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Shrinkage estimation is a fundamental tool of modern statistics, pioneered by Charles Stein upon his discovery of the famous paradox involving the multivariate Gaussian. A large portion of the subsequent literature only considers the efficiency of shrinkage, and that of an associated procedure known as Stein's Unbiased Risk Estimate, or SURE, in the Gaussian setting of that original work. We investigate what extensions to the domain of validity of shrinkage and SURE can be made away from the Gaussian through the use of tools developed in the probabilistic area now known as Stein's method. We show that shrinkage is efficient away from the Gaussian under very mild conditions on the distribution of the noise. SURE is also proved to be adaptive under similar assumptions, and in particular in a way that retains the classical asymptotics of Pinsker's theorem. Notably, shrinkage and SURE are shown to be efficient under mild distributional assumptions, and particularly for general isotropic log-concave measures., improvements and extensions made, such as non-diagonal covariance cases and discrete distributions, additional examples including some elliptical distributions and soft thresholding

Introduction : Most of the previous articulatory studies of stuttering have focussed on the fluent speech of people who stutter. However, to better understand what causes the actual moments of stuttering, it is necessary to probe articulatory behaviors during stuttered speech. We examined the supralaryngeal articulatory characteristics of stuttered speech using real-time structural magnetic resonance imaging (RT-MRI). We investigated how articulatory gestures differ across stuttered and fluent speech of the same speaker. Methods : Vocal tract movements of an adult man who stutters during a pseudoword reading task were recorded using RT-MRI. Four regions of interest (ROIs) were defined on RT-MRI image sequences around the lips, tongue tip, tongue body, and velum. The variation of pixel intensity in each ROI over time provided an estimate of the movement of these four articulators. Results : All disfluencies occurred on syllable-initial consonants. Three articulatory patterns were identified. Pattern 1 showed smooth gestural formation and release like fluent speech. Patterns 2 and 3 showed delayed release of gestures due to articulator fixation or oscillation respectively. Block and prolongation corresponded to either pattern 1 or 2. Repetition corresponded to pattern 3 or a mix of patterns. Gestures for disfluent consonants typically exhibited a greater constriction than fluent gestures, which was rarely corrected during disfluencies. Gestures for the upcoming vowel were initiated and executed during these consonant disfluencies, achieving a tongue body position similar to the fluent counterpart. Conclusion : Different perceptual types of disfluencies did not necessarily result from distinct articulatory patterns, highlighting the importance of collecting articulatory data of stuttering. Disfluencies on syllable-initial consonants were related to the delayed release and the overshoot of consonant gestures, rather than the delayed initiation of vowel gestures. This suggests that stuttering does not arise from problems with planning the vowel gestures, but rather with releasing the overly constricted consonant gestures.

BACKGROUND. Airway management is an essential skill for doctors working in the emergency department (ED). Safety and efficacy are crucial to its success. Analysis of an airway registry can provide feedback that can be used for quality improvement purposes.OBJECTIVES. To examine the first airway registry from an ED in South Africa (SA), a low- to middle-income country (LMIC), and compare the findings with international data.METHODS. A retrospective analysis of 13 months' data from the airway registry of an academic ED with an annual census of 60 000 patients. Data analysed included demographics, indications for intubation, intubator training level, type of intubation device, number of attempts, adverse events, pre-oxygenation methods, and drug and intravenous fluid use.RESULTS. A total of 321 intubations were included. The majority of the patients (71.6%) had non-traumatic indications for intubation. The overall first-pass intubation success (EPS) rate for doctors was 81.8%. Although this rate is lower than the mean rate suggested in an international meta-analysis (84.1%), it is within the 95% confidence interval (80.1 - 87.4%). Overall EPS rates showed no difference between video laryngoscopy (81.7%) compared with direct laryngoscopy (73.3%) (p-value 0.079), although better glottic views were obtained with video laryngoscopy (80.5% were Cormack-Lehane grade 1). Analysis of pre-oxygenation methods found that although sicker patients had received more aggressive pre-oxygenation, e.g. with non-invasive or bag-mask ventilation techniques, they still desaturated more often (35.8% and 62.5%, respectively) than less sick patients who received simple non-rebreather facemask pre-oxygenation (4.5%).CONCLUSIONS. This analysis of the first airway registry from an SA ED highlights that airway management in an LMIC can be performed on par with accepted international standards. It serves as a good baseline for further research into airway management in other LMICs and provides useful feedback for quality improvement purposes.