595 research outputs found

    On relative tt-designs in polynomial association schemes

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    Motivated by the similarities between the theory of spherical tt-designs and that of tt-designs in QQ-polynomial association schemes, we study two versions of relative tt-designs, the counterparts of Euclidean tt-designs for PP- and/or QQ-polynomial association schemes. We develop the theory based on the Terwilliger algebra, which is a noncommutative associative semisimple C\mathbb{C}-algebra associated with each vertex of an association scheme. We compute explicitly the Fisher type lower bounds on the sizes of relative tt-designs, assuming that certain irreducible modules behave nicely. The two versions of relative tt-designs turn out to be equivalent in the case of the Hamming schemes. From this point of view, we establish a new algebraic characterization of the Hamming schemes.Comment: 17 page

    Analytic Solutions of Teukolsky Equation in Kerr-de Sitter and Kerr-Newman-de Sitter Geometries

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    The analytic solution of Teukolsky equation in Kerr-de Sitter and Kerr-Newman-de Sitter geometries is presented and the properties of the solution are examined. In particular, we show that our solution satisfies the Teukolsky-Starobinsky identities explicitly and fix the relative normalization between solutions with the spin weight ss and s-s.Comment: 24 pages, LaTe

    Studies of the efficacy and safety of methotrexate at dosages over 8 mg/week using the IORRA cohort database

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    The maximum dosage of methotrexate (MTX) for treatment of rheumatoid arthritis (RA) formally approved in Japan is 8 mg/week. We intended to examine the efficacy and safety of MTX at dosages over 8 mg/week in Japanese rheumatoid arthritis patients using the large Institute of Rheumatology, Rheumatoid Arthritis (IORRA) cohort database. Among 9,122 patients registered in the IORRA database from the October 2000 survey to the October 2007 survey, 5,201 patients who had been treated with MTX were selected. We attempted to overcome the drawbacks innate to nonrandomized studies by using longitudinal analyses and multifactorial logistic regression analyses. Cross-sectional analysis of data obtained from the October 2007 survey indicated that dosages of MTX higher than 8 mg/week were used in 27.5% of patients treated with MTX. Longitudinal analyses based on data from three consecutive phases showed that final Disease Activity Score-28 (DAS28) values were significantly lower [n = 260, mean difference 0.563, 95% confidence interval (CI) 0.438–0.688, P < 2.2 × 10−22, two-sided paired t test] than initial values when MTX was increased from 8 mg/week or lower to over 8 mg/week. In addition, longitudinal analyses based on data from two consecutive phases indicated decreases in DAS28 values of 0.26 ± 1.04 (n = 690, P = 6.78 × 10−11, two-sided paired t test) when MTX dosages were increased from 8 mg/week or lower to over 8 mg/week, compared with decreases of 0.07 ± 0.89 (n = 2,125, P = 0.000307) when the dosage was maintained at 8 mg/week. The decreases in DAS28 values were significantly larger in the former than the latter (P = 2.27 × 10−6, two-sided unpaired t test). Concerning safety of MTX at dosages over 8 mg/week, we performed logistic regression analysis in which the objective variable was the existence or nonexistence of self-reported side-effects and the explanatory variable was the MTX dosage in the former phase, with adjustments made for age, sex, body mass index (BMI), steroid administration, folic acid administration, concomitant pulmonary diseases, and renal dysfunction. The results indicated that MTX dosages over 8 mg/week did not have any association with either severe or severe + moderate side-effects. These data regarding both efficacy and safety of MTX at dosages over 8 mg/week in Japanese RA patients would provide the basis for use of the drug at dosages currently not formally approved by the Japanese government

    Changes in Knowledge Levels through Lectures on Radiotherapy to Nursing Students in Japan

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    Background:Recently, the number of patients choosing radiotherapy is increasing in Japan. It is necessary for even nurses to have knowledge of radiotherapy. We measured the degree of awareness with a lecture on how a nursing student can obtain knowledge of radiotherapy.Materials and methods: Forty nursing students who were in their third year and preparing for their national nursing certification in two months were recruited. The 90-min lecture covered a range of topics from general theories to specific concepts. The students were not informed that they would be required to fill a survey at the end of the lecture. This was to avoid bias that could occur from knowing in advance that a survey would be conducted.Results: The following items below were particularly remarkable. The distinction between the radiologist and the radiation oncologist. The radiotherapy is a local therapy. The pain from bone metastasis could be relieved.Conclusion: Students had very little knowledge on radiotherapy before the lecture. the results of this study indicated the need to increase the number of lectures on radiotherapy for nursing as well medical students. As the number of radiotherapy patients increases

    Asymmetric reductive cyclization using the intramolecular conjugate addition of enolates onto α,β-unsaturated sulfoxides

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    Li(sec-Bu)3BH-mediated reductive cyclization of optically pure 8-((S)-p-tolylsulfinyl)-(2E,7Z)-octadienoate 9 and 7-(p-tolylsulfinyl)-2,6-heptadienoate 16 afforded trans-2-((p-tolylsulfinyl)-methyl)cyclohexane-1-carboxylate and trans-2-((p-tolylsulfinyl)methyl)cyclopentane-1-carboxylate, respectively, as a single isomer

    Preparatory acoustic emission activity of hydraulic fracture in granite with various viscous fluids revealed by deep learning technique

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    To investigate the influence of fluid viscosity on the fracturing process, we conducted hydraulic fracturing experiments on Kurokami-jima granite specimens with resins of various viscosities. We monitored the acoustic emission (AE) activity during fracturing and estimated the moment tensor (MT) solutions for 54 727 AE events using a deep learning technique. We observed the breakdown at 14–22 MPa of borehole pressure, which was dependent on the viscosity, as well as two preparatory phases accompanying the expansion of AE-active regions. The first expansion phase typically began at 10–30 per cent of the breakdown pressure, where AEs occurred three-dimensionally surrounding the wellbore and their active region expanded with time towards the external boundaries of the specimen. The MT solutions of these AEs corresponded to crack-opening (tensile) events in various orientations. The second expansion phase began at 90–99 per cent of the breakdown pressure. During this phase, a new planar AE distribution emerged from the borehole and expanded along the maximum compression axis, and the focal mechanisms of these AEs corresponded to the tensile events on the AE-delineating plane. We interpreted that the first phase was induced by fluid penetration into pre-existing microcracks, such as grain boundaries, and the second phase corresponded to the main fracture formation. Significant dependences on fluid viscosity were observed in the borehole pressure at the time of main fracture initiation and in the speed of the fracture propagation in the second phase. The AE activity observed in the present study was fairly complex compared to that observed in previous experiments conducted on tight shale samples. This difference indicates the importance of the interaction between the fracturing fluid and pre-existing microcracks in the fracturing process

    The combination of polymorphisms within interferon-γ receptor 1 and receptor 2 associated with the risk of systemic lupus erythematosus

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    AbstractGenetic factors seem to play a significant role in susceptibility to systemic lupus erythematosus (SLE). We previously described the amino acid polymorphism (Val14Met) within the IFN-γ receptor 1 (IFN-γR1), and that the frequency of the Met14 allele in SLE patients was significantly higher than that of the healthy control population [Tanaka et al. (1999) Immunogenetics 49, 266–271]. We also found an amino acid polymorphism (Gln64Arg) within IFN-γ receptor 2 (IFN-γR2). Since the IFN-γ receptor is a complex consisting of IFN-γR1 and IFN-γR2, we searched for the particular combination of two kinds of amino acid polymorphisms found within the IFN-γ receptor which plays a prominent role in susceptibility to SLE. The greatest risk of the development of SLE was detected in the individuals who had the combination of IFNGR1 Met14/Val14 genotype and IFNGR2 Gln64/Gln64 genotype
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