bluuebunny/crossref_metadata_2025 huggingface dataset:
Requirement of acoustical engineering discipline in building designs
Authors: Razavi Zohreh
Published: October 2018

While assurance of professional design and commitment for field review from all engineering disciplines and an architect is required, acoustical review is not mandated by legislations or By-laws. Although sound control review requirement is mandated by most By-Laws, this is at an architect’s discretion to decide whether retaining an acoustical engineer for a sound control review for a project is required or not. Architects, even those focused on sustainable and human-centered design have often overlooked acoustical quality as a design goal. The launch of programs like the “WELL Building Standard” which includes several features related to acoustics, and addition of the “acoustic performance credit to LEED v4” are signs that the green building industry is starting to promote acoustic performance an integral component of sustainable design. Though architects are more aware of the importance of acoustics, achieving good acoustic performance is still overlooked. Once acoustical compliance letter is mandated during building permit, the importance of acoustics in building designs will be recognized.
Impact of stimulus bandwidth on the estimate of the upper-frequency limit of hearing in toothed whales
Authors: Houser Dorian S. , Coffinger Sean P. , Mulsow Jason , Finneran James J. , Burkard Robert F.
Published: October 2018

No consensus on the stimuli used in toothed whale hearing tests using evoked potential methods currently exists. However, stimulus bandwidth should directly affect determination of the upper-frequency limit (UFL) of hearing because of the steep reduction in hearing sensitivity at frequencies immediately below the UFL—the broader the stimulus bandwidth, the greater the amount of spectral “splatter” into lower frequencies where hearing is more sensitive. To test this hypothesis, variability in auditory evoked potential thresholds to tone-pips (with variable bandwidth) and amplitude-modulated tones was determined in dolphins near their UFL of hearing and ½ to 1 octave below where hearing is more sensitive. Subjects included both normal and hearing-impaired dolphins. At frequencies where hearing was sensitive and the audiogram was relatively flat, negligible changes in the hearing threshold with changing stimulus bandwidth were observed. Conversely, thresholds near the UFL of hearing declined with increasing stimulus bandwidth, regardless of whether dolphins had normal hearing or hearing impairment, and resulted in broadened hearing bandwidth estimates. Thus, it is recommended that stimulus bandwidth be reported in hearing tests where the UFL is tested since stimulus bandwidth affects thresholds through spectral splatter into lower frequency bands where hearing is more sensitive.
Dependence of bottlenose dolphin (Tursiops truncatus) auditory brainstem responses on noise burst rise time, amplitude, and envelope shape
Authors: Jones Ryan A. , Finneran James J. , Mulsow Jason , Burkard Robert F.
Published: October 2018

A series of experiments examined the dependence of dolphin auditory brainstem response (ABR) peak amplitudes and latencies by stimulus level, rise times, and envelope shape. Stimuli were spectrally “pink” noise bursts with frequency content from 10 to 160 kHz, rise times that varied from 32 μs to 4 ms, and plateau sound pressure levels from 102 to 138 dB re 1 μPa. Cosine and cosine-cubed rise (and fall) envelopes were tested, and results were compared to those obtained for dolphins using noise bursts with linear rise envelopes [Finneran et al., J. Acoust. Soc. Am. 143, 2914–2921 (2018)]. Results for the cosine and cosine-cubed envelopes showed that ABR peak amplitudes were a function of envelope sound pressure at the end of a fixed integration window of approximately 260 μs. This is congruent with the previous findings for linear envelopes. The ABR peak latencies for the cosine and cosine-cubed envelopes were dependent on the second derivative of the envelope pressure function, as opposed to the first derivative of the pressure function for linear envelopes. These data are consistent with single-unit and nearfield response data for terrestrial mammals. [Work supported by Navy Living Marine Resources and SSC Pacific Naval Innovative Science and Engineering Programs.]
The production and reception of underwater sound in Hawaiian monk seals (Neomonachus schauinslandi)
Authors: Sills Jillian , Parnell Kirby , Reichmuth Colleen
Published: October 2018

The endangered Hawaiian monk seal is a primitive phocid (true) seal endemic to the tropical Hawaiian Islands. At present, there is a lack of substantive bioacoustic information available for this species, with no formal descriptions of underwater vocalizations and limited data concerning underwater hearing. To address these knowledge gaps, we are working to better understand species-typical auditory capabilities and sound production by thoroughly evaluating a single individual living in human care. A mature male monk seal was trained to perform an auditory go/no-go signal detection task in water. Detection thresholds were measured for narrowband tones across the frequency range of hearing to generate a full underwater audiogram. Additionally, an acoustic recorder was placed in this monk seal’s living enclosure for a full year, enabling characterization of his underwater repertoire and seasonal trends in vocal behavior. This study presents the first examination of underwater vocalizations in Hawaiian monk seals, provides insight into the perceptual abilities of this species and the evolution of underwater hearing within the phocid lineage, and enables improved assessments of noise effects on these vulnerable seals. [Work supported by Navy’s Living Marine Resources Program.]
Underwater acoustic target recognition using graph convolutional neural networks
Authors: Sabara Razi , Jesus Sergio
Published: October 2018

Motivated by recent progress in signal processing on graphs and convolutional neural networks, we have developed an underwater acoustic target recognition system based on graph convolutional neural networks. We evaluate our framework by application to various real-world datasets and validate its effectiveness. Our experiments demonstrate that the proposed approach achieves high classification accuracy.
Exploring matrix and tensor factorization for discovering latent structures in large echosounder datasets
Authors: Lee Wu-Jung , Staneva Valentina
Published: October 2018

Moored autonomous echosounders are increasingly popular as an integrated component in ocean observing systems for measuring biological response to environmental changes. Different from ship-based observations, these large echo datasets often lack concurrent ground truth information from net or optical samples and reliable calibration, both of which are required for conventional analysis routines. However, even though accurate inference of organism abundance is not possible in such scenarios, rich spatio-temporal structures exist in the data and may be exploited to capture variation of migration patterns of different animal groups in the water column. Here, we explore the use of unsupervised matrix and tensor factorization approaches to analyze the long-term echo data sets from the Ocean Observatories Initiative (OOI) network. The data stretch in multiple dimensions, including time, space, and frequency. We restructure the echo data to explore latent structures at different temporal scales using different factorization formulations. Outputs from different methods are compared among one another and with those from conventional echo analysis routines. The results show the importance of augmenting generic factorization formulations with temporal and spatial continuity constraints for biologically meaningful analysis of large echosounder datasets.
Analytical solution for elliptic shear standing wave pattern in a bounded transversely isotropic viscoelastic material
Authors: Guidetti Martina , Royston Thomas J.
Published: October 2018

Dynamic elastography methods—based on photonic, ultrasonic, or magnetic resonance imaging—are being developed for quantitatively mapping the shear viscoelastic properties of biological tissues, which are often altered by disease and injury. These diagnostic imaging methods involve analysis of shear wave motion in order to estimate or reconstruct the tissue’s shear viscoelastic properties. Most reconstruction methods to date have assumed isotropic tissue properties. But, application to tissues like skeletal muscle and brain white matter with aligned fibrous structure resulting in local transverse isotropic mechanical properties would benefit from analysis that takes into consideration anisotropy. A theoretical approach is developed for the elliptic shear wave pattern observed in transverse isotropic materials subjected to axisymmetric excitation normal to the fiber axis. This approach, utilizing Mathieu functions, is enabled via a transformation to an elliptic coordinate system with isotropic properties and a ratio of minor and major axes matching the ratio of shear wavelengths perpendicular and parallel to the plane of isotropy in the transverse isotropic material. The approach is validated via finite element analysis cases studies. This strategy of coordinate transformation to equivalent isotropic systems could aid in analysis of other anisotropic tissue structures. (Grant support: NIH AR071162.)
Shear wave elastography with combined high spatial and temporal frequency excitations
Authors: Urban Matthew W. , Kijanka Piotr
Published: October 2018

Shear wave elastography is a method for quantitatively measuring the mechanical properties of soft tissues. Shear wave attenuation is high in soft tissues and increases with frequency. In a recent work, high resolution and accuracy can be reached at higher temporal frequencies. To combat the high shear wave attenuation and to obtain higher accuracy and lower variability, we propose to combine acoustic radiation force excitations that have multiple push beams and high temporal frequencies. Multiple push beams were generated with multiple focused beams and multiple intersecting unfocused beams. Measurements made with tonebursts of ultrasound with length 200 μs repeated at 500 and 1000 Hz were compared against a single toneburst. Measurements were made in commercial homogeneous and heterogeneous phantoms. Wave velocity images were reconstructed from the acquired data. The accuracy and variance were evaluated in the homogeneous phantoms. The contrast and accuracy were evaluated in the heterogeneous phantoms. In both types of phantoms, the magnitude at selected frequencies will be compared among the different excitations. The frequency bandwidth for each excitation will be compared. This work highlights that the combination of multiple push beams and excitations with high temporal frequencies can be combined for improved imaging in shear wave elastography.
A ray acoustics-based simulation for predicting trans-vertebral ultrasound propagation: Simulation accuracy
Authors: Xu Rui , O'Reilly Meaghan A.
Published: October 2018

The blood-spinal cord barrier (BSCB) prevents drug delivery to spinal cord parenchyma. Focused ultrasound can temporarily increase BSCB permeability in small animal models. The human vertebral column distorts ultrasound foci, preventing clinical translation of this technique. Beamforming must be used to correct focal distortion and may be performed using ray acoustics and patient-specific preoperative CT scans. We evaluate the simulation accuracy of ray acoustics, applied to trans-vertebral ultrasound propagation, through comparison with experiment. Trans-vertebral ultrasound propagation was measured for a spherically focused transducer geometrically focused to the centre of individual thoracic vertebral foramen. Simulation pressures were compared to experiment pressures. Simulation error in voxel pressure was evaluated using root-mean-square error, and was similar to error in a water-only case. Average simulation error across all measurements and simulations in maximum pressure location and weighted >50% focal volume location were 2.3 mm and 1.5 mm, respectively. Simulation error is small relative to the dimensions of the transducer focus (4.9 mm full width half maximum), the spinal cord (8–10 mm diameter), and vertebral canal diameter (15–20 mm diameter), suggesting that ray acoustics may be sufficiently accurate for ultrasound beamforming to the vertebral foramen.
Feasibility of using ultrasound with microbubbles to purify cell lines for immunotherapy application
Authors: Matula Thomas , Sapozhnikov Oleg A. , Ostrovsky Lev , Brayman Andrew , Kucewicz John , MacConaghy Brian , De Raad Dino
Published: October 2018

Cell-based immunotherapies exploit cell surface antigens to identify and purify cell lines. Fluorescence-based sorters require large sample volumes and are too costly for small labs. Magnetic sorters require enzymatic digestion to remove magnetic particles. We propose to label cells with antibody-conjugated microbubbles (MBs) and selectively sort them using ultrasound. After sorting, the MBs can be removed by a small overpressure. TargeStar-SA microbubbles (MBs) were conjugated to leukemia cells expressing CD7 antigens. Conjugated cell suspensions were placed in a flow with erythrocytes (which lack CD7) and imaged under magnification. Cell motion was quantified with or without ultrasound insonation. The acoustic radiation force (ARF) acting on a cell-MB pair was modeled by assuming the driving force is associated with the MB, and the viscous drag is due to the larger cell. A separate observation of cell-MB rotation caused by the ARF was explained by considering the torque on the cell, where adherent MBs act as point forces. Under insonation, tagged cells were observed to rotate to align with the ARF, and to move in the direction of the ARF. If a tagged cell was adherent to the coverslip, it only rotated. The model for rotation-only behavior fit well with the data. Under flow, tagged leukemia cells were deflected by ultrasound, while erythrocytes were unaffected. These initial studies suggest a new way for isolating and sorting cells. [Funded by LSDF #3292512, RBBR 17-02-00261, NIH P01 DK43881, and NSBRI via NASA NCC 9-58.]
Shape stability of an encapsulated microbubble undergoing translational motion
Authors: Liu Yunqiao , Calvisi Michael L. , Wang Qianxi
Published: October 2018

Encapsulated microbubbles (EMBs) are associated with a variety of important diagnostic and therapeutic medical applications, including sonography, drug delivery, and sonoporation. The nonspherical oscillations, or shape modes, of EMBs strongly affect their stability and acoustic signature, and thus are an important factor in the design and utilization of EMBs. Under acoustic forcing, EMBs often translate with significant velocity, which can excite shape modes, yet few studies have addressed the effect of translation on the shape stability of EMBs. To investigate this phenomenon, an axisymmetric model is developed for the case of small shape oscillations. The exterior fluid is modeled as potential flow using an asymptotic analysis. Viscous effects within the thin boundary layer at the interface are included, owing to the no-slip boundary condition. In-plane stress and bending moment due to the encapsulation are incorporated into the model through the dynamic boundary condition at the interface. The evolution equations for radial oscillation, translation, and shape oscillation of an EMB are derived. These equations are solved numerically to analyze the shape mode stability of an EMB and a gas bubble subject to an acoustic, traveling plane wave. The findings demonstrate the counterintuitive result that translation more readily destabilizes an EMB than an uncoated gas bubble. The main factor responsible for mediating this translation-induced interfacial instability is the no-slip condition at the encapsulating membrane.
Heuristic finite element models of the Japanese Koto
Authors: Sanadzadeh Iran , Coaldrake Angela K.
Published: October 2018

Modeling a traditional, hand-carved performance-grade Japanese koto presents many challenges. A COMSOL Multiphysics finite element model of the instrument, based on CAT scan data, is the most rigorously accurate solution to date. However, a substantially less computationally intensive idealized box model, for example, can provide qualitative assessment of its performance. This paper discusses a COMSOL model based on the physical properties of a solid plank of Australian paulownia wood, its validation, and its elaboration into an idealized but unstable hollow box with internal struts and sound holes of varying geometries. It then reports on the development of the next stage model which has 12 cross-sections lofted along a spline to create curvature as the natural progression towards realism. Comparison of these three models and the complex CAT scan model of the koto is presented. It shows that the box and lofted models are useful in qualitatively interpreting the results of the complex model. Isotropic models, as used in the literature, were unsuccessful in predicting responses, but using best available approximations for anisotropic elastic constants was helpful. Finally, each stage was able to provide timely feedback to inform the development of the next stage model and guide experimentation.
Future trends in noise control technology
Authors: Bolton J. S.
Published: October 2018

Although acoustics plays an important role in noise control, noise control is arguably more difficult than acoustics owing to the constraints that are usually imposed on noise control solutions by manufacturers. That is, ideally, noise control solutions should occupy no space, weigh nothing, cost nothing, not impact the operation of the device being treated, and remain effective for 20 years without maintenance. Hence, identifying effective noise control solutions is a challenging, multidimensional problem. In this presentation, future trends and opportunities in noise control will be highlighted in four categories: targets, measurement techniques, predictive tools, and noise control methods and materials.
Characterisation of complex fluid media by an angle-scanning ultrasound diffractometer
Authors: Francis Mathew J , Holmes Melvin J. , Povey Malcolm J. , Pinfield Valerie J. , Gower Artur L. , Huang Jinrui , Forrester Derek M. , Parnell William J. , Abrahams Ian D.
Published: October 2018

The characterisation of complex fluid media (particles in liquids) by ultrasound can provide information on the particle size distribution, concentration, and aggregation of the particles. In the Rayleigh scattering regime, systems of liquid particles are dominated by monopole scatter (potentially producing thermal waves), whereas solid particle suspensions are dominated by dipole scatter (producing shear waves); thus the angular dependence of the diffracted field is expected to be different in these cases. Since mode conversion mechanisms are affected by the proximity of particles and thus by the degree of aggregation, the effect of particle type and degree of aggregation is expected to be observed in the angle-dependent signals. We report an experimental investigation of the angle- and frequency-dependent diffracted signal from cylindrical samples (in tubing) of emulsions and suspensions. The experimental results are compared with theoretical predictions using effective homogeneous properties for the complex fluids derived from multiple scattering models. We identify the differences in the diffracted signals for complex media in which the scattering mechanisms are monopole or dipole-dominated.
Robust downhole ultrasonic pitch-catch measurements of compressional and shear wave velocities
Authors: Sakiyama Naoki , Deger Evgeniya , Hori Hiroshi , Houshuyama Shin'ichi , Oshima Atsushi , Nakajima Hiroshi
Published: October 2018

Probing acoustic wave velocities of earth formations, both in azimuth and radius, is important when evaluating anisotropy and/or heterogeneity of the formations. A conventional approach for evaluating these complex formations is to employ a sonic logging tool that operates from approximately 0.1 kHz to 20 kHz with an approximately 600 mm spatial resolution. With these standard sonic tools, evaluating formation acoustic wave velocities with an order smaller spatial resolution to detect thin beds and/or azimuthal variation of formation properties is very challenging. To overcome this challenge, this paper discusses an ultrasonic pitch-catch measurement that can be applied to a downhole acoustic tool. Downhole conditions are typically harsh, especially for ultrasonic frequencies. Thus, a robust measurement system is required that maximizes the signal-to-noise ratio. One of the ways to do this is to minimize the distance between the transmitter and the array receiver (and the receiver-receiver spacings of the array). Numerical modeling corroborated by experimental study indicates such a measurement system can primarily detect refracted compressional waves and surface mode waves related to the pseudo-Rayleigh mode. Characteristics of the pseudo-Rayleigh mode measured with such system and a way to estimate shear wave velocity from the measured mode are discussed.
Acoustic transducer design for active reflection cancellation in a finite volume wave propagation laboratory
Authors: Willard Eli , Haberman Michael R. , van Manen Dirk-Jan , Robertsson Johan O. , Becker Theodor S. , Börsing Nele
Published: October 2018

This report describes the design, fabrication, and experimentally obtained electro-acoustic response of an acoustic transducer suite constructed for use in the Wave Propagation Laboratory (WaveLab) at ETH Zürich. WaveLab aims to immerse a physical acoustic experiment within a real-time numerical environment, by implementing exact boundary conditions (EBCs) [J. Acoust. Soc. Am., 134(6), EL492–EL498, (2013)]. When scale-model ultrasonic experimentation is not possible, a system with EBCs allows for low frequency, reflection-free acoustic measurements in a small physical domain. The physical experiment of the WaveLab facility consists of a water tank measuring only 2 m on a side, while WaveLab’s EBCs are realized through a massive computational engine coupled with a dense array of sensing and emitting acoustic transducers. The transducers are used to sense outgoing acoustic waves and to create a reflection-cancelling surface. Criteria for the transducers are discussed in terms of individual and overall system response. The design parameters and associated models include sensitivity, scattering strength, directivity, frequency response, noise floor, and the dynamic range of the system. The transducer designs and models are presented alongside their physical prototypes and experimental results.
Distributed neural systems for musical time processing
Authors: Fujioka Takako
Published: October 2018

My talk will feature recent MEG and EEG studies for examining time processing, and, together with other findings, discuss how distributed neural systems for musical time work together in managing top-down and bottom-up prediction, ensemble coordination, and learning-induced neuroplasticity. It has been long known that passive listening of metronome-like isochronous stimuli involves auditory cortices for simple prediction of the stimulus interval and detection of changes. Recently, however, more studies are aimed at capturing natural neural dynamics that encode or predict time without such "perturbation" approach. We show that in addition to auditory cortices, various motor-related brain areas contribute to neural oscillatory power modulations in listening to isochronous stimulus, and that beta-band frequency of this modulation may explain benefits of auditory-sensorimotor training in clinical populations with movement impairments. Moreover, modulation patterns can encode stimulus intervals, metric hierarchies in perception and imagery, as well as anticipation of upcoming tempo change (e.g., accelerando and ritardando). Listening paradigm is also used to show neuroplastic changes in naïve subjects after short-term piano training in the reward-related systems. Of further interest is frontal lobe's contribution to musical ensemble coordination sensitive to player's role asymmetry and agency (e.g., human vs. computer).
Dual-frequency sound-absorbing metasurface based on visco-thermal effects with frequency dependence
Authors: Jeon Wonju , Ryoo Hyeonbin
Published: October 2018

We propose an acoustic metasurface with near-perfect absorption at two frequencies and design it by using two-dimensional periodic array of four Helmholtz resonators in two types. By considering how fluid viscosity affects acoustic energy dissipation in the narrow necks of the Helmholtz resonators, we obtain effective complex-valued material properties that depend on frequency and on the geometrical parameters of the resonators. We furthermore derive the effective acoustic impedance of the metasurface from the effective material properties and calculate the absorption spectra from the theoretical model, which we compare with the spectra obtained from a finite-element simulation. As a practical application of the theoretical model, we derive empirical formulas for the geometrical parameters of a metasurface that would yield perfect absorption at a given frequency. Whereas previous works on metasurfaces based on Helmholtz resonators aimed to absorb sound at single frequencies, we use optimization to design a metasurface composed of four different Helmholtz resonators to absorb sound at two target frequencies.
An investigation into the direct control of the effective material properties of a fluid medium using active noise control
Authors: Tan Joe , Cheer Jordan , Daley Stephen
Published: October 2018

Acoustic metamaterials are subwavelength-engineered structures that can exhibit behaviour not seen in conventional materials. The effective material properties for acoustic metamaterials are the bulk modulus and density. Negative effective material properties can create band gaps, where wave propagation is forbidden. Hence, acoustic metamaterials can achieve high levels of noise control performance. Active control has been combined with passive acoustic metamaterials to enhance the level of attenuation or broaden the bandwidth of the band gap. However, the width of the band gaps for these materials are still limited by the use of resonators. This study will investigate whether active control can be employed to directly minimise the effective material properties, which requires an optimization procedure. To begin to understand this optimization problem, the effective material properties have been calculated as a function of the real and imaginary parts of the control source strength at various frequencies for monopole and dipole sources. The resulting error surfaces demonstrate that the two configurations could achieve negative effective material properties; however, the cost functions are not always convex without constraints. Therefore, to adaptively manipulate the effective material properties using an active control system would require the development of an advanced optimization procedure.
Acoustic-like behavior in periodic metal structures
Authors: Norris Andrew , Su Xiaoshi
Published: October 2018

Pentamode materials are of interest for acoustic metamaterials because of their property of having only one elastic mode, similar to the hydrostatic response of an acoustic fluid. This static property does not take into account dynamic frequency dependent effects related to the necessary spatial inhomogeneity in the structural realization. In this talk, we argue that pure pentamode behavior is not desirable, and instead AMM users should focus on the one-wave dynamic response. Experience with metal structures designed to provide acoustic properties close to those of water using metal structures, e.g., Su et al. (JASA 2017, doi: 10.1121/1.498519), shows that the most useful response is in a one-wave band gap in which shear waves are non-propagating. Surprisingly, the one-wave region is generally broadband relative to the cutoff frequency of the shear waves at low frequencies, and is non-dispersive, with constant phase speed over the one-wave gap. The talk will attempt to explain these surprising and unexpected features using numerical and analytical results. The latter include an approximation of the dynamic effective properties of 2D and 3D metallic structures displaying broadband one-wave regions using simplistic models.
Magnetoactive acoustic metamaterials
Authors: Wang Qiming
Published: October 2018

Acoustic metamaterials with negative constitutive parameters (modulus and/or mass density) have shown great potential in diverse applications ranging from sonic cloaking, abnormal refraction and superlensing, to noise canceling. In conventional acoustic metamaterials, the negative constitutive parameters are engineered via tailored structures with fixed geometries; therefore, the relationships between constitutive parameters and acoustic frequencies are typically fixed to form a 2D phase space once the structures are fabricated. Here, by means of a model system of magnetoactive lattice structures, stimuli-responsive acoustic metamaterials are demonstrated to be able to extend the 2D phase space to 3D through rapidly and repeatedly switching signs of constitutive parameters with remote magnetic fields. It is shown for the first time that effective modulus can be reversibly switched between positive and negative within controlled frequency regimes through lattice buckling modulated by theoretically predicted magnetic fields. The magnetically triggered negative-modulus and cavity-induced negative density are integrated to achieve flexible switching between single-negative and double-negative. This strategy opens promising avenues for remote, rapid, and reversible modulation of acoustic transportation, refraction, imaging, and focusing in subwavelength regimes.
Studying vocal fold non-stationary behavior during connected speech using high-speed videoendoscopy
Authors: Naghibolhosseini Maryam , Deliyski Dimitar , Zacharias Stephanie , de Alarcon Alessandro , Orlikoff Robert
Published: October 2018

Studying voice production during running speech can provide new knowledge about the mechanisms of voice production with and without disorder. Laryngeal high-speed videoendoscopy (HSV) systems are powerful tools for studying laryngeal function and, if coupled with flexible fiberoptic endoscopes, they can provide unique possibilities to measure vocal fold vibration with high temporal resolution during connected speech. Hence, we can measure the non-stationary behaviors of the vocal folds, such as the glottal attack and offset times in running speech. In this study, a custom-built flexible fiberoptic HSV system was used to record a “Rainbow Passage” production from a vocally normal female. Automated temporal and spatial segmentation algorithms were developed to determine the time stamps of the vibrating vocal folds and the edges of the vocal folds during phonation. The glottal attack time and offset times were then measured from the temporally and spatially segmented HSV images. The amplification ratio was computed during the phonation onset and the damping ratio was calculated at the offset of sustained portion of phonation. These measures can be used to describe the laryngeal mechanisms of voice production in connected speech.
Systematic analysis of fluid-structure-acoustic interactions in an ex-vivo porcine phonation model
Authors: Semmler Marion , Berry David , Schützenberger Anne , Döllinger Michael
Published: October 2018

Background: The phonation process is a complex interaction of different components, namely, the airflow from the lungs, the mucosal tissue in the larynx, and the resulting acoustic signal. From clinical experience, it is assumed that the presence of a pre-phonatory gap, oscillation asymmetries, and aperiodicities constitute detrimental factors to the resulting voice quality. In order to gain an in-depth understanding of the cause-effect chain and enable effective therapeutic measures, the crucial elements of the process need to be studied in isolation. Materials & Methods: The presented experimental set-up allows a systematic control and monitoring of the individual components of the excised porcine larynx. Varying degrees of asymmetric adduction, pre-phonatory gap size and flow rate reproduce irregular oscillation patterns associated with pathologic voice production. Results: The statistical analysis based on k-means clustering allows the identification of structural and aero-dynamic factors which influence voice quality. In addition to an increase in glottal closure and oscillation symmetry, an increase in glottal flow resistance produced a beneficial effect on the acoustic output signal and the closely coupled subglottal pressure. Conclusion: The clinical applicability and therapeutic value of these insights must be assessed in further studies.
Using convolutional neural networks on perceptual and spectral features: Classification experiments on the TREX’13 dataset
Authors: LeBlanc Tara J. , Fawcett John
Published: October 2018

Distinguishing objects of interest on the seafloor from clutter remains a key problem facing the automatic target recognition (ATR) community. Because scattering at high frequencies relates more to the geometry of the scatterer, traditional ATR on high frequency imaging sonars is known to suffer in areas of high clutter. Recently, there has been interest in low frequency (1–50 kHz) wideband imaging sonars, because the complex combination of external (geometric) and internal (elastic) scattering that occurs in this frequency range is thought to improve classification in areas of high clutter. This work investigates the classification problem of distinguishing unexploded ordnance (UXO) from clutter using image-based Convolutional Neural Networks on the TREX’13 dataset. This dataset consists of experimental and modelled acoustic backscatter for objects interrogated acoustically at 3–30 kHz across a range of aspects. The model data are used exclusively for training, and the experimental data are used exclusively for testing purposes. The generated feature-set is a combination of acoustic colour and perceptual features, which are derived from modelling how humans perceive timbre. Further in an effort to address the differing amplitude modulations between sets of model and experimental data and improve classified performance, several moving window normalizations will be investigated.
One project begets many: The role of one seminal project in the development of many design solutions (Part 3)
Authors: Miller Gregory A. , Pfeiffer Scott D.
Published: October 2018

In the third and final part of this multi-part paper, computer modeling will be described as a tool for presentation to client groups (often skilled listeners but not expert acousticians). Over the course of the Verizon Hall project, computer models were used to present visual illustrations that explained the acoustic concerns experienced by the orchestra. Starting with this project, Threshold began to develop computer models as tools to translate acoustic phenomena in ways that clients could understand visually and, over time, aurally. The development of customized computer modeling techniques has further supported communication with non-acousticians, and examples of these techniques will be presented.
The micromechanics and bioacoustic behaviour of Bunaea alcinoe moth scales
Authors: Shen Zhiyuan , Neil Thomas R. , Robert Daniel , Drinkwater Bruce W. , Holderied Marc W.
Published: October 2018

Through the 65 million year acoustic arms race between moths and bats, different moth species have evolved different defence strategies against bat echolocation. For non-toxic moth species without hearing capability, passive acoustic camouflage is thought to be the most efficient way to evade bat predation. Being the elementary building blocks covering moth wing surfaces, scales have been hypothesized as the main organ creating such acoustic camouflage. There is, however, no understanding for the relation between scale microstructure and wing acoustic performance. This report represents the first effort to numerically and experimentally characterize moth scale biomechanics and vibrational behaviour. 3D microstructures of Bunaea alcinoe moth scales have been characterized using various microscopies. A parameterized finite element model has been built to replicate the double-layered perforated scale bio-nanomaterial. Both experimental and numerical analyses have proved that the first three resonance frequencies of a single scale lie within the bat echolocation frequency range. Here, we propose numerical models that explain how the resonances can contribute to the acoustic performance of wings. This study contributes to the on-going discussion of the evolution of ultrasonic camouflage in moths. We aim to use our findings to generate biomimetic light-weight noise mitigation materials.
Physical Activity for Disabled Youth: Hidden Parental Labor
Authors: Goodwin Donna L. , Ebert Amanda
Published: October 2018

Locating suitable, inclusive community physical activity programs for disabled children can be challenging for parents. The aim of this study was to uncover everyday hidden labor experienced by parents, as they sought inclusive physical activity opportunities for their children. Focus group interviews with eight families of youth aged 13–19 years were completed using an interpretative phenomenological case study research approach. Four themes, interpreted through the framework of relational ethics, captured their experiences: (a) inclusion is immensely effortful; (b) judged by their impairments, not their possibilities; (c) ongoing education needed to open doors and sustain participation; and (d) the guilt of staying home. Reliance on hidden parental labor highlighted an exclusion agenda in community, accentuated by ableist belief systems.
Accelerometer-Measured Physical Activity and Sedentary Behavior: A Cross-Sectional Study of Brazilian Older Adults
Authors: dos Santos Carla Elane Silva , Manta Sofia Wolker , Maximiano Guilherme Pereira , Confortin Susana Cararo , Benedetti Tânia Rosane Bertoldo , d’Orsi Eleonora , Rech Cassiano Ricardo
Published: October 2018

Background: To examine the level of physical activity and sedentary behavior (SB), measured with accelerometers, in older adults from a city in southern Brazil according to sociodemographic and health characteristics. Methods: The sample consisted of 425 older adults (≥63 y) from the EpiFloripa Aging Study. Light physical activity (LPA), moderate to vigorous physical activity (MVPA), and SB were measured with accelerometers over a period of 7 days. Results: The older adults spent two-thirds of the time of use in SB, one-third in LPA, and only 2.1% (95% confidence interval, 1.8–2.2) in MVPA. In the final adjusted model, lower levels of MVPA were observed for women, as well as higher SB and lower LPA and MVPA for those with higher age. There were also trends toward prolonged SB and lower LPA when participants had a higher educational level and toward lower MVPA with higher body mass index. Conclusions: Constant monitoring of physical activity levels and SB using objective measures is recommended and interventions should be directed at the groups most exposed to excessive SB and low levels of MVPA.
Effects of 9 Months of Martial Arts Training on Cardiac Autonomic Modulation in Healthy Children and Adolescents
Authors: Suetake Vinícius Y.B. , Franchini Emerson , Saraiva Bruna T.C. , da Silva Anne K.F. , Bernardo Aline F.B. , Gomes Rayane L. , Vanderlei Luiz Carlos M. , Christofaro Diego G.D.
Published: October 2018

Purpose: The aim of the study was to evaluate the cardiac autonomic modulation after 9 months of martial arts practice in healthy children and adolescents. Method: The study included 59 children and adolescents who were divided into 3 groups: judo, Muay Thai, and control. Heart rate variability was measured by a heart rate monitor, model Polar RS800CX. The intervention occurred twice a week on nonconsecutive days, lasting 60 minutes each session. A 1-way analysis of variance was used to compare participants at baseline. The comparisons between groups at baseline and after the intervention were carried out by a 2-way analysis of variance for repeated measures. Results: After 9 months of intervention, significant increases were observed for root mean square successive differences, with higher values post compared with baseline (19.5%; P = .04). For SD1, an interaction effect was observed, with increased posttraining values compared with baseline (24.1%; P = .04) for the judo group. Qualitative analysis of the Poincaré plot showed greater dispersion of RR intervals, mainly beat to beat, after the judo intervention compared with the baseline. The Muay Thai and control groups presented no improvement. Conclusion: After 9 months of intervention, there were increases in cardiac autonomic modulation of children and adolescents participating in judo training. The practice of martial arts, such as judo, can be encouraged from an early age to improve cardiovascular system functioning, possibly providing protection against cardiovascular problems.
Catalysis-tunable Heusler alloys in selective hydrogenation of alkynes: A new potential for old materials
Authors: Kojima Takayuki , Kameoka Satoshi , Fujii Shinpei , Ueda Shigenori , Tsai An-Pang
Published: October 2018

Heusler alloys are well known in other fields but little known in catalysis, where we demonstrate that they have great potential.
Strongly interacting dipolar-polaritons
Authors: Rosenberg Itamar , Liran Dror , Mazuz-Harpaz Yotam , West Kenneth , Pfeiffer Loren , Rapaport Ronen
Published: October 2018

Strong electrical interactions between hybrid light-matter quasiparticles in semiconductors can lead to new quantum applications.
Nonthrombogenic, stretchable, active multielectrode array for electroanatomical mapping
Authors: Lee Wonryung , Kobayashi Shingo , Nagase Masase , Jimbo Yasutoshi , Saito Itsuro , Inoue Yusuke , Yambe Tomoyuki , Sekino Masaki , Malliaras George G. , Yokota Tomoyuki , Tanaka Masaru , Someya Takao
Published: October 2018

The stretchable and active multielectrode array successfully measured electrocardiography of rat during blood exposure.
Ultrafast manipulation of mirror domain walls in a charge density wave
Authors: Zong Alfred , Shen Xiaozhe , Kogar Anshul , Ye Linda , Marks Carolyn , Chowdhury Debanjan , Rohwer Timm , Freelon Byron , Weathersby Stephen , Li Renkai , Yang Jie , Checkelsky Joseph , Wang Xijie , Gedik Nuh
Published: October 2018

Topological defects, potential information carriers, were written into and erased from a solid with femtosecond light pulses.
Atomic-level structure engineering of metal oxides for high-rate oxygen intercalation pseudocapacitance
Authors: Ling Tao , Da Pengfei , Zheng Xueli , Ge Binghui , Hu Zhenpeng , Wu Mengying , Du Xi-Wen , Hu Wen-Bin , Jaroniec Mietek , Qiao Shi-Zhang
Published: October 2018

Atomic-level structure engineering potentially revolutionizes the design of capacitive oxide materials.
Cell surface polysaccharides of
Bifidobacterium bifidum
induce the generation of Foxp3
+
regulatory T cells
Authors: Verma Ravi , Lee Changhon , Jeun Eun-Ji , Yi Jaeu , Kim Kwang Soon , Ghosh Ambarnil , Byun Seohyun , Lee Choong-Gu , Kang Hye-Ji , Kim Gi-Cheon , Jun Chang-Duk , Jan Gwenaël , Suh Chang-Hee , Jung Ju-Yang , Sprent Jonathan , Rudra Dipayan , De Castro Cristina , Molinaro Antonio , Surh Charles D. , Im Sin-Hyeog
Published: October 2018

Cell wall components of probiotic bacterium
Bifidobacterium bifidum
drive induction of regulatory T cells in the gut.
Role of oxidants in microbial pathophysiology
Authors: Miller R A , Britigan B E
Published: October 2018

Reactive oxidant species (superoxide, hydrogen peroxide, hydroxyl radical, hypohalous acid, and nitric oxide) are involved in many of the complex interactions between the invading microorganism and its host. Regardless of the source of these compounds or whether they are produced under normal conditions or those of oxidative stress, these oxidants exhibit a broad range of toxic effects to biomolecules that are essential for cell survival. Production of these oxidants by microorganisms enables them to have a survival advantage in their environment. Host oxidant production, especially by phagocytes, is a counteractive mechanism aimed at microbial killing. However, this mechanism may be contribute to a deleterious consequence of oxidant exposure, i.e., inflammatory tissue injury. Both the host and the microorganism have evolved complex adaptive mechanisms to deflect oxidant-mediated damage, including enzymatic and nonenzymatic oxidant-scavenging systems. This review discusses the formation of reactive oxidant species in vivo and how they mediate many of the processes involved in the complex interplay between microbial invasion and host defense.
Biology of Isospora spp. from humans, nonhuman primates, and domestic animals
Authors: Lindsay D S , Dubey J P , Blagburn B L
Published: October 2018

Coccidial parasites of the genus Isospora cause intestinal disease in several mammalian host species. These protozoal parasites have asexual and sexual stages within intestinal cells of their hosts and produce an environmentally resistant cyst stage, the oocyst. Infections are acquired by the ingestion of infective (sporulated) oocysts in contaminated food or water. Some species of mammalian Isospora have evolved the ability to use paratenic (transport) hosts. In these cases, infections can be acquired by ingestion of an infected paratenic host. Human intestinal isosporiasis is caused by Isospora belli. Symptoms of I. belli infection in immunocompetent patients include diarrhea, steatorrhea, headache, fever, malaise, abdominal pain, vomiting, dehydration, and weight loss, blood is not usually present in the feces. The disease is often chronic, with parasites present in the feces or biopsy specimens for several months to years. Recurrences are common, Symptoms are more severe in AIDS patients, with the diarrhea being more watery. Extraintestinal stages of I. belli have been observed in AIDS patients but not immunocompetent patients. Treatment of I. belli infection with trimethoprim-sulfamethoxazole usually results in a rapid clinical response. Maintenance treatment with trimethoprim-sulfamethoxazole is needed because relapses often occur once treatment is stopped.
Yersinia pestis--etiologic agent of plague
Authors: Perry R D , Fetherston J D
Published: October 2018

Plague is a widespread zoonotic disease that is caused by Yersinia pestis and has had devastating effects on the human population throughout history. Disappearance of the disease is unlikely due to the wide range of mammalian hosts and their attendant fleas. The flea/rodent life cycle of Y. pestis, a gram-negative obligate pathogen, exposes it to very different environmental conditions and has resulted in some novel traits facilitating transmission and infection. Studies characterizing virulence determinants of Y. pestis have identified novel mechanisms for overcoming host defenses. Regulatory systems controlling the expression of some of these virulence factors have proven quite complex. These areas of research have provide new insights into the host-parasite relationship. This review will update our present understanding of the history, etiology, epidemiology, clinical aspects, and public health issues of plague.