49 research outputs found

    Buddhist Manuscript Cultures in Premodern Japan

    Get PDF
    Recent discoveries and scholarship on Japanese Buddhist manuscripts have illuminated new areas of research and raised previously unexplored questions in Buddhist studies and East Asian religions. This article introduces some of the recent finds and approaches to these materials. It focuses on three sets of sources: scriptorium documents from an imperial treasure house known as the Shōsōin, canonical manuscripts (issaikyō) based on texts translated or composed in China, and sacred works (shōgyō) produced and collected by Japanese monks for use in temple life. In addition to surveying these sources and the most influential secondary literature on them, this article proposes methodological alternatives to philological studies by focusing on what I call ritual, curricular, social, and material approaches

    Coexistence of Förster and Dexter Energy Transfer Pathways from an Antenna Ligand to Lanthanide Ion in Trivalent Europium Complexes through Phosphine-Oxide Bridges

    No full text
    Trivalent europium (Eu3+) complexes are attractive materials for luminescence applications if energy transfer from antenna ligands to the lanthanide ion is efficient. However, the microscopic mechanisms of the transfer remain elusive and fundamental physical chemistry questions still require answers. We track the energy transfer processes in a luminescent complex Eu(hfa)3(DPPTO)2 (hfa: hexafluoroacetylacetonate, DPPTO: 2-diphenylphosphoryltriphenylene) using time-resolved photoluminescence spectroscopy. In addition to the conventional Dexter-type energy transfer pathway through the T1 state of the ligands, we discovered the Forster energy transfer pathway from the S1 of the DPPTO ligands to the 5D1 state of Eu3+ through the weak electronic interaction of a phosphine-oxide bridge. The short timescale of the energy transfer (16 ns, 127 ns) results in its high quantum yield. The coexistence of the distinct energy transfer pathways from a single chromophore is important for establishing design strategies of luminescent complexes. <br /

    Coordination Geometrical Effect on Ligand-to-Metal Charge Transfer-Dependent Energy Transfer Processes of Luminescent Eu(III) Complexes

    Get PDF
    Photophysical properties of europium (Eu(III)) complexes are affected by ligand-to-metal charge transfer (LMCT) states. Two luminescent Eu(III) complexes with three tetramethylheptadionates (tmh) and pyridine (py), [Eu(tmh)(3)(py)(1)] (seven-coordinated monocapped-octahedral structure) and [Eu(tmh)(3)(py)(2)] (eight-coordinated square antiprismatic structure), were synthesized for geometrical-induced LMCT level control. Distances between Eu(III) and oxygen atoms of tmh ligands were estimated using single-crystal X-ray analyses. The contribution percentages of pi-4f mixing in HOMO and LUMO at the optimized structure in the ground state were calculated using DFT (LC-BLYP). The Eu-O distances and their pi-4f mixed orbitals affect the energy level of LMCT states in Eu(III) complexes. The LMCT energy level of an eight-coordinated Eu(III) complex was higher than that of a seven-coordinated Eu(III) complex. The energy transfer processes between LMCT and Eu(III) ion were investigated using temperature-dependent and time-resolved emission lifetime measurements of D-5(0) -> F-7(J) transitions of Eu(III) ions. In this study, the LMCT-dependent energy transfer processes of seven- and eight-coordinated Eu(III) complexes are demonstrated for the first time

    Protein-N-myristoylation-dependent phosphorylation of serine 13 of tyrosine kinase Lyn by casein kinase 1γ at the Golgi during intracellular protein traffic

    Get PDF
    Protein N-myristoylation of Src-family kinases (SFKs) is a critical co-translational modification to anchor the enzymes in the plasma membrane. Phosphorylation of SFKs is also an essential modification for regulating their enzymatic activities. In this study, we used Phos-tag SDS-PAGE to investigate N-myristoylation-dependent phosphorylation of SFKs and their non-N-myristoylated G2A mutants. The serine-13 residue of Lyn (Lyn-S13) was shown to be N-myristoylation-dependently phosphorylated. Although there have been more than 40 reports of mass spectrometric studies on phosphorylation at Lyn-S13, the kinase responsible remained unclear. We succeeded in identifying casein kinase 1γ (CK1γ) as the kinase responsible for phosphorylation of Lyn-S13. In HEK293 cells co-expressing Lyn and CK1γ, the phosphorylation level of Lyn-S13 increased significantly. CK1γ is unique among the CK1 family (α, γ, δ, and ε) in carrying an S-palmitoylation site for membrane binding. Co-expression with the non-S-palmitoylated CK1γ mutant, which localized in the cytosol, gave no increase in the phosphorylation level at Lyn-S13. In HEK293 cells expressing the non-S-palmitoylated Lyn-C3A mutant, on the other hand, the Lyn-C3A mutant was phosphorylated at Lyn-S13, and the mutant remained at the Golgi. These results showed that S-palmitoylated CK1γ can phosphorylate S13 of N-myristoylated Lyn at the Golgi during intracellular protein traffic.This work was supported in part by KAKENHI Grants 18K065960 to E.K.-K., 19K071470 to E.K., and 17K08237 to T.K., and by a research grant from Chugoku Regional Innovation Research Center to E.K
    corecore