernando , Meemann Kirsten , Smiljanic Rajka , Chandrasekaran Bharath
Published: April 2023

Speech signals are acoustically redundant, which could explain why sentence intelligibility is fairly robust even when sentences are acoustically degraded. We investigated the contributions to sentence intelligibility of clear speech redundancy encoded as patterns of spectrotemporal covariation between frequency channels. Participants (N = 16) transcribed 120 clear-speech English sentences acoustically degraded to 5, 8, or 15 frequency bands derived from an ERB-scaled filter bank. Before the acoustic degradation, each sentence was expressed as a linear combination of principal component eigenvectors representing different patterns of covariation between channels. Half of the sentences preserved the channels providing larger score magnitudes for the eigenvector accounting for more spectral covariance (high-covariance condition). These channels represented the spectral covariation patterns that were more dominant in each sentence. The other half of the sentences preserved the bands conveying larger score magnitudes for the eigenvector accounting forless spectral covariance (low-covariance condition). These bands represented the spectral covariation patterns that were less dominant. Participants yielded significantly better transcription accuracy in the high-covariance condition (mixed-effects, ps < 0.0021). Critically, accuracy in this condition was higher than 56% on average for as few as 5 bands. These findings indicate that clear speech intelligibility is supported by patterns of spectral covariation between frequency bands.
The perception of acoustically distorted speech produced with face masks in multilingual multi-talker environments
Authors: Chiu Faith , Bartoseviciute Laura , Lee Albert , Yao Yujia
Published: April 2023

This paper examines the perception of speech produced with face masks in multilingual multi-talker environments. Three groups of participants varying in language background listened to and reported English target sentences produced with or without a face mask in the presence of a competing English or Lithuanian talker. Listeners were monolingual native speakers of English, second language (L2) English speakers with Lithuanian as first language (L1), and L2 English speakers with L1 Mandarin Chinese. In addition, Lithuanian speakers also completed the same experiment but with Lithuanian targets. Results indicate that participants were more accurate with perceiving target sentences in their L1. Targets produced with a face mask were less accurately perceived across all groups regardless of listening in L1 or L2. In general, a competing talker in a language which matches the target (English distractor on English target) had a more detrimental effect on perception accuracy than a mismatched one (Lithuanian distractor on English target). Exceptionally, only when Lithuanian participants—with both English and Lithuanian knowledge – listened in their L1 was there no added challenge from matching distractor and target language. We conclude that acoustic distortions from face masks present an across-the-board difficulty while linguistic knowledge can reduce distraction from competing talkers.
Misperception in Northern Vietnamese Tones due to the Lombard effect
Authors: Le Giang , Tang Yan
Published: April 2023

Studies examining Lombard speech have found that intelligibility often increases due to acoustic changes such as elevated intensity, increased F0 and F0 range, and elongated sonorous segments. By previously studying the production of the eight lexical tones in Northern Vietnamese in noise, we have also observed that all tones experienced differing degrees of the Lombard effect. For instance, tone B2 (mid-falling with creakiness) showed resistance to increased glottal regularity, while tone C2 (mid-rising with creakiness) exhibited a greater convergence towards regular phonation. The current study conducted a perception experiment to investigate to what extent those acoustic adaptations due to hyper-articulation impact listeners' perception of tonal identity. Native Vietnamese listeners identified the tones produced in quiet or in noise of 78 or 90 dB SPL by a male and a female speaker. The results show that the creaky tones B2 and C2 had the lowest identification accuracy while the rising modal tone B1 received the highest. Tone C2 in particular was most likely to be identified as the high tones A1 or B1 when originally uttered in noise. The findings call into question whether hyper-articulation always leads to better speech intelligibility, especially for tonal languages.
Voicing-, voiceless-, and non-glimpses in speech intelligibility prediction
Authors: Sun Yinglun , Tang Yan
Published: April 2023

The number of speech spectro-temporal (S-T) regions escaping from noise masking, known as “glimpses,” is proportional to speech intelligibility in noise. Previous studies have demonstrated that intelligibility can be estimated by calculating the glimpse proportion (GP). More recent evidence revealed that the contribution of glimpses to intelligibility differs in the energy level of the glimpsed regions, and that even non-glimpsed regions play a non-negligible role in speech perception in noise. This study incorporated the voicing-viceless information in estimating intelligibility using glimpses. Before computing the GP, the counts of raw glimpsed regions or those with energy above the mean noise level were weighted according to the voicing-voiceless status of a frame where the glimpses were detected. Evaluated using speech signals processed to have thirteen glimpse compositions in both temporally stationary and fluctuating noise maskers, the linear correlation between model predictions and listeners' word recognition rates increased from 0.76 to 0.80 for weighted GP, and from 0.89 to 0.92 for weighted high-energy GP. Further taking the contribution from non-glimpsed regions into account in the model improved the correlation to 0.95, suggesting that intelligibility in noise can be better predicted when the contributions of different speech regions are finely modelled.
Reducing dimensionality of spectrograms using convolutional autoencoders
Authors: Jenkins William F. , Gerstoft Peter , Chien Chih-Chieh , Ozanich Emma
Published: April 2023

Under the “curse of dimensionality,” distance-based algorithms, such as k-means or Gaussian mixture model clustering, can lose meaning and interpretability in high-dimensional space. Acoustic data, specifically spectrograms, are subject to such limitations due to their high dimensionality: for example, a spectrogram with 100 time- and 100 frequency-bins contains 104 pixels, and its vectorized form constitutes a point in 104-dimensional space. In this talk, we look at four papers that used autoencoding convolutional neural networks to extract salient features of real data. The convolutional autoencoder consists of an encoder which compresses spectrograms into a low-dimensional latent feature space, and a decoder which seeks to reconstruct the original spectrogram from the latent feature space. The error between the original spectrogram and reconstruction is used to train the network. Once trained, the salient features of the data are embedded in the latent space and algorithms can be applied to the lower-dimensional latent space. We demonstrate how lower-dimensional representations result in interpretable clustering of complex physical data, which can contribute to reducing errors in classification and clustering tasks and enable exploratory analysis of large data sets.
Quantification of individual factors impacting measurement of sound
Authors: Koukounian Viken
Published: April 2023

In the science of metrology, various terms—such as trueness, precision, accuracy, repeatability, reproducibility, and bias—are used to describe the statistics describing the distribution of measurement results, to establish understandings of degree of closeness of results, closeness of agreement between results of tests, and so on. Although there are many factors that affect the variability of results from a measurement method, the impact of individual factors is confounded or not sufficiently differentiated from the collective. In the following contribution, the impacts of different measurement methods (e.g., styles and procedural differences), operators, measurement instruments, and architectures (e.g., finishings, furnishings, and fit-outs) are quantified. The results from this work are critical to develop a higher level of understanding of procedural guidance in international standards. Examples of applications benefiting from these insights include the evaluation of ambient acoustic conditions (i.e., background noise and masking sound) and of sound isolation.
Long-term and short term effects of elevated underwater sound on oyster toadfish (Opsanus tau)
Authors: Colbert Benjamin R.
Published: April 2023

The effects of underwater sound on fishes are of increasing concern for managers, regulators, and researchers. While there has been work which demonstrated changes in behavior, these studies have generally evaluated of immediate or near-term responses. Understanding acute changes in behavior is necessary, but questions about long-term responses to underwater sound, including any habituation and the relative influence of environmental conditions versus anthropogenic sound must also be investigated. To further elucidate potential response to chronic underwater vessel generated sound, passive acoustic monitoring was used to measure the response of vocalizing oyster toadfish (Opsanus tau) to vessel sounds within the Chesapeake Bay. An automatic detector was configured which allowed for counting of vessel passages and toadfish vocalizations. The response of vocalizing toadfish individual vessel movement was then evaluated. Next the response of toadfish to elevated sound levels across a 30-day period was measured and compared to short-term response. In addition, the influence of environmental variables and contrasted effects of these on the effects of increased anthropogenic sound was investigated.