Compensation for coarticulation reflects gesture perception, not spectral contrast

Talkers temporally overlap the phonetic gestures of speech, a behavior known as coarticulation or coproduction. Gestures characteristically begin in the domain of other, earlier gestures (anticipatory coarticulation) and characteristically end in the domain of later gestures (carryover, or perseveratory, coarticulation). This renders the acoustic speech signal highly context sensitive. However, remarkably, listeners do not, in general, hear it that way. Rather, they compensate for coarticulation. To take a much-studied example, in natural speech, constriction gestures of /l/ and /r/ of a precursor syllable, /al/ or /ar/, can carry over into those of a following /d/ or / / gesture. One outcome can be that the point of constriction achieved during closure for /d/ and / / reflects a blending of their own constriction gestures with those of /r/ or /l/. The pharyngeal constriction for /r/ may pull the point of articulation during the stop consonants back. The tongue tip constriction for /l/ may pull the point of constriction during / / forward. In addition, /r/ is a rounded consonant, and the rounding constriction gesture carries over into the following syllable, further adding to the context sensitivity of the acoustic signals during /da/ and / a/. However, There are other findings of compensation as well. For example, listeners identify more of the ambiguous members along a /ta/-/ka/ continuum as /t/ when they follow /ʃ/ than when they follow /s/ 161 Copyright 2006 Psychonomic Society, Inc. Preparation of the article was supported by Grants HD-01994 and DC-02717 to Haskins Laboratories. I thank Brook Swainson for making the stimuli in Experiment 1 and Doug Honorof both for serving as the second talker in Experiment 1 and for providing expertise for the acoustic analyses reported i

Imitation as a Basis for Phonetic Learning After the Critical Period

Proceedings of the 25th Annual Meeting of the Berkeley Linguistics Society (2000

Articulatory Tradeoffs Reduce Acoustic Variability During American English /r/ Production

Acoustic and articulatory recordings reveal that speakers utilize systematic articulatory tradeoffs to maintain acoustic stability when producing the phoneme /r/. Distinct articulator configurations used to produce /r/ in various phonetic contexts show systematic tradeoffs between the cross-sectional areas of different vocal tract sections. Analysis of acoustic and articulatory variabilities reveals that these tradeoffs act to reduce acoustic variability, thus allowing large contextual variations in vocal tract shape; these contextual variations in turn apparently reduce the amount of articulatory movement required. These findings contrast with the widely held view that speaking involves a canonical vocal tract shape target for each phoneme.National Institute on Deafness and Other Communication Disorders (1R29-DC02852-02, 5R01-DC01925-04, 1R03-C2576-0l); National Science Foundation (IRI-9310518

Functional activation for imitation of seen and heard speech

a b s t r a c t This study examined fMRI activation when perceivers either passively observed or observed and imitated matched or mismatched audiovisual ("McGurk") speech stimuli. Greater activation was observed in the inferior frontal gyrus (IFG) overall for imitation than for perception of audiovisual speech and for imitation of the McGurk-type mismatched stimuli than matched audiovisual stimuli. This unique activation in the IFG during imitation of incongruent audiovisual speech may reflect activation associated with direct matching of incongruent auditory and visual stimuli or conflict between category responses. This study provides novel data about the underlying neurobiology of imitation and integration of AV speech

Band Merging of Spitzer Detections in the SWIRE Fields

The Spitzer Wide-area Infra-Red Extragalactic (SWIRE) Survey has imaged 49 deg^2 of high-Galactic-latitude sky in seven infrared bands spanning wavelengths from 3.6 μm to 160 μm, with beam sizes ranging from about 2″ to 40″. Lists of extracted sources from the individual bands are merged using the Spitzer band merging software. Positions and their uncertainties are used to identify possible band-to-band matches, then decision theory is applied to choose a best match. We present our assessment of band merging reliability based on analysis of the random match rate, and we discuss our application of constraints of multi-band detections and proximity to produce reliable catalogs. We examine the crucial role played by positional uncertainties for extractions made with SExtractor and with Spitzer's Astronomical Point-source EXtraction (APEX) software

international Epidemiology of Carbapenemase-Producing Escherichia Coli

BACKGROUND: Carbapenemase-producing (CP) Escherichia coli (CP-Ec) are a global public health threat. We aimed to describe the clinical and molecular epidemiology and outcomes of patients from several countries with CP-Ec isolates obtained from a prospective cohort. METHODS: Patients with CP-Ec were enrolled from 26 hospitals in 6 countries. Clinical data were collected, and isolates underwent whole-genome sequencing. Clinical and molecular features and outcomes associated with isolates with or without metallo-β-lactamases (MBLs) were compared. The primary outcome was desirability of outcome ranking (DOOR) at 30 days after the index culture. RESULTS: Of the 114 CP-Ec isolates in Consortium on resistance against carbapenems in Klebsiella and other Enterobacterales-2 (CRACKLE-2), 49 harbored an MBL, most commonly blaNDM-5 (38/49, 78%). Strong regional variations were noted with MBL-Ec predominantly found among patients in China (23/49). Clinically, MBL-Ec were more often from urine sources (49% vs 29%), less often met criteria for infection (39% vs 58%, P = .04), and had lower acuity of illness when compared with non-MBL-Ec. Among patients with infection, the probability of a better DOOR outcome for a randomly selected patient with MBL-Ec as compared with non-MBL-Ec was 62% (95% CI: 48.2-74.3%). Among infected patients, non-MBL-Ec had increased 30-day (26% vs 0%; P = .02) and 90-day (39% vs 0%; P = .001) mortality compared with MBL-Ec. CONCLUSIONS: Emergence of CP-Ec was observed with important geographic variations. Bacterial characteristics, clinical presentations, and outcomes differed between MBL-Ec and non-MBL-Ec. Mortality was higher among non-MBL isolates, which were more frequently isolated from blood, but these findings may be confounded by regional variations

Transmisión de Klebsiella pneumoniae resistente a carbapenemes en hospitales de EE.UU.

Antecedentes. La Klebsiella pneumoniae resistente a los carbapenemes (CRKp) es el Enterobacterales resistente a los carbapenemes más prevalente en los Estados Unidos. Se evaluó la agrupación de CRKp en pacientes de hospitales estadounidenses. Métodos. De abril de 2016 a agosto de 2017, 350 pacientes con grupo clonal 258 CRKp se inscribieron en el Consortium on Resistance Against Carbapenems in Klebsiella and other Enterobacteriaceae, un estudio de cohortes prospectivo y multicéntrico. Se construyó un árbol de máxima verosimilitud utilizando RAxML. Los conglomerados estáticos compartían ≤21 polimorfismos de un solo nucleótido (SNP) y un ancestro común más reciente. Los conglomerados dinámicos incorporaron la distancia SNP, el tiempo de cultivo y las tasas de acumulación y transmisión SNP utilizando el programa R TransCluster. Resultados. La mayoría de los pacientes ingresaron desde su domicilio (n=150, 43%) o desde centros de cuidados de larga duración (n=115, 33%). La orina (n=149, 43%) fue el lugar de aislamiento más común. En total, se identificaron 55 conglomerados estáticos y 47 dinámicos en 210 de 350 (60%) y 194 de 350 (55%) pacientes, respectivamente. Aproximadamente la mitad de los clusters estáticos eran idénticos a los dinámicos. Los conglomerados estáticos consistían en 33 (60%) conglomerados intrasistema y 22 (40%) conglomerados intersistema. Los conglomerados dinámicos estaban formados por 32 (68%) conglomerados intrasistema y 15 (32%) conglomerados intersistema y presentaban menos diferencias de SNP que los conglomerados estáticos (8 frente a 9; P=.045; intervalo de confianza [IC] del 95%: -4 a 0). Los conglomerados dinámicos intersistema contenían más pacientes que los conglomerados dinámicos intrasistema (mediana [intervalo intercuartílico], 4 [2, 7] frente a 2 [2, 2]; P=,007; IC del 95%: -3 a 0). Conclusiones. Se identificó una amplia transmisión intrasistémica e intersistémica de CRKp en pacientes estadounidenses hospitalizados. El uso de diferentes métodos para evaluar la similitud genética sólo dio lugar a diferencias menores en la interpretación.Background. Carbapenem-resistant Klebsiella pneumoniae (CRKp) is the most prevalent carbapenem-resistant Enterobacterales in the United States. We evaluated CRKp clustering in patients in US hospitals. Methods. From April 2016 to August 2017, 350 patients with clonal group 258 CRKp were enrolled in the Consortium on Resistance Against Carbapenems in Klebsiella and other Enterobacteriaceae, a prospective, multicenter, cohort study. A maximum likelihood tree was constructed using RAxML. Static clusters shared ≤21 single-nucleotide polymorphisms (SNP) and a most recent common ancestor. Dynamic clusters incorporated SNP distance, culture timing, and rates of SNP accumulation and transmission using the R program TransCluster. Results. Most patients were admitted from home (n=150, 43%) or long-term care facilities (n=115, 33%). Urine (n=149, 43%) was the most common isolation site. Overall, 55 static and 47 dynamics clusters were identified involving 210 of 350 (60%) and 194 of 350 (55%) patients, respectively. Approximately half of static clusters were identical to dynamic clusters. Static clusters consisted of 33 (60%) intrasystem and 22 (40%) intersystem clusters. Dynamic clusters consisted of 32 (68%) intrasystem and 15 (32%) intersystem clusters and had fewer SNP differences than static clusters (8 vs 9; P=.045; 95% confidence interval [CI]: −4 to 0). Dynamic intersystem clusters contained more patients than dynamic intrasystem clusters (median [interquartile range], 4 [2, 7] vs 2 [2, 2]; P=.007; 95% CI: −3 to 0). Conclusions. Widespread intrasystem and intersystem transmission of CRKp was identified in hospitalized US patients. Use of different methods for assessing genetic similarity resulted in only minor differences in interpretation

Telomeric expression sites are highly conserved in trypanosoma brucei

Subtelomeric regions are often under-represented in genome sequences of eukaryotes. One of the best known examples of the use of telomere proximity for adaptive purposes are the bloodstream expression sites (BESs) of the African trypanosome Trypanosoma brucei. To enhance our understanding of BES structure and function in host adaptation and immune evasion, the BES repertoire from the Lister 427 strain of T. brucei were independently tagged and sequenced. BESs are polymorphic in size and structure but reveal a surprisingly conserved architecture in the context of extensive recombination. Very small BESs do exist and many functioning BESs do not contain the full complement of expression site associated genes (ESAGs). The consequences of duplicated or missing ESAGs, including ESAG9, a newly named ESAG12, and additional variant surface glycoprotein genes (VSGs) were evaluated by functional assays after BESs were tagged with a drug-resistance gene. Phylogenetic analysis of constituent ESAG families suggests that BESs are sequence mosaics and that extensive recombination has shaped the evolution of the BES repertoire. This work opens important perspectives in understanding the molecular mechanisms of antigenic variation, a widely used strategy for immune evasion in pathogens, and telomere biology

Clinical Impact of Ceftriaxone Resistance in Escherichia coli Bloodstream Infections: A Multicenter Prospective Cohort Study

BACKGROUND: Ceftriaxone-resistant (CRO-R) Escherichia coli bloodstream infections (BSIs) are common. METHODS: This is a prospective cohort of patients with E coli BSI at 14 United States hospitals between November 2020 and April 2021. For each patient with a CRO-R E coli BSI enrolled, the next consecutive patient with a ceftriaxone-susceptible (CRO-S) E coli BSI was included. Primary outcome was desirability of outcome ranking (DOOR) at day 30, with 50% probability of worse outcomes in the CRO-R group as the null hypothesis. Inverse probability weighting (IPW) was used to reduce confounding. RESULTS: Notable differences between patients infected with CRO-R and CRO-S E coli BSI included the proportion with Pitt bacteremia score ≥4 (23% vs 15%, P = .079) and the median time to active antibiotic therapy (12 hours [interquartile range {IQR}, 1-35 hours] vs 1 hour [IQR, 0-6 hours]; P \u3c .001). Unadjusted DOOR analyses indicated a 58% probability (95% confidence interval [CI], 52%-63%) for a worse clinical outcome in CRO-R versus CRO-S BSI. In the IPW-adjusted cohort, no difference was observed (54% [95% CI, 47%-61%]). Secondary outcomes included unadjusted and adjusted differences in the proportion of 30-day mortality between CRO-R and CRO-S BSIs (-5.3% [95% CI, -10.3% to -.4%] and -1.8 [95% CI, -6.7% to 3.2%], respectively), postculture median length of stay (8 days [IQR, 5-13 days] vs 6 days [IQR, 4-9 days]; P \u3c .001), and incident admission to a long-term care facility (22% vs 12%, P = .045). CONCLUSIONS: Patients with CRO-R E coli BSI generally have poorer outcomes compared to patients infected with CRO-S E coli BSI, even after adjusting for important confounders