bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructural anisotropy evaluation in trabecular bone structure using the mode-converted (longitudinal to transverse, L-T) ultrasonic scattering
Authors: Yousefian Omid , Du Hualong , Horn Timothy , Muller Marie M.
Published: April 2019

The mode-converted ultrasonic scattering method is utilized to characterize the structural anisotropy of a phantom mimicking trabecular bone, fabricated using metal additive manufacturing from a high resolution CT image of trabecular horse bone. A normal incidence transducer transmits longitudinal waves into the sample, while the scattered transverse signals are received by an oblique incidence transducer. Four L-T measurements are performed by collecting scattering from four directions. The results show that the L-T converted scattering amplitude is highly dependent on the microstructural anisotropy direction. The ratios of L-T converted amplitudes for measurements in different directions is calculated to characterize the anisotropy of sample. The results show that the anisotropy is changing along the sample, which coincides with simulation results previously obtained on the same structures, as well as with the anisotropy estimated using image processing of the CT scans. The anisotropy was shown to increase monotonously along the sample from 0.48 to 0.7 depending on the location. At the same time, the ratio of LT scattering amplitude measured in two perpendicular directions was shown to increase monotonously from 0.6 to 0.67. These results suggest the potential of mode-converted methods to assess the anisotropy of structures including trabecular bone.
Evaluation of bone fracture healing in children using acoustic radiation force: Initial in vivo results
Authors: Ghavami Siavash , Gregory Adriana , Webb Jeremy , Denis Max , Kumar Viksit , Milbrandt Todd A. , Larson A. Noelle , Fatemi Mostafa , Alizad Azra
Published: April 2019

Vibrational characteristics of the bone are directly dependent on bone’s physical properties. In this paper, a vibrational method for bone evaluation is introduced. We propose a new type of quantitative vibro-acoustic method based on acoustic radiation force of ultrasound for bone characterization in patients with fracture. In this method, we excite the clavicle and ulna by an ultrasound radiation force (URF) pulse. The URF pulse induces vibrations in the bone, resulting in an acoustic wave that is measured by a hydrophone placed on the skin. The resulting acoustic signals were used for wave velocity estimation based on cross-correlation technique. To further separate different vibration characteristics, we adopt a variational mode decomposition (VMD) technique to decompose the received signal into an ensemble of band-limited intrinsic mode functions, which allows analyzing the acoustic signals in terms of their constitutive components. We conducted a prospective study that included a total of 15 patients, 12 with clavicle fractures and 3 with ulna fractures. The contralateral intact bones were used as control. Statistical analysis demonstrated that fracture bones can be differentiated from intact bone with a detection probability of 80%. Also, we introduce a “healing factor” that quantifies the progress of healing in clavicle bones. Statistical analysis showed that healing factor can track the progress of healing in clavicle in 80% of fractures.
Ultrasonic bone assessment using backscatter difference measurements at 1 MHz
Authors: Hoffmeister Brent K. , Main Evan N. , Sharp Phoebe C.
Published: April 2019

There is interest in developing ultrasonic techniques that can be used to detect changes in bone caused by osteoporosis. One approach, called the backscatter difference technique, measures the power difference between two portions of a backscatter signal from cancellous bone. Previous laboratory studies have tested the technique using transducers with center frequencies > 2 MHz. The present study uses a 1 MHz transducer which may improve performance at central skeletal sites such as the hip and spine. Measurements were performed in vitro on 54 cube shaped specimens of cancellous bone from 14 human femurs using a broadband, single element 1 MHz transducer. Received backscatter signals were analyzed to determine the normalized mean of the backscatter difference (nMBD) which was computed by measuring the power difference between two gated portions of the backscatter signal in decibels and dividing by the gate separation in microseconds. Linear regression analysis found weak to moderate correlations (0.13 ≦ R ≦ 0.66) between nMBD and bone density, depending on which portions of the signals were analyzed. These results suggest that backscatter difference measurements using a 1 MHz transducer may be able to detect changes in bone caused by osteoporosis.
Standing acoustic waves in microfluidic channels for enhanced intracellular delivery of molecular compounds
Authors: Centner Connor S. , Priddy Mariah C. , Kopechek Jonathan A.
Published: April 2019

Intracellular delivery of molecular compounds is required for many in vitro research applications. Ultrasound-induced cavitation has been shown to enhance intracellular delivery of molecular compounds via mechanisms that may include sonoporation or endocytosis. Recently, acoustofluidic approaches have been developed to utilize standing acoustic waves (SAW) for cell manipulation in microfluidic channels. In this study, the effect of SAW on fluorescein release from perfluorocarbon double emulsion droplets in microfluidic channels was explored. Vaporization of perfluorocarbon double emulsion droplets induced by SAW may potentially enhance intracellular delivery of molecular compounds. In this study, fluorescein-loaded double emulsions were passed through a microfluidic device and exposed to 8-MHz SAW. Fluorescein release was quantified by measuring the change in fluorescence of the supernatant before and after treatment. Treatment with SAW in microfluidic channels increased the fluorescence by 8.8-fold compared to the baseline level. Fluorescein release was also higher after treatment with SAW compared to samples that passed through the microfluidic device without exposure to SAW (p = 0.03). These results suggest that SAW and perfluorocarbon double emulsions in microfluidic channels could potentially enhance the efficiency and consistency of intracellular molecular delivery in vitro.
Therapeutic ultrasound-induced insulin release in vivo
Authors: Singh Tania , Suarez Castellanos Ivan , Chatterjee Bhowmick Diti , Cohen Joshua , Jeremic Aleksandar , Zderic Vesna
Published: April 2019

We have previously shown that therapeutic ultrasound is capable of stimulating insulin release from pancreatic beta cells, non-invasively, safely and effectively. The aim of this work is to conduct preliminary animal studies to evaluate the feasibility of controlled insulin release in vivo using therapeutic ultrasound. Wild type hIAPP + / + white FVB mice were randomly assigned to either the ultrasound treatment group or the sham group. Mice in the ultrasound treatment group received one five-minute treatment of continuous 1 MHz ultrasound at 1 W/cm2 . Blood samples were collected via tail nick immediately prior to ultrasound application and immediately after ultrasound application. The pancreas was excised for histological analysis using H&E staining. No gross damage—including any burns on the skin—in the treatment area were observed and there was no evidence of skin burning or internal damage of the abdominal organs, especially the pancreas, found during necropsy. As measured by ELISA, the experimental group treated with ultrasound exhibited an increase of 0.43 ng/ml in blood insulin concentration compared to a 0.60 ng/ml decrease in the control group after 5 min (p < 0.01). Our preliminary results show promise in the translational potential of therapeutic ultrasound in the treatment of type 2 diabetes. We expect that our approach, with careful selection of ultrasound parameters, may provide a safe, controlled and targeted stimulation of insulin release from the pancreatic beta cells.
Comparison of infrasound emissions observed during a tornado with potential fluid mechanisms
Authors: Petrin Christopher , Elbing Brian R.
Published: April 2019

Infrasound may be emitted by tornado-producing storms up to 2 h before tornadogenesis, and due to their low atmospheric attenuation, these low frequencies may be detected several hundreds of kilometers away. Therefore, passive infrasound monitoring shows potential for the study and prediction of tornadoes, provided received infrasound signals can be correlated with the flow-fields of tornadoes. Literature indicates that tornadoes do cause high infrasound levels between 0.5 Hz and 10 Hz, but the radially vibrating vortex mechanism commonly proposed to explain this production [Abdullah, Mon. Weather Rev. 94, 213–220] has been shown to be non-physical. Schecter [Mon. Weather Rev. 140, 2080–2089] showed these limitations and showed using numerical experiments of a tornado-like vortex produced infrasound from around the storm’s melting level. As this level contains diabatic processes involving hail, it also appears that hail production could be connected to tornado infrasound. In the current work, observations of atmospheric infrasound during a small tornado that occurred on 11 May 2017, will be evaluated in light of these previous studies.
Overview of ongoing infrasound research at the Georgia Institute of Technology
Authors: Medda Alessio , Ahuja Krish , Funk Rob , Alvord David , Dickey Darryl , Dowd Elliot , Trostel John
Published: April 2019

This presentation discusses ongoing research in Infrasound technologies at the Georgia Institute of Technology, Georgia Tech Research Institute (GTRI), the applied research arm of the Georgia Tech. In particular, results of a study that compared a number of commercially available infrasound sensors with several windscreen technologies are presented. Among them, comparisons obtained with a wind screen loaned to GTRI by NASA Langley and described by Ahuja and Shams in the 2017 Infrasound Workshop are also presented. Sources producing controlled infrasound under study at GTRI are also discussed. These include a sonic boom simulator, a propane vapor burner, oscillating jets, a nitrogen cannon and a low frequency acoustic driver. In addition, signatures from people moving through doorways are also presented. Each source was most effective in a given frequency range. Controlled infrasound at 0.1 Hz was obtained by several sources, among which a flame and a cold plume modulated at nominal frequencies of 0.1 Hz. Moreover, preliminary results of successful attempts at characterizing the infrasound sources and removing wind noise via wavelet analysis are also presented.
Effects of perturbing a reference atmosphere on sonic boom propagation and metrics
Authors: Wade Lucas , Sparrow Victor
Published: April 2019

There is substantial interest in the accurate noise prediction that ranges from sonic boom noise from conventional supersonic aircraft to low-boom noise (a sonic thump sound) from future aircraft designed for quiet flight. A carefully designed reference atmosphere was developed for comparing multiple sonic boom propagation programs. In the current work, that reference atmosphere was perturbed in a number of ways to assess the importance of each perturbation. The code PCBoom was used for this study, and the perturbations were for the temperature, humidity, and wind profiles. One result is that in the absence of winds, perturbing the temperature profile does not substantially affect the metrics on the ground, but perturbing the humidity profile does. [Work supported by the U.S. Federal Aviation Administration Office of Environment and Energy through ASCENT, the FAA Center of Excellence for Alternative Jet Fuels and the Environment, Project 41 through FAA Award No. 13-C-AJFE-PSU under the supervision of Sandy Liu. Any opinions, findings, conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the FAA.]
Visual influences on auditory spatial processing
Authors: Zhou Yi
Published: April 2019

Sensory experience is the result of a multisensory analysis of the environment around us. When information is properly integrated, visual cues facilitate auditory localization. To investigate the spatial and temporal rules of contingency in multisensory integration, a majority of previous studies have focused on sensory space within the field of vision. But the spaces encoded by vision and audition do not always align with each other. For foveal species such as humans and monkeys, the visual field is restricted to frontal space, whereas the auditory field is panoramic, covering the entire frontal and rear space. The rear sensitivity provided by spatial hearing is critical for avoiding unseen dangers coming from behind. The rear space, however, has been largely overlooked in multisensory research. In this talk, I will present recent work related to vision’s role in panoramic spatial hearing in humans, the changes in visual bias observed in human listeners with chronic unilateral hearing loss, and findings concerning visual modulation of spatial responses of single neurons in the marmoset auditory cortex. Based on these results, I will discuss the challenges of implementing existing theories of multisensory spatial perception in neural circuits.
Restaurant acoustics—A challenge for consultants
Authors: Genuit Klaus
Published: April 2019

A good restaurant should be a place where you can enjoy food, drinks, and talking with friends. This means besides the quality of the dishes, wines, etc., the acoustical comfort in the restaurant is an important parameter. But how to describe a good acoustical quality of a restaurant, what are the parameters, how to measure, and how to evaluate the situation? Not only is the level an indicator but others like privacy and speech intelligibility are also indicators. As the overall perception and evaluation of the event inside a restaurant is strongly dependent on context besides measurement and analysis, interviews of the involved people are requested like it is recommended within the new ISO TS 12913-2 standard for soundscape. An overview of different factors influencing the restaurant acoustics and methods exploring the sound will be given.
The characteristics of song: An overview for marine mammals
Authors: Hildebrand John
Published: April 2019

Animal song is often considered to have the following characteristics: (1) produced by males, (2) territorial—related to ownership of an area, (3) stereotyped, (4) seasonally produced, and (5) involved in reproductive displays. The extent to which marine mammals fit these criteria is considered for a variety of species. The occurrence of female song and the lack of clear territoriality are examples that challenge the above model for sexual-selection of singers. Likewise, the factors driving long-term trends in song are not well understood. New perspectives are needed to understand the mechanisms driving marine mammal song.
Evidence of synchronous chorusing in North Atlantic minke whales (Balaenoptera acutorostrata
Authors: Stocker Michael A.
Published: April 2019

Many arthropods are known to chorus acoustically. Some families such as the Gryllidae are known to synchronize their chirping, and other families such as the Cicadidae are known to buzz together or pulse in groups. In the Gryllidae, synchronization is facilitated by way of corollary discharge that “blanks” the auditory nerve concurrent to stridulation syllables. This permits the individual animal to “not hear” itself while chirping and to hear nearby conspecifics if they are not in sync. Thus, when animals are synchronized, none of them hear anything, unless one falls or phases out of sync. There are many conjectures as to why they synchronize. It is clear that in doing so, they establish an acoustic community. The larger sound-field also ambiguates the location of individual animals to potential predators. There is some evidence that conspecific communication occurs within the chorus which may convey local conditions (such as the presence of a predator) to the acoustic community. Many rorquals (blue, fin, sei, Brydes, and minke whales) pulse in the low and infrasonic frequency ranges. This paper will present and evaluate recorded evidence which might suggest that minke whales may synchronize their pulsing with others—potentially forming an acoustic community with conspecifics.
A study on the improvement of a brain concentration using acoustic characteristics of sound
Authors: Bae Seonggeon , bae Myungjin
Published: April 2019

It has been studied variously using acoustic features. The purpose of this study is to investigate whether the characteristics of acoustic signals improve the brain concentration. Especially, the phenomenon that occurs in a tedious and repetitive environment is analyzed by using acoustic characteristics of sound. This characteristic was measured by 20 persons in general, and the concentration of brain was compared and analyzed.
High temperature resonance ultrasound spectroscopy studies of single crystal minerals
Authors: Tennakoon Sumudu P. , Mookherjee Mainak
Published: April 2019

Elasticity of mineral phases at temperature and pressure conditions relevant to earth interior is essential for constraining the composition and the dynamics of the deep Earth. To constrain the temperature dependence of elasticity of hydrous minerals relevant to the earth’s subduction zones, we used high temperature Resonance Ultrasound Spectroscopy (RUS). We explored the temperature dependence of the full elastic moduli tensor, speed of sound, attenuation, and anisotropy of naturally occurring single crystal topaz (Al2SiO4F1.42(OH)0.58) [1] with a rectangular parallelepiped geometry. The RUS spectra are influenced by the geometry, density, and the full elastic moduli tensor [2]. We determined the crystal symmetry and crystallographic alignment of the crystals using X-ray diffraction. The geometry and density are well constrained from previous results on thermal expansion. The elasticity results on topaz are in good agreement with previous studies. We combine the high temperature elasticity of natural topaz with the results from the first principles on end member hydrous topaz and shed insight into how pressure temperature and composition, i.e., the fluorine and hydrogen content could influence elasticity of minerals in the Earth’s interior, in particular in subduction zone settings. [Work supported by U.S. NSF Award Nos. EAR-1634422 and EAR-1753125.] References: [1] Tennakoon et al., Sci. Rep., 8, 1372 (2018). [2] A. Migliori and J. D. Maynard, Rev. Sci. Instrum.76, 121301 (2005).
Acoustics-based 3-dimensional temperature gradient determination in paraffin wax
Authors: Pantea Cristian , Greenhall John , Davis Eric S. , Chavez Craig
Published: April 2019

There are currently no technologies to noninvasively assess explosive condition from outside its external confinement for explosive safety activities. Knowledge of the explosive condition inside an item can help to estimate the time that remains before thermal damage ignites the explosive, or how the explosive responds to various actions. Acoustic technologies based on COTS hardware and designed to determine temperature gradients have been in development for several years with no demonstrated success. Conventional acoustical sources at low frequencies tend to have a large beam-spread with side lobes, resulting in significant acoustical energy losses and very poor spatial resolution. The use of a unique collimated low-frequency sound beam and beam scanning, developed recently in our lab, was investigated in paraffin wax for acoustic temperature determination. Acoustic through-transmission experiments, and knowledge of the relationship between sound speed and temperature led to spatially resolved three-dimensional temperature field inside the sample, in good agreement with those measured using thermocouples.
Trade-offs between labial and lingual activity in the Suzhou Chinese labial fricative vowels
Authors: Faytak Matthew , Kuo Jennifer , Wang Shunjie
Published: April 2019

We examine trading relations between lingual and labial activity for three back vowels with different labial constrictions in Suzhou Chinese. Specifically, we compare the labial “fricative vowels” [ɯƜβ] and [ɯƜv], which exhibit a compressed lip opening and a labiodental constriction, respectively, with rounded [u]. Linear mixed-effects modeling of indices of tongue contour shape extracted from ultrasound video demonstrates that the degree of tongue dorsum raising differs systematically from vowel to vowel: [ɯƜβ] and [ɯƜv], which have more labial constriction than [u], exhibit reduced back raising activity compared to [u]. We additionally report on correlations between lingual activity and labial activity based on the frontal lip shape and lip aperture data collected from a time-aligned video channel.
Acoustical emphasis not possible: The case of emphatic morphemes in Lakota
Authors: Kidner Brooke L.
Published: April 2019

In languages like English, emphasis can be expressed acoustically by an increase in pitch or amplitude. These types of pitch excursions and increase in amplitude are often how metrical stress is marked in languages. This type of representation of metrical stress is true for Lakota. While this type of acoustic representation of stress is not uncommon, it does present a unique problem for Lakota speakers when it comes to encoding emphasis acoustically in their speech. Lakota (a member of the Dakota family of languages with less than 9000 speakers), has a very rigid set of rules for where stress can be applied in languages, often having several minimal pairs that differ only in which syllable receives primary stress. As such, they are unable to utilize these common acoustic markers for emphasis in their speech. Field research conducted on the Pine Ridge Reservation (2018, 2016) has resulted in the discovery that Lakota possesses two emphatic morphemes: [kʃto] for female speakers and [jelo] for males, which speakers utilize to encode emphasis into their speech.
Tahrir patterns in a professional Iranian classical singer
Authors: Tahamtan Mahdi , Scherer Ronald
Published: April 2019

“Iranian classical singing” (“avaz” in Persian) contains the ornament called a tahrir. It typically is a sequence of tekyeh fundamental frequency gestures that quickly increase and then decrease. The primary aim was to determine and describe the tahrir patterns produced by a professional avaz singer. An unaccompanied recording was made of a professional avaz singer singing the popular song “Morghe Sahar” (“Dawn Bird”). Consistent patterns of tahrir productions were determined after repeated listening. Four primary tahrir patterns were identified, based on (1) the number of tekyehs within the tahrir, (2) fundamental frequency extent from the baseline to the tekyeh peaks, and (3) inter-tekyeh interval durations. Pattern 1 consists of one tekyeh and is called a “zinat.” Pattern 2 is a multiple tekyeh gesture with relatively long inter-tekyeh intervals. Pattern 3 is a multiple tekyeh gesture with relatively short inter-tekyeh intervals. Pattern 4 is a vibrato-like pattern with multiple tekyehs with short inter-tekyeh intervals like Pattern 3 but with relatively short frequency extents. The results are pertinent to voice scientists interested in the mechanics of phonatory production, to singing teachers and artists interested in pedagogy based on acoustic and perceptual information, and to ethnomusicologists interested in cultural musical performance and production.
Coarticulatory resistance in Assamese stops
Authors: Dutta Indranil , Gogoi Pamir , Wayland Ratree
Published: April 2019

The nature and extent of coarticulation and coarticulatory resistance of speech segments have been found to be dependent on the size, shape, and density of contrasts, in addition to neighborhood densities of segment sequences. While high density of contrasts leads to high coarticulatory resistance, low density of contrasts leads to low coarticulatory resistance. Assamese, an Indo-Aryan (IA) language, unlike the other IA languages which exhibit a two-way coronal place contrast, contains only an alveolar stop. Due to the relative low density of the alveolar, we hypothesize that the Assamese alveolar stops will exhibit low coarticulatory resistance compared to the velar counterpart. We use locus equations to analyze the coarticulatory effects. First order locus equations were used in a [aCV_] context, where C is a labial, alveolar, or velar stop, while the following V is one of the corner vowels /a,i,u/. Unlike the hypothesis, the least amount of coarticulatory resistance is shown by the velars and the alveolars show greater resistance compared to the velars and the labials. This poses an interesting question because it has been stated that mostly the slopes are seen to be order of labial, then velar and then alveolar. The possible explanations are discussed.
Effect of stress, harmonic status, and lexical status on Hungarian vowel-to-vowel coarticulation
Authors: Conklin Jenna , Dmitrieva Olga
Published: April 2019

The present study examines vowel-to-vowel coarticulation in Hungarian with particular emphasis on the effects of word stress and lexical status (real words versus nonce words) on the direction and degree of vowel coarticulation. Previous investigations indicate that lexical stress exerts a powerful influence on vowel coarticulation. Specifically, stressed vowels are thought to resist coarticulation (see, e.g., Beddor et al., 2002; Majors, 2006). It is not clear, however, whether this effect is universal across languages, nor if it can be suppressed by the presence of more influential factors. In addition, it is not known whether vowel-to-vowel coarticulation always affects real and nonce words in a similar fashion, though some previous research indicates that speakers differ in their coarticulatory handling of nonce words (Scarborough, 2012). Finally, previous research suggests that the presence of vowel harmony in a language may place restrictions on the direction of vowel-to-vowel coarticulation (Beddor and Yavuz, 1995). Hungarian has a vowel harmony system that includes several neutral vowels, which do not participate in harmony. This study reports the results of an acoustic analysis of coarticulation in stressed and unstressed vowels (both neutral and harmonizing) in real and nonce words produced by native speakers of Hungarian.
Tracking sources of formant frequency variation in data from a time-controlled speech production task
Authors: Flego Stefon M.
Published: April 2019

Vowel formant structure is particularly sensitive to influence from neighboring segments in connected speech. Statistical models can successfully account for acoustic variability from multiple simultaneous sources of variance, such as anticipatory effects of following consonants and vowels (see, for example, Cole et al., 2010). Statistical approaches have also been developed to predict context segments from static measures of spectral variation like mean or midpoint formant frequencies. This study examines shifts in the relative strength of these sources of variance over the course of the target vowel, and compares previous approaches to predicting the identity of upcoming segments with a novel approach which is cumulatively informed by formant frequency variation as it unfolds temporally. Data are from 32 participants who produced target-context word sequences (permutations of …V1C#hV2…, where V1 = [ɛ], C = [θ f], and V2 = [i ɛ æ ɑ u], e.g., “deaf-heating”) within a carrier sentence. Timing and prosody were strictly controlled by entraining the syllable rate to a metronome. Context word onset was always [h], which has no intrinsic supralaryngeal articulation and only begins foot-initial syllables in English. This ensured a consistent prosodic boundary between target and context words and prevented resyllabification of C across words.
A comparison of prosodic patterns in English bi-morphemic lexical and function words
Authors: Shport Irina A. , Johnson Gregory
Published: April 2019

In English, monosyllabic function words (them, in) are prosodic clitics, but the prosodic status of multisyllabic function words (whenever, everybody) is not well understood. We compared fundamental frequency (F0) patterns in function and lexical compounds to determine whether the words formation process, compounding, is associated with a certain prosodic template. F0 was examined because of vowel-intrinsic differences in duration and intensity, the other two correlates of prominence. Four speakers of Appalachian English from Kentucky read sentences with words of three types in the sentence-medial position: two relative pronouns (whatever, everwhat), two quantifiers (everyone, everyone), and six lexical words (e.g., wallflower, evergreen). F0 ratios between stressed vowels in two morphemes of each word were calculated. The results showed that the ratios were higher in lexical compounds than in quantifiers and in free relative pronouns, which were not different from each other. These results suggest a pattern of the first-morpheme (left-constituent) prominence in lexical words, similar to previous reports on adjective + noun compounds, and a pattern of the second-morpheme (right-constituent) prominence in function words, similar to morphologically complex but non-compound words. The proposed right-prominence prosodic template for multi-morphemic function words is discussed in relation to phrase-level accents and boundary tones.
Methods for noise reduction in a legacy speech corpus
Authors: Lipani Lisa , Shi Yuanming , McNeill Joshua , Renwick Margaret E.
Published: April 2019

The Digital Archive of Southern Speech is an audio corpus featuring interviews conducted from 1968 to 1983, with speech from 30 female and 34 male southern speakers, totaling 372 h of audio data. However, automated analysis of this data has been made difficult by background noise in this legacy corpus, originally recorded on reel-to-reel tape and later digitized to .wav format. In this paper, we compare the effect of noise reduction techniques on the acoustic signal and evaluate their effect on acoustic speech data. We use Praat to detect the quietest silence (measured using root-mean-square amplitude) in each sound file. The audio data contain silences that lack background noise (e.g., due to anonymization procedures), but these are excluded from selection. Each quietest silence is used to create a “noise profile,” which is removed from the audio using a scripted noise removal procedure in both Audacity and SoX. The success of each procedure is assessed with three-way comparisons of the amplitude of silences in uncleaned and cleaned audio, and vowel plots made with formant values extracted from uncleaned and cleaned audio. It is predicted that successful noise reduction will reduce the number of outliers occurring in F1, F2 space.
An articulatory analysis of asymmetrically confusable consonants
Authors: Calloway Ian
Published: April 2019

Acoustic similarity and articulatory similarity do not always co-occur; a narrow range of acoustic outcomes can sometimes correspond to a comparatively wide range of articulatory parameters (Stevens, 1989). The articulatory parameters associated with a narrow window of acoustic events occasionally straddle a category boundary—some consonants (e.g., /t/ and /k/ in front vowel contexts) show acoustic (and perceptual) similarity with one another, despite differences in active articulator or place of articulation (Plauché, 2001). This study utilizes a corpus of vocal tract MRI (Sorensen et al., 2017) to relate the spatial dynamics of productions of /p/, /t/, /k/, /f/, and /θ/ to their acoustic properties. This analysis offers insight into why articulatorily dissimilar productions can show increased spectral similarity and how phonetic context conditions this similarity. For each segment production, five video frames were extracted—one frame before constriction release, and four after release. From each frame, a 30-point cross-sectional area function of the vocal tract airway was generated. Vocal tract parameters associated with the spectral properties of frication, aspiration, and stop bursts were analyzed. In phonetic contexts favoring misidentification, confusable segment pairs show greater similarity in vocal tract regions anterior to the primary constriction.
Definite determiner realization in the Philadelphia neighborhood corpus
Authors: Arlin Jennifer B.
Published: April 2019

Systematic variation in the pronunciation of the definite determiner (orthographic the) is well-known; the general rule is that preconsonantal /ðə/ alternates with prevocalic /ði/. Nonetheless, widespread deviation from this rule has been noted, most recently by Meyerhoff (2018) (examining definite determiner pronunciation in various populations in New Zealand). This project studied the realization among a small sample of female speakers in the Philadelphia Neighborhood Corpus. All were L1 English speakers, born between 1950 and 1986 and interviewed between 1973 and 2010. The determiner was hand-coded throughout their interviews for pronunciation and for nature of the following segment (vowel- or consonant-initial, as uttered). The data were then analyzed to determine whether age or following segment influenced realization as /ðə/ or /ði/. Results indicated a high degree of adherence to the canonical rule, showing preconsonantal /ðə/ 97% of the time and prevocalic /ðə/ 18% of the time. While the rate of occurrence of prevocalic /ðə/ was generally quite low, it did vary significantly by speaker. The younger generation on average tended to use prevocalic /ðə/ slightly more often than the older generation; individual variations made it impossible to draw any conclusions about a meaningful connection between age and variation.
Reference speaker selection for kinematic-independent acoustic-to-articulatory-inversion
Authors: Bozorg Narjes , Johnson Michael T.
Published: April 2019

This paper investigates the most effective reference speaker set for the Parallel Reference Speaker Weighting (PRSW) algorithm for kinematic-independent acoustic-to-articulatory inversion. To obtain the adaptation weights for estimating the articulatory model, different reference speaker accent types and quantities have been acquired. The reference speaker sets have been selected not only based on their performance in speaker-dependent kinematic-inversion but also based on the type of accent. The experiments have been conducted on parallel Acoustic-Articulatory data, the Marquette Electromagnetic Articulography corpus of Mandarin Accented English (EMA-MAE) consisting of 20 native English speakers and 19 native Mandarin speakers of English. A comparison is made between different types of target speakers and reference speakers with results indicating that the accuracy of the adapted model increases when we select balanced distributed accents of English and lower number of speakers.
Development of an in-air circular synthetic aperture sonar system as an educational tool
Authors: Blanford Thomas E. , McKay John D. , Brown Daniel C. , Park Joonho D.
Published: April 2019

Synthetic aperture sonar (SAS) is an underwater acoustic imaging technique that is used to generate high quality imagery through the coherent combination of signals measured on a moving platform. The practical challenges of underwater experimentation and the lack of publicly available data sets make it difficult to teach SAS processing to students using experimental data. These challenges are compounded by the complicated signal processing that is required to compensate for the unwanted platform motion that is common in field data. This presentation will detail the development of an in-air circular SAS system using commonly available laboratory equipment. By operating in air and using a circular geometry many of the challenges that students would otherwise encounter in SAS processing are either well controlled or completely eliminated. Imagery collected on the system will be displayed to demonstrate how meaningful data can be generated using a simple set of equipment. A number of applications of the system as a tool to teach array signal processing, pulse compression, and imaging concepts will be discussed as well.
Evaluation of underwater acoustic images obtained by the early stage monotone pulse-echo Synthetic Aperture Sonar
Authors: Baik Kyungmin , Park Seung-Soo , Kye Joong Eup
Published: April 2019

Synthetic Aperture Sonar (SAS) is a side-looking underwater acoustic imaging sonar that can obtain higher resolution images than those by the conventional Side Scan Sonar (SSS). Due to its high resolution images, it can be applied to various fields of studies from military to civilian purposes. Republic of Korea recently has launched a research project developing the prototypes of SAS being operated in a few hundreds kHz of acoustic signals. This project adopted the towfish as the SAS platform that are to be towed under a few tens of water depth, which has a price advantage over Autonomous Underwater Vehicle (AUV), but gives unstable motion. It also adopted the monotone pulse-echo mode as transceiver method of the prototypes that gives relatively simpler implementation of the data acquisition module although it gives inferior SNR to the chirp mode. In the current study, the underwater acoustic images of the protype SAS taken both in the fresh water and offshore of Korea are to be shown. Current study also shows the evaluation method of image resolutions using test targets simulating point scatterers. Resulting images are to be compared with the images by the conventional SSS through the evaluation of the resolution. As is well known, although SAS generated clearer underwater images than SSS images, phase uncertainty of the array is critical factor determining the image resolution of SAS that is heavily degradated by the unwanted motion of the SAS platform.
A FNN for source range and ocean environment classification using time-domain features
Authors: Van Komen David F. , Knobles David P. , Neilsen Tracianne B. , Badiey Mohsen
Published: April 2019

Acoustic source ranging in an uncertain ocean environment is a complicated problem, though classification and regression-based machine learning algorithms show promise. A feedforward neural network (FNN) has been trained to do either classification or regression on both the source-receiver range and environment type using extracted time-domain features. Time waveforms are generated to simulate signals received at different ranges in three different environments with a sandy, muddy, or mixed sediment bottom. Four features are extracted from these waveforms: peak level, integrated level, signal length, and later decay time. These four features are used to train FNN for both classification and regression of range and environment type, and the results are compared to a network trained on the time waveforms. For small amounts of training data, the extracted features provide a higher accuracy than the full waveform. Thus, physics-based feature selection via preprocessing can lead to fairly accurate results when using a FNN with small datasets. These results lay a foundation for comparisons to the more computationally expensive convolutional neural networks. [Work supported by the Office of Naval Research.]
Replicating a below-band linear field in a refracting sound channel via a caustic-corrected autoproduct
Authors: Geroski David J. , Dowling David R.
Published: April 2019

Frequency difference source localization methods have achieved some success in uncertain underwater environments by taking advantage of the frequency difference autoproduct—a quadratic product of two complex field amplitudes at different frequencies but from the same location and recorded signal. The phase of the frequency difference autoproduct is less sensitive to unknown propagation complexities than that of the in-band field from which it is derived. The noted localization success arises in some technologically relevant scenarios when the frequency difference autoproduct at least partially mimics a genuine acoustic field at the difference of the two frequencies. However, the nonlinearity inherent in the autoproduct can lead to salient and even counter-intuitive differences between it and a genuine below-band field in the same environment. This presentation explores methods for correcting the phase differences that arise between autoproducts and genuine fields in refracting multipath environments that lead to the formation of caustics. This presentation illustrates the effectiveness of utilizing these methods to localize sources using propagation simulations in a refracting environment, and 200 to 300 Hz PhilSea10 propagation data (Worcester et al., 2013) collected in a deep-ocean sound channel at source-array ranges of hundreds of kilometers. [Work supported by ONR.]
Block-sparse compressive localization for incipient tip vortex cavitation noise
Authors: Park MinSeuk , Seong Woojae , Choo Youngmin , Park Yongsung
Published: April 2019

Marine propeller cavitation is a dominant noise source of ships. Thus, localizing the cavitation noise source is essential for subsequent remedy. Given that incipient tip vortex cavitation (TVC) noise radiates in all directions as a monopole source and a few noise sources exist in the vicinity of the propeller, the localization problem can be considered as a sparse signal reconstruction problem. Compressive sensing (CS) based localization technique utilizes a sparsity promoting constraint and solves the localization problem efficiently with high resolution. Block-sparse CS, based on block-sparsity, is adopted to process multiple frequency components of the sources coherently. Block-sparse CS localization of TVC shows superior performance with high resolution compared to the conventional CS based incoherent multiple frequency processing. To demonstrate the performance of the block-sparse CS localization, both synthetic and real cavitation tunnel experiment data are used.
Continuously capturing circulating cancer cells
Authors: Kulkarni Rajan P.
Published: April 2019

A wearable apheresis device allows for continuous and specific capture of circulating tumor cells.
Periphyton and Flocculent Materials Are Important Ecological Compartments Supporting Abundant and Diverse Mercury Methylator Assemblages in the Florida Everglades
Authors: Bae Hee-Sung , Dierberg Forrest E. , Ogram Andrew
Published: April 2019

Methylmercury is a potent neurotoxin that impacts the health of humans and wildlife. Most mercury in wetlands such as the Florida Everglades enters as inorganic mercury via atmospheric deposition, some of which is transformed to the more toxic methylmercury through the activities of anaerobic microorganisms. We investigated the numbers and phylogenetic diversity of
hgcAB
, genes that are linked to mercury methylation, in the soil, floc, and periphyton in areas of the Everglades with different sulfate and nutrient concentrations. Soil harbored relatively high numbers of cells capable of methylating mercury; however, little detectable methylmercury was present in soil. The greatest concentrations of methylmercury were found in floc and periphyton. The dominant methylators in those compartments included methanogens and
Syntrophobacteriales
. This work provides significant insight into the microbial processes that control methylation and form the basis for accumulation through the food chain in this important environment.
Complete Genome Sequence of Klebsiella pneumoniae Myophage Menlow
Authors: Newkirk Heather N. , Lessor Lauren , Gill Jason J. , Liu Mei
Published: April 2019

Klebsiella pneumoniaeis an opportunistic pathogen that has become an increasing problem in nosocomial infections. Studying phages that infectK. pneumoniaemay lead to improvements in phage therapeutics for treating these infections.
Draft Genome Sequence of the Wood-Staining Ascomycete
Chlorociboria aeruginascens
DSM 107184
Authors: Büttner Enrico , Liers Christiane , Gebauer Anna Maria , Collemare Jérôme , Navarro-Muñoz Jorge Carlos , Hofrichter Martin , Kellner Harald
Published: April 2019

Chlorociboria aeruginascens
DSM 107184 is a wood-decomposing ascomycetous fungus known to produce the bluish-green dimeric naphthoquinone derivate xylindein. Here, we present the first draft genome sequence, which contains 588 contigs with a total length of 33.1 Mb.
Complete Genome Sequence of Oxidase-Positive Stenotrophomonas maltophilia Strain SM7059
Authors: Gao Shuo , Zhang Zhifeng , Zhou Hui , Zhu Hong , Shen Han , Zhou Wanqing
Published: April 2019

Stenotrophomonas maltophilia
is an opportunistic pathogen which causes an increasing frequency of infections in hospitalized patients. Here, we present the complete genome sequence of
Stenotrophomonas maltophilia
SM7059, an oxidase-positive strain isolated from a female patient with hepatolithiasis in China.
PO 8467 IMPACT OF COMMUNITY CASE MANAGEMENT OF MALARIA (CCMM) AMONG CHILDREN UNDER FIVE YEARS OLD: AN EVALUATIVE STUDY IN KABONGA
Authors: Bonne Ciza , Husseni Kagozi , Muhigirwa Ciza Josephine
Published: April 2019

Background

In Burundi, malaria is considered a major public health concern and the leading cause of death. Malaria is responsible for up to 25% of all outpatient visits and up to 48% of all deaths in health facilities among children under five years old. Despite efforts made, timely access to health care is still limited, mainly due to geographic inaccessibility and lack of awareness about malaria complications. To increase timely access to malaria treatment, Burundi’s Ministry of Health implemented Community Case Management of Malaria (CCMM) since 2015 in Kabonga. We sought to assess the impact of CCMM in improving malaria outcomes following two years of its initiation.

Methods

Selected community health workers (CHWs) were initially trained for simple malaria management among children under five years old using artemisinin-based combination therapy (ACT) and to perform rapid diagnostic tests for malaria (RDTs), and then equipped to provide service. This was a retrospective and prospective study using a mixed-methods approach between September-October 2017. Data before CCMM initiation (2013–2014) were collected from the Kabonga health centre, then compared to data from 2015–2016 corresponding to CCMM implementation. Data were from health records and stakeholders and were processed using SPSS.

Results

In total, 5922 children were treated for malaria between 2013–2014 and 5249 between 2015–2016, an 11,3% case decrease. CHWs managed in total 1751 children using ACTs between 2015–2016. Of them, 1297 (74%) had a consult within 24 hours of fever onset and the cure rate was approximately 90%. Mortality decreased with up to 75%. Ownership level was encouraging among beneficiary communities and was low among district and health center’s staff. Some stock-outs were also reported.

Conclusion

Using trained CHWs increased access to timely and appropriate treatment in sampled communities which was associated with improved health outcomes among children under 5 years old. However, regular supply to CHWs and strong ownership is needed.