Tokyo University of Technology
Tokyo, Japan

Tokyo University of Technology is a private university in Hachiōji, Tokyo, Japan. The predecessor of the school was founded in May 1947. After becoming a vocational school in 1953, it was chartered as a university in 1986. Wikipedia.

Time filter
Source Type

Nishio K.,Tokyo University of Technology
Electrochemistry Communications | Year: 2017

An Au thin film, which was sputter-deposited on an Al substrate, was potentiostatically anodized in oxalic acid. The Au film was first anodized and a spongelike nanoporous film grew down to the interface between Au and Al. Then, the Al was anodized and a very thin and fine nanoporous alumina film was formed underneath the nanoporous Au. Under the same anodization conditions, the current density for Al was ~ 40 μA cm− 2, less than 1% of that for Au (~ 30 mA cm− 2). The growth rates of the nanoporous films were ~ 0.7 nm/min for Al and 26 nm/min for Au, indicating that the growth rate of nanoporous alumina was less than 3% of that of nanoporous Au. Al is suitable as the substrate for preparing nanoporous Au films because the electrochemical reactions of both the electrolyte and the substrate are significantly suppressed when the nanopores penetrate Au and the electrolyte reaches the substrate. © 2017 Elsevier B.V.

Yoshida N.,Tokyo University of Technology
Archives of dermatological research | Year: 2012

To examine factors that regulate ceramide production during keratinization of the human stratum corneum (SC), we developed a reconstructed human epidermal keratinization model in which a fresh layer of SC is newly formed within 1 week. Addition of the UDP-glucose: ceramide glucosyltransferase inhibitor 1-phenyl-2-decanoylamino-3-morpholino-1-propanol significantly diminished SC ceramide levels (expressed as μg/mg protein) with decreased glucosylceramide levels. Desipramine hydrochloride, an inhibitor of sphingomyelinase, also significantly reduced SC ceramide levels. Similarly, conduritol B epoxide, an inhibitor of β-glucocerebrosidase, significantly down-regulated SC ceramide levels and significantly increased glucosylceramide levels. These results indicate the reliability of this model to elucidate ceramide synthesis regulating factors. Using this model, we assessed the effects of the inflammatory cytokine interleukin-1α (IL-1α), several bioactive sphingolipids and all-trans retinoic acid (RA) on ceramide levels in the SC. Whereas treatment with IL-1α (at 10 nM) significantly down-regulated ceramide levels, treatment with sphingosylphosphorylcholine (at 50 μM) or sphingosine-1-phosphate (at 10 or 20 μM) distinctly up-regulated ceramide levels. Interestingly, RA (at low as 10 nM) significantly up-regulated ceramide levels without affecting the formation of the SC or levels of keratinization-related proteins in the epidermis. The increased levels of ceramide were accompanied by a significantly increased secretion of granulocyte-macrophage colony-stimulating factor as well as by a significantly down-regulated expression of acid-ceramidase at both the gene and protein levels. Taken together, our results underscore the superiority of this reconstructed human epidermal keratinization model to analyze factors that regulate ceramide synthesis, especially in human SC.

Yamamoto H.,Tokyo University of Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

Application of white LEDs is extended toward high-output light sources, e.g. for automotive headlights, and better spectral matching with optical filters for LCD backlighting. To meet such new demands, phosphor materials have been investigated with focus on their luminescence spectra, temperature characteristics and reliability. The conventional yellow phosphor based on Y3Al5O12:Ce3+ has excellent performance as a single phosphor combined with a blue LED. More recently developed nitrido- or oxonitrido-silicates activated with Eu2+ are also promising materials showing green to red luminescence depending on a composition and high thermal and chemical stability. And yet, demands for specific application have been made clear and strong. This paper reviews the present status and challenging goals of phosphors in the next stage further to make progress in white LEDs. © 2010 Copyright SPIE - The International Society for Optical Engineering.

Nakajima K.,Tokyo University of Technology
Procedia Computer Science | Year: 2013

The multigrid method used with OpenMP/MPI hybrid parallel programming models is expected to play an important role in large-scale scientific computing on post-peta/exa-scale supercomputer systems. In the present work, the effect of sparse matrix storage formats on the performance of parallel geometric multigrid solvers was evaluated, and a new data structure for the Ellpack-Itpack (ELL) format is proposed. The proposed method is implemented for pGW3D-FVM, a parallel code for 3D groundwater flow simulations using the multigrid method, and the robustness and performance of the code was evaluated on up to 4,096 nodes (65,536 cores) of the Fujistu FX10 supercomputer system at the University of Tokyo. The parallel multigrid solver using the ELL format with coarse grid aggregation provided excellent performance improvement in both weak scaling (13%-35%) and strong scaling (40%-70%) compared to the original code using the CRS format. © 2013 The Authors. Published by Elsevier B.V.

Yoshimura T.,Tokyo University of Technology
Journal of Lightwave Technology | Year: 2015

Using the finite-difference time-domain method, we simulated the growth of self-organized waveguides between a 3-μm-wide micro-scale waveguide and a 600-nm-wide nano-scale waveguide, which has a luminescent target on its core edge. The two waveguides are placed together, with gap sizes ranging from 16 to 64 μm, in a photo-induced refractive-index increase-type material. When a 400 nm wavelength write beam is introduced from the micro-scale waveguide, luminescence is generated by the luminescent target. A waveguide is then gradually self-organized between the two waveguides, even when a lateral misalignment of 600 nm exists between them, and provides a self-aligned optical coupling with a coupling loss of 1.5-1.8 dB. This indicates that the self-organized waveguide can be used as an optical solder to connect a micro-scale waveguide in a multi-chip module or printed circuit board to a nano-scale waveguide in a large-scale integrated circuit. The optimum writing time required to attain the minimum coupling loss increases with increasing lateral misalignment. The dependence of the optimum writing time on the misalignment is reduced with increasing gap distance, and the dependence almost vanishes when the gap distance is 64 μm, thus enabling unmonitored optical solder formation. © 1983-2012 IEEE.

Nakamura H.,Tokyo University of Technology
Analytical Methods | Year: 2010

Rapid economic growth in Japan resulted in serious organic pollution in the 1960s. In contrast, recent organic pollution is caused primarily by phosphorus-based anthropogenic eutrophication, which also induces heavy metal pollution. In the present review, causes of the recent organic pollution are briefly introduced, and our approaches, based on studies of environmental water biosensing methods as tools for estimating the degrees of the recent organic pollution, eutrophication, and heavy metal pollution, are introduced. © The Royal Society of Chemistry 2010.

Multi-electrode arrays (MEAs) can be used for noninvasive, real-time, and long-term recording of electrophysiological activity and changes in the extracellular chemical microenvironment. Neural network organization, neuronal excitability, synaptic and phenotypic plasticity, and drug responses may be monitored by MEAs, but it is still difficult to measure presynaptic activity, such as neurotransmitter release, from the presynaptic bouton. In this study, we describe the development of planar carbon nanotube (CNT)-MEA chips that can measure both the release of the neurotransmitter dopamine as well as electrophysiological responses such as field postsynaptic potentials (fPSPs) and action potentials (APs). These CNT-MEA chips were fabricated by electroplating the indium-tin oxide (ITO) microelectrode surfaces. The CNT-plated ITO electrode exhibited electrochemical response, having much higher current density compared with the bare ITO electrode. Chronoamperometric measurements using these CNT-MEA chips detected dopamine at nanomolar concentrations. By placing mouse striatal brain slices on the CNT-MEA chip, we successfully measured synaptic dopamine release from spontaneous firings with a high S/N ratio of 62. Furthermore, APs and fPSPs were measured from cultured hippocampal neurons and slices with high temporal resolution and a 100-fold greater S/N ratio. Our CNT-MEA chips made it possible to measure neurotransmitter dopamine (presynaptic activities), postsynaptic potentials, and action potentials, which have a central role in information processing in the neuronal network. CNT-MEA chips could prove useful for in vitro studies of stem cell differentiation, drug screening and toxicity, synaptic plasticity, and pathogenic processes involved in epilepsy, stroke, and neurodegenerative diseases. Copyright © 2013 Elsevier B.V. All rights reserved.

Tokyo University of Technology | Date: 2010-03-10

A substantially spherical rotor can be controlled with accuracy even in a relatively low speed rotation. In controlling rotational motions of a rotor 3 of a spherical ultrasonic motor 1, phases of voltages to be applied to three stators 9a, 9b, 9c are determined to set the direction of a rotation axis of the rotor 3. Frequencies of voltages to be applied to the three stators 9a, 9b, 9c are adjusted to control the rotation speed of the rotor 3. Thereby, control with high accuracy is enabled in a relatively low speed rotation.

A triprenyl phenol compound represented by the following formula (II) and (III) and having a thrombolysis-enhancing activity, and an efficient method for producing the triprenyl phenol compound. In formula (II) and (III), R^(1 )represents an aromatic group having as a substituent or as a part of a substituent at least one member selected from the group consisting of a carboxyl group, a hydroxyl group, a sulfonic acid group and a secondary amino group, or an aromatic group which comprises a secondary amino group and may comprise nitrogen; R^(4 )in the general formula (III) represents an aromatic amino acid residue represented by the general formula (III-1) below; X represents CHY(CH_(3))_(2)Z; and Y and Z are respectively H or OH or together form a single bond: (III-1) wherein R^(5 )represents a hydroxyl group which may be present or absent; and n represents an integer of 0 or 1.

Taiho Pharmaceutical Co and Tokyo University of Technology | Date: 2013-09-30

To provide an agent for treating osteoporosis, comprising an acyl thiourea compound represented by the following formula (I) or a salt thereof as an active ingredient: wherein, R^(1 )represents an optionally substituted C_(1-6 )alkyl group; R^(2 )represents a fluorine atom or a chlorine atom; and R^(3 )represents a hydrogen atom, a fluorine atom, or a chlorine atom.

Loading Tokyo University of Technology collaborators
Loading Tokyo University of Technology collaborators