bluuebunny/crossref_metadata_2025 huggingface dataset:
Multilateral Methods, Substitution Bias, and Chain Drift: Some Empirical Comparisons
Authors: Melser Daniel , Webster Michael
Published: December 2020

Multilateral methods are increasingly being used in the computation of official price indexes such as the consumer price index (CPI). This reflects the growing use of scanner data by statistical agencies and the fact that fixed‐based or chained price comparisons perform poorly in this context. A range of multilateral approaches have been pursued by different statistical agencies. Yet, it can be shown that some of these methods, at least theoretically, could suffer from substitution bias. We investigate this as well as the drivers of chain drift. We adopt a simulation‐based approach using actual scanner data prices with the corresponding quantities being generated assuming constant elasticity of substitution (CES) preferences. We find that most methods systematically deviate from the exact CES benchmark index. This is even the case for the superlative index methods, which should not exhibit substitution bias. Interestingly, we also find significant chain drift even in the exact CES indexes. We argue this reflects life cycle pricing and particularly run‐out sales at the end of a product's life.
Mathematics identity and achievement among Black students
Authors: Gonzalez Lidia , Chapman Shawnda , Battle Juan
Published: December 2020

Employing data from the National Center of Educational Statistics' High School Longitudinal Study and utilizing critical race theory and intersectionality as theoretical frameworks, this article interrogates the relationship between mathematics identity and math success for a nationwide sample of Black secondary school students. More specifically, hierarchical regression modeling is employed to examine the relative impact of math identity, demographic variables, and school/parent social capital variables on the math grade point averages of this sample. The article ends with a discussion of specific steps for teaching mathematics that put the identity of those from traditionally marginalized communities at the center of mathematics instruction. Thus making experiences, histories, culture, and abilities essential elements of students' learning, that are to be supported and built upon.
Income, Equality, and Economic Development
Authors: Montenegro Alvaro
Published: December 2020

Objective

This article proposes a simple and operational definition of development that combines the level of income per capita with a measure of income distribution.

Method

Following the definition, an economic development index is constructed by averaging income per capita with Gini coefficients from the well‐known SWIID database.

Results

A ranking of countries is obtained for the proposed index, and it is compared to the rankings produced using the United Nations’ Human Development Index (HDI) and the GDP per capita.

Conclusion

The results for the proposed index show interesting differences with the rankings produced by the HDI and the economists’ favorite GDP per capita.
Holes in the wall: Examining gaps in knowledge in child and adolescent mental health in Tanzania – Scoping review
Authors: Clarke Ellisiv , Boshe Judith , Spencer‐Rogers Amelia , Jacques Cara , Walker Richard
Published: December 2020

Objectives

To perform scoping review of the existing literature available specific to child and adolescent mental health in Tanzania.

Methods

An extensive literature search of PubMed, Scopus, MEDLINE and EMBASE was undertaken to identify studies that focussed specifically on mental illness in children and young people in Tanzania. This included neurological and functional disorders, affective disorders, psychosis, epidemiological, intervention and treatment‐based studies. Qualitative analysis of the studies was then undertaken to assess what is currently known about the subject and how reliable this information is and to identify areas for further research.

Results

Of 23 studies were included in the final synthesis, which could be broadly split into studies focussing on the prevalence and incidence of child and adolescent mental illness, hypothesised causes and correlations, identified treatments and interventions and qualitative studies of human experience.

Conclusion

There is a dearth of published research regarding child and adolescent mental health in Tanzania. Although some high‐quality studies allow us good insight into the epidemiology of mental illness, interventional studies are often small and low‐power, and significant correlational relationships are yet to be drawn. There is significant scope for further child and adolescent mental health research in Tanzania.
Dimerization of the ETO1 family proteins plays a crucial role in regulating ethylene biosynthesis in Arabidopsis thaliana
Authors: Gu Shin‐Yuan , Lo Wan‐Sheng , Wu Shaw‐Jye , Wang Long‐Chi
Published: December 2020

ETHYLENE OVERPRODUCER1 (ETO1), ETO1‐LIKE1 (EOL1), and EOL2 are members of the Broad complex, Tramtrack, Bric‐a‐brac (BTB) protein family that collectively regulate type‐2 1‐aminocyclopropane‐1‐carboxylic acid synthase (ACS) activity in Arabidopsis thaliana. Although ETO1 and EOL1/EOL2 encode structurally related proteins, genetic studies suggest that they do not play an equivalent role in regulating ethylene biosynthesis. The mechanistic details underlying the genetic analysis remain elusive. In this study, we reveal that ETO1 collaborates with EOL1/2 to play a key role in the regulation of type‐2 ACS activity via protein–protein interactions. ETO1, EOL1, and EOL2 exhibit overlapping but distinct tissue‐specific expression patterns. Nevertheless, neither EOL1 nor EOL2 can fully complement the eto1 phenotype under control of the ETO1 promoter, which suggests differential functions of ETO1 and EOL1/EOL2. ETO1 forms homodimers with itself and heterodimers with EOLs. Furthermore, CULLIN3 (CUL3) interacts preferentially with ETO1. The BTB domain of ETO1 is sufficient for interaction with CUL3 and is required for homodimerization. However, domain‐swapping analysis in transgenic Arabidopsis suggests that the BTB domain of ETO1 is essential but not sufficient for a full spectrum of ETO1 function. The missense mutation in eto1‐5 generates a substitution of phenylalanine with an isoleucine in ETO1F466I that impairs its dimerization and interaction with EOLs but does not affect binding to CUL3 or ACS5. Overexpression of ETO1F466I in Arabidopsis results in a constitutive triple response phenotype in dark‐grown seedlings. Our findings reveal the mechanistic role of protein–protein interactions of ETO1 and EOL1/EOL2 that is crucial for their biological function in ethylene biosynthesis.
COVID‐19 associated with severe autoimmune hemolytic anemia
Authors: Jacobs Jeremy , Eichbaum Quentin
Published: December 2020

Background

Autoimmune hemolytic anemia (AIHA) has many known disease associations, including autoimmune, lymphoproliferative, and certain infectious diseases, as well as various medications. Studies have found that severe cases of coronavirus disease 2019 (COVID‐19) may be associated with coagulopathies; however, the potential association with AIHA is not clear.

Case Report

A patient with no known risk factors or underlying predisposition for developing AIHA presented to a hospital with vague symptoms and profound anemia with a complicated blood bank evaluation. She was found to have COVID‐19 and AIHA, for which extensive laboratory testing was performed, including direct antiglobulin tests, elution studies, and cold agglutinin titers, to identify the causative autoantibody. She required multiple blood transfusions and therapeutic interventions before clinical stabilization.

Discussion

AIHA is a complex disease with a spectrum of presentations and clinical severity. Many diseases have been associated with a propensity for developing AIHA; however, there are few cases in the literature of patients with COVID‐19 and AIHA. Most of the reports involve patients with other underlying conditions that are known to be associated with the development of AIHA. The presentation, clinical findings, and therapeutic interventions in a patient with severe AIHA, without other underlying conditions, in the setting of COVID‐19 are discussed.

Conclusions

There are few reports of patients with concurrent COVID‐19 and AIHA, and the association is not clear. Although COVID‐19 has been shown to be associated with coagulopathies, more research is required to determine whether AIHA may also be a potential complication.
Caudal paramedian approach to cryptorchidectomy in 29 small ruminants (2011‐2019)
Authors: Haig Fallon M. , Baird Aubrey N. , Hawkins Jan F. , Moore George E.
Published: December 2020

Objective

To describe a caudal paramedian approach to cryptorchidectomy in small ruminants.

Study design

Retrospective case series.

Animals

Sheep (n = 20) and goats (n = 9) with cryptorchidism.

Methods

Medical records from January 2011 to July 2019 of small ruminants that underwent caudal paramedian cryptorchidectomy at our institution were retrospectively reviewed. Data from animal signalment, operative and postoperative complications, and client satisfaction were evaluated.

Results

Twenty sheep and nine goats underwent caudal paramedian cryptorchidectomy during the study period. The median age of rams was 2 months, and the median age of bucks was 3 months; median weights for rams and bucks were 20.5 kg (range, 14.5‐41.3) and 28.1 kg (range, 12.9‐82), respectively. Cryptorchidism was bilateral in 27.6% (8/29) of cases and unilateral in 72.4% (21/29). Among unilateral cases, 85.7% (18/21) were right sided and 14.3% (3/21) were left sided. Twenty‐four of 29 (82.8%) cases were performed under sedation. One operative complication occurred in a 4‐year‐old 82 kg buck (rate, 3.4% [95% CI: 0.1%–17.2%]). Postoperatively, there were two minor and one major complications (rates, 6.9% [95% CI: 0.8%–22.1%] and 3.4% [95% CI: 0.1%–17.2%], respectively). Long‐term follow‐up (range, 8‐117 months) reports described owner satisfaction and all animals doing well at the time of follow‐up telephone call.

Conclusion

Caudal paramedian approach to cryptorchidectomy was safely performed in small ruminants less than 4 months old.

Clinical significance: Ease of surgical technique, minimal operative and postoperative complications, and owner satisfaction make this a suitable method for cryptorchidectomy.
Assessing phylogeographic variation in the Rosyside Dace (Teleostei, Leuciscidae), a widespread morphologically variable taxon
Authors: Weyand Courtney A. , Piller Kyle R.
Published: December 2020

Clinostomus (Leuciscidae) is a wide‐ranging freshwater fish genus that occurs throughout eastern North America and southern portions of Canada with two species currently recognized: C. elongatus and C. funduloides. A previous taxonomic study of C. funduloides recognized two subspecies (estor and funduloides) and one diagnosed, but undescribed subspecies based on morphological characteristics and geographic distribution. In this study, we used three molecular markers (cytochrome b, S7 intron 1 and growth hormone intron 4) to test the three lineage hypothesis and evaluate genetic variation of C. funduloides across the range using Bayesian inference. Our results indicate that C. funduloides is not monophyletic, as individuals of C. elongatus nest within C. funduloides in both the mtDNA and nDNA phylogenetic analyses, although the position of C. elongatus varies between data sets. In addition, some of the recovered clades are deeply divergent from one another, further supporting the distinctiveness of many of the populations. Overall, these results suggest that subspecies designations are not warranted and a taxonomic revision is needed as Clinostomus is likely more diverse than is currently recognized.
El método jesuita: la formación integral del educando en el caso neogranadino
Authors: del Rey Fajardo, S. J. José
Published: December 2020

La labor jesuítica ha sido uno de los puntos cardinales a la hora de abordar los procesos educativos a nivel mundial, en especial, durante los siglos XIV-XVIII, pues junto a ella se encuentran la historia de las ideas, la filosofía, la religión, la retórica y la gramática, las aspiraciones de una congregación y los planes políticos de diversas naciones. En El método jesuita: la formación integral del educando en el caso neogranadino el autor nos da un contexto histórico rico para pasar a analizar las características de la formación y la docencia de este grupo religioso que tuvo un inmenso alcance. Así, en el interior de estas páginas se propone un diálogo entre tres documentos fundamentales que contienen el alma de la Compañía: los Ejercicios espirituales, la cuarta parte de las Constituciones de la Compañía de Jesús y la Ratio Studiorum. El padre José del Rey Fajardo rescata en este libro la bondad estratégica del método humanista jesuita, en medio de aquel debate que se presentó entre las aspiraciones de los particularismos y las exigencias de los poderes nacionales. Los jesuitas captaron rápidamente esta ruptura y así, como su autor lo menciona, “los ignacianos adquirieron un compromiso con la cultura, la urbanidad, la civilidad, la conversación y con el diseño de un hombre honesto”.
Does he ever sleep? Contributions to science and scientific administration
Authors: Leek Marjorie R.
Published: December 2020

Bill Yost's contributions to organizations, institutions, and academic endeavors are myriad. Let us begin with his participation in the Acoustical Society of America—clearly the academic and professional home for most of us in this room. He has served this society in leadership roles for nearly fifty years, including stints as President and other positions in the ASA administration. His honors from the ASA are the most significant we offer – winning the Silver Medal for Psychological and Physiological Acoustics in 2006 and the Gold Medal in 2018. His contributions include hundreds of articles and books published in JASA and elsewhere, and he is an active participant in the national meetings of the Society. His academic career also includes important leadership roles in academic administrations at two major universities, serving, among other roles, as Dean, Research Administrator, and Department Chair. And all of this, while teaching courses, and writing and editing scholarly books and journal articles. As a leading auditory scientist, Yost enjoys multiple active collaborations world-wide, and has a compelling history of national grant funding. He is a legend and an aspirational example for his students and colleagues. But when does he sleep?
Metasurface-based sound diffusers for noise barrier applications
Authors: Priyadarshinee Prachee , Lim Kian-Meng , Lee Heow Pueh
Published: December 2020

2-D sound diffusers installed with Helmholtz resonators have been investigated as top-edge noise barrier devices. The aim of this work was to study the effect of incorporating metasurfaces in sound diffusers on the broadband performance of noise barriers. This device can be exploited to use the astounding reflection and scattering properties of resonant metasurfaces and sound diffusers to achieve improvement in insertion loss. A three-dimensional indirect boundary element study was conducted to show promising improvement in noise barrier performance.
Scattering coefficients and calculation of acoustic fields in metamaterials
Authors: Dmitriev Konstantin , Rumyantseva Olga
Published: December 2020

An acoustic field in a metamaterial can be represented as the sum of an incident field and all fields scattered by metamaterial elements. Complex scattering coefficients are introduced to describe these scattered fields. The scattering coefficients satisfy the general relationships between their phase and amplitude. Set of their values on the complex plane is the circle with the center of -2i and the radius of 2 in the absence of absorption, or the inner part of this circle, if absorption exists. The use of the scattering coefficients makes it possible to take into account the processes of the multiple scattering between separate elements of the metamaterial, rather than between every two points of the medium, which is typical for traditional scattering problems. This fact simplifies calculation of the acoustic field for a wide class of metamaterials. The limited set of the possible values of the scattering coefficients allows to consider solution of the inverse problem, i.e., to determine a design of a metamaterial element on base of the known scattering coefficients. However, the solution of this problem is unstable in a number of cases. [This study was supported by a grant from the Russian Science Foundation (Project No. 19-12-00098).]
Digital enhancement of speech perception in noisy environments
Authors: Vary Peter , Niermann Markus
Published: December 2020

If speech is reproduced in an acoustically disturbed environment via a loudspeaker, the perception in terms of intelligibility or listening effort may be impaired. Typical situations arise in connection with mobile phones or public address systems. The location of the listener is called the near-end while the speech signal is received from the far-end. Usually, the acoustical background noise cannot be influenced, but speech perception may be enhanced by digital pre-processing of the loudspeaker signal. This pre-processing technique is called Near-End Listening Enhancement (NELE). The received signal is filtered adaptively, by taking the instantaneous characteristics of the background noise into account and by exploiting psychoacoustic properties of the auditory system such as the masking threshold. The increase of the loudspeaker volume is often not allowed or very limited, to avoid injury of hearing or damages of the loudspeaker and because of the listening comfort. In this contribution, state-of-the-art NELE algorithms operating in the short-term frequency domain are reviewed and novel time domain approaches are presented. Furthermore, the differing NELE constraints of public address systems and mobile phones are discussed.
Perturbing sound speed field estimates to study quality of acoustic ranging
Authors: Sarma Ashwin , Andrew Rex , Edelson Geoffrey , Waterston John
Published: December 2020

Acoustic ranging is clearly dependent on the sound speed field c(x,y,z), where the points (x,y,z) are constrained to the two-dimensional region defined by a submerged source at a certain point in the ocean and a submerged receiver at a different but unknown point in the ocean. An in-situ estimate of c(x,y,z) based solely on a sound speed profile taken at the source of known location and one taken at the receiver at a unknown location has been used to obtain reasonable ranging estimates over large source-receiver separation [Sarma etal., IEEE UASP (2019)]. We discuss an approach to perturb this estimate of c(x,y,z) in a physically sound manner consistent with internal wave and other ocean processes in order to study the effect on the accuracy of ranging methods. The approach can indeed be applied to any estimate of c(x,y,z). The ultimate motivation for this work is in-situ determination of the inherent variability expected for a specific range estimate from any range estimation technique.
Automated two-dimensional localization of underwater acoustic transient impulses using vector sensor image processing
Authors: Thode Aaron M. , Conrad Alexander , Reeves Ozanich Emma , King Rylan , Freeman Simon E. , Freeman Lauren A. , Zgliczynski Brian , Gerstoft Peter , Kim Katherine
Published: December 2020

An algorithm is presented for automatically localizing transient impulsive sounds collected on several autonomous underwater vector sensors, spaced 15 to 23 m apart. The procedure, which does not require precise time synchronization, exploits transient signals of interest arriving from different azimuthal directions on each sensor. For each sensor the method first constructs time-frequency representations of both the squared acoustic pressure (spectrogram) and dominant directionality of the active intensity (azigram). Within each azigram sets of time-frequency cells associated with transient energy arriving from a consistent azimuthal sector are identified. Standard image processing techniques then link sets that share similar duration and bandwidth between different sensors, after which the algorithm triangulates the source location using the azimuths associated with the detection set. Data collected from shallow coral reef environments demonstrate the algorithm's ability to detect SCUBA bubble plumes and humpback whale song, and reveal consistent spatial distributions of somniferous fish activity. Analytical estimates and direct evaluations both yield false transient localization rates of 3%–6% in the coral reef environment. Many localized pulses have low signal-to-noise ratios, whose distribution has a median of 7.7 dB and an IQR of 7.1 dB. [Work sponsored by DARPA PALS.]
Low frequency synthetic aperture sonar: Spatial coherence analyse
Authors: Novella Fabien , Pailhas Yan , Le Chenadec Gilles , Quidu Isabelle
Published: December 2020

Spatial coherence is a widely studied notion for HF SAS. It allows the estimation of the navigation of the platform with an accuracy well below the wavelength of the system . It also allows, for high-frequency SAS images, the detection of stable reflectors generally symptomatic of manufactured objects. The theoretical background of spatial coherence is based on a derivation of the Van Cittert Zernike (VCZ) optics theorem adapted to acoustic. However, this theorem uses some assumptions (narrow band signals, Fresnel approximation, Born approximation and homogeneity of the scattering media) that are not necessary met for low frequency system. In this paper effects of wideband systems and presence of a target in the insonified volume are investigated. Do to so, the study is based on a simulation tool whose results are compared with real data from trials conducted by CMRE with a wideband LFSAS. Thanks to the use of a 2-D array, the two dimensional coherence can be analyzed. A sub-band study enables to respect the narrowband VCZ assumption. A statistical study on distribution of degree of coherence estimates allows to point out the presence of strong scatterers symptomatic of manufactured objects.
What did Colonel Fabyan's acoustic anti-gravity device sound like?
Authors: Mooney Jon W.
Published: December 2020

Somewhere within the Geneva (Illinois) Museum of History, next to an old movie theater popcorn machine and closed up behind a false wall, is hidden one of the last surviving components of Colonel Fabyan's acoustic anti-gravity device. Originally built by textile magnate, George Fabyan under the guidance of pseudo-science practitioners, it is Professor Wallace Sabine's examination and quick debunking of the device's anti-gravity powers that is credited with the redirection of Colonel Fabyan's fortune to the creation of Riverbank Acoustical Laboratories and the legitimate scientific study of acoustics. Although the levitation device is not currently on display, the museum's Curator of Collections & Exhibitions gave a small group of acousticians the unique opportunity in 2019 to examine the device's existing components and supporting archival files. Although no one in the group was interested in the device's flying capabilities, everyone was curious what the device must have sounded like during Sabine's testing. Reviewing newspaper accounts of the period, taking photographic measurements of the existing components, using physical and computer modeling, acoustic testing and simulation; we present animation and auralization of Colonel Fabyan's acoustic anti-gravity device in the lab and in-flight.
Peter Narins impact on non-amphibian animal bioacoustics
Authors: Popper Arthur N. , Dooling Robert J. , Fay Richard
Published: December 2020

Combined, we have known Peter Narins for well over 120 years. We take great pleasure in honoring an “old” and greatly valued colleague and friend. We start by pointing out that none of us have done research with Peter, but that each off us knows, admires, and greatly values his work. For over 40 years, Peter's interdisciplinary blend of acoustics, psychophysics, physiology, and anatomy, often conducted in exotic places, has held us all in awe. Moreover, one of the most important part of Peter's work is that its impact extends far beyond amphibians. His work has helped us think about the bioacoustics of birds and fishes, and about the evolution of vertebrate hearing. His work has also stimulated research questions and how we understand research results for non-amphibian species. And, most importantly, it is not only the three of us who have benefitted from Peter's work – his contributions permeate all of animal bioacoustics and will do so for decades. Our talk will focus on how Peter's work has, and continues, to contribute to our own research, and that of many others. [Funded by three old guys.]
High-frequency quantitative ultrasound for characterizing collagen fiber alignment in murine tendon using angular dependence of integrated backscatter
Authors: Wayson Sarah E. , Helguera María , Hocking Denise C. , Dalecki Diane
Published: December 2020

Two major complications following tendon surgery are adhesion formation and re-rupture. There is a need to develop an ultrasound imaging system for non-invasive, non-destructive, longitudinal monitoring of tendon structure throughout a rehabilitation protocol to optimize restoration of range of motion and mechanical properties. Type I collagen is the primary extracellular matrix protein in tendon, and its organization impacts tendon function. The objective of the present study is to develop a high-frequency quantitative ultrasound spectral analysis technique to characterize collagen fiber alignment in murine tendon. This work tests the hypothesis that the integrated backscatter coefficient (IBC) will exhibit anisotropy in murine tendon with aligned structure, and isotropy in murine liver with inhomogeneous structure. Backscattered echoes from murine tail tendon and liver were acquired at varying insonification angles using 38-MHz and 55-MHz single-element transducers. B-mode and IBC parametric images were computed, and the average IBC value in a region of interest was determined at each insonification angle. The IBC was angular-dependent in tendon and isotropic in liver. These data suggest that the IBC can be used to detect collagen fiber alignment in murine tendon, and contribute to establishing the foundation for a dedicated device to non-invasively monitor collagen remodeling during tendon healing.
Optimal valve slide length for brass instruments
Authors: Young Frederick J.
Published: December 2020

One of the first patents for compensating valve brass instruments by US Letters Patent #457,337 dated 11 August 1891 of Fontaine Besson is studied and optimized to obtain a much better in tune compensating instrument. The variance of intonation for the Besson instrument is 18.86%. An optimized four valve brass instruments is devised that lowers the variance to 4.22%. However, the first valve is flat by 7.39% on both sides of the instrument. Because intonation errors of ±5% are tolerable a spring loaded trigger must be provided to shorten the first valve when used alone. An EXCEL spreadsheet is presented analyzing many different three, four and five valve compensating and noncompensating instruments. Of particular interest is a five valve compensating instrument having a variance of 2.37% and standard deviation of 2.48%. The fifth valve lowers the instrument by 6 semitones. Instead of the fifth valve aforementioned a fifth valve of 0.237 of the length of the fourth valve could be used in combination with the fourth valve making the horn lighter. An Excel spread sheet is presented for the calculations relating to many ordinary and compensating three, four and five valve instruments.
Reconciling laboratory and real-world hearing protector testing: The method A versus method B debate
Authors: Gauger Dan
Published: December 2020

A major area of exploration during Elliott Berger's tenure as chair of ANSI S12 working group 11 was the effort to harmonize laboratory testing of hearing protectors with typical performance in real-world use. S12.6-1997 introduced two variants of the Real-Ear Attenuation (REAT) method with different requirements for subject selection and guidance—Method A (experimenter-supervised fit) and Method B (subject fit). Under Elliott's leadership the working group also produced three papers documenting the motivation for these methods. This paper will summarize these papers then focus on what followed: work spanning 2003 to 2010 that explored the strengths and weaknesses of the two methods, as well as how to distill REAT data to ratings that best convey to an industrial hygienist, in a simple fashion, how much performance to expect from a hearing protector. This work, done in an effort to guide potential improvements to the Noise Reduction Rating by the Environmental Protection Agency, led to three new standards: S12.6-2008, S12.68-2009, and S12.42-2010 as well as a comprehensive paper the author produced with Elliott. This work exemplifies Elliott's incessant and, at times, exhaustively thorough quest for clarity and correctness in the standards process.
The journey to hearing protection fit-testing: from a doctoral project, to meeting a mentor, to a world recognized best practice
Authors: Voix Jeremie
Published: December 2020

Introduced in the mid-1970s, the concept of hearing protection device (HPD) fit-testing had been used by several researchers to assess on an individual wearer the exact amount of attenuation provided by a given HPD. In 2000, however, as part of his doctoral work, the author developed an objective method, referred to as Field-MIRE, involving simultaneous measurement with two microphones and dedicated to a new type of instantly molded custom earplugs. The so-called SonoPass measurement system was commercialized by Sonomax and first introduced during the NHCA conference held in Arizona in 2001. This was also for the author the opportunity to first meet Elliott H. Berger, one of his most cited author and soon to become mentor. Their formal collaboration started in 2006 when the F-MIRE system was adapted to test non-custom HPD, became exclusive to AEARO company, and was globally introduced as E-A-Rfit Validation System. Then years of further collaborative work led to ANSI S12.71 standard adopted in 2018 for field attenuation estimation systems (FAES). Along the way, their joint writing for the Noise Manual handbook was remembered by one as “one of the most daunting training job” and by the other as “a truly fun and amazingly rigorous exercise.”
Use of Type II sequence diffusers for the purpose of improving noise barrier effectiveness
Authors: Priyadarshinee Prachee , Lim Kian-Meng , Lee Heow Pueh
Published: December 2020

The Type II Luke sequence diffusers have been known to redirect sound energy and act as a beam steerer at certain frequencies. If the incident sound from the top-edge of a noise barrier can be redirected away from the shadow zone by installing such a device, the insertion loss of the noise barrier can be significantly improved. Numerical analysis revealed that the use of multiple periods of Luke sequence diffusers as reflection phase gratings has potential to improve nose barrier effectiveness even more than using a single diffuser on the top-edge. Compared to a rigid T-barrier, improvement in overall A-weighted insertion loss of 8dBA was achieved by installing sound diffusers designed on the Type II luke sequence on the top-edge of the noise barrier.
An isolation case study of a vertical caisson wall directly adjacent to an underground rail vibration source
Authors: Byrick Wilson
Published: December 2020

A large concrete tower planned for construction was proposed at a site immediately adjacent to underground rail. The underground rail passenger trains pass frequently at a rate of once per 2-4 min 18–20 h per day. Excavation began and a caisson wall was constructed facing the underground vibration source. Preliminary measurements were made by placing an accelerometer on the East facing caisson wall. Attenuation was required in the 20-63 Hz frequency range. An isolation layer (GenieMat DM) was added to the caisson wall. The presentation will illustrate how this was done in combination with water proofing of the foundation and other onsite complexities. Large steel tie-backs are used to hold the caisson wall in place and these were treated to prevent any direct path for vibration. Upon completion of construction, measurements are taken and the level differences are presented. Attenuation exceeded the design and building code criteria at all one-third octave bands of concern.
Acoustic measurements of capillary-gravity water surface waves
Authors: Lirette Robert L. , Zou Zheguang , Liu Guoqin , Gong Xinyue , Zhang Likun
Published: December 2020

For this work an optical method for measuring surface acoustic waves was adapted to acoustics using airborne ultrasound for measurements on water surface waves. With ultrasound incident on periodic traveling water surface waves, the reflected signal can be treated as the diffraction pattern from a moving corrugated reflection grating as long as the amplitude of the water surface waves is much less than the incident acoustic wavelength. The acoustic signal received at the first-order diffraction maxima is amplitude modulated at the frequency of the water surface wave. The intensity of this modulation is directly proportional to the amplitude of the water surface wave. Using spectral decomposition of the signal, the water surface wave amplitudes are precisely determined at sum and difference frequencies around the source peak. The transmission of water surface waves incident on a solid piercing boundary was measured using this method to understand capillary-gravity wave interactions with boundaries. [Work supported by NASA.]
Geometric-acoustics analysis of single-scattering of nonlinearly evolving waves by circular cylinders
Authors: Muhlestein Michael B. , Hart Carl R.
Published: December 2020

Geometric acoustics, or acoustic ray theory, is used to analyze the scattering of high-amplitude acoustic waves incident upon rigid circular cylinders. Theoretical predictions of the importance of incorporating nonlinearity in modeling and the nonlinear evolution of the scattered wave field are provided. An analysis of scattering by many cylinders with a dilute concentration is also provided. The nonlinear evolution of the incident wave is shown to be of much greater importance to the overall evolution than the nonlinear evolution of the individual scattered waves. This presentation is based on an article recently published by the Journal of the Acoustical Society of America.
Derivation of an effective equation for ultrasound propagation in a liquid containing many encapsulated bubbles
Authors: Kikuchi Yusei , Kanagawa Tetsuya
Published: December 2020

Toward an establishment of basis for medical applications such as ultrasound diagnosis, the mathematical model for the propagation of ultrasound (or pressure waves) in a liquid containing microbubbles encapsulated by a viscoelastic shell is constructed from the theoretical viewpoint. For simplicity, the bubbles do not coalesce, break up, appear, and disappear; the bubbles are spherical, and these oscillations are spherically symmetric; the viscosity of gas inside the bubbles and the thermal conductivities of both phases are neglected: these assumptions are the same as those in our previous studies [e.g., Kanagawa et al., J. Fluid Sci. Technol. (2010); Kanagawa, J. Acoust. Soc. Am. (2015)]. In this paper, the Hoff model (equation of spherical shell bubble) is used for the equation of motion of the bubble in order to theoretically clarify the effect of viscosity and stiffness of the shell, instead of the Rayleigh-Plesset or Keller model. From the method of multiple scales, some linear and /or nonlinear wave equations (e.g., KdV-Burgers equation) as an effective equation are derived from the basic set of governing equations for liquids containing many encapsulated bubbles.
The Yost approach to pitch perception: What we can learn from noise-like stimuli
Authors: Shofner William P.
Published: December 2020

One of Bill's major contributions to psychoacoustics is his innovative work using rippled noise (RN) to understand pitch. Bill has argued that RN-pitch percepts can be accounted for by models based on autocorrelation. Working with Bill, we showed that behavioral responses obtained from chinchillas to RNs generally paralleled those obtained from humans, suggesting the underlying processing is similar between the two species. Recent work from my lab using noise-vocoded harmonic tone complexes (NV-HTCs) was inspired by Bill's approach with RNs. NV-HTCs can also evoke pitch percepts like RNs, but present a challenge to Bill's autocorrelation approach, because they can have strong harmonic structures with weak or no periodicities. However, when NV-HTCs are passed through a gammatone filterbank model, weak stimulus periodicities become augmented in summary correlograms. An analytical model based on summary correlograms for NV-HTC responses from (1) humans in a magnitude estimation task and (2) chinchillas in a stimulus generalization task suggests that the underlying processing does indeed differ between the two species. Specifically, chinchillas appear to process the envelope whereas humans appear to process the fine structure. This talk will explore why this apparent processing difference exists, despite the similarity in chinchilla and human auditory filter bandwidths.
Modeling the advantage of head-movements in judging elevation
Authors: Braasch Jonas , Blauert Jens , Pastore M. Torben , Zhou Yi
Published: December 2020

Estimating the elevation of sound sources is a challenging task for the auditory system due to the lack of interaural cues. In the 1930s, Wallach developed the first comprehensive theory on auditory elevation perception by means of auditory motion parallax during head movements. Years later, Blauert found that stationary listeners' perceived localization of narrowband sound sources correlated with the center frequencies of the narrowband sound sources rather than with their actual locations, leading to the idea of directional bands. Returning to Wallach's original idea, which has been modeled also by Zhong, Sun, and Yost in a robot hearing context, a new binaural algorithm will be presented to estimate elevation by auditory motion parallax. The model uses a front end with gammatone filterbanks and cross-correlators to compute binaural activity maps as a function of azimuth, elevation, and frequency. By continuously compensating for head rotations in the horizontal plane, all but the actual sound source position wash out, removing ambiguous positions from the cone of confusion. We will simulate binaural data in two primate species with vast differences in head size—humans and marmosets—to evaluate the generality of using the strategy of auditory motion parallax in elevation localization. [Work supported by NSF BCS-1539276, BCS-1539376, NIH F32 5F32DC017676 & ERC #618075.]
The relationship between segment differentiation strategies and articulatory-acoustic variability across speakers
Authors: Harper Sarah
Published: December 2020

Although variability is prevalent in speech production, individual articulatory and acoustic dimensions differ in their propensity towards variation for any given segment (e.g., Hillenbrand et al., 1995; Whalen et al., 2018). Proposals tying these differences in variability to a dimension's involvement in phonological contrast (e.g., Keating, 1990) are complicated by the observation of interspeaker differences in both the amount of variability exhibited along certain dimensions (e.g., Harper & Goldstein, 2019) and these dimensions' use in segment differentiation (e.g., Schertz et al., 2015). This study examines whether individual differences in the amount of variability exhibited along specific articulatory and acoustic dimensions are related to interspeaker variation in the contribution of these dimensions to differentiating segment pairs. Articulatory and acoustic data from America English speakers in the Wisconsin X-Ray Microbeam Corpus (Westbury, 1994) were analyzed to characterize both the variability of specific dimensions in /s/, /∫/, /l/, and // and the contribution of each dimension to the production of the /s/∼/∫/ and /l/∼// contrasts for individual speakers. Preliminary results suggest co-variation on the level of the individual between the extent of variability observed along particular dimensions and dimensions' contribution to differentiating the examined segment pairs. [Work supported by NIH].
Dysarthria subgroups in talkers with Huntington's disease: Free classification versus feature-constrained classification
Authors: Kim Daniel , Diehl Sarah , de Riesthal Michael , Claassen Daniel , Mefferd Antje
Published: December 2020

In our recent study (Diehl et al., 2019), we examined the perceptual speech features of 48 talkers with Huntington's disease (HD) using the classic feature-based dysarthria rating scale (Darley et al., 1969). A cluster analysis based on speech feature ratings revealed four dysarthria subgroups within our cohort of talkers with HD. Talkers within each subgroup shared deviant speech features that set them apart from talkers with HD in other subgroups. Presumably, talkers with similar patterns of deviant speech features sound alike. In the current study, we will test this notion using a free classification approach. Specifically, 20 naïve listeners will be asked to sort the speech samples of 48 talkers with HD that were used in the previous study into similar-sounding groups. Each listener's grouping decision will be submitted to an additive similarity tree cluster analysis to determine dysarthria subgroups based on the free classification task. Moreover, subgroup-specific speech features will be determined based on the previously established perceptual ratings of the classic dysarthria rating scale. Study outcomes will provide insights into the saliency of specific perceptual speech features in talkers with HD.
Does asymmetry in tongue anatomy affect asymmetry in tongue position? Glossectomy and control subjects
Authors: Stone Maureen , AlSaty Ghaddy , Honig Lisa C. , Lubek Joshua , Zhuo Jiachen , Prince Jerry L.
Published: December 2020

Glossectomy surgery removes part of the tongue due to cancer. The resulting anatomical asymmetries may affect motor symmetry. This study examines anatomical and positional tongue asymmetry in glossectomies and controls. The goals are to determine the extent of the anatomical asymmetries, and their effect on resting asymmetry. We expect that patients with unilateral resections will be more asymmetrical than controls, but that their midline tongue will be centered in the oral cavity (OC), because their dentition is unchanged and the tongue will rest in its familiar position. 3-D tongue volumes were extracted from high-resolution MRI data using Matlab. Tongue volumes were calculated for the whole tongue, both halves and the septum using ITK-SNAP. We bisected the OC in the sagittal plane from the mandibular symphysis to the center of the spinal cord. The tongue volume was calculated in each half of the OC. Results showed more anatomical asymmetry in the patients; seven patients and three controls had a volume difference of 3% or more between the left and right tongue. Positional measures showed that the septum was mostly in one half of the OC. When the septum volume was removed, the tongue volume distributed fairly equally in the OC.
Acoustic correlates of laryngeal control: Parkinson's and healthy older adults
Authors: Vieira Marcelo S. , Auclair-Ouellet Noémie , Clayards Meghan
Published: December 2020

Vocal fold tension is commonly used to control pulmonary airflow and subglottal pressure, resulting in a positive f0-intensity correlation. Since Parkinson's disease (PD) constrains fine movements, this mechanism may be impaired in PD. We analyzed the f0-intensity correlation in PD and a healthy age- and gender-matched control group. For that, we extracted gender-normalized f0, intensity, and spectral emphasis (SE) from each syllable in three sentences of a read text. Additionally, from a sustained [a] task, we measured maximum phonation time ([a] duration; MPT) as well as jitter and shimmer (combined using PCA; JS). Using Linear Mixed Models, we confirmed the f0-intensity correlation in each group. Furthermore, JS interacted with intensity, indicating that voice instability weakens the correlation. No MPT effect was found. Importantly, even controlling for JS and MPT, the f0-intensity correlation was significantly weaker in PD. Lastly, we build a model using SE instead of intensity and only a negative correlation was found. Overall, this study suggests that voice instability negatively affects airflow control, but is not sufficient to explain its reduction in PD. Moreover, it indicates that the SE-f0 relationship is preserved in PD and it is not affected by the voice parameters analyzed.
An acoustic study of plosives production in Cantonese speakers with Parkinson's disease
Authors: Chen Yiting , Wong Min Ney , CHOW Crystal Tze Ying , Wang Xuan , Lin Yuhan , Ng Manwa L. , Pang Shirley Yin Yu
Published: December 2020

Articulatory impairment, including consonant imprecision, has been widely studied in patients with Parkinson's disease (PD). However, acoustic investigation of articulatory impairment in Cantonese speakers with PD has been limited. The purpose of this study was to investigate the acoustic characteristics of plosives production in Cantonese speakers with PD. The participants comprised 17 Cantonese speakers with PD and 17 age- and gender-matched healthy controls (HC). Six Cantonese plosives /p, ph, t, th, k, kh/ followed by the vowel /a/ were produced at high-level tone (T1) in the context of word and sentence. All speech samples produced by PD patients were further divided into two subgroups: normal plosive production (PD-NP) and spirantized plosive production (PD-SP). Higher intensity ratio, shorter VOT and shorter closure duration during plosive production were found in both PD-NP and PD-SP subgroups when compared to the HC group. In addition, aspiration and context did affect the intensity ratio, VOT and closure duration while place of articulation only affected the VOT. Furthermore, it was found that the most commonly misarticulated plosives in Cantonese speakers with PD were bilabial stops, followed by alveolar and velar stops. This finding of spirantization of plosives is in agreement with previous studies.
General formulation of source localization for multiple receivers with fully saturated scattered signals
Authors: Wilson D. Keith , Pettit Chris L. , Ostashev Vladimir , Kamrath Matthew J.
Published: December 2020

A general formulation is provided for the problem of localizing a source from signals at multiple, arbitrarily separated receivers. The signals are assumed to be narrowband and fully saturated by scattering from homogeneous turbulence as they propagate along line-of-sight paths to the receivers. In this case, the complex Wishart distribution can be used to describe the joint distribution of the received signals. Previously derived results from the theory of wave propagation in random media can furthermore be used to model the covariance matrix between the received signals. Then, given a prior distribution on the source location, Bayes's theorem enables the maximum a posteriori (MAP) estimate for the source location to be formulated. This general approach incorporates source localization by beamforming and by signal amplitude as special cases. The behavior of the solution is illustrated with numerical examples.