bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychometric functions of sentence recognition in amplitude-modulated noises
Authors: Shen Yi , Manzano Nicole , Richards Virginia M.
Published: May 2014

Although it is known that listeners can take advantage of the fluctuations in the temporal envelopes of background noises to improve the recognition of target messages, the amount of benefit is difficult to compare across listeners and experimental conditions. One solution to this difficulty is to estimate the psychometric functions for speech recognition instead of the speech reception threshold alone (i.e., the 50% correct point on the psychometric function). The current study utilized a rapid psychophysical procedure that enabled the robust estimation of the psychometric function for sentence recognition in noise using as few as 20 sentences. Using this procedure, sentence recognition was measured by presenting target sentences in amplitude-modulated noise maskers. In separate conditions, the target intensity (40 or 70 dB SPL) and the masker modulation rate (1–64 Hz) were systematically varied. Manipulating these two stimulus parameters influenced both the speech reception threshold and the slope of the psychometric function. Data collected from ten young, normal hearing listeners indicated that the fluctuating-masker benefit was much more evident at the higher target level and it exhibited non-monotonic dependencies on masker modulation rate.
Bayesian estimation of high-parameter models of the auditory filter
Authors: Shen Yi , Sivakumar Rajeswari , Richards Virginia M.
Published: May 2014

The Bayesian adaptive procedure proposed by Shen and Richards [J. Acoust. Soc. Am. 134(2), 1134–1145 (2013)] was extended to allow the rapid estimation of auditory filters that were asymmetric about their peak frequencies. The estimation of the auditory-filter shape (five free parameters) was achieved using single Bayesian adaptive tracks of 150–200 trials (approximately 15 min to complete). During the experimental track, listeners detected a tonal signal presented with either simultaneous or forward maskers. Both types of maskers consisted of two bands of noises, one on each side of the signal frequency. The Bayesian adaptive procedure iteratively updated the parameter estimates following each experimental trial and determined the stimulus that would maximize the gain of information on the following trial. The stimuli were adaptively manipulated along three dimensions: the masker level and the spectral location of the upper and lower masker bands. The proposed procedure allowed the reliable estimation of the auditory-filter shape for naïve normal-hearing listeners. The model predictions replicated the known effect of the masker-signal simultaneity on the auditory filter.
Do normal-reading listeners use “perceptual anchors” in frequency-discrimination tasks?
Authors: Mathias Samuel R. , Micheyl Christophe , Shinn-Cunningham Barbara
Published: May 2014

A controversial hypothesis about the origins of dyslexia states that dyslexic listeners are poor at frequency discrimination when the standard frequency is fixed from trial to trial because they find it difficult to use “perceptual anchors.” This hypothesis tacitly assumes that normal listeners use perceptual anchors during fixed-frequency discrimination, which they cannot do when the standard frequency is random (“roved”). To test this assumption, we measured frequency-discrimination performance in normal listeners for tones separated by silent intervals (ISIs) of up to 10 s. Critically, in either the first or second half of the experiment (counterbalanced across listeners), the frequency of the first tone was the same on each trial (“fixed” conditions); in the other half, the frequency of this tone was random (“roved” conditions). The data were analyzed using a model that estimated the precision of frequency representations. In the roved conditions, frequency representations were less precise at longer ISIs, indicating that they experienced decay. By contrast, frequency representations experienced little decay in the fixed conditions. The results are consistent with the assumption that normal listeners used perceptual anchors in the fixed conditions because, by definition, perceptual anchors should be stored in long-term memory and therefore less susceptible to decay.
Effect of spatial discontinuity on short-term memory for melodic sequences
Authors: Wang Audrey S. , Varghese Lenny A. , Mathias Samuel R. , Shinn-Cunningham Barbara G.
Published: May 2014

We investigated whether spatially separating segments of a tone sequence split the sequence into separate perceptual streams, and whether it affected how pitch information was stored in memory. Listeners heard a sequence of six 300-ms complex tones presented either to a single ear, or with the first three and last three tones presented to different ears. They reported whether a subsequent monaural probe tone matched a tone in the original sequence, based solely on pitch (disregarding the ear to which the probe was played). Overall, performance was higher when the probe tone matched either the first or one of the last two tones in a target compared to when the probe matched more interior target elements. For single-ear target sequences, presentation of the probe in the opposite ear diminished performance compared to when it was presented in the same ear as the target. Spatially splitting the target sequence had very little effect. The results suggest that the tone sequences were perceived as a single stream, irrespective of whether there was spatial discontinuity. However, a probe in an unexpected location confused listeners, perhaps causing a spatial attention shift that diminished the already-weak memory representation of the interior tones' pitches.
An analysis of the weighted sum of spatial gradients (WSSG) control metric in active structural acoustic control
Authors: Cao Yin , Sommerfeldt Scott D. , Blotter Jonathan D. , Aslani Pegah
Published: May 2014

The choice of the control metric used and how it is measured is an important factor in active structural acoustic control (ASAC) and has been a topic of research for many years. In ASAC, the objective is to minimize the radiated power, but this metric is difficult to implement in practice. Previous research has identified a control metric named the weighted sum of spatial gradients (WSSG) that has demonstrated effectiveness in attenuating the radiated power from a plate. This metric only requires local vibration information on the plate and hence is easier to implement than previous control metrics. It is also largely insensitive to boundary conditions. In addition, ASAC using WSSG has been demonstrated to be generally more effective than using volume velocity as the control metric. This paper demonstrates that WSSG closely approximates the ideal of using the radiated sound power as the control objective. It will be shown that the weights used to implement WSSG are also very important, as they directly impact the control effectiveness. Both theoretical and experimental results show that optimum weights exist to implement WSSG. These results suggest that WSSG has the potential ability to be used in more practical and complex structures.
A fully coupled finite element-boundary element vibro-acoustic analysis for laminated composite structures with enclosed acoustic cavities
Authors: Sahu Atanu , Guha Niyogi Arup , Rose Michael , Bhattacharya Partha
Published: May 2014

A major contribution of aircraft cabin noise is due to the vibrating airframe structure in which the use of lightweight composite materials is quite common. Due to the strong influence of such vibrating structures on the enclosing fluid, such as air, and vice-versa, a fully coupled analysis involving both the systems is necessary in many cases. Hence the present work details a fully coupled vibro-acoustic analysis of such type of flexible cavity subjected to the external mechanical excitation based on a coupled finite element (FE) and boundary element (BE) approach. The structural mode shapes and eigen frequencies are computed using the FE free vibration analysis of in-vacuo structures, which are subsequently coupled through the mobility equation with the acoustic part modeled with the BE method. The developed approach is also well compared with the fully coupled FE approach but the advantage derived here is that it is sufficient to model each domain independently thus reducing the problem dimension. The discussed method ensures full coupling between the two systems considering the cavity acoustic back pressure and also enables a fully coupled analysis of a double-walled structure attached to an acoustic cavity which resembles a true aircraft cabin.
Interaction of memory and specificity in auditory repetition priming
Authors: Zellou Georgia , Embick David
Published: May 2014

This study examines the influences of abstract and episodic representations of words in auditory repetition priming. Two manipulations of prime and target items were employed, token-change and voice-change. First, either the target item consisted of a different token spoken by the same speaker as the prime (token-change), or the target item was a token spoken by a different speaker/different gender (voice-change) than the prime. Second, lapse between prime and target varied across three conditions: no-lapse (no intervening trials between prime and target), medium-lapse (exactly ten intervening trials), and long-lapse (exactly 20 intervening trials). Stimuli were presented using an auditory lexical decision task (with an equal number of English-like nonwords). The reaction time data reveal the greatest facilitation between token-change no-lapse prime-target pairs (256 ms), followed by voice-change no-lapse pairs (182 ms). Facilitation effects were comparable across both the medium-lapse and long-lapse conditions, and there was no advantage for token-change over voice-change items. We interpret these results in terms of current models of lexical access in which episodic representation are available only immediately after presentation, while abstract representations are active for a longer time.
Emergent tonogenesis in Afrikaans
Authors: Coetzee Andries W. , Beddor Patrice S. , Wissing Daan P.
Published: May 2014

Afrikaans is usually described as having a contrast between prevoiced and voiceless unaspirated plosives ([b]-[p], [t]-[d]). This study documents an ongoing change in the pre-vocalic realization of the contrast. Preliminary data from five speakers show that all speakers produce some phonologically voiced plosives without prevoicing, with frequency of devoicing ranging from 30% to 85% across speakers. This devoicing is nearly categorical: VOTs of devoiced plosives average 12 ms and those of phonologically voiceless plosives average 17 ms. (By comparison, VOTs of voiced plosives average around Ő130 ms.) The contrast appears to be preserved in the F0 contour of the following vowel, which is 50 to 100 Hz lower (depending on the speaker) after phonologically voiced than after phonologically voiceless plosives. The F0 difference continues through at least 70% of the vowel. However, post-plosive F0 variation is not contingent on devoicing, e.g., F0 contours after phonological /b/ are the same regardless of whether the production is [p] or [b]. In these preliminary data, the magnitude of the F0 difference is linked to speaker age, with younger speakers showing a larger difference. Data from a larger group of speakers are being analyzed and will be presented.
Listen to your mother: Highly familiar voices facilitate perceptual segregation
Authors: Johnsrude Ingrid , Casey Elizabeth , Carlyon Robert P.
Published: May 2014

We studied the effect of voice familiarity on the ability to segregate one voice from a competing speaker. Specifically, we examine the utility of arguably the most familiar voice of all—the mother’s voice—in facilitating segregation, and compared it to the effect of a voice that listeners had been familiarized with in the laboratory. We tested 19 older adolescents (still living at home) on a version of the coordinate-response-measure procedure (CRM; Bolia et al., 2001), with mixtures of two voices, at three signal-to-noise ratios (Ő3 dB, 0 dB, + 3 dB). Performance was better when the mother’s voice was the target, compared both to novel and lab-familiar targets. At the most disadvantageous target-to-masker ratio (Ő3 dB), listeners were also better able to ignore their mother’s voice so as to comprehend a stranger’s voice more effectively, demonstrating that extremely familiar voice information facilitates segregation. This pattern of results is similar to that observed with older people (aged 44–59) when their spouse’s voice was present in a two-voice CRM mixture (Johnsrude et al., 2013). The new results demonstrate the importance of long-term (rather than short-term) familiarity and show that it aids sound segregation for adolescents as well as older adults.
Audio/visual correlates of a vowel near-merger in the Bay Area
Authors: Johnson Keith , Bakst Sarah
Published: May 2014

This study is a part of a research program aiming to learn the extent to which visual phonetic information may be involved in the maintenance of an acoustically weak or marginal contrast. The “caught/cot” contrast is one such contrast which has been merged in much of the western United States. We seek to document both the presence of the contrast in the SF Bay area and the phonetic realization of it. We will be reporting on audio/visual recordings from 33 native English speakers from the Bay Area (14 from San Francisco). Participants read a brief passage and a set of sentences that targeted these vowels, and then completed a commutation task where speakers tried to identify their own productions of the words “cot” and “caught.” We found that three of the speakers reliably made the caught/cot contrast, and phonetic analysis confirms that regardless of whether speakers perceive a distinction, the vowels may differ acoustically or on degree of visual lip rounding, depending on the context. The two vowels tend to be most distinct in the single-word context and the least in the passage context. [Funded by the NSF.]
Production and perception of the pre-lateral, non-low, back vowel merger in northeast Ohio
Authors: Arnold Lacey R.
Published: May 2014

This study examines the status of the pool/pull, pole/pull, and pool/pull/pole mergers in the Youngstown, Ohio area, as well as various factors that may influence perception of these mergers. The participants include 16 natives of the Youngstown, Ohio area, ranging from ages 9–66, and making up two separate families; one individual belonged to neither. The findings suggest that all three mergers can be found in the Youngstown area, though each is undergoing a different process. Results of the perception task suggest that individuals can use additional cues, such as vowel duration, to aid in identification of words containing merged phonemes. Findings also suggest that homophonous words uttered by merged speakers in the context of a carrier sentence may contain additional information that listeners are able to access and utilize for word identification. Lastly, the effects of familiarity with the speaker and merged/distinct production on word identification reveal no definitive results, though the study’s findings suggest further investigation of these factors would be a worthwhile endeavor.
Perceptual tonal spaces in whispered speech
Authors: Kuo Grace
Published: May 2014

Whispered speech is made when no vocal fold vibration occurs. However, pitch from whispers can still be perceived for some listeners because it corresponds to the change in F1 and F2. Listeners rely on the laryngeal movements, which not only associate with pitch change but also result in the change of the tongue position as well as the shape of the oral cavity. This study examines the acoustical-perceptual relationships in the identification of pitch during whispered tone production. Listeners (English and Taiwanese) rate the similarity of fifty AX tonal pairs (Taiwanese [ka℧] and [ɕ] in modal voice vs. whispered voice). Multidimensional scaling (MDS) analysis is used to map English listeners’ and Taiwanese listeners’ perceptual tonal spaces regarding modal speech and whispered speech stimuli. The correlations between the similarity ratings, the reciprocal of their reaction time, and the selected acoustic measures are examined.
Dynamic pitch and pitch range interact in distortions of perceived duration of American English speech tokens
Authors: Brugos Alejna , Barnes Jonathan
Published: May 2014

Previous research showed that pitch factors can distort perceived duration: tokens with dynamic or higher f0 tend to be perceived as longer than comparable level-f0 or lower-f0 tokens, and silent intervals bounded by tokens of widely differing pitch are heard as longer than those bounded by tokens closer in pitch (the kappa effect). Fourteen subjects were asked to judge which of two exemplars of a spoken word sounded longer. All tokens were created from the same base file with manipulations of objective duration, f0 contour (plateaux vs. rises of different slopes) and pitch range. Results show that pitch range relation between the two exemplars was a stronger predictor of perceived duration distortion than f0 contour. In addition to previously demonstrated effects of f0 height (Yu, 2010), greater f0 discontinuity between tokens increases the likelihood that the first token of a pair will be judged as longer, suggesting that some previous findings showing the effects of dynamic pitch on perceived duration may actually be magnified by the kappa effect. Listeners may be responding to perceived prosodic distance that integrates information from timing (filled and silent intervals) and pitch (pitch slope and pitch jumps across silent intervals).
Indexical variation affects semantic spread
Authors: King Ed , Sumner Meghan
Published: May 2014

The role of indexical variation in spoken word recognition is constrained to acoustically rich lexical representations. Theoretically, lexical activation depends on indexical variation, but subsequent processes like associative semantic spread depend on activation strength, not indexical variation. Social psychological theories view indexical variation as integral to online processes such as persona construal. Therefore, information gleaned from indexical variation might pervade spoken word recognition more broadly. We investigate the effects of indexical variation on semantic activation in word-association and semantic-priming paradigms. Across three studies, we show that top associate responses depend on the voice of the probe word (“space” in man’s voice: time; woman’s voice: star; child’s voice: planet). Voice also affects response frequency distributions: the man’s voice receives a wider variety of weaker responses, while the woman’s and child’s voices receive fewer, stronger, responses. We also find that semantic priming varies as a function of voice-specific word association strength: priming is stronger to strong voice-specific associates (woman: space-star) than to weak associates (woman: space-time). We argue that indexical variation affects spoken word recognition beyond an episodic lexicon and provide an account capturing effects of learned associations between acoustic patterns and linguistic and social features in spoken language processing.
Distribution and propagation of sound sources in the vocal tract
Authors: Oren Liran , Khosla Sid , Gutmark Ephraim
Published: May 2014

In the current study, an array of 128 microphones is strategically positioned outside a vocal tract model that is placed above an excised canine larynx. Acoustic holography technique is then used to identify the distribution of sound in the vocal tract by using simultaneous measurements from the microphone array. The results show that with no downstream constriction (i.e., open mouth) the energy coming from the higher harmonics is concentrated near the vibrating folds. When downstream constriction is added (i.e., partially closed mouth), the energy in the higher harmonics is shifted further downstream toward the mouth. These results suggest that acoustic holography can be used as a new tool to assess how sound sources propagate in the vocal tract during normal speech and consequently determine the severity of certain speech disorders such as hypernasality and nasal emission.
Assessment of heart rate variability from speech analysis
Authors: Deshpande Nivedita , Thakur Kavita , Zadgaonkar Arun S.
Published: May 2014

In this paper, various methods of heart beat variability assessment from speech analysis have been presented. Heart rate variability (HRV) is a physiological phenomenon where the time interval between heart beats varies. It is measured by the variation in the beat-to-beat interval. The present work deals with the HRV detection from speech parameters. RR-cycle detects one heart beat. Continuous monitoring of electrocardiograph for a span of time can provide HRV. More than 250 samples of normal informants as well as heart patients with enlarged heart have been collected during the four years of research work. The regular ECG and speech samples of the patient have been collected and analyzed. Further they had compared with the parameters of a normal healthy informant. Speech samples were collected through a microphone and subjected to be digitized. The required speech segmental have been extracted and analyzed through a DSP tool, PRAAT. ECG sample has been recorded through an ECG machine. A technique of HRV detection from speech analysis has been presented in this paper. The HRV detection from speech can be a very helpful tool in monitoring the functioning of human heart.
Improvement of speech coding algorithm based on DSP system
Authors: Wu Xiaochen , Lv HaiNing
Published: May 2014

With the rapid development of the communication technology, the high quality of speech communication has become one of the main development trends. In order to solve the quality problem in the processing of communication, pre emphasis is used to improve the quality of the high frequency components in codec algorithm. The speech enhancement of spectral subtraction is also applied in this speech coding algorithm to improve the ability of anti noise. Repackaging the sending frames and redefining the length of the frame that need to be send in the algorithm in order to realize the low speed in speech communication process. At last, the speech quality will be proved by PESQ—MOS test and the spectrogram. From the test and the figure, the quality of the synthesized speech especially with background noise has been significantly improved.
Acoustic transfer functions and speech intelligibility in permanent wearing headsets
Authors: Popov Vladimir G. , Ushakov Alexey L. , Laris Zintars , Batov Serge , Saprovskii Yurii
Published: May 2014

A detailed analysis of the acoustic transfer functions has been investigated for different locations of the headset microphones in the area of human head. Amplitude-frequency and phase-frequency characteristics of acoustic signals are discussed in the report. The signals have been recorded with the micro-mechanical-electrical-system (MEMS) microphones located on a mannequin, simulating the acoustic properties of the human torso. The the source of the signals is an emitter built in the mouth of the manikin's head. Analysis of the characteristics has shown that the acoustic signals undergo significant phase and amplitude changes associated with the interference and diffraction processes. These changes result in significant nonlinearity phase characteristics, and this nonlinearity depends on the installation location of the MEMS microphone. Also quality of speech intelligibility has been estimated by the method of expert evaluation and the speech has been recorded for different positions of the microphones and speaker head. A comparative analysis of the results has shown the optimal location of the microphones in the ear and on the breast of man.
Relationships between acoustic surface wave shape inversion and receiver array statistics in a variety of sea states
Authors: Walstead Sean , Deane Grant
Published: May 2014

Mid-frequency (12 kHz) acoustic scattering from the sea surface is analyzed with regard to surface wave shape inversion and receiver array characteristics. The forward scattered data is from the Surface Processes and Communications Experiment (SPACE08). Multipath arrivals representing surface, bottom-surface, and surface-bottom paths are distinguishable, implying that knowledge of the surface is known approximately 1/3, 1/2, and 2/3 the distance between source and receiver. Surface wave shape inversion at those ranges are presented in a variety of environmental conditions and compared to other calculable statistics such as vertical and horizontal array correlation length. The relationship between temporal fluctuations in the intensity of the surface reflected multi-path and array spatial coherence is investigated. To what extent receiver array statistics related to acoustic focusing follows environmental conditions such as wind speed and sea state are considered.
Sound propagation in a model ocean with internal waves: experiments and simulations
Authors: Zhang Likun , Benavides Santiago J. , Swinney Harry L.
Published: May 2014

We conduct laboratory experiments and numerical simulations in a laboratory tank where sound waves and internal gravity waves are simultaneously generated and detected. The tank contains a density-stratified fluid with internal gravity waves produced by a wave generator. Acoustic sources and receivers are arranged such that the acoustic track crosses the internal wave beam. The internal wave energy density, energy flux, and total power are determined from particle imaging velocimetry measurements. The internal wave field is also computed in direct numerical simulations of the Navier-Stokes equations, using a parallelized finite-volume based solver code. The fluctuations in sound speed and intensity are determined as a function of the acoustic track location and the internal wave amplitude, frequency, phase, and modulation frequency. This research is designed to achieve a better understanding of sound propagation and scattering by internal waves in the oceans. [This research was supported by ONR MURI Grant N000141110701 (WHOI). L.Z. acknowledges the support of the 2013-14 ASA F. V. Hunt Postdoctoral Research Fellowship.]
Amplitude and phase fluctuations of the sound fled in vicinity of horizontally stratified perturbation in shallow water (parabolic equation modeling)
Authors: Qin Jixing , Katsnelson Boris
Published: May 2014

Based on the approach of vertical modes and the parabolic equation (PE) in horizontal plane, three-dimensional (3D) effects in propagation of sound signals are considered: structure variation of broadband signal in the presence of horizontal stratification, such as coastal wedge area, temperature front, and nonlinear internal waves. Main factor, influencing on sound propagation is dependence of horizontal refraction on frequency and mode number. The following effect are studied: interference between direct and reflected signals in multipath area of horizontal plane for different frequencies and mode numbers, different directions of amplitude and phase front, evolution of spectrum and shape of pulse. [Work was supported by RFBR and BSF.]
Development and Validation of a Measure of Sport Fans’ Specific Curiosity
Authors: Park Seong-Hee , Ha Jae-Pil , Mahony Daniel
Published: May 2014

While there is a relatively rich literature measuring curiosity outside of sport, there is little research on measuring sport fans’ curiosity. Based on Berlyne’s (1960) two dimensions of curiosity, the current research project aimed to develop a reliable and valid measurement scale for sport fans’ specific curiosity. Convenience samples of university students were used. Three studies were used to develop the 11-item Sport Fan Specific Curiosity Scale (SFSCS) was developed. Specifically, the SFSCS consisted of three factors: specific information (5 items), general information (3 items), and sport facility information (3 items). The SFSCS was found to be a reliable and valid scale to measure sport fans’ specific curiosity. The scale should be useful in predicting aspects of sport fan behavior for sport fans at various stages.
Leadership Succession and Performance: An Application to College Football
Authors: Dohrn Stephanie , Lopez Yvette P. , Reinhardt Gilles
Published: May 2014

This article examines the impact of leader succession on organizational performance. We argue that both time and size of program are critical factors that need to be considered to appropriately determine the impacts of the leader succession on performance. We focus our analysis on the National Collegiate Athletic Association (NCAA) Football Bowl Subdivision (FBS) and examine the effect of performance-related coaching firings on on-field performance (win-loss percentage, Sagarin rating, Sagarin rank) and financial performance (team revenue). We cluster teams into three categories based on revenue and analyze team performance following leader succession after the first, second, and fourth year following the change. While most studies in this area report findings consistent with vicious cycle theory or ritual scapegoating, our findings offer primary support for common sense theory and ritual scapegoating, contingent on time and the size of the program as determined by team revenue.
Escalation of Commitment in United States Collegiate Athletic Departments: An Investigation of Social and Structural Determinants of Commitment
Authors: Hutchinson Michael , Nite Calvin , Bouchet Adrien
Published: May 2014

Amid evidence of limited financial benefit, universities in the United States continue increasing their commitment to the NCAA’s highest level of competition. Consequently, it is believed that such behavior is the result of more intangible motivations by university decision makers. Using escalation of commitment theory as a framework, the authors explored social and structural determinants of increasing commitment, specifically examining the role of organizational status, former performance, and side-bets in commitment escalation. Applying a collective case study approach, the authors examined institutions (N = 10) having increased their commitment to Division I athletics within the last 10 years. Serving as the primary data source, participants (n = 35) included decision makers involved in the implementation of escalation initiatives. QSR International’s NVivo 10 software was employed for data analysis in the application of a three-step coding process. Findings revealed unique theoretical advancement in the emergence and role of organizational status in commitment escalation. Further, decision makers identified the impact of former organizational performance in the decision to increase athletic commitment. Finally, findings revealed the increased significance of organizational side-bets serving as the sole means for sustaining course of action commitment.
A Direct Comparison of Short-Term Audiomotor and Visuomotor Memory
Authors: Ward Amanda M. , Loucks Torrey M. , Ofori Edward , Sosnoff Jacob J.
Published: May 2014

Audiomotor and visuomotor short-term memory are required for an important variety of skilled movements but have not been compared in a direct manner previously. Audiomotor memory capacity might be greater to accommodate auditory goals that are less directly related to movement outcome than for visually guided tasks. Subjects produced continuous isometric force with the right index finger under auditory and visual feedback. During the first 10 s of each trial, subjects received continuous auditory or visual feedback. For the following 15 s, feedback was removed but the force had to be maintained accurately. An internal effort condition was included to test memory capacity in the same manner but without external feedback. Similar decay times of ~5–6 s were found for vision and audition but the decay time for internal effort was ~4 s. External feedback thus provides an advantage in maintaining a force level after feedback removal, but may not exclude some contribution from a sense of effort. Short-term memory capacity appears longer than certain previous reports but there may not be strong distinctions in capacity across different sensory modalities, at least for isometric force.
Differential Postural Control and Sensory Organization in Young Tennis Players and Taekwondo Practitioners
Authors: Fong Shirley S.M. , Chung Joanne W.Y. , Ng Shamay S.M. , Ma Ada W.W. , Chow Lina P.Y. , Tsang William W.N.
Published: May 2014

This study compared the sensory organization and standing balance of adolescent tennis players, taekwondo (TKD) practitioners, and healthy control participants. Sixty participants including 12 tennis players, 21 TKD practitioners, and 27 healthy control participants were tested. All of the participants underwent the Sensory Organization Test (SOT) and the Unilateral Stance Test (UST) on a Smart Equitest system. Results revealed that tennis players had higher SOT visual ratios than the control participants (p = .005), and TKD practitioners swayed more slowly in the UST than the control participants (p = .039). No differences (p > .05) were found in the composite score, somatosensory ratio, or vestibular ratio between the groups. Tennis players swayed less when they relied more on visual input to maintain balance, whereas TKD practitioners were more stable when standing on one leg. Parents may consider these sports as recreational activities for their children to develop specific balance abilities.
Disruption of CXCR2-Mediated MDSC Tumor Trafficking Enhances Anti-PD1 Efficacy
Authors: Highfill Steven L. , Cui Yongzhi , Giles Amber J. , Smith Jillian P. , Zhang Hua , Morse Elizabeth , Kaplan Rosandra N. , Mackall Crystal L.
Published: May 2014

Preventing trafficking of myeloid-derived suppressor cells to the tumor site enhances the efficiency of checkpoint blockade.
SNFing Out Vulnerability in Cancer
Authors: Faltas Bishoy M.
Published: May 2014

SWI/SWF proteins, including ARID1A and ARID1B, are required for cellular resistance to DNA damage.
The Haemophilus ducreyi LspA1 Protein Inhibits Phagocytosis By Using a New Mechanism Involving Activation of C-Terminal Src Kinase
Authors: Dodd Dana A. , Worth Randall G. , Rosen Michael K. , Grinstein Sergio , van Oers Nicolai S. C. , Hansen Eric J.
Published: May 2014

Haemophilus ducreyi
causes chancroid, a sexually transmitted infection. A primary means by which this pathogen causes disease involves eluding phagocytosis; however, the molecular basis for this escape mechanism has been poorly understood. Here, we report that the LspA virulence factors of
H. ducreyi
inhibit phagocytosis by stimulating the catalytic activity of C-terminal Src kinase (Csk), which itself inhibits Src family protein tyrosine kinases (SFKs) that promote phagocytosis. Inhibitory activity could be localized to a 37-kDa domain (designated YL2) of the 456-kDa LspA1 protein. The YL2 domain impaired ingestion of IgG-opsonized targets and decreased levels of active SFKs when expressed in mammalian cells. YL2 contains tyrosine residues in two EPIYG motifs that are phosphorylated in mammalian cells. These tyrosine residues were essential for YL2-based inhibition of phagocytosis. Csk was identified as the predominant mammalian protein interacting with YL2, and a dominant-negative Csk rescued phagocytosis in the presence of YL2. Purified Csk phosphorylated the tyrosines in the YL2 EPIYG motifs. Phosphorylated YL2 increased Csk catalytic activity, resulting in positive feedback, such that YL2 can be phosphorylated by the same kinase that it activates. Finally, we found that the
Helicobacter pylori
CagA protein also inhibited phagocytosis in a Csk-dependent manner, raising the possibility that this may be a general mechanism among diverse bacteria. Harnessing Csk to subvert the Fcγ receptor (FcγR)-mediated phagocytic pathway represents a new bacterial mechanism for circumventing a crucial component of the innate immune response and may potentially affect other SFK-involved cellular pathways.

IMPORTANCE
Phagocytosis is a critical component of the immune system that enables pathogens to be contained and cleared. A number of bacterial pathogens have developed specific strategies to either physically evade phagocytosis or block the intracellular signaling required for phagocytic activity.
Haemophilus ducreyi
, a sexually transmitted pathogen, secretes a 4,153-amino-acid (aa) protein (LspA1) that effectively inhibits FcγR-mediated phagocytic activity. In this study, we show that a 294-aa domain within this bacterial protein binds to C-terminal Src kinase (Csk) and stimulates its catalytic activity, resulting in a significant attenuation of Src kinase activity and consequent inhibition of phagocytosis. The ability to inhibit phagocytosis via Csk is not unique to
H. ducreyi
, because we found that the
Helicobacter pylori
CagA protein also inhibits phagocytosis in a Csk-dependent manner. Harnessing Csk to subvert the FcγR-mediated phagocytic pathway represents a new bacterial effector mechanism for circumventing the innate immune response.
A painful soft tissue mass secondary to impingement of a metal on polyethylene bearing total hip arthroplasty
Authors: William Griffiths-Jones , Daniel Williams
Published: May 2014

A 60-year-old woman underwent a metal on polyethylene total hip replacement. The patient experienced pain and sustained multiple dislocations over the following 2 years and was referred for consideration of revision surgery. At the time of revision surgery it was found that there was a significant amount of polyethylene wear likely to have arisen as a result of the neutral cup placement and subsequent anterior impingement. A large cystic mass was excised and on histology was found to contain tissue with a lymphocytic infiltrate with a large amount of intracellular birefringent debris, consistent with polyethylene. The appearance of such masses is well reported as pseudotumours in metal-on-metal hip replacements but as yet their aetiology is unknown. We believe that the formation of the mass in this case could represent a model by which these pseudotumours occur.
The development of pulmonary aspergillosis and pneumothorax in a patient with neutropenic systemic lupus erythematosus and successful treatment of the first case
Authors: Pamuk Omer Nuri , Pamuk Gulsum Emel , Barutcu Ebru , Dogan Celik Aygul
Published: May 2014

There are reports on patients with systemic lupus erythematosus (SLE) with aspergillosis; however, aspergillosis-related pneumothorax has not been reported in SLE. We present a female patient with active SLE who was administered high-dose steroids, developed an opportunistic bacterial infection and had a cavitary pulmonary lesion. Sputum cultures yieldedAspergillus fumigatus. She was administered voriconazole. She developed dyspnoea and chest X-ray showed pneumothorax. She was placed with an underwater drainage chest tube; the pneumothorax and the pulmonary lesion regressed.
Improving patient outcomes in hereditary angioedema: reducing attack frequency using routine prevention with C1 inhibitor concentrate
Authors: Dominas Nina , Hoffmann Thomas K , Bas Murat , Greve Jens
Published: May 2014

Hereditary angioedema (HAE) is a rare inherited disorder, characterised by recurrent oedema attacks in various regions of the body. In HAE, mutations in the C1 esterase inhibitor (C1-INH) gene result in decreased C1-INH concentrations (type I HAE) or functionally deficient C1-INH (type II HAE), leading to inappropriate activation of the kallikrein–kinin system and release of vasoactive mediators. Treatment of HAE aims to manage acute attacks (using replacement C1-INH or bradykinin B2 receptor antagonist) or prevent attacks through prophylaxis (using C1-INH or attenuated androgens). We present a case of a 67-year-old man with HAE who suffered a high number of breakthrough HAE attacks while undergoing long-term prophylaxis with attenuated androgens. Androgen therapy was safely discontinued and routine prevention therapy with C1-INH (1000 U) introduced as part of an individualised management approach, in line with published clinical trial data, which improved patient outcomes in terms of HAE attack frequency and severity.
The dangers of living in a tent in London
Authors: De Butts Richard Frederick , Li Anna , Goodhand James , Wood Eleanor
Published: May 2014

A middle-aged patient was admitted severely unwell with acute liver and renal failure of unknown cause. After extensive investigation the patient was found to have leptospirosis. We examine the investigations and management and discuss the disease itself.
Hodgkin's lymphoma rectosigmoid in a patient with ulcerative colitis on long-term azathioprine therapy
Authors: Khuroo Mehnaaz S
Published: May 2014

Hodgkin's lymphoma complicating chronic ulcerative colitis is extremely rare. We report a case of extranodal Hodgkin's lymphoma involving rectosigmoid in a patient of chronic ulcerative colitis on long-term azathioprine. A 67-year-old man presented with extensive ulcerative colitis, on follow-up since September 2005. He received long-term steroids, mesalamine and azathioprine. Serial surveillance colonoscopic examinations and colonic biopsies were performed. Surveillance colonoscopy performed 8 years after the onset of disease showed multiple deep ulcers and nodular masses involving the rectum and sigmoid colon. Histological examination of rectosigmoid biopsies showed classic Hodgkin's disease. Azathioprine was withdrawn. He received mechlorethamine, vincristine, procarbazine and prednisone (MOPP) chemotherapy protocol and was planned for total colectomy in follow-up. We believe patients with ulcerative colitis on long-term azathioprine should be on vigil for development of lymphomas by protocol surveillance colonoscopic examinations and biopsies. The risk of lymphoma in such patients is small and outweighs the benefits of long-term azathioprine therapy.
Endometrioma contained within the broad ligament
Authors: Trehan Abhishek , Trehan Ashwini K
Published: May 2014

We present a rare case of an endometrioma present within and firmly adherent to the broad ligament in a patient who experienced an episode of acute abdominal pain. The endometrioma was excised laparoscopically and the broad ligament repaired.
Paediatric giant cervicomediastinal thymolipoma
Authors: Patel Ramnik V , Evans Kathryn , Sau Indranil , Huddart Simon
Published: May 2014

We report a case of a 11-year-old boy who presented with a massive soft tissue right cervical painless and progressive lesion displacing trachea to the left and extending into the anteriosuperior mediastinum which was diagnosed to be a lipomatous mass on chest CT scan. Subsequent biopsy and total excision proved it to be a giant cervicomediastinal thymolipoma. It was successfully excised with excellent prognosis and long-term results. A giant paediatric cervicomediastinal thymolipoma is a rare, benign, mediastinal mass of thymic origin. It may remain asymptomatic despite massive size and up to 50% in some series are associated with autoimmune disease. CT scan gives fat density and encapsulated benign nature and biopsy usually establishes the diagnosis. Preoperative tissue diagnosis is important as now the availability of thoracoscopic option is best suited to reduce morbidity. Treatment of choice is total excision using open surgical, minimal invasive techniques or robotic surgery and the prognosis is excellent.
Salt-losing nephropathy in hypothyroidism
Authors: Bautista Aileen Azul , Duya Jose Eduardo De Leon , Sandoval Mark Anthony Santiago
Published: May 2014

A 35-year-old man presented with recurrent lower extremity weakness associated with polyuria later progressing to generalised weakness with difficulty in breathing. The patient was hypotensive and dry, with normal thyroid and chest examination, weak lower extremity and carpopedal spasm. Workup revealed hypokalaemia, hyponatraemia, hypocalcaemia, hypomagnesaemia, hypochloraemia and hypophosphataemia. Arterial blood gas showed respiratory alkalosis with good oxygenation. Twenty-four-hour urine collection showed normal volume with electrolyte wasting. Thyroid function test revealed overt hypothyroidism with negative antithyroid peroxidase. The patient was well after treatment with levothyroxine, volume and electrolyte replacement and was discharged. Thyroid hormones are related to the expression of the Na-K-ATPase, Na-Pi cotransporter, Mg-ATPase and Na-Ca exchanger pumps in the renal tubules. Sodium, potassium, phosphate, calcium, magnesium and water losses result from decreased expression of these pumps.
Managing advanced unilateral pseudoexfoliative glaucoma
Authors: Marques André
Published: May 2014

The only proven therapy for glaucoma is intraocular pressure (IOP) reduction, which can be accomplished by different means. Each should be properly discussed with patients in order to best preserve visual function and quality of life. We report a case of unilateral pseudoexfoliative glaucoma, treated for years with triple topical IOP-lowering drugs. The patient presented with advanced optic neuropathy and important ocular side effects secondary to the treatment. Having discussed his options and prognosis, laser trabeculoplasty was performed while maintaining the remaining therapy considering the advanced stage of glaucoma. His IOP was effectively reduced and no progression was noted after 1-year follow-up. Although medical therapy is the mainstream in glaucoma management, its side effects should not be ignored, especially in unilateral cases. Surgery might have been a better solution, but we chose to perform laser trabeculoplasty, an effective and safer alternative, considering the unlikely but serious risk of the “wipe-out phenomenon” in this case.
A protocol for a randomised, double-blind, placebo-controlled study of the effect of LIraglutide on left VEntricular function in chronic heart failure patients with and without type 2 diabetes (The LIVE Study)
Authors: Jorsal Anders , Wiggers Henrik , Holmager Pernille , Nilsson Brian , Nielsen Roni , Boesgaard Trine Welløv , Kumme Anja , Møller Jacob Eifer , Videbæk Lars , Kistorp Caroline , Gustafsson Ida , Tarnow Lise , Flyvbjerg Allan
Published: May 2014

Introduction

Heart failure is one of the most common cardiovascular complications of diabetes and the most disabling and deadly complication too. Many antidiabetic agents have been associated with increased morbidity and mortality in a subset of patients with chronic heart failure (CHF); thus, new treatment modalities are warranted. Interestingly, a beneficial effect of the incretin hormone, GLP-1, on cardiac function has been suggested in patients with diabetes and patients without diabetes. Liraglutide (Victoza) is a GLP-1 analogue developed for the treatment of type 2 diabetes (T2D); however, its impact on cardiac function has not previously been investigated in patients with CHF. This prompted us to investigate whether liraglutide treatment for 24 weeks improves left ventricular ejection fraction (LVEF) in patients with CHF with and without T2D compared with placebo treatment.

Methods and analysis

An investigator-initiated, multicentre, randomised, double-blind, parallel, placebo-controlled intervention trial. In total, 240 patients with CHF (with and without T2D) with LVEF≤45% will be randomised to either subcutaneous injection of liraglutide 1.8 mg or matching placebo once daily for 24 weeks. The effect of liraglutide on left ventricular function will be evaluated by advanced echocardiography, including three-dimensional contrast echocardiography.

Ethics and dissemination

The study will be performed and monitored according to the Good Clinical Practice-International Conference on Harmonisation (GCP-ICH) regulations and conducted according to the principles of the Helsinki Declaration. The Danish Medicines Agency, the local Research Ethics Committee and the Danish Data Protection Agency have approved the study.

Trial registration number

ClinicalTrials.gov Identifier:NCT01472640.