Acoustic surveillance of cough for detecting respiratory disease using artificial intelligence.

Research Question: Can smartphones be used to detect individual and population-level changes in cough frequency that correlate with the incidence of coronavirus disease 2019 (COVID-19) and other respiratory infections?

Methods: This was a prospective cohort study carried out in Pamplona (Spain) between 2020 and 2021 using artificial intelligence cough detection software. Changes in cough frequency around the time of medical consultation were evaluated using a randomisation routine; significance was tested by comparing the distribution of cough frequencies to that obtained from a model of no difference. The correlation between changes of cough frequency and COVID-19 incidence was studied using an autoregressive moving average analysis, and its strength determined by calculating its autocorrelation function (ACF).

Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy.

Deviant stimuli, violating regularities in a sensory environment, elicit the mismatch negativity (MMN), largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience) are minimized.

Effects of prone position and positive end-expiratory pressure on lung perfusion and ventilation.

Objectives: Prone positioning is frequently used during acute respiratory distress syndrome. However, mechanisms by which it improves oxygenation are poorly understood, as well as its interaction with positive end-expiratory pressure. This study was conducted to decipher the respective effects of positive end-expiratory pressure and posture during lung injury on regional lung ventilation, perfusion and recruitment assessed by positron emission tomography.

Effect of activated protein C on pulmonary blood flow and cytokine production in experimental acute lung injury.

Objective: In acute lung injury (ALI) activated protein C (APC) may reopen occluded lung vessels and minimize lung inflammation. We aimed at assessing the effect of APC on regional lung perfusion, aerated lung volume, cytokine production and oxygenation in experimental ALI.

Design And Setting: Prospective, controlled study in an imaging facility.

MRI intensity nonuniformity correction using simultaneously spatial and gray-level histogram information.

A novel approach for correcting intensity nonuniformity in magnetic resonance imaging (MRI) is presented. This approach is based on the simultaneous use of spatial and gray-level histogram information. Spatial information about intensity nonuniformity is obtained using cubic B-spline smoothing.

Creation and application of a simulated database of dynamic [18f]MPPF PET acquisitions incorporating inter-individual anatomical and biological variability.

During the process of validation of a new tracer, estimation of performance and validation of processing algorithms have to be investigated with data sets representative of the ground truth. Because this ground truth is hardly accessible in positron emission tomography (PET), validations of processing algorithms often rely on the use of simulated data sets. Considering that Monte Carlo simulators are very time consuming and are not very easy to use, the building of publicly available databases of simulated PET volumes are becoming highly desirable.

Alveolar recruitment assessed by positron emission tomography during experimental acute lung injury.

Objectives: To compare changes in aerated lung volumes measured by positron emission tomography (PET) and inflation volume-pressure curve (V-P) of the respiratory system, and to evaluate the reliability of PET to assess alveolar recruitment.

Design And Setting: Experimental study in six anesthetized and mechanically ventilated pigs in a PET facility in an experimental university laboratory.

Interventions: Lung injury was induced by oleic acid.

Computation of transmitted and received B1 fields in magnetic resonance imaging.

Computation of B1 fields is a key issue for determination and correction of intensity nonuniformity in magnetic resonance images. This paper presents a new method for computing transmitted and received B1 fields. Our method combines a modified MRI acquisition protocol and an estimation technique based on the Levenberg-Marquardt algorithm and spatial filtering.

Quantitative assessment of regional alveolar ventilation and gas volume using 13N-N2 washout and PET.

Unlabelled: Measurement of alveolar volume (Va) and regional ventilation (a) is crucial to understanding the pathophysiology of acute lung injury and ventilator-induced lung injury. PET has previously been used as a noninvasive, quantitative method to assess a, but formal validation of this technique in experimental lung injury is lacking. This study aims to validate Va and a regional assessment with PET, using inhaled (13)N-N(2) in pigs.

Characterization of PVA cryogel for intravascular ultrasound elasticity imaging.

The present study characterizes the mechanical properties of polyvinyl alcohol (PVA) cryogel in order to show its utility for intravascular elastography. PVA cryogel becomes harder with an increasing number of freeze-thaw cycles, and Young's modulus and Poisson's ratio are measured for seven samples. Mechanical tests were performed on cylindrical samples with a pressure column and on a hollow cylinder with the calculation of an intravascular elastogram.