bluuebunny/crossref_metadata_2025 huggingface dataset:
Soundscape analysis and acoustical design strategies for an urban village development
Authors: Kwon Youngmin , Smitthakorn Pattra , Siebein Gary W.
Published: October 2013

Overall establishment of an acoustical landscape (soundscape) would be the fundamental source of sonic information that is useful in initiating urban design and planning strategies. A soundscape analysis was conducted in conjunction with an urban transportation and community design project targeting the western section of Gainesville, FL. The community was acoustically characterized and analyzed by means of quantitative measurements and qualitative assessments by observation. The measurements included instantaneous, 1-min short-term and 24-h long-term measurements. The parameters involved in these measurements are A-weighted average Lp, Leq, Lmax, Lmin, and LDN. The overall sonic environment of the community as well as the types of sounds that are desirable and noises that are not desireble in the existing and future contexts were identified. The results showed that the community was dominated mostly by traffic noise from several major thoroughfares and by occasional fire alarm noise. Finally, methods or strategies to reduce, buffer, and mitigate the undesirable sounds and to preserve the desirable sounds were suggested. The addition of new characteristics to the soundscape, such as people activity sounds and ‘‘natural’’ sounds, were also proposed. The application of acoustical urban design strategies to the specifically proposed urban transportation design plans was further analyzed.
Tabu inversion in the East China Sea
Authors: Michalopoulou Zoi-Heleni , Miller James H. , Potty Gopu R.
Published: October 2013

Tabu, a global optimization method that exploits search history to explore the parameter space in a structured manner, has been shown to perform well in geoacoustic inversion with both real and synthetic data. To investigate the efficacy and adaptability of Tabu search to various ocean environments, we conducted Tabu inversion for broadband data (at frequencies between 20 and 600 Hz) collected in the East China Sea during the ASIAEX experiment. A simple incoherent Bartlett objective function was considered. Localization results and geoacoustic estimates obtained via Tabu closely match ground truth information and parameter estimates obtained with other inversion methods. Appropriate hierarchical ordering of the unknown parameters ensured identification of the global maximum of the objective function within only a few forward model calculations. [Work supported by ONR.]
Mode studies in a triangular bell plate
Authors: Hansen Uwe J. , Garner James , Rossing Thomas D. , Hogg Suzanne
Published: October 2013

A triangular bell plate serves as a poor man’s hand bell. A clapper affixed to the handle strikes the plate, resulting in a sound somewhat resembling the tone of a hand bell. A similar arrangement has been used with slotted Eames tubes. This paper will present a comparison of modes of vibration of a triangular bell plate as observed with holographic interferometry, modal analysis, and as calculated using finite element methods. The holographic interferometry studies were done in the Acoustics laboratory of NIU, the modal analysis work was carried out at ISU, and the FE calculations were done at the UT in Sydney. The similarity of mode shapes and mode frequencies lends credence to the validity of the techniques.
Simulation of fluid flow in and around a porous windscreen
Authors: Wilson D. Keith , White Michael J.
Published: October 2013

Fluid dynamic simulation of wind noise (turbulent pressure fluctuations) around porous microphone windscreens in an atmospheric flow is made difficult by the broad range of spatial scales, from large atmospheric eddies down to the pore size of the windscreen, that is involved. Here, we describe a simplified simulation approach that is based on two new insights: (1) the ability of linear fluid flow approximations to describe wind noise [Z.C. Zheng and B. K. Tan, J. Acoust. Soc. Am. 113, 161–166 (2003)] and (2) a new set of macroscopic, time-domain relaxational equations for the linear interaction of a fluid flow with a porous material [D. K. Wilson, V. E. Ostashev, and S. L. Collier, J. Acoust. Soc. Am. 116, 1889–1892 (2004)]. An upstream flow condition consisting of quasiwavelets (analogous to turbulent eddies) is also used to create well-developed, realistic turbulence. This simulation approach is shown to provide detailed simulations of the production of pressure fluctuations in and around a porous windscreen.
The sense of hearing mediated by the saccule in goldfish
Authors: Fay Richard R.
Published: October 2013

The saccule mediates the sense of hearing for many fish species, goldfish (Carassius auratus) in particular. Motions of the swim bladder in response to pressure fluctuations impinge on the saccule of each ear, where auditory-nerve fibers project to medullar, midbrain, and forebrain nuclei in a circuit analogous to the ascending auditory system of tetrapods. It has been repeatedly shown over the past 40 years that the sense of hearing mediated by the saccule has many fundamental features in common with the sense of hearing of tetrapods. Detection and discrimination thresholds for goldfish are in the vertebrate range quantitatively, and are of the same sorts of simple and complex discriminations that mammals and other tetrapods can perform. Furthermore, goldfish behave as if the perceptual dimensions of spectral pitch, complex musical pitch, timbre, and roughness exist for them. Although goldfish do not vocalize, many fish species that hear using saccular input do vocalize (e.g., mormyrids), and have special adaptations for responding to vocalizations, like many tetrapods. Finally, goldfish have been shown capable of simultaneous stream segregation based on the same principles known for humans and other species. Thus, otolith organs can participate in a sense of hearing that is typical for vertebrates.
Quantitative ultrasound techniques
Authors: Hall Timothy , Zagzebski James , Madsen Ernest
Published: October 2013

The ultrasound research group at UW-Madison has been pursuing quantitative measurement of the acoustic properties of tissues for more than three decades. Much of that effort parallels the efforts pioneered by Fred Lizzi and colleagues at Riverside Research Institute (RRI). While the RRI group was blazing trails in data acquisition, analysis, and interpretation techniques, the UW group was investigating the limits of measurement accuracy using similar approaches. Wise selection of the tissues to investigate, great intuition regarding fruitful paths, and good hard work resulted in substantial progress and success in the RRI quantitative ultrasound efforts. Careful measurements with high-quality phantoms, in parallel with tissue measurements, resulted in substantial progress in determining limits on quantitative ultrasound measurement accuracy under various experimental conditions. This presentation will highlight some of the differences and similarities in the approaches to quantitative ultrasound by these two groups and how we can use that information in future investigation.
Anthropogenic sound—Introduction and overview of the ambient and anthropogenic environment
Authors: Popper Arthur N. , Fay Richard R.
Published: October 2013

Interest in anthropogenic sound in the marine environment has been directed at concerns about the effects of sound on marine mammals. However, fish make up a far larger and more diverse portion of the oceans than do marine mammals, and they hold considerable economic importance internationally. This has led to a growing interest in the effect of anthropogenic sounds on fish in environments ranging from shallow waters near in-shore shipping lanes to the deep sea. Concerns for effects on fish are parallel to those for marine mammals, and include issues ranging from the death of individual animals to the potential for behavioral changes that could lead to impacts on the survival of populations or species. While the body of data on the effects of anthropogenic sounds on fish is still small, and much of the work is not in the peer-reviewed literature, the number of peer-reviewed studies is growing. The purpose of this special session is to provide an overview of what we currently know about the effects of anthropogenic sound on fish, help define the major outstanding questions on these effects, and to provide the basis for discussion of current and future research in order to help resolve these questions.
Structure/function relationships in the saccule of fishes
Authors: Popper Arthur N. , Deng Xiaohong , Zeddies David , Hastings Mardi C.
Published: October 2013

The saccule is morphologically the most diverse of the otolithic end organs among fish. Each otolithic end organ contains a sensory epithelium with numerous hair cells. The apical ends of the hair cell ciliary bundles contact a solid dense otolith. Relative motion between the sensory epithelium and otolith results in stimulation of the hair cells. Diversity in the saccule includes the overall shape and size of the end organ, the number of hair cells, the length of the ciliary bundles, and the shape and size of the otolith. Functionally, the saccule subserves both hearing and vestibular senses. There is some correlation between the orientation pattern of the sensory hair cells with whether fish are specialized for hearing or not. Yet, there is no real understanding of the relationship between structural diversity and functional differences. In effect, it is not known whether the structural diversity indicates adaptations for different auditory and/or vestibular functions, or whether the structural diversity reflects different ways for taxonomically and ecologically diverse fish to do similar ear functions. This talk will explore these issues using data from highly diverse deep-sea fish and direct measures of responses of the inner ear to sound.
Finite-difference time-domain simulation of acoustic propagation through a dispersive oceanic bubble cloud
Authors: Norton Guy
Published: October 2013

Accurate modeling of pulse propagation and scattering is a problem in many disciplines. For the case of an acoustic wave propagating in a two-dimensional non dispersive medium, a routine second-order in time and space finite-difference-time-domain (FDTD) scheme representation of the linear wave equation can be used to solve for the acoustic pressure. However, when the medium is dispersive, one is required to take into account the frequency-dependent attenuation and phase speed. Until recently, to include the dispersive effects one typically solved the problem in the frequency domain and then Fourier transformed into the time domain. However, by using a theory proposed by Blackstock [D. T. Blackstock, J. Acoust. Soc. Am. 77, 2050 (1985)], the linear wave equation has been modified by adding an additional term that takes into account the dispersive nature of the medium. In this work a fourth-order (in time and space) 2-D FDTD scheme, which includes attenuation and dispersion via the convolution operator, is used to model backscattering of broadband signals from a dispersive composite subsurface bubble cloud composed of two different plumes underlying a random rough sea surface. [Work supported by ONR/NRL.]
Sound waves and shear waves in sediments
Authors: Buckingham Michael J.
Published: October 2013

In a long and illustrious career, Joe Blue made many significant contributions to the discipline of underwater acoustics, although he is probably best known for his work on the design and calibration of hydrophones and hydrophone arrays. Such instrumentation has many applications, including measurements of the geoacoustic properties of marine sediments. In this paper, recent developments on the properties of sound waves and shear waves in sediments will be summarized and certain difficulties that are encountered when attempts are made to match theory to data will be highlighted. Central to the discussion are the compressional-wave and shear-wave dispersion relations, that is, phase speed and attenuation as functions of frequency. In a saturated sediment, the phase speeds and attenuations also depend on various physical properties, for example, the porosity, density, grain size, and overburden pressure (depth). These dependencies will be illustrated using extensive data sets taken from the literature. Any satisfactory theory of waves in sediments must yield correctly not only the dispersion relations but also all the dependencies on the physical properties. A recently developed theory that satisfies these criteria will be discussed in the context of the available data. [Research supported by ONR.]
Bayesian geoacoustic inversion of time-averaged horizontal-array data
Authors: Dosso Stan E. , Tollefsen Dag
Published: October 2013

This paper considers quantifying data errors in Bayesian geoacoustic inversion applied to time-averaged data. Cross-spectral density matrices are formed by averaging spectra from a sequence of time-series segments (data snapshots). Error estimation for snapshot-averaged data has typically assumed either that averaging reduces errors as if they are fully independent between snapshots (an optimistic assumption), or that averaging does not reduce errors at all (a pessimistic assumption). Data errors are quantified here assuming that averaging reduces measurement error (dominated by ambient noise, which can be reasonably assumed independent), but does not reduce theory (modeling) error. This provides a physically reasonable intermediate result between the optimistic and pessimistic assumptions. Bayesian inversion is applied to data collected by FFI with a bottom-mounted horizontal array at a shallow-water site in the Barents Sea. Supporting geophysical measurements (seismic reflection and refraction, bottom-penetrating sonar, gravity core) provide independent information on seabed properties. A towed acoustic source transmitted multiple low-frequency tones at levels comparable to those of a merchant ship. Inversion results in the form of marginal posterior probability distributions are compared for the different approaches to data error estimation, and for data collected for several source ranges and bearings.
Selective modal excitation using phase-shifted ultrasound radiation force
Authors: Huber Thomas M. , Fatemi Mostafa , Kinnick Randall R. , Greenleaf James F.
Published: October 2013

The ultrasound radiation force can be used as a noncontact method for exciting vibrational modes. In one implementation, an audio-range modulation signal is combined with a 40-kHz carrier to form a double-sideband suppressed-carrier (DSSC) waveform that is emitted from an ultrasound transducer. The frequency of the ultrasound radiation force is the difference between the frequencies of the sidebands, therefore at twice the modulation frequency. We describe a method for selective mode excitation using a transducer pair, each emitting a DSSC signal. The modulation signal for one transducer was phase shifted relative to the other transducer. When the two modulation signals were in phase, the radiation stress field was uniform. For devices studied, this excited transverse modes while suppressing torsional modes. Similarly, if the modulation signals were out of phase, torsional modes were excited while suppressing transverse modes. This technique has been demonstrated for devices including an MEMS mirror, hard-drive suspension, and brass cantilever. For a cantilever, the ratio of the amplitudes of 180-Hz transverse over 1.3-kHz torsional modes was varied by over two orders of magnitude by shifting the phase difference between the two beams over a range of 90 deg. This noncontact technique allows control over the types of vibration excited.
Vowel production with and without auditory feedback in children with cochlear implants
Authors: Bharadwaj Sneha V. , Graves Amanda G.
Published: October 2013

The effects of auditory feedback on vowel formant frequencies were investigated in the speech produced by three early-implanted (received cochlear implants before the age of 3 years) and three late-implanted children (after 5 years). The syllables /heed/, /hid/, /had/, /whod/, /hood/, and /hod/ were produced in a carrier sentence 12 times, each in both implant processor ON (auditory feedback present) and OFF (feedback absent) conditions. Comparisons of the vowel formant frequencies in processor ON versus OFF conditions revealed primarily second formant frequency (F2) shifts for a majority of the vowels, while showing minimal changes in the first formant frequencies (F1). In addition, a majority of the F2 shifts was towards the middle of the vowel space, suggesting centralization of vowels in the absence of auditory feedback. Further, most of the formant frequency changes were present in the vowels produced by late- compared to early-implanted children. These findings suggest that the late-implanted children may rely on auditory feedback to a greater extent than early-implanted children for speech production. Implications of the short-term effects of auditory feedback on speech production will be discussed in reference to the feedback and feed-forward models for speech production. [Work supported by NIH/NIDCD R03DC007052-01.]
Using the reassigned spectrogram to obtain a voiceprint
Authors: Fulop Sean A. , Fitz Kelly
Published: October 2013

While established methods for imaging the time-frequency content of speech—such as the spectrogram—have frequently been christened ‘‘voiceprinting,’’ it is well-known that it and other currently popular imaging techniques cannot identify an individual’s voice to more than a suggestive extent. The reassigned spectrogram (also known by other names) is a relatively little-known method [S. A. Fulop and K. Fitz, ‘‘Algorithms for computing the time-corrected instantaneous frequency (reassigned) spectrogram, with applications,’’ J. Acoust. Soc. Am. 119, 360–377 (2006)] for imaging the time-frequency spectral information contained in a signal, which is able to show the instantaneous frequencies of signal components as well as the occurrence of impulses with dramatically increased precision compared to the spectrogram (magnitude of the short-time Fourier transform) or any other energy density time-frequency representation. It is shown here that it is possible to obtain a reassigned spectrogram image from a person’s voice that appears to be sufficiently individuating and consistent so as to serve as a true voiceprint identifying that person and excluding all other persons to a high degree of confidence. This is achieved by focusing on just a few phonatory pulsations, thereby revealing the vocal-fold vibrational signature unique to each person.
Evanescent time reversal: Super-resolution and communications applications
Authors: Conti Stephane G. , Roux Philippe , Kuperman William A.
Published: October 2013

The spatial resolution of the focused field with a classical time-reversal mirror in the far field has a wavelength-order diffraction limit. Previously reported results for super-resolution beyond the diffraction limit require either the full knowledge of the original source, or the evanescent waves in the near field. Here, we show that subwavelength focusing can be achieved without a priori knowledge of the original probe source. In the wave-number domain, the contributions for the spatial localization and for the resolution of the focus can be separated from each other in the time-reversed field recorded within one wavelength of the original source. The evanescent time-reversal field is then obtained from the combination of the spatial localization contribution from the far-field time reversed with the spatial resolution for a point source. Further, we show that different signals can be transmitted simultaneously with subwavelength separation. Super-resolution of the order of 1/20 of the wavelength is experimentally demonstrated with acoustic wave fields. Applications for communications are presented using multiple receivers a fraction of the wavelength apart.
Acoustical characteristics of muddy sediments.
Authors: Carey William M. , Pierce Allan D.
Published: October 2013

Muddy sediments found in rivers, deltas, and harbors are classified as slow bottoms and pose a problem for the detection of buried ordnance. The questions for mud discussed here are as follows: First, can the frequency dependence dispersion characteristic be predicted and verified by measurements in areas where buried object detection is required? Second, what is the optimum yet simplest method of calculating sound scattering from buried compact but complex shaped objects? Wood and Weston [Acustica, V14, (1964)] indicated that muddy sediments have a compressional speed 3% less than that of water with a linear frequency dependent attenuation (less than that of sand) in the kilohertz range. This paper reviews experiments performed on muddy sediments at frequencies greater than a kilohertz and compares them to recent experimental measurements in pond sediments. The importance of gas content and bubbles is discussed. Gas content and bubbles are shown to be important factors in the reverberation from these slow bottoms. A theoretical treatment of “muddy sediments” is used to estimate the dispersion characteristic mud and to place limits on the use of sonar to find buried objects such as unexploded ordnance in the presence of reverberation due to gaseous inclusions. [Work sponsored by the Strategic Environmental Research and Development Program.]
Is that “acoustic?” Unexpected finishes used to shape the acoustic environment.
Authors: Miller Gregory , Way Evelyn , Harrison Byron , Talaske Richard
Published: October 2013

The visual aesthetic desired by many contemporary architects includes surfaces that are incompatible with acoustic requirements for sound absorption and sound diffusion—particularly concave walls and large expanses of smooth, flat surfaces. Additionally, the necessity of sustainable design requires the creative use (and reuse) of unexpected construction materials. Case studies to be presented include the Jewish Reconstructionist Congregation of Evanston, Illinois, the Arena Stage in Washington, DC, The Harman Center for the Arts in Washington, DC, the Steppenwolf Theater in Chicago, Illinois, and the North Campus Auditorium at the Walgreen Drama Center of the University of Michigan at Ann Arbor. These projects will be used to highlight the use of woven textures, shaped precast, and poured-in-place concrete, screens, and repurposed construction waste to solve common (and some uncommon) acoustic challenges.
Recording studio rehabilitation.
Authors: Long Marshall
Published: October 2013

From time to time projects are designed and built, which do not perform in the expected manner. Sometimes outside events interfere with the design intent. In other cases there is a fundamental misunderstanding of the technical principles involved. This is an example of one of these cases. A recording studio was designed (by a well known studio designer, who shall remain nameless) and built on the first floor of a multistory high rise in Los Angeles, CA. It consisted of a studio approximately 20×18×10 ft3 high and an adjacent control room. A 3-in. concrete floor was isolated on 1/2-in. rubber and the walls and ceiling were built independently on top of the floor. After completion both footfall and carts being pushed along a corridor approximately 15 ft away were clearly audible inside the studio. This paper describes the steps taken to analyze and correct the problem.
On the exponential power law for low frequency attenuation in shallow water.
Authors: Carey William M.
Published: October 2013

A review of measured transmission over sandy bottoms has found the attenuation α(f)=α(fo)⋅(f/fo)n, 1.6≤n≤1.87 for 50 Hz<f<1 kHz where the reference frequency fo is nominally 1 kHz. Since plausible theory suggests that n should be equal to 2, why are observed n values different? Calculations incorporating scattering, layering, and gradients were found not to explain this observation. The discrepancy can be explained when an additional attenuation mechanism (generated lower velocity shear waves carry energy out of the waveguide) is considered. Since the intrinsic attenuation, αi(f), and the apparent attenuation due to shear wave conversion, αswc(f), are small, the observed attenuation can be α(f)≈αswc(f)+αi(f). If the removal of energy by shear wave conversion is comparable to the intrinsic attenuation at the lower frequencies but less than the intrinsic attenuation at the higher frequencies, the inferred frequency dependence can be less than quadratic. Inversions with fluid sediments account for this effect by the use of a site-specific n factor that accounts for the loss of energy from the compressible field due to shear wave conversion. Furthermore the knowledge of cs(f,z) is required and may necessitate new methods to measure this property of sediments.
The physical mechanism (viscosity related) of low-frequency acoustic wave attenuation in sandy/silty sediments.
Authors: Pierce Allan D.
Published: October 2013

Considered saturated sediments contain diverse rock pebbles (characteristic size of 0.1 mm). The weight of higher pebbles holds lower pebbles in contact sufficiently that acoustically induced solid displacements vary slowly over several adjacent pebbles. Apart from contact areas, each is nearly surrounded by water at a nearly uniform pressure. An appropriate first approximation predicts that the elastic stress tensor in the pebbles is diagonal, with components equal to the negative of the acoustic pressure in the neighboring fluid. The assumptions of Mallock and Wood apply: the mass weighted local average velocity is proportional to the negative gradient of the pressure in the water. The no-slip condition at the interfaces tends to force the water to move with the pebbles, but the finite viscosity allows the fluid at small distances from the interfaces to move at a different velocity than the pebbles. The apparent driving force for the oscillations of the interstitial water relative to the pebbles is associated with the inertia of the water and is proportional to the difference in densities. The derived approximate wave equation predicts attenuation proportional to frequency squared, proportional to the square of the difference of the densities, and inversely proportional to viscosity. The derived dimensionless proportionality constant is consistent with recent experiments.
The amount of information needed for listeners to detect a foreign accent.
Authors: Park Hanyong , de Jong Kenneth , Darcy Isabelle
Published: October 2013

This study examined how much information is needed for listeners to detect a foreign accent. Two factors were considered regarding the amount of information: stimulus length and L1 phonotactics. Four Korean-English bilinguals and two native speakers of American English produced different lengths, but still short stimuli: the vowel /ɑ/, monosyllabic and disyllabic English words. The monosyllabic corpus, in particular, included the stimuli having both natural (i.e., CV) and unnatural syllable structures (i.e., CCV, CVC, and CCVC) as well as various segments in terms of Korean phonotatics. After being presented with a stimulus, eight native listeners were asked to judge whether the speaker of the stimulus was a native or a non-native speakers of American English. The examination of d′ value indicates that all the listeners detected a foreign accent from hearing the monosyllabic and disyllabic stimuli, but only some listeners did from hearing the vowel /ɑ/. Furthermore, the listeners detected a foreign accent more often from the stimuli having the coda segment. Lastly, d′ values for the stimuli having /l/ were lower than those for other stimuli. All these suggest that listeners may not need much information to detect a foreign accent, which, in turn, is closely related to L1 phonotactics.
Annular-array 35-MHz chirp imaging applied to biomedical studies.
Authors: Mamou Jonathan , Aristizábal Orlando , Ketterling Jeffrey A. , Silverman Ronald H. , Turnbull Daniel H.
Published: October 2013

High-frequency ultrasound (HFU) is an attractive means of obtaining fine-resolution images of biological tissues for ophthalmologic, dermatological, and small-animal applications. Nevertheless, even with current improvements in circuit designs and high-frequency equipment, HFU suffers from two limitations. First, HFU images have a limited depth-of-field (DOF) because of the short wavelength and the low-fixed F-number of HFU transducers. Second, HFU is usually limited to shallow imaging because of significant attenuation in tissues. Previously, a 17-MHz five-element annular array was excited using chirp-coded signals and a synthetic-focusing algorithm was used to form images. Results demonstrated significant increase in DOF and penetration depth. In the present study, the same approach was implemented with 35-MHz five-element annular arrays. Vitreous-hemorrhage-mimicking phantom was imaged. Chirp images of a phantom showed increased sensitivity compared to conventional monocycle images and blood droplets into the phantom could be visualized 4 mm deeper. Three-dimensional datasets of 12.5-day-old-mouse-embryo heads were also acquired in utero using chirp and conventional excitations. Synthetically focused images were formed and the brain ventricles were segmented and reconstructed in three dimensions. Significant artifacts for the ventricle volumes were observed with the conventional imaging technique but were not apparent on the chirp-based dataset reconstruction. [Work supported by NIH Grant No. EB006509.]
Pulse coding for a new scanning bistatic acoustic wind profiler.
Authors: Bradley Stuart , von H|$$̈unerbein Sabine
Published: October 2013

We describe signal coding for a new design of SODAR (atmospheric acoustic RADAR) used for profiling atmospheric turbulence and winds. This bistatic SODAR uses a central vertically pointing transmitter and three synchronized phased-array scanning receivers spatially distributed on the ground and, at any instant, simultaneously pointing at the same region of the central atmospheric column. There are distinct advantages if continuous transmission can be used, since total signal power and fast profile acquisition are enhanced. However, the weak echoes mean that the receivers will record a combination of transmitted and scattered sound, so the two need to be orthogonal. This suggests a signal coding scheme. However, turbulent scattering acts similarly to an acoustic reflective diffraction grating, and this places severe constraints on signal coding. We therefore explore a sawtooth linear FMCW system, designed to optimize separation of echo and direct signal, while not detuning too much the Bragg diffraction grating relationship. An implementation of this new bistatic system and first results are discussed.
Translating acoustical concepts from large to small multipurpose performance spaces.
Authors: Silva Richard , Chu William
Published: October 2013

The design of small or large multipurpose performance spaces involves similar subjective listening parameters when considering the same types of acoustical programs. Such design includes sound absorptive material selection for reverberation control, and wall and reflector shaping for sound reflection or diffusion. However, simply scaling the same physical features does not necessarily achieve the same acoustical design goals. Drawing from a few case studies, this paper explores several design principles for small performance spaces and compares their acoustical effectiveness to their larger performance space counterparts.
Mode coupling induced by random ocean sound speed structure: Mean intensity and revisiting the evolution equations for the cross-mode coherences.
Authors: Colosi John , Morozov Andrey
Published: October 2013

The seminal papers of Dozier and Tappert (1978), Dozier (1983), and Creamer (1996) have analyzed mode coupling induced by a random ocean sound speed structure to derive transport equations for the range evolution of mean mode energy. A major assumption in this work is that the cross-mode coherences rapidly decay with range and can thus be ignored. Theoretical predictions of mode energy have been compared to a direct Monte Carlo simulation, yielding favorable results [Dozier and Tappert (1978) and Creamer (1996)], so the general accuracy of the transport equations cannot be questioned. However, if the observable of interest is the mean acoustic intensity, one will quickly realize that the cross-mode coherences do not decay rapidly with range and thus need to be estimated for accurate acoustic predictions; an example from deep ocean propagation will be provided. This paper presents a theoretical framework for computing cross-mode coherences and demonstrates why the coherences are not important for the evolution of mode energy.
Application of the evoked-potential method to the study of the odontocete biosonar.
Authors: Supin Alexander
Published: October 2013

In a false killer whale Pseudorca crassidens, auditory evoked potentials (AEPs) were recorded in conditions of echolocation using both real targets and electronically synthesized and played-back (phantom) echoes. The electronic echoes were triggered by emitted sonar pulses, their spectra were similar to that of the emitted sonar clicks of the subject, and their intensities were proportional to the level of the emitted sonar pulse. AEPs to both the emitted pulse and real or electronic echoes were well detectable. AEPs related to emitted sonar clicks displayed the regular amplitude dependence on click level: The higher the level, the higher the amplitude. The echo-related AEP amplitudes depended on both echo attenuation and delay with a trade of around 9-dB attenuation per delay doubling. When the echo attenuation was varied in conjunction with delay keeping a rate of 9-dB deeper attenuation per delay doubling, the echo-related AEPs were nearly invariant. This result is well explainable by a hypothesis implying that partial forward masking of echoes by preceding emitted sonar pulses serves as a mechanism of automatic gain control in the auditory system of echolocating odontocetes.
Measurements of attenuation of sound in marine sediments at low frequencies.
Authors: Chapman Ross , Jiang Yong-min
Published: October 2013

This paper describes an experimental technique for measuring the attenuation of sound in marine sediments at low frequencies. The method makes use of the signals from sub-bottom reflectors that are received on a vertical hydrophone array at close ranges in shallow water environments. The signal path geometry is determined from an inversion of the travel time differences of the sea bottom and sub-bottom reflected paths to estimate the sediment sound speed and the depth of the sub-bottom reflector. The method is applied to data from experiments carried out at a site on the New Jersey continental shelf in the Shallow Water 06 experiment. The sediment type and the structure of the sediment column were ground truthed by independent measurements at the site. The chirp signal was transmitted in two frequency bands, from 100–900 and 1500–4500 Hz, and the data were match filtered to obtain the multipath signals at the array. A prominent signal from a sub-bottom interface known as the R-reflector was resolved in the data for each frequency band. Results are presented for the average attenuation over the depth to the reflector. [Work supported by ONR Ocean Acoustics.]
Hank Bass and the origins of the National Center for Physical Acoustics.
Authors: Crum Lawrence
Published: October 2013

The National Center for Physical Acoustics was established by an Act of Congress due principally to the efforts of Henry Bass. This presentation will review the history behind the NCPA and the various roles that Hank played in making this center a reality.
Exposure effects on production and perception development for the learners of English as a second language.
Authors: Kang Seokhan
Published: October 2013

Exposure effects for L2 production and perception development were examined. Two types of intervowel VCV stop voicing with different accents (iambus and trochee) were presented to ten English native speakers, ten English-learning Korean university students who had residence experience in America, and ten English-learning Korean university students who had no residence experience in America. Results showed that L2 patterns of Korean students’ production and perception with residence experience in America were in between the English native speakers and the Korean students without residence experience. However, the asymmetrical development patterns between the production and perception for the two Korean groups could be found. In the production tests, the prosodic factor deeply influences on the asymmetrical development. The difference is in the trochee pattern rather than in the iambic pattern. It means that residence experience improves prosody knowledge in their production. Also this effect has some influence on both the temporal and fundamental frequency features but not on the formant features. The acoustic difference could be seen in the perception tests, too. We could not find any difference in the identification test of the word-medial iambic environment. Rather the difference could be found in the cue influence test in the trochaic environment.
Identification and Rescue of α-Synuclein Toxicity in Parkinson Patient–Derived Neurons
Authors: Chung Chee Yeun , Khurana Vikram , Auluck Pavan K. , Tardiff Daniel F. , Mazzulli Joseph R. , Soldner Frank , Baru Valeriya , Lou Yali , Freyzon Yelena , Cho Sukhee , Mungenast Alison E. , Muffat Julien , Mitalipova Maisam , Pluth Michael D. , Jui Nathan T. , Schüle Birgitt , Lippard Stephen J. , Tsai Li-Huei , Krainc Dimitri , Buchwald Stephen L. , Jaenisch Rudolf , Lindquist Susan
Published: October 2013

From Yeast to Therapeutic?

Yeast has shown some promise as a model system to generate lead compounds that could have therapeutic potential for the cellular problems associated with neurodegenerative diseases. Along these lines,

Tardiff
et al.

(p.
979
, published online 24 October) and

Chung
et al.

(p.
983
, published online 24 October) describe the results of multiple screens in yeast that lead to the identification of a potential therapeutic compound to combat the cytotoxic affect of α-synuclein accumulation. The compound was able to reverse the pathological hallmarks of Parkinson's disease in cultured neurons derived from patients with α-synuclein–induced Parkinson's disease dementia.
Genome Sequence of
Rhodococcus
sp. Strain BCP1, a Biodegrader of Alkanes and Chlorinated Compounds
Authors: Cappelletti M. , Di Gennaro P. , D'Ursi P. , Orro A. , Mezzelani A. , Landini M. , Fedi S. , Frascari D. , Presentato A. , Zannoni D. , Milanesi L.
Published: October 2013

Rhodococcus
sp. strain BCP1 cometabolizes chlorinated compounds and mineralizes a broad range of alkanes, as it is highly tolerant to them. The high-quality draft genome sequence of
Rhodococcus
sp. strain BCP1, consisting of 6,231,823 bp, with a G+C content of 70.4%, 5,902 protein-coding genes, and 58 RNA genes, is presented here.
Complete Genome Sequence of an Avian Bornavirus Isolated from a Healthy Canadian Goose (
Branta canadensis
)
Authors: Guo Jianhua , Baroch John , Randall Adam , Tizard Ian
Published: October 2013

A recent survey among wild birds demonstrated the presence of a unique genotype of avian bornavirus (ABV) in wild geese and swans in North America. Here, we report the first complete genome sequence of an avian bornavirus of the goose genotype.
Complete Genome Sequences of Five
Chrysodeixis chalcites
Nucleopolyhedrovirus Genotypes from a Canary Islands Isolate
Authors: Bernal Alexandra , Williams Trevor , Muñoz Delia , Caballero Primitivo , Simón Oihane
Published: October 2013

The
Chrysodeixis chalcites
single nucleopolyhedrovirus (ChchSNPV) infects and kills
C. chalcites
larvae, an important pest of banana crops in the Canary Islands. Five genotypes present in the most prevalent and widespread isolate in the Canary Islands were sequenced, providing genetic data relevant to the genotypic and phenotypic diversity of this virus.
Draft Genome Sequence of
Bacillus
sp. Strain NSP2.1, a Nonhalophilic Bacterium Isolated from the Salt Marsh of the Great Rann of Kutch, India
Authors: Dey Rinku , Pal Kamal Krishna , Sherathia Dharmesh , Dalsania Trupti , Savsani Kinjal , Patel Ilaxi , Sukhadiya Bhoomika , Mandaliya Mona , Thomas Manesh , Ghorai Sucheta , Vanpariya Sejal , Rupapara Rupal , Rawal Priya , Saxena Anil Kumar
Published: October 2013

The 5.52-Mbp draft genome sequence of
Bacillus
sp. strain NSP2.1, a nonhalophilic bacterium isolated from the salt marsh of the Great Rann of Kutch, India, is reported here. An analysis of the genome of this organism will facilitate the understanding of its survival in the salt marsh.
Complete Genome Sequence of the Escherichia coli PMV-1 Strain, a Model Extraintestinal Pathogenic E. coli Strain Used for Host-Pathogen Interaction Studies
Authors: Peris-Bondia Francesc , Muraille Eric , Van Melderen Laurence
Published: October 2013

Escherichia coli
is a highly versatile species, causing diverse intestinal and extraintestinal infections. Here, we present the complete genome sequence of PMV-1, an O18:K1 extraintestinal pathogenic
E. coli
(ExPEC) strain that is used as a model for peritonitis in mice and was useful for deciphering the innate immune response triggered by ExPEC infections.
A twist in the tale
Authors: Malhotra Rishi , Daniel Rejoo , Besarovic Sanja
Published: October 2013

A 4-year-old girl presented with retching and abdominal colic and was initially diagnosed with gastroenteritis. However, progressive pain and epigastric distension led to a surgical review and she was discovered on CT scanning to have a gastric volvulus. She required urgent laparotomy to decompress the stomach and repair a perforation on the lesser curvature. Her recovery was complicated by sepsis and reperforation necessitating further laparotomy, at which time she also underwent gastropexy. The patient required long-term jejunal feeding in the hospital and at home before finally returning to normal diet and activity.
Emergency and trauma care in Pakistan: a cross-sectional study of healthcare levels
Authors: Razzak Junaid A , Baqir Syed M , Khan Uzma Rahim , Heller David , Bhatti Junaid , Hyder Adnan A
Published: October 2013

Background

The importance of emergency medical care for the successful functioning of health systems has been increasingly recognised. This study aimed to evaluate emergency and trauma care facilities in four districts of the province of Sindh, Pakistan.

Method

We conducted a cross-sectional health facility survey in four districts of the province of Sindh in Pakistan using a modified version of WHO’s Guidelines for essential trauma care.93 public health facilities (81 primary care facilities, nine secondary care hospitals, three tertiary hospitals) and 12 large private hospitals were surveyed. Interviews of healthcare providers and visual inspections of essential equipment and supplies as per guidelines were performed. A total of 141 physicians providing various levels of care were tested for their knowledge of basic emergency care using a validated instrument.

Results

Only 4 (44%) public secondary, 3 (25%) private secondary hospitals and all three tertiary care hospitals had designated emergency rooms. The majority of primary care health facilities had less than 60% of all essential equipments overall. Most of the secondary level public hospitals (78%) had less than 60% of essential equipments, and none had 80% or more. A fourth of private secondary care facilities and all tertiary care hospitals (n=3; 100%) had 80% or more essential equipments. The average percentage score on the physician knowledge test was 30%. None of the physicians scored above 60% correct responses.

Conclusions

The study findings demonstrated a gap in both essential equipment and provider knowledge necessary for effective emergency and trauma care.
Gastrointestinal parasitic burdens in UK tortoises: a survey of tortoise owners and potential risk factors
Authors: Hedley J. , Eatwell K. , Shaw D. J.
Published: October 2013

Despite gastrointestinal parasites being commonly diagnosed in captive tortoises throughout the UK, there is a lack of data regarding the prevalence. The aims of this study were to investigate the prevalence of gastrointestinal parasites in tortoises in the UK, and to investigate the factors affecting the prevalence of these parasites. Owners were invited to submit a faecal sample from their tortoise in conjunction with a completed questionnaire covering details of signalment and husbandry. Data from the questionnaires were analysed at the end of the study. Faecal analysis was performed on samples from Testudo hermanni, Testudo graeca and Testudo horsfieldii. This involved examination of direct wet preparations, a modified McMaster technique, passive NaCl flotation and Cryptosporidium staining. Of the 142 samples used, 130 were examined by the first three methods. 49 per cent were positive for one or more parasites. Of the positive samples, 67 per cent were positive for oxyurids, 28 per cent were positive for ascarids and 28 per cent were positive for protozoa (Balantidium, Nyctotherus or flagellates). Only 1/113 (0.8 per cent) samples was positive for Cryptosporidium. The most important risk factors for parasites were sex (F) and length of time (<5 years) in owner's possession. This survey showed that gastrointestinal parasites are frequently detected in the faecal samples of captive tortoises in the UK, but their prevalence may be influenced by various factors including sex, length of time owned, age and species.
Consumer perceptions of the Nutrition Facts table and front-of-pack nutrition rating systems
Authors: Emrich Teri E. , Qi Ying , Mendoza Julio E. , Lou Wendy , Cohen Joanna E. , L’Abbé Mary R.
Published: October 2013

Preferences for, and consumer friendliness of, front-of-pack (FOP) nutrition rating systems have not been studied in a Canadian population, and studies comparing systems that are accompanied by mandatory labelling, such as Canada’s Nutrition Facts table (NFt), are lacking. The purpose of this study was to evaluate 4 FOP systems relative to the NFt with respect to consumer friendliness and their influence on perceptions of the healthiness and nutrient content of food. Canadian consumers (n = 3029) participating in an online survey were randomized to score the consumer friendliness of 1 of 5 FOP conditions with or without an NFt and to score the healthiness and nutrient content of 2 foods using the provided label(s). The mean differences in scores were evaluated with analysis of covariance (ANCOVA) controlling for age, gender, and education, with Tukey–Kramer adjustments for multiple comparisons. The NFt received the highest scores of consumer friendliness with respect to liking, helpfulness, credibility, and influence on purchase decisions (p < 0.05); however, consumers still supported the implementation of a single, standardized FOP system, with the nutrient-specific systems (a “Traffic Light” and a Nutrition Facts FOP system) being preferred and scored as more consumer friendly than the summary indicator systems. Without the NFt, consumer ratings of the healthiness and calorie and nutrient content differed by FOP system. With the NFt present, consumers rated the healthiness and calorie and nutrient content similarly, except for those who saw the Traffic Light; their ratings were influenced by the Traffic Light’s colours. The introduction of a single, standard, nutrient-specific FOP system to supplement the mandatory NFt should be considered by Canadian policy makers.
Research agenda to support sodium reduction in Canada
Authors: Sherman Philip M. , Makarchuk Mary-Jo , Belanger Paul
Published: October 2013

The Sodium Reduction Strategy for Canada includes an identification of priority areas for future research, based on a workshop convened by the Canadian Institutes of Health Research (CIHR) and partners. A strong portfolio of research is essential to addressing current developments and controversies raised in relation to the health outcomes associated with dietary sodium. CIHR aims to provide leadership in working together with other funders and partners to catalyze a broad range of sodium research.