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We report on the fabrication of a novel design of GaAs/(In,Ga)As/GaAs radial nanowire heterostructures on a Si 111 substrate, where, for the first time, the growth of inhomogeneous shells on a lattice mismatched core results in straight nanowires instead of bent. Nanowire bending caused by axial tensile strain induced by the (In,Ga)As shell on the GaAs core is reversed by axial compressive strain caused by the GaAs outer shell on the (In,Ga)As shell. Progressive nanowire bending and reverse bending in addition to the axial strain evolution during the two processes are accessed by in situ by x-ray diffraction. The diameter of the core, thicknesses of the shells, as well as the indium concentration and distribution within the (In,Ga)As quantum well are revealed by 2D energy dispersive x-ray spectroscopy using a transmission electron microscope. Shell(s) growth on one side of the core without substrate rotation results in planar-like radial heterostructures in the form of free standing straight nanowires. [ABSTRACT FROM AUTHOR]

Background: Celiac serology can be transiently elevated in patients with type 1 diabetes mellitus (T1DM) and normalized despite gluten consumption. This study aimed to identify the frequency and predictive factors of spontaneous normalization of anti-tissue transglutaminase (anti-TTG-IgA) antibodies in these patients. Methods: The charts of all patients (≤18 years) with T1DM were retrospectively reviewed from 2012 to 2021 at a tertiary care center in Riyadh, Saudi Arabia. The following data were collected: clinical characteristics of the participants, anti-TTG-IgA-immunoglobulin (Ig) A antibody, and histological findings. The outcome of positive anti-TTG-IgA-IgA in patients with T1DM and the predictive factors for spontaneous normalization were investigated. Results: Of the 1,006 patients with T1DM, 138 (13.7%) had elevated anti-TTG-IgA antibodies, celiac disease was diagnosed in 58/138 (42%) patients, spontaneous normalization of anti-TTG-IgA was observed in 65 (47.1%) patients, and fluctuating anti-TTG-IgA antibodies were seen in 15 (10.9%) patients. The patients with anti-TTG-IgA levels at 3–10 times the upper normal limits (UNL), and those with levels ≥10 times UNL were less likely to have spontaneous normalization of anti-TTG-IgA compared to patients with levels at 1–3 times UNL (hazard ratio [HR] = 0.28, 95% confidence interval [Cl] = 0.13–0.61, P = 0.001, and HR = 0.03, 95% Cl = 0.00–0.19, P < 0.001, respectively). Conclusion: Asymptomatic patients with T1DM with mild elevation of anti-TTG-IgA need not be rushed for invasive endoscopy or exposed to an un-needed gluten-free diet but should rather have a regular follow-up of their celiac serology. [ABSTRACT FROM AUTHOR]

This paper addresses the heat and species transfer in a composite cavity linked with a horizontal channel. The cavity comprises a triangular porous layer and one of its vertical sides is exposed to a high temperature and concentration. The mathematical conservation equations are solved numerically using the Galerkin finite element method. The ranges of Reynolds and Richardson numbers are taken to ascertain laminar flow, Re = 50–250 and Ri = 0.1–100. The size of the porous layer is quantified by the thickness of the porous layer Hp = 0.25–1. The problem is studied for two cases of heat and species sources; the opposing case, when the active side is on the right, and assisting case, when the active side is on the left. Results reveal that for specified conditions, the triangular porous layer increases Nusselt and Sherwood numbers by 30% and 32%, respectively, more than the horizontal porous layer. The opposing case gives maximum convective heat transfer, where for Ri = 0.01, the Nusselt number is higher by 61% and 134% for Re = 50 and 250, respectively, while for Ri = 100, the percentages increase are 67% and 43%. [ABSTRACT FROM AUTHOR]