Effect of polydispersity on the transport and sound absorbing properties of three-dimensional random fibrous structures

Sophisticated numerical approaches can predict the properties of composite nonwovens. However, for polydisperse random fibrous media, we need to identify microstructural descriptors for accurate predictions. We manufactured polydisperse composite felts with different fibrous structures and characterized them using scanning electron microscope images. The images showed a wide distribution of fiber diameters and a decreasing standard deviation of the azimuthal angle of fibers with increasing compression rate. Current models could not capture the evolution of their transport properties with compression rate. Therefore, we developed a fiber network model for the transport processes of transversely isotropic random fibrous media. The model relates the main visco-thermal dissipation mechanisms to the largest channels within the fluid phase, while the smallest channels lead the inertial behaviors. We estimated the viscous and thermal permeabilities from a representative elementary volume (REV) with a volume weighted average diameter, and the viscous and thermal characteristic lengths from a REV with inverse volume weighted average diameter. A unified empirical model was proposed. The model predictions agree with the experimental results.Comment: 29 pages, 19 figure

Pressure flow analysis in the assessment of preswallow pharyngeal bolus presence in dysphagia

Objectives: Preswallow pharyngeal bolus presence is evident in patients with oropharyngeal dysphagia. Pressure flow analysis (PFA) using high resolution manometry with impedance (HRMI) with AIMplot software is a method for objective interpretation of pharyngeal and upper esophageal sphincter (UES) pressures and bolus flow patterns during swallowing. This study aimed to observe alterations in PFA metrics in the event of preswallow pharyngeal bolus presence as seen on videofluoroscopy (VFSS). Methods: Swallows from 40 broad dysphagia patients and 8 controls were recorded with a HRMI catheter during simultaneous VFSS. Evidence of bolus presence and level reached prior to pharyngeal swallow onset was recorded. AIMPlot software derived automated PFA functional metrics. Results: Patients with bolus movement to the pyriform sinuses had a higher SRI, indicating greater swallow dysfunction. Amongst individual metrics, TNadImp to PeakP was shorter and flow interval longer in patient groups compared to controls. A higher pharyngeal mean impedance and UES mean impedance differentiated the two patient groups. Conclusions: This pilot study identifies specific altered PFA metrics in patients demonstrating preswallow pharyngeal bolus presence to the pyriform sinuses. PFA metrics may be used to guide diagnosis and treatment of patients with oropharyngeal dysphagia and track changes in swallow function over time.Lara Ferris, Taher Omari, Margot Selleslagh, Eddy Dejaeger, Jan Tack, Dirk Vanbeckevoort and Nathalie Romme

Once is an Instance, Twice is a Hobby: Multiple Optical and Near-Infrared Changing-Look Events in NGC 5273

NGC 5273 is a known optical and X-ray variable AGN. We analyze new and archival IR, optical, UV, and X-ray data in order to characterize its long-term variability from 2000 to 2022. At least one changing-look event occurred between 2011 and 2014, when the AGN changed from a Type 1.8/1.9 Seyfert to a Type 1. It then faded considerably at all wavelengths, followed by a dramatic but slow increase in UV/optical brightness between 2021 and 2022. We propose that NGC 5273 underwent multiple changing-look events between 2000 and 2022 -- starting as a Type 1.8/1.9, NGC 5273 changes-look to a Type 1 only temporarily in 2002 and again in 2014, reverting back to a Type 1.8/1.9 by 2005 and 2017, respectively. In 2022, it is again a Type 1 Seyfert with optical and NIR broad emission lines. We characterize the changing-look events and their connection to the dynamic accretion and radiative processes in NGC 5273.Comment: 18 pages, 13 figures, 4 tables, submitting to MNRA

Is the metabolic cost of walking higher in people with diabetes?

People with diabetes walk slower and display biomechanical gait alterations compared with controls, but it remains unknown whether the metabolic cost of walking (CoW) is elevated. The aim of this study was to investigate the CoW and the lower limb concentric joint work as a major determinant of the CoW, in patients with diabetes and diabetic peripheral neuropathy (DPN). Thirty-one nondiabetic controls (Ctrl), 22 diabetic patients without peripheral neuropathy (DM), and 14 patients with moderate/severe DPN underwent gait analysis using a motion analysis system and force plates and treadmill walking using a gas analyzer to measure oxygen uptake. The CoW was significantly higher particularly in the DPN group compared with controls and also in the DM group (at selected speeds only) compared with controls, across a range of matched walking speeds. Despite the higher CoW in patients with diabetes, concentric lower limb joint work was significantly lower in DM and DPN groups compared with controls. The higher CoW is likely due to energetic inefficiencies associated with diabetes and DPN reflecting physiological and biomechanical characteristics. The lower concentric joint work in patients with diabetes might be a consequence of kinematic gait alterations and may represent a natural strategy aimed at minimizing the CoW

"Cognitive trajectories during and after electroconvulsive therapy in patients with MDE: Taking different perspectives" (vol152, pg 132, 2022)

Stress-related psychiatric disorders across the life spa

Automatische Impedantie Manometrie (AIM): objectieve diagnostiek van oro-faryngale dysfagie

Dit overzichtsartikel wil het klinisch potentieel aantonen van Automatische Impedantie Manometrie (AIM) als nieuwe, nietradiologische techniek voor screening en diagnostiek van faryngale dysfagie, zijnde slikstoornissen in de mond, keelholte en bovenste slokdarm. Deze AIM-techniek maakt gebruik van een katheter met druksensoren en impedantie-elektroden om slikken kwantitatief te beschrijven. Een geïntegreerde – eerder dan afzonderlijke – analyse van de gemeten druk- en impedantiepatronen die ontstaan bij het doorslikken van een voedselbolus, kan een zinvolle aanvulling zijn op de dynamische beeldvormingsonderzoeken die vandaag de dag als gouden standaard worden gezien. Belangrijke voordelen zijn het objectieve karakter van de techniek en de geautomatiseerde berekening van diverse slikparameters. Een globale maat voor de slikfunctie kan worden bekomen (Slik Risico Index, SRI) en houdt verband met (de ernst van) het aspiratierisico van de patiënt en de aanwezigheid van bolusresidu. Zo kan een accurate detectie van aspiratie met een sensitiviteit van 0,88 en specificiteit van 0,96 niet via radiologisch onderzoek bereikt worden. Verschillende slikparameters zijn ook voldoende gevoelig om veranderingen in voedselconsistentie te detecteren en om de effecten van slikmanoeuvres objectief te beschrijven. Recent werd ook aangetoond dat deze AIM-analyse snel en betrouwbaar kan worden uitgevoerd door clinici met variërende ervaring en opleiding. Bovendien worden in verschillende patiëntengroepen andere patronen van afwijkende slikparameters aangetroffen. Of deze observatie aanleiding kan geven tot specifieke slikdiagnoses en dus meer gerichte behandelingen is momenteel onderwerp van onderzoek

Data mining for software engineering and humans in the loop

The field of data mining for software engineering has been growing over the last decade. This field is concerned with the use of data mining to provide useful insights into how to improve software engineering processes and software itself, supporting decision-making. For that, data produced by software engineering processes and products during and after software development are used. Despite promising results, there is frequently a lack of discussion on the role of software engineering practitioners amidst the data mining approaches. This makes adoption of data mining by software engineering practitioners difficult. Moreover, the fact that experts’ knowledge is frequently ignored by data mining approaches, together with the lack of transparency of such approaches, can hinder the acceptability of data mining by software engineering practitioners. To overcome these problems, this position paper provides a discussion of the role of software engineering experts when adopting data mining approaches. It also argues that this role can be extended to increase experts’ involvement in the process of building data mining models. We believe that such extended involvement is not only likely to increase software engineers’ acceptability of the resulting models, but also improve the models themselves. We also provide some recommendations aimed at increasing the success of experts involvement and model acceptability