bluuebunny/crossref_metadata_2025 huggingface dataset:
Advancing clinical group verification framework for screening child speech sound disorders using “text-independent” i-Vectors
Authors: Kothalkar Prasanna V. , Rudolph Johanna M. , Dollaghan Christine , McGlothlin Jennifer , Campbell Thomas F. , Hansen John H. L.
Published: October 2018

I-Vectors are the current state-of-the-art feature representation in acoustic event identification tasks such as speaker recognition, language recognition, etc. They are referred to as identity vectors since they represent a unique quality of the speaker and have been useful for detecting adult speech pathologies . Speech Sound Disorders (SSDs) affect between 3% and 16% of US children and are difficult to detect due to the presence of developmental speech sound errors. We have been working to automate the process of speech screening. Our dataset consists of 29, single word recordings from 165, 3–6 year old children and was collected using an iOS application. Children were assigned to clinical groups using a percentage consonants correct growth curve model. Sixty-four children were classified as exhibiting an SSD, the rest as exhibiting normal speech acquisition. To achieve our purpose, we first introduced our clinical group verification framework using Gaussian Mixture Models. We extended the framework to screen the children’s speech based on single words using “text-dependent” i-Vectors, along with L2-logistic regression and Gaussian backend machine learning classifiers. This improved the algorithms’ accuracy. In the current study, we modified our offline post-processing algorithms within the framework, which provided excellent results for “text-independent” i-Vectors. Apart from the algorithms, we also present detailed visual analysis of the classifier score transformation, during the post-processing phase.
Quantifying expressive word learning in the presence of background speech
Authors: Simeon Katherine M. , Schramm Katie , Gordon Katherine , Grieco-Calub Tina M.
Published: October 2018

Children acquire novel word-object pairs rapidly and with few exposures via fast-mapping (Carey & Bartlett, 1978). However, everyday environments contain background noise that interferes with children’s formation of phonological representations of words. Existing research has not consistently shown disruption of receptive word learning by background noise when implementing a closed-set, forced-choice paradigm. In contrast, Riley & McGregor (2012) found that background noise disrupted expressive word form representation. The present study extends this prior work by investigating the effects of background speech on expressive word learning in preschool-aged children. Three-to-four-year-old children performed a fast-mapping task in quiet and in the presence of two-talker speech presented at a + 2 dB signal-to-noise ratio. Children viewed short animations whereby novel objects were verbally labeled. Children were then tested on each novel label-object pair with a tiered expressive recall task (Gordon & McGregor, 2014). For each object, children were asked to verbally produce its novel label. If children were unable to name the object, they were prompted with the label-initial sound (e.g., cueing) or given a closed-set of potential labels from which to choose the correct one. This presentation will discuss how depth of expressive word learning can vary in quiet and noisy environments.
The acoustic consequences for sibilants produced by glossectomies compared to healthy controls
Authors: Shadle Christine H. , Stone Maureen , Chen Wei-Rong
Published: October 2018

Glossectomy surgery affects the ability to elevate the tongue tip (Grimm et al, JSLHR v.60, 3417–3425, 2017), which is known to affect production of /s/. Interestingly, /∫/ is less affected by glossectomy surgery. In this study, the acoustics of normal and aberrant /s/ and /∫/ were characterized using three parameters developed for normal adults and adolescents. Main spectral peak (FM) indicates place of constriction. Amplitude difference (AD) indicates degree of sibilance. LevelD indicates relative energy between high and mid-frequencies, reflecting source changes. Subjects were two patients and three healthy controls for whom acoustic, perceptual, and MRI data existed. The controls were matched by gender and vocal tract size to the patients. The corpus included three words and four VCV syllables where C was /s, ∫/. Results showed the male patient, whose /s/ tokens were perceived as /∫/, had low FM values for /s/. The female patient had more varied and less severe errors. She produced perceptually-distinct /s/ and /∫/ and showed normal means but larger variances for /s/ than /∫ʃ/ parameters. Overall, the acoustic parameters match both the perceptual and articulatory (MRI) results, and help to explain the detailed effects of glossectomy surgery on the post-surgery productions. [Work supported by NIH CA-133015.]
Explorations of in-situ source localization in the deep ocean using frequency difference matched field processing and matched autoproduct processing
Authors: Geroski David J. , Dowling David R.
Published: October 2018

Matched field processing (MFP) is a well-known technique for source localization in challenging environments. MFP involves correlating array-recorded fields with calculated replica fields developed from knowledge of the acoustic environment. Incomplete knowledge of the environment causes mismatch between measured and calculated fields, and this mismatch can cause MFP to fail at relevant ranges and frequencies in the deep ocean. Given that the severity of this mismatch increases with frequency, a proposed remedy to the mismatch problem is to analyze the frequency-difference autoproduct of the recorded field, rather than the field itself. The phase of the frequency-difference autoproduct is expected to mimic that of an out-of-band field at a selectable below-band frequency, thereby mitigating the severity of the mismatch at in-band frequencies. This autoproduct is then matched either to a replica field at the below-band frequency, or to an appropriate calculated autoproduct field. This presentation explores these methods, and higher-order corrections, to localize moored sources using data from the North Pacific Acoustic Library. Localization statistics are presented based on the closest moored source, 130 km from the receiving array with a signal bandwidth from 200 to 300 Hz. [Sponsored by ONR.]
Resolving range aliasing in Omega-K synthetic aperture beamforming
Authors: Marston Timothy
Published: October 2018

The Omega-K algorithm is a beamforming algorithm that exploits Stolt migration in the wavenumber domain to focus stripmap synthetic aperture data. Because of its efficiency and its inherently broad-band properties it has been a common solution for synthetic aperture beamforming problems, especially in situations where trajectory perturbations are small and computational resources are limited. The algorithm is commonly divided into two stages: a bulk compression stage leveraging a phase multiplication in the wavenumber domain (sometimes used in isolation for resonance and shadow enhancement), which focuses data at the scene center, and Stolt migration which brings the entire scene into focus. For systems with very broad beamwidth the bulk compression stage can lead to spatial aliasing for close range scatterers, causing a loss of spatial spectrum information and increased noise. The cause of this frequently overlooked aliasing problem, its manifestation in SAS images, and methods for its avoidance will be discussed and demonstrated using both simulations and ClutterEX17 sonar data.
Deconvolved conventional beamforming for a planar array and Cramer Rao bound
Authors: Zhu Yiting , Yang T. C. , Pan Xiang
Published: October 2018

It is well known that the beam power output of conventional (delay and sum) beamforming (CBF) can be expressed as the convolution of the source distribution and the response of the beamformer to the point source. Consequently, the original source distribution can be recovered by deconvolution, yielding not only improved direction of arrival (DOA) estimation in terms of a narrower beam width and suppressed side lobes but also higher array gain than CBF (the deconvolution gain) as demonstrated by Yang for a uniformly spaced line array (ULA) [T. C. Yang, 10.1109/ JOE. 2017. 2680818]. In addition, the method is insensitive to signal mismatch and snapshot deficient problems in comparison with other high resolution methods such as minimum variance distortionless response (MVDR). In this paper, we extend the Richardson-Lucy algorithm for deconvolution to a planar array where the signal can be coming in any direction. Simulation analysis as well as experimental data will be presented to study the beam width and array gain as a function of number of receivers, the frequency of the incoming signals including narrow and broad band signals, and the ability to reject interference. We also calculate the Cramer-Rao bound to compare with the experimental result.
Ship of opportunity noise inversions for geoacoustic parameters of a layered mud-sand seabed
Authors: Tollefsen Dag , Dosso Stan E. , Knobles David P.
Published: October 2018

This paper considers the use of broadband noise from ship sources of opportunity in statistical inference for geoacoustic parameters of a layered seabed via a trans-dimensional Bayesian matched-field approach, with applications to data collected with a bottom-moored horizontal array in the 2017 Seabed Characterization Experiment conducted on the New England Shelf. The approach samples probabilistically over possible model parameterizations (number of seabed layers) and provides uncertainty estimates of seabed model parameters (sediment geoacoustic profiles). Approaches to accounting for (unknown) ship source level directionality when combining data from varying ship aspects to the array are addressed. Sediment parameter estimates from the inversions are compared with direct measurements from sediment cores and other geophysical data collected in the experiment area.
Seabed roughness measurement using the multibeam-subbottom-profiler SBP120
Authors: Pinson Samuel , Barbier Benjamin , Holland Charles W. , Stéphan Yann
Published: October 2018

In a recent paper [Pinson et al., J. Acoust. Soc. Am. 143, 2622–2631], theoretical interface echo scintillation, time-of-arrival variance, and angle-of-arrival variance have been derived as a function of the roughness autocorrelation function. Those parameters have been obtained under the Kirchhoff and small-roughness approximation by including integration over the source and receiver arrays in the Helmholtz-Kirchhoff integral. In this communication, we present the first roughness inversion results of at-sea recorded data based on the seabed-specular-echo fluctuation analysis. The data were recorded with the multibeam-subbottom-profiler SBP120 during the CALIMERO 2004 experiment campaign in the Gulf of Lion. [Research supported by the ONR Ocean Acoustics Program.]
Geoacoustic inversion using cross correlation function of low-frequency ambient noise in the Shallow Water 2006 Experiment
Authors: Yarina Marina , Katsnelson Boris , Qin Jixing , Godin Oleg A. , Tan Tsu Wei
Published: October 2018

In this paper, results of measurements and analysis of the cross correlation function (CCF) of the ambient noise field in a low frequency band (10–200 Hz) are presented. Records of the noise were obtained by single hydrophones (SHRUs) in the Shallow Water 2006 (SW06) experiment on the New Jersey continental shelf during about a month. Five SHRUs were placed approximately along a straight line perpendicular to the coastal line, distances between adjacent hydrophones were 5–8 km, ocean depth was 80–100 m. Analysis of the experimental data was carried out by calculating time-frequency diagrams of CCFs for different pairs of SHRUs, with subsequent mode filtering on the basis of the warping transform. Theoretical calculations of mode parameters for comparison with the experiment were done using different waveguide models, including the geoacoustic models previously proposed for the area of SW06 by other authors based on active source data. [Work supported by BSF-NSF grant.]
Seasonal patterns in marine mammal vocalizations in the western Canadian Arctic
Authors: Halliday William D. , Insley Stephen J. , Mouy Xavier
Published: October 2018

The Arctic marine environment is changing rapidly through a combination of sea ice loss and increased anthropogenic activity. Given that these changes can affect marine animals in a variety of ways, understanding the spatial and temporal distributions of Arctic marine animals is imperative. Here, we use passive acoustic monitoring to examine the presence of marine mammals in the western Canadian Arctic, where we have had recorders deployed near the communities of Sachs Harbour and Ulukhaktok, Northwest Territories, Canada. At both sites, we documented bowhead and beluga whales during the ice-free season, bearded seals throughout the ice-covered season and during their mating season, and ringed seals throughout the year. The sites also had different patterns in marine mammal presence, where we found whales later into the year at Ulukhaktok than at Sachs Harbour, and ringed seals vocalized much more at Ulukhaktok than at Sachs Harbour. These patterns in vocal activity at both sites help to document the presence of each species in the western Canadian Arctic, and serve as a baseline for future monitoring in the region. Next steps in this project involve deploying at more sites throughout the region to more comprehensively monitor marine mammals in the region.
Song production by the eastern North Pacific right whale, Eubalaena japonica
Authors: Crance Jessica , Berchok Catherine L. , Wright Dana , Brewer Arial , Woodrich Daniel
Published: October 2018

This paper describes unique, stereotyped, gunshot songs produced by the eastern North Pacific right whale (NPRW, Eubalaena japonica). Four unique songs were documented over eight years (2009–2017) and five separate locations in the southeastern Bering Sea. Similar to songs reported for other species, each NPRW song consists of a hierarchical structure of 1-3 different repeating phrases comprised predominantly of gunshot calls (though other call types were occasionally present). Songs were detected every year from July through early January. All four song structures remained consistent over eight years. Two different songs often occurred simultaneously; the same song never occurred simultaneously at the same location. However, the detection of the same song on the same day and time at two locations 310 km apart indicates multiple animals can produce the same song. These songs were localized to individual male NPRWs using directional sonobuoys; it remains unknown if females also sing. We hypothesize that these songs may be a reproductive display similar to song in other mysticetes. Although singing has not been documented in congeneric right whale species, songs presented here fit the classification of song attributed to other cetacean species. Possible functions of these songs and their management implications will be discussed.
Differential hearing sensitivity in the adaptive background in a beluga whale
Authors: Popov Vladimir , Nechaev Dmitry , Supin Alexander , Sysueva Evgeniya
Published: October 2018

The ability of the auditory system to maintain high differential sensitivity in the adaptive background was investigated in a beluga whale (Delphinapterus leucas). Adaptive background was a train of tone pips following one another at a rate of 1 kHz. Each pip consisted of eight carrier cycles of 64 kHz. Every 128 ms, the train of pips was interrupted for 16 ms and replaced with a test signal (16-ms series of the same tone pips as in the adaptive background, but of another level). The level of the test signals varied from -15 to + 20 dB relative the level of adaptive background. Evoked potentials (the rate following response, RFR) produced by the test signals were recorded. Increasing of adaptive level led to RFR thresholds growth. The 10-dB rising of adaptive signals intensity level led to 7.8 dB rising of test signal threshold. The response amplitude dependence on the test stimulus level was almost independent of the level of the adaptive background. Thus, the beluga’s auditory system displayed high sensitivity to the change in acoustic signal level in the high-level background. [This study was supported by the Russian Foundation for Basic Research (Grant No. 18-04-00088).]
Observation of Biot compressional waves of the second kind in granular soils
Authors: Nakagawa Koichi , Soga Kenichi , Mitchell James K.
Published: October 2018

The compressional wave of the second kind predicted theoretically by Biot was observed in granular soils using triaxial testing system. This theory models both the individual and coupled behavior of soil skeleton and pore fluid using the properties of pore space and elastic constants of the solid, pore fluid and solid skeleton. The wave is characterized by its large damping and hence detection of the wave in the laboratory is difficult. This difficulty was overcome by adopting highly sensitive sensor, signal stacking and appropriate filtering. The propagation of the P- and S-waves in granular materials was measured under different confining pressures and in both dry and saturated conditions. The phase of the Biot wave was the opposite to that of the P- and S- waves in all observed. According to the theory, the Biot wave results from the out-of-phase movement of the soil skeleton and pore fluid. The measured Biot wave velocities agree well with the theoretical values computed using the properties and parameters which were obtained primarily from laboratory tests. The good agreement demonstrates that the theory is valid for granular soils.
MUD, the next generation in acoustic backscatter sediment measurements
Authors: Mudge Todd D. , Lintern Gwyn , Lemon David , Borg Keath
Published: October 2018

Detection and classification of sediments within rarely occurring turbidity flows is challenging, in part because of the acoustic absorption and scattering within the dense suspended sediments. A new calibrated acoustic backscatter echosounder, the Multifrequency Ultrasonic Device (MUD™), was deployed from 13 to 16, May 2018, at about 120 m water depth within Bute Inlet, Canada. The MUD prototype (1.2 MHz, 769 kHz and 200 kHz) was deployed in a tautline mooring which included a passive acoustic recorder, an ADCP, CT sensor and OBS sensor. The frequencies for the prototype were selected to allow for a compromise between good acoustic range and penetration into dense flows with the potential for particle size discrimination. Preliminary analysis of the data indicates the presence of three turbidity flows over a two-hour period with speeds of up to 2.5 m/s. As anticipated, the lower frequencies did better in penetrating through the dense turbidity flow. This suggests that it will be possible to use inversion of the acoustic backscatter to estimate sediment concentrations within the dense head of the turbidity flow. Multifrequency inversion techniques will be applied to the less dense portion of the flow to estimate particle size distributions.
Inversion of range-dependent ocean environmental parameters using radiation noises of an Autonomous Underwater Vehicle
Authors: Xu Wen , Zhang Ming , Xu Yuanxin
Published: October 2018

Moving platform is playing an increasingly important role in ocean observatories. We previously reported some field testing results of using the radiation noises of an Autonomous Underwater Vehicle (AUV) as the sound source to invert the range-independent SSP. To incorporate source motion effects, the forward model based on the waveguide Doppler and normal mode theory was applied to compute the replica field, and to resolve the adjacent Doppler shifted frequencies, an analytical solution of the forward model and its simplified version were obtained for arbitrary signal integration intervals with a monochromatic source. In this paper, we reformulate the matched-field inversion problem into a state-space model to track the range-dependent environmental parameters and moving source parameters along the AUV path with the constantly updated measurement equations. Performances of several sequential filters, including extended Kalman, unscented Kalman, and particle filters, are compared. Note that at each point of the track, the estimate is the average from the source to the receiver; by doing the inversion sequentially with AUV moving, one can get the parameter estimate at individual points (sections). This process is equivalent to iteration over space, while iteration over time is considered as a solution to an under-determined inverse problem.
Observations and Feynman path integral analysis of acoustic fluctuations from the 2010-2011 Philippine Sea experiment
Authors: Colosi John A. , Miller Chis , Worcester Peter F. , Dzieciuch Matthew A. , Chandrayadula Tarun K.
Published: October 2018

Six acoustic sources arranged in a pentagon with a central point transmitted broadband signals in the frequency range 200–300 Hz to a water column spanning vertical array in the Philippine Sea from Spring 2010 to Spring 2011. The propagation ranges were 128, 210, 224, 379, 396, and 449 km. Observations of phase and intensity variance as well as vertical coherence were obtained for several ray identified wavefronts. These observations are compared to Feynman path integral theory predictions utilizing Garrett-Munk internal wave spectral fits to in-situ measurements of temperature, salinity, and current. The observations and theory suggest that the three shortest ranges are in the unsaturated regime while the three longer ranges are in the partially saturated regime. Vertical coherence lengths are well predicted by theory. Implications for future experiments designed to observe internal wave spectra acoustically will be discussed.
Philippine Sea deep water acoustic observations : A new test for acoustic wave propagation through random media models
Authors: Chandrayadula Tarun K. , Colosi John A. , Worcester Peter F. , Dzieciuch Matthew
Published: October 2018

A primary goal of the Philippine Sea (2010–2011) experiment was to test the ability of models to predict stochastic acoustic fluctuations. The experiment had six different sources transmitting broadband pulses (200 Hz–300 Hz) to a water column spanning vertical line array. The transmission ranges varied from 130 km to 450 km, and took place across a 250 km x 250 km area. The observations are a new opportunity for two reasons. First, the source frequencies are twice that of the previous experiments that used less than 100 Hz. Second, the oceanography is more dynamic than previous sites in the North Pacific with energetic mesoscale and internal tide variability. This talk uses acoustic mode observations to analyze both broadband and narrowband statistics. Narrowband comparisons focus on mode energy estimates at different frequencies, and these results are compared with the Colosi-Morozov model. Broadband observations focus on mode pulse temporal spreads and these results are compared to predictions from a hybrid cross frequency transport theory approach.
The feasibility of a multipurpose acoustic network in Baffin Bay
Authors: Rehm Eric , Dushaw Brian D. , Freitag Lee E. , Heaney Kevin D. , Carr Scott , Dakin Thomas , Fissel David , Heard Garry J.
Published: October 2018

Operating autonomous underwater vehicles at high latitudes is a challenge because ice cover prevents the use of GPS or data communications. As a result, our scientific observations are biased towards late spring, summer, and early autumn when ships can navigate and autonomous platforms can safely surface. To address this problem, we studied the feasibility of a basin-scale multipurpose acoustic network called the “Baffin Bay Acoustic Navigation and Communication System” (BBANC). BBANC would deploy broadband low frequency sources and receivers, offering one-way communication, acoustic positioning, and acoustic thermometry services. Passive acoustic listening elements would support the study of marine mammal communication and ambient noise from ships, ocean-based resource exploitation, and ice dynamics, as well as gate acoustic source operation in the presence of marine mammals. We describe the challenges and design parameters for such a system, as well as define additional acoustic and remote sensing measurements required to complete a system design. Drawing from a large database of Baffin Bay hydrography, we present simulations of under-ice sound speed conditions, ice properties derived from satellite remote sensing and upward looking sonar data, and modelled acoustic propagation paths in an ice-covered Baffin Bay. We also assess the feasibility of non-coherent and coherent communication.
Void fraction inference in cavitating fuel injector flows
Authors: Watson Lucas K. , Do Huy K. , Grace Sheryl , Ryan Emily , Holt R. G.
Published: October 2018

It has been shown that hydrodynamic cavitation within fuel injectors plays a significant role in their performance, with the desirable effect of broadening the resultant fuel spray. Experiments are challenging owing to the relatively small geometries, high pressure, and high Reynold’s number (Re) associated with such flows. Previous studies have observed cavitation in optically transparent nozzles at slower flows. By utilizing acoustic and vibration measurement techniques cavitation activity may be measured in a steel fuel injector at more practical Re flows used in applications. We report here experimental measurements taken using a laser vibrometer and a commercial fuel injector. Previous studies have demonstrated a resonant frequency shift as a function of injection pressure. Among competing hypotheses, our working hypothesis is that this shift is the result of mass unloading of cantilever mode oscillations of the fuel injector. The dynamic void fraction caused by cavitation activity within the fuel injector can then be inferred from the measured frequency shift. We report measurements of mode shapes and frequencies for static and flowing fuel injectors as functions of the flow rate.
Study on inversion of medium velocity change distribution based on code interference
Authors: qi zhiguang , Hou Hong , Gao Nansha
Published: October 2018

We introduce a method that was proposed in recent years to monitoring micro geological change. The contents of this technology include the extraction of green function from background noise, the theory of code wave interference and the distribution of sensitive nuclei. We extract the green's function from the background noise and get time delay, and then establish the sensitive nuclear distribution according to the physical characteristics of the measured medium and get the medium velocity variation distribution finally. Now we have carried out the code wave interference experiment of Panjin oilfield .In the process of oil exploitation, the vibration wave velocity can be changed due to the change of medium, which can be monitored by the code wave interference. 10 seismographs are set in the range of 1km x 3km oilfield and continuous collection of data is not less than two months, and map of the speed of the oil field working face as a function of time is obtained through the background noise code wave interference method.
Assessing the accuracy of head related transfer functions in a virtual reality environment
Authors: Esce Joseph A. , King Eoin A.
Published: October 2018

While graphics and visual representations for Virtual Reality (VR) systems are very well developed, the manner in which audio signals and acoustic environments are recreated in a VR system is not. In the case of audio spatialization, the current approach makes use of a library of standard head related transfer functions (HRTFs), i.e., a user selects a generic HRTF from a library, with limited personal information. It is essentially a “best-guess” representation of that individual’s HRTF. This limits the accuracy of audio developments for virtual reality. This paper reports on results from localization tests to determine the capabilities of a generic HRTF used in a VR environment. Volunteers entered a VR world, and an invisible sound source made a short bursts of white noise at various position in the room. Volunteers were asked to point to the location of the sound source, and results were captured to the nearest millimeter using the VR’s motion tracking system. It is proposed that future versions of this experimental methodology will enable the development of a pseudo-personalized HRTF, unique to each individual VR user.
Relationship of gender differences in preferences to economic development and gender equality
Authors: Falk Armin , Hermle Johannes
Published: October 2018

Assessing gender differences

What contributes to gender-associated differences in preferences such as the willingness to take risks, patience, altruism, positive and negative reciprocity, and trust? Falk and Hermle studied 80,000 individuals in 76 countries who participated in a Global Preference Survey and compared the data with country-level variables such as gross domestic product and indices of gender inequality. They observed that the more that women have equal opportunities, the more they differ from men in their preferences.

Science
, this issue p.
eaas9899
Supracellular contraction at the rear of neural crest cell groups drives collective chemotaxis
Authors: Shellard Adam , Szabó András , Trepat Xavier , Mayor Roberto
Published: October 2018

Supracellular cable drives collective cell movement

Neural crest cells migrate far and wide through a vertebrate embryo during development. Shellard
et al.
used
Xenopus
and zebrafish embryos to study how these clumps of mesenchymal cells migrate (see the Perspective by Adameyko). Movement was powered by a supracellular actomyosin cable that contracted around the rear of the clump. Similar supracellular contractility at the front was inhibited by a chemotactic signal. The imbalance in forces caused cells to rearrange so that the whole clump would be propelled forward.

Science
, this issue p.
339
; see also p.
290
Computational complexity, step by step
Authors: Montanaro Ashley
Published: October 2018

For certain linear algebra tasks, quantum circuits are proven to outperform classical ones
Magnetic hysteresis up to 80 kelvin in a dysprosium metallocene single-molecule magnet
Authors: Guo Fu-Sheng , Day Benjamin M. , Chen Yan-Cong , Tong Ming-Liang , Mansikkamäki Akseli , Layfield Richard A.
Published: October 2018

Breaking through the nitrogen ceiling

Single-molecule magnets could prove useful in miniaturizing a wide variety of devices. However, their application has been severely hindered by the need to cool them to extremely low temperature using liquid helium. Guo
et al.
now report a dysprosium compound that manifests magnetic hysteresis at temperatures up to 80 kelvin. The principles applied to tuning the ligands in this complex could point the way toward future architectures with even higher temperature performance.

Science
, this issue p.
1400
Resolved heart tamponade and controlled exophthalmos, facial pain and diabetes insipidus due to Erdheim-Chester disease
Authors: Monmany Jaume , Granell Esther , López Laura , Domingo Pere
Published: October 2018

A 69-year-old woman suffering from exophthalmos and facial pain came to us referred for aetiological diagnosis of exophthalmos. Orbital MRI showed thinned extrinsic ocular musculature, intraconal fat infiltration, retro-ocular compression and thickening of maxillary and sphenoid sinus walls. She had been suffering from diabetes insipidus for the last 7 years. During our diagnosis process, she presented signs of cardiac tamponade. Transthoracic heart ultrasound revealed large pericardial effusion and a heterogeneous mass that compressed the right ventricle. No osteosclerotic lesions on appendicular bones were present. Pericardiocentesis temporarily controlled tamponade and corticoid therapy temporarily abated exophthalmos. Pericardiectomy definitively resolved tamponade. Histological examination of pericardial tissue was conclusive of Erdheim-Chester disease. Exophthalmos responded to pegylated interferon-alpha-2a. Facial bone pain disappeared after zoledronic acid and interferon treatment. During interferon therapy, the patient suffered from a severe generalised desquamative exanthema that slowly resolved after discontinuing interferon. Diabetes insipidus remains controlled with desmopressin.
Verruciform xanthoma overlying inflammatory linear verrucous epidermal nevus and in broad segmental distribution
Authors: Singh Sanjay , Khandpur Sujay , Agarwal Shipra
Published: October 2018

A 17-year-old woman presented with moderately itchy, non-progressive, linearly arranged verrucous plaques over dorsum of left foot since early childhood. Two years ago, she developed slowly increasing, verrucous exophytic growth in posterior most aspect of linear verrucous plaque. One year ago, she also developed multiple, linearly arranged, fleshy plaques with surface crusting over lateral aspect of right leg extending to thigh. Biopsy from both verrucous lesion on left foot and fleshy plaque on right leg showed an exophytic growth with significant papillomatosis, neutrophils in stratum corneum, acanthosis and infiltration of papillary dermis with foamy macrophages that were CD 68 positive, features compatible with verruciform xanthoma (VX). Biopsy from linear verrucous plaque over left foot was consistent with inflammatory linear verrucous epidermal nevus (ILVEN). A diagnosis of segmental VX and VX overlying ILVEN was made.
Exercise for the prevention and treatment of low back, pelvic girdle and lumbopelvic pain during pregnancy: a systematic review and meta-analysis
Authors: Davenport Margie H , Marchand Andree-Anne , Mottola Michelle F , Poitras Veronica J , Gray Casey E , Jaramillo Garcia Alejandra , Barrowman Nick , Sobierajski Frances , James Marina , Meah Victoria L , Skow Rachel J , Riske Laurel , Nuspl Megan , Nagpal Taniya S , Courbalay Anne , Slater Linda G , Adamo Kristi B , Davies Gregory A , Barakat Ruben , Ruchat Stephanie-May
Published: October 2018

Objective

The purpose of this review was to investigate the relationship between prenatal exercise, and low back (LBP), pelvic girdle (PGP) and lumbopelvic (LBPP) pain.

Design

Systematic review with random effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were eligible (except case studies and reviews) if they were published in English, Spanish or French, and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise, alone [“exercise-only”] or in combination with other intervention components [eg, dietary; “exercise + co-intervention”]), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and outcome (prevalence and symptom severity of LBP, PGP and LBPP).

Results

The analyses included data from 32 studies (n=52 297 pregnant women). ‘Very low’ to ‘moderate’ quality evidence from 13 randomised controlled trials (RCTs) showed prenatal exercise did not reduce the odds of suffering from LBP, PGP and LBPP either in pregnancy or the postpartum period. However, ‘very low’ to ‘moderate’ quality evidence from 15 RCTs identified lower pain severity during pregnancy and the early postpartum period in women who exercised during pregnancy (standardised mean difference −1.03, 95% CI −1.58, –0.48) compared with those who did not exercise. These findings were supported by ‘very low’ quality evidence from other study designs.

Conclusion

Compared with not exercising, prenatal exercise decreased the severity of LBP, PGP or LBPP during and following pregnancy but did not decrease the odds of any of these conditions at any time point.
Impact of prenatal exercise on neonatal and childhood outcomes: a systematic review and meta-analysis
Authors: Davenport Margie H , Meah Victoria L , Ruchat Stephanie-May , Davies Gregory A , Skow Rachel J , Barrowman Nick , Adamo Kristi B , Poitras Veronica J , Gray Casey E , Jaramillo Garcia Alejandra , Sobierajski Frances , Riske Laurel , James Marina , Kathol Amariah J , Nuspl Megan , Marchand Andree-Anne , Nagpal Taniya S , Slater Linda G , Weeks Ashley , Barakat Ruben , Mottola Michelle F
Published: October 2018

Objective

We aimed to identify the relationship between maternal prenatal exercise and birth complications, and neonatal and childhood morphometric, metabolic and developmental outcomes.

Design

Systematic review with random-effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were eligible (except case studies and reviews) if published in English, Spanish or French, and contained information on the relevant population (pregnant women without contraindication to exercise), intervention (subjective/objective measures of frequency, intensity, duration, volume or type of exercise, alone (‘exercise-only’) or in combination with other intervention components (eg, dietary; ‘exercise+cointervention’)), comparator (no exercise or different frequency, intensity, duration, volume, type or trimester of exercise) and outcomes (preterm birth, gestational age at delivery, birth weight, low birth weight (<2500 g), high birth weight (>4000 g), small for gestational age, large for gestational age, intrauterine growth restriction, neonatal hypoglycaemia, metabolic acidosis (cord blood pH, base excess), hyperbilirubinaemia, Apgar scores, neonatal intensive care unit admittance, shoulder dystocia, brachial plexus injury, neonatal body composition (per cent body fat, body weight, body mass index (BMI), ponderal index), childhood obesity (per cent body fat, body weight, BMI) and developmental milestones (including cognitive, psychosocial, motor skills)).

Results

A total of 135 studies (n=166 094) were included. There was ‘high’ quality evidence from exercise-only randomised controlled trials (RCTs) showing a 39% reduction in the odds of having a baby >4000 g (macrosomia: 15 RCTs, n=3670; OR 0.61, 95% CI 0.41 to 0.92) in women who exercised compared with women who did not exercise, without affecting the odds of growth-restricted, preterm or low birth weight babies. Prenatal exercise was not associated with the other neonatal or infant outcomes that were examined.

Conclusions

Prenatal exercise is safe and beneficial for the fetus. Maternal exercise was associated with reduced odds of macrosomia (abnormally large babies) and was not associated with neonatal complications or adverse childhood outcomes.
Using internet search data to predict new HIV diagnoses in China: a modelling study
Authors: Zhang Qingpeng , Chai Yi , Li Xiaoming , Young Sean D , Zhou Jiaqi
Published: October 2018

Objectives

Internet data are important sources of abundant information regarding HIV epidemics and risk factors. A number of case studies found an association between internet searches and outbreaks of infectious diseases, including HIV. In this research, we examined the feasibility of using search query data to predict the number of new HIV diagnoses in China.

Design

We identified a set of search queries that are associated with new HIV diagnoses in China. We developed statistical models (negative binomial generalised linear model and its Bayesian variants) to estimate the number of new HIV diagnoses by using data of search queries (Baidu) and official statistics (for the entire country and for Guangdong province) for 7 years (2010 to 2016).

Results

Search query data were positively associated with the number of new HIV diagnoses in China and in Guangdong province. Experiments demonstrated that incorporating search query data could improve the prediction performance in nowcasting and forecasting tasks.

Conclusions

Baidu data can be used to predict the number of new HIV diagnoses in China up to the province level. This study demonstrates the feasibility of using search query data to predict new HIV diagnoses. Results could potentially facilitate timely evidence-based decision making and complement conventional programmes for HIV prevention.
Cohort study of workers at a New Zealand agrochemical plant to assess the effect of dioxin exposure on mortality
Authors: McBride David I , Collins James J , Bender Thomas John , Bodner Kenneth M , Aylward Lesa L
Published: October 2018

Objectives

To describe how the exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) influenced mortality in a cohort of workers who were exposed more recently, and at lower levels, than other cohorts of trichlorophenol process workers.

Design

A cohort study.

Setting

An agrochemical plant in New Zealand

Participants

1,599 men and women working between 1 January 1969 and 1 November 1988 at a plant producing the herbicide 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) with TCDD as a contaminant. Cumulative TCDD exposure was estimated for each individual in the study by a toxicokinetic model.

Primary outcome measures

Calculation of cause-specific standardised mortality ratios (SMRs) and 95% confidence intervals (95% CI’s) compared those never and ever exposed to TCDD. Dose–response trends were assessed firstly through SMRs stratified in quartiles of cumulative TCCD exposure, and secondly with a proportional hazards model.

Results

The model intercept of 5.1 ppt of TCDD was consistent with background TCDD concentrations in New Zealand among older members of the population. Exposed workers had non-significant increases in all-cancer deaths (SMR=1.08, 95% CI 0.86 to 1.34), non-Hodgkin lymphoma (SMR=1.57, 95% CI: 0.32 to 4.59), soft tissue sarcoma (one death) (SMR=2.38, 95% CI: 0.06 to 13.26), diabetes (SMR=1.27, 95% CI: 0.55 to 2.50) and ischaemic heart disease (SMR=1.21, 95% CI: 0.96 to 1.50). Lung cancer deaths (SMR=0.95, 95% CI: 0.56 to 1.53) were fewer than expected. Neither the stratified SMR nor the proportional hazard analysis showed a dose–response relationship.

Conclusion

There was no evidence of an increase in risk for ‘all cancers’, any specific cancer and no systematic trend in cancer risk with TCDD exposure. This argues against the carcinogenicity of TCDD at lower levels of exposure.
Parental attitudes and willingness to donate children’s biospecimens for congenital heart disease research: a cross-sectional study in Shanghai, China
Authors: Gao Hongxiang , Jiang Jun , Feng Bei , Guo Aihua , Hong Haifa , Liu Shijian
Published: October 2018

Objectives

To assess attitudes and willingness of parents of children with congenital heart disease (CHD) regarding donating biospecimens for future CHD research, and to identify factors associated with biospecimen donation.

Design

Face-to-face cross-sectional survey data were analysed using logistic regression.

Setting

Cardiothoracic Surgery Inpatient Department, Shanghai Children’s Medical Centre.

Participants

Parents of children attending the cardiothoracic surgery inpatient department at Shanghai Children’s Medical Center, 1 March–31 December 2016.

Primary and secondary outcome measures

Willingness and motivation regarding donating children’s biospecimens, and ethical and legal considerations concerning children’s future willingness to donate.

Results

Of 550 parents, 508 completed the questionnaire (response rate=92.4%). Overall, 69.1% (n=351) were willing to donate their children’s biospecimens for medical research. Multivariate analysis indicated higher education level (college/graduate degree: OR 2.435, 95% CI 1.221 to 4.857, p=0.012; high school: OR 1.827, 95% CI 1.190 to 2.804, p=0.006) and children’s hospitalisation history (OR 1.581; 95% CI 1.069 to 2.338, p=0.022) were positively associated with willingness to donate. The most common motivation for donation was potential benefit to other children with CHD (81.2%, n=285). The main barriers to donation were physical discomfort to their children (52.3%, n=54) and concerns about personal privacy (47.1%, n=48). Most parents (86.0%, n=302) wanted to be informed of research results using their children’s donated biospecimens, and 34.8% (n=177) believed that children aged 10–18 years had the right to consent independently to research participation.

Conclusions

Nearly 70% of the parents in this study were willing to donate their children’s biospecimens for future CHD research. Parents’ education level and children’s hospitalisation history influenced willingness to donate. Most parents wanted to receive the research results related to their children’s biospecimens.
Cross-sectional analysis of UK research studies in 2015: results from a scoping project with the UK Health Research Authority
Authors: Clark Tim , Wicentowski Richard H , Sydes Matthew R
Published: October 2018

Objectives

To determine whether data on research studies held by the UK Health Research Authority (HRA) could be summarised automatically with minimal manual intervention. There are numerous initiatives to reduce research waste by improving the design, conduct, analysis and reporting of clinical studies. However, quantitative data on the characteristics of clinical studies and the impact of the various initiatives are limited.

Design

Feasibility study, using 1 year of data.

Setting

We worked with the HRA on a pilot study using research applications submitted for UK-wide ethical review. We extracted into a single dataset, information held in anonymised XML files by the Integrated Research Application System (IRAS) and the HRA Assessment Review Portal (HARP). Research applications from 2014 to 2016 were provided. We used standard text extraction methods to assess information held in free-text fields. We use simple, descriptive methods to summarise the research activities that we extracted.

Participants

Not applicable—records-based study

Interventions

Not applicable.

Primary and secondary outcome measures

Feasibility of extraction and processing.

Results

We successfully imported 1775 non-duplicate research applications from the XML files into a single database. Of these, 963 were randomised controlled trials and 812 were other studies. Most studies received a favourable opinion. There was limited patient and public involvement in the studies. Most, but not all, studies were planned for publication of results. Novel study designs (eg, adaptive and Bayesian designs) were infrequently reported.

Conclusions

We have demonstrated that the data submitted from IRAS to the HRA and its HARP system are accessible and can be queried for information. We strongly encourage the development of fully resourced collaborative projects to further this work. This would aid understanding of how study characteristics change over time and across therapeutic areas, as well as the progress of initiatives to improve the quality and relevance of research studies.