32 research outputs found

    Application of Sturm's theorem to marginal stable circular orbits of a test body in spherically symmetric and static spacetimes

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    In terms of Sturm's theorem, we reexamine a marginal stable circular orbit (MSCO) such as the innermost stable circular orbit (ISCO) of a timelike geodesic in any spherically symmetric and static spacetime. MSCOs for some of exact solutions to the Einstein's equation are discussed. Strum's theorem is explicitly applied to the Kottler (often called Schwarzschild-de Sitter) spacetime. Moreover, we analyze MSCOs for a spherically symmetric, static and vacuum solution in Weyl conformal gravity.Comment: 6 pages, 1 figure, accepted by EPL (Europhysics Letters). arXiv admin note: text overlap with arXiv:1410.626

    Cervical Symmetric Dumbbell Ganglioneuromas Causing Severe Paresis

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    We report an extremely rare case with bilateral and symmetric dumbbell ganglioneuromas of the cervical spine in an elderly patient. A 72-year-old man came by ambulance to our hospital due to progressive incomplete paraplegia. Magnetic resonance imaging demonstrated bilateral symmetric dumbbell tumors at the C1/2 level. We performed total resection of the intracanalar tumor, aiming at complete decompression of the spinal cord, and partial and subtotal resection of foraminal outside portions. Histopathological examination of the surgical specimen indicated the tumor cells to be spindle cells with the presence of ganglion cells and no cellular pleomorphism, suggesting a diagnosis of ganglioneuroma. Although the surgery was not curative, the postoperative course was uneventful and provided a satisfactory outcome. This is the fourth known case of cervical ganglioneuromas of the bilateral symmetric dumbbell type

    経動脈的化学塞栓術における予防的抗菌薬と肝膿瘍発症の関連 : 後方視的コホート研究

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    Objectives: Clinical evidence on prophylactic antibiotics for transarterial chemoembolization (TACE) to prevent liver abscess is limited because liver abscess is a rare event. This study aimed to analyse the association between prophylactic antibiotic use for TACE and the occurrence of liver abscess after TACE. Methods: Using the nationwide Diagnosis Procedure Combination database in Japan, we retrospectively identified patients who underwent TACE for hepatic cancer between July 2010 and March 2017. The primary outcome was liver abscess requiring procedural intervention within 30 days of TACE. Secondary outcomes included 30-day in-hospital mortality and length of stay. Propensity score matching was performed to adjust for potential confounding factors and compare outcomes between patients with and without prophylactic antibiotics. Results: Among 167 544 eligible patients, 134 712 received antibiotics and 32 832 did not. In the matched cohort of 29 211 pairs, the proportion of patients with liver abscess requiring procedural intervention was significantly lower in the antibiotics group than in the no-antibiotics group (0.08% vs. 0.22%, p 0.001; relative risk (95% confidence interval), 0.35 (0.22-0.57); absolute risk reduction, 0.0014 (0.0008-0.0021); and number needed to treat, 696 (476-1223)). There was no significant difference in 30-day in-hospital mortality between the groups. The length of stay was longer in the antibiotics group than in the no-antibiotics group (median, 10 vs. 9 days, p < 0.001). Conclusions: Prophylactic antibiotic use in patients undergoing TACE was associated with a reduced occurrence of liver abscess requiring procedural intervention.博士(医学)・甲第794号・令和3年6月25日Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved

    Prenatal diagnosis of severe mitochondrial diseases caused by nuclear gene defects: a study in Japan

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    Prenatal diagnoses of mitochondrial diseases caused by defects in nuclear DNA (nDNA) or mitochondrial DNA have been reported in several countries except for Japan. The present study aimed to clarify the status of prenatal genetic diagnosis of mitochondrial diseases caused by nDNA defects in Japan. A comprehensive genomic analysis was performed to diagnose more than 400 patients, of which, 13 families (16 cases) had requested prenatal diagnoses. Eight cases diagnosed with wild type homozygous or heterozygous variants same as either of the heterozygous parents continued the pregnancy and delivered healthy babies. Another eight cases were diagnosed with homozygous, compound heterozygous, or hemizygous variants same as the proband. Of these, seven families chose to terminate the pregnancy, while one decided to continue the pregnancy. Neonatal- or infantile-onset mitochondrial diseases show severe phenotypes and lead to lethality. Therefore, such diseases could be candidates for prenatal diagnosis with careful genetic counseling, and prenatal testing could be a viable option for families

    A Luminescent Dinuclear Eu-III/Tb-III Complex with LMCT Band as a Single-Molecular Thermosensor

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    Temperature-dependent luminescence of a dinuclear Eu-III/Tb-III complex with a seven-coordinate structure is demonstrated. The dinuclear complex is composed of two lanthanide ions, six tetramethylheptanedionate ligands, and a bidentate phosphine oxide linker ligand. The dinuclear structure of the complex was characterized by single-crystal XRD. Intrinsic 4f-4f emission quantum yields of the dinuclear Eu-III and Tb-III complexes were 66 and 61%, respectively. The luminescence color of the dinuclear Eu-III/Tb-III complex changed from red to green with increasing temperature. The thermosensing range based on the ratio of luminescence intensity (A(Eu)/A(Tb)) was 100-450K. The temperature-dependent luminescence is due to the presence of a ligand-to-metal charge-transfer state

    Marginally stable circular orbit of a test body in spherically symmetric and static spacetimes

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    We study a marginally stable circular orbit (MSCO) such as the innermost stable circular orbit (ISCO) of a timelike geodesic in any spherically symmetric and static spacetime. It turns out that the metric components are separable from the constants of motion along geodesics. We show also that a metric component grrg_{rr} with a radial coordinate rr does not affect MSCOs. This suggests that, as a test of gravity, any ISCO measurement may be put into the same category as gravitational redshift experiments. MSCOs for exact solutions to the Einstein's equation are also mentioned.Comment: This paper has been withdrawn by the authors, because the main motivation (a new formulation for MSCOs) has disappeare

    Seven-Coordinate Luminophores: Brilliant Luminescence of Lanthanide Complexes with C-3v Geometrical Structures

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    Enhanced luminescence properties of mononuclear lanthanide complexes with asymmetric seven-coordination structures are reported for the first time. The lanthanide complexes are composed of a lanthanide ion (Eu-III or Tb-III), three tetramethyl heptanedionato ligands, and one triphenylphosphine oxide ligand. The coordination geometries of the lanthanide complexes have been evaluated by using single-crystal X-ray analyses and shape-measurement calculations. The complexes are categorized to be seven-coordinate monocapped octahedral structures (point group C-3v). The seven-coordinate lanthanide complexes show high intrinsic emission quantum yields, extra-large radiative rate constants, and unexpected small nonradiative rate constants. The brilliant luminescence properties have been elucidated in terms of the asymmetric coordination geometry and small vibrational quanta related to thermal relaxation

    Four- and Five-Carbon Dicarboxylic Acids Present in Secondary Organic Aerosol Produced from Anthropogenic and Biogenic Volatile Organic Compounds

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    To better understand precursors of dicarboxylic acids in ambient secondary organic aerosol (SOA), we studied C4–C9 dicarboxylic acids present in SOA formed from the oxidation of toluene, naphthalene, α-pinene, and isoprene. C4–C9 dicarboxylic acids present in SOA were analyzed by offline derivatization gas chromatography–mass spectrometry. We revealed that C4 dicarboxylic acids including succinic acid, maleic acid, fumaric acid, malic acid, DL-tartaric acid, and meso-tartaric acid are produced by the photooxidation of toluene. Since meso-tartaric acid barely occurs in nature, it is a potential aerosol tracer of photochemical reaction products. In SOA particles from toluene, we also detected a compound and its isomer with similar mass spectra to methyltartaric acid standard; the compound and the isomer are tentatively identified as 2,3-dihydroxypentanedioic acid isomers. The ratio of detected C4–C5 dicarboxylic acids to total toluene SOA mass had no significant dependence on the initial VOC/NOx condition. Trace levels of maleic acid and fumaric acid were detected during the photooxidation of naphthalene. Malic acid was produced from the oxidation of α-pinene and isoprene. A trace amount of succinic acid was detected in the SOA produced from the oxidation of isoprene

    Four- and Five-Carbon Dicarboxylic Acids Present in Secondary Organic Aerosol Produced from Anthropogenic and Biogenic Volatile Organic Compounds

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    To better understand precursors of dicarboxylic acids in ambient secondary organic aerosol (SOA), we studied C4&ndash;C9 dicarboxylic acids present in SOA formed from the oxidation of toluene, naphthalene, &alpha;-pinene, and isoprene. C4&ndash;C9 dicarboxylic acids present in SOA were analyzed by offline derivatization gas chromatography&ndash;mass spectrometry. We revealed that C4 dicarboxylic acids including succinic acid, maleic acid, fumaric acid, malic acid, DL-tartaric acid, and meso-tartaric acid are produced by the photooxidation of toluene. Since meso-tartaric acid barely occurs in nature, it is a potential aerosol tracer of photochemical reaction products. In SOA particles from toluene, we also detected a compound and its isomer with similar mass spectra to methyltartaric acid standard; the compound and the isomer are tentatively identified as 2,3-dihydroxypentanedioic acid isomers. The ratio of detected C4&ndash;C5 dicarboxylic acids to total toluene SOA mass had no significant dependence on the initial VOC/NOx condition. Trace levels of maleic acid and fumaric acid were detected during the photooxidation of naphthalene. Malic acid was produced from the oxidation of &alpha;-pinene and isoprene. A trace amount of succinic acid was detected in the SOA produced from the oxidation of isoprene
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