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: Thin film & Enantioselective synthesis. 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.

Photocatalytic O2 evolution of rhodium and antimony-codoped rutile-type TiO2 under visible light irradiation

Abstract: The effects upon the photophysical and photocatalytic properties of the codoping of rhodium and antimony in rutile-type TiO2 were investigated. TiO2 codoped with rhodium and antimony (TiO2:Rh/Sb) had an absorption band in the visible light region. Its energy gap was 2.1 eV. The TiO2:Rh/Sb powder showed photocatalytic activity for the oxidation of water to form O2 in the presence of Ag+ ions as an electron acceptor under visible light irradiation (λ > 440 nm), whereas TiO2 doped with only rhodium showed no activity. The photocatalytic activity strongly depended on the amount and ratio of the Sb/Rh dopant. Electron spin resonance, diffuse reflection spectroscopy, and X-ray absorption near-edge structure analyses revealed that the doped rhodium exists in a trivalent oxidation state in the active photocatalyst. The photocatalytic activity was decreased remarkably even by a small amount of Rh4+ ions. Antimony played an important role in suppressing the formation of Rh4+ ions by charge compensation. Thus, it ha...

Telescope Array Experiment

Abstract: The TA observatory is a hybrid detector system consisting of both a surface detector array as well as a set of fluorescence detectors. The observatory will measure the energy spectrum, anisotropy and composition of ultra-high energy cosmic rays. The surface detectors are being deployed and the array should be complete by the end of February, 2007. We will soon be collecting hybrid data at the Telecope Array.

Silver ion induces a cyclosporine a-insensitive permeability transition in rat liver mitochondria and release of apoptogenic cytochrome C.

Abstract: Various reagents are known to open the mitochondrial permeability pore (PTP) and induce a permeability transition (PT), releasing apoptogenic proteins from the inter-membrane space and triggering apoptosis. In this study,we examined the effect of Ag + , a known cytotoxic sulfhydryl-reactive heavy metal, on isolated rat liver mitochondria. The following results were obtained: (1) Upon addition, Ag + instantly induced mitochondrial swelling and acceleration of respiration. (2) Cyclosporine A, a specific inhibitor of classical PT, was ineffective against the effect of Ag + , indicating that silver ions induced non-classic PT. (3) Sulfhydryl reagents such as reduced glutathione completely inhibited the effects of Ag + on the mitochondria. (4) Experimental results using polyethylene glycol indicated that Ag + induced opening of a pore in the inner mitochondrial membrane, which could be PTP of another open state or a distinct pore. (5) Electron microscopic analysis of mitochondria treated with Ag + showed a novel mitochondrial configuration that was apparently different from that of normal mitochondria or Ca 2 + -treated mitochondria. (6) Ag + also induced the release of apoptogenic cytochrome c in a CsA-insensitive but GSH-sensitive manner. These results suggest that Ag + promotes a nonclassical permeability increase in the mitochondrial inner membrane that is clearly distinguishable from the classical PT and releases apoptogenic cytochrome c in a classical PT-independent manner.

The ASTRO-H X-ray observatory

Abstract: The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions initiated by the Institute of Space and Astronautical Science (ISAS). ASTRO-H will investigate the physics of the highenergy universe via a suite of four instruments, covering a very wide energy range, from 0.3 keV to 600 keV. These instruments include a high-resolution, high-throughput spectrometer sensitive over 0.3–12 keV with high spectral resolution of ΔE ≦ 7 eV, enabled by a micro-calorimeter array located in the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers covering 5–80 keV, located in the focal plane of multilayer-coated, focusing hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4–12 keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the 40–600 keV band. The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes.