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Ibaraki, Japan

The National Institute of Advanced Industrial Science and Technology , or AIST, is a Japanese research facility headquartered in Tokyo, and most of the workforce is located in Tsukuba Science City, Ibaraki, and in several cities throughout Japan. The institute is managed to integrate scientific and engineering knowledge to address socio-economic needs. It became a newly designed legal body of independent administrative institution in 2001, remaining under the Ministry of Economy, Trade and Industry. Wikipedia.


Nakanishi M.,Japan National Institute of Advanced Industrial Science and Technology | Otsu M.,Tokyo Medical University
Current Gene Therapy | Year: 2012

Gene delivery/expression vectors have been used as fundamental technologies in gene therapy since the 1980s. These technologies are also being applied in regenerative medicine as tools to reprogram cell genomes to a pluripotent state and to other cell lineages. Rapid progress in these new research areas and expectations for their translation into clinical applications have facilitated the development of more sophisticated gene delivery/expression technologies. Since its isolation in 1953 in Japan, Sendai virus (SeV) has been widely used as a research tool in cell biology and in industry, but the application of SeV as a recombinant viral vector has been investigated only recently. Recombinant SeV vectors have various unique characteristics, such as low pathogenicity, powerful capacity for gene expression and a wide host range. In addition, the cytoplasmic gene expression mediated by this vector is advantageous for applications, in that chromosomal integration of exogenous genes can be undesirable. In this review, we introduce a brief historical background on the development of recombinant SeV vectors and describe their current applications in gene therapy. We also describe the application of SeV vectors in advanced nuclear reprogramming and introduce a defective and persistent SeV vector (SeVdp) optimized for such reprogramming. © 2012 Bentham Science Publishers.


Ri S.,Japan National Institute of Advanced Industrial Science and Technology | Muramatsu T.,Tohoku University
Applied Optics | Year: 2012

Recently, a rapid and accurate single-shot phase measurement technique called the sampling moiré method has been developed for small-displacement distribution measurements. In this study, the theoretical phase error of the sampling moiré method caused by linear intensity interpolation in the case of a mismatch between the sampling pitch and the original grating pitch is analyzed. The periodic phase error is proportional to the square of the spatial angular frequency of the moiré fringe. Moreover, an effective phase compensation methodology is developed to reduce the periodic phase error. Single-shot phase analysis can perform accurately even when the sampling pitch is not matched to the original grating pitch exactly. The primary simulation results demonstrate the effectiveness of the proposed phase compensation methodology. © 2012 Optical Society of America.


Ohkubo T.,Chiba University | Ohira A.,Japan National Institute of Advanced Industrial Science and Technology | Iwadate Y.,Chiba University
Journal of Physical Chemistry Letters | Year: 2012

An NMR method was applied for the deconvolution of specific water in sulfonated polyether sulfone membranes, where sulfonated polyethersulfone is a proton-conducting polymer in polymer electrolyte membrane fuel cells. The distribution of 1H longitudinal relaxation times obtained by the inverse Laplace method was utilized to estimate the volume fraction of proton species as a function of relative humidity (RH). The relaxation time distribution clearly revealed two distinguished peaks on the order of 10 -3 and 10 -2 s, which corresponded to water in the larger and smaller channels for proton transports, respectively. We applied a pulse sequence to understand the water species by diffusion-weighted inversion recovery, which led to individual self-diffusion coefficients for deconvoluted water by using the longitudinal relaxation time. At 30% RH, the diffusion coefficient of water in small-sized channels is greater than that in large-sized channels. On the other hand, the diffusion coefficients of protons with smaller and larger water channels are almost the same at 50, 70, and 90% RH. © 2012 American Chemical Society.


Kobayashi T.,Japan National Institute of Advanced Industrial Science and Technology
Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition | Year: 2015

In contrast to category-level or cluster-level classifiers, exemplar SVM [17] is successfully applied to classifying (or detecting) a target object as well as transferring instance-level annotations. The method, however, is formulated in a highly biased classification problem where only one positive sample is contrasted with a substantial number of negative samples, which makes it difficult to properly determine the regularization parameters balancing two types of costs derived from positive and negative samples. In this paper, we present two novel viewpoints toward exemplar SVM in addition to the original definition. From these proposed viewpoints, we can give light on an intrinsic structure of exemplar SVM, reducing two parameters into only one as well as providing clear intuition on the parameter, in order to free us from exhaustive parameter tuning. We can also clarify how the classifier geometrically works so as to produce homogeneous classification scores of multiple exemplar SVMs which are comparable to each other without calibration. In addition, we propose a novel feature transformation method based on those viewpoints which contributes to general classification tasks. In the experiments on object detection and image classification, the proposed methods regarding exemplar SVM exhibit favorable performance. © 2015 IEEE.


Wang X.-F.,Yamagata University | Kitao O.,Japan National Institute of Advanced Industrial Science and Technology
Molecules | Year: 2012

Natural-chlorophyll-related porphyrins, including (2H, Zn, Cu)-protoporphyrin IX (Por-1) and Zn-mesoporphyrin IX (Por-2), and chlorins, including chlorin e 6 (Chl-1), chlorin e 4 (Chl-2), and rhodin G 7 (Chl-3), have been used in dye-sensitized solar cells (DSSCs). For porphyrin sensitizers that have vinyl groups at the β-positions, zinc coordinated Por-1 gives the highest solar-energy-to- electricity conversion efficiency (ν) of up to 2.9%. Replacing the vinyl groups of ZnPor-1 with ethyl groups increases the open-circuit voltage (V oc) from 0.61 V to 0.66 V, but decreases the short-circuit current (J sc) from 7.0 mA·cm-2 to 6.1 mA·cm-2 and the value of ν to 2.8%. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations suggest that the higher J sc values of Zn-based porphyrin sensitizers result from the favorable electron injection from the LUMO at higher energy levels. In the case of the chlorin sensitizers, the number of carboxyl protons has a large effect on the photovoltaic performance. Chl-2 with two carboxyl protons gives much higher values of J sc, V oc, and ν than does Chl-1 with three carboxyl protons. Replacing the protons of Chl-1 with sodium ions can substantially improve the photovoltaic performance of Chl-1-based solar cells. Furthermore, the sodium salt of Chl-3 with an aldehyde group at the C7 position shows poorer photovoltaic performance than does the sodium salt of Chl-1 with methyl groups at the C7 position. This is due to the low light-harvesting capability of Chl-3. © 2012 by the authors.


Ito F.,Japan National Institute of Advanced Industrial Science and Technology
Vibrational Spectroscopy | Year: 2014

Stable isomers of trifluoroacetic acid (TFA) pentahydrate clusters, TFA-(H2O)5, have been explored by using density functional theory calculations. As done for TFA-(H2O)4 (Ito, 2013), structure optimization and vibrational calculations were performed for 70 isomeric structures (68 for neutral and 2 for ion-pair species, respectively) at the B971/6-311++G(3df,3pd) level. We found that the edge-sharing bicyclic isomer is at the global minimum and that three other isomers lie energetically within 100 cm-1. Two types of ion-pair species were found to be unstable by 1100 cm-1 in comparison with the global minimum. The results were compared with infrared spectra observed in nitrogen matrix. © 2014 Elsevier B.V.


Nagaosa R.S.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Hazardous Materials | Year: 2014

This study proposes a new numerical formulation of the spread of a flammable gas leakage. A new numerical approach has been applied to establish fundamental data for a hazard assessment of flammable gas spread in an enclosed residential space. The approach employs an extended version of a two-compartment concept, and determines the leakage concentration of gas using a mass-balance based formulation. The study also introduces a computational fluid dynamics (CFD) technique for calculating three-dimensional details of the gas spread by resolving all the essential scales of fluid motions without a turbulent model. The present numerical technique promises numerical solutions with fewer uncertainties produced by the model equations while maintaining high accuracy. The study examines the effect of gas density on the concentration profiles of flammable gas spread. It also discusses the effect of gas leakage rate on gas concentration profiles. © 2014 The Authors.


Yabuki S.,Japan National Institute of Advanced Industrial Science and Technology
Analytical Sciences | Year: 2014

Long-term stability is a key property of enzyme membranes that can be used for biosensors, bioreactors, and bio-fuel cells. This review discusses factors that decrease the stability, and provides two examples of enzyme membranes, a polyion complex membrane and a cellulose membrane, with which stability loss can be avoided. By using these materials, long-term stability was improved. These supporting materials could be applied to construct biosensors, bioreactors, and bio-fuel cells. © 2014 The Japan Society For Analytical Chemistry.


Ogawa H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Alloys and Compounds | Year: 2013

Effects of lattice defects in vanadium hydrides on hydrogen storage property were analyzed by computer simulation. Element substitution, dislocation, and polyhedral surface were modeled as for point, line and plane lattice defects. DFT calculation revealed that Mo-substitution in β-phase vanadium hydride enhanced the shift of hydrogen occupancy from OZ1 site to neighboring T sites. Classical MD calculation on edge dislocation in a-phase vanadium hydride showed that interaction between edge dislocations was reduced by hydrogen aggregation at the vicinity of dislocation core. The MD simulation on polyhedral vanadium nanoparticle showed that polycrystal structure with fivefold symmetry can be generated by hydrogenation as a result of multi-twin-boundaries associated with bcc to bct transformation. Structure models of lattice defects were also briefly discussed. © 2013 Elsevier B.V. All rights reserved.


Nitta T.,Japan National Institute of Advanced Industrial Science and Technology
Neural Networks | Year: 2013

Most of local minima caused by the hierarchical structure can be resolved by extending the real-valued neural network to complex numbers. It was proved in 2000 that a critical point of the real-valued neural network with H - 1 hidden neurons always gives many critical points of the real-valued neural network with H hidden neurons. These critical points consist of many lines in the parameter space which could be local minima or saddle points. Local minima cause plateaus which have a strong negative influence on learning. However, most of the critical points of complex-valued neural network are saddle points unlike those of the real-valued neural network. This is a prominent property of the complex-valued neural network. © 2013 Elsevier Ltd.


Nakamura T.,Japan National Institute of Advanced Industrial Science and Technology
Diamond and Related Materials | Year: 2010

The photolysis of perfluoroazooctane in the presence of carbon materials, such as diamond powder, films, diamond-like carbon films, nanodiamond films and single-walled carbon nanotubes, led to the chemical modification of their surface by the introduction of perfluorooctyl functional groups, which was confirmed by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, time-of-flight secondary ionization mass spectrometry, Raman spectroscopy and mass spectroscopy measurements. The carbon materials modified with fluorine moieties exhibited a reduced friction coefficient and a reduction of their surface energy, evaluated by the contact angle with water, compared with those of pristine carbon materials. © 2009 Elsevier B.V. All rights reserved.


Hayashi H.,Japan National Institute of Advanced Industrial Science and Technology
Results in Physics | Year: 2012

Highly crystalline Eu 3+ doped yttria nanoparticle was synthesized by hydrothermal reaction in supercritical water using a continuous flow reaction system (FHT). The reactants of Y(NO 3) 3/Eu(NO 3) 3 mixed solution and KOH solution were used as starting materials and that was heated quickly up to 350-450°C under the pressure of 30MPa for 0.1-15s as reaction time. The XRD results revealed that the crystal phase of as-prepared particles was YOOH and converted into cubic-phase Y 2O 3 after annealing above 550°C. Primarily particle size of the YOOH was as small as less than 50nm, keeping after annealing at 800°C. Effects of reaction time, annealing temperature and Eu doping amount on photoluminescence were examined. The as-prepared particles exhibited red emission without annealing at high temperatures whereas photoluminescent intensity at 612nm was increased with an increase in the annealing temperature. Photoluminescent intensity was increased with an increase in the Eu doping amount until 4mol% and saturated at 8mol%. The photoluminescent property was compared with reference samples via conventional co-precipitation (CP) and batchwise hydrothermal (BHT) methods. The photoluminescent intensity for annealed samples increased in the order: FHT


Ishida N.,University of Leeds | Ishida N.,Japan National Institute of Advanced Industrial Science and Technology | Biggs S.,University of Leeds
Macromolecules | Year: 2010

The effect of grafting density on the phase transition behavior of poly(N-isopropylacrylamide) (PNIPAM) grafted onto a flat substrate was investigated using an atomic force microscope (AFM) and a quartz crystal microbalance (QCM-D). We prepared PNIPAM brush layers at three different grafting densities on silicon wafers using a "grafting from" atom transfer radical polymerization (ATRP) approach. AFM imaging in water at various temperatures showed that the transition behavior of the grafted PNIPAM chains from a brush-like to a mushroom-like morphology was dependent on the grafting density: the images change abruptly from essentially featureless to domain structures across the LCST for the low-density surface, whereas the change in the images becomes less abrupt with increasing polymer graft density. The QCM-D data also indicated a significant dependence of the layer properties on the grafting density, confirming the behavior differences suggested by the AFM images. In particular, the dissipation data strongly suggest that the magnitude of lateral aggregation for the PNIPAM chains depends on the grafting density. A similar effect of grafting density was also observed for the phase transition as a function of salt concentration in sodium sulfate solutions. © 2010 American Chemical Society.


Utsumi Y.,Mie University | Taniguchi T.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review Letters | Year: 2015

We consider a reversal of the magnetic moment of a nanomagnet by a fluctuating spin torque induced by a nonequilibrium current of electron spins. This is an example of the problem of the escape of a particle from a metastable state subjected to a fluctuating nonconservative force. Spin torque is a nonconservative force, and its fluctuations are beyond the description of the fluctuation-dissipation theorem. We estimate the joint probability distribution of work done by the spin torque and the Joule heat generated by the current, which satisfies the fluctuation theorem for a small engine. We predict a threshold voltage above which the spin-torque shot noise induces probabilistic switching events and below which such events are blocked. We adopt the theory of full-counting statistics under the adiabatic pumping of spin angular momentum. This enables us to account for the backaction effect, which is crucial to maintain consistency with the fluctuation theorem. © 2015 American Physical Society.


Ishibashi S.,Japan National Institute of Advanced Industrial Science and Technology
Journal of the Physical Society of Japan | Year: 2015

The positron-monovacancy interaction in d-block metals (except for Mn, Tc, and Hg) has been studied by the twocomponent density-functional-theory formalism [E. Boroński and R. M. Nieminen, Phys. Rev. B 34, 3820 (1986)]. On the unrelaxed structure, the positron lifetime calculated with the presence of a positron is generally longer than that obtained neglecting the positron effect. When the atomic positions are relaxed, the difference is widened, especially for the group V metals. The inward relaxation of the atoms surrounding the monovacancy is suppressed when the positron effect is taken into account. The difference in the positron lifetime can be also related to the bulk modulus and the cohesive energy. ©2015 The Physical Society of Japan.


Shimada S.,Japan National Institute of Advanced Industrial Science and Technology
Current Organic Chemistry | Year: 2011

This review overviews the advances in the chemistry of bismuth-containing heterocyclic compounds during the last decade. Some new types of bismuth-containing heterocyclic systems containing nitrogen, oxygen, sulfur and/or phosphorus in addition to bismuth have been synthesized. 5,6,7,12-Tetrahydrodibenz[c,f][1,5]azabismocine derivatives were the most extensively studied bismuthcontaining heterocyclic compounds during the last decade, and a number of new compounds were synthesized. Their application to organic synthesis has shown that they are useful as reagents for the cross-coupling reaction with organic halides and as Lewis acid catalysts. Also they were used for the fixation of CO 2. Some pentavalent bismuth-containing heterocyclic compounds were found to be useful in organic synthesis. Biological activity of some of bismuth-containing heterocyclic compounds was studied and found to show antimicrobial, antibacterial, antifungal, and anticancer activities. © 2011 Bentham Science Publishers Ltd.


Nomura N.,Japan National Institute of Advanced Industrial Science and Technology
Statistics and Computing | Year: 2016

In this paper, a new procedure is described for evaluating the probability that all elements of a normally distributed vector are non-negative, which is called the non-centered orthant probability. This probability is defined by a multivariate integral of the density function. The definition is simple, and this probability arises frequently in statistics because the normal distribution is prevalent. The method for evaluating this probability, however, is not obvious, because applying direct numerical integration is not practical except in low dimensional cases. In the procedure proposed in this paper, the problem is decomposed into sub-problems of lower dimension. Considering the projection onto subspaces, the solutions of the sub-problems can be shared in the evaluation of higher dimensional problems. Thus the sub-problems form a lattice structure. This reduces the computational time from a factorial order, where the interim results are not shared, to order (Formula presented.), which is faster than the procedures that have been reported in the literature. © 2014, Springer Science+Business Media New York.


Negishi H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of the European Ceramic Society | Year: 2016

Conventional organic solvents used for electrophoretic deposition (EPD) exhibit several advantages such as high electrical resistance, zero bubble formation, and the feasibility of using high voltages. However, they can be hazardous because of their high inflammability or low ignition temperatures. In this study, methoxy-nonafluorobutane (MNFB) was used as a solvent for the EPD of silica powder. MNFB is nonflammable, polar, and possesses excellent electrical insulation properties. The density of MNFB is greater than that of water, and therefore, the sedimentation of inorganic particles in MNFB is slow. As a result, a uniform coating was obtained. The deposition behavior in MNFB was similar to that observed during EPD in conventional solvents. Further, the deposition of silica could be controlled by deposition time using high voltages. The power consumed during the process was less than 0.1% of that used during EPD with conventional solvents. Therefore, MNFB is an effective solvent for EPD. © 2015 Elsevier Ltd.


Kimura T.,Japan National Institute of Advanced Industrial Science and Technology
Macromolecular Rapid Communications | Year: 2013

Exclusive organic templating of macroporous oxide films is reported by using non-close and lose packing of spherical copolymer aggregates, in combination with facile control of condensation degree/density of inorganic oxide frameworks. Unique macroporous oxide films, mainly titania showing highly porous, crystalline, and versatile properties, can be fabricated with continuous design from unusual 3-D net-shape to tunable spherical macrostructures, which expands the preparation of other inorganic oxide films (silica, alumina, and zirconia) and possibly adapts the use of other assembled organic polymers. The macroporous structures are helpful for effective accommodation of bulky biomoleculeshigh and diffusivity of organic molecules (useful for photocatalysts). Unusual structural variation, expansion of spherical voids, is also observed, being useful for fine tuning of optical property. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang H.,Sichuan University | Miyamoto Y.,Technology Research Association for Single Wall Carbon Nanotubes TASC | Miyamoto Y.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

By performing the first-principles simulation of electron-ion dynamics based on the time-dependent density-functional theory, we propose a way to produce graphene from graphene oxides by means of the laser-induced reduction without using chemical species. Epoxy and hydroxyl groups on graphene sheets can be completely removed upon irradiation with femtosecond laser without damaging the graphene sheet. By comparing the simulated results with different pulse shapes and intensities, optimum conditions of the femtosecond laser for reduction of graphene oxide were determined. The current works will be useful for further experimental researches. © 2012 American Physical Society.


Nuida K.,Japan National Institute of Advanced Industrial Science and Technology
International Journal of Information Security | Year: 2012

In this article, we propose a new construction of probabilistic collusion-secure fingerprint codes against up to three pirates and give a theoretical security evaluation. Our pirate tracing algorithm combines a scoring method analogous to Tardos codes (J ACM 55:1-24, 2008) with an extension of parent search techniques of some preceding 2-secure codes. Numerical examples show that our code lengths are significantly shorter than (about 30-40% of) the shortest known c-secure codes by Nuida et al. (Des Codes Cryptogr 52:339-362, 2009) with c = 3. © Springer-Verlag 2012.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2014

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since July 2013 are reviewed. Copyright © 2013 John Wiley & Sons, Ltd.


Maekawa T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Chemical and Engineering Data | Year: 2012

Equilibrium conditions of ethane hydrates in aqueous solutions of methanol, ethanol, ethylene glycol, diethylene glycol, triethylene glycol, and glycerol were experimentally measured at temperatures ranging from (261.6 to 285.9) K and pressures of up to 3.12 MPa using an isochoric method. On a mass fraction basis, the inhibiting effect on ethane hydrate formation decreased in the following order: methanol > ethanol > ethylene glycol > glycerol ≈ diethylene glycol > triethylene glycol. © 2012 American Chemical Society.


Tsugawa S.,Meijo University | Kato S.,Japan National Institute of Advanced Industrial Science and Technology
IEEE Communications Magazine | Year: 2010

Recent annual CO 2 emission from Japan sums up to 1.2 billion ton, and about 17 percent of it is from automobile traffic. There are many approaches to reduce CO 2 emission and to prevent the global warming, and one of the important approaches is the Intelligent Transport Systems. This article surveys the effects of the ITS on the energy saving and global warming prevention based on the data in Japan, focusing on the applications of vehicular communication technologies. The ITS could contribute to the energy saving on two aspects: one is to eliminate the congestion, which enables each automobile to drive at the fuel optimal speeds, and the other is to provide means for modal shift, which reduces the traffic. This article surveys the ITS technologies for energy saving and CO 2 emission reduction, which include traffic signal control, ETC, route guidance, cruise control, and automated driving. The road-to-vehicle and vehicleto- vehicle communications play an essential role in energy saving as well as in the safety of automobiles and road transportation. © 2006 IEEE.


Tanaka H.K.,University of Tokyo | Kusagaya T.,University of Tokyo | Shinohara H.,Japan National Institute of Advanced Industrial Science and Technology
Nature communications | Year: 2014

Radiographic imaging of magma dynamics in a volcanic conduit provides detailed information about ascent and descent of magma, the magma flow rate, the conduit diameter and inflation and deflation of magma due to volatile expansion and release. Here we report the first radiographic observation of the ascent and descent of magma along a conduit utilizing atmospheric (cosmic ray) muons (muography) with dynamic radiographic imaging. Time sequential radiographic images show that the top of the magma column ascends right beneath the crater floor through which the eruption column was observed. In addition to the visualization of this magma inflation, we report a sequence of images that show magma descending. We further propose that the monitoring of temporal variations in the gas volume fraction of magma as well as its position in a conduit can be used to support existing eruption prediction procedures.


Hurst J.W.,Oregon State University | Chestnutt J.E.,Japan National Institute of Advanced Industrial Science and Technology | Rizzi A.A.,Boston Dynamics
IEEE Transactions on Robotics | Year: 2010

Running is a complex dynamic task that places strict requirements on both the physical components and software-control systems of a robot. This paper explores some of those requirements and, in particular, explores how a variable-compliance actuation system can satisfy many of them. We present the mechanical design and software-control system for such an actuator system. We analyze its performance through simulation and bench-top experimental validation of a prototype version. In conclusion, we demonstrate, through simulation, the application of our proof-of-concept actuator to the problem of biped running. © 2010 IEEE.


Yamaguchi H.,Tokai University | Miyazaki M.,Japan National Institute of Advanced Industrial Science and Technology
Biomolecules | Year: 2014

Biologically active proteins are useful for studying the biological functions of genes and for the development of therapeutic drugs and biomaterials in a biotechnology industry. Overexpression of recombinant proteins in bacteria, such as Escherichia coli, often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. As inclusion bodies contain relatively pure and intact proteins, protein refolding is an important process to obtain active recombinant proteins from inclusion bodies. However, conventional refolding methods, such as dialysis and dilution, are time consuming and, often, recovered yields of active proteins are low, and a trial-and-error process is required to achieve success. Recently, several approaches have been reported to refold these aggregated proteins into an active form. The strategies largely aim at reducing protein aggregation during the refolding procedure. This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.


Nakaoka S.,Japan National Institute of Advanced Industrial Science and Technology
2012 IEEE/SICE International Symposium on System Integration, SII 2012 | Year: 2012

Virtual robot models are often used for developing, testing, and using robot systems. Such activities can be efficiently conducted by using software tools for visualizing and operating virtual robots with a graphical user interface (GUI). However, existing GUI tools such as robot simulators do not provide all the functions necessary for handling a target robot system, and the development of new GUI tools from the ground up to actuate functions requires considerable effort. To solve this problem, we have developed a software framework called Choreonoid, which allows users to efficiently implement and integrate various GUI tools for handling virtual robots. In this paper, we present the framework design. The validity of our design and implementation is shown by example tools implemented on the Choreonoid framework. © 2012 IEEE.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2014

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January 2014 are reviewed. Copyright © 2014 John Wiley & Sons, Ltd.


The self-diffusion coefficients, D, of lithium, anions, and solvents in four binary-solution electrolytes of ethylene carbonate (EC)-diethyl carbonate (DEC) and three single-solution electrolytes of EC, DEC, and propylene carbonate (PC) including 1 M LiPF 6 were measured by 1H, 7Li, and 19F NMR spectroscopy from (353 to 243) K or above freezing for seven solution electrolytes. In the single DEC electrolyte, D Li and D PF6 had almost the same values at every temperature, whereas D Li was smaller than D PF6 in the EC and PC solutions. In the binary EC-DEC electrolytes, as the ratio of EC increased, D Li gradually became smaller, while D PF6 remained almost unchanged in the temperature range studied. At 303 K, the degree of ion dissociation α was evaluated from the ionic conductivity, D Li and D PF6. The α value increased from 0.17 to 0.71 as the EC ratio increased from (0 to 100) %. © 2012 American Chemical Society.


Funahashi M.,Kagawa University | Sonoda A.,Japan National Institute of Advanced Industrial Science and Technology
Dalton Transactions | Year: 2013

A liquid-crystalline (LC) perylene tetracarboxylic bisimide (PTCBI) derivative bearing a triethylene oxide chain as well as two pentamethyldisiloxane chains was synthesized. This compound exhibits an ordered lamellar phase at room temperature, and the LC phase is retained when the sample is cooled to -100 °C. Due to the presence of extended π-conjugated perylene rings, efficient electron transport occurs in the lamellar phase and the electron mobility exceeds 1 × 10-3 cm2 V -1 s-1 at room temperature. Moreover, this PTCBI derivative can form a complex with lithium triflate because of the polar triethylene oxide chain. Lithium triflate can be mixed with it up to 3 mol%. Up to this concentration, the lamellar LC structure and the electron transport properties are not perturbed by the presence of the ionic species. © 2013 The Royal Society of Chemistry.


Okubo M.,Japan National Institute of Advanced Industrial Science and Technology | Honma I.,Tohoku University
Dalton Transactions | Year: 2013

Ternary metal Prussian blue analogue nanoparticles were applied as cathode materials for Li-ion batteries. Heterometal substitution suppressed phase separation induced by over-lithiation, leading to both a long cycle life and a high rate capability. © 2013 The Royal Society of Chemistry.


Nagaosa R.S.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Computational Physics | Year: 2014

This paper proposes a new numerical modelling to examine environmental chemodynamics of a gaseous material exchanged between the air and turbulent water phases across a gas-liquid interface, followed by an aquarium chemical reaction. This study uses an extended concept of a two-compartment model, and assumes two physicochemical substeps to approximate the gas exchange processes. The first substep is the gas-liquid equilibrium between the air and water phases, A(g)⇌A(aq), with Henry's law constant H. The second is a first-order irreversible chemical reaction in turbulent water, A(aq)+H2O→B(aq)+H+ with a chemical reaction rate κA. A direct numerical simulation (DNS) technique has been employed to obtain details of the gas exchange mechanisms and the chemical reaction in the water compartment, while zero velocity and uniform concentration of A is considered in the air compartment. The study uses the different Schmidt numbers between 1 and 8, and six nondimensional chemical reaction rates between 10-∞(≈0) to 101 at a fixed Reynolds number. It focuses on the effects of the Schmidt number and the chemical reaction rate on fundamental mechanisms of the gas exchange processes across the interface. © 2013 The Author.


Nagao J.,Japan National Institute of Advanced Industrial Science and Technology
Synthesiology | Year: 2012

Natural gas hydrates off the shores of Japan are valuable resources for the country. To utilize these resources, it is necessary to establish a gas production technology and investigate suitable conditions for extraction of methane from methane hydrate reservoirs. While core-scale dissociation experiments yield reproducible results on how methane hydrate dissociates under various conditions, a production test at a real gas field would provide information about the type of dissociation phenomena occurring in a geological reservoir field. The performance of natural gas production from methane hydrate reservoirs is dependent upon the size and characteristics of reservoirs, such as temperature and permeability. In other words, while a core-scale dissociation test in a laboratory can demonstrate the heat transport process, dissociation in an actual reservoir is dominated by the material flow process. Thus, I believe that it is important to couple data obtained from core-scale tests with the results of field-scale tests by using a large-scale laboratory reactor in which dissociation experiments can be conducted under similar conditions to the actual reservoir. In this paper, I report the goals of the Methane Hydrate Research and Development Program being conducted by the Ministry of Economy, Trade and Industry, Japan, and describe the research objective of a large-scale laboratory reactor for methane hydrate production tests at MHRC (Methane Hydrate Research Center) of AIST (National Institute of Advanced Industrial Science and Technology).


Niki E.,Japan National Institute of Advanced Industrial Science and Technology
Current Pharmaceutical Biotechnology | Year: 2010

It is now widely accepted that oxidative stress induced by reactive oxygen and nitrogen species is involved in the pathogenesis of various diseases such as atherosclerosis and cardiovascular disease and consequently the role of antioxidants in the prevention and treatment of diseases has received much attention of scientists, clinicians and general public. However, most of the large clinical intervention trials of antioxidants and meta-analysis of the data from these large studies do not show beneficial evidence with regard to cardiovascular outcomes. In order to understand the role of antioxidants, it is essential to elucidate the action and capacity of antioxidants. In this article, the assessment of antioxidant capacity is reviewed and the methods for assessment of natural antioxidant capacity are discussed. © 2010 Bentham Science Publishers Ltd.


Matsumoto M.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Cleaner Production | Year: 2010

To discuss measures to promote reuse in society, a holistic understanding of reuse businesses and markets is indispensable. This paper presents a simulation model for reuse businesses. To formulate the model, first, prerequisites for reuse businesses are outlined. The simulation model includes these prerequisites as its parameters, and its outcomes yield patterns of reuse markets. The paper presents the formulation of the model and simulation outcomes under four parameter settings. The correspondences between the simulation outcomes and case studies of reuse businesses in Japan are discussed to verify the propriety of the model. © 2010 Elsevier Ltd. All rights reserved.


Endo S.,Japan National Institute of Advanced Industrial Science and Technology | Tsuboi M.,Kwansei Gakuin University
Journal of Metamorphic Geology | Year: 2013

Jadeite-bearing kyanite eclogite has been discovered in the Iratsu body of the Sanbagawa belt, SW Japan. The jadeite + kyanite assemblage is stable at higher pressure-temperature (P-T) conditions or lower H2O activity [a(H2O)] than paragonite, although paragonite-bearing eclogite is common in the Sanbagawa belt. The newly discovered eclogite is a massive metagabbro with the peak-P assemblage garnet + omphacite + jadeite + kyanite + phengite + quartz + rutile. Impure jadeite is exclusively present as inclusions in garnet. The compositional gap between the coexisting omphacite (P2/n) and impure jadeite (C2/c) suggests relatively low metamorphic temperatures of 510-620 °C. Multi-equilibrium thermobarometry for the assemblage garnet + omphacite + kyanite + phengite + quartz gives peak-P conditions of ~2.5 GPa, 570 °C. Crystallization of jadeite in the metagabbro is attributed to Na- and Al-rich effective bulk composition due to the persistence of relict Ca-rich clinopyroxene at the peak-P stage. By subtracting relict clinopyroxene from the whole-rock composition, pseudosection modelling satisfactorily reproduces the observed jadeite-bearing assemblage and mineral compositions at ~2.4-2.5 GPa, 570-610 °C and a(H2O) >0.6. The relatively high pressure conditions derived from the jadeite-bearing kyanite eclogite are further supported by high residual pressures of quartz inclusions in garnet. The maximum depth of exhumation in the Sanbagawa belt (~80 km) suggests decoupling of the slab-mantle wedge interface at this depth. © 2013 John Wiley & Sons Ltd.


Fu S.-C.,National Taiwan University | Huang H.-C.,National Yang Ming University | Horton P.,Japan National Institute of Advanced Industrial Science and Technology | Juan H.-F.,National Taiwan University
Nucleic Acids Research | Year: 2013

ValidNESs (http://validness.ym.edu.tw/) is a new database for experimentally validated leucine-rich nuclear export signal (NES)-containing proteins. The therapeutic potential of the chromosomal region maintenance 1 (CRM1)-mediated nuclear export pathway and disease relevance of its cargo proteins has gained recognition in recent years. Unfortunately, only about one-third of known CRM1 cargo proteins are accessible in a single database since the last compilation in 2003. CRM1 cargo proteins are often recognized by a classical NES (leucine-rich NES), but this signal is notoriously difficult to predict from sequence alone. Fortunately, a recently developed prediction method, NESsential, is able to identify good candidates in some cases, enabling valuable hints to be gained by in silico prediction, but until now it has not been available through a web interface. We present ValidNESs, an integrated, up-to-date database holding 221 NES-containing proteins, combined with a web interface to prediction by NESsential. © The Author(s) 2012.


Tomita K.,Japan National Institute of Advanced Industrial Science and Technology
International Journal of Molecular Sciences | Year: 2014

Qβ replicase is a unique RNA polymerase complex, comprising Qβ virus-encoded RNA-dependent RNA polymerase (the catalytic β-subunit) and three host-derived factors: translational elongation factor (EF) -Tu, EF-Ts and ribosomal protein S1. For almost fifty years, since the isolation of Qβ replicase, there have been several unsolved, important questions about the mechanism of RNA polymerization by Qβ replicase. Especially, the detailed functions of the host factors, EF-Tu, EF-Ts, and S1, in Qβ replicase, which are all essential in the Escherichia coli (E. coli) host for protein synthesis, had remained enigmatic, due to the absence of structural information about Qβ replicase. In the last five years, the crystal structures of the core Qβ replicase, consisting of the β-subunit, EF-Tu and Ts, and those of the core Qβ replicase representing RNA polymerization, have been reported. Recently, the structure of Qβ replicase comprising the β-subunit, EF-Tu, EF-Ts and the N-terminal half of S1, which is capable of initiating Qβ RNA replication, has also been reported. In this review, based on the structures of Qβ replicase, we describe our current understanding of the alternative functions of the host translational elongation factors and ribosomal protein S1 in Qβ replicase as replication factors, beyond their established functions in protein synthesis. © 2014 by the authors; licensee MDPI, Basel, Switzerland.


Hagihara Y.,Japan National Institute of Advanced Industrial Science and Technology | Saerens D.,Vrije Universiteit Brussel
Biochimica et Biophysica Acta - Proteins and Proteomics | Year: 2014

Antibodies have evolved to function in oxidative, extracellular environments. A pair of cysteines in close proximity will oxidatively react to form a disulfide bond that fixes and stabilizes the tertiary structure of a protein. Immunoglobulin G (IgG) includes several disulfide bonds, and the patterns of inter-chain disulfide bonds characterize different IgG sub-classes. Moreover, the Ig-fold domains are characterized by a buried intra-domain disulfide bond, which is important for its structural stability. However, the intra-domain disulfide bond can be replaced without crucial effects on the structure and function, if the domain structure is intrinsically stable or has been stabilized by protein engineering. In previous studies, disulfide bonds were removed by amino-acid substitution indicating that Val and/or Ala (i.e. Ala-Ala, Ala-Val, Val-Ala, and Val-Ala) pairs were preferred for cysteine replacement in the Ig-fold domain. As such, these mutations may be useful for the intracellular use of antibodies. Recently, additional intra-domain disulfide bonds have been shown to stabilize Ig-fold domains and whole IgGs. In heavy chain variable or light chain variable domains, the introduction of additional disulfide bonds into the framework region did not reduce antigen-binding affinity, suggesting that generating disulfide bonds may be a method for stabilizing IgG and antibody fragments, such as the antigen-binding fragment, and single-chain and single-domain antibodies. This article is part of a Special Issue entitled: Recent advances in molecular engineering of antibody. © 2014 Elsevier B.V.


Singh S.K.,Indian Institute of Technology Indore | Xu Q.,Japan National Institute of Advanced Industrial Science and Technology
Catalysis Science and Technology | Year: 2013

Hydrogen is an key future fuel of interest because it is considered as an efficient energy carrier, like electricity, releasing only water when combining with oxygen (e.g. in a fuel cell) and therefore has no negative impact on the environment. Unfortunately we are not yet able to clear the economical and engineering hurdles to store hydrogen safely and efficiently. To overcome this, onboard hydrogen generation by hydrogen storage materials comes out to be an attractive and effective approach. Therefore, the concept of onboard hydrogen generation and use based on our requirements are gaining interest, reflected by a huge number of hydrogen storage materials with high hydrogen contents. Among them, hydrous hydrazine, which is a liquid and has a hydrogen content for hydrogen release as high as 8.0 wt%, proves to be a strong candidate for onboard hydrogen generation at ambient conditions. Nanoparticle catalysts (nanocatalysts) play a significant role to control the selective generation of hydrogen from catalytic decomposition of hydrous hydrazine. Nanocatalysts based on monometallic or two-component alloy catalysts involving noble (Ru, Rh, Pt, Pd, Ir) and non-noble metals (Fe, Co, Ni, Cu) and various non-metals have been extensively studied. Screening of a vast range of nanocatalysts thus provides a library of active and selective catalysts. The structure and activity of nanocatalysts are discussed focusing on the structure-activity relationship for selective hydrogen generation from hydrous hydrazine. This journal is © 2013 The Royal Society of Chemistry.


Tuziuti T.,Japan National Institute of Advanced Industrial Science and Technology
Ultrasonics Sonochemistry | Year: 2016

This paper describes the sizes of cleaned areas under different sonication conditions with the addition of flowing micrometer-sized air bubbles. The differences in the cleaned area of a glass plate pasted with silicon grease as a dirty material under different sonication conditions were investigated after tiny bubbles were blown on the dirty plate placed in an underwater sound field. The ultrasound was applied perpendicular to the bubble flow direction. The shape of the cleaned areas was nearly elliptical, so the lengths of the minor and major axes were measured. The length of the minor axis under sweep conditions (amplitude modulation), for which the average power was lower than that for continuous wave (CW) irradiation, was comparable to that for CW irradiation and was slightly larger than under bubble flow only. Not only the relatively high power for CW irradiation, but also the larger angular change of the bubble flow direction under sweep conditions contributed to the enlargement of the cleaned area in the direction of the minor axis. The combination of bubble flow and sonication under sweep or CW conditions produced a larger cleaned area compared with bubble flow only, although the increase was not higher than 20%. A rapid change from an air to water interface caused by the bubble flow and water jets caused by the collapse of bubbles due to violent pulsation is the main cleaning mechanism under a combination of ultrasound and bubble flow. © 2015 Elsevier B.V.


Hibino T.,Japan National Institute of Advanced Industrial Science and Technology
Applied Clay Science | Year: 2011

Methods for preparation of nanoplates of layered double hydroxides (LDHs) have been intensively investigated for the purpose of making nanocomposites. The present study provides a new simple method of nanoplate preparation for Zn-Al LDHs. Zn-Al LDHs containing lactate or combinations of lactate and simple inorganic anions were synthesized by a coprecipitation method, and water-washed and undried LDHs were dispersed in water. Among them, suspensions of Zn-Al LDHs containing both lactate and bicarbonate were unique in that they rapidly became translucent colloidal dispersions when the molar ratio of added bicarbonate to added Al was ≤ 0.5. The resulting LDH nanoplates in the dispersions were delaminated single layers or nanoplates with a thickness of several layers, depending on the amount of bicarbonate. © 2011 Elsevier B.V.


Watanabe S.,University of Tokyo | Minami N.,Japan National Institute of Advanced Industrial Science and Technology | Shimano R.,University of Tokyo
Optics Express | Year: 2011

We have investigated the highly nonlinear terahertz (THz) light-matter interaction in single-walled carbon nanotubes (SWNTs). The high-peak THz electric-field (∼0.7 MV/cm) and the low effective mass of carriers result in their ponderomotive energy exceeding the bandgap energy of semiconducting SWNTs. Under such an intense THz pulse irradiation, the interband excitation that results in the generation of excitons occurs, although the THz photon energy (∼4 meV) is much smaller than the gap energy of SWNTs (∼1 eV). The ultrafast dynamics of this exciton generation process is investigated by THz pump and optical probe spectroscopy. The exciton generation mechanism is described by impact excitation process induced by the strong THz E-field. Such intense THz pulse excitation provides a powerful tool to study nonlinear terahertz optics in non-perturbative regime as well as nonlinear transport phenomena in solids with ultrafast temporal resolution. © 2011 Optical Society of America.


Makino K.,University of Tsukuba | Tominaga J.,Japan National Institute of Advanced Industrial Science and Technology | Hase M.,University of Tsukuba
Optics Express | Year: 2011

A class of chalcogenide alloy materials that shows significant changes in optical properties upon an amorphous-to-crystalline phase transition has lead to development of large data capacities in modern optical data storage. Among chalcogenide phase-change materials, Ge2Sb2Te5 (GST) is most widely used because of its reliability. We use a pair of femtosecond light pulses to demonstrate the ultrafast optical manipulation of atomic arrangements from tetrahedral (amorphous) to octahedral (crystalline) Ge-coordination in GST superlattices. Depending on the parameters of the second pump-pulse, ultrafast nonthermal phase-change occurred within only few-cycles (≈1 picosecond) of the coherent motion corresponding to a GeTe4 local vibration. Using the ultrafast switch in chalcogenide alloy memory could lead to a major paradigm shift in memory devices beyond the current generation of silicon-based flash-memory. © 2011 Optical Society of America.


Tani H.,Japan National Institute of Advanced Industrial Science and Technology | Akimitsu N.,University of Tokyo
RNA Biology | Year: 2012

Changing the abundance of transcripts by regulated RNA degradation is a critical step in the control of various biological pathways. Recently, genome-wide inhibitor-free technologies for determining RNA stabilities in mammalian cells have been developed. In these methods, endogenous RNAs are pulse labeled by uridine analogs [e.g., 4-thiouridine (4sU), 5-etyniluridine (EU) and 5'-bromo-uridine (BrU)], followed by purification of labeled de novo RNAs. These technologies have revealed that the specific half-life of each mRNA is closely related to its physiological function. Genes with short-lived mRNAs are significantly enriched among regulatory genes, while genes with long-lived mRNAs are enriched among housekeeping genes. This review describes the recent progress of experimental procedures for measuring RNA stability. © 2012 Landes Bioscience.


Wang T.,National University of Singapore | Kobayashi T.,Japan National Institute of Advanced Industrial Science and Technology | Lee C.,National University of Singapore
Applied Physics Letters | Year: 2015

An ultrasonic transducer with a wide frequency bandwidth is always preferred for diagnostic ultrasound imaging, because a wide frequency bandwidth can reduce the duration of an ultrasonic pulse and enhance the axial imaging resolution. However, the frequency bandwidth of both conventional ultrasonic transducer and normal piezoelectric micromachined ultrasonic transducer (pMUT) is quite limited. To overcome this limitation, the mode-merging pMUT is presented in this letter. By using the rectangular membrane with large length/width aspect ratio, several resonant modes are excited within a narrow frequency range. When this pMUT works in a largely damped medium, excited modes are merged together and result in an ultra-wide bandwidth. A -6 dB bandwidth of 95% is measured in water for the proposed pMUT without matching layer, which is much broader than that of conventional pMUTs. Benefited from such ultra-wide frequency bandwidth, the pulse duration of 1 μs is achieved at a central frequency of 1.24 MHz. If this ultra-wide bandwidth pMUT is utilized to replace the conventional transducer for diagnostic ultrasound imaging, the axial resolution can be significantly enhanced without compromising imaging depth. © 2015 AIP Publishing LLC.


Mizuno H.,Nara Institute of Science and Technology | Ohnishi I.,Nara Institute of Science and Technology | Yanagi H.,Nara Institute of Science and Technology | Sasaki F.,Japan National Institute of Advanced Industrial Science and Technology | Hotta S.,Kyoto Institute of Technology
Advanced Materials | Year: 2012

Optically pumped lasing of epitaxially oriented molecular crystals is presented. Needle-like crystals of a thiophene/phenylene co-oligomer is grown along the [110] direction of a KCl substrate. The fluorescence light is one-dimensionally confined and amplified by the self-waveguiding effect in the elongated needles. The Fabry-Pérot resonation by the terminated ends results in laser oscillations corresponding to the needle length. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ishizaki T.,Japan National Institute of Advanced Industrial Science and Technology | Saito N.,EcoTopia Science Institute | Takai O.,Nagoya University
Langmuir | Year: 2010

A micropatterned superhydrophobic/superhydrophilic surface was successfully fabricated by plasma CVD and VUV irradiation. Physicochemical properties of the superhydrophobic, superhydrophilic, and superhydrophobic/superhydrophilic surfaces were investigated. The roughness structures on the superhydrophilic surface remained intact compared to those of the superhydrophobic surface. The micropatterned superhydrophobic/superhydrophilic surface was used as a scaffold of cell culture. On the micropatterned surface, the cells attached to the superhydrophilic regions in a highly selective manner, forming circular microarrays of the cells corresponding to the pattern. On the micropatterned surface with pattern distances of 200 μm between superhydrophilic regions, the cells adhered on the superhydrophilic regions and partly extended to the neighboring cells. In contrast, when the pattern distances between the superhydrophilic regions were more than 400 μm, the cells did not extend to the neighboring cells. Cell adhesion behaviors on superhydrophobic and superhydrophilic surfaces were also examined. The cells adhered and proliferated on both superhydrophobic and superhydrophilic surfaces. However, on the superhydrophobic surface, constant contact to facilitate cell division and proliferation was required. On the other hand, the cells easily adhered and proliferated on the superhydrophilic surface immediately after seeding. These differences in cell adhesion behavior induced site-selective cell adhesion on the superhydrophilic regions. Furthermore, protein adsorption behavior that plays an important role in cell adhesion on flat hydrophobic and hydrophilic surface was also examined. The amounts of the protein adsorption on the flat hydrophilic surface were much greater than those on the flat hydrophobic surface. © 2010 American Chemical Society.


Funahashi R.,Japan National Institute of Advanced Industrial Science and Technology
Science of Advanced Materials | Year: 2011

Oxide thermoelectric materials are considered to be promising ones because of their durability against high temperature, cost, no content of toxic elements, and so on. We have produced many types of modules using p-type Ca3Co4O9 (Co-349) and n-type CaMnO3 (Mn-113). The Co-349/Mn-113 modules show 4.2 kW/m2 of power density against heated surface area. In order to enhance power generation and conversion efficiency, cascaded modules consisting of oxide and Bi2Te3 modules. Thermoelectric units have been produced by stacking a heat collection fin, oxide and Bi2Te3 based thermoelectric modules, and water jacket for cooling. Each unit includes 4 pieces of oxide/Bi2Te3 cascaded modules. The surface area of the unit is 140 mm×140 mm. Thermoelectric power generation test was carried out using a kerosene burner. Temperature around the heat collection fin and at the hot side of the oxide module reached about 1373 K and 943 K, respectively. Out put power from one unit is 49 W. © 2011 American Scientific Publishers.


Sun Z.M.,Japan National Institute of Advanced Industrial Science and Technology
International Materials Reviews | Year: 2011

The MAX phases are a group of layered ternary compounds with the general formula Mnz1AXn (M: early transition metal; A: group A element; X: C and/or N; n=1-3), which combine some properties of metals, such as good electrical and thermal conductivity, machinability, low hardness, thermal shock resistance and damage tolerance, with those of ceramics, such as high elastic moduli, high temperature strength, and oxidation and corrosion resistance. The publication of papers on the MAX phases has shown an almost exponential increase in the past decade. The existence of further MAX phases has been reported or proposed. In addition to surveying this activity, the synthesis of MAX phases in the forms of bulk, films and powders is reviewed, together with their physical, mechanical and corrosion/oxidation properties. Recent research and development has revealed potential for the practical application of the MAX phases (particularly using the pressureless sintering and physical vapour deposition coating routes) as well as of MAX based composites. The challenges for the immediate future are to explore further and characterise the MAX phases reported to date and to make further progress in facilitating their industrial application. © 2011 Institute of Materials, Minerals and Mining and ASM International Published by Maney for the Institute and ASM International.


Setokuchi O.,Japan National Institute of Advanced Industrial Science and Technology
Physical Chemistry Chemical Physics | Year: 2011

On-the-fly quasi-classical trajectory calculations using the density functional method were carried out to investigate the dynamics of the HC(O)CO radical, formed by OH radical- and Cl atom-initiated reactions of glyoxal at 298 K. The energy difference between the A′ HC(O)CO radical, formed immediately after H atom abstraction, and the most stable A″ HC(O)CO radical is estimated to be 6.0 kcal mol-1. The surplus energy followed by relaxation from A′ HC(O)CO to A″ HC(O)CO goes to internal energy of the nascent HC(O)CO radicals and causes prompt decomposition into HCO + CO. The average internal energy partitioned into the HC(O)CO radical is higher in the OH reaction than in the Cl reaction, in accordance with exothermicity of the reactions. A fraction of the nascent HC(O)CO radicals (91% for the OH reaction and 47% for the Cl reaction) promptly decomposes into HCO and CO within 2.5 ps. The remaining HC(O)CO radicals, which do not undergo prompt decomposition, decompose thermally or add with O2 in the presence of O2. I re-evaluated the previous two experiment results of the product yield ratio [CO]/[CO2] vs. [O2]-1 in the Cl atom-initiated reaction, in light of the reaction mechanism involving prompt decomposition. The two results give 9.5 × 106 s -1 and 1.08 × 107 s-1 for the thermal decomposition rate and 47% and 41% for the fraction of prompt decomposition in the Cl atom-initiated reaction, in good agreement with the present trajectory calculation. © the Owner Societies. 2011.


Shigi N.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Biological Chemistry | Year: 2012

Posttranslational modification of proteins with ubiquitin and ubiquitin-like proteins plays important regulatory roles in eukaryotes. Although a homologous conjugation system has recently been reported in Archaea, there is no similar report in Bacteria. This report describes the identification of a ubiquitin-like conjugation system in the bacterium Thermus thermophilus. A series of in vivo analyses revealed that TtuB, a bacterial ubiquitin-like protein that functions as a sulfur carrier in tRNA thiouridine synthesis, was covalently attached to target proteins, most likely via its C-terminal glycine. The involvement of the ubiquitin-activating enzyme-like protein TtuC in conjugate formation and the attachments of TtuB to TtuC and TtuA, which are proteins required for tRNA thiouridine synthesis, were demonstrated. Mass spectrometry analysis revealed that lysine residues (Lys-137/Lys-226/Lys-229) of TtuA were covalently modified by the C-terminal carboxylate of TtuB. Intriguingly, a deletion mutant of a JAMM (JAB1/MPN/Mov34 metalloenzyme) ubiquitin isopeptidase homolog showed aberrant TtuB conjugates of TtuC and TtuA and an ∼50% decrease in thiouridine amounts in tRNA. These results would support the hypothesis that thiouridine synthesis is regulated by TtuB-conjugation. © 2012 by The American Society for Biochemistry and Molecular Biology, Inc.


Gaj T.,Scripps Research Institute | Guo J.,Scripps Research Institute | Kato Y.,Scripps Research Institute | Kato Y.,Japan National Institute of Advanced Industrial Science and Technology | And 2 more authors.
Nature Methods | Year: 2012

Zinc-finger nucleases (ZFNs) are versatile reagents that have redefined genome engineering. Realizing the full potential of this technology requires the development of safe and effective methods for delivering ZFNs into cells. We demonstrate the intrinsic cell-penetrating capabilities of the standard ZFN architecture and show that direct delivery of ZFNs as proteins leads to efficient endogenous gene disruption in various mammalian cell types with minimal off-target effects. © 2012 Nature America, Inc. All rights reserved.


Ogura T.,Japan National Institute of Advanced Industrial Science and Technology
Biochemical and Biophysical Research Communications | Year: 2014

The high-resolution structural analysis of biological specimens by scanning electron microscopy (SEM) presents several advantages. Until now, wet bacterial specimens have been examined using atmospheric sample holders. However, images of unstained specimens in water using these holders exhibit very poor contrast and heavy radiation damage. Recently, we developed the frequency transmission electric-field (FTE) method, which facilitates the SEM observation of biological specimens in water without radiation damage. However, the signal detection system presents low sensitivity. Therefore, a high EB current is required to generate clear images, and thus reducing spatial resolution and inducing thermal damage to the samples. Here a high-sensitivity detection system is developed for the FTE method, which enhances the output signal amplitude by hundredfold. The detection signal was highly enhanced when voltage was applied to the metal layer on silicon nitride thin film. This enhancement reduced the EB current and improved the spatial resolution as well as the signal-to-noise ratio. The spatial resolution of a high-sensitive FTE system is 41 nm, which is considerably higher than previous FTE system. New FTE system can easily be utilised to examine various unstained biological specimens in water, such as living bacteria and viruses.


Miyadera T.,Japan National Institute of Advanced Industrial Science and Technology
International Journal of Quantum Information | Year: 2011

The "semiquantum" key distribution protocol introduced by Zou et al. is examined. The protocol while using two-way quantum communication requires only Bob to be fully quantum. We derive a trade-off inequality between information gained by Eve and the disturbance observed by legitimate users. It guarantees that Eve cannot obtain large information if the disturbance is sufficiently small. © 2011 World Scientific Publishing Company.


Okubo M.,Japan National Institute of Advanced Industrial Science and Technology | Li C.H.,University of Florida | Talham D.R.,University of Florida
Chemical Communications | Year: 2014

We demonstrate that core-shell nanoparticles consisting of two different Prussian blue analogues, one high capacity and the other robust, can provide enhanced rate capability as cathode materials in sodium-ion batteries. © The Royal Society of Chemistry.


Kouzuma A.,Tokyo University of Pharmacy and Life Science | Kato S.,Japan National Institute of Advanced Industrial Science and Technology | Watanabe K.,Tokyo University of Pharmacy and Life Science
Frontiers in Microbiology | Year: 2015

Microbes are ubiquitous in our biosphere, and inevitably live in communities. They excrete a variety of metabolites and support the growth of other microbes in a community. According to the law of chemical equilibrium, the consumption of excreted metabolites by recipient microbes can accelerate the metabolism of donor microbes. This is the concept of syntrophy, which is a type of mutualism and governs the metabolism and growth of diverse microbes in natural and engineered ecosystems. A representative example of syntrophy is found in methanogenic communities, where reducing equivalents, e.g., hydrogen and formate, transfer between syntrophic partners. Studies have revealed that microbes involved in syntrophy have evolved molecular mechanisms to establish specific partnerships and interspecies communication, resulting in efficient metabolic cooperation. In addition, recent studies have provided evidence suggesting that microbial interspecies transfer of reducing equivalents also occurs as electric current via biotic (e.g., pili) and abiotic (e.g., conductive mineral and carbon particles) electric conduits. In this review, we describe these findings as examples of sophisticated cooperative behavior between different microbial species. We suggest that these interactions have fundamental roles in shaping the structure and activity of microbial communities. © 2015 Kouzuma, Kato and Watanabe.


Kimura T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Nanoscience and Nanotechnology | Year: 2013

This paper reviews the development of nonsiliceous porous hybrids, espetially a new family of surfactant assisted mesoporous metal organophosphonates (MOPs) prepared by the reactions between metal sources and bisphosphonates. This synthetic concept was proved by successful construction of aluminium organophosphonate (AOP) frameworks around supramolecular assembly mediated mesopores. In AOP-type materials, a series of ordered mesoporous materials can be obtained after optimizing the synthetic conditions including elimination of oligomeric surfactants and triblock copolymers. Water adsorption properties over the AOP-type materials were exceptional and promising as high-performance devise materials in gas heat-pomp and desiccant systems. A variety of ordered mesoporous titanium organophosphonates (TOPs) have also been prepared with investigation on multi-functions in liquid phases (removal of toxic heavy metal ions, photodegradation of organic pollutants, CO2 capture, chromatographic separation, etc.). Possibility to combine both functions due to inorganic units and organic groups has so far been explored. Through further development of processing and engineering methodology with the structural (mesoscale), compositional (inorganic and organic parts), and morphological (macroscale) designs, nonsiliceous MOP-type porous materials will widely be developed for potential and practical applications. Copyright © 2013 American Scientific Publishers.


Ohashi H.,Japan National Institute of Advanced Industrial Science and Technology | Omura I.,Kyushu Institute of Technology
IEEE Transactions on Electron Devices | Year: 2013

The modern power electronics era started with the commercialization of the silicon-controlled rectifier in 1957, since when power electronics systems have been installed in a wide range of applications from appliances to traction and utility systems as the technology has advanced. Meanwhile, simulation tools have played an important role in the research and development of power semiconductors and power electronics systems. As power devices and power electronics become increasingly important technologies in today's electric society, it is worth examining the overall integration of power electronics design. This paper reviews the history of simulation technology with reference to power device modeling and discusses the future of power electronics system design. © 1963-2012 IEEE.


Morita H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Photopolymer Science and Technology | Year: 2013

In the past 40 years, many kinds of simulation methods of micro phase separation of block copolymer were proposed. Each technic has some features derived from the original theory, and has strong and weak points in each simulation. We have developed the simulation software OCTA and performed the application study of OCTA to analyze the micro phase separated structure. In this paper, these simulation technics for micro phase separation of block copolymer are explained as a showcase of those technics from the point of view of DSA analysis. The advantages and disadvantages of these methods in the application study of DSA are indicated. I hope that this paper becomes the compass to select the suitable simulation method to analyze each DSA problem. © 2013SPST.


Akinaga H.,Japan National Institute of Advanced Industrial Science and Technology
Japanese Journal of Applied Physics | Year: 2013

Nanoelectronics is a fundamental technology that supports industry and society. Recently, new nanomaterials and nanostructures have been incorporated into device fabrication processes, leading to significant developments in nanoelectronics. In this review, the current status and future prospects of the research and development of functional oxide devices, in which a phase transition in strongly correlated electron systems and a current-induced redox reaction are utilized, are discussed as typical examples of recent developments. In addition, a scheme for research and development is proposed to accelerate the development of ecosystem in the field of nanoelectronics by systematizing the technologies related to new materials and structures. © 2013 The Japan Society of Applied Physics.


Kim Y.,Hokkaido University | Wada M.,Japan National Institute of Advanced Industrial Science and Technology | Tamaoki N.,Hokkaido University
Journal of Materials Chemistry C | Year: 2014

A cholesteric ester dimer-dicholesteryl icosanedioate-was examined for color imaging. Cholesterol was introduced as one of the dopants which performed an important role reducing phase transition temperatures. The other dopants, 4,4′-dialkoxyazobenzene and 4,4′-dialkoxybiphenyl promoted formation of smectic domains in cholesteric phases which resulted in the expansion of the reflective band shift over the whole visible region. In particular, the photo-responsive dopant 4,4′-dialkoxyazobenzene allowed us to realize reversible RGB color tuning of the cholesteric film by both photon and thermal modes. The trans-cis photoisomerization led to a cholesteric pitch change which resulted in reflective color change, and recorded optical images that have been stable for more than 8 months in a glassy solid film state. © 2014 The Royal Society of Chemistry.


Negishi H.,Japan National Institute of Advanced Industrial Science and Technology
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan | Year: 2014

A relative dielectric constant of a solvent is important for the electrophoretic deposition (EPD) suspension, and when the electrical resistance of the solvent is high, a large quantity of material is expected to be deposited. In this study, ethylperfluorobutylether (EFE), which is a kind of hydrofluoroether, was applied as the solvent for preparing a particle suspension for the EPD. EFE has the advantages of being polar, non-flammable, and having high electrical insulation properties. Silica powder was selected as the deposition material. When EFE is used, unlike when acetone-based EPD suspension was used, the amount deposited remains the same, but power consumption is 1/2,000 or less. Depending on conditions, power consumption is reducible even to 1/200,000. Thus, highly efficient EPD with ultra power saving ability was achieved. In addition, this process is extremely safe as EFE is nonflammable, removing the hazard of ignition. As the specific gravity of EFE is large, sedimentation of inorganic particles is slow; therefore, the dispersibility is excellent, and highly uniform coatings can be obtained. Unlike water-based EPD suspensions, the application of a high voltage is possible. In the present study, the deposition behavior was no different from that for conventional EPD, being controllable by varying the applied voltage, deposition time, and particle concentration. © 2014 The Ceramic Society of Japan. All rights reserved.


Morita H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Photopolymer Science and Technology | Year: 2014

In 2002, the simulation software system for high functional polymeric material OCTA is released. OCTA is the general purpose simulator and each multi-scale-level simulation can be easily done. Recently, we have applied our OCTA system to the problems of lithography. In this paper we discuss the applicability of OCTA system to the simulations for lithography. Two kinds of applicability are discussed. One is the development and the rinse process simulations, and another is the directed self assembly simulation. In the former study, LER can be discussed using OCTA simulation. In the latter study, many kinds of coarse-grained models can be applicable for the DSA simulation using OCTA. These wide applicability are discussed in this paper. © 2014SPST.


Kikkawa Y.,Japan National Institute of Advanced Industrial Science and Technology
Polymer Journal | Year: 2013

We present a review of our recent research on the formation of two-dimensional (2D) nanopatterns via self-assembly and their transformations by external stimuli. The proper design and synthesis of functional molecules and the ability to follow their integrations on a surface would allow the effective use of their nanofunctions to produce novel nanomaterials and devices. In this context, we synthesized stimuli-responsive molecules that contain alkyl chain units, which act as not only the adsorption unit onto the substrate but also as the intermolecular interaction site. The 2D molecular arrangements were then directly visualized using scanning tunneling microscopy at the solid/liquid interface. Thermal treatment, metal coordination and ultraviolet irradiation induced chemical structural conversions of the individual molecules, which resulted in the transformations of the 2D structures. © 2013 The Society of Polymer Science, Japan (SPSJ) All rights reserved.


Murakami H.,Geological Survey of Japan | Ishihara S.,Japan National Institute of Advanced Industrial Science and Technology
Ore Geology Reviews | Year: 2013

Indium-bearing tin-polymetallic base metal deposits in Japan (Toyoha, Ashio and Akenobe), China (Dulong and Dachang), and Bolivia (Potosi, Huari Huari, Bolivar and Porco), were studied using femto-second Laser Ablation ICPMS (fsLA-ICPMS) and EPMA analyses for major and minor elements in sphalerite, paying special attention to In concentrations. Sphalerite is a principal mineral in these tin-polymetallic deposits and a broad range of In concentration is measured in the ores. There are distinct differences in mode of occurrence of the sphalerite and the distribution of In. The highest In concentration (up to 18. wt.%) occur as a Zn-In mineral within black sphalerite zones in an oscillatory-zoned sphalerite from the Huari Huari deposits. Additionally, jamesonite from the Huari Huari deposit also contains anomalous In values, ranging from several hundreds to thousands μg/g. Sphalerite from the Toyoha and the other Bolivian deposits are characterized by oscillatory and chemical zoning, whereas those from Akenobe and the Chinese deposits are represented by homogeneous distribution of In. The 1000In/Zn values of sphalerite are in good agreement with those of the ore grade for each of the selected tin polymetallic deposits indicating that sphalerite is the principal host of In. The In-bearing sphalerite principally involves the combined coupled substitutions (2Zn2+)↔(Cu+, In3+), (3Zn2+)↔(Cu+, Ag+, Sn4+) and (3Zn2+)↔(2Cu+, Sn4+). The first of these is apparent in sphalerite from Huari Huari and Bolivar, whereas the second is prominent in sphalerite from Toyoha, Ashio, Potosi, Porco and Dachang. Akenobe and Dulong sphalerite features the dominant coupled substitution of (2Zn2+)↔(Cu+ or Ag+, In3+), owing to their poor Sn content. Occasionally, sub-micron inclusions of minerals such as stannite and Pb-Sb-bearing sulfides can occur in sphalerite, contributing to high Cu-Sn and high-Ag contents, respectively. The observed correlations of each element in the In-Cu-Ag-Sn-bearing sphalerite can be proposed as a fundamental reason for the indium enrichment related to sulfur-rich oxidized magmatism. In addition, the Ag content in sphalerite is considered a possible indicator of formation depth, which ranges from plutonic to subvolcanic environments. © 2013 Elsevier B.V.


Tsujita T.,Ehime University | Shintani T.,Ehime Institute of Industrial Technology | Sato H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Agricultural and Food Chemistry | Year: 2013

Using α-amylase inhibition as a separation guide, polyphenolic compounds from almond (Prunus dulcis) seed skin were purified using ultrafiltration and Sephadex LH-20 and ODS columns. The purified fraction specifically and strongly inhibited α-amylase; the IC50 value was 2.2 μg/mL for pig pancreatic α-amylase. The fraction contained about 62% of the total polyphenols, 33.8% flavanol-type tannins and 30% procyanidins. Oral administration of the polyphenol fraction to rats fed corn starch significantly suppressed an increase in blood glucose levels and area under the curve (AUC), in a dose-dependent manner. High-resolution MALDI-TOF mass spectra showed that the structure of this sample is a series of polyflavan-3-ol polymers composed of catechin/epicatechin units and gallocatechin/epigallocatechin units up to 11-mer with several interflavanoid ether linkages. The results suggest almond seed skin contains highly polymerized polyphenols with strong α-amylase inhibitory activity, which retard absorption of carbohydrate. © 2013 American Chemical Society.


Tsuchida H.,Japan National Institute of Advanced Industrial Science and Technology
Optics Letters | Year: 2011

I propose and demonstrate the use of the recirculating delayed self-heterodyne (DSH) method for measuring FM noise power spectral densities (PSDs), which are the most fundamental measure characterizing the spectral purity of laser sources. By analyzing the DSH beat signals with 1, 10, and 160km delays, the FM noise PSD of a narrowlinewidth fiber laser is evaluated for Fourier frequency range between 10Hz and 100 kHz, which exhibits flicker noise as the dominant contribution. © 2011 Optical Society of America.


Yamazoe H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Biomedical Materials Research - Part A | Year: 2012

A functional substrate capable of regulating protein adsorption was prepared using a crosslinked albumin (cl-albumin) film for use in the fabrication of protein micropatterns. The adsorption of proteins with different characteristics onto cl-albumin film, including serum proteins, serum albumin, and lysozyme, was investigated using a quartz crystal microbalance. The results showed that surfaces coated with cl-albumin film are highly resistant to protein adsorption, regardless of protein charge and rigidity. In addition, this adsorption-resistance property can be easily converted to promote protein adsorption by exposing the cl-albumin film to a charged polymer solution. By combining the convertible surface property of cl-albumin film and inkjet printing techniques, a precise protein micropattern was successfully fabricated on the substrate. Protein adsorption onto the wall surface of microchannels could also be suppressed or promoted by coating the surface with cl-albumin film. This approach will aid in the development of biomaterials carrying protein micropatterns, such as biosensors, biochips, and cellular scaffolds. Copyright © 2011 Wiley Periodicals, Inc.


Kimura T.,Japan National Institute of Advanced Industrial Science and Technology
Chemical Record | Year: 2016

A large number of periodic mesoporous materials have been reported using amphiphilic organic molecules with increasing development of synthetic methods for mesostructural, morphological, and compositional designs. The evaporation-induced self-assembly (ESIA) process to fabricate ordered mesoporous films is one of the most essential synthetic methods, which has extensively been applied for obtaining a wide variety of samples (e.g., films and monoliths, including powders). It contains complicated physical variations and chemical reactions, but has been simply explained by several research groups. However, a current, exact understanding of such complicated systems should be given with respect to all the variations and reactions. In this article, I have mainly surveyed the exact EISA process by considering the difference between simple and controlled EISA processes on the basis of my own experiments. I believe that the insights are consequently helpful for obtaining highly ordered mesoporous materials with demanded morphologies. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Kimura M.,Japan National Institute of Advanced Industrial Science and Technology
International Journal of Psychophysiology | Year: 2012

Since the discovery of an event-related brain potential (ERP) component, auditory mismatch negativity (auditory MMN), there has been a long-lasting debate regarding the existence of its counterparts in other sensory modalities. Over the past few decades, several studies have confirmed the existence of mismatch negativity in the visual modality (visual MMN) and have revealed the various characteristics of visual MMN. In the present review, a full range of visual MMN studies are overviewed from the perspective of the predictive framework of visual MMN recently proposed by Kimura et al. (2011b). In the first half, the nature of visual MMN is reviewed in terms of (1) typical paradigm and morphologies, (2) underlying processes, (3) neural generators, and (4) functional significance. The main message in this part is that visual MMN is closely associated with the unintentional prediction of forthcoming visual sensory events on the basis of abstract sequential rules embedded in the temporal context of visual stimulation (i.e., "unintentional temporal-context-based prediction in vision"). In the second half, the nature of the unintentional prediction is discussed in terms of (1) behavioral indicators, (2) cognitive properties, and (3) neural substrates and mechanisms. As the main message in this part, I put forward a hypothetical model, which suggests that the unintentional prediction might be implemented by a bi-directional cortical network that includes the visual and prefrontal areas. © 2011 Elsevier B.V.


Ogura T.,Japan National Institute of Advanced Industrial Science and Technology
Biochemical and Biophysical Research Communications | Year: 2010

Analytical tools of nanometre-scale resolution are indispensable in the fields of biology, physics and chemistry. One suitable tool, the soft X-ray microscope, provides high spatial resolution of visible light for wet specimens. For biological specimens, X-rays of water-window wavelength between carbon (284 eV; 4.3 nm) and oxygen (540 eV; 2.3 nm) absorption edges provide high-contrast imaging of biological samples in water. Among types of X-ray microscope, the transmission X-ray microscope using a synchrotron radiation source with diffractive zone plates offers the highest spatial resolution, approaching 15-10 nm. However, even higher resolution is required to measure proteins and protein complexes in biological specimens; therefore, a new type of X-ray microscope with higher resolution that uses a simple light source is desirable. Here we report a novel scanning-electron generation X-ray microscope (SGXM) that demonstrates direct imaging of unstained wet biological specimens. We deposited wet yeasts in the space between two silicon nitride (Si3N4) films. A scanning electron beam of accelerating voltage 5 keV and current 1.6 nA irradiates the titanium (Ti)-coated Si3N4 film, and the soft X-ray signal from it is detected by an X-ray photodiode (PD) placed below the sample. The SGXM can theoretically achieve better than 5 nm resolution. Our method can be utilized easily for various wet biological samples of bacteria, viruses, and protein complexes. © 2009 Elsevier Inc. All rights reserved.


Mekaru H.,Japan National Institute of Advanced Industrial Science and Technology
Microelectronic Engineering | Year: 2015

In a conventional method where patterned photoresist structures are in direct contact with the metal-cylindrical roller's surface employing a relief printing, the adhesion area normally does not have a sufficient strength to hold against a subsequent contact pressure and a moment of force that are encountered during the rotation of the roller. Therefore, to improve the robustness of the protuberant photoresist structures, we introduced a residual layer of photoresist (not exposed to any UV light), where the protuberant photoresist structures with sloped sidewalls were cemented onto the residual layer. And then this whole system was used to cover around the surface of the metal-cylindrical-roller. It has been well observed, and reported that a laser drawing system using grayscale lithography leaves traces on photoresist surfaces. However, these traces can now be removed by performing a reflow process under the optimal conditions. As a result of investigating the shape's transition of the protuberant photoresist structures at different reflow times, and of the durability experiment of 10 times press operations using a flat press-plate, the practicality of our technique combining the grayscale laser lithography and the reflow process was confirmed. © 2015 Elsevier B.V. All rights reserved.


Fukuda J.-I.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010

It is known that, in the order-parameter space S2 / Z2 (a typical example being a uniaxial nematic liquid crystal in three dimensions), a -1/2 wedge disclination line and a +1/2 one are topologically equivalent and can thus be transformed continuously into each other. Here we report the realization of this transformation in a simulation of a cholesteric blue phase under an electric field. © 2010 The American Physical Society.


Fukuda J.-I.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010

We discuss, with the aid of numerical calculations based on a Landau-de Gennes theory, the stabilization of a blue phase in chiral liquid crystals by introducing a guest component. Our argument is based on a common speculation that cores of disclination lines with higher free-energy density are replaced by the guest component. We assume that the guest component forms sharp interfaces with the liquid crystal (strong segregation). We show that, by a suitable choice of materials with small interfacial tension, a guest component of volume fraction less than 10% drastically increases the temperature range of thermodynamic stability of a blue phase, in agreement with experiments. © 2010 The American Physical Society.


Yokokawa H.,Japan National Institute of Advanced Industrial Science and Technology
Solid State Ionics | Year: 2012

Roles of Secondary Ion Mass Spectrometry and the local thermodynamic equilibrium approximation are discussed in understanding high temperature electrochemical processes. Fundamental issues are first considered on metal dense electrode (Pt/Au) and oxide electrolyte (YSZ/GDC) systems; the so-called three phase boundary (TPB) mechanism is dominant for YSZ systems, whereas for the GDC systems, a new proton/water mechanism is dominant; protons play an important role in a such way that the cathodic reaction of protons to form water vapors takes place at TPBs, while evaporated water vapors are transported on the GDC surface; oxide ions are transported to the anode and protons are circulated to the TPBs of the cathode; another effect of water vapors is to enhance oxygen isotope exchange reactions over a whole area of surface and a resulting flow of 18O inside GDC masks the charge transfer process in the SIMS analyses. A local proton flow in the proton/water mechanism provides a drastic change in the distribution of chemical potential of water vapors under the dense electrodes, leading to the pore formation or the non-homogenized cation distribution. Concerning industrial issues, two degradation topics are analyzed on drastic changes in chemical potential distribution caused by electrode reactions or by non-uniform flows of oxide ions inside electrolyte. © 2012 Elsevier B.V.


Asai Y.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2015

We demonstrate that there is a strong correlation between the current noise and the inelastic tunneling spectrum of the vibronic current through nanoscale objects. The voltage derivative of the electron-phonon contribution to the noise is found to scale strongly with the contribution to the dynamical conductance when the partition noise vanishes. The scaling relation fails when the partition noise is maximized, i.e., in the case of half transmission, whereas we still find clear vibronic structure in the voltage sweep of the current noise. We have clarified the condition for the scaling relation. The voltage sweep of the current noise can provide us a useful spectroscopy method for the nonequilibrium dynamics of electrons and phonons. © 2015 American Physical Society.


Kiryu H.,University of Tokyo | Asai K.,University of Tokyo | Asai K.,Japan National Institute of Advanced Industrial Science and Technology
Bioinformatics | Year: 2012

Motivation: Measuring the effects of base mutations is a powerful tool for functional and evolutionary analyses of RNA structures. To date, only a few methods have been developed for systematically computing the thermodynamic changes of RNA secondary structures in response to base mutations. Results: We have developed algorithms for computing the changes of the ensemble free energy, mean energy and the thermodynamic entropy of RNA secondary structures for exhaustive patterns of single and double mutations. The computational complexities are O(NW 2) (where N is sequence length and W is maximal base pair span) for single mutations and O(N 2W 2) for double mutations with large constant factors. We show that the changes are relatively insensitive to GC composition and the maximal span constraint. The mean free energy changes are bounded ~7-9 kcal/mol and depend only weakly on position if sequence lengths are sufficiently large. For tRNA sequences, the most stabilizing mutations come from the change of the 5'-most base of the anticodon loop. We also show that most of the base changes in the acceptor stem destabilize the structures, indicating that the nucleotide sequence in the acceptor stem is highly optimized for secondary structure stability. We investigate the 22 tRNA genes in the human mitochondrial genome and show that non-pathogenic polymorphisms tend to cause smaller changes in thermodynamic variables than generic mutations, suggesting that a mutation which largely increases thermodynamic variables has higher possibility to be a pathogenic or lethal mutation. © The Author 2012. Published by Oxford University Press. All rights reserved.


Kosugi T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of the Physical Society of Japan | Year: 2013

Relativistic electronic properties of a nanospring under a static magnetic field are theoretically investigated in the present study. The wave equation accounting for the spin-orbit interaction is derived for the nanospring as a special case of the Pauli equation for a spin-1/2 particle confined to a curved surface under an electromagnetic field. We define the helical momentum operator and show that it commutes with the Hamiltonian owing to the helical geometry of the nanospring. The energy eigenstates are hence also the eigenstates of the helical momentum. We solve the equation numerically to obtain the surface wave functions and the energy spectra. The electronic properties are systematically examined by varying the parameters that characterize the system. It is demonstrated that either the nonzero spin-orbit interaction or the nonzero external magnetic field suffices for the occurrence of the persistent spin current on the nanospring. Two different mechanisms are shown to generate the persistent spin current. One employs the spin-orbit interaction coming from the local inversion asymmetry on the surface, while the other employs the curvature coupling with the external magnetic field. © 2013 The Physical Society of Japan.


Hayamizu K.,Japan National Institute of Advanced Industrial Science and Technology | Aihara Y.,Samsung
Solid State Ionics | Year: 2013

The sulfide based solid electrolyte (Li2S)7(P 2S5)3 has large ionic conductivity, and thus its application in solid-state lithium rechargeable batteries as an electrolyte has been developed. We observed the 7Li and 31P nuclear magnetic resonance (NMR) spectra of crystallized (Li2S) 7(P2S5)3 in the steady state and found that narrow and broad components coexist in wide temperature range of the 7Li resonance. The measurement of 7Li ion diffusion was performed for the narrow component between 303 and 353 K by the pulsed-gradient spin-echo (PGSE) NMR method. Lithium ion diffusion scattered in a polydispersive manner and the apparent diffusion constants of the Li+ (D Li) varied depending on measurement conditions at a certain temperature. The temperature-dependent ionic conductivity was observed from 263 to 353 K and the activation energy was 31.4 kJ mol- 1 for the crystallized (Li2S)7(P2S5) 3. The DLi evaluated from ionic conductivity using the Nernst-Einstein relation was consistent with the scattering apparent D Li observed by the PGSE NMR method. The translational movement of Li+ observed by the PGSE NMR is extremely complex. Within a short distance and a short period, Li+ ions move quickly and slow down with time and distance. This is the first trial to measure the lithium diffusion directly for continuous space in the solid electrolyte. © 2013 Elsevier B.V. All rights reserved.


Ogawa H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Alloys and Compounds | Year: 2011

Hydrogen absorption in b.c.c. and f.c.c. nanoparticles was investigated using molecular dynamics simulation with systematic variance of the M-H potential function parameters. Three patterns of hydrogen distribution in nanoparticles, non-absorbing, homogeneous absorbing, and forming a hydrogen-rich surface layer were observed depending on the assumed potential parameter values. Simulated P-C isotherms of nanoparticles show similarity with experimental ones. Variation of the metallic lattice because of hydrogenation was observed as transitions to b.c.t., icosahedral, or amorphous phases. Generation of grain boundary was observed to accompany these lattice transformations. The simulated P-C isotherms and structural variation were discussed in relation to the assumed potential parameters, temperature, and particle size. © 2010 Elsevier B.V. All rights reserved.


Enomoto M.,Japan National Institute of Advanced Industrial Science and Technology | Morita A.,Tohoku University | Kuwahara S.,Tohoku University
Angewandte Chemie - International Edition | Year: 2012

Succinct and stereoselective: A high-yielding two-step indole ring installation comprising the Stille cross-coupling and a PdII-mediated oxidative heterocyclization was exploited in a concise total synthesis of paspalinine. The trans-anti-trans CDE fused ring system of the heptacyclic natural product was established highly stereoselectively through hydroxy-directed cyclopropanation and allylic selenoxide rearrangement. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Fedorov D.G.,Japan National Institute of Advanced Industrial Science and Technology | Kitaura K.,Kobe University
Chemical Physics Letters | Year: 2014

We developed a dual basis approach within the fragment molecular orbital formalism enabling efficient and accurate use of large basis sets. The method was tested on water clusters and polypeptides and applied to perform geometry optimization of chignolin (PDB: 1UAO) in solution at the level of DFT/6-31++G*, obtaining a structure in agreement with experiment (RMSD of 0.4526 Å). The polarization in polypeptides is discussed with a comparison of the α-helix and β-strand. © 2014 Elsevier B.V. All rights reserved.


Tsuzuki S.,Japan National Institute of Advanced Industrial Science and Technology | Sato N.,Kyoto University
Journal of Physical Chemistry B | Year: 2013

Intermolecular interaction in the 1,2,5-chalcogenadiazole dimers was studied by ab initio molecular orbital calculations. Estimated CCSD(T) interaction energies for the thia-, selena- and tellura-diazole dimers are -3.14, -5.29, and -12.42 kcal/mol, respectively. The electrostatic and dispersion interactions are the major sources of the attraction in the dimers, although it was claimed that the orbital mixing (charge-transfer interaction) was the most prominent contribution to the stabilization. The induction (induced polarization) interaction also contributes largely to the attraction in the telluradiazole dimer. The large electrostatic and induction interactions are responsible for the strong attraction in the telluradiazole dimer. The short-range (orbital-orbital) interaction (sum of the exchange-repulsion and charge-transfer interactions) is repulsive. The directionality of the interactions increases in order of S < Se < Te. The electrostatic interaction is mainly responsible for the directionality. The strong directionality suggests that the chalcogen-nitrogen interaction plays important roles in controlling the orientation of molecules in those organic crystals. The nature of the chalcogen-nitrogen interaction in the chalcogenadiazole dimers is similar to that of the halogen bond, which is an electrostatically driven noncovalent interaction. © 2013 American Chemical Society.


Nakagawa S.,RIKEN | Hirose T.,Japan National Institute of Advanced Industrial Science and Technology
Cellular and Molecular Life Sciences | Year: 2012

The nucleus of higher eukaryotes, such as humans and mice, is compartmentalized into multiple nuclear bodies, an organization that allows for the regulation of complex gene expression pathways that are characteristic of these organisms. Paraspeckles are recently discovered, mammalian-specific nuclear bodies built on a long, non-protein-coding RNA, NEAT1 (nuclear-enriched abundant transcript 1), which assembles various protein components including RNA-binding proteins of the DBHS (Drosophila behavior and human splicing) family. Paraspeckles have been proposed to control several biological processes, such as stress responses and cellular differentiation, but their function at the whole animal level remains unclear. In this review, we summarize a series of studies on paraspeckles that have been carried out in the decade since their discovery and discuss their physiological function and molecular mechanism. © The Author(s) 2012.


Ishida T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of the American Chemical Society | Year: 2010

Assignment of particular roles to catalytic residues is an important requirement in clearly understanding enzyme functions. Therefore, predicting the catalytic activities of mutant variants is a fundamental challenge in computational biochemistry. Although site-directed mutagenesis is widely used for studying enzymatic activities and other important classes of protein function, interpreting mutation experiments is usually difficult mainly due to side effects induced by point mutations. Because steric and, in many cases, electrostatic effects may affect the local, fine geometries conserved in wild-type proteins that are usually believed to be thermodynamically stable, simply reducing a loss in catalytic activity into clear elements is difficult. To address these important but difficult issues, we performed a systematic ab initio QM/MM computational analysis combined with MD-FEP simulations and all-electron QM calculations for the entire protein matrix. We selected chorismate mutase, one of the simplest and well-known enzymes, to discuss the details of mutational effects on the enzymatic reaction process. On the basis of the reliable free energy profiles of the wild-type enzyme and several mutant variants, we analyzed the effects of point mutations relative to electronic structure and protein dynamics. In general, changes in geometrical parameters introduced by a mutation were usually limited to the local mutational site. However, this local structural modification could affect the global protein dynamics through correlated motions of particular amino acid residues even far from the mutation site. Even for mutant reactions with low catalytic activity, transition state stabilization was observed as a result of conformational modifications and reorganization around the active site. As for the electrostatic effect created by the polar protein environment, the wild-type enzyme was most effectively designed to stabilize the transition state of the reactive substrate, and the effect of global polarization in the electronic structure was found to be a small catalytic element during the process. As electrostatic media for optimum catalysis, both wild-type and mutant variant proteins were generally robust against external electrostatic perturbations. Protein structures have a certain flexibility, which allows them to slightly modulate their conformations to maximize the transition state stabilization in response to the steric perturbations induced by mutations. © 2010 American Chemical Society.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2012

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January 2012 are reviewed. Copyright © 2012 John Wiley & Sons, Ltd.


Maekawa T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Chemical and Engineering Data | Year: 2010

Equilibrium conditions for carbon dioxide hydrates in the presence of aqueous solutions of methanol, ethanol, ethylene glycol, diethylene glycol, triethylene glycol, and glycerol were experimentally measured at temperatures ranging from (264.1 to 283.1) K and pressures up to 4.54 MPa using an isochoric method. On a mass fraction basis, the inhibiting effect on the carbon dioxide hydrate equilibria decreased in the following order: methanol > ethanol > ethylene glycol > glycerol > diethylene glycol > triethylene glycol. The order is the same as predicted by the Hammerschmidt equation. © 2010 American Chemical Society.


Fukushima M.,Japan National Institute of Advanced Industrial Science and Technology
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan | Year: 2013

Wide range of porosity in 30-90 vol% could be created into silicon carbide by employing carefully selected manufacturing methods. Two fabrication methods have been proposed and reviewed in the present paper: (1) partial sintering of submicrometer-sized silicon carbide particle with a suitable amount of sintering additive, acting as an inhibition of grain growth during sintering; (2) the use of ice crystals, as sacrificial pore formers, formed by freezing a silicon carbide particle dispersed gel body, leading to highly porous silicon carbide after sublimating ice crystals by vacuum drying and subsequently sintering. Depending on the processing route adopted, average pore size could be modulated in the range from 0.03 to 0.70 μm and 30 to 150 μm by partial sintering and gelation freezing, respectively. All fabrication methods proposed are simple, economical and versatile to produce macroporous body with tailored pore architecture and engineering porosity. © 2013 The Ceramic Society of Japan. All rights reserved.


Mathews J.P.,Pennsylvania State University | Sharma A.,Japan National Institute of Advanced Industrial Science and Technology
Fuel | Year: 2012

It has long been recognized that coal is somewhat aligned. Multiple techniques imply a structural alignment but its quantification has been challenging. Moreover, discrepancies exist among techniques as to whether low-rank coals are aligned. The extent of structural alignment for the rank range was quantified directly via image analysis of high-resolution transmission electron micrograph lattice fringes. Alignment was quantified, for each coal, by the contribution to the total fringe length within the prominent 45°of orientation over random orientation (1/4 of the possible orientations). It was evident that there is structural alignment across the rank range. Thus it is time for the community to desist from making the erroneous statement that: low-rank coals are randomly oriented. The slight orientation was similar for low-rank Beulah-Zap lignite and Illinois No. 6 bituminous coals (24% and 22%) with Pocahontas (lvb) coal showing slightly greater (39%) alignment with extensive alignment (65%) in the case of an anthracite coal. The degree of ordering is illustrated with the aid of false-color lattice fringe images and Rose diagrams. The fringe contribution 90°opposed to the maximum length contribution had the minimum or near minimum percentage length contribution for all coals except Upper Freeport and to a lesser degree Illinois No. 6. For the Upper Freeport coal the alignment is lower than expected given its mvb rank (14% over random) and is attributed to a variant of T-stacking for the small aromatic moieties sited perpendicular and between horizontal displaced fringes. © 2012 Elsevier Ltd. All rights reserved.


Okazaki Y.,Japan National Institute of Advanced Industrial Science and Technology
Journal of the Mechanical Behavior of Biomedical Materials | Year: 2014

The effects of articular head size on the wear losses of the metal insert and articular head for a metal-on-metal bearing were examined using a hip simulator manufactured to satisfy ISO 14242-1. The wear properties of metal-on-metal and metal-on-polyethylene bearings were also compared under the same conditions. The total wear losses of the metal insert and articular head decreased with increasing diameter of the metal insert in the range from 28 to 44. mm. The total wear loss was greater for a diameter of 48. mm than for a diameter of 44. mm. When the articular metal insert diameter was smaller than 44. mm, the wear loss was reduced because the contact surface pressure increased with increasing metal insert diameter. However, the increase in wear loss observed for the 48-mm-diameter insert might have been due to the considerable increase in the rotation moment with increasing insert diameter. The tendency of decreasing contact pressure calculated using the Hertzian contact stress equation nearly conformed to the change in wear loss. On the other hand, the wear loss of an artificial hip joint consisting of a cross-linked ultrahigh-molecular-weight polyethylene insert (UHMWPE) and a Co-Cr-Mo articular head was small. © 2013 Elsevier Ltd.


Frith M.C.,Japan National Institute of Advanced Industrial Science and Technology | Noe L.,French Institute for Research in Computer Science and Automation
Nucleic Acids Research | Year: 2014

Sequence similarity search is a fundamental way of analyzing nucleotide sequences. Despite decades of research, this is not a solved problem because there exist many similarities that are not found by current methods. Search methods are typically based on a seed-and-extend approach, which has many variants (e.g. spaced seeds, transition seeds), and it remains unclear how to optimize this approach. This study designs and tests seeding methods for inter-mammal and inter-insect genome comparison. By considering substitution patterns of real genomes, we design sets of multiple complementary transition seeds, which have better performance (sensitivity per run time) than previous seeding strategies. Often the best seed patterns have more transition positions than those used previously. We also point out that recent computer memory sizes (e.g. 60 GB) make it feasible to use multiple (e.g. eight) seeds for whole mammal genomes. Interestingly, the most sensitive settings achieve diminishing returns for human-dog and melanogaster-pseudoobscura comparisons, but not for human-mouse, which suggests that we still miss many human-mouse alignments. Our optimized heuristics find ∼20 000 new human-mouse alignments that are missing from the standard UCSC alignments. We tabulate seed patterns and parameters that work well so they can be used in future research. © 2014 The Author(s). Published by Oxford University Press.


Kuwauchi Y.,Osaka University | Yoshida H.,Osaka University | Akita T.,Japan National Institute of Advanced Industrial Science and Technology | Haruta M.,Tokyo Metroplitan University | Takeda S.,Osaka University
Angewandte Chemie - International Edition | Year: 2012

Despite the fragility of TiO 2 under electron irradiation, the intrinsic structure of Au/TiO 2 catalysts can be observed by environmental transmission electron microscopy. Under reaction conditions (CO/air 100 Pa), the major {111} and {100} facets of the gold nanoparticles are exposed and the particles display a polygonal interface with the TiO 2 support bounded by sharp edges parallel to the ←110→ directions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Hibino T.,Nagoya University | Shen Y.,Nagoya University | Nishida M.,Japan National Institute of Advanced Industrial Science and Technology | Nagao M.,Nagoya University
Angewandte Chemie - International Edition | Year: 2012

Ion conductor: A series of Sn 1-xA xP 2O 7 (A V=V, Nb, Ta, and Sb) compounds was synthesized, among which Sn 0.92Sb 0.08P 2O 7 (see picture) showed the highest hydroxide ion conductivity in the temperature range of 50-200 °C (0.08 S cm -1 at 100 °C and 0.05 S cm -1 at 200 °C). This high conductivity was also confirmed under fuel-cell-operating conditions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Vera-Marun I.J.,Zernike Institute for Advanced Materials | Van Wees B.J.,Zernike Institute for Advanced Materials | Jansen R.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review Letters | Year: 2014

An electric current from a ferromagnet into a nonmagnetic material can induce a spin-dependent electron temperature. Here, it is shown that this spin heat accumulation, when created by tunneling from a ferromagnet, produces a non-negligible voltage signal that is comparable to that due to the coexisting electrical spin accumulation and can give a different Hanle spin precession signature. The effect is governed by the spin polarization of the Peltier coefficient of the tunnel contact, its Seebeck coefficient, and the spin heat resistance of the nonmagnetic material, which is related to the electrical spin resistance by a spin-Wiedemann-Franz law. Moreover, spin heat injection is subject to a heat conductivity mismatch that is overcome if the tunnel interface has a sufficiently large resistance. © 2014 American Physical Society.


Miyoshi T.,University of Akron | Mamun A.,Japan National Institute of Advanced Industrial Science and Technology
Polymer Journal | Year: 2012

Isotactic-poly(1-butene) (iPB1) shows superior mechanical properties after crystal-crystal transitions. Recently, Miyoshi et al. found that crystalline stems in metastable tetragonal crystal perform uniaxial rotational diffusions accompanying side-chain conformational transitions in the fast motional limit (correlation time, 〈 τ c 〉 < 10 -7 s; Macromolecules 2010, 43, 3986-3989.). In this study, molecular dynamics in stable trigonal crystal is investigated by solid-state nuclear magnetic resonance, which indicates that crystalline stems and side-chain conformations are completely fixed up to melting points (〈 τ c 〉 > 10 s). In addition, lamellar thickness, 〈l〉 of iPB1 and a low isotacticity iPB1 (low-iPB1) with 〈mmmm〉=78%, respectively, were investigated by small-angle X-ray scattering. The low-iPB1 sample shows very week supercooling dependence of 〈l〉 (∼5 nm), whereas iPB1 shows strong supercooling dependence of 〈l〉 (10-28 nm). On the basis of molecular dynamics and 〈l〉 results, molecular dynamics effects on structures and unique mechanical property of iPB1 are discussed. © The Society of Polymer Science, Japan (SPSJ) All rights reserved.


Kobayashi T.,Japan National Institute of Advanced Industrial Science and Technology
Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition | Year: 2013

Image classification methods have been significantly developed in the last decade. Most methods stem from bag-of-features (BoF) approach and it is recently extended to a vector aggregation model, such as using Fisher kernels. In this paper, we propose a novel feature extraction method for image classification. Following the BoF approach, a plenty of local descriptors are first extracted in an image and the proposed method is built upon the probability density function (p.d.f) formed by those descriptors. Since the p.d.f essentially represents the image, we extract the features from the p.d.f by means of the gradients on the p.d.f. The gradients, especially their orientations, effectively characterize the shape of the p.d.f from the geometrical viewpoint. We construct the features by the histogram of the oriented p.d.f gradients via orientation coding followed by aggregation of the orientation codes. The proposed image features, imposing no specific assumption on the targets, are so general as to be applicable to any kinds of tasks regarding image classifications. In the experiments on object recognition and scene classification using various datasets, the proposed method exhibits superior performances compared to the other existing methods. © 2013 IEEE.


[2+2] Photocycloaddition of olefins is a very useful reaction in synthetic organic chemistry to obtain cyclobutane-containing molecules, which are almost inaccessible by other methods. The reaction, when performed in the crystalline state, occurs more efficiently and selectively than in homogeneous solution due to tight and regular molecular arrangement in the crystal state. Despite numerous examples for the solid-state [2+2] photodimerization of monoenes, however, it is still a challenge to prepare not only dimers but also higher oligomers and polymers from conjugated polyenes, which have multiple reactive double bonds in a molecule. In our recent studies of the solid-state photoreactions of α,ω-diarylpolyenes, noncovalent intermolecular interactions in crystals were effectively utilized to prealign molecules in stacking arrangements, suitable for the [2+2] reaction. With appropriate ring-substituents, [2+2] photodimerization and photopolymerization of the polyenes took place, although the degree of polymerization was relatively low. This review will describe the details of these reactions. © 2010 by the authors.


Kimura T.,Japan National Institute of Advanced Industrial Science and Technology
Physical Chemistry Chemical Physics | Year: 2013

Porous organic membranes have been utilized as hard templates not only for replication of porous macrostructures but also for fabrication of hierarchical porous solids through infiltration of precursor solutions in ordered mesoporous materials. However, such organic membranes are usually burned out as sacrificial skeletons by calcination. In addition, replicated macropores are too big to enhance properties due to inorganic oxide frameworks. In this study, when cellulose membranes were used as organic membranes, a coating/filling technology of ordered mesoporous silicas was proposed and the water adsorption-desorption properties were directly investigated by using the composite membranes after extraction of nonionic surfactants used. The composite membranes possessed enough adsorption capacity for water, which will be potentially useful for improving total energy efficiency in heat-pump and desiccant air conditioning systems. © the Owner Societies 2013.


Himeda Y.,Japan National Institute of Advanced Industrial Science and Technology | Miyazawa S.,Saitama University | Hirose T.,Saitama University
ChemSusChem | Year: 2011

The interconversion between formic acid and H 2/CO 2 using half-sandwich rhodium and ruthenium catalysts with 4,4'-dihydroxy-2,2'- bipyridine (DHBP) was investigated. The influence of substituents of the bipyridine ligand was studied. Chemical shifts of protons in bipyridine linearly correlated with Hammett substituent constants. In the hydrogenation of CO 2/bicarbonate to formate under basic conditions, significant activations of the catalysts were caused by the electronic effect of oxyanions generated by deprotonation of the hydroxyl group. Initial turnover frequencies of the ruthenium- and rhodium-DHBP complexes increased 65- and 8-fold, respectively, compared to the corresponding unsubstituted bipyridine complexes. In the decomposition of formic acid under acidic conditions, activity enhancement by the electronic effect of the hydroxyl group was observed for the ruthenium catalyst. The rhodium-DHBP catalyst showed high activity without CO contamination in a relatively wide pH range. Pressurized H 2 can be obtained using an autoclave reactor. The highest turnover frequency and number were obtained at 80°C. The catalytic system provides valuable insight into the use of CO 2 as a H 2 storage material by combining CO 2 hydrogenation with formic acid decomposition. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Hiyoshi N.,Japan National Institute of Advanced Industrial Science and Technology
Applied Catalysis A: General | Year: 2012

In this study, we have synthesized nanocrystalline sodalite and investigated its activity for the epoxidation of α,β-unsaturated ketone with hydrogen peroxide. Nanocrystalline sodalite was prepared by hydrothermal synthesis using sodium metasilicate (Na 2SiO 3·9H 2O), sodium aluminate (NaAlO 2), and sodium chloride at 423 K. The obtained samples were characterized by X-ray diffraction, the Brunauer-Emmet-Teller (BET) method using nitrogen adsorption isotherms, scanning electron microscopy (SEM), and energy dispersive X-ray analysis. The maximum BET surface area of the nanocrystalline sodalite prepared in this study was 73 m 2 g -1, and the average crystallite diameter of the sample was determined to be 47 nm by SEM. Nanocrystalline sodalite was found to promote the epoxidation of 2-cyclohexen-1-one with hydrogen peroxide. Epoxidation was observed to proceed mainly in the liquid phase and not on the surface of the nanocrystalline sodalite, and nanocrystalline sodalite was found to play a role in the pH adjustment of the liquid phase, which was required for the reaction to proceed. Further, nanocrystalline sodalite could be easily recovered by filtration after the epoxidation of 2-cyclohexen-1-one and used repeatedly for the reaction. © 2012 Elsevier B.V. All rights reserved.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems
Progress in Photovoltaics: Research and Applications | Year: 2011

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since June 2010 are reviewed. Copyright © 2010 John Wiley & Sons, Ltd.


Yabuki S.,Japan National Institute of Advanced Industrial Science and Technology
Analytical Sciences | Year: 2011

The immobilization of biomolecules is an important technique for bio-analysis, and can be applied to biosensors with both high selectivity and high sensitivity. Many researchers have developed immobilization techniques to optimize these characteristics. In the last two decades, an immobilization technique that meets the desired requirements was developed by using polyelectrolytes to form complexes, based on the electrostatic binding between polycations and polyanions. This review summarizes the techniques used for the immobilization of biomolecules by polyelectrolyte complexes; it also discusses related subjects. © 2011 The Japan Society for Analytical Chemistry.


Niki E.,Kyoto Prefectural University of Medicine | Niki E.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Clinical Biochemistry and Nutrition | Year: 2011

Lipid peroxidation induced by free radicals has been implicated in the pathogenesis of various diseases. Numerous in vitro and animal studies show that oxidative modification of low density lipoprotein (LDL) is an important initial event of atherosclerosis. Vitamin E and other antioxidants inhibit low density lipoprotein oxidation efficiently in vitro, however, human clinical trials with vitamin E have not yielded positive results. The mixed results for vitamin E effect may be ascribed primarily to the two factors. Firstly low density lipoprotein oxidation proceeds by multiple pathways mediated not only by free radicals but also by other non-radical oxidants and vitamin E is effective only against free radical mediated oxidation. Secondly, in contrast to animal experiments, vitamin E is given at the latter stage where oxidation is no more important. Free radicals must play causal role in pathogenesis of atherosclerosis and vitamin E should be effective if given at right time to right subjects. ©2011 JCBN.


Mizumoto T.,Tokyo Institute of Technology | Takei R.,Japan National Institute of Advanced Industrial Science and Technology | Shoji Y.,Tokyo Institute of Technology
IEEE Journal of Quantum Electronics | Year: 2012

Waveguide optical isolators are investigated for an application to integrated optics. A nonreciprocal loss shift isolator has the advantage of high compatibility with optical active devices. The interferometric waveguide optical isolator that uses nonreciprocal phase shift brought about by the first-order magneto-optic effect is applicable to a variety of waveguide platforms. In a silicon-on-insulator (SOI) waveguide, the low refractive index of buried oxide layer enhances the magneto-optic phase shift, which contributes to reduce the device size of isolator. We developed the surface activated direct bonding technique to integrate a magneto-optic garnet crystal onto dissimilar crystals. The performance of SOI waveguide optical isolator was demonstrated with an optical isolation of 21 dB at a wavelength of 1559 nm. © 2006 IEEE.


Yoneya M.,Japan National Institute of Advanced Industrial Science and Technology
Chemical Record | Year: 2011

An analogy of block copolymer micro-segregation as a low-molecular weight nanostructured liquid crystal (LC) was tested with recently found columnar and cubic phase-forming LC molecules, to clarify the broader applicability of the analogy as a molecular design principle. We found that the copolymer analogy principle also works well for new micellar cubic phase-forming molecules. For bicontinuous cubic phase-forming 1,2-bis(4′-n-alkoxybenzoyl)hydrazines (BABH-n) compounds that cover a much broader core fraction range than that predicted by the copolymer analogy, we propose hierarchical preferential orientation as an additional mechanism for their cubic range broadening. For azo-dichiral molecules that also do not fit with the above principle, we propose chiral segregation as an alternative origin for their cubic phase formation. © 2011 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.


Yamada H.,Japan National Institute of Advanced Industrial Science and Technology
Japanese Journal of Applied Physics | Year: 2012

A model of microwave plasma chemical vapor deposition for the growth of diamond crystals has been developed. The model focuses on the characteristics of bulk plasma, while atomic-scale simulation is also utilized to determine the boundary conditions of heavier species. In comparison with recent numerical studies of microwave plasma chemical vapor depositions by several groups, the present model places emphasis on the treatment of chemistry among reactive (H, C, N) species as well as the dynamics of species under practical configuration, i.e., configuration close to an actual apparatus, where the governing equations are reduced to be as simple as possible under acceptable assumptions. Results are consistent with several preceding reports. This suggests the validity of the assumptions. The two-dimensional distributions of not only the various hydrocarbon species but also the nitrogen-related species are shown for the first time under the practical configuration. © 2012 The Japan Society of Applied Physics.


Kondoh J.,Japan National Institute of Advanced Industrial Science and Technology | Lu N.,Pacific Northwest National Laboratory | Hammerstrom D.J.,Pacific Northwest National Laboratory
IEEE Transactions on Power Systems | Year: 2011

This paper investigates the possibility of providing aggregated regulation services with small loads, such as water heaters or air conditioners. A direct-load control algorithm is presented to aggregate the water heater load for the purpose of regulation. A dual-element electric water heater model is developed, which accounts for both thermal dynamics and users' water consumption. A realistic regulation signal was used to evaluate the number of water heaters needed and the operational characteristics of a water heater when providing 2-MW regulation service. Modeling results suggest that approximately 33000 water heaters are needed to provide a 2-MW regulation service 24 hours a day. However, if water heaters only provide regulation from 6:00 to 24:00, approximately 20000 will be needed. Because the control algorithm has considered the thermal setting of the water heater, customer comfort is maintained. Therefore, the aggregated regulation service provided by water heater loads can become a major source of revenue for load-serving entities when the smart grid enables the direct load control. © 2011 IEEE.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2011

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January, 2011 are reviewed. Copyright © 2011 John Wiley & Sons, Ltd.


Ogura T.,Japan National Institute of Advanced Industrial Science and Technology
PLoS ONE | Year: 2011

Recently, we developed a soft X-ray microscope called the scanning-electron generation X-ray microscope (SGXM), which consists of a simple X-ray detection system that detects X-rays emitted from the interaction between a scanning electron beam (EB) and the thin film of the sample mount. We present herein a three-dimensional (3D) X-ray detection system that is based on the SGXM technology and designed for studying atmospheric biological samples. This 3D X-ray detection system contains a linear X-ray photodiode (PD) array. The specimens are placed under a CuZn-coated Si3N4 thin film, which is attached to an atmospheric sample holder. Multiple tilt X-ray images of the samples are detected simultaneously by the linear array of X-ray PDs, and the 3D structure is calculated by a new 3D reconstruction method that uses a simulated-annealing algorithm. The resulting 3D models clearly reveal the inner structure of the bacterium. In addition, the proposed method can easily be used for diverse samples in a broad range of scientific fields. © 2011 Toshihiko Ogura.


Hatano H.,Japan National Institute of Advanced Industrial Science and Technology
Chemical Engineering Science | Year: 2010

Low temperature pyrolysis and gasification has been investigated based on the chemical looping combustion (CLC), where insufficient amount of lattice oxygen was reacted with hydrocarbons. Metal oxides such as nickel oxide, iron oxide and titanium oxide were used as lattice oxygen source and were coated on silica gel or porous aluminum. Single column reactor was used for experiments and 36.1 mmol of polyethylene was dropped to the column whose temperature was ranged from 693 to 1073 K. For the pyrolysis, hydrogen yield was 100% of polyethylene contained hydrogen, while methane, CO and CO2 were minor products and almost half of the supplied carbon was deposited on the particle surface. On the other hand, for the steam gasification, 2-3 mol of the hydrogen was generated from 1 mol of carbon and almost no carbon deposition was observed. It is found that no wax and heavy tar was observed in the exhaust. Therefore, the lattice oxygen was able to be applied to the low temperature gasification of hydrocarbons. © 2009 Elsevier Ltd. All rights reserved.


Maekawa T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Chemical and Engineering Data | Year: 2010

Equilibrium conditions of clathrate hydrates formed from propane and aqueous solutions of propanone and sodium chloride were experimentally measured at a temperature range of (264.7 to 276.9) K and pressures up to 0.514 MPa using an isochoric method. The equilibrium temperatures of the clathrate hydrates decrease as the propanone concentrations increase, indicating that propanone has an inhibiting effect on propane hydrate formation. © 2010 American Chemical Society.


Ogura T.,Japan National Institute of Advanced Industrial Science and Technology
Nanotechnology | Year: 2010

Analytical methods with nanometre-scale resolution are indispensable in various scientific fields, including biology, chemistry and nanotechnology. One suitable tool, the soft x-ray microscope, provides high spatial resolution of unstained specimens. Recently, we developed an x-ray microscope called a scanning electron generation x-ray microscope (SGXM). This system had attached additional x-ray detection equipment to the scanning electron microscope (SEM). Here, we describe a new sample stage containing an improved x-ray emission film that enables the acquisition of high-resolution x-ray images of unstained samples. The method proposed in this study, which uses the new SGXM, enables us to acquire x-ray images by using an intact, conventional SEM without additional x-ray detection equipment. Moreover, experiments demonstrate that the new SGXM achieves a spatial resolution of 11nm. Therefore, our system can be easily used for acquiring high-resolution images of a variety of samples across a broad range of scientific fields. © 2010 IOP Publishing Ltd.


Kase Y.,Japan National Institute of Advanced Industrial Science and Technology
Bulletin of the Seismological Society of America | Year: 2010

Most large earthquakes occur on several faults, and accordingly it is important to the prediction of earthquake size to know whether several adjacent faults rupture simultaneously and how slips are distributed on the simultaneously ruptured faults. In this article, I investigate slip-length scaling law, simulating spontaneous rupture processes on multisegmented strike-slip faults in a 3D half-space. Because of fault interaction, the amount of slip caused by simultaneous ruptures on two or more segments is larger than that of a rupture on a single segment. The fault inter-action decreases with the distance between segments, thus the amount of slip attains a constant value when more than two segments rupture. The decrease of fault interaction also causes the small rate of slip increase for simultaneous ruptures on long segments. The numerical results physically support the empirical scaling law, which is characterized by a strong increase of slip with length and a tendency for slip to saturate for very long faults.


Kimura T.,Japan National Institute of Advanced Industrial Science and Technology
APL Materials | Year: 2014

Porous titania films with different macrostructures were prepared with precise control of condensation degree and density of the oxide frameworks in the presence of spherical aggregates of polystyrene-block-poly(oxyethylene) (PS-b-PEO) diblock copolymer. Following detailed explanation of the formation mechanisms of three (reticular, spherical, and large spherical) macrostructures by the colloidal PS-b-PEO templating, structural variation of the titania frameworks during calcination were investigated by X-ray diffraction and X-ray photoelectron spectroscopy. Then, photocatalytic performance of the macroporous titania films was evaluated through simple degradation experiments of methylene blue under an UV irradiation. Consequently, absolute surface area of the film and crystallinity of the titania frameworks were important for understanding the photocatalytic performance, but the catalytic performance can be improved further by the macrostructural design that controls diffusivity of the targeted molecules inside the film and their accessibility to active sites. © 2014 Author(s).


Yoshida M.,Japan National Institute of Advanced Industrial Science and Technology
Chemical Record | Year: 2010

In this article, novel gel-forming materials based on oligomeric and polymeric electrolytes for not only water but also organic solvents, including ionic liquids, are highlighted especially the synthesis, derivatization, and physical property. The oligoelectrolytes with cationic pyridinium backbone can be very easily prepared by the intermolecular quaternization of the ampholytic monomer. The ionene polymers with N,N'-(p-phenylene)dibenzamide linkages as polyelectrolyte were also straightforwardly synthesized in high yields by the copolymerization of 1,4-bis[4-(chloromethyl)benzamide]benzene and commercially available α, ω-ditertiary amines. The oligo-and polyelectrolytes provided physical hydrogels under ca. 1-5 wt% of the concentrations after heating and cooling at room temperature without any other additives. These cationic gelators have characteristic properties, such as acid resistance, a self-healing nature after mechanical collapse, and a dispersant ability for single-walled carbon nanotubes, which have been rarely attainable for conventional physical gelators. © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.


Ohashi H.,Japan National Institute of Advanced Industrial Science and Technology
Proceedings of the International Symposium on Power Semiconductor Devices and ICs | Year: 2012

It is confirmed that more electric society is right direction toward sustainable growth achievement. Electronics including power electronics which enables efficient energy usage is important key technology for the society. Nega-watt cost concept, as an index of development, is proposed to promote efficiency improvement and prevalence of the next generation power electronics (PEs). Improvement of power density and watt cost are key factors for nega-watt cost down. Seed technologies are discussed from system integration point of view. In terms of manufacturability, the importance of high quality wafer supply is mentioned. Finally strategies of Japan for the PEs are referred. © 2012 IEEE.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2012

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since July 2011 are reviewed. Copyright © 2011 John Wiley & Sons, Ltd. Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since July 2011 are reviewed. Copyright © 2011 John Wiley & Sons, Ltd.


Maekawa T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Chemical and Engineering Data | Year: 2016

Equilibrium conditions of xenon hydrates in the presence of aqueous solutions of alcohols, glycols, and glycerol were experimentally measured in a pressure range up to 1 MPa using an isochoric method. Adding the chemicals to water lowered the equilibrium temperature of xenon hydrate, indicating that the chemicals acts as the hydrate inhibitors. On a mass basis, the inhibiting effect on xenon hydrate formation decreased in the following order: methanol > ethanol > ethylene glycol > glycerol ≈ diethylene glycol > triethylene glycol. The order is the same as those for other hydrates of ethane, propane, and carbon dioxide. © 2015 American Chemical Society.


Niki E.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Berry Research | Year: 2011

The role of antioxidants in the maintenance of health and prevention of disorders and diseases has received much attention. Above all, the action and effects of natural antioxidants contained in foods, fruits, spices, beverages and dietary supplements have been the subjects of extensive studies. The capacity of antioxidants has been assessed by various methods, but they often give inconsistent and conflicting results. Animal and human studies do not always support the beneficial effects of antioxidants and the methods for assessment of antioxidant effect are critically needed. In the present article, the methods of assessment of antioxidant capacity are critically reviewed. © 2011 - IOS Press and the authors. All rights reserved.


Hibino T.,Japan National Institute of Advanced Industrial Science and Technology
Applied Clay Science | Year: 2010

Novel nanocomposite hydrogels were prepared with agarose, which is an uncharged biopolymer, and delaminated lactate-containing layered double hydroxide (lactate-LDH). An aqueous colloidal dispersion of delaminated lactate-LDH was added to a hot aqueous solution of agarose at various agarose/LDH ratios. The mixtures were gelled by cooling to room temperature. The gels were frozen in liquid nitrogen, freeze dried, and observed with a field emission scanning electron microscope. Nanoscale dispersion of the lactate-LDH nanoplates in the polymer network was confirmed. © 2010 Elsevier B.V.


Imai H.,Japan National Institute of Advanced Industrial Science and Technology
Measurement: Journal of the International Measurement Confederation | Year: 2013

In our daily life, numerical evaluation of a quantity is normally required not only for scientific decision but also for judgment of products. Under the Metre Convention, ideal system of the International System of units (SI) is globally recognized and utilized in many fields of science and technology [1]. Some documented standards such as International Vocabulary of Metrology (VIM) [2], and Guide to the expression of Uncertainty in Measurement (GUM) [3] are edited and published by the Joint Committee for Guides in Metrology (JCGM) and commonly introduced in the fields of metrology, science and conformity assessment in connection with ISO/IEC 17025. This paper describes the recent situation in measurement science, and how to obtain a reliable measurement result using the expression of metrological traceability together with measurement uncertainty. In the paper, a response to Prof. Ludwik Finkelstein's message for 'challenges and problems to future advancement in measurement science' is also reported. © 2013 Elsevier Ltd.


De Wolf S.,Ecole Polytechnique Federale de Lausanne | Ballif C.,Ecole Polytechnique Federale de Lausanne | Kondo M.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

Low-temperature annealing of hydrogenated amorphous silicon (a-Si:H) is investigated. An identical energy barrier is found for the reduction of deep defects in the bulk of a-Si:H films and at the interface such layers form with crystalline Si (c-Si) surfaces. This finding gives direct physical evidence that the defects determining a-Si:H/c-Si interface recombination are silicon dangling bonds and that also kinetically this interface has no unique features compared to the a-Si:H bulk. © 2012 American Physical Society.


Ogawa Y.,Japan National Institute of Advanced Industrial Science and Technology
Science and Technology of Welding and Joining | Year: 2011

A high speed imaging technique is an attractive tool to elucidate arc welding phenomena. In this study, applications of this technique have been reviewed to aid understanding of arc welding phenomena. Laser illumination with narrow band interference filter is useful to reduce output power of external light. A monochromatic imaging technique is useful for precise measurements. Using narrow band interference filters in infrared wavelength is convenient to evaluate an approximate overview of arc process. It is possible to evaluate surface temperatures of electrode and molten pool. Spectrum distributions of welding and their time series acquisitions are easily obtained using a high speed camera with a special prism attached on the camera. Simultaneous use of many high speed cameras with different wavelength sensitivities aid accurate understanding of physical phenomena during welding. While collection of large datasets from high speed observations leads to data manipulation problems, suitable image analysis techniques allow important characteristics to be extracted in a simple, compact form. © 2011 Institute of Materials, Minerals and Mining.


Ito H.,Japan National Institute of Advanced Industrial Science and Technology
International Journal of Hydrogen Energy | Year: 2016

In May 2009, residential micro-combined heat and power systems (micro-CHPs) were launched onto the market under the standard name of "ENEFARM" in Japan. Operation of the latest type released in 2015 was simulated (using commercial software) with the averaged load data from an actual demonstration project in Japan. Simulation results were then used in economic and environmental analysis. Economic analysis revealed that the target cost of a micro-CHP including the back-up boiler is about $6200 under current Japanese grid prices. This target is a capital cost to achieve the economic feasibility within ten years, and is approximately half of the current actual cost. According to environmental analysis, carbon dioxide emission (CDE) reduction with a micro-CHP is reliable even when the CDE factor of the grid electricity is as low as 200 g-CO2/kWh. Under the current CDE factor in Japan, the application of a micro-CHP would reduce the CDE of the respective home by 19%. © 2016 Hydrogen Energy Publications LLC.


Kitazawa M.,Japan National Institute of Advanced Industrial Science and Technology
Current Diabetes Reports | Year: 2013

Homeostatic systems have adapted to respond to the diurnal light/dark cycle. Numerous physiological pathways, including metabolism, are coordinated by this 24-h cycle. Animals with mutations in clock genes show abnormal glucose and lipid metabolism, indicating a critical relationship between the circadian clock and metabolism. Energy homeostasis is achieved through circadian regulation of the expression and activity of several key metabolic enzymes. Temporal organization of tissue metabolism is coordinated by reciprocal cross-talk between the core clock mechanism and key metabolic enzymes and transcriptional activators. The aim of this review is to define the role of the circadian clock in the regulation of insulin sensitivity by describing the interconnection between the circadian clock and metabolic pathways. © 2012 Springer Science+Business Media New York.


Matsumura Y.,Japan National Institute of Advanced Industrial Science and Technology | Ishibe H.,Nippon Seisen Co.
Journal of Molecular Catalysis A: Chemical | Year: 2011

Methanol steam reforming to hydrogen and carbon dioxide is catalyzed over Cu/ZnO prepared by a coprecipitation method. The addition of zirconium ions to the starting material of the catalyst results in improvement of the activity and reduction in the particle sizes of copper and zinc oxide. However, the surface activity of copper on Cu/ZnO/ZrO 2 is similar to that for Cu/ZnO. It is suggested that the activity depends mainly on the interaction between Cu and ZnO particles and the presence of zirconium oxide does not directly affect the activity. Steep deactivation occurs over Cu/ZnO in the reaction at 400 °C, but the presence of ZrO 2 particles hampers the aggregation and/or sintering of Cu and ZnO particles and mitigates the deactivation. © 2011 Elsevier B.V. All rights reserved.


Yanagisawa T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of the Physical Society of Japan | Year: 2012

Recently, a series of noncentrosymmetric superconductors has been a subject of considerable interest since the discovery of superconductivity in CePt3Si. In noncentrosymmetric materials, the degeneracy of bands is lifted in the presence of spin-orbit coupling. This will bring about new effects in the Kondo effect since the band degeneracy plays an important role in the scattering of electrons by localized spins. We investigate the single-impurity Kondo problem in the presence of spin-orbit coupling. We examine the effect of spin-orbit coupling on the scattering of conduction electrons, by using the Green's function method, for the s-d Hamiltonian, with employing a decoupling procedure. As a result, we obtain a closed system of equations of Green's functions, from which we can calculate physical quantities. The Kondo temperature TK is estimated from a singularity of Green's functions. We show that TK is reduced as the spin-orbit coupling constant α is increased. When 2αkF is comparable to or greater than k BT K(α = 0), T K shows an abrupt decrease as a result of the band splitting. This suggests a Kondo collapse accompanied with a sharp decrease of T K. The log T-dependence of the resistivity will be concealed by the spin-orbit interaction. © 2012 The Physical Society of Japan.


Nakamura H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Physical Chemistry C | Year: 2010

The idea of doping and chemical substitutions for bridge molecules is one of promising techniques to control the transport properties and engineering of molecular devices. In the present article, we extend this concept and propose the use of internal substitutions to detect the mechanism of ballistic and inelastic transport through molecular junctions. By performing first-principles transport calculations for several internally substituted systems, we show systematic pathway analysis of tunneling electrons and vibronic states as well as electron-phonon couplings on bridge molecules. The correlation of inelastic electron tunneling spectroscopy (IETS) and Raman spectroscopy is also discussed. © 2010 American Chemical Society.


Inagaki M.,Hokkaido University | Konno H.,Hokkaido University | Tanaike O.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Power Sources | Year: 2010

The carbon materials used for electrochemical capacitors were reviewed and discussed the contribution of the surfaces owing to micropores and other larger pores to the capacitance and rate performance of the electric double-layer capacitors. The necessity to have an internationally accepted specification for the measurement of capacitor performance was emphasized. © 2010 Elsevier B.V. All rights reserved.


Okumura H.,Japan National Institute of Advanced Industrial Science and Technology
MRS Bulletin | Year: 2015

Energy savings and efficient usage of electric power are some of the most urgent issues for future sustainable development of human society. Power electronics is recognized as a key technology in this regard, and the innovation of power electronics is increasingly required. The important role of power electronics innovations in the future human society and a technology roadmap of power electronics utilizing wide bandgap semiconductors, which are typically represented by silicon carbide, are presented. This roadmap consists of several different domains in technology, from the materials side to the applications side. On this roadmap, three generations are defined as technological streams. Based on this roadmap, recent progress in silicon carbide power electronics is reviewed, and future prospects are discussed. © 2015 Materials Research Society.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems
Progress in Photovoltaics: Research and Applications | Year: 2010

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January 2010 are reviewed. Copyright © 2010 John Wiley & Sons, Ltd.


Hilczer M.,Technical University of Lodz | Tachiya M.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Physical Chemistry C | Year: 2010

Geminate and bulk charge recombination in organic solar cells are extensively studied because they are major loss processes for cell efficiency. It was recently found that the observed bulk charge recombination rate constants in organic solar cells are more than 3 orders of magnitude smaller than those predicted from Langevin theory. In order to resolve this discrepancy, we develop a unified theory of geminate and bulk charge recombination by taking into account that recombination between an electron and a hole occurs at a nonzero separation with a finite intrinsic recombination rate. On the basis of this theory we successfully explain the observed results on bulk recombination rate constants. We also analyze how recombination between electrons and holes in geminate and bulk recombination phases is affected by various physical parameters, such as the intrinsic recombination rate, the diffusion coefficients of electrons and holes, the Onsager radius, and an external electric field, and show how they are optimized to suppress recombination loss. © 2010 American Chemical Society.


Chen Y.-Z.,Suzhou University of Science and Technology | Xu Q.,Japan National Institute of Advanced Industrial Science and Technology | Yu S.-H.,Suzhou University of Science and Technology | Jiang H.-L.,Suzhou University of Science and Technology
Small | Year: 2014

Noble metal nanoparticles (NP) have been the subject of intense research due to the unique physiochemical properties compared to their bulk counterparts and broad applications in energy conversion and storage, cancer therapy, and sensing, especially for catalysis. The performance of the core-shell nanocatalyst was significantly affected by the core NPs although the catalytic reaction takes place on the shell. In addition, metal NPs with small sizes are desired with preferable catalytic activities, while one particular concern is that small NPs have high surface energies and readily aggregate to larger NPs with deteriorative performance. Therefore, much endeavors have been devoted to developing effective approaches to stabilize NPs. Taking advantage of the unique reducing agent of AB, the relative reduction potentials of the metal ions as well as MOF confinement, the rational synthetic strategy employed here may be general and open up a new avenue for preparing surfactant-free bimetallic core-shell NPs with very small sizes.


Tasaki Y.,Japan National Institute of Advanced Industrial Science and Technology | Okada T.,Tokyo Institute of Technology
Journal of the American Chemical Society | Year: 2012

Ice chromatography measurements have revealed anomalous enhancements of crown ether complexation in a liquid phase coexistent with ice. The 4 orders of magnitude enhancement was confirmed for the complexation of dibenzo-24-crown-8 in sub-μm-sized liquid inclusions formed in ice doped with <1 mM NaCl or KCl. This enhancement became less pronounced with increasing dopant concentration. © 2012 American Chemical Society.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems
Progress in Photovoltaics: Research and Applications | Year: 2010

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2009 are reviewed. Copyright © 2010 John Wiley & Sons, Ltd.


Masuda Y.,Japan National Institute of Advanced Industrial Science and Technology
Progress in Crystal Growth and Characterization of Materials | Year: 2012

Nucleation and crystal growth of tin oxide were realized in aqueous solutions. Nano-sheet structures grew in the solutions containing SnF 2 at 90 °C to develop in-plane size and thickness gradually. Their color, size, morphology, crystal structure and N 2 adsorption property varied with progress of crystal growth. Color of powder changed from white to light yellow, light blown to light green particles with growth. XRD analyses clarified that single phase of SnO 2 was synthesized in the aqueous solutions without high temperature annealing. It is an advantage to conventional ceramic firing process. Growth curves of crystallite size were consistent with morphological observations using Field Emission Scanning Electron Microscopy FE-SEM. Development of sheet structure was caused by crystal growth of SnO 2. Large crystallite size perpendicular to (200) planes indicated that growth along c-axis was suppressed compared to a-axis. Anisotropic crystal growth resulted anisotropic shape of nano-sheets. Chemical composition of fluorine-doped SnO 2 nano-sheets was estimated to Sn: F = 1: 0.06-0.12. BET surface area increased with crystal growth and reached to 85 m 2/g. It gradually decreased with synthesis period. Growth of sheet structure along in-plane direction related to increase of surface area. Further growth in thickness increased volume of the sheets to cause decrease of surface area per weight. N 2 adsorption property strongly related to crystal growth and shape change of the nano-structures. The system has the advantage of morphology controllability of tin oxide nano-structure and low environmental load. © 2012 Elsevier Ltd. All rights reserved.


Kobayashi Y.,Japan National Institute of Advanced Industrial Science and Technology
Defect and Diffusion Forum | Year: 2012

Positron chemistry refers to chemical processes of high-energy positrons injected into molecular substances, the most interesting of which is the formation of positronium (Ps), the hydrogen-like bound state between a positron and an electron. Ps is formed predominantly by fast intra-track radiation chemical processes. In polymers it tends to be localized in intra/inter- molecular open space in the sparsely packed amorphous structure. Whilst short-lived singlet para-positronium (p-Ps) undergoes self-annihilation, the positron in long-lived triplet ortho-positronium (o-Ps) annihilates with one of the spin opposite electrons bound in the surrounding polymer molecules. This process is called pick-off annihilation. The pick-off annihilation lifetime reflects the polymer chain packing through the size of the volume, where Ps is localized. Positrons are used to probe the amorphous structure of various polymeric systems. In this article, basic concepts and experimental techniques of positron chemistry in polymers as well as applications to the characterization of functional polymeric materials are overviewed. © (2012) Trans Tech Publications, Switzerland.


Arimoto H.,Japan National Institute of Advanced Industrial Science and Technology | Egawa M.,Shiseido Research Center
Skin Research and Technology | Year: 2015

Background/purpose: We investigate the measurement sensitivity for the water content distribution in Near-infrared (NIR) imaging ranging up to 2 μm. Methods: To evaluate the sensitivity, our attention is focused to the light penetration depth in the skin tissue because the thickness of a layer where the water content can be varied is very thin and deep light penetration decreases the signal variation. The light penetration depths in the wavelengths of 1300, 1450, and 1920 nm are calculated theoretically based on the Monte Carlo light transport simulation. Results: It is clarified that the wavelength of 1920 nm gives the smallest penetration depth. A NIR imaging experiment is demonstrated to verify the difference of imaging sensitivity. The experiment result shows that the NIR image taken at 1920 nm gives the most sensitive measurement of the water content distribution in skin. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.


Ogura T.,Japan National Institute of Advanced Industrial Science and Technology
Measurement Science and Technology | Year: 2012

Imaging at nanometre-scale resolution is indispensable for many scientific fields, such as biology, physics, chemistry, materials science and nanotechnology. Electron microscopy is an important technique to produce high-resolution images of biological samples. Inner structure inspection of cell samples of a few micrometre thickness is enabled using a high-voltage electron beam (EB) of around 1000kV. However, large and complex equipment is required for such systems. Therefore, a more convenient and simple measurement system is desired. Here, we show clear observations of the inner structure of unstained atmospheric cells using a low-voltage EB of less than 10kV. Experiments suggest that whole cell imaging by a low-voltage EB is enabled by the transmission electrons (TEs), and TEs are of very low energy of less than 20eV. Therefore, the damage to the biological samples is very low. Our microscope system can easily be applied for diverse samples, such as cells, bacteria, viruses and other organic samples. © 2012 IOP Publishing Ltd.


Yamada N.,Panasonic | Yamada N.,Japan National Institute of Advanced Industrial Science and Technology
Physica Status Solidi (B) Basic Research | Year: 2012

Discovery of the GeSbTe phase-change alloy in particular along the GeTe-Sb 2Te 3 tie-line took place in the mid-1980s. The amorphous alloys showed ideal properties, for example, high thermal stability at r.t. and laser-induced rapid crystallization with large optical changes. Thereafter, GeSbTe was successively applied to various optical disks such as DVDs and BDs. Through DSC and XRD analyses, the appearance of the metastable phase having a NaCl-type structure was observed over a wide compositional region. This was the "key" to realizing the ideal phase-change properties. During this year, the role of the constituent elements of Ge and Sb became clear by RMC modeling using AXS data at SPring-8, where the "nucleation dominant crystallization process" was well explained. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Asai Y.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

A small zero-bias anomaly (ZBA) in inelastic tunneling spectroscopy (IETS) through nonmagnetic quantum wires has been suggested experimentally at low temperatures. Here, the mechanism is discussed theoretically with special attention paid to contributions from low energy phonons. Our theoretical calculations, using an electron-phonon coupling model, predict the ZBA. While experimental information is still limited, our theoretical result agrees with existing experiments. The theory provides useful information, characterizing the ZBA in a nonmagnetic junction. © 2012 American Physical Society.


Zayets V.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

The spin and charge transport in materials with spin-dependent conductivity has been studied. It has been shown that there is a charge accumulation along spin diffusion in a ferromagnetic metal, which causes a shortening of the spin diffusion length. It has been shown that there is a substantial interaction between the drift and diffusion currents in semiconductors. The effects of gain/damping of a spin current by a charge current and the existence of a threshold spin current in a semiconductor have been described. Because of the substantial magnitude, these new spintronics effects might be used for new designs of efficient spintronic devices. The influence of a spin drain on spin transport has been studied. © 2012 American Physical Society.


Morimoto Y.,University of Occupational and Environmental Health Japan | Horie M.,University of Occupational and Environmental Health Japan | Kobayashi N.,Japan National Institute of Health Sciences | Shinohara N.,Japan National Institute of Advanced Industrial Science and Technology | Shimada M.,Hiroshima University
Accounts of Chemical Research | Year: 2013

Although the demand for nanomaterials has grown, researchers have not conclusively determined the effects of nanomaterials on the human body. To understand the effects of nanomaterials on occupational health, we need to estimate the respiratory toxicity of nanomaterials through inhalation studies, intratracheal instillation studies, and pharyngeal aspiration studies. The discrepancies observed among these studies tend to result from differences in the physiochemical properties of nanomaterials, such as aggregation and dispersion. Therefore, in all toxicity studies, identification of the physicochemical properties of nanomaterials is essential.This Account reviews the inhalation toxicity of manufactured nanomaterials and compares them with inhalation and intratracheal instillation studies of well-characterized fullerene and carbon nanotubes. In many reports, pulmonary inflammation and injury served as pulmonary endpoints for the inhalation toxicity. To assess pulmonary inflammation, we examined neutrophil and macrophage infiltration in the alveolar and/or interstitial space, and the expression of the neutrophil and/or monocyte chemokines. We also reported the release of lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) in the bronchoalveolar lavage fluid (BALF), the expression of oxidative stress-related genes characteristic of lung injury, and the presence of granulomatous lesion and pulmonary fibrosis.In the inhalation and intratracheal instillation studies of well-characterized fullerenes, exposure to fullerene did not induce pulmonary inflammation or transient inflammation. By contrast, in an inhalation study, a high concentration of multiwall carbon nanotubes (MWCNTs) and single-wall carbon nanotubes (SWCNTs) induced neutrophil inflammation or granulomatous formations in the lung, and intratracheal instillation of MWCNTs and SWCNTs induced persistent inflammation in the lung.Among the physicochemical properties of carbon nanotubes, the increased surface area is associated with inflammatory activity as measured by the increase in the rate of neutrophils measured in bronchoalveolar lavage fluid. Metal impurities such as iron and nickel enhanced the pulmonary toxicity of carbon nanotubes, and SWCNTs that included an amorphous carbon induced multifocal granulomas in the lung while purer SWCNTs did not. The aggregation state also affects pulmonary response: Exposure to well-dispersed carbon nanotubes led to the thickening of the alveolar wall and fewer granulomatous lesions in the lung, while agglomerated carbon nanotubes produced granulomatous inflammation.The values of the acceptable exposure concentration in some countries were based on the data of subacute and subchronic inhalation and intratracheal instillation studies of well-characterized fullerene and carbon nanotubes. In Japan, the acceptable exposure concentration of fullerene is 0.39 mg/m3. In Europe, the proposal concentration is 44.4 μg/m3 for acute toxicity and 0.27 μg/m3 for chronic toxicity. The proposal acceptable exposure concentrations of carbon nanotubes are 0.03, 0.05, and 0.007 mg/m3 in Japan, Europe, and the United States, respectively. © 2012 American Chemical Society.


Asai H.,Japan National Institute of Advanced Industrial Science and Technology | Tachiki M.,University of Tsukuba | Kadowaki K.,University of Tsukuba
Applied Physics Letters | Year: 2012

We propose a THz patch antenna, in which THz ac current is fed by intrinsic Josephson junctions (IJJs). The radiation power of the antenna for three different feed positions is calculated using the finite-difference time-domain method. We predict that the antenna will radiate sub-milliwatt terahertz waves with high radiation efficiency of over 20. The maximum radiation power will depend on the position of the feed. We also show that the radiation characteristics of the antenna are described well by the equivalent inductance-capacitance-resistance circuit model. © 2012 American Institute of Physics.


Higo N.,Japan National Institute of Advanced Industrial Science and Technology
Neuroscience Research | Year: 2014

Neuromotor systems have the capacity for functional recovery following damage to the central nervous system. This recovery can be enhanced by rehabilitative training. Animal studies in which artificial damage is induced in a specific region of the brain or spinal cord of rodents or monkeys have contributed to our understanding of the effects of rehabilitative training. In this article, I provide an overview of recent studies in which experimental animals were used to investigate the effects of rehabilitative training on motor recovery and brain plasticity. A study from my group in the macaque monkey reported the effects of hand motor training on motor recovery after lesioning of the primary motor cortex (M1) or the corticospinal tract at the cervical level. In monkeys that had undergone extensive post-lesion training, manual dexterity recovered to previous levels. Rehabilitative training was more effective in promoting recovery of manual dexterity when initiated immediately after the corticospinal tract lesion rather than 1 month later. Both functional brain imaging and gene expression analyses suggest that functional and structural changes may occur in undamaged motor areas during recovery of hand function after M1 or corticospinal tract lesions. © 2013 The Author.


Murakami T.,Japan National Institute of Advanced Industrial Science and Technology
Carbohydrate Research | Year: 2013

All four stereoisomers of 5-formyl-4-hydroxymethyl-1,3-oxazolidin-2-ones (FHOs) were conveniently prepared from d-glucosamine by base-catalyzed epimerizations. 2-N,3-O-Carbonyl-d-glucosamine (7) was successively treated with NaBH4 and NaIO4 to give (4S,5R)-FHO 18, which was epimerized with DBU in DMF to give (4S,5S)-FHO 20. The glucosamine derivative 7 was epimerized to 2-N,3-O-carbonyl-d-mannosamine 23, from which (4R,5R)- and (4R,5S)-FHO derivatives (27 and 31) were prepared. The NMR measurements revealed that the 4,5-cis-4(or 5)-formyl-5(or 4)-hydroxymethyl-oxazolidinone derivatives form five-membered lactol ring, whereas the 4,5-trans-disubstituted derivatives form the hydrate or methanol adduct of the open-chain aldehyde, or the symmetrical dimer. © 2013 Elsevier Inc. All rights reserved.


Tatematsu M.,Hokkaido University | Nishikawa F.,Japan National Institute of Advanced Industrial Science and Technology | Seya T.,Hokkaido University | Matsumoto M.,Hokkaido University
Nature Communications | Year: 2013

Endosomal Toll-like receptor 3 (TLR3) serves as a sensor of viral infection and sterile tissue necrosis. Although TLR3 recognizes double-stranded RNA, little is known about structural features of virus- or host-derived RNAs that activate TLR3 in infection/inflammatory states. Here we demonstrate that poliovirus-derived single-stranded RNA segments harbouring stem structures with bulge/internal loops are potent TLR3 agonists. Functional poliovirus-RNAs are resistant to degradation and efficiently induce interferon-α/β and proinflammatory cytokines in human and mouse cells in a TLR3-dependent manner. The N- and C-terminal double-stranded RNA-binding sites of TLR3 are required for poliovirus-RNA-mediated TLR3 activation. Like polyriboinosinic: polyribocytidylic acid, a synthetic double-stranded RNA, these RNAs are internalized into cells via raftlin-mediated endocytosis and colocalized with TLR3. Raftlin-associated RNA uptake machinery and the TLR3 RNA-sensing system appear to recognize an appropriate topology of multiple RNA duplexes in poliovirus-RNAs. Hence, TLR3 is a sensor of extracellular viral/host RNA with stable stem structures derived from infection or inflammation-damaged cells. © 2013 Macmillan Publishers Limited. All rights reserved.


Ikehara T.,Japan National Institute of Advanced Industrial Science and Technology | Tsuchiya T.,Kyoto University
Journal of Microelectromechanical Systems | Year: 2012

The authors used a ramping-amplitude fatigue-test method to perform low-cycle fatigue tests in micrometer-sized single-crystal-silicon specimens using a resonant-type fatigue-test device. Very short delayed fractures from 4 ms to 29 s were observed by controlling the amplitude ramping rates with two self-oscillation electric circuits and different parameters. These lifetimes were converted to corresponding constant-amplitude lifetimes from 10 1 to 10 5 cycles using the relationship derived from a crack-growth analysis. S-N plots of measured lifetimes exhibited the transition of fatigue lives at the high-cycle region with a crack-growth exponent of 18.0, to the static fracture strength of 6.50 GPa at the low-cycle region corresponding to the original crack length of 7.9 nm. The existence of a very rapid fatigue fracture within 1 s was confirmed. From the obtained crack-growth parameters, the evolution of crack length and the effects of humidity were discussed. © 2012 IEEE.


Fukatsu T.,Japan National Institute of Advanced Industrial Science and Technology
Molecular Ecology | Year: 2012

Next-generation sequencing (NGS) technologies are getting cheaper and easier and hence becoming readily accessible for many researchers in biological disciplines including ecology. In this issue of Molecular Ecology, Sudakaran et al. (2012) show how the NGS revolution contributes to our better and more comprehensive understanding of ecological interactions between gut symbiotic microbiota and the host organism. Using the European red firebug Pyrrhocoris apterus as a model system, they demonstrated that the gut microbiota consists of a small number of major bacterial phylotypes plus other minor bacterial associates. The major bacteria are localized in a specific anoxic section of the midgut and quantitatively account for most of the gut microbiota irrespective of host's geographic populations. The specific gut microbiota is established through early nymphal development of the host insect. Interestingly, the host feeding on different food, namely linden seeds, sunflower seeds or wasp larvae, scarcely affected the symbiont composition, suggesting homoeostatic control over the major symbiotic microbiota in the anoxic section of the midgut. Some of the minor components of the gut microbiota, which conventional PCR/cloning/ sequencing approaches would have failed to detect, were convincingly shown to be food-derived. These findings rest on the robust basis of high-throughput sequencing data, and some of them could not be practically obtained by conventional molecular techniques, highlighting the significant impact of NGS approaches on ecological aspects of host-symbiont interactions in a nonmodel organism. © 2012 Blackwell Publishing Ltd.


Pedersen H.,Linkoping University | Leone S.,Linkoping University | Kordina O.,Linkoping University | Henry A.,Linkoping University | And 3 more authors.
Chemical Reviews | Year: 2012

A study was conducted to demonstrate chloride-based chemical vapor deposition (CVD) growth of silicon carbide (SiC) for electronic applications. SiC homoepitaxial growth was done using CVD with silane (SiH 4) as the silicon precursor and light hydrocarbons, including ethylene (C 2H 4) or propane (C 3H 8) as the carbon precursor. Simulation was an invaluable tool along with comparisons between different chlorinated chemistries to obtain a deeper understanding of the chloride-based process and provide more information. A number of approaches were selected to add chlorine to the gas mixture for the growth of SiC epitaxial layers using a chloride-based chemistry.


Hamada H.,Japan National Institute of Advanced Industrial Science and Technology | Haneda M.,Nagoya Institute of Technology
Applied Catalysis A: General | Year: 2012

The selective reduction of NO with hydrogen (H 2-SCR) and CO (CO-SCR) over platinum group metal catalysts in the presence of O 2 is overviewed. In the case of H 2-SCR, Pt and Pd show high activity at low temperatures. The acidity of the support material greatly affects NO reduction activity and selectivity to N 2/N 2O. Although the activity of Ir and Rh for H 2-SCR is low, coexisting SO 2 in the reaction gas considerably promotes NO reduction. The best support for Ir and Rh is SiO 2. Li and Zn additives improve the activity of Ir/SiO 2 and Rh/SiO 2, respectively, by maintaining the active reduced metal state. For CO-SCR, on the other hand, Ir is almost the only active metal species. Coexisting SO 2 is also essential for CO-SCR on Ir/SiO 2 to occur. The role of SO 2 for both H 2-SCR and CO-SCR on Ir/SiO 2 is to keep Ir in the form of the catalytically active Ir metal state. The additions of WO 3 and Nb 2O 5 considerably promote the activity of Ir/SiO 2 for CO-SCR, catalyzing CO-SCR even in the absence of SO 2. Ir metal interacting strongly with W oxide is the active species on WO 3-promoted Ir/SiO 2. Furthermore, the addition of Ba improves the performance of Ir/WO 3/SiO 2 catalyst. © 2012 Elsevier B.V. All rights reserved.


Tsuzuki S.,Japan National Institute of Advanced Industrial Science and Technology
ChemPhysChem | Year: 2012

The development of ionic liquids with low viscosity and high ionic conductivity is important for many applications of ionic liquids, such as their use as electrolytes for electronic devices. The transport properties depend on the motion of ions in ionic liquids. The viscosity becomes low and the ionic conductivity becomes high as the diffusion of ions becomes fast. Therefore the elucidation of the factors controlling the diffusion of ions is needed for developing new ionic liquids. In this Minireview we discuss the factors controlling the diffusion of ions in ionic liquids (size of ion; shape of ion; magnitude of interaction between cation and anion; conformational flexibility; molecular mass of ion; mixture of solute; and the effects of nanostructures in ionic liquids). We emphasize the importance of the use of computational methods (molecular dynamic simulations and quantum mechanical calculations) combined with experimental measurements for elucidating the factors controlling the diffusion of ions in ionic liquids. © 2012 Wiley-VCH Verlag GmbH& Co. KGaA, Weinheim.


Tsuzuki S.,Japan National Institute of Advanced Industrial Science and Technology
Annual Reports on the Progress of Chemistry - Section C | Year: 2012

Recent gas phase measurements and high level ab initio calculations of the CH/π interactions show that the nature of the CH/π interactions is significantly different from conventional hydrogen bonds, although the CH/π interactions were often regarded as the weakest class of hydrogen bonds. A clear correlation between the binding energies of the benzene clusters with alkanes in the gas phase and the polarizabilities of alkanes was reported. The correlation suggests that the dispersion interaction is the major source of the attraction of the CH/π interactions. Ab initio calculations also show that the major source of attraction in the CH/π interactions is the dispersion interaction and the electrostatic contribution is small. The nature of the "typical CH/π interactions is close to that of van der Waals interactions, if some exceptional "activated" CH/π interactions of highly acidic C-H bonds (C-H bonds of acetylene and chloroform) are excluded. Conventional hydrogen bonds are sufficiently strong and directional due to the large contribution of the highly orientation dependent electrostatic interactions to the attraction. The hydrogen bond is important in controlling structures of molecular assemblies, since the hydrogen bond is sufficiently strong and directional. On the other hand the "typical" CH/π interactions are weak and their directionality is very weak. Although the "typical" CH/π interactions are often regarded as important interactions in controlling the structures of molecular assemblies as in the cases of conventional hydrogen bonds, the importance of the "typical" CH/π interactions is questionable. © 2012 The Royal Society of Chemistry.


Harris K.R.,University of New South Wales | Kanakubo M.,Japan National Institute of Advanced Industrial Science and Technology
Faraday Discussions | Year: 2012

High pressure measurements have been made of viscosities, ion self-diffusion coefficients and electrical conductivities of ionic liquids, mainly of imidazolium salts. We review how these properties have been analysed in terms of the empirical Stokes-Einstein, Walden and Nernst-Einstein equations, and examine trends revealed by the phenomenological approach of velocity correlation coefficients and the more general theory of density scaling. Finally we examine the possibility of dynamic crossover in the transport properties of ionic liquids. © 2012 The Royal Society of Chemistry.


Jansen R.,Japan National Institute of Advanced Industrial Science and Technology
Nature Materials | Year: 2012

Worldwide efforts are underway to integrate semiconductors and magnetic materials, aiming to create a revolutionary and energy-efficient information technology in which digital data are encoded in the spin of electrons. Implementing spin functionality in silicon, the mainstream semiconductor, is vital to establish a spin-based electronics with potential to change information technology beyond imagination. Can silicon spintronics live up to the expectation? Remarkable advances in the creation and control of spin polarization in silicon suggest so. Here, I review the key developments and achievements, and describe the building blocks of silicon spintronics. Unexpected and puzzling results are discussed, and open issues and challenges identified. More surprises lie ahead as silicon spintronics comes of age. © 2012 Macmillan Publishers Limited. All rights reserved.


Shichiri M.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Clinical Biochemistry and Nutrition | Year: 2014

There has been much evidence demonstrating the involvement of oxidative stress in the pathology of neurological disorders. Moreover, the vulnerability of the central nervous system to reactive oxygen species mediated injury is well established since neurons consume large amounts of oxygen, the brain has many areas containing high iron content, and neuronal mitochondria generate large amounts of hydrogen peroxide. Furthermore, neuronal membranes are rich in polyunsaturated fatty acids, which are particularly susceptible to oxidative stress. Recently, the biological roles of products produced by lipid peroxidation have received much attention, not only for their pathological mechanisms associated with neurological disorders, but also for their practical clinical applications as biomarkers. Here, we discuss the production mechanisms of reactive oxygen species in some neurological disorders, including Alzheimer's disease, Down syndrome, Parkinson's disease, and stroke. We also describe lipid peroxidation biomarkers for evaluating oxidative stress. ©2014 JCBN.


Otsuki S.,Japan National Institute of Advanced Industrial Science and Technology
Journal of the Optical Society of America A: Optics and Image Science, and Vision | Year: 2016

This paper presents a theory describing totally incoherent multiple scattering of turbid spherical samples. It is proved that if reciprocity and mirror symmetry hold for single scattering by a particle, they also hold for multiple scattering in spherical samples. Monte Carlo simulations generate a reduced effective scattering Mueller matrix, which virtually satisfies reciprocity and mirror symmetry. The scattering matrix was factorized by using the symmetric decomposition in a predefined form, as well as the Lu-Chipman polar decomposition, approximately into a product of a pure depolarizer and vertically oriented linear retarding diattenuators. The parameters of these components were calculated as a function of the polar angle. While the turbid spherical sample is a pure depolarizer at low polar angles, it obtains more functions of the retarding diattenuator with increasing polar angle. © 2016 Optical Society of America.


Niki E.,Japan National Institute of Advanced Industrial Science and Technology
Biochimica et Biophysica Acta - General Subjects | Year: 2014

Background: Free radical-mediated lipid peroxidation has been implicated in a number of human diseases. Diverse methods have been developed and applied to measure lipid peroxidation products as potential biomarkers to assess oxidative stress status in vivo, discover early indication of disease, diagnose progression of disease, and evaluate the effectiveness of drugs and antioxidants for treatment of disease and maintenance of health, respectively. However, standardized methods are not yet established. Scope of review Characteristics of various lipid peroxidation products as biomarkers are reviewed on the basis of mechanisms and dynamics of their formation and metabolism and also on the methods of measurement, with an emphasis on the advantages and limitations. Major conclusions Lipid hydroxides such as hydroxyoctadecadienoic acids (HODE), hydroxyeicosatetraenoic acids (HETE), and hydroxycholesterols may be recommended as reliable biomarkers. Notably, the four HODEs, 9-cis,trans, 9-trans,trans, 13-cis,trans, and 13-trans,trans-HODE, can be measured separately by LC-MS/MS and the trans,trans-forms are specific marker of free radical mediated lipid peroxidation. Further, isoprostanes and neuroprostanes are useful biomarker of lipid peroxidation. It is important to examine the distribution and temporal change of these biomarkers. General significance Despite the fact that lipid peroxidation products are non-specific biomarkers, they will enable to assess oxidative stress status, disease state, and effects of drugs and antioxidants. This article is part of a Special Issue entitled Current methods to study reactive oxygen species - pros and cons and biophysics of membrane proteins. Guest Editor: Christine Winterbourn. © 2013 Elsevier B.V. All rights reserved.


Ohgushi H.,Ookuma Hospital | Ohgushi H.,Japan National Institute of Advanced Industrial Science and Technology
Expert Opinion on Biological Therapy | Year: 2014

Introduction: In the human body, cells having self-renewal and multi-differentiation capabilities reside in many tissues and are called adult stem cells. In bone marrow tissue, two types of stem cells are well known: hematopoietic stem cells and mesenchymal stem cells (MSCs). Though the number of MSCs in bone marrow tissue is very low, it can be increased by in vitro culture of the marrow, and culture-expanded MSCs are available for various tissue regeneration. Areas covered: The culture-expanded MSCs can further differentiate into osteogenic cells such as bone forming osteoblasts by culturing the MSCs in an osteogenic medium. This paper discusses osteogenically differentiated MSCs derived from the bone marrow of patients. Importantly, the differentiation can be achieved on ceramic surfaces which demonstrate mineralized bone matrix formation as well as appearance of osteogenic cells. The cell/matrix/ceramic constructs could show immediate in vivo bone formation and are available for bone reconstruction surgery. Expert opinion: Currently, MSCs are clinically available for the regeneration of various tissues due to their high proliferation/differentiation capabilities. However, the capabilities are still limited and thus technologies to improve or recover the inherent capabilities of MSCs are needed. © 2014 Informa UK, Ltd.


Niki E.,Japan National Institute of Advanced Industrial Science and Technology
Free Radical Biology and Medicine | Year: 2014

Multiple reactive oxygen/nitrogen species induce oxidative stress. Mammals have evolved with an elaborate defense network against oxidative stress, in which multiple antioxidant compounds and enzymes with different functions exert their respective roles. Radical scavenging is one of the essential roles of antioxidants and vitamin E is the most abundant and important lipophilic radical-scavenging antioxidant in vivo. The kinetic data and physiological molar ratio of vitamin E to substrates show that the peroxyl radicals are the only radicals that vitamin E can scavenge to break chain propagation efficiently and that vitamin E is unable to act as a potent scavenger of hydroxyl, alkoxyl, nitrogen dioxide, and thiyl radicals in vivo. The preventive effect of vitamin E against the oxidation mediated by nonradical oxidants such as hypochlorite, singlet oxygen, ozone, and enzymes may be limited in vivo. The synergistic interaction of vitamin E and vitamin C is effective for enhancing the antioxidant capacity of vitamin E. The in vitro and in vivo evidence of the function of vitamin E as a peroxyl radical-scavenging antioxidant and inhibitor of lipid peroxidation is presented. © 2013 Elsevier Inc.


Tanaka Y.,Japan National Institute of Advanced Industrial Science and Technology
Superconductor Science and Technology | Year: 2015

Multicomponent superconductivity is realized in multiband superconductors when an interband pairing interaction is considerably weaker than the intraband interactions. There is a new quantum phase that originates from the interband phase difference in this superconducting condensate. Firstly, we discuss the applicability of this physical viewpoint for known multiband superconductors. Secondly, topics related to the interband phase difference are treated. Finally, we mention that the Bardeen-Cooper-Schrieffer formalism and the Ginzburg-Landau formalism may not be fully guaranteed when we introduce a fluctuation in the interband phase difference mode. We also address plausible new superconducting electronics using the interband phase difference. © 2015 IOP Publishing Ltd.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2015

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since January 2015 are reviewed. Copyright © 2015 John Wiley & Sons, Ltd.


Takahashi K.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Bioscience and Bioengineering | Year: 2013

Synthetic polymers always have distributions of the degrees of polymerization. Supercritical fluid chromatography (SFC) is almost only one technique to be able to separate pure polymer that has exactly unique degree of polymerization. For typical examples of SFC separation of polymers, four kinds of polymers: polystyrene, poly(ethylene glycol), some nonionic surfactants, and polyprenol are described about the conditions of SFC. Separated pure polymers which have no molecular weight distribution, are called uniform polymer. Uniform polymers are really useful to calibrate or validate various detectors. Here, the applications of calibrating ultraviolet detector, evaporative light scattering detector, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry are summarized. These detectors have strong molecular weight dependence of their sensitivity coefficient, in contrast to the good linearity of sample concentration. © 2013 The Society for Biotechnology, Japan.


Fujiki H.,Japan National Institute of Advanced Industrial Science and Technology
IEEE Transactions on Instrumentation and Measurement | Year: 2013

Thin-film multijunction thermal converters (MJTCs) with a heater fabricated on an AlN chip have been developed for ac-dc current transfer standards. The rated current of the MJTC can be increased due to the good thermal conductivity of the AlN substrate, which acted as a heat sink drawing away heat from the heater. The AlN chip was mounted on a polyimide foil with thermocouples of the MJTC produced separately. In the case of an MJTC with a heater resistance of 5 Ω, which has a bifilar heater pattern to reduce the thermoelectric effects, the nominal current is 200 mA. The observed current level dependence of the ac-dc current transfer differences from 50 to 200 mA for the 5-Ω MJTC was within 1 μV/V at frequency from 1 to 100 kHz. Compared with a conventional thermal converter, the wide range of available input current and small current level dependence of the new MJTCs may reduce uncertainties of ac-dc current transfer standards. © 2013 IEEE.


Niki E.,Kyoto Prefectural University of Medicine | Niki E.,Japan National Institute of Advanced Industrial Science and Technology
Biomedical Journal | Year: 2014

The radical scavenging antioxidants play an essential role in the maintenance of health and prevention of diseases, and a thorough understanding of the action and capacity of antioxidants is critically important. Despite the assumption that antioxidants must exert beneficial effects against oxidative stress, many large-scale randomized controlled trials gave inconsistent and disappointing results on the prevention of chronic diseases. It is now generally accepted that there is no evidence to support the use of non-discriminative antioxidant supplements for prevention of diseases. On the other hand, recent data show that antioxidants may be effective in the prevention and/or treatment of diseases when the right antioxidant is given to the right subject at the right time for the right duration. Now it is accepted that reactive oxygen species (ROS) act as physiologically important signaling messengers as well as deleterious agents. The signaling ROS are produced in a subtly regulated manner, while many deleterious ROS are produced and react randomly. Free radical-mediated lipid peroxidation products which, in contrast to enzymatic oxidation products, are produced by non-specific mechanisms cause oxidative damage, but may also induce adaptive response to enhance the expression of antioxidant enzymes and compounds. This has raised a question if removal of too many ROS by supplementation of antioxidants may upset the cell signaling pathways and actually increase the risk of chronic diseases. However, it is unlikely that antioxidants impair physiologically essential signaling pathways.


Yanagisawa T.,Japan National Institute of Advanced Industrial Science and Technology
New Journal of Physics | Year: 2013

In this study we have computed the pair correlation functions in the two-dimensional Hubbard model using a quantum Monte Carlo method. We employ a new diagonalization algorithm in the quantum Monte Carlo method which is free from the negative sign problem. We show that the d-wave pairing correlation function is indeed enhanced slightly for the positive on-site Coulomb interaction U when doping away from the half-filling. When the system size becomes large, the pair correlation function P d increases for U > 0 compared to the non-interacting case, while P d is suppressed for U > 0 when the system size is small. The enhancement ratio Pd[U]/Pd[U = 0] will give a criterion on the existence of superconductivity. The ratio Pd[U]/Pd[U = 0] increases almost linearly ∝L when the system size L × L is increased. This increase is a good indication of the existence of a superconducting phase in the two-dimensional Hubbard model. There is, however, no enhancement of pair correlation functions in the half-filled case, which indicates the absence of superconductivity without hole doping. © IOP Publishing and Deutsche Physikalische Gesellschaft.


Watanabe K.,Japan National Institute of Advanced Industrial Science and Technology
Proceedings of the Japan Academy Series B: Physical and Biological Sciences | Year: 2010

In animal mitochondria, several codons are non-universal and their meanings differ depending on the species. In addition, the tRNA structures that decipher codons are some-times unusually truncated. These features seem to be related to the shortening of mitochondrial (mt) genomes, which occurred during the evolution of mitochondria. These organelles probably originated from the endosymbiosis of an aerobic eubacterium into an ancestral eukaryote. It is plausible that these events brought about the various characteristic features of animal mt translation systems, such as genetic code variations, unusually truncated tRNA and rRNA structures, unilateral tRNA recognition mechanisms by aminoacyl-tRNA synthetases, elongation factors and ribosomes, and compensation for RNA deficits by enlarged proteins. In this article, we discuss molecular mechanisms for these phenomena. Finally, we describe human mt diseases that are caused by modification defects in mt tRNAs. © 2010 The Japan Academy.


Tateno H.,Japan National Institute of Advanced Industrial Science and Technology
Bioscience, Biotechnology and Biochemistry | Year: 2010

Glycan-binding proteins are categorized into two groups, lectins and sulfated glycosaminoglycan-binding proteins. SUEL-related lectins are members of a superfamily of proteins containing a carbohydrate-recognition domain (CRD), which is structurally similar to sea urchin egg lectin (SUEL). Here I review the structure and function of this family of proteins.


Escande A.,Japan National Institute of Advanced Industrial Science and Technology | Mansard N.,CNRS Laboratory for Analysis and Architecture of Systems | Wieber P.-B.,French Institute for Research in Computer Science and Automation
International Journal of Robotics Research | Year: 2014

Hierarchical least-square optimization is often used in robotics to inverse a direct function when multiple incompatible objectives are involved. Typical examples are inverse kinematics or dynamics. The objectives can be given as equalities to be satisfied (e.g. point-to-point task) or as areas of satisfaction (e.g. the joint range). This paper proposes a complete solution to solve multiple least-square quadratic problems of both equality and inequality constraints ordered into a strict hierarchy. Our method is able to solve a hierarchy of only equalities 10 times faster than the iterative-projection hierarchical solvers and can consider inequalities at any level while running at the typical control frequency on whole-body size problems. This generic solver is used to resolve the redundancy of humanoid robots while generating complex movements in constrained environments. © The Author(s) 2014.


Niki E.,Japan National Institute of Advanced Industrial Science and Technology | Traber M.G.,Oregon State University
Annals of Nutrition and Metabolism | Year: 2012

Vitamin E (α-tocopherol) was discovered nearly 100 years ago because it was required to prevent fetal resorption in pregnant, vitamin E-deficient rats fed lard-containing diets that were easily oxidizable. The human diet contains eight different vitamin E-related molecules synthesized by plants; despite the fact that all of these molecules are peroxyl radical scavengers, the human body prefers α-tocopherol. The biological activity of vitamin E is highly dependent upon regulatory mechanisms that serve to retain α-tocopherol and excrete the non-α-tocopherol forms. This preference is dependent upon the combination of the function of α-tocopherol transfer protein (α-TTP) to enrich the plasma with α-tocopherol and the metabolism of non-α-tocopherols. α-TTP is critical for human health because mutations in this protein lead to severe vitamin E deficiency characterized by neurologic abnormalities, especially ataxia and eventually death if vitamin E is not provided in large quantities to overcome the lack of α-TTP. α-Tocopherol serves as a peroxyl radical scavenger that protects polyunsaturated fatty acids in membranes and lipoproteins. Although specific pathways and specific molecular targets have been sought in a variety of studies, the most likely explanation as to why humans require vitamin E is that it is a fat-soluble antioxidant. Copyright © 2012 S. Karger AG, Basel.


Fujiki H.,Japan National Institute of Advanced Industrial Science and Technology
IEEE Transactions on Instrumentation and Measurement | Year: 2011

A new type of thin-film multijunction thermal converter (MJTC), which can be fabricated using a simple process, has been developed for use as high-frequency ac-dc transfer standards. The design of this MJTC reduces the coupling between a heater structure and thermocouples at high frequencies, and enables its characteristics to be calculable from the shape of the thermal converter (TC). The influence of the electromagnetic coupling between the heater and the thermocouples can be reduced to less than 20 μV/V at 100 MHz by improving the structure of the thermocouples. The nominal input current is increased to 50 mA by sputtering a heater on an aluminum nitride (AlN) substrate featuring good thermal conductivity, enabling direct comparison measurements between TCs with input resistances of 50 Ω and 1 k Ω. The frequency characteristics of our MJTCs are in a good agreement with the calculated results in the frequency range between 1 and 100 MHz. This paper describes the unique structure of the new MJTC and its frequency characteristics in the frequency range of 1-100 MHz. © 2006 IEEE.


Shin W.,Japan National Institute of Advanced Industrial Science and Technology
Analytical and Bioanalytical Chemistry | Year: 2014

In this article, technical developments in breath analysis and its applications in the field of clinical diagnosis and the monitoring of various symptoms, particularly molecular hydrogen in breath, are introduced. First, a brief overview of the current uses of the hydrogen breath test is provided. The principles of the test and how hydrogen can be used as a biomarker for various symptoms, and monitoring microbial metabolism, are introduced. Ten case-study applications of breath hydrogen measurements for which hydrogen exhibits beneficial effects for diagnosis, including the contexts of oxidative stress, gastrointestinal disease, and metabolic disorders, are discussed. The technologies and problems involved in breath hydrogen testing, sampling, pretreatment, and detection in exhaled breath are discussed, and research including current analytical systems and new sensors is focused on in the context of hydrogen detection. © 2014 Springer-Verlag Berlin Heidelberg.


Imamura T.,Japan National Institute of Advanced Industrial Science and Technology | Imamura T.,Tokyo University of Technology
Biological and Pharmaceutical Bulletin | Year: 2014

Despite their name, fibroblast growth factors (FGFs) are multifunctional regulators affecting a wide variety of physiological events. This review summarizes our recent studies on FGFs from mechanistic, physiological and application-oriented viewpoints. These include studies on the importance of βKlotho and glycosaminoglycans for the signaling of hormonal FGFs (FGF21 and FGF19); the physiological role of a paracrine FGF (FGF18) in hair cycle regulation; and the development of a stable, chimeric FGF protein composed of FGF1 and FGF2 domains suitable for radioprotection. © 2014 The Pharmaceutical Society of Japan.


Shigi N.,Japan National Institute of Advanced Industrial Science and Technology
Frontiers in Genetics | Year: 2014

Sulfur is an essential element for a variety of cellular constituents in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, such as the derivatives of 2-thiouridine (s2U), 4-thiouridine (s4U), 2-thiocytidine (s2C), and 2-methylthioadenosine (ms2A). Earlier studies established the functions of these modifications for accurate and efficient translation, including proper recognition of the codons in mRNA or stabilization of tRNA structure. In many cases, the biosynthesis of these sulfur modifications starts with cysteine desulfurases, which catalyze the generation of persulfide (an activated form of sulfur) from cysteine. Many sulfur-carrier proteins are responsible for delivering this activated sulfur to each biosynthesis pathway. Finally, specific "modification enzymes" activate target tRNAs and then incorporate sulfur atoms. Intriguingly, the biosynthesis of 2-thiouridine in all domains of life is functionally and evolutionarily related to the ubiquitin-like post-translational modification system of cellular proteins in eukaryotes. This review summarizes the recent characterization of the biosynthesis of sulfur modifications in tRNA and the novel roles of this modification in cellular functions in various model organisms, with a special emphasis on 2-thiouridine derivatives. Each biosynthesis pathway of sulfur-containing molecules is mutually modulated via sulfur trafficking, and 2-thiouridine and codon usage bias have been proposed to control the translation of specific genes. © 2014 Shigi.


Kimura N.,Japan National Institute of Advanced Industrial Science and Technology
Virulence | Year: 2014

Quorum sensing, a form of cell-cell communication among bacteria, allows bacteria to synchronize their behaviors at the population level in order to control behaviors such as luminescence, biofilm formation, signal turnover, pigment production, antibiotics production, swarming, and virulence. A better understanding of quorum-sensing systems will provide us with greater insight into the complex interaction mechanisms used widely in the Bacteria and even the Archaea domain in the environment. Metagenomics, the use of culture-independent sequencing to study the genomic material of microorganisms, has the potential to provide direct information about the quorum-sensing systems in uncultured bacteria. This article provides an overview of the current knowledge of quorum sensing focused on phylogenetic diversity, and presents examples of studies that have used metagenomic techniques. Future technologies potentially related to quorum-sensing systems are also discussed. © 2014 Landes Bioscience.


Phillips S.,Japan National Institute of Advanced Industrial Science and Technology | Wilson W.H.,University of New South Wales
PLoS Computational Biology | Year: 2011

A complete theory of cognitive architecture (i.e., the basic processes and modes of composition that together constitute cognitive behaviour) must explain the systematicity property-why our cognitive capacities are organized into particular groups of capacities, rather than some other, arbitrary collection. The classical account supposes: (1) syntactically compositional representations; and (2) processes that are sensitive to-compatible with-their structure. Classical compositionality, however, does not explain why these two components must be compatible; they are only compatible by the ad hoc assumption (convention) of employing the same mode of (concatenative) compositionality (e.g., prefix/postfix, where a relation symbol is always prepended/appended to the symbols for the related entities). Architectures employing mixed modes do not support systematicity. Recently, we proposed an alternative explanation without ad hoc assumptions, using category theory. Here, we extend our explanation to domains that are quasi-systematic (e.g., aspects of most languages), where the domain includes some but not all possible combinations of constituents. The central category-theoretic construct is an adjunction involving pullbacks, where the primary focus is on the relationship between processes modelled as functors, rather than the representations. A functor is a structure-preserving map (or construction, for our purposes). An adjunction guarantees that the only pairings of functors are the systematic ones. Thus, (quasi-)systematicity is a necessary consequence of a categorial cognitive architecture whose basic processes are functors that participate in adjunctions. © 2011 Phillips, Wilson.


Ito F.,Japan National Institute of Advanced Industrial Science and Technology
Computational and Theoretical Chemistry | Year: 2013

Stable isomers of trifluoroacetic acid (TFA) tetrahydrates, TFA-(H2O)4, have been explored by using density functional theory calculations. With the structural constraints assuming a polycyclic skeleton and homodromicity of intermolecular hydrogen bonds, structure optimization and vibrational calculations were performed for 34 isomeric structures (31 for neutral and 3 for ion-pair species, respectively) at the B971/6-311++G(3df,3pd) level. We found that the edge-sharing bicyclic "book-type" isomer is at the global minimum and more stable than the monocyclic structure by ca. 266cm-1. We concluded that the observation of the zwitter-ionic structure in Ar matrices should be difficult, since it was predicted to be unstable by ca. 2500cm-1 energetically. © 2013 Elsevier B.V.


Seki T.,Tohoku University | Utsumiya K.,Tohoku University | Nozaki Y.,Keio University | Imamura H.,Japan National Institute of Advanced Industrial Science and Technology | Takanashi K.,Tohoku University
Nature Communications | Year: 2013

Recent rapid progress in spintronic and magnetic storage nanodevices has required nanomagnets to balance competing goals for high coercive field and low switching field. However, a decisive route for highly efficient magnetization switching has not been established yet. Here we propose a novel switching method using a spin wave of magnetic structures twisted in a nanometre scale. We have experimentally demonstrated extremely low field-magnetization switching in a highly coercive FePt by using a spin wave excited in a soft magnetic permalloy (Ni81Fe19), where permalloy is exchange-coupled to FePt through the interface. We can tune the switching field by varying the magnitude and frequency of the radio frequency magnetic field, and a significant decrease in switching field by one order of magnitude is achieved under the optimum conditions. The spin wave-assisted magnetization switching is a promising technique for ultralow-energy magnetization manipulation. © 2013 Macmillan Publishers Limited. All rights reserved.


Hotta M.,Japan National Institute of Advanced Industrial Science and Technology
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan | Year: 2012

Ultrafine-grained non-oxide ceramics were prepared by combining the synthesis technology for fine-grained starting powders and the rapid sintering technology for spark plasma sintering (SPS); the two technologies were combined for obtaining ceramics with improved heat and corrosion resistance and improved mechanical properties. Hollow spherical Ca-α SiAlON powders composed of nanosized particles were synthesized by carbothermal reduction-nitridation of a SiO 2-Al 2O 3-CaCO 3 powder mixture. Using the Ca-α SiAlON powder, dense Ca-α SiAlON nanoceramics and porous Ca-α SiAlON ceramics with excellent mechanical properties and high heat and corrosion resistance were fabricated by the SPS technique. Ultrafine-grained Si 3N 4 and SiC ceramics were prepared from fine-grained Si 3N 4 and SiC powders by SPS. The densification of cubic-BN-dispersed ceramics composites was achieved without the phase transformation of cubic BN to low-hardness hexagonal BN, at a moderate pressure by the SPS technique. © 2012 The Ceramic Society of Japan.


Ito F.,Japan National Institute of Advanced Industrial Science and Technology
Chemical Physics | Year: 2011

Infrared spectra of trifluoroacetic acid (TFA) hydrates CF 3COOH-(H 2O) n have been observed in Ar matrix. A comparison of the spectra with theoretical calculations led us to the assignments of vibrational peaks for TFA-(H 2O) n up to n = 4. The vibrational peaks of the zwitterion cluster, i.e. (CF 3COO -)(H 3O +)(H 2O) m, have been tentatively assigned for the first time. © 2011 Elsevier B.V. All rights reserved.


Taniguchi T.,Japan National Institute of Advanced Industrial Science and Technology
Applied Physics Express | Year: 2015

Common understanding of magnetization switching in microwave-assisted magnetization reversal is that the rotation direction of the microwaves should be the same as the precession direction of the magnetization. In this letter, however, we show that microwaves initially rotating opposite to the magnetization precession destabilize the magnetization at an equilibrium and induce switching more efficiently when the microwave frequency depends on time. This argument is analytically deduced from an energy balance equation. We also establish a model satisfying this condition and confirm magnetization switching solely by microwaves by using numerical simulation. © 2015 The Japan Society of Applied Physics.


Mekaru H.,Japan National Institute of Advanced Industrial Science and Technology
Microsystem Technologies | Year: 2014

Metal nanostructures are used as wire grids for liquid crystal displays and lighting-receiving surface electrodes of solar cells. They are also integrated in emerging devices for chemical and biomedical detection and analyses carried out under various research and development programs. Currently, the mainstream fabrication method of metal nanostructures needs many manufacturing processes including patterning and metallization technologies. Here, our high-temperature nanoimprint technology for glass materials was applied to metals, which led to the development of technology to transfer nanopatterns onto a metal foil using a quartz mold. Although the glass transition temperature does not exist in metal but plastic deformation of metal is possible if the metal is made to re-crystallize at a high-temperature, but kept below its melting point. In our experiment, Al, Ag, and Cu foils of 100 μm thickness were bonded on a glass substrate of 1 mm thickness using an intermediation layer of the same metal. After that, a heated quartz mold was pressed against each metal foil, and nano-patterning was carried out. Within the limits of the specifications of a used thermal nanoimprint system, the optimal imprint temperature for Al, Ag, and Cu foils was 500, 600, and 650 °C respectively. For all metals the imprint pressure and holding time were set as 20 MPa and 1 h. As a result of trial experiments, on the three kinds of metal foils we succeeded in forming line/space with a minimum linewidth of 350 nm; and concave and convex square dotted patterns with a minimum width of 500 nm. This technique required imprint pressure less than used in conventional direct-nanoimprinting at the room temperature. With this technique of nanofabrication, molds with a low mechanical strength could be used. © 2013 Springer-Verlag Berlin Heidelberg.


Gordon M.S.,Iowa State University | Fedorov D.G.,Japan National Institute of Advanced Industrial Science and Technology | Pruitt S.R.,Iowa State University | Slipchenko L.V.,Purdue University
Chemical Reviews | Year: 2012

Research work conducted in the field of fragmentation methods, a route to accurate calculations on large systems, is presented. The restricted variational space (RVS) analysis and the constrained space orbital variations (CSOV) method improve on the KM scheme by employing fully antisymmetrized intermediate wave functions. Wu et al. developed a density-based energy decomposition (EDA), in which the energies of the intermediate states are calculated using the densities of the fragments, rather than their wave functions. In 2008, Xie et al. modified the formulation of X-Pol to obtain rigorously analytic gradients. In 2002, Inadomi et al. proposed the FMO-MO method, which according to the classification of fragment methods as discussed above, belongs to a different category from the rest of the FMO methods. Bettens et al., have developed an energy based fragmentation method based on the idea of isodesmic reactions.


Taniguchi T.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2014

The reversal condition of magnetization in a nanomagnet under the effect of rotating magnetic field generated by a microwave is theoretically studied based on the Landau-Lifshitz-Gilbert equation. In a rotating frame, the microwave produces a dc magnetic field pointing in the reversed direction, which energetically stabilizes the reversed state. We find that the microwave simultaneously produces a torque preventing the reversal. It is pointed out that this torque leads to a jump in the reversal field with respect to the frequency. We derive the equations determining the reversal fields in both the low- and high-frequency regions from the energy balance equation. The validities of the formulas are confirmed by a comparison with the numerical simulation of the Landau-Lifshitz-Gilbert equation. © 2014 American Physical Society.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2015

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2014 are reviewed. Copyright © 2014 John Wiley & Sons, Ltd.


Tanaka Y.,Japan National Institute of Advanced Industrial Science and Technology
Physica C: Superconductivity and its Applications | Year: 2014

A basic design is proposed for a classical bit element of a superconducting circuit that mimics a frustrated multiband superconductor and is composed of an array of π-Josephson junctions (π-junction). The phase shift of π provides the lowest energy for one π-junction, but neither a π nor a zero phase shift gives the lowest energy for an assembly of π-junctions. There are two chiral states that can be used to store one bit information. The energy scale for reading and writing to memory is of the same order as the junction energy, and is thus in the same order of the driving energy of the circuit. In addition, random access is also possible. © 2014 Elsevier B.V. All rights reserved.


Nada H.,Japan National Institute of Advanced Industrial Science and Technology
Crystal Growth and Design | Year: 2011

A molecular dynamics simulation was conducted to analyze the growth shape of an ice crystal from water near its melting point under high pressure. The simulation was performed using a constant-volume system in which a cylindrical ice crystal grew freely in all directions perpendicular to the crystals c-axis. As the ice crystal grew in the system, the pressure gradually increased to approximately 2000 atm. The growth rate gradually decreased to near zero because the increase in pressure caused melting point depression. As the pressure increased to 2000 atm, the ice crystal grew as a hexagonal plate with {101̄0} prismatic plane facets clearly visible. The simulation indicated a fluctuation of the growth front geometry in the a-axis direction; the formation of a molecularly sharp corner was repeatedly disrupted during growth. The molecularly sharp corner appeared transiently as a result of the layer-by-layer growth of prismatic plane layers toward the corner. When corner formation was disrupted, a transient, molecularly flat, {112̄0} secondary prismatic plane appeared, but it was not a stable plane facet. The features of the ice crystal growth shape observed in this simulation were then compared with real systems. © 2011 American Chemical Society.


Artho C.,Japan National Institute of Advanced Industrial Science and Technology
International Journal on Software Tools for Technology Transfer | Year: 2011

Automated debugging attempts to locate the reason for a failure. Delta debugging minimizes the difference between two inputs, where one input is processed correctly while the other input causes a failure, using a series of test runs to determine the outcome of applied changes. Delta debugging is applicable to inputs or to the program itself, as long as a correct version of the program exists. However, complex errors are often masked by other program defects, making it impossible to obtain a correct version of the program through delta debugging in such cases. Iterative delta debugging extends delta debugging and removes a series of defects step by step, until the originally unresolved defect is isolated. The method is automated and managed to localize a bug in some real-life examples. © 2010 Springer-Verlag.


Fukuda J.-I.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2012

We study theoretically the effect of the variation of the elastic constants on the stability of cholesteric blue phases (BPs). We demonstrate that the stability of BPs is greatly enhanced when the bend elastic constant K 33 is smaller, in agreement with recent experimental findings. Larger splay (K 11) and twist (K 22) elastic constants also stabilize BPs. Our argument sheds light on the subtle effect of the variation of the elastic constants on the stability of BPs, and could guide the synthesis of liquid crystals with a wider temperature range of stable BPs. © 2012 American Physical Society.


Fukuda J.-I.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2012

We investigate theoretically, with the aid of numerical calculations based on a Landau-de Gennes theory, how two cubic cholesteric blue phases of a chiral liquid crystal, BP I and BP II, are stabilized when a guest component, such as a polymer network, is introduced and replace energetically costly defect regions. We show that the temperature range of stable BP I is significantly widened by the guest component, while the stability of BP II is only modestly enhanced. © 2012 American Physical Society.


Matsumura Y.,Japan National Institute of Advanced Industrial Science and Technology
International Journal of Hydrogen Energy | Year: 2013

Highly durable catalyst for high temperature methanol steam reforming is required for a compact hydrogen processor. Deactivation of a coprecipitated Cu/ZnO/ZrO2 catalyst modified with In2O3 is very gradual even in the high temperature methanol steam reforming mainly at 500 °C, but the initial activity is considerably low. Addition of Y2O3 to Cu/ZnO/ZrO2/In2O3 increases its initial activity due to the higher Cu surface amount, while the activity comes gradually close to that for the catalyst without Y2O3 during the reaction. Coprecipitation of Cu/ZnO/ZrO2/Y2O3/In2O3 on a zirconia support triply increases the overall activity by keeping the durability while the amount of the coprecipitated portion is a half of that without the support. On the composite catalyst, sintering of Cu particles is suppressed. The surface Cu amount is similar to that without the support, but the Cu surface activity is much higher probably because of the small Cu particle size. Copyright © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2013

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since June 2012 are reviewed. Copyright © 2012 John Wiley & Sons, Ltd.


Hayd J.,Karlsruhe Institute of Technology | Yokokawa H.,Japan National Institute of Advanced Industrial Science and Technology | Ivers-Tiffee E.,Karlsruhe Institute of Technology
Journal of the Electrochemical Society | Year: 2013

Miniature solid oxide fuel cells (μ-SOFCs) to be operated at temperatures between 400 and 600°C require custom-tailored electrolyte and electrode structures on the nanoscale. La0.6Sr0.4CoO 3-δ (LSC) thin-film cathodes derived by metal organic deposition (MOD) and with a nanoscaled microstructure were previously presented and exhibited an extremely low area specific polarization resistance of 7mΩ · cm2 at 600°C, increasing to 1.9 Ω · cm2 at 400°C. Naturally, grains and pores at the nanoscale are essential, but the decisive aspect to high-performance is presented here for the first time. In fact, our LSC thin-film cathodes exhibit enhanced oxygen surface-exchange properties, with a k* value up to 47 times better than that of bulks of (nominally) equal composition. The presence of secondary phases such as (La,Sr)2CoO4±δ and Co3O4 leads to this significant improvement, forming finely dispersed hetero-interfaces with LSC. Interesting enough, these secondary phases crystallize out during a low-temperature decomposition of the metal organic sol-gel film. Thermodynamic calculations revealed that low oxygen partial pressures must prevail for this, which occur during the oxidation of the organics. Deliberate stoichiometry variations with up to 10 % A-site (La, Sr) or B-site (Co) excess added to La0.6Sr0.4CoO 3-δ did not lead to further beneficial effects. © 2013 The Electrochemical Society.


Hase M.,University of Tsukuba | Tominaga J.,Japan National Institute of Advanced Industrial Science and Technology
Applied Physics Letters | Year: 2011

We report on evaluation of lattice thermal conductivity of GeTe/Sb 2Te3 superlattice (SL) by using femtosecond coherent phonon spectroscopy at various lattice temperatures. The time-resolved transient reflectivity obtained in amorphous and crystalline GeTe/Sb2Te 3 SL films exhibits the coherent A1 optical modes at terahertz (THz) frequencies with picoseconds dephasing time. Based on the Debye theory, we calculate the lattice thermal conductivity, including scattering by grain boundary and point defect, umklapp process, and phonon resonant scattering. The results indicate that the thermal conductivity in amorphous SL is less temperature dependent, being attributed to dominant phonon-defect scattering. © 2011 American Institute of Physics.


Shi X.,Economic Research Institute for ASEAN and East Asia ERIA | Goto S.,Japan National Institute of Advanced Industrial Science and Technology
Applied Energy | Year: 2013

This paper discusses the development of and policy towards biodiesel fuel (BDF) in the East Asia Summit (EAS) region (hereafter East Asia), with a focus on activities related to harmonizing BDF standards. To minimize problems with engines arising from the use of BDF, most EAS countries have established national BDF standards. However, these diverse standards cause barriers for BDF trade, and act against the regional interest in maximizing benefits from BDF production and utilization. Therefore, the East Asian policy-makers decided to harmonize BDF standards and a regional benchmark standard has been published. Through a comparative review of existing national standards against the benchmark, it finds that the harmonization is beneficial economically, and feasible technically, but stalled practically due to a lack of political determination. The key message from this paper is a call for political determination in East Asia to implement the harmonization. The findings of this paper may supplement the literature, enhance understanding of the East Asian case, and provide lessons and implications that may be helpful in advancing similar harmonization elsewhere. © 2013 Elsevier Ltd.


Matsumura Y.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Power Sources | Year: 2013

Catalytic activity of Cu/ZnO/ZrO2 for methanol steam reforming to hydrogen is stabilized by coprecipitation of Cu/ZnO/ZrO2 on a zirconia support. The coprecipitate coarsely covers the surface of the support while the particle structure is similar to that without the support. Deactivation of Cu/ZnO/ZrO2 in methanol steam reforming at 400 or 500 C is mitigated in the presence of the support which suppresses the sintering of Cu particles. Although the Cu content of a supported catalyst is a half of that without the support, the activity of the supported catalyst is appreciably higher after the reaction at 400 C for 5 h due to the higher Cu dispersion and surface activity. © 2013 Elsevier B.V. All rights reserved.


Matsumura Y.,Japan National Institute of Advanced Industrial Science and Technology
Applied Catalysis A: General | Year: 2013

Durable catalysts for methanol steam reforming are required for on-board hydrogen processors, and Pd-Zn alloy catalysts are the candidates. The addition of a small amount of aluminum to the coprecipitation of PdO/ZnO results in the formation of fine Pd-Zn particles after reduction with hydrogen at 500 C in comparison to a Pd-Zn/ZnO catalyst prepared by an impregnation technique or by coprecipitation without aluminum. Methanol steam reforming mainly into hydrogen and carbon dioxide proceeds over these catalysts at 300 C. The activity of the impregnated catalyst whose Pd content is 3 wt.% obviously decreases after the durability test at 550 C. On the other hand, that for the coprecipitated catalyst with aluminum is stable during the test and similar to the initial activity of the impregnated catalyst with the same Pd content of 3 wt.%. The surface activity of Pd-Zn on the coprecipitated catalyst is similar to that on the impregnated one after deactivation, but the Pd dispersion in the coprecipitate is significantly high. The activity of a Pd-Zn catalyst (Pd content, 3 wt.%) formed from PdO/ZnO/Al2O3 coprecipitated on a zirconia support is stable and significantly higher than that for the coprecipitated catalyst without the support. In the composite catalyst, the Pd-Zn particles are stabilized and probably ultrafine. It is estimated that a high surface activity is produced on the ultrafine particles by strongly interacting with the ZnO particles stabilized on the support surface. © 2013 Elsevier B.V. All rights reserved.


Suemori A.,Japan National Institute of Advanced Industrial Science and Technology
Protein Engineering, Design and Selection | Year: 2013

In order to elucidate the molecular mechanism of the catalytic reaction and enzyme conformation, we substituted 53 conserved residues identified by aligning 92 p-hydroxybenzoate hydroxylase sequences and 19 non-conserved residues selected from crystallographic studies of Pseudomonas fluorescens NBRC14160 p-hydroxybenzoate hydroxylase with 19 other naturally occurring amino acids, yielding a database of 619 active single mutants. The database contained 365 and 254 active single mutants for 44/53 conserved residues and 19 non-conserved residues, respectively; the data included main activity, sub-activity for NADPH and NADPH reaction specificity. Active mutations were not observed for the G14, Q102, G160, E198, R220, R246, N300, F342 and G387 conserved residues, and only one active mutant was obtained at the G9, G11, G187, D286, Y201, R214 and G295 conserved residues and the S13, E32 and R42 non-conserved residues. Only seven active mutants with higher activity than the wild-type enzyme were observed at conserved residues, and only two were observed at non-conserved residues. The 365 mutants at conserved residues included 64 active mutants with higher NADPH reaction specificity than the wild-type enzyme, and some Y181X single mutants exhibited considerable changes in NADPH reaction specificity. A Y181X/L268G double-mutant database was constructed to computationally analyze the effects of these substitutions on structural conformation and function. These results indicated that some conserved or non-conserved residues are important for structural stability or enzyme function. © The Author 2013. Published by Oxford University Press. All rights reserved.


Mariotti D.,University of Ulster | Mitra S.,University of Ulster | Svrcek V.,Japan National Institute of Advanced Industrial Science and Technology
Nanoscale | Year: 2013

Quantum confined silicon nanocrystals (Si-ncs) exhibit intriguing properties due to silicon's indirect bandgap and their highly reactive surfaces. In particular the interplay of quantum confinement with surface effects reveals a complex scenario, which can complicate the interpretation of Si-nc properties and prediction of their corresponding behaviour. At the same time, the complexity and interplay of the different mechanisms in Si-ncs offer great opportunities with characteristics that may not be achievable with other nano-systems. In this context, a variety of carefully surface-engineered Si-ncs are highly desirable both for improving our understanding of Si-nc photo-physics and for their successful integration in application devices. Here we firstly highlight a selection of theoretical efforts and experimental surface engineering approaches and secondly we focus on recent surface engineering results that have utilized novel plasma-liquid interactions. © 2013 The Royal Society of Chemistry.


Matsugi A.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Physical Chemistry Letters | Year: 2013

Previous studies on the photodissociation of C2H5 reported rate constants for H-atom formation several orders of magnitude smaller than that predicted by Rice-Ramsperger-Kassel-Marcus (RRKM) theory. This Letter provides a potential explanation for this anomaly, based on direct trajectory calculations of C2H5 dissociation. The trajectories reveal the existence of a roaming dissociation channel that leads to the formation of C2H3 and H2. This channel is found to proceed over the ridge between the transition state of H-atom elimination and that of bimolecular H-abstraction. The formed C2H3 radical can subsequently dissociate to C2H2 and a H atom; this secondary dissociation is suggested to be a potential reason for the unexpectedly slow H-atom formation observed in the photodissociation experiments. © 2013 American Chemical Society.


Matsunami D.,Tohoku University | Fujita A.,Japan National Institute of Advanced Industrial Science and Technology | Takenaka K.,Nagoya University | Kano M.,Tohoku University
Nature Materials | Year: 2014

First-order phase transitions are accompanied by a latent heat. Consequently, manipulating them by means of an external field causes a caloric effect. Although transitions from antiferromagnetic to paramagnetic states are not controlled by a magnetic field, a large barocaloric effect is expected when strong cross-correlations between the volume and magnetic order occur. Here we examine how geometric frustration in itinerant antiferromagnetic compounds can enhance the barocaloric effect. We study the thermodynamic behaviour of the frustrated antiferromagnet Mn3GaN, and report an entropy change of 22.3 J kg-1 K-1 that is concomitant with a hydrostatic pressure change of 139 MPa. Furthermore, the calculated value of the adiabatic temperature change reaches 5 K by depressurization of 93 MPa. The giant barocaloric effect in Mn3GaN is caused by a frustration-driven enhancement of the ratio of volume change against the pressure coefficient of the Néel temperature. This mechanism for enhancing the barocaloric effect can form the basis for a new class of materials for solid-state refrigerants. © 2014 Macmillan Publishers Limited. All rights reserved.


Kobayashi T.,Japan National Institute of Advanced Industrial Science and Technology
Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition | Year: 2014

Histogram-based features have significantly contributed to recent development of image classifications, such as by SIFT local descriptors. In this paper, we propose a method to efficiently transform those histogram features for improving the classification performance. The (L1-normalized) histogram feature is regarded as a probability mass function, which is modeled by Dirichlet distribution. Based on the probabilistic modeling, we induce the Dirichlet Fisher kernel for transforming the histogram feature vector. The method works on the individual histogram feature to enhance the discriminative power at a low computational cost. On the other hand, in the bag-of-feature (BoF) frame- work, the Dirichlet mixture model can be extended to Gaussian mixture by transforming histogram-based local descriptors, e.g., SIFT, and thereby we propose the method of Dirichlet-derived GMM Fisher kernel. In the experiments on diverse image classification tasks including recognition of subordinate objects and material textures, the pro- posed methods improve the performance of the histogram- based features and BoF-based Fisher kernel, being favor- ably competitive with the state-of-the-arts. © 2014 IEEE.


Wang L.,Ohio State University | Fujiwara S.,Ohio State University | Fujiwara S.,Japan National Institute of Advanced Industrial Science and Technology | Somers D.E.,Ohio State University
EMBO Journal | Year: 2010

Many core oscillator components of the circadian clock are nuclear localized but how the phase and rate of their entry contribute to clock function is unknown. TOC1/PRR1, a pseudoresponse regulator (PRR) protein, is a central element in one of the feedback loops of the Arabidopsis clock, but how it functions is unknown. Both TOC1 and a closely related protein, PRR5, are nuclear localized, expressed in the same phase, and shorten period when deficient, but their molecular relationship is unclear. Here, we find that both proteins interact in vitro and in vivo through their conserved N-termini. TOC1-PRR5 oligomerization enhances TOC1 nuclear accumulation two-fold, most likely through enhanced nuclear import. In addition, PRR5 recruits TOC1 to large subnuclear foci and promotes phosphorylation of the TOC1 N-terminus. Our results show that nuclear TOC1 is essential for normal clock function and reveal a mechanism to enhance phase-specific TOC1 nuclear accumulation. Interestingly, this process of regulated nuclear import is reminiscent of similar oligomeric pairings in animal clock systems (e.g. timeless/period and clock/cycle), suggesting evolutionary convergence of a conserved mechanism across kingdoms. © 2010 European Molecular Biology Organization.


White R.J.,Max Planck Institute of Colloids and Interfaces | Yoshizawa N.,Japan National Institute of Advanced Industrial Science and Technology | Antonietti M.,Max Planck Institute of Colloids and Interfaces | Titirici M.-M.,Max Planck Institute of Colloids and Interfaces
Green Chemistry | Year: 2011

The hydrothermal synthesis of nitrogen-doped monolithic carbon aerogels derived from sustainable precursors (i.e.d-glucose and ovalbumin) is presented. The protein acts as nitrogen donor and surface stabilizing agent in this saccharide hydrothermal carbonization, to generate high surface area aerogels (>240 m 2g -1) composed of functional continuous large diameter mesopores with excellent hierarchical transport architecture. Post-carbonization treatment controls surface chemistry (e.g. C or N condensation), facilitating tuneable physicochemical properties on a unique continuous 3D carbonaceous pore structure. This highly flexible synthesis lays the basis for the development of a new generation of sustainable (heteroatom-doped) porous carbon aerogels suitable for a range of high value applications. © 2011 The Royal Society of Chemistry.


Garzoni M.,University of Applied Sciences and Arts Southern Switzerland | Okuro K.,University of Tokyo | Ishii N.,Japan National Institute of Advanced Industrial Science and Technology | Aida T.,University of Tokyo | Pavan G.M.,University of Applied Sciences and Arts Southern Switzerland
ACS Nano | Year: 2014

The possibility to arrange biological molecules into ordered nanostructures is an important issue in nano- and biotechnology. Nature offers a wide range of molecular "bricks" (e.g., proteins, oligonucleotides, etc.) that spontaneously assemble into more complex hierarchical systems with unique functionalities. Such molecular building blocks can be also used for the construction of nanomaterials with peculiar properties (e.g., DNA origami). In some cases, molecular glues able to bind biomolecules and to induce their assembly can be used to control the final structure and properties in a convenient way. Here we provide molecular-level description of how molecular glues designed to stick to the surface of microtubules (MTs) can control and transform the α/β-tubulin assembly upon temperature decreasing. By means of all-atom molecular dynamics (MD) simulations, we compared the adhesion to the MT surface of three molecular glues bearing the same guanidinium ion surface adhesive groups, but having different architecture, i.e., linear or dendritic backbone. Our evidence demonstrates that the adhesive properties of the different molecular glues are dependent on the shape they assume in solution. In particular, adhesion data from our MD simulations explain how globular- or linear-like molecular glues respectively stabilize MTs or transform them into a well-defined array of α/β-tubulin rings at 15 C, where MTs naturally depolymerize. The comprehension of the MT transformation mechanism provides a useful rationale for designing ad hoc molecular glues to obtain ordered protein nanostructures from different biological materials. © 2013 American Chemical Society.


Nada H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Physical Chemistry C | Year: 2014

Molecular dynamics simulations were conducted to investigate the conformation and dynamics of an aspartic acid molecule near the {104} and {110} planes of a CaCO3 calcite crystal, near the acute and obtuse [114̄] step edges on the {104} plane, and near kinks formed at the step edges. The simulations indicate that the amino acid binds indirectly to the {104} plane, whereas it binds directly to the {110} plane. The simulations also indicate that the acid binds directly to the acute step edge but does not bind to the obtuse step edge. These differences in the binding of the acid to the planes and the step edges were attributed to a difference in the structure of the surrounding water. The simulations also indicate that the acid binds to the kink formed at both the acute and the obtuse step edges, if a Ca2+ ion is placed at the corner of the kink. The binding was much stronger at the kink than at the planes and the step edges. © 2014 American Chemical Society.


Kimura T.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Materials Chemistry A | Year: 2014

A series of macroporous titania films were fabricated using spherical soft colloids of polystyrene-block-poly(oxyethylene) (PS-b-PEO) and the macrostructure was systematically varied from reticular to spherical and large spherical according to the synthetic conditions. This macroreticular structure, which has never been organized by templating with organic assemblies/aggregates to date, was obtained with the controlled condensation of oxide frameworks in the presence of the soft PS-b-PEO colloids. The formation of reticular type pores was very sensitive to the synthetic conditions, which were optimized one-by-one for improving this unique colloidal PS-b-PEO templating approach for the precise structural design of inorganic oxide film as a more extendable method. Such spaces in the artificial reticular structure by continuous titania frameworks were designed in the range of macroscale to mesoscale. Accordingly, a new family of reticular type porous materials, which are suitable as porous platforms with very high surface area and allow smooth/rapid diffusion of targeted molecules, will be provided by this colloidal templating approach of organic block copolymer combined with the controlled condensation of frameworks for a variety of compositions. © 2014 the Partner Organisations.


Shinoda W.,Japan National Institute of Advanced Industrial Science and Technology | DeVane R.,Procter and Gamble | Klein M.L.,Temple University
Current Opinion in Structural Biology | Year: 2012

Coarse-grained (CG) molecular models are now widely used to understand the structure and functionality of macromolecular self-assembling systems. In the last few years, significant efforts have been devoted to construct quantitative CG models based on data from molecular dynamics (MD) simulations with more detailed all-atom (AA) intermolecular force fields as well as experimental thermodynamic data. We review some of the recent progress pertaining to the MD simulation of self-assembling macromolecular systems, using as illustrations the application of CG models to probe surfactant and lipid self-assembly including liposome and dendrimersome formation as well as the interaction of biomembranes with nanoparticles. © 2012 Elsevier Ltd.


Green M.A.,University of New South Wales | Emery K.,National Renewable Energy Laboratory | Hishikawa Y.,Japan National Institute of Advanced Industrial Science and Technology | Warta W.,Fraunhofer Institute for Solar Energy Systems | Dunlop E.D.,European Commission - Joint Research Center Ispra
Progress in Photovoltaics: Research and Applications | Year: 2013

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since January 2013 are reviewed. Copyright © 2013 John Wiley & Sons, Ltd. Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since January 2013 are reviewed. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2013 John Wiley & Sons, Ltd.


Ogura T.,Japan National Institute of Advanced Industrial Science and Technology
PLoS ONE | Year: 2012

Scanning electron microscopy (SEM) is an important tool for the nanometre-scale analysis of the various samples. Imaging of biological specimens can be difficult for two reasons: (1) Samples must often be left unstained to observe detail of the biological structures; however, lack of staining significantly decreases image contrast. (2) Samples are prone to serious radiation damage from electron beam. Herein we report a novel method for sample preparation involving placement on a new metal-coated insulator film. This method enables obtaining high-contrast images from unstained proteins and viruses by scanning electron microscopy with minimal electron radiation damage. These images are similar to those obtained by transmission electron microscopy. In addition, the method can be easily used to observe specimens of proteins, viruses and other organic samples by using SEM. © 2012 Toshihiko Ogura.


Huang L.-T.,MingDao University | Michael Gromiha M.,Japan National Institute of Advanced Industrial Science and Technology
Bioinformatics | Year: 2010

Summary: The accurate prediction of protein folding rate change upon mutation is an important and challenging problem in protein folding kinetics and design. In this work, we have collected experimental data on protein folding rate change upon mutation from various sources and constructed a reliable and non-redundant dataset with 467 mutants. These mutants are widely distributed based on secondary structure, solvent accessibility, conservation score and long-range contacts. From systematic analysis of these parameters along with a set of 49 amino acid properties, we have selected a set of 12 features for discriminating the mutants that speed up or slow down the folding process. We have developed a method based on quadratic regression models for discriminating the accelerating and decelerating mutants, which showed an accuracy of 74% using the 10-fold cross-validation test. The sensitivity and specificity are 63% and 76%, respectively. The method can be improved with the inclusion of physical interactions and structurebased parameters. © The Author 2010. Published by Oxford University Press.


Tateno H.,Japan National Institute of Advanced Industrial Science and Technology
Methods in Molecular Biology | Year: 2014

The glycan microarray is now an essential tool used to study lectins. With this technique, glycan-binding specificity can be easily assessed by incubation with an array immobilizing a series of glycans. Glycan microarrays have been developed by numerous research groups around the world. Among the available microarrays, our glycan microarray has two unique characteristics: one is the incorporation of an evanescent-field fluorescence detection system and the other is the use of multivalent glycopolymers. These two unique properties allow the highly sensitive detection of only nanogram quantities of lectins even in crude samples such as cell lysates and cell culture media. Thus, this system is suitable for the initial screening of lectins, lectin-like molecules, lectin candidates, and lectin mutants. Here I describe the protocols employed to analyze the glycan-binding specificity of lectins using our glycan microarray system. © 2014 Springer Science+Business Media New York.


Futahashi R.,Japan National Institute of Advanced Industrial Science and Technology
Current Opinion in Insect Science | Year: 2016

Dragonflies including damselflies are colorful and large-eyed insects, which show remarkable sexual dimorphism, color transition, and color polymorphism. Recent comprehensive visual transcriptomics has unveiled an extraordinary diversity of opsin genes within the lineage of dragonflies. These opsin genes are differentially expressed between aquatic larvae and terrestrial adults, as well as between dorsal and ventral regions of adult compound eyes. Recent topics of color formation in dragonflies are also outlined. Non-iridescent blue color is caused by coherent light scattering from the quasiordered nanostructures, whereas iridescent color is produced by multilayer structures. Wrinkles or wax crystals sometimes enhances multilayer structural colors. Sex-specific and stage-specific color differences in red dragonflies is attributed to redox states of ommochrome pigments. © 2016 The Author. Published by Elsevier Inc.


Ogura T.,Japan National Institute of Advanced Industrial Science and Technology
PLoS ONE | Year: 2014

Scanning electron microscopy (SEM) is a powerful tool for the direct visualization of biological specimens at nanometrescale resolution. However, images of unstained specimens in water using an atmospheric holder exhibit very poor contrast and heavy radiation damage. Here, we present a new form of microscopy, the frequency transmission electric-field (FTE) method using SEM, that offers low radiation damage and high-contrast observation of unstained biological samples in water. The wet biological specimens are enclosed in two silicon nitride (SiN) films. The metal-coated SiN film is irradiated using a focused modulation electron beam (EB) at a low-accelerating voltage. A measurement terminal under the sample holder detects the electric-field frequency signal, which contains structural information relating to the biological specimens. Our results in very little radiation damage to the sample, and the observation image is similar to the transmission image, depending on the sample volume. Our developed method can easily be utilized for the observation of various biological specimens in water. © 2014 Toshihiko Ogura.


Miyashita K.,Japan National Institute of Advanced Industrial Science and Technology
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

In spot markets for trading fishes, single-sided auctions are used for clearing the market by virtue of its promptness and simplicity, which are important in dealing with perishable goods. However, in those auctions, sellers cannot participate in price-making process. A standard double auction market collects bids from traders and matches buyers' higher bids and sellers' lower bids to find the most efficient allocation, assuming that values of unsold items remain unchanged. Nevertheless, in the spot fish market, sellers suffer loss when they fail to sell the fish, whose salvage value is lost due to perishability. To solve the problem, we investigate the suitable design of an online double auction for fishery markets, where bids arrive dynamically with their time limits. Our market mechanism aims at improving traders' profitability by reducing trade failures in the face of uncertainty of incoming/leaving bids. We developed a heuristic matching rule for the market to prioritize traders' bids based on their time-criticality and evaluated its performance empirically. © 2013 Springer-Verlag.


Katoh K.,Osaka University | Katoh K.,Japan National Institute of Advanced Industrial Science and Technology | Standley D.M.,Osaka University
Molecular Biology and Evolution | Year: 2013

We report a major update of the MAFFT multiple sequence alignment program. This version has several new features, including options for adding unaligned sequences into an existing alignment, adjustment of direction in nucleotide alignment, constrained alignment and parallel processing, which were implemented after the previous major update. This report shows actual examples to explain how these features work, alone and in combination. Some examples incorrectly aligned by MAFFT are also shown to clarify its limitations. We discuss how to avoid misalignments, and our ongoing efforts to overcome such limitations. © 2013 The Author 2013. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.


Akiyama M.,Japan National Institute of Advanced Industrial Science and Technology
Applied Physics Letters | Year: 2010

BaMgSiO4 (BMS) can be sensed to blue light (wavelength λ=405 nm) by doped europium (Eu). Eu doped BMS turns to bright pink, and is bleached by green light (λ=475-532 nm) irradiation in several seconds. The coloration-decoloration process is repeatable and first. The colored state hardly changes for over 480 h (20 days), and is stable even at 100 °C. The blue-green light photochromism can be explained by electron transfers between doped Eu and oxygen defects. The doped Eu broadens the absorption band of BMS, and supplies excited electrons. The oxygen defects form electron traps, which catch excited electrons, and become F-like color centers. © 2010 American Institute of Physics.


Asai Y.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Physics Condensed Matter | Year: 2013

The possibilities of an enhanced thermoelectric figure of merit value, ZT, in a nanostructured junction are examined for a wide range of parameter values in a theoretical model. Our research shows that the figure of merit can take a very large maximum, which depends both on the length and the energy gap values. The maximum of ZT is achieved when the Fermi level of the electrodes is aligned to the edge of the electronic transmission function of the junction, where both the conductance and the Seebeck constant are significantly enhanced. On the basis of our results, we conclude that nanowires and molecular junctions form a special class of systems where a large ZT can be expected in some cases. © 2013 IOP Publishing Ltd.


Tanaka Y.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Optics (United Kingdom) | Year: 2013

Three-dimensional controlled manipulation of individual micro-objects requires multiple optical tweezers that can be independently controlled in a 3D working space with high spatiotemporal resolution. Here, the author presents 3D multiple optical tweezers based on a time-shared scanning technique with an electrically focus tunable lens for axial steering and a two-axis steering mirror for lateral steering. Four typical examples of 3D controlled manipulation, including the rotation of a single bead on its axis, are demonstrated in real time. The optical system design and the control method are also described. © 2013 IOP Publishing Ltd.


Aburatani S.,Japan National Institute of Advanced Industrial Science and Technology
Gene Regulation and Systems Biology | Year: 2011

Revealing the gene regulatory systems among DNA and proteins in living cells is one of the central aims of systems biology. In this study, I used Structural Equation Modeling (SEM) in combination with stepwise factor analysis to infer the protein-DNA interactions for gene expression control from only gene expression profles, in the absence of protein information. I applied my approach to infer the causalities within the well-studied serial transcriptional regulation composed of GAL-related genes in yeast. This allowed me to reveal the hierarchy of serial transcriptional regulation, including previously unclear protein-DNA interactions. The validity of the constructed model was demonstrated by comparing the results with previous reports describing the regulation of the transcription factors. Furthermore, the model revealed combinatory regulation by Gal4p and Gal80p. In this study, the target genes were divided into three types: those regulated by one factor and those controlled by a combination of two factors.© the author(s), publisher and licensee Libertas Academica Ltd.


Fukuda J.-I.,Japan National Institute of Advanced Industrial Science and Technology | Fukuda J.-I.,University of Ljubljana | Zumer S.,University of Ljubljana | Zumer S.,Jozef Stefan Institute
Physical Review Letters | Year: 2010

In our numerical study based on a phenomenological description of strongly confined liquid crystalline blue phase I (BP I), we find several novel structures characterized by specific configurations of topological disclination lines. The thickness of the system is of the order of the dimension of the unit cell of the bulk BP I, and the confining surfaces adopts homeotropic anchoring. The structures include an array of double-helix disclination lines accompanied by an orthorhombic lattice of double-twist cylinders, and two parallel arrays of winding disclination lines almost perpendicular to each other. © 2010 The American Physical Society.


Umemoto K.,University of Minnesota | Wentzcovitch R.M.,University of Minnesota | Saito S.,Tokyo Institute of Technology | Miyake T.,Japan National Institute of Advanced Industrial Science and Technology
Physical Review Letters | Year: 2010

We have investigated by first principles the electronic, vibrational, and structural properties of bct C4, a new form of crystalline sp3 carbon recently found in molecular dynamics simulations of carbon nanotubes under pressure. This phase is transparent, dynamically stable at zero pressure, and more stable than graphite beyond 18.6 GPa. Coexistence of bct C4 with M carbon can explain better the x-ray diffraction pattern of a transparent and hard phase of carbon produced by the cold compression of graphite. Its structure appears to be intermediate between that of graphite and hexagonal diamond. These facts suggest that bct C4 is an accessible form of sp3 carbon along the graphite-to-hexagonal diamond transformation path. © 2010 The American Physical Society.


Mawatari Y.,Japan National Institute of Advanced Industrial Science and Technology
Superconductor Science and Technology | Year: 2013

We have theoretically investigated the magnetic response of two-dimensional (2D) arrays of superconducting and soft magnetic strips, which are regarded as models of dc magnetic metamaterials. The anisotropy of the macroscopic permeabilities depends on whether the applied magnetic field is parallel to the wide surface of the strips (μ∥) or perpendicular (μ⊥). For the 2D arrays of superconducting strips, 0 < μ⊥/μ0 ≪ μ∥/μ0 ≃ 1, whereas for the 2D arrays of soft magnetic strips, μ∥/μ0 ≫ μ/μ0 ≃ 1, where μ0 is the vacuum permeability. We also demonstrate that strong anisotropy of the macroscopic permeability can be obtained for hybrid arrays of superconducting and soft magnetic strips, where μ∥/μ0 ≫ 1 ≫ μ⊥/μ0 > 0. © 2013 IOP Publishing Ltd.


Johansson F.,Kyushu University | Toh H.,Japan National Institute of Advanced Industrial Science and Technology
BMC Bioinformatics | Year: 2010

Background: Conservation and variation scores are used when evaluating sites in a multiple sequence alignment, in order to identify residues critical for structure or function. A variety of scores are available today but it is not clear how different scores relate to each other.Results: We applied 25 conservation and variation scores to alignments from the Catalytic Site Atlas (CSA). We calculated distances among scores based on correlation coefficients, and constructed a dendrogram of the scores by average linking cluster analysis. The cluster analysis showed that most scores fall into one of two groups--substitution matrix based group and frequency based group respectively. We also evaluated the scores' performance in predicting catalytic sites and found that frequency based scores generally perform best.Conclusions: Conservation and variation scores can be classified into mainly two large groups. When using a score to predict catalytic sites, frequency based scores that also consider a background distribution are most successful. © 2010 Johansson and Toh; licensee BioMed Central Ltd.


Hibino T.,Japan National Institute of Advanced Industrial Science and Technology
Applied Clay Science | Year: 2014

The feasibility of nanocomposite polymer hydrogels as anion adsorbents was explored by using agarose-layered double hydroxide (LDH) hybrids. Also, to obtain fundamental data for possible applications such as slow drug release of more complex hybrid hydrogels such as ionic polymer-LDHs, the absorption ability of LDH highly dispersed in an uncharged polymer, agarose, was evaluated. An aqueous colloidal dispersion of LDH containing lactate was mixed with agarose and water. Then, the mixture was boiled to dissolve the agarose and cooled to form a gel. It was confirmed by SEM that LDH nanoplates were uniformly dispersed in the resulting nanocomposite hydrogels. LDH restacked from the colloidal dispersion by evaporation of water was used for comparison. Samples were treated with an acetate-buffer/NaCl solution to replace lactate anions in LDHs with Cl- anions and to exclude contaminating carbonate anions from LDHs. Adsorption ability for SO4 2- was evaluated as the amount of adsorbed anion per unit quantity of LDH by normalizing the amounts of adsorbed anion by the Al content (mol/mol). The adsorption ability of the LDH nanoplates in the hybrid gels was lower than that of the restacked LDH when the LDH contents were low. When LDH/agarose ratio was lower, agarose polymer probably covered the LDH nanoplates more, which may have hindered anion access to the LDH nanoplates. When the LDH content was increased so that the ratio of LDH to agarose approached 1:1 by weight, the adsorption ability of the LDH nanoplates was about the same as or slightly greater than that of the restacked LDH. In addition, when LDH:agarose=1:1, anion selectivity among SO4 2-, I- and HPO4 2- was about the same between the hybrid gel and the restacked LDH. © 2013 Elsevier B.V.


Bentien A.,University of Aarhus | Okada T.,Japan National Institute of Advanced Industrial Science and Technology | Kjelstrup S.,Norwegian University of Science and Technology
Journal of Physical Chemistry C | Year: 2013

Electrokinetic energy conversion for pumping or power generation has for the past decade regained attention with focus on applications within pumping in nanofluidics or microgenerators. Little experimental work has been published and mostly in relation to clean-room fabricated nanopores. In the present study, it is suggested that electrokinetic energy conversion has a potential as future decentralized electrical energy sources, if polymer membranes are used. On the basis of new electrokinetic measurements and literature data, we have made a systematic study of commercially available nanoporous polymer membranes and found a promising first law efficiency of 5.5% in one polymer-electrolyte system. It is likely that future more rigorous and targeted studies will find even larger conversion efficiencies. © 2012 American Chemical Society.


Kim J.,Hanyang University | Akinaga H.,Japan National Institute of Advanced Industrial Science and Technology
Applied Physics Letters | Year: 2011

The saturation magnetization of MnAs films epitaxially grown on GaAs(001) substrates exhibited temperature hysteresis in the temperature range of 10-45 °C. We investigated the cause of the temperature hysteresis using temperature- and field-controlled magnetic force microscopy (MFM). The MFM results showed that inside the ferromagnetic α-MnAs stripes of the film at 30 °C, 180° domains were formed during cooling but a single domain state was developed during heating. Despite the cooling procedure, a single domain state was found inside the α -MnAs stripes when a magnetic field of 800 Oe was applied. From these results, the spontaneous magnetization of the α -MnAs phase was ascribed to the temperature hysteresis. © 2011 American Institute of Physics.


Dutta S.,National Taiwan University | Wu K.C.-W.,National Taiwan University | Kimura T.,Japan National Institute of Advanced Industrial Science and Technology
Chemistry of Materials | Year: 2015

The advent of ordered porous materials and nanomaterials with controlled porosity has opened new frontiers in the field of materials chemistry. Materials with ordered micro-, meso-, and macropores, including hierarchical pores, provide exceptional functions that make them suitable for use in a wide variety of advanced device materials, media for electrochemical phenomena, and components for sophisticated functional products. In the fabrication of ordered porous structures that would enhance the function of materials, the shrinkage of frameworks plays a vital role in the formation of unique structures of porous materials and nanomaterials. To reveal the role of isotropic and anisotropic shrinkages in the process of pore construction, this review provides an overview of previous experiments that have focused on such framework shrinkage of highly porous materials prepared using organic templates and further assesses how shrinkage (isotropic for particles and anisotropic for films) are fascinating for porous materials design. This type of study will stimulate new strategies regarding the emerging challenges and opportunities to utilize high-grade and predictable design for obtaining nanomaterials including unique porous materials of relevance in multiple areas including energy. © 2015 American Chemical Society.


Hara J.,Japan National Institute of Advanced Industrial Science and Technology
Chemosphere | Year: 2011

The degradation of dieldrin by ferric sulphide (FeS2) in aqueous solution was investigated when shielded against sunlight. An oxidative dechlorination process was observed under aerobic and anaerobic conditions; oxygen volume changed the degradation rate of dieldrin and the generation rate of reaction products. The dechlorination rate under microaerophilic conditions was fastest among the anaerobic to air oxygen concentrations. For this experiment, over 99% of the dieldrin was degraded, and 90% of the released chloride was detected after 30d under 10μmol oxygen. The major reaction products were different depending on the dose of oxygen. In the case of aerobic conditions, low molecular weight organic acids, such as formic acid, lactic acid, and oxalic acid, were generated as major reaction products. However, under anaerobic conditions, C16H22O4 (dibutyl phthalate) and C6H13ClO (3-chloro-4-methyl-2-pentanol) were detected as reaction intermediates, and small amounts of succinic acid, malonic acid, and formic acid were also generated. These reactions proceed by FeS2 interface reactions with H2O under anaerobic condition, or O2 under aerobic condition. © 2010 Elsevier Ltd.


Kutsuna S.,Japan National Institute of Advanced Industrial Science and Technology
International Journal of Chemical Kinetics | Year: 2013

Henry's law constants of six kinds of hydrochlorofluorocarbons (HCFCs) were determined at 313-353 K by means of a phase-ratio variation headspace method: KH=KH353 exp (-ΔH sol /R(1/T-1/353)) and (KH 353 in M atm-1, ΔHsol in kJ mol-1) = (0.0070 ± 0.0006, -23 ± 2), (0.0038 ± 0.0011, -22 ± 10), (0.0065 ± 0.0007, -21 ± 3), (0.0026 ± 0.0007, -23 ± 8), (0.0016 ± 0.0003, -30 ± 4), and (0.0022 ± 0.0003, -25 ± 4), respectively, for HCFC-141b (CH3CCl2F), HCFC-142b (CH3CClF2), HCFC-123 (CF3CHCl 2), HCFC-124 (CF3CHClF), HCFC-225ca (CF3CF 2CHCl2), and HCFC-225cb (CClF2CF 2CHClF). Errors represent two standard deviations only for the fitting. The decay of headspace partial pressures of these HCFCs via hydrolysis was discerned only for CF3CHCl2 and CF3CF 2CHCl2 under the experimental conditions examined. Rate constants (kOH- in M-1 s-1) for aqueous reactions of CF3CF2CHCl2 and CF 3CHCl2 with OH- at 313-353 K were determined to be (0.57±0.04) exp (-(11,300±600)×(1/T-1/353)) and (2.9±0.2)×10-4 exp (-(8800±900)×(1/T-1/353)), respectively, from monitoring changes in headspace partial pressure over prescribed concentrations of aqueous NaOH as a function of the headspace time duration and concentration of aqueous NaOH. The calculations performed included consideration of gas-water equilibrium and hydrolysis at both headspace and room temperatures. The calculation for CF3CHCl2 also included consideration of salting-out effects: The salting coefficient of NaCl on a natural log basis was determined to be 0.36 ± 0.06 M-1, and this value was used for consideration of the salting-out effect of NaOH. Whereas the activation energy for CF3CF2CHCl2 was greater than that for CF3CHCl2, the kOH- value at 353 K of CF3CF2CHCl2 was 103 times larger than that of CF3CHCl2, indicating that reaction mechanisms for these two HCFCs differed from each other. The aqueous reaction of CF3CF2CHCl2 with OH- was found to proceed through dehydrofluorination on the basis of detection of CF3CFï£CCl2 as a primary degradation product of the reaction and proportionality of the rate constants to both concentrations of CF3CF2CHCl2 and OH-. © 2013 Wiley Periodicals, Inc.


Kimura T.,Japan National Institute of Advanced Industrial Science and Technology | Yamauchi Y.,Japan National Institute of Materials Science | Yamauchi Y.,Japan Science and Technology Agency
Langmuir | Year: 2012

A wide variety of synthetic approaches from homogeneous precursor solutions have so far been developed for precise structural design of materials in multiscale. In organic templating approaches for porous materials design, we have recently developed a new approach to fabricate colloidal polystyrene-block-poly(oxyethylene) (PS-b-PEO) templated large pores that can be controlled in thick films of aluminum organophosphonate (AOP). In this study, we extended this approach using colloidal PS-b-PEO aggregates to aerosol-assisted synthesis for the fabrication of spherical particles. Structural variations (morphology and porous structure) depended on the synthetic conditions, which were mainly investigated by using electron microscopies (SEM and TEM). In addition to the insight on the colloidal PS-b-PEO templating of spherical pores in AOP spheres, it was found that colloidal PS-b-PEO aggregates were flexible for further design of pore shape that was strongly affected by external morphology. In this context, we proposed this method as flexible colloidal PS-b-PEO templating to fabricate unusual macroporous structures during morphological control from precursor solutions containing colloidal PS-b-PEO aggregates. The insights will be promising for precise construction of unique devices using porous materials templated by colloidal organic aggregates. In addition, we found a useful water adsorption desorption behavior over the macroporous AOP bulky powders when the macropores were connected through large pores, which is also significant for future development of AOP-based porous materials. © 2012 American Chemical Society.


A new fluorescent probe displayed a large increase of fluorescence emission upon binding to proteins due to the cancellation of dansyl fluorescence quenching by the cyanopyranyl moiety. To take advantage of this phenomenon, qualitative and quantitative analyses of proteins were performed in the solution or in the gel for electrophoresis. © 2013 The Royal Society of Chemistry.


Matsugi A.,University of Tokyo | Matsugi A.,Japan National Institute of Advanced Industrial Science and Technology | Miyoshi A.,University of Tokyo
Proceedings of the Combustion Institute | Year: 2013

A detailed chemical kinetic model for the pyrolysis of toluene and subsequent formation of polycyclic aromatic hydrocarbons (PAHs) was constructed for the low pressure (∼10 Torr) experimental condition of Shukla et al. [J. Phys. Chem. A 11 1 (2007) 8308-8324; J. Phys. Chem. A 112 (2008) 2362-2369]. The kinetic model for PAHs formation in premixed flames proposed by Richter et al. [Proc. Combust. Inst. 30 (2005) 1397-1405] was used as a starting-point model and was revised for a number of reactions. Computational and empirical estimates of the rate constants were performed for important reactions involving resonance stabilized hydrocarbon radicals. The resultant model consists of 289 species and 947 reactions. The numerical simulation with the proposed model satisfactory reproduced the formation of two- and three-ring aromatic hydrocarbons observed in the mass spectrometric experiments for the low-pressure flow-reactor pyrolysis of toluene and toluene/acetylene and toluene/benzene mixtures at temperatures 1136-1507 K by Shukla et al. The sensitivity and flux analyses indicated the importance of the reactions of resonance stabilized radicals such as benzyl, fulvenallenyl and propargyl radicals for the PAHs formation processes. © 2012 The Combustion Institute. Published by Elsevier Inc. All rights reserved.


Uchida N.,Tohoku University | Ohzono T.,Japan National Institute of Advanced Industrial Science and Technology
Soft Matter | Year: 2010

Orientational order in buckling-induced microwrinkles of elastic membranes on soft substrates is investigated both theoretically and experimentally. Anisotropic orientational correlation in wrinkles induced by isotropic compression is characterized using an orientational order parameter, and is explained by an effective elastic free energy that suppresses Gaussian curvature. We find that orientationally correlated domains tend to extend in ± 45° directions from the local wrinkle orientation. Excellent agreement is obtained between numerical, theoretical, and experimental results. © 2010 The Royal Society of Chemistry.


Ito F.,Japan National Institute of Advanced Industrial Science and Technology
Chemical Physics | Year: 2010

Infrared spectra of CHF2Cl dimer and the CHF2Cl⋯H2O complex have been observed in Xe matrix. A comparison of the spectra with the results of DFT calculations led us to the following conclusion: the structure of CHF2Cl dimer is a head-to-tail type with intermolecular Cl⋯H interaction, whereas CHF2Cl⋯H2O has a C-H⋯O intermolecular hydrogen bond, in contrast with the analogous CH3F⋯H2O complex [Y. Futami, S. Kudoh, M. Takayanagi, M. Nakata, Chem. Phys. Lett. 357 (2002) 209]. © 2010 Elsevier B.V. All rights reserved.


Nakamura H.,Japan Advanced Institute of Science and Technology | Ohto T.,Japan Advanced Institute of Science and Technology | Ishida T.,Japan National Institute of Advanced Industrial Science and Technology | Asai Y.,Japan Advanced Institute of Science and Technology
Journal of the American Chemical Society | Year: 2013

Superior long-range electric transport has been observed in several organometallic wires. Here, we discuss the role of the metal center in the electric transport and examine the possibility of high thermoelectric figure of merit (ZT) by controlling the quantum resonance effects. We examined a few metal center (and metal-free) terpyridine-based complexes by first-principles calculations and clarified the role of the metals in determining the transport properties. Quasi-resonant tunneling is mediated by organic compounds, and narrow overlapping resonance states are formed when d-electron metal centers are incorporated. Distinct length (L) and temperature (T) dependencies of thermopower from semiconductor materials or organic molecular junctions are presented in terms of atomistic calculations of ZT with and without considering the phonon thermal conductance. We present an alternative approach to obtain high ZT for molecular junctions by quantum effect. © 2013 American Chemical Society.


Harigaya K.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Computational and Theoretical Nanoscience | Year: 2012

Nano-carbon materials are investigated intensively. In this paper, the edge-state in nanographene materials with zigzag edges is studied theoretically. In particular, while the inter-layer hopping interactions are considered, we prove that edge states exist at the energy of the Dirac point in the doubly stacked nanographene, and in the case of the infinitely-wide lower layer case. This property applies both for the A-B and A-C stackings. Copyright © 2012 American Scientific Publishers All rights reserved.


Funahashi M.,Kagawa University | Sonoda A.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Materials Chemistry | Year: 2012

A liquid-crystalline (LC) semiconductor based on perylene tetracarboxylic bisimide (PTCBI) bearing four 1,1,1,3,3-pentamethyldisiloxane chains was synthesized. This LC PTCBI derivative exhibits ordered columnar phases and the low temperature columnar phase is retained below room temperature. The electron mobility in the ordered columnar phase of this compound at room temperature exceeds 0.1 cm2 V-1 s-1. Moreover, this compound is soluble in various organic solvents, except alcohols, and thin films in which the columnar aggregates are aligned parallel to the substrates are produced by spin-coating. In particular, LC thin films in which the columnar stacks are uniaxially oriented can be produced by a friction transfer method. © 2012 The Royal Society of Chemistry.