bluuebunny/crossref_metadata_2025 huggingface dataset:
Epicardial approach for cardiac electrophysiology procedures
Authors: Aryana Arash , d'Avila André
Published: November 2019

Since its introduction over two decades ago, percutaneous epicardial procedures have become well‐adopted by cardiac electrophysiologists, most commonly for catheter ablation of cardiac arrhythmias as well as left atrial appendage closure. The percutaneous epicardial approach has also been utilized for cardiac pacing and drug delivery. But still, its most common usage is for the treatment of intramural and subepicardial substrates that give rise to ventricular tachycardia, particularly in patients with nonischemic cardiomyopathy. In fact, subxiphoid, percutaneous epicardial mapping and ablation have emerged as an important adjunct and in some cases the preferred strategy for characterizing and treating certain types of ventricular arrhythmias. Herein, we will review the indications and rationale for various epicardial procedures. Additionally, we will explore the anatomy of the pericardium as well as the frequently‐used epicardial access techniques. We will further examine the optimal approaches and methodologies for epicardial mapping and ablation and the impact of epicardial fat. We will also discuss the epicardial technique for left atrial appendage closure for the purpose of embolic stroke risk reduction. Finally, we will consider the potential for various complications in the setting of epicardial procedures along with their risk factors and discuss strategies to mitigate such adverse events.
Editorial: Are computers going to take over: implications of machine learning and computational psychiatry for trainees and practising clinicians
Authors: Stringaris Argyris
Published: November 2019

Are computers going to take over? In some ways they already have, and they are bound to take over more. As clinicians and researchers, what do we need to do in order to handle, trust, and evaluate intelligent machines?
Experimental evaluation of the potential for crayfish plague transmission through the digestive system of warm‐blooded predators
Authors: Svoboda Jiří , Fischer David , Kozubíková‐Balcarová Eva , Šťástková Andrea , Brůčková Marie , Kouba Antonín , Petrusek Adam
Published: November 2019

The crayfish plague pathogen (Aphanomyces astaci) can be transmitted through the digestive system of fish, but its dispersal through mammalian and bird digestive tracts has been considered unlikely, and direct experimental evidence remains scarce. We present a small‐scale transmission experiment with European otter and American mink fed with infected crayfish, and experiments testing survival of cultures of five A. astaci strains at temperatures corresponding to those inside mammal and bird bodies. The pathogen was neither isolated from predator excrements nor transmitted to susceptible crayfish exposed to excrements. In agar‐based artificial media, it occasionally survived for 15 min at 40.5°C and for 45 min at 37.5°C, but not so when incubated at those temperatures for 45 min and 75 min, respectively. The five tested strains differed in resistance to high temperatures, two (of genotype groups E and D) being more susceptible than other three (of groups A, B and D). Their survival to some extent varied when exposed to the same temperature after several weeks or months, suggesting that some yet‐unknown factors may influence A. astaci resistance to temperature stress. Overall, we support the notion that passage through the digestive tract of warm‐blooded predators makes A. astaci transmission unlikely.
Malignant melanoma of brown bullhead (Ameiurus nebulosus) in Lake Memphremagog, Vermont/Quebec
Authors: Blazer Vicki S. , Shaw Cassidy H. , Smith Cheyenne R. , Emerson Peter , Jones Thomas
Published: November 2019

In 2012, brown bullhead (Ameiurus nebulosus) with large, raised, black growths were first reported from multiple areas within the Vermont portion of Lake Memphremagog. Subsequent surveys conducted from 2014 to 2017 at two sites within the lake indicated a prevalence of 30% in adult brown bullhead 200 mm and above total length. These lesions ranged from slightly raised smooth black areas to large nodular areas on the body surface and fins and within the oral cavity. Microscopically, these lesions were determined to be malignant melanoma with invasion into surrounding hypodermis, skeletal muscle and bone as well as metastases to gill, ovary and intestine. Liver neoplasms were also observed in 8% of the bullhead collected from Lake Memphremagog in 2015. Neither skin nor liver neoplasms were noted in Ticklenaked Pond, a site used for comparison.
Poverty, competition, democracy, and ownership: A general equilibrium model with vertical preferences
Authors: Kahloul Amani , Lahmandi‐Ayed Rim , Lasram Hejer
Published: November 2019

We consider a general equilibrium model where individuals are simultaneously workers, consumers, and shareholders, with two possible market structures: Monopoly and Duopoly, and two extreme ownership structures: egalitarian and concentrated. Considering three standard poverty indicators, the questions are, whether more competition generates more or less poverty for a given ownership structure; and whether a democratic choice between Monopoly and Duopoly leads to the alternative with less poverty. When the ownership is concentrated, we show that Duopoly generates less poverty than Monopoly and the majority votes for the alternative with less poverty. When the ownership is egalitarian, Duopoly may generate more or less poverty and democratic choice alleviates poverty regarding at least one poverty indicator and worsens poverty regarding at least another one, the three poverty indicators never converging. An empirical study on the effect of competition on poverty supports to some extent our theoretical findings.
Accuracy of a flash glucose monitoring system in dogs with diabetic ketoacidosis
Authors: Malerba Eleonora , Cattani Chiara , Del Baldo Francesca , Carotenuto Gaia , Corradini Sara , Golinelli Stefania , Drudi Ignazio , Fracassi Federico
Published: November 2019

Background

A factory‐calibrated flash glucose monitoring system (FGMS; FreeStyle Libre) recently was evaluated in dogs with uncomplicated diabetes mellitus. It is not known if this system is reliable during diabetic ketoacidosis (DKA).

Objectives

To assess the performance of the FGMS in dogs with DKA and to determine the effect of severity of ketosis and acidosis, lactate concentration, body condition score (BCS), and time wearing the sensor on the accuracy of the device.

Animals

Fourteen client‐owned dogs with DKA.

Methods

The interstitial glucose (IG) measurements were compared with blood glucose (BG) measurements obtained using a validated portable glucometer. The influence of changes in metabolic variables (β‐hydroxybutyrate, pH, bicarbonate, and lactate) and the effect of BCS and time wearing on sensor performance were evaluated. Accuracy was determined by fulfillment of ISO15197:2013 criteria.

Results

Metabolic variables, BCS, and time wearing were not associated with the accuracy of the sensor. Good agreement between IG measurements and BG was obtained both before and after DKA resolution (r= .88 andr= .93, respectively). Analytical accuracy was not achieved, whereas clinical accuracy was demonstrated with 100% and 99.6% of results in zones A + B of the Parkes consensus error grid analysis before and after DKA resolution, respectively.

Conclusions and Clinical Importance

Changes in metabolic variables, BCS, and time wearing do not seem to affect agreement between IG and BG. Despite not fulfilling the ISO requirements, the FGMS provides clinically accurate estimates of BG in dogs with DKA.
Autoimmune hepatitis induction can occur in the liver
Authors: Dywicki Janine , Buitrago‐Molina Laura Elisa , Pietrek Julia , Lieber Maren , Broering Ruth , Khera Tanvi , Schlue Jerome , Manns Michael P. , Wedemeyer Heiner , Jaeckel Elmar , Hardtke‐Wolenski Matthias
Published: November 2019

The priming of T cells in the liver is widely accepted. Nonetheless, it is controversial whether immune activation in autoimmune hepatitis (AIH) occurs in the liver or in the spleen. To address this issue, we splenectomized mice and induced experimental murine AIH (emAIH) with an adenovirus (Ad)‐expressing formiminotransferase cyclodeaminase (FTCD). Post‐splenectomy, the experimental mice developed emAIH to a higher extent than the control mice. In addition, splenectomized mice harboured more intrahepatic B cells and a disproportionately small number of regulatory T cells (Tregs) within a reduced T cell population at the site of inflammation. These results imply that the spleen is not the site of AIH induction. In contrast, the spleen seems to have a protective function since the pathological score was more severe in splenectomized animals. These findings have important implications for the aetiology of AIH.
Accretionary mixing of a eucrite impactor and the regolith of the L chondrite parent body
Authors: Hyde Brendt C. , Tait Kimberly T. , Moser Desmond E. , Rumble Douglas , Thompson Michelle S.
Published: November 2019

Northwest Africa (NWA) 869 is the largest sample of chondritic regolith breccia, making it an ideal source for research on accretionary processes and primordial chemical mixing. One such process can be seen in detail through the first identification of a eucrite impactor clast in an L chondrite breccia. The ~7 mm diameter clast has oxygen isotope compositions (Δ17O = −0.240, −0.258‰) and pigeonite and augite compositions typical for eucrites, but with high areal abundance of silica (9.5%) and ilmenite (1.5%). The rim around the clast is a mixture of breccia and igneous phases, the latter due to either impactor‐triggered melting or later metamorphism. The rim has an oxygen isotope composition falling on a mixing line between known eucrite and L chondrite compositions (Δ17O = 0.326‰) and, coincidentally, on the Mars fractionation line. Pyroxene grains from the melt component in the rim have compositions that fall on a mixing line between the average eucrite pyroxene composition and equilibrated L chondrite composition. The margins of chondritic olivine crystal clasts in the rim are enriched in Fe as a result of diffusion from the Fe‐rich melt and suggest cooling on the scale of hours. The textures and chemical mixing observed provide evidence for an unconsolidated L chondrite target material, differing from the current state of NWA 869 material. The heterogeneity of oxygen isotope and chemical signatures at this small length scale serve as a cautionary note when extrapolating from small volumes of materials to deduce planetesimal source characteristics.
Learning from Apps and Objects: The Human Touch
Authors: Eisen Sierra , Lillard Angeline S.
Published: November 2019

In three studies, we examined children's geography learning from a physical puzzle and an app designed to mimic the puzzle. In Study 1, 5‐ and 6‐year‐olds were taught Australia's states by an experimenter using a puzzle or were taught by an app. Children learned significantly more states from instruction with the puzzle than when they used the app independently. When children were allowed to bring home the puzzle or app for 1 week in Study 2, total learning between conditions was comparable. Length and frequency of use were related to learning only for puzzle users. In Study 3, children were taught the geography lesson by an experimenter using the app. Children's learning from this social app condition was equal to the social puzzle condition but higher than the solo app condition of the earlier studies, suggesting that learning from digital devices is most successful when supplemented with in‐person social interaction.
Depression subtypes and obesity in adults: A systematic review and meta‐analysis
Authors: Silva Daniela Alves , Coutinho Evandro da Silva Freire , Ferriani Lara Onofre , Viana Maria Carmen
Published: November 2019

Examining clinical features of depressive episodes may help elucidating the nature of association between depression and obesity, related to specific symptoms such as appetite and weight changes. This meta‐analysis of observational studies evaluated whether subtypes of depression are associated with specific anthropometric profiles in adults. We searched MEDLINE, LILACS, PsycINFO, Scopus, Web of Science databases, and Grey Literature for articles published up to October 2016 that examined depressive subtypes and adiposity measures among adults. The pooled effect size was estimated with random effects models. The PRISMA guidelines were adopted to reporting results, and this review was registered in PROSPERO (CRD42016035685). A total of 22 articles were included in this systematic review, of which eight had data included in the meta‐analysis, assessing 14 757 individuals with depression. Patients with atypical depression presented a 2.55 higher BMI score compared with those with melancholic depression. Subgroup analysis identified a differential distribution of anthropometric measures in studies conducted with Chinese populations. Among the remainder studies, only one reported discrepant results, possibly due to the exclusion of “weight change” in defining subtypes of depression. Atypical depression was significantly associated with elevated BMI compared with melancholic depression, deserving particular attention due to its clinical importance.
Photosystem II antenna complexes CP26 and CP29 are essential for nonphotochemical quenching in Chlamydomonas reinhardtii
Authors: Cazzaniga Stefano , Kim Minjae , Bellamoli Francesco , Jeong Jooyoen , Lee Sangmuk , Perozeni Federico , Pompa Andrea , Jin EonSeon , Ballottari Matteo
Published: November 2019

Photosystems must balance between light harvesting to fuel the photosynthetic process for CO2 fixation and mitigating the risk of photodamage due to absorption of light energy in excess. Eukaryotic photosynthetic organisms evolved an array of pigment‐binding proteins called light harvesting complexes constituting the external antenna system in the photosystems, where both light harvesting and activation of photoprotective mechanisms occur. In this work, the balancing role of CP29 and CP26 photosystem II antenna subunits was investigated in Chlamydomonas reinhardtii using CRISPR‐Cas9 technology to obtain single and double mutants depleted of monomeric antennas. Absence of CP26 and CP29 impaired both photosynthetic efficiency and photoprotection: Excitation energy transfer from external antenna to reaction centre was reduced, and state transitions were completely impaired. Moreover, differently from higher plants, photosystem II monomeric antenna proteins resulted to be essential for photoprotective thermal dissipation of excitation energy by nonphotochemical quenching.
Flattening Hierarchies. SLI as a Window onto the Architecture of Language
Authors: Lorenzo Guillermo , Vares Elena
Published: November 2019

Children with SLI have traditionally been diagnosed as exhibiting core deficits affecting their phonological and morphological performance. These well‐known aspects of SLI, at least, thus appear to refer the syndrome to the Externalization component of the Faculty of Language. If such a conclusion is on the right track, then it could be predicted that Linearization, also an aspect of Externalization according to the Minimalist architecture of the Faculty of Language, should also be a typical locus of affectation in cases of SLI. This paper presents and interprets data regarding comprehension and production phenomena of a population of Spanish‐speaking children with SLI. These data support the aforementioned prediction, thus reinforcing the design specifications that the Minimalist Program attributes to language capacity.
Ex vivo comparison of barbed sutures for pelvic flexure enterotomy in horses
Authors: Sinovich Matthew , Archer Debbie C. , Meunier Natascha V. , Kelly Padraig G.
Published: November 2019

Objective

To evaluate two different barbed sutures for closure of pelvic flexure enterotomies and compare results achieved with two previously described closure techniques.

Study design

Ex vivo.

Sample population

Twenty‐four fresh cadaver adult equine large colons.

Methods

Cadavers were randomly assigned to four closure groups (n = 6 each group): single‐layer absorbable suture, double‐layer absorbable suture, single‐layer unidirectional barbed suture, or single‐layer bidirectional barbed suture. Construction time, luminal reduction (percentage), bursting pressure, and method of failure were measured. Cost, leakage, exposed suture, and general appearance were recorded. Comparisons were performed with one‐way analysis of variance and post hoc Bonferroni test (P < .05).

Results

Double‐layer absorbable closure had the highest bursting pressure (mean = 178.5 mm Hg, SD = 9.79, P < .001) but took more time (P = .001) compared with all other groups. The construction time of both barbed suture closures did not differ from the single‐layer closure (P > .06). Bursting strengths of both unidirectional (mean = 91.6 mm Hg, SD = 5.57) and bidirectional (mean = 87.5 mm Hg, SD = 8.69) barbed sutures were lower (P > .006 for both) than those of both single‐ (mean = 117.6 mm Hg, SD = 11.69) and double‐layer (mean = 178.5 mm Hg, SD = 9.79) closures. Unidirectional barbed suture closure had a reduction in lumen diameter (P = .004) compared with bidirectional and single‐layer closures.

Conclusion

Enterotomy closures with the two different barbed suture patterns were comparable in bursting strength and construction time. However, the barbed suture patterns had lower bursting strength compared with traditional single‐ and double‐layer closures. Unidirectional barbed suture closure also reduced lumen diameter.

Clinical significance

Closure of a large colon enterotomy with barbed suture patterns may be less secure than single‐ and double‐layer suture closure.
MORAL ORTHOSES: A NEW APPROACH TO HUMAN AND MACHINE ETHICS
Authors: Dorobantu Marius , Wilks Yorick
Published: November 2019

Machines are increasingly involved in decisions with ethical implications, which require ethical explanations. Current machine learning algorithms are ethically inscrutable, but not in a way very different from human behavior. This article looks at the role of rationality and reasoning in traditional ethical thought and in artificial intelligence, emphasizing the need for some explainability of actions. It then explores Neil Lawrence's embodiment factor as an insightful way of looking at the differences between human and machine intelligence, connecting it to the theological understanding of embodiment, relationality, and personhood. Finally, it proposes the notion of artificial moral orthoses, which could provide ethical explanations for both artificial and human agents, as a more promising unifying approach to human and machine ethics.
Simultaneous Interpretation of Three-Phase Relative Permeability and Capillary Pressure for a Tight Carbonate Reservoir From Wireline Formation Testing
Authors: Liu Xiangnan , Yang Daoyong
Published: November 2019

In this paper, techniques have been developed to interpret three-phase relative permeability and water–oil capillary pressure simultaneously in a tight carbonate reservoir from numerically simulating wireline formation tester (WFT) measurements. A high-resolution cylindrical near-wellbore model is built based on a set of pressures and flow rates collected by dual packer WFT in a tight carbonate reservoir. The grid quality is validated, the effective thickness of the WFT measurements is examined, and the effectiveness of the techniques is confirmed prior to performing history matching for both the measured pressure drawdown and buildup profiles. Water–oil relative permeability, oil–gas relative permeability, and water–oil capillary pressure are interpreted based on power-law functions and under the assumption of a water-wet reservoir and an oil-wet reservoir, respectively. Subsequently, three-phase relative permeability for the oil phase is determined using the modified Stone II model. Both the relative permeability and the capillary pressure of a water–oil system interpreted under an oil-wet condition match well with the measured relative permeability and capillary pressure of a similar reservoir rock type collected from the literature, while the relative permeability of an oil–gas system and the three-phase relative permeability bear a relatively high uncertainty. Not only is the reservoir determined as oil-wet but also the initial oil saturation is found to impose an impact on the interpreted water relative permeability under an oil-wet condition. Changes in water and oil viscosities and mud filtrate invasion depth affect the range of the movable fluid saturation of the interpreted water–oil relative permeabilities.
Impact of Fluid Substitution on the Performance of an Axial Compressor Blade Cascade Working with Supercritical Carbon Dioxide
Authors: Tello Carlos , Muñoz Alejandro , Sánchez David , Kipouros Timoleon , Savill Mark
Published: November 2019

Recent research on turbomachinery design and analysis for supercritical carbon dioxide (sCO2) power cycles has relied on computational fluid dynamics. This has produced a large number of works whose approach is mostly case-specific, rather than of general application to sCO2 turbomachinery design. As opposed to such approach, this work explores the aerodynamic performance of compressor blade cascades operating on air and supercritical CO2 with the main objective to evaluate the usual aerodynamic parameters of the cascade for variable boundary conditions and geometries, enabling “full” or “partial” similarity. The results present both the global performance of the cascades and certain features of the local flow (trailing edge and wake). The discussion also highlights the mechanical limitations of the analysis (forces exerted on the blades), which is the main restriction for applying similarity laws to extrapolate the experience gained through decades of work on air turbomachinery to the new working fluid. This approach is a step toward the understanding and appropriate formulation of a multi-objective optimization problem for the design of such turbomachinery components where sCO2 is used as the operating fluid. With this objective, the paper aims to identify and analyze what would be expected if a common description of such computational design problems similar to those where air is the working fluid were used.
Broadband measurements of the acoustic target strength of mesopelagic fishes
Authors: Bassett Christopher , Lavery Andone C. , Stanton Timothy K.
Published: November 2019

The mesopelagic zone (∼200–1000 m) is defined by depths where small amounts of sunlight still penetrate but light levels are insufficient to support photosynthetic activity. This region is one of Earth’s largest ecosystems and is home to a diverse community of marine animals. Biomass estimates for mesopelagic regions, based on acoustic measurements, suggest small fishes at these depths may dominate total fish biomass. These estimates, however, are generally made using surface echosounder measurements at 38 kHz. These measurements are subject to numerous confounding factors including unknown species compositions, physiology, target strength distributions as a function of depth, calibration, and low signal-to-noise measurements. To address these challenges, in addition to questions that require non-acoustic technologies, a towed, integrated sensor platform, the Deep-See, was developed to measure the mesopelagic zone at depth (Lavery et al., 2019). This talk focuses on the acoustics package, which includes commercial and custom split-beam channels from 1–500 kHz. System calibrations and target strength spectra are presented for towed depths up to 700 m, where individual targets are still present in relatively high abundance. Target strength measurements as a function of frequency are considered with an emphasis on their relationship to narrowband, surface-based measurements.
Azimuthal, spatial, and temporal variability of acoustic intensity in along-the-shelf direction of Chukchi shelf from June to August 2017
Authors: Badiey Mohsen , Wan Lin , Pecknold Sean , Turgut Altan
Published: November 2019

Spatial, temporal, and azimuthal variability of sound propagation with simultaneously measured oceanography on the Chukchi shelf is reported. Broadband acoustic signals (0.7 to 1.1 kHz) were transmitted from a single sound source placed near the sound channel axis in 150 m water depth and received by two arrays about 32 km away at different angles forming two acoustic tracks. One was along the 120–150 m isobath and the other crossing 120 to 220 m isobath. The angle between the two acoustic paths was 30 deg. Sound emitted from the common source shows different behavior along each acoustic track. Concurrently detailed water column environmental parameters (i.e., salinity and temperature) were measured in the region in both “along” and “cross-shelf” directions. Emergence of a warm water masses during from late June to July caused a variable channel where transmissions showed markedly large intensity variations (∼20 dB). This presentation quantifies data analysis using correlation between acoustics and environmental signals. [Work supported by ONR 322OA.]
Biomimetic lung surfactant nanodrops for acoustic droplet vaporization
Authors: Thomas Alec N. , Lum Jordan S. , Murray Todd W. , Borden Mark
Published: November 2019

Acoustic droplet vaporization (ADV) involves the liquid-to-gas phase conversion of a superheated emulsion droplet by ultrasound to form an echogenic bubble. This technology may be useful for medical ultrasound, as nanodroplets small enough to leak through endothelial fenestrations may be converted to echogenic microbubbles for extravascular ultrasound imaging of inflamed and angiogenic vasculature. Additionally, droplets may be transformed to acoustically pulsating microbubbles to enhance ultrasound-guided drug delivery. However, surfactant coverage on the droplet often fails to stabilize the expanding interface during ADV, resulting in transitory microbubbles with limited utility. Here, we show that interfacial melting and spreading by lung surfactant during surface dilation can be harnessed to increase the echogenicity and stability of post-ADV microbubbles. Lung surfactant, whose composition in the mammalian lung has been honed over millions of years of evolution, has thus proven to be a superior coating material for ADV droplets, and its biomimicry will be an important step toward clinical translation of ADV in ultrasound imaging and therapy.
Developing a new method for analyzing room acoustics based on auralization
Authors: Algargoosh Alaa , Granzow John
Published: November 2019

Room modes are the resonances that result from generating a sound in a room. The sound coloration produced by these modes is often deemed problematic. Research in room acoustics continues to refine our means to control this coloration for reconciling visual and aural variables in architectural design. Alvin Lucier demonstrated the resonant frequencies of a room in his sound art piece “I am sitting in a room” by recording his speech in a space then playing the recording and re-recording it in the same room multiple times until the resonant frequencies of the room became dominant. Inspired by Lucier’s work, this research explores the possibilities that can emerge from replicating the same iterative process within a simulated framework. Accordingly, a room is modeled, an impulse response (IR) is generated and an auralization is created by convolving an anechoic recording with the IR. The output is then used as an input that is convolved again with the same IR. This method is similar to the method used in artificial reverberation to control the feedback loops of PA systems and is expected to advance room acoustic analysis. This paper discusses the benefits and limitations of the proposed method with possible applications.
An interview with Jerry Harvey, inventor of the In-Ear-Monitor ∼ born of Rock Stars!
Authors: Okorn Edward , Harvey Jerry
Published: November 2019

While this is not a traditional academic presentation, it is an informal and open discussion with the inventor of the In-Ear-Monitor (IEM), by an untrained acoustician Jerry Harvey, out of the request to save the hearing of legendary Rock Star Alex Van Halen. In 1995, Harvey began tinkering and looking for components to solve the problem; in Japan, he found tiny electrical components; and in the United States, he found a tiny speaker designed for a pacemaker. He created a tiny in-ear speaker system that connected to a small receiver on Alex's belt via thin cables. The receiver then picked up the wireless signal from Harvey's mixing board. The in-ear monitors had two small speakers to separate output volume into low and high frequencies for bass and treble, and they fit into shells that were impressions of Alex's ears. The IEMs also blocked out ambient noise, and according to Alex Van Halen, “It was like night and day.” Today IEMs are widely used by musicians, audio engineers, audiophiles, and television presenters in order to receive vocal instructions, from a producer that only the presenter hears. The IEM market is expected to reach close to $1 Billion by 2024.
Basic auditory processing deficits in infants at risk for dyslexia during the sensitive period predict future language
Authors: Mittag Maria , Taulu Samu , Larson Eric , Clarke Maggie , Kuhl Patricia K.
Published: November 2019

It is widely agreed that poor reading and spelling performances in individuals with developmental dyslexia underlie problems with processing phonetic units. According to recent child and adult data, such processing deficits likely are the consequence of compromised low-level auditory processing. A possible causal relationship can be explored by testing infants based on their familial risk of dyslexia. Using magnetoencephalography, the study at hand investigates low-level auditory processing in infants at risk for dyslexia across 6 and 12 months of age—a sensitive period in early language development when the auditory system specializes in native phoneme perception. Results showed smaller and shorter neural responses to simple sounds in at-risk infants at 6 than at 12 months, a pattern that was reversed in age-matched typically developing infants. This interaction was significant both when fitting equivalent current dipoles and when using distributed source modeling and localized to left temporal and left frontal brain regions, indicating its potential impact on early language learning. In addition, atypical auditory responses in at-risk infants consistently predicted later language skills, such as syntactic processing and word production, thus identifying a possible biomarker of dyslexia in the infant brain.
The perceptual assimilation and discrimination of 20 Hindi consonants by native speakers of English
Authors: Barrios Shannon L. , Hayes-Harb Rachel
Published: November 2019

Hindi consonant contrasts are known to pose difficulties for native English speakers (e.g., Polka, 1991; Werker and Tees, 2002; and Cibelli, 2015). While a limited set of Hindi consonants have received a great deal of attention (i.e., the coronal stops), we do not yet know how learners perceive other segments from Hindi’s relatively large consonant inventory. To address this gap, we conducted a perceptual assimilation study modeled after Faris et al. (2018) to investigate the perceptual assimilation of twenty Hindi consonants (tʃ, tʃʰ, dʒ, dʒʰ, t̪, t̪ʰ, d̪, d̪ʰ, ʈ, ʈʰ, ɖ, ɖʰ, ʃ, ʂ, s, z, l, r, ɽ, ɽʰ) by native English speakers with no prior Hindi language learning experience. We later examined the discrimination of 46 pairs from the same set of phones in a new group of participants from the same population using an AX discrimination task. Participants exhibited patterns of perceptual assimilation and discrimination of Hindi phonemes that suggest that native English speakers will experience difficulty across the Hindi consonant inventory. We consider the findings in the context of the Perceptual Assimilation Model (Best, 1994 and Best and Tyler, 2007), providing a fuller account of the difficulty posed by the Hindi consonant inventory for second-language learners.
Knowledge of word stress patterns in English in Korean Learners: The case of English trisyllabic nouns
Authors: Kim Sung Yeon , Oh Eunjin
Published: November 2019

This study aims to explore Korean learner knowledge of word stress patterns in English trisyllabic nouns. Building upon the previous findings from Guion (2005), further studies should look at data regarding more syllabically complex words. While the stress placement rules in English require at least three syllables to be applied, the study (Guion, 2005) only observed the individuals’ stress placement patterns in English disyllabic words. The prevalence of longer polysyllabic words in the English language necessitates observation of Korean learner speech patterns in English trisyllabic words. A total of 16 Korean learners of English participated in the experiments that explore the distributional patterns of stress placement based on word type (i.e., nonwords and real words) and syllable stress position on English trisyllabic nouns. Compared to that of native English speakers, Korean learners of English showed significantly higher error rate on stress placement rules in English nouns—particularly higher error rates on production and perception of nonwords, compared to that of English real words. The predictive factors (word type, syllable structure, and syllable weight) had a significant effect on the stress placement on both groups. Based on the results, our goal is to discuss how the learners use their previous language learning experience when they decide on which syllable to apply stress.
Examining vowel nasalization in English word productions of bilingual and monolingual Cajun heritage speakers
Authors: Vidrine Lauren V. , Shport Irina A.
Published: November 2019

One perceived characteristic of Cajun English (CE) spoken in the state of Louisiana is vowel nasalization, which has been attributed to Cajun French (CF) influence and has been reported in oldest generation Cajuns and young generation Cajun men (DuBois and Horvath, 1998, 2000). Previous research involved only CF-CE bilinguals and sociolinguistic coding based on auditory impressions. In this study, acoustic measures were used to investigate vowel nasalization among both CF-CE bilinguals (the oldest generation) and CE monolinguals. Five bilinguals and five monolinguals completed a word-reading task. In 39 monosyllabic words, four vowels occurred in both oral and nasal environments (CVC, CV, CVN). Nasality measures included bandwidth of F1; the difference between F1’s amplitude and the highest of the first or second harmonic (A1-P0); and the difference between F3’s amplitude and P0 (A3-P0). These were identified as most effective to distinguish oral and nasal vowels (Styler, 2017). Results showed that in comparison to monolinguals, vowels produced by bilinguals were more nasalized in both oral and nasal environments. This suggests that the vowel nasalization may be fading in CE, as it is lessened among young monolinguals. The results are discussed in relation to theories regarding cross-linguistic influence in bilingual communities.
Some trends and features in deep-ocean noise determined from the CTBTO hydroacoustc stations
Authors: Robinson Stephen P. , Harris Peter M. , Cheong Sei-Him , Wang Lian , Livina Valerie
Published: November 2019

This paper describes the results of applying s statistical method for long term and seasonal trend analysis and uncertainty evaluation of the data from deep-ocean noise data. The analysis method uses a flexible discrete model that incorporates terms that capture seasonal variations in the data together with a moving-average statistical model to describe the serial correlation of residual deviations, with uncertainties validated using bootstrap resampling.The measured data originate from a number of the hydro-acoustic monitoring stations of the CTBTO and span up to a maximum of 15 years. The analysis focuses on the data from Cape Leeuwin Southern Ocean), Wake Island (Pacific Ocean), Ascension Island (Atlantic Ocean), and Diego Garcia (Indian Ocean). The trend analysis is applied to time series representing monthly and daily aggregated statistical levels for five frequency bands to obtain estimates for the change in sound pressure level with associated coverage intervals. The features of the data are described, including the differences observed in the seasonal variation and the long-term trends, with the latter often exhibiting negative gradients. A tentative discussion is initiated of the potential causes of some of the observed trends and fluctuations.
Global soundscapes: Parabolic equation modeling and the CTBTO observing system
Authors: Heaney Kevin D. , Eller Anthony I.
Published: November 2019

The open ocean is not a quiet place, particularly in the Northern Hemisphere. The soundscape of a local environment is defined as detailed understanding of the noise sources observed in time, frequency and space. In this paper we present a set of models and observations of the open ocean sound field utilizing the long-term observations from the Comprehensive Test Ban Treaty Organization (CTBTO) of the United Nations. This system of axial hydrophones spanning the globe in remote locations provides a treasure chest of data for looking at low frequency sound. For frequencies below 125 Hz, half the CTBTO sample rate, the sound field is dominated by local and distant ships, local wind, marine mammals, seismic surveying and seismic events. A basin wide model, with the Parabolic Equation model for propagation, will be presented using Satellite AIS data, surface wind fields and some estimates of fin whale distributions and seismic surveys. The science questions to be addressed are: Can we observe the wind noise or is shipping to dominant? What mechanisms explain wind noise below 50 Hz? Can we use data to move towards a better model for surface shipping source levels? Can we evaluate Fin Whale distributions from regular recordings?
Doppler ultrasound bandwidth imaging: A new technique for mapping unstable flow
Authors: Yiu Billy Y. , Chee Adrian J. , Tang Guo , Luo Wenbo , Yu Alfred C.
Published: November 2019

Unstable flow plays an important role in the initiation and progression of atherosclerosis. Yet, mapping flow instability in arteries is challenging because such event is dynamic over both space and time. In this work, we present a new framework called Doppler ultrasound bandwidth imaging (DUBI) that makes use of high-frame-rate plane wave excitation and Doppler bandwidth analysis principles to identify unstable flow regions within an image view. DUBI works by performing autoregressive modeling at every pixel position to estimate the instantaneous Doppler bandwidth, which in principle is broadened by the wider range of velocities attributed to the emergence of unstable flow. DUBI’s performance in mapping unstable flow was tested with laminar and turbulent flow conditions in a nozzle-flow phantom. Results showed that DUBI was able to quantify the difference in Doppler bandwidth magnitude (increased from 2.1 to 5.2 kHz) as the flow condition changed from laminar to turbulent. Also, DUBI was found to be able to identify and map the unstable flow region with the image view, outperforming conventional Doppler variance imaging. This observation was substantiated by receiver operating characteristic analysis, in which DUBI achieved a sensitivity of 0.72 and specificity of 0.83 (vs 0.66 and 0.68, respectively, for conventional Doppler variance imaging). We anticipate that DUBI can be applied in vivo to obtain useful information for clinical diagnosis of atherosclerosis.
Mathematical music theory and the representation of Igbo music
Authors: Calilhanna Andrea , Onwubiko Stephen G.
Published: November 2019

The purpose of our paper is to introduce African mathematical music theory: to analyze and represent African (Nigerian) music through visualizations and sonifications of beat-class theory. Many of the current analytical methods to study African (Nigerian) music lack the qualities necessary to recognize the intricate imbibements from music. Western music theory has evolved largely as a result of non-Western influences and beat-class theory provides a viable solution for the lapses in analytical work which have led to the superimposition of Western ideas of Nigerian music. Musical set theory uses the universal language of mathematics to explore the complexity, beauty and cultural significance of Nigerian music. In our paper, we will provide a discussion of meter in Ikpirikpi Ogu, the Ohafia War Dance of Igboland of Nigeria, to explore how Igbo music from Nigeria can be analyzed through the narrative of mathematical music theory using visualizations and sonifications of beat-class theory in circular cyclic graphs and ski-hill graphs to represent and acknowledge the listener’s psychoacoustic experience of music.
Low frequency sounds from entertainment and exercise venues: Methods for prediction, measurement, and annoyance assessment
Authors: Woolworth David S.
Published: November 2019

The advent of inexpensive low frequency reproduction has made the subwoofer loudspeaker ubiquitous and has in turn driven an increase in low frequency content in many forms of popular music. The result is music played in entertainment and exercise venues contains a lot of low frequency information at high sound levels, while prediction for design, ANSI testing standards, and U.S. ordinances do not properly address the full frequency spectrum in question or the pulsing nature of low frequencies. Furthermore the proliferation of lightweight mixed use construction and development of entertainment districts to revitalize urban areas puts these low frequency sources adjacent to or near residences, creating the need for a more comprehensive set of methods for assessment. This paper provides a compiled set of methods and techniques to assess low frequencies from entertainment and fitness venues, drawing on various standards, industrial noise methods, and the author’s experiences and sample data.
Open speech platform: Web-apps for hearing aids research
Authors: Zubatiy Tamara , Bhattacharya Uposhanto , Gan Ziqi , Hamilton Sean , Ganz Chockalingam , Garudadri Harinath
Published: November 2019

Open Speech Platform (OSP) for hearing aids (HA) research comprises a realtimemaster hearing aid (RT-MHA); and an embedded web server (EWS) that serves webpages to any browser enabled device for monitoring and controlling RT-MHA. In this contribution, we present 4 classes of web-apps that can be combined and extended in novel ways to conduct psychophysical investigations beyond what is currently possible. (1) The Researcher apps provide access to all RT-MHA parameters; these settings can be saved in named files and recalled easily. (2) HA Fitting apps are written to capture audiologists’ hypotheses on HA parameters and their interactions in improving performance; conversely, they can incorporate human-in-the-loop research wherein, the user is forced to select one of two HA parameters (say, A and B) used to process specific speech stimuli stored in a database on OSP; the settings A and B are successively refined based on the user’s choice. (3) Ecological Momentary Assessment (EMA) apps are used to capture the user’s state for a given HA settings in a given listening environment. (4) Assessment apps enable various tests (e.g., syllable and word recognition tests) in a repeatable manner using stimuli stored in a database on OSP.
1-D elastic immersive wave experimentation in an aluminum beam
Authors: Thomsen Henrik R. , Moleron Miguel , Haag Thomas , van Manen Dirk-Jan , Robertsson Johan O.
Published: November 2019

In immersive wave experimentation, a physical experimentation domain is immersed in a larger numerical simulation such that waves in the physical domain drive the numerical simulation and vice-versa. For elastic media, the interaction takes place through sources and sensors at the free surface, where the wavefield is measured and the immersive boundary condition (IBC) is computed and applied. We present a theoretical and experimental study on the implementation of 1-D IBCs for elastic waves in an aluminum beam. Utilizing a 3-D Scanning Laser Doppler Vibrometer (LDV), we measure longitudinal and shear components of a wavefield along the beam. The recorded wavefield is then separated into incident and reflected components and converted into traction. By applying the incident wavefield traction as a boundary condition using a three-component piezo-actuator, we can effectively mitigate broadband longitudinal and shear wave reflections from the boundary, provided the piezo-actuator is calibrated to behave as an idealized point force source. Furthermore, we dynamically link the physical experiment with a numerical background model, introducing virtual scattering. Our results enable elastic immersive wave experimentation at lower frequencies closer to those encountered in real-world scenarios.
Rotational invariance in the design of structures with imbedded acoustic black hole vibration absorbers
Authors: Shepherd Micah R. , McCormick Cameron A.
Published: November 2019

The acoustic black hole (ABH) effect, where the wavespeed of a structure is intentionally reduced to near zero by altering its thickness according to a power-law taper, has been utilized on plates and beams to achieve vibration reduction. Several ABH designs have been proposed for uniform beams including the inverted and the double leaf ABH. However, these designs are only applicable for reducing flexural vibration in a single dimension. A rotationally invariant concept is presented where the imbedded ABH is symmetric around the center line of the beam. Various damping configurations are then applied to the rotationally invariant ABH and their respective amounts of vibration reduction are compared. Finally, the challenges of manufacturing such an ABH design will be discussed in the context of three-dimensional printing and additive manufacturing.
Effectiveness of a portable device on dysarthrias in daily life—Verification of the effects with DAF and without DAF
Authors: Shimura Eiji
Published: November 2019

Several methods for rehabilitating speech rate control have been widely used to improve speech intelligibility in patients with mild dysarthria. However, few studies have reported the therapeutic effects of these methods in daily life. Delayed auditory feedback (DAF) is one such speech rate control method. A small, portable DAF device has recently been developed that can be used by patients in their daily life. In this study, three dysarthric patients wearing the portable DAF device underwent a 20-min practice per day for 3 months. During the practice, they were instructed to prolong vowel length while using the device. The improvement in the intelligibility of spontaneous conversation was more in patients wearing the portable DAF device than in those who did not wear the device. The patients mastered the speech method using prolonged vowel length pronunciation with the use of the device continuously over a period of time. This finding suggests that the portable DAF devices can be sustainably used in daily life. Even when the device was not used, patients’ speech rates significantly decreased at the word level after treatment. This finding suggests that the effectiveness of the portable DAF device is carried over after 3 months of its use.