bluuebunny/crossref_metadata_2025 huggingface dataset:
Cognitive functioning of adults with Noonan syndrome: a case–control study
Authors: Wingbermühle E. , Roelofs R. L. , van der Burgt I. , Souren P. M. , Verhoeven W. M. A. , Kessels R. P. C. , Egger J. I. M.
Published: July 2012

Noonan syndrome (NS) is a genetic disorder characterised by short stature, facial dysmorphia, congenital heart defects and mildly lowered intellectual abilities. Research has mainly focused on genetic and somatic aspects, while intellectual and cognitive functioning has been documented scarcely. Also, to date studies have been primarily performed in children. This is the first study in which functioning within the major cognitive domains is systematically evaluated in a group of adults with NS and compared with a control group. Extensive neuropsychological assessment, including the domains intelligence, speed of information processing, memory (working memory, immediate recall and delayed recall), executive function and visuoconstruction, was performed in a sample of 42 patients with NS and 42 healthy controls, matched on age, sex and education level. In addition, subjective cognitive complaints were assessed with self‐report questionnaires. On the domain speed of information processing patients performed worse than controls (P < 0.05). Furthermore, except for slightly better results on delayed recall in the patients with NS (P < 0.05), none of the other cognitive domains showed between‐group differences. On the questionnaires, patients reported substantially more complaints about their own cognitive abilities than controls (P < 0.05). A lowered speed of information processing and relatively intact functioning in other cognitive domains characterises the cognitive profile of adult patients, in contrast to previous findings in children with NS, who seem to have more generalised cognitive deficits.
Definitions of the physical properties of pressure ulcers and characterisation of their regional variance
Authors: Mizokami Fumihiro , Furuta Katsunori , Utani Atsushi , Isogai Zenzo
Published: July 2012

A pressure ulcer is a localised injury of the skin and underlying tissue that usually develops over a bony prominence. A decrease in the pressure over the bony prominence effectively prevents pressure ulcers; however, no studies have systematically assessed the physical properties of existing pressure ulcers. To characterise pressure ulcers, we established new terminology that clarifies the physical properties of pressure ulcers: wound mobility was defined as movement using the bony prominence as a predefined specific marker, and wound deformity was defined as a change in the three‐dimensional shape of the wound. Observational studies using this terminology showed that the distinct physical properties of pressure ulcers depend on the site of development and the wound depth according to the National Pressure Ulcer Advisory Panel criteria. Most grade IV sacrum pressure ulcers exhibited mobility and deformity. Superficial sacrum pressure ulcers below grade II showed only mobility. In contrast, foot pressure ulcers did not exhibit mobility or deformity. We propose a new concept, ‘wound physical property’, for understanding the unique pathogenesis of pressure ulcers.
Blood transfusion and Jehovah's Witnesses revisited: Implications for surgeons
Authors: Wong David S.Y.
Published: July 2012

The refusal of blood transfusion and blood products is becoming more common. Jehovah's Witnesses are notably known to be deeply convicted in this doctrine. Doctors are bound in their practice by codes of ethics as to their professional conduct. When it comes to lifesaving situations where transfusion is absolutely needed, a conflict arises between the doctor's professional duty to save lives and the right of autonomy of the patient to his body. This article discusses the background of this conflict, suggested solutions, the legal precedents and how the authorities can help to handle this difficult dilemma for the frontline clinician, with specific reference to the existing situation in Hong Kong.
On the origin of a highly dispersed coherent radio burst
Authors: Keane E. F. , Stappers B. W. , Kramer M. , Lyne A. G.
Published: July 2012

We discuss the possible source of a highly dispersed radio transient discovered in the Parkes Multibeam Pulsar Survey (PMPS). The pulse has a dispersion measure of 746 cm−3 pc, a peak flux density of 400 mJy for the observed pulse width of 7.8 ms and a flat spectrum across a 288-MHz band centred on 1374 MHz. The flat spectrum suggests that the pulse did not originate from a pulsar, but is consistent with radio-emitting magnetar spectra. The non-detection of subsequent bursts constrains any possible pulsar period to ≳1 s, and the pulse energy distribution to being much flatter than typical giant pulse emitting pulsars. The burst is also consistent with the radio signal theorized from an annihilating mini black hole. Extrapolating the PMPS detection rate provides a limit of ΩBH ≲ 5 × 10−14 on the density of these objects. We investigate the consistency of these two scenarios, plus several other possible solutions, as potential explanations to the origin of the pulse, as well as for another transient with similar properties: the Lorimer burst.
Analytical Study of Airflow Induced by Barometric Pressure and Groundwater Head Fluctuations in a Two‐Layered Unsaturated Zone
Authors: Song Jin‐Ying , Li Hailong , Wan Li
Published: July 2012

A study on subsurface airflow plays a vital role in quantifying the effectiveness of natural attenuation of volatile organic compounds (VOCs) or in determining the need of engineering systems (e.g., soil vapor extraction of VOCs). Here, we present a new analytical solution for describing the subsurface airflow induced by barometric pressure and groundwater head fluctuations. The solution improves a previously published semi‐analytical solution into a fully explicit expression and can save much computation efforts when it was used to estimate the soil permeability and porosity, which was demonstrated by a hypothetical example. If the groundwater head and barometric pressure fluctuations have the same frequency and the same order of magnitude for the amplitudes, each or the combination of both fluctuations will generate the air exchange volumes of the same order of magnitude through the ground surface. Particularly, the air exchange volume caused by the combined fluctuations increases with the upper layer's permeability and lower layer's porosity and decreases with the phase difference between these two fluctuations, fluctuation frequency, and the upper layer's thickness. The air exchange volume may decrease quickly to zero essentially when the upper layer's permeability decreases 10‐fold and decrease fourfold to fivefold when the phase difference decreases from π to zero.
Dementia in Patients Hospitalized with Stroke: Rates, Time Course, and Clinico-Pathologic Factors
Authors: Pendlebury Sarah T.
Published: July 2012

Stroke is a risk factor for dementia and dementia predisposes to stroke. Dementia prevalence in subjects with stroke is comparable with that seen in stroke-free subjects who are 10 years older. Although overall there is heterogeneity between studies of prestroke and poststroke dementia, stratifying by study method and clinical criteria (e.g. inclusion/exclusion of prestroke dementia, first ever vs. any vs. recurrent stroke) results in reasonably consistent estimates. Pooled dementia rates from studies of consecutive patients hospitalized with stroke indicate that around 10% have dementia prior to first stroke and 10% have new dementia in the first year after first-ever stroke with highest rates (over 30%) seen after recurrent stroke. After the immediate high-risk poststroke period, rates of new incident dementia are lower but remain elevated at around four times the background risk. Factors associated with prestroke and poststroke dementia are broadly similar but age, medial temporal lobe atrophy, female sex, and family history are more strongly associated with prestroke dementia suggesting a greater role for degenerative pathology. Poststroke dementia is associated with factors indicating a reduced cognitive reserve (prestroke cognitive decline, premorbid disability, low education, white matter disease, and atrophy) and is also strongly associated with stroke factors (lesion size, multiple lesions, and stroke recurrence) and complications of stroke (delirium, seizures, hypotension, systemic illness and incontinence) indicating the likely impact of optimal acute stroke care and secondary prevention in reducing the burden of dementia. Future studies are needed to clarify the interaction between degenerative, vascular, and systemic processes in the development of stroke-associated dementia.
Erythema multiforme and epitheliotropic T‐cell lymphoma in the oral cavity of dogs: 1989 to 2009
Authors: Nemec A. , Zavodovskaya R. , Affolter V. K. , Verstraete F. J. M.
Published: July 2012

Objectives

To describe the clinical signs, major laboratory findings, diagnostic procedures and outcome in dogs with erythema multiforme or epitheliotropic T‐cell lymphoma of the oral cavity.

Methods

Retrospective analysis identified 14 client‐owned dogs with erythema multiforme or epitheliotropic T‐cell lymphoma of the oral cavity. Histological changes were combined with immunohistochemistry and clonality testing data in selected cases, and a clinical follow‐up was acquired.

Results

Ulcerative stomatitis with no significant or only minor abnormalities on haematology and serum biochemistry panels was common. Histological features were diagnostic in seven cases. The use of immunohistochemistry distinguished the two diseases in an additional three cases. In four cases, the diagnosis remained questionable, and clonality testing for T‐cell receptor gamma gene rearrangement helped confirm erythema multiforme in one case. Clinical follow‐up revealed erythema multiforme in two and epitheliotropic T‐cell lymphoma in one of the remaining questionable cases.

Clinical Significance

Erythema multiforme and epitheliotropic T‐cell lymphoma may affect, but are rarely limited to the oral cavity of dogs, and they usually present as stomatitis. Histological features alone are not always diagnostic. Immunohistochemistry and clonality testing may assist in the differentiation between the two, but in ambiguous cases, repeated biopsy and clinical follow‐up are essential.
Total hip replacement for the treatment of atraumatic slipped femoral capital epiphysis in dogs
Authors: Gemmill T. J. , Pink J. , Clarke S. P. , McKee W. M.
Published: July 2012

Objectives

To evaluate dogs diagnosed with slipped femoral capital epiphysis which were treated by total hip replacement.

Methods

Clinical and radiographic records of consecutive cases of slipped femoral capital epiphysis treated by total hip replacement were reviewed. Longer‐term follow‐up was by owner questionnaire.

Results

Fifteen cases were identified; 14 were affected unilaterally, 1 bilaterally. Median age at presentation was 13 months (range 6 to 30); median weight was 35 kg (range 10 to 66). Radiographically, proximal femoral sclerosis was evident in 13 of 16 hips. Thirteen hybrid and three cemented total hip replacements were performed. One dog had a stem complication five months postoperatively necessitating explantation. All other total hip replacements remained functional. At four weeks postoperatively lameness and pain scores were improved in all cases. Fourteen total hip replacements were examined after three months. Lameness was mild in 2 limbs and absent in 12; pain on manipulation was not apparent in any case. Significant radiographic complications were not encountered. Telephone questionnaires were performed for 14 cases (15 total hip replacements) at a median of 22 months postoperatively (range 8 to 45). Lameness was reportedly absent for 12 limbs and intermittent in 3. All owners felt that their dogs’ quality of life was good.

Clinical Significance

Total hip replacement can be a successful technique to treat slipped femoral capital epiphysis.
Factors influencing diagnosis of colorectal cancer: A hospital‐based survey in China
Authors: Deng Shang Xin , An Wei , Gao Jie , Yin Jie , Cai Quan Cai , Yang Ming , Hong Shang You , Fu Xin Xin , Yu En Da , Xu Xiao Dong , Zhu Wei , Li Zhao Shen
Published: July 2012

Objective

To investigate the diagnostic status of colorectal cancer (CRC) and the influence of early diagnosis and cancer stage in a tertiary care hospital in China.

Methods

Face‐to‐face interviews were conducted in 364 consecutive CRC patients who had never participated in CRC screening. Initial symptoms, diagnosis and treatment delay were determined using a questionnaire. Factors influencing diagnostic status were analyzed using univariate analysis and logistic regression model.

Results

A total of 307 patients were enrolled, in which 128 were with colon cancer and 179 with rectal cancer. The duration of diagnosis delay was significant longer than that of treatment delay. Unlike rectal cancer, colon cancer was likely to be treated at an advanced stage with a short interval between symptom onset and treatment. Colon cancer patients with a history of biliary tract or gallbladder stones, aged ≥ 50 years and with abdominal mass or intestinal obstruction as the initial symptom were diagnosed and treated much earlier. In rectal cancer, women and non‐smokers were diagnosed and treated quickly. Factors correlated with early cancer stage were found in colon cancer, including bloody stool as the initial symptom (OR = 2.63, 95% CI 1.08–6.25, P = 0.034) and a history of appendectomy (OR = 4.00, 95% CI 1.15–14.29, P = 0.029).

Conclusions

The factors contributing to early cancer detection were identified but their clinical value is limited. Diagnosis by symptoms suggesting CRC needs to be improved and CRC screening should be vigorously promoted.
Four new species of Adenocalymma (Bignoniaceae) and a key to the species from southeastern Brazil
Authors: Udulutsch Renata Giassi , Assis Marco Antonio de , Dias Pedro
Published: July 2012

Four new species of Adenocalymma (Bignoniaceae, Bignonieae) from southeastern Brazil are described and illustrated: A. aurantiacum, characterized by dark orange and infundibuliform corolla; A. cinereum, characterized by shrubby habit, greyish inflorescence, infundibuliform corolla, and exserted stamens; A. gibbosum, characterized by gibbous and orange corolla and an inflorescence with dendritic trichomes; and A. sessile, characterized by sessile leaves and gibbous corolla. A discussion on the relationships of the new taxa and a key to all 29 species of Adenocalymma reported from southeastern Brazil are provided.
VOLE POPULATION DYNAMICS UNDER THE INFLUENCE OF SPECIALIST AND GENERALIST PREDATION
Authors: MUKHOPADHYAY B. , BHATTACHARYYA R.
Published: July 2012

Abstract To understand the impact of predation by different types of predators on the vole population dynamics, we formulate a three differential equation model describing the population dynamics of voles, the “specialist predator” and the “generalist predator.” First we perform a local stability study of the different steady states of the basic model and deduce that the predation rates of the “specialist” as well as the “generalist” predator are the main parameters controlling the existence/extinction criteria of the concerned populations. Next we analyze the model from a thermodynamic perspective and study the thermodynamic stability of the different equilibria. Finally using stochastic driving forces, we incorporate the exogenous factor of environmental forcing and investigate the stochastic stability of the system. We compare the stability criteria of the different steady states under deterministic, thermodynamic and stochastic situations. The analysis reveals that when the “specialist” and the “generalist” predator are modeled separately, the system exhibits rich dynamics and the predation rates of both types of predators play a major role in controlling vole oscillation and/or stability. These findings are also seen to resemble closely with the observed behavior of voles in the natural setting. Numerical simulations are carried out to illustrate analytical findings.
Autologous point‐of‐care cellular therapies variably induce equine mesenchymal stem cell migration, proliferation and cytokine expression
Authors: KOL A. , WALKER N. J. , GALUPPO L. D. , CLARK K. C. , BUERCHLER S. , BERNANKE A. , BORJESSON D. L.
Published: July 2012

Reasons for performing study: Autologous cellular therapy products including adipose‐derived stromal vascular fraction (SVF), bone marrow mononuclear cells (BMMNs), cord blood mononuclear cells (CBMNs) and platelet rich plasma are options for treatment of acute orthopaedic lesions while mesenchymal stem cells (MSCs) are culture expanded. These products may contribute to healing by secreting matrix proteins or growth factors, but they may also act on endogenous MSCs to facilitate healing.

Objectives: To determine the effects of cell therapy products on MSCs function in vitro. The hypothesis was that cell therapy products promote MSCs functions including proliferation, migration and mediator release.

Methods: Fat, bone marrow (BM), cord blood and platelets were obtained from 6 Quarter Horses. The BM‐MSCs and their autologous cell therapy products were co‐incubated in transwells. Mesenchymal stem cells proliferation, migration, gene expression and cytokine concentrations were determined.

Results: All cell therapy products increased MSCs proliferation, but SVF induced significantly more proliferation than any other product. Also SVF elicited more MSCs chemotaxis and, along with BMMNs, significantly more MSCs chemoinvasion. Cord blood mononuclear cells stimulated MSCs to produce high concentrations of interleukin‐6 (IL‐6), transforming growth factor‐β1 (TGF‐β1), and prostaglandin E2 (PGE2). Stromal vascular fraction and platelet lysate did not stimulate MSCs but SVF and platelet lysate themselves contained high concentrations of PGE2 and IL‐6 (SVF) and TGF‐β1 (platelet lysate).

Conclusions: Autologous cell products variably stimulate MSCs functions with 2 primary patterns apparent. Products either contained preformed mediators that may have intrinsic healing function, or products stimulated MSCs to secrete mediators.

Potential relevance: The specific clinical indications for these products may differ to include administration as a sole treatment modality prior to MSCs injection for intrinsic cell and cytokine activity (i.e. SVF) or administration concurrently with MSCs to activate MSCs for treatment of chronic lesions (i.e. CBMNs).
Generic Torelli theorem for Prym varieties of ramified coverings
Authors: Marcucci Valeria Ornella , Pirola Gian Pietro
Published: July 2012

We consider the Prym map from the space of double coverings of a curve of genus gwithrbranch points to the moduli space of abelian varieties. We prove that 𝒫:ℛg,r→𝒜δg−1+r/2is generically injective ifWe also show that a very general Prym variety of dimension at least 4 is not isogenous to a Jacobian.
Enhancement of temporal cues to pitch in cochlear implants: Effects on pitch ranking
Authors: Vandali Andrew E. , van Hoesel Richard J. M.
Published: July 2012

The abilities to hear changes in pitch for sung vowels and understand speech using an experimental sound coding strategy (eTone) that enhanced coding of temporal fundamental frequency (F0) information were tested in six cochlear implant users, and compared with performance using their clinical (ACE) strategy. In addition, rate- and modulation rate-pitch difference limens (DLs) were measured using synthetic stimuli with F0s below 300 Hz to determine psychophysical abilities of each subject and to provide experience in attending to rate cues for the judgment of pitch. Sung-vowel pitch ranking tests for stimuli separated by three semitones presented across an F0 range of one octave (139–277 Hz) showed a significant benefit for the experimental strategy compared to ACE. Average d-prime (d′) values for eTone (d′ = 1.05) were approximately three time larger than for ACE (d′ = 0.35). Similar scores for both strategies in the speech recognition tests showed that coding of segmental speech information by the experimental strategy was not degraded. Average F0 DLs were consistent with results from previous studies and for all subjects were less than or equal to approximately three semitones for F0s of 125 and 200 Hz.
Spatial cues alone produce inaccurate sound segregation: The effect of interaural time differences
Authors: Schwartz Andrew , McDermott Josh H. , Shinn-Cunningham Barbara
Published: July 2012

To clarify the role of spatial cues in sound segregation, this study explored whether interaural time differences (ITDs) are sufficient to allow listeners to identify a novel sound source from a mixture of sources. Listeners heard mixtures of two synthetic sounds, a target and distractor, each of which possessed naturalistic spectrotemporal correlations but otherwise lacked strong grouping cues, and which contained either the same or different ITDs. When the task was to judge whether a probe sound matched a source in the preceding mixture, performance improved greatly when the same target was presented repeatedly across distinct distractors, consistent with previous results. In contrast, performance improved only slightly with ITD separation of target and distractor, even when spectrotemporal overlap between target and distractor was reduced. However, when subjects localized, rather than identified, the sources in the mixture, sources with different ITDs were reported as two sources at distinct and accurately identified locations. ITDs alone thus enable listeners to perceptually segregate mixtures of sources, but the perceived content of these sources is inaccurate when other segregation cues, such as harmonicity and common onsets and offsets, do not also promote proper source separation.
Spatial release from masking in children with normal hearing and with bilateral cochlear implants: Effect of interferer asymmetry
Authors: Misurelli Sara M. , Litovsky Ruth Y.
Published: July 2012

Spatial release from masking (SRM) was measured in groups of children with bilateral cochlear implants (BiCIs, average ages 6.0 and 7.9 yr) and with normal hearing (NH, average ages 5.0 and 7.8 yr). Speech reception thresholds (SRTs) were measured for target speech in front (0°), and interferers in front, distributed asymmetrically toward the right (+90°/+90°) or distributed symmetrically toward the right and left (+90°/−90°). In the asymmetrical condition both monaural “better ear” and binaural cues are available. In the symmetrical condition, listeners rely heavily on binaural cues to segregate sources. SRM was computed as the difference between SRTs in the front condition and SRTs in either the asymmetrical or symmetrical conditions. Results showed that asymmetrical SRM was smaller in BiCI users than NH children. Furthermore, NH children showed symmetrical SRM, suggesting they are able to use binaural cues for source segregation, whereas children with BiCIs had minimal or absent symmetrical SRM. These findings suggest that children who receive BiCIs can segregate speech from noise under conditions that maximize monaural better ear cues. Limitations in the CI devices likely play an important role in limiting SRM. Thus, improvement in spatial hearing abilities in children with BiCIs may require binaural processing strategies.
Theoretical investigations of energy harvesting efficiency from structural vibrations using piezoelectric and electromagnetic oscillators
Authors: Harne Ryan L.
Published: July 2012

Conversion of ambient vibrational energy into electric power has been the impetus of much modern research. The traditional analysis has focused on absolute electrical power output from the harvesting devices and efficiency defined as the convertibility of an infinite resource of vibration excitation into power. This perspective has limited extensibility when applying resonant harvesters to host resonant structures when the inertial influence of the harvester is more significant. Instead, this work pursues a fundamental understanding of the coupled dynamics of a main mass-spring-damper system to which an electromagnetic or piezoelectric mass-spring-damper is attached. The governing equations are derived, a metric of efficiency is presented, and analysis is undertaken. It is found that electromagnetic energy harvesting efficiency and maximum power output is limited by the strength of the coupling such that no split system resonances are induced for a given mass ratio. For piezoelectric harvesters, only the coupling strength and certain design requirements dictate maximum power and efficiency achievable. Since the harvesting circuitry must “follow” the split resonances as the piezoelectric harvesters become more massive, the optimum design of piezoelectric harvesters appears to be more involved than for electromagnetic devices.
A study of jaw coarticulatory resistance and aggressiveness for Catalan consonants and vowels
Authors: Recasens Daniel
Published: July 2012

The goal of this study is to investigate coarticulatory resistance and aggressiveness for the jaw in Catalan consonants and vowels and, more specifically, for the alveolopalatal nasal /ɲ/ and for dark /l/ for which there is little or no data on jaw position and coarticulation. Jaw movement data for symmetrical vowel-consonant-vowel sequences with the consonants /p, n, l, s, ∫, ɲ, k/ and the vowels /i, a, u/ were recorded by three Catalan speakers with a midsagittal magnetometer. Data reveal that jaw height is greater for /s, ∫/ than for /p, ɲ/, which is greater than for /n, l, k/ during the consonant, and for /i, u/ than for /a/ during the vowel. Differences in coarticulatory variability among consonants and vowels are inversely related to differences in jaw height, i.e., fricatives and high vowels are most resistant, and /n, l, k/ and the low vowel are least resistant. Moreover, coarticulation resistant phonetic segments exert more prominent effects and, thus, are more aggressive than segments specified for a lower degree of coarticulatory resistance. Data are discussed in the light of the degree of articulatory constraint model of coarticulation.
Time-domain noise reduction based on an orthogonal decomposition for desired signal extraction
Authors: Benesty Jacob , Chen Jingdong , (Arden) Huang Yiteng , Gaensler Tomas
Published: July 2012

This paper addresses the problem of noise reduction in the time domain where the clean speech sample at every time instant is estimated by filtering a vector of the noisy speech signal. Such a clean speech estimate consists of both the filtered speech and residual noise (filtered noise) as the noisy vector is the sum of the clean speech and noise vectors. Traditionally, the filtered speech is treated as the desired signal after noise reduction. This paper proposes to decompose the clean speech vector into two orthogonal components: one is correlated and the other is uncorrelated with the current clean speech sample. While the correlated component helps estimate the clean speech, it is shown that the uncorrelated component interferes with the estimation, just as the additive noise. Based on this orthogonal decomposition, the paper presents a way to define the error signal and cost functions and addresses the issue of how to design different optimal noise reduction filters by optimizing these cost functions. Specifically, it discusses how to design the maximum SNR filter, the Wiener filter, the minimum variance distortionless response (MVDR) filter, the tradeoff filter, and the linearly constrained minimum variance (LCMV) filter. It demonstrates that the maximum SNR, Wiener, MVDR, and tradeoff filters are identical up to a scaling factor. It also shows from the orthogonal decomposition that many performance measures can be defined, which seem to be more appropriate than the traditional ones for the evaluation of the noise reduction filters.
Comodulation masking release: Effects of training and experimental design on use of within- and across-channel cues
Authors: Goldman Simon A. , Baer Thomas , Moore Brian C. J.
Published: July 2012

The effects of training and experimental design on comodulation masking release (CMR) were assessed. The study of Dau et al. [(2009), J. Acoust. Soc. Am. 125, 2182–2188], which used auditory-grouping manipulations to distinguish the use of within- and across-channel cues to CMR, was replicated in Experiment One but using naive subjects and an experimental design that minimized familiarization with the cues. Subjects made effective use of within- but not across-channel cues. Experiment Two examined training effects over more testing sessions, across four experimental designs (to minimize or maximize repeated exposure to the cues) and using an auditory grouping manipulation (“postcursors”) to distinguish the use of within- and across-channel cues. Naive subjects were tested with either two or four flanking bands (FBs), to determine if training effects varied with the amount of FB information. Within-channel cues could be used from the outset, but effective use of across-channel cues required training when they were less salient. Increased repeated exposure enhanced the effects of training. Experiment Three tested naive subjects using two FBs, but with noise presented continuously and a different auditory grouping manipulation, after Grose et al. [(2009), J. Acoust. Soc. Am. 125, 282–293]. CMR was large from the outset.
A relation between multipath group velocity, mode number, and ray cycle distance
Authors: Harrison Chris H.
Published: July 2012

Weston’s ray invariant or “characteristic time” in a range-dependent environment is exactly equivalent to the Wentzel–Kramers–Brillouin phase integral for ducted normal modes. By considering a ray element it is shown that the ray invariant can also be written in terms of ray cycle distance and cycle time. This leads to a useful formula for group velocity in terms of cycle distance and mode number. Drawing a distinction between the ray and wave interpretation, the Airy phase (i.e., the existence of a group velocity minimum) can be included in this approach. Favorable comparisons are made with group velocities derived from a normal mode model. The relationship is valid for variable sound speed and variable bathymetry, and this is demonstrated numerically. The formula is applicable to active sonar, multipath pulse shape, target signatures, reverberation, tomography, and underwater communications.
Pitch perception of concurrent harmonic tones with overlapping spectra
Authors: Wang Jian , Baer Thomas , Glasberg Brian R. , Stone Michael A. , Ye Datian , Moore Brian C. J.
Published: July 2012

Fundamental frequency difference limens (F0DLs) were measured for a target harmonic complex tone with nominal fundamental frequency (F0) of 200 Hz, in the presence and absence of a harmonic masker with overlapping spectrum. The F0 of the masker was 0, ±3, or ±6 semitones relative to 200 Hz. The stimuli were bandpass filtered into three regions: 0–1000 Hz (low, L), 1600–2400 Hz (medium, M), and 2800–3600 Hz (high, H), and a background noise was used to mask combination tones and to limit the audibility of components falling on the filter skirts. The components of the target or masker started either in cosine or random phase. Generally, the effect of F0 difference between target and masker was small. For the target alone, F0DLs were larger for random than cosine phase for region H. For the target plus masker, F0DLs were larger when the target had random phase than cosine phase for regions M and H. F0DLs increased with increasing center frequency of the bandpass filter. Modeling using excitation patterns and “summary autocorrelation” and “stabilized auditory image” models suggested that use of temporal fine structure information can account for the small F0DLs obtained when harmonics are barely, if at all, resolved.
Effect of source–tract acoustical coupling on the oscillation onset of the vocal folds
Authors: Lucero Jorge C. , Lourenço Kélem G. , Hermant Nicolas , Van Hirtum Annemie , Pelorson Xavier
Published: July 2012

This paper analyzes the interaction between the vocal folds and vocal tract at phonation onset due to the acoustical coupling between both systems. Data collected from a mechanical replica of the vocal folds show that changes in vocal tract length induce fluctuations in the oscillation threshold values of both subglottal pressure and frequency. Frequency jumps and maxima of the threshold pressure occur when the oscillation frequency is slightly above a vocal tract resonance. Both the downstream and upstream vocal tracts may produce those same effects. A simple mathematical model is next proposed, based on a lumped description of tissue mechanics, quasi-steady flow and one-dimensional acoustics. The model shows that the frequency jumps are produced by saddle-node bifurcations between limit cycles forming a classical pattern of a cusp catastrophe. The transition from a low frequency oscillation to a high frequency one may be achieved through two different paths: in case of a large acoustical coupling (narrow vocal tract) or high subglottal pressure, the bifurcations are crossed, which causes a frequency jump with a hysteresis loop. By reducing the acoustical coupling (wide vocal tract) or the subglottal pressure, a path around the bifurcations may be followed with a smooth frequency variation.
An application of the Peano series expansion to predict sound propagation in materials with continuous pore stratification
Authors: Geslain A. , Groby J. P. , Dazel O. , Mahasaranon S. , Horoshenkov K. V. , Khan A.
Published: July 2012

This work reports on an application of the state vector (Stroh) formalism and Peano series expansion to solve the problem of sound propagation in a material with continuous pore stratification. An alternative Biot formulation is used to link the equivalent velocity in the oscillatory flow in the material pores with the acoustic pressure gradient. In this formulation, the complex dynamic density and bulk modulus are predicted using the equivalent fluid flow model developed by Horoshenkov and Swift [J. Acoust. Soc. Am. 110(5), 2371–2378 (2001)] under the rigid frame approximation. This model is validated against experimental data obtained for a 140 mm thick material specimen with continuous pore size stratification and relatively constant porosity. This material has been produced from polyurethane binder solution placed in a container with a vented top and sealed bottom to achieve a gradient in the reaction time which caused a pore size stratification to develop as a function of depth [Mahasaranon et al., J. Appl. Phys. 111, 084901 (2012)]. It is shown that the acoustical properties of this class of materials can be accurately predicted with the adopted theoretical model.
Apparent auditory source width insensitivity in older hearing-impaired individuals
Authors: Whitmer William M. , Seeber Bernhard U. , Akeroyd Michael A.
Published: July 2012

Previous studies have shown a loss in the precision of horizontal localization responses of older hearing-impaired (HI) individuals, along with potentially poorer neural representations of sound-source location. These deficits could be the result or corollary of greater difficulties in discriminating spatial images, and the insensitivity to punctate sound sources. This hypothesis was tested in three headphone-presentation experiments varying interaural coherence (IC), the cue most associated with apparent auditory source width. First, thresholds for differences in IC were measured for a broad sampling of participants. Older HI participants were significantly worse at discriminating IC across reference values than younger normal-hearing participants. These results are consistent with senescent increases in temporal jitter. Performance decreased with age, a finding corroborated in a second discrimination experiment using a separate group of participants matched for hearing loss. This group also completed a third, visual experiment, with both a cross-mapping task where they drew the size of the sound they heard and the identification task where they chose the image that best corresponded to what they heard. The results from the visual tasks indicate that older HI individuals do not hear punctate images and are relatively insensitive to changes in width based on IC.
Speakers’ comfort and voice level variation in classrooms: Laboratory research
Authors: Pelegrín-García David , Brunskog Jonas
Published: July 2012

Teachers adjust their voice levels under different classroom acoustics conditions, even in the absence of background noise. Laboratory experiments have been conducted in order to understand further this relationship and to determine optimum room acoustic conditions for speaking. Under simulated acoustic environments, talkers do modify their voice levels linearly with the measure voice support, and the slope of this relationship is referred to as room effect. The magnitude of the room effect depends highly on the instruction used and on the individuals. Group-wise, the average room effect ranges from −0.93 dB/dB, with free speech, to −0.1 dB/dB with other less demanding communication tasks as reading and talking at short distances. The room effect for some individuals can be as strong as −1.7 dB/dB. A questionnaire investigation showed that the acoustic comfort for talking in classrooms, in the absence of background noise, is correlated to the decay times derived from an impulse response measured from the mouth to the ears of a talker, and that there is a maximum of preference for decay times between 0.4 and 0.5 s. Teachers with self-reported voice problems prefer higher decay times to speak in than their healthy colleagues.
Compressive matched-field processing
Authors: Mantzel William , Romberg Justin , Sabra Karim
Published: July 2012

Source localization by matched-field processing (MFP) generally involves solving a number of computationally intensive partial differential equations. This paper introduces a technique that mitigates this computational workload by “compressing” these computations. Drawing on key concepts from the recently developed field of compressed sensing, it shows how a low-dimensional proxy for the Green’s function can be constructed by backpropagating a small set of random receiver vectors. Then the source can be located by performing a number of “short” correlations between this proxy and the projection of the recorded acoustic data in the compressed space. Numerical experiments in a Pekeris ocean waveguide are presented that demonstrate that this compressed version of MFP is as effective as traditional MFP even when the compression is significant. The results are particularly promising in the broadband regime where using as few as two random backpropagations per frequency performs almost as well as the traditional broadband MFP but with the added benefit of generic applicability. That is, the computationally intensive backpropagations may be computed offline independently from the received signals, and may be reused to locate any source within the search grid area.
Passive imaging with pulsed ultrasound insonations
Authors: Haworth Kevin J. , Mast T. Douglas , Radhakrishnan Kirthi , Burgess Mark T. , Kopechek Jonathan A. , Huang Shao-Ling , McPherson David D. , Holland Christy K.
Published: July 2012

Previously, passive cavitation imaging has been described in the context of continuous-wave high-intensity focused ultrasound thermal ablation. However, the technique has potential use as a feedback mechanism for pulsed-wave therapies, such as ultrasound-mediated drug delivery. In this paper, results of experiments and simulations are reported to demonstrate the feasibility of passive cavitation imaging using pulsed ultrasound insonations and how the images depend on pulsed ultrasound parameters. The passive cavitation images were formed from channel data that was beamformed in the frequency domain. Experiments were performed in an invitro flow phantom with an experimental echo contrast agent, echogenic liposomes, as cavitation nuclei. It was found that the pulse duration and envelope have minimal impact on the image resolution achieved. The passive cavitation image amplitude scales linearly with the cavitation emission energy. Cavitation images for both stable and inertial cavitation can be obtained from the same received data set.
High-Resolution Definition of Vaccine-Elicited B Cell Responses Against the HIV Primary Receptor Binding Site
Authors: Sundling Christopher , Li Yuxing , Huynh Nick , Poulsen Christian , Wilson Richard , O’Dell Sijy , Feng Yu , Mascola John R. , Wyatt Richard T. , Karlsson Hedestam Gunilla B.
Published: July 2012

Vaccine-elicited mAbs bind the HIV-1 Env CD4bs differently from broadly neutralizing infection-induced mAbs.
PGC-1α Rescues Huntington’s Disease Proteotoxicity by Preventing Oxidative Stress and Promoting TFEB Function
Authors: Tsunemi Taiji , Ashe Travis D. , Morrison Bradley E. , Soriano Kathryn R. , Au Jonathan , Roque Ruben A. Vázquez , Lazarowski Eduardo R. , Damian Vincent A. , Masliah Eliezer , La Spada Albert R.
Published: July 2012

PGC-1α rescues Huntington’s disease neurodegeneration by reducing reactive oxygen species and inducing a master regulator of autophagy.
Matrix Metalloproteinase Induction of Rac1b, a Key Effector of Lung Cancer Progression
Authors: Stallings-Mann Melody L. , Waldmann Jens , Zhang Ying , Miller Erin , Gauthier Mona L. , Visscher Daniel W. , Downey Gregory P. , Radisky Evette S. , Fields Alan P. , Radisky Derek C.
Published: July 2012

Rac1b mediates the matrix metalloproteinase–induced epithelial-mesenchymal transition in lung adenocarcinoma and is a potential therapeutic target in early-stage lung cancer.
How important it is to determine the blood pressure in paediatric patients?
Authors: Pinto Pais Isabel , Novo Ana , Figueiredo Margarida , Mota Conceicao
Published: July 2012

The prevalence of hypertension among the paediatric population is 1%–2%. The emergency physician should recognise potentially harmful blood pressure (BP) levels and ensure they are adequately treated, in order to avoid life-threatening complications. A hypertensive emergency is a severely elevated BP complicated by target organ dysfunction (cardiovascular, cerebrovascular and/or renal). Hypertensive urgency, however, is a severe elevation in BP without target organ dysfunction. This distinction is critical for the clinical approach. The authors present a case of a severe hypertension due to primary focal segmental glomerulosclerosis. In this case, the lack of BP measurement in the infant surveillance and the devaluation of an albuminuria detected in a previous routine urine examination, have culminated in a late diagnosis of a severe hypertension, with subsequent effects on target organs.
A multidisciplinary intervention to facilitate return to work in cancer patients: intervention protocol and design of a feasibility study
Authors: Groeneveld Iris F , de Boer Angela G E M , Frings-Dresen Monique H W
Published: July 2012

Introduction

Returning to work can be problematic for cancer survivors due to suboptimal workplace support, a heavy workload, decreased physical functioning and fatigue. The timely and permanent return to work (RtW) of cancer patients favourably influences quality of life and economic independence. Multidisciplinary interventions aimed at timely and enduring RtW are lacking. The objectives of this article are (1) to describe the protocol of an intervention aimed at RtW of cancer patients, comprising of counselling by an oncological occupational physician and supervised physical exercise in a clinical setting during treatment and (2) to present the design of the study aimed at evaluating the feasibility of this intervention.

Methods and analysis

The intervention comprises three counselling sessions with an oncological occupational physician and a 12-week moderate-to-high intensity physical exercise programme, starting at the onset of chemotherapy. The intervention is aimed at cancer patients treated with curative intent, aged 18–60 years, employed and on sick leave. It will take place in two large medical centres in the Netherlands. The feasibility of the intervention will be evaluated as follows: the number of sessions, topics discussed and exercises executed will be registered by care providers; patients' and care providers' opinions will be assessed by questionnaires and interviews, respectively; and the proportion of invited patients that participated will be calculated.

Ethics and dissemination

The study results will be used for optimising the intervention content and may serve as a foundation for future implementation. The Medical Ethics Committees of the Academic Medical Center and the participating medical centres approved the study protocol.
A comparison of the accuracy of clinical decisions based on full-text articles and on journal abstracts alone: a study among residents in a tertiary care hospital
Authors: Marcelo Alvin , Gavino Alex , Isip-Tan Iris Thiele , Apostol-Nicodemus Leilanie , Mesa-Gaerlan Faith Joan , Firaza Paul Nimrod , Faustorilla John Francis , Callaghan Fiona M , Fontelo Paul
Published: July 2012

Background

Many clinicians depend solely on journal abstracts to guide clinical decisions.

Objectives

This study aims to determine if there are differences in the accuracy of responses to simulated cases between resident physicians provided with an abstract only and those with full-text articles. It also attempts to describe their information-seeking behaviour.

Methods

Seventy-seven resident physicians from four specialty departments of a tertiary care hospital completed a paper-based questionnaire with clinical simulation cases, then randomly assigned to two intervention groups—access to abstracts-only and access to both abstracts and full-text. While having access to medical literature, they completed an online version of the same questionnaire.

Findings

The average improvement across departments was not significantly different between the abstracts-only group and the full-text group (p=0.44), but when accounting for an interaction between intervention and department, the effect was significant (p=0.049) with improvement greater with full-text in the surgery department. Overall, the accuracy of responses was greater after the provision of either abstracts-only or full-text (p<0.0001). Although some residents indicated that ‘accumulated knowledge’ was sufficient to respond to the patient management questions, in most instances (83% of cases) they still sought medical literature.

Conclusions

Our findings support studies that doctors will use evidence when convenient and current evidence improved clinical decisions. The accuracy of decisions improved after the provision of evidence. Clinical decisions guided by full-text articles were more accurate than those guided by abstracts alone, but the results seem to be driven by a significant difference in one department.
The role of angiotensin receptor blockers in the prevention of cardiovascular and renal disease: time for reassessment?
Authors: Fuchs Flávio Danni
Published: July 2012

Angiotensin receptor blockers (ARB) have been recommended as a first option for the management of hypertension by guidelines, particularly in patients at high cardiovascular risk. The preference for ARB in these conditions is based on their neutral metabolic effects, and on direct cardiac and renal protective effects independent of the blood pressure-lowering effect (pleiotropic effects). Nonetheless, six large clinical trials designed to demonstrate such effects in patients at high cardiovascular risk, comparing ARB with placebo, failed to demonstrate any cardiovascular protection by ARB. In two trials there was higher cardiovascular mortality in patients treated with ARB. Their putative beneficial effect in the prevention of atrial fibrillation was not confirmed in four major clinical trials specifically designed to investigate this effect. Moreover, in various recent trials, treatment with ARB led to worse renal outcomes, such as an increased incidence of microalbuminuria, renal impairment and decreased glomerular filtration rate. The role of ARB for the prevention of cardiovascular and renal disease should be re-examined.