bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of Expectation Disconfirmation on Appraisal, Affect, and Behavioral Intentions
Authors: Sweeny Kate , Dillard Amanda
Published: October 2013

People's risk perceptions can have powerful effects on their outcomes, yet little is known about how people respond to risk information that disconfirms a prior expectation. We experimentally examined the affective, cognitive, and behavioral consequences of expectation disconfirmation in the context of risk perceptions. Participants were randomly assigned and then prompted toward either a high or low personal risk estimate regarding a fictitious health threat. All participants then received the same risk feedback, which presented either a negative disconfirmation experience (i.e., worse than expected) in the high‐risk estimate condition or a positive disconfirmation experience (i.e., better than expected) in the low‐risk estimate condition. Participants who experienced the negative disconfirmation reported stronger intentions to prevent the threat in the future compared to participants who experienced the positive disconfirmation. This effect was mediated by both disappointment about the risk feedback and perceptions of the severity of the threat. These findings have implications for risk communication, suggesting that the provision of objective risk information may improve or diminish the likelihood of behavior change depending on people's initial expectations and their emotional and cognitive reactions to the information.
Risk Management: History, Definition, and Critique
Authors: Dionne Georges
Published: October 2013

The study of risk management began after World War II. Risk management has long been associated with the use of market insurance to protect individuals and companies from various losses associated with accidents. Other forms of risk management, alternatives to market insurance, surfaced during the 1950s when market insurance was perceived as very costly and incomplete for protection against pure risk. The use of derivatives as risk management instruments arose during the 1970s, and expanded rapidly during the 1980s, as companies intensified their financial risk management. International risk regulation began in the 1980s, and financial firms developed internal risk management models and capital calculation formulas to hedge against unanticipated risks and reduce regulatory capital. Concomitantly, governance of risk management became essential, integrated risk management was introduced, and the chief risk officer positions were created. Nonetheless, these regulations, governance rules, and risk management methods failed to prevent the financial crisis that began in 2007.
Retirement Expectations and Satisfaction with Retirement Provisions
Authors: de Bresser Jochem , van Soest Arthur
Published: October 2013

This paper investigates the relationship between subjective expectations regarding the replacement rate of income at retirement and several measures of pension satisfaction. We use panel data on Dutch employees, analyzed with fixed effects models, allowing for correlation between unobserved heterogeneity in satisfaction and optimism or pessimism in expectations. The level of the expected replacement rate is found to be positively related to satisfaction: respondents who revise their expectations of the level of their replacement rate upwards tend to become more satisfied with their pension provisions, in particular with the level of the expected benefits. We do not find robust evidence for a relationship between uncertainty and pension satisfaction.
Provenance diversification within an arc‐trench system induced by batholith development: the Cretaceous Japan case
Authors: Aoki Kazumasa , Isozaki Yukio , Kofukuda Daisuke , Sato Tomohiko , Yamamoto Atsushi , Maki Kenshi , Sakata Shuhei , Hirata Takafumi
Published: October 2013

By comparing detrital zircon U–Pb age spectra of coeval fore‐arc and back‐/intra‐arc basin sandstones, we identified the overall distributary pattern of terrigenous clastic material within the Cretaceous arc system of SW Japan. Abundant Proterozoic (c. 1500–2500 Ma) detrital grains from the interior of East Asia are present in the Cretaceous intra‐arc basin. However, after a barrier mountain range formed during batholith emplacement, Proterozoic clastics were rarely transported into the fore‐arc domain. Episodic batholith formation in Pacific‐type orogens likely played a major role in controlling terrigenous supply routes between coeval back‐arc and fore‐arc domains. The Cretaceous orogen in Japan thus provides a good template for analysing the tectono‐sedimentary development of other arc‐related basins.
Successful treatment with fumagillin of the first pediatric case of digestive microsporidiosis in a liver‐kidney transplant
Authors: Desoubeaux G. , Maakaroun‐Vermesse Z. , Lier C. , Bailly É. , Morio F. , Labarthe F. , Bernard L. , Chandenier J.
Published: October 2013

We report the first successful use, to our knowledge, of fumagillin alone in a pediatric patient to cure intestinal microsporidiosis in a liver‐kidney transplanted child. Detection of Enterocytozoon bieneusi in stool became negative from the first post‐therapeutic control, while digestive symptoms disappeared in 4 days. During a 9‐month follow‐up, polymerase chain reaction and direct examinations remained negative for microsporidia in her feces. No major undesirable effects were noted during the anti‐microsporidial therapy.
The ruins of Erskine Beveridge
Authors: MacDonald Fraser
Published: October 2013

This is a narrative essay, the animating purpose of which is stylistic as much as analytic. It is a story; and, unusually for academic geography, the story is primary. The essay has no deferred object; it is not ‘about’ something more academic but nor does it abrogate the work of analysis. It narrates the story of the Scottish archaeologist Erskine Beveridge and his family, as told through a prolonged encounter with the ruins of his house situated on the Hebridean island of North Uist. A discussion of ruins, archives and fieldwork runs parallel with, but always subsidiary to, the main narrative.
On the Replacement of Shoe-Wheel Brakes by Pad-Disk for Railroad Freight Cars
Authors: José Romano Sergio , de Carvalho Santos Francisco , Santos Auteliano A.
Published: October 2013

Most of railroad freight cars use brake shoes directly applied onto the wheels. This system causes wheel heating, which in turn gives rise to thermal stresses and loss of mechanical strength. An alternate solution is a system of brake disks and pads, which would not heat the wheels, like disk brakes. Because temperature is one major factor affecting braking performance, a study of the viability of replacing shoe brakes by disk brakes must evaluate and compare the heating of wheels and disks. The present work evaluates the heating of disk-pad systems when used for braking freight cars in the same conditions regularly applied to shoe-wheel brakes. In addition, stop distance for both systems are evaluated for regular speeds of freight railroads. Preliminary numerical simulations were done to choose the critical brake condition and to check whether the expected temperatures would exceed the temperature limits, damaging the friction materials and systems. Following that, real scale tests were conducted in critical braking conditions for both types of brake systems. Dynamometer tests were performed in real scale at the Railroad Laboratory of the State University of Campinas, Brazil. Results showed that, as far as system heating is concerned, there is nothing to prevent the replacement of the current system by a disk-pad system. Besides, the stop distance for both systems is also in the recommended range.
Numerical Simulation of Saturated Flow Boiling Heat Transfer of Ammonia/Water Mixture in Bubble Pumps for Absorption–Diffusion Refrigerators
Authors: Jo Soo W. , Sherif S. A. , Lear W. E.
Published: October 2013

This paper addresses a multidimensional numerical simulation of the saturated flow boiling heat transfer in bubble pumps of absorption–diffusion refrigeration cycles. The bubble pump with a shape of vertical tube is subjected to a uniform heat flux from the tube outer wall surface along the entire pump length. As the bubble pump wall is heated, a nonazeotropic mixture of saturated strong ammonia/water entering into the bubble pump transforms to ammonia vapor and diluted ammonia/water mixture. The weaker ammonia/water mixture is lifted by the buoyant force created by the ammonia vapor. The present multidimensional numerical simulation was performed using the two-fluid model with the equilibrium phase change model and the standard k-ε turbulence model. The numerical model designed for the present simulation was validated through a comparative study referring to available experimental data. The present numerical model was compared with the one-dimensional model to assess its applicability for numerical simulation of the saturated flow boiling heat transfer in bubble pumps. As a result, it is seen that the present numerical model predicts the performance of ammonia/water bubble pumps more realistically than the one-dimensional model. In addition, the effects of the bubble pump's geometrical dimension and heat input on the pump performance were investigated using the present numerical approach.
Physical and electrical characterization of Ce-HfO2 thin films deposited by thermal atomic layer deposition
Authors: King Peter J. , Sedghi Naser , Hall Steve , Mitrovic Ivona Z. , Chalker Paul R. , Werner Matthew , Hindley Sarah
Published: October 2013

This paper describes the deposition and characterization of Ce-modified HfO2 thin films. Layers were deposited on Si(100) substrates by thermal atomic layer deposition using (MeCp)2Hf(OMe)(Me), Ce(mmp)4, and H2O as the precursors. Spectroscopic ellipsometry and medium energy ion scattering were used to measure the thicknesses and compositions of the deposited films. After postdeposition annealing, a metastable cubic phase is found to be stabilized in the films. Capacitance–voltage measurements have been used to characterize the dielectric properties of deposited films before and after two annealing regimes. The equivalent oxide thickness of an as-deposited sample with nominal high-κ dielectric thickness of 6 nm is circa 2.8 nm from which the dielectric constant 31 was calculated. The leakage current density is in order of 10−6 A/cm2 at ±1 V. The fabrication of Ce-HfO2 films without plasma or O3-based atomic layer deposition represents a potentially useful manufacturing route for future scaled devices.
Breast Imaging Reporting and Data System (BI‐RADS) breast composition descriptors: Automated measurement development for full field digital mammography
Authors: Fowler E. E. , Sellers T. A. , Lu B. , Heine J. J.
Published: October 2013

Purpose:

The Breast Imaging Reporting and Data System (BI‐RADS) breast composition descriptors are used for standardized mammographic reporting and are assessed visually. This reporting is clinically relevant because breast composition can impact mammographic sensitivity and is a breast cancer risk factor. New techniques are presented and evaluated for generating automated BI‐RADS breast composition descriptors using both raw and calibrated full field digital mammography (FFDM) image data.

Methods:

A matched case‐control dataset with FFDM images was used to develop three automated measures for the BI‐RADS breast composition descriptors. Histograms of each calibrated mammogram in the percent glandular (pg) representation were processed to create the new BRpg measure. Two previously validated measures of breast density derived from calibrated and raw mammograms were converted to the new BRvc and BRvr measures, respectively. These three measures were compared with the radiologist‐reported BI‐RADS compositions assessments from the patient records. The authors used two optimization strategies with differential evolution to create these measures: method‐1 used breast cancer status; and method‐2 matched the reported BI‐RADS descriptors. Weighted kappa (κ) analysis was used to assess the agreement between the new measures and the reported measures. Each measureˈs association with breast cancer was evaluated with odds ratios (ORs) adjusted for body mass index, breast area, and menopausal status. ORs were estimated as per unit increase with 95% confidence intervals.

Results:

The three BI‐RADS measures generated by method‐1 had κ between 0.25–0.34. These measures were significantly associated with breast cancer status in the adjusted models: (a) OR = 1.87 (1.34, 2.59) for BRpg; (b) OR = 1.93 (1.36, 2.74) for BRvc; and (c) OR = 1.37 (1.05, 1.80) for BRvr. The measures generated by method‐2 had κ between 0.42–0.45. Two of these measures were significantly associated with breast cancer status in the adjusted models: (a) OR = 1.95 (1.24, 3.09) for BRpg; (b) OR = 1.42 (0.87, 2.32) for BRvc; and (c) OR = 2.13 (1.22, 3.72) for BRvr. The radiologist‐reported measures from the patient records showed a similar association, OR = 1.49 (0.99, 2.24), although only borderline statistically significant.

Conclusions:

A general framework was developed and validated for converting calibrated mammograms and continuous measures of breast density to fully automated approximations for the BI‐RADS breast composition descriptors. The techniques are general and suitable for a broad range of clinical and research applications.
An acoustic modeling study of airgun noise from seismic surveys performed offshore British Columbia
Authors: MacGillivray Alexander O. , Chapman N. Ross
Published: October 2013

A recent numerical modeling study has examined the propagation of underwater noise from potential seismic survey activity in Hecate Strait and Queen Charlotte Sound, Canada. Noise level predictions from this study are based on an integrated modeling approach incorporating an airgun array source model, a broadband transmission loss model, and an environmental model based on high resolution bathymetry, historical CTD casts and geophysical data. Details of the source model, transmission loss model and environmental model are discussed. Selected noise level predictions from the modeling study are presented. Results from this study will aid in evaluating potential environmental impacts of seismic exploration activity on marine ecosystems in British Columbia’s offshore region. [Work supported by BC MEM and NSERC.]
A new method for measuring the speech security of meeting rooms
Authors: Bradley John S. , Gover Bradford N.
Published: October 2013

This paper describes a proposed new method for measuring the speech security of offices and meeting rooms. It is intended to assess the risk of someone who is talking in the meeting room being overheard at points outside the room, close to the outside boundaries of the room. Previous work has derived frequency-weighted speech-to-noise type measures that are well related to the perceived intelligibility and audibility of the transmitted speech. The proposed new method measures the attenuation between average levels in the meeting room and received levels at points 0.25 m from the outside boundaries of the meeting room in adjacent spaces. The average source room levels are representative of all possible talker location. The receiving points, 0.25 m from the room boundaries, can assess expected privacy at critical listening locations with minimal effect of the acoustical properties of the adjacent spaces. New measurements in 11 meeting rooms have been used to evaluate the influence of several parameters on the accuracy of the measured degree of speech security. These include: the type and number of sound sources used, and the number and location of microphones in the meeting room and the adjacent spaces. Details of the analyses will be presented.
Subjective impression of differences in realism, source width, and orientation between auralizations created from multi-channel anechoic recordings
Authors: Vigeant Michelle C. , Wang Lily M. , Rindel Jens Holger
Published: October 2013

Auralizations can be very useful in the design of performing arts spaces. One of the fundamental modeling inputs to create auralizations is the source directivity. Standard methods involve inputting the measured source directivity, calculating the impulse response (IR) and convolving it with a single channel anechoic recording. This paper focuses on an alternative method of modeling source directivity which involves multi-channel anechoic recordings to create auralizations. Subjective tests were conducted comparing auralizations made with one, four and thirteen channels for differences in realism and source width. Auralizations were made using three different types of musical instruments: woodwinds (flute), brass (trombone) and strings (violin). Subjects were asked to rate each musical track on a seven-point scale for the degree of realism and source width. An analysis of variance (ANOVA) was carried out to determine the differences between the number of channels and the effect of instrument. A second test was conducted to assess the degree of difficulty in detecting source orientation (facing the audience or facing the stage wall) depending on the number of channels (one, four or thirteen) and the amount of absorption in the room. [Work supported by the National Science Foundation.]
Experimental validation of a diffusion equation-based modeling of the sound field in coupled rooms
Authors: Billon Alexis , Valeau Vincent , Picaut Judicael , Sakout Anas
Published: October 2013

Sound modeling in coupled rooms (i.e., two acoustically coupled rooms separated by an open area) has attracted considerable attention in the past. However accurate and operational models are still needed, principally when three or more rooms are coupled. In recent papers, a diffusion equation-based model has been applied to unusual room shapes. For the coupled rooms geometry, this diffusion model has been validated successfully by comparison with the classical statistical theory in a parametrical study of the coupling parameters [Billon et al., J. Acoust. Soc. Am. 116, 2553 (2004)]. In the present work, the diffusion model results are validated by means of a comparison with experimental results, both in terms of sound attenuation and reverberation time. A comparison is also provided with results given by the statistical theory and a ray tracing program. For this purpose, experiments have been conducted in two coupled classrooms with two different sound source locations. The results show a very good agreement between the diffusion model and the experiments. Conversely, the statistical model is not valid for modeling accurately the sound field distribution and decay in both coupled rooms. At last, the diffusion model runs much faster than the ray tracing program.
Common hearing functions among mammals and birds
Authors: Fay Richard R.
Published: October 2013

Among many mammals and birds, frequency-place cochlear maps have a similar form and differ primarily with respect to the length of the cochlea or basilar papilla, and with respect to the frequency range of hearing. This is remarkable, especially given the differences in anatomical organization and evolutionary history between mammals and birds. This is a striking example of convergent or parallel evolution. With few exceptions, the cochleae of mammals and birds are indeed scale models of one another. One of the primary functions of the frequency-place map is in frequency analysis. Whether this function is defined by frequency discrimination thresholds, critical masking ratios, critical bands or auditory filters in general, frequency analytic performance, behaviorally-defined, can be laid out on the basilar membrane and a critical basilar membrane distance can be associated with a given performance criterion. In general, these critical distances differ according to the function (e.g., frequency delta Fs versus critical bandwidths), but are remarkably similar functions of frequency within and between species (they tend to be constant). It seems likely that evolution has selected the consequences of frequency analytic mechanisms for perception rather than the mechanisms themselves. [Work supported by NIH.]
Psychometric data and standards for the estimation of noise exposure for animals
Authors: Bowles Ann E.
Published: October 2013

ASA standards are used in the estimation of noise exposure for humans. The approaches pioneered for humans can be used as a model for animal standards, but a number of differences must be considered. First, animal standards will normally be applied across multiple taxa rather than to a single, monotypic species. Thus, it will be essential to find defensible methods for generalizing across taxa. Second, samples of subjects and measurement conditions are often inadequate in animal studies (e.g., measurements on a single animal, noisy testing conditions), but may be the only data available. Therefore, standards are needed for specifying the limitations of various data sources. Third, taxa may have very different psychoacoustic capabilities (e.g., best sensitivity, temporal integration time, and loudness perception). Therefore, comparative measures will be essential. For example, while weighting functions for humans are standardized to zero at 1 kHz, there are advantages to developing weighting functions for animals with an appropriate correction for taxon-specific sensitivity. Although the differences between standards for animals and humans represent a significant challenge, the development process and research in support of animal standards will yield valuable new perspectives that could be applied to humans in the future.
Percutaneous high intensity focused ultrasound on pigs
Authors: du Plessis Herman , Vaezy Shahram
Published: October 2013

Two types of HIFU Handpieces were tested on pigs under general anesthesia. The direct applicator (focal distance 4 cm) was adequate to control bleeding from a liver injury, although direct pressure was effective in a shorter time. The percutaneous application did not work at all, as the fixed focal distance (6 cm) was too deep for the size pigs available, and the diagnostic modality was difficult to integrate with the therapeutic window. We were able to create necrotic lesions in the liver substance, but not in the areas where the injury was situated. More development is needed to build a better, user-friendly application device before HIFU can be used in the clinical situation for control of hemorrhage.
Characterization of a vibro-acoustography system designed to detect kidney stones during lithotripsy
Authors: Owen Neil R. , Bailey Michael R. , Crum Lawrence A.
Published: October 2013

Acoustic properties of a vibro-acoustography system designed to detect kidney stones were measured. Our system was formed with two spherical transducers (10 cm diameter, 20 cm curvature) in degassed water that were confocal and separated by an angle of 30 degrees. They were driven at 1.1 MHz and 1.125 MHz to generate a difference frequency of 25 kHz. The acoustic field was characterized by scattering from a known target, the curved surface of a steel cylinder with 6.4 mm diameter. Waveforms of both the low and high frequency scattered signals were measured for different target locations, different hydrophone locations encircling the target, and different acoustic pressures. Focal dimensions of the −6 db pressure profile measured at 25 kHz and the fundamental were both 3×10 mm, in an elliptical shape, which is highly localized. Scatter amplitude was rather insensitive to hydrophone position when the target was in the focus, quite sensitive to hydrophone position when the target was out of the focus, and increased linearly with the sum of the sources. It is hoped that this characterization will help improve the understanding of the mechanisms of the targeting technique. [Work supported by NIH grants DK43881 and DK55674, and NSBRI grant SMS00203.]
Digital identification of intrusive noise: Pilot study to digitally characterize soundscapes and intrusion
Authors: Lavallee Tim , Kull Robert , Schulte-Fortkamp Brigitte
Published: October 2013

One of the difficulties with soundscape investigation and the definition of intrusion is the need for an individual to manually identify and log specific acoustical events. Event logging can be labor intensive, costly, and difficult to standardize. If information about physical setting and in situ acoustical signatures can be used to define a given soundscape, event logging could possibly be performed digitally and intrusion could be defined based on the spectral fingerprint of a given soundscape. Two soundscapes with different settings and acoustical signatures were identified. Sound time histories and periodic third octave spectra were measured over a given period. An individual manually logged acoustical events. Independently, algorithms to identify both normal and acoustically intrusive events for the given soundscape were applied to the data. The digitally identified events were compared to the manually taken event log. An evaluation of the results will be presented.
Nonlinear acoustic experiments involving landmine detection: Connections with mesoscopic elasticity and slow dynamics in geomaterials, Part II
Authors: Korman Murray S. , Sabatier James M.
Published: October 2013

In nonlinear acoustic detection, airborne sound at two primary tones, f1, f2 (chosen several Hz apart from resonance) insonifies the soil surface over a buried landmine, and due to soil wave interactions with the landmine, a scattered surface profile can be measured by an LDV. Profiles at f1, f2, f1−(f2−f1) and f2+(f2−f1) exhibit a single peak while profiles at 2f1−(f2−f1), f1+f2 and 2f2+(f2−f1) are attributed to higher order mode shapes. The lowest resonant frequency for a VS 1.6 plastic, inert, anti-tank landmine, buried at 3.6 cm deep is ∼125 Hz. The ‘‘on target’’ to ‘‘off target’’ contrast ratio, for some of the nonlinearly generated combination tones, is roughly 15–20 dB higher compared to either primary component. Near resonance, the bending (softening) of a family of increasing amplitude tuning curves, involving the surface vibration over the landmine, exhibits a linear relationship between the peak particle velocity and corresponding frequency. The tuning curves exhibit hysteresis effects. Landmine-soil vibrations exhibit similar characteristics to nonlinear mesoscopic/nanoscale effects that are observed in geomaterials like rocks or granular materials. Nonlinear mechanisms of soil and the soil interacting with the top-plate of the mine case are compared. [Work supported by U.S. Army RDECOM CERDEC, NVESD.]
Nonlinear enhancement and saturation phenomena in focused ultrasound beams of various geometry
Authors: Khokhlova Vera A. , Basova Marina S. , Bailey Michael R. , Crum Lawrence A.
Published: October 2013

The effects of nonlinear enhancement of focusing gain and saturation are studied and compared for high-intensity focused ultrasound sources with an initial Gaussian shading and uniform amplitude distribution. Simulations are performed using the Khokhlov Zabolotskaya (KZ) nonlinear parabolic equation for weakly dissipative medium in a wide range of source linear focusing gains and source pressure amplitudes, including the strongly nonlinear regime with shocks. An artificial absorption proportional to the fourth power of frequency or an asymptotic frequency-domain approach is employed in the algorithm in order to reduce the number of harmonics for accurate modeling of strongly distorted waveforms with shocks. The effect of focusing gain and amplitude shading of the source on nonlinear enhancement of acoustic energy concentration and saturation levels at the focus is discussed. It is shown that nonlinear enhancement of focusing gain is different for different values of linear gain, different spatial distributions of the source amplitude, and different parameters of acoustic field. The levels of nonlinear saturation at the focus are obtained for very high source amplitudes. The results of simulations give lower enhancement and higher saturation levels compared to the known approximate analytic predictions. [Work supported in part by NIH Fogarty and NSBRI.]
Perception of combined intensity and frequency contours by normal-hearing and hearing-impaired listeners
Authors: Leek Marjorie R. , Molis Michelle R. , Lentz Jennifer J.
Published: October 2013

When a speaker utters a consonant-vowel or vowel-consonant syllable, the frequency transitions are critical to identification of the sound. However, an intensity contour is also superimposed on the frequency glides, as the mouth opens or closes. In this study, the interaction of frequency and intensity contours was explored using a frequency glide discrimination task. Offset frequency difference limens (offset DLs) were measured for upward and downward frequency glides in two frequency regions, and with three intensity contours, increasing from silence, decreasing to silence, and steady-state. For both normal-hearing (NH) and hearing-impaired (HI) subjects, larger offset DLs were observed for the high frequency stimuli than for the lower frequencies, and for upward-gliding stimuli than for downward frequency glides. Amplitude contour had little effect on the NH data, but did influence offset DLs for HI subjects. These findings indicate that for these stimuli, the interaction of frequency and amplitude contours plays only a small role in the perception of transition-like glides for NH listeners, but may affect the perception of frequency transitions by HI listeners. [Work supported by NIDCD.]
Masker variability effects in backward-masked frequency discrimination
Authors: Espinoza-Varas Blas , Jang Hyunsook
Published: October 2013

Masker variability effects have been studied mostly in detection tasks with simultaneous maskers; this paper reports variability effects in a frequency discrimination threshold (FDT) paradigm with backward maskers. FDTs for sinusoidal targets were measured unmasked (or in isolation) and in two backward-masked conditions: one included within-trial masker frequency variability, the other did not. The 1500-Hz, 40- or 80-ms targets, and 500-, 1500-, or 2500-Hz, 80-ms maskers were presented at 70-dB SPL with a 20-ms ISI. A standard and two comparisons were displayed, respectively, in the 1st, 2nd, and 3rd observation interval of a 3I/2AFC task. One comparison, chosen randomly with 0.5 probability, contained an increment in target frequency as specified by an adaptive rule that estimated 71 percent-correct FDTs. Identical increments in masker frequency were added to both comparisons in within-trial variability conditions, but not in conditions without variability. In all conditions, the task was to determine which comparison contained the target frequency increment. Masked no-variability FDTs were higher than unmasked FDTs, but training nullified this effect. Masker variability induced greater FDT elevations with 40- than with 80-ms targets, and in conditions having the same rather than different target-masker frequencies. Prolonged training nullified all masker variability effects.
Sensitivity to combined frequency and amplitude speech cues by cochlear implant users
Authors: Healy Eric W. , Rogers Cheryl F. , Montgomery Allen A.
Published: October 2013

Although a considerable amount of work has been directed toward examining the sensitivity of the cochlear implant (CI) user to various acoustic cues, less has examined the ability to combine cues. The sensitivity to concurrent cues was examined using an adaptive 3I-2AFC paradigm. Stimuli were synthesized three-syllable words having middle syllables that possessed an increase in fundamental frequency, amplitude or both. Sensitivity to increments in the individual cues was first measured for five subjects with a CI and five age-matched controls. These DLs were then used to equate sensitivity to the two cues and create stimuli having concurrent increments. It was found that the presence of the two cues reduced the mean DL to half that of either cue alone, for both groups of subjects. Thus, this combination of cues is similar across groups and simply additive. Individual differences in the ability of CI users to combine cues were more strongly predictive of performance on speech recognition tests than was sensitivity to either cue alone. These results have implications for the perception of the multiplicity of speech cues. [Work supported by NIDCD.]
Structural acoustic control of plates with variable boundary conditions
Authors: Clark Robert L. , Sprofera Joseph D. , Gibbs Gary P. , Cabell Ran H.
Published: October 2013

A method for optimizing a structural acoustic control system with respect to potential variations in plate boundary conditions is provided. The assumed modes method is used to build a plate model with varying levels of rotational boundary stiffness to span a range of possible boundary conditions which can be used to capture uncertainty in the model. A transducer placement scoring process, involving Hankel singular values (HSVs), is combined with a genetic optimization routine to find spatial locations robust to boundary condition variation. Predicted frequency response characteristics are examined, and optimized results are discussed in relation to boundary condition variations. Results indicate it is possible to minimize the impact of uncertain boundary conditions in active structural acoustic control by optimizing the placement of transducers with respect to uncertainties. Both analytical and experimental results will be discussed.
Spectral contributions to intelligibility of sentences with flattened fundamental frequency
Authors: Watson Peter J. , Schlauch Robert S.
Published: October 2013

Recently, the contribution of fundamental frequency (F0) variation to speech intelligibility in background noise has been studied [J. Laures and G. Weismer, JSLHR 42, 1148–1156 (1999)]. The process used for this analysis is to flatten the frequency contour at the average F0. Results show that sentences with flattened F0 are less intelligible than those with natural F0 variation. However, this technique may reduce the prominence of formant peaks because it excludes F0s that are below the average flattened frequency. As noted by Laures and Weismer (1999), eliminating lower F0s from the analysis results in wider spacing between the harmonics and the available energy to excite the vocal tract resonances is diminished. This study examined the effect of flattening at the average and lowest F0 of each sentence to intelligibility. Twenty subjects listened to sentences in a continuous noise background. Sentences were equated for root-mean square energy. Results showed that the low-flattened condition was significantly more intelligible than the average-flattened condition. However, a condition with natural F0 variation was more intelligible than the two flattened conditions. These findings show that that the frequency of flattening does contribute to intelligibility but that natural F0 variation appears to contribute to a greater degree.
The effect of auditory feedback alterations on the speech quality of hearing aid and cochlear implant users
Authors: Barac-Cikoja Dragana , Klein Leslie
Published: October 2013

The speech of seven hearing aid (HA) users with severe-profound hearing loss and six cochlear implant (CI) users was recorded as they read the Rainbow Passage while their speech feedback was either spectrally altered in real-time, completely masked by multi-talker babble noise, or unaltered. Spectral alterations were implemented by filtering the speech signal into either one or four frequency bands, extracting their respective amplitude envelope(s), and amplitude-modulating the corresponding noise band(s). While the single-band condition provided only coarse information about the speech rhythmic structure, the four-band noise signal remained intelligible. Auditory feedback was presented via insert earphones to the HA users, and via the auxiliary jack (with the headpiece microphone silenced) to the CI users, at the participants’ most comfortable listening level. The quality of the recorded speech (separated into individual sentences) was assessed using a 2IFC procedure. For each combination of the experimental conditions, six judges selected the more natural-sounding utterance in a pair. Preference scores were calculated for each of the four feedback conditions and statistically tested. HA and CI group differed in how feedback intelligibility affected the speech quality. Possible acoustic correlates of the perceived differences will be discussed.
Speech intelligibility index calculations in light aircraft cabin during flight
Authors: Bucak Tino , Bazijanac Ernest
Published: October 2013

High levels of cabin noise in small general aviation aircraft significantly deteriorate the quality of speech communications and potentially endanger the safety of flight. Several ground and inflight cabin noise measurements on new generation Cessna 172R were made during various phases of flight. The results are analyzed and used for Speech Intelligibility Index (SII) calculations, in order to quantify the influence of cabin noise on speech communications between crew members.
Speech rate characteristics in dysarthria
Authors: Tjaden Kris , Greenman Geoff , Juma Taslim , Pruitt Roselinda
Published: October 2013

Speech rate disturbances are pervasive in dysarthria, with some reports suggesting that up to 80% of speakers with dysarthria exhibit speech rates that differ from neurologically normal talkers. The contribution of articulation time and pause time to the overall impairment in speech rate is not well understood. Studies investigating speech rate characteristics in dysarthria also tend to focus on reading materials, yet there is reason to suspect that the higher cognitive load of conversational speech may impact speech rate characteristics differently for individuals with impaired speech motor control, and neurologically normal talkers. The current study will report speech rate characteristics for both a reading passage and conversational speech produced by individuals with dysarthria secondary to Multiple Sclerosis (MS), individuals with dysarthria secondary to Parkinson Disease (PD) and healthy controls. The manner in which speech rate, articulation rate, and pause characteristics differ for speakers with dysarthria and healthy controls will be examined. The contribution of articulation time and pause time to overall speech rate also will be studied and compared for the reading passage and conversational speech. [Work supported by NIDCD R01DC04689.]
Identification of strong scatterer locations on the Malta plateau
Authors: Prior Mark K.
Published: October 2013

Reverberation data gathered in the Malta Plateau region of the Mediterranean Sea using a Low-Frequency Active Sonar (LFAS) and a cardioid receiver array are presented. A processing strategy involving normalization, geo-referencing and averaging over pings is described and is shown to highlight the locations of strong scatterers and to provide a first-order estimate of their strength. A second process of calculating the ratio of local standard deviation and mean values is shown to reveal scatterer locations and to provide an indication of whether the probability density function of the reverberation is well-described by the Rayleigh distribution. The characteristics of the observed scatterers are revealed by comparison with independent sidescan, echo sounder and boomer data. Areas of high reverberation are identified as being associated with wrecks, oil production platforms, rock outcrops and variations in local sediment properties.
Noise localization ability in the Mongolian gerbil (Meriones unguiculatus)
Authors: Sarkar Srijata , Abrams Kristina S. , Carney Laurel H.
Published: October 2013

Understanding localization ability is essential for comparison to physiological studies of binaural neurons. Heffner and Heffner [Beh. Neuro. 102, 422 (1998)] reported relatively poor ability of the gerbil to localize a 100 ms noise burst (approximately 75% correct at 27° separation.) Their experimental setup required the gerbil to enter an observing response compartment, initiating a noise burst from one of two speakers separated by the test angle. The animal was required to respond by entering a reporting compartment, positioned 90° to the right or left, regardless of speaker location. This required mapping from speaker location to response location. In this study, response mapping was avoided in an effort to improve performance. After an observing response (jumping on a platform in the center of a circular cage), the animal responded by moving directly towards the active speaker. The results of this study were consistent with those of Heffner and Heffner at small angles of separation. [For 180° separation, this task resulted in poorer performance than the previous study, presumably due to lack of control of head orientation during stimulation, leading to front-back confusions.] In conclusion, the poor localiza tion ability of gerbils is apparently not explained by response mapping. [Work supported by NIDCD R01-DC001641.]
Relationships among perceived sexual orientation, perceived height, and perceived speech clarity
Authors: Munson Benjamin , McDonald Elizabeth C.
Published: October 2013

Previous research [B. Munson, Linguist. Soc. Am. (2005)] showed that listeners rate self-identified gay/lesbian/bisexual (GLB) talkers as more-GLB sounding than self-identified heterosexual talkers when listening to readings of single words in isolation. In this investigation, we examine relationships among measures of perceived sexual orientation (PSO) and two other perceptual measures made from the same talkers’ speech, perceived height and perceived speech clarity. Ratings were collected from three independent groups of listeners. Regression analyses showed that approximately 80% of the variance in PSO of women’s voices was predicted by measures of perceived clarity (women rated as speaking more clearly were more likely to be rated as heterosexual-sounding than women rated as speaking less clearly) and perceived height (women rated as sounding tall were more likely to be rated as GLB-sounding than women rated to sound short). In contrast, 50% of the variance in men’s sexual orientation was predicted by measures of perceived clarity (men rated as speaking more clearly were more likely to be rated as GLB-sounding than men rated as speaking less clearly). These results suggest that ratings of PSO from speech may be mediated by judgments of other parameters that are robustly coded in short samples of speech.
Pharynx depth and tongue height in relationship to intrinsic F0 of vowels
Authors: Whalen D. H. , Oliveira Leonardo , Gick Bryan
Published: October 2013

Intrinsic F0 (IF0) is the tendency for high vowels to have higher F0s than low vowels. It is universal and apparently automatic, but the exact mechanism is still unclear. Here, ultrasound measurements of the tongue were used to determine whether vowel height is the best predictor of IF0. Ten native speakers of English spoke keywords for the eleven non-diphthongal vowels while the lips, jaw, and tongue were imaged with the HOCUS ultrasound/Optotrak system [D. H. Whalen et al., J. Sp. Lang. Hear. Res. (in press)], which tracks the head and lips with optical markers while the tongue is imaged with ultrasound. The tongue edge can be extracted and rotated relative to the head, indicating changes in tongue height and pharyngeal depth. Preliminary analysis indicates that IF0 is better correlated with the most anterior point on the tongue root (indicating pharyngeal depth) than with the highest point on the tongue. It thus seems likely that the shape of the pharynx is more of a determinant than tongue height for IF0. Because pharynx depth and vowel height covary in most languages (including English), the earlier description is somewhat accurate; IF0 may be more accurately described as correlated to the tongue root.
Intrinsic factors of releasing motions in an articulator: On assuming segmental input in speech-production models
Authors: Boucher Victor J.
Published: October 2013

Prominent models of speech production use serial input that is assumed to be commensurate with linguistic segments. The view is that such units underlie a serial activation of aperture motions such as closing and opening motions of the lips in articulating a bilabial stop. This is incompatible with conventional EMG observations showing a single burst of activity of labial adductors at the onset of a close-open cycle. The present study examines the spring-like effects of bilabial compression and pressure on labial opening (release) following a relaxation of the orbicularis oris muscle. Using reiterative series [papapapa] produced at increasing intensities, the range and velocity of opening motions of the lower-lip were correlated with lip compression and oral-pressure. The results for three speakers show that pressure and compression are correlated and that these factors account for 45% to 66% of the variance in velocity of lower-lip opening, and for 47% to 73% of the variance in the range of lower-lip opening. These results complement earlier findings of Abbs and Eilenberg (1976) showing the intrinsic effects of muscle elasticity on opening motions of the lips. Close-open cycles in articulators may not reflect segment-by-segment serial activation.
Sound detection by coral reef fishes
Authors: Popper Arthur N.
Published: October 2013

Many coral reef fishes use sounds for communication. However, they, as all fishes, learn a good deal about their environment by listening to ambient noises produced by swimming fishes, water moving across the reef, rain, and many other sources. Such information provides these fishes with a sensory world that is far more extensive than from visual, chemical, or tactile cues. There is also a growing body of evidence that suggests that larval coral reef fishes that have not yet settled are able to detect, and swim towards, a reef through the use of the ambient sound of the reef. Studies of hearing by coral reef fishes show considerable variability in sound detection capabilities, sometimes even within the same taxonomic family. Studies have shown that different damsel fishes (Pomacentridae) can actually discriminate between sounds produced by their own species and other species within the group. Within the holocentrids, there are similarities in the sounds produced by different species, but considerable differences in the structure of the ear and in hearing capabilities of the same species. This paper will discuss sound detection by coral reef fishes, and the ability of fishes to detect and use the ‘‘auditory scene.’’
Sound detection of reef sounds by larvae of coral-reef fishes
Authors: Leis Jeffrey M. , Carson-Ewart Brooke M. , Cato Douglas H.
Published: October 2013

Nearly all teleost reef fishes are pelagic during the larval stage, returning at the end of this stage to settle in a reefal habitat. Little is known about their sensory capabilities or how larvae detect and locate a reef. Sound is the most likely cue, particularly since reef shrimp and fish choruses are audible at considerable distances. Playback experiments off Lizard Island, Great Barrier Reef, broadcast nocturnal reef sounds and artificial sounds (pure tones) in the presence of settlement stage larvae of the coral-reef damselfish Chromis atripectoralis, released during the day within 100 m of the underwater speaker 500–1000 m from the nearest reef. Larvae consistently swam to the south in the absence of playback and during playback of artificial sounds. During playback of reef sounds, they showed no overall swimming direction, indicating that they can hear and can distinguish between a sound with potential biological significance and one without. Light traps with and without playback of reef sounds on 33 paired (playback: nonplayback) trap nights resulted in higher catches for 14 of 17 families for which >10 individuals were trapped. This suggests that not only can larvae hear, but they also have some aural localization capability.