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Rikkyo University , also known as Saint Paul's University, is a private university, located in Ikebukuro, Tokyo.A leading liberal arts teaching and research institution, Rikkyo is the largest Anglican Christian affiliated university in Japan and is a member of the "Big Six" grouping of prominent private universities in Tokyo. The university is known for its supportive and student focused approach to academic study; encouraging all enrolled students to challenge themselves and discover their own innate potential in their chosen field of study. A philosophy symbolized by the motto "academy of freedom" ; urging students to reject preconceived limitations and to broaden their knowledge and appreciation of the essence of all things through advanced study. Wikipedia.

Irie M.,Rikkyo University | Fukaminato T.,Hokkaido University | Matsuda K.,Kyoto University | Kobatake S.,Osaka City University
Chemical Reviews | Year: 2014

Chemical bond rearrangement during the phototransformation induces electronic as well as geometrical structure changes of the molecules. The molecular structure changes can be applied to various photonic devices. The electronic structure changes can be applied to optical memory media and various photoswitching devices. On the other hand, the geometrical structure changes can be applied to light-driven actuators and others. The photochromic diarylethene was serendipitously discovered during the course of study on photoresponsive polymers a quarter of a century ago. Various types of polymers having photoisomerizable chromophores, such as spiropyran, azobenzene, or stilbene, in the side or main chains, have been prepared in an attempt to change their conformation by photoirradiation.

Individuals of many avian and mammalian species produce antipredator calls when they encounter a predator. These calls often vary in acoustic structure depending on the type or level of predation risk, thereby eliciting the appropriate escape responses in conspecifics. Such complexity in communication may also be advantageous in situations in which animals recruit other individuals to mob predators because different risks may sometimes require different mobbing responses. I tested this idea in Japanese great tits, Parus major minor, which produce acoustically distinct mobbing calls for two different nest predators: 'chicka' calls for jungle crows, Corvus macrorhynchos, and 'jar' calls for Japanese rat snakes, Elaphe climacophora. A playback experiment revealed that adult great tits responded to different mobbing calls with qualitatively different behaviours: they scanned the horizon in response to 'chicka' calls and gazed towards the ground in response to 'jar' calls. These two responses help adults search for and detect the corresponding predators since crows fly to the nest and snakes approach from the ground. This study demonstrates that the mobbing calls of Japanese great tits transmit referential information about predator types and elicit the appropriate predator-searching behaviours in adults. © 2012 The Association for the Study of Animal Behaviour.

Takahashi D.,Rikkyo University
Journal of High Energy Physics | Year: 2011

We construct a boundary state for a class of analytic solutions in the Witten's open string field theory. The result is consistent with the property of the zero limit of a propagator's length, which was claimed in [19]. And we show that our boundary state becomes expected one for the perturbative vacuum solution and the tachyon vacuum solution. We also comment on possible presence of multi-brane solutions and ghost brane solutions from our boundary state. © 2011 SISSA.

Horiguchi G.,Rikkyo University | Tsukaya H.,University of Tokyo
Frontiers in Plant Science | Year: 2014

The regulation of organ size in higher organisms is a fundamental issue in developmental biology. In flowering plants, a phenomenon called "compensation" has been observed where a cell proliferation defect in developing leaf primordia triggers excessive cell expansion. As a result, final leaf size is not significantly reduced compared to that expected from the reduction in leaf cell numbers. Recent genetic studies have revealed several key features of the compensation phenomenon. Compensation is induced either cell autonomously or non-cell autonomously depending on the trigger that impairs cell proliferation; a certain type of compensation is induced only when cell proliferation is impaired beyond a threshold level. Excessive cell expansion is achieved by either an increased cell expansion rate or a prolonged period of cell expansion via genetic pathways that are also required for normal cell expansion. These results indicate that cell proliferation and cell expansion are coordinated through multiple pathways during leaf size determination. Further classification of compensation pathways and their characterization at the molecular level will provide a deeper understanding of organ size regulation. © 2011 Horiguchi and Tsukaya.

Kimura T.,Rikkyo University | Sasaki S.,Kitasato University
Nuclear Physics B | Year: 2013

We study an N=(4,4) supersymmetric gauged linear sigma model which gives rise to the nonlinear sigma model for multi-centered KK-monopoles. We find a new T-duality transformation of the model even in the presence of F-terms. Performing T-duality, we find the gauged linear sigma model whose IR limit describes the exotic 522-brane with B-field. © 2013 Elsevier B.V.

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