bluuebunny/crossref_metadata_2025 huggingface dataset:
When the United States says you do not belong: Suicide‐related thoughts and behaviors among immigrant young adults varying in immigration legal status
Authors: Venta Amanda , Long Tessa , Mercado Alfonso , Garcini Luz M. , Cadenas Germán A.
Published: May 2022

Background

The number of immigrants in the United States and the risk of suicide among minoritized individuals have increased. Little research has examined the impact of immigration legal status on suicide‐related thoughts and behaviors (SRTB), despite theoretical and empirical work suggesting that feelings of burdensomeness and failure to belong (prominent among immigrants) are risk factors.

Methods

We examined a diverse sample of foreign‐born young adults (18–25; N = 366). Data collection utilized the Suicide Behaviors Questionnaire Revised and items probing belongingness and immigration status (undocumented/Deferred Action for Childhood Arrivals (DACA), permanent, and citizen).

Results

DACA/undocumented status was associated with increased SRTB compared with permanent and citizen categories. Increased SRTBs were associated with reduced feelings of acceptance in the United States, increased deportation fears, and increased fear of being harassed or hurt. Of these belongingness variables, only the interpersonal—not feeling welcome in the United States—partially mediated the risk relation between DACA/undocumented immigration legal status and SRTBs, whereas physical and legal threat, like deportation, did not.

Conclusions

Our results highlight the interpersonal nature of SRTB risk in DACA/undocumented immigrants and the need for targeted culture and context‐appropriate interventions, as well as advocacy and policy to reduce risk in this historically marginalized population.
Randomised controlled trial of glucose‐6‐phosphate dehydrogenase deficient versus non‐deficient red blood cell transfusion in patients with hypoproliferative anaemia
Authors: Krajibthong Suphattharachai , Sahntipurna Vachiraphan , Parnsamut Chalisa , Pitakpolrat Patrawadee , Pattanapongsak Walaporn , Watanaboonyongcharoen Phandee , Rojnuckarin Ponlapat
Published: May 2022

Background

Recent studies revealed the glucose‐6‐phosphate dehydrogenase (G‐6‐PD) deficiency prevalence of 7.7–10% among Thai blood donors. Transfusion of red blood cells (RBCs) from these subjects potentially causes haemolysis in recipients.

Methods

RBC units from the National Blood Centre were sampled to assess G‐6‐PD levels using spectrophotometry. Patients with pure underproduction anaemia requiring blood transfusion were randomised to receive G‐6‐PD‐deficient versus normal ABO‐matched RBCs. Pre‐ and 48‐h post‐transfusion indirect bilirubin, haemoglobin, haematocrit, lactate dehydrogenase (LDH) and haptoglobin were measured.

Results

From April 2020 to March 2021, 374 RBC units were tested for G‐6‐PD, and that 25 were found to be G‐6‐PD deficient. Twelve units of G‐6‐PD‐deficient RBCs and 14 units of normal RBCs were given to patients who met the inclusion criteria. The median (interquartile range) increases of indirect bilirubin in G‐6‐PD‐deficient (N = 11) versus normal RBCs (N = 13) were + 0.12 (0.27) versus + 0.01 (1.3) mg/dl, p = 0.030), respectively. The median increases of haemoglobin were 1.00 (0.50) versus + 0.80 (0.95), p = 0.910, respectively. The increases in haematocrit were 2.59 (1.9) versus 2.29 (2.1), p = 0.733, respectively. There were no significant differences in changes of LDH and haptoglobin levels and no transfusion reactions.

Discussion

G‐6‐PD‐deficient packed red cells were associated with mildly elevated indirect bilirubin after transfusion, but there was no observed clinical symptoms.
Probable paraneoplastic leukocytosis in a dog with a gastrointestinal stromal tumor
Authors: Gidcumb Emily M. , Bolton Timothy A. , Trusiano Brie , Zimmerman Kurt L. , Oakes Vanessa J.
Published: May 2022

A 9‐year‐old female spayed Boston Terrier presented for diagnostic investigation of lethargy, poor appetite, weight loss, and a marked leukocytosis. Significant muscle wasting and a palpable abdominal mass were present on physical examination. Abdominal imaging revealed the mass to be of small intestinal origin; consequently, an intestinal resection and anastomosis were performed without complication. The histopathologic diagnosis was a gastrointestinal stromal tumor, verified by immunohistochemical positivity to CD117 (KIT). Two weeks after discharge, the leukocytosis had resolved. Though the exact molecular mediator of the severe leukocytosis was undetermined, resolution following tumor removal suggests a paraneoplastic cause. To the authors' knowledge, this is the first reported case of probable paraneoplastic leukocytosis secondary to a gastrointestinal stromal tumor in the dog. Gastrointestinal tract imaging should be performed when this uncommon hematologic abnormality is present.
Ureteropyeloscopic removal of a nephrolith from a 19 year old Hanoverian gelding
Authors: Moss Alexandra L. , Acutt Elizabeth V. , Ullal Tarini , Applegate Tanya J. , Hackett Eileen S.
Published: May 2022

Objective

To describe the ureteropyeloscopic removal of a nephrolith in a horse.

Animals

A 19 year old Hanoverian gelding with history of urolithiasis requiring surgical intervention.

Study design

Case report

Methods

The horse presented with signs of abdominal straining and stranguria. A proximal urethral calculus was palpable externally within the perineal urethra. Perineal urethrostomy (PU) at the location of the urethral calculi was performed to remove the urethral obstruction. Left nephrolithiasis was then treated by endoscopic retrieval, inserting the endoscope through the PU. The procedures were performed over 2 consecutive days, with the horse standing and sedated. Medical therapy included antimicrobial and anti‐inflammatory treatment.

Results

The ureteropyeloscopic removal of a nephrolith from the left renal pelvis was completed. No complications were appreciated following the procedure, and the horse was able to return to athletic activity within 2 weeks. The horse had no further clinical signs referable to urinary dysfunction 7 months later.

Conclusion

Ureteropyeloscopic removal of a nephrolith from the renal pelvis is technically feasible in the equine patient and preserves function of the affected kidney. The availability of a treatment that maintains renal function is a distinct benefit over unilateral nephrectomy, particularly when treating a condition that frequently involves both kidneys.
Multiwalled Carbon Nanotube Reinforced Composites for Strengthening Adhesive Tubular Joints
Authors: Joshi Preeti , Tyagi R. K.
Published: May 2022

Adhesives are widely used for making joints in various structures. A strong and durable joint is required for heavy duty structures. Various reinforcement materials are being used for improving the strength of adhesives. Carbon nanotubes (CNTs) are observed as strong reinforcing material in the development of nanocomposites. In this work multiwalled carbon nanotube (MWCNT), reinforced epoxy adhesives are used for strengthening tubular joints in pipe sections. Continuum modeling approach using finite element method is applied for the design and analysis of tubular joint. Stresses at the joint section are analyzed under tensile and torsion loading conditions. Effect of geometrical parameters such as adhesive thickness, overlap length and pipe material in the strength of the joint is determined. The results obtained can be used to optimize the joint. The simulation technique used in this work is found to be useful for the composite pipe designers for designing joints for pipe applications. A comparison of von mises stresses for MWCNT-reinforced epoxy adhesive and epoxy adhesive indicates that MWCNT filled epoxy joints provide higher bonding strength than the epoxy joints. The present model is validated with Lubkin and Reissner’s model. The plot of normalized stresses for both models reveals that the finite element results are in good agreement with the theoretical results.
Helmholtz-Rayleigh Interdisciplinary Silver Medal in Architectural Acoustics and Engineering Acoustics 2022: George L. Augspurger
Authors: Augspurger George L.
Published: May 2022

The Silver Medal is presented to individuals, without age limitation, for contributions to the advancement of science, engineering, or human welfare through the application of acoustic principles, or through research accomplishment in acoustics.
FORUM: Remote testing for psychological and physiological acoustics
Authors: Peng Z. Ellen , Waz Sebastian , Buss Emily , Shen Yi , Richards Virginia , Bharadwaj Hari , Stecker G. Christopher , Beim Jordan A. , Bosen Adam K. , Braza Meredith D. , Diedesch Anna C. , Dorey Claire M. , Dykstra Andrew R. , Gallun Frederick J , Goldsworthy Raymond L. , Gray Lincoln , Hoover Eric C. , Ihlefeld Antje , Koelewijn Thomas , Kopun Judy G. , Mesik Juraj , Shub Daniel E. , Venezia Jonathan H.
Published: May 2022

Acoustics research involving human participants typically takes place in specialized laboratory settings. Listening studies, for example, may present controlled sounds using calibrated transducers in sound-attenuating or anechoic chambers. In contrast, remote testing takes place outside of the laboratory in everyday settings (e.g., participants' homes). Remote testing could provide greater access to participants, larger sample sizes, and opportunities to characterize performance in typical listening environments at the cost of reduced control of environmental conditions, less precise calibration, and inconsistency in attentional state and/or response behaviors from relatively smaller sample sizes and unintuitive experimental tasks. The Acoustical Society of America Technical Committee on Psychological and Physiological Acoustics launched the Task Force on Remote Testing (https://tcppasa.org/remotetesting/) in May 2020 with goals of surveying approaches and platforms available to support remote testing and identifying challenges and considerations for prospective investigators. The results of this task force survey were made available online in the form of a set of Wiki pages and summarized in this report. This report outlines the state-of-the-art of remote testing in auditory-related research as of August 2021, which is based on the Wiki and a literature search of papers published in this area since 2020, and provides three case studies to demonstrate feasibility during practice.
Waveguide invariant in a gradual range- and azimuth-varying waveguide
Authors: Song Wenhua , Gao Dazhi , Li Xiaolei , Kang Dexiang , Li Yuzheng
Published: May 2022

Experimental data indicate that in a sloped area, the value of β abruptly changes before and after a given source arrives at the closest point of approach to the hydrophone, which has not been previously reported. The adiabatic approximation is employed to explain the above abrupt change in β, and it is found that the azimuthal variance in the sound path is the reason for this phenomenon. Simulations are performed to confirm the model and experimental data, and perfect agreement is achieved. This work suggests that β should be carefully set in related applications in a sloped area.
Influence of environmental perturbations on acoustic signals in the 2021 New England Shelf Bread Acoustics experiment
Authors: DeCourcy Brendan J. , Lin Ying-Tsong , Gawarkiewicz Glen , Johnson Jennifer , Zhang Weifeng G.
Published: May 2022

During the 2021 New England Shelf Break Acoustics (NESBA) experiment, real-time hydrodynamic and acoustic models deployed on shipboard high-performance computers (HPC) predicted acoustic signals sent and received within the NESBA mooring network. The hydrodynamic model incorporated field measurements of the physical environment in real time. While the resulting comparisons between models and received data produced similar patterns for strong arrivals, the cause for variation in weaker arrivals by detailed physical oceanographic variability is not trivial to deduce. In this presentation, the influence of perturbations to sub-bottom properties and small-scale water column variability on signals in the NESBA acoustic model is explored using sensitivity kernels. The predicted acoustic signal uncertainty will be further compared with measured variability to evaluate the model skill to capture acoustic fluctuation in the varying shelf break environment. [Work supported by the Office of Naval Research.]
Focused ultrasound effects on the glioblastoma immune microenvironment
Authors: Sun Tao , McDannold Nathan J.
Published: May 2022

Focused ultrasound (FUS) is an attractive method of treating neurological diseases, such as glioblastoma (GBM). An accumulating body of evidence has confirmed the efficacy and safety of using FUS with systematically circulating microbubbles, which operate as acoustic enhancers, to temporarily open the blood-brain barrier for drug delivery. However, there is very limited knowledge of how immune cell respond to mechanical stimuli such as FUS, particularly in the complex immune microenvironments of brain tumors. Here, we report FUS immunomodulation effects may also include the enhanced recruitment and activation of other mononuclear phagocytes in murine models of GBM in tests with or without monoclonal antibody-based passive immunotherapy. Flow cytometry, immunohistochemistry, and in vitro cell co-culture studies were performed for immunoprofiling and immune effector determination. In murine GBM models, our results demonstrated that FUS enhanced antigen presentation behaviors of tumor-associated macrophages without affecting the microglia. FUS also reprogrammed the macrophages locally towards the anti-cancer phenotype. Taken together, our results offer new evidence in FUS immunomodulation on the myeloid compartment of the brains in GBM mouse models.
Quantifying the role of microstreaming in sonoporation
Authors: Aron Miles , Stride Eleanor P.
Published: May 2022

Cavitation microstreaming has been identified as an important mechanism underpinning sonoporation. The reported evidence includes experimental observation of the permeabilization of non-adherent cells or vesicles in microstreaming and theoretical and experimental estimates of the fluid shear stress required to induce pore formation in cell membranes and/or the activation of membrane components such as ion channels. The aim of this study was to assess the relative contribution of microstreaming to sonoporation observed in vitro with adherent cells, as commonly used in drug delivery studies. Streak velocimetry measurements were performed within a microfluidic cell of the microstreaming around a contrast agent microbubble driven at 0.5 and 1MHz and peak negative pressures up to 1MPa. The results suggest that, for the cell densities and microbubble concentrations typically reported in sonoporation studies, only a very small proportion of cells within a typical culture device would be exposed to sufficiently high shear stresses to be permeabilised. This finding is inconsistent with reported results for drug delivery efficiency and suggests that microstreaming may not be the dominant mechanism of sonoporation in this type of experiment.
Active metamaterial for realizing odd micropolarity
Authors: Huang Guoliang
Published: May 2022

Materials made from active, living, or robotic components can display emergent properties arising from local sensing and computation. Here, we realize a freestanding active metabeam with piezoelectric elements and electronic feed-forward control that gives rise to an odd micropolar elasticity absent in energy-conserving media. The non-reciprocal odd modulus enables bending and shearing cycles that convert electrical energy into mechanical work, and vice versa. The sign of this elastic modulus is linked to a non-Hermitian topological index that determines the localization of vibrational modes to sample boundaries. At finite frequency, we can also tune the phase angle of the active modulus to produce a direction-dependent bending modulus and control non-Hermitian vibrational properties. Our continuum approach, built on symmetries and conservation laws, could be exploited to design others systems such as synthetic biofilaments and membranes with feed-forward control loops.
Bandgap and mode shape tuning of piezoelectric metamaterial
Authors: Baz Amr M.
Published: May 2022

The mode shape of piezoelectric metamaterials is tuned by manipulating spatially the electrical boundary conditions of the piezo-elements, in a desired and controlled manner, in order to tailor the wave propagation characteristics through these metamaterials. The proposed concept relies on the fact that open-circuit piezo-elements made of lead-zirconate-titanate (PZT4) are twice as stiff as the same piezo-elements when operating under short-circuit conditions. Appropriate switching of the boundary conditions of the different piezo-elements between open and short-circuit conditions results in any desirable spatially distribution of the stiffness over the entire metamaterial volume. With such capabilities, it would be possible to control the bandgap characteristics of the metamaterial. But, more importantly, it would also be feasible to alter the mode shape characteristics of the metamaterial in order to control the magnitude and direction of wave propagation. This in effect enables controlling or breaking the reciprocity characteristics of the metamaterial. A finite element model (FEM) is developed to model the bandgap and mode shape characteristics of one-dimensional piezo-metamaterial. The effect of various switching strategies on the location and spectral width of the bandgap characteristics is illustrated. Furthermore, the switching strategies are also shown to influence the mode shapes, energy flow, and reciprocity characteristics of the piezo-metamaterial.
Modeling musician diffraction for artificially excited clarinet directivity measurements
Authors: Bellows Samuel D. , Leishman Timothy W.
Published: May 2022

Directivity measurements of musical instruments have many applications in musical, audio, and architectural acoustics. Typical measurement methods include artificially excited instruments and instruments played by live musicians. While recent advances in directivity measurement techniques enable higher resolutions for played instruments, the results are still limited in bandwidth and repeatability compared with directivity results from artificially excited instruments. However, artificially excited instruments typically neglect musician diffraction and absorption. This work compares possible approaches for representing musician diffraction in artificially excited clarinet measurements to improve their directivity results for room simulations or auralizations.
Measured high-resolution directivities of guitar amplifiers
Authors: Edelman Rachel C. , Anderson Brian E. , Bellows Samuel D. , Leishman Timothy W.
Published: May 2022

Guitar amplifiers comprise specialized powered loudspeakers with distinct configurations and directivity characteristics. Recently, the authors measured the directivities of six guitar amplifiers using a new measurement system. The system employs a rotating semicircular microphone array in an anechoic chamber, with 2522 unique microphone positions over a surrounding sphere (i.e., 5-deg resolution in both the polar and azimuthal angles). This presentation will describe the measurement and processing procedures and compare the measured results to those produced by theoretical directivity models. An online archival database provides easy access to the guitar amplifier data and other directivity data from the human voice, played musical instruments, and other sound sources. The data are available in several commonly used file formats and should provide valuable information for many applications, including spatial audio, architectural acoustics modeling, and microphone placement.
On the possibility of electrostatically generated infrasound during thunderstorms
Authors: Sabatini Roberto , Riousset Jeremy , Snively Jonathan B. , Liu Ningyu
Published: May 2022

Acoustic emissions from lightning discharges are usually attributed to two mechanisms. The audible part of their spectrum mainly results from the shock wave generated by the heating of the lightning channel. On the other hand, the infrasonic component is associated with the conversion to sound of the electrostatic energy stored in the thundercloud. While there is a broad scientific consensus on the former mechanism, the latter process is still controversial. The electrostatic mechanism was proposed by C. T. R. Wilson in 1921 and can be summarized as follows. Due to the electrostatic repulsion of the charged particles, the pressure within a thundercloud is lower than outside. At discharge, the electrostatic field collapses, and the sudden air volume contraction produces an acoustic pulse. This work examines the existing theoretical models of the electrostatic mechanism with the data observed for thundercloud dimensions, charge densities, and total charges. Our results show that, although possible, this mechanism, as currently described, cannot explain observations. Our findings might support the hypothesis that the heating of the lightning channel is responsible for the generation of both infrasound and audible sound. However, a definitive answer remains precluded and requires a better understanding of cloud formation and electrification processes.
Anomalous vertical sound propagation and the ground-blocking of turbulence
Authors: Wilson D. Keith , Ostashev Vladimir , Kamrath Matthew J. , Hart Carl R.
Published: May 2022

Scattering by turbulence leads to random scintillations and coherence loss of sound waves, among other impacts. In a recent experiment involving transmissions from a 130-m tower to microphones on the ground [Kamrath et al., J. Acoust. Soc. Am. 149(3), 2055–2071 (2021)], the turbulence impacts on phase variances were shown to be considerably smaller for vertical and slanted paths than theoretically predicted. The primary cause is likely ground blocking of the turbulence: since the sound waves are impacted most strongly by the turbulent velocity fluctuations in the direction of propagation, and the ground blocks large vertical motions, the turbulence impacts are relatively weakened for vertical paths. An approach is described for including the ground blocking in the turbulence spectrum and, thus, in acoustic scattering calculations. The anisotropic propagation effect could possibly be used to measure the relative strengths of vertical and horizonal velocity fluctuations in the near-ground atmosphere.
Comparison of infrasound emissions from tornadic and non-tornadic storms
Authors: Frazier Garth , Waxler Roger M. , Talmadge Carrick , Hetzer Claus , Buchanan Hank
Published: May 2022

At a previous ASA meeting (Spring 2019), some results corresponding to application of maximum likelihood estimation with the complex Wishart distribution to direction-of-arrival of infrasound from tornadic storms were presented. In this presentation, updated results are presented and compared with estimation of direction-of-arrival of infrasound from two non-tornadic storms that were measured with the same infrasound arrays. One of these storms was similar to the tornadic storm in that it consisted of numerous isolated storm cells with frequent lightning. The other storm was significantly different in that it was a well-organized squall line that produced only limited lightning. The tornadic storm yielded very well-defined direction-of-arrival tracks in contrast to the non-tornadic storms.
How does knowledge of acoustics guide the parameterizations of gravity waves?
Authors: Millet Christophe , Lott Francois , de la Camara Alvaro
Published: May 2022

Describing the statistics of gravity wave (GW) fields represents a major motivation for both current research on atmospheric GWs and long-range infrasound propagation. In practice, the probability density functions (PDF) of the momentum fluxes are estimated combining observations, numerical modelling, and theory. Numerical models (such as WRF) show that the PDFs vary in a robust way relative to the background local wind speed. For non-orographic GWs, these PDFs are approximated as lognormal distributions, with characteristics found to depend on the background wind speed. Studies show that some trends are not observed using a state-of-the-art stochastic parameterization of GWs, unless the phase velocities of GW sources (essentially tropospheric) are dramatically changed. As the vertical wavelength and the phase velocity are related to each other, such changes also affect the interaction between infrasound and lower-stratospheric GWs. Consequently, significant efforts have been made to use ground-based acoustic sensors for characterizing the GW sources, including the use of neural networks. This approach provides a promising way to describe the statistics of GW sources from ground-truth infrasound events and an additional constraint to tune stochastic parameterizations of GWs.
A novel paradigm to define functional spatial boundaries
Authors: Ozmeral Erol J. , Higgins Nathan
Published: May 2022

One approach to studying an individual’s binaural function is to measure speech reception ability for spatially separated compared to co-located competing speech streams. This spatial-release-from-masking (SRM) task has been widely adopted due to its capacity to detect abnormal binaural function, but it has its limitations in interpreting individual spatial abilities. Here, we introduce a modified SRM task that directly measures the needed spatial separation between target and maskers to achieve a specific SRM. Stimuli were presented from 24 speakers in the free field using an equal power panning method. Normal-hearing listeners (n = 10) were tasked with identifying digits in a target stream of monosyllabic words always presented from the front. Initial measures were made using the classic SRM paradigm in which two opposite-gender masker streams were either presented from the front (co-located), or symmetrically from 30° (fixed-separation), to determine a speech reception threshold (SRT; in dB target-to-masker ratio). Based on the co-located SRT, the task then adaptively tracked the separation angle needed to achieve 6-dB SRM. Results showed for most listeners, a 10-dB SRM at 30° separation and an average spatial boundary less than 30 degrees when fixed at 6-dB SRM. [Work supported by NIH NIDCD R21DC017832 to EJO.]
Deep neural network models of speech-in-noise perception for hearing technologies and research
Authors: Borjigin Agudemu , Kokkinakis Kostas , Bharadwaj Hari , Stohl Josh
Published: May 2022

Widespread adoption of artificial intelligence has yet to occur in the hearing field. Hearing technologies, such as cochlear implants (CIs), provide limited benefits of noise reduction, even with current state-of-the-art signal processing strategies. Recent developments in machine learning have produced deep neural network (DNN) models achieving remarkable performance in speech enhancement and source separation tasks. However, there are currently no commercially available CI audio processors that utilize DNN models for noise suppression. Furthermore, the current research community lacks a computational tool to match the complexity of natural auditory processing. To address these gaps, we implemented two DNN models: a recurrent neural network (RNN)—a lightweight template model for speech enhancement, and the SepFormer—the current top-performing speech-separation model in the literature. The DNN models resulted in significant improvements in terms of objective evaluation metrics, as well as intelligibility scores obtained with CI users at different signal-to-noise ratios. Given their flexibility and good performance on complex tasks, these models can also be used to generate hypotheses about speech-in-noise perception and serve as richer substitutes for models commonly used in research. This work serves as a proof-of-concept and a guide for the next steps towards integrating DNN technology into hearing technologies and research.
Development of an electromechanical test system and acoustical metrics to predict impacts of hearing protection devices on sound localization
Authors: Argo Theodore F. , Anderson David A. , Brown Andrew D. , Greene Nathaniel , Jerding Jennifer
Published: May 2022

Hearing protection devices (HPDs) such as earplugs and earmuffs can protect users from dangerously high acoustical pressures but also distort cues important for the spatial localization of sounds, likely through spectral distortions associated with occlusion of the pinnae. Evaluation of the degree to which an HPD distorts localization cues is essential for critical situations where users must be protected from high pressures but maintain spatial awareness. Automated testing offers several prospective advantages over human subject testing including cost, speed, and repeatability. In this paper, we describe an electromechanical system using a rotating manikin test fixture and a speaker on a track to simulate a hemispheric speaker array. The sound source localization impact of an HPD is estimated by comparing test signals recorded by the manikin with and without an HPD in place. Test results, as a function of sound source azimuth and elevation in the virtual speaker array, and as an average across locations, are shown for a variety of HPDs. Results are compared to an initial set of parallel measurements of sound localization during HPD use in human subjects.
Turn the music down! Repurposing assistive listening broadcast systems to remove nuisance sounds
Authors: Corey Ryan M. , Singer Andrew C.
Published: May 2022

Many public venues, such as theaters and houses of worship, use assistive listening systems that broadcast a copy of the sound being played over a public address system to the listening devices of patrons with hearing loss. While these wireless systems are generally intended to amplify sound for listening device users, they can also be used to cancel nuisance sounds, such as loud background music that makes conversation difficult. In this work, we demonstrate a binaural listening device that uses an assistive listening system transmitter and receiver to attenuate music played through loudspeakers while preserving speech sounds from nearby talkers. A set of adaptive filters tracks the acoustic transfer functions from the loudspeakers to the earpiece microphones, predicts the music signal received by each earpiece, and subtracts that predicted signal from the mixture signal of the corresponding earpiece. The binaural adaptive system tracks changes in the unwanted music signal as the user moves while preserving the acoustic and spatial cues of the desired speech sounds. [Work supported by the Intelligence Community Postdoctoral Research Fellowship Program, National Science Foundation, and Discovery Partners Institute.]
Substructured optimization for a speakerphone design task
Authors: Luu Matthew , Wixom Andrew S.
Published: May 2022

This work explores the use of substructures and parallelized optimization techniques in order to design speakerphone casings, the same problem considered by Berggren et al. [in 10th World Congress on Structural and Multidisciplinary Optimization (2013)]. For this work, a simplified model consisting of a 1D beam model with enforced vibration at one end is used to represent the supporting structure of the speaker and microphone of the device. The thickness of the supporting structure is varied in order to reduce coupling between the speaker and microphone. Minimization of the structural vibration in the microphone region over frequencies between 300 and 3400 Hz is examined for optimization. A substructuring approach using spectral elements and Legendre polynomials for the thickness profile reduces the computation cost such that many evaluations of the model may be obtained in a reasonable time. The Python optimization library PyGMO is used to distribute optimization tasks over multiple CPUs in order to further accelerate the design process. The approach is shown to successfully optimize a thickness distribution targeting the frequencies of interest while reducing computation costs and is compared to previously published results for this example problem.
Effects of two-talker child speech on novel word learning in preschool-age children
Authors: Grieco-Calub Tina M. , Gordon Katherine R. , Lowry Stephanie L. , Cortez Diana M.
Published: May 2022

Preschool-age children’s recognition of speech is more susceptible to the presence of background noise than that of older children. Because younger children rely on access to speech to learn their native language, children who are poorer at resolving degraded speech may be at risk for delayed vocabulary development. To test this relation directly, we are implementing a retrieval-based word learning task in preschool-age children. Children are taught four novel disyllabic words either in a quiet condition or in the presence of two-talker child speech (TTS) at + 10 dB-signal-to-noise ratio. Children’s performance is quantified by the number of words and the number of phonological features recalled immediately after training and after a 5-min delay. Children also complete tests of familiar word recognition in TTS, verbal working memory, and vocabulary knowledge. In this presentation, we will compare children’s word-learning outcomes between the quiet and TTS conditions and evaluate the influence of children language skills on their performance. We predict that children will have greater phonological precision of the novel words in quiet than in the presence of TTS. We also predict that children’s verbal working memory skills and vocabulary knowledge will relate to greater learning, regardless of listening condition.
School-age children show poor use of spatial cues in reverberation for speech-in-speech perception
Authors: Peng Z. Ellen
Published: May 2022

Understanding speech is particularly difficult for children when there is competing speech in the background. When the target and masker talkers are spatially separated, as compared to co-located, the access to corresponding auditory spatial cues can provide release from masking, resulting in an intelligibility gain for speech-in-speech perception. When tested in free-field environments, previous work showed that children demonstrate adult-like spatial release from masking (SRM) by 9–10 years of age. However, in indoor environments where most critical communications occur such as classrooms, reverberation distorts the critical auditory spatial cues that lead to reduced SRM among adults. Little is known about how children process distorted auditory spatial cues for SRM to aid speech-in-speech perception. In this work, we measure SRM in children in virtual reverberant environments that mimic typical learning spaces. We show free-field measurements overestimate SRM maturation in realistic indoor environments. Children show a more protracted development of SRM in reverberation, likely due to immaturities in using distorted auditory spatial cues.
Do cochlear-implanted children benefit from voice cue differences for understanding speech in speech masker?
Authors: Baskent Deniz
Published: May 2022

Differences in voice cues of mean fundamental frequency (F0) and vocal-tract length (VTL) between a target and masker speech can help a listener to segregate the two, and enhance speech intelligibility. Postlingually deafened and implanted adult CI users have difficulties in perceiving F0 and VTL, and this possibly contributes to challenges in understanding speech in presence of a speech masker. Previous research showed that speech-on-speech understanding is not yet adult-like in normal-hearing (NH) children of school age, as this skill seems to develop over many years. Yet, like NH adults, NH children do seem to benefit from the voice cue differences in some situations. In the case of CI children, a number of factors could influence intelligibility of speech with speech maskers. Prelingually deafened and implanted CI children develop auditory skills primarily based on spectrotemporally degraded speech input, which could lead to different developmental patterns compared to NH children. On the other hand, the CI children would benefit from the optimal brain plasticity period for learning, which could lead to different perceptual patterns compared to CI adults. In this talk, I will present data from multiple projects with children and adults at our lab to investigate these potential expectations.
Spatial room impulse response measurement and post-processing for virtual reproduction of a stereo sound system
Authors: Rusk Zane T. , Vigeant Michelle C.
Published: May 2022

Spatial room impulse responses (SRIRs) characterize the spatial, temporal, and spectral properties of the sound field received at a particular location in a room for a given source-receiver configuration. SRIRs can be captured using spherical microphone arrays and are useful both for evaluating the acoustic performance of a space and in applications where it is desired to auralize the sound field being characterized with varying signals being played from the source. In this work, SRIRs were measured in a living room (mid-frequency RT approximately 0.4 s) using an mh acoustics Eigenmike em32 as the receiver and both a studio monitor loudspeaker and a subwoofer as the sources. Studio monitor placements replicated a left-right-center stereo monitoring configuration, with the subwoofer on the floor below the center loudspeaker, while attempting to avoid source and receiver placement on estimated modal planes in the room. Details of the post-processing used to finalize the SRIRs for use as a virtual stereo sound system will be presented, including cross-over filtering, tuning, and correction of the overall frequency response to a curve that is favorable for in-room loudspeaker listening. Measurement system details, SRIR data visualizations, and RT estimates will also be discussed.
Ultrasound-assisted membrane permeabilization of endothelial cells under flow conditions
Authors: Memari Elahe , Hui Fiona , Helfield Brandon
Published: May 2022

Ultrasound-stimulated microbubbles have been shown a feasible approach for localized therapeutic delivery. As applications of this technique span many anatomical sites, so too do the local fluid dynamics experienced by the circulating microbubbles and the adjacent endothelial cells. Our objective was to assess the relative effectiveness of endothelial cell sonoporation as a function of flow conditions. Human umbilical vein (HUVECs) or human brain endothelial cells (HBECs) were cultured as a monolayer in flow chamber slides connected to a fluidic system and placedupon an acoustically-coupled microscope. A suspension of diluted lipid-encapsulated microbubbles and propidium iodide (PI), used as a sonoporation marker, was constantly perfused over the monolayer at either 5 or 30 ml/min. Cells were treated with 1 MHz ultrasound (PRI= 1 ms, 20 cycles, duration = 2 s), and the video-microscopy data were quantified offline to assess the number of PI-positive cells. Our results demonstrate a marked increase in sonoporation efficiency at 30 ml/min as compared to 5 ml/min in both endothelial cell lines under identical acoustic conditions (9.7-fold increase and 2.3-fold increase for HUVECs and HBECs respectively, p < 0.001). Our results suggest the local fluid flow environment plays a role in US-mediated endothelial perforation efficiency and can modulate treatment strategies.
Asymptotic modal analysis application to a cavity-plate system to predict sound transmission loss
Authors: Sung Shung H. , Nefske Donald J.
Published: May 2022

The asymptotic modal analysis (AMA) method has previously been developed to predict the high-frequency dynamic response of structural and acoustical systems [Sung et al., Asymptotic Modal Analysis of Structural and Acoustical Systems (Morgan & Claypool Pub., 2021)]. In the AMA method, the dynamic response is obtained as the asymptotic limit of the classical modal analysis (CMA) solution as the averaged response in large frequency bands. In previous work, the AMA method has been applied to uncoupled individual structural and acoustical systems. In the asymptotic limit, the AMA results for individual structural and acoustical systems have been shown to approach the corresponding statistical energy analysis (SEA) results. The AMA method has also previously been applied to a coupled cavity-plate system to predict the high frequency response for piston-like excitation of the plate. In this paper, the AMA method is applied to a cavity–plate system subjected to random excitation of the plate to predict the sound transmission loss into the cavity. The AMA results in the asymptotic limit for the cavity-plate system are shown to approach the corresponding CMA and SEA results. In addition, the AMA method is able to predict the spatial distribution of the plate and cavity responses.
Multi-material stimuli-responsive hydrogels with optically induced actuation
Authors: Tholen Haley , Harne Ryan L.
Published: May 2022

A vision for soft, autonomous materials entails synthesis of multiple senses in multifunctional materials where material response requires sensitivity to external stimuli. Stimuli-responsive hydrogels are of particular interest for optically induced mechanical response due to the ability to transform external stimuli into large, reversible shape change. Specifically, temperature-responsive hydrogels are broadly used and can be designed to achieve deformation through the photothermal effect as a result of surface plasmonic resonance of gold nanoparticles. Here, a multi-material stimuli-responsive hydrogel network with embedded gold nanoparticles is demonstrated in a unit cell pattern with anisotropic swelling behavior in response to visible light. Reversible, anisotropic swelling leads to bending motion that contributes to the development of soft, autonomous materials.
Quiet power: Exploring the feasibility of a noise-mitigating, thermoacoustic energy harvester
Authors: Biswas Samarjith , Manimala James M.
Published: May 2022

The thermoacoustic effect provides a means to convert acoustic energy to heat and vice versa without the need for moving parts. This enables the realization of mechanically robust, noise mitigating energy harvesters, although there are limitations to the power-to-volume ratio achievable. The mechanical, thermal, and geometric properties of the porous stack that forms a set of acoustic waveguides in thermoacoustic devices are key to its performance. In this feasibility study, first, various 4-in. diameter ceramic and polymeric stack designs are evaluated using a custom-built thermoacoustic test rig. Influence of stack parameters such as material, length, location, porosity, and pore geometry are correlated to simulations using DeltaEC, a software tool based on Rott’s linear approximation. An acousto-thermo-electric transduction scheme is employed to harvest useable electrical power using the best performing stack. Steady-state peak voltage generated was 33.5 mV for a temperature difference of 34 °C between thehot and cold sides of the stack at an acoustic excitation frequency of 117.5 Hz. Further investigations are underway to establish structure-performance relationships by extracting scaling laws for power-to-volume ratio and frequency-thermal gradient dependencies.
Connections between unit cells in locally resonant metamaterials and their impact on the effectiveness of noise mitigation by its base structure
Authors: Juros Klara , Kras Aleksander
Published: May 2022

Locally resonant metamaterials (LRS) for sound and vibration mitigation have been a widely investigated topic in the field of acoustic in recent years. Many articles and projects describe fundamental problems of LRS design, numerical simulation, and laboratory measurements. However, there is a noticeable knowledge gap between laboratory prototypes and the mass production (development for a wide-scale implementation) of metamaterials structures. In general, the LRS prototypes require specific boundary conditions, for example, equal spacing between the individual resonators and separate attachment of each resonator to its base. These conditions allow for many simplifications in calculations. At the same time, these boundary conditions create a problem when it comes to the mass production of the LRS structures. Creating a connection between adjacent resonators would allow easier postprocessing of structures ex. attaching the structure to the base and keeping specified distances between resonators. This project investigates the possibilities of creating connections between adjacent unit cells and their influence on the simulation and measurement results. The effect on the simulated band gaps and sound transmission loss is investigated at the stage of numerical simulations. The prototypes of structures are 3D printed and tested. The laboratory measurement results are compared with simulations and further discussed.
Lung ultrasound: State of the art and future directions
Authors: Demi Libertario
Published: May 2022

Following the COVID-19 pandemic, lung ultrasound (LUS) received growing attention as the need for a safe, point-of care, cost-effective, and widely available imaging solution was crucial. However, when performed with clinical scanners, LUS remains limited to the subjective and qualitative interpretation of artifacts and imaging patterns. This negatively affects accuracy and reproducibility. During the COVID-19 pandemic, we have developed a standardised LUS acquisition protocol and scoring system, aiming at minimizing the impact of several confounding factors. This approach has proven prognostic value and is capable of stratifying patients based on their risk of worsening. Moreover, the availability of an extensive and standardised dataset (772,780 LUS frames) allowed us to develop AI approaches capable of analysing LUS data automatically. Results from a multicentric study conducted on 220 patients will be presented. Next, beyond what can be achieved with clinical scanners, we are also pioneering the development of novel ultrasound solutions dedicated to the lung. To provide with a forward-looking view on the future of LUS, the latest results from numerical and in vitro- studies focused on unveiling the physical phenomena at stake will be discussed in detail, together with the latest results from the first clinical studies on quantitative lung ultrasound spectroscopy.
Why did wind instruments stop evolving?
Authors: Braasch Jonas
Published: May 2022

Adolphe Sax invented the last widely spread orchestral wind instrument in 1846, and the saxophone has hardly changed since its inception. Also, outside of classical music, wind instruments have not evolved with very few exceptions in popular music, like the melodica. The latter was popular in the mid 20th century, because it was one of the cheapest instruments with a piano-style keyboard before mass-produced electronic keyboards. Since its inception, jazz drew from traditional orchestral wind instruments that were invented long before jazz came up. They were easily available as they were widely spread in military ensembles. This presentation looks into the factors that stalled the evolution of mainstream wind instruments during the 19th century, such as instrument affordability, practice habits, conservatory education practices, standardization, and cultural identification. While individual instrument makers and musicians continue to develop fundamentally new wind instruments, they no longer exceed experimental status. Instead, widespread innovations now focus on electronic and digital musical instruments.