Investigating dialectal differences using articulography

The present study uses electromagnetic articulography, by which the position of tongue and lips during speech is measured, for the study of dialect variation. By using generalized additive modeling to analyze the articulatory trajectories, we are able to reliably detect aggregate group differences, while simultaneously taking into account the individual variation of dozens of speakers. Our results show that two Dutch dialects show clear differences in their articulatory settings, with generally a more anterior tongue position in the dialect from Ubbergen in the southern half of the Netherlands than in the dialect of Ter Apel in the northern half of the Netherlands. A comparison with formant-based acoustic measurements further reveals that articulography is able to reveal interesting structural articulatory differences between dialects which are not visible when only focusing on the acoustic signal

Lexical frequency co-determines the speed-curvature relation in articulation

The relation between speed and curvature provides a characterization of the spatio-temporal orchestration of kinematic movements. For hand movements, this relation has been reported to follow a power law with exponent -1/3. The same power law has been claimed to govern articulatory movements. We studied the functional form of speed as predicted by curvature using electromagnetic articulography, focusing on three sensors: the tongue tip, the tongue body, and the lower lip. Of specific interest to us was the question of whether the speed-curvature relation is modified by articulatory practice, gauged with words’ frequencies of occurrence. Although analyses imposing linearity a priori indeed supported a power law, relaxation of this linearity assumption revealed that the effect of curvature on speed levels off substantially for lower values of curvature. A modification of the power law is proposed that takes this curvature into account. Furthermore, controlling statistically for number of phones and word duration, we observed that the speed-curvature function was further modulated by an interaction of lexical frequency by curvature, such that for increasing frequency, speed decreased slightly for low curvatures while it increased slightly for high curvatures. The modulation of the balance between speed and curvature by lexical frequency provides further evidence that the skill of articulation improves with practice on a word-to-word basis, and challenges theories of speech production

Head-to-Head Comparison of Two Multi-Locus Sequence Typing (MLST) Schemes for Characterization of Acinetobacter baumannii Outbreak and Sporadic Isolates.

To compare the two Acinetobacter baumannii multi-locus sequence typing (MLST) schemes and to assess their suitability to aid in outbreak analysis we investigated the molecular epidemiology of 99 Acinetobacter baumannii isolates representing outbreak-related and sporadic isolates from 24 hospitals in four different countries (Germany, Poland, Sweden, and Turkey). Pulsed-field gel electrophoresis (PFGE) was used as the reference method to determine the epidemiologic relatedness of isolates and compared to MLST using both the Oxford and Pasteur scheme. Rep-PCR was used to define international clonal lineages (IC). We identified 26 unique outbreak strains and 21 sporadic strains. The majority of outbreaks were associated with carbapenem-resistant A. baumannii harbouring oxacillinase OXA-23-like and corresponding to IC 2. Sequence types (STs) obtained from the Oxford scheme correlate well with PFGE patterns, while the STs of the Pasteur scheme are more in accordance with rep-PCR grouping, but neither one is mirroring completely the results of the comparator. On two occasions the Oxford scheme identified two different STs within a single outbreak where PFGE patterns had only one band difference. The CCs of both MLST schemes were able to define clonal clusters that were concordant with the ICs determined by rep-PCR. IC4 corresponds to the previously described CC15 Pasteur (= CC103 Oxford). It can be concluded that both MLST schemes are valuable tools for population-based studies. In addition, the higher discriminatory power of the Oxford scheme that compares with the resolution obtained with PFGE can often aid in outbreak analysis

Outbreak isolates from six hospitals analysed with PFGE and both MLST schemes.

<p>Outbreak isolates from six hospitals analysed with PFGE and both MLST schemes.</p

Epidemiological characterization of 26 outbreak strains using PFGE, rep-PCR, and MLST.

<p>Epidemiological characterization of 26 outbreak strains using PFGE, rep-PCR, and MLST.</p

International clones and corresponding CCs and STs of both MLST schemes based on the investigation of 99 <i>A</i>. <i>baumannii</i> outbreak and sporadic strains.

<p>International clones and corresponding CCs and STs of both MLST schemes based on the investigation of 99 <i>A</i>. <i>baumannii</i> outbreak and sporadic strains.</p