21 research outputs found

    SOSORT 2012 consensus paper: reducing x-ray exposure in pediatric patients with scoliosis

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    This 2012 Consensus paper reviews the literature on side effects of x-ray exposure in the pediatric population as it relates to scoliosis evaluation and treatment. Alternative methods of spinal assessment and imaging are reviewed, and strategies for reducing the number of radiographs are developed. Using the Delphi technique, SOSORT members developed consensus statements that describe how often radiographs should be taken in each of the pediatric and adolescent sub-populations

    Symptom-based stratification of patients with primary Sjögren's syndrome: multi-dimensional characterisation of international observational cohorts and reanalyses of randomised clinical trials

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    Background: Heterogeneity is a major obstacle to developing effective treatments for patients with primary Sjögren's syndrome. We aimed to develop a robust method for stratification, exploiting heterogeneity in patient-reported symptoms, and to relate these differences to pathobiology and therapeutic response. / Methods: We did hierarchical cluster analysis using five common symptoms associated with primary Sjögren's syndrome (pain, fatigue, dryness, anxiety, and depression), followed by multinomial logistic regression to identify subgroups in the UK Primary Sjögren's Syndrome Registry (UKPSSR). We assessed clinical and biological differences between these subgroups, including transcriptional differences in peripheral blood. Patients from two independent validation cohorts in Norway and France were used to confirm patient stratification. Data from two phase 3 clinical trials were similarly stratified to assess the differences between subgroups in treatment response to hydroxychloroquine and rituximab. / Findings: In the UKPSSR cohort (n=608), we identified four subgroups: Low symptom burden (LSB), high symptom burden (HSB), dryness dominant with fatigue (DDF), and pain dominant with fatigue (PDF). Significant differences in peripheral blood lymphocyte counts, anti-SSA and anti-SSB antibody positivity, as well as serum IgG, κ-free light chain, β2-microglobulin, and CXCL13 concentrations were observed between these subgroups, along with differentially expressed transcriptomic modules in peripheral blood. Similar findings were observed in the independent validation cohorts (n=396). Reanalysis of trial data stratifying patients into these subgroups suggested a treatment effect with hydroxychloroquine in the HSB subgroup and with rituximab in the DDF subgroup compared with placebo. / Interpretation: Stratification on the basis of patient-reported symptoms of patients with primary Sjögren's syndrome revealed distinct pathobiological endotypes with distinct responses to immunomodulatory treatments. Our data have important implications for clinical management, trial design, and therapeutic development. Similar stratification approaches might be useful for patients with other chronic immune-mediated diseases. / Funding: UK Medical Research Council, British Sjogren's Syndrome Association, French Ministry of Health, Arthritis Research UK, Foundation for Research in Rheumatology

    A multiresolution approach based on MRF and Bak-Sneppen models for image segmentation

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    The two major Markov Random Fields (MRF) based algorithms for image segmentation are the Simulated Annealing (SA) and Iterated Conditional Modes (ICM). In practice, compared to the SA, the ICM provides reasonable segmentation and shows robust behavior in most of the cases. However, the ICM strongly depends on the initialization phase. In this paper, we combine Bak–Sneppen model and Markov Random Fields to define a new image segmentation approach. We introduce a multiresolution technique in order to speed up the segmentation process and to improve the restoration process. Image pixels are viewed as lattice species of Bak–Sneppen model. The a-posteriori probability corresponds to a local fitness. At each cycle, some objectionable species are chosen for a random change in their fitness values. Furthermore, the change in the fitness of each species engenders fitness changes for its neighboring species. After a certain number of iteration, the system converges to a Maximum A Posteriori estimate. In this multireolution approach, we use a wavelet transform to reduce the size of the system

    First Principle Study on Structural, Thermoelectric, and Magnetic Properties of Cubic CdCrO<sub>3</sub> Perovskites: A Comprehensive Analysis

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    The primary objective of contemporary manufacturing is to produce items that are low-cost, environmentally friendly, and energy efficient. This study aimed to investigate compounds that fulfil these criteria, with a focus on CdCrO3. The full potential linearized augmented plane wave program (FP LAPW), as in Wien2K, was employed to examine the structural, electronic, thermodynamic, and transport characteristics of the material. Structural optimization was carried out using generalized gradient approximation (GGA), with lattice constants that were deemed satisfactory based on previous theoretical and experimental results. Calculations of the magnetic characteristics of CdCrO3 show that the Cr atoms are principally responsible for magnetism. The quasi-harmonic Debye model allows for the identification of thermodynamic properties including trends, the relative Debye temperature, thermal expansion parameter, relative volume, and heat capacity at various pressures and temperatures. At constant volume, a heat capacity of 52 J/mol K was determined. The thermoelectric properties were examined using the Boltzmann transport offered by the BoltzTrap program. At room temperature, CdCrO3 had a figure of merit (ZT) value that was almost equal to one, indicating that it may be used to make thermoelectric devices with the highest possible efficiency

    Electronic, magnetic, and optical properties of bulk and (1 1 1)-surfaces of CoMnZnSi quaternary Heusler alloy

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    The structural stability, electronic structure, and magnetic and optical properties of CoMnZnSi quaternary Heusler alloy (QHA) in the bulk and (1 1 1)-slab forms have been investigated by performing density functional theory (DFT) calculations. Formation and cohesive energies, and elastic constants confirm that the bulk CoMnZnSi is chemically and mechanically stable at an equilibrium lattice parameter of 5.81 Å. The calculated elastic constants also indicate that this QHA has ductile and anisotropic features. We investigate and discuss the bonding behavior from charge density distribution and density of states. These calculations in the bulk phase show a perfect half-metallic behavior with an integer value of magnetic moment (4 µB) and a large spin-flip gap of 0.39 eV. On the other hand, the Co (1 1 1) and Si (1 1 1)-slabs exhibit semi-metallic nature at the Fermi level. These results indicate that CoMnZnSi qualifies for spintronic applications. In the bulk and Co (1 1 1), Zn (1 1 1), and Si (1 1 1)-surfaces, the magnetic moment of Co and Mn atoms are ferromagnetically aligned, while the ferrimagnetic alignment of Co with Mn has been found in Mn (1 1 1)-surface. We also investigate the optimal conductivity, dielectric functions, reflectivity, absorption coefficient, refractive index, and loss function to understand the underlying optical properties of this alloy.This is a manuscript of an article published as Paudel, Ramesh, Jing-Chuan Zhu, Moaid K. Hussain, Mohammed Batouche, Muhammad Waqas Qureshi, and Durga Paudyal. "Electronic, magnetic, and optical properties of bulk and (1 1 1)-surfaces of CoMnZnSi quaternary Heusler alloy." Journal of Magnetism and Magnetic Materials 539 (2021): 168425. DOI: 10.1016/j.jmmm.2021.168425. Copyright 2021 Elsevier B.V. DOE Contract Number(s): AC02-07CH11358
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