Tokyo, Japan

Tokyo University of Science , formerly "Science University of Tokyo", informally Rikadai or simply Ridai is a Japanese private university in Shinjuku, Tokyo, Japan. Wikipedia.

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University of Toyama, Kracie Pharma Ltd., National Cancer Center and Tokyo University of Science | Date: 2015-04-10

The purpose of the present invention is to provide an anticancer agent for potentiating an antitumor effect, alleviating side effects, and further extending the survival rate by concomitant use with a component having an anticancer effect. An anticancer agent combining arctigenin and a component other than arctigenin that has an anticancer effect, in which the anticancer agent may be a combination drug or may be a kit configured from a formulation containing arctigenin and a formulation containing a component that has an anticancer effect, and the concomitant use of arctigenin and the component having an anticancer effect more strongly inhibits tumor growth and reduces the proportion of cancer stem cells in the tumor, making it possible to extend the total survival time and to alleviate side effects caused by the component having an anticancer effect.

Wako Pure Chemical Industries Ltd. and Tokyo University of Science | Date: 2015-04-21

It is an object of the present invention to provide an electrode having superior charge-discharge capacity, even in the case of using an active material containing silicon. The present invention relates to a binder for a lithium cell comprises a polymer having a monomer unit derived from acrylic acid, and 1 to 2 kinds of monomer units derived from the compound shown by the general formula (I), the general formula (II), or the general formula (III), as constituents, and cross-linked by a cross-linking agent selected from the compounds described by the following general formulae [1] to [13], and the polymer described by the following general formula [14], a composition for producing an electrode of a lithium cell comprising 1) an active material containing silicon, 2) a conductive assistant, and 3) the above-described binder for a cell, and an electrode for a lithium cell having 1) an active material containing silicon, 2) a conductive assistant, 3) the above-described binder for a cell, and (4) a current collector.

A three-dimensional printing system (1) includes: a head (2) to which a first continuous material (FL) including a resin and a second continuous material (FB) including fibers are fed; a platform (3) on which a printing material based on the first and second continuous materials from the head is stacked; a cutting device (10) which is capable of cutting at least fibers; and a controller (5) which controls an operation device including at least one of the head, the platform, and the cutting device.

Wako Pure Chemical Industries Ltd. and Tokyo University of Science | Date: 2017-03-01

It is an object of the present invention to provide an electrode having superior charge-discharge capacity, even in the case of using an active material containing silicon. The present invention relates to a binder for a lithium cell comprises a polymer having a monomer unit derived from acrylic acid, and 1 to 2 kinds of monomer units derived from the compound shown by the general formula (I), the general formula (II), or the general formula (III), as constituents, and cross-linked by a cross-linking agent selected from the compounds described by the following general formulae [1] to [13], and the polymer described by the following general formula [14], a composition for producing an electrode of a lithium cell comprising 1) an active material containing silicon, 2) a conductive assistant, and 3) the above-described binder for a cell, and an electrode for a lithium cell having 1) an active material containing silicon, 2) a conductive assistant, 3) the above-described binder for a cell, and (4) a current collector.

Hayama H.,Tokyo University of Science | Hoshi N.,Tokyo University of Science
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

Auxiliary resonant snubber inverters (RSIs) have been proposed as a solution of demands for inverter, which are high efficiency and low EMI. In RSI, zero voltage switching (ZVS) on the inverter main switches is achieved by use of the auxiliary circuit; however, additional conduction loss increases simultaneously. The operating frequency of the auxiliary circuit in RSI can be reduced to a half of switching transition of a main switch when lossless snubber commutation, in which ZVS can be achieved without using auxiliary circuit by using output current, is used. As a result, additional conduction loss can be suppressed. However, in this scheme, ZVS turn-on on main switch is failed near zero output current when dead-time was constant. As a solution for this problem, adjustable dead-time control scheme for RSI has been proposed. Adjustable dead-time control has not been applied to a rectifier with auxiliary resonant snubber circuit auxiliary resonant snubber rectifier (RSR)in the previous work. Thus, adjustable dead-time control is applied to RSR in this paper. This paper shows a control scheme for RSR. Moreover, the effectiveness of adjustable dead-time control by comparing between the adjustable and the fixed dead-time control is described. © 2011 IEEE.

Katayama N.,Tokyo University of Science | Kogoshi S.,Tokyo University of Science
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

One of the present challenges of Polymer electrolyte membrane fuel cells (PEMFCs) is to enhance their durability. It is known that maintaining the load conditions of PEMFCs appropriately could improve the lifetime of PEMFC. We proposed the method of smoothing the output current of PEMFCs by charging or discharging electrical double layer capacitors (EDLCs). To achieve such purpose, we developed a multi-port bidirectional DC-DC converter, which is able to control the energy flow among a fuel cell, EDLC, and load, and to regulate terminal voltages proper to these devices. The aim of this study is to evaluate the frequency characteristics of the proposed hybrid power system. The evaluation contributes to design a long life fuel cell system. The frequency characteristics of the proposed converter system for mitigating PEMFC degradation have been evaluated. To investigate the relationship between the load and the fuel cell currents, frequency response characteristics are measured. The converter can smooth the output current of the fuel cell although the load current fluctuate below 100 Hz. © 2011 IEEE.

Matsuda A.,Tokyo University of Science | Koizumi H.,Tokyo University of Science
ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings | Year: 2016

This paper proposes a high step-up interleaved converter with coupled inductor and voltage-lift technique. The proposed converter achieves high voltage gain by employing coupled inductor and voltage-lift technique. Moreover, low input current ripple is realized by using interleaved technique. The energy in the leakage inductance of the coupled inductor is recycled to the output load. The voltage stresses on the main switches are reduced and the voltage spikes across the main switches are alleviated. This paper shows a theoretical analysis in steady-state and experimental results with a small-scale prototype circuit. © 2016 IEEE.

Kamono K.,Tokyo University of Science | Ueda Y.,Tokyo University of Science
2016 IEEE Power and Energy Society Innovative Smart Grid Technologies Conference, ISGT 2016 | Year: 2016

As the amount of photovoltaic systems in distribution system increases, the need to grasp areal photovoltaic output power increases. Assuming Japanese smart grid system, this paper proposes a method to estimate areal photovoltaic output power of distribution system in real-time using smart meters, a pyranometer, and IT switches. By using 30 minute integrated areal photovoltaic output energy obtained by smart meters, the proposed method can perform estimation accurately throughout the year. Also, to track fast fluctuations of photovoltaic output power, the proposed method estimates low and high frequency components separately. To apply frequency classification in real-time, the proposed method uses a frequency classification method using a sliding window and linear fit. Simulations were performed using real measured data, and the proposed method was able to improve a previously proposed method and estimate areal photovoltaic output power with root mean square error less than 4% of the system capacity. © 2016 IEEE.

Ogawa T.,Tokyo University of Science | Ueda Y.,Tokyo University of Science
2016 IEEE Power and Energy Society Innovative Smart Grid Technologies Conference, ISGT 2016 | Year: 2016

Forecasting insolation of the next day is expected as a method to deal with photovoltaic power fluctuation. In general, extending the training period as long as possible is desirable for the training of a machine learning. However, annual variation of global horizontal insolation could affect the accuracy of insolation forecast. Thus, the objective of this study is to forecast clearness index and to investigating the forecast error of forecast models with various training periods. The proposed clearness index forecast model uses temperature, absolute humidity, cloudiness at each level from GPV-MSM, and air mass as input data into support vector regression. Also, the model was divided into three models depending on the solar height. Results showed that root mean square error, mean absolute error, and mean bias error were better compared to the insolation forecast. Consequently, the clearness index forecast model is preferable to eliminate a negative effect of annual variation. © 2016 IEEE.

Yoshida Y.,Tokyo University of Science | Ueda Y.,Tokyo University of Science
2016 IEEE Power and Energy Society Innovative Smart Grid Technologies Conference, ISGT 2016 | Year: 2016

Massive PV introduction induces difficult power supply-demand balance adjustment. As one of solutions, a PV system and a Solar Hot-Water Supply System which is a hybrid system of a Solar Thermal Water Heater and a Heat Pump Water Heater is combined. In optimization of these configuration, it is necessary to consider the optimization of multiple objectives such as cost and energy efficiency. However, it is difficult to satisfy these objectives simultaneously since these are trade-offs. In this paper, we conducted to find pareto optimal solutions by Multi-Objective Particle Swarm Optimization which is a kind of an evolutionary computing. To facilitate the solution search within the constraints conditions, we gave a flag to the excess and run-out of the heat storage amount. Thereby, we could find quasi-optimal solutions according to each objective, and conducted a search twice for solutions by Multi-Objective Particle Swarm Optimization with fixed configuration to find better solutions with respect to operation. As a result, the evaluation values of all objective functions are improved. © 2016 IEEE.

Arai M.,Tokyo University of Science
Journal of Pressure Vessel Technology, Transactions of the ASME | Year: 2017

In this paper, the procedure which can estimate creep exponent and coefficient in Norton's law of the miniature sample from the impression size rather than the penetration depth is discussed based upon a high-temperature creep indentation test. First, an analytical solution related to the change in the impression size with dwelling time at an indentation load is solved by using a well-known problem of infinite creeping media embedding spherical cavity subjected to an inner pressure which characterizes an indentation load. The applicability of the formula to elastic-plastic-creeping model resembling an actual response is checked by conducting a nonlinear finite-element analysis combined with contact option. Finally, creep indentation tests are conducted for a high-Cr ferritic heat-resisting steel, grade 122. It is shown that the creep parameters at a lower stress level can be estimated at temperature 873 K. Copyright © 2017 by ASME.

Trifluoromethyl-substituted benzoic anhydrides as structural congeners of 2-methyl-6-nitrobenzoic anhydride (MNBA) were prepared and investigated for comparative reactivity in the synthesis of carboxylic esters and macrolactones. 2-Fluoro-6-(trifluoromethyl)benzoic anhydride (FTFBA) was found to be a promising dehydrating agent in the presence of 4-(dimethylamino)pyridine (DMAP), and was successfully employed in the synthesis of threo-aleuritic acid lactone in good yield with high chemoselectivity. © 2017 The Japan Institute of Heterocyclic Chemistry Received.

Hirakawa T.,Tokyo University of Science | Hasegawa J.,Tokyo University of Science | White C.I.,University Blaise Pascal | Matsunaga S.,Tokyo University of Science
Plant Journal | Year: 2017

Plants have various defense mechanisms against environmental stresses that induce DNA damage. Genetic and biochemical analyses have revealed the sensing and signaling of DNA damage, but little is known about subnuclear dynamics in response to DNA damage in living plant cells. Here, we observed that the chromatin remodeling factor RAD54, which is involved in DNA repair via the homologous recombination pathway, formed subnuclear foci (termed RAD54 foci) in Arabidopsis thaliana after induction of DNA double-strand breaks. The appearance of RAD54 foci was dependent on the ATAXIA-TELANGIECTASIA MUTATED–SUPPRESSOR OF GAMMA RESPONSE 1 pathway, and RAD54 foci were co-localized with γH2AX signals. Laser irradiation of a subnuclear area demonstrated that in living cells RAD54 was specifically accumulated at the damaged site. In addition, the formation of RAD54 foci showed specificity for cell type and region. We conclude that RAD54 foci correspond to DNA repair foci in A. thaliana. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd

Matsuzaki R.,Tokyo University of Science | Yamamoto K.,Tokyo University of Science | Todoroki A.,Tokyo Institute of Technology
Composite Structures | Year: 2017

The present study proposes crack swarm inspection (CSI) for estimating crack location and size in carbon composite laminates from the surface voltage distribution. This technique generates a large number of virtual microscopic cracks, and calculates the surface voltage distribution of the composites using anisotropic electric potential functions and doublet strings. Using genetic algorithms, the virtual microscopic cracks formed a swarm to coincide with the measured surface voltage; thereby, the crack sizes and locations are estimated from the position of the crack swarm. The CSI was applied to crack detection in carbon laminated composite plates; it was confirmed that the existence of cracks in each partitioned section was detected with >80% probability, in reference to the crack location and size information. Furthermore, we also confirmed that the estimation accuracy was affected by the electric current density in the thickness direction, and addressed the recommended electrode interval based on the minimum size of the estimated crack. © 2016 Elsevier Ltd

Kaneko N.,Tokyo University of Science | Iwamura K.,Tokyo University of Science
2016 IEEE 5th Global Conference on Consumer Electronics, GCCE 2016 | Year: 2016

An asymmetric secret sharing scheme (A-SSS) can set the number of servers at less than k, because it makes up to k-1 shares from one key of the owner of the secret. Therefore, the secret is not revealed even if all the servers are attacked. However, when the owner's key is stolen and attacked, shares may be leaked. Therefore, in this paper we propose a proactive secret sharing scheme suitable for an A-SSS. Our scheme realizes a reduction in the large volume of communications as compared with conventional proactive secret sharing schemes. © 2016 IEEE.

Su M.,Tokyo University of Science | Kim B.,Tokyo University of Science
2016 IEEE CPMT Symposium Japan, ICSJ 2016 | Year: 2016

In 2012, a novel energy harvesting approach was proposed and named TENG (Triboelectric Nano Generator), which is based on the combination of electrification effect and electrostatic induction. Due to remarkable properties, such as high-performance and the use of environmentally friendly materials, TENG has raised increasing interest. Several techniques have been developed to enhance the power density, including structural optimization, operation mechanism, surface texturing and hybrid TENG. Recently, a power density of up to a 19 mW/cm2 has been reached with an output power larger than 1.5 W. Herein, we propose a very simple and cost-efficient approach to fabricate high-performance TENG based on paper and graphite pencil. In order for TEG to make an impact in real life applications, further improvements are needed in particular in the choice of the pair of electrification materials beyond the conventional materials. The materials used to create the TEG system should ideally be designed to be wearable on the body (or even be implantable) and should therefore be flexible, bio-friendly and biodegradable, and ultimately transparent. Here, not only a paper, a promising material of silk fibroin is successfully utilized to construct transparent TEGs. Several technical challenges have been successfully addressed and are shown. On the other hands, we propose a novel device, which can utilize ambient vibration with wideband and low frequencies. As the power sources of wireless sensors, batteries are mainly utilized until now. These days, devices of energy harvesting become more focused. Energy harvesting is a methodology of scavenging power from ambient energy sources such as solar, thermal and vibration without the need for batteries. Due to high stiffness of piezo electric energy harvesters, resonant frequency of the piezo electric energy harvesters tends to be much higher than ambient vibrational frequency. To solve these problems, the proposed energy-harvesting device is to utilize a stochastic resonance. This paper reports a new hybrid energy harvesting approach which combines triboelectricity and piezoelectricity based on low-frequency stochastic resonance. A vibration configuration was well designed to enhance the conversion efficiency of mechanical energy to electricity via the stochastic vibration mechanism. Furthermore, the electric output performance of the proposed generator is significantly strengthened by adding triboelectric effects to bi-stable structured energy harvester, showing attractive potential for generating high output by harvesting low-frequency energy, typically the living environmental energy like the body motion of human. © 2016 IEEE.

We show that 8ps pulses are arbitrarily wavelength-converted with efficiency of -6dB by using a 50mm-long quasi-phase matched lithium niobate. The result suggests possibility of selective and tunable wavelength conversion of 40-Gbps WDM signals. © OSA 2016.

Kovacevic G.,Tokyo University of Science | Yamashita S.,Tokyo University of Science
Optics InfoBase Conference Papers | Year: 2016

We estimate the thermal effect in single layer graphene and its potential use in thermally activated optical modulators. We show it to be significant in devices based on evanescent field coupling, while in normal-incidence regime it is negligible. © OSA 2016.

Shirahata T.,Tokyo University of Science | Yamashita S.,Tokyo University of Science
2016 Conference on Lasers and Electro-Optics, CLEO 2016 | Year: 2016

We realized full-range measurement without mirror images and nonlinear sweep compensation simultaneously in SS-OCT system by using a digital coherent receiver for telecommunication. Imaging depth is improved from 0.7mm to 3.6mm with resolution of 85μm. © 2016 OSA.

Shirato Y.,Tokyo University of Science | Muraguchi M.,Tokyo University of Science
European Microwave Week 2016: "Microwaves Everywhere", EuMW 2016 - Conference Proceedings; 46th European Microwave Conference, EuMC 2016 | Year: 2016

The authors have proposed the signal decomposition technique as one of the powerful solution to mitigate the large PAPR to be addressed in OFDM transmitters especially on mobile terminals. In order to enhance the receiver SNR, the simple noise elimination techniques working together with the signal decomposition have also been proposed, that eliminates the noise added on the decomposed constant amplitude on-off-signals by taking advantage of the knowledge of their constant amplitude at the receiver. It is shown that the proposed signal decomposition technique improves the PAPR by 4dB and doubles the PAE at the CCDF (Complementary Cumulative Distribution Function) of 1%. In addition to the analysis of receiver SNR, the BER performances are demonstrated when the decomposed signals are transmitted over a 2×2 MIMO system. © 2016 EuMA.

Fukuchi Y.,Tokyo University of Science
2016 IEEE Photonics Conference, IPC 2016 | Year: 2016

We investigate bandwidth limitation of tunable wavelength conversion from an arbitrary wavelength to another arbitrary one using the cascaded second-order nonlinear effect in quasi-phase matched lithium niobate waveguides. Critical pulse width to be wavelength-converted is proportional to the device length, and its ratio is 1.6ps/cm. © 2016 IEEE.

We demonstrate highly efficient and tunable wavelength conversion of 40-Gbps NRZ signals employing the cascade of sum frequency mixing and difference frequency mixing in a 50-mm-long quasi-phase matched lithium niobate waveguide. The result suggests possibility of selective and tunable wavelength conversion of 40-Gbps DWDM channels. © 2016 IEEE.

Mizoguchi T.,Tokyo University of Science | Watabe S.,Tokyo University of Science | Nikuni T.,Tokyo University of Science
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2017

We study nonlinear mixing effects among quadrupole modes and scissors modes in a harmonically trapped Bose-Einstein condensate. Using a perturbative technique in conjunction with a variational approach with a Gaussian trial wave function for the Gross-Pitaevskii equation, we find that mode mixing occurs selectively. Our perturbative approach is useful in gaining a qualitative understanding of the recent experiment [M. Yamazaki et al., J. Phys. Soc. Jpn. 84, 44001 (2015)JUPSAU0031-901510.7566/JPSJ.84.044001], exhibiting a beating phenomenon of the scissors mode as well as a modulation phenomenon of the low-lying quadrupole mode by the high-lying quadrupole mode frequency. Within the second-order treatment of the nonlinear mode coupling terms, our approach predicts all the spectral peaks obtained by the numerical simulation of the Gross-Pitaevskii equation. © 2017 American Physical Society.

Zhanikeev M.,Tokyo University of Science
International Journal of Information Technologies and Systems Approach | Year: 2017

Many years of research on Content Delivery Networks (CDNs) offers a number of effective methods for caching of content replicas or forwarding requests. However, recently CDNs have aggressively started migrating to clouds. Clouds present a new kind of distribution environment as each location can support multiple caching options varying in the level of persistence of stored content. A subclass of clouds located at network edge is referred to as fog clouds. Fog clouds help by allowing CDNs to offload popular content to network edge, closer to end users. However, due to the fact that fog clouds are extremely heterogeneous and vary wildly in network and caching performance, traditional caching technology is no longer applicable. This paper proposes a multi-level caching technology specific to fog clouds. To deal with the heterogeneity problem and, at the same time, avoid centralized control, this paper proposes a function that allows CDN services to discover local caching facilities dynamically, at runtime. Using a combination of synthetic models and real measurement dataset, this paper analyzes efficiency of offload both at the local level of individual fog locations and at the global level of the entire CDN infrastructure. Local analysis shows that the new method can reduce inter-cloud traffic by between 16 and 18 times while retaining less than 30% of total content in a local cache. Global analysis further shows that, based on existing measurement datasets, centralized optimization is preferred to distributed coordination among services. © 2017, IGI Global.

Miyauchi S.,Tokyo University of Science | Watanabe K.,Tokyo University of Science
Journal of the Physical Society of Japan | Year: 2017

A time-dependent density functional theory simulation demonstrated the sequential dynamics of electron excitation and emission from a silicene nanoribbon under a femtosecond laser pulse. The mechanism for the multiphoton absorption processes that are responsible for the kinetic-energy spectra of emitted electrons was elucidated using Kohn-Sham potentials and the decomposition scheme. ©2017 The Physical Society of Japan.

Takahashi A.,Tokyo University of Science | Kanazawa M.,Tokyo University of Science
MATEC Web of Conferences | Year: 2017

In this study, we first present the molecular dynamics (MD) simulation of dislocation behavior in a spinodally decomposed Fe-Cr alloy. The MD simulation is used for exploring the nature of the interaction between a dislocation and the spinodal decomposition without any specific assumptions. In order to classify the interaction mechanism, dislocation dynamics (DD) simulations of the interaction between a dislocation and the spinodal decomposition are performed. In the simulations, we controlled the interaction mechanism by adding and removing the atomistic mechanism. The simulation results clearly illustrate that the atomistic mechanism can be negligible in determining the critical resolved shear stress (CRSS) of spinodally decomposed Fe-Cr alloys, and the internal stress generated by the lattice constant mismatch is a dominant mechanism. These findings are very useful for simplifying the analysis of the mechanism of material strength change due to the spinodal decomposition. Particularly in the analysis using the DD simulations, the required computational effort for simulating the dislocation behavior is greatly reduced by taking into account only the internal stress without the atomistic dislocation core influence. © The Authors, published by EDP Sciences, 2017.

Shibata H.,Chiba Institute of Technology | Shibata H.,Tokyo University of Science
Journal of Oleo Science | Year: 2017

In this review, the synthesis of inorganic materials with various properties using amphiphilic molecules is examined. Amphiphilic molecules are used for the formation of highly ordered mesostructures and the surface modification. Two examples of the mesostructures are crystalline mesoporous titania (TiO2) and the novel visible light responsive mesostuructured titania modified with dye in the pores, which can be fabricated using the molecular self-assemblies of amphiphiles as templates. Surface modification using amphiphilic molecules enables the construction of self-assembled arrays of silica particles and the preparation of a film that can control adsorption/desorption behavior of bovine serum albumin (BSA) by light irradiation. © 2017 by Japan Oil Chemists’ Society.

Ando N.,Tokyo University of Science | Kanzaki R.,Tokyo University of Science
Arthropod Structure and Development | Year: 2017

The use of mobile robots is an effective method of validating sensory-motor models of animals in a real environment. The well-identified insect sensory-motor systems have been the major targets for modeling. Furthermore, mobile robots implemented with such insect models attract engineers who aim to avail advantages from organisms. However, directly comparing the robots with real insects is still difficult, even if we successfully model the biological systems, because of the physical differences between them. We developed a hybrid robot to bridge the gap. This hybrid robot is an insect-controlled robot, in which a tethered male silkmoth (Bombyx mori) drives the robot in order to localize an odor source. This robot has the following three advantages: 1) from a biomimetic perspective, the robot enables us to evaluate the potential performance of future insect-mimetic robots; 2) from a biological perspective, the robot enables us to manipulate the closed-loop of an onboard insect for further understanding of its sensory-motor system; and 3) the robot enables comparison with insect models as a reference biological system. In this paper, we review the recent works regarding insect-controlled robots and discuss the significance for both engineering and biology. © 2017 Elsevier Ltd.

Okamoto K.,Tokyo University of Science | Aikawa N.,Tokyo University of Science
Midwest Symposium on Circuits and Systems | Year: 2017

Vibrating sensors are used as a sensor to measure such as pressures, forces, accelerations and densities. In particular, a tuning fork sensor is suitable as a sensor for a electronic balance due to high sensitivities to the force and its long term stabilities. However, the tuning fork sensor is affected by a temperature and an air density. Therefore, the tuning fork sensor should be compensated the effects of them. In a conventional method, the tuning fork sensor could not be compensated adequately for an abrupt change in the air density due to a delay of a smoothing filter. In this paper, we propose accurate compensation method of a drift of the tuning fork sensor which is caused by a changing the air density. Applying Kalman filter, the drift of the tuning fork sensor can be very small even when the abrupt change in the air density and there is a noise in a measured air pressure and its frequency. © 2016 IEEE.

Takemoto K.,Yokohama City University | Takemoto K.,Japan Science and Technology Agency | Iwanari H.,Tokyo University of Science | Tada H.,Yokohama City University | And 5 more authors.
Nature Biotechnology | Year: 2017

The synaptic delivery of neurotransmitter receptors, such as GluA1 AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptors, mediates important processes in cognitive function, including memory acquisition and retention. Understanding the roles of these receptors has been hampered by the lack of a method to inactivate them in vivo with high spatiotemporal precision. We developed a technique to inactivate synaptic GluA1 AMPA receptors in vivo using chromophore-assisted light inactivation (CALI). We raised a monoclonal antibody specific for the extracellular domain of GluA1 that induced effective CALI when conjugated with a photosensitizer (eosin). Mice that had been injected in the CA1 hippocampal region with the antibody conjugate underwent a fear memory task. Exposing the hippocampus to green light using an implanted cannula erased acquired fear memory in the animals by inactivation of synaptic GluA1. Our optical technique for inactivating synaptic proteins will enable elucidation of their physiological roles in cognition. © 2017 Nature America, Inc., part of Springer Nature. All rights reserved.

Ito H.,University of Tokyo | Nishinari K.,Tokyo University of Science
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2017

The effects of burstiness in complex networks have received considerable attention. In particular, the effects on temporal distance and delays in the air transportation system are significant owing to their huge impact on our society. Therefore, in this paper, the temporal distance of empirical U.S. flight schedule data is compared with that of regularized data without burstiness to analyze the effects of burstiness. The temporal distance is calculated by a graph analysis method considering flight delays, missed connections, flight cancellations, and congestion. In addition, we propose two temporal distance indexes based on passengers' behavior to quantify the effects. As a result, we find that burstiness reduces both the scheduled and the actual temporal distances for business travelers, while delays caused by missed connections and congestion are increased. We also find that the decrease of the scheduled temporal distance by burstiness is offset by an increase of the delays for leisure passengers. Moreover, we discover that the positive effect of burstiness is lost when flight schedules are overcrowded. © 2017 American Physical Society.

Gastrointestinal stromal tumors (GISTs) are caused by gain-of-function mutations in the Kit receptor tyrosine kinase. Most primary GIST patients respond to the Kit inhibitor imatinib, but this drug often becomes ineffective because of secondary mutations in the Kit kinase domain. The characteristic intracellular accumulation of imatinib-sensitive and -resistant Kit protein is well documented, but its relationship to oncogenic signaling remains unknown. Here, we show that in cancer tissue from primary GIST patients as well as in cell lines, mutant Kit accumulates on the Golgi apparatus, whereas normal Kit localizes to the plasma membrane (PM). In imatinib-resistant GIST with a secondary Kit mutation, Kit localizes predominantly on the Golgi apparatus. Both imatinib-sensitive and imatinib-resistant Kit (Kit(mut)) become fully auto-phosphorylated only on the Golgi and only if in a complex-glycosylated form. Kit(mut) accumulates on the Golgi during the early secretory pathway, but not after endocytosis. The aberrant kinase activity of Kit(mut) prevents its export from the Golgi to the PM. Furthermore, Kit(mut) on the Golgi signals and activates the phosphatidylinositol 3-kinase–Akt (PI3K–Akt) pathway, signal transducer and activator of transcription 5 (STAT5), and the Mek–Erk pathway. Blocking the biosynthetic transport of Kit(mut) to the Golgi from the endoplasmic reticulum inhibits oncogenic signaling. PM localization of Kit(mut) is not required for its signaling. Activation of Src-family tyrosine kinases on the Golgi is essential for oncogenic Kit signaling. These results suggest that the Golgi apparatus serves as a platform for oncogenic Kit signaling. Our study demonstrates that Kit(mut)’s pathogenicity is related to its mis-localization, and may offer a new strategy for treating imatinib-resistant GISTs.Oncogene advance online publication, 13 February 2017; doi:10.1038/onc.2016.519. © 2017 The Author(s)

Inokuma Y.,Tokyo University of Science
Drug Safety | Year: 2017

Two Japanese regulatory agencies, the Ministry of Health, Labour and Welfare and the Pharmaceuticals and Medical Devices Agency announced the implementation of a new review system called ‘Conditional Approval,’ specifically for the emerging field of regenerative medicine, in an amendment to the Pharmaceutical Affairs Act in 2014. Regenerative medicine was regulated in the category of ‘Medical Devices’ prior to the amendment and was not covered by the Relief Service, a system that provides financial aid to people who have experienced an adverse drug reaction and developed serious side effects as a result. Through the amendment, regenerative medicine is defined as a new category and is covered by the Relief Service under the amended Pharmaceutical Affairs Act, called the ‘Act on Securing Quality, Efficacy and Safety of Pharmaceuticals, Medical Devices, Regenerative and Cellular Therapy Products, Gene Therapy Products, and Cosmetics’ (PMD Act). This amendment allows the use of Relief Service data for pharmacovigilance activities, making the Relief Service the third adverse drug reaction reporting route in addition to the existing reporting routes from marketing authorization holders and healthcare providers. For optimum incorporation and use of this Relief Service data, earlier access should be allowed even before the reports from the Pharmaceuticals and Medical Devices Agency to the Ministry of Health, Labour and Welfare are finalized, which is mandatory under the current PMD Act. © 2017 Springer International Publishing Switzerland

Akakura T.,Tokyo University of Science | Ishii T.,Tokyo University of Science
Proceedings of 2016 IEEE International Conference on Teaching, Assessment and Learning for Engineering, TALE 2016 | Year: 2016

In this paper, we propose a model of the problem-solving process for learning Patent Act, noting that legal texts can be expressed as logical structures. We also develop a learning support system for engineering students that uses this model. © 2016 IEEE.

Ishii T.,Tokyo University of Science | Akakura T.,Tokyo University of Science
Proceedings of 2016 IEEE International Conference on Teaching, Assessment and Learning for Engineering, TALE 2016 | Year: 2016

To increase learning quality, instructors and learners must make efforts toward improving their lectures. As a start, instructors and learners need to share context and know-how, and cooperate for lecture improvements. We propose a framework for capturing learning states and context, and for better searches for lecture improvements. Specifically, this framework records and analyzes performed actions in lectures that contains efforts toward improvements, their context, and the result of the actions as described in lecture evaluations. © 2016 IEEE.

Jeon S.,Tokyo University of Science | Toshiyoshi H.,Tokyo University of Science
Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS) | Year: 2017

We report a free space optical (FSO) communication system for bi-directional passive optical network (PON) based on a MEMS spatial light modulator (SLM). A piezoelectric PZT scanner is used to display a marker image to invite a passive optical terminal (POT) and to keep the optical link even when the POT moves. Unlike wireless network that broadcasts radio signals, the FSO system in this work provides high security data transmission. © 2017 IEEE.

Ohshima H.,Tokyo University of Science
Journal of Biomaterials Science, Polymer Edition | Year: 2017

An approximate analytic expression is derived for the interaction energy between two parallel plates covered with a polyelectrolyte brush layer in an electrolyte solution. The interaction energy has three components: electrostatic interaction energy between two brush layers before and after their contact, steric interaction energy between two brush layers after their contact, and the van der Waals interaction energy between the cores of the plates. It is shown that these three components are of the same order of magnitude and contribute equally to the total interaction energy between two polyelectrolyte-coated plates in an electrolyte solution. On the basis of Derjaguin’s approximation, an approximate expression for the interaction energy between two spherical particles covered with polyelectrolyte brush layers is also derived. © 2017 Informa UK Limited, trading as Taylor & Francis Group

Ikhlayel M.,Tokyo University of Science | Nguyen L.H.,Tokyo University of Science
Sustainable Development | Year: 2017

We aim in this paper to address the sustainability challenge of how an integrated approach can lead to figuring out solutions to complex issues for modern societies. We reviewed papers related to integrated water resource management (IWRM) and integrated solid waste management (ISWM) to advocate some innovative concepts and methodologies of sustainability science. An investigation of the concepts of IWRM and ISWM over various sustainability science research clusters and dimensions is presented. Water resource management projects at different scales and across various geographical boundaries are reviewed to understand the IWRM approach. The ISWM approach is discussed with regard to research topics and methodologies from selected case studies in developed and developing countries. We sought to look at various definitions, the integrated elements, and the similarities and differences between the two approaches. We also present our definitions for each approach. Our findings show how integrated thinking can help in achieving sustainable development. Finally, we present our recommendations for possible implications to the integrated approach in order to accelerate the process of sustainable development. © 2017 John Wiley & Sons, Ltd and ERP Environment.

Kubota T.,Tokyo University of Science
Annals of Surgery | Year: 2017

OBJECTIVE:: To investigate the influence of donor age on recipient outcome after living-donor partial liver transplantation (LDLT). BACKGROUND:: Donor age is a well-known prognostic factor in deceased donor liver transplantation; however, its role in LDLT remains unclear. METHODS:: We retrospectively analyzed 315 consecutive cases of primary adult-to-adult LDLT in our center between April 2006 and March 2014. Recipients were divided into 5 groups according to the donor age: D-20s (n = 60); D-30s (n = 72); D-40s (n = 57); D-50s (n = 94); and D-60s (n = 32). The recipient survival and the association with various clinical factors were investigated. RESULTS:: Recipient survival proportions were significantly higher in D-20s compared with all the other groups (P = 0.008, < 0.001, < 0.001, and = 0.006, vs D-30s, -40s, -50s, and -60s, respectively), whereas there was no association between recipient survival and their own age. There are 3 typical relationships between donors and recipients in adult-to-adult LDLT: from child-to-parent, between spouses/siblings, and from parent-to-child. The overall survival in child-to-parent was significantly higher than in spouses/siblings (P = 0.002) and in parent-to-child (P = 0.005), despite significantly higher recipient age in child-to-parent [59 (42–69) years, P < 0.001]. Contrastingly, parent-to-child exhibited the lowest survival, despite the youngest recipient age [26 (20–43) years, P < 0.001]. In addition, younger donor age exhibited significantly better recipient survival both in hepatitis C virus-related and in non-hepatitis C virus diseases. Univariate and multivariate analyses both demonstrated that donor age and graft-type (right-sided livers) are independent prognostic factors for recipient survival. CONCLUSIONS:: Donor age is an independent, strong prognostic factor in adult-to-adult LDLT. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.

Zhanikeev M.,Tokyo University of Science
Mobile Information Systems | Year: 2017

The growing number of wireless devices nowadays often results in congestion of wireless channels. In research, this topic is referred to as networking in dense wireless spaces. The literature on the topic shows that the biggest problem is the high number of concurrent sessions to a wireless access point. The obvious solution is to reduce the number of concurrent sessions. This paper proposes a simple method called Bulk-n-Pick which minimizes the number of prolonged concurrent sessions by separating bulk from sync traffic. Aiming at educational applications, under the proposed design, web applications would distribute the main bulk of content once at the beginning of a class and then rely on small messages for real time sync traffic during the class. For realistic performance analysis, this paper first performs real-life experiments with various counts of wireless devices, bulk sizes, and levels of sync intensity. Based on the experiments, this paper shows that the proposed Bulk-n-Pick method outperforms the traditional design even when only two concurrent bulk sessions are allowed. The experiment shows that up to 10 concurrent bulk sessions are feasible in practice. Based on these results, a method for online performance optimization is proposed and validated in a trace-based emulation. © 2017 Marat Zhanikeev.

Yoshimura T.,Tokyo University of Science | Nawata H.,Chiyoda Corporation
Optics Communications | Year: 2017

The self-organized lightwave network (SOLNET) provides “optical solder,” which enables self-aligned optical couplings between misaligned optical devices with different core sizes. We propose a low-cost SOLNET formation method, in which write beams are generated within optical devices by excitation lights from outside. Simulations based on the finite-difference time-domain method reveal that the two-photon processes enhance optical-solder capabilities. In couplings between 600-nm-wide waveguides opposed with 32-μm distance a wide lateral misalignment tolerance of ~2 µm to maintain <1 dB loss at 650 nm in wavelength is obtained. The coupling loss at 1-μm lateral misalignment is 0.4 dB. In couplings between 3-μm-wide and 600-nm-wide waveguides, losses at 650 nm are 0.1 dB for no misalignments and 0.9 dB for 1-μm misalignment. These results suggest that SOLNETs provide optical solder with mode size converting functions. © 2016 The Authors

Ragusa M.A.,University of Catania | Tachikawa A.,Tokyo University of Science
AIP Conference Proceedings | Year: 2017

Our main goal is the study some regularity results where are considered estimates in Morrey spaces for the derivatives of local minimizers of variational integrals of the form A (u,Ω)= ∫ΩF(x,u,Du)dx where Ω is a bounded domain in rm and the integrand F have some different forms. © 2017 Author(s).

The association between plasma C-peptide concentration and prostate cancer is unclear. Inconsistency of results from previous studies motivates this study. Using the Japan Public Health Center-based Prospective study, 201 prostate cancer cases and 402 controls were matched by age, public health center area, residence, date and time of blood collection, and fasting duration before blood collection. Odds ratios (OR) and 95% confidence intervals (CIs) were estimated by conditional logistic regression models. Out of 201 cases, 144 were localized and 48 were advanced. The overall association between median plasma C-peptide concentration and prostate cancer was not significant (OR for the highest tertile=0.81, 95% CI: 0.43–1.56, P-trend=0.54). Although stratification of prostate cancer by stage indicated different effects of plasma C-peptide on localized and advanced cases, there was no association between plasma C-peptide concentration and advanced prostate cancer (OR=2.82, 95% CI: 0.30–26.36 for the highest category, P-trend=0.37) and localized cases (OR=0.49, 95% CI: 0.23–1.04 for the highest category, P-trend=0.06) for patients fasting at the time of blood collection. The association between plasma C-peptide concentration and prostate cancer risk differed by cancer stage. Differentiation of localized and advanced prostate cancer cases is crucial when investigating the association between plasma C-peptide concentration and the risk of prostate cancer. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.

IMAGE: The activated brain region differs according to the syllable when observing spatial-feature patterns. view more Credit: COPYRIGHT (C) TOYOHASHI UNIVERSITY OF TECHNOLOGY. ALL RIGHTS RESERVED. A research group, including Emeritus Professor Tsuneo Nitta, Professor Junsei Horikawa, and Assistant Professor Shunji Sugimoto at Toyohashi University of Technology along with Associate Professor Koichi Katsurada of Tokyo University of Science, has developed a technology that can recognize the numbers 0 to 9 with 90% accuracy using brain waves, or electroencephalogram (EEG), while uttering the numbers. Furthermore, the technology has also realized the recognition of 18 types of Japanese monosyllables from EEG signals with 60% accuracy, which shows the possibility of an EEG-activated typewriter in the near future. The details of this research will be presented at Interspeech 2017 held in Stockholm in August. http://www. The research group has collected EEG-data while uttering Japanese digits and monosyllables. Regarding these data, the group investigated digit and monosyllable recognition experiments. Up until now, speech-decoding from EEG signals has had difficulty in collecting enough data to allow the use of powerful algorithms based on 'deep learning' or other types of machine learning. The research group has developed a different research-framework that can achieve high performance with a small training data-set. The new framework is based on holistic pattern recognition using category theory, or composite mapping, in which a dual space and a tensor space including exterior algebra are introduced. In the experiment of spoken-digit recognition from EEG signals, 90% recognition accuracy was achieved. At the same time, 61% accuracy in 18 Japanese monosyllable recognition was achieved outperforming performance in previous research (humans have sufficient intelligibility of sentences with an 80% monosyllable recognition rate). Emeritus Professor Nitta and his group aim to develop a 'Brain Computer Interface' that recognizes utterances without voicing, or speech imagery. This technology may enable handicapped people, who have lost the ability of voice-communication, to obtain the ability once again. It is also expected that the technology would give a healthy person the most natural interface without any limitations as well. Furthermore, the research group plans to develop a device that can be easily operated with fewer electrodes and connected to smartphones within the next five years. This research was funded by the Ministry of Education, Culture, Sports, Science and Technology and the Japan Society for the Promotion of Science Research Grant 16K00251. We will hold a press conference on April 18 to present the details of this research at Toyohashi University of Technology.

Nance M.R.,University of Michigan | Kreutz B.,University of Illinois at Chicago | Tesmer V.M.,University of Michigan | Sterne-Marr R.,Siena College | And 3 more authors.
Structure | Year: 2013

The heterotrimeric G protein Gαq is a key regulator of blood pressure, and excess Gαq signaling leads to hypertension. A specific inhibitor of Gαq is the GTPase activating protein (GAP) known as regulator of G protein signaling 2 (RGS2). The molecular basis for how Gαq/11 subunits serve as substrates for RGS proteins and how RGS2 mandates its selectivity for Gαq is poorly understood. In crystal structures of the RGS2-Gαq complex, RGS2 docks to Gαq in a different orientation from that observed in RGS-Gαi/o complexes. Despite its unique pose, RGS2 maintains canonical interactions with the switch regions of Gαq in part because its α6 helix adopts a distinct conformation. We show that RGS2 forms extensive interactions with the α-helical domain of Gαq that contribute to binding affinity and GAP potency. RGS subfamilies that do not serve as GAPs for Gαq are unlikely to form analogous stabilizing interactions. © 2013 Elsevier Ltd. All rights reserved.

Kurusu T.,Tokyo University of Science | Kurusu T.,Tokyo University of Technology | Kuchitsu K.,Tokyo University of Science | Nakano M.,Tokyo Gakugei University | And 2 more authors.
Trends in Plant Science | Year: 2013

Mechanical stimuli generate Ca2+ signals and influence growth and development in plants. Recently, candidates for Ca2+-permeable mechanosensitive (MS) channels have been identified. These channels are thought to be responsible for sensing osmotic shock, touch, and gravity. One candidate is the MscS-like (MSL) protein family, a homolog of the typical bacterial MS channels. Some of the MSL proteins are localized to plastids to maintain their shape and size. Another candidate is the mid1-complementing activity (MCA) protein family, which is structurally unique to the plant kingdom. MCA proteins are localized in the plasma membrane and are suggested to be involved in mechanosensing and to be functionally related to reactive oxygen species (ROS) signaling. Here, we review their structural features and role in planta. © 2013 Elsevier Ltd.

De Felice A.,Tokyo University of Science | De Felice A.,Naresuan University | Kobayashi T.,Kyoto University | Tsujikawa S.,Tokyo University of Science
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2011

In the Horndeski's most general scalar-tensor theories the equations of scalar density perturbations are derived in the presence of non-relativistic matter minimally coupled to gravity. Under a quasi-static approximation on sub-horizon scales we obtain the effective gravitational coupling Geff associated with the growth rate of matter perturbations as well as the effective gravitational potential Geff relevant to the deviation of light rays. We then apply our formulas to a number of modified gravitational models of dark energy - such as those based on f(R) theories, Brans-Dicke theories, kinetic gravity braidings, covariant Galileons, and field derivative couplings with the Einstein tensor. Our results are useful to test the large-distance modification of gravity from the future high-precision observations of large-scale structure, weak lensing, and cosmic microwave background. © 2011 Elsevier B.V.

Taheri A.,University of Adelaide | Taheri A.,Tokyo University of Science | Tatsuoka F.,Tokyo University of Science
Soils and Foundations | Year: 2012

The peak compressive strengths at different confining pressures of cement-mixed gravel (CMG) that are very similar to those obtained by single-step loading (SL) drained triaxial compression (TC) tests using multiple specimens can be obtained by a multiple-step loading (ML) test using a single specimen. However, only the unload/reload stress-strain relations at different confining pressures (except for the primary loading pressure at the first step) can be obtained from an ML test, and the reloading relations become softer with the increases in negative irreversible axial strain increments that have taken place during the respective immediately preceding unloading regimes. This phenomenon is formulated by a unique empirical equation for the CMG tests. Undamaged reloading stress-strain curves (URCs) were inferred by removing the damage effects from measured reloading curves (MRCs) in the ML TC test based on this correlation. A method was developed within the framework of the proportional rule to infer primary loading curves (PLCs) at different confining pressures from the URCs and the PLC at the first step obtained from a given ML TC test. A procedure was formulated to modify the PLCs obtained by this procedure based on the PLCs measured at stresses exceeding the yield stress for large-scale yielding during reloading at different confining pressures in the ML test. This method was validated by comparing the PLCs obtained from the results of a pair of ML tests, increasing and decreasing the confining pressure, with those obtained from a set of SL TC tests at different confining pressures. © 2012 The Japanese Geotechnical Society.

Ozkan M.,University of Groningen | Pang Y.,Texas A&M University | Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We show that the universal α-attractor models of inflation can be realized by including an auxiliary vector field Aμ for the Starobinsky model with the Lagrangian f(R)=R+R2/(6M2). If the same procedure is applied to general modified f(R) theories in which the Ricci scalar R is replaced by R+AμAμ+β μAμ with constant β, we obtain the Brans-Dicke theory with a scalar potential and the Brans-Dicke parameter ωBD=β2/4. We also place observational constraints on inflationary models based on auxiliary vector modified f(R) theories from the latest Planck measurements of the cosmic microwave background anisotropies in both temperature and polarization. In the modified Starobinsky model, we find that the parameter β is constrained to be β<25 (68% confidence level) from the bounds of the scalar spectral index and the tensor-to-scalar ratio. © 2015 American Physical Society.

De Felice A.,Naresuan University | Tsujikawa S.,Tokyo University of Science
Journal of Cosmology and Astroparticle Physics | Year: 2012

The extended Galileon models possess tracker solutions with de Sitter attractors along which the dark energy equation of state is constant during the matter-dominated epoch, i.e. w DE = -1-s, where s is a positive constant. Even with this phantom equation of state there are viable parameter spaces in which the ghosts and Laplacian instabilities are absent. Using the observational data of the supernovae type Ia, the cosmic microwave background (CMB), and baryon acoustic oscillations, we place constraints on the tracker solutions at the background level and find that the parameter s is constrained to be s = 0.034 -0.034 +0.327 (95 % CL) in the flat Universe. In order to break the degeneracy between the models we also study the evolution of cosmological density perturbations relevant to the large-scale structure (LSS) and the Integrated-Sachs-Wolfe (ISW) effect in CMB. We show that, depending on the model parameters, the LSS and the ISW effect is either positively or negatively correlated. It is then possible to constrain viable parameter spaces further from the observational data of the ISW-LSS cross-correlation as well as from the matter power spectrum. © 2012 IOP Publishing Ltd and Sissa.

De Felice A.,Naresuan University | Tsujikawa S.,Tokyo University of Science
Journal of Cosmology and Astroparticle Physics | Year: 2012

In the Horndeski's most general scalar-tensor theories with second-order field equations, we derive the conditions for the avoidance of ghosts and Laplacian instabilities associated with scalar, tensor, and vector perturbations in the presence of two perfect fluids on the flat Friedmann-Lematre-Robertson- Walker (FLRW) background. Our general results are useful for the construction of theoretically consistent models of dark energy. We apply our formulas to extended Galileon models in which a tracker solution with an equation of state smaller than -1 is present. We clarify the allowed parameter space in which the ghosts and Laplacian instabilities are absent and we numerically confirm that such models are indeed cosmologically viable. © 2012 IOP Publishing Ltd and SISSA.

Ali A.,Saha Institute of Nuclear Physics | Gannouji R.,Tokyo University of Science | Hossain M.W.,Jamia Millia Islamia University | Sami M.,Jamia Millia Islamia University | Sami M.,Nagoya University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2012

In this Letter, we examine the cosmological viability of a light mass galileon field consistent with local gravity constraints. The minimal, L 3=□φ(∂ μφ) 2, massless galileon field requires an additional term in order to give rise to a viable ghost free late time acceleration of Universe. The desired cosmological dynamics can either be achieved by incorporating an additional terms in the action such as (L 4, L 5) - the higher order galileon Lagrangians or by considering a light mass field à la galileon field potential. We analyze the second possibility and find that: (1) The model produces a viable cosmology in the regime where the non-linear galileon field is subdominant, (2) the Vainshtein mechanism operates at small scales where the non-linear effects become important and contribution of the field potential ceases to be significant. Also the small mass of the field under consideration is protected against strong quantum corrections thereby providing quantum stability to the system. © 2012 Elsevier B.V.

Furusawa S.,Waseda University | Yamada S.,Waseda University | Suzuki H.,Tokyo University of Science
Astrophysical Journal | Year: 2011

We calculate a new equation of state for baryons at sub-nuclear densities meant for the use in core-collapse simulations of massive stars. The abundances of various nuclei are obtained together with the thermodynamic quantities. The formulation is the nuclear statistical equilibrium description and the liquid drop approximation of nuclei. The model free energy to minimize is calculated by relativistic mean field theory for nucleons and the mass formula for nuclei with atomic number up to 1000. We have also taken into account the pasta phase, thanks to which the transition to uniform nuclear matter in our equation of state (EOS) occurs in the conventional manner: nuclei are not dissociated into nucleons but survive right up to the transition to uniform nuclear matter. We find that the free energy and other thermodynamical quantities are not very different from those given in the H. Shen's EOS, one of the standard EOSs that adopt the single nucleus approximation. On the other hand, the average mass is systematically different, which may have an important ramification to the rates of electron captures and coherent neutrino scatterings on nuclei in supernova cores. It is also interesting that the root mean square of the mass number is not very different from the average mass number, since the former is important for the evaluation of coherent scattering rates on nuclei but has been unavailable so far. The EOS table is currently under construction, which will include the weak interaction rates. © 2011. The American Astronomical Society. All rights reserved.

Liu X.,Shanghai University | Liu Z.-P.,CAS Shanghai Institutes for Biological Sciences | Zhao X.-M.,Shanghai University | Chen L.,Shanghai University | And 2 more authors.
Journal of the American Medical Informatics Association | Year: 2012

Objective: A complex disease is generally caused by the mutation of multiple genes or by the dysfunction of multiple biological processes. Systematic identification of causal disease genes and module biomarkers can provide insights into the mechanisms underlying complex diseases, and help develop efficient therapies or effective drugs. Materials and Methods: In this paper, we present a novel approach to predict disease genes and identify dysfunctional networks or modules, based on the analysis of differential interactions between disease and control samples, in contrast to the analysis of differential gene or protein expressions widely adopted in existing methods. Results and Discussion: As an example, we applied our method to the study of three-stage microarray data for gastric cancer. We identified network modules or module biomarkers that include a set of genes related to gastric cancer, implying the predictive power of our method. The results on holdout validation data sets show that our identified module can serve as an effective module biomarker for accurately detecting or diagnosing gastric cancer, thereby validating the efficiency of our method. Conclusion: We proposed a new approach to detect module biomarkers for diseases, and the results on gastric cancer demonstrated that the differential interactions are useful to detect dysfunctional modules in the molecular interaction network, which in turn can be used as robust module biomarkers.

Tsujikawa S.,Tokyo University of Science | Ohashi J.,Tokyo University of Science | Kuroyanagi S.,Tokyo University of Science | De Felice A.,Naresuan University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We place observational constraints on slow-variation single-field inflationary models by carrying out the cosmological Monte Carlo simulation with the recent data of Planck combined with the WMAP large-angle polarization, baryon acoustic oscillations, and Atacama Cosmology Telescope/South Pole Telescope temperature data. Our analysis covers a wide variety of models with second-order equations of motion, including potential-driven slow-roll inflation, nonminimally coupled models, running kinetic couplings, Brans-Dicke theories, potential-driven Galileon inflation, field-derivative couplings to the Einstein tensor, and k-inflation. In the presence of running kinetic exponential couplings, covariant Galileon terms, and field-derivative couplings, the tensor-to-scalar ratio of the self-coupling potential V(φ)= λφ4/4 gets smaller relative to that in standard slow-roll inflation, but the models lie outside the 1σ observational contour. We also show that k-inflation models can be tightly constrained by adding the bounds from the scalar non-Gaussianities. The small-field inflationary models with asymptotic flat Einstein-frame potentials in the regime φ Mpl generally fit the data very well. These include the models such as Kähler-moduli inflation, nonminimally coupled Higgs inflation, and inflation in Brans-Dicke theories in the presence of the potential V(φ)=3M2(φ-Mpl)2/4 with the Brans-Dicke parameter ωBD O(1) (which covers the Starobinsky's model f(R)=R+R2/(6M2) as a special case). © 2013 American Physical Society.

Qiu X.,Tokyo University of Science | Miyauchi M.,Japan National Institute of Advanced Industrial Science and Technology | Yu H.,Tokyo University of Science | Irie H.,Yamanashi University | And 2 more authors.
Journal of the American Chemical Society | Year: 2010

Band-gap narrowing is generally considered to be a primary method in the design of visible-light-active photocatalysts because it can decrease the photo threshold to lower energies. However, controlling the valence band by up-shifting the top of the band or inducing localized levels above the band results in quantum efficiencies under visible light much lower than those under UV irradiation (such as those reported for N-doped TiO2: Science 2001, 293, 269. J. Phys. Chem. B 2003, 107, 5483). Herein, we report a systematic study on a novel, visible-light-driven photocatalyst based on conduction band control and surface ion modification. Cu(II)-(Sr 1-yNay)(Ti1-xMox)O3 photocatalysts were prepared by a soft chemical method in combination with an impregnation technique. It is found that Mo6+ as well as Na + doping in the SrTiO3 can lower the bottom of the conduction band and effectively extend the absorption edge to the visible light region. The Cu(II) clusters grafted on the surface act as a co-catalyst to efficiently reduce the oxygen molecules, thus consuming the excited electrons. Consequently, photocatalytic decomposition of gaseous 2-propanol into CO 2 is achieved, that is, CH3CHOHCH3 + 9/2O2 → 3CO2 + H2O. For Cu(II)-(Sr1-yNay)(Ti1-xMo x)O3 at x = 2.0% under visible light irradiation, the maximum CO2 generation rate can reach 0.148 μmol/h; the quantum efficiency under visible light is calculated to be 14.5%, while it is 10% under UV light irradiation. Our results suggest that high visible light photocatalytic efficiency can be achieved by combining conduction band control and surface ion modification, which provides a new approach for rational design and development of high-performance photocatalysts. © 2010 American Chemical Society.

Chiba T.,Nihon University | De Felice A.,Naresuan University | Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

For two types of quintessence models having thawing and tracking properties, there exist analytic solutions for the dark energy equation of state w expressed in terms of several free parameters. We put observational bounds on the parameters in such scenarios by using the recent type Ia supernovae, cosmic microwave background, and baryon acoustic oscillations data. The observational constraints are quite different depending on whether or not the recent baryon acoustic oscillations data from BOSS are taken into account. With the BOSS data the upper bounds of today's values of w (=w0) in thawing models is very close to -1, whereas without this data the values of w0 away from -1 can still be allowed. The tracker equation of state w(0) during the matter era is constrained to be w(0)<-0.949 at 95% C.L. even without the BOSS data, so that the tracker models with w away from -1 are severely disfavored. We also study observational constraints on scaling models in which w starts to evolve from 0 in the deep matter era and show that the transition to the equation of state close to w=-1 needs to occur at an early cosmological epoch. In the three classes of quintessence models studied in this paper, the past evolution of the Hubble parameters in the best-fit models shows only less than a 2.5% difference compared to ΛCDM. © 2013 American Physical Society.

Yu H.,Tokyo University of Science | Yu H.,Yamanashi University | Irie H.,Tokyo University of Science | Irie H.,Yamanashi University | And 2 more authors.
Journal of the American Chemical Society | Year: 2010

Through the use of a strategy that involves narrowing the TiO2 band gap by shifting its conduction band positively and utilizing the catalytic activity of photoproduced Cu(I) for oxygen reduction, a novel visible-light-sensitive TiO2 photocatalyst, Cu(II)-grafted Ti 1-3xWxGa2xO2, was designed and synthesized. The Cu(II)/Ti1-3xWxGa2xO 2 photocatalyst produced high activity under visible-light irradiation. In fact, it decomposed 2-propanol to CO2 via acetone under visible light (>400 nm) with a high quantum efficiency of 13%. The turnover number for this reaction exceeded 22, indicating that it functioned catalytically. © 2010 American Chemical Society.

Furusawa S.,Waseda University | Yamada S.,Waseda University | Suzuki H.,Tokyo University of Science
Astrophysical Journal | Year: 2013

We construct new equations of state for baryons at subnuclear densities for the use in core-collapse simulations of massive stars. The abundance of various nuclei is obtained together with thermodynamic quantities. A model free energy is constructed, based on the relativistic mean field theory for nucleons and the mass formula for nuclei with the proton number up to ∼1000. The formulation is an extension of the previous model, in which we adopted the liquid drop model to all nuclei under the nuclear statistical equilibrium. We reformulate the new liquid drop model so that the temperature dependences of bulk energies could be taken into account. Furthermore, we extend the region in the nuclear chart, in which shell effects are included, by using theoretical mass data in addition to experimental ones. We also adopt a quantum-theoretical mass evaluation of light nuclei, which incorporates the Pauli- and self-energy shifts that are not included in the ordinary liquid drop model. The pasta phases for heavy nuclei are taken into account in the same way as in the previous model. We find that the abundances of heavy nuclei are modified by the shell effects of nuclei and temperature dependence of bulk energies. These changes may have an important effect on the rates of electron captures and coherent neutrino scatterings on nuclei in supernova cores. The abundances of light nuclei are also modified by the new mass evaluation, which may affect the heating and cooling rates of supernova cores and shocked envelopes. © 2013. The American Astronomical Society. All rights reserved.

Yui H.,Tokyo University of Science | Konno K.,Tokyo University of Science
Journal of Physical Chemistry C | Year: 2011

High-capacity SiO powder composite electrodes for rechargeable lithium-ion batteries are prepared with different polymer binders of poly(acrylic acid) (PAA), poly(vinyl alcohol) (PVA), sodium carboxymethyl cellulose (CMCNa), and conventional poly(vinylidene fluoride) (PVdF). Electrode performance of the SiO composites highly depends on selection of binders, and their electrochemical reversibility is drastically improved by using PAA as the binder in comparison to the PVdF, CMCNa, and PVA binders. Coulombic efficiency at the initial cycle is improved for the SiO-PAA composite electrode, and the reversible capacity reaches 700-750 mAh g-1 for continuous fifty cycling test at a rate of 100 mA g-1. The improvement mechanism of SiO-PAA composite electrode is characterized by X-ray diffraction, electron microscopy, X-ray photoelectron spectroscopy, infrared spectroscopy, self-discharge test, and adhesive strength test. Amorphous PAA polymer not only tightly binds but also covers the individual SiO particles. Moreover, the PAA binder suppresses swelling of the composite electrode with the electrolyte solution compared to the PVdF binder. Through-thickness electric resistance of the PAA composite electrode is much lower than that of the PVdF when it is wet with the electrolyte. It is proposed that these characters of the PAA binder effectively suppress isolation of the SiO powders in the composite electrode associated with the large volume expansion/shrinkage during the lithiation/delithiation processes. © 2011 American Chemical Society.

Manzhos S.,National University of Singapore | Segawa H.,Tokyo University of Science | Yamashita K.,University of Tokyo
Physical Chemistry Chemical Physics | Year: 2013

We study the effect of nuclear motions at different temperatures, including the effect of a dye molecule's orientation with respect to the oxide surface, on factors determining the performance of dye sensitized solar cells: light absorption, electron injection, and back-donation. We perform ab initio molecular dynamics simulations of aminophenyl acid dyes NK1 and NK7, differing by the electron donating group, in a vacuum and adsorbed in mono- and bi-dentate modes on a dry and a water-covered anatase (101) surface of TiO2, at 300 and 350 K. Nuclear vibrations and an increase of temperature cause a red shift in the absorption spectra of free dyes. This effect is preserved in dyes on dry TiO2 but largely disappears in the presence of water. Averaged over nuclear vibrations, the driving force to injection, ΔG, differs from the static estimate. It depends on the adsorption mode and the presence of H2O but is almost the same for 300 and 350 K. Recombination to the dye cation is expected to be much enhanced by the approach of the dye oxidation equivalent hole to the surface during dye wagging around TiO2. This effect is somewhat mitigated by the co-adsorbed water. The dynamics of ΔG(t) are explained by uncorrelated evolution of the energies of the dye excited state and the conduction band minimum of the oxide due to their respective vibrations, and are almost independent of dye orientation. It may therefore be possible to independently control the conditions of recombination and of injection. © the Owner Societies 2013.

Gannouji R.,Tokyo University of Science | Gannouji R.,University of Oslo | Sami M.,Jamia Millia Islamia University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We derive field equations of Gauss-Bonnet gravity in four dimensions after dimensional reduction of the action and demonstrate that in this scenario the Vainshtein mechanism operates in the flat spherically symmetric background. We show that inside this Vainshtein sphere the fifth force is negligibly small compared to the gravitational force. We also investigate the stability of the spherically symmetric solution, and clarify the vocabulary used in the literature about the hyperbolicity of the equation and the ghost-Laplacian stability conditions. We find superluminal behavior of the perturbation of the field in the radial direction. However, because of the presence of the nonlinear terms, the structure of the space-time is modified and as a result the field does not propagate in the Minkowski metric but rather in an "aether" composed of the scalar field π(r). We thereby demonstrate that the superluminal behavior does not create time paradoxes thanks to the absence of causal closed curves. We also derive the stability conditions for a Friedmann universe in context with scalar and tensor perturbations and we study the cosmology of the model. © 2012 American Physical Society.

De Felice A.,Naresuan University | Kase R.,Tokyo University of Science | Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

In second-order scalar-tensor theories we study how the Vainshtein mechanism works in a spherically symmetric background with a matter source. In the presence of the field coupling F=e -2Q with the Ricci scalar R we generally derive the Vainshtein radius within which the general relativistic behavior is recovered even for the coupling Q of the order of unity. Our analysis covers the models such as the extended Galileon and Brans-Dicke theories with a dilatonic field self-interaction. We show that, if these models are responsible for the cosmic acceleration today, the corrections to gravitational potentials are generally small enough to be compatible with local gravity constraints. © 2012 American Physical Society.

De Felice A.,Naresuan University | Tsujikawa S.,Tokyo University of Science
Journal of Cosmology and Astroparticle Physics | Year: 2013

In the Horndeski's most general scalar-tensor theories, we derive the three-point correlation function of scalar non-Gaussianities generated during single-field inflation in the presence of slow-variation corrections to the leading-order term. Unlike previous works, the resulting bispectrum is valid for any shape of non-Gaussianities. In the squeezed limit, for example, this gives rise to the same consistency relation as that derived by Maldacena in standard single-field slow-roll inflation. We estimate the shape close to the squeezed one at which the effect of the term inversely proportional to the scalar propagation speed squared begins to contribute to the bispectrum. We also show that the leading-order bispectrum can be expressed by the linear combination of two convenient bases whose shapes are highly correlated with equilateral and orthogonal types respectively. We present concrete models in which the orthogonal and enfolded shapes can dominate over the equilateral one.© 2013 IOP Publishing Ltd and Sissa Medialab srl.

Isoda K.,Tokyo University of Science | Abe T.,Tokyo University of Science | Funahashi M.,Kagawa University | Tadokoro M.,Tokyo University of Science
Chemistry - A European Journal | Year: 2014

The preparation of two liquid crystals composed of a redox-active tetraazanaphthacene (TANC) framework is reported. The materials form smectic A (SmA) thin-film liquid-crystalline (LC) phases over a wide temperature range. Cyclic voltammetry analysis revealed that LC TANCs behave as organic electron acceptors. The electron mobilities of the thin films were determined by time- of-flight (TOF) measurements, which are the order of 10-4cm 2V-1s-1 in the SmA LC phase. This value is two orders of magnitude larger than those of amorphous organic semiconductors. To the best of our knowledge, very few reports exist on the electron-transporting behaviors of LC N-heteroacene semiconductors. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hayashi Y.,Tokyo University of Science | Suga H.,Tokyo University of Science
Accounts of Chemical Research | Year: 2011

Transfer RNA (tRNA) is an essential component of the cell's translation apparatus. These RNA strands contain the anticodon for a given amino acid, and when "charged" with that amino acid are termed aminoacyl-tRNA. Aminoacylation, which occurs exclusively at one of the 3′-terminal hydroxyl groups of tRNA, is catalyzed by a family of enzymes called aminoacyl-tRNA synthetases (ARSs). In a primitive translation system, before the advent of sophisticated protein-based enzymes, this chemical event could conceivably have been catalyzed solely by RNA enzymes. Given the evolutionary implications, our group attempted in vitro selection of artificial ARS-like ribozymes, successfully uncovering a functional ribozyme (r24) from an RNA pool of random sequences attached to the 5′-leader region of tRNA. This ribozyme preferentially charges aromatic amino acids (such as phenylalanine) activated with cyanomethyl ester (CME) onto specific kinds of tRNA.During the course of our studies, we became interested in developing a versatile, rather than a specific, aminoacylation catalyst. Such a ribozyme could facilitate the preparation of intentionally misacylated tRNAs and thus serve a convenient tool for manipulating the genetic code. On the basis of biochemical studies of r24, we constructed a truncated version of r24 (r24mini) that was 57 nucleotides long. This r24mini was then further shortened to 45 nucleotides. This ribozyme could charge various tRNAs through very simple three-base-pair interactions between the ribozyme's 3′-end and the tRNA's 3′-end. We termed this ribozyme a "flexizyme" (Fx3 for this particular construct) owing to its flexibility in addressing tRNAs.To devise an even more flexible tool for tRNA acylation, we attempted to eliminate the amino acid specificity from Fx3. This attempt yielded an Fx3 variant, termed dFx, which accepts amino acid substrates having 3,5-dinitrobenzyl ester instead of CME as a leaving group. Similar selection attempts with the original phenylalanine-CME and a substrate activated by (2-aminoethyl)amidocarboxybenzyl thioester yielded the variants eFx and aFx (e and a denote enhanced and amino, respectively). In this Account, we describe the history and development of these flexizymes and their appropriate substrates, which provide a versatile and easy-to-use tRNA acylation system. Their use permits the synthesis of a wide array of acyl-tRNAs charged with artificial amino and hydroxy acids.In parallel to these efforts, we initiated a crystallization study of Fx3 covalently conjugated to a microhelix RNA, which is an analogue of tRNA. The X-ray crystal structure, solved as a co-complex with phenylalanine ethyl ester and U1A-binding protein, revealed the structural basis of this enzyme. Most importantly, many biochemical observations were consistent with the crystal structure. Along with the predicted three regular-helix regions, however, the flexizyme has a unique irregular helix that was unexpected. This irregular helix constitutes a recognition pocket for the aromatic ring of the amino acid side chain and precisely brings the carbonyl group to the 3′-hydroxyl group of the tRNA 3′-end. This study has clearly defined the molecular interactions between Fx3, tRNA, and the amino acid substrate, revealing the fundamental basis of this unique catalytic system. © 2011 American Chemical Society.

Kirihara A.,NEC Corp | Uchida K.-I.,Tohoku University | Uchida K.-I.,Japan Science and Technology Agency | Kajiwara Y.,Tohoku University | And 9 more authors.
Nature Materials | Year: 2012

Energy harvesting technologies, which generate electricity from environmental energy, have been attracting great interest because of their potential to power ubiquitously deployed sensor networks and mobile electronics. Of these technologies, thermoelectric (TE) conversion is a particularly promising candidate, because it can directly generate electricity from the thermal energy that is available in various places. Here we show a novel TE concept based on the spin Seebeck effect, called 'spin-thermoelectric (STE) coating', which is characterized by a simple film structure, convenient scaling capability, and easy fabrication. The STE coating, with a 60-nm-thick bismuth-substituted yttrium iron garnet (Bi:YIG) film, is applied by means of a highly efficient process on a non-magnetic substrate. Notably, spin-current-driven TE conversion is successfully demonstrated under a temperature gradient perpendicular to such an ultrathin STE-coating layer (amounting to only 0.01% of the total sample thickness). We also show that the STE coating is applicable even on glass surfaces with amorphous structures. Such a versatile implementation of the TE function may pave the way for novel applications making full use of omnipresent heat. © 2012 Macmillan Publishers Limited. All rights reserved.

Yabuuchi N.,Tokyo University of Science | Kajiyama M.,Tokyo University of Science | Iwatate J.,Tokyo University of Science | Usui R.,Tokyo University of Science | And 2 more authors.
Nature Materials | Year: 2012

Rechargeable lithium batteries have risen to prominence as key devices for green and sustainable energy development. Electric vehicles, which are not equipped with an internal combustion engine, have been launched in the market. Manganese-and iron-based positive-electrode materials, such as LiMn 2 O 4 and LiFePO 4, are used in large-scale batteries for electric vehicles. Manganese and iron are abundant elements in the Earth's crust, but lithium is not. In contrast to lithium, sodium is an attractive charge carrier on the basis of elemental abundance. Recently, some layered materials, where sodium can be electrochemically and reversibly extracted/inserted, have been reported. However, their reversible capacity is typically limited to 100mAhg-1. Herein, we report a new electrode material, P2-Na 2/3 [Fe 1/2 Mn 1/2[O 2, that delivers 190mAhg -1 of reversible capacity in the sodium cells with the electrochemically active Fe 3+/Fe 4+ redox. These results will contribute to the development of rechargeable batteries from the earth-abundant elements operable at room temperature. © 2012 Macmillan Publishers Limited. All rights reserved.

Nakazato K.,Kyoto University | Suzuki H.,Tokyo University of Science | Yamada S.,Waseda University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

The detection of neutrinos from massive stellar collapses can teach us a great deal not only about source objects but also about microphysics working deep inside them. In this study we discuss quantitatively the possibility to extract information on the properties of dense and hot hadronic matter from neutrino signals coming out of black-hole-forming collapses of nonrotational massive stars. Based on our detailed numerical simulations we evaluate the event numbers for SuperKamiokande, with neutrino oscillations fully taken into account. We demonstrate that the event numbers from a Galactic event are large enough not only to detect but also to distinguish one hadronic equation of state from another by our statistical method, assuming the same progenitor model and nonrotation. This means that the massive stellar collapse can be a unique probe into hadron physics and will be a promising target of the nascent neutrino astronomy. © 2010 The American Physical Society.

Nakazato K.,Tokyo University of Science | Suzuki H.,Tokyo University of Science | Totani T.,Kyoto University | Umeda H.,University of Tokyo | Yamada S.,Waseda University
Astrophysical Journal, Supplement Series | Year: 2013

We present a new series of supernova neutrino light curves and spectra calculated by numerical simulations for a variety of progenitor stellar masses (13-50 M⊙) and metallicities (Z = 0.02 and 0.004), which would be useful for a broad range of supernova neutrino studies, e.g., simulations of future neutrino burst detection by underground detectors or theoretical predictions for the relic supernova neutrino background. To follow the evolution from the onset of collapse to 20 s after the core bounce, we combine the results of neutrino-radiation hydrodynamic simulations for the early phase and quasi-static evolutionary calculations of neutrino diffusion for the late phase, with different values of shock revival time as a parameter that should depend on the still unknown explosion mechanism. We describe the calculation methods and basic results, including the dependence on progenitor models and the shock revival time. The neutrino data are publicly available electronically. © 2013. The American Astronomical Society. All rights reserved.

Komatsu N.,University of Tokyo | Komatsu N.,Japan Science and Technology Agency | Okamoto K.,University of Tokyo | Okamoto K.,Japan Science and Technology Agency | And 13 more authors.
Nature Medicine | Year: 2014

Autoimmune diseases often result from an imbalance between regulatory T (T reg) cells and interleukin-17 (IL-17)-producing T helper (T H 17) cells; the origin of the latter cells remains largely unknown. Foxp3 is indispensable for the suppressive function of T reg cells, but the stability of Foxp3 has been under debate. Here we show that T H 17 cells originating from Foxp3 + T cells have a key role in the pathogenesis of autoimmune arthritis. Under arthritic conditions, CD25 lo Foxp3 + CD4 + T cells lose Foxp3 expression (herein called exFoxp3 cells) and undergo transdifferentiation into T H 17 cells. Fate mapping analysis showed that IL-17-expressing exFoxp3 T (exFoxp3 T H 17) cells accumulated in inflamed joints. The conversion of Foxp3 + CD4 + T cells to T H 17 cells was mediated by synovial fibroblast-derived IL-6. These exFoxp3 T H 17 cells were more potent osteoclastogenic T cells than were naive CD4 + T cell-derived T H 17 cells. Notably, exFoxp3 T H 17 cells were characterized by the expression of Sox4, chemokine (C-C motif) receptor 6 (CCR6), chemokine (C-C motif) ligand 20 (CCL20), IL-23 receptor (IL-23R) and receptor activator of NF-κB ligand (RANKL, also called TNFSF11). Adoptive transfer of autoreactive, antigen-experienced CD25 lo Foxp3 + CD4 + T cells into mice followed by secondary immunization with collagen accelerated the onset and increased the severity of arthritis and was associated with the loss of Foxp3 expression in the majority of transferred T cells. We observed IL-17 + Foxp3 + T cells in the synovium of subjects with active rheumatoid arthritis (RA), which suggests that plastic Foxp3 + T cells contribute to the pathogenesis of RA. These findings establish the pathological importance of Foxp3 instability in the generation of pathogenic T H 17 cells in autoimmunity.

Liu X.,National University of Singapore | Zhang W.,National University of Singapore | Uchida S.,Tokyo University of Science | Cai L.,National University of Singapore | And 2 more authors.
Advanced Materials | Year: 2010

(Figure Presented) In situ polymerized PEDOT is used as hole-transporting material to fabricate dye-sensitized solar cells (DSSCs) with an average efficiency of 6.1% (under 100 mW cm-2 AM 1.5 illumination) using organic D149 dye as the sensitizer. By comparing with Z907-based devices, the excellent light response of D149-sensitized DSSCs is attributed to the broad light absorption, low photoelectron recombination, and good polymer penetration © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tokyo University of Science, Saga University and Kagawa University | Date: 2014-04-09

An activity enhancer for an anticancer agent includes, as an active ingredient, a D-form amino acid residue-containing FNIII14 polypeptide, the D-form amino acid residue-containing FNIII14 being a polypeptide FNIII14 represented by SEQ ID NO: 1 in which at least one of amino acid residues at positions 1 to 13 is a D-form amino acid residue. An anticancer composition includes the activity enhancer for an anticancer agent and an anticancer agent.

Canon Kabushiki Kaisha, Kyoto University, Tokyo Institute of Technology, Tokyo University of Science, Yamanashi University, Japan National Institute of Advanced Industrial Science, Technology and Sophia University | Date: 2013-08-05

Provided is a piezoelectric material excellent in piezoelectricity. The piezoelectric material includes a perovskite-type complex oxide represented by the following General Formula (1). A(Zn_(x)Ti_((1-x)))_(y)M_((1-y))O_(3)(1) wherein A represents at least one kind of element containing at least a Bi element and selected from a trivalent metal element; M represents at least one kind of element of Fe, Al, Sc, Mn, Y, Ga, and Yb; x represents a numerical value satisfying 0.4x0.6; and y represents a numerical value satisfying 0.1y0.9.

Baldwin M.W.,Harvard University | Toda Y.,Tokyo University of Science | Nakagita T.,Tokyo University of Science | O'Connell M.J.,Dublin City University | And 4 more authors.
Science | Year: 2014

Sensory systems define an animal's capacity for perception and can evolve to promote survival in new environmental niches. We have uncovered a noncanonical mechanism for sweet taste perception that evolved in hummingbirds since their divergence from insectivorous swifts, their closest relatives. We observed the widespread absence in birds of an essential subunit (T1R2) of the only known vertebrate sweet receptor, raising questions about how specialized nectar feeders such as hummingbirds sense sugars. Receptor expression studies revealed that the ancestral umami receptor (the T1R1-T1R3 heterodimer) was repurposed in hummingbirds to function as a carbohydrate receptor. Furthermore, the molecular recognition properties of T1R1-T1R3 guided taste behavior in captive and wild hummingbirds. We propose that changing taste receptor function enabled hummingbirds to perceive and use nectar, facilitating the massive radiation of hummingbird species.

Miyake Y.,Kyushu University | Toyonaga K.,Kyushu University | Mori D.,Kyushu University | Kakuta S.,Japan Institute for Molecular Science | And 9 more authors.
Immunity | Year: 2013

Cord factor, also called trehalose-6,6'-dimycolate (TDM), is a potent mycobacterial adjuvant. We herein report that the C-type lectin MCL (also called Clec4d) is a TDM receptor that is likely to arise from gene duplication of Mincle (also called Clec4e). Mincle isknown to be an inducible receptor recognizing TDM, whereas MCL was constitutively expressed in myeloid cells. To examine the contribution of MCL in response to TDM adjuvant, we generated MCL-deficient mice. TDM promoted innate immune responses, such as granuloma formation, which was severely impaired in MCL-deficient mice. TDM-induced acquired immune responses, such as experimental autoimmune encephalomyelitis (EAE), was almost completely dependent on MCL, but not Mincle. Furthermore, by generating Clec4egfp reporter mice, we found that MCL was also crucial for driving Mincle induction upon TDM stimulation. These results suggest that MCL is an FcRγ-coupled activating receptor that mediates the adjuvanticity ofTDM. •MCL is an ITAM-coupled TDM receptor that arises from gene duplication of Mincle•Innate and acquired immunity induced by TDM are impaired in MCL-deficient mice•MCL drives Mincle expression in dendritic cells upon TDM stimulation•MCL, but not Mincle, is critically involved in EAE induced by TDM adjuvant. © 2013 Elsevier Inc.

Tanaka K.-I.,University of Electro - Communications | Furuta T.,Tokyo University of Science
Geographical Analysis | Year: 2012

This article presents a hierarchical flow capturing location problem (HFCLP) and proposes an effective Lagrangian heuristic solution method. The original flow capturing location problem (FCLP) aims to locate a given number of facilities on a network to maximize the total flow that can be serviced at facilities along their preplanned routes, such as daily commute to work. We extend the original model to allow a decision maker to select the size of facilities among m different size alternatives. Larger facilities are assumed to be more attractive and, therefore, can attract more customers, but they cost more to construct than smaller ones. Customers deviate from their preplanned routes to access a facility's service when the size of the facility is sufficiently large. The degree of deviation from the original path is measured by the additional distance customers have to go to access facilities, and the acceptable deviation distance becomes larger as the size of a facility increases. This article presents a new problem in which the number of facilities of each size and their locations are simultaneously determined so as to capture as much flow as possible within the total budget available for locating all facilities. We present an integer programming formulation of the problem and devise a Lagrangian relaxation solution method. The proposed algorithm is tested using road networks with 300 and 500 nodes. The results show that the method produces high-quality solutions in a fairly short time. © 2012 The Ohio State University.

Ikeda H.,Rikkyo University | Watanabe K.,Tokyo University of Science | Cavanagh P.,University of Paris Descartes
Journal of Vision | Year: 2013

It is difficult to identify a target in the peripheral visual field when it is flanked by distractors. In the present study, we investigated this "crowding" effect for biological motion stimuli. Three walking biological motion stimuli were presented horizontally in the periphery with various distances between them, and observers reported the walking direction of the central figure. When the inter-walker distance was small, discriminating the direction became difficult. Moreover, the reported direction for the central target was not simply noisier, but reflected a degree of pooling of the three directions from the target and two flankers. However, when the two flanking distractors were scrambled walking biological motion stimuli, crowding was not seen. This result suggests that the crowding of biological motion stimuli occurs at a high-level of motion perception. © 2013 ARVO.

Yoshida H.,Tokyo University of Science | Yabuuchi N.,Tokyo University of Science | Kubota K.,Tokyo University of Science | Ikeuchi I.,Tokyo University of Science | And 3 more authors.
Chemical Communications | Year: 2014

New electrode materials of layered oxides, Na2/3Ni 1/3Mn2/3-xTixO2 (0 ≤ x ≤ 2/3), are successfully synthesized, and their electrochemical performance is examined in aprotic Na cells. A Na//Na2/3Ni1/3Mn 1/2Ti1/6O2 cell delivers 127 mA h g -1 of reversible capacity and the average voltage reaches 3.7 V at first discharge with good capacity retention. This journal is © the Partner Organisations 2014.

Soai K.,Tokyo University of Science | Kawasaki T.,Tokyo University of Science | Kawasaki T.,University of Fukui | Matsumoto A.,Tokyo University of Science
Accounts of Chemical Research | Year: 2014

(Figure Presented) Amplification of enantiomeric excess (ee) is a key feature for the chemical evolution of biological homochirality from the origin of chirality. We describe the amplification of ee in the asymmetric autocatalysis of 5-pyrimidyl alkanols in the reaction between diisopropylzinc (i-Pr2Zn) and pyrimidine-5-carbaldehydes. During the reaction, an extremely low ee (ca. 0.00005% ee) can be amplified to >99.5% ee, and therefore, the initial slightly major enantiomer is automultiplied by a factor of ca. 630000, while the initial slightly minor enantiomer is automultiplied by a factor of less than 1000. In addition, pyrimidyl alkanols with various substituents at the 2-position of the pyrimidine ring, 3-quinolyl alkanol, 5-carbamoyl-3-pyridyl alkanol, and large multifunctionalized pyrimidyl alkanols also act as highly efficient asymmetric autocatalysts in the addition of i-Pr2Zn to the corresponding aldehydes. The asymmetric autocatalysis of pyrimidyl alkanol can discriminate the chirality of various compounds. Chiral substances such as alcohols, amino acids, hydrocarbons, metal complexes, and heterogeneous chiral materials can act as chiral triggers for asymmetric autocatalysis to afford pyrimidyl alkanols with the corresponding absolute configuration of the initiator. This recognition ability of chiral compounds is extremely high, and chiral discrimination of a cryptochiral quaternary saturated hydrocarbon was established by applying asymmetric autocatalysis. By using the large ampli fication effect of the asymmetric autocatalysis, we can link various proposed origins of chirality with highly enantioenriched organic compounds in conjunction with asymmetric autocatalysis. Thus, a statistical fluctuation in ee of racemic compounds can be amplified to high ee by using asymmetric autocatalysis. Enantiomeric imbalance induced by irradiation of circularly polarized light can affect the enantioselectivity of asymmetric autocatalysis. The asymmetric autocatalysis was also triggered by the morphology of inorganic chiral crystals such as quartz, sodium chlorate, and cinnabar. Chiral organic crystals of achiral compounds also act as chiral initiators, and during the study of a crystal of cytosine, enantioselective chiral crystal phase transformation of the cytosine crystal was achieved by removal of the water of crystallization in an achiral monohydrate crystal. Enantioselective C-C bond formation was realized on the surfaces of achiral single crystals based on the oriented prochirality of achiral aldehydes. Furthermore, asymmetric autocatalysis of pyrimidyl alkanols is a highly sensitive reaction that can recognize and amplify the significantly small effect of a chiral compound arising solely from isotope substitution of hydrogen, carbon, and oxygen (D/H, 13C/12C, and 18O/16O). These examples show that asymmetric autocatalysis with an amplification of chirality is a powerful tool for correlating the origin of chirality with highly enantioenriched organic compounds. Asymmetric autocatalysis using two β-amino alcohols reveals a reversal of enantioselectivity in the addition of i-Pr2Zn to aldehyde and is one approach toward understanding the mechanism of asymmetric dialkylzinc addition, where heteroaggregates act as the catalytic species. © 2014 American Chemical Society.

Soai K.,Tokyo University of Science | Kawasaki T.,Tokyo University of Science | Kawasaki T.,University of Fukui | Matsumoto A.,Tokyo University of Science
Chemical Record | Year: 2014

Pyrimidyl alkanol was found to act as an asymmetric autocatalyst in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde. Asymmetric autocatalysis of 2-alkynylpyrimidyl alkanol with an extremely low enantiomeric excess (ca. 0.00005% ee) exhibits enormous asymmetric amplification to afford the same compound with >99.5% ee. This asymmetric autocatalysis with amplification of ee has been employed to examine the validity of proposed theories of the origins of homochirality. Circularly polarized light, quartz, sodium chlorate, cinnabar, chiral organic crystals and spontaneous absolute asymmetric synthesis were considered as possible candidates for the origin of chirality; each could act as a chiral source in asymmetric autocatalysis. Asymmetric autocatalysis can discriminate the isotope chirality arising from the small difference between carbon (carbon-13/carbon-12) and hydrogen (D/H) isotopes. Cryptochiral compounds were also discriminated by asymmetric autocatalysis. Asymmetric autocatalysis is a reaction in which the chiral product acts as an asymmetric catalyst to give more of itself of the same absolute configuration. Asymmetric autocatalysis of 2-alkynylpyrimidyl alkanol in the enantioselective addition of diisopropylzinc exhibits enormous asymmetric amplification. This asymmetric autocatalysis with amplification of ee can discriminate the small enantiomeric imbalance induced by the proposed candidates for the origin of chirality, such as circularly polarized light, inorganic and organic chiral crystals, spontaneous absolute asymmetric synthesis, and isotope chirality. Copyright © 2014 The Chemical Society of Japan and Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Okazaki T.,Chiyoda Corporation | Okazaki T.,Nippon Steel & Sumitomo Metal Corporation | Yamaguchi M.,Tokyo University of Science
Energy Policy | Year: 2011

It is imperative to tackle the issue globally mobilizing all available policies and measures. One of the important ones among them is technology transfer and diffusion. By utilizing international co-operation, industry can promote such measures in two ways: through government policy and through industry's own voluntary initiative. Needless to say, various government policies and measures play essential role. By the same token, industry initiative can complement them. There is much literature documenting the former. On the contrary there are few on the latter. This paper sheds light on the latter. The purpose of this paper is to explore the effectiveness of global voluntary sectoral approach for technology diffusion and transfer based on steel sector experience.The goal is to contribute toward building a worldwide low-carbon society by manufacturing goods with less energy through international cooperation of each sector. The authors believe that the voluntary sectoral approach is an effective method with political and practical feasibilities, and hope to see the continued growth of more initiatives based on this approach. © 2010 Elsevier Ltd.

Kho Y.K.,University of New South Wales | Iwase A.,University of New South Wales | Teoh W.Y.,University of New South Wales | Madler L.,University of Bremen | And 2 more authors.
Journal of Physical Chemistry C | Year: 2010

Photocatalytic H2 evolution over aqueous TiO2 suspension, with methanol as holes scavenger, is systematically studied as a function of anatase and rutile phase compositions. The highly crystalline, flame-synthesized TiO2 nanoparticles (22-36 m2 g -1) were designed to contain 4-95 mol % anatase, with the remaining being rutile. Although the amount of photocurrent generated under applied potential bias increases with increasing anatase content, a different trend was observed during photocatalytic H2 evolution in suspension form; that is, without potential bias. Here, synergistic effects in terms of H2 evolution were observed for a wide range of anatase contents, from 13 to 79 mol %. At the optimal 39 mol % anatase, the photocatalytic activity was enhanced by more than a factor of 2 with respect to the anatase- and rutile-rich phases. The synergistic effect in these mixed anatase-rutile phases was thought to originate from the efficient charge separation across phase junctions. No synergistic effect was observed for the physically mixed anatase and rutile particles due to insufficient physical contact. Here, we also identify the formation of highly reducing hydroxymethyl radicals during the simultaneous oxidation of methanol, which efficiently inject additional electrons into the TiO2 conduction band, that is, current-doubling, for heterogeneous (instead of homogeneous) H2 evolution. © 2010 American Chemical Society.

Matsueda H.,Sendai National College of Technology | Ishihara M.,Tohoku University | Hashizume Y.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

A tensor-network variational formalism of thermofield dynamics is introduced. The formalism relates the original Hilbert space with its tilde space by a product of two copies of a tensor network. Then, their interface becomes an event horizon, and the logarithm of the tensor rank corresponds to the black hole entropy. Eventually, a multiscale entanglement renormalization ansatz reproduces an anti-de Sitter black hole at finite temperature. Our finding shows rich functionalities of multiscale entanglement renormalization ansatz as efficient graphical representation of AdS/CFT correspondence. © 2013 American Physical Society.

Hirai M.,Tokyo University of Science | Kumano S.,Graduate University for Advanced Studies
Computer Physics Communications | Year: 2012

Semi-inclusive hadron-production processes are becoming important in high-energy hadron reactions. They are used for investigating properties of quark-hadron matters in heavy-ion collisions, for finding the origin of nucleon spin in polarized lepton-nucleon and nucleon-nucleon reactions, and possibly for finding exotic hadrons. In describing the hadron-production cross sections in high-energy reactions, fragmentation functions are essential quantities. A fragmentation function indicates the probability of producing a hadron from a parton in the leading order of the running coupling constant αs. Its Q2 dependence is described by the standard DGLAP (Dokshitzer-Gribov-Lipatov-Altarelli-Parisi) evolution equations, which are often used in theoretical and experimental analyses of the fragmentation functions and in calculating semi-inclusive cross sections. The DGLAP equations are complicated integro-differential equations, which cannot be solved in an analytical method. In this work, a simple method is employed for solving the evolution equations by using Gauss-Legendre quadrature for evaluating integrals, and a useful code is provided for calculating the Q2 evolution of the fragmentation functions in the leading order (LO) and next-to-leading order (NLO) of αs. The renormalization scheme is MS̄ in the NLO evolution. Our evolution code is explained for using it in one's studies on the fragmentation functions. © 2012 Elsevier B.V. All rights reserved.

Guo W.,Tokyo University of Science | Fukatsu T.,Japan National Agriculture and Food Research Organization | Ninomiya S.,Tokyo University of Science
Plant Methods | Year: 2015

Background: Flowering (spikelet anthesis) is one of the most important phenotypic characteristics of paddy rice, and researchers expend efforts to observe flowering timing. Observing flowering is very time-consuming and labor-intensive, because it is still visually performed by humans. An image-based method that automatically detects the flowering of paddy rice is highly desirable. However, varying illumination, diversity of appearance of the flowering parts of the panicles, shape deformation, partial occlusion, and complex background make the development of such a method challenging. Results: We developed a method for detecting flowering panicles of rice in RGB images using scale-invariant feature transform descriptors, bag of visual words, and a machine learning method, support vector machine. Applying the method to time-series images, we estimated the number of flowering panicles and the diurnal peak of flowering on each day. The method accurately detected the flowering parts of panicles during the flowering period and quantified the daily and diurnal flowering pattern. Conclusions: A powerful method for automatically detecting flowering panicles of paddy rice in time-series RGB images taken under natural field conditions is described. The method can automatically count flowering panicles. In application to time-series images, the proposed method can well quantify the daily amount and the diurnal changes of flowering during the flowering period and identify daily peaks of flowering. © Guo et al.; licensee BioMed Central.

Nishioka K.,Nippon Steel & Sumitomo Metal Corporation | Nishioka K.,Tokyo University of Science | Ichikawa K.,Tube and Shape Research Laboratory
Science and Technology of Advanced Materials | Year: 2012

The water-cooled thermomechanical control process (TMCP) is a technology for improving the strength and toughness of water-cooled steel plates, while allowing control of the microstructure, phase transformation and rolling. This review describes metallurgical aspects of the microalloying of steel, such as niobium addition, and discusses advantages of TMCP, for example, in terms of weldability, which is reduced upon alloying. Other covered topics include the development of equipment, distortions in steel plates, peripheral technologies such as steel making and casting, and theoretical modeling, as well as the history of property control in steel plate production and some early TMCP technologies. We provide some of the latest examples of applications of TMCP steel in various industries such as shipbuilding, offshore structures, building construction, bridges, pipelines, penstocks and cryogenic tanks. This review also introduces high heat-affected-zone toughness technologies, wherein the microstructure of steel is improved by the addition of fine particles of magnesium-containing sulfides and magnesium- or calcium-containing oxides. We demonstrate that thanks to ongoing developments TMCP has the potential to meet the ever-increasing demands of steel plates. © 2012 National Institute for Materials Science.

Tsukahara T.,KTH Royal Institute of Technology | Tsukahara T.,Tokyo University of Science | Tillmark N.,KTH Royal Institute of Technology | Alfredsson P.H.,KTH Royal Institute of Technology
Journal of Fluid Mechanics | Year: 2010

Flow states in plane Couette flow in a spanwise rotating frame of reference have been mapped experimentally in the parameter space spanned by the Reynolds number and rotation rate. Depending on the direction of rotation, the flow is either stabilized or destabilized. The experiments were made through flow visualization in a Couette flow apparatus mounted on a rotating table, where reflected flakes are mixed with the water to visualize the flow. Both short-and long-time exposures have been used: the short-time exposure gives an instantaneous picture of the turbulent flow field, whereas the long-time exposure averages the small, rapidly varying scales and gives a clearer representation of the large scales. A correlation technique involving the light intensity of the photographs made it possible to obtain, in an objective manner, both the spanwise and streamwise wavelengths of the flow structures. During these experiments 17 different flow regimes have been identified, both laminar and turbulent with and without roll cells, as well as states that can be described as transitional, i.e. states that contain both laminar and turbulent regions at the same time. Many of these flow states seem to be similar to those observed in Taylor-Couette flow. © 2010 Cambridge University Press.

Nishijo J.,Meisei University | Nishijo J.,Graduate University for Advanced Studies | Enomoto M.,Tokyo University of Science
Inorganic Chemistry | Year: 2013

The crystal structures and magnetic properties of a series of new weak ferromagnets containing a chromium-acetylide-tetrathiafulvalene (TTF) type complex, [CrCyclam(Cî - C-5-methyl-4′5′-ethylenedithio-TTF) 2]2+ ([1]2+), were investigated. The six new isostructural weak ferromagnets [1][BF4]2(PhF) 2(MeCN), [1][ClO4]2(PhF)2(MeCN), [1][ReO4]2(PhCl)2(MeCN), [1][ClO 4]2(PhBr)3, [1][ReO4] 2(PhBr)3, and [1][ClO4]2(PhI) 3 contain ferrimagnetic chain structures of [1]2+ ∞ with different interchain distances that are dependent on the sizes of the anions and solvent molecules. Magnetic measurements of the salts revealed that the weak ferromagnetic transition temperature gradually increases from 14.5 to 26.0 K as the interchain distance decreases from 3.997(2) to 3.803(2) Å, while the remanent magnetization at 2 K decreases from 0.0215 to 0.0079 μB. The observed magnetic properties and crystal structures suggest that the weak ferromagnetism originates from the single-ion anisotropy of [1]2+, where a stronger interchain antiferromagnetic interaction not only causes a higher transition temperature but also suppresses the noncollinear canted spin alignment. © 2013 American Chemical Society.

Fuseya Y.,University of Electro - Communications | Ogata M.,University of Tokyo | Fukuyama H.,Tokyo University of Science
Journal of the Physical Society of Japan | Year: 2014

Spin-Hall conductivity σ;sxy and orbital susceptibility X are investigated for the anisotropic Wolff Hamiltonian, which is an effective Hamiltonian common to Dirac electrons in solids. It is found that, both for σsxy and X, the effect of anisotropy appears only in the prefactors, which is given as the Gaussian curvature of the energy dispersion, and their functional forms are equivalent to those of the isotropic Wolff Hamiltonian. As a result, it is revealed that the relationship between the spin Hall conductivity and the orbital susceptibility in the insulating state, σsxy = (3mc2/he)X, which was firstly derived for the isotropic Wolff Hamiltonian, is also valid for the anisotropic Wolff Hamiltonian. Based on this theoretical finding, the magnitude of spin-Hall conductivity is estimated for bismuth and its alloys with antimony by that of orbital susceptibility, which has good correspondence between theory and experiments. The magnitude of spin-Hall conductivity turns out to be as large as eσsxy ∼ 104 Ω -1 cm-1, which is about 100 times larger than that of Pt. © 2014 The Physical Society of Japan.

Nesseris S.,Autonomous University of Madrid | Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

Nonlocal massive gravity can provide an interesting explanation for the late-time cosmic acceleration, with a dark energy equation of state wDE smaller than -1 in the past. We derive the equations of linear cosmological perturbations to confront such models with the observations of large-scale structures. The effective gravitational coupling to nonrelativistic matter associated with galaxy clusterings is close to Newton's gravitational constant G for a mass scale m slightly smaller than today's Hubble parameter H0. Taking into account the background expansion history as well as the evolution of matter perturbations δm, we test for these models with Type Ia Supernovae (SnIa) from Union 2.1, the cosmic microwave background (CMB) measurements from Planck, a collection of baryon acoustic oscillations (BAO), and the growth rate data of δm. Using a higher value of H0 derived from its direct measurement (H070 km s-1 Mpc-1) the data strongly support the nonlocal massive gravity model (-1.1wDE-1.04 in the past) over the ΛCDM model (wDE=-1), whereas for a lower prior (67 km s-1 Mpc-1H070 km s-1 Mpc-1) the two models are statistically comparable. © 2014 American Physical Society.

Sakata S.,University of Electro - Communications | Fujisawa M.,Tokyo University of Science
IEEE Transactions on Information Theory | Year: 2014

Multipoint codes are a broad class of algebraic geometry codes derived from algebraic functions, which have multiple poles and/or zeros on an algebraic curve. Thus, they are more general than one-point codes, which are an important class of algebraic geometry codes in the sense that they can be decoded efficiently using the Berlekamp-Massey-Sakata algorithm. We present a fast method for decoding multipoint codes from a plane curve, particularly a Hermitian curve. Our method with some adaptation can be applied to decode multipoint codes from a general algebraic curve embedded in the N-dimensional affine space Fq N over a finite field Fq, so that those algebraic geometry codes can be decoded efficiently if the dimension N of the affine space, including the defining curve is small. © 1963-2012 IEEE.

Tokyo University of Science and Kowa Co. | Date: 2011-08-08

The present invention is to provide means to treat breast cancer and/or mastitis by topically administering a non-steroidal antiinflammatory analgetic agent and/or an anticancer agent and allowing them efficiently to arrive into the mammary gland. The present invention provides an iontophoretic preparation for treating breast cancer and/or mastitis which contains a non-steroidal antiinflammatory analgetic agent and/or an anticancer agent as an active ingredient and has a donor to be applied on a nipple part for topical administration of the active ingredient from the nipple part to the mammary gland by application of electric potential.

Fuseya Y.,University of Electro - Communications | Ogata M.,University of Tokyo | Fukuyama H.,Tokyo University of Science
Journal of the Physical Society of Japan | Year: 2015

Bismuth crystal is known for its noteworthy properties resulting from particular electronic states, e.g., the Shubnikov- de Haas effect and the de Haas-van Alphen effect. Above all, the large diamagnetism of bismuth had been a longstanding puzzle since soon after the establishment of quantum mechanics, which was resolved eventually in 1970, on the basis of the effective Hamiltonian derived by Wolff, as being due to the interband effects of a magnetic field in the presence of a large spin-orbit interaction. This Hamiltonian is essentially the same as the Dirac Hamiltonian but with spatial anisotropy and an effective velocity much smaller than the light velocity. This paper reviews recent progress in the theoretical understanding of transport and optical properties, such as the weak-field Hall effect together with the spin Hall effect, and the magneto-optic effect, of a system described by the Wolff Hamiltonian and its isotropic version with a special focus on exploring the possible relationship with orbital magnetism. It is shown that there is a fundamental relationship between the spin Hall conductivity and orbital susceptibility in the insulating state, and the possibility of a fully spin-polarized electric current in magneto-optics. Experimental tests of these interesting features have been proposed. © 2015 The Physical Society of Japan.

Zhang M.,China Agricultural University | Zhang M.,The Jackson Laboratory | Su Y.-Q.,The Jackson Laboratory | Sugiura K.,The Jackson Laboratory | And 3 more authors.
Science | Year: 2010

Granulosa cells of mammalian Graafian follicles maintain oocytes in meiotic arrest, which prevents their precocious maturation. We show that mouse mural granulosa cells, which line the follicle wall, express natriuretic peptide precursor type C (Nppc) messenger RNA (mRNA), whereas cumulus cells surrounding oocytes express mRNA of the NPPC receptor NPR2, a guanylyl cyclase.NPPC increased cGMP levels in cumulus cells and oocytes and inhibited meiotic resumption in vitro. Meiotic arrest was not sustained in most Graafian follicles of Nppc or Npr2 mutant mice, and meiosis resumed precociously. Oocyte-derived paracrine factors promoted cumulus cell expression of Npr2 mRNA. Therefore, the granulosa cell ligand NPPC and its receptor NPR2 in cumulus cells prevent precocious meiotic maturation, which is critical for maturation and ovulation synchrony and for normal female fertility.

Nagai K.H.,Japan Advanced Institute of Science and Technology | Sumino Y.,Tokyo University of Science | Montagne R.,Federal Rural University of Pernambuco | Aranson I.S.,Argonne National Laboratory | And 3 more authors.
Physical Review Letters | Year: 2015

We show that memory, in the form of underdamped angular dynamics, is a crucial ingredient for the collective properties of self-propelled particles. Using Vicsek-style models with an Ornstein-Uhlenbeck process acting on angular velocity, we uncover a rich variety of collective phases not observed in usual overdamped systems, including vortex lattices and active foams. In a model with strictly nematic interactions the smectic arrangement of Vicsek waves giving rise to global polar order is observed. We also provide a calculation of the effective interaction between vortices in the case where a telegraphic noise process is at play, explaining thus the emergence and structure of the vortex lattices observed here and in motility assay experiments. © 2015 American Physical Society.

Horikoshi S.,Sophia University | Osawa A.,Sophia University | Osawa A.,Tokyo University of Science | Abe M.,Tokyo University of Science | Serpone N.,University of Pavia
Journal of Physical Chemistry C | Year: 2011

This article examines the generation of hot-spots and their impact in the heterogeneous Suzuki-Miyaura coupling reaction for the synthesis of 4-methylbiphenyl in toluene solvent in the presence of Pd/AC. Hot-spots easily formed on the surface of the activated carbon (AC) catalyst support under high electric field conditions; they were recorded in real time using a high-speed camera. Chemical yields of 4-methylbiphenyl under the microwaves magnetic field (H-field) were 2-fold greater than those under electric field (E-field) conditions at identical temperatures and reaction times (120 min). Microwave E-field irradiation with a high accuracy device enhanced generation of hot-spots. Excessive formation of hot-spots impacted negatively on this coupling reaction. © 2011 American Chemical Society.

Delsate T.,University of Lisbon | Delsate T.,University of Mons | Sawado N.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We consider the six-dimensional brane world model, where the brane is described by a localized solution to the baby-Skyrme model extending in the extra dimensions. The branes have a cosmological constant modeled by inflating four-dimensional slices and we further consider a bulk cosmological constant. We focus on the topological number three solutions and discuss the localization mechanism of the fermions on the above 3-branes. We discuss interpretation of the model in term of quark third-generation mass and in terms of the inflation history. We argue that the model can describe various epochs of the early Universe by suitably choosing the parameters. We further discuss the localization properties of gauge fields on the brane and argue that this is achieved only for specific values of the electromagnetic coupling, providing a quantization to the electric charge. © 2012 American Physical Society.

Shafieloo A.,Asia Pacific Center for Theoretical Physics | Shafieloo A.,Pohang University of Science and Technology | Shafieloo A.,University of Seoul | Sahni V.,Inter-University Center for Astronomy and Astrophysics | Starobinsky A.A.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

Baryon acoustic oscillations (BAO) provide an important standard ruler which can be used to probe the recent expansion history of our Universe. We show how a simple extension of the Om diagnostic, which we call Om3, can combine standard ruler information from BAO with standard candle information from type Ia supernovae (SNIa) to yield a powerful novel null diagnostic of the cosmological constant hypothesis. A unique feature of Om3 is that it requires minimal cosmological assumptions since its determination does not rely upon prior knowledge of either the current value of the matter density Ω 0m and the Hubble constant H 0 or the distance to the last scattering surface. Observational uncertainties in these quantities, therefore, do not affect the reconstruction of Om3. We reconstruct Om3 using the Union 2.1 SNIa data set and BAO data from SDSS, WiggleZ and 6dFGS. Our results are consistent with dark energy being the cosmological constant. We show how Om and Om3 can be used to obtain accurate model-independent constraints on the properties of dark energy from future data sets such as BigBOSS. © 2012 American Physical Society.

Dornbrack A.,German Aerospace Center | Pitts M.C.,NASA | Poole L.R.,Science Systems And Applications Inc. | Orsolini Y.J.,Norwegian Institute For Air Research | And 2 more authors.
Atmospheric Chemistry and Physics | Year: 2012

The relatively warm 2009-2010 Arctic winter was an exceptional one as the North Atlantic Oscillation index attained persistent extreme negative values. Here, selected aspects of the Arctic stratosphere during this winter inspired by the analysis of the international field experiment RECONCILE are presented. First of all, and as a kind of reference, the evolution of the polar vortex in its different phases is documented. Special emphasis is put on explaining the formation of the exceptionally cold vortex in mid winter after a sequence of stratospheric disturbances which were caused by upward propagating planetary waves. A major sudden stratospheric warming (SSW) occurring near the end of January 2010 concluded the anomalous cold vortex period. Wave ice polar stratospheric clouds were frequently observed by spaceborne remote-sensing instruments over the Arctic during the cold period in January 2010. Here, one such case observed over Greenland is analysed in more detail and an attempt is made to correlate flow information of an operational numerical weather prediction model to the magnitude of the mountain-wave induced temperature fluctuations. Finally, it is shown that the forecasts of the ECMWF ensemble prediction system for the onset of the major SSW were very skilful and the ensemble spread was very small. However, the ensemble spread increased dramatically after the major SSW, displaying the strong non-linearity and internal variability involved in the SSW event. © 2012 Author(s).

Tokunaga A.,Tokyo University of Science | Tsukimoto M.,Tokyo University of Science | Harada H.,Suzuka University of Medical Science | Moriyama Y.,Okayama University of Science | Kojima S.,Tokyo University of Science
Journal of Biological Chemistry | Year: 2010

Recent reports have shown that T cell receptor (TCR)-dependent ATP release from T cells is involved in production of interleukin-2 (IL-2) through activation of P2 receptors. Stimulation of TCR induces ATP release from T cells through gap junction hemichannels and maxianion channels, at least in part. However, the mechanisms of ATP release from activated T cells are not fully understood. Here, we studied the mechanisms of ATP release during TCR-dependent T cell activation by investigating the effects of various inhibitors on TCR-dependent ATP release from murine T cells. We found that not only anion channel and gap junction hemichannel inhibitors, but also exocytosis inhibitors suppressed the ATP release. These results suggest that ATP release from murine T cells is regulated by various mechanisms, including exocytosis. An inhibitor of exocytosis, bafilomycin A, significantly blocked TCR signaling, such as Ca 2+ elevation and IL-2 production. Furthermore, bafilomycin A, ectonucleotidase, and P2Y6 receptor antagonist significantly inhibited production of pro-inflammatory cytokines from external antigen-restimulated splenocytes, indicating that vesicular exocytosis-mediated purinergic signaling has a significant role in TCR-dependent cytokine production. We also detected vesicular ATP in murine T cells and human T lymphoma Jurkat cells, both of which also expressed mRNA of SLC17A9, a vesicular nucleotide transporter. Knock down of SLC17A9 in Jurkat cells markedly reduced ATP release and cytosolic Ca2+ elevation after TCR stimulation, suggesting involvement of SLC17A9-dependent vesicular exocytosis in ATP release and T cell activation. In conclusion, vesicular exocytosis of ATP appears to play a role in T cell activation and immune responses. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.

Motomura Y.,Tokyo University of Science | Motomura Y.,RIKEN | Morita H.,National Health Research Institute | Moro K.,RIKEN | And 10 more authors.
Immunity | Year: 2014

Allergic asthma is an inflammatory disease characterized by lung eosinophilia controlled by type 2 cytokines. Cysteine proteases are potent triggers ofallergic inflammation by causing barrier disruptionin lung epithelial cells inducing the elevation of interleukin-5 (IL-5) and IL-13 from natural helper (NH) cells, a member of ILC2s, which leads to lung eosinophilia. In this study, we found that basophils play a crucial role in NH cell-mediated eosinophilic inflammation induced by protease allergens. Conditional deletion of basophils caused a resolution of the papain-induced eosinophilia and mucus production. Resolution of eosinophilia was also observed in mice lacking IL-4 specifically in basophils, indicating that basophil-derived IL-4 enhanced expression of the chemokine CCL11, as well as IL-5, IL-9, and IL-13 in NH cells, thus attracting eosinophils. These results demonstrate that IL-4 from basophils has an important role in the NH-derived cytokine and chemokine expression, subsequently leading to protease allergen-induced airway inflammation. © 2014 Elsevier Inc.

Morita H.,Hoshi University | Takeya K.,Tokyo University of Science
Heterocycles | Year: 2010

Cyclic peptides comprise a class of naturally occurring molecules, which exhibit a range of biological activities, and have attracted great interest from a biogenetic point of view as well as providing challenging targets for total synthesis. This review covered the structure elucidation and biological activity of cyclic peptides recently isolated from higher plants such as Amaranthaceae, Annonaceae, Caryophyllaceae, Compositae, Linaceae, Rutaceae, and Rubiaceae. © 2010 The Japan Institute of Heterocyclic Chemistry Received.

Hill D.A.,University of Pennsylvania | Siracusa M.C.,University of Pennsylvania | Abt M.C.,University of Pennsylvania | Kim B.S.,University of Pennsylvania | And 9 more authors.
Nature Medicine | Year: 2012

Commensal bacteria that colonize mammalian barrier surfaces are reported to influence T helper type 2 (T H2) cytokine-dependent inflammation and susceptibility to allergic disease, although the mechanisms that underlie these observations are poorly understood. In this report, we find that deliberate alteration of commensal bacterial populations via oral antibiotic treatment resulted in elevated serum IgE concentrations, increased steady-state circulating basophil populations and exaggerated basophil-mediated T H2 cell responses and allergic inflammation. Elevated serum IgE levels correlated with increased circulating basophil populations in mice and subjects with hyperimmunoglobulinemia E syndrome. Furthermore, B cell-intrinsic expression of myeloid differentiation factor 88 (MyD88) was required to limit serum IgE concentrations and circulating basophil populations in mice. Commensal-derived signals were found to influence basophil development by limiting proliferation of bone marrow-resident precursor populations. Collectively, these results identify a previously unrecognized pathway through which commensal-derived signals influence basophil hematopoiesis and susceptibility to T H2 cytokine-dependent inflammation and allergic disease. © 2012 Nature America, Inc. All rights reserved.

Takai E.,Tokyo University of Science | Tsukimoto M.,Tokyo University of Science | Harada H.,Suzuka University of Medical Science | Sawada K.,Okayama University of Science | And 2 more authors.
Journal of Cell Science | Year: 2012

TGF-Β1 plays a key role in cancer progression through induction of various biological effects, including cell migration. Extracellular nucleotides, such as ATP, released from cells play a role in signaling through activation of P2 receptors. We show here that exocytosis of ATP followed by activation of P2 receptors play a key role in TGFΒ1-induced actin remodeling associated with cell migration. Treatment with TGF-Β1 facilitated migration of human lung cancer A549 cells, which was blocked by pretreatment with ectonucleotidase and P2 receptor antagonists. ATP and P2 agonists facilitated cell migration. TGFΒ1-induced actin remodeling, which contributes to cell migration, was also suppressed by pretreatment with ecto-nucleotidase and P2 receptor antagonists. Knockdown of P2X7 receptor suppressed TGFΒ1-induced migration and actin remodeling. These results indicate the involvement of TGFΒ1-induced ATP release in cell migration, at least in part, through activation of P2X7 receptors. TGFΒ1 caused release of ATP from A549 cells within 10 minutes. Both ATP-enriched vesicles and expression of a vesicular nucleotide transporter (VNUT) SLC17A9, which is responsible for exocytosis of ATP, were found in cytosol of A549 cells. TGFΒ1 failed to induce release of ATP from SLC17A9-knockdown cells. TGFΒ1-induced cell migration and actin remodeling were also decreased in SLC17A9-knockdown cells. These results suggest the importance of exocytosis of ATP in cell migration. We conclude that autocrine signaling through exocytosis of ATP and activation of P2 receptors is required for the amplification of TGFΒ1-induced migration of lung cancer cells. © 2012.

Kurita T.,Tokushima Bunri University | Makino Y.,Tokushima Bunri University | Makino Y.,Tokyo University of Science
Anticancer Research | Year: 2013

Curcumin, a natural polyphenolic compound derived from turmeric (Curcuma longa L), has proven to be a modulator of multiple intercellular signalling pathways linked to inflammation, to proliferation, growth, invasion, drug sensitivity, angiogenesis and metastasis of cancer cells. Although curcumin has shown significant efficacy in cell culture studies, it has shown limited efficacy in clinical studies when administered in conventional oral formulations. This discrepancy is largely attributed to its poor oral bioavailability, which may result from its poor solubility, its poor pharmacokinetic profile, or a combination of both. To circumvent these barriers, alternative drug delivery strategies and systems should be explored. In this article, after a brief review of the physicochemical properties and pharmacokinetic profiles of curcumin, recent advances in curcumin oral delivery systems are discussed.

Serpone N.,University of Pavia | Horikoshi S.,Tokyo University of Science | Emeline A.V.,Saint Petersburg State University
Journal of Photochemistry and Photobiology C: Photochemistry Reviews | Year: 2010

This review article focuses, albeit non-exhaustively, on the influence of microwave radiation on photoassisted processes often referred to as Advanced Oxidation Processes. In particular, we describe and illustrate the possible advantages of microwaves in TiO2-assisted photodegradations and photomineralizations of various organic pollutants such as herbicides and endocrine disruptors, among others. Described are also various reactor configurations involving UV/visible radiation and microwaves, with the former being supplied either by traditional Hg lamps or alternatively by electrodeless lamps activated by microwaves. To place the use of microwaves on processes occurring in aqueous TiO2 dispersions in perspective regarding environmental applications, we first introduce the various sources of pollutants and subsequently describe in brief the various advanced oxidation processes such as UV/peroxidation, UV/ozonation and the photo-Fenton process(es) in addition to direct photolysis either by sunlight or by artificial light sources. © 2010 Elsevier B.V.

Koyama K.,Obihiro University of Agriculture and Veterinary Medicine | Koyama K.,Ishikawa Prefectural University | Takemoto S.,Tokyo University of Science
Scientific Reports | Year: 2014

Midday depression of photosynthesis has important consequences for ecosystem carbon exchange. Recent studies of forest trees have demonstrated that latent reduction of photosynthetic capacity can begin in the early morning, preceding the midday depression. We investigated whether such early morning reduction also occurs in an herbaceous species, Oenothera biennis. Diurnal changes of the photosynthetic light response curve (measured using a light-emitting diode) and incident sunlight intensity were measured under field conditions. The following results were obtained: (1) the light-saturated photosynthetic rate decreased beginning at sunrise; (2) the incident sunlight intensity on the leaves increased from sunrise; and (3) combining (1) and (2), the net photosynthetic rate under natural sunlight intensity increased from sunrise, reached a maximum at mid-morning, and then showed midday depression. Our results demonstrate that the latent morning reduction of photosynthetic capacity begins at sunrise, preceding the apparent midday depression, in agreement with previous studies of forest trees.

Disclosed is an antibody which can recognize a first antibody. The antibody can specifically recognize either one of the first antibody in an unconjugated form and the first antibody in the form conjugated with an antigen. Specifically, the specifically recognizing antibody is an antibody which can specifically recognize and conjugate with the first antibody in the form conjugated with an antigen (i.e., a domino antibody) or an antibody which can specifically recognize and conjugate with the first antibody in an unconjugated form (i.e., an antibody unlocking antibody).

Disclosed is an antibody which can recognize a first antibody. The antibody can specifically recognize either one of the first antibody in an unconjugated form and the first antibody in the form conjugated with an antigen. Specifically, the specifically recognizing antibody is an antibody which can specifically recognize and conjugate with the first antibody in the form conjugated with an antigen (i.e., a domino antibody) or an antibody which can specifically recognize and conjugate with the first antibody in an unconjugated form (i.e., an antibody unlocking antibody).

Ideal Star Inc. and Tokyo University of Science | Date: 2010-02-17

Provided are a gas sensor, which is extremely compact to be arranged for separated gas piping in semiconductor device manufacturing equipment, a gas measuring system using such gas sensor, and a gas detection module for the gas measuring system. The gas sensor is provided with a gas detection device containing a dielectric semiconductor, the electric conductivity of the gas detection device varying in response to the degree of adsorption of gases to the gas detection device, a capacitive element connected in series to the gas detection device, and a pair of electrodes which are connected to electric terminals of an electric element comprising the gas detection device and the capacitive element, wherein the gas sensor is capable of detecting the degree of adsorption of gases to the gas detection device from an electrical response changing in response to a voltage which is applied to the pair of electrodes and which periodically varies and reverses in polarity.

Tokyo University of Science and Shimadzu Corporation | Date: 2013-12-06

Measuring light emitted from a laser light source and split into four light rays through optical fibers is emitted into a space from emission units, and bent upward at a mirror. The measuring light passes through a window in the center of the sample stage and strikes a lower surface of the biological sample placed on the sample stage. A portion of fluorescence emitted through excitation by the measuring light passes through the window, is bent in an opposite direction from the measuring light by the mirror, and guided to a fluorescence camera. An objective lens, and a spectroscopic unit for separating visible wavelength components are horizontally arranged between the camera and the mirror. Although the projection of the measuring light and the detection of the fluorescence are performed perpendicularly to the biological sample, the optical components and elements are horizontally arranged.

Konishi K.,Kogakuin University | Furukawa T.,Tokyo University of Science
IEEE Signal Processing Letters | Year: 2011

This letter proposes a reweighted least squares algorithm for quadrature amplitude modulation (QAM) detector in blind equalization. Because the QAM detection problem is a non-convex combinatorial optimization problem, it is relaxed into a problem of minimizing the sum of logarithmic functions in order to overcome the combinatorial complexity. To find a local optimal solution of the problem, an iterative reweighted least squares based algorithm is proposed. Simulation results show that the proposed algorithm improves the accuracy of QAM detection in blind equalization. © 2011 IEEE.

Konishi K.,Kogakuin University | Furukawa T.,Tokyo University of Science
IEEE Signal Processing Letters | Year: 2011

This letter proposes an algorithm for the blind fractionally spaced equalization (FSE). We show that the rank minimization approach leads to the reduction of degrees of freedom in the blind FSE problem and improves the quality of equalization. By introducing the nuclear norm heuristic, the design problem of blind channel equalization is formulated as the nuclear norm minimization problem. We also show that the effect of noise is reduced by minimizing the nuclear norm. Numerical examples demonstrate the effectiveness of the proposed algorithm. © 2010 IEEE.

JX Nippon Mining & Metals Corporation and Tokyo University of Science | Date: 2015-02-25

Provided is a novel lithium complex oxide containing molybdenum. A complex oxide represented by the following compositional formula: Li_(x)M_(y)Mo_(z)O wherein M is one or two or more selected from the group consisting of Mn, Ru, Sn, Mg, Al, Ti, V, Cr, Fe, Co, Ni, Cu, and Zn; x is in the range of 0.60 to 0.75; y is in the range of 0.15 to 0.25; and z is in the range of 0.075 to 0.20.

Shimadzu Corporation and Tokyo University of Science | Date: 2014-06-11

Measuring light emitted from a laser light source 1 and split into four light rays through optical fibers is emitted into a space from emission units 3, and bent upward at a mirror 4. The measuring light passes through a window in the center of the sample stage 5 and strikes a lower surface of the biological sample 7 placed on the sample stage 5. A portion of fluorescence emitted through excitation by the measuring light passes through the window, is bent in an opposite direction from the measuring light by the mirror 4, and guided to a fluorescence camera 12. An objective lens 10, and a spectroscopic unit 11 for separating visible wavelength components are horizontally arranged between the camera 12 and the mirror 4. Although the projection of the measuring light and the detection of the fluorescence are performed perpendicularly to the biological sample 7, the optical components and elements are horizontally arranged, whereby the height and weight of the apparatus are reduced.

JX Nippon Mining & Metals Corporation and Tokyo University of Science | Date: 2016-10-26

Provided is a novel lithium complex oxide containing molybdenum. A complex oxide represented by the following compositional formula: Li_(x)M_(y)Mo_(z)O wherein M is one or two or more selected from the group consisting of Mn, Ru, Sn, Mg, Al, Ti, V, Cr, Fe, Co, Ni, Cu, and Zn; x is in the range of 0.60 to 0.75; y is in the range of 0.15 to 0.25; and z is in the range of 0.075 to 0.20.

Yu X.,CAS Shanghai Institutes for Biological Sciences | Yu X.,Shandong University | Li G.,Shandong University | Chen L.,CAS Shanghai Institutes for Biological Sciences | Chen L.,Tokyo University of Science
Bioinformatics | Year: 2014

Motivation: In this article, we develop a novel edge-based network i.e. edge-network, to detect early signals of diseases by identifying the corresponding edge-biomarkers with their dynamical network biomarker score from dynamical network biomarkers. Specifically, we derive an edge-network based on the second-order statistics representation of gene expression profiles, which is able to accurately represent the stochastic dynamics of the original biological system (with Gaussian distribution assumption) by combining with the traditional node-network, which is based only on the first-order statistics representation of the noisy data. In other words, we show that the stochastic network of a biological system can be described by the integration of its node-network and its edge-network in an accurate manner.Results: By applying edge-network analysis to gene expressions of healthy adults within live influenza experiment sampling at time points before the appearance of infection symptoms, we identified the edge-biomarkers (80 edges with 22 densely connected genes) discovered in edge-networks corresponding to symptomatic adults, which were used to predict the subsequent outcomes of influenza infection. In particular, we not only correctly predict the final infection outcome of each individual at an early time point before his/her clinic symptom but also reveal the key molecules during the disease progression. The prediction accuracy achieves ∼90% under the leave-one-out cross-validation. Furthermore, we demonstrate the superiority of our method on disease classification and predication by comparing with the conventional node-biomarkers. Our edge-network analysis not only opens a new way to understand pathogenesis at a network level due to the new representation for a stochastic network, but also provides a powerful tool to make the early diagnosis of diseases. © 2013 The Author 2013. Published by Oxford University Press. All rights reserved.

Miyashita N.,Tokyo University of Science | Miyashita N.,Tokyo University of Technology | Ahsan N.,Tokyo University of Science | Okada Y.,Tokyo University of Science
Progress in Photovoltaics: Research and Applications | Year: 2016

An improved photocurrent production is demonstrated in dilute nitride GaInNAsSb solar cells grown by molecular beam epitaxy. The photovoltaic properties were investigated by increasing the thickness of GaInNAsSb layers from 1.0 to 3.0 μm. The amount of photon absorption increased with increasing thickness. Yet an incomplete photocarrier collection was observed in the 2.0- and 3.0-μm-thick GaInNAsSb devices. This feature is due to a partial lack of electric field in the GaInNAsSb region. In order for complete carrier collection aided by the electric field, the background-doping level should be as low as ~1014 cm-3 in a thick undoped-GaInNAsSb absorption layer. Here, the effectiveness of annealing on improving the field-assisted carrier collection is shown. This is ascribed to a decrease of the background doping in the GaInNAsSb layer. In a properly designed device for a 1.0-eV GaInNAsSb cell, it is demonstrated that the external quantum efficiency can reach as high as 90% at wavelengths longer than the GaAs bandgap. Copyright © 2015 John Wiley & Sons, Ltd.

Mitsuishi Y.,Tohoku University | Taguchi K.,Tohoku University | Kawatani Y.,Tohoku University | Shibata T.,National Cancer Center Research Institute | And 4 more authors.
Cancer Cell | Year: 2012

Cancer cells consume large quantities of nutrients and maintain high levels of anabolism. Recent studies revealed that various oncogenic pathways are involved in modulation of metabolism. Nrf2, a key regulator for the maintenance of redox homeostasis, has been shown to contribute to malignant phenotypes of cancers including aggressive proliferation. However, the mechanisms with which Nrf2 accelerates proliferation are not fully understood. Here, we show that Nrf2 redirects glucose and glutamine into anabolic pathways, especially under the sustained activation of PI3K-Akt signaling. The active PI3K-Akt pathway augments the nuclear accumulation of Nrf2 and enables Nrf2 to promote metabolic activities that support cell proliferation in addition to enhancing cytoprotection. The functional expansion of Nrf2 reinforces the metabolic reprogramming triggered by proliferative signals. © 2012 Elsevier Inc..

Shibayama S.,University of Turin | Shibayama S.,Georgia Institute of Technology | Shibayama S.,Tokyo University of Science
Scientometrics | Year: 2011

Drawing on a database of the competitive research funds in the Japanese academia, this study examines the distribution of research grants at the university and individual levels. The data indicates high inequality at the university level and slightly lower inequality at the individual level. Over the last three decades, the total grant budget has greatly increased and an increasing number of researchers have received the funds. Simultaneously, large-size grants have become more common and multiple awarding (i.e., one researcher receives more than one grant simultaneously) has become more frequent. These changes taken together, the level of inequality has not been changed substantially. The extent of inequality largely differs between scientific fields; especially high in basic natural sciences and relatively low in social sciences. A close examination of inequality over researchers' career indicates different patterns of transition between fields and cohorts. Finally, both at the university and individual levels, the funding distribution is found more unequal than the distribution of publications as an output indicator. © 2011 Akadémiai Kiadó, Budapest, Hungary.

Li X.,Tokyo University of Science | Takahashi T.,Tokyo University of Science | Suzuki N.,Tokyo University of Science | Kaiser H.M.,Cornell University
Agricultural Systems | Year: 2011

This study analyzes the impacts of climate change on maize yields using an econometric model that incorporates climate, economic, and technology variables. The major finding is climate change will not universally cause negative impacts of maize yields in the United States and China. The results of a simulation of climate change on maize yields over the period 2008-2030 show that a combination of changes in temperature and precipitation can either bring positive or negative effects on maize yields. Furthermore, variation in regional climatic and economic conditions makes the impacts of climatic change on maize yields substantially different in different regions. In this research, the impacts of climate change on maize yields are not simply examined by climate factors. Economic and technology adaptation effects on maize yields are also incorporated. Thus, even with significant changes in climate conditions that alter the maize crop's growing environment and affect crop yields, a decrease in maize supply due to a decrease in maize yields would lead to an increase in the maize price, which in turn would induce farmers to add more investments in production inputs to raise yields. Thus, the decrease in actual yields may not be as dramatic as predicted in only climate factor considered cases. In this research, findings gained from the study can be used for early-staged policymaking decisions and advanced problem prevention programs. To ensure the continuous increase in maize yields in the future, further studies and research, as well as efficient environmental policies and actions are required. © 2010 Elsevier Ltd.

Tsuji I.,Tokyo University of Science | Shimodaira Y.,Tokyo University of Science | Kato H.,Tokyo University of Science | Kato H.,Tohoku University | And 2 more authors.
Chemistry of Materials | Year: 2010

Photophysical properties and photocatalytic activities for H2 evolution of the series of stannitetype complex sulfides A 2 I-Zn-AIV-S4 (AI = Cu and Ag; A IV = Sn and Ge) were studied. Diffuse reflection spectra and the plane-wave-based density functional theory (DFT) calculation suggested that the conduction bands were made up of Ge4s4p or Sn5s5p with S3p orbitals, while the valence bands consisted of Cu3d and Ag4d with S3p orbitals. The constituting elements of AI and AIV affected the photophysical and photocatalytic properties. Ru cocatalyst-loaded Cu2ZnGeS4, Ag2ZnGeS4, and Ag2ZnSnS4 showed high activities for photocatalyticH2 evolution from an aqueous Na2SK 2SO3 solution under visible-light irradiation. Combination of Cu and Ag made it possible that the CuAgZnSnS4 photocatalyst with a narrow band gap (1.4 eV) utilized a wide range of visible light for the H2 evolution. © 2010 American Chemical Society.

Sotani H.,Japan National Astronomical Observatory | Nakazato K.,Tokyo University of Science | Iida K.,Kochi University | Oyamatsu K.,Aichi Shukutoku University
Physical Review Letters | Year: 2012

We general-relativistically calculate the frequency of fundamental torsional oscillations of neutron star crusts, where we focus on the crystalline properties obtained from macroscopic nuclear models in a way that is dependent on the equation of state of nuclear matter. We find that the calculated frequency is sensitive to the density dependence of the symmetry energy, but almost independent of the incompressibility of symmetric nuclear matter. By identifying the lowest-frequency quasiperiodic oscillation in giant flares observed from soft gamma-ray repeaters as the fundamental torsional mode and allowing for the dependence of the calculated frequency on stellar models, we provide a lower limit of the density derivative of the symmetry energy as L 50MeV. © 2012 American Physical Society.

Imamura T.,Tokyo University of Science | Sasamoto T.,Chiba University
Physical Review Letters | Year: 2012

We obtain the first exact solution for the stationary one-dimensional Kardar-Parisi-Zhang equation. A formula for the distribution of the height is given in terms of a Fredholm determinant, which is valid for any finite time t. The expression is explicit and compact enough so that it can be evaluated numerically. Furthermore, by extending the same scheme, we find an exact formula for the stationary two-point correlation function. © 2012 American Physical Society.

Ferreira L.A.,University of Sao Paulo | Jaykka J.,University of Leeds | Sawado N.,Tokyo University of Science | Toda K.,Toyama Prefectural University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We construct analytical and numerical vortex solutions for an extended Skyrme-Faddeev model in a (3+1) dimensional Minkowski space-time. The extension is obtained by adding to the Lagrangian a quartic term, which is the square of the kinetic term, and a potential which breaks the SO(3) symmetry down to SO(2). The construction makes use of an ansatz, invariant under the joint action of the internal SO(2) and three commuting U(1) subgroups of the Poincaré group, and which reduces the equations of motion to an ordinary differential equation for a profile function depending on the distance to the x3 axis. The vortices have finite energy per unit length, and have waves propagating along them with the speed of light. The analytical vortices are obtained for a special choice of potentials, and the numerical ones are constructed using the successive over relaxation method for more general potentials. The spectrum of solutions is analyzed in detail, especially its dependence upon special combinations of coupling constants. © 2012 American Physical Society.

Sawai H.,Tokyo University of Science | Yamada S.,Waseda University | Kotake K.,Japan National Astronomical Observatory | Suzuki H.,Tokyo University of Science
Astrophysical Journal | Year: 2013

We studied the role of turbulent resistivity in the core-collapse of a strongly magnetized massive star, carrying out two-dimensional resistive-MHD simulations. Three cases with different initial strengths of magnetic field and rotation are investigated: (1) a strongly magnetized rotating core, (2) a moderately magnetized rotating core, and (3) a very strongly magnetized non-rotating core. In each case, one ideal-MHD model and two resistive-MHD models are computed. As a result of these computations, each model shows an eruption of matter assisted by magnetic acceleration (and also by centrifugal acceleration in the rotating cases). We found that resistivity attenuates the explosion in cases 1 and 2, while it enhances the explosion in case 3. We also found that in the rotating cases, the main mechanisms for the amplification of a magnetic field in the post-bounce phase are an outward advection of the magnetic field and a twisting of poloidal magnetic field lines by differential rotation, which are somewhat dampened down with the presence of resistivity. Although magnetorotational instability seems to occur in the rotating models, it plays only a minor role in magnetic field amplification. Another impact of resistivity is that on the aspect ratio. In the rotating cases, a large aspect ratio of the ejected matter, >2.5, attained in an ideal-MHD model is reduced to some extent in a resistive model. These results indicate that resistivity possibly plays an important role in the dynamics of strongly magnetized supernovae. © 2013. The American Astronomical Society. All rights reserved.

Ono A.,Kanagawa University | Torigoe H.,Tokyo University of Science | Tanaka Y.,Tohoku University | Okamoto I.,Kanagawa University
Chemical Society Reviews | Year: 2011

Pyrimidine base pairs in DNA duplexes selectively capture metal ions to form metal ion-mediated base pairs, which can be evaluated by thermal denaturation, isothermal titration calorimetry, and nuclear magnetic resonance spectroscopy. In this critical review, we discuss the metal ion binding of pyrimidine bases (thymine, cytosine, 4-thiothymine, 2-thiothymine, 5-fluorouracil) in DNA duplexes. Thymine-thymine (T-T) and cytosine-cytosine (C-C) base pairs selectively capture Hg(ii) and Ag(i) ions, respectively, and the metallo-base pairs, T-Hg(ii)-T and C-Ag(i)-C, are formed in DNA duplexes. The metal ion binding properties of the pyrimidine-pyrimidine pairs can be changed by small chemical modifications. The binding selectivity of a metal ion to a 5-fluorouracil-5-fluorouracil pair in a DNA duplex can be switched by changing the pH of the solution. Two silver ions bind to each thiopyrimidine-thiopyrimidine pair in the duplexes, and the duplexes are largely stabilized. Oligonucleotides containing these bases are commercially available and can readily be applied in many scientific fields (86 references). © The Royal Society of Chemistry 2011.

Hayashi Y.,Tokyo University of Science | Hayashi Y.,Tohoku University | Umemiya S.,Tokyo University of Science | Umemiya S.,Tohoku University
Angewandte Chemie - International Edition | Year: 2013

Pot luck: Prostaglandins regulate a broad range of physiological processes and some of their derivatives are used as effective drugs, but previously their preparation has required many steps. The title compounds were efficiently synthesized in a small number of synthetic steps by using a recently developed organocatalyst and practical, one-pot operations involving several successive reactions. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dai J.G.,Cornell University | Miyazawa M.,Tokyo University of Science
Queueing Systems | Year: 2013

We present three sets of results for the stationary distribution of a two-dimensional semimartingale-reflecting Brownian motion (SRBM) that lives in the non-negative quadrant. The SRBM data can equivalently be specified by three geometric objects, an ellipse and two lines, in the two-dimensional Euclidean space. First, we revisit the variational problem (VP) associated with the SRBM. Building on Avram et al. (Queueing Syst. 37: 259-289, 2001), we show that the value of the VP at a point in the quadrant is equal to the optimal value of a linear function over a convex domain. Depending on the location of the point, the convex domain is either D(1) or D(2) or D(1) ∩ D(2) where each D(i), i=1, 2, can easily be described by the three geometric objects. Our results provide a geometric interpretation for the value function of the VP and allow one to see geometrically when one edge of the quadrant has influence on the optimal path traveling from the origin to a destination point. Second, we provide a geometric condition that characterizes the existence of a product form stationary distribution. Third, we establish exact tail asymptotics of two boundary measures that are associated with the stationary distribution; a key step in our proof is to sharpen two asymptotic inversion lemmas in Dai and Miyazawa (Stoch. Syst. 1:146-208, 2011) which allow one to infer the exact tail asymptotic of a boundary measure from the singularity of its moment-generating function. © 2013 Springer Science+Business Media New York.

Liu B.,Wuhan University of Technology | Zhao X.,Wuhan University of Technology | Terashima C.,Tokyo University of Science | Fujishima A.,Tokyo University of Science | Nakata K.,Tokyo University of Science
Physical Chemistry Chemical Physics | Year: 2014

Since the report of the Honda-Fujishima effect, heterogeneous photocatalysis has attracted much attention around the world because of its potential energy and environmental applications. Although great progresses have been made in recent years, most were focused on preparing highly-active photocatalysts and investigating visible light utilization. In fact, we are still unclear on the thermodynamic and kinetic nature of photocatalysis to date, which sometimes leads to misunderstandings for experimental results. It is timely to give a review and discussion on the thermodynamics and kinetics of photocatalysis, so as to direct future researches. However, there is an absence of a detailed review on this topic until now. In this article, we tried to review and discuss the thermodynamics and kinetics of photocatalysis. We explained the thermodynamic driving force of photocatalysis, and distinguished the functions of light and heat in photocatalysis. The Langmuir-Hinshelwood kinetic model, the OH oxidation mechanism, and the direct-indirect (D-I) kinetic model were reviewed and compared. Some applications of the D-I model to study photocatalytic kinetics were also discussed. The electron transport mode and its importance in photocatalysis were investigated. Finally, the intrinsic relation between the kinetics and the thermodynamics of photocatalytic reactions was discussed. This journal is © the Partner Organisations 2014.

Naito K.,Japan National Institute of Materials Science | Yang J.-M.,University of California at Los Angeles | Xu Y.,Japan National Institute of Materials Science | Kagawa Y.,Tokyo University of Science
Carbon | Year: 2010

The thermal conductivities of ultrahigh tensile strength polyacrylonitrile (PAN)-based (T1000GB) and ultrahigh modulus pitch-based (K13D) carbon fibers with carbon nanotubes (CNTs) grown on them using chemical vapor deposition were measured using a thermal diffusivity meter. The thermal conductivities of the resulting hybrid materials were calculated to be 18.6 ± 1.7 and 965.6 ± 30.0 W/m K for T1000GB and K13D, respectively, while the respective original conductivities were 12.6 ± 1.0 and 745.5 ± 16.0 W/m K. The results clearly show that the CNTs grafting improves the thermal conductivities of both types of fiber. © 2010 Elsevier Ltd. All rights reserved.

Hirakawa A.,Pharmaceuticals and Medical Devices Agency | Hirakawa A.,Tokyo University of Science
Statistics in Medicine | Year: 2012

In this study, we developed a novel adaptive dose-finding approach for inclusion of correlated bivariate binary and continuous outcomes in designing phase I oncology trials. For this approach, binary toxicity and continuous efficacy outcomes are modeled jointly with a factorization model. The basic strategy of the proposed approach is based primarily on the Bayesian method. We based the dose escalation/de-escalation decision rules on the posterior distributions of both toxicity and efficacy outcomes. We compared the operating characteristics of the proposed and existing methods through simulation studies under various scenarios. We found that the recommendation rate of the true recommended dose (RD) in the proposed method was more favorable than that in the existing method when the true RD was relatively at the tail end among the tested doses. It was similar to that of the existing method when the true RD was relatively at the top end. © 2011 John Wiley & Sons, Ltd.

Iwase A.,Tokyo University of Science | Kato H.,Tokyo University of Science | Kato H.,Tohoku University | Kudo A.,Tokyo University of Science
Applied Catalysis B: Environmental | Year: 2013

Photocatalytic water splitting over La-doped NaTaO3 (NaTaO3:La) was improved by loading with Au cocatalyst which works as H2 evolution sites. NaTaO3:La loaded with Au by an impregnation method showed higher and more steady activity for water splitting than that by a photodeposition method. This difference in the activity for water splitting was related to the O2 photoreduction on the loaded Au cocatalyst, which is one of the backward reactions of water splitting. The impregnated spherical Au cocatalyst suppressed the O2 photoreduction by photogenerated electrons more efficiently than the photodeposited hemispherical Au cocatalyst, because the perimeter of Au/NaTaO3:La interface which produces activated O2 molecules was smaller in the impregnated Au than the photodeposited Au. © 2013 Elsevier B.V.

Kato H.,Tokyo University of Science | Kato H.,Tohoku University | Sasaki Y.,Tokyo University of Science | Shirakura N.,Tokyo University of Science | Kudo A.,Tokyo University of Science
Journal of Materials Chemistry A | Year: 2013

Two-step excitation photocatalytic systems called Z-scheme systems are attractive to achieve overall water splitting under visible light irradiation. The low activity of SrTiO3:Rh as a H2-evolving photocatalyst suppresses the overall efficiency of the Z-scheme system composed of SrTiO3:Rh modified with a Pt or Ru cocatalyst, BiVO4, and an Fe3+/Fe2+ electron mediator. In this study, improvement of efficiency for water splitting over the Z-scheme system has been achieved through the preparation of highly efficient SrTiO3:Rh photocatalysts by hydrothermal and polymerizable complex methods. It has also been revealed that excess amounts of Sr are necessary to obtain highly active SrTiO3:Rh photocatalysts. Apparent quantum yields of the Z-scheme systems were improved from 0.4% to 3.9-4.2% at 420 nm when SrTiO3:Rh prepared by HT and PC methods was used as a H2-evolving photocatalyst instead of that prepared by a solid state reaction. The efficiency of the improved Z-scheme system for solar energy conversion was determined to be 0.1%. © 2013 The Royal Society of Chemistry.

Horiguchi M.,Tokyo University of Science | Kojima H.,Tokyo University of Science | Sakai H.,Tokyo University of Science | Kubo H.,Tohoku University | Yamashita C.,Tokyo University of Science
Journal of Controlled Release | Year: 2014

Chronic obstructive pulmonary disease (COPD) is an intractable pulmonary disease, causes widespread and irreversible alveoli collapse. In search of a treatment target molecule, which is able to regenerate collapsed alveoli, we sought to identify a factor that induces differentiation in human alveolar epithelial stem cells using all-trans retinoic acid (ATRA), whose alveolar repair capacity has been reported in animal experiments. When human alveolar epithelial stem cells were exposed to ATRA at a concentration of 10 μM for over seven days, approximately 20% of the cells differentiated into each of the type-I and type-II alveolar epithelial cells that constitute the alveoli. In a microarray analysis, integrin-α1 and integrin-β3 showed the largest variation in the ATRA-treated group compared with the controls. Furthermore, the effect of the induction of differentiation in human alveolar epithelial stem cells using ATRA was suppressed by approximately one-fourth by siRNA treatments with integrin α1 and integrin β3. These results suggested that integrin α1 and β3 are factors responsible for the induction of differentiation in human alveolar epithelial stem cells. We accordingly investigated whether integrin nanoparticles also had a regenerative effect in vivo. Elastase-induced COPD model mouse was produced, and the alveolar repair effect of pulmonary administration using nanoparticles of integrin protein was evaluated by X-ray CT scanning. Improvement in the CT value in comparison with an untreated group indicated that there was an alveolar repair effect. In this study, it was shown that the differentiation-inducing effect on human alveolar epithelial stem cells by ATRA was induced by increased expression of integrin, and that the induced integrin enhanced phosphorylation signaling of AKT, resulting in inducing differentiations. Furthermore, the study demonstrated that lung administration of nanoparticles with increased solubility and stability of integrin repaired the alveolus of an Elastase-induced COPD model mouse. Those results show that those integrin nanoparticles are effective as novel COPD treatment target compounds. © 2014 Elsevier Ltd. All rights reserved.

Sotani H.,Japan National Astronomical Observatory | Nakazato K.,Tokyo University of Science | Iida K.,Kochi University | Oyamatsu K.,Aichi Shukutoku University
Monthly Notices of the Royal Astronomical Society: Letters | Year: 2013

We consider how superfluidity of dripped neutrons in the crust of a neutron star affects the frequencies of the crust's fundamental torsional oscillations.Anon-negligible superfluid part of dripped neutrons, which do not comove with nuclei, acts to reduce the enthalpy density and thus enhance the oscillation frequencies. By assuming that the quasi-periodic oscillations observed in giant flares of soft gammarepeaters arise from the fundamental torsional oscillations and that themass and radius of the neutron star are in the range 1.4≤M/M⊙ ≤1.8 and 10≤R≤14 km, we constrain the density derivative of the symmetry energy as 100 ≲ L ≲ 130 MeV, which is far more severe than the previous one, L ≳ 50 MeV, derived by ignoring the superfluidity. © 2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Sasaki Y.,Tokyo University of Science | Kato H.,Tokyo University of Science | Kato H.,Tohoku University | Kudo A.,Tokyo University of Science
Journal of the American Chemical Society | Year: 2013

[Co(bpy)3]3+/2+ and [Co(phen)3] 3+/2+ redox couples were revealed to play as electron mediators for Z-scheme photocatalyst systems composed of Ru/SrTiO3:Rh and BiVO 4 powders for overall water splitting under visible light irradiation. These electron mediators were effective for only the combination of SrTiO3:Rh with BiVO4. They did not work when nondoped SrTiO3 and TiO2 of H2-evolving photocatalysts and WO3 of O2-evolving photocatalysts were employed. These results indicated that the affinity between photocatalysts and the Co-complex electron mediators was important. The photocatalytic activity depended on pH. Neutral pH conditions gave the highest activity for overall water splitting. Overall water splitting by the present system steadily proceeded for a long time. The Z-scheme photocatalyst system was also confirmed to split water under sunlight irradiation at the rates depending on weather. Moreover, overall water splitting by the Z-scheme photocatalyst system with the Co-complex electron mediator using a reaction cell in which the Ru/SrTiO3:Rh suspension was divided from BiVO4 suspension by a membrane filter resulted in H2 evolution separated from that of O2. © 2013 American Chemical Society.

Hayashi Y.,Tohoku University | Kojima M.,Tokyo University of Science
ChemCatChem | Year: 2013

All selection should be this- eeasy: The direct asymmetric aldol reaction of commercial aqueous glyoxal is catalyzed by trifluoromethyl-substituted diarylprolinol 1 to afford a β-formyl-β-hydroxy-α-substituted aldehyde in good yield with excellent anti selectivity and excellent enantioselectivity. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Liu R.,South China University of Technology | Wang X.,Fudan University | Aihara K.,Tokyo University of Science | Chen L.,Tokyo University of Science | Chen L.,CAS Shanghai Institutes for Biological Sciences
Medicinal Research Reviews | Year: 2014

Many studies have been carried out for early diagnosis of complex diseases by finding accurate and robust biomarkers specific to respective diseases. In particular, recent rapid advance of high-throughput technologies provides unprecedented rich information to characterize various disease genotypes and phenotypes in a global and also dynamical manner, which significantly accelerates the study of biomarkers from both theoretical and clinical perspectives. Traditionally, molecular biomarkers that distinguish disease samples from normal samples are widely adopted in clinical practices due to their ease of data measurement. However, many of them suffer from low coverage and high false-positive rates or high false-negative rates, which seriously limit their further clinical applications. To overcome those difficulties, network biomarkers (or module biomarkers) attract much attention and also achieve better performance because a network (or subnetwork) is considered to be a more robust form to characterize diseases than individual molecules. But, both molecular biomarkers and network biomarkers mainly distinguish disease samples from normal samples, and they generally cannot ensure to identify predisease samples due to their static nature, thereby lacking ability to early diagnosis. Based on nonlinear dynamical theory and complex network theory, a new concept of dynamical network biomarkers (DNBs, or a dynamical network of biomarkers) has been developed, which is different from traditional static approaches, and the DNB is able to distinguish a predisease state from normal and disease states by even a small number of samples, and therefore has great potential to achieve "real" early diagnosis of complex diseases. In this paper, we comprehensively review the recent advances and developments on molecular biomarkers, network biomarkers, and DNBs in particular, focusing on the biomarkers for early diagnosis of complex diseases considering a small number of samples and high-throughput data (or big data). Detailed comparisons of various types of biomarkers as well as their applications are also discussed. © 2013 Wiley Periodicals, Inc.

Wang J.,CAS Academy of Mathematics and Systems Science | Huang Q.,CAS Academy of Mathematics and Systems Science | Liu Z.-P.,CAS Shanghai Institutes for Biological Sciences | Wang Y.,CAS Academy of Mathematics and Systems Science | And 4 more authors.
Nucleic Acids Research | Year: 2011

Gene ontology analysis has become a popular and important tool in bioinformatics study, and current ontology analyses are mainly conducted in individual gene or a gene list. However, recent molecular network analysis reveals that the same list of genes with different interactions may perform different functions. Therefore, it is necessary to consider molecular interactions to correctly and specifically annotate biological networks. Here, we propose a novel Network Ontology Analysis (NOA) method to perform gene ontology enrichment analysis on biological networks. Specifically, NOA first defines link ontology that assigns functions to interactions based on the known annotations of joint genes via optimizing two novel indexes 'Coverage' and 'Diversity'. Then, NOA generates two alternative reference sets to statistically rank the enriched functional terms for a given biological network. We compare NOA with traditional enrichment analysis methods in several biological networks, and find that: (i) NOA can capture the change of functions not only in dynamic transcription regulatory networks but also in rewiring protein interaction networks while the traditional methods cannot and (ii) NOA can find more relevant and specific functions than traditional methods in different types of static networks. Furthermore, a freely accessible web server for NOA has been developed at © 2011 The Author(s).

Imamura T.,Tokyo University of Science | Sasamoto T.,Chiba University | Sasamoto T.,TU Munich
Journal of Statistical Physics | Year: 2013

We study exact stationary properties of the one-dimensional Kardar-Parisi-Zhang (KPZ) equation by using the replica approach. The stationary state for the KPZ equation is realized by setting the initial condition the two-sided Brownian motion (BM) with respect to the space variable. Developing techniques for dealing with this initial condition in the replica analysis, we elucidate some exact nature of the height fluctuation for the KPZ equation. In particular, we obtain an explicit representation of the probability distribution of the height in terms of the Fredholm determinants. Furthermore from this expression, we also get the exact expression of the space-time two-point correlation function. © 2013 Springer Science+Business Media New York.

Ikeda N.,Kyoto Sangyo University | Uchino K.,Tokyo University of Science
Communications in Mathematical Physics | Year: 2011

A BV algebra and a QP-structure of the degree 3 is formulated. A QP-structure of degree 3 gives rise to Lie algebroids up to homotopy and its algebraic and geometric structure is analyzed. A new algebroid is constructed, which derives a new topological field theory in 4 dimensions by the AKSZ construction. © 2011 Springer-Verlag.

Imamura T.,Tokyo University of Science | Sasamoto T.,Chiba University
Journal of Physics A: Mathematical and Theoretical | Year: 2011

We consider the one-dimensional KardarParisiZhang (KPZ) equation with the half Brownian motion initial condition, studied previously through the weakly asymmetric simple exclusion process. We employ the replica Bethe ansatz and show that the generating function of the exponential moments of the height is expressed as a Fredholm determinant. From this, the height distribution and its asymptotics are studied. Furthermore, using the replica method we also discuss the multi-point height distribution. We find that some good properties of the deformed Airy functions play an important role in the analysis. © 2011 IOP Publishing Ltd.

Wu Z.,University of Shanghai for Science and Technology | Wang Y.,CAS Academy of Mathematics and Systems Science | Chen L.,CAS Shanghai Institutes for Biological Sciences | Chen L.,Tokyo University of Science
Molecular BioSystems | Year: 2013

Network-based computational biology, with the emphasis on biomolecular interactions and omics-data integration, has had success in drug development and created new directions such as drug repositioning and drug combination. Drug repositioning, i.e., revealing a drug's new roles, is increasingly attracting much attention from the pharmaceutical community to tackle the problems of high failure rate and long-term development in drug discovery. While drug combination or drug cocktails, i.e., combining multiple drugs against diseases, mainly aims to alleviate the problems of the recurrent emergence of drug resistance and also reveal their synergistic effects. In this paper, we unify the two topics to reveal new roles of drug interactions from a network perspective by treating drug combination as another form of drug repositioning. In particular, first, we emphasize that rationally repositioning drugs in the large scale is driven by the accumulation of various high-throughput genome-wide data. These data can be utilized to capture the interplay among targets and biological molecules, uncover the resulting network structures, and further bridge molecular profiles and phenotypes. This motivates many network-based computational methods on these topics. Second, we organize these existing methods into two categories, i.e., single drug repositioning and drug combination, and further depict their main features by three data sources. Finally, we discuss the merits and shortcomings of these methods and pinpoint some future topics in this promising field. © 2013 The Royal Society of Chemistry.

An active ray-curable composition characterized by containing a photobase generator, a double bond-containing compound, and a -dicarbonyl compound.

Koito Manufacturing Co. and Tokyo University of Science | Date: 2010-09-07

In a semiconductor device, a YAG substrate is formed as a single-crystal substrate of any of surface orientations (100), (110), and (111). In the fabrication of the semiconductor device, a TMAl gas is first fed onto the YAG substrate so as to form a nucleation layer made of aluminum, which is a group-III element. Then, an NH_(3 )gas is fed onto the nucleation layer. This turns the surface of the nucleation layer into a group-V element and then forms a group-III-V compound layer of AlN. Then, a mixed gas of TMAl gas and NH_(3 )gas is fed onto the group-III-V compound layer so as to form another group-III-V compound layer. Finally, a group-III nitride semiconductor layer is crystal-grown on the group-III compound layer.

Canon Kabushiki Kaisha and Tokyo University of Science | Date: 2010-02-04

Provided are a ferroelectric material having good ferroelectricity and good insulation property, and a ferroelectric device using the ferroelectric material. In the present invention, the ferroelectric material includes a metal oxide having a perovskite-type crystal structure, in which: the metal oxide contains bismuth ferrite whose iron is substituted by manganese, and at least one of a copper oxide and a nickel oxide; the bismuth ferrite is substituted by manganese at a substitution ratio of 0.5 at. % or more to 20 at. % or less with respect to a total amount of iron and manganese; and at least one of the copper oxide and the nickel oxide is added in an amount of 0.5 mol % or more to 20 mol % or less with respect to the bismuth ferrite whose iron is substituted by manganese.

An active ray-curable composition characterized by containing a photobase generator, a double bond-containing compound, and a -dicarbonyl compound.

Tokyo University of Science and Koito Manufacturing Co. | Date: 2012-11-19

In a semiconductor device, a YAG substrate is formed as a single-crystal substrate of any of surface orientations (100), (110), and (111). In the fabrication of the semiconductor device, a TMAl gas is first fed onto the YAG substrate so as to form a nucleation layer made of aluminum, which is a group-III element. Then, an NH_(3 )gas is fed onto the nucleation layer. This turns the surface of the nucleation layer into a group-V element and then forms a group-III-V compound layer of AlN. Then, a mixed gas of TMAl gas and NH_(3 )gas is fed onto the group-III-V compound layer so as to form another group-III-V compound layer. Finally, a group-III nitride semiconductor layer is crystal-grown on the group-III compound layer.

An active ray curable composition, including: a photobase generator; a polymerizable compound; and an acid, wherein the photobase generator is a salt of a carboxylic acid and a basic compound, wherein a ratio by mole of a carboxyl group of the carboxylic acid : a basic functional group of the basic compound is 1 : 1, and wherein the acid is an acid that loses a function thereof as acid by light or heat.

Home > Press > Oxford Instruments announces winner of the 2015 Sir Martin Wood Prize for leading young Japanese researchers Abstract: Oxford Instruments is delighted to announce Dr Takuya Satoh, Associate Professor, Faculty of Science of Kyushu University as the winner of the 2015 Sir Martin Wood Prize. Dr Satoh was awarded the prize for his work involving the generation and control of magnetic excitations by polarised light in anti-ferromagnets and ferrimagnets. Dr Satoh was awarded with the medal, certificate and a total cash prize of ¥500,000 at the British Embassy in Tokyo by Mr. Tim Hitchens, the British Ambassador on Wednesday, 11th November 2015. He also delivered a lecture presenting his work at the 2015 Millennium Science Forum held at the Embassy, organised by Oxford Instruments and chaired by Professor Noboru Miura of Tokyo University. Among the guest speakers at the event were Professor Masaki Takata from Tohoku University and Professor Kevin O’Grady from the University of York. "It truly is an honour to be the recipient of this prestigious prize and I am grateful to Oxford Instruments and the Sir Martin Wood Prize Committee for recognising my work", commented the winner. The Millennium Science Forum was established in 1998 to promote scientific exchange between Britain and Japan and award the Sir Martin Wood Prize to a young researcher from a Japanese University or research institute who has performed outstanding research in the area of condensed matter science. The prize is named after Sir Martin Wood, Founder and Honorary President of Oxford Instruments plc. Recent winners of the Sir Martin Wood Prize for Japan include – Dr Masamitsu Hayashi of NIMS (2014) Dr Naoya Shibata, the University of Tokyo (2013) Dr Daichi Chiba, Kyoto University (2012) The Sir Martin Wood Prize selection committee consists of eight senior professors from Japanese Universities and is chaired by Professor Hidetoshi Fukuyama from Tokyo University of Science. The Sir Martin Wood Prize winner receives ¥500,000 in cash and the opportunity to give a series of lectures in British Universities, including the University of Oxford. Further details of the Sir Martin Wood Prize and nomination procedures can be obtained from the Secretariat at or email to . More information on all the Science Prizes sponsored by Oxford Instruments can be found at: About Oxford Instruments NanoScience Oxford Instruments NanoScience designs, supplies and supports market-leading research tools that enable quantum technologies, new materials and device development in the physical sciences. Our tools support research down to the atomic scale through creation of high performance, cryogen free low temperature and magnetic environments, based upon our core technologies in low and ultra low temperatures, high magnetic fields and system integration, with ever-increasing levels of experimental and measurement readiness. Oxford Instruments NanoScience is a part of the Oxford Instruments plc group. About Oxford Instruments plc Oxford Instruments designs, supplies and supports high-technology tools and systems with a focus on research and industrial applications. Innovation has been the driving force behind Oxford Instruments' growth and success for over 50 years, and its strategy is to effect the successful commercialisation of these ideas by bringing them to market in a timely and customer-focused fashion. The first technology business to be spun out from Oxford University, Oxford Instruments is now a global company and is listed on the London Stock Exchange (OXIG). Its objective is to be the leading provider of new generation tools and systems for the research and industrial sectors with a focus on nanotechnology. Its key market sectors include nano-fabrication and nano-materials. The company’s strategy is to expand the business into the life sciences arena, where nanotechnology and biotechnology intersect. This involves the combination of core technologies in areas such as low temperature, high magnetic field and ultra high vacuum environments; Nuclear Magnetic Resonance; X-ray, electron, laser and optical based metrology; atomic force microscopy; optical imaging; advanced growth, deposition and etching. Oxford Instruments aims to pursue responsible development and deeper understanding of our world through science and technology. Its products, expertise, and ideas address global issues such as energy, environment, security and health. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Ushijima K.,Kyushu Sangyo University | Cantwell W.J.,Khalifa University | Chen D.H.,Tokyo University of Science
International Journal of Mechanical Sciences | Year: 2013

The mechanical properties of micro-lattice structures subjected to a normal stress state are investigated using both a classical beam theory approach and the finite element technique. In particular, an approach for predicting the yield surface of lattice structures subjected to either a uniaxial or a biaxial stress state is proposed. In addition, the geometrical and material conditions for the occurrence of elastic buckling under a triaxial stress state are identified. The stiffness and plastic collapse strengths of the micro-lattice structures are compared with the corresponding properties of other lightweight structures. It is shown that micro-lattices offer significant potential for use in the design of lightweight cellular structures. © 2013 Elsevier Ltd.

Tanaka S.,Hiroshima University | Okada H.,Tokyo University of Science | Okazawa S.,Hiroshima University
Computational Mechanics | Year: 2012

This study develops a wavelet Galerkin method (WGM) that uses B-spline wavelet bases for application to solid mechanics problems. A fictitious domain is often adopted to treat general boundaries in WGMs. In the analysis, the body is extended to its exterior but very low stiffness is applied to the exterior region. The stiffness matrix in the WGM becomes singular without the use of a fictitious domain. The problem arises from the lack of linear independence of the basis functions. A technique to remove basis functions that can be represented by the superposition of the other basis functions is proposed. The basis functions are automatically eliminated in the pre conditioning step. An adaptive strategy is developed using the proposed technique. The solution is refined by superposing finer wavelet functions. Numerical examples of solid mechanics problems are presented to demonstrate the multiresolution properties of the WGM. © 2011 Springer-Verlag.

Abe M.O.,Tokyo University of Science | Sternad D.,Northeastern University
Frontiers in Human Neuroscience | Year: 2013

Observable structure of variability presents a window into the underlying processes of skill acquisition, especially when the task affords a manifold of solutions to the desired task result. This study examined skill acquisition by analyzing variability in both its distributional and temporal structure. Using a virtual throwing task, data distributions were analyzed by the TNCmethod (Tolerance, Noise, Covariation); the temporal structure was quantified by autocorrelation and detrended fluctuation analysis. We tested four hypotheses: 1) Tolerance and Covariation, not Noise, are major factors underlying long-term performance improvement. 2) Trial-to-trial dynamics in execution space exhibits preferred directions in execution space. 3) The directiondependent organization of variability becomes more pronounced with practice. 4) The anisotropy is in directions orthogonal and parallel to the solution manifold. Results from 13 subjects practicing for six days revealed that performance improvement correlated with increasing Tolerance and Covariation; Noise remained relatively constant. Temporal fluctuations and their directional modulation were identified by a novel rotation method that was a priori ignorant about orthogonality. Results showed a modulation of time-dependent characteristics that became enhanced with practice. However, this directionality was not coincident with orthogonal and parallel directions of the solution manifold. A state-space model with two sources of noise replicated not only this temporal structure but also its deviations from orthogonality. Simulations suggested that practice-induced changes were associated with an increase in the feedback gain and a subtle weighting of the two noise sources. The directionality in the structure of variability depended on the scaling of the coordinates, a result that highlights that analysis of variability sensitively depends on the chosen coordinates. © 2013 Abe and Sternad.

Shibayama N.,Tokyo University of Science | Shibayama N.,Toppan Printing Co. | Ozawa H.,Tokyo University of Science | Abe M.,Toppan Printing Co. | And 2 more authors.
Chemical Communications | Year: 2014

Co-sensitized dye-sensitized solar cells using black dye and a pyridine-anchor dye (NI5 or YNI-2) showing site-selective adsorption behaviour at the TiO2 surface have been prepared for the first time to reduce the competitive adsorption between the two dyes. © the Partner Organisations 2014.

Hisamatsu Y.,University of Duisburg - Essen | Hisamatsu Y.,Tokyo University of Science | Banerjee S.,University of Duisburg - Essen | Avinash M.B.,Jawaharlal Nehru Centre for Advanced Scientific Research | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

Four arms: A quadruple zwitterion based on a pentaerythritol core forms thermoreversible gels in DMSO driven by the formation of ion-paired dimers between the zwitterionic units. Furthermore, it exhibits reversible gel-sol transitions in response to both acid and base. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Warasawa M.,Tokyo University of Science | Kaijo A.,Idemitsu Kosan Co. | Sugiyama M.,Tokyo University of Science
Thin Solid Films | Year: 2012

The advantages of using indium zinc oxide (IZO) films instead of conventional Ga-doped zinc oxide (ZnO:Ga) films for Cu(In,Ga)Se 2 (CIGS) solar cells are described. The electrical properties of IZO are independent of film thickness. IZO films have higher mobility (30-40 cm 2/Vs) and lower resistivity (4-5 × 10 - 4 Ω cm) compared to ZnO:Ga films deposited without intentional heating, because the number of grain boundaries in amorphous IZO films is small. The properties of a CIGS solar cell using IZO at the window layer were better than those obtained using a conventional ZnO:Ga at the window layer; moreover, the properties tended to be independent of thickness. These results indicate that use of IZO as a transparent conducting oxide layer is expected to increase the efficiency of CIGS solar cells. © 2011 Elsevier B.V. All rights reserved.

Matsukawa T.,Tokyo University of Science | Kurita T.,Hiroshima University
Pattern Recognition | Year: 2012

This paper presents a novel image representation method for generic object recognition by using higher-order local autocorrelations on posterior probability images. The proposed method is an extension of the bag-of-features approach to posterior probability images. The standard bag-of-features approach is approximately thought of as a method that classifies an image to a category whose sum of posterior probabilities on a posterior probability image is maximum. However, by using local autocorrelations of posterior probability images, the proposed method extracts richer information than the standard bag-of-features. Experimental results reveal that the proposed method exhibits higher classification performances than the standard bag-of-features method. © 2011 Elsevier Ltd. All rights reserved.

Sternad D.,Northeastern University | Abe M.O.,Tokyo University of Science | Hu X.,Pennsylvania State University | Muller H.,Justus Liebig University
PLoS Computational Biology | Year: 2011

In motor tasks with redundancy neuromotor noise can lead to variations in execution while achieving relative invariance in the result. The present study examined whether humans find solutions that are tolerant to intrinsic noise. Using a throwing task in a virtual set-up where an infinite set of angle and velocity combinations at ball release yield throwing accuracy, our computational approach permitted quantitative predictions about solution strategies that are tolerant to noise. Based on a mathematical model of the task expected results were computed and provided predictions about error-tolerant strategies (Hypothesis 1). As strategies can take on a large range of velocities, a second hypothesis was that subjects select strategies that minimize velocity at release to avoid costs associated with signal- or velocity-dependent noise or higher energy demands (Hypothesis 2). Two experiments with different target constellations tested these two hypotheses. Results of Experiment 1 showed that subjects chose solutions with high error-tolerance, although these solutions also had relatively low velocity. These two benefits seemed to outweigh that for many subjects these solutions were close to a high-penalty area, i.e. they were risky. Experiment 2 dissociated the two hypotheses. Results showed that individuals were consistent with Hypothesis 1 although their solutions were distributed over a range of velocities. Additional analyses revealed that a velocity-dependent increase in variability was absent, probably due to the presence of a solution manifold that channeled variability in a task-specific manner. Hence, the general acceptance of signal-dependent noise may need some qualification. These findings have significance for the fundamental understanding of how the central nervous system deals with its inherent neuromotor noise. © 2011 Sternad et al.

Gao Z.,Tokyo University of Science | Zhi C.,Japan International Center for Materials Nanoarchitectonics | Bando Y.,Japan International Center for Materials Nanoarchitectonics | Golberg D.,Japan International Center for Materials Nanoarchitectonics | Serizawa T.,Tokyo University of Science
Journal of the American Chemical Society | Year: 2010

The isolation of individual boron nitride nanotubes (BNNTs) in aqueous phases has been achieved for the first time from raw materials based on the combination of peptide wrapping with a sonication procedure. Atomic force microscopic observations revealed the representative height and length of individual BNNTs. Fluorescence and infrared absorption spectra suggested the strong π-π interactions between BNNTs and the peptide. The absorption maxima of BNNTs were significantly blue-shifted from 200 nm for the original BNNTs to 193 nm. The modulation of the BNNT band gap with peptide wrapping promises potential applications of the peptide/BNNT complexes to various nanotechnologies. © 2010 American Chemical Society.

Provided is a magnesium-silicon composite material which contains Mg_(2)Si as an intermetallic compound imposing no burden on the environment, is suitable for use as a material for thermoelectric conversion modules, and has excellent thermoelectric conversion performance. The magnesium-silicon composite material has a dimensionless figure-of-merit parameter at 866K of 0.665 or larger. This magnesium-silicon composite material can have high thermoelectric conversion performance when used in, for example, a thermoelectric conversion module.

Showa KDE Co., Tokyo University of Science and Nippon Thermostat Co. | Date: 2011-12-28

A thermoelectric conversion material is provided which stably exhibits high thermoelectric conversion performance at about 300 to 600C and has high physical strength, resistance to weathering, durability, stability, and reliability. A method for manufacturing the same, and a thermoelectric conversion element are also provided. Also provided is a thermoelectric conversion material produced using, as a raw material, silicon sludge which has had to be disposed of in landfill. The thermoelectric conversion material of the invention is characterized by containing, as a main component, a sintered body composed of polycrystalline magnesium silicide containing at least one element selected from As, Sb, P, Al, and B. The manufacturing method uses purified and refined silicon sludge.

Umicore AG and Tokyo University of Science | Date: 2014-02-24

A sodium transition metal cathode material for a rechargeable sodium battery having a P2 layered bronze crystal structure, comprising at least 55 mol % manganese, wherein the manganese valence state is at least 3.75. The material undergoes a structural transformation to a secondary cathode material by extraction of sodium during the 1^(st )charge of a rechargeable sodium battery comprising the sodium cathode material. The material has either a composition Na_(x)MO_(2 )where M=Mn_(1-y-z)Li_(y)A_(z )where z<0.2 and y<0.33 and 0.66

Liu H.,ERATO JST | Newton G.J.,ERATO JST | Nakamura R.,University of Tokyo | Hashimoto K.,University of Tokyo | Nakanishi S.,Tokyo University of Science
Angewandte Chemie - International Edition | Year: 2010

Only connect: Members of genus Shewanella are Gram-negative bacteria that can utilize solid-state metal oxide as a terminal electron acceptor for respiration. The direct electrical connection between a single cell and a microelectrode is characterized by an optical tweezers technique (see picture; ITO=indium tin oxide). © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Amanov A.,Tokyo University of Science | Pyun Y.-S.,Sun Moon University | Sasaki S.,Tokyo University of Science
Tribology International | Year: 2014

This paper presents the effects of ultrasonic nanocrystalline surface modification (UNSM) technique on the tribological behavior of sintered Cu-based alloy prepared using a powder metallurgy (P/M) technique. The tribological behavior of the untreated and UNSM-treated specimens was investigated using a ball-on-disk reciprocating tribometer against a bearing steel ball under dry and oil-lubricated conditions. Results revealed that the UNSM-treated specimens led to a lower friction coefficient and higher wear resistance compared to the untreated specimens. The obtained results demonstrated the beneficial effects of UNSM technique. It is expected that the results of this study may be implemented to the automotive industry with the aim of improving the durability of internal combustion engine (ICE) parts which are made of Cu-based bimetal strips. © 2013 Elsevier Ltd. All rights reserved.

Ohtani N.,Tokyo University of Science | Ohtani N.,Cancer Institute | Ohtani N.,Japan Science and Technology Agency
Seminars in Immunopathology | Year: 2015

The human intestine is believed to contain approximately 100 trillion intestinal (gut) microbiota, comprising about 500–1000 different species. These intestinal microbiota exist in a symbiotic relationship with their host, by metabolizing compounds that the host is unable to utilize and controlling the immune balance of the host’s body. However, the composition of the intestinal microbiota is known to vary, depending on diet, nutrition status, and other factors. The recently developed meta-omics microbial data and the technical progress for the metabolome analysis provide a substantial understanding of the role of intestinal microbes and their metabolism. Interestingly, accumulating evidence suggests that the intestinal microbiota contributes to the onset of colorectal cancer, not only via the pro-carcinogenic activities of specific pathogens but also via the influence of the bacterial metabolites. Moreover, since the gut microbial metabolites circulate in the host’s body, it has been increasingly recognized that the intestinal microbiota are involved in the pathogenesis of diseases not only in the intestine but also in the organs located distant from the intestine. We recently found that metabolites from obesity-induced intestinal microbiota promoted liver cancer, and elucidated the underlying molecular mechanism. In this review, I first summarize the general understanding on the carcinogenic process by bacterial metabolites, and then discuss on the association between intestinal microbiota and colorectal cancer. In the last part, I will introduce our recent findings on liver cancer promotion by a metabolite of the obesity-induced intestinal microbiota. © 2014, Springer-Verlag Berlin Heidelberg.

Chung J.S.,University of Maryland, Baltimore | Zmora N.,University of Maryland, Baltimore | Katayama H.,Tokai University | Tsutsui N.,Tokyo University of Science
General and Comparative Endocrinology | Year: 2010

The removal of the eyestalk (s) induces molting and reproduction promoted the presence of regulatory substances in the eyestalk (ES), particularly medulla terminalis X-organ and the sinus gland (MTXO-SG). The PCR-based cloning strategies have allowed for isolating a great number of cDNAs sequences of crustacean hyperglycemic hormone (CHH) neuropeptides family from the eyestalk and non-eyestalk tissues, e.g., pericardial organs and fore- and hindguts. However, the translated corresponding neuropeptides in these tissues, their circulating concentrations, the mode of actions, and specific physiological functions have not been well described. The profiles of CHH neuropeptides present in the MTXO-SG may differ among decapod crustacean species, but they can be largely divided into two sub-groups on the basis of structural homology: (1) CHH and (2) molt-inhibiting hormone (MIH)/mandibular organ-inhibiting hormone (MOIH)/vitellogenesis/gonad-inhibiting hormone (V/GIH). CHH typically elevating the level of circulating glucose from animals under stressful conditions (hyper- and hypothermia, hypoxia, and low salinity) has multiple target tissues and functions such as ecdysteroidogenesis, osmoregulation, and vitellogenesis. Recently, MIH, known for exclusively suppressing ecdysteroidogenesis in Y-organs, is also reported to have an additional role in vitellogenesis of adult female crustacean species, suggesting that some CHH neuropeptides may acquire an extra regulatory role in reproduction at adult stage. This paper reviews the regulatory roles of CHH and MIH at the levels of specific functions, temporal and spatial expression, titers, their binding sites on the target tissues, and second messengers from two crab species: the blue crab, Callinectes sapidus, and the European green crab, Carcinus maenas. It further discusses the diverse regulatory roles of these neuropeptides and the functional plasticity of these neuropeptides in regard to life stage and species-specific physiology. © 2010 Elsevier Inc.

Sharma S.,Indian Institute of Technology Kanpur | Sharma S.,Tokyo University of Science
Journal of Colloid and Interface Science | Year: 2015

The water soluble glutathione capped metal nanoparticles (M-GS, where M=Pd, Pt, Au and Ag; GS=glutathione) with size 2.4±0.2nm were synthesized by borohydride reduction of metal ions in the presence of glutathione as capping ligand and used as catalyst for the hydrogenation of nitroaniline in aqueous phase. The rate of catalytic hydrogenation was dependent on metal type and the trend of catalytic activity over these M-GS nanoparticles was found to be Pd-GS (kapp=0.0227 (±3×10-4))s-1≫Pt-GS (kapp=0.0043 (±1×10-4))s-1>Au-GS (kapp=0.0015 (±0.2×10-4))s-1>Ag-GS (kapp=0.0008 (±0.2×10-4))s-1. The similar trend of catalytic activity was found for the hydrogenation of nitrobenzene. Our experimental results, along taking into account the theoretical calculations done by other research groups, suggest that the observed catalytic activity trend is attributed to the "different rates of H2 molecule adsorption and dissociation" on the M-GS nanoparticles. The "high rate of H2 molecule adsorption" and "highly oxidized surface" make Pd-GS nanoparticles an ideal candidate for the rapid hydrogenation. On the basis of our experimental results, we proposed that small gaps between less densely packed branched thiol "glutathione molecules" provide the access to metal nanoparticle surface for the hydrogenation reaction. © 2014 Elsevier Inc.

Ibrahim A.,Montpellier University | Ohshima H.,Tokyo University of Science | Allison S.A.,Georgia State University | Cottet H.,Montpellier University
Journal of Chromatography A | Year: 2012

In this paper, a systematic and comparative study related to the effective charge determination of three kinds of solutes (small ions, polyelectrolytes and nanoparticles) was performed. Four approaches were compared regarding their conditions of validity and their advantages/disadvantages. Three of them allow the effective charge determination from the electrophoretic mobility and the hydrodynamic radius of the solutes using electrophoretic mobility modelings based on Nernst-Einstein (NE), O'Brien-White-Ohshima (OWO) and Yoon and Kim (YK) equations. Electrophoretic mobility and hydrodynamic radius were determined by capillary electrophoresis and Taylor dispersion analysis, respectively, using the same instrumentation in similar conditions, on a large set of samples. A fourth experimental approach based on the sensitivity of detection in indirect UV detection mode (IUV) was compared to the previously mentioned methods. OWO and YK modelings are well adapted for the effective charge determination of small ions and nanoparticles, while IUV is the only method adapted for polyelectrolytes. © 2012 Elsevier B.V.

Okano K.,Tokyo University of Science | Taguchi M.,Nara Institute of Science and Technology | Fujiki M.,Nara Institute of Science and Technology | Yamashita T.,Tokyo University of Science
Angewandte Chemie - International Edition | Year: 2011

Sucked into the vortex: Hydrogels with embedded Rhodamine B dye showed stir-induced circularly polarized luminescence (CPL; see picture), the sense of which can be controlled by switching the stir direction from clockwise (CW) to counterclockwise (CCW) with slow cooling from the sol to gel states. The chiral alignment of the dye was erased by heating the sample above the gel-sol transition temperature. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Watanabe A.,Academia Sinica, Taiwan | Suzuki K.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

We present analyses on nucleon structure functions at small Bjorken x in the framework of holographic QCD. In this study, we improve the description of the target nucleon in the current setup of the holographic model by introducing a soft-wall AdS/QCD model, in which the anti-de Sitter geometry is smoothly cut off at the infrared boundary. Combining the improved Pomeron-nucleon coupling and the wave function of the five-dimensional U(1) vector field with the Brower-Polchinski-Strassler-Tan Pomeron exchange kernel, we obtain the structure functions. Here we focus on the nonperturbative kinematical region, where 10-6≤x≤10-2 and Q2≤ a few (GeV2), and show that our calculations for F2p and FLp are consistent with experimental data of the deep inelastic scattering at HERA. Furthermore, we find that the resulting longitudinal-to- transverse ratio of the structure functions, FLp/FTp, depends on both x and Q2. © 2014 American Physical Society.

Kawasaki Y.,Clinical Science Center | Miyaoka E.,Tokyo University of Science
Pharmaceutical Statistics | Year: 2013

In drug development, non-inferiority tests are often employed to determine the difference between two independent binomial proportions. Many test statistics for non-inferiority are based on the frequentist framework. However, research on non-inferiority in the Bayesian framework is limited. In this paper, we suggest a new Bayesian index τ = P(π1 > π2 - Δ0 | X1,X2), where X1 and X2 denote binomial random variables for trials n1 and n2, and parameters π1 and π2, respectively, and the non-inferiority margin is Δ0 > 0. We show two calculation methods for τ, an approximate method that uses normal approximation and an exact method that uses an exact posterior PDF. We compare the approximate probability with the exact probability for τ. Finally, we present the results of actual clinical trials to show the utility of index τ. Copyright © 2013 John Wiley & Sons, Ltd.

Sekiya R.,University of Tokyo | Sekiya R.,Ritsumeikan University | Fukuda M.,University of Tokyo | Kuroda R.,University of Tokyo | Kuroda R.,Tokyo University of Science
Journal of the American Chemical Society | Year: 2012

Although there are many examples of catenanes, those of more complex mechanically interlocked molecular architectures are rare. Additionally, little attention has been paid to the degradation of such interlocked systems into their starting complexes, although formation and degradation are complementary phenomena and are equally important. Interlocked metallohelicate, [(Pd 2L 4) 2] 8+ (2 8+), is a quadruply interlocked molecular architecture consisting of two mechanically interlocked monomers, [Pd 2L 4] 4+ (1 4+). 2 8+ has three internal cavities, each of which encapsulates one NO 3 - ion (1:3 host-guest complex, 2⊃(NO 3|NO 3|NO 3) 5+) and is characterized by unusual thermodynamic stability. However, both the driving force for the dimerization and the origin of the thermodynamic stability remain unclear. To clarify these issues, BF 4 -, PF 6 -, and OTf - have been used to demonstrate that the dimerization is driven by the anion template effect. Interestingly, the stability of 2 8+ strongly depends on the encapsulated anions (2⊃(NO 3|NO 3|NO 3) 5+ ≫ 2⊃(BF 4|BF 4|BF 4) 5+). The origins of this differing thermodynamic stability have been shown through detailed investigations to be due to the differences in the stabilization of the interlocked structure by the host-guest interaction and the size of the anion. We have found that 2-naphthalenesulfonate (ONs -) induces the monomerization of 2⊃(NO 3|NO 3|NO 3) 5+ via intermediate 2⊃(ONs|NO 3|ONs) 5+, which is formed by anion exchange. On the basis of this finding, and using p-toluenesulfonate (OTs -), the physical separation of 2⊃(NO 3|NO 3|NO 3) 5+ and 1 4+ as OTs - salt was accomplished. © 2012 American Chemical Society.

Hirakawa K.,University of Shizuoka | Segawa H.,Tokyo University of Science
Journal of Photochemistry and Photobiology A: Chemistry | Year: 2010

The solvent effects on an excitation energy transfer and a photo-induced electron transfer processes were examined using synthesized hydroxy(1-pyrenebutoxy)phosphorus(V)porphyrin. In the photoexcited state of the pyrene moiety, the intramolecular energy transfer to the porphyrin competed with the electron transfer from the pyrene to the porphyrin. The quantum yield of energy transfer in non-alcoholic solvents decreased with an increase of the solvent polarity due to the enhancement of electron transfer. However, the energy transfer was predominant process in alcoholic solvents with high polarity. The energy transfer yield increased with an increase in the ratio of methanol in the mixture of acetonitrile and methanol, of which solvent polarity is almost the same as that of acetonitrile. The redox potential measurements and ab initio molecular orbital calculation at Hartree-Fock 6-31G* level have shown that the electron affinity of the porphyrin moiety decreased through the hydrogen bonding with alcoholic solvents, resulting in that the electron transfer is suppressed and the excitation energy transfer becomes the predominant process. In conclusion, the hydrogen bonding interaction with alcoholic solvent contributes to the competition between energy and electron transfer by the changing of the energy level of charge transfer state rather than the effect of solvent polarity. © 2010 Elsevier B.V. All rights reserved.

Hirakawa K.,University of Shizuoka | Segawa H.,Tokyo University of Science
Photochemical and Photobiological Sciences | Year: 2010

Hydroxy(1-pyrenebutoxy)phosphorus(v) porphyrin was synthesized to investigate the competition process between intramolecular excitation energy transfer and electron transfer from the photo-excited pyrenyl group to the porphyrin ring. The absorption spectrum of the phosphorus(v) porphyrin moiety was blue-shifted depending on an increase in pH of the solvent (water-acetonitrile, 90/10, vol%/vol%), by the acid dissociation of the axial hydroxyl group. The acid dissociation constant was obtained from the absorption change and the pKa is estimated to be 9.5. In the photo-excited state of the pyrene moiety, the electron transfer competes with the energy transfer. The electron transfer is the predominant process (89%) and the energy transfer is suppressed in the hydroxyphosphorus(v) porphyrin with protonated hydroxyl group. The energy transfer yield increased depending on pH in a similar manner to the absorption change and become almost unity (98%) in the completely dissociated form of the hydroxyl group. In conclusion, the axial hydroxyl group connected at the central phosphorus atom of the porphyrin ring can be the switching site of these electron transition processes. © 2010 The Royal Society of Chemistry and Owner Societies.

Sano Y.,Tokyo University of Science | Watanabe W.,Ritsumeikan University | Matsunaga S.,Tokyo University of Science
Journal of Cell Science | Year: 2014

Chromophore-assisted laser or light inactivation (CALI) has been employed as a promising technique to achieve spatiotemporal knockdown or loss-of-function of target molecules in situ. CALI is performed using photosensitizers as generators of reactive oxygen species (ROS). There are two CALI approaches that use either transgenic tags with chemical photosensitizers, or genetically encoded fluorescent protein fusions. Using spatially restricted microscopy illumination, CALI can address questions regarding, for example, protein isoforms, subcellular localization or phase-specific analyses of multifunctional proteins that other knockdown approaches, such as RNA interference or treatment with chemicals, cannot. Furthermore, rescue experiments can clarify the phenotypic capabilities of CALI after the depletion of endogenous targets. CALI can also provide information about individual events that are involved in the function of a target protein and highlight them in multifactorial events. Beyond functional analysis of proteins, CALI of nuclear proteins can be performed to induce cell cycle arrest, chromatin- or locus-specific DNA damage. Even at organelle level - such as in mitochondria, the plasma membrane or lysosomes - CALI can trigger cell death. Moreover, CALI has emerged as an optogenetic tool to switch off signaling pathways, including the optical depletion of individual neurons. In this Commentary, we review recent applications of CALI and discuss the utility and effective use of CALI to address open questions in cell biology. © 2014. Published by The Company of Biologists Ltd.

Karkonen A.,University of Helsinki | Kuchitsu K.,Tokyo University of Science
Phytochemistry | Year: 2015

Although reactive oxygen species (ROS) are highly toxic substances that are produced during aerobic respiration and photosynthesis, many studies have demonstrated that ROS, such as superoxide anion radical (O2-) and hydrogen peroxide (H2O2), are produced in the plant cell wall in a highly regulated manner. These molecules are important signalling messengers playing key roles in controlling a broad range of physiological processes, such as cellular growth and development, as well as adaptation to environmental changes. Given the toxicity of ROS, especially of hydroxyl radical ('OH), the enzymatic ROS production needs to be tightly regulated both spatially and temporally. Respiratory burst oxidase homologues (Rboh) have been identified as ROS-producing NADPH oxidases, which act as key signalling nodes integrating multiple signal transduction pathways in plants. Also other enzyme systems, such as class III peroxidases, amine oxidases, quinone reductases and oxalate oxidases contribute to apoplastic ROS production, some especially in certain plant taxa. Here we discuss the interrelationship among different enzymes producing ROS in the plant cell wall, as well as the physiological roles of the ROS produced. © 2014 Elsevier Ltd. All rights reserved.

Fujita S.,State University of New York at Buffalo | Suzuki A.,Tokyo University of Science
Journal of Physics: Conference Series | Year: 2014

The quantum Hall effect (QHE) and high temperature superconductivity (HTSC) have remarkable common features. They occur only in two-dimensional (2D) solids. The critical temperature Tc of some HTSC exceeds 160K while the room temperature QHE is observed in graphene. The cause of both QHE and HTSC is the phonon exchange attraction. We develop a theoretical model for the QHE in terms of the composite bosons (fermions), each containing an electron and an odd (even) number of fluxons (magnetic flux quanta). The composite particles (boson, fermion) are bound by the phonon exchange attraction. If the Bose-Einstein condensation (BEC) of the composite (c)- bosons occurs, then the system exhibits zero resistivity and the associated Hall conductivity plateau. The Hall conductivity is calculated rigorously without averaging. The mystery of the fractional charge carried by the c-bosons is resolved in our model. © Published under licence by IOP Publishing Ltd.

Tokyo University of Science, Itoh Kikoh Co., Nippon Thermostat Co. and Swcc Showa Cable Systems Co. | Date: 2014-02-05

Provided is a heat storage device which can stably store heat by storing heat within a fixed temperature range. A heat storage device (10) of the present invention is characterized in being provided with a heat resistant frame (11), which is filled with one kind of alloy or mixed salt having a predetermined eutectic temperature, alternatively, a heat resistant frame (11), which is filled with two or more kinds of alloys or mixed salts having different eutectic temperatures, by having the alloys or the mixed salts adjacent to each other in the order of eutectic temperature levels with a partitioning wall (11a) therebetween. The heat storage device is also characterized in that the heat resistant frame (11) filled with the one kind of alloy or mixed salt having the predetermined eutectic temperature is set as a heat absorption-side heat storing section (12) and a heat dissipation-side heat storing section (13), alternatively, in the case where there are two or more kinds of alloys or mixed salts, the heat resistant frame (11) filled with an alloy (1) or a mixed salt (1) having a highest eutectic temperature is set as the heat absorption-side heat storing section (12), and that a heat resistant frame (11), which is filled with an alloy (2) or a mixed salt (2) having a lowest eutectic temperature is set as the heat dissipation-side heat storing section (13).

Tokyo University of Science, SWCC Showa Cable Systems Co., Nippon Thermostat Co. and Itoh Kikoh Co. | Date: 2012-03-30

Provided is a heat storage device which can stably store heat by storing heat within a fixed temperature range. A heat storage device (10) of the present invention is characterized in being provided with a heat resistant frame (11), which is filled with one kind of alloy or mixed salt having a predetermined eutectic temperature, alternatively, a heat resistant frame (11), which is filled with two or more kinds of alloys or mixed salts having different eutectic temperatures, by having the alloys or the mixed salts adjacent to each other in the order of eutectic temperature levels with a partitioning wall (11a) therebetween.

Tokyo University of Science and Nippon Thermostat Co. | Date: 2012-01-11

Provided is a thermoelectric conversion element which enables improvement in yield and durability, is easy to secure a temperature difference between the both ends and is easy to be bonded to an electrode without tilting, resulting in improvement of mass productivity. Also provided is a thermoelectric conversion module using the thermoelectric conversion element. [Solution] A thermoelectric conversion element 2 includes: a plurality of pole-shaped parts 22 with one ends of which being electrically connected to a first electrode 32, and the pole-shaped-parts 22 being arranged at an interval from each other; and a joining / connecting part 21 joining / connecting the other ends of the pole-shaped parts 22 together, and electrically connected to a second electrode 31. A connecting face 21b of the joining / connecting part 21, the face being connected to the second electrode 31, is larger than the sum total of areas of one ends 22a of the pole-shaped parts 22.

Nippon Thermostat Co. and Tokyo University of Science | Date: 2014-10-08

To improve the mass productivity of thermoelectric conversion modules. A thermoelectric conversion module 1 is equipped with a pair of substrates 11 and 12, a plurality of thermoelectric conversion elements 2, each having one end portion electrically connected to a first electrode 3 which is arranged on the substrate 11 and the other end portion electrically connected to a second electrode 4 which is arranged on the substrate 12, and a connection section 5 which electrically connects the first electrode 3 electrically connected to the thermoelectric conversion element 2 to the second electrode 4 electrically connected to an adjacent one of the thermoelectric conversion elements 2. The connection section 5 is separate from at least one of the first electrode 3 and the second electrode 4.

Harada Y.,Tokyo University of Science | Tanaka S.,University of Houston | Motomura Y.,Tokyo University of Science | Motomura Y.,RIKEN | And 6 more authors.
Immunity | Year: 2012

A main role for interleukin-4 (IL-4) is in humoral immunity, and follicular helper CD4 + T (Tfh) cells may be an intrinsic IL-4 source. Here we demonstrate that conserved noncoding sequence 2 (CNS2) is an essential enhancer element for IL-4 expression in Tfh cells but not in Th2 cells. Mice with a CNS2 deletion had a reduction in IgG1 and IgE production and in IL-4 expression in Tfh cells. Tracking of CNS2 activity via a GFP reporter mouse demonstrated that CNS2-active cells expressed several markers of Tfh cells: CXCR5, PD-1, and ICOS; the transcriptional master regulator Bcl6; and the cytokines IL-21 and IL-4. These CNS2-active cells were mainly localized in B cell follicles and germinal centers. The GFP + Tfh cells were derived from GFP - naive T cells after in vivo systemic immunization. These results indicate that CNS2 is an essential enhancer element required for IL-4 expression in Tfh cells controlling humoral immunity. © 2012 Elsevier Inc.

Hisamoto Y.,Tokyo University of Science | Kobayashi M.,Utsunomiya University
Plant Species Biology | Year: 2013

Two bamboo species, Phyllostachys meyeri McClure and Shibataea chinensis Nakai, which each originated from one clone cultivated in the Fuji Bamboo Garden, Japan, exhibited single-genet flowering and temporal changes in flowering and the regeneration process were investigated from 2004 to 2008 and from 2004 to 2011 in P. meyeri and S. chinensis, respectively. The clump of P. meyeri flowered when most mother culms were dead, followed by recovery with seedlings and survived rhizome system and a few culms continued to flower during 5 years, whereas S. chinensis flowered with mother culms alive, and most of the culms continued flowering in each spring until 2011. These processes were analyzed using expression levels of flowering promoting gene FLOWERING LOCUS T (FT) homologues and flowering repressing gene TERMINAL FLOWER 1/CENTRORADIALIS (TFL1/CEN) homologues by the quantitative real-time reverse transcription polymerase chain reaction method. The expression level of FT homologues was highest in the leaves during full bloom in both species, decreased gradually over the next 2years and vanished in 5 years in P. meyeri, but remained high for 3 years in S. chinensis. These results suggest that the expression level of FT homologues was related to flowering, irrespective of flowering behavior. Simultaneous expression of both genes was detected only in the inflorescences. The relationship between expression balance and flowering habit and inflorescence architecture is discussed. © 2012 The Society for the Study of Species Biology.

Iwashina K.,Tokyo University of Science | Iwase A.,Tokyo University of Science | Ng Y.H.,University of New South Wales | Amal R.,University of New South Wales | Kudo A.,Tokyo University of Science
Journal of the American Chemical Society | Year: 2015

Z-schematic water splitting was successfully demonstrated using metal sulfide photocatalysts that were usually unsuitable for water splitting as single particulate photocatalysts due to photocorrosion. When metal sulfide photocatalysts with a p-type semiconductor character as a H2-evolving photocatalyst were combined with reduced graphene oxide-TiO2 composite as an O2-evolving photocatalyst, water splitting into H2 and O2 in a stoichiometric amount proceeded. In this system, photogenerated electrons in the TiO2 with an n-type semiconductor character transferred to the metal sulfide through a reduced graphene oxide to achieve water splitting. Moreover, this system was active for solar water splitting. © 2014 American Chemical Society.

Imura Y.,Tokyo University of Science | Yoshimura E.,Tokyo University of Science | Sato K.,Gunma University
Analytical Chemistry | Year: 2013

Medicines are distributed to the whole body and excreted over time. A micromodel of the circulation-excretion system was developed to mimic these processes. This system comprised a dialysis part, a microperistaltic pump, and a target tissue. This microcirculation system was created on a microchip composed of a glass slide and polydimethylsiloxane sheets with microchannels fabricated by photolithography. A dialysis membrane was settled between two channels to form the dialysis part, and a pneumatic peristaltic pump was used to make the solution flow. The excretion and half-life of solute substances absorbed to albumin were changed according to their affinity to the protein. MCF-7 human breast cancer cells were cultured as target cells for drug samples, and the activities of anticancer agents were assayed using our system. Our data demonstrated that the anticancer activity of docetaxel or thio-TEPA could be assayed on the microcirculation-excretion chip. This system may allow for reduced consumption of cells and reagents compared to those required for conventional in vitro bioassay systems. © 2012 American Chemical Society.

Iwase A.,University of New South Wales | Ng Y.H.,University of New South Wales | Ishiguro Y.,Tokyo University of Science | Kudo A.,Tokyo University of Science | Amal R.,University of New South Wales
Journal of the American Chemical Society | Year: 2011

The effectiveness of reduced graphene oxide as a solid electron mediator for water splitting in the Z-scheme photocatalysis system is demonstrated. We show that a tailor-made, photoreduced graphene oxide can shuttle photogenerated electrons from an O2-evolving photocatalyst (BiVO4) to a H2-evolving photocatalyst (Ru/SrTiO3:Rh), tripling the consumption of electron - hole pairs in the water splitting reaction under visible-light irradiation. © 2011 American Chemical Society.

Tokyo University of Science, Mitsui Chemicals Inc. and Japan Atomic Energy Agency | Date: 2014-03-04

A new BiVO_(4)-laminate manufacturing method and BiVO_(4 )laminate are provided. A bismuth-vanadate laminate is manufactured as follows: a substrate that can be heated by microwaves is disposed inside a precursor solution containing a vanadium salt and a bismuth salt, microwave-activated chemical bath deposition (MW-CBD) is used to form a bismuth-vanadate layer on the substrate, and a firing process is performed as necessary. A bismuth-vanadate laminate manufactured in this way is suitable for use as a photocatalyst or photoelectrode.

Tokyo University of Science, Mitsui Chemicals Inc. and Japan Technological Research Association Of Artificial Photosynthetic Chemical Process | Date: 2016-01-13

A new BiVO_(4)-laminate manufacturing method and BiVO_(4) laminate are provided. A bismuth-vanadate laminate is manufactured as follows: a substrate that can be heated by microwaves is disposed inside a precursor solution containing a vanadium salt and a bismuth salt, microwave-activated chemical bath deposition (MW-CBD) is used to form a bismuth-vanadate layer on the substrate, and a firing process is performed as necessary. A bismuth-vanadate laminate manufactured in this way is suitable for use as a photocatalyst or photoelectrode.

Ng Y.H.,University of New South Wales | Iwase A.,University of New South Wales | Bell N.J.,University of New South Wales | Kudo A.,Tokyo University of Science | Amal R.,University of New South Wales
Catalysis Today | Year: 2011

Graphene-based semiconductors nanocomposites were synthesized via a single-step photocatalytic reduction process. UV active titanium dioxide (TiO2) and visible light driven photocatalysts (i.e. tungsten oxide (WO3) and bismuth vanadates (BiVO4)) with different conduction band energy levels were found efficient in transferring photogenerated electrons into graphene oxide (GO) thus reducing it to reduced graphene oxide (RGO). Simultaneously, nanocomposites of these particulate semiconductor and RGO sheet were obtained. X-ray photoelectron spectra revealed the 52-63% decrease in oxygen-containing carbon (hydroxyl and epoxy groups) of GO after illumination, indicating partial reduction of GO by excited photocatalysts. When made into thin films, photocurrent generation of these nanocomposites was enhanced by 160, 190 and 800%, respectively, for WO 3, TiO2 and BiVO4 as 5 wt% RGO was incorporated. These results demonstrate for the first time that a range of photocatalysts, not just TiO2, can be used to reduce and incorporate GO into nanocomposites that have higher photoelectrocatalytic efficiencies than their parent materials. © 2010 Elsevier B.V. All rights reserved.

Bojowald M.,Pennsylvania State University | Calcagni G.,Max Planck Institute for Physics | Tsujikawa S.,Tokyo University of Science
Physical Review Letters | Year: 2011

In the inflationary scenario of loop quantum cosmology in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to compare with observations. Since inverse-volume corrections can provide strong contributions to the running spectral indices, inclusion of terms higher than the second-order runnings in the power spectra is crucially important. Using the recent data of cosmic microwave background and other cosmological experiments, we place bounds on the quantum corrections. © 2011 American Physical Society.

Iwase H.,Tokyo University of Science | Endo H.,Tokyo University of Science | Katagiri M.,Japan Atomic Energy Agency | Shibayama M.,Tokyo University of Science
Journal of Applied Crystallography | Year: 2011

The small-angle neutron scattering spectrometer SANS-U at the research reactor (JRR-3) of the Japan Atomic Energy Agency, Tokai, Japan, has been successfully upgraded. This major upgrade was undertaken in order to install a high-resolution position-sensitive detector consisting of a cross-wired position-sensitive photomultiplier tube combined with a ZnS/6LiF scintillator on the SANS-U spectrometer. Without changing the total length of the spectrometer, the aim was to extend the accessible low-Q limit (Q is the magnitude of the scattering vector) and to shorten the measurement time by employing focusing small-angle neutron scattering (FSANS). By using both spherical MgF2 biconcave lenses and the new high-resolution position-sensitive detector, the accessible low-Q limit was extended from 2.5 10-3 to 3.8 10-4 Å-1. As a result, SANS-U can continuously cover a wide Q range from 3.8 10-4 to 0.35 Å-1 with a wavelength of 7 Å. FSANS can be utilized not only to improve the accessible low-Q limit but also to increase the intensity of incident neutrons passing through the sample in the conventional Q range from 2.5 10-3 to 0.35 Å-1. The use of high-intensity FSANS also allowed a reduction of the measuring time by approximately 1/3.16 by increasing the incident neutron intensity. © 2011 International Union of Crystallography Printed in Singapore - all rights reserved.

Bojowald M.,Pennsylvania State University | Calcagni G.,Max Planck Institute for Physics | Tsujikawa S.,Tokyo University of Science
Journal of Cosmology and Astroparticle Physics | Year: 2011

We study in detail the power spectra of scalar and tensor perturbations generated during inflation in loop quantum cosmology (LQC). After clarifying in a novel quantitative way how inverse-volume corrections arise in inhomogeneous settings, we show that they can generate large running spectral indices, which generally lead to an enhancement of power at large scales. We provide explicit formulæ for the scalar/tensor power spectra under the slow-roll approximation, by taking into account corrections of order higher than the runnings. Via a standard analysis, we place observational bounds on the inverse-volume quantum correction δa-σ (σ > 0, a is the scale factor) and the slow-roll parameter V for power-law potentials as well as exponential potentials by using the data of WMAP 7yr combined with other observations. We derive the constraints on δ for two pivot wavenumbers k0 for several values of δ. The quadratic potential can be compatible with the data even in the presence of the LQC corrections, but the quartic potential is in tension with observations. We also find that the upper bounds on δ(k0) for given σ and k0 are insensitive to the choice of the inflaton potentials. © 2011 IOP Publishing Ltd and SISSA.

Yoneda Y.,Japan Atomic Energy Agency | Kitanaka Y.,Tokyo University of Science | Noguchi Y.,Tokyo University of Science | Miyayama M.,Tokyo University of Science
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

The electronic structure of complex oxides is important for understanding their functional properties. Here, we report the results of investigating multiferroic BiFeO3 using various x-ray spectroscopy techniques. Zn- and Mn-codoped and Mn-doped BiFeO3 samples were prepared with the aim of improving ferroelectric properties of BiFeO3. The valences of the doped Mn and host Fe were investigated. When oxygen vacancies exist in the sample, Mn acts as a hole acceptor. Furthermore, Mn and Fe stabilize the perovskite unit by changing their ionic radius. As a result, Mn and Fe atoms exhibit various valence states in the BiFeO3 system. Evidence of the electronic structure for Fe 3d-O 2p-Bi 6s hybridization is also presented. © 2012 American Physical Society.

Krerkkaiwan S.,Chulalongkorn University | Fushimi C.,Tokyo University of Agriculture and Technology | Tsutsumi A.,Tokyo University of Science | Kuchonthara P.,Chulalongkorn University
Fuel Processing Technology | Year: 2013

In this work, the co-pyrolysis of Indonesian coal (sub-bituminous) and two types of biomass, rice straw and Leucaena leucocepha wood, was studied using a drop tube fixed-bed reactor. The gasification reactivity of the obtained co-pyrolyzed char with steam was examined using a rapid heating thermobalance reactor. In the co-pyrolysis, a synergetic effect, in terms of higher gas yield and lower tar and char yields, was manifested especially at a biomass and coal ratio of 1:1. This synergetic effect could be explained by the transferring of active OH and H radicals from the biomass to the coal as well as the catalytic role of potassium (K) from the biomass. In the steam gasification, the in situ pyrolyzed char from the coal/biomass blend exhibited a higher reactivity than that from the coal or the biomass. This could be related to the increased surface area and pore volume of chars from the blend as well as the influence of volatile K released from the biomass. In addition, the biomass type appeared to have a significant influence not only on the magnitude of the synergetic effect during the co-pyrolysis but also on the reactivity of the resultant chars. © 2013 Published by Elsevier B.V.

Cao X.,Dalian University of Technology | Cao X.,University of Paderborn | Ishida S.,Tokyo University of Science
Nonlinearity | Year: 2014

We consider a degenerate quasilinear Keller-Segel system of fully-parabolic type involving rotation in the aggregative term, ut = ∇ · (∇um - uS(u, v, x)∇v), (x, t) ∈ Ω × (0, T ), vt = Δv - uv, (x, t) ∈ Ω × (0, T ), ∇v · ν = 0, (∇um - uS(u, v, x)∇v) · ν = 0, x ∈ ∂Ω, t > 0 where Ω ⊂ ℝ2 is a bounded convex domain with smooth boundary. Here S(u, v, x) = (si,j)2×2 is a matrix with s i,j ∈ C1([0,∞) × [0,∞) × Ω). Moreover, |S(u, v, x)| < S̃(v) for all (u, v, x) ∈ [0,∞) × [0,∞) × Ω with S̃(v) nondecreasing on [0,∞). It is shown that whenever m > 1, for any nonnegative initial data, which is sufficiently smooth, the system possesses global and bounded weak solution. © 2014 IOP Publishing Ltd & London Mathematical Society.

Pena Ramirez J.,Tokyo University of Science | Aihara K.,Tokyo University of Science | Fey R.H.B.,TU Eindhoven | Nijmeijer H.,TU Eindhoven
Physica D: Nonlinear Phenomena | Year: 2014

A simplified model of the classical Huygens' experiment on synchronization of pendulum clocks is examined. The model consists of two pendula coupled by an elastically supported rigid bar. The synchronized limit behaviour of the system, i.e. in-phase and anti-phase synchronization of the pendula, is studied as a function of the stiffness of the spring that supports the coupling bar. It is demonstrated that the stiffness has a large influence on the existence, stability, and oscillation frequency of the in-phase solution. The relationship between the obtained results and experimental results that have been reported in the literature, including Huygens' original observations, is stressed. © 2013 Elsevier B.V. All rights reserved.

Kameyama K.,Ajinomoto Co. | Itoh K.,Tokyo University of Science
Microbes and Environments | Year: 2014

The aim of the present study was to identify bacteria that may contribute to the onset of metabolic dysfunctions. We isolated and identified a candidate bacterium belonging to Lachnospiraceae (strain AJ110941) in the feces of hyperglycemic obese mice. The colonization of germ-free ob/ob mice by AJ110941 induced significant increases in fasting blood glucose levels as well as liver and mesenteric adipose tissue weights, and decreases in plasma insulin levels and HOMA-β values. These results indicated that the specific gut commensal bacterium AJ110941 influenced the development of obesity and diabetes in ob/ob mice with genetic susceptibility for obesity. © 2014, Japanese Society of Microbial Ecology. All rights received.

Toshiba Corporation and Tokyo University of Science | Date: 2016-03-04

An amplifying circuit according to an embodiment includes a sample and hold circuit, an operational amplifier, a feedback capacitance, and a level shift circuit. The sample and hold circuit includes a sampling capacitance to sample an analog input signal in a sampling phase. The operational amplifier amplifies and outputs the analog input signal held by the sampling capacitance in the amplifying phase. The feedback capacitance is connected between the input terminal of the operational amplifier and the analog output terminal. The level shift circuit includes a level shift capacitance to sample the analog input signal in the sampling phase. A plurality of level shift capacitances is provided and connected in cascade between the output terminal of the operational amplifier and the analog output terminal.

Sapporo Medical University, Tokyo University of Science, Kyoto University and Sapporo Immuno Diagnostic Laboratory | Date: 2010-06-09

Abstract: Disclosed are: a composition and a method for the diagnosis and/or the treatment of a CSABP-related disease, the regulation of the proliferation of an RNA virus and the regulation of an RNA-metabolizing system, which targets a cyclosporine A-binding protein (CSABP); a method for the screening of a component that targets a CSABP; a composition and a method for the detection/inhibition of CsA, NS5B or cyclosphilin B by utilizing a CSABP; a promoter for a CSABP; a method for the screening of a substance capable of regulating the expression of a CSABP by utilizing the promoter; and a method for the determination of the occurrence or clinical stage of a CSABP-related disease.

Yamamoto D.,RIKEN | Sato C.,Tokyo University of Science | Nikuni T.,Tokyo University of Science | Tsuchiya S.,Tokyo University of Science
Physical Review Letters | Year: 2013

We study the superfluid state of atomic fermions in a tunable optical kagome lattice motivated by recent experiments. We show that the imposed superflow induces spatial modulations in the density and order parameter of the pair condensate and leads to a charge modulated superfluid state analogous to a supersolid state. The spatial modulations in the superfluid emerge due to the geometric effect of the kagome lattice that introduces anisotropy in hopping amplitudes of fermion pairs in the presence of superflow. We also study superflow instabilities and find that the critical current limited by the dynamical instability is quite enhanced due to the large density of states associated with the flatband. The charge modulated superfluid state can sustain high temperatures close to the transition temperature that is also enhanced due to the flatband and is therefore realizable in experiments. © 2013 American Physical Society.

Tabuchi Y.,Tokyo University of Science | Ishino S.,Tokyo University of Science | Ishikawa T.,Tokyo University of Science | Yamazaki R.,Tokyo University of Science | And 3 more authors.
Physical Review Letters | Year: 2014

We demonstrate large normal-mode splitting between a magnetostatic mode (the Kittel mode) in a ferromagnetic sphere of yttrium iron garnet and a microwave cavity mode. Strong coupling is achieved in the quantum regime where the average number of thermally or externally excited magnons and photons is less than one. We also confirm that the coupling strength is proportional to the square root of the number of spins. A nonmonotonic temperature dependence of the Kittel-mode linewidth is observed below 1 K and is attributed to the dissipation due to the coupling with a bath of two-level systems. © 2014 American Physical Society.

Park J.-H.,Tokyo University of Science | Katagiri T.,Tokushima University | Chung S.,Tokyo University of Science | Kijima K.,Tokyo University of Science | Nakamura Y.,Tokyo University of Science
Neoplasia | Year: 2011

A high expression of short and immature O-glycans is one of the prominent features of breast cancer cells, which would be attributed to the upregulated expression of glycosyltransferases. Therefore, a detailed elucidation of glycosyltransferases and their substrate(s)may improve our understandings for their roles inmammary carcinogenesis. Here we report that overexpression of polypeptide N-acetylgalactosaminyltransferase 6 (GALNT6), a glycosyltransferase involved in the initial step of O-glycosylation, has transformational potentials through disruptive acinar morphogenesis and cellular changes similar to epithelial-to-mesenchymal transition in normal mammary epithelial cell, MCF10A. As one of the critical O-glycan substrates, we identified fibronectin that was O-glycosylated in vivo and thereby stabilized by GALNT6. Because knockdown of fibronectin abrogated the disruptive proliferation caused by introduction of GALNT6 into epithelial cells, our findings suggest that GALNT6-fibronectin pathway should be a critical component for breast cancer development and progression. © 2011 Neoplasia Press, Inc.

Kurashige W.,Tokyo University of Science | Munakata K.,Tokyo University of Science | Nobusada K.,Japan Institute for Molecular Science | Negishi Y.,Tokyo University of Science
Chemical Communications | Year: 2013

A series of highly stable Cu-doped gold clusters with up to 9 Cu atoms per cluster, CunAu25-n(SeC8H17) 18, were synthesized using selenolate ligands. Spectroscopic analyses demonstrated that increasing levels of Cu doping in a cluster gradually decreased its HOMO-LUMO gap and consequently shifted its photoluminescence emission to longer wavelengths. These clusters were capable of exhibiting higher levels of Cu doping as compared to analogous clusters containing thiolate ligands. © 2013 The Royal Society of Chemistry.

Kurashige W.,Tokyo University of Science | Yamaguchi M.,Tokyo University of Science | Nobusada K.,Tokyo University of Science | Negishi Y.,Tokyo University of Science | Negishi Y.,Japan Institute for Molecular Science
Journal of Physical Chemistry Letters | Year: 2012

Thiolate-protected gold nanoclusters have attracted considerable attention as building blocks for new functional materials and have been extensively researched. Some studies have reported that changing the ligand of these gold nanoclusters from thiolate to selenolate increases cluster stability. To confirm this, in this study, we compare the stabilities of precisely synthesized [Au 25(SC 8H 17) 18] - and [Au 25(SeC 8H 17) 18] - against degradation in solution, thermal dissolution, and laser fragmentation. The results demonstrate that changing the ligand from thiolate to selenolate increases cluster stability in reactions involving dissociation of the gold-ligand bond but reduces cluster stability in reactions involving intramolecular dissociation of the ligand. These results reveal that using selenolate ligands makes it possible to produce gold clusters that are more stable against degradation in solution than thiolate-protected gold nanoclusters. © 2012 American Chemical Society.

Negishi Y.,Tokyo University of Science | Munakata K.,Tokyo University of Science | Ohgake W.,Tokyo University of Science | Nobusada K.,Japan Institute for Molecular Science
Journal of Physical Chemistry Letters | Year: 2012

Several recent studies have attempted to impart [Au 25(SR) 18] - with new properties by doping with foreign atoms. In this study, we studied the effect of copper doping on the electronic structure, geometric structure, and stability of [Au 25(SR) 18] - with the aim of investigating the effect of foreign atom doping of [Au 25(SR) 18] -. Cu nAu 25-n(SC 2H 4Ph) 18 was synthesized by reducing complexes formed by the reaction between metal salts (copper and gold salts) and PhC 2H 4SH with NaBH 4. Mass analysis revealed that the products contained Cu nAu 25-n(SC 2H 4Ph) 18 (n = 1-5) in high purity. Experimental and theoretical analysis of the synthesized clusters revealed that copper doping alters the optical properties and redox potentials of the cluster, greatly distorts its geometric structure, and reduces the cluster stability in solution. These findings are expected to be useful for developing design guidelines for functionalizing [Au 25(SR) 18] - through doping with foreign atoms. © 2012 American Chemical Society.

Negishi Y.,Tokyo University of Science | Kurashige W.,Tokyo University of Science | Niihori Y.,Tokyo University of Science | Nobusada K.,Japan Institute for Molecular Science
Physical Chemistry Chemical Physics | Year: 2013

Nanomaterials which exhibit both stability and functionality are currently considered to hold the most promise as components of nanotechnology devices. Thiolate (RS)-protected gold nanoclusters (Aun(SR)m) have attracted significant attention in this regard and, among these, the magic clusters are believed to be the best candidates since they are the most stable. We have investigated the effects of heteroatom doping, protection by selenolate ligands and protection by photoresponsive thiolates on the stability and physical/chemical properties of these clusters. Through such studies, we have attempted to establish methods of modifying magic Aun(SR)m clusters as a means of creating metal clusters that are both robust and functional. This paper summarizes our studies towards this goal and the obtained results. © 2013 the Owner Societies.

Asano M.,Tokyo University of Science | Ohya M.,Tokyo University of Science | Khrennikov A.,Linnaeus University
Foundations of Physics | Year: 2011

In experiments of games, players frequently make choices which are regarded as irrational in game theory. In papers of Khrennikov (Information Dynamics in Cognitive, Psychological and Anomalous Phenomena. Fundamental Theories of Physics, Kluwer Academic, Norwell, 2004; Fuzzy Sets Syst. 155:4-17, 2005; Biosystems 84:225-241, 2006; Found. Phys. 35(10):1655-1693, 2005; in QP-PQ Quantum Probability and White Noise Analysis, vol. XXIV, pp. 105-117, 2009), it was pointed out that statistics collected in such the experiments have "quantum-like" properties, which can not be explained in classical probability theory. In this paper, we design a simple quantum-like model describing a decision-making process in a two-players game and try to explain a mechanism of the irrational behavior of players. Finally we discuss a mathematical frame of non-Kolmogorovian system in terms of liftings (Accardi and Ohya, in Appl. Math. Optim. 39:33-59, 1999). © 2010 Springer Science+Business Media, LLC.

Negishi Y.,Tokyo University of Science | Igarashi K.,Tokyo University of Science | Munakata K.,Tokyo University of Science | Ohgake W.,Tokyo University of Science | Nobusada K.,Japan Institute for Molecular Science
Chemical Communications | Year: 2012

A phenylethanethiolate-protected Pd 2Au 36(SC 2H 4Ph) 24 cluster, which is a two-Pd atom-doped cluster of the well studied magic gold cluster Au 38(SC 2H 4Ph) 24, was synthesized in high purity and its stability was investigated. The results demonstrate that Pd 2Au 36(SC 2H 4Ph) 24 is more stable than Au 38(SC 2H 4Ph) 24 against degradation in solution and core etching by thiols. © 2012 The Royal Society of Chemistry.

Hashizume Y.,Tokyo University of Science | Suzuki M.,RIKEN
Physica A: Statistical Mechanics and its Applications | Year: 2013

We propose a new method to understand quantum entanglement using the thermo field dynamics (TFD) described by a double Hilbert space. The entanglement states show a quantum-mechanically complicated behavior. Our new method using TFD makes it easy to understand the entanglement states, because the states in the tilde space in TFD play a role of tracer of the initial states. For our new treatment, we define an extended density matrix on the double Hilbert space. From this study, we make a general formulation of this extended density matrix and examine some simple cases using this formulation. Consequently, we have found that we can distinguish intrinsic quantum entanglement from the thermal fluctuations included in the definition of the ordinary quantum entanglement at finite temperatures. Through the above examination, our method using TFD can be applied not only to equilibrium states but also to non-equilibrium states. This is shown using some simple finite systems in the present paper. © 2013 Elsevier B.V. All rights reserved.

Danshita I.,Tokyo University of Science | Danshita I.,RIKEN | Yamamoto D.,Waseda University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2010

We study superfluidity of supersolid phases of dipolar Bose gases in two-dimensional optical lattices. We perform linear stability analyses for the corresponding dipolar Bose-Hubbard model in the hard-core boson limit to show that a supersolid can have stable superflow until the flow velocity reaches a certain critical value. The critical velocity for the supersolid is found to be significantly smaller than that for a conventional superfluid phase. We propose that the critical velocity can be used as a signature to identify the superfluidity of the supersolid phase in experiment. © 2010 The American Physical Society.

Okada K.,University of Tokyo | Abe H.,RIKEN | Arimura G.-I.,Tokyo University of Science
Plant and Cell Physiology | Year: 2015

Jasmonic acid (JA) and its derivatives (jasmonates, JAs) are phytohormones with essential roles in plant defense against pathogenesis and herbivorous arthropods. Both the up-and down-regulation of defense responses are dependent on signaling pathways mediated by JAs as well as other stress hormones (e.g. salicylic acid), generally those involving the transcriptional and post-transcriptional regulation of transcription factors via protein modification and epigenetic regulation. In addition to the typical model plant Arabidopsis (a dicotyledon), advances in genetics research have made rice a model monocot in which innovative pest control traits can be introduced and whose JA signaling pathway can be studied. In this review, we introduce the dynamic functions of JAs in plant defense strategy using defensive substances (e.g. indole alkaloids and terpenoid phytoalexins) and airborne signals (e.g. green leaf volatiles and volatile terpenes) in response to biotrophic and necrotrophic pathogens as well as above-ground and below-ground herbivores. We then discuss the important issue of how the mutualism of herbivorous arthropods with viruses or bacteria can cause cross-talk between JA and other phytohormones to counter the defense systems. © 2014 The Author.

Yamaguchi Y.,Osaka University | Sogo T.,University of Rostock | Ito T.,Tokyo University of Science | Miyakawa T.,Aichi University of Education
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2010

We consider a uniform dipolar Fermi gas in two dimensions (2D) where the dipole moments of fermions are aligned by an orientable external field. We obtain the ground state of the gas in the Hartree-Fock approximation and investigate random-phase-approximation stability against density fluctuations of finite momentum. It is shown that the density-wave instability takes place in a broad region where the system is stable against collapse. We also find that the critical temperature can be a significant fraction of Fermi temperature for a realistic system of polar molecules. © 2010 The American Physical Society.

Negishi Y.,Tokyo University of Science | Kurashige W.,Tokyo University of Science | Niihori Y.,Tokyo University of Science | Iwasa T.,Japan Institute for Molecular Science | Nobusada K.,Japan Institute for Molecular Science
Physical Chemistry Chemical Physics | Year: 2010

A dodecanethiolate-protected Pd1 Au24 (SC 12H25) 18 cluster, which is a mono-Pd-doped cluster of the well understood magic gold cluster Au25 (SR) 18, was isolated in high purity using solvent fractionation and high-performance liquid chromatography (HPLC) after the preparation of dodecanethiolate-protected palladium-gold bimetal clusters. The cluster thus isolated was identified as the neutral [Pd1 Au24 (SC 12H25) 18]0 from the retention time in reverse phase columns and by elemental analyses. The LDI mass spectrum of [Pd1 Au24 (SC12H25) 18]0 indicates that [Pd1 Au 24(SC12H25) 18] 0 adopts a similar framework structure to Au25 (SR) 18, in which an icosahedral Au13 core is protected by six [-S-Au-S-Au-S-] oligomers. The optical absorption spectrum of [Pd1 Au24 (SC 12 H25)18]0 exhibits peaks at ∼690 and ∼620 nm, which is consistent with calculated results on [Pd1@Au24 (SC1H3) 18]0 in which the central gold atom of Au 25(SC1 H3) 18 is replaced with Pd. These results strongly indicate that the isolated [Pd1 Au 24 (SC12H25)18]0 has a core-shell [Pd1 Au24 (SC12H25) 18]0 structure in which the central Pd atom is surrounded by a frame of Au24(SC12 H25)18. Experiments on the stability of the cluster showed that Pd1@Au 24(SC12H25)18 is more stable against degradation in solution and laser dissociation than Au25(SC 12H25)18. These results indicate that the doping of a central atom is a powerful method to increase the stability beyond the Au25(SR)18 cluster. © the Owner Societies.

Kubo M.,Tokyo University of Science | Kubo M.,RIKEN | Motomura Y.,Tokyo University of Science
Frontiers in Immunology | Year: 2012

Although the major role of the immune response is host defense from a wide range of potentially pathogenic microorganisms, excess immune responses can result in severe host damage. The host thus requires anti-inflammatory mechanisms to prevent reactivity to self. Interleukin-10 (IL-10) is a cytokine with broad anti-inflammatory properties involved in the pathogenesis of various diseases. IL-10 was originally described as a T helper (TH2) derived cytokine, but further studies indicated that IL-10 is expressed not only by many cells of the adaptive immune system, including T and B cells, but also by the innate immune cells, including dendritic cells (DCs), macrophages, mast cells, and natural killer (NK) cells. In addition, IL-10 can be induced in TH1 and TH17 cells by chronic inflammation as a system of feedback regulation. In this review, we focus on the molecular mechanisms underlying IL10 gene expression in adaptive immune cells and summarize the recent progresses in epigenetic and transcriptional regulation of the IL10 gene. Understanding the transcriptional regulatory events may help in the development of new strategies to control inflammatory diseases. © 2012 Kubo and Motomura.

Tominaga-Wada R.,University of Miyazaki | Ishida T.,Tokyo University of Science | Wada T.,RIKEN
International Review of Cell and Molecular Biology | Year: 2011

Epidermis cell differentiation in Arabidopsis thaliana is a model system for understanding the mechanisms leading to the developmental end state of plant cells. Both root hairs and trichomes differentiate from epidermal cells and molecular genetic analyses using Arabidopsis mutants have demonstrated that the differentiation of root hairs and trichomes is regulated by similar molecular mechanisms. Molecular-genetic approaches have led to the identification of many genes that are involved in epidermal cell differentiation, most of which encode transcription factors that induce the expression of genes active in both root hair and trichome development. Control of cell growth after fate determination has also been studied using Arabidopsis mutants. © 2011 Elsevier Inc.

Tatara G.,RIKEN | Fukuyama H.,Tokyo University of Science
Journal of the Physical Society of Japan | Year: 2014

Excitations of two-dimensional skyrmion lattice are theoretically studied based on a collective coordinate description. Starting from the representation of skyrmion lattice in terms of three helices, we identify the canonical coordinates describing low energy excitations as phasons. The phason excitation spectra turn out to have one gapless mode with a quadratic dispersion and one massive mode, in agreement with previous studies. We will show that there is another collective mode governing the topological nature and the stability of skyrmion lattice and that the fluctuation of this mode leads to a screening of the topological charge of the lattice. Experimental implications of the screening effect in microwave absorption, topological Hall effect and depinning threshold current in metals are discussed. © 2014 The Physical Society of Japan.

Ishizuka T.,Tokyo University of Science | Ishizuka T.,RIKEN | Xu Y.,University of Miyazaki | Komiyama M.,Tokyo University of Science | Komiyama M.,University of Tsukuba
Journal of the American Chemical Society | Year: 2013

The understanding of telomeres is expected to provide major insights into genome stability, cancer, and telomere-related diseases. In recent years, there have been considerable improvements in the technologies available to determine the length of telomeres of human chromosomes; however, the present methods for measuring telomere length are fraught with shortcomings that have limited their use. Here we describe a method for detection of individual telomere lengths (DITL) that uses a chemistry-based approach that accurately measures the telomere lengths from individual chromosomes. The method was successfully used to determine telomere DNA by breaking in the target sequence and producing a "real telomere fragment." The DITL approach involves cleavage of the sequence adjacent to the telomere followed by resolution of the telomere length at the nucleotide level of a single chromosome. Comparison of the DITL method and the traditional terminal restriction fragment (TRF) analysis indicates that the DITL approach appears to be promising for the quantification of telomere repeats in each chromosome and the detection of accurate telomere lengths that can be missed using TRF analysis. © 2012 American Chemical Society.

Takiyama K.,Tokyo University of Science | Okada M.,Tokyo University of Science | Okada M.,RIKEN
PLoS Computational Biology | Year: 2012

Many redundancies play functional roles in motor control and motor learning. For example, kinematic and muscle redundancies contribute to stabilizing posture and impedance control, respectively. Another redundancy is the number of neurons themselves; there are overwhelmingly more neurons than muscles, and many combinations of neural activation can generate identical muscle activity. The functional roles of this neuronal redundancy remains unknown. Analysis of a redundant neural network model makes it possible to investigate these functional roles while varying the number of model neurons and holding constant the number of output units. Our analysis reveals that learning speed reaches its maximum value if and only if the model includes sufficient neuronal redundancy. This analytical result does not depend on whether the distribution of the preferred direction is uniform or a skewed bimodal, both of which have been reported in neurophysiological studies. Neuronal redundancy maximizes learning speed, even if the neural network model includes recurrent connections, a nonlinear activation function, or nonlinear muscle units. Furthermore, our results do not rely on the shape of the generalization function. The results of this study suggest that one of the functional roles of neuronal redundancy is to maximize learning speed. © 2012 Takiyama, Okada.

Barrat J.-A.,CNRS Oceanic Domains Laboratory | Yamaguchi A.,Japan National Institute of Polar Research | Yamaguchi A.,Tokyo University of Science
Meteoritics and Planetary Science | Year: 2014

Mandler and Elkins-Tanton recently proposed an upgraded magma ocean model for the differentiation history of the giant asteroid 4 Vesta. They show that a combination of both equilibrium crystallization and fractional crystallization processes can reproduce the major element compositions of eucritic melts and broadly the range of mineral compositions observed in diogenites. They assert that their model accounts for all the howardites, eucrites, and diogenites (HEDs), and use it to predict the crustal thickness and the proportions of the various lithologies. Here, we show that their model fails to explain the trace element diversity of the diogenites, contrary to their claim. The diversity of the heavy REE enrichment exhibited by the orthopyroxenes in diogenites is inconsistent with crystallization of these cumulates in either shallow magma chambers replenished by melts from a magma ocean or in a magma ocean. Thus, proportions of the various HED lithologies and the crustal thickness predicted from this model are not necessarily valid. © The Meteoritical Society, 2014.

Ribierre J.-C.,RIKEN | Watanabe S.,Tokyo University of Science | Matsumoto M.,Tokyo University of Science | Muto T.,RIKEN | And 2 more authors.
Advanced Materials | Year: 2010

Solution-processed organic field-effect transistors based on the ambipolar quinoidal oligothiophene [QQT(CN)4] show either p- or n-type dominant behavior depending on the solvent used for the spin-coating of the semiconducting organic thin film. In addition, majority carrier type conversion from n-type to ambipolar is achieved by solvent vapor treatment. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tokyo University of Science and Kunimine Industries Co. | Date: 2012-03-29

An agent for searching for protein crystallization conditions, containing a water-swellable layered silicate having a fluorine atom and a hydroxyl group, wherein the fluorine atom is covalently bonded to the silicate by isomorphous substitution with the hydroxyl group. A method of searching for protein crystallization conditions, which comprises a step of mixing the agent for searching for protein crystallization conditions described above and a solution in which a protein is dissolved.

Kunimine Industries Co. and Tokyo University of Science | Date: 2014-02-05

{Problems} To provide an agent that is used for searching protein crystallization conditions, and has improved properties of promoting protein crystal formation and improved operability, and a method for searching for protein crystallization conditions using the same. {Means to solve} An agent for searching for protein crystallization conditions, containing a water-swellable layered silicate having a fluorine atom and a hydroxyl group, wherein the fluorine atom is covalently bonded to the silicate by isomorphous substitution with the hydroxyl group. A method of searching for protein crystallization conditions, which comprises a step of mixing the agent for searching for protein crystallization conditions described above and a solution in which a protein is dissolved.

Tokushima University, Morita Pharmaceutical Ind. Ltd. and Tokyo University of Science | Date: 2013-07-10

This invention provides a Gc globulin derivative that can be easily produced from Gc globulin and can be used as GcMAF. This invention also provides degalactosylated Gc globulin obtained by processing Gc globulin with -galactosidase.

Kurashige W.,Tokyo University of Science | Niihori Y.,Tokyo University of Science | Sharma S.,Tokyo University of Science | Negishi Y.,Tokyo University of Science | Negishi Y.,Japan Institute for Molecular Science
Journal of Physical Chemistry Letters | Year: 2014

Nanomaterials that exhibit both stability and functionality are currently considered to hold great promise as components of nanotechnology devices. Thiolate-protected gold clusters (Aun(SR)m) have long attracted attention as functional nanomaterials. Magic Aun(SR)m clusters are an especially stable group of thiolate-protected clusters that have particularly high potential as functional materials. Although numerous application experiments have been conducted for magic Aun(SR)m clusters, it is important that functionalization methods are also established to allow for effective utilization of these materials. The results of recent research on heteroatom doping and the use of other chalcogenide ligands strongly suggest that these strategies are promising as functionalization methods of magic Aun(SR)m clusters. In this Perspective, we focus on studies relating to three representative types of magic clusters-Au25(SR)18, Au38(SR)24, and Au144(SR)60-and discuss the recent progress and future issues. © 2014 American Chemical Society.

Fukagawa H.,Japan Broadcasting Corporation NHK | Shimizu T.,Japan Broadcasting Corporation NHK | Hanashima H.,Tokyo University of Science | Osada Y.,Tokyo University of Science | And 2 more authors.
Advanced Materials | Year: 2012

Highly efficient and stable, red phosphorescent organic light-emitting diodes (OLEDs) are demonstrated using platinum complexes. The host/dopant combination is a crucial factor in obtaining high efficiency and stability. The OLEDs exhibit a maximum external quantum efficiency of about 20% and an expected half-life of about 10 000 h with an initial luminance of 1000 cd m -2. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Misumi M.,Waseda University | Katoh H.,Mie University | Tomo T.,Tokyo University of Science | Sonoike K.,Waseda University
Plant and Cell Physiology | Year: 2016

Although the photosynthetic reaction center is well conserved among different cyanobacterial species, the modes of metabolism, e.g. respiratory, nitrogen and carbon metabolism and their mutual interaction, are quite diverse. To explore such uniformity and diversity among cyanobacteria, here we compare the influence of the light environment on the condition of photosynthetic electron transport through Chl fluorescence measurement of six cyanobacterial species grown under the same photon flux densities and at the same temperature. In the dark or under weak light, up to growth light, a large difference in the plastoquinone (PQ) redox condition was observed among different cyanobacterial species. The observed difference indicates that the degree of interaction between respiratory electron transfer and photosynthetic electron transfer differs among different cyanobacterial species. The variation could not be ascribed to the phylogenetic differences but possibly to the light environment of the original habitat. On the other hand, changes in the redox condition of PQ were essentially identical among different species at photon flux densities higher than the growth light. We further analyzed the response to high light by using a typical energy allocation model and found that 'non-regulated' thermal dissipation was increased under high-light conditions in all cyanobacterial species tested. We assume that such 'non-regulated' thermal dissipation may be an important 'regulatory' mechanism in the acclimation of cyanobacterial cells to high-light conditions. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved.

Torigoe H.,Tokyo University of Science | Ono A.,Kanagawa University | Kozasa T.,Tokyo University of Science
Chemistry - A European Journal | Year: 2010

Metal-mediated base pair formation, resulting from the interaction between metal ions and artificial bases in oligonucleotides, has been developed for its potential application in nanotechnology. We have recently found that the T:T mismatched base pair binds with HgII ions to generate a novel metal-mediated base pair in duplex DNA. The thermal stability of the duplex with the T-Hg-T base pair was comparable to that of the corresponding T:A or A:T. The novel T-Hg-T base pair involving the natural base thymine is more convenient than the metal-mediated base pairs involving artificial bases due to the lack of time-consuming synthesis. Here, we examine the specificity and thermodynamic properties of the binding between HgII ions and the T:T mismatched base pair. Only the melting temperature of the duplex with T:T and not of the perfectly matched or other mismatched base pairs was found to specifically increase in the presence of HgII ions. HgII specifically bound with the T:T mismatched base pair at a molar ratio of 1:1 with a binding constant of 106 M-1, which is significantly higher than that for nonspecific metal ion-DNA interactions. Furthermore, the higher-order structure of the duplex was not significantly distorted by the HgII ion binding. Our results support the idea that the T-Hg-T base pair could eventually lead to progress in potential applications of metal-mediated base pairs in nanotechnology. Mercury rising: We have investigated the binding mode between HgII ions and the T:T mismatched base pair. HgII ions surrounded by structured water molecules can be dehydrated, and the two protons at the N3 positions of T:T can then be released, as shown in the scheme. Dehydrated HgII ions can then bind with the deprotonated thymine bases to form N3-Hg-N3. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wu L.,Vanderbilt University | Parekh V.V.,Vanderbilt University | Hsiao J.,Vanderbilt University | Kitamura D.,Tokyo University of Science | Van Kaer L.,Vanderbilt University
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Lipid accumulation in obesity triggers a low-grade inflammation that results from an imbalance between pro- and anti-inflammatory components of the immune system and acts as the major underlying mechanism for the development of obesity-associated diseases, notably insulin resistance and type 2 diabetes. Innate-like B cells are a subgroup of B cells that respond to innate signals and modulate inflammatory responses through production of immunomodulatory mediators such as the anti-inflammatory cytokine IL-10. In this study, we examined innate-like B cells in visceral white adipose tissue (VAT) and the relationship of these cells with their counterparts in the peritoneal cavity and spleen during diet-induced obesity (DIO) in mice. We show that a considerable number of innate-like B cells bearing a surface phenotype distinct from the recently identified "adipose natural regulatory B cells" populate VAT of lean animals, and that spleen represents a source for the recruitment of these cells in VAT during DIO. However, demand for these cells in the expanding VAT outpaces their recruitment during DIO, and the obese environment in VAT further impairs their function. We further show that removal of splenic precursors of innate-like B cells through splenectomy exacerbates, whereas supplementation of these cells via adoptive transfer ameliorates, DIO-associated insulin resistance. Additional adoptive transfer experiments pointed toward a dominant role of IL-10 in mediating the protective effects of innate-like B cells against DIO-induced insulin resistance. These findings identify spleen-supplied innate-like B cells in VAT as previously unrecognized players and therapeutic targets for obesity-associated diseases. © 2014, National Academy of Sciences. All rights reserved.

Shimogawa Y.,Waseda University | Sakuma Y.,Tokyo University of Science | Yamanouchi K.,Waseda University
Neuroscience Research | Year: 2015

Neural connections of the ventromedial hypothalamic nucleus (VMN) to and from forebrain and midbrain structures, which are involved in the neuroendocrine regulation of reproduction, were investigated. A retrograde (fluoro-gold [FG]) or an anterograde neural tracer (phaseolus vulgaris-leucoagglutinin [PHA-L]) was injected into the left side of the VMN in ovariectomized rats. Six days after injection with FG or 11 days after injection with PHA-L, brains were fixed and sectioned. After immunohistochemistry, digital images of FG-labeled neural cell bodies (FG-cells) or PHA-L-labeled fibers (PHA-L-fibers) were analyzed. Injection sites of FG and PHA-L were mainly in the ventrolateral VMN. Considerable numbers of FG-cells and PHA-L-fibers were present in the left side of the medial amygdala, ventral lateral septum, preoptic area, bed nucleus of stria terminalis, dorsomedial hypothalamic nucleus, arcuate nucleus, periventricular nucleus of thalamus, and midbrain central gray. The lateral dorsal raphe nuclei contained many PHA-L-fibers but few FG-cells. By contrast, both sides of the median raphe nucleus contained many FG-cells but few PHA-L-fibers. Reciprocal direct neural connection between the right and left side of the VMN were observed. The present results provide an anatomical basis for functional relationships between the VMN and these nuclei. © 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society.

Ochiai T.,Kanagawa Academy Of Science And Technology | Ochiai T.,Tokyo University of Science | Fujishima A.,Kanagawa Academy Of Science And Technology | Fujishima A.,Tokyo University of Science
Journal of Photochemistry and Photobiology C: Photochemistry Reviews | Year: 2012

In view of the situation that environmental issues become more serious day by day, recent studies on practical applications of TiO2 photocatalysis for environmental purification are reviewed. Although the fundamental aspects and the mechanisms of TiO2 photocatalysis have recently become quite well understood, effective photocatalytic environmental purifier, especially water purifier, could not be developed to the stage of real industrial technology. The removal rate of gaseous or aqueous contaminants is influenced by numerous parameters; UV light intensity, substrate concentration, O2 partial pressure, humidity, substrate type, and so on. Moreover, TiO2 photocatalyst essentially has a difficulty in decomposition of large amount of contaminants or refractory chemicals. As the solutions of these problems, combination with other processes such as advanced oxidation processes and improvement of the design of photocatalytic environmental purification systems are described. During the past several years, the strategies for effective design of the system are well discussed and evaluated. The reactor design for air- or water-purification can be classified into two main strategies: (1) enlargement of reactive surface area and (2) improvement of mass transfer. Based on these insights, very recent achievements for development of photocatalytic environmental purification system with our contribution in each aspect and future research directions are reviewed. © 2012 Elsevier B.V.

Nakata K.,Kanagawa Academy Of Science And Technology | Nakata K.,Tokyo University of Science | Fujishima A.,Kanagawa Academy Of Science And Technology | Fujishima A.,Tokyo University of Science
Journal of Photochemistry and Photobiology C: Photochemistry Reviews | Year: 2012

TiO 2 photocatalysis is widely used in a variety of applications and products in the environmental and energy fields, including self-cleaning surfaces, air and water purification systems, sterilization, hydrogen evolution, and photoelectrochemical conversion. The development of new materials, however, is strongly required to provide enhanced performances with respect to the photocatalytic properties and to find new uses for TiO 2 photocatalysis. In this review, recent developments in the area of TiO 2 photocatalysis research, in terms of new materials from a structural design perspective, have been summarized. The dimensionality associated with the structure of a TiO 2 material can affect its properties and functions, including its photocatalytic performance, and also more specifically its surface area, adsorption, reflectance, adhesion, and carrier transportation properties. We provide a brief introduction to the current situation in TiO 2 photocatalysis, and describe structurally controlled TiO 2 photocatalysts which can be classified into zero-, one-, two-, and three-dimensional structures. Furthermore, novel applications of TiO 2 surfaces for the fabrication of wettability patterns and for printing are discussed. © 2012 Elsevier B.V.

Modesto L.,Fudan University | Tsujikawa S.,Tokyo University of Science
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2013

We present a general covariant action for massive gravity merging together a class of "non-polynomial" and super-renormalizable or finite theories of gravity with the non-local theory of gravity recently proposed by Jaccard, Maggiore and Mitsou (Phys. Rev. D 88 (2013) 044033). Our diffeomorphism invariant action gives rise to the equations of motion appearing in non-local massive gravity plus quadratic curvature terms. Not only the massive graviton propagator reduces smoothly to the massless one without a vDVZ discontinuity, but also our finite theory of gravity is unitary at tree level around the Minkowski background. We also show that, as long as the graviton mass m is much smaller the today's Hubble parameter H0, a late-time cosmic acceleration can be realized without a dark energy component due to the growth of a scalar degree of freedom. In the presence of the cosmological constant Λ, the dominance of the non-local mass term leads to a kind of "degravitation" for Λ at the late cosmological epoch. © 2013 Elsevier B.V.

Arahata E.,Tokyo University of Science | Nikuni T.,Tokyo University of Science | Griffin A.,University of Toronto
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

In Bose superfluids, the single-particle Green's function can be directly related to the superfluid velocity-velocity correlation function in the hydrodynamic regime. An explicit expression for the single-particle spectral density was originally written down by Hohenberg and Martin in 1965, starting from the two-fluid equations for a superfluid. We give a simple derivation of their results. Using these results, we calculate the relative weights of first and second sound modes in the single-particle spectral density as a function of temperature in a uniform Bose gas. We show that the second sound mode makes a dominant contribution to the single-particle spectrum in a relatively high-temperature region. We also discuss the possibility of experimental observation of the second sound mode in a Bose gas by photoemission spectroscopy. © 2011 American Physical Society.

Latthe S.S.,Tokyo University of Science | Terashima C.,Tokyo University of Science | Nakata K.,Tokyo University of Science | Sakai M.,Kanagawa Academy Of Science And Technology | Fujishima A.,Tokyo University of Science
Journal of Materials Chemistry A | Year: 2014

Optically transparent, mechanically durable, and self-cleaning superhydrophobic coatings are greatly awaited for applications in daily life. An attempt has been made to develop sol-gel processed semi-transparent, durable and self-cleaning superhydrophobic coatings on glass using a silica-PMMA composite. A water drop acquires a near spherical shape on the coating exhibiting a water contact angle of ∼159° and immediately rolled off under small disturbance. A 10 μl water drop could individually collect around 10 mg of dirt particles along the way whilst rolling off the coating surface. The superhydrophobicity of the coatings remained intact under the impact of a water jet. A water jet hits the superhydrophobic coating and was repelled straightaway off the surface, without leaving any trace of water. These coatings showed both strong superhydrophobicity and superoleophilicity. We observed an improvement in mechanical stability, as well as optical transparency of the coatings in the visible range after low loadings of PMMA polymer (2 vol%) in silica. The prepared coatings maintained excellent superhydrophobicity even after 6 months storage under normal conditions in air. © 2014 the Partner Organisations.

Sawai H.,Waseda University | Yamada S.,Waseda University | Suzuki H.,Tokyo University of Science
Astrophysical Journal Letters | Year: 2013

We performed the first global numerical simulations of magnetorotational instability from a sub-magnetar-class seed magnetic field in core-collapse supernovae. As a result of axisymmetric ideal MHD simulations, we found that the magnetic field is greatly amplified to magnetar-class strength. In the saturation phase, a substantial part of the core is dominated by turbulence, and the magnetic field possesses dominant large-scale components, comparable to the size of a proto-neutron star. A pattern of coherent channel flows, which generally appears during the exponential growth phase in previous local simulations, is not observed in our global simulations. While the approximate convergence in the exponential growth rate is attained by increasing spatial resolution, that of the saturation magnetic field is not achieved due to still large numerical diffusion. Although the effect of the magnetic field on the dynamics is found to be mild, a simulation with a high enough resolution might result in a larger impact. © 2013. The American Astronomical Society. All rights reserved.

Briscese F.,Instituto Nazionale Of Alta Matematica Francesco Severi | Briscese F.,University of Rome La Sapienza | Modesto L.,Fudan University | Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

The recent Planck data of cosmic microwave background temperature anisotropies support the Starobinsky theory in which the quadratic Ricci scalar drives cosmic inflation. We build up a multidimensional quantum consisted ultraviolet completion of the model in a phenomenological "bottom-up approach." We present the maximal class of theories compatible with unitarity and (super-)renormalizability or finiteness which reduces to the Starobinsky theory in the low-energy limit. The outcome is a maximal extension of the Krasnikov-Tomboulis-Modesto theory including an extra scalar degree of freedom besides the graviton field. The original theory was afterwards independently discovered by Biswas-Gerwick-Koivisto-Mazumdar starting from first principles. We explicitly show power counting super-renormalizability or finiteness (in odd dimensions) and unitarity (no ghosts) of the theory. Any further extension of the theory is nonunitary, confirming the existence of at most one single extra degree of freedom, the scalaron. A mechanism to achieve the Starobinsky theory in string (field) theory is also investigated at the end of the paper. © 2014 American Physical Society.

Maeda J.,Tokyo University of Science | Kimura K.,Tokyo University of Science | Ebisawa S.,Waseda University
Journal of Lightwave Technology | Year: 2014

Effects of fiber dispersion on the radio-over-fiber (RoF) transmission of a microwave signal are experimentally demonstrated when deep optical modulation is employed. In a previous paper (J. Lightwave Technol., vol. 30, pp. 2625-2632, Aug. 2012), the authors analytically predicted that harmonics of sidebands generated by the nonlinear response of optical modulators would contribute to the cyclic variation of the signal amplitude other than by dispersion-induced fading. To confirm this prediction, we set up an RoF link that transmitted a 16-quadrature amplitude modulation microwave signal, and we observed changes in the constellation map. Experiments were conducted both for optical double-sideband (ODSB) signals and optical single-sideband plus carrier (OSSB+C) signals. In the ODSB case, outer symbols in the constellation map moved slightly outwards as the signal propagated down the fiber. If we eliminated the harmonic sidebands by using an optical filter, the movement was reversed; this was probably due to the residual chirp in the LN modulator. In the OSSB+C case, we observed a similar movement but also a slight phase rotation that depended on the amplitude of the symbol. These observations qualitatively agree with our predictions. © 2012 IEEE.

Tokyo University of Science and Kokusan Chemical Co. | Date: 2014-10-02

[Problems] To provide a novel peptide synthesis technique that is completely different than heretofore, and to provide a novel compound that enables the synthesis/creation of a novel artificial functional protein and the synthesis/creation of a novel functional peptide, as well as a method for producing the same. [Solution] A compound represented by formula (I) or a salt thereof.

Disclosed is an aluminum-magnesium-silicon composite material that contains an alloy comprising Al, Mg, and Si and can be used favorably as a material for a thermoelectric conversion module, and that has excellent thermoelectric conversion properties. The aluminum-magnesium-silicon composite material contains an alloy comprising Al, Mg and Si, and has an electrical conductivity () of 1000-3000 S/cm at 300 K. This aluminum-magnesium-silicon composite material is favorable in the production of a thermoelectric exchange element as a result of having excellent thermoelectric conversion properties.

Hisamatsu Y.,Tokyo University of Science | Aoki S.,Tokyo University of Science | Aoki S.,TokyoUniversity of Science
European Journal of Inorganic Chemistry | Year: 2011

A series of tris-cyclometalated IrIII complexes were prepared by regioselective substitution reactions (formylation, thiocyanation, and iodination) and subsequent conversions (cyanation, cross-coupling reaction, reduction, and oxidation) on a 2-(4′-methoxyphenyl)pyridine (mppy) ligand of fac-[Ir(mppy)3]. The introduction of electron-withdrawing groups such as CHO, CN, and sulfonyl groups (SO2Me, SO2Ar) at the 5′-position of the phenyl ring of the mppy portion induces a considerable blueshift in luminescence emission (from 495 nm to approximately 465 nm) in degassed organic solvents. © 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Kosaka Y.,University of Hawaii at Manoa | Xie S.-P.,University of Hawaii at Manoa | Nakamura H.,Tokyo University of Science | Nakamura H.,Japan Agency for Marine - Earth Science and Technology
Journal of Climate | Year: 2011

The summertime mei-yu-baiu rainband over East Asia displays considerable interannual variability. A singular value decomposition (SVD) analysis for interannual variability reveals that precipitation anomalies over the mei-yu-baiu region are accompanied by in situ anomalies of midtropospheric horizontal temperature advection. Anomalous warm (cool) advection causes increased (decreased) mei-yu-baiu precipitation locally by inducing adiabatic ascent (descent). The anomalous precipitation acts to reinforce the vertical motion, forming a feedback system. By this mechanism, the remotely forced anomalous atmospheric circulation can induce changes in mei-yu-baiu precipitation. The quasi-stationary precipitation anomalies induced by this mechanism are partially offset by transient eddies. The SVD analysis also reveals the association of mei-yu-baiu precipitation anomalies with several teleconnection patterns, suggesting remote induction mechanisms. The Pacific-Japan (PJ) teleconnection pattern, which is associated with anomalous convection over the tropical western North Pacific, contributes to mei-yu-baiu precipitation variability throughout the boreal summer. The PJ pattern mediates influences of the El Niño-Southern Oscillation in preceding boreal winter on mei-yu-baiu precipitation. In early summer, the leading covariability pattern between precipitation and temperature advection also features the Silk Road pattern-a wave train along the summertime Asian jet-and another wave train pattern to the north along the polar-front jet that often leads to the development of the surface Okhotsk high. © 2011 American Meteorological Society.

Kato S.,Japan Science and Technology Agency | Hashimoto K.,Japan Science and Technology Agency | Hashimoto K.,University of Tokyo | Hashimoto K.,Tokyo University of Science | And 3 more authors.
Environmental Microbiology | Year: 2012

Methanogenesis is an essential part of the global carbon cycle and a key bioprocess for sustainable energy. Methanogenesis from organic matter is accomplished by syntrophic interactions among different species of microbes, in which interspecies electron transfer (IET) via diffusive carriers (e.g. hydrogen and formate) is known to be the bottleneck step. We report herein that the supplementation of soil microbes with (semi)conductive iron-oxide minerals creates unique interspecies interactions and facilitates methanogenesis. Methanogenic microbes were enriched from rice paddy field soil with either acetate or ethanol as a substrate in the absence or presence of (semi)conductive iron oxides (haematite or magnetite). We found that the supplementation with either of these iron oxides resulted in the acceleration of methanogenesis in terms of lag time and production rate, while the supplementation with an insulative iron oxide (ferrihydrite) did not. Clone-library analyses of 16S rRNA gene fragments PCR-amplified from the enrichment cultures revealed that the iron-oxide supplementation stimulated the growth of Geobacter spp. Furthermore, the addition of a specific inhibitor for methanogenesis suppressed the growth of Geobacter spp. These results suggest that Geobacter grew under syntrophic association with methanogens, and IET could occur via electric currents through (semi)conductive iron-oxide minerals (termed 'electric syntrophy'). Given the ubiquity of conductive minerals in nature, such energetic interactions may occur widely in soil and sediments and can be used to develop efficient bioenergy processes. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Mori S.,Tokyo University of Science | Mori S.,Japan Research Institute of Innovative Technology for the Earth
Environmental Economics and Policy Studies | Year: 2014

It is already 4 years since the Intergovernmental Panel on Climate Change Special Report on Emission Scenarios (IPCC-SRES) and the IPCC Third Assessment Report (IPCC-TAR) activities indicated the various future emission pathways as well as the possible societal options. In the first decade of the 21st century, international negotiations on global warming mitigation have not progressed as well as expected. There are several possible reasons for this: (1) there are still many scientific uncertainties about climate change, especially regional change, and the warming may be beneficial to some and not to others; (2) there is insufficient knowledge on the impacts of climate change and the adaptation possibilities; and (3) there are difficulties about the assessments of the mitigation strategies in the long term and the spatial distribution. Although the activities of the IPCC have led to the compilation and proposal of extensive scientific findings, the gap between scientific findings and the political decisions remains deep. On the other hand, most nations agree with the importance of energy and environmental conservation as one of the key factors in sustainability. In this context, research on the long-term assessment of global warming should provide the basis for decision making as the comprehensive scientific information to support the dialogues among policy makers and stake holders. This article discusses two issues regarding scenario developments pending in the IPCC-SRES and IPCC-TAR activities: the role of narrative scenarios for the assessment of societal and economic structures, with introduction to our recent research activities and the effects of long-term uncertainties on short-term decisions. © 2006, Springer Japan.

Chen D.H.,Tokyo University of Science | Yang L.,Shenyang University of Technology
Composite Structures | Year: 2011

In this report, elastic moduli of honeycomb consisting of asymmetrical hexagonal cells are studied by using a theoretical approach and the finite element method (FEM). Based on the change in the shape of the hexagonal cell, explicit equations describing the equivalent elastic moduli of honeycomb with cell wall parallel to the y-axis are proposed. In the analysis of honeycomb deformation, the shear deformation was considered in addition to bending deformation and tensile deformation. As a result, the equivalent elastic moduli could be calculated with extremely high precision. © 2010 Elsevier Ltd.

Yamashita H.,Mathematical Systems Inc. | Yabe H.,Tokyo University of Science
Mathematical Programming | Year: 2012

In this paper, we consider a primal-dual interior point method for solving nonlinear semidefinite programming problems. We propose primal-dual interior point methods based on the unscaled and scaled Newton methods, which correspond to the AHO, HRVW/KSH/M and NT search directions in linear SDP problems. We analyze local behavior of our proposed methods and show their local and superlinear convergence properties. © 2010 Springer and Mathematical Programming Society.

Yamashita H.,Mathematical Systems Inc. | Yabe H.,Tokyo University of Science | Harada K.,Mathematical Systems Inc.
Mathematical Programming | Year: 2012

This paper is concerned with a primal-dual interior point method for solving nonlinear semidefinite programming problems. The method consists of the outer iteration (SDPIP) that finds a KKT point and the inner iteration (SDPLS) that calculates an approximate barrier KKT point. Algorithm SDPLS uses a commutative class of Newton-like directions for the generation of line search directions. By combining the primal barrier penalty function and the primal-dual barrier function, a new primal-dual merit function is proposed. We prove the global convergence property of our method. Finally some numerical experiments are given. © 2011 Springer and Mathematical Optimization Society.

Kiefer C.,University of Cologne | Queisser F.,University of Cologne | Starobinsky A.A.,Tokyo University of Science
Classical and Quantum Gravity | Year: 2011

We address the issue why a cosmological constant (dark energy) possesses a small positive value instead of being zero. Motivated by the cosmic landscape picture, we mimic the dark energy by a scalar field with potential wells and show that other degrees of freedom interacting with it can localize this field by decoherence in one of the wells. Dark energy can then acquire a small positive value. We also show that the additional degrees of freedom enhance the tunneling rate between the wells. The consideration is performed in detail for the case of two wells and then extended to a large number of wells. © 2011 IOP Publishing Ltd.

Tsuji H.,Yakult Central Institute for Microbiological Research | Moriyama K.,Yakult Central Institute for Microbiological Research | Nomoto K.,Yakult Central Institute for Microbiological Research | Akaza H.,Tokyo University of Science
Applied and Environmental Microbiology | Year: 2012

An Escherichia coli library comprising 8,424 strains incorporating gene fragments of the equol-producing bacterium Slackia sp. strain NATTS was constructed and screened for E. coli strains having daidzein- and dihydrodaidzein (DHD)-metabolizing activity. We obtained 3 clones that functioned to convert daidzein to DHD and 2 clones that converted DHD to equol. We then sequenced the gene fragments inserted into plasmids contained by these 5 clones. All of the gene fragments were contiguous, encoding three open reading frames (ORF-1, -2, and -3). Analysis of E. coli strains containing an expression vector incorporating one of the orf-1, -2, or -3 genes revealed that (i) the protein encoded by orf-1 was involved in the conversion of cis/trans-tetrahydrodaidzein (cis/trans-THD) to equol, (ii) the protein encoded by orf-2 was involved in the conversion of DHD to cis/trans-THD, and (iii) the protein encoded by orf-3 was involved in the conversion of daidzein to DHD. ORF-1 had a primary amino acid structure similar to that of succinate dehydrogenase. ORF-2 was presumed to be an enzyme belonging to the short-chain dehydrogenase/reductase superfamily. ORF-3 was predicted to have 42% identity to the daidzein reductase of Lactococcus strain 20-92 and belonged to the NADH:flavin oxidoreductase family. These findings showed that the daidzein-to-equol conversion reaction in the Slackia sp. NATTS strain proceeds by the action of these three enzymes. © 2012, American Society for Microbiology.

Kashiwaya S.,Japan National Institute of Advanced Industrial Science and Technology | Kashiwaya H.,Japan National Institute of Advanced Industrial Science and Technology | Kambara H.,Shinshu University | Furuta T.,Tokyo University of Science | And 3 more authors.
Physical Review Letters | Year: 2011

Tunneling spectroscopy has been performed on Sr2RuO4 searching for the edge states peculiar to topological superconductivity. Conductance spectra exhibit broad humps with three types of peak shape: domelike peak, split peak, and two-step peak. By comparing the experiments with predictions for unconventional superconductivity, these varieties are shown to originate from multiband chiral p-wave symmetry with weak anisotropy of pair amplitude. The broad hump in the conductance spectrum is a direct manifestation of the edge state due to chiral p-wave superconductivity. © 2011 American Physical Society.

Kishi T.,Tokyo University of Science | Tanaka H.,Tokyo University of Science | Umeda Y.,Tokyo University of Science | Takyu O.,Shinshu University
Journal of Lightwave Technology | Year: 2014

The modulation speed of light-emitting diodes (LEDs) must be increased to improve the speed, increase the bandwidth, and miniaturize the hardware of visible light communication (VLC) systems. The LED modulation speed is limited by the remaining carriers that remain in the depletion capacitance. In this paper, we evaluate the increase in optical transmission rate for an LED driver for the first time by sweeping out the remaining carriers in a GaN-based LED for VLC system. The driver is fabricated using discrete GaAs FETs and passive elements on a board. An optical transmission experiment is performed. The experimental results demonstrate that the driver increases the maximum error-free bit rate for a NRZ PRBS signal from 69 to 95 Mb/s (38% increase). However, the additional current path for carrier sweep-out increases the power dissipation of the driver. To reduce the power dissipation, we employ a CMOS inverter, in which a PMOS FET sweeps out the carriers. The driver is fabricated using a 0.18-μm CMOS IC process and then implemented in a package. The experimental results demonstrate that this design increased the maximum error-free bit rate from 27.5 to 51.8 Mb/s (88% increase). The maximum bit rate for the packaged driver is 20% higher than that of the driver measured on the wafer. © 1983-2012 IEEE.

Dahajipour Heidarabadi M.,Tarbiat Modares University | Ghanati F.,Tarbiat Modares University | Fujiwara T.,Tokyo University of Science
Plant Physiology and Biochemistry | Year: 2011

Aluminum toxicity is the most important limiting factor for plant growth and development in acidic soils (pH < 5.5). Inhibition of root growth has been considered as a sensitive marker of aluminum toxicity and the best indicator of boron deficiency as well. On the other hand cell wall phenolics (lignin and phenolic acids) have important roles in the reduction of extensibility of cell wall under stress conditions. Therefore, the interaction between boron and aluminum on phenolic compounds and the activity of the enzymes involved in their biosynthesis were investigated in flax seedlings. The seedlings were grown in Hoagland's solution and were treated with 3 B levels (4.5, 45 and 450 μM of H 3BO 3 at deficient, normal, and excess conditions, respectively) and 3 Al levels (0, 50 and 100 μM of AlCl 3.6H 2O). The results showed that Al treatment did not affect B content of roots (B content of Al-treated and non-treated plants were identical), while B treatment, particularly in higher concentrations, decreased Al content of roots compared with the control plants. In addition, the highest B concentration prevented the inhibitory effect of Al on the root length of plants. High concentrations of B also resulted in the decrease of enzyme activities involved in phenolic compounds (i.e., phenylalanine ammonia-lyase, polyphenol oxidase and peroxidase), decrease of lignin content and wall-bound phenols under Al stress, thereby ameliorating Al toxicity. The results suggest that the requirement of flax plants for B under Al stress conditions is higher than that required for growth in normal conditions without Al. © 2011 Elsevier Masson SAS.

Kibler B.,Laboratory Interdisciplinaire Carnot de Bourgogne | Chabchoub A.,Tokyo University of Science | Gelash A.,Novosibirsk State University | Akhmediev N.,Australian National University | Zakharov V.E.,Arizona State University
Physical Review X | Year: 2015

Since the 1960s, the Benjamin-Feir (or modulation) instability (MI) has been considered as the selfmodulation of the continuous "envelope waves" with respect to small periodic perturbations that precedes the emergence of highly localized wave structures. Nowadays, the universal nature of MI is established through numerous observations in physics. However, even now, 50 years later, more practical but complex forms of this old physical phenomenon at the frontier of nonlinear wave theory have still not been revealed (i.e., when perturbations beyond simple harmonic are involved). Here, we report the evidence of the broadest class of creation and annihilation dynamics of MI, also called superregular breathers. Observations are done in two different branches of wave physics, namely, in optics and hydrodynamics. Based on the common framework of the nonlinear Schrödinger equation, this multidisciplinary approach proves universality and reversibility of nonlinear wave formations from localized perturbations for drastically different spatial and temporal scales.

Hirakawa A.,Nagoya University | Hamada C.,Tokyo University of Science | Matsui S.,The Institute of Statistical Mathematics of Tokyo
Statistics in Medicine | Year: 2013

We develop a novel dose-finding method for two-agent combination phase I trials on the basis of the shrunken predictive probability of toxicity. In this method, a shrinkage logistic regression model that allows distinct shrinkage multipliers for the coefficients of the main effects of two agents and their interaction on the probability of toxicity constructs the toxicity outcome. We also propose dose-escalation/de-escalation decision rules on the basis of the shrunken predictive probability of toxicity. Simulation studies under various patterns of monotonic dose-response relationships for combinations of two agents demonstrated that the proposed method performed no worse than the existing two dose-finding methods we selected.© 2013 John Wiley & Sons, Ltd.

Tokyo University of Science and Yamagata University | Date: 2012-09-05

Provided are an image synthesizing device and an image synthesizing method wherein a subject is less affected by beam absorption. A diffraction beam intensity and a front diffraction beam intensity actually detected are included in the influence of absorption on a subject (Sa). Yet, assuming that said beams have the attenuation rate which is caused by said beams being absorbed when passing through a subject, the angle of refraction _(0) of the beam when passing through the subject (Sa) is obtained using the diffraction beam intensity and the front diffraction beam intensity which are not affected by attenuation, and which are represented by the aforementioned attenuation rate, front diffraction beam intensity, and diffraction beam intensity; a synthesized image of the subject (Sa) is obtained by means of said angle of refraction _(0).

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