Deep Learning Closure of the Navier-Stokes Equations for Transition-Continuum Flows

The predictive accuracy of the Navier-Stokes equations is known to degrade at the limits of the continuum assumption, thereby necessitating expensive and often highly approximate solutions to the Boltzmann equation. While tractable in one spatial dimension, their high dimensionality makes multi-dimensional Boltzmann calculations impractical for all but canonical configurations. It is therefore desirable to augment the Navier-Stokes equations in these regimes. We present an application of a deep learning method to extend the validity of the Navier-Stokes equations to the transition-continuum flows. The technique encodes the missing physics via a neural network, which is trained directly from Boltzmann solutions. While standard DL methods can be considered ad-hoc due to the absence of underlying physical laws, at least in the sense that the systems are not governed by known partial differential equations, the DL framework leverages the a-priori known Boltzmann physics while ensuring that the trained model is consistent with the Navier-Stokes equations. The online training procedure solves adjoint equations, constructed using algorithmic differentiation, which efficiently provide the gradient of the loss function with respect to the learnable parameters. The model is trained and applied to predict stationary, one-dimensional shock thickness in low-pressure argon

Multi-domain analysis and prediction of the light emitted by an inductively coupled plasma jet

Inductively coupled plasma wind tunnels are crucial for replicating hypersonic flight conditions in ground testing. Achieving the desired conditions (e.g., stagnation-point heat fluxes and enthalpies during atmospheric reentry) requires a careful selection of operating inputs, such as mass flow, gas composition, nozzle geometry, torch power, chamber pressure, and probing location along the plasma jet. The study presented herein focuses on the influence of the torch power and chamber pressure on the plasma jet dynamics within the 350 kW Plasmatron X ICP facility at the University of Illinois at Urbana-Champaign. A multi-domain analysis of the jet behavior under selected power-pressure conditions is presented in terms of emitted light measurements collected using high-speed imaging. We then use Gaussian Process Regression to develop a data-informed learning framework for predicting Plasmatron X jet profiles at unseen pressure and power test conditions. Understanding the physics behind the dynamics of high-enthalpy flows, particularly plasma jets, is the key to properly design material testing, perform diagnostics, and develop accurate simulation modelsComment: 22 pages (including figures, appendix, and references); 13 figure

Morphologic study of the pancreas of young and adults alpacas (Vicugna pacos)

El objetivo de este estudio fue realizar una caracterización morfológica del páncreas de alpacas jóvenes (n=9) y adultas (n=5). Para el estudio macroscópico se observó el páncreas in situ reconociendo su forma y relación con otros órganos. Para el estudio microscópico se realizaron cortes histológicos de 5 μm de espesor tiñendo las láminas con hematoxilina de Mayer-Eosina y tricrómico de Masson. El páncreas se divide en tres secciones: cuerpo, lóbulo derecho y lóbulo izquierdo. El lóbulo izquierdo se extiende hacia el plano izquierdo llegando a colindar con el bazo y en mayor proporción al colon descendente. El conducto hepatopancreático presentó dos orígenes: uno donde el conducto hepático se introduce en el parénquima pancreático y lo abandona por el lóbulo derecho como conducto hepatopancreático, y otro donde el conducto pancreático se une con el hepático al emerger del lóbulo derecho para formar el conducto hepatopancreático. En la microscopía se apreció que el parénquima pancreático se encuentra rodeado por una fina capa de tejido conectivo formada en su mayoría por fibras colágenas, que se invaginan dentro del parénquima formando lóbulos y pseudolóbulos, así como células con forma piramidal acomodadas en forma de acinos. Dentro del parénquima se observaron los islotes de Langerhans distribuidos al azar. Los conductos intralobulares e interlobulares se encuentran conformados por epitelio cubico simple, y el conducto hepatopancreático está conformado por una extensa mucosa irregular tapizada de epitelio columnar con microvellosidades. Se concluye que el páncreas de la alpaca muestra diferencias morfológicas con otras especies como rumiantes, herbívoros y carnívoros domésticos.The aim of this study was to morphologically characterize the pancreas of young (n=9) and adult (n=5) alpacas. In the macroscopic study, the pancreas was observed in situ to determine the shape and its relationship with other organs. In the microscopic study, routine histologic procedures were applied and histological sections of 5 μm thick were stained with Mayer-Eosin hematoxylin and Masson trichrome. The pancreas is divided in three sections: body, right lobe and left lobe which extend to the left plane, bordering the spleen and in greater proportion to the descendant colon. The hepatopancreatic duct presented two origins; one where the hepatic duct enters the pancreatic parenchyma and it leaves by the right lobe as the hepatopancreatic duct and another where the pancreatic duct joins with the hepatic duct as it emerges from the right lobe to form the hepatopancreatic duct. In the microscopic evaluation was observed that the pancreatic parenchyma is surrounded by a thin layer of connective tissue formed mostly by collagen fibers, which invaginate within the parenchyma forming lobes and pseudolobules, as well as cells with pyramidal shape accommodated in the form of acini. In the parenchyma was observed the islets of Langerhans randomly distributed. The intralobular and interlobular ducts were formed by simple cubic epithelium, and the hepatopancreatic duct was formed by an extensive irregular mucosa covered with columnar epithelium with microvilli. It is concluded that the alpaca pancreas shows morphological differences with other species such as ruminants, herbivores and domestic carnivores

Promoting Students’ Well-Being and Inclusion in Schools Through Digital Technologies: Perceptions of Students, Teachers, and School Leaders in Italy Expressed Through SELFIE Piloting Activities

Digital technology in its various forms is a significant component of our working environment and lifestyles. However, there is a broad difference between using digital technologies in everyday life and employing them in formal education. Digital technologies have largely untapped potential for improving education and fostering students' well-being and inclusion at school. To bring this to fruition, systemic and coordinated actions involving the whole school community are called for. To help schools exploit the full range of opportunities digital technologies offer for learning, the European Commission has designed and implemented a self-reflection tool called SELFIE (Self-reflection on Effective Learning by Fostering Innovation through Educational Technology). Based on the DigCompOrg conceptual framework, SELFIE encompasses key aspects for effectively integrating digital technologies in school policies and practices. The present study investigates how SELFIE can also support the school community to self-reflect about students' well-being and inclusion. In Italy, the SELFIE online questionnaire has been completed by 24,715 students, 5,690 teachers, and 1,507 school leaders, for a total of 31,912 users from 201 schools (at primary, lower secondary, and upper secondary levels) located in 10 different regions. The complementary data we have collected regarding student well-being and inclusion highlight significant differences in the perceptions on this issue reported by students, teachers, and school leaders. These findings have important implications for facilitating successful practices within the whole school community in order to promote students' well-being and inclusion using educational technologies, as well as for planning future actions following a systemic approach

Case Report: A playful digital-analogical rehabilitative intervention to enhance working memory capacity and executive functions in a pre-school child with autism

Background: Autism Spectrum Disorder (ASD) is often associated with deficits in Working Memory Capacity (WMC) and Executive Functions (EFs), as early as the first years of life. Research has shown that, even young children with ASD, WMC and EF deficits can be effectively addressed through interventions employing digital and/or analogical tools. Early intervention is important because executive dysfunction can negatively impact on the quality of life, both of children and their families. However, very few studies have been carried out involving intervention with pre-schoolers with ASD. To fill this gap, we developed an intervention that promotes pre-schoolers' WMC and EFs by employing both digital apps and analogical playful activities. This study reports on the feasibility of this intervention, which was carried out in a rehabilitative context.Methods: A male pre-schooler diagnosed with ASD was engaged in a total of 17 intervention sessions, all held in a clinical context, over a nine-week period. Outcomes were measured using a battery of pre- and post-treatment tasks focusing on WMC, EFs and receptive language. The clinician who administered the intervention made written observations and noted any improvements in the child's performance emerging from the digital and analogical activities.Results: The pre- and post-test scores for the cognitive tasks revealed qualitative improvements in the following cognitive domains: (a) WMC in the language receptive domain; (b) updating in WMC; (c) inhibition, specifically concerning control of motor response; (d) receptive vocabulary. Furthermore, when monitoring the child's performance, the clinician noted improvement in almost all the playful activities. Particularly notable improvements were observed in interaction with the apps, which the child appeared to find very motivating.Conclusion: This study supports feasibility of a playful digital-analogical intervention conducted by a clinician in a rehabilitation context to promote cognitive abilities in pre-schoolers with ASD. Further studies are needed to establish whether the intervention's effectiveness can be generalized to a broad sample of children with ASD