Lattice study on QCD-like theory with exact center symmetry

We investigate QCD-like theory with exact center symmetry, with emphasis on the finite-temperature phase transition concerning center and chiral symmetries. On the lattice, we formulate center symmetric $SU(3)$ gauge theory with three fundamental Wilson quarks by twisting quark boundary conditions in a compact direction ($Z_3$-QCD model). We calculate the expectation value of Polyakov loop and the chiral condensate as a function of temperature on 16^3 x 4 and 20^3 x 4 lattices along the line of constant physics realizing $m_{PS}/m_{V}=0.70$. We find out the first-order center phase transition, where the hysteresis of the magnitude of Polyakov loop exists depending on thermalization processes. We show that chiral condensate decreases around the critical temperature in a similar way to that of the standard three-flavor QCD, as it has the hysteresis in the same range as that of Polyakov loop. We also show that the flavor symmetry breaking due to the twisted boundary condition gets qualitatively manifest in the high-temperature phase. These results are consistent with the predictions based on the chiral effective model in the literature. Our approach could provide novel insights to the nonperturbative connection between the center and chiral properties.Comment: 25 pages, 6 figures, to apper in JHE

Lattice study on QCD-like theory with exact center symmetry

We investigate QCD-like theory with exact center symmetry, with emphasis on the finite-temperature phase transition concerning center and chiral symmetries. On the lattice, we formulate center symmetric $SU(3)$ gauge theory with three fundamental Wilson quarks by twisting quark boundary conditions in a compact direction ($Z_3$-QCD model). We calculate the expectation value of Polyakov loop and the chiral condensate as a function of temperature on 16^3 x 4 and 20^3 x 4 lattices along the line of constant physics realizing $m_{PS}/m_{V}=0.70$. We find out the first-order center phase transition, where the hysteresis of the magnitude of Polyakov loop exists depending on thermalization processes. We show that chiral condensate decreases around the critical temperature in a similar way to that of the standard three-flavor QCD, as it has the hysteresis in the same range as that of Polyakov loop. We also show that the flavor symmetry breaking due to the twisted boundary condition gets qualitatively manifest in the high-temperature phase. These results are consistent with the predictions based on the chiral effective model in the literature. Our approach could provide novel insights to the nonperturbative connection between the center and chiral properties.Comment: 25 pages, 6 figures, to apper in JHE

Leukocytapheresis Therapy Improved Cholestasis in a Patient Suffering from Primary Sclerosing Cholangitis with Ulcerative Colitis

Primary sclerosing cholangitis (PSC) is an autoimmune disease of the hepatobiliary system for which effective therapy has not been established. Leukocytapheresis (LCAP) therapy is known to effective in patients with ulcerative colitis (UC). In addition, effects of LCAP therapy were reported on some autoimmune diseases such as Crohn's disease, rheumatoid arthritis and rapidly progressive glomerulonephritis. Here we report the case of a 29-year-old man with PSC associated with UC who was treated with LCAP therapy. He had a 16-year history of UC and a 12-year history of PSC. Although he was under treatment with prednisolone and ursodeoxycholic acid, exacerbation of UC and PSC-associated cholestasis were seen. Since he showed side effects of prednisolone, he was treated with LCAP. Not only improvement of UC, but also decreased serum alkaline phosphatase, γ-guanosine triphosphate and total bile acids, suggesting improvement of PSC-associated cholestaisis, were seen after treatment with LCAP. Our experience with this case suggests that LCAP therapy could be a new effective therapeutic strategy for patients with PSC associated with UC

横断的・総合的な幼稚園教育教員養成プログラムの構築研究

本研究では，別冊『－平成30年度広島大学大学院教育学研究科共同研究プロジェクト－横断的・総合的な幼稚園教育教員養成プログラムの構築研究論文集』を作成し，紙幅の都合で本報告書に掲載できなかった調査・研究の成果を掲載した