University of Tokyo

About: University of Tokyo is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Population & Gene. The organization has 134564 authors who have published 337567 publications receiving 10178620 citations. The organization is also known as: Todai & Universitas Tociensis.

Visible-light-response and photocatalytic activities of TiO2 and SrTiO3 photocatalysts codoped with antimony and chromium

Abstract: TiO2 and SrTiO3 codoped with antimony and chromium showed intense absorption bands in the visible light region and possessed 2.2 and 2.4 eV of energy gaps, respectively. TiO2 codoped with antimony and chromium evolved O2 from an aqueous silver nitrate solution under visible light irradiation, while SrTiO3 codoped with antimony and chromium evolved H2 from an aqueous methanol solution. The activity of TiO2 photocatalyst codoped with antimony and chromium was remarkably higher than that of TiO2 doped with only chromium. It was due to that the charge balance was kept by codoping of Sb5+ and Cr3+ ions, resulting in the suppression of formation of Cr6+ ions and oxygen defects in the lattice which should work as effectively nonradiative recombination centers between photogenerated electrons and holes.

A √N algorithm for mutual exclusion in decentralized systems

Abstract: An algorithm is presented that uses only c√N messages to create mutual exclusion in a computernetwork, where N is the number of nodes and c a constant between 3 and 5. The algorithm issymmetric and allows fully parallel operation.

Novel Optical Trap of Atoms with a Doughnut Beam

Abstract: We have constructed a novel optical trap for neutral atoms by using a Laguerre-Gaussian (doughnut) beam whose frequency is blue detuned to the atomic transition. Laser-cooled rubidium atoms are trapped in the dark core of the doughnut beam with the help of two additional laser beams which limit the atomic motion along the optical axis. About ${10}^{8}$ atoms are initially loaded into the trap, and the lifetime is 150 ms. Because the atoms are confined at a point in a weak radiation field in the absence of any external field, ideal circumstances are provided for precision measurements. The trap opens the way to a simple technique for atom manipulation, including Bose-Einstein condensation of gaseous atoms.

One thousand fifty-six hepatectomies without mortality in 8 years.

Abstract: Background Despite improvements in diagnostic and surgical techniques, operative mortality associated with liver resection is still greater than 2% in most of the recent studies. Hypothesis By refining preoperative and postoperative care and surgical skills, liver resection mortality can be decreased to zero. Design Retrospective cohort study to analyze postoperative morbidity and mortality in 1056 consecutive hepatectomies performed at a single medical center during 8 years. Setting Tertiary referral center. Patients A total of 915 patients who underwent 1056 consecutive hepatic resections: 532 for hepatocellular carcinoma, 262 for other primary and secondary liver malignancies, 57 for biliary tract malignancy, 174 for living donor liver transplantation, and 31 for other benign diseases. Main Outcome Measures Operative mortality and morbidity rates. Results No operative mortality occurred. Major complications, as defined by postoperative radiologic or surgical intervention, occurred in 3% of patients with hepatocellular carcinoma, 8% with other liver malignancy, 28% with biliary malignancy, and 5% of living donor liver transplantation donors. Using multiple logistic regression, independent risk factors associated with major complications were operative blood loss of 1000 mL or greater for hepatocellular carcinoma and total bilirubin level of 1.0 mg/dL or greater (≥17 µmol/L) and operative time greater than 6 hours for other liver malignancy. No independent factors associated with major complications were identified for biliary malignancy or for living donor liver transplantation donors among the variables investigated in this study. Conclusions Liver resection can be performed without mortality provided that it is carried out in a high-volume medical center by well-trained hepatobiliary surgeons paying meticulous attention to the balance between the liver functional reserve and the volume of liver to be removed.

Improved Gateway binary vectors: high-performance vectors for creation of fusion constructs in transgenic analysis of plants.

Abstract: We made a series of improved Gateway binary vectors (pGWBs) for plant transformation. Fifteen different reporters and tags, sGFP, GUS, LUC, EYFP, ECFP, G3GFP, mRFP, 6xHis, FLAG, 3xHA, 4xMyc, 10xMyc, GST, T7, and TAP, were employed. Some vectors carry the 2x35S-Omega promoter for higher-level expression. The kanamycin- and hygromycin-resistant markers are independently available for each of the 43 types of vectors, thus an additional transformation of once-transformed plants can be carried out easily. Their small size and high-copy number in Escherichia coli make possible easier handling at plasmid preparation and sequencing. Improved pGWBs should be a powerful tool for transgenic research in plants.