Tokyo University of Science

About: Tokyo University of Science is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Catalysis & Thin film. The organization has 15800 authors who have published 24147 publications receiving 438081 citations. The organization is also known as: Tōkyō Rika Daigaku & Science University of Tokyo.

Large nonlinear effect observed in the enantiomeric excess of proline in solution and that in the solid state.

Abstract: How homochiral amino acids and sugars arose out of a presumably prochiral prebiotic environment is a puzzling question, to which many answers have been proposed: for example, absolute asymmetric synthesis with circularly polarized light, photoreactions in chiral crystals, and asymmetric automultiplication with asymmetric autocatalysis, as exemplified by the recent work of Soai et al. There are reports describing a connection between the chirality of amino acids and sugars: Amplification of ee was observed in the aaminoxylation of an aldehyde using proline as catalyst to generate a key intermediate of sugars, while amino acids

The boundary of the meristematic and elongation zones in roots: endoreduplication precedes rapid cell expansion

Abstract: Plant roots consist of a meristematic zone of mitotic cells and an elongation zone of rapidly expanding cells, in which DNA replication often occurs without cell division, a process known as endoreduplication. The duration of the cell cycle and DNA replication, as measured by 5-ethynyl-2′-deoxy-uridine (EdU) incorporation, differed between the two regions (17 h in the meristematic zone, 30 h in the elongation zone). Two distinct subnuclear patterns of EdU signals, whole and speckled, marked nuclei undergoing DNA replication at early and late S phase, respectively. The boundary region between the meristematic and elongation zones was analysed by a combination of DNA replication imaging and optical estimation of the amount of DNA in each nucleus (C-value). We found a boundary cell with 4C nuclei exhibiting the whole pattern of EdU signals. Analyses of cells in the boundary region revealed that endoreduplication precedes rapid cell elongation in roots.