bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of rocket launch data to propagation model results
Authors: Noble John
Published: May 2016

NASA’s Wallops Flight Facility launched medium lift rockets for experimental and space station resupply missions during 2013 and 2014. These launches have been a great opportunity to use the rocket-generated infrasound as a repeatable source to study long range propagation. Data from the US Array was used to compare the received amplitude from the rocket launches to a propagation model prediction using realistic atmospheric profiles for ranges out to 500 km from the launch point. The US Array was a distribution of infrasound and seismic sensors which range in a north/south strip across the United States and would periodically relocate further east over time. The results of this comparison will show how well the modeling was able to track the behavior in the measurements.
Restoring sensitivity to interaural timing differences in bilateral cochlear implant listeners using multi-electrode stimulation
Authors: Thakkar Tanvi D. , Kan Alan , Litovsky Ruth Y.
Published: May 2016

Identification and discrimination of sound sources in complex auditory environments is facilitated for normal-hearing listeners from access to interaural time differences (ITDs). For patients fitted with bilateral cochlear implants (BiCI), binaural sensitivity is harder to achieve due to several factors, including asynchronous interaural processing. BiCI listeners have shown good ITD sensitivity with low rates of electrical stimulation; however, low-rate delivery of ITD cues is unrealistic for the high-rate pulsatile stimulation required to achieve good speech understanding. One solution is to present a mix of high- and low-rate stimulation on different electrodes, preserving both speech recognition and sound localization ability. In the present study, a binaural benefit was observed in a mixed-rate strategy under direct electrical stimulation: ITD sensitivity was measured in a two-alternative forced-choice discrimination task, using seven multi-electrode conditions. We hypothesized that by introducing low-rate ITDs at a few electrodes alongside high-rate ITDs at remaining electrodes provides sufficient ITD cues for sound localization. The present data suggests the binaural system of BiCI listeners can extract pertinent cues to achieve ITD sensitivity even when high-rate ITD information is presented at the majority of the cochlear locations. This lends to a possibility in implementation of ITD cues to current processing strategies.
Shared monaural and binaural temporal processing limits in bilateral cochlear implant listeners
Authors: Ihlefeld Antje , Carlyon Robert P. , Kan Alan , Churchill Tyler H. , Litovsky Ruth Y.
Published: May 2016

Bilaterally implanted cochlear implant users were tested on monaural rate discrimination and binaural interaural time difference (ITD) discrimination, as a function of pulse rate, to examine the hypothesis that deterioration in performance at high rates occurs for the two tasks due to a common neural basis. For the rate discrimination task, pulse trains were presented to one electrode, located in the apical, middle, or basal part of the array, and in either the left or the right ear. In each two-interval trial, the standard stimulus had a rate of 100, 200, 300, or 500 pulses-per-second and the signal stimulus had a rate 35% higher. For the ITD discrimination task, performance between pitch-matched electrode pairs was measured for the same standard rates as in the rate discrimination task, and with an ITD of + /− 500 µs. Sensitivity (d′) on both tasks decreased with increasing rate. Results show that ITD scores for different pairs of electrodes correlated with the lower of the rate discrimination scores for those two electrodes. Statistical analysis, which partialed out overall differences between listeners, electrodes, and rates, supports the hypothesis that monaural and binaural temporal processing limitations are at least partly due to a common mechanism.
Sound-source enumeration by hearing-impaired adults
Authors: Akeroyd Michael A. , Whitmer William M. , McShefferty David , Naylor Graham
Published: May 2016

To help measure the veracity with which the auditory world is heard by hearing-impaired listeners, we studied the ability to count the number of discrete sources that are present. In two experiments, stimuli were newly selected 5-s samples of concatenated sentences from 1 to 7 locations in simulated rooms of varying reverberation, presented from a circular loudspeaker array. In the first experiment, listeners responded with the number of locations heard after each presentation. In the second experiment, listeners heard two presentations, an interval with n sources (one talker per location) and an interval with n + 1 sources; listeners responded which interval had more sources. Results corroborate recent work showing the maximum number of identifiable sources is roughly four. Asymmetry in hearing impairment reduced the ability to enumerate locations. Various conditions of presentation were tested: headphone and aided results were not markedly different from unaided results, and reverberation had only a modest inflating effect on the perceived number of sources. The ramifications for complex listening as well as the potential relation to cortical representations of auditory space are discussed. [Work supported by the MRC (U135097131) and the Chief Scientist Office (Scotland).]
Evaluating performance of hearing-impaired listeners with a visually-guided hearing aid in an audio-visual word congruence task
Authors: Roverud Elin , Best Virginia , Mason Christine R. , Streeter Timothy , Kidd Gerald
Published: May 2016

Hearing-impaired (HI) individuals typically experience greater difficulty listening selectively to a target talker in speech mixtures than do normal-hearing (NH) listeners. To assist HI listeners in these situations, the benefit of a visually guided hearing aid (VGHA)—highly directional amplification created by acoustic beamforming steered by eye gaze—is being evaluated. In past work with the VGHA, performance of NH listeners was assessed on an audio-visual word congruence task [e.g., Roverud et al., ARO 2015]. The present study extends this work to HI listeners. Three spoken words are presented simultaneously under headphones at each of three source locations separated in azimuth. A single word is printed on a monitor at an angle corresponding to one of the locations, indicating the auditory target word location. After each stimulus, listeners indicate whether the auditory target matches the printed word with a YES-NO response, ignoring the two masker words. Listeners visually track the printed word, which moves location trial-to-trial with a predetermined probability. Participants’ eye movements, measured by an eye tracker, steer the VGHA amplification beam. Performance is compared for the VGHA, stimuli processed with natural binaural information (KEMAR HRTFs), and a hybrid condition combining both types of information. [Work supported by NIDCD.]
Under-documented languages expand phonetic typology
Authors: Maddieson Ian
Published: May 2016

The set of speech sounds known to be used in human languages continues to grow ever larger as more information becomes available on previously under-documented languages. In addition, the range of contrastive distinctions known to be employed continues to be enlarged. A brief survey of categories of sounds that have been added to phonetic typology as a result of work on such languages will be presented, followed by exemplification of the specific case of Yélî Dnye (ISO 693 yle). This language, spoken on Rossel Island, Papua New Guinea by about 3000 people, has large contrastive inventories of both consonants and vowels (58 consonants, 34 vowels). It is the only language known to include sets of doubly articulated labial-alveolar and labial-postalveolar plosives and nasals in its inventory (in addition to the more widespread category of labial-velars). Moreover, the stops contrast plain, prenasalized and nasally released categories, and some of them occur distinctively palatalized. Thus, there are at least nine consonant types not known from any other language. Yélî Dnye is also the only language known to have a contrast between oral and nasalized vowels following nasally released stops. Our knowledge of this language therefore enlarges our perspective on how human languages may differ.
Consonant-tone interactions in Gengbe
Authors: Lotven Samson , Berkson Kelly
Published: May 2016

Gengbe is an under-documented and understudied Gbe language spoken as a lingua franca in Southern Togo and Benin. Few resources for Gengbe exist, especially in the domain of empirical acoustic phonetic research. To this end, we present an overview of its consonant, vowel, and tonal inventories. Of particular interest is the fact that its two register tones, (L)ow and (H)igh, show systematic phonological variation based on the voicing of onset consonants. Like many other tone languages in Africa and beyond, voiced obstruents act as so-called “depressor consonants,” triggering lower f0 on subsequent vowels than do their voiceless counterparts. This lowering is phonologized in many H tone contexts, resulting in a Rising tone in many (but not all) morphophonological environments. The distinction is phonetically present in low tone as well, where it perseverates across the entire vowel and results in a lower register L (by approx. 20 Hz). We survey the phonological environments where such lowering effects are realized, and probe the interaction between obstruent voicing, tone, vowel height, and nasality via instrumental acoustic analysis.
Voicing contrast in Ruwund
Authors: Demolin Didier
Published: May 2016

Ruwund has a set of voiceless and voiced stops in its phonemic inventory. Length measurements reveal that voiceless stops are realized with duration comparable to voiced stops. There is also a positive VOT varying between bilabial, alveolar, and velar places of articulation. Voiced stops are characterized by a negative VOT and have greater voicing intensity. What is striking in Ruwund is that voiceless stops are also produced with voicing of weak intensity. These sounds should therefore be described as voiced stops. The presence and amount of aspiration during the delay between the first burst and the onset of voicing is the cue that contributes to these sound’s identification as voiceless. Repp [1] observed that the increase in the amplitude of aspiration noise relative to the following periodic vocalic portion increases the salience of this cue and helps the probability to classify these consonants into the voiceless category. A perceptual test m confirms this hypothesis. Removing the part lying between the first burst and the following voiced part accounting for the beginning of the following vowel, show that listeners do not recognize these stops as voiceless anymore but as voiced. Ruwund reveal therefore new subtleties of voicing distinction and VOT. [1] B. Repp, “Relative amplitude of aspiration noise as a voicing cue for syllable-initial stop consonants,” Lang. Speech, 23, 173–189 (1979).
A computational classification of Thai lexical tones
Authors: Cooper-Leavitt Jamison E.
Published: May 2016

The leveling of contour tones in Thai, uttered in a continuous context, has served as a natural point of difficulty for tone recognition experiments. Two tone recognition experiments presented here both include five lexical Thai tones (high, mid, low, rising, and falling) as abstract Bayesian models incorporated into a multi-model Hidden Markov Model. The HMM was developed using Thai natural language utterances to test its performance in correctly identifying Thai lexical tone categories. All utterances used for testing and training were produced in a laboratory setting. Utterances for the first experiment were produced in a citation context, and utterances for the second experiment were produced in a continuous context. The results of the two experiments were compared to test if the context had a significant effect on correctly identifying tone category. Findings showed the context of the utterance had a significant effect on the HMM’s ability to correctly identify tone category, F(1,48) = 5.82, p = 0.020. The identification of the correct tone category for citation utterances showed a significant increase in performance than for the correct identification of tone category for continuous utterances, t(48) = 5.38, p < 0.001.
Weight-sensitive stress and acoustic correlates of disyllabic words in Marathi
Authors: Le Grezause Esther S.
Published: May 2016

Little of the literature on Marathi phonology addresses stress, and none of it systematically. The tentative accounts that do exist are contradictory in their descriptions (Pandharipande 1997, Dhongde and Wali 2009). Moreover, there is no research on the acoustic correlates of Marathi stress. To address this gap, this study investigates word-level stress and the acoustic correlates of stress in disyllabic words in Modern Standard Marathi. Since weight criteria vary across languages (Hayes 1995, Gordon 2004), the main goals are to determine what constitutes heavy syllables and whether or not long vowels behave like heavy vowels with two moras (µµ). Three main hypotheses are tested: (H1) stress is weight-sensitive, (H2) Marathi follows the Latin weight system (Gordon 2002) with CVX heavy, and (H3) when syllables have the same weight the left-most syllable bears stress. The study tests these hypotheses using auditory and spectrographic analyses of recordings from two native Marathi speakers. Results confirm all three hypotheses: H1: Marathi has weight-sensitive stress, H2: it follows the Latin weight distinction and, H3: the first syllable is stressed when syllable weight is equal. Preliminary acoustic results indicate that pitch, F1, and F2 are slightly higher in stressed syllables than in unstressed syllables.
Velopharyngeal status of vowels produced with and without hard glottal attack in children with repaired cleft palate
Authors: Eshghi Marziye , Zajac David J.
Published: May 2016

The objective of this study was to describe velopharyngeal (VP) closure patterns of isolated vowels produced by infants with repaired cleft palate (CP). Nasal ram pressure (NRP) and audio signals were obtained from six infants with repaired CP (four males and two females). Two infants were 12 months of age and four were 18 months of age. All infants were from American-English speaking families without known syndromes. A total number of 95 isolated vowels were analyzed perceptually and spectrographically. Fourteen vowels were identified as produced with hard glottal attack. Three infants produced all vowels with at least 96% complete VP closure. Three other infants produced all vowels with 59% complete VP closure and 39% partial VP closure. In addition, one of the infants produced an isolated vowel with a completely open velopharynx. Vowels with hard glottal attack, however, were produced with 100% complete VP closure across all subjects, regardless of VP status for vowels without hard glottal attack. It is hypothesized that early use of hard glottal attack by children with repaired CP might contribute to the often reported high prevalence of voice disorders and may even be associated with the development of glottal stop articulation. [Research reported in this publication was supported by the National Institute of Dental & Craniofacial Research of the National Institutes of Health under Award Number 1R01DE022566-01A1.]
Three-dimensional tongue shapes of /r/ production in American English words
Authors: Lulich Steven M. , Rhodes Brandon , Nelson Max , Berkson Kelly , de Jong Kenneth
Published: May 2016

A number of studies have shown that /r/ production in American English involves complex tongue shapes. Previous 3D imaging studies, however, have been limited to sustained (static) /r/ sounds produced in supine position. Since supine versus upright posture and static versus dynamic speech production influences the shape of the tongue, it is unclear to what degree previous findings of three-dimensional tongue shapes are generalizable to /r/ sounds produced dynamically and with upright posture. This study presents upright-posture 3D tongue shapes of dynamically produced /r/ sounds from words embedded in a carrier phrase. Twenty young adult native speakers of American English participated in the study (10 males and 10 females), and analyses are ongoing.
Articulatory targets for ultrasound biofeedback determined by tracking regional tongue displacements
Authors: Hamilton Sarah M. , Mast T. Douglas , Riley Michael , Boyce Suzanne
Published: May 2016

Ultrasound biofeedback therapy (UBT) is a significant alternative to traditional therapy for speech disorders, but some users make little progress with the standard feedback display. For segments such as American English /r/, the required tongue movements are so complex that an ultrasound image of the tongue cannot adequately guide speakers to make the right movements. We propose to develop visual display regimes for ultrasound biofeedback that maximize speaker learning. As a preliminary step, we determine displacement ranges of tongue regions (blade, root, and dorsum) known to characterize accurate /r/ production, which will ultimately be used with robust image processing techniques to drive an improved UBT feedback display. Though blade, root, and dorsum movement are known to characterize /r/ production (Boyce et al., 2011; Espy-Wilson et al., 2000; Zhou et al., 2008), excursion of these tongue parts differs across individuals. Here, regional tongue displacements were tracked based on measured motion of local brightness maxima in low-pass-filtered midsagittal ultrasound images, normalized by reference anatomical landmark distances. Preliminary results show that the midsagittal dorsum, root, and blade show more extreme displacements relative to each other for the correct /r/ versus misarticulated /r/. This result is consistent with clinical observations of “humped” error /r/ tongue shapes.
Models and methods for exploring anisotropy and inhomogeneity in vibrating vocal fold tissue
Authors: Oakey Ryan M. , Thomson Scott L.
Published: May 2016

Synthetic vocal fold models have long been used to study features of human voice production that cannot reasonably be studied in vivo. Numerous models have been developed to study different aspects of voice production. Some models have focused, for example, on mimicking geometry or tissue layering while others have been used to study the effect of vibration on live cells. Two aspects of vocal fold structure that have yet to be fully explored are the anisotropic and the inhomogeneous qualities of vocal fold tissue. These features significantly influence vocal fold flow-induced vibratory characteristics. The purpose of this research is to develop and explore models that incorporate anisotropy and inhomogeneity to study their effects on vocal fold vibration. In this presentation, methods and models for studying these features will be discussed; one example is the creation of a fiber matrix via rotary jet spinning that is embedded within silicone vocal fold models to study material anisotropy. Fabrication methodology and model response results will be presented, along with corresponding implications and possibilities for future use in the study of human voice production.
Efficiency of synthetic excitation obtained by interference of ultrasonic waveforms for reducing background noise for laryngeotomee
Authors: Bhat Romilla M. , Lehana Parveen K.
Published: May 2016

Interference pattern of simulated ultrasonic waves using Matlab(free version R2010a) using the laws of acoustics has been used to get excitation in the audio frequency range. Preliminary experiments have been done using different high frequencies and the recordings have been done in Goldwave 5.1 version and then subsequent analysis have been done in Praat to analyze the beat frequency obtained by interfering two high frequency (above 15 kHz) waves. The output thus obtained has been then subjected to Hilbert Transform for envelope detection using Matlab(free version R2010a) to get the audio excitations. These audio excitations are further articulated by the glottal passage for speech synthesis for laryngeotomee or for producing alaryngeal speech. The results of simulation have been further utilised to fabricate a electronic circuit for generation of two continuous ultrasonic waves which are focussed to interfere inside the glottal tract, thereby producing a beat frequency in the audible range and reduce background noise. Index Terms: speech synthesis, ultrasonic waves, laryngeotomee Hilbert transform
Normalizing nasality? Across-speaker variation in acoustical nasality measures
Authors: Styler Will
Published: May 2016

Although vowel nasality has traditionally been investigated using articulatory methods, acoustical methods have been increasingly used in the linguistic literature. However, while these acoustical measures have been shown to be correlated with nasality, their variability across-speakers is less-well investigated. To this end, we examined cross-speaker variation in coarticulatory vowel nasality in a large collection of multi-speaker English data, comparing measurements in CVC and NVN words at two points per vowel. Two known correlates were analyzed: A1-P0, where A1 is the amplitude of the harmonic under F1, and P0 is the amplitude of a low-frequency nasal peak (Chen 1997), and the bandwidth of F1 (Hawkins and Stevens 1985). Speakers varied both in terms of baseline measurements (e.g., the mean measurements in oral versus nasal vowels), and in the oral-nasal range (the measured difference between oral and nasal). This suggests that although analyzing centered within-speaker differences is unproblematic, the comparison of raw nasality measurements across speakers is unlikely to yield meaningful data. Moreover, this suggests that the perception of vowel nasality may require some process of speaker normalization, much like other aspects of vowel perception. Some suggestions for normalizing nasality measurements in research will be offered.
Single hydrophone, passive ranging of tonal sources in shallow water using the waveguide invariant
Authors: Young Andrew , Harms Andrew
Published: May 2016

A statistical method is presented for estimating both the value of the waveguide invariant, β, and the range to a tonal source in shallow water environments. This method requires minimal a priori environmental knowledge. A maximum-likelihood estimate of β is obtained from spectral analysis of a received signal from a tonal source over a known track. The range to a separate tonal source transiting the same shallow-water area is then estimated through a similar maximum-likelihood method, with the additional requirement of a range rate estimate. A recently published technique for estimating range rate through analysis of interference patterns of cross-correlated received time series is compared to a grid-search technique, in the context of evaluating performance of the range estimator. Both simulated and experimental results are presented. Simulated data were obtained using Kraken normal mode code. Experimental results used data from the Swellex ’96 (SW96) experiment. The negative impact of incorrect estimates of source range rate, varying bathymetry, and interfering sources are discussed.
Efficient modeling of room acoustic impulse response by segmentation into early and late components
Authors: Hashemgeloogerdi Sahar , Bocko Mark F.
Published: May 2016

A Room Impulse Response (RIR) has a complex time-frequency structure that can be divided into a number of discrete early reflections followed by a reverberant tail. Many acoustic signal enhancement applications, such as dereverberation and room equalization, require simple yet accurate models to represent an RIR. Parametric modeling of RIR typically approximate the overall response for a given position of a source and receiver inside a room, without considering the fundamental distinction between early reflection (modal region) and late reverberation (statistical region) of an RIR. In this paper, the RIR is estimated in two steps: first, the early reflection component is modeled utilizing fixed pole, parallel orthonormal basis functions to represent the modal behavior of the room. The late reverberation component of an RIR is more statistical in nature with exponentially decaying envelope, exhibiting different decay time constants for different frequencies. Wavelet decomposition using a multi-rate analysis filter bank is applied to model this part of the RIR. An iterative method is used to estimate the parameters of the model from a measured target RIR. The proposed hybrid method provides an accurate representation of an RIR while requiring a smaller number of parameters in comparison to existing methods.
Non-inertial low frequency vector sensor with torsional suspension
Authors: Donskoy Dimitri
Published: May 2016

Conventional low frequency (from 10 Hz) velocity vector sensors utilize inertial approach using neutrally buoyant body with inertial sensor (accelerometer or moving coil geophone) inside. In order to achieve high sensitivity at the low frequencies these sensors must have relatively high inertia (mass). High mass leads to increased size (such as soccer ball) of the sensor in order to satisfy the condition of neutral buoyancy. The developed alternative non-inertial sensor utilizes torsional frictionless and extremely compliant suspension enabling very light and small, yet sensitive with low resonance sensor.
Acoustical Society of America Distinguished Service Citation: Susan B. Blaeser
Authors: Schomer Paul D.
Published: May 2016

The Distinguished Service Citation is awarded to a present or former member of the Society in recognition of outstanding service to the Society.
Acoustical Society of America R. Bruce Lindsay Award: Megan S. Ballard
Authors: Muir Thomas , Wilson Preston
Published: May 2016

The R. Bruce Lindsay Award (formerly the Biennial Award) is presented in the Spring to a member of the Society who is under 35 years of age on 1 January of the year of the Award and who, during a period of two or more years immediately preceding the award, has been active in the affairs of the Society and has contributed substantially, through published papers, to the advancement of theoretical or applied acoustics, or both. The award was presented biennially until 1986. It is now an annual award.
Acoustical Society of America Gold Medal: Whitlow W. L. Au
Authors: Simmons James A.
Published: May 2016

The Gold Medal is presented in the spring to a member of the Society, without age limitation, for contributions to acoustics. The first Gold Medal was presented in 1954 on the occasion of the Society’s Twenty-Fifth Anniversary Celebration and biennially until 1981. It is now an annual award.
Why humans are the high-energy apes
Authors: Gibbons Ann
Published: May 2016

Our metabolism runs faster than that of other apes, likely allowing us to evolve big brains.
Webinar | CRISPR/Cas9 in drug discovery: Applications in target discovery, validation, and hit screening
Authors: Mayr Lorenz , Garippa Ralph
Published: May 2016

The CRISPR/Cas9 system allows for unprecedented ease and control when editing the genome. Its potential impact on drug discovery is vast, including enabling gene and cell replacement therapies, identifying novel drug targets through functional genomic screens, and simplifying the production of disease models using permanent knockouts for validating therapy targets and testing drug efficacy. But in practical terms, how is CRISPR/Cas9 currently being applied, and where might the future challenges and pitfalls be? Furthermore, how do assays based on the new CRISPR/Cas9 technology compare with current screening methodologies, particularly those using small interfering RNA (siRNA)?

View the Webinar
Nongenetic functions of the genome
Authors: Bustin Michael , Misteli Tom
Published: May 2016

The nongenetic roles of the nucleus

The eukaryotic cell nucleus provides a home for the genetic material and accessory proteins. As a physical entity, the nucleus also plays an important role in cell dynamics. Bustin and Misteli Review the impacts that the nucleus can have as a nongenetic force. For example, compacted DNA and the nuclear membrane affect nuclear morphology, the cellular response to mechanical force, cell migration, and cell signaling. Chromatin is not only affected by physical forces in cells but participates in a crosstalk of signaling inside cells.

Science
, this issue p.
10.1126/science.aad6933
Mass-dependent and -independent signature of Fe isotopes in magnetotactic bacteria
Authors: Amor Matthieu , Busigny Vincent , Louvat Pascale , Gélabert Alexandre , Cartigny Pierre , Durand-Dubief Mickaël , Ona-Nguema Georges , Alphandéry Edouard , Chebbi Imène , Guyot François
Published: May 2016

An isotope record of magnetic bacteria

Microorganisms have shaped Earth's oceans and atmosphere over billions of years. Ancient microbes left very little direct morphological evidence of their existence in the rock record, thereby requiring geochemical clues for evidence of their activity. Amor
et al.
show that magnetotactic bacteria impart a distinct isotopic signature to their internal iron nanoparticles. Cultures of a modern magnetic bacterium fractionated
57
Fe isotopes independent of their mass, in contrast to fractionation patterns often observed for other isotopes. Because this signature is not produced abiotically or by other iron-metabolizing bacteria, it could serve as a reliable biomarker of this ancient magnetic microbial lifestyle.

Science
, this issue p.
705
Response to Comment on “Cycling Li-O
2
batteries via LiOH formation and decomposition”
Authors: Liu Tao , Kim Gunwoo , Carretero-González Javier , Castillo-Martínez Elizabeth , Bayley Paul M. , Liu Zigeng , Grey Clare P.
Published: May 2016

Lithium-oxygen (Li-O
2
) batteries cycle reversibly with lithium iodide (LiI) additives in dimethoxyethane (DME) to form lithium hydroxide (LiOH). Viswanathan
et al.
argue that because the standard redox potential of the four-electron (e
−
) reaction, 4OH
–
↔ 2H
2
O + O
2
+ 4
e
–
, is at 3.34 V versus Li
+
/Li, LiOH cannot be removed by the triiodide ion (I
3
–
). However, under nonaqueous conditions, this reaction will occur at a different potential. LiOH also reacts chemically with I
3
–
to form IO
3
–
, further studies being required to determine the relative rates of the two reactions on electrochemical charge.
De novo design of protein homo-oligomers with modular hydrogen-bond network–mediated specificity
Authors: Boyken Scott E. , Chen Zibo , Groves Benjamin , Langan Robert A. , Oberdorfer Gustav , Ford Alex , Gilmore Jason M. , Xu Chunfu , DiMaio Frank , Pereira Jose Henrique , Sankaran Banumathi , Seelig Georg , Zwart Peter H. , Baker David
Published: May 2016

Building with designed proteins

General design principles for protein interaction specificity are challenging to extract. DNA nanotechnology, on the other hand, has harnessed the limited set of hydrogen-bonding interactions from Watson-Crick base-pairing to design and build a wide range of shapes. Protein-based materials have the potential for even greater geometric and chemical diversity, including additional functionality. Boyken
et al.
designed a class of protein oligomers that have interaction specificity determined by modular arrays of extensive hydrogen bond networks (see the Perspective by Netzer and Fleishman). They use the approach, which could one day become programmable, to build novel topologies with two concentric rings of helices.

Science
, this issue p.
680
; see also p.
657
Why pursue the postdoc path?
Authors: Sauermann Henry , Roach Michael
Published: May 2016

Complex, diverse rationales require nuanced policies
Inspired by nature
Authors: Netzer Ravit , Fleishman Sarel J.
Published: May 2016

Designed proteins have structural features resembling those of natural active sites
Complete Genome Sequence of the Larvicidal Bacterium Lysinibacillus sphaericus Strain OT4b.25
Authors: Rey Andrés , Silva-Quintero Laura , Dussán Jenny
Published: May 2016

Lysinibacillus sphaericus
OT4b.25 is a native Colombian strain isolated from coleopteran larvae in an oak forest near Bogotá D.C.; this strain has shown high levels of pathogenic activity against
Culex quinquefasciatus
larvae in laboratory assays compared to that of other members of the same species. Using Pacific Biosciences sequencing technology, we propose a chromosomal contig of 4,665,775 bp that, according to comparative analysis, is highly similar to that of reference strain
L. sphaericus
C3-41.
Whole-Genome Sequence of Vibrio alginolyticus Isolated from the Mucus of the Coral
Fungia danai
in the Andaman Sea, India
Authors: Bhotra Tilothama , Singh Durg V.
Published: May 2016

Vibrio alginolyticus
, a halophilic Gram-negative bacterium, which is found in temperate marine and estuarine environments, is known to cause infections in humans and other organisms. We sequenced the genome of sulfamethoxazole-trimthoprim-positive
V. alginolyticus
strain 4-19 isolated from the mucus of the coral
Fungia danai
in the Andaman Sea, India.
Draft Genome Sequence of the Respiration-Competent Strain Lactobacillus casei N87
Authors: Zotta Teresa , Ricciardi Annamaria , Parente Eugenio , Reale Anna , Ianniello Rocco G. , Bassi Daniela
Published: May 2016

Lactobacillus casei
is used as a starter, adjunct, and/or probiotic culture in the production of fermented and functional foods. Here, we report the draft genome sequence of the respiration-competent strain
L. casei
N87, isolated from infant feces. This genome information may be useful for the study of respiratory metabolism in lactic acid bacteria.
Seeking Sepsis in the Emergency Department- Identifying Barriers to Delivery of the Sepsis 6
Authors: Bentley James , Henderson Susan , Thakore Shobhan , Donald Michael , Wang Weijie
Published: May 2016

The Sepsis 6 is an internationally accepted management bundle that, when initiated within one hour of identifying sepsis, can reduce morbidity and mortality. This management bundle was advocated by the Scottish Patient Safety Programme as part of its Acute Adult campaign launched in 2008 and adopted by NHS Tayside in 2012. Despite this, the Emergency Department (ED) of Ninewells Hospital, a tertiary referral centre and major teaching hospital in Scotland, was displaying poor success in the Sepsis 6.

We therefore set out to improve compliance by evaluating the application of all aspects of the NHS Tayside Sepsis 6 bundle within one hour of ED triage time, to identify what human factors may influence achieving the one hour The Sepsis 6 bundle. This allowed us to tailor a number of specific interventions including educational sessions, regular audit and personal feedback and check list Sepsis 6 sticker. These interventions promoted a steady increase in compliance from an initial rate of 51.0% to 74.3%.

The project highlighted that undifferentiated patients create a challenge in initiating the Sepsis 6. Pyrexia is a key human factor-trigger for recognising sepsis with initial nursing assessment being vital in recognition and identifying the best area (resus) of the department to manage severely septic patients. EDs need to recognise these challenges and develop educational and feedback plans for staff and utilise available resources to maximise the Sepsis 6 compliance.
Improving early childhood literacy and school readiness through Reach Out and Read (ROR) program.
Authors: Thakur Kripa , Sudhanthar Sathyanarayan , Sigal Yakov , Mattarella Nina
Published: May 2016

Reach out and Read program (ROR) prepares young children to succeed in school by partnering with physicians and training them in handing out age appropriate books and to counsel parents about the importance of reading aloud to their children. Children served by ROR enter kindergarten with stronger vocabulary and language skills. The aim of this project was to improve the rate of distribution of books and physician advice about reading, to the families at each well child visit in the age range of six months to five years. This Quality Improvement (QI) project was conducted in a large inner-city pediatric residency clinic serving a lower socio-economic status under-served population. After reviewing the data from the past two years, we noticed that there was a tremendous drop in the percentage of books handed out at well visits and advice given to parents about benefits of reading aloud and self-reporting of parents reading to their child for four or more days in a week. Two goals were established: 1. To increase the rate of distributing books at every well child visit (WCV) from six months to five years of age by at least 80%. 2. To improve the rate of counseling given by the resident physicians to the families by at least 75%. A workflow was created to efficiently distribute books at well visits. A presentation about the ROR program was attended by all the physicians and residents. Reading tips in each exam room were posted to serve as a reminder for all providers and for the parents. A three question survey was collected from the families at the end of their well visit. A total of 210 surveys were collected from parents over a six month period. The percentage of handing out books at all well child visits increased from 30% to 96%. The rate of providers giving advice about the benefits of reading increased from 26% to 87%. The percentage of parents reading to their child greater than four days per week increased from 56% to 80%. Reading aloud is widely recognized as the single most important activity leading to literacy acquisition. With the above interventions, families participating in the ROR model at our clinic were more likely to read to their children, more likely to report reading aloud at bedtime, and to read aloud four or more days per week.
A study of attitudes, beliefs and organisational barriers related to safe emergency oxygen therapy for patients with COPD (chronic obstructive pulmonary disease) in clinical practice and research
Authors: O'Driscoll B Ronan , Bakerly Nawar Diar , Caress Ann-Louise , Roberts June , Gaston Miriam , Newton Mark , Yorke Janelle
Published: May 2016

Background

Patients can be harmed by receiving too little or too much oxygen. There is ongoing disagreement about the use of oxygen in medical emergencies.

Methods

This was a mixed methods study (survey, telephone interviews and focus groups) involving patients, the public and healthcare professionals (HCPs).

Results

62 patients with chronic obstructive pulmonary disease (COPD), 65 members of the public, 68 ambulance crew members, 22 doctors, 22 nurses and 10 hospital managers took part. For five factual questions about oxygen therapy, the average score for correct answers was 28% for patients with COPD, 33% for the general public and 75% for HCPs. The HCPs had an average score of 66% for five technical questions. Patients (79%) and members of the public (68%) were more likely than HCPs (36%) to believe that oxygen was beneficial in most medical emergencies and less likely to have concerns that it might harm some people (35%, 25% and 68%). All groups had complex attitudes about research into oxygen use in medical emergencies. Many participants would not wish for themselves or their loved ones to have their oxygen therapy determined by a randomised protocol, especially if informed consent was not possible in an emergency situation.

Conclusions

We have found low levels of factual knowledge about oxygen use among patients with COPD and the general public and many false beliefs about the potential benefits and harms of using oxygen. HCPs had a higher level of factual knowledge. All groups had complex attitudes towards research into emergency oxygen use.
Monitoring the premalignant potential of Barrett's oesophagus'
Authors: Graham David , Lipman Gideon , Sehgal Vinay , Lovat Laurence B
Published: May 2016

The landscape for patients with Barrett's oesophagus (BE) has changed significantly in the last decade. Research and new guidelines have helped gastroenterologists to better identify those patients with BE who are particularly at risk of developing oesophageal adenocarcinoma. In parallel, developments in endoscopic image enhancement technology and optical biopsy techniques have improved our ability to detect high-risk lesions. Once these lesions have been identified, the improvements in minimally invasive endoscopic therapies has meant that these patients can potentially be cured of early cancer and high-risk dysplastic lesions without the need for surgery, which still has a significant morbidity and mortality. The importance of reaching an accurate diagnosis of BE remains of paramount importance. More work is needed, however. The vast majority of those undergoing surveillance for their BE do not progress towards cancer and thus undergo a regular invasive procedure, which may impact on their psychological and physical well-being while incurring significant cost to the health service. New work that explores cheaper endoscopic or non-invasive ways to identify the at-risk individual provides exciting avenues for research. In future, the diagnosis and monitoring of patients with BE could move away from hospitals and into primary care.
Saving our bacon: changing perceptions of the pig vet
Authors: Webster Grace
Published: May 2016

Over the past few decades, the pig industry and the veterinary role within it has undergone significant change. As part of Veterinary Record's series examining the state of different sectors of the veterinary profession, Grace Webster looks at the challenges facing the pig sector and what the future might hold for the pig veterinarian.
Drained and undrained analyses of cylindrical cavity contractions by bounding surface plasticity
Authors: Chen S.L. , Abousleiman Y.N.
Published: May 2016

This paper develops a rigorous semi-analytical approach for drained–undrained cylindrical cavity contraction problems in bounding surface elastoplastic geomaterials. For undrained situations, the effective radial, tangential, and vertical component stresses can be solved directly from the constitutive governing differential equations as an initial value problem, the excess pore pressure subsequently being determined from the radial equilibrium equation. In contrast, for the drained case the Eulerian radial equilibrium equation must be first transformed into an equivalent one in a Lagrangian description via the introduction of an auxiliary variable, then solved together with the elastoplastic constitutive relation for the three stress components as well as the specific volume. It is observed that during drained–undrained contraction processes, plastic deformations occur immediately as a direct result of employing the bounding surface model, so outside the cavity there exists no purely elastic zone. The computed stress distributions and in particular the stress path prediction through an example analysis capture well the anticipated elastoplastic and failure behaviour of the geomaterials surrounding the cavity. The validity and accuracy of the proposed semi-analytical elastoplastic solutions are justified through comparison with ABAQUS numerical results, and their applicability to the tunnel excavation and wellbore drilling problems is also demonstrated.
Evaluation of spring load restrictions and winter weight premium duration prediction methods in cold regions according to field data
Authors: Asefzadeh Arian , Hashemian Leila , Haghi Negar Tavafzadeh , Bayat Alireza
Published: May 2016

Road pavements in frost-susceptible regions are challenged by frost-thaw induced damages. Spring load restriction (SLR) is intended to reduce road distresses caused by heavily loaded truck traffic. Winter weight premiums (WWP) is applied during early freezing season by increasing the maximum allowable axle loads to reduce the economic difficulties that trucking industries undergo during thaw season. While there are various timelines for applying and removing SLR, this paper reviews three of the SLR prediction models along with a WWP computer simulation and verifies the calculations based on each method using two years of monitored field moisture and temperature data from the fully instrumented integrated road research facility (IRRF) test road in Edmonton, Alberta, Canada. The results revealed that two of the methods showed a significantly better performance in determining the start and end dates of SLR as opposed to the other method. Computer simulations obtained the pavement critical depth beyond which traffic loading did not affect the subgrade material in early freezing season, and collected data aided in estimating the start date of WWP application on the test road. The results were in good agreement with the recommendations suggested by authorities.
Identifying influential nodes in dynamic social networks based on degree-corrected stochastic block model
Authors: Wang Tingting , Dai Weidi , Jiao Pengfei , Wang Wenjun
Published: May 2016

Many real-world data can be represented as dynamic networks which are the evolutionary networks with timestamps. Analyzing dynamic attributes is important to understanding the structures and functions of these complex networks. Especially, studying the influential nodes is significant to exploring and analyzing networks. In this paper, we propose a method to identify influential nodes in dynamic social networks based on identifying such nodes in the temporal communities which make up the dynamic networks. Firstly, we detect the community structures of all the snapshot networks based on the degree-corrected stochastic block model (DCBM). After getting the community structures, we capture the evolution of every community in the dynamic network by the extended Jaccard’s coefficient which is defined to map communities among all the snapshot networks. Then we obtain the initial influential nodes of the dynamic network and aggregate them based on three widely used centrality metrics. Experiments on real-world and synthetic datasets demonstrate that our method can identify influential nodes in dynamic networks accurately, at the same time, we also find some interesting phenomena and conclusions for those that have been validated in complex network or social science.
Quantum coherence in a coupled-cavity array
Authors: Cao De-Wei , Zhang Yixin , Wang Jicheng , Hu Zheng-Da
Published: May 2016

The dynamical properties of quantum coherence in the system of two-coupled-cavities, each of which resonantly interacts with a two-level atom, is investigated via the relative entropy measure. We focus on the coherences for the atom–atom, atom–cavity and cavity–cavity subsystems and find that the dynamical behaviors of these coherences depend largely on the cavity–cavity coupling, which may indicate the Mott insulator-superfluid transition in the thermodynamic limit. We also study the influences of the initial cavity–cavity correlation on the coherences and show that the initial correlation of the cavity–cavity subsystem can enhance the revival ability for the atom–atom and cavity–cavity coherences while reduce that for the atom–cavity coherence. Besides, we demonstrate the qualitative difference of dynamics between coherence and entanglement. Finally, the influences of dissipations including cavity losses and atomic decays on the coherence are explored.
Random walks on semaphore codes and delay de Bruijn semigroups
Authors: Rhodes John , Schilling Anne , Silva Pedro V.
Published: May 2016

We develop a new approach to random walks on de Bruijn graphs over the alphabet [Formula: see text] through right congruences on [Formula: see text], defined using the natural right action of [Formula: see text]. A major role is played by special right congruences, which correspond to semaphore codes and allow an easier computation of the hitting time. We show how right congruences can be approximated by special right congruences.