bluuebunny/crossref_metadata_2025 huggingface dataset:
Military noise limits: Design criteria versus operational effectiveness
Authors: Amrein Bruce E. , Letowski Tomasz R.
Published: May 2014

Noise requirements in military environments differ significantly from typical industrial or occupational situations. Both in combat and in training, mission success requires offensive equipment and weapons to be more lethal and survivable than those used by the adversary. Higher muzzle velocities, heavier projectiles, and more powerful engines result in high levels of both steady-state and impulsive noise and an increased risk of hearing loss for the users. Weapons firing can expose the user to more energy in a single event than typically experienced in a working lifetime of occupational exposure. In addition, military operations require effective speech communication while minimizing auditory detection of equipment by the adversary. Producing material suitable for various forms of military operations requires unique design criteria often exceeding civilian national or international standards. To meet these unique and often contradicting requirements, the U.S. military developed a military design standard for noise limits. This standard (MIL-STD-1474) was last revised in 1997. This paper describes the effort of the U.S. Army, Navy, and Air Force to update the standard to permit production and fielding of military systems designed to maximize Warfighter effectiveness, while minimizing hearing damage caused by their use.
Modeling of sound propagation in the vicinity of rigid porous ground by boundary element method
Authors: Wang Yiming , Li Kai Ming
Published: May 2014

A standard boundary integral equation (BIE) technique takes advantage of the well-known Green’s function for the sound fields above an impedance ground. It leads to a simplified solution that enables the development of efficient two-dimensional boundary element numerical codes for computing sound fields above a locally reacting ground. The method is particularly useful if there are multiple reflecting surfaces and the presence of a mixed impedance ground in the proximity of sources and receivers. However, the BIE formulation cannot be applied readily for calculating the sound fields above a non-locally reacting ground because the corresponding Green’s function is generally not available. The so-called two-domain approach was frequently used to model the sound propagation inside the porous material by assuming it as a dissipative fluid medium. By matching the particle velocities and pressures at the interface, a two-domain BIE formulation can be developed for modeling the sound propagation above a rigid porous ground. Use of the two-domain approach has a significant impact on the required computational resources. The current paper presents an alternative method aiming to reduce the computational time by exploring the use of an accurate Green’s function for the development of a BIE formulation above a non-locally reacting ground.
Modeling individual differences in overshoot: Effects of age, hearing loss, and efferent feedback
Authors: Jennings Skyler G. , Ahlstrom Jayne B. , Dubno Judy R.
Published: May 2014

The detection of a short sinusoidal probe in simultaneous masking improves as the probe's onset is delayed from the masker's onset. This “overshoot” may be mediated by the medial olivocochlear (MOC) reflex, whose pathway includes spiral ganglion neurons (SGNs), olivocochlear neurons and the outer hair cells (OHCs). Overshoot was measured in younger adults with normal hearing, older adults with normal hearing, and older adults with hearing loss to test the hypothesis that overshoot decreases as components in the MOC reflex pathway are compromised. Overshoot was significantly reduced in older adults, but only those with hearing loss, which is consistent with overshoot depending primarily on the status of the OHCs and only minimally influenced by age-related reductions in SGNs. Thresholds measured when the probe was near the masker’s onset showed large differences across listeners, resulting in appreciable individual differences in overshoot. Simulations were generated from a computational model of the auditory system to quantify the contributions of cochlear hearing loss, MOC reflex strength, and detection efficiency to individual differences in overshoot. Preliminary results suggest that cochlear hearing loss and detection efficiency explain the largest portion of the variance in overshoot among adults with normal and impaired hearing. [Work supported by NIH/NIDCD.]
Phase effects using chirp maskers
Authors: Klyn Niall A. , Oh Yong Hee , Hoglund Evelyn , Feth Lawrence L.
Published: May 2014

Schroeder-phase maskers appear to interact with the phase curvature of the basilar membrane to produce significantly different amounts of masking depending on the direction of the instantaneous frequency sweep (Oxenham and Dau, 2001). Schroeder-phase maskers may not optimally compensate for the phase-curvature of the basilar membrane, which is not assumed to be linear over its length. This study presents a comparison of masking produced by harmonic complexes that differ only in the phase relationships of their components. Four “chirp” complexes were constructed according to Elberling et al. (2007), with both positive and negative signs, and were compared to Schroeder-phase signals (Smith et al., 1986). Masking observed with pure-tones at three signal frequencies (1, 2, and 4 kHz) and with spectro-temporal burst signals (Hoglund et al., 2013) is reported at two presentation levels (50 and 60 dB SPL). The results are discussed in the context of Schroeder-phase masking and current understanding of the phase-curvature of the human basilar membrane.
A computational study on different flow patterns around the inner hair cell stereocilia
Authors: Prodanovic Srdjan , Gracewski Sheryl M. , Nam Jong-Hoon
Published: May 2014

The mechano-transduction of the mammalian cochlea occurs in the micro-fluid domain between the tectorial membrane and the reticular lamina called the subtectorial space. The subtectorial fluid bathes the bundled stereocilia of the inner hair cells (IHCs). These cells are responsible for the onset of neural impulses in the auditory nerve fibers. Despite the generally accepted postulation that the IHC stereocilia are deflected by shear flow between the two layers, there have been suggestions that other flow modes exist besides the shear flow. We developed a computational model of fluid dynamics in the subtectorial space. The model simulates IHC mechano-transduction excited by different flow patterns. In order to compare different modes of fluid dynamical stimulation, the power efficiency of IHC mechano-transduction was introduced (dissipated power normalized by IHC mechano-transduction current). Besides different flow patterns, the effect of mechanical parameters (such as the gap size between the stereociliary tip and the tectorial membrane, stereociliar bundle stiffness) were investigated. The results demonstrate that the power efficiency for the IHC mechano-transduction depends on the flow pattern in the subtectorial space.
Investigating perceptual structure of concert hall ambiances
Authors: Kanakanahalli Nagendra Aparna , Kim SungYoung
Published: May 2014

With the advent of ultra high definition (UHD) video, a new sound reproduction system incorporating height channel to enhance audio-visual interaction is getting researchers’ attention. To better understand influence of the contents for the height channel(s) on perceived sound quality, the authors have conducted a listening test wherein listeners compared various concert hall ambiances. The authors first recorded the ambiances of a hall at 175 positions (in various heights and positions) using a MIDI-controlled piano. Subsequently we investigated interrelation of ambiances with subordinate objectives: (1) reveal perceptual space of the ambiances and (2) unfold latent yet salient factors. We selected 10 ambiances placed at three-dimensional equidistant from the source as the stimuli. Fifteen musicians participated in a subjective evaluation where they reported perceived dissimilarity between two randomly presented stimuli. The dissimilarity matrices were then analyzed via INDSCAL and the results showed that the stimuli could be coordinated along two bases which corresponded to distance from the source and spectral kurtosis of the stimuli respectively. Finding those salient bases will help assist spatial audio researchers in rendering height ambiances with smaller yet relevant subset of ambiances.
Efficient analysis of dynamic coupling between modifications to complex systems
Authors: Wixom Andrew , McDaniel J. Gregory
Published: May 2014

This paper outlines a strategy for identifying and exploiting the lack of dynamic coupling between potential modifications to a vibroacoustic system. Often a designer develops a set of modifications and wishes to determine those that perform the best relative to some metric, in particular, we consider performance metrics that rely on the steady state forced response of the structure over a frequency band of interest. In this case, the effects of coupling are shown to appear as a force residual and therefore may be neglected if sufficiently small. When modifications are uncoupled from one another, the computational cost of analyzing all possible modified systems can be greatly reduced. For example, if up to 4 of 7 potential modifications are allowed to be applied to a system, there are 98 possible modified systems that need to be analyzed to determine the optimal combination. However if all of the modifications are found to be uncoupled, then only seven modified systems need to be analyzed to generate the results for all possible modified systems. An example problem demonstrates the benefits of uncoupling between modifications.
Effects of talker sex on phonetic convergence in shadowed speech
Authors: Pardo Jennifer , Gash Hannah , Urmanche Adelya , Decker Alexa , Francis Keagan , Wiener Jaclyn , Parker Sara
Published: May 2014

Many studies have reported phonetic convergence during speech shadowing and conversational interaction, with highly variable results. Some of this variability is likely due to effects of talker sex on phonetic convergence. For example, some studies only use a single male model, with both male and female shadowers, while others focus on only male or female talkers. To date, few studies have provided a rigorous investigation of variability across male and female talkers in phonetic convergence. Of these, some studies have found that women converged more than men, while others report the opposite pattern. The current study examined phonetic convergence in a speech shadowing task with 48 talkers (24 female) who shadowed same sex or opposite sex models. The results were analyzed to reveal effects of talker sex and item type (mono- versus bisyllabic words) on measures of phonetic convergence. Because phonetic convergence varies according to the sex of the talker and the model, future studies should employ talker sets that are balanced with respect to talker sex.
Interdependent processing of speech and background noise
Authors: Cooper Angela , Brouwer Susanne , Bradlow Ann R.
Published: May 2014

Speech processing can often take place in listening conditions that involve the mixing of speech and background noise. This study used a speeded classification paradigm to investigate whether background noise is perceptually integrated with indexical (Exp. 1) and phonetic (Exp. 2) dimensions of the speech signal. In each experiment, English listeners classified words along one of two dimensions: noise (pure tone vs. white noise) or a speech dimension, either gender (male vs. female in Exp. 1a), talker identity (Sue vs. Carol in Exp. 1b), or phoneme (/p/ vs. /b/ in Exp. 2), while ignoring the other dimension, which could be held constant (control), co-vary (correlated), or vary randomly (orthogonal). The results indicated that background noise was not completely segregated from speech, even when the two auditory streams were spectrally non-overlapping. Perceptual interference was asymmetric, whereby irrelevant indexical and phonetic variation slowed noise classification to a greater extent than the reverse. This suggests that while context-specific information (e.g., noise) and within-signal speech features are coupled together, they are unevenly weighted during this early stage in processing. This asymmetry may stem from the fact that speech features have greater salience and are thus more difficult to selectively ignore than environmental noise.
Talker's perspective modulates affective coherence in sentence comprehension
Authors: Quene Hugo , Van Leeuwen Anne R. , Van Berkum Jos
Published: May 2014

Does an audible frown or smile affect speech comprehension? Previous research suggests that a spoken word is recognized faster if its audible affect (frown or smile) matches its semantic valence. In the present study, listeners' task was to evaluate the valence of spoken affective sentences. Formants were raised or lowered using LPC to convey an audible smile or frown gesture co-produced with the stimulus speech. A crucial factor was the talker's perspective in the event being described verbally, in either first or third person. With first-person sentences, listeners may relate the talker's affective state (simulated by formant shift) to the valence of the utterance. For example, in “I have received a prize,” a smiling articulation is congruent with the talker having experienced a happy event. However, with third-person sentences (“he has received a prize”), listeners cannot relate the talker's affective state to the described event. (In this example, the talker's affect can be empathic and positive, or envious and negative.) Listeners' response times confirm this hypothesized interaction: congruent utterances are processed faster than incongruent ones, but only for first-person sentences. When listeners evaluate spoken sentences, they combine audible affect, verbal content, as well as perspective, in a sophisticated manner.
Longer words or shorter words: Which one is more effective in distinguishing between self-identified gay and heterosexual male speakers?
Authors: Tracy Erik C.
Published: May 2014

Prior research demonstrated that listeners relied primarily on vowels to determine a male speaker’s sexual orientation (Tracy and Satariano, 2011). Additionally, listeners became more confident in their sexual orientation judgments if the utterance included more vowels (Tracy, 2013). Since multisyllabic utterances also contain more consonants, are listeners’ judgments based on the number of vowels or consonants in an utterance? To investigate this question, monosyllabic, bisyllabic, and trisyllabic words were selected. Within each group of words, the number of phones varied. For example, a trisyllabic word contained either seven phones (“division”) or nine phones (“contribute”). Listeners became more confident of the speaker’s sexual orientation if the word included more vowels. With respect to the monosyllabic and bisyllabic items, listeners were less confident if the number of consonants in the word increased. Ratings were more confident for “have” compared to “help”. The results for the trisyllabic words differed. Listeners became more confident if the word contained more consonants. “Contribute” resulted in more confident ratings than “division”. The results demonstrated that listeners were more confident in the speaker’s sexual orientation if the word included more vowels, but under certain conditions, confidence ratings did not improve if the utterance included additional consonants.
Effects of auditory and visual variability on word learning in children
Authors: Casey Kelly , Marmon Shayna , Butterworth Emily , Katz Elana , Vasil-Dilaj Kristin A. , Theodore Rachel M.
Published: May 2014

One major feat in development is acquiring vocabulary for nouns, a process that necessitates learning a systematic pairing between an auditory and a visual stimulus. This is computationally complex because the acoustic signal produced for a given noun, such as “dog,” varies considerably as do objects in the environment that are given this label. Studies that have separately examined auditory and visual variability suggest that variability in either domain can facilitate word learning. The goal of the current work is to examine simultaneous contributions of auditory and visual variability on word learning. Typically developing infants (15–20 months of age) participate in nine weekly sessions. Each session entails exposure to nouns in a naturalistic play environment where children manipulate visual exemplars while listening to auditory exemplars. Auditory exemplars consist of productions by either ten talkers or by a single talker. Visual exemplars consist of objects that are highly variable or minimally variable in appearance. We measure learning for training exemplars, generalization to novel exemplars, and vocabulary size. Our research questions are (1) does variability in the auditory domain alone facilitate word learning as has been shown for visual variability, (2) to what degree does simultaneous variability in both modalities influences noun learning.
Voice quality variation across gender identities
Authors: Becker Kara , Khan Sameer ud Dowla , Zimman Lal
Published: May 2014

While several studies of the phonetics of American English make reference to general features of “women's speech” and “men's speech,” no large-scale acoustic or articulatory study has established the actual range and diversity of phonetic variation along gender identities, encompassing different sexual orientations, regional backgrounds, and socioeconomic classes. The current study explores the acoustic and articulatory phonetic features related to gender, particularly focusing on voice quality, e.g., creaky and breathy phonation. Subjects identifying with a range of gender and other demographic identities were audio recorded producing the Rainbow Passage as well as wordlists targeting variation in vowel quality. Simultaneously, electroglottographic (EGG) readings were taken and analyzed for voice quality. Subjects were then asked to rate recordings of other people’s voices to identify the personal characteristics associated with the acoustic reflexes of phonation; in the final task, subjects were also explicitly asked about their language ideologies as they relate to gender. Thus, the current study explores the relation between gender identity and phonetic features, measured acoustically, articulatorily, and perceptually. This work is currently underway and preliminary results are being compiled at this time.
Acoustic separability of Mandarin tonal categories in careful and conversational speech
Authors: Brenner Daniel
Published: May 2014

Previous work has found that tonal categories in conversation are realized with mostly much weaker acoustic cues than in careful speech. For example, pitch curves become flatter (less curved), more level (shallower slopes), and more centralized (closer to the speaker’s mean speaking pitch) in conversation on average relative to careful speech, and also more variable. At the same time, a few cues appear to change direction (e.g., the pitch range of tone 4 is much larger than that of tone 3 in careful speech, but is far shorter in conversation), or become acoustically salient to categories in conversation only (pilot results suggest that tone 3 is especially short in duration in conversation). The present project incorporates tonal context, and bigram syllable- and tone- frequencies into a model of the differentiability of second-syllable tonal categories in two-syllable Mandarin words in conversation. This model approximates the extent to which tonal category can be determined from available acoustic cues in conversation while accounting for co-occurrence frequencies.
Accuracy of six techniques for measuring formants in isolated words
Authors: Shadle Christine H. , Nam Hosung , Whalen D. H.
Published: May 2014

In previous work comparing formant measurements of synthetic vowels, manual measurements and four of the six algorithms tested were shown to have large errors and be biased by fundamental frequency (F0). In this study, natural speech recorded by five speakers (2 female, 3 male) was used to provide a more realistic test. The context /hVd/ was used with vowels V = {/i, ae, u, a/}, in which formant frequencies could be expected to be relatively constant; declarative intonation was elicited so that F0 would be falling throughout the vowel, eliciting evidence of F0 bias. Formants were estimated throughout using LPC Burg, LP closed-phase covariance, Weighted Linear Prediction with Attenuated Main Excitation (WLP-AME) [Alku et al., JASA 134(2), 1295–1313 (2013)], AVG, CEPS, and reassigned spectrogram with pruning (RS). The LPC methods show evidence of F0 bias, with WLP-AME having the smallest errors (Alku et al. compared it to many LPC variants, including DAP); RS has the smallest errors overall, but is not fully automatic. Accuracy during vocal fry and for low vs. high F0s will be discussed. As with synthetic speech, WLP-AME can be recommended as the analysis of choice until RS becomes more automatic and less subjective. [Work supported by NIH.]
Temporal stability of long-term measures of fundamental frequency
Authors: Arantes Pablo , Eriksson Anders
Published: May 2014

We investigated long-term mean, median, and base value of the voice fundamental frequency (F0) to estimate how long it takes their variability to stabilize. That information can be useful in the development of F0 contour normalization and forensic applications. Change point analysis was used to locate changes in underlying variance in the mean, median, and base value time-series. In one experiment, stabilization points were calculated in recordings of the same text spoken in 26 languages. Average stabilization points are 5 s for base value and 10 s for mean and median. Variance after the stabilization point was reduced around 40 times for mean and median and more than 100 times for the base value. In another experiment, four speakers read two different texts each. Stabilization points for the same speaker across the texts do not exactly coincide as would be ideally expected. Average point dislocation is 2.5 s for the base value, 3.4 for the median, and 9.5 for the mean. After stabilization, differences in the three measures obtained from the two texts are 2% on average across speakers. Present results show that stabilization points in long-term measures of F0 occur earlier than suggested in the previous literature.
Leveraging spatial diversity to mitigate interference in underwater acoustic communication networks
Authors: McGee James , Swaszek Peter , Catipovic Josko
Published: May 2014

Many acoustic communication channels suffer from interference which is neither narrowband nor impulsive. This relatively long duration partial band interference can be particularly detrimental to system performance. To address the problem of underwater communications over a time-varying multipath channel in the presence of partial band interference, we examine a receiver which leverages the spatial diversity implicit in a network of geographically distributed hydrophones due to the slow speed of sound propagation. The network consists of multiple cabled hydrophones which receive communication signals from multiple users in addition to interfering signals from active sonars and marine mammals. The partial band interference corrupts different portions of the received signal depending on the relative position of the interferers, information source and receivers. The need for explicit time alignment and channel compensation due to the differing propagation paths between sources and receivers complicates combining the received signals. After surveying recent work in interference mitigation and orthogonal division multiplexing as background motivation, we examine the problem of combining information from such differentially corrupted signals through simulation.
A Comparison of Ballet Dancers With Different Level of Experience in Performing Single-Leg Stance on Retiré Position
Authors: Lin Chia-Wei , Lin Cheng-Feng , Hsue Bih-Jen , Su Fong-Chin
Published: May 2014

The purpose of the current study was to evaluate the postural stability of singleleg standing on the retiré position in ballet dancers having three different levels of skill. Nine superior experienced female ballet dancers, 9 experienced, and 12 novice dancers performed single-leg standing in the retiré position. The parameters of center of pressure (COP) in the anterior-posterior and medial-lateral directions and the maximum distance between COP and the center of mass (COM) were measured. The inclination angles of body segments (head, torso, and supporting leg) in the frontal plane were also calculated. The findings showed that the novice dancers had a trend of greater torso inclination angles than the experienced dancers but that the superior experienced dancers had greater maximum COM-COP distance in the anterior-posterior direction. Furthermore, both experienced and novice dancers had better balance when standing on the nondominant leg, whereas the superior experienced dancers had similar postural stability between legs. Based on the findings, ballet training should put equal focus on both legs and frontal plane control (medial-lateral direction) should be integrated to ballet training program.
Many Fences Make Better Neighbors
Authors: Zemp Franz J. , Waterhouse Christopher C. M. , Kubes Paul
Published: May 2014

Phagocytic Kupffer cells in the liver act as a firewall that captures commensal bacteria that have breached the barrier of the gut mucosa (Balmer
et al
.
,
this issue).
Altered Oral Viral Ecology in Association with Periodontal Disease
Authors: Ly Melissa , Abeles Shira R. , Boehm Tobias K. , Robles-Sikisaka Refugio , Naidu Mayuri , Santiago-Rodriguez Tasha , Pride David T.
Published: May 2014

The human oral cavity is home to a large and diverse community of viruses that have yet to be characterized in patients with periodontal disease. We recruited and sampled saliva and oral biofilm from a cohort of humans either periodontally healthy or with mild or significant periodontal disease to discern whether there are differences in viral communities that reflect their oral health status. We found communities of viruses inhabiting saliva and the subgingival and supragingival biofilms of each subject that were composed largely of bacteriophage. While there were homologous viruses common to different subjects and biogeographic sites, for most of the subjects, virome compositions were significantly associated with the oral sites from which they were derived. The largest distinctions between virome compositions were found when comparing the subgingival and supragingival biofilms to those of planktonic saliva. Differences in virome composition were significantly associated with oral health status for both subgingival and supragingival biofilm viruses but not for salivary viruses. Among the differences identified in virome compositions was a significant expansion of myoviruses in subgingival biofilm, suggesting that periodontal disease favors lytic phage. We also characterized the bacterial communities in each subject at each biogeographic site by using the V3 hypervariable segment of the 16S rRNA and did not identify distinctions between oral health and disease similar to those found in viral communities. The significantly altered ecology of viruses of oral biofilm in subjects with periodontal disease compared to that of relatively periodontally healthy ones suggests that viruses may serve as useful indicators of oral health status.

IMPORTANCELittle is known about the role or the constituents of viruses as members of the human microbiome. We investigated the composition of human oral viral communities in a group of relatively periodontally healthy subjects or significant periodontitis to determine whether health status may be associated with differences in viruses. We found that most of the viruses present were predators of bacteria. The viruses inhabiting dental plaque were significantly different on the basis of oral health status, while those present in saliva were not. Dental plaque viruses in periodontitis were predicted to be significantly more likely to kill their bacterial hosts than those found in healthy mouths. Because oral diseases such as periodontitis have been shown to have altered bacterial communities, we believe that viruses and their role as drivers of ecosystem diversity are important contributors to the human oral microbiome in health and disease states.
Post occlusive left atrial appendage thrombosis with extension into the left atrium
Authors: Shalaby Alaa , Refaat Marwan , Lacomis Joan , Zenati Marco
Published: May 2014

A 67-year-old man underwent left atrial appendage (LAA) exclusion concomitant with mitral valve surgery and radiofrequency ablation maze procedure. On transoesophageal echocardiography anticipating ablation for left atrial tachycardia, an echodense thrombus was visualised in the LAA location with apparent intracavitary extension into the left atrium. Based on CT imaging findings, the echo represented thrombosis of a large left atrial appendage with probable extension into the left atrium.
Giant recurrent intrathoracic goitre treated by clamshell thoracotomy and reverse sternotomy
Authors: Komninos Georgios , Galata’ Gabriele , Schulte Klaus-Martin
Published: May 2014

A 59-year-old man with a giant recurrent intrathoracic goitre was admitted for completion thyroidectomy for recurrent severe retrosternal pain. The patient had undergone a cervical thyroidectomy elsewhere 13 years earlier, during which only the cervical part of the goitre had been resected. Owing to the previous operation with an expected scar around the innominate vein, and the goitre's size and localisation obstructing the upper chest aperture, we chose an alternate access. Clamshell thoracotomy with reverse sternotomy allows central vascular control and excision of large goitres bypassing predictable problems at the cervicothoracic junction. Surgery was performed with minimal blood loss and with excellent functional outcome. The described access adds to the repertoire to deal with this unusual situation.
Spontaneous fracture of diaphyseal stem of S-ROM femoral prosthesis
Authors: Pearce Simon , Jenabzadeh Amir-Reza , Walter William L , Gillies Ronald Mark
Published: May 2014

We present two cases of spontaneous fractures of the S-ROM femoral stem prosthesis implanted by different surgeons within 5 years of implantation. Both the stems fractured in the mid-distal stem at the junction of the main body and the slotted portion. Both fractures affected the posterior tine only. Our aim in publication is to ensure that this is an isolated problem and not an under-reported phenomenon. We are not aware of any previous reports of spontaneous fracture of the distal stem.
Acute Marchiafava-Bignami disease: clinical and serial MRI correlation
Authors: Kakkar Chandan , Prakashini Koteshwara , Polnaya Ashwin
Published: May 2014

Marchiafava-Bignami disease (MBD) is a form of toxic demyelinating disease more often seen in chronic alcoholics. The disease process typically involves the corpus callosum and clinically often presents with altered sensorium, neurocognitive defects or seizures with acute cases often deteriorating to comatose state. The death rate is high. We report a rare case of MBD with complete clinical recovery. A 50-year-old male patient presented in an unconscious state and underwent MRI of the brain which showed significant lesions involving the corpus callosum. Following treatment with thiamine and supportive therapy, he improved clinically and a follow-up MRI revealed significant resolution of the earlier lesions. Diffusion-weighted MRI showed the changes more conspicuously as compared with conventional imaging. The clinical resolution corresponded well with the MRI pattern. The case highlights that diffusion-weighted MRI is an extremely useful tool in evaluation and prognostication of MBD.
One lump or two? Concomitant Leydig cell tumour and paratesticular leiomyoma in an adult man
Authors: Lin Diwei , Tan Amanda Jia Hui , Power Theresa , Singh-Rai Rajinder
Published: May 2014

We present the first reported case of a concomitant Leydig cell tumour (LCT) and paratesticular leiomyoma in an adult man with a history of bilateral cryptorchidism. An 80-year-old man presented with a 2-month history of a left testicular lump associated with mild discomfort and a gradual increase in size on a background of bilateral cryptorchidism requiring multiple orchidopexy procedures as a child. Ultrasound confirmed a lesion suspicious for malignancy and he proceeded to a left radical orchidectomy. Histopathological assessment of the left testis revealed a concomitant testicular LCT with rare malignant features and paratesticular leiomyoma.
Hypoglycaemia in a 94-year-old man without diabetes
Authors: Mullens Dustin James , Shubrook Jay H
Published: May 2014

Recognising a hypoglycaemic event in a person without a history of diabetes poses quite a challenge. A 94-year-old man without diabetes in an extended care facility (ECF) was found unconscious and non-responsive with a glucose level of 30 mg/dL. The patient required multiple resuscitations with glucagon and intravenous glucose before his blood glucose stabilised. Ultimately the accidental administration of a sulfonylurea was found to be responsible for the event. The patient fortunately recovered after 5 days of hospitalisation. Adults aged 65 years and older carry a significantly higher risk of serious adverse drug events (ADEs) requiring hospitalisation. Antidiabetic drugs cause nearly one-quarter of all hospitalisations from ADEs, with more than 99% due to unintentional overdose. To truly optimise patient care, providers must be cognizant of the risks associated with diabetes management to better monitor and prevent future occurrence of such taxing events.
False-positive tuberculous meningitis due to laboratory contamination: importance of a holistic clinical evaluation
Authors: Vallabhajosyula Saraschandra , Vivekanandan Renuga , Horowitz Edward A
Published: May 2014

Incidence of tuberculosis in Nebraska is 1.9/100 000 people. Tuberculous meningitis is rare and comprises 1% of extrapulmonary tuberculosis. An elderly Caucasian man presented with fever, headache, altered mentation and a history of tick bite. Cerebrospinal fluid (CSF) analysis showed negative cultures and the patient was treated empirically for tickborne illness. Forty-five days later, CSF nucleic acid amplification test (NAAT) was positive for tuberculosis. On readmission, repeat neurological examination and CSF analysis were benign and the patient was not offered antituberculous treatment. Genotype investigation of the culture and NAAT specimen by the Center for Disease Control confirmed laboratory contamination. The literature reports an incidence of 2–4% for false-positive tuberculosis cultures. Contaminated devices, clerical errors and laboratory errors have been implicated. Laboratory contamination results in smear-negative culture-positive cases. Epidemiological investigation with genotype testing is confirmatory. Detailed clinical assessment with good clinical and laboratory communication and frequent laboratory surveillance is advocated to mitigate these cases.
Improving the quality of patient handover on a surgical ward
Authors: Bradley Alison
Published: May 2014

The European Working Time Directive means safe patient hand over is imperative. It is the responsibility of every doctor and an issue of patient safety and clinical governance [1]. The aims of this project were to improve the quality of patient handover between combined assessment unit (CAU) and surgical ward FY1 doctors.

The Royal College of Surgeons England (RCSEng) guidelines on surgical patient handover [1] were used as the standard. Data was collected throughout November 2013. A handover tool was then introduced and attached to the front of patient notes when a patient was transferred from CAU to the surgical ward. The doctor handing over the patient and the ward doctor receiving the handover signed this document. Policy was also changed so that handover should take place once the patient had received senior review on the CAU and was deemed appropriate for transfer to the surgical ward. Data from the handover tool was collated and checked against the list of surgical admission for February 2014.

The number of patients handed over improved from 15 % to 45%. The quality of patient handover also improved. 0 patient handovers in November 2013 included all of the information recommended by the RCSEng guidelines. 100% of the patient handovers in February 2014 contained all the recommended information.

Introduction of a handover tool and formalisation of timing of patient handover helped to improve quality and number of patients being handed over. Further work needs to be done to improve safe handover of surgical patients, particularly out of hours.
Domestic violence in a UK abortion clinic: anonymous cross-sectional prevalence survey
Authors: Motta Silvia , Penn-Kekana Loveday , Bewley Susan
Published: May 2014

Objective

To measure the prevalence of domestic violence (DV) experienced by women seeking termination of pregnancy (TOP) in a UK abortion clinic.

Methods

A cross-sectional anonymous questionnaire survey of all women aged over 16 years accessing a TOP clinic in inner London between 20 May 2012 and 2 July 2012. The main outcome measures were: distribution of questionnaires, response rate, lifetime prevalence of abuse, past-year prevalence of physical and sexual abuse, prevalence of physical abuse during current pregnancy, relationship of lifetime abuse to number of terminations, and receptivity to DV services.

Results

Questionnaires were distributed to 46% (383/828) of women accessing the clinic. Response rate was 50% (190/383). Lifetime prevalence of abuse was 16%. Past-year prevalence of physical abuse was 11% and sexual abuse was 4%. Prevalence of physical abuse during the current pregnancy was 4%. Prevalence of lifetime abuse was lower in women having a first termination (12%) versus one (20%) or two or more previous terminations (24%), although this was not statistically significant (p=0.192). The majority (75%) of participants expressing an opinion on the possibility of having a support service for DV in the abortion clinic setting were positive, unrelated to their personal experience, but some concerns were raised about implementation.

Conclusions

In order to provide effective support for women, services require a needs assessment of their local population. Asking women presenting for abortion about DV, even anonymously, is challenging but feasible. Future work should be directed to women's unmet safety needs.
LOW POWER FRACTIONAL-N FREQUENCY DIVIDER WITH IMPROVED RESOLUTION
Authors: ZACKRIYA V. MOHAMMED , REUBEN JOHN , HARSH ASHIM , KITTUR HARISH M.
Published: May 2014

Multiple clock domain (MCD) systems have different blocks/IP cores operating at different frequencies. These different clocks are generated from a high frequency clock usually by integer division. Fractional-N frequency dividers (FFDs) are needed when the clock required by a block in MCD system is not possible to be derived by simple integer division. In this paper, we present such a FFD with an improved resolution of (1/8). Post layout simulation results after parasitic RC extraction in the 90-nm technology node show that our FFD is able to fractionally divide signals upto 2 GHz frequency with an average error of 0.11% in division ratio even with 2.5° phase error at the input. Our FFD consumes 754 μW when fractionally dividing a 2 GHz signal with a resolution of (1/8).
Endogenous Collateral Constraints and the Leverage Cycle
Authors: Fostel Ana , Geanakoplos John
Published: May 2014

We review the theory of leverage developed in collateral equilibrium models with incomplete markets. We explain how leverage tends to boost asset prices and create bubbles. We show how leverage can be endogenously determined in equilibrium and how it depends on volatility. We describe the dynamic feedback properties of leverage, volatility, and asset prices, in what we call the leverage cycle, and show how it differs from a credit cycle. We also describe some cross-sectional implications of multiple leverage cycles, including contagion, flight to collateral, and swings in the issuance volume of the highest-quality debt.
Training status diverges muscle diacylglycerol accumulation during free fatty acid elevation
Authors: Chow Lisa S. , Mashek Douglas G. , Austin Erin , Eberly Lynn E. , Persson Xuan-Mai , Mashek Mara T. , Seaquist Elizabeth R. , Jensen Michael D.
Published: May 2014

How endurance training alters muscle lipid metabolism while preserving insulin sensitivity remains unclear. Because acute free fatty acid (FFA) elevation by lipid infusion reduces insulin sensitivity, we hypothesized that training status would alter accumulation of muscle triacylglycerol (TAG), diacylglycerol (DAG), ceramide, and acylcarnitine during acute FFA elevation. Trained ( n = 15) and sedentary ( n = 13) participants matched for age, sex, and BMI received either a 6-h infusion of lipid (20% Intralipid at 90 ml/h) or glycerol (2.25 g/100 ml at 90 ml/h) during a hyperinsulinemic euglycemic clamp. Muscle biopsies were taken at 0, 120, and 360 min after infusion initiation to measure intramyocellular concentrations of TAG, DAG, ceramides, and acylcarnitines by liquid chromatography-tandem mass spectrometry. Trained participants had a higher V̇o2 maxand insulin sensitivity than sedentary participants. The lipid infusion produced a comparable elevation of FFA (594 ± 90 μmol/l in trained, 721 ± 30 μmol/l in sedentary, P = 0.4) and a decline in insulin sensitivity (−44.7% trained vs. −47.2% sedentary, P = 0.89). In both groups, lipid infusion increased the linoleic and linolenic acid content of TAG without changing total TAG. In the sedentary group, lipid infusion increased total, oleic, and linoleic acid and linolenic acid content of DAG. Regardless of training status, lipid infusion did not alter total ceramide, saturated ceramide, palmitoyl-carnitine, or oleoyl-carnitine. We conclude that during acute FFA elevation, trained adults have a similar decline in insulin sensitivity with less accumulation of muscle DAG than sedentary adults, suggesting that lipid-induced insulin resistance can occur without elevation of total muscle DAG.
Study on the Microstructure and Electrical Properties of Boron and Sulfur Codoped Diamond Films Deposited Using Chemical Vapor Deposition
Authors: Jing Zhang , Rongbin Li , Xianghu Wang , Xicheng Wei
Published: May 2014

The atomic‐scale microstructure and electron emission properties of boron and sulfur (denoted as B‐S) codoped diamond films grown on high‐temperature and high‐pressure (HTHP) diamond and Si substrates were investigated using atom force microscopy (AFM), scanning tunneling microscopy (STM), secondary ion mass spectroscopy (SIMS), and current imaging tunneling spectroscopy (CITS) measurement techniques. The films grown on Si consisted of large grains with secondary nucleation, whereas those on HTHP diamond are composed of well‐developed polycrystalline facets with an average size of 10–50 nm. SIMS analyses confirmed that sulfur was successfully introduced into diamond films, and a small amount of boron facilitated sulfur incorporation into diamond. Large tunneling currents were observed at some grain boundaries, and the emission character was better at the grain boundaries than that at the center of the crystal. The films grown on HTHP diamond substrates were much more perfect with higher quality than the films deposited on Si substrates. The local I-V characteristics for films deposited on Si or HTHP diamond substrates indicate n‐type conduction.
Removing and Recovering Phosphate from Poultry Wastewater Using Amorphous Ceramics
Authors: Xie Youhui , Li Qin , Zhao Xianzhi , Luo Yi , Wang Yangming , Peng Xiangwei , Wang Qigui , Su Jian , Lu Yin
Published: May 2014

A novel and effective technique for phosphate from poultry wastewater was developed using amorphous ceramics. Amorphous ceramics, which showed high performance for phosphate removal and recovery from poultry wastewater, were synthesized using unlimitedly available, inexpensive materials such as silica fume and lime. Dissolved phosphate in poultry wastewater can be deposited as a solid on the surface of amorphous ceramics. Phosphate content on the surface of amorphous ceramics could reach 14.20%. The phosphate removal and recovery process and mechanism was revealed by a series of characterizations, such as XRD, FESEM, BET, and so on. The present study demonstrated that amorphous ceramics have great potential as a novel, beneficial material for removing and recovering phosphate from poultry wastewater.
Histologic Changes of Implanted Gore Bio-A in an Experimental Animal Model
Authors: Yeo Kwan Koo , Park Tae Hwan , Park Jin Hyuk , Chang Choong Hyun , Kim June-kyu , Seo Sang Won
Published: May 2014

Gore Bio-A has been reported to be an ideal synthetic bioabsorbable scaffold material for hernia repair. The purpose of this study was to determine the effectiveness of Gore Bio-A in soft tissue augmentation. Six New Zealand white rabbits were used in the study. Five subcutaneous pockets were created on the back of the rabbit, and20×20 mm sized square shaped Gore Bio-A sheets, each 1.5 mm, 3 mm, 4.5 mm, 6 mm, and 7.5 mm in thickness, were implanted into each pocket (1 layer to 5 layers). To analyze the morphologic and histologic changes, the implants were harvested 1, 3, and 6 months after implantation. Following the gross analysis, absorption rate was accelerated with increased implant duration and decreased thickness. Histological analysis of the implants demonstrated progressive neovascularization, fibroblast infiltration, and neocollagenation over time. Six months after implantation, Gore Bio-A was almost absorbed and degenerated, not maintaining its volume. Based on this study, Gore Bio-A was revealed as a biocompatible material; however, it is not suitable for soft tissue augmentation because it is absorbed in the process of changing into soft tissue without maintaining its own volume. Therefore, this material is incomplete and needs more study to overcome this limitation.
Dissipative Delay‐Feedback Control for Nonlinear Stochastic Systems with Time‐Varying Delay
Authors: Chen Guici , Zhou Jianzhong , Zhang Yongchuan
Published: May 2014

The dissipative delay‐feedback control problems for nonlinear stochastic delay systems (NSDSs) based on dissipativity analysis are studied in this paper. Based on the Lyapunov stability theory and stochastic analysis technique,
both delay‐independent and delay‐dependent dissipativity criteria are established as linear matrix inequalities‐ (LMIs‐) based feasibility tests. The obtained results in this paper for the nominal systems include the available results on
H∞ approach and passivity for stochastic delay systems as special cases. The delay‐dependent feedback controller is designed by considering the relationship among the time‐varying delay, its lower and upper bound, and its differential
without ignoring any terms, which effectively reduces the conservative. A numerical example is given to illustrate the theoretical developments.
The Technological Development of Minimally Invasive Spine Surgery
Authors: Snyder Laura A. , O'Toole John , Eichholz Kurt M. , Perez-Cruet Mick J. , Fessler Richard
Published: May 2014

Minimally invasive spine surgery has its roots in the mid-twentieth century with a few surgeons and a few techniques, but it has now developed into a large field of progressive spinal surgery. A wide range of techniques are now called “minimally invasive,” and case reports are submitted constantly with new “minimally invasive” approaches to spinal pathology. As minimally invasive spine surgery has become more mainstream over the past ten years, in this paper we discuss its history and development.