Y. Sakamura

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We provide a systematic and practical method of deriving 5D supergravity action described by 4D superfields on a general warped geometry, including a non-BPS background. Our method is based on the superconformal formulation of 5D supergravity, but is easy to handle thanks to the superfield formalism. We identify the radion superfield in the language of 5D(More)
We discuss the dimensional reduction of five-dimensional supergravity com-pactified on S 1 /Z 2 keeping the N = 1 off-shell structure. Especially we clarify the roles of the Z 2-odd N = 1 multiplets in such an off-shell dimensional reduction. Their equations of motion provide constraints on the Z 2-even mul-tiplets and extract the zero modes from the(More)
It is not clear to what extent poor insight is inherent in schizophrenic psychopathology or is related to clinical factors. It is clinically important to elucidate this point to know how some insight remains intact in schizophrenia. Sixty-three ICD-10 schizophrenics were recruited. Insight was measured by David's three-dimensional scale, which deals with(More)
A simple mechanism for SUSY breaking is proposed due to the coexistence of BPS domain walls. It requires no messenger fields nor complicated SUSY breaking sector on any of the walls. We assumed that our world is on a BPS domain wall and that the other BPS wall breaks the SUSY preserved by our wall. We obtain an N = 1 model in four dimensions which admits an(More)
Clinically available camptothecins (CPTs), such as irinotecan (CPT-11) and topotecan, represent one of the most promising classes of antitumor agents, despite their toxicity. To improve their pharmacological profiles, a new macromolecular prodrug, denoted T-0128, was synthesized. This prodrug is a novel CPT analogue (T-2513)-carboxymethyl (CM) dextran(More)
A SUSY breaking mechanism with no messenger fields is proposed. We assume that our world is on a domain wall and SUSY is broken only by the coexistence of another wall with some distance from our wall. We find an N = 1 model in four dimensions which admits an exact solution of a stable non-BPS configuration of two walls and studied its properties(More)
We derive 5D N = 1 superspace action including the radion superfield. The radion is treated as a dynamical field and identified as a solution of the equation of motion even in the presence of the radius stabilization mechanism. Our derivation is systematic and based on the superconformal formulation of 5D supergravity. We can read off the couplings of the(More)
SUSY breaking without messenger fields is proposed. We assume that our world is on a wall and SUSY is broken only by the coexistence of another wall with some distance from our wall. The Nambu-Goldstone fermion is localized on the distant wall. Its overlap with the wave functions of physical fields on our wall gives the mass splitting of physical fields on(More)
A possibility that the origin of the CP violation in our world is a domain wall itself, on which we are living, is investigated in the context of the brane world scenario. We estimate the amount of the CP violation on our wall, and show that either of order one or suppressed CP phases can be realized. An interesting case where CP is violated due to the(More)