FO-PINNs: A First-Order formulation for Physics Informed Neural Networks

We present FO-PINNs, physics-informed neural networks that are trained using the first-order formulation of the Partial Differential Equation (PDE) losses. We show that FO-PINNs offer significantly higher accuracy in solving parameterized systems compared to traditional PINNs, and reduce time-per-iteration by removing the extra backpropagations needed to compute the second or higher-order derivatives. Additionally, unlike standard PINNs, FO-PINNs can be used with exact imposition of boundary conditions using approximate distance functions, and can be trained using Automatic Mixed Precision (AMP) to further speed up the training. Through two Helmholtz and Navier-Stokes examples, we demonstrate the advantages of FO-PINNs over traditional PINNs in terms of accuracy and training speedup.Comment: 6 pages, 3 figures, Selected for ML4PS workshop at NeurIPS 202

3D Phase-Field Simulation of Micropore Formation during Solidification: Morphological Analysis

A 3D multiphase-field (PhF) model has been developed in order to study the formation of a micropore constrained to grow in a solid network (i.e., pinching effect). The model accounts for the pressure difference due to capillarity between liquid and gas, the equilibrium condition at triple (solid-liquid-pore) lines, the partitioning and diffusion of dissolved gases such as hydrogen. From the predicted 3D morphology of the pore, entities such as the Interfacial Shape Distribution (ISD) are plotted and analyzed. It is shown that the mean curvature of the pore-liquid surface, and thus also the pressure inside the pore, is uniform. Despite the complex morphology of pores reconstructed using high-resolution X-ray to mography, the present PhF results suggest that a simple pinching model based on a spherical tip growing in between remaining liquid channels is a fairly good approximation

Three-dimensional phase-field simulation of micropore formation during solidification: Morphological analysis and pinching effect

A three-dimensional (3-D) multiphase-field model has been developed in order to study the formation of a micropore constrained to grow in a solid network (i.e. pinching effect). The model accounts for the pressure difference due to capillarity between liquid and gas, the equilibrium condition at triple (solid-liquid-pore) lines, and the partitioning and diffusion of dissolved gases such as hydrogen. From the predicted 3-D morphology of the pore, entities such as the interfacial shape distribution are plotted and analyzed. It is shown that the mean curvature of the pore-liquid surface, and thus also the pressure inside the pore, is uniform. The results are then compared with analytical pinching models. While predicting a similar trend, analytical models tend to underestimate the pore curvature at high solid fractions. Despite the complex morphology of pores reconstructed using high-resolution X-ray tomography, the present phase-field results suggest that a simple pinching model based on a spherical tip growing in between remaining liquid channels is a fairly good approximation. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved

Registry Data Coordinator (RDC): A proper accessible strategy for improving Road Traffic Injury (RTI) Hospital Based Trauma Registry Systems in developing countries and low income countries

Abstract Introduction: Evidence suggested that a significant level of trauma mortality can be prevented using registry system. Aim: This study aimed to improve Kashan Hospital Based Trauma Registry System (KHBTRS) for Road Traffic Injury (RTI). Material and methods: After conducting focus group discussion absence of minimum data set (MDS) and poor data collection process (DCP) were identified as main problems for KHBTRS- RTI. Proposed MDS were surveyed by 20 experts of trauma research center of throughout the Iran. Then approved MDS applied for trauma registry system data base in form of SQL. DCP were reform from prospective data collection (review of medical record) to concurrent (through the interview) approach. Results: Most of participants for MDS approval belonged to clinical group 13(65%). 146 MDS in eighteen main categories were proposed for RTI. The maximum score for each MDS main categories were attributed to body parts injured 220 (100%) and patient vital signs 139 (99.29%) respectively. Pilot testing of KHBTRS- RTI database of 50 (50%) riders indicated fully completeness 50 (100%) for concurrent approach. It was concluded that based on experts’ viewpoints MDS relating to injury nature and place of occurrence have more priority in comparisons to MDS relating to causes of injury. It may attribute to health care providers focus on clinical care and treatment. Conclusion: It was concluded that based on experts’ viewpoints MDS relating to injury nature and place of occurrence have more priority in comparisons to MDS relating to RTI prevention; it may attribute to health care providers focus on clinical care and treatment. To develop injury interventions based on given data, recruitment of professionals as registry data coordinator with specific job description to collect and advocacy of injury external causes data seems imperative. Keywords: data collection, registries, trauma, road traffic accident, data completeness, World Health Organizatio

Effect of reinforced audit and feedback intervention on physician behaviour: a multifaceted strategy for targeting medical record documentation

We investigated the effects of reinforced audit and feedback on the medical record documentation (MRD) of 35 surgical residents at a tertiary university hospital. In three phases (pre intervention, 3 and 9-month post intervention), 525 medical records were assessed. An educational guideline assisting residents to record more accurate MRD was developed. The MRD rate in the pre-intervention and immediate post-intervention phases had changed significantly. The MRD rate in the pre-intervention and 9 months after cessation of intervention was not statistically significant. Reinforced audit and feedback had only a short term effect on MRD. To achieve long lasting change, we suggest residents’ MRD behaviour must be integrated in their periodic clinical performance evaluation and reinforced through positive feedback including incentive mechanisms

Going beyond audit and feedback: towards behaviour-based interventions to change physician laboratory test ordering behaviour

Studies indicate there are a variety of contributing factors affecting physician test ordering behaviour. Identifying these behaviours allows development of behaviour-based interventions. Methods Through a pilot study, the list of contributing factors in laboratory tests ordering, and the most ordered tests, were identified, and given to 50 medical students, interns, residents and paediatricians in questionnaire form. The results showed routine tests and peer or supervisor pressure as the most influential factors affecting physician ordering behaviour. An audit and feedback mechanism was selected as an appropriate intervention to improve physician ordering behaviour. The intervention was carried out at two intervals over a three-month period. Findings There was a large reduction in the number of laboratory tests ordered; from 908 before intervention to 389 and 361 after first and second intervention, respectively. There was a significant relationship between audit and feedback and the meaningful reduction of 7 out of 15 laboratory tests including complete blood count (p = 0.002), erythrocyte sedimentation rate (p = 0.01), C-reactive protein (p = 0.01), venous blood gas (p = 0.016), urine analysis (p = 0.005), blood culture (p = 0.045) and stool examination (p = 0.001). Conclusion The audit and feedback intervention, even in short duration, affects physician ordering behaviour. It should be designed in terms of behaviour-based intervention and diagnosis of the contributing factors in physicians’ behaviour. Further studies are required to substantiate the effectiveness of such behaviour-based intervention strategies in changing physician behaviour

Disposable Platform Provides Visual and Color-Based Point-of-Care Anemia Self-Testing

Anemia, or low blood hemoglobin (Hgb) levels, afflicts 2 billion people worldwide. Currently, Hgb levels are typically measured from blood samples using hematology analyzers, which are housed in hospitals, clinics, or commercial laboratories and require skilled technicians to operate. A reliable, inexpensive point-of-care (POC) Hgb test would enable cost-effective anemia screening and chronically anemic patients to self-monitor their disease. We present a rapid, standalone, and disposable POC anemia test that, via a single drop of blood, outputs color-based visual results that correlate with Hgb levels. METHODS. We tested blood from 238 pediatric and adult patients with anemia of varying degrees and etiologies and compared hematology analyzer Hgb levels with POC Hgb levels, which were estimated via visual interpretation using a color scale and an optional smartphone app for automated analysis. RESULTS. POC Hgb levels correlated with hematology analyzer Hgb levels (r = 0.864 and r = 0.856 for visual interpretation and smartphone app, respectively), and both POC test methods yielded comparable sensitivity and specificity for detecting any anemia (n = 178) (/dl) (sensitivity: 90.2% and 91.1%, specificity: 83.7% and 79.2%, respectively) and severe anemia (n = 10) (/dl) (sensitivity: 90.0% and 100%, specificity: 94.6% and 93.9%, respectively). CONCLUSIONS. These results demonstrate the feasibility of this POC color-based diagnostic test for self-screening/self-monitoring of anemia. TRIAL REGISTRATION. Not applicable. FUNDING. This work was funded by the FDA-funded Atlantic Pediatric Device Consortium, the Georgia Research Alliance, Children\u27s Healthcare of Atlanta, the Georgia Center of Innovation for Manufacturing, and the InVenture Prize and Ideas to Serve competitions at the Georgia Institute of Technology

Safety and effectiveness of high-dose vitamin C in patients with COVID-19: a randomized open-label clinical trial

Background: Vitamin C is an essential water-soluble nutrient that functions as a key antioxidant and has been proven to be effective for boosting immunity. In this study, we aimed to assess the efficacy of adding high-dose intravenous vitamin C (HDIVC) to the regimens for patients with severe COVID-19 disease. Methods: An open-label, randomized, and controlled trial was conducted on patients with severe COVID-19 infection. The case and control treatment groups each consisted of 30 patients. The control group received lopinavir/ritonavir and hydroxychloroquine and the case group received HDIVC (6 g daily) added to the same regimen. Results: There were no statistically significant differences between two groups with respect to age and gender, laboratory results, and underlying diseases. The mean body temperature was significantly lower in the case group on the 3rd day of hospitalization (p = 0.001). Peripheral capillary oxygen saturations (SpO2) measured at the 3rd day of hospitalization was also higher in the case group receiving HDIVC (p = 0.014). The median length of hospitalization in the case group was significantly longer than the control group (8.5 days vs. 6.5 days) (p = 0.028). There was no significant difference in SpO2 levels at discharge time, the length of intensive care unit (ICU) stay, and mortality between the two groups. Conclusions: We did not find significantly better outcomes in the group who were treated with HDIVC in addition to the main treatment regimen at discharge. Trial registration irct.ir (IRCT20200411047025N1), April 14, 2020 © 2021, The Author(s)