Makiko Nagashima

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Wsc1p is a major cell wall sensor protein localized at the polarized cell surface. The localization of Wsc1p is maintained by endocytosis and recycling from endosomes back to the cell surface, but changes to the vacuole when cells are subjected to heat stress. Exploiting this unique property of Wsc1p, we screened for yeast single-gene deletion mutants(More)
Direct CP violation in B0 --> K+ pi- decay has emerged at the -10% level, but the asymmetry in B+ --> K+ pi0 mode is consistent with zero. This difference points towards possible new physics in the electroweak penguin operator. We point out that a sequential fourth generation, with sizable V(t' s)* V(t' b) and near maximal phase, could be a natural cause.(More)
Within the standard model, a relation involving branching ratios and direct CP asymmetries holds for the B-decay pairs that are related by U-spin. The violation of this relation indicates new physics (NP). In this paper, we assume that the NP affects only the ∆S = 1 decays, and show that the NP operators are generally the same as those appearing in B → πK(More)
We study the effect from a sequential fourth generation quark on penguin-dominated two-body nonleptonic B meson decays in the next-to-leading order perturbative QCD formalism. With an enhancement of the color-suppressed tree amplitude and possibility of a new CP phase in the electroweak penguin amplitude, we can account better for A(CP)(B(0)-->K+(More)
Mass matrices of quarks are studied in the Supersymmetric E6 GUT. After decomposition into SU(5), there are two 5 representations in each generation, which consist of the lepton doublet and the right-handed down-type quarks. It is known that the observed quark and lepton mixing matrices could be reproduced well if an appropriate interchange (twisting)(More)
B → φK (b̄ → s̄) is three separate decays, one for each polarization of the finalstate vector mesons (one longitudinal, two transverse). It is observed that the fraction of transverse decays, fT , and the fraction of longitudinal decays, fL, are roughly equal: fT/fL ≃ 1, in opposition to the naive expectation that fT ≪ fL. If one requires a single(More)
We calculate the contributions of the vector-like quark model to BsBs mixing, taking into account the constraints from the decay B → Xsγ. In this model the neutral bosons mediate flavor-changing interactions at the tree level. However, BsBs mixing is dominated by contributions from the box diagrams with the top quark and the extra up-type quark. In sizable(More)
Abstract CP violation in supersymmetry can give rise to rate asymmetries in the decays of supersymmetric particles. In this work we compute the rate asymmetries for the three-body chargino decays χ̃2 → χ̃1 HH, χ̃2 → χ̃1 ZZ, χ̃2 → χ̃1 W+W− and χ̃2 → χ̃1 ZH. Each of the decays contains contributions mediated by neutral Higgs bosons that can possibly go on(More)
We investigate the leading effects of extending the Standard Model of electroweak interactions by an extra iso-singlet upand downtype quark pair on various distributions and total branching ratio of the inclusive B → Xsll (l = e, μ) rare B decays. The presence of the extra vector-like down quark D results in the non-unitarity of the extended quark mixing(More)