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Nigel Weiss was an astrophysicist and applied mathematician, born in South Africa but based in Cambridge for most of his career. He made a number of important contributions to the study of sunspots, where he produced a detailed model of their complex structure. He also made important contributions to theory of the solar 22-year magnetic cycle, using pioneering numerical modelling and drawing attention to the dynamical effects of symmetry breaking and of historic proxy data through observations of radioactive isotopes in tree rings and ice cores. A major part of his work was the numerical and theoretical investigation of many aspects of the interaction of magnetic fields with thermal convection in the Sun and stars. The numerical studies in particular were pioneering in the context of computer resources at that time. He led a talented group of students and postdocs, many of whom have held senior positions in UK and US universities. He combined great physical insight with expertise in numerical computation, nonlinear dynamics and bifurcation theory, and was an inspirational supervisor and mentor, combining high academic standards with an open generous nature. Apart from his work he had a strong interest in twentieth-century art and served on the National Gallery Consultative Group for many years.

Lateral vocalisation is assumed to arise from changes in coronal articulation but is typically characterised perceptually without linking the vocalised percept to a coronal articulation. Therefore, we examined how listeners' perception of coda /l/ as vocalised relates to coronal closure. Perceptual stimuli were acquired by recording laterals produced by six speakers of Australian English using electromagnetic articulography (EMA). Tongue tip closure was monitored for each lateral in the EMA data. Increased incidence of incomplete coronal closure was found in coda /l/ relative to onset /l/. Having verified that the dataset included /l/ tokens produced with incomplete coronal closure—a primary articulatory cue of vocalised /l/—we conducted a perception study in which four highly experienced auditors rated each coda /l/ token from vocalised (3) to non-vocalised (0). An ordinal mixed model showed that increased tongue tip (TT) aperture and delay correlated with vocalised percept, but auditors ratings were characterised by a lack of inter-rater reliability. While the correlation between increased TT aperture, delay, and vocalised percept shows that there is some reliability in auditory classification, variation between auditors suggests that listeners may be sensitive to different sets of cues associated with lateral vocalisation that are not yet entirely understood.

Acoustic studies have shown that in Australian English (AusE), vowel length contrasts are realised through temporal, spectral and dynamic characteristics. However, relatively little is known about the articulatory differences between long and short vowels in this variety. This study investigates the articulatory properties of three long–short vowel pairs in AusE: /iː–ɪ/ beat – bit, /ɐː–ɐ/ cart – cut and /oː–ɔ/ port – pot, using electromagnetic articulography. Our findings show that short vowel gestures had shorter durations and more centralised articulatory targets than their long equivalents. Short vowel gestures also had proportionately shorter periods of articulatory stability and proportionately longer articulatory transitions to following consonants than long vowels. Long–short vowel pairs varied in the relationship between their acoustic duration and the similarity of their articulatory targets: /iː–ɪ/ had more similar acoustic durations and less similar articulatory targets, while /ɐː–ɐ/ were distinguished by greater differences in acoustic duration and more similar articulatory targets. These data suggest that the articulation of vowel length contrasts in AusE may be realised through a complex interaction of temporal, spatial and dynamic kinematic cues.

Gadolinium is a metal used in contrast agents for magnetic resonance imaging. Although gadolinium is widely used in clinical settings, many concerns regarding its toxicity and bioaccumulation after gadolinium-based contrast agent administration have been raised and published over the last decade. To date, most toxicological studies have focused on identifying acute effects following gadolinium exposure, rather than investigating associated toxicity mechanisms. In this study, we employ functional toxicogenomics to assess mechanistic interactions of gadolinium with

Vowel contrasts may be reduced or neutralized before coda laterals in English [Bernard (1985). The Cultivated Australian: Festschrift in Honour of Arthur Delbridge, pp. 319–332; Labov, Ash, and Boberg (2008). The Atlas of North American English, Phonetics and Sound Change (Gruyter Mouton, Berlin); Palethorpe and Cox (2003). International Seminar on Speech Production (Macquaire University, Sydney, Australia)], but the acoustic characteristics of vowel-lateral interaction in Australian English (AusE) rimes have not been systematically examined. Spectral and temporal properties of 16 pre-lateral and 16 pre-obstruent vowels produced by 29 speakers of AusE were compared. Acoustic vowel similarity in both environments was captured using random forest classification and hierarchical cluster analysis of the first three DCT coefficients of F1, F2, and F3, and duration values. Vowels preceding /l/ codas showed overall increased confusability compared to vowels preceding /d/ codas. In particular, reduced spectral contrast was found for the rime pairs /iːl-ɪl/ (feel-fill), /ʉːl-ʊl/ (fool-full), /əʉl-ɔl/ (dole-doll), and /aeɔl-ael/ (howl-Hal). Potential articulatory explanations and implications for sound change are discussed.

A key method for studying articulatory planning at different levels of phonological organization is masked-onset priming. In previous work using that paradigm the dependent variable has been acoustic response time (RT). We used electromagnetic articulography to measure articulatory RTs and the articulatory properties of speech gestures in non-word production in a masked-onset priming experiment. Initiation of articulation preceded acoustic response onset by 199 ms, but the acoustic lag varied by up to 63 ms, depending on the phonological structure of the target. Onset priming affected articulatory response latency, but had no effect on gestural duration, inter-gestural coordination, or articulatory velocity. This is consistent with an account of the masked-onset priming effect in which the computation from orthography of an abstract phonological representation of the target is initiated earlier in the primed than in the unprimed condition. We discuss the implications of these findings for models of speech production and the scope of articulatory planning and execution.

ACS omega 7(38), 34412-34419 (2022). doi:10.1021/acsomega.2c04045, Published by ACS Publications, Washington, DC

Europium is a lanthanide metal that is highly valued in optoelectronics. Even though europium is used in many commercial products, its toxicological profile has only been partially characterized, with most studies focusing on identifying lethal doses in different systems or bioaccumulation in vivo. This paper describes a genome-wide toxicogenomic study of europium in Saccharomyces cerevisiae, which shares many biological functions with humans. By using a multidimensional approach and functional and network analyses, we have identified a group of genes and proteins associated with the yeast responses to ameliorate metal toxicity, which include metal discharge paths through vesicle-mediated transport, paths to regulate biologically relevant cations, and processes to reduce metal-induced stress. Furthermore, the analyses indicated that europium promotes yeast toxicity by disrupting the function of chaperones and cochaperones, which have metal-binding sites. Several of the genes and proteins highlighted in our study have human orthologues, suggesting they may participate in europium-induced toxicity in humans. By identifying the endogenous targets of europium as well as the already existing paths that can decrease its toxicity, we can determine specific genes and proteins that may help to develop future therapeutic strategies.

There has been a recent increase in speech research utilizing data recorded with participants' personal devices, particularly in light of the COVID-19 pandemic and restrictions on face-toface interactions. This raises important questions about whether these recordings are comparable to those made in traditional lab-based settings. Some previous studies have compared the viability of recordings made with personal devices for the clinical evaluation of voice quality. However, these studies rely on simple statistical analyses and do not examine acoustic correlates of voice quality typically examined in the (socio-) phonetic literature (e.g. H1-H2). In this study, we compare recordings from a set of smartphones/laptops and a solid-state recorder to assess the reliability of a range of acoustic correlates of voice quality. The results show significant differences for many acoustic measures of voice quality across devices. Further exploratory analyses demonstrate that these differences are not simple offsets, but rather that their magnitude depends on the value of the measurement of interest. We therefore urge researchers to exercise caution when examining voice quality based on recordings made with participants' devices, particularly when interested in small effect sizes. We also call on the speech research community to investigate these issues more thoroughly. Copyright © 2021 ISCA.

Lanthanides are a series of critical elements widely used in multiple industries, such as optoelectronics and healthcare. Although initially considered to be of low toxicity, concerns have emerged during the last few decades over their impact on human health. The toxicological profile of these metals, however, has been incompletely characterized, with most studies to date solely focusing on one or two elements within the group. In the current study, we assessed potential toxicity mechanisms in the lanthanide series using a functional toxicogenomics approach in baker’s yeast, which shares many cellular pathways and functions with humans. We screened the homozygous deletion pool of 4,291 Saccharomyces cerevisiae strains with the lanthanides and identified both common and unique functional effects of these metals. Three very different trends were observed within the lanthanide series, where deletions of certain proteins on membranes and organelles had no effect on the cellular response to early lanthanides while inducing yeast sensitivity and resistance to middle and late lanthanides, respectively. Vesicle-mediated transport (primarily endocytosis) was highlighted by both gene ontology and pathway enrichment analyses as one of the main functions disturbed by the majority of the metals. Protein–protein network analysis indicated that yeast response to lanthanides relied on proteins that participate in regulatory paths used for calcium (and other biologically relevant cations), and lanthanide toxicity included disruption of biosynthetic pathways by enzyme inhibition. Last, multiple genes and proteins identified in the network analysis have human orthologs, suggesting that those may also be targeted by lanthanides in humans.

In Australian English rimes, coarticulation between coda /l/ and its preceding vowel has the potential to attenuate cues that contribute to phonological vowel contrast. Therefore, vowel-/l/ coarticulation may increase ambiguity between prelateral vowels. We used a vowel identification task to test the effect of vowel-/l/ coarticulation on vowel disambiguation in perception. Listeners categorized vowels in /hVd/ and /hVl/ contexts. Results showed reduced accuracy of vowels before coda /l/ compared to coda /d/, showing that coda /l/ increases vowel disambiguation difficulty. In particular, reduced perceptual contrast was found for the rime pairs /ʉːl-ʊl, aeɔl-ael/ and /əʉl-ɔl/ (e.g., fool-full, howl-Hal, dole-doll). A second experiment tested the effect of reduced perceptual contrast on word recognition. Listeners identified minimal pairs contrasting key vowel pairs in the /CVl/ and /CVd/ contexts. Reduced accuracy and increased response time in /l/ contexts shows that coda /l/ hinders listeners’ ability to identify vowels. The implications of reduced perceptual vowel contrast for compensation for coarticulation and sound change are discussed.

Language-specific maximal size restrictions on syllables have been defined using frames such as moraic structure. In General American English, a trimoraic syllable template makes largely successful predictions about contexts where tense/lax vowel contrasts are neutralised, but neutralisation preceding a coda rhotic has not been adequately explained. We attribute the apparent special properties of coda /ɹ/ to two characteristics of its representation, informed by our articulatory investigation: sequential coordination of dorsal and coronal subsegmental units and a high blending strength specification, corresponding to high coarticulatory dominance. Characteristics of coda laterals are compared. Our approach employs phonological representations where sequencing is encoded directly among subsegments, and coordination is sensitive to strength. Mora assignment is computed over sequencing of subsegments, predicting that complex segments may be bimoraic. The account brings phonotactics for rhymes with postvocalic liquids into line with the trimoraic template, and supports representing coordination and strength at the subsegmental level.

Recent advances in real-time magnetic resonance imaging (RT-MRI) have made it possible to study the anatomy and dynamic motion of the vocal tract during speech production with great detail. The abundance of rich data on speech articulation provided by medical imaging techniques affords new opportunities for speech science, linguistics, clinical and technological research and application development, but also presents new challenges in audio–video data analysis and data modeling. We review techniques used in analysis of articulatory data acquired using RT-MRI, and assess the utility of different approaches for different types of data and research goals.

With social networking enabling the expressions of billions of people to be posted online, sentiment analysis and massive computational power enables systematic mining of information about populations including their affective states with respect to epidemiological concerns during a pandemic. Gleaning rationale for behavioral choices, such as vaccine hesitancy, from public commentary expressed through social media channels may provide quantifiable and articulated sources of feedback that are useful for rapidly modifying or refining pandemic spread predictions, health protocols, vaccination offerings, and policy approaches. Additional potential gains of sentiment analysis may include lessening of vaccine hesitancy, reduction in civil disobedience, and most importantly, better healthcare outcomes for individuals and their communities. In this article, we highlight the evolution of select epidemiological models; conduct a critical review of models in terms of the level and depth of modeling of social media, social network factors, and sentiment analysis; and finally, partially illustrate sentiment analysis using COVID-19 Twitter data.

Articulography and functional neuroimaging are two major tools for studying the neurobiology of speech production. Until now, however, it has generally not been possible to use both in the same experimental setup because of technical incompatibilities between the two methodologies. Here we describe results from a novel articulography system dubbed Magneto-articulography for the Assessment of Speech Kinematics (MASK), used for the first time to obtain kinematic profiles of oro-facial movements during speech together with concurrent magnetoencephalographic (MEG) measurements of neuromotor brain activity. MASK was used to characterise speech kinematics in a healthy adult, and the results were compared to measurements from the same participant with a conventional electromagnetic articulography (EMA) setup. We also characterised speech movement kinematics with MASK in a group of ten typically developing children, aged 8-12 years. Analyses targeted the gestural landmarks of the utterances /ida/, /ila/ and reiterated productions of /pataka/. These results demonstrate that the MASK technique can be used to reliably characterise movement profiles and kinematic parameters that reflect development of speech motor control, together with MEG measurements of brain responses from speech sensorimotor cortex. This new capability sets the stage for cross-disciplinary efforts to understand the developmental neurobiology of human speech production.

Research on the temporal dynamics of /l/ production has focused primarily on mid-sagittal tongue movements. This study reports how known variations in the timing of mid-sagittal gestures are related to para-sagittal dynamics in /l/ formation in Australian English (AusE), using three-dimensional electromagnetic articulography (3D EMA). The articulatory analyses show (1) consistent with past work, the temporal lag between tongue tip and tongue body gestures identified in the mid-sagittal plane changes across different syllable positions and vowel contexts; (2) the lateral channel is largely formed by tilting the tongue to the left/right side of the oral cavity as opposed to curving the tongue within the coronal plane; and, (3) the timing of lateral channel formation relative to the tongue body gesture is consistent across syllable positions and vowel contexts, even as the temporal lag between tongue tip and tongue body gestures varies. This last result is particularly informative with respect to theoretical hypotheses regarding gestural control for /l/s, as it suggests that lateral channel formation is actively controlled as opposed to resulting as a passive consequence of tongue stretching. These results are interpreted as evidence that the formation of the lateral channel is a primary articulatory goal of /l/ production in AusE.

The phonological category "retroflex" is found in many Indo-Aryan languages; however, it has not been clearly established which acoustic characteristics reliably differentiate retroflexes from other coronals. This study investigates the acoustic phonetic properties of Punjabi retroflex /ʈ/ and dental /ʈ̪/ in word-medial and word-initial contexts across /i e a o u/, and in word-final context across /i a u/. Formant transitions, closure and release durations, and spectral moments of release bursts are compared in 2280 stop tokens produced by 30 speakers. Although burst spectral measures and formant transitions do not consistently differentiate retroflexes from dentals in some vowel contexts, stop release duration, and total stop duration reliably differentiate Punjabi retroflex and dental stops across all word contexts and vocalic environments. These results suggest that Punjabi coronal place contrasts are signaled by the complex interaction of temporal and spectral cues.

Long established on stationary devices like traditional personal computers, sensor-enabled intelligent tutoring system (ITS) technology on mobile computing devices (e.g. tablets, smartphones) hope to deliver a personalized tutoring experience tailored to student affect and educational state anywhere, anytime. To achieve these goals, sensor-enabled ITS must overcome technology changes introduced by the mobility of devices such as tablets and smartphones. After a brief contextual presentation and identification of the sensor-enabled ITS technology & research gaps on mobile computing devices, this article discusses opportunities and challenges of the mobile-computing device and proposes a sensor-enabled ITS prototype for mobile devices.

Articulation of liquid consonants in onsets and codas by four speakers of General American English was examined using real-time MRI. Midsagittal tongue posture was compared for laterals and rhotics produced in each syllable margin, adjacent to 13 different vowels and diphthongs. Vowel articulation was examined in words without liquids, before each liquid, and after each liquid, to assess the coarticulatory influence of each segment on the others. Overall, nuclear vocalic postures were more influenced by coda rhotics than onset rhotics or laterals in either syllable margin. Laterals exhibited greater temporal and spatial independence between coronal and dorsal gestures. Rhotics were produced with a variety of speaker-specific postures, but were united by a greater degree of coarticulatory resistance to vowel context, patterns consistent with greater coarticulatory influence on adjacent vowels, and less allophonic variation across syllable positions than laterals.

This study investigated the dynamics of lateral channel formation of /l/ in Australian-accented English (AusE) using 3D electromagnetic articulography (EMA). Coils were placed on the tongue both mid-sagitally and para-sagitally. We varied the vowel precedi /l/ between /I/ and /ae/ /a.g, filbert vs. talbot, and the syllable position of /l/, e.g., /'tael.b-t/ vs. /taeb.l-t/. The articulatory analyses of lateral /l/ show that: (1) the mid-sagittal delay (from the tongue tip gesture to the tongue middle/tongue back gesture) changes across different syllable positions and vowel contexts; (2) the para-sagittal lateralization duration remains the same across syllable positions and vowel contexts; (3) the lateral formation reaches its peak earlier than the mid-sagittal gesture peak; (4) the magnitude of tongue asymmetrical lateralization is greater than the magnitude of tongue curvature in the coronal plane. We discuss these results in light of the temporal dynamics of lateral channel formation. We interpret our results as evidence that the formation of the lateral channel is the primary goal of /l/ production.

Many cellular functions are mediated by protein–protein interaction networks, which are environment dependent. However, systematic measurement of interactions in diverse environments is required to better understand the relative importance of different mechanisms underlying network dynamics. To investigate environment‐dependent protein complex dynamics, we used a DNA‐barcode‐based multiplexed protein interaction assay in Saccharomyces cerevisiae to measure in vivo abundance of 1,379 binary protein complexes under 14 environments. Many binary complexes (55%) were environment dependent, especially those involving transmembrane transporters. We observed many concerted changes around highly connected proteins, and overall network dynamics suggested that “concerted” protein‐centered changes are prevalent. Under a diauxic shift in carbon source from glucose to ethanol, a mass‐action‐based model using relative mRNA levels explained an estimated 47% of the observed variance in binary complex abundance and predicted the direction of concerted binary complex changes with 88% accuracy. Thus, we provide a resource of yeast protein interaction measurements across diverse environments and illustrate the value of this resource in revealing mechanisms of network dynamics.

PurposeReal-time magnetic resonance imaging (MRI) and accompanying analytical methods are shown to capture and quantify salient aspects of apraxic speech, substantiating and expanding upon evidence provided by clinical observation and acoustic and kinematic data. Analysis of apraxic speech errors within a dynamic systems framework is provided and the nature of pathomechanisms of apraxic speech discussed.MethodOne adult male speaker with apraxia of speech was imaged using real-time MRI while producing spontaneous speech, repeated naming tasks, and self-paced repetition of word pairs designed to elicit speech errors. Articulatory data were analyzed, and speech errors were detected using time series reflecting articulatory activity in regions of interest.ResultsReal-time MRI captured two types of apraxic gestural intrusion errors in a word pair repetition task. Gestural intrusion errors in nonrepetitive speech, multiple silent initiation gestures at the onset of speech, and covert (unphonated) articulation of entire monosyllabic words were also captured.ConclusionReal-time MRI and accompanying analytical methods capture and quantify many features of apraxic speech that have been previously observed using other modalities while offering high spatial resolution. This patient's apraxia of speech affected the ability to select only the appropriate vocal tract gestures for a target utterance, suppressing others, and to coordinate them in time.

The low costs of array‐synthesized oligonucleotide libraries are empowering rapid advances in quantitative and synthetic biology. However, high synthesis error rates, uneven representation, and lack of access to individual oligonucleotides limit the true potential of these libraries. We have developed a cost‐effective method called Recombinase Directed Indexing (REDI), which involves integration of a complex library into yeast, site‐specific recombination to index library DNA, and next‐generation sequencing to identify desired clones. We used REDI to generate a library of ~3,300 DNA probes that exhibited > 96% purity and remarkable uniformity (> 95% of probes within twofold of the median abundance). Additionally, we created a collection of ~9,000 individually accessible CRISPR interference yeast strains for > 99% of genes required for either fermentative or respiratory growth, demonstrating the utility of REDI for rapid and cost‐effective creation of strain collections from oligonucleotide pools. Our approach is adaptable to any complex DNA library, and fundamentally changes how these libraries can be parsed, maintained, propagated, and characterized.

USC-TIMIT is an extensive database of multimodal speech production data, developed to complement existing resources available to the speech research community and with the intention of being continuously refined and augmented. The database currently includes real-time magnetic resonance imaging data from five male and five female speakers of American English. Electromagnetic articulography data have also been presently collected from four of these speakers. The two modalities were recorded in two independent sessions while the subjects produced the same 460 sentence corpus used previously in the MOCHA-TIMIT database. In both cases the audio signal was recorded and synchronized with the articulatory data. The database and companion software are freely available to the research community. (C) 2014 Acoustical Society of America.

Dissecting the molecular basis of quantitative traits is a significant challenge and is essential for understanding complex diseases. Even in model organisms, precisely determining causative genes and their interactions has remained elusive, due in part to difficulty in narrowing intervals to single genes and in detecting epistasis or linked quantitative trait loci. These difficulties are exacerbated by limitations in experimental design, such as low numbers of analyzed individuals or of polymorphisms between parental genomes. We address these challenges by applying three independent high-throughput approaches for QTL mapping to map the genetic variants underlying 11 phenotypes in two genetically distant Saccharomyces cerevisiae strains, namely (1) individual analysis of >700 meiotic segregants, (2) bulk segregant analysis, and (3) reciprocal hemizygosity scanning, a new genome-wide method that we developed. We reveal differences in the performance of each approach and, by combining them, identify eight polymorphic genes that affect eight different phenotypes: colony shape, flocculation, growth on two nonfermentable carbon sources, and resistance to two drugs, salt, and high temperature. Our results demonstrate the power of individual segregant analysis to dissect QTL and address the underestimated contribution of interactions between variants. We also reveal confounding factors like mutations and aneuploidy in pooled approaches, providing valuable lessons for future designs of complex trait mapping studies.

SummaryPreselection of compounds that are more likely to induce a phenotype can increase the efficiency and reduce the costs for model organism screening. To identify such molecules, we screened ∼81,000 compounds in Saccharomyces cerevisiae and identified ∼7500 that inhibit cell growth. Screening these growth-inhibitory molecules across a diverse panel of model organisms resulted in an increased phenotypic hit-rate. These data were used to build a model to predict compounds that inhibit yeast growth. Empirical and in silico application of the model enriched the discovery of bioactive compounds in diverse model organisms. To demonstrate the potential of these molecules as lead chemical probes, we used chemogenomic profiling in yeast and identified specific inhibitors of lanosterol synthase and of stearoyl-CoA 9-desaturase. As community resources, the ∼7500 growth-inhibitory molecules have been made commercially available and the computational model and filter used are provided.

Due to its aerodynamic, articulatory, and acoustic complexities, the fricative /s/ is known to require high precision in its control, and to be highly resistant to coarticulation. This study documents in detail how jaw, tongue front, tongue back, lips, and the first spectral moment covary during the production of /s/, to establish how coarticulation affects this segment. Data were obtained from 24 speakers in the Wisconsin x-ray microbeam database producing /s/ in prevocalic and pre-obstruent sequences. Analysis of the data showed that certain aspects of jaw and tongue motion had specific kinematic trajectories, regardless of context, and the first spectral moment trajectory corresponded to these in some aspects. In particular contexts, variability due to jaw motion is compensated for by tongue-tip motion and bracing against the palate, to maintain an invariant articulatory-aerodynamic goal, constriction degree. The change in the first spectral moment, which rises to a peak at the midpoint of the fricative, primarily reflects the motion of the jaw. Implications of the results for theories of speech motor control and acoustic-articulatory relations are discussed.

Moroccan Arabic uses geminate/singleton contrasts in medial position but it is controversial whether it maintains them utterance-initially. To address this issue, we made simultaneous ultrasound and acoustic recordings of five native speakers producing target words containing /t/-/tt/ and /d/-/dd/ contrasts utterance-initially and -medially, 10 times each. The ultrasound data were analysed via a novel method of using pixel-derived principal components and linear discrimination to generate a time-varying articulatory “closure” signal directly from the ultrasound images, without the need for manual tracing. This articulatory signal was subsequently used to measure closure duration by determining gestural landmarks from its velocity function. The results provide clear articulatory evidence that speakers produce utterance-initial singletons versus geminates with significantly different closure durations, although the contrast provides no acoustic evidence of closure duration per se. Rather, our results reveal that speakers realize geminate/singleton contrasts via acoustic dimensions not related to consonant duration: The vowel is significantly longer following geminates than singletons, and the stop bursts have greater amplitude for geminates than singletons. Together these findings provide evidence that the gemination contrast is maintained in initial position in Moroccan Arabic, and challenge traditional assumptions that consonant length contrasts are primarily carried by acoustic closure duration differences.

A structural magnetic resonance imaging study has revealed that pharyngeal articulation varies considerably with voicing during the production of English fricatives. In a study of four speakers of American English, pharyngeal volume was generally found to be greater during the production of sustained voiced fricatives, compared to voiceless equivalents. Though pharyngeal expansion is expected for voiced stops, it is more surprising for voiced fricatives. For three speakers, all four voiced oral fricatives were produced with a larger pharynx than that used during the production of the voiceless fricative at the same place of articulation. For one speaker, pharyngeal volume during the production of voiceless labial fricatives was found to be greater, and sibilant pharyngeal volume varied with vocalic context as well as voicing. Pharyngeal expansion was primarily achieved through forward displacement of the anterior and lateral walls of the upper pharynx, but some displacement of the rear pharyngeal wall was also observed. These results suggest that the production of voiced fricatives involves the complex interaction of articulatory constraints from three separate goals: the formation of the appropriate oral constriction, the control of airflow through the constriction so as to achieve frication, and the maintenance of glottal oscillation by attending to transglottal pressure.

Bioactive compounds are widely used to modulate protein function and can serve as important leads for drug development. Identifying the in vivo targets of these compounds remains a challenge. Using yeast, we integrated three genome-wide gene-dosage assays to measure the effect of small molecules in vivo. A single TAG microarray was used to resolve the fitness of strains derived from pools of (i) homozygous deletion mutants, (ii) heterozygous deletion mutants and (iii) genomic library transformants. We demonstrated, with eight diverse reference compounds, that integration of these three chemogenomic profiles improves the sensitivity and specificity of small-molecule target identification. We further dissected the mechanism of action of two protein phosphatase inhibitors and in the process developed a framework for the rational design of multidrug combinations to sensitize cells with specific genotypes more effectively. Finally, we applied this platform to 188 novel synthetic chemical compounds and identified both potential targets and structure-activity relationships.

PurposeModels of speech production often abstract away from shared physiology in pitch control and lingual articulation, positing independent control of tone and vowel units. We assess the validity of this assumption in Mandarin Chinese by evaluating the stability of lingual articulation for vowels across variation in tone.MethodElectromagnetic articulography was used to track flesh points on the tongue (tip, body, dorsum), lips, and jaw while native Mandarin speakers (n= 6) produced 3 vowels, /pa/, /pi/, /pu/, combined with 4 Mandarin tones: T1 “high,” T2 “rising,” T3 “low,” and T4 “falling.”ResultsConsistent with physiological expectations, tones that begin low, T2 and T3, conditioned a lower position of the tongue body for the vowel /a/. For the vowel /i/, we found the opposite effect, whereby tones that begin low, T2 and T3, conditioned a higher tongue body position.ConclusionsThe physiology of pitch control exerts systematic variation on the lingual articulation of /a/ across tones. The effects of tone on /i/ articulation are in the opposite direction predicted by physiological considerations. Physiologically arbitrary variation of the type observed for /i/ challenges the assumption that phonetic patterns can be determined by independent control of tone (source) and vowel (filter) production units.

Yeasty HIPHOP In order to identify how chemical compounds target genes and affect the physiology of the cell, tests of the perturbations that occur when treated with a range of pharmacological chemicals are required. By examining the haploinsufficiency profiling (HIP) and homozygous profiling (HOP) chemogenomic platforms, Lee et al. (p. 208 ) analyzed the response of yeast to thousands of different small molecules, with genetic, proteomic, and bioinformatic analyses. Over 300 compounds were identified that targeted 121 genes within 45 cellular response signature networks. These networks were used to extrapolate the likely effects of related chemicals, their impact upon genetic pathways, and to identify putative gene functions.

PurposeDifferences in vocal tract morphology have the potential to explain interspeaker variability in speech production. The potential acoustic impact of hard palate shape was examined in simulation, in addition to the interplay among morphology, articulation, and acoustics in real vowel production data.MethodHigh-front vowel production from 5 speakers of American English was examined using midsagittal real-time magnetic resonance imaging data with synchronized audio. Relationships among hard palate morphology, tongue shaping, and formant frequencies were analyzed. Simulations were performed to determine the acoustical properties of vocal tracts whose area functions are altered according to prominent hard palate variations.ResultsSimulations revealed that altering the height and position of the palatal dome alters formant frequencies. Examinations of real speech data showed that palatal morphology is not significantly correlated with any formant frequency but is correlated with major aspects of lingual articulation.ConclusionCertain differences in hard palate morphology can substantially affect vowel acoustics, but those effects are not noticeable in real speech. Speakers adapt their lingual articulation to accommodate palate shape differences with the potential to substantially affect formant frequencies, while ignoring palate shape differences with relatively little acoustic impact, lending support for acoustic goals of vowel production.

In General American English (GAE), tense/lax vowel contrasts occur before syllables ending in /l/ (e.g., peel, pill), but not those ending in /ɹ/ (e.g., peer; no [i]/[ɪ] contrast). No such restrictions occur after a syllable-initial liquid consonant (e.g., lip, leap, rip, reap). This study investigates the hypothesis that these phonotactic asymmetries arise from the interaction of differences in gestural coordination between nuclear vowels and liquid consonants in syllable onset versus coda position (Browman & Goldstein 1995) and differences in blending parameter strength for GAE laterals versus rhotics. A study of speech production by four GAE speakers was conducted using real-time Magnetic Resonance Imaging (Narayanan et al. 2004). Liquid consonants were produced in various vocalic environments and syllable positions (syllable-final, syllable-initial: word-initial and intervocalic). Analysis using a center of gravity metric defined by midsagittal lingual outlines points to greater articulatory stability...

Characteristic tongue postures of 21,478 vowels produced by four speakers of General American English were compared in lexically stressed and unstressed positions to examine patterns of articulation and reduction. Image frames capturing midsagittal vocal tract configurations were reconstructed at the acoustic midpoint of each vowel produced in a 3,450 word forced-aligned transcribed speech corpus (Narayanan et al. 2014). Sixty image sets were constructed, consisting of all exemplars of each contrastive vowel quality of American English, as produced by each speaker: up to 1049 tokens of the most frequent vowel /i/, and 48 tokens of the least frequent vowel /ɔɪ/. Image frames were cropped to a region of interest centred on the tongue dorsum, and linearized into one-dimensional vectors in which pixel intensity corresponds to presence of soft tissue. Principle components analysis was applied to each set of image vectors to examine the distribution and variability of tongue tissue associated with each vowel po...

Using eye-tracking in a visual world paradigm, we sought converging evidence for the time course of Mandarin Chinese tone recognition as predicted by the availability of information in f0 and past results from a gating experiment. Our results showed that tones 1 and 2 are recognized earlier than tone 4, followed by tone 3. With the exception of tone 2, which was recognized earlier than expected, our results are consistent with those found in gating. The speed of tone 2 recognition varied significantly across vowels in our study, part of a broader pattern whereby vowels systematically influenced the time course of tone recognition. Rising tones, tone 2 and tone 3, were recognized earliest when co-produced with /a/. The falling tone, tone 4, was recognized earliest when co-produced with /u/. Intrinsic f0 and spectral cues to tone are discussed as possible explanations for the vowel quality effect.

PurposeAdult human vocal tracts display considerable morphological variation across individuals, but the nature and extent of this variation has not been extensively studied for many vocal tract structures. There exists a need to analyze morphological variation and, even more basically, to develop a methodology for morphological analysis of the vocal tract. Such analysis will facilitate fundamental characterization of the speech production system, with broad implications from modeling to explaining interspeaker variability.MethodA data-driven methodology to automatically analyze the extent and variety of morphological variation is proposed and applied to a diverse subject pool of 36 adults. Analysis is focused on two key aspects of vocal tract structure: the midsagittal shape of the hard palate and the posterior pharyngeal wall.ResultPalatal morphology varies widely in its degree of concavity but also in anteriority and sharpness. Pharyngeal wall morphology, by contrast, varies mostly in terms of concavity alone. The distribution of morphological characteristics is complex, and analysis suggests that certain variations may be categorical in nature.ConclusionMajor modes of morphological variation are identified, including their relative magnitude, distribution, and categorical nature. Implications of these findings for speech articulation strategies and speech acoustics are discussed.

Real-time Magnetic Resonance Imaging (rtMRI) was used to examine mechanisms of sound production by an American male beatbox artist. rtMRI was found to be a useful modality with which to study this form of sound production, providing a global dynamic view of the midsagittal vocal tract at frame rates sufficient to observe the movement and coordination of critical articulators. The subject's repertoire included percussion elements generated using a wide range of articulatory and airstream mechanisms. Many of the same mechanisms observed in human speech production were exploited for musical effect, including patterns of articulation that do not occur in the phonologies of the artist's native languages: ejectives and clicks. The data offer insights into the paralinguistic use of phonetic primitives and the ways in which they are coordinated in this style of musical performance. A unified formalism for describing both musical and phonetic dimensions of human vocal percussion performance is proposed. Audio and video data illustrating production and orchestration of beatboxing sound effects are provided in a companion annotated corpus.