163 research outputs found

    Inversion of normal mode frequencies for estimation of lateral heterogeneity of the earth's elasticity atructure: A numerical test

    Get PDF
    An investigation was made on effect of lateral heterogenity of the earth's elasticity structure on the normal mode frequencies. The lateral heterogeneity is expressed by an expansion of spherical harmonic functions, Pιm(cosθ)sinmΦ and Pιm(cosθ)cosmΦ, up to the second order harmonics (ι≤2). Free oscillation freguencies of the heterogeneous earth were computed by the xyz algorithm. Further we derived an analytic expression of partial derivatives of eigenfrequency with respect to the expansion coefficients, and performed a numerical test to verify whether or not it is possible to estimate the heterogeneity of the earth's structure by the inversion of noemal mode frequencies. When the earth is assumed to be elastically isotropic spheroid with short polar and long equatorial radii, frequency spectra affected by longitudinal heterogeneity terms, Pιm(cosθ)(sinmΦ, cosmΦ) (m≠ 0), for given values of ι and m coincide with each other, because these two terms describe the same heterogeneity when the earth is rotated by π/2m around rotation axis. In such a case, we cannot determine accurately the expansion coefficients of tha two heterogeneity terms by inversion of normal mode frequencies, whereas the coefficients of the latitudinal heterogeneity Pι0(cosθ) can be precisely determined. Therefore it is difficult to estimate of lateral heterogeneity of the earth's elasticity structure by the inversion of normal mode frequencies

    Control of Magnetizing Inrush Current in a Transformer by Means of Thyristors

    Get PDF
    When a transformer is energized, the inrush of abnormally high magnetizing current may be noted for a short time until normal flux conditions are established. This may cause the failure of a protective relay, so many preventives are usually accepted for the purpose of normal relay performance. The authors, instead, now have tried to control the inrush current itself, by means of the soft starting method using two reverse parallel thyristors. In this paper, the method to control the inrush current itself, is presented by the soft-starting method using thyristors. The experimental results of this Method verifies the good controlability of the transient magnetic flux of a transformer and then the availability of the control of magnetizing inrush current in the cases of a single phase connection and a three phase one

    Low atrial septal pacing with dual-chamber pacemakers reduces atrial fibrillation in sick sinus syndrome

    Get PDF
    SummaryBackgroundSick sinus syndrome (SSS) is often complicated with the additional presence of atrial fibrillation (AF). Atrial septal pacing, compared with right atrial appendage (RAA) pacing, shortens the atrial conduction time and reduces the dispersion of the refractoriness. However, low atrial septal (LAS) pacing's efficacy for preventing AF in SSS remains controversial in Japan.Methods and resultsWe analyzed 95 consecutive patients with SSS who underwent dual-chamber pacemaker implantations. Forty-two patients (44%) had a history of AF at the time of the pacemaker implantation. In the group without a history of AF, LAS pacing was performed in 17 patients, and RAA pacing in 36 patients. In the group with a history of AF, LAS pacing was performed in 15 patients, and RAA pacing in 27 patients. We evaluated whether LAS pacing prevented the development of de novo AF and the persistence of AF after pacemaker implantations. No significant differences were found in the baseline characteristics between the RAA and LAS groups regardless of an AF history. During a 1-year follow-up period, in the SSS patients without a history of AF, 19.0% (7/36) of the RAA group developed de novo AF, however, 5.9% (1/17) of the LAS group developed de novo AF (p=0.20). On the other hand, in the SSS patients with a history of AF, 22.0% (6/27) of the RAA group developed persistent AF, but none of the LAS group developed any persistent AF (p=0.049). There were no post-operative complications related to the LAS pacing.ConclusionsLAS pacing is safe and feasible. LAS pacing may prevent the progression to persistent AF in SSS patients with dual-chamber pacemakers

    Novel urinary glycan profiling by lectin array serves as the biomarkers for predicting renal prognosis in patients with IgA nephropathy

    Get PDF
    In IgA nephropathy (IgAN), IgA1 molecules are characterized by galactose deficiency in O-glycans. Here, we investigated the association between urinary glycosylation profile measured by 45 lectins at baseline and renal prognosis in 142 patients with IgAN. The primary outcome was estimated glomerular filtration rate (eGFR) decline (>4 mL/min/1.73 m(2)/year), or eGFR >= 30% decline from baseline, or initiation of renal replacement therapies within 3 years. During follow-up (3.4 years, median), 26 patients reached the renal outcome (Group P), while 116 patients were with good renal outcome (Group G). Multivariate logistic regression analyses revealed that lectin binding signals of Erythrina cristagalli lectin (ECA) (odds ratio [OR] 2.84, 95% confidence interval [CI] 1.11-7.28) and Narcissus pseudonarcissus lectin (NPA) (OR 2.32, 95% CI 1.11-4.85) adjusted by age, sex, eGFR, and urinary protein were significantly associated with the outcome, and they recognize Gal(beta 1-4)GlcNAc and high-mannose including Man(alpha 1-6)Man, respectively. The addition of two lectin-binding glycan signals to the interstitial fibrosis/tubular atrophy score further improved the model fitness (Akaike's information criterion) and incremental predictive abilities (c-index, net reclassification improvement, and integrated discrimination improvement). Urinary N-glycan profiling by lectin array is useful in the prediction of IgAN prognosis, since ECA and NPA recognize the intermediate glycans during N-glycosylation of various glycoproteins

    ICBT survey for cervical cancer

    Get PDF
    To review the current status of, and labor expended for (in terms of time required), intracavitary brachytherapy (ICBT) in definitive radiotherapy/chemoradiotherapy for cervical cancer patients, two national surveys were performed. The first survey was conducted between July and August 2016 and consisted of a questionnaire of 12 items regarding ICBT procedures for cervical cancer, which was sent to 173 centers installed with high-dose-rate remote after-loading brachytherapy systems. Between November and December 2016, another survey was performed in 79 centers to evaluate labor required for ICBT procedures in terms of time spent and number of staff involved. In the first survey, the response rate was 77% of the 173 centers. ICBT was performed for cervical cancer in 118 (89%) centers. Imaging modalities used after applicator insertion were X-ray alone in 46 (40%), computed tomography in 69 (60%) and magnetic resonance imaging in 5 (4%) centers. Three-dimensional (3D) planning was performed in 55 centers (48%). Fifty-five (70%) centers responded to the second survey regarding ICBT-mandated labor. The median cumulative duration of the entire ICBT procedure was 330 min (the sum of the times spent by each staff member) and was longer in the 3D image–guided brachytherapy (3D-IGBT) (405 min) than in the X-ray group (230 min). This trend was significant for the specific processes of image acquisition and treatment planning, especially for radiation oncologists. In definitive radiotherapy/chemoradiotherapy for cervical cancer patients, 3D-IGBT use has been gradually spreading in Japan. The present survey revealed that ICBT, especially 3D-IGBT, requires substantial labor and time from staff

    Late-onset renal variant Fabry disease with R112H mutation and mild increase in plasma globotriaosylsphingosine: a case report

    Get PDF
    Fabry disease (FD) is an X-linked disorder resulting in a deficiency of α-galactosidase A (GLA) activity. The R112H mutation of GLA is relatively common in Japanese FD patients, characterized by a late-onset phenotype, almost normal to mild lyso-Gb3 elevation, and mild clinical symptoms, despite low GLA activity. This is due to the structural features of the R112H GLA protein. We herein report the case of a 42-year-old male patient with late-onset FD with a R112H mutation. The patient exhibited only renal involvement with no other organ damage and was successfully treated with galactosidase beta and subsequent migalastat for approximately 10 years. Especially, migalastat was clinically effective in normalizing plasma lyso-Gb3 levels and inhibiting the progression of renal damage associated with FD. Therefore, the use of migalastat in the FD patients with R112H mutation is highly recommended based on this case report

    State- and water repellency-controllable molecular glass of pillar[5]arenes with fluoroalkyl groups by guest vapors

    Get PDF
    Molecular glasses are low-molecular-weight organic compounds that are stable in the amorphous state at room temperature. Herein, we report a state- and water repellency-controllable molecular glass by n-alkane guest vapors. We observed that a macrocyclic host compound pillar[5]arene with the C₂F₅ fluoroalkyl groups changes from the crystalline to the amorphous state (molecular glass) by heating above its melting point and then cooling to room temperature. The pillar[5]arene molecular glass shows reversible transitions between amorphous and crystalline states by uptake and release of the n-alkane guest vapors, respectively. Furthermore, the n-alkane guest vapor-induced reversible changes in the water contact angle were also observed: water contact angles increased and then reverted back to the original state by the uptake and release of the n-alkane guest vapors, respectively, along with the changes in the chemical structure and roughness on the surface of the molecular glass. The water repellency of the molecular glass could be controlled by tuning the uptake ratio of the n-alkane guest vapor
    corecore