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We investigated the defect structures of polycrystalline CaKFe4As4 (CaK1144) superconductors by scanning transmission electron microscopy (STEM). The STEM studies revealed the presence of a one-layer CaFe2As2 (∼1 nm size) defect along the ab-plane, as observed in single crystalline CaK1144. Step-like CaFe2As2 defects are also observed. These nanoscale defects generate fine-sized stacking faults, a lattice mismatch, and stress field defects in the matrix of CaK1144 owing to the different sizes. Correlation of the defects in polycrystalline and single crystalline samples suggests that the defects type and their density depend on the synthesis conditions. A self-field critical current density (Jc) of 15.2 kA cm−2 was obtained at 5 K, and the curves were sustained above 30 K with a considerable Jc value of 1.4 kA cm−2. We investigated the relationship between the observed intrinsic defects and the behavior of the field dependence of Jc. The intrinsically intergrown planar defects, even in polycrystalline samples, are expected to be advantageous for various high-field applications of bulk CaK1144 superconductors.

Although nasal septal abscesses are uncommon, their cosmetic complications can be severe. Hence, prompt diagnosis and treatment are important. Here, we report a case of aseptic nasal septal abscess in a patient with proteinase 3-antineutrophil cytoplasmic antibody (PR3-ANCA)-positive ulcerative colitis (UC), in which phlebitis was observed and granulomatosis with polyangiitis (GPA) might co-exist. A 27-year-old female suffered from intermittent abdominal pain and diarrhea for several years. She visited our hospital complaining of worsening swelling and pain in the middle forehead and fever lasting 2 weeks. Physical examination and computed tomography revealed severe swelling of the nasal septum. The patient was diagnosed with nasal septal abscess, and incision drainage and biopsy from the bilateral nasal septum were performed, which showed severe ulcerative neutrophilic mucositis with phlebitis. Simultaneously, blood examination yielded slight positivity for PR3-ANCA. Colonoscopy, including biopsy, revealed severe inflammation without vasculitis nor granuloma, which led to the diagnosis with PR3-ANCA-positive UC. Phlebitis in the nasal mucosa and elevated PR3-ANCA suggested co-existing GPA; hence, she was treated with glucocorticoids and rituximab. Following treatment, the nasal septal abscess and digestive symptoms disappeared. She was discharged on day 25 without symptom recurrence or major nasal deformity. For the prevention of nasal deformity due to persistent inflammation, prompt administration of immunosuppressive therapy should be considered with adequate evaluations for systemic diseases, including UC and GPA.

We investigated the defect structures of polycrystalline CaKFe

Recently, an improvement in the flux pinning performance ofREBa2Cu3O7−δ(REBCO) bulk was achieved employing high energy ultrasonic irradiation (up to 300 W and 60 min) prior to the infiltration-growth process. Here, we demonstrate that a higher ultrasonic power and shorter duration treatment (450 W for 30 min) of theRE2BaCuO5(RE211,RE= Y, Gd) powder produces individual, nanometer-sized and surface damagedRE211 particles (RE211Ultra). We study the growth of YBCO and GdBCO systems via the top-seeded melt-growth method, with the addition of 30 mol% ofRE211Ultra, which were pre-treated by high-energy ultrasonication and compared with the conventional method. Isothermal growth experiments clarified that the addition ofRE211Ultraparticles enables faster and more effective crystal growth via an improved peritectic reaction due to their size in the nanometer range and presence of sharp edges, which are crucial for growing large, single grain bulks ofREBCO. Microstructural investigations by scanning electron microscopy indicated the presence of two differently sizedRE211 inclusions within the bulk GdBCO and YBCO superconductors. All samples showed an onset of superconductivity at ∼92 K or above. Utilizing the effective growth temperature window and the addition ofRE211Ultra, single grain bulks of GdBCO and YBCO were fabricated by the slow-cooling method. The field dependent critical current density (Jc) of the bulk samples usingRE211Ultrawere found to exhibit superior performance over the standard GdBCO/YBCO samples due to significant changes of sample growth and of their microstructures. Here, we discuss various factors affecting the addition ofRE211Ultraon the development of the microstructure, growth of bulk, single grain materials and further, the superconducting properties of differentREBCO superconductors.

We report the synthesis, crystal structure, and optical properties of a new layered perovskite oxychloride, Ba3Y2O5Cl2. The structural and electronic properties of the compound were studied and compared with those of related compounds, Ba3RE2O5Cl2 (RE = Sc, Gd, and Lu). Furthermore, the luminescence properties due to Eu-doping were investigated. Polycrystalline Ba3Y2O5Cl2 samples were successfully synthesized by a solid-state reaction. The space group of the compound was I4/mmm and the lattice constants were a = 4.3971(8) A and c = 24.848(5) A. The Y atom in this compound shifted toward the apical oxygen site owing to the asymmetric coordination of O and Cl. Moreover, large anisotropic displacements were observed at the O sites. The direct bandgap of the compound was 5.4 eV. As Y3+ ions with a distorted octahedron have an asymmetric coordination environment, both magnetic and electric dipole transitions were observed by doping Eu3+ to Y3+ sites. Ba3Y2O5Cl2:Eu 4% also showed a high internal quantum yield (IQY) (>70%). Therefore, considering the photoluminescence spectra and high IQY, this compound is a potential host lattice for optical materials.

A 70-year-old man presented with right mandibular pain and history of right mandibular third molar extraction 20 months back. Examination revealed purulence, exposed bone, and mental nerve hypoesthesia. He was previously prescribed zoledronate to treat bone metastases from pulmonary adenocarcinoma. PET/CT images taken 5 months before the first visit demonstrated increased mandibular FDG uptake. The inflammation remained symptomatic despite zoledronate discontinuation and antibiotic administration, with left mandibular bone exposure. SPECT/CT images demonstrated increased MDP uptake and bilateral mandibular bone destruction. Mandibular resection and pathological investigation revealed a sequestrum, indicating chronic osteomyelitis, leading to diagnosis of ARONJ (stages III and I).

Electronic structures of electron- and hole-doped ${\mathrm{BaFe}}_{2}{\mathrm{As}}_{2}$ and nondoped ${\mathrm{SrFe}}_{2}{\mathrm{As}}_{2}$ have been studied systematically by x-ray emission spectroscopy at Fe and As $K$-absorption edges. The electron and hole doping causes slight increase of the integrated absolute difference (IAD) values of the Fe $K\ensuremath{\beta}$ x-ray emission spectra which correlate to the local magnetic moment. Pressure decreases the IAD values and local magnetic moment, and induces the lower-spin states in these compounds. The pre-edge peak intensity of the XAS spectra at the Fe $K$-absorption edge increases with pressure in both compounds. This indicates an increase of the Fe $3d$--As $4p$ hybridization. It was found that pressure induced a discontinuous increase of the prepeak intensity of the PFY-XAS spectra at the As $K$-absorption edge at low pressures in the ${\mathrm{BaFe}}_{2}{\mathrm{As}}_{2}$ systems. Our results may suggest that the Fe $3d$--As $4p$ hybridization plays a key role in suppressing the AFM order by the doping or pressure and fluctuation of the local magnetic moment and the electron-electron correlation may also play a role on the physical properties of the iron superconductors.

The aim of this study was to determine the efficacy of cyclophosphamide (CY) on anti-neutrophil cytoplasmic antibody (ANCA)-positive microscopic polyangiitis (MPA) with renal involvement in Japanese patients. Eighty-two patients with newly diagnosed ANCA-positive MPA were enrolled in this retrospective study. Patients were divided into two groups based on whether they received combination therapy with a corticosteroid (CS) plus CY (CY group) or CS alone or with other therapies (non-CY group). The primary outcome was defined as the combination of death and end-stage renal disease (ESRD). The CY and non-CY groups included 29 and 53 patients, respectively. In the non-CY group, 31 patients were treated with CS alone, and 22 with a combination of CS and other therapeutics. The percentage of males and mean Birmingham vasculitis activity scores were higher in the CY group than those in the non-CY group, but other factors such as age, serum creatinine, serum albumin, or CRP at baseline were equivalent in the two groups. No differences were observed in remission rates using induction therapy for the two groups. However, the survival rate 5 years after induction therapy was lower in the CY group than in the non-CY group (0.50 vs. 0.73; P = 0.041), although the hazard ratio of CY for the primary outcome adjusted for all confounding factors was 1.321 [95 % confidence interval (CI), 0.662–2.637; P = 0.171]. CY may not have an additive effect on induction therapy with CS for Japanese patients with renal vasculitis associated with ANCA-positive MPA.

We developed liquid-hydrogen (LH2) level sensors with Ba(Fe1-x Co x )2As2 superconducting wires (Co-Ba122 wires) as their detection elements. We fabricated Co-Ba122 wires with different Co concentrations x by using the powder-in-tube method. The superconducting transition temperatures of the wires were successfully controlled in the range of 20–25 K by changing x from 0.06 to 0.10. The resistance–temperature curves of the wires exhibited sharp superconducting transitions with widths of 0.5–1.0 K. In addition, we performed an operation test of the Co-Ba122 level sensors with LH2. Close correspondence between the output resistance and the actual LH2 level was observed for a sensor equipped with x = 0.09 wire, demonstrating that this sensor can accurately measure LH2 levels.

We report the first superconducting tape using an iron-based superconductor (Sr,Na)Fe2As2 fabricated by the powder-in-tube (PIT) technique. Polycrystalline (Sr1−x Na x )Fe2As2 (x = 0.55), which we recently succeeded in synthesizing, was used as the starting powder. First, a silver (Ag) tube was groove-rolled into a square wire. The wire was then flat-rolled into tape form, followed by uniaxial cold pressing. The heat-treated tape exhibits a sharp superconducting transition at 34.5 K. Large transport critical current densities (J c) of over 1.0 × 104 A cm−2 are achieved at 20 K under a magnetic field of 2.5 T. J c at 4.2 K, as estimated from magnetic hysteresis curves, is 1.0 × 105 A cm−2 in 2.0 T, which is comparable to the transport J c reported for (AE,K)Fe2As2 (AE = Ba or Sr) tapes. SEM-EDX observations indicate that some Ag and As-rich material is present between (Sr,Na)Fe2As2 grains, even though no Ag was added to the starting powder. This Ag and As-rich material may strengthen grain connectivity and help to improve the transport J c.