Volume Averaging of Spectral-Domain Optical Coherence Tomography Impacts Retinal Segmentation in Children

Purpose: To determine the influence of volume averaging on retinal layer thickness measures acquired with spectral-domain optical coherence tomography (SD-OCT) in children. Methods: Macular SD-OCT images were acquired using three different volume acquisition settings (i.e., ART 1, 3, and 9 volumes) in children enrolled in a prospective OCT study. Total retinal, retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, and outer plexiform layer thicknesses were measured around an ETDRS grid using beta version automated segmentation software for the Spectralis. The magnitude of manual segmentation required to correct the automated segmentation was classified as either minor (less than 12 lines adjusted), moderate (\u3e12 andadjusted), severe (\u3e26 and \u3c 48 lines adjusted) or fail (\u3e 48 lines adjusted or could not adjust due to poor image quality). The frequency of each edit classification was assessed for each volume setting. Thickness, paired difference and 95% limits of agreement of each anatomic quadrant were compared across volumes. Results: 75 subjects (median age 11.8 years, range 4.3- 18.5 years) contributed 75 eyes. Less than 5% of the 9 and 3 volume scans required more than minor manual segmentation corrections, compared to 71% of 1 volume scans. The inner (3mm) region demonstrated similar measures across all layers, regardless of volume number. The one volume scans demonstrated greater variability of the RNFL thickness, compared to the other volumes in the outer (6mm) region. Discussion: In children, a minimum acquisition setting of ART 3 for SD-OCT volumes should be obtained to reduce retinal layer segmentation errors

Supercomplex-Associated Cox26 Protein Binds to Cytochrome \u3cem\u3ec\u3c/em\u3e Oxidase

Here we identified a hydrophobic 6.4 kDa protein, Cox26, as a novel component of yeast mitochondrial supercomplex comprising respiratory complexes III and IV. Multi-dimensional native and denaturing electrophoretic techniques were used to identify proteins interacting with Cox26. The majority of the Cox26 protein was found non-covalently bound to the complex IV moiety of the III–IV supercomplexes. A population of Cox26 was observed to exist in a disulfide bond partnership with the Cox2 subunit of complex IV. No pronounced growth phenotype for Cox26 deficiency was observed, indicating that Cox26 may not play a critical role in the COX enzymology, and we speculate that Cox26 may serve to regulate or support the Cox2 protein. Respiratory supercomplexes are assembled in the absence of the Cox26 protein, however their pattern slightly differs to the wild type III–IV supercomplex appearance. The catalytic activities of complexes III and IV were observed to be normal and respiration was comparable to wild type as long as cells were cultivated under normal growth conditions. Stress conditions, such as elevated temperatures resulted in mild decrease of respiration in non-fermentative media when the Cox26 protein was absent

Spin configurations in Co2FeAl0.4Si0.6 Heusler alloy thin film elements

We determine experimentally the spin structure of half-metallic Co2FeAl0.4Si0.6 Heusler alloy elements using magnetic microscopy. Following magnetic saturation, the dominant magnetic states consist of quasi-uniform configurations, where a strong influence from the magnetocrystalline anisotropy is visible. Heating experiments show the stability of the spin configuration of domain walls in confined geometries up to 800 K. The switching temperature for the transition from transverse to vortex walls in ring elements is found to increase with ring width, an effect attributed to structural changes and consequent changes in magnetic anisotropy, which start to occur in the narrower elements at lower temperatures.Comment: 4 pages, 4 figure

Two-Spinon and Orbital Excitations of the Spin-Peierls System TiOCl

We combine high-resolution resonant inelastic x-ray scattering with cluster calculations utilizing a recently derived effective magnetic scattering operator to analyze the polarization, excitation energy, and momentum dependent excitation spectrum of the low-dimensional quantum magnet TiOCl in the range expected for orbital and magnetic excitations (0 - 2.5 eV). Ti 3d orbital excitations yield complete information on the temperature-dependent crystal-field splitting. In the spin-Peierls phase we observe a dispersive two-spinon excitation and estimate the inter- and intra-dimer magnetic exchange coupling from a comparison to cluster calculations

Examining vortex-induced vibration through convolutional neural networks

This research is supported by the projects GA21-31457S ”Fast flow-field prediction using deep neural networks for solving fluid-structure interaction problems”

Strain-dependent magnetic configurations in manganite-titanate heterostructures probed with soft X-ray techniques

We present a detailed study on the strain-induced magnetic domain structure of a (La,Sr)MnO3 thin film epitaxially grown on a BaTiO3 substrate through the use of polarization-dependent X-ray photoemission electron microscopy and X-ray absorption spectroscopy. Angular-dependent measurements allow us to detect vector magnetization on a single-domain scale, and we relate the strain-induced changes in magnetic anisotropy of the ferromagnetic film to the ferroelectric domain structure of the underlying substrate using X-ray magnetic circular and linear dichroism spectro-microscopy. Comparisons to measurements on a nearly strain free film of (La,Sr)MnO3 grown on a (La,Sr)(Al,Ta)O3 substrate illustrate that the BaTiO3 ferroelectric domain structure imprints specific domain sizes and wall orientations in the (La,Sr)MnO3/BaTiO3 artificial multiferroic heterostructure. Furthermore, a change of the BaTiO3 ferroelectric domain structure either with temperature or with applied electric field results in a corresponding change in the (La,Sr)MnO3 ferromagnetic domain structure, thus showing a possible route to obtain room-temperature electric field control of magnetic anisotropy at the nanoscal