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Abstract: Undoped and 0.5mol% Ce-doped LiF–LiYF4 eutectic crystals were grown by the micro-pulling-down method at different growth rates. The SEM images of all the eutectic crystals showed LiF with rod-like structure in the LiYF4 matrix. The diameter of the rod phase systematically decreased with the increase of the growth rate. The radioluminescence spectra of cerium doped crystal under alpha-ray excitation showed emission peak at 325nm related to Ce3+ 5d-4f transition. The white part in the cathodoluminescence image is considered to be due to Ce3+ ion in LiYF4 phase, according to the scanning electron microscopy (SEM) image in the same region. [Copyright &y& Elsevier]

Abstract: Undoped and Eu doped SrI2 (Eu:SrI2) single crystals were grown by the modified micro-pulling-down (μ-PD) method and their scintillation properties were investigated. Undoped and Eu:SrI2 single crystals with Eu 1%, 2%, 3% and 5% concentrations were obtained by the modified μ-PD method with the removable chamber system and their crystals with approximately 2mm diameter and 2–3cm length indicated high transparency. Powder X-ray diffraction patterns of grown Eu:SrI2 crystals revealed that the Eu:SrI2 crystals had a single phase of SrI2 structure and similar lattice parameters regardless of Eu concentrations. In the X-ray radioluminescence spectrum of Eu:SrI2 crystal, the emission peak around 430nm which was due to the 5d–4f transition of Eu2+ ion was observed. Light yields, energy resolutions and decay times of grown Eu:SrI2 crystals irradiated under γ-ray were evaluated. [Copyright &y& Elsevier]

Background: Both intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) have been implicated in cardiac allograft rejection. However, there is little information about the relationship between the expression of these adhesion molecules and myocarditis in children. Methods and Results: Immunoreactivities of ICAM-1 and VCAM-1 were examined by enzyme immunoassay in 31 biopsy specimens obtained from 11 pediatric patients with biopsy-proven myocarditis or cardiomyopathy. Five of the 11 patients had clear evidence of acute myocarditis. The other 6 had ECG abnormalities identified by mass screening for heart disease, and subsequently had been histologically diagnosed as having non-specific cardiomyopathy. The period between onset of myocarditis or identification of ECG abnormality and immunohistochemical studies was 23 to 60 days and 8 months to 3 years, respectively. Expression of ICAM-1 and VCAM-1 was assessed by counting ICAM-1- and VCAM-1-positive vessels and dividing by the total number of vessels. ICAM-1 was significantly present on 81% (P<0.01) of myocardial tissue samples in the 5 patients with healing-stage acute myocarditis, and on 45% (P<0.05) in the remaining 6 patients with non-specific cardiomyopathy, compared with 24% in control specimens obtained from right ventricular muscle resected at surgery for tetralogy of Fallot. VCAM-1 was also present on 50% (P<0.05) of the samples from the 5 patients with acute myocarditis, but was not present in those with non-specific cardiomyopathy. Conclusion: This persistent expression of ICAM-1 suggests that myocardial cell damage may persist immunologically for a long period in myocarditis. In addition, immunostaining for these adhesion molecules may be of diagnostic value in clinically silent lymphocytic myocarditis and chronic cardiomyopathy. [ABSTRACT FROM PUBLISHER]

Abstract: The undoped and Ce-doped LiF/LiLuF4 eutectic fibers with various ratios of LuF3 to LiF were grown by the micro-pulling-down method for their application as neutron scintillators with light guiding structure. The differential thermal analysis (DTA) of undoped eutectic materials indicated that the eutectic point of LiF/LiLuF4 was positioned around LiF 80mol%–LuF3 20mol% composition. Some of the as-produced eutectic solids had rod-like regular array structures. This was observed using SEM images of cross-sectional and parallel cuts of the grown solids. In the range of x ≥0.28, the dendrites appeared between the eutectic areas. Ce doped LiF/LiLuF4 eutectic fibers demonstrated two emission peaks around 310 and 326nm in the photoluminescence spectrum, and the decay time of the emission at 326nm was 32.3ns. [Copyright &y& Elsevier]

Abstract: Neutron imaging devices employing a scintillator can be used in various fields, and eutectic crystals can be suitable for the imaging with a fine position resolution of a few hundred micrometers. Since LiF and LaF3 have different refractive indexes of 1.41 and 1.64 at 300nm, respectively, the eutectic crystal is expected to behave as a scintillator with light guiding properties. Thus, the optical properties of Ce-doped LiF/LaF3 eutectic crystal grown by micro-pulling down method were investigated. The light output of LiF/Ce:LaF3 eutectic crystal was relatively small. The emission peaks at 300nm originating from Ce3+ of 5d–4f transition were observed under excitation by UV photons and 5.5MeV alpha rays. Moreover, the photo-luminescence decay time of Ce-doped LiF/LaF3 eutectic crystal was estimated to be 17±1ns. [Copyright &y& Elsevier]