bluuebunny/crossref_metadata_2025 huggingface dataset:
Journey to Antarctica: Modeling crustal structure with an earthquake and a genetic algorithm
Authors: Brownlow Priscilla , Brazier Richard , Nyblade Andrew
Published: November 2013

In a previous work, we have used the genetic algorithm NSGA-II to generate a set of solutions to model the receiver functions and dispersion curves of several seismometer stations located in southern Africa. Now in continuation of applying the NSGA-II to seismic problems, we have used it to model the average velocity profiles along two-dimensional paths from a single seismic event to several stations across West Antarctica. The event was a rare continental earthquake of magnitude 5.6 that took place in West Antarctica near the Ross Ice Shelf during the austral winter of 2012. Data were collected from stations in the Global Seismic Network as well as a local network during the 2012–2013 field season. The seismograms were first modeled using a full body wave modeling code that generates synthetics based on a structure composed of layers with user-defined velocities, thicknesses, and densities. Those models then served as the starting models in NSGA-II, which created a set of solutions from which an average structure with error bounds was calculated for each station.
Physics-based inversion of multibeam sonar data for seafloor characterization
Authors: Hefner Brian T. , Jackson Darrell R. , Ivakin Anatoliy N. , Wendelboe Gorm
Published: November 2013

As part of a continuing effort to develop a physics-based seafloor inversion technique, both acoustic and environmental data were collected during the Target and Reverberation Experiment 2013 (TREX13). The data were collected along a 350 m long survey track that sampled several sediment types including sand, silty-sand, and mud. A RESON 7125 multibeam sonar was modified to collect data along the track from 150-450 kHz in 50 kHz intervals. Ground-truth data on seafloor properties were acquired along this track, including measurements of roughness, sound speed, attenuation, and both discrete and continuous volume heterogeneity. A model was used to generate echo intensity time series including scattering by both seafloor roughness and volume heterogeneity. Model-data fits were used to provide estimates of acoustic attenuation, volume scattering strength, and roughness spectral parameters. Volume scattering is treated using an empirical model, while roughness scattering is treated using the small-slope approximation. [Work supported by SERDP.]
Seafloor sound-speed profile and interface dip angle measurement by the image source method
Authors: Pinson Samuel , Holland Charles W.
Published: November 2013

The image source method is an efficient way to perform a sound-speed tomography for seafloor characterization. To date, however, it has been limited by a locally range-independent approximation for layer boundary geometry. In other words the layer boundary had to be parallel and flat within 1 Fresnel zone of the measurement system. Here, the method is extended to take into account realistic variations of interface dip angles. To do so, the elliptical wavefront shape approximation of the reflected waves is used. This permits a fairly simple equation relating travel time to the sine of the dip angle, and consequently to an equation for the equivalent medium sound-speed. The Radon transform is exploited to extract this dip angle parameter. Simulations with varying layer dip angles and curvature provide insight into the strengths and limitations of the method.
Reflection-coefficient inversion for compressional- and shear-wave dispersion in porous and elastic layered media
Authors: Dettmer Jan , Holland Charles W. , Dosso Stan E.
Published: November 2013

This paper considers Bayesian inversion of seabed reflection-coefficient data for the compressional- and shear-wave velocity dispersion and attenuation-frequency dependence in arbitrarily layered porous and elastic media. The seabed is modeled using Buckingham's viscous grain shearing model which obeys causality. Seabed layers are parametrized in terms of six fundamental parameters, including thickness, porosity, compressional and shear grain-to-grain moduli, material exponent, and the compressional visco-elastic time constant. These fundamental parameters are used to compute density, compressional- and shear-wave dispersion curves, and compressional and shear attenuation-frequency curves for each layer. The curves are used in the inversion to predict spherical-wave reflection coefficients as a function of frequency (300–3000 Hz) and grazing angle (12–75 degrees), which include the effects of shear waves in arbitrarily layered media. In addition, the seabed layering is estimated from the data by applying a trans-dimensional Bayesian model. The ability to resolve shear-wave velocity and attenuation structure is studied using simulated data. Finally, compressional- and shear-wave dispersion are presented and discussed from measured reflection data at a sandy site in the Tyrrhenian Sea. [Work supported by ONR Ocean Acoustics.]
Real-time physical models of musical instruments: Applications and findings
Authors: Pfeifle Florian , Bader Rolf
Published: November 2013

Real-time auralization of physical models has attracted vivid interest over the last years. This is mainly due to the rising computational capabilities of personal computers and the accessibility of specialized (external) accelerating hardware, like GPGPUs (general-purpose graphics processing units) or FPGAs (field programmable gate arrays). In this work, an extended framework of real-time physical models of musical instruments, calculated with symplectic and multi-symplectic finite difference algorithms, on a FPGA is presented. The former study, as presented in earlier publications by the authors, is extended in three aspects: (a) A methodology for coupling FPGA boards via a highspeed general purpose IO, to facilitate calculations of larger instrument geometries, such as piano sound-boards, is implemented. (b) A generalized design structure for all models is developed. (c) An enhanced external interface communication protocol is realized. These extensions resulted in several new possible applications for music and for musicological research.
Embedded physical modeling synthesis in three dimensional environments
Authors: Bilbao Stefan
Published: November 2013

3D audio rendering of virtual spaces, for purposes of artificial reverberation, or in concert hall auditioning has seen great advances in recent years. Of particular interest are wave based techniques, such as finite difference time domain methods. Such methods are computationally intensive, and parallel architectures, such as GPGPUs, can be of use in accelerating computation times. A further use of such methods is in synthesis—through the embedding of physical models in a three dimensional space, allowing the complete spatial rendering of the acoustic field. In this paper, a variety of membrane- and plate-based percussion instruments will be discussed, with special emphasis on implementation issues in parallel hardware. Sound examples will be presented.
Computation and simulation of frequency variations in musical instrument sounds
Authors: Beauchamp James W.
Published: November 2013

Frequency variations of musical instrument sounds were measured using phase-derivative and frequency-tracking methods based on the short-time Fourier transform. Frequency variations are important features of instrument sounds and are very useful for musical expression. Three categories of variation are: vibrato, portamento, and microvariation. Microvariations exist even when a tone is played at a constant pitch, and they can be approximated as small frequency-deviation low-frequency noise signals. Portamento is a purposeful pitch glide embellishment that can occur during attacks, between notes, or, less often, at the ends of notes. Vibrato can be characterized as an approximately sinusoidal frequency variation, and usually its amplitude is sufficient to interact with instrument resonances and cause significant harmonic amplitude modulations. Deviation amplitudes and frequencies of acoustic instrument vibratos are not perfectly steady, but rather vary over the durations of instrument tones. Measurements of vibrato characteristics of the harmonic frequencies and amplitudes as well as the frequency and amplitude microvariations of various instruments and voice indicate that a variety of parameters are required for effective instrument synthesis. The challenge in synthesis is to avoid a “mechanical sound.”
Haptic interaction design using Synth-A-Modeler
Authors: Berdahl Edgar J.
Published: November 2013

Synth-A-Modeler is an open-source and modular software environment for designing physical models using a mechanical analog approach. Notably, physical models provide the most reliable method for programming haptic force-feedback interactions that can be ported across a wide array of haptic devices and usage scenarios. In this presentation, we explain how Synth-A-Modeler facilitates teaching haptic interaction design, with an emphasis on audio-haptic interaction. A series of example models demonstrates how mass-interaction, modal synthesis, and digital waveguide elements, as well as combinations thereof, can be employed in Synth-A-Modeler to simulate virtual audio-haptic environments. Although Synth-A-Modeler can hide the details of the model implementations, some equations are employed to calibrate the models. The models are tested with the FireFader open-source haptic device; however, the models should be compatible with a wide array of other haptic devices and DSP targets as well.
Physical modeling of musical instruments on handheld mobile devices
Authors: Scandalis Gregory P. , Smith Julius O. , Porcaro Nick
Published: November 2013

Handheld mobile computing devices are now ubiquitous. These devices are powerful, connected and equipped with a variety of sensors. Their pervasiveness has created an opportunity to realize parametrically controlled, physically modeled, virtual musical instruments. We will present a brief history of physically modeled musical instruments and the platforms that those models have been run on. We will also give an overview of what is currently possible on handheld mobile devices including modeling done in the “moForte Guitar” mobile application. “moForte Guitar” is an application for mobile devices that models the physics of the guitar family of instruments. Modeling makes expressive interactive articulation possible, which cannot be directly achieved with sample playback techniques. Features that are modeled include: electric and acoustic instruments, strumming at various string positions, string scraping and damping, harmonics, glissando, automated modeling of strumming, statistical variation of physical parameters, feedback/distortion and classic processed electric guitar effects. We will show a number of real-time demonstrations on a handheld mobile device for what is possible with this model.
Spectrally accurate numerical solution of acoustic wave equations
Authors: Amuedo John W.
Published: November 2013

Finite difference models of wave propagation have presented challenging problems of stability and accuracy since initial experimentation with these models began on early digital computers. The advent of spectral methods in the late 1960s has led to the latter's increasing use for solving differential equations in a range of fluid dynamic, electromagnetic and thermal applications. Spectral methods transform a physical grid of state variables (such as acoustic velocity and pressure) into an alternative spectral space characterized by a particular set of basis functions. Spatial derivatives of physical state variables are computed in spectral space using exact differential operators expressed in terms of those functions. Fast numerical transforms are employed to exchange immediate state of a simulation between its spectral and physical representations. In problems equally suited to spectral and finite difference formulation, spectral methods often yield increased fidelity of physical results and improved stability. Spectral methods sometimes enable computational grid size requirements of a simulation to be substantially reduced, with concomitant computational savings. This paper reports on spectral implementations of the acoustic wave equation and Webster horn equation for simulating audio transducer cavities, musical instrument resonators, and the human vocal tract.
The mother tongue of organ pipes-Synchronization, experiments, numerical simulations, and model
Authors: Fischer Jost , Abel Markus
Published: November 2013

We present recent results on the synchronization (Mitnahme Effect) of organ pipes. Previous work has focused on the detailed measurement and reconstruction of the driving of an organ pipe by a loudspeaker. As a result the full Arnold tongue was measured and reconstructed and a synchronization could be found down to a fraction of 1/500 of the sound pressure level of the organ pipe. In this contribution, we give detailed results on the experimental determination of the Arnold Tongue for two pipes. The results are accompanied by detailed numerical simulations of sound generation and sound radiation with the aim to clarify the interaction of the jets and the dependence of the synchronization region on coupling strength (realized by varying distance). Furthermore, we propose a model for the coupling function.
Aural ordinary differential equations: Methods for generating audio from mass-spring systems
Authors: Allen Andrew S.
Published: November 2013

In this article, I focus on the harmonic oscillator as a model by which to compare several numerical methods for solving ordinary differential equations (ODEs). I first define the simple harmonic oscillator as an ODE and then extend its behavior by adding additional forces and physical properties to the equation. I next proceed to discuss computational methods for solving ODEs and use the oscillator model as a means of evaluating and comparing three methods in terms of their stability, drift, and computational costs when working at the audio-rate.
Normalization and matching routine for comparing first and second language tongue trajectories
Authors: Moriya Shusuke , Yaguchi Yuichi , Terunuma Naoki , Sato Takahiro , Wilson Ian
Published: November 2013

The main purpose of this research is specifying the articulation difference between L1 and L2 speakers by digitizing tongue motions and analyzing their differences between utterances. Differences in tongue motion directly influence speakers' pronunciation, so it may be possible to determine a speaker's L1 from tongue motion data. By comparing L1 and L2 speakers' tongue motion, we can also guide L2 speakers to improve their L2 pronunciation. In this research, we use coronal cross sections of the tongue taken by an ultrasound scanner to carry out the following: first, record the ultrasound of a speaker's tongue motion using the story “The Boy Who Cried Wolf.” Then, sample mobility information by using histogram of oriented gradients. Next, use Karhunen-Loeve expansion to reduce the vector dimensions. At this time, we get the average difference between the starting vector of tongue motion and the subsequent vectors, then normalize the direction of the two averages. Finally, we use dynamic time warping to compare each vector per frame. The experiment results allowed us to compare speakers' tongue mobility information in words which were recorded in different experiment environments or by different speakers.
Perceptual and phonotactic effects in loanword adaptation: English postvocalic stops in Taiwan Mandarin
Authors: Chang Jui Ching
Published: November 2013

When an English word with a postvocalic stop is borrowed into Taiwan Mandarin (TM), because TM allows only nasal coda consonants, an often-used strategy to repair the illegality is vowel-insertion (e.g., Wood → [wu.tv̥]). Based on a corpus study of 335 English borrowed names, this trend is confirmed (76%). Among the deleted cases, an asymmetry of different places of articulation was found: Coronal stops are deleted most often (15%, e.g., Hollywood → [hau.lai.wu]), and dorsals more often than labials (12%, e.g., Titanic → [thiɛ.ta.ni] vs 0%, e.g., Jeep → [tɕ. phu]). Following Kang’s (2003) perceptual explanation, the tendency of coronal-deletion can be explained by the fact that postvocalic coronals are often unreleased and thus less perceptually salient to TM speakers. According to TIMIT corpus, the release rate of coronals, labials, and dorsals stops is 37%, 52%, and 83%, respectively (Kang, 2003). However, this cannot explain the reversed pattern of dorsals and labials. I propose that this is due to another factor: Labial coda is marked in TM since only [n] and [ŋ], but not [m], can occur in coda position. In other words, the deletion of postvocalic stops depends on the saliency that considers both perceptual and phonotactic factors.
The effect of language distance and language experience in third language acquisition
Authors: Chang Seung-Eun
Published: November 2013

This research aims to examine the role of second-language (L2) phonology in third-language (L3) acquisition. As a mean to assess the degree of influence of the L1 accent and L2 accent in L3 production, an experiment that involved the judgment of a foreign accent was developed. Two groups of native English speakers [(i) five who had not learned any language other than Korean, and (ii) five who had learned Japanese before learning Korean] produced Korean sentences, and 25 native Korean-speaking raters identified each production according to the speaker’s dominant accent, either English or Japanese. The results revealed that native English speakers who had learned Japanese before learning Korean were more frequently identified as having a strong Japanese, rather than English, accent in their Korean production. In accounting for the results, several hypotheses were discussed, including language distance (typological proximity), inherently different mechanisms for foreign language acquisition as compared with the natural acquisition of the L1, psycho-affective factors, and stronger links between foreign languages in the speaker’s mind. The findings of this study provide further evidence for the claim that L2 exerts an influence on L3 accent; however, this interference is reduced with an increase in L3 proficiency
Acoustic measurement of word-initial stop consonants in English-French interlingual homophones
Authors: Castonguay Paula , Andruski Jean E.
Published: November 2013

The purpose of the present study is to examine word-initial stop consonants of Canadian English (CE) and Canadian French (CF) interlingual homophones in order to describe how they differ in their acoustic properties. Interlingual homophones (IH) are words across languages that are phonemically identical but phonetically and semantically different, for example, English two /tu/ and French tout  /tu/. Even though they are deemed phonemically identical, at the acoustical level they may be quite different. In the current study, Canadian bilingual English and French speakers were asked to produce interlingual homophones embedded in carrier phrases and in isolation. Voice onset time, relative burst intensity, and burst spectral properties of the IH words were measured and compared within and across languages. The acoustic measurements obtained will be used (1) to make predictions about which acoustic features may provide cues to language identity, and (2) to create stop tokens for a Goodness Rating study. Results from this study will provide insight on the acoustic-phonetic representation of stop consonants in Canadian bilingual English and French speakers.
Influence of second language on the perception of third language contrasts
Authors: Onishi Hiromi
Published: November 2013

The influence of L2 knowledge on the perception of L3 contrasts was examined in several experiments with two groups of Korean learners of Japanese. All participants have studied English as an L2 prior to beginning their study of Japanese as an L3. One group participated in a forced-choice identification experiment, and the other group participated in an AXB discrimination experiment with various Japanese contrasts. Additionally, both groups participated in a forced-choice English minimal pair identification experiment. Correlation between each group’s performance in the Japanese experiment and the English experiment was examined in order to determine whether the perceptual level in English has any influence on the identification and discrimination of Japanese contrasts. The results of the correlation analysis suggested that the participants used increased knowledge in the L2 in a direct manner. That is, the better the participants performed on the L2 contrasts the better they also identified the L3 contrast, which is known to be difficult for them. During the L3 discrimination experiment, however, the participants seem to have used their increased L2 knowledge in a general manner. These results are considered an indication of L3 learners’ general enhanced sensitivity as a result of the experience in L2 learning.
Does first language prosodic transfer affect second language prosody?
Authors: Lomotey Charlotte F.
Published: November 2013

Learners of English have been found to transfer their L1 prosody into the prosody of L2 (Ramírez Verdugo, 2006). However, the effect of this transfer is not known or may not be universal. Besides, while English uses fundamental frequency in its intonation system, to indicate prominence in syllables and in phrases, and to signal differences in sentence intonation, Awutu uses it to signal lexical tone, a common phenomenon of tone languages. The present study investigates the effect of transfer of some prosodic features of Awutu, a language of Ghana, on English. To achieve this, 10 speakers of Awutu who are non-native speakers of English were asked to read narrow and broad focus statements and questions in both Awutu and English. The data were subjected to acoustic analysis for fundamental frequency using the Computerized Speech Laboratory. Preliminary findings show that Awutu speakers of English raise their fundamental frequency on focused words to show prominence. However, the pitch tracks of both statements and questions show that even though these speakers transfer some sentence prosody from Awutu, they do not show any consistency in the transfer. These findings suggest that the nature of L1 prosodic transfer into L2 may be language-specific.
Realization of Thai tone change in the Northern Thai dialect of Chiang Mai
Authors: Hoffmann Maureen
Published: November 2013

Recent studies have found evidence of tone change in progress among Thai speakers. In particular, changes in the high tone, traditionally considered a level tone, have caused some to suggest it should instead be considered a contour tone (Zsiga, 2008; Teeranon and Rungrojsuwan, 2009). However, the previous research has focused primarily on the Central Thai dialect found in Bangkok, the standard dialect of Thai. This study examines the current state of tones in the Northern Thai dialect of Chiang Mai, which has six contrastive tones, rather than the five found in Central Thai. This data allows for a comparison to both the Central Thai literature as well as previous studies of Northern Thai, to examine whether Northern Thai is undergoing tone change as well and whether it exhibits similar changes to those reported for Central Thai. Significant exposure to Central Thai via mass media as well as the education system, and widespread bi-dialectalism, may carry the influences of Central Thai tone changes into Northern Thai as well. This study aims to provide further insight into the ongoing changes in the Thai tonal space, in order to clarify the nature of Thai tones today.
The influence of lexical factors on word recognition by native English speakers and Japanese speakers acquiring English: An interim report
Authors: Yoneyama Kiyoko , Munson Benjamin
Published: November 2013

In our earlier work [Yoneyama and Munson, J. Phonet. Soc. Jpn. 14-1 (2010)], we investigated whether neighborhood density and word frequency affect spoken word recognition in English by beginning and advanced Japanese L2 English speakers, and by native English speakers. Our study was modeled after the work of Imai et al. [J. Acoust. Soc. Am. (2005)]. The results indicated that there were strong effects of frequency and neighborhood density on the performance of all three groups of listeners. However, there was no clear evidence for an emerging “neighborhood competition” effect in the Japanese learners of English, contrary to Imai et al. Here we report two additional analyses of these data. The first uses log-linear modeling (i.e., the j-factors in Boothroyd and Nittrouer [J. Acoust. Soc.Am. (1998)]) to examine word recognition in the two groups. The second examines the influence of lexical variables on spoken word recognition response times in L1 and L2 speakers. Preliminary results suggest that the effect of word frequency and neighborhood density on these measures is similar for L1 and L2 speakers of English.
Effects of native language and speech rate on perceptual and decisional processing of voicing and syllable affiliation in stops
Authors: Silbert Noah H. , de Jong Kenneth , Lim Byung-jin , Nagao Kyoko
Published: November 2013

Previous work shows that variation in speech rate influences the perception of voicing distinctions (/b/-/p/) and syllable affiliation (“pea”-“eep”), and it is well-documented that native language influences how listeners perceive phonological distinctions. We analyze the influences of speech rate and native language in the perception of voicing and syllable affiliation by applying a model of perception and response selection to data from Japanese, English, and Korean listeners who identified the voicing and the syllable affiliation of (English) stops produced at slow, moderate, and fast rates. The fitted model indicates that for all three native language groups, perceptual salience decreases substantially as speech rate increases for both voicing and syllable affiliation. Even at slow rates, however, the salience of voicing is lower for coda than for onset stops. In addition, as rate increases, all three groups exhibit an increasing bias toward “onset” responses, with a bias toward “voiced” responses for coda stimuli and toward “voiceless” responses for onset stimuli. Despite broad similarities across all three groups, fine-grained patterns of perceptual salience and response bias vary with listeners’ native language. These data and fitted models illustrate the utility of rate-varied speech in investigations of native language effects in speech perception.
Intonational transfers in second language English speakers
Authors: Robles-Puente Sergio
Published: November 2013

Previous research on Spanish imperatives has demonstrated that their phonetic characteristics may not differ from those of declaratives. However, under the right conditions, imperatives can be produced with up-stepped patterns where nuclear pitch-accents show higher F0 values than pre-nuclear ones. These circumflex configurations are never attested in declaratives (Robles-Puente, 2011). The current study concentrates on the imperatives and declaratives produced by 31 Mexican Spanish/English bilinguals and reveals that this variety of Spanish, unlike Iberian Spanish and English, allows not only imperatives but also declaratives to be produced without the aforesaid intonational constraint. Additionally, the English productions of the same speakers show circumflex configurations indicating a clear prosodic transfer characteristic of their mother tongue. Robles-Puente, Sergio. 2011, “Looking for the Spanish imperative intonation,” in Selected Proceedings of the 5th Conference on Laboratory Approaches to Romance Phonology, edited by S. Alvord, pp. 153–164. Somerville, MA: CPP.
Perception of voicing of English word-final consonants: A comparative study of English listeners and Korean listeners
Authors: Kim Ji Yea
Published: November 2013

This study aims to investigate the perception of word-final consonant voicing. Preceding vowel duration is of interest in comparing the perception of 7 English listeners (EL) and 7 Korean listeners (KL). Each listener was required to listen to 104 stimuli randomly composed of English voiceless and voiced consonants (e.g., “picks” and “pigs”) and to choose from two options what they heard for each of the stimuli. There were 2 types of stimuli: original and manipulated. To manipulate vowel duration, for example, the vowel in the originally voiceless stimulus “picks” was lengthened, whereas the vowel in the voiced stimulus “pigs” was shortened by using Praat. The results show that, in the original stimuli, both groups tend to perceive voicing accurately, but ELs are better than KLs. It is assumed that the lower percentage of KLs’ perception is due to the fact that there is no voicing contrast in Korean. In the manipulated stimuli, however, both groups generally fail to perceive voicing, and the number of stimuli whose voicing was never perceived was greater for ELs than that for KLs. This clearly indicates that ELs rely more on the voicing of following consonants than they do on the preceding vowel length.
The perception of English and Thai fricatives and affricates by Thai learners
Authors: Roengpitya Rungpat -.
Published: November 2013

English has eight voiceless-voiced fricatives /f, v, θ, Ð, s, z, ∫, and ȝ/ and two affricates /t∫ and dȝ/ in all positions. Thai, however, carries only two initial voiceless fricatives /f, s/ and one initial voiceless affricate /t∫/. In the literature, the acoustic cues for fricatives include the frication noise, the amplitude, and the fundamental and formant frequencies on the adjacent vowels. This research explores how Thai listeners can perceive the English fricatives and affricates, as opposed to the Thai set. Thirty-one English and fifteen Thai words with fricatives and affricates were chosen. Two native-American male speakers read all English words, and a native-Thai female speaker read all Thai words. All the words were acoustically measured for the acoustic cues and digitally modified for all 312 tokens with different quality and quantity. Twenty native-Thai listeners (14 females and 6 males) listened and identified each token whether it contained which original fricative or affricate. The results revealed that the correct responses of the Thai learners were at a higher rate (90–100%) for the Thai original and modified tokens, and at a lower rate (30–100%) for the English set. It is hoped that this study will shed light on to future perceptual studies.
Comparison of perceptual training and production training on tone identification
Authors: Lu Shuang , Wayland Ratree , Kaan Edith
Published: November 2013

Previous studies have shown that short-term perceptual and production training can improve the comprehension and production of lexical tones by non-tone language speakers (e.g., Wang et al., 1999; Leather, 1990). The current study compared the effectiveness of an identification-only training and an identification-plus-imitation training on lexical tone perception. Stimuli consisted of 12 monosyllables associated with three linear tones that resemble the level, rising and falling tones in Mandarin Chinese. Twenty participants first did a baseline identification task, and then received either an identification-only or an identification-plus-imitation training. The trainings were exactly the same except that the identification-plus-imitation training required participants to imitate the stimuli, while the identification-only training had participants utter the tone types of the stimuli (i.e., level, rising or falling). Lastly, all participants did the same baseline identification task again. The tone identification accuracy improved in both the identification-only and the identification-plus-imitation groups after training. Moreover, the identification-plus-imitation group identified the tones more quickly in the post-training task than in the pre-training task while the identification-only group did not show any improvement. These results indicated that the identification-plus-imitation training was more effective to improve the tone identification than the identification-only training.
Adding thermal and granularity effects to the effective density fluid model
Authors: Williams Kevin
Published: November 2013

Previously, an effective density fluid model (EDFM) was developed for unconsolidated granular sediments and applied to sand. The model is a simplification of the full Biot porous media model. Here two additional effects are added to the EDFM model: heat transfer between the liquid and solid at low frequencies and the granularity of the medium at high frequencies. The frequency range studied is 100 Hz–1 MHz. The analytical sound speed and attenuation expressions obtained have no free parameters. The resulting model is compared to ocean data.
Hybrid geoacoustic inversion scheme with an equivalent seabed model
Authors: Li Zhenglin , Zhang Renhe
Published: November 2013

Acoustic propagation in shallow water is greatly influenced by the properties of the bottom. The purpose of geoacoustic inversion is estimation of ocean bottom acoustic parameters such as sediment sound speeds, densities, and attenuations from measured acoustic fields. Especially, geoacoustic inversion could give low frequency attenuation, which cannot be measured by coring the sediment. Therefore, it has been paid much attention in recent years. A hybrid geoacoustic inversion scheme, which combines several inversion methods together to invert for the bottom parameters, has been proposed based on the fact that the bottom acoustic parameters have different sensitivities to the different physical parameters of acoustic field. This inversion scheme could avoid the problem of the multiple solutions, which are often companied with some geoacoustic inversion methods. The validity of the inversion scheme is verified in a series of sea experiments at different sites. In the experiment, six different sediment types: Fine Sand, Silty Sand, Sand Silty, Sand-Silty-Clay, Silty Clay and Mud, are included in an area in the Yellow Sea. The inverted bottom parameters could distinguish the atlas marked bottom type quite well. [Work supported by the National Natural Science Foundation of China under Grant Nos. 11074269 and 10734100.]
In situ measurements of sediment sound speed in the frequency band of 2–10 kHz at target and reverberation experiment site
Authors: Yang Jie , Tang Dajun
Published: November 2013

As part of the environmental measurements for TREX13 (Target and Reverberation EXperiment 2013), in situ measurements of surfacial sediment sound speed were carried out off Panama City, Florida, using a system called Sediment Acoustic-speed Measurement System (SAMS). SAMS consists of ten fixed sources positioned just above the seafloor, and one receiver which is driven into the seabed to a known depth. During TREX13, 10 deployments were made along the main reverberation track which is about 7.5 km in length. All measurements were made at a penetration depth of 3m between 2 to 50 kHz, focusing on 2–10 kHz. Preliminary sediment sound speed results show variation from low sound speeds (muddy sites) to high sound speeds (sandy sites). A 3–5% of dispersion was observed at coarse sandy sites between 2 and 10 kHz, whereas little dispersion was observed at muddy sites. [Work supported by ONR.]
Estimates of sediment volume heterogeneity spectra from several distinct shallow water locations
Authors: Holland Charles W.
Published: November 2013

Theory indicates that sediment volume heterogeneities tend to dominate seabed scattering above the critical angle. However, recent evidence indicates that scattering from volume heterogeneities can also be the dominant mechanism below the critical angle. This raises questions about the nature and scales of volume heterogeneities in marine sediments. Direct measurements of sediment heterogeneities have been performed on cores using for example x-ray CT scans, however this and related methods only sample a very small volume. In this paper, a method is presented for estimating sediment heterogeneity spectra from acoustic reverberation data where the sediment volume probed is order 107 m3. The large averaging volume permits measuring a wide range of spatial frequencies and tends to emphasize persistent scales. Resulting sediment volume spectra from several different shallow water regions will be presented. [Research sponsored by the ONR Ocean Acoustics.]
Layer-Resolved Graphene Transfer via Engineered Strain Layers
Authors: Kim Jeehwan , Park Hongsik , Hannon James B. , Bedell Stephen W. , Fogel Keith , Sadana Devendra K. , Dimitrakopoulos Christos
Published: November 2013

Monolayer Graphene via Two Transfers

Oriented monolayers of graphene containing some bilayer regions can be formed on silicon carbide crystal surfaces, but, to be cost effective, the graphene needs to be exfoliated and transferred to other substrates so that the silicon carbide crystal can be reused.

Kim
et al.

(p.
833
, published online 31 October) used a nickel film grown to a thickness designed to impart a particular surface stress as a “handle” to exfoliate the graphene layer for transfer to a silica substrate. An additional gold layer was then used to remove the excess monolayer from the bilayer regions to create a monolayer suitable for electronics applications.
Complete Genome Sequence of the Last Representative Genotype of Wild Indigenous Poliovirus Type 1, Which Circulated in Brazil
Authors: Tavares Fernando N. , da Costa Eliane V. , Kew Olen M. , da Silva Edson E.
Published: November 2013

Polioviruses are the major etiological agents associated with acute flaccid paralysis (AFP). The complete genome sequence of a representative of the last wild poliovirus type 1 genotype isolated in Brazil from a paralytic poliomyelitis case is reported here.
Draft Genome Sequence of Pseudomonas azotifigens Strain DSM 17556T(6H33bT), a Nitrogen Fixer Strain Isolated from a Compost Pile
Authors: Busquets Antonio , Peña Arantxa , Gomila Margarita , Mulet Magdalena , Mayol Joan , García-Valdés Elena , Bennasar Antonio , Huntemann Marcel , Han James , Chen I-Min , Mavromatis Konstantinos , Markowitz Victor , Palaniappan Krishnaveni , Ivanova Natalia , Schaumberg Andrew , Pati Amrita , Reddy T. B. K. , Nordberg Henrik , Woyke Tanja , Klenk Hans-Peter , Kyrpides Nikos , Lalucat Jorge
Published: November 2013

Pseudomonas azotifigensstrain 6H33bTis a nitrogen fixer isolated from a hyperthermal compost pile in 2005 by Hatayama and collaborators. Here we report the draft genome, which has an estimated size of 5.0 Mb, exhibits an average G+C content of 66.73%, and is predicted to encode 4,536 protein-coding genes and 100 RNA genes.
Complete Genome Sequence of Ralstonia pickettii DTP0602, a 2,4,6-Trichlorophenol Degrader
Authors: Ohtsubo Yoshiyuki , Fujita Nobuyuki , Nagata Yuji , Tsuda Masataka , Iwasaki Tomohiro , Hatta Takashi
Published: November 2013

Ralstonia pickettii
strain DTP0602 utilizes 2,4,6-trichlorophenol as its sole carbon and energy source. Here, we report the complete genome sequence of strain DTP0602, which comprises three chromosomes and no plasmids. We also found that the two
had
gene clusters responsible for the degradation of 2,4,6-trichlorophenol are located on the 2.9-Mb chromosome 2.
Draft Genome Sequence of the Antibiotic-Producing Cystic Fibrosis Isolate Pantoea agglomerans Tx10
Authors: Smith Derek D. N. , Kirzinger Morgan W. B. , Stavrinides John
Published: November 2013

Pantoea agglomerans
is an enteric bacterium that is capable of causing both plant and human disease. Here, we report the genome sequence of a cystic fibrosis isolate,
P. agglomerans
Tx10, which produces an antibiotic that is effective against
Staphylococcus aureus
.
The trends and the risk of type 1 diabetes over the past 40 years: an analysis by birth cohorts and by parental migration background in Sweden
Authors: Hussen Hozan Ismael , Persson Martina , Moradi Tahereh
Published: November 2013

Objective

To investigate the trends and the risk of developing type 1 diabetes in the offspring of Swedes and immigrants by specific parental migration background, age, sex and birth cohort.

Design

Registry-based cohort study.

Setting

Using Swedish nationwide data we analysed the risk of developing type 1 diabetes in 3 457 486 female and 3 641 304 male offspring between 0 and 30 years of age, born to native Swedes or immigrants and born and living in Sweden between 1969 and 2009. We estimated incidence rate ratios (IRRs) with 95% CIs using Poisson regression models. We further calculated age-standardised rates (ASRs) of type 1 diabetes, using the world population as standard.

Results

We observed a trend of increasing ASRs among offspring below 15 years of age born to native Swedes and a less evident increase among offspring of immigrants. We further observed a shift towards a younger age at diagnosis in younger birth cohorts in both groups of offspring.Compared with offspring of Swedes, children (0–14 years) and young adults (15–30 years) with one parent born abroad had an overall 30% and 15–20% lower IRR, respectively, after multivariable adjustment. The reduction in IRR was even greater among offspring of immigrants if both parents were born abroad. Analysis by specific parental region of birth revealed a 45–60% higher IRR among male and female offspring aged 0–30 years of Eastern Africa.

Conclusions

Parental country of birth and early exposures to environmental factors play an important role in the aetiology of type 1 diabetes.
Adherence to antiretroviral drug therapy in adult patients who are HIV-positive in Northwest Ethiopia: a study protocol
Authors: Bezabhe Woldesellassie M , Peterson Gregory M , Bereznicki Luke , Chalmers Leanne , Gee Peter
Published: November 2013

Introduction

Achievement of optimal medication adherence and management of antiretroviral toxicity pose great challenges among Ethiopian patients with HIV/AIDS. There is currently a lack of long-term follow-up studies that identify the barriers to, and facilitators of, adherence to antiretroviral therapy (ART) in the Ethiopian setting. Therefore, we aim to investigate the level of adherence to ART and a wide range of potential influencing factors, including adverse drug reactions occurring with ART.

Methods and analysis

We are conducting a 1-year prospective cohort study involving adult patients with HIV/AIDS starting on ART between December 2012 and March 2013. Data are being collected on patients’ appointment dates in the ART clinics. Adherence to ART is being measured using pill count, medication possession ratio and patient's self-report. The primary outcome of the study will be the proportion of patients who are adherent to their ART regimen at 3, 6 and 12 months using pill count. Taking 95% or more of the dispensed ART regimen using pill count at given points of time will be considered the optimal level of adherence in this study. Data will be analysed using descriptive and inferential statistical procedures.

Ethics and dissemination

Ethics approval was obtained from the Tasmania Health and Medical Human Research Ethics Committee and Bahir-Dar University's Ethics Committee. The results of the study will be reported in peer-reviewed scientific journals, conferences and seminar presentations.
Estimation of net muscle volume in patients with muscular dystrophy using muscle CT for prospective muscle volume analysis: an observational study
Authors: Nakayama T , Kuru S , Okura M , Motoyoshi Y , Kawai M
Published: November 2013

Objectives

Muscle volume in patients with muscle disease is an index of disease progression. The aim of this study was to demonstrate a new method of muscle volumetry using CT of thigh muscles.

Design

Observational study.

Participants

(1) For muscle volumetry using CT and dual-energy X-ray absorptiometry (DXA), 13 patients with muscle disease participated. (2) For prospective CT volumetry, 12 patients participated over 4 years.

Primary and secondary outcome measures

To establish the new CT volumetry, the results of which were correlated with the muscle mass calculated from DXA (primary outcome). To show the decrease in muscle volume using our method over 4 years (secondary outcome)

Methods

(1) Helical CT imaging of the thigh was performed. CT images were analysed by applying estimated functions, and the accumulation of outcomes resulted in muscle volumes. We refer to this method as ‘net muscle volumetry’. Simultaneously, DXA was performed in these patients, and the muscle mass of the thigh was calculated with vendor-provided software. (2) To evaluate longitudinal changes in muscle volume, net muscle volumetry at the 14 cm section of the middle part of the thigh was performed repeatedly over a 4-year period.

Results

(1) Volumes of the thigh muscle on one side were calculated to be 300–3400 cm3using CT. Muscle mass of the thigh was calculated from DXA to be 1100–5000 g. These results correspond closely, with a Pearson correlation coefficient of 0.993. (2) Thigh net muscle volumes of seven patients with gait disturbance decreased over the 4-year study period (p<0.01).

Conclusions

A method of measuring net muscle volume using CT, which was validated by muscle mass calculated from DXA, was developed. Decrements in net muscle volume over 4 years support the reliability of this method. This less arbitrary method is suitable for assessment of muscle volume in patients with muscular dystrophy.
ACTION WITH ACCELERATION II: EUCLIDEAN HAMILTONIAN AND JORDAN BLOCKS
Authors: BAAQUIE BELAL E.
Published: November 2013

The Euclidean action with acceleration has been analyzed in Ref. 1, and referred to henceforth as Paper I, for its Hamiltonian and path integral. In this paper, the state space of the Hamiltonian is analyzed for the case when it is pseudo-Hermitian (equivalent to a Hermitian Hamiltonian), as well as the case when it is inequivalent. The propagator is computed using both creation and destruction operators as well as the path integral. A state space calculation of the propagator shows the crucial role played by the dual state vectors that yields a result impossible to obtain from a Hermitian Hamiltonian. When it is not pseudo-Hermitian, the Hamiltonian is shown to be a direct sum of Jordan blocks.
CARBON PRECURSOR DEPENDENCE OF CARBON NANOFIBERS SYNTHESIZED BY CATALYST-FREE ULTRASONIC SPRAY-PYROLYSIS METHOD
Authors: BAO JIANFENG , KISHI NAOKI , SOGA TETSUO
Published: November 2013

In this paper, we report the growth of carbon nanofibers (CNFs) by catalyst-free ultrasonic spray-pyrolysis of methanol, ethanol and 2-propanol. We found that the morphology of carbon deposition on the substrate strongly depended on the position of the substrate in the reaction tube and the carbon source species. When ethanol and 2-propanol were used as the carbon source, a slightly hollow structure CNFs were formed downstream in the reaction tube, whereas when the carbon source was methanol, an amorphous structure CNFs were formed at the center of the reaction tube. We consider the difference in CNFs growth between the alcohol types is presence of alkyl groups in alcohol.