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Patent
Japan Science, Technology Agency and Tokyo Institute of Technology | Date: 2015-02-12

The invention related to a material that can stably hold an imide anion (NH^(2)) therein even in the atmosphere or in a solvent, and a method for synthesizing the material and a use of the material. A mayenite-type compound into which imide anions are incorporated at a concentration of 110^(18 )cm^(3 )or more are provided. The mayenite-type compound can be produced by heating a mayenite-type compound including electrons or free oxygen ions in a cage thereof, in liquefied ammonia at 450 to 700 C. and at a pressure of 30 to 100 MPa. The compound has properties such that active imide anions can be easily incorporated into the compound and the active imide anions can be easily released in the form of ammonia from the compound, and the compound has chemical stability.


Patent
Japan Science and Technology Agency | Date: 2015-04-22

A combined-blade-type open flow path device being a fluid flow path device where a plurality of flow paths are adjacent to each other, the combined-blade-type open flow path device comprising: a substrate configured to constitute a bottom portion of the flow paths; and a plurality of blades erected on a surface of the substrate, the plurality of blades configured to constitute side walls of the flow paths, wherein the plurality of blades are erected in a plurality of numbers at a space in a direction from an upstream side to a downstream side of a flow of the fluid, and conduction of the fluid between the flow paths adjacent at the space is made possible, and wherein the flow of the fluid is made possible by one end of the flow path being in contact with the fluid.


Patent
Japan Science and Technology Agency | Date: 2015-01-21

The present invention provides a method for producing adult oligodendrocyte progenitor cells from proliferative oligodendrocyte progenitor cells, and a pharmaceutical composition having for an active ingredient thereof adult OPC produced according to that method. The method for producing adult OPC of the present invention is characterized by inducing proliferating OPC to differentiate into adult OPC by culturing in the presence of a ligand of a thyroid hormone receptor or retinoic acid receptor in a low oxygen environment. The present invention further provides adult OPC produced according to the production method of the present invention, and a pharmaceutical composition having these adult OPC as an active ingredient thereof.


A method for authenticating a security mark containing a photochromic compound can provide higher security performance. The method comprises a process of irradiating a security mark containing a photochromic compound with excitation light, a process of acquiring first security information on a time-dependent change in the absorption spectrum and/or reflection spectrum of the security mark after the irradiation with excitation light, and a process of checking the acquired first security information against previously acquired first security information on the security mark. In this method, the security mark preferably contains two or more photochromic compounds different from one another in color development and/or in quenching rate after the color development in a photochromic reaction.


Patent
Japan Science and Technology Agency | Date: 2015-01-09

The method for producing a perovskite metal oxynitride of the present invention, comprises: a hydrogenation step (A) of forming a perovskite oxyhydride in which an oxide ion (O2) and a hydride ion (H) coexist, by reducing a perovskite oxide through a reductive oxygen elimination reaction using a metal hydride; and a nitriding step (B) of forming a perovskite oxynitride containing a nitride ion (N3) by heat-treating the perovskite oxyhydride in the presence of a nitrogen source substance at a temperature of 300 C. or higher and 600 C. or lower and exchanging the hydride ion (H) for a nitride ion (N3).


Patent
Japan Science and Technology Agency | Date: 2015-01-09

The ammonia synthesis catalyst of the present invention, comprises: a powder of a perovskite oxyhydride having hydride (H^()) incorporated therein as a support; and a metal or a metal compound exhibiting a catalytic activity for ammonia synthesis, supported on the support, and the perovskite oxyhydride is represented by ATiO_(3-x)H_(x )(wherein A represents Ca, Sr, or Ba, and 0.1x0.6).


Patent
Japan Science and Technology Agency | Date: 2015-02-24

A thermal emission source capable of switching the intensity of light at a high response speed similarly to a photoelectric conversion element. A thermal emission source includes: a two-dimensional photonic crystal including a slab in which an n-layer made of an n-type semiconductor, a quantum well structure layer having a quantum well structure, and a p-layer made of a p-type semiconductor are stacked in the mentioned order in the thickness direction, wherein modified refractive index areas (air holes) whose refractive index differs from the refractive indices of the n-layer, the p-layer and the quantum well structure layer are cyclically arranged in the slab so as to resonate with a specific wavelength of light corresponding to a transition energy between the subbands in a quantum well in the quantum well structure layer; and a p-type electrode and an n-type electrode for applying, to the slab, a voltage which is negative on the side of the p-layer and positive on the side of the n-layer.


A method for authenticating a security mark containing a photochromic compound can provide higher security performance. The method comprises a process of irradiating a security mark containing a photochromic compound with excitation light, a process of acquiring first security information on a time-dependent change in the absorption spectrum and/or reflection spectrum of the security mark after the irradiation with excitation light, and a process of checking the acquired first security information against previously acquired first security information on the security mark. In this method, the security mark preferably contains two or more photochromic compounds different from one another in color development and/or in quenching rate after the color development in a photochromic reaction.


Patent
Japan Science and Technology Agency | Date: 2017-01-04

Provided is an optical network which makes it possible to increase frequency use efficiency of an optical signal when transmitting wavelength division multiplexed light. One or more optical path cross connection devices (OXC) through which a wavelength division multiplexed light signal travels when being transmitted from a prescribed transmission node to a prescribed receiving node, wherein when an optical channel inputted from an input optical fiber (Fi1-Fin) is routed or switched to one or more output optical fibers (Fo1-FoN), a plurality of optical channels adjacent on a frequency axis which are outputted to the same output optical fiber (FoN) in the input optical fibers (Fi1-Fin) are routed or switched to an output optical fiber by demultiplexing the plurality of optical channels as one bundle without demultiplexing each of the optical channels individually. Thus, it is possible to increase frequency use efficiency of an optical signal when transmitting wavelength division multiplexed light, because the instances of optical channel filtering are reduced and the loss caused by filtering is decreased.


Patent
Japan Science and Technology Agency | Date: 2017-01-04

The present invention provides a thermal emission source capable of switching the intensity of light at a high response speed similarly to a photoelectric conversion element. A thermal emission source 10 includes: a two-dimensional photonic crystal 12 including a slab 11 in which an n-layer 112 made of an n-type semiconductor, a quantum well structure layer 114 having a quantum well structure, and a p-layer 111 made of a p-type semiconductor are stacked in the mentioned order in the thickness direction, wherein modified refractive index areas (air holes 121) whose refractive index differs from the refractive indices of the n-layer 112, the p-layer 111 and the quantum well structure layer 114 are cyclically arranged in the slab 11 so as to resonate with a specific wavelength of light corresponding to a transition energy between the subbands in a quantum well in the quantum well structure layer 114; and a p-type electrode 131 and an n-type electrode 132 for applying, to the slab 11, a voltage which is negative on the side of the p-layer 111 and positive on the side of the n-layer 112.


Patent
Japan Science and Technology Agency | Date: 2017-04-05

An inverse photoemission spectroscopy apparatus is configured to detect a light generated by the relaxation of electrons to an unoccupied state of a sample.The apparatus includes an electron source for generating electrons with which a sample is irradiated, a wavelength selector for extracting a light having a certain wavelength from the light generated in the sample, a photodetector for detecting the light extracted by the wavelength selector; and a focusing optics disposed between the sample and the photodetector. The electron source contains yttrium oxide as a thermionic emission material.


Patent
Japan Science and Technology Agency | Date: 2017-04-05

The present invention provides an alga that is modified to have suppressed expression of ATG8 through (i) overexpression of MEX1 and/or (ii) silencing of ATG8 with a miRNA and exhibits increased photosynthetic productivity to achieve increased biomass productivity in algal cells. The invention further provides a method of producing such a modified alga, a method of biomass production using such a modified alga, and starch produced using such a modified alga.


Patent
Japan Science, Technology Agency and Tokyo Institute of Technology | Date: 2017-01-11

The invention related to a material that can stably hold an imide anion (NH_(2)^(-)) therein even in the atmosphere or in a solvent, and a method for synthesizing the material and a use of the material. A mayenite-type compound into which imide anions are incorporated at a concentration of 1 10^(18) cm^(-3) or more are provided. The mayenite-type compound can be produced by heating a mayenite-type compound including electrons or free oxygen ions in a cage thereof, in liquefied ammonia at 450 to 700C and at a pressure of 30 to 100 MPa. The compound has properties such that active imide anions can be easily incorporated into the compound and the active imide anions can be easily released in the form of ammonia from the compound, and the compound has chemical stability.


Provided is a block copolymer that makes it possible to produce inorganic nanoparticles that can be dispersed in an organic solvent, the inorganic nanoparticles being of uniform size and a reducing agent not having to be used. A block copolymer including a catechol segment represented by formula (1).


Patent
Japan Science and Technology Agency | Date: 2017-01-25

Provided is a method for producing an aniline derivative by fermentation from a carbon source such as glucose. A method for producing an aniline derivative, the method including the following steps: production of microorganisms capable of producing 1.8 g/L or more of 4-aminophenylalanine (4APhe) under prescribed culture conditions by introducing at least three exogenous genes into microorganisms having the ability to biosynthesize 4-aminophenylpyruvic acid from chorismic acid; and production of at least one aniline derivative selected from the group consisting of 4-aminophenylalanine (4APhe), 4-aminocinnamic acid (4ACA), 2-(4-aminophenyl)aldehyde, 4-aminophenylacetic acid, and 4-aminophenethylethanol (4APE) by bringing these microorganisms into contact with a carbon source under conditions suited to the growth and/or maintenance of these microorganisms.


Patent
Japan Science and Technology Agency | Date: 2017-01-18

Provided is a transistor including: a piezoresistor 10 through which carriers conduct; a source 14 that injects the carriers into the piezoresistor; a drain 16 that receives the carriers from the piezoresistor; a piezoelectric material 12 that is located so as to surround the piezoresistor and applies a pressure to the piezoresistor; and a gate 18 that applies a voltage to the piezoelectric material applies so that the piezoelectric material applies a pressure to the piezoresistor.


Patent
Japan Science and Technology Agency | Date: 2017-03-15

The object of the present invention is to provide a polymer brush which forms phase-separated structure in a gas phase. The polymer brush according to the present invention comprises a substrate and a polymer layer wherein the polymer layer comprises polymer chains each of which has one end fixed on the substrate and other end free-ended, and wherein a state of phase-separation between a polymer dense part and a polymer thin part reversibly changes in the polymer layer.


Patent
Japan Science and Technology Agency | Date: 2017-01-18

A novel catalyst capable of selectively catalyzing conversion from glucose to fructose in water or in an aqueous solution is provided. The catalyst is a solid catalyst for a hydride isomerization reaction from glucose to fructose performed in water or in an aqueous solution, comprising a group 13 element oxide whose surface has been subjected to a phosphoric acid treatment.


Patent
Japan Science and Technology Agency | Date: 2017-04-19

As a calcium indicator protein having an excellent fluorescent characteristic and calcium reactivity, there is provided DNA in which one of a nucleotide sequence derivative of a calmodulin-binding sequence (ckkap sequence) of calcium/calmodulin-dependent protein kinase kinase and a nucleotide sequence encoding a calcium-binding sequence (CaM sequence) of calmodulin is linked to a 5 end of a nucleotide sequence encoding a fluorescent protein, and the other nucleotide sequence is linked to a 3 end of the nucleotide sequence encoding the fluorescent protein. The calcium indicator protein encoded by this DNA, which based on the derivative of the ckkap sequence as a binding domain for the calcium-bound CaM sequence, exhibits a fluorescent characteristic and calcium reactivity superior to those of conventional calcium indicator proteins.


Patent
Japan Science, Technology Agency and Tokyo Institute of Technology | Date: 2017-04-19

A catalyst is provided which is used for continuously synthesizing ammonia using a gas containing hydrogen and nitrogen as a raw material, wherein a transition metal which exhibits catalytic activity is supported by a support, and the support is a two-dimensional electride or a precursor thereof. The two-dimensional electride or the precursor thereof is a metal nitride represented by MxNyHz (M represents one or two or more of Group II metals selected from the group consisting of Mg, Ca, Sr and Ba, and x, y and z are in ranges of 1 x 11, 1 y 8, and 0 z 4 respectively, in which x is an integer, and y and z are not limited to an integer) or M_(3)N_(2) (M is the same as above), or a metal carbide selected from the group consisting of Y_(2)C, Sc_(2)C, Gd_(2)C, Tb_(2)C, Dy_(2)C, Ho_(2)C and Er_(2)C. These catalysts are used for continuously reacting nitrogen with hydrogen, which are raw materials, on the catalyst, wherein the reaction is performed in an ammonia synthesis reaction system under the preferable conditions of a reaction temperature which is equal to or higher than 100C and equal to or lower than 600C, and a reaction pressure which is equal to or higher than 10 kPa and lower than 20 MPa.


Eda G.,Imperial College London | Eda G.,National University of Singapore | Yamaguchi H.,Rutgers University | Voiry D.,Rutgers University | And 4 more authors.
Nano Letters | Year: 2011

A two-dimensional crystal of molybdenum disulfide (MoS 2) monolayer is a photoluminescent direct gap semiconductor in striking contrast to its bulk counterpart. Exfoliation of bulk MoS 2 via Li intercalation is an attractive route to large-scale synthesis of monolayer crystals. However, this method results in loss of pristine semiconducting properties of MoS 2 due to structural changes that occur during Li intercalation. Here, we report structural and electronic properties of chemically exfoliated MoS 2. The metastable metallic phase that emerges from Li intercalation was found to dominate the properties of as-exfoliated material, but mild annealing leads to gradual restoration of the semiconducting phase. Above an annealing temperature of 300 °C, chemically exfoliated MoS 2 exhibit prominent band gap photoluminescence, similar to mechanically exfoliated monolayers, indicating that their semiconducting properties are largely restored. © 2011 American Chemical Society.


Takao K.,National Institute for Physiological science | Takao K.,Japan Science and Technology Agency | Miyakawa T.,National Institute for Physiological science | Miyakawa T.,Japan Science and Technology Agency | Miyakawa T.,Health Science University
Proceedings of the National Academy of Sciences of the United States of America | Year: 2015

The use of mice as animal models has long been considered essential in modern biomedical research, but the role of mouse models in research was challenged by a recent report that genomic responses in mouse models poorly mimic human inflammatory diseases. Here we reevaluated the same gene expression datasets used in the previous study by focusing on genes whose expression levels were significantly changed in both humans and mice. Contrary to the previous findings, the gene expression levels in the mouse models showed extraordinarily significant correlations with those of the human conditions (Spearman's rank correlation coefficient: 0.43-0.68; genes changed in the same direction: 77-93%; P = 6.5 × 10-11 to 1.2 × 10-35). Moreover, meta-analysis of those datasets revealed a number of pathways/biogroups commonly regulated by multiple conditions in humans and mice. These findings demonstrate that gene expression patterns in mouse models closely recapitulate those in human inflammatory conditions and strongly argue for the utility of mice as animal models of human disorders.


Ito T.,National University of Singapore | Ito T.,Japan Science and Technology Agency
Current Opinion in Plant Biology | Year: 2011

Floral homeotic genes encode transcription factors and act as master regulators of flower development. The homeotic protein complex is expressed in a specific whorl of the floral primordium and determines floral organ identity by the combinatorial action. Homeotic proteins continue to be expressed until late in flower development to coordinate growth and organogenesis. Recent genomic studies have shown that homeotic proteins bind thousands of target sites in the genome and regulate the expression of transcription factors, chromatin components and various proteins involved in hormone biosynthesis and signaling and other physiological activities. Further, homeotic proteins program chromatin to direct the developmental coordination of stem cell maintenance and differentiation in shaping floral organs. © 2010 Elsevier Ltd.


Hara S.,Yamanashi University | Irie H.,Yamanashi University | Irie H.,Japan Science and Technology Agency
Applied Catalysis B: Environmental | Year: 2012

We prepared two types of SrTiO 3-based photocatalyst powders, Bi,Ga-doped SrTiO 3 and In,V-doped SrTiO 3. UV-visible reflectance spectra of these powders indicated that their band-gaps remained constant in comparison with that of SrTiO 3. In conjunction with the reported band structure control of oxides, our results indicated that Bi,Ga-doped SrTiO 3 and In,V-doped SrTiO 3 formed isolated mini-bands composed of Bi 6s orbitals in the forbidden band above the valence band, composed of O 2p, and V 3d orbitals below the conduction band, composed of Ti 3d, resulting in the observed visible-light absorption. Utilizing the prepared SrTiO 3-based photocatalysts, we established a two-step overall water-splitting system, in which simultaneous liberation of hydrogen and oxygen with a molar ratio of ~2:1 was observed in the presence of I - (NaI) under irradiation with UV-containing light. Moreover, visible light contributed the cycling of I -/IO 3 - redox mediators, resulting in enhanced hydrogen and oxygen liberation when compared to irradiation with UV light alone. © 2012 Elsevier B.V..


Aoki T.,Kagawa University | Aoyagi T.,Kyoto University | Aoyagi T.,Japan Science and Technology Agency
Physical Review Letters | Year: 2012

Co-evolution exhibited by a network system, involving the intricate interplay between the dynamics of the network itself and the subsystems connected by it, is a key concept for understanding the self-organized, flexible nature of real-world network systems. We propose a simple model of such coevolving network dynamics, in which the diffusion of a resource over a weighted network and the resource-driven evolution of the link weights occur simultaneously. We demonstrate that, under feasible conditions, the network robustly acquires scale-free characteristics in the asymptotic state. Interestingly, in the case that the system includes dissipation, it asymptotically realizes a dynamical phase characterized by an organized scale-free network, in which the ranking of each node with respect to the quantity of the resource possessed thereby changes ceaselessly. Our model offers a unified framework for understanding some real-world diffusion-driven network systems of diverse types. © 2012 American Physical Society.


Kubota Y.,National Institute for Physiological science | Kubota Y.,Graduate University for Advanced Studies | Kubota Y.,Japan Science and Technology Agency
Current Opinion in Neurobiology | Year: 2014

The cerebral cortical microcircuit is composed of pyramidal and non-pyramidal cells and subcortical and cortico-cortical afferents. These constitute a complex wiring structure that remains poorly understood. At least ten non-pyramidal cell subtypes are known. These innervate different target neuronal domains, and have a key role in regulating cortical neuronal activity. Gamma-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the cerebral cortex, and most cortical inhibitory synapses originate from non-pyramidal cells. Therefore, investigating the morphological and functional wiring properties of GABAergic non-pyramidal cells is critical to understanding the functional architecture of the cortical microcircuitry. This review focuses on current understanding of the different roles of inhibitory GABAergic non-pyramidal cell subtypes in cortical functions. © 2013 Elsevier Ltd.


Saijo N.,Nippon Telegraph and Telephone | Gomi H.,Japan Science and Technology Agency
PLoS ONE | Year: 2010

Background: When exposed to a continuous directional discrepancy between movements of a visible hand cursor and the actual hand (visuomotor rotation), subjects adapt their reaching movements so that the cursor is brought to the target. Abrupt removal of the discrepancy after training induces reaching error in the direction opposite to the original discrepancy, which is called an aftereffect. Previous studies have shown that training with gradually increasing visuomotor rotation results in a larger aftereffect than with a suddenly increasing one. Although the aftereffect difference implies a difference in the learning process, it is still unclear whether the learned visuomotor transformations are qualitatively different between the training conditions. Methodology/Principal Findings: We examined the qualitative changes in the visuomotor transformation after the learning of the sudden and gradual visuomotor rotations. The learning of the sudden rotation led to a significant increase of the reaction time for arm movement initiation and then the reaching error decreased, indicating that the learning is associated with an increase of computational load in motor preparation (planning). In contrast, the learning of the gradual rotation did not change the reaction time but resulted in an increase of the gain of feedback control, suggesting that the online adjustment of the reaching contributes to the learning of the gradual rotation. When the online cursor feedback was eliminated during the learning of the gradual rotation, the reaction time increased, indicating that additional computations are involved in the learning of the gradual rotation. Conclusions/Significance: The results suggest that the change in the motor planning and online feedback adjustment of the movement are involved in the learning of the visuomotor rotation. The contributions of those computations to the learning are flexibly modulated according to the visual environment. Such multiple learning strategies would be required for reaching adaptation within a short training period. © 2010 Saijo, Gomi.


Takesue H.,Nippon Telegraph and Telephone | Takesue H.,Japan Science and Technology Agency
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2010

We report a single-photon frequency down-conversion experiment. Using the difference frequency generation process in a periodically poled lithium niobate waveguide, we successfully observed the phase-preserved frequency down-conversion of a coherent pulse train with an average photon number per pulse of <1, from the 0.7 μm visible wavelength band to the 1.3 μm telecom band. We expect this technology to become an important tool for flexible photonic quantum networking, including the realization of quantum repeater systems over optical fiber using atom-photon entanglement sources for the visible wavelength bands. © 2010 The American Physical Society.


Chiba D.,Kyoto University | Chiba D.,Japan Science and Technology Agency | Fukami S.,NEC Corp | Shimamura K.,Kyoto University | And 3 more authors.
Nature Materials | Year: 2011

Electrical control of magnetic properties is crucial for device applicationsin the field of spintronics. Although the magnetic coercivity or anisotropy has been successfully controlled electrically in metals as well as in semiconductors, the electrical control of Curie temperature has been realized only in semiconductors at low temperature. Here, we demonstrate the room-temperature electrical control of the ferromagnetic phase transition in cobalt, one of the most representative transition-metal ferromagnets. Solid-state field effect devices consisting of a ultrathin cobalt film covered by a dielectric layer and a gate electrode were fabricated. We prove that the Curie temperature of cobalt can be changed by up to 12K by applying a gate electric field of about 2MVcm-1. The two-dimensionality of the cobalt film may be relevant to our observations. The demonstrated electric field effect in the ferromagnetic metal at room temperature is a significant step towards realizing future low-power magnetic applications. © 2011 Macmillan Publishers Limited. All rights reserved.


Eda G.,National University of Singapore | Fujita T.,Tohoku University | Fujita T.,Japan Science and Technology Agency | Yamaguchi H.,Rutgers University | And 3 more authors.
ACS Nano | Year: 2012

Nanoscale heterostructures with quantum dots, nanowires, and nanosheets have opened up new routes toward advanced functionalities and implementation of novel electronic and photonic devices in reduced dimensions. Coherent and passivated heterointerfaces between electronically dissimilar materials can be typically achieved through composition or doping modulation as in GaAs/AlGaAs and Si/NiSi or heteroepitaxy of lattice matched but chemically distinct compounds. Here we report that single layers of chemically exfoliated MoS 2 consist of electronically dissimilar polymorphs that are lattice matched such that they form chemically homogeneous atomic and electronic heterostructures. High resolution scanning transmission electron microscope (STEM) imaging reveals the coexistence of metallic and semiconducting phases within the chemically homogeneous two-dimensional (2D) MoS 2 nanosheets. These results suggest potential for exploiting molecular scale electronic device designs in atomically thin 2D layers. © 2012 American Chemical Society.


Tiemann L.,Nippon Telegraph and Telephone | Rhone T.D.,Nippon Telegraph and Telephone | Rhone T.D.,Japan Science and Technology Agency | Shibata N.,Tohoku University | And 2 more authors.
Nature Physics | Year: 2014

When the motion of electrons is restricted to a plane under a perpendicular magnetic field, a variety of quantum phases emerge at low temperatures, the properties of which are dictated by the Coulomb interaction and its interplay with disorder. At very strong magnetic field, the sequence of fractional quantum Hall liquid phases1 terminates in an insulating phase, which is widely believed to be due to the solidification of electrons into domains possessingWigner crystal2 order3-11. The existence of such Wigner crystal domains is signalled by the emergence of microwave pinning-mode resonances10,11, which reflect the mechanical properties characteristic of a solid. However, the most direct manifestation of the broken translational symmetry accompanying the solidification-the spatial modulation of particles' probability amplitudes-has not been observed yet. Here, we demonstrate that nuclear magnetic resonance provides a direct probe of the density topography of electron solids in the integer and fractional quantum Hall regimes. The data uncover quantum and thermal fluctuations of lattice electrons resolved on the nanometre scale.Ourresults pave theway to studies of other exotic phases with non-trivial spatial spin/charge order. © 2014 Macmillan Publishers Limited. All rights reserved.


Patent
Japan Science, Technology Agency and Ayabo Corporation | Date: 2014-05-26

Improvement of control of size and structure of nanoclusters with a nanocluster production apparatus is intended. Increase of an obtained amount and a yield of nanoclusters having size and structure, at least one of which is selected, is intended. A nanocluster production apparatus has a vacuum chamber, a sputtering source that generates plasma by pulse discharge, a pulse power supply that supplies a pulsed power to the sputtering source, a first inert gas supply device that supplies a first inert gas to the sputtering source, a cluster growth cell stored in the vacuum chamber and a second inert gas introduction device that introduces a second inert gas into the cluster growth cell.


Patent
Japan Science, Technology Agency and Ayabo Corporation | Date: 2016-04-13

Improvement of control of size and structure of nanoclusters with a nanocluster production apparatus is intended. Increase of an obtained amount and a yield of nanoclusters having size and structure, at least one of which is selected, is intended. A nanocluster production apparatus has a vacuum chamber, a sputtering source that generates plasma by pulse discharge, a pulse power supply that supplies a pulsed power to the sputtering source, a first inert gas supply device that supplies a first inert gas to the sputtering source, a nanocluster growth cell stored in the vacuum chamber and a second inert gas introduction device that introduces a second inert gas into the nanocluster growth cell.


News Article | November 11, 2015
Site: www.scientificcomputing.com

When performing numerical weather predictions, it is important that the simulation itself be accurate, but it is also key for real-world data, based on observations, to be accurately entered into the model. Typically, weather simulations work by having the computer conduct a number of simulations based on the current state, and then entering observational data into the simulation to nudge it in a way that puts it closer to the actual state. The problem of incorporating data in the simulation — data assimilation — has become increasingly complex with the large number of types of available data, such as satellite observations and measurements taken from ground stations. Typically, supercomputers today spend an approximately equal amount of time running the simulations and incorporating the real-world data. Now, with research that could lead to more accurate forecasts, researchers from the RIKEN Advanced Institute for Computational Science in Japan have run an enormous global weather simulation. They ran 10,240 simulations of a model of the global atmosphere divided into 112-km sectors, and then used data assimilation and statistical methods to come up with a model closely fitting the real data for a historical time period, between November 1 and November 8, 2011. The simulations were run on Japan’s flagship 10-petaflop K computer using NICAM, a simulation intended to accurately model the atmosphere. One of the key findings is that faraway observations, several thousand kilometers in distance, may have an impact on the eventual state of the weather forecast. Data from the Great Lakes region in the United States, for instance, can have an impact on the eventual state in Europe. This finding suggests the need for further research on advanced methods that can make better use of faraway observations, as this could potentially lead to an improvement of weather forecasts. According to Takemasa Miyoshi, who led the research team, “Forecasting is becoming better thanks to more powerful computers and better observational data from satellites and radars. We attempted to use a large number of samples using a relatively coarse simulation, and found that it performed quite well, fitting the actual data from the time period we chose. We are planning to use the power of the K computer’s successor, as it develops, to create tools that could be used for better weather forecasting.” The following two research projects funded by the Japan Science and Technology Agency (JST) CREST programs contributed to this achievement: In addition, the project was funded by: The research is featured in the November 2015 issue of Computer, IEEE Computer Society’s flagship publication. Citation: Takemasa Miyoshi, Keiichi Kondo, and Koji Terasaki, “Big Ensemble Data Assimilation in Numerical Weather Prediction,” Computer, vol. 48, no. 11, 2015, pp. 15–21; DOI: 10.1109/MC.2015.332.


News Article | March 22, 2016
Site: phys.org

For fabrication of organic ferroelectric devices, one of the problems to be solved is to make a homogeneous thin film. The developed printing technique that stimulates thin-film formation from a solution allows formation of highly uniform single-crystalline thin films of organic ferroelectrics. The thin-film device fabricated by the developed technique worked as a memory device with only 3 V which is lower than operation voltage of various memory devices. The developed technique is expected to accelerate the research and development on low power consumption device of printed electronics such as ferroelectric memories and nonvolatile semiconductor FETs. Details of the results will soon be published online in a German scientific journal, Advanced Materials. Active R&D of the "printed electronics", which applies printing technologies to the production of electronic devices by forming precise, high-quality, metallic and/or semiconducting patterns, has been conducted globally. So far, several printing methods have been enthusiastically developed to fabricate metallic wires and semiconductor layers for transistors, although the development of printing techniques for other types of materials has not been conducted enough. Ferroelectric materials could reduce the power consumption of electronic devices such as ferroelectric memories in IC cards and nonvolatile semiconductor FETs. Therefore, it is required to develop patterning techniques for ferroelectric thin films though printing technologies. Ferroelectric materials are generally composed of inorganic materials so that it was considered to be difficult to apply a printing process. Although organic ferroelectric polymer materials are applicable to a printing process, their ferroelectric characteristics are inferior to those of inorganic materials. In recent years, research and development of organic ferroelectrics composed of small molecules have advanced. Some new organic materials showing superior characteristics comparable to inorganic ones have been found. Though thin-film formation of these materials is indispensable for making them into devices, it is difficult to form thin films of the materials. Therefore, it was desired to develop a fabrication technique of uniform thin film without any pinholes through a printing process. AIST has been promoting the research and development of organic ferroelectric small molecules composed of light elements, which contain no rare metal nor toxic lead and could be suitable for print production technologies. It has developed many organic ferroelectrics, including a binary component molecular compound with excellent ferroelectric properties (AIST press release on January 24, 2005) and a single component material that exhibits the best ferroelectric properties at room temperature (AIST press release on February 12, 2010). To build them into devices, it is necessary to fabricate pinhole-free, uniform thin films with oriented molecules. These demands motivated the researchers to search an appropriate compound and to adopt an advanced printing technique. This study is supported by the Japan Science and Technology Agency through CREST, as "Creation of Materials Science for Advanced Ferroelectrics of Organic Compounds." (Research Period: FY2011 - FY2015) The researchers selected 2-methylbenzimidazole (MBI) as a promising candidate for an organic ferroelectric material (Fig. 1a). MBI is one of the hydrogen-bonded organic ferroelectric materials, is soluble in organic solvents, shows polarization reversal at a low coercive electric field (few tens kV/cm), and exhibits excellent ferroelectric properties at room temperature. Within a single crystal, remnant polarization P would appear in two orthogonal directions. In devices to which voltage is applied in a direction normal to the thin film, P should have a component normal to the thin film. MBI is expected to grow in plate-like crystals having a desired polarization direction. Figure 1b shows the schematics of the developed thin film print fabrication process under ambient pressure at room temperature. First, the surface of a 1 cm square SiO2/Si substrate was treated with hydrophilic/hydrophobic patterning consisting of a 100 µm line and space (L&S) structure. An array of crystalline thin films can be formed on the hydrophilic regions by shearing the solution of MBI with a flat blade and successive drying. Synchronized light extinction by rotating cross-polarizers in the crossed-Nicols optical micrographs indicated a high degree of crystallographic alignment of these thin plate-like crystals (Fig. 1c). The lattice parameters, crystal orientations, and directions of spontaneous polarization of the MBI film were determined by synchrotron X-ray diffraction measurements at the Photon Factory of KEK. A single diffraction spot (in the dashed red circle) was observed for each diffraction plane (Fig. 2a) suggesting the formation of a single crystal. Figures 2b and 2c show schematics of the molecular packing structure and crystal orientation on the substrate. It was found that one of the hydrogen-bonded chains is directed perpendicular to and another is parallel to the substrate surface, respectively. It means that the principal polarization axes are tilted by 45 degrees relative to the substrate surface. As the spontaneous polarization has a component perpendicular to the substrate, it may be possible to reverse the polarization in electrode/ferroelectric/electrode layered structure by applying voltage between upper and lower electrodes. A capacitor-type device using the plate-like crystals with about 1 μm thickness exhibited quasi-rectangular loops in the electric polarization (P) versus electric field (E) hysteresis experiments without additional thermal annealing (Fig. 3a). The devices exhibited polarization switching at a very low voltage of about 3–4 V at 10 Hz. The fatigue characteristics of switching were evaluated at frequencies of 10, 100, and 1000 Hz. The ferroelectric properties could be maintained until hundreds of thousands cycles at 1000 Hz (Fig. 3b). The researchers expected that the fatigue characteristics could be improved by optimizing the device structure. Piezoresponse force microscope (PFM) characterization provides microscopic information about the polarization reversal. Figure 4a shows various sizes of polarization reversal domains obtained by applying a constant DC bias of +20 V to the tip with a pulse duration varying from 10 to 1000 ms for a 1.0 µm thick film. The minimum domain size was ≈500 nm, whereas it increases logarithmically with increasing a pulse duration (Fig. 4b). This domain was found to be stable for at least 40 h under ambient pressure at room temperature. Phases of PFM images reveal that the polarization changes by not 90 degrees but 180 degrees (Fig. 4c). The researchers aim to develop manufacturing technologies of all-printed electronics devices by combining the developed printing technique for thin film formation and other printing techniques for fabricating metal wires and semiconductor thin films.


News Article | December 5, 2016
Site: www.eurekalert.org

MADISON, Wis. -- A team of researchers led by Yoshihiro Kawaoka, professor of pathobiological sciences at the University of Wisconsin-Madison School of Veterinary Medicine, has developed technology that could improve the production of vaccines that protect people from influenza B. That technology is an influenza B vaccine virus "backbone" that would allow producers to grow vaccine viruses at high yield in mammalian cell culture rather than in eggs. Using the backbone as a template to add vaccine-virus-specific components, it would offer protection against both lineages of influenza B that circulate in the human population. "We want to provide a system that produces influenza vaccines that are more efficacious," says Kawaoka. "It is better to produce influenza viruses for vaccine production in cells instead of eggs, but the problem is that influenza virus does not grow well in cell culture compared with embryonated eggs." The new technology may overcome that challenge. The team published its results Monday, Dec. 5, in the Proceedings of the National Academy of Sciences. Each year, the U.S. Food and Drug Administration, in collaboration with the Centers for Disease Control and Prevention and the World Health Organization, decides which strains of influenza virus to include in the seasonal flu vaccine. It typically includes two influenza A strains and two influenza B strains. Growing vaccine viruses in high-yield cell culture should improve the ability of seasonal vaccines to protect against influenza A and B because vaccine viruses grown in mammalian cell culture are less likely to mutate compared to those grown in eggs. Mutations can lead to vaccine viruses that no longer match the intended strains of influenza. "It may still not be perfect, but it will at least be substantially better than current vaccines," says Kawaoka, who notes no one else has successfully tried to produce high-yield influenza B vaccine virus before now. Last year, his research team created a high-yield influenza A vaccine virus candidate for cell culture production. Per the CDC, growing vaccine viruses in high-yield cell culture may also enable faster and potentially greater production of vaccine. This could improve the ability of health officials to respond during an influenza pandemic. To develop the influenza B vaccine virus backbone, Kawaoka's team screened influenza B viruses for random genetic mutations that led to improved replication. Using these mutants as templates, the researchers attached the genes that code for the surface proteins that trigger the human immune response (and thus offer protection in vaccinated individuals) -- HA (hemagglutinin) and NA (neuraminidase). They selected the combinations of backbone mutations that supported better growth in cell culture, identifying two candidate backbones that led to higher amounts of vaccine virus. The team identified the characteristics of each backbone that contributed to their improved yield and also found the backbones to be genetically stable. However, Kawaoka points out that more testing is required to discern whether they would increase vaccine virus yield under industrial conditions. Several companies and federal agencies have already contacted him about the influenza A and influenza B backbones, Kawaoka says, and he is hopeful the systems can be adopted by vaccine manufacturers and grown in cell culture facilities already available in the United States and Japan. Kawaoka's goal is to help develop more effective vaccines to protect people from influenza infection. According to the CDC, influenza sickens millions, hospitalizes hundreds of thousands, and kills tens of thousands of people each year in the U.S. "This is something we have to do," Kawaoka says. Kawaoka credits the Wisconsin Alumni Research Foundation for the support to complete this work. "Without that, we couldn't get it going," he says. In addition to WARF, the current study was funded by the National Institute of Allergy and Infectious Diseases, Center for Research on Influenza Pathogenesis; Scientific Research on Innovative Areas from the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Strategic Basic Research Program of the Japan Science and Technology Agency; and the Leading Advanced Projects for Medical Innovation from the Japan Agency for Medical Research and Development.


Home > Press > One-pot synthesis towards sulfur-based organic semiconductors A short and simple synthetic route for thiophene-fused aromatic compounds Abstract: Thiophene-fused polycyclic aromatic hydrocarbons (PAHs) are known to be useful as organic semiconductors due to their high charge transport properties. Scientists at Nagoya University have developed a short route to form various thiophene-fused PAHs by simply heating mono-functionalized PAHs with sulfur. This new method is expected to contribute towards the efficient development of novel thiophene-based electronic materials. Dr. Lingkui Meng, Dr. Yasutomo Segawa, Professor Kenichiro Itami of the JST-ERATO Itami Molecular Nanocarbon Project, Institute of Transformative Bio-Molecules (ITbM) of Nagoya University and Integrated Research Consortium on Chemical Sciences, and their colleagues have reported in the Journal of the American Chemical Society, on the development of a simple and effective method for the synthesis of thiophene-fused PAHs. Thiophene-fused PAHs are organic molecules composed of multiple aromatic rings including thiophene. Thiophene is a five-membered aromatic ring containing four carbon atoms and a sulfur atom. Thiophene-fused PAHs are known to be one of the most common organic semiconductors and are used in various electronic materials, such as in transistors, organic thin-film solar cells, organic electro-luminescent diodes and electronic devices. More recently, they have found use in wearable devices due to their lightweight and flexibility. Thienannulation (thiophene-annulation) reactions, a transformation that makes new thiophene rings via cyclization, leads to various thiophene-fused PAHs. Most conventional thienannulation methods require the introduction of two functional groups adjacent to each other to form two reactive sites on PAHs before the cyclization can take place. Thus, multiple steps are required for the preparation of the substrates. As a consequence, a more simple method to access thiophene-fused PAHs is desirable. A team led by Yasutomo Segawa, a group leader of the JST-ERATO project, and Kenichiro Itami, the director of the JST-ERATO project and the center director of ITbM, has succeeded in developing a simple and effective method for the formation of various thiophene-fused PAHs. They have managed to start from PAHs that have only one functional group, which saves the effort of installing another functional group, and have performed the thienannulation reactions using elemental sulfur, a readily available low cost reagent. The reactions can be carried out on a multigram scale and can be conducted in a one-pot two-step reaction sequence starting from an unfunctionalized PAH. This new approach can also generate multiple thiophene moieties in a single reaction. Hence, this method has the advantage of offering a significant reduction in the number of required steps and in the reagent costs for thiophene-fused PAH synthesis compared to conventional methods. The researchers have shown that upon heating and stirring the dimethylformamide solution of arylethynyl group-substituted PAHs and elemental sulfur in air, they were able to obtain the corresponding thiophene-fused PAHs. The arylethynyl group consists of an alkyne (a moiety with a carbon-carbon triple bond) bonded to an aromatic ring. The reaction proceeds via a carbon-hydrogen (C-H) bond cleavage at the position next to the arylethynyl group (called the ortho-position) on PAHs, in the presence of sulfur. As the ortho-C-H bond on the PAH can be cleaved under the reaction conditions, prior functionalization (installation of a functional group) becomes unnecessary. Arylethynyl-substituted PAHs are readily accessible by the Sonogashira coupling, which is a cross-coupling reaction to form carbon-carbon bonds between an alkyne and a halogen-substituted aromatic compound. The synthesis of thiophene-fused PAHs can also be carried out in one-pot, in which PAHs are subjected to a Sonogashira coupling to form arylethynyl-substituted PAHs, followed by direct treatment of the alkyne with elemental sulfur to induce thienannulation. "Actually, we coincidentally discovered this reaction when we were testing different chemical reactions to synthesize a new molecule for the Itami ERATO project," says Yasutomo Segawa, one of the leaders of this study. "At first, most members including myself felt that the reaction may have already been reported because it is indeed a very simple reaction. Therefore, the most difficult part of this research was to clarify the novelty of this reaction. We put in a significant amount of effort to investigate previous reports, including textbooks from more than 50 years ago as well as various Internet sources, to make sure that our reaction conditions had not been disclosed before," he continues. The team succeeded in synthesizing more than 20 thiophene-fused PAHs. They also revealed that multiple formations of thiophene rings of PAHs substituted with multiple arylethynyl groups could be carried out all at once. Multiple thiophene-fused PAHs were generated from three-fold and five-fold thienannulations, which generated triple thia[5]helicene (containing three thiophenes) and pentathienocorannulene (containing five thiophenes), respectively. The pentathienocorannulene was an unprecedented molecule that was synthesized for the first time. "I was extremely happy when I was able to obtain the propeller-shaped triple thia[5]helicene and hat-shaped pentathienocorannulene, because I have always been aiming to synthesize exciting new molecules since I joined Professor Itami's group," says Lingkui Meng, a postdoctoral researcher who mainly conducted the experiments. "We had some problems in purifying the compounds but we were delighted when we obtained the crystal structures of the thiophene compounds, which proved that the desired reactions had taken place." "The best part of this research for me is to discover that our C-H functionalization strategy on PAHs could be applied to synthesize structurally beautiful molecules with high functionalities," says Segawa. "The successful synthesis of a known high-performance organic semiconductive molecule, (2,6-bis(4-n-octylphenyl)- dithieno[3,2-b:2?,3?-d]thiophene (the lower right of Figure 4), from a relatively cheap substrate opens doors to access useful thiophene compounds in a rapid and cost-effective manner." "We hope that ongoing advances in our method may lead to the development of new organic electronic devices, including semiconductor and luminescent materials," say Segawa and Itami. "We are considering the possibilities to make this reaction applicable for making useful thiophene-fused PAHs, which would lead to the rapid discovery and optimization of key molecules that would advance the field of materials science." About Nagoya University JST-ERATO Itami Molecular Nanocarbon Project was launched at Nagoya University in April 2014. This is a 5-year project that seeks to open the new field of nanocarbon science. This project entails the design and synthesis of as-yet largely unexplored nanocarbons as structurally well-defined molecules, and the development of novel, highly functional materials based on these nanocarbons. Researchers combine chemical and physical methods to achieve the controlled synthesis of well-defined uniquely structured nanocarbon materials, and conduct interdisciplinary research encompassing the control of molecular arrangement and orientation, structural and functional analysis, and applications in devices and biology. The goal of this project is to design, synthesize, utilize, and understand nanocarbons as molecules. About WPI-ITbM The Institute of Transformative Bio-Molecules (ITbM) at Nagoya University in Japan is committed to advance the integration of synthetic chemistry, plant/animal biology and theoretical science, all of which are traditionally strong fields in the university. ITbM is one of the research centers of the Japanese MEXT (Ministry of Education, Culture, Sports, Science and Technology) program, the World Premier International Research Center Initiative (WPI). The aim of ITbM is to develop transformative bio-molecules, innovative functional molecules capable of bringing about fundamental change to biological science and technology. Research at ITbM is carried out in a "Mix-Lab" style, where international young researchers from various fields work together side-by-side in the same lab, enabling interdisciplinary interaction. Through these endeavors, ITbM will create "transformative bio-molecules" that will dramatically change the way of research in chemistry, biology and other related fields to solve urgent problems, such as environmental issues, food production and medical technology that have a significant impact on the society. About JST-ERATO ERATO (The Exploratory Research for Advanced Technology), one of the Strategic Basic Research Program, aims to form a headstream of science and technology, and ultimately contribute to science, technology, and innovation that will change society and the economy in the future. In ERATO, a Research Director, a principal investigator of ERATO research project, establishes a new research base in Japan and recruits young researchers to implement his or her challenging research project within a limited time frame. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


News Article | December 28, 2016
Site: www.eurekalert.org

Reproducibility is a necessity for science but has often eluded researchers studying the lifetime of organic light-emitting diodes (OLEDs). Recent research from Japan sheds new light on why: impurities present in the vacuum chamber during fabrication but in amounts so small that they are easily overlooked. Organic light-emitting diodes use a stack of organic layers to convert electricity into light, and these organic layers are most commonly fabricated by heating source materials in vacuum to evaporate and deposit them onto a lower temperature substrate. While issues affecting the efficiency of OLEDs are already well understood, a complete picture of exactly how and why OLEDs degrade and lose brightness over time is still missing. Complicating matters is that devices fabricated with seemingly the same procedures and conditions but by different research groups often degrade at vastly different rates even when the initial performance is the same. Unable to attribute these reproducibility issues to known sources such as the amount of residual water in the chamber and the purity of the starting materials, a report published online in Scientific Reports on December 13, 2016, adds a new piece to the puzzle by focusing on the analysis of the environment in the vacuum chamber. "Although we often idealize vacuums as being clean environments, we detected many impurities floating in the vacuum even when the deposition chamber is at room temperature," says lead author Hiroshi Fujimoto, chief researcher at Fukuoka i3-Center for Organic Photonics and Electronics Research (i3-OPERA) and visiting associate professor of Kyushu University. Because of these impurities in the deposition chamber, the researchers found that the time until an OLED under operation dims by a given amount because of degradation, known as the lifetime, sharply increased for OLEDs that spent a shorter time in the deposition chamber during fabrication. This trend remained even after considering changes in residual water and source material purity, indicating the importance of controlling and minimizing the device fabrication time, a rarely discussed parameter. Research partners at Sumika Chemical Analysis Service Ltd. (SCAS) confirmed an increase of accumulated impurities with time by analyzing the materials that deposited on extremely clean silicon wafers that were stored in the deposition chamber when OLED materials were not being evaporated. Using a technique called liquid chromatography-mass spectrometry, the researchers found that many of the impurities could be traced to previously deposited materials and plasticizers from the vacuum chamber components. "Really small amounts of these impurities get incorporated into the fabricated devices and are causing large changes in the lifetime," says Professor Chihaya Adachi, director of Kyushu University's Center for Organic Photonics and Electronics Research (OPERA), which also took part in the study. In fact, the new results suggest that the impurities amount to less than even a single molecular layer. To improve lifetime reproducibility, a practice often adopted in industry is the use of dedicated deposition chambers for specific materials, but this can be difficult in academic labs, where often only a limited number of deposition systems are available for testing a wide variety of new materials. In these cases, deposition chamber design and cleaning in addition to control of the deposition time are especially important. "This is an excellent reminder of just how careful we need to be to do good, reproducible science," comments Professor Adachi. For more information, see "Influence of vacuum chamber impurities on the lifetime of organic light-emitting diodes," Scientific Reports 6, 38482 (2016); doi: 10.1038/srep38482. This work was performed by research groups at Kyushu University's Center for Organic Photonics and Electronics Research (OPERA), the Fukuoka i3-Center for Organic Photonics and Electronics Research (i3-OPERA), and the Institute of System, Information Technology and Nanotechnology (ISIT) in cooperation with Sumika Chemical Analysis Service Ltd. (SCAS). This research is ongoing in part under the Adachi Molecular Exciton Engineering Project funded by the Exploratory Research for Advanced Technology (ERATO) program of the Japan Science and Technology Agency (JST).


Innan H.,Graduate University for Advanced Studies | Innan H.,Japan Science and Technology Agency | Kondrashov F.,Center for Genomic Regulation
Nature Reviews Genetics | Year: 2010

Gene duplications and their subsequent divergence play an important part in the evolution of novel gene functions. Several models for the emergence, maintenance and evolution of gene copies have been proposed. However, a clear consensus on how gene duplications are fixed and maintained in genomes is lacking. Here, we present a comprehensive classification of the models that are relevant to all stages of the evolution of gene duplications. Each model predicts a unique combination of evolutionary dynamics and functional properties. Setting out these predictions is an important step towards identifying the main mechanisms that are involved in the evolution of gene duplications. © 2010 Macmillan Publishers Limited. All rights reserved.


Morimoto M.,Rikkyo University | Morimoto M.,Japan Science and Technology Agency | Irie M.,Rikkyo University
Journal of the American Chemical Society | Year: 2010

The photomechancial effect of a rectangular plate two-component cocrystal composed of a photochromic diarylethene derivative, 1,2-bis(2-methyl-5-(1- naphthyl)-3-thienyl)perfluorocyclopentene (1o), and perfluoronaphthalene (FN) has been examined. The crystal of 1o•FN with the size of 1-5 mm in length exhibits reversible bending motion upon alternate irradiation with ultraviolet (UV) and visible light. The reversible bending could be repeated over 250 times. In situ X-ray crystallographic analysis revealed that the deformation of the crystal is due to the elongation of the b-axis of the unit cell, which corresponds to the long axis of the plate crystal, induced by the shape change of component diarylethene molecules upon photocyclization. The bending motion was observed even at 4.7 K, and dynamic measurement of the bending proved that the anisotropic expansion of the crystal takes place in the microsecond time scale at the low temperature. Molecular crystal cantilevers made of 1o•FN can lift metal balls, the weight of which is 200-600 times heavier than the weight of the crystal, upon UV irradiation. The maximum stress generated by UV irradiation was estimated to be 44 MPa, which is 100 times larger than that of muscles (∼0.3 MPa) and comparable to that of piezoelectric crystals, such as lead zirconate titanate (PZT) (∼50 MPa). © 2010 American Chemical Society.


Nakagawa S.,RIKEN | Nakagawa S.,Japan Science and Technology Agency | Prasanth K.V.,University of Illinois at Urbana - Champaign
Trends in Cell Biology | Year: 2011

X-chromosome inactivation has long served as an experimental model system for understanding the epigenetic regulation of gene expression. Central to this phenomenon is the long, non-coding RNA Xist that is specifically expressed from the inactive X chromosome and spreads along the entire length of the chromosome in cis. Recently, two of the proteins originally identified as components of the nuclear scaffold/matrix (S/MAR-associated proteins) have been shown to control the principal features of X-chromosome inactivation; specifically, context-dependent competency and the chromosome-wide association of Xist RNA. These findings implicate the involvement of nuclear S/MAR-associated proteins in the organization of epigenetic machinery. Here, we describe a model for the functional role of S/MAR-associated proteins in the regulation of key epigenetic processes. © 2011 Elsevier Ltd.


Toyoda T.,University of Electro - Communications | Shen Q.,University of Electro - Communications | Shen Q.,Japan Science and Technology Agency
Journal of Physical Chemistry Letters | Year: 2012

There is a great deal of interest in dye-sensitized solar cells (DSCs) fabricated with nanostructured TiO 2 electrodes. Many different dye molecules have been designed and synthesized to achieve high photovoltaic conversion efficiency. Recently, as an alternative to organic dyes, semiconductor quantum dots (QDs) have been studied for their light-harvesting capability compared with other sensitizers. Accordingly, an attractive configuration to exploit these fascinating properties of semiconductor QDs is the quantum-dot-sensitized solar cell (QDSC) due to their high photoactivity, process realization, and low cost of production. The morphology of TiO 2 electrodes included with surface orientation is important for satisfactory assembly of QDSCs in order to improve the efficiency. Breakthroughs allowing an increase in efficiency will advance on two areas of electrode morphology control, namely, (A) TiO 2 nanotube electrodes and (B) inverse opal TiO 2 electrodes. © 2012 American Chemical Society.


Kijima T.E.,Graduate University for Advanced Studies | Innan H.,Graduate University for Advanced Studies | Innan H.,Japan Science and Technology Agency
Molecular Biology and Evolution | Year: 2010

It has been proposed that the insertion time of a long terminal repeat (LTR) retrotransposon can be estimated by the divergence between the two LTRs at the both ends because their sequences were identical at the insertion event. This method is based on the assumption that the two LTRs accumulate point mutations independently; therefore, the divergence reflects the time since the insertion event. However, if gene conversion occurs between LTRs, the nucleotide divergence will be much smaller than expected with the assumption of the independent accumulation of point mutations. To examine this assumption, we investigated the extent of gene conversion between LTRs by applying a comparative genomic approach to primates (humans and rhesus macaques) and rodents (mice and rats). We found that gene conversion plays a significant role in the molecular evolution of LTRs in primates and rodents, but the extent is quite different. In rodents, most LTRs are subject to extensive gene conversion that reduces the divergence, so that the divergence-based method results in a serious underestimation of the insertion time. In primates, this effect is limited to a small proportion of LTRs. The most likely explanation of the difference involves the minimum length of the interacting sequence (minimal efficient processing segment [MEPS]) for interlocus gene conversion. An empirical estimate of MEPS in human is 300-500 bp, which exceeds the length of most of the analyzed LTRs. In contrast, MEPS for mice should be much smaller. Thus, MEPS can be an important factor to determine the susceptibility of LTRs to gene conversion, although there are many other factors involved. It is concluded that the divergence method to estimate the insertion time should be applied with special caution because at least some LTRs undergo gene conversion. © The Author 2009.


Wang W.-H.,Dalian University of Technology | Himeda Y.,Japan National Institute of Advanced Industrial Science and Technology | Himeda Y.,Japan Science and Technology Agency | Muckerman J.T.,Brookhaven National Laboratory | And 2 more authors.
Chemical Reviews | Year: 2015

A study was conducted to show CO2 hydrogenation as an alternative method for so-called artificial photosynthesis to produce fuels, such as formate/formic acid and methanol, with good selectivity and high efficiency. For CO2 hydrogenation, an inexpensive and green source of H2 is needed in contrast to the industrial reforming of natural gas. To obtain formic acid for the regeneration of H2 or use in fuel cells, additional acid must be added to neutralize the formate. As an alternative to the use of a base in CO2 hydrogenation, a Lewis acid is a useful additive for H2 release from formic acid. To reduce the cost, catalysis with earth-abundant metals such as Fe or Co is highly desirable, and considerable progress has been achieved. Innovative ligands with functional groups are capable of gaining or losing one or more protons, and photoresponsive ligands capable of undergoing a useful change in properties upon irradiation. Kinetic isotope effects and computational studies provide clear evidence for the involvement of a water molecule in the rate-determining heterolysis of H2 in CO2 hydrogenation that accelerates proton transfer through the formation of a water bridge. Solution pH alters the rate-determining step for H2 generation from formic acid with these bioinspired complexes.


Patent
Japan Science, Technology Agency and University of Fukui | Date: 2010-12-22

The mold assembly for magnesium alloys comprises a mold and/or a core, each formed of an air permeable material. The air permeable material is any one or any combination of a network, a sheet having multiple holes, and cloth. The network, the sheet or the cloth is any one or any combination of a metal, a chemical fiber, and a ceramic material. The invention also provides a casting method for magnesium alloys, which uses that mold assembly.


News Article | November 4, 2016
Site: www.newsmaker.com.au

Tsukuba, Japan - Scientists use fragments of RNA and DNA with specific nucleotide sequences to identify others with complementary sequences, indicating, for example, the presence of a specific kind of virus. Researchers in Japan have recently improved the existing probing techniques using a cyanine dye called Cy3. RNA and DNA "probes" are conventionally made using fragments of strands that have nucleotide sequences on either end that complement each other. A fluorescent chemical compound, called a "fluorophore", is added to one end of the probe and a "quencher" is added at the other. In the absence of its complementary "target", the single-stranded probe comes together in a hair-pin-like manner, with the complementary sequences at either end of the strand binding together, bringing the fluorophore and quencher close to each other and turning down, or "quenching", the fluorophore's fluorescence. However, when a probe is present in a sample with its complementary target RNA, the probe strand "opens up" to combine with its target, allowing its detection when light is shone and the fluorophore fluoresces. This method is widely used, but the response of the hair-pin-like probe to its targets is relatively slow. A team of researchers from Nagoya University and the Japan Science and Technology Agency developed a new probe design based on Cy3 as the fluorophore. Cy3 and the quencher (nitro methyl red) were incorporated into either end of a linear strand that lacked the self-complementary sequences found in conventional probes. Even so, Cy3 and the quencher were drawn to each other spontaneously to form a highly stable complex in the absence of a target, quenching Cy3's fluorescence. In the presence of a complementary target, a strong fluorescence response was observed, which was ten times faster compared to conventional techniques. The team optimized its design by incorporating two Cy3 residues separated by two nucleotide bases on one end of the probe strand, and two nitro methyl red residues separated by two nucleotide bases on the other end. This optimized design detected RNA with high efficiency and sensitivity. Because Cy3 and nitro methyl red are able to combine in the probe, quenching fluorescence, without the need for self-complementary pairing, "this strategy will be applicable to the design of peptide-based probes," conclude the researchers in their paper published in the journal Science and Technology of Advanced Materials. Peptide probes are chains of linked amino acids that can be designed to bind with specific cell receptors, making them useful in tumor receptor imaging, for example. For further information please contact:  Professor Hiromu Kashida, * Professor Hiroyuki Asanuma, Nagoya University - Graduate School of Engineering, * [email protected] Article information  Hiromu Kashida, Kazuhiro Morimoto, Hiroyuki Asanuma, "A stem-less probe using spontaneous pairing between Cy3 and quencher for RNA detection"  http://dx.doi.org/10.1080/14686996.2016.1182412 Science and Technology of Advanced Materials (STAM, http://www.tandfonline.com/toc/tsta20/current) is an international open access journal in materials science. The journal covers a broad spectrum of topics, including synthesis, processing, theoretical analysis and experimental characterization of materials. Emphasis is placed on the interdisciplinary nature of materials science and on issues at the forefront of the field, such as energy and environmental issues, as well as medical and bioengineering applications. For more information about STAM contact Mikiko Tanifuji Publishing Director Science and Technology of Advanced Materials E-mail: [email protected] Press release distributed by ResearchSEA for Science and Technology of Advanced Materials.


News Article | November 7, 2016
Site: www.sciencedaily.com

Cyanine dyes could improve the efficiency of molecular probes in identifying, for example, the presence of a virus or a tumor receptor. Scientists use fragments of RNA and DNA with specific nucleotide sequences to identify others with complementary sequences, indicating, for example, the presence of a specific kind of virus. Researchers in Japan have recently improved the existing probing techniques using a cyanine dye called Cy3. RNA and DNA "probes" are conventionally made using fragments of strands that have nucleotide sequences on either end that complement each other. A fluorescent chemical compound, called a "fluorophore," is added to one end of the probe and a "quencher" is added at the other. In the absence of its complementary "target," the single-stranded probe comes together in a hair-pin-like manner, with the complementary sequences at either end of the strand binding together, bringing the fluorophore and quencher close to each other and turning down, or "quenching," the fluorophore's fluorescence. However, when a probe is present in a sample with its complementary target RNA, the probe strand "opens up" to combine with its target, allowing its detection when light is shone and the fluorophore fluoresces. This method is widely used, but the response of the hair-pin-like probe to its targets is relatively slow. A team of researchers from Nagoya University and the Japan Science and Technology Agency developed a new probe design based on Cy3 as the fluorophore. Cy3 and the quencher (nitro methyl red) were incorporated into either end of a linear strand that lacked the self-complementary sequences found in conventional probes. Even so, Cy3 and the quencher were drawn to each other spontaneously to form a highly stable complex in the absence of a target, quenching Cy3's fluorescence. In the presence of a complementary target, a strong fluorescence response was observed, which was ten times faster compared to conventional techniques. The team optimized its design by incorporating two Cy3 residues separated by two nucleotide bases on one end of the probe strand, and two nitro methyl red residues separated by two nucleotide bases on the other end. This optimized design detected RNA with high efficiency and sensitivity. Because Cy3 and nitro methyl red are able to combine in the probe, quenching fluorescence, without the need for self-complementary pairing, "this strategy will be applicable to the design of peptide-based probes," conclude the researchers in their paper published in the journal Science and Technology of Advanced Materials. Peptide probes are chains of linked amino acids that can be designed to bind with specific cell receptors, making them useful in tumor receptor imaging, for example.


News Article | August 30, 2016
Site: www.cemag.us

Simple cements are everywhere in construction, but researchers want to create novel construction materials to build smarter infrastructure. The cement known as mayenite is one smart material — it can be turned from an insulator to a transparent conductor and back. Other unique properties of this material make it suitable for industrial production of chemicals such as ammonia and for use as semiconductors in flat panel displays. The secret behind mayenite's magic is a tiny change in its chemical composition, but researchers hadn't been sure why the change had such a big effect on the material, also known as C12A7. In new work, researchers show how C12A7 components called electron anions help to transform crystalline C12A7 into semiconducting glass. The study, published recently in Proceedings of the National Academy of Sciences, uses computer modeling that zooms in at the electron level along with lab experiments. They showed how the small change in composition results in dramatic changes of the glass properties and, potentially, allows for greater control of the glass formation process. "We want to get rid of the indium and gallium currently used in most flat panel displays," says materials scientist Peter Sushko of the Department of Energy's Pacific Northwest National Laboratory. "This research is leading us toward replacing them with abundant non-toxic elements such as calcium and aluminum." More than a decade ago, materials scientist Hideo Hosono at the Tokyo Institute of Technology and colleagues plucked an oxygen atom from a crystal of C12A7 oxide, which turned the transparent insulating material into a transparent conductor. This switch is rare because the conducting material is transparent: Most conductors are not transparent (think metals) and most transparent materials are not conductive (think window glass). Back in the crystal, C12A7 oxide's departing oxygen leaves behind a couple electrons and creates a material known as an electride. This electride is remarkably stable in air, water, and ambient temperatures. Most electrides fall apart in these conditions. Because of this stability, materials scientists want to harness the structure and properties of C12A7 electride. Unfortunately, its crystalline nature is not suitable for large-scale industrial processes, so they needed to make a glass equivalent of C12A7 electride. And several years ago, they did. Hosono and colleagues converted crystalline C12A7 electride into glass. The glass shares many properties of the crystalline electride, including the remarkable stability. Crystals are neat and tidy, like apples and oranges arranged orderly in a box, but glasses are unordered and messy, like that same fruit in a plastic grocery bag. Researchers make glass by melting a crystal and cooling the liquid in such a way that the ordered crystal doesn't reform. With C12A7, the electride forms a glass at a temperature about 200 degrees lower than the oxide does. This temperature — when the atoms stop flowing as a liquid and freeze in place — is known as the glass transition temperature. Controlling the glass transition temperature allows researchers to control certain properties of the material. For example, how car tires wear down and perform in bad weather depends on the glass transition temperature of the rubber they're made from. Sushko, his PNNL colleague Lewis Johnson, Hosono and others at Tokyo Tech wanted to determine why the electride's glass transition temperature was so much lower than the oxide's. They suspected components of the electride known as electron anions were responsible. Electron anions are essentially freely moving electrons in place of the much-larger negatively charged oxygen atoms that urge the oxide to form a tidy crystal. The team simulated Hosono's lab experiments using molecular dynamics software that could capture the movement of both the atoms and the electron anions in both the melted material and glass. The team found that that the negatively-charged electron anions paired up between positively charged aluminum or calcium atoms, replacing the negatively charged oxygen atoms that would typically be found between the metals. The bonds that the electron anions formed between the metal atoms were weaker than bonds between metal and oxygen atoms. These weak links could also move rapidly through the material. This movement allowed a small number of electron anions to have a greater effect on the glass transition temperature than much larger quantities of minerals typically used as additives in glasses. To rule out other factors as the impetus for the lower transition temperature — such as the electrical charge or change in oxygen atoms — the researchers simulated a material with the same composition as the C12A7 electride but with the electrons spread evenly through the material instead of packed in as electron anions. In this simulation, the glass transition temperature was no different than C12A7 oxide's. This result confirmed that the network of weak links formed by the electron anions was responsible for changes to the glass transition temperature. According to the scientists, electron anions form a new type of weak link that can affect the conditions under which a material can form a glass. They join the ranks of typical additives that disrupt the ability of the material to form long chains of atoms, such as fluoride, or form weak, randomly oriented bonds between atoms of opposite charge, such as sodium. The work suggests researchers might be able to control the transition temperature by changing the amount of electron anions they use. "This work shows us not just how a glass forms," says PNNL's Johnson, "but also gives us a new tool for how to control it." This work was supported by the Japan Science and Technology Agency and PNNL.


News Article | November 21, 2016
Site: www.cemag.us

Solar energy could provide a renewable, sustainable source of power for our daily needs. However, even the most state-of-the-art solar cells struggle to achieve energy conversion efficiency of higher than 30 percent. While current solar-powered water heaters fare better in terms of energy efficiency, there are still improvements to be made if the systems are to be used more widely. One potential candidate for inclusion in solar water heaters is “nanofluid” — that is, a liquid containing specially-designed nanoparticles that are capable of absorbing sunlight and transforming it into thermal energy in order to heat water directly. Now, Satoshi Ishii and his co-workers at the International Center for Materials Nanoarchitectonics (WPI-MANA) and the Japan Science and Technology Agency have developed a new nanofluid containing titanium nitride (TiN) nanoparticles, which demonstrates high efficiency in heating water and generating water vapor. The team analytically studied the optical absorption efficiency of a TiN nanoparticle and found that it has a broad and strong absorption peak thanks to lossy plasmonic resonances. Surprisingly, the sunlight absorption efficiency of a TiN nanoparticle outperforms that of a carbon nanoparticle and a gold nanoparticle. They then exposed each nanofluid to sunlight and measured its ability to heat pure water. The TiN nanofluid had the highest water heating properties, stemming from the resonant sunlight absorption. It also generated more vapor than its carbon-based counterpart. The efficiency of the TiN nanofluid reached nearly 90 percent. Crucially, the TiN particles were not consumed during the process, meaning a TiN-based heating system could essentially be self-sustaining over time. TiN nanofluids show great promise in solar heat applications, with high potential for use in everyday appliances such as showers. The new design could even contribute to methods for decontaminating water through vaporization.


News Article | December 11, 2015
Site: phys.org

Kampo doctors frequently use palpation to understand the body's condition and signs of illnesses. Because this process is based on the doctor's own knowledge and experience, it has been difficult to produce data on the process that would help other doctors objectively understand the basis for a diagnosis. In this newly developed technology, a flexible, thin-film pressure sensor has been made that does not cause any loss of sensitivity when used in an examination. Sensors are fitted to the finger pads and measure sensory information as pressure data when the doctor touches the patient during a palpation. Tying this to the track that the doctor's hands follow quantifies the touches so that they can be recorded as data. This will make it possible to amass data on palpations by Kampo doctors and look at them objectively to help doctors with future diagnoses, and will contribute to the discovery of sub-health. Part of this project was developed under Japan's Ministry of Education, Culture, Sports, Science, and Technology's The Center of Innovation (COI) Program (COI Stream), promoted by the Japan Science and Technology Agency, under the program title "Research and Development on Mibyou Control System Using Safe and High Quality Kampo Medicine and Information and Communication Technology." This development is being presented at the IEEE.International Conference on Sensing Technology 2015 (ICST 2015), which opened December 8 in Auckland, New Zealand. An important aspect of Kampo is to promote a long, healthy life in which everyday activities are not restricted by discovering conditions that may lead to illness before they actually manifest as illness, and deal with them at that level. Kampo doctors can detect sub-health conditions—that would not be diagnosed as illnesses in Western medicine - before symptoms appear. But the diagnostic standards in Kampo—which are based on interviews, taking pulses, examining tongues, and palpating the abdomen—often rely on the practitioner's subjective impressions, and have never been defined. In Kampo, palpation in which the patient's abdomen is directly touched, is an important technique for judging the patient's condition and signs of disease, but as the final analysis is based on the practitioner's experience and knowledge, there needs to be a way to formalize diagnostic standards and express them objectively in order to pass that information along and cultivate the skills of other doctors. Objectively capturing a doctor's palpations as data using ICT would require a sensitive, flexible sensor that made neither the doctor nor patient feel uncomfortable, an important feature considered during development. Fujitsu Limited, Fujitsu Laboratories, and the Oriental Medicine Research Center together have developed a prototype of a system that can detect where the body is being palpated and can capture firmness data using a glove-type touch sensor that does not diminish the doctor's sense of touch when palpating (Figure 2). Features of the technology are as follows. The pressure-sensing element is based on an induction film (electret), which has the property of separating positive and negative electric charges without an electrical field; taking advantage of a characteristic of these in which their internal electrical load changes when pressure is applied. Using this property, the partners developed a highly sensitive pressure sensor (Figure 3). A high-resistance film surrounds the pressure-sensing element to minimize charge leakage, and the voltage response continues from the moment that pressure is applied. An insulating material with a low dielectric constant minimizes the electrical capacity of the pressure-sensing element, which increases the voltage output in proportion to the applied pressure, resulting in better sensitivity. To capture sensory input when a doctor is palpating a patient without diminishing the doctor's sense of touch, the partners developed a thinner membrane using polymer film(3), producing a membrane with a thickness of 100 to 300-micrometers with improved flexibility. These improvements obviate the need for a driver power source in the pressure-sensing elements that contact the patient, resulting in good sensitivity and improved safety. The partners built a system that tracks the movement of the doctor's hand with an accuracy of approximately 0.2-mm, using reflective markers attached to the fingertips of the glove and an infrared camera that monitors those markers. The system captures hand positions every 10-milliseconds and combines that data with the data from the pressure sensors to accurately synchronize and record pressure and palpation location. The prototype touch-data collection system was used to capture touch-data in a mock examination experiment at the Oriental Medicine Research Center (Figure 4). This shows linear responsiveness to applied pressure, producing 120-mV per 1-kPa of pressure on average. This corresponds to an output of 120-mV when applying 0.1-gram of force over a sensing surface area of 1-mm2. The prototype circuit produced approximately 10-mV of noise continuously, but because the signal from hand pressure is more than 10 times greater, this was found to permit sufficient responsiveness to minor changes in palpation pressure. This was confirmed to capture numerical data from the sensor with no significant difference from the actual palpation. Fujitsu Limited, Fujitsu Laboratories, and the Oriental Medicine Research Center are considering ways to further improve sensor sensitivity and to expand sensor coverage to the palm of the hand, and look forward to assisting doctors with their palpations while amassing data from palpations by Kampo practitioners using this technology to make it objectively assessable.


News Article | November 22, 2016
Site: www.eurekalert.org

Japanese researchers have found that genes respond differently to the amount and rate of secretions of insulin, a hormone whose malfunction can lead to obesity and diabetes. Some genes express themselves quickly when stimulated by high levels of insulin, while others pick up on low sustained levels of the hormone, and repress themselves instead. Insulin plays an important role in lowering glucose to regulate blood sugar. The body sustains low-dose levels of insulin at all times, while secretions spike temporarily after meals, creating wavelike fluctuations in the amount of insulin that is secreted and circulating in the bloodstream. The hormone is also involved in metabolism and other cellular and biological processes by regulating gene expression; but the mechanism by which the amount and temporal patterns of insulin secretions--caused by eating and longer periods of fasting between meals--control the manifestation or repression of genes was not clear. The team led by University of Tokyo researchers extracted wavelike patterns representing temporal changes in genetic expression, for all genes responsive to insulin stimulation; they worked with cultured cells derived from malignant tumors in rat livers, called FAO cells, that were injected with insulin and used RNA sequencing to measure gene expression. The scientists found that 278 genes responded to insulin, referring to them as insulin-responsive genes, or IRGs. From these, they identified over 50 genes that are involved in important processes, such as cell metabolism, cell growth, and cell division. Further experimental analyses and mathematical modeling revealed that the genes responded differently to variations in insulin levels and temporal patterns: IRGs whose gene expression increased with insulin stimulation responded rapidly to high doses, while IRGs whose gene expression decreased with the stimulation reacted to low doses, at a slower response rate. Furthermore, the researchers confirmed that the response of a subset of IRGs in rat livers, when injected with insulin, dovetailed with the results involving cultured cells. "Our study shows how temporal changes and doses of insulin control gene expression," says University of Tokyo Professor Shinya Kuroda, a coauthor. "The method we used can be applied to all biological phenomena for which wavelike patterns representing temporal changes can be obtained," says Kuroda. He continues, "One of the potential uses of this approach is to design therapies using drugs whose release rate can be controlled to effectively treat diseases like type 2 diabetes." Takanori Sano, Kentaro Kawata, Satoshi Ohno, Katsuyuki Yugi, Hiroaki Kakuda, Hiroyuki Kubota, Shinsuke Uda, Masashi Fujii, Katsuyuki Kunida, Daisuke Hoshino, Atsushi Hatano, Yuki Ito, Miharu Sato, Yutaka Suzuki, and Shinya Kuroda, "Selective control of up-regulated and down-regulated genes by temporal patterns and doses of insulin," Science Signaling Professor Shinya Kuroda Department of Biological Sciences, Graduate School of Science, University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan Tel: +81-3-5841-4697 (Kuroda), +81-3-5841-4699 (Lab.) Fax: +81-3-5841-4698 Email: skuroda@bs.s.u-tokyo.ac.jp. This work was supported by the Creation of Fundamental Technologies for Understanding and Control of Biosystem Dynamics, CREST from the Japan Science and Technology Agency (JST), by the Japan Diabetes Foundation, and by the Ono Medical Research Foundation. Katsuyuki Yugi was funded by the Japan Society for the Promotion of Science (JSPS) [JSPS Grants-in-Aid for Scientific Research (KAKENHI) grant no. JP15H05582] and by the "Creation of Innovative Technology for Medical Applications Based on the Global Analyses and Regulation of Disease-Related Metabolites," PRESTO from JST. Hiroyuki Kubota was funded by "Elucidation and regulation in the dynamic maintenance and transfiguration of homeostasis in living body," PRESTO from JST. The University of Tokyo is Japan's leading university and one of the world's top research universities. The vast research output of some 6,000 researchers is published in the world's top journals across the arts and sciences. Our vibrant student body of around 15,000 undergraduate and 15,000 graduate students includes over 2,000 international students. Find out more at http://www. or follow us on Twitter at @UTokyo_News_en.


News Article | November 28, 2016
Site: www.eurekalert.org

Scientists at the Okinawa Institute of Science and Technology Graduate University (OIST) have been awarded a grant from the Japan Science and Technology Agency (JST) to turn their energy-producing waste water treatment technology into a startup company. The technology, created by researchers in OIST's Biological Systems Unit, uses bacteria to clean environment-polluting waste water, whilst generating electricity in the process. These so-called microbial fuel cells consist of a partitioned chamber with electrodes on either side. One electrode is coated in special microbes that release electrons when they break down organic waste in the absence of oxygen. These electrons flow through a circuit to reach the other electrode where electrical current is extracted as power. Unlike traditional waste water treatment methods that consume a lot of energy, microbial fuel cells can produce more energy than they consume, making them a viable source of sustainable energy. "Our product is very applicable for local Okinawan industries that generate a lot of organic waste water," says, David Simpson from the Biological Systems Unit who has played a key role in the development of this technology. One such industry is the production of awamori, an alcoholic spirit made from rice that is unique to Okinawa. Waste water containing bits of rice, as well as rice mold used to start the fermentation process and other waste products is left behind after the awamori has been distilled. OIST's researchers have been able to use their technology to clean this waste water so that it can be safely released into the environment. Following the success of a pilot study in the Mizuho Shuzo awamori distillery in the Okinawan city of Naha, in which this technology was implemented over a three-year period, The Program for Creating STart-ups from Advanced Research and Technology (START) grant* from JST will enable the project to be scaled up for enhanced industrial applications. "This project is not only focused on environmental issues, but will contribute to the sustainable development of Okinawa," says Professor Igor Goryanin, head of OIST's Biological Systems Unit. The ultimate goal of the project is to create a product that harnesses the energy produced by the water-cleaning bacteria in a cost effective way and apply it to the Mizuho Shuzo distillery in Okinawa, making it self-sufficient for treating its own waste by the end of 2018. The combinations of bacteria could also be tailored for specific types of waste water meaning that this technology could be implemented in local pig farms and tofu factories, in addition to more international industries looking to clean waste water at the same time as generating sustainable energy. "This technology is low maintenance and the ease of use benefits can be applied to developing countries and the improvement of water sources around the world," says Simpson. OIST researchers are partnered in this grant with Bio-Sight Capital, a venture capital firm that will help guide the commercialization of the microbial fuel cells for industry. Given the success of a former collaboration between Bio-Sight Capital and OIST that resulted in the launch of OIST's first startup company, Okinawa Protein Tomography Ltd., researchers in the Biological Systems Unit are hopeful that this grant-supported partnership will enable microbial fuel cells technology to break into a commercial sphere, both nationally and internationally. Dr. Viacheslav Fedorovich , who is also a member of the Biological Systems Unit, is very excited about this opportunity and thinks that it is right time for commercialization of the technology in Japan. *The Program for Creating STart-ups from Advanced Research and Technology (START Program) assigns project promoter units who have commercialization knowhow. START Program is aiming at developing business/intellectual property (IP) strategies for technology seeds in universities that are risky but have great potential and commercializing them, by combining public funding and private sector commercialization knowhow even before start-ups are established. In this way, START Program is aspiring for making research achievements of universities and national research and development agency widely utilized in society and creating a Japanese-style innovation model that will serve as a sustainable mechanism.


News Article | September 21, 2016
Site: www.nature.com

Last year, Christina Quasney was close to giving up. A biochemistry major at the University of Maryland, Baltimore County, Quasney's background was anything but privileged. Her father runs a small car-repair shop in the tiny community of Millersville, Maryland, and she was the first person in her immediate family to attend university. At the age of 25, she had already spent years struggling to make time both for her classes and the jobs she took to pay for them, yet was still far from finishing her degree. “I started to feel like it was time to stop fighting this losing battle and move on with my life,” she says. Quasney's frustrations will sound familiar to millions of students around the world. Researchers like to think that nothing matters in science except the quality of people's work. But the reality is that wealth and background matter a lot. Too few students from disadvantaged backgrounds make it into science, and those who do often find that they are ill-prepared owing to low-quality early education. Few countries collect detailed data on socioeconomic status, but the available numbers consistently show that nations are wasting the talents of underprivileged youth who might otherwise be tackling challenges in health, energy, pollution, climate change and a host of other societal issues. And it's clear that the universal issue of class is far from universal in the way it plays out. Here, Nature looks at eight countries around the world, and their efforts to battle the many problems of class in science. United States: How the classroom reflects class divide China: Low pay powers brain drain United Kingdom: The paths not taken Japan: Deepening divisions Brazil: Progressive policy pays off India: Barriers of language and caste Kenya: Easy access but limited prospects Russia: Positive policy, poor productivity By Jane J. Lee Quasney is lucky by global standards. She lives in an exceedingly rich country that is brimming with educational opportunities and jobs. Yet for students who share her struggles to make ends meet, the US higher-education system can pose one obstacle after another. “It starts in high school,” says Andrew Campbell, dean of the graduate school at Brown University in Providence, Rhode Island. Government-supported early education is funded mainly at the state and local level, he notes, and because science courses are the most expensive per student, few schools in the relatively poor districts can afford to offer many of them. Students from these districts therefore end up being less prepared for university-level science than are their wealthier peers, many of whom attended well-appointed private schools. That also puts the students at a disadvantage in the fiercely competitive applications process: only about 40% of high-school graduates in the lowest-income bracket enrolled in a university in 2013, versus about 68% of those born to families with the highest incomes. The students who do get in then have to find a way to pay the increasingly steep cost of university. Between 2003 and 2013, undergraduate tuition, fees, room and board rose by an average of 34% at state-supported institutions, and by 25% at private institutions, after adjusting for inflation. The bill at a top university can easily surpass US$60,000 per year. Many students are at least partly supported by their parents, and can also take advantage of scholarships, grants and federal financial aid. Many, like Quasney, work part time. Nonetheless, some 61% of US students earning bachelor's degrees graduate with some debt — US$26,900, on average. For those who go on to graduate programmes, tuition is usually paid for by a combination of grants and teaching positions. But if graduate students have to worry about repaying student loans, that can dissuade them from continuing with their scientific training. Several initiatives are under way around the country to ease the way for science students from disadvantaged backgrounds, among them is the $14-million INCLUDES programme announced earlier this year by the US National Science Foundation. But for students such as Quasney, staying in science can still be a matter of luck. One evening last year, she says, Michael Summers, a structural biologist at the university, happened to have dinner at the restaurant where she was hosting and waiting tables. That chance encounter led Quasney to join Summers' laboratory in January, and it was a revelation. Before, she had felt that some of her professors had forgotten what it was like to be a struggling student. Summers' lab is the exact opposite, she says. “There's no judgements and he doesn't discriminate.” Her experiences have helped her to understand what she can expect when she applies to graduate school and pursues a career in research. “I'm gonna go for it,” she says. “Go big or go home.” By David Cyranoski It is no accident that China currently produces more science PhDs than any country in the world. To combat large-scale poverty, especially in the interior provinces, the communist government in Beijing is trying to make education equally available to everyone. To help the poor, for example, Beijing sets tuition fees low and forbids raising them. Just 5,000 yuan (US$750) per year is enough for entry into premier institutions such as Tsinghua University in Beijing. And for those unable to come up with that sum, the country has national scholarship programmes, including tax-free loans and free admission. Meanwhile, to help integrate China's 55 ethnic minorities, which are also often poor, most provinces give bonus points to minority students who take the Gaokao: a university entrance examination that is the most important threshold to pass on the way to an academic career. A quota system ensures that students from remote regions such as Xinjiang and Tibet are represented at elite schools. China even has 12 universities that are dedicated to minorities. Beneath the surface, however, the reality of Chinese science often falls short of its egalitarian ideals. Children of senior government leaders and private business owners account for a disproportionate share of enrolment in the top universities. And students hesitate to take on the work-intensive career of a scientist when easier, and usually more lucrative, careers await them in business. According to Hepeng Jia, a journalist who writes about science-policy issues in China, this is especially true for good students from rich families. As a result, says Jia, scientists usually come from poorer families, get less support from home and work under a heavier financial burden. The situation is exacerbated by the low salaries, he says. The average across all scientific ranks is just 6,000 yuan per month, or about one-fifth of the salary of a newly hired US faculty member. Things are especially tough for postdoctoral researchers or junior-level researchers “who can hardly feed their families if working in bigger cities”, says Jia. This leads many scientists to use part of their grants for personal expenses. That forces them to make ends meet by applying for more grants, which requires them to get involved in many different projects and publish numerous papers, which in turn makes it hard to maintain the quality of their work. Many Chinese researchers escape that trap by seeking positions overseas. Thousands of postdoctoral researchers will go abroad in 2016 with funding from the China Scholarship Council, and many more will find sponsors abroad to fund them. But China has also been able to lure some of the most prominent of these researchers back home. Cao Kai, a researcher at the Science and Technology Talent Center of the science ministry in Beijing, released a survey in April that found one such returning scientist was rewarded with a stunningly high annual salary of 800,000 yuan. But that is not the norm, Kai says. It was just one extreme case he and his colleagues raised to convince “the government to raise the salary of professors at public universities”. That, he says, would go a long way to attracting and retaining talent in science, regardless of social background. By Elizabeth Gibney For the most part, science in the United Kingdom is egalitarian — for those who have already made it their career. A 2016 study found that, unlike in law or finance, researchers from lower-income backgrounds are paid no less than their more advantaged peers (D. Laurison and S. Friedman Am. Soc. Rev. 81, 668–695; 2016). But getting into science is different. The same study found that only 15% of scientists come from working-class households, which comprise 35% of the general population (see 'Elite careers'). Another found that, over the past 25 years, 44% of UK-born Nobel-prizewinning scientists had gone to fee-paying schools, which educate 7% of the UK population (P. Kirby Leading People 2016 The Sutton Trust, 2016). “There's a class barrier to the professions,” says Katherine Mathieson, chief executive of the British Science Association, “but it's more extreme for science.” One hurdle is aspirational. In an ongoing, 10-year study, a group from King's College London found that most English 10–14 year olds find science interesting. But those from working-class backgrounds rarely saw it as a career — perhaps because they seldom encountered people in science-related jobs (ASPIRES: Young People's Science and Career Aspirations, Age 10–14 King's College London, 2013). To tackle this, the King's team is working with London schools on a pilot programme to show children aged 11 to 15 how science fits into everyday life — by examining the chemicals in food, for example — and how science skills are relevant in a range of jobs. Early results are promising, and the team plans to expand the programme next year. Another barrier could be that UK students who are interested in a science career often need to abandon other subjects at the age of 16. “People from lower-income backgrounds who are unaware of the range of possible science careers might see it as a high-risk gamble,” says Mathieson. A third issue is the effect of a sudden trebling of annual university fees to £9,000 (US$12,000) in 2012. “I suspect that fees could be a massive deterrent to those who grow up in families that have to worry about the basic level of income,” says Mathieson. The danger, she adds, is that a failure to represent all backgrounds will not only squander talent, but increasingly isolate science from society. That disconnect was apparent in the Brexit referendum in June, when more than half of the public voted to leave the European Union, compared with around one in ten researchers. “That diverging world view is a real problem,” says Mathieson, “both for the quality of research and for scientists' place in society.” By David Cyranoski In Japan, inequalities in wealth and status do not reach the extremes found in China and India. Nonetheless, graduate education and academic research have become less attractive options over the past decade, especially for the underprivileged. Some warn that this could make research a preserve of the wealthy — with grave social costs.“It is an emerging issue in Japan,” says Yuko Ito, who researches science policy at the Japan Science and Technology Agency in Tokyo, a major science funder. A big part of the problem is the rise in tuition fees: even at the relatively inexpensive national universities, the ¥86,000 (US$840) in entrance and first-year tuition fees students paid in 1975 would make little dent in the ¥817,800 they've been paying since 2005. In addition, thanks to Japan's long economic contraction, parents are chipping in 19% less for living costs on average than they did a decade ago. This leaves students increasingly dependent on 'scholarships' — which in Japan are mainly loans that need to be paid back. Half of all graduate students have taken out loans, and one-quarter owe more than ¥5 million. “Many students just can't come up with the tuition and living costs to become researchers,” says Koichi Sumikura, a professor of science policy at the National Graduate Institute for Policy Studies in Tokyo. Even for those who make it through university on loans, jobs that would make the debt worthwhile are far from guaranteed. In their prime years, between the ages of 30 and 60, one-third of university graduates earns less than ¥3 million per year. “In these conditions,” says Ito, “one would hesitate to follow an academic career.” The social divide in higher education already shows. A crucial step to becoming a researcher is to enter a powerful institution such as the University of Tokyo, where the average income of a student's family is twice the national average. “If this situation continues,” Ito says, “science will become something that only the rich will hold an interest in, and research will grow distant from solving current social problems.” The government has taken stock of the issue. A government plan for 'investment in the future', announced on 2 August, promises to increase funding for scholarships that need not be repaid as well as to boost the availability of tax-free student loans. But the government has yet to take up a more specific examination of the relationship between success as a researcher and economic factors, says Sumikura. “That will be an important topic in the future,” he says. By Jeff Tollefson In Brazil, inequalities in wealth are extreme by almost every measure — including education. The government-run schools are so bad that they are avoided by all but the poorest families. As recently as 2014, just 57% of the country's 19-year-olds had completed high school. And yet there are signs of progress, especially in science, technology, engineering and medicine. In 2011, for example, Brazil created Science Without Borders, a programme to send tens of thousands of high-achieving university and graduate students to study abroad. Because students from wealthier families have by far the best primary and secondary education, they might have been expected to dominate the selection process. But by the end of the first phase this year, more than half of the 73,353 participants had come from low-income families. “These statistics really caught us all by surprise,” says Carlos Nobre, a climate scientist who formerly headed of one of the public foundations that fund Science Without Borders. In São Paulo, meanwhile, the medical school at the prestigious University of Campinas (UNICAMP) gives preference to admitting gifted students from government-run schools. The programme started in 2004 after research suggested that out of those with similar test scores prior to admittance, predominantly poor government-school students tended to perform better at UNICAMP than did their counterparts from private schools. The former comprised 68% of this year's entering class. Carlos Henrique de Brito Cruz, who launched the UNICAMP initiative when he was the university rector, suspects that part of the answer is quite simple. “These students had more obstacles to overcome,” he says. “And when you put them in an environment where the obstacles are more or less the same, they tend to realize more of their potential.” Brazil may also be seeing the fruits of the government's effort to improve scientific literacy and push more students into science careers, which gained momentum after the inauguration of Luiz Inácio Lula da Silva as president in 2003. A division at the federal Ministry of Science, Technology and Innovation focuses entirely on 'social inclusion', with programmes to improve public schools and promote research in fields that affect local communities, such as nutrition and sustainability. The poor quality of secondary education remains a substantial problem that could take a generation or more to address, experts say. Nonetheless, existing initiatives could be boosting the quality of government schools enough for ambitious students to excel, says Nobre. The next question, he says, is whether these students will be able to bolster innovation in Brazilian science. “Now that they are coming into the market, we will have to start evaluating very quickly what happened to these students.” By T. V. Padma Despite the renown of technology hubs such as Bangalore and universities such as the multicampus Indian Institute of Technology, vast numbers of talented students in India never get to realize their full potential owing to poor rural schools, language barriers and the caste system. Especially outside the cities, higher education — including science — largely remains a privilege of the rich, the politically powerful and the upper castes. India's national census does not collect data on caste, rural or gender representation in science, nor do the country's science departments. Nonetheless, says Gautam Desiraju, a chemist at the Indian Institute of Science in Bangalore, it is clear that rural Indian students are hampered by a lack of good science teachers and lab facilities, and are unaware of opportunities to enter mainstream science (see www.nature.com/indiascience). The barriers are even higher for rural girls, who are discouraged from pursuing higher studies or jobs, and for girls from poor urban families, who are expected to take jobs to contribute to their dowries. Many rural students are also hampered by their poor English, the language that schools often use to explain science. “Teachers from elite colleges and interview and selection committees are often biased against such students,” says immunologist Indira Nath, at the Indian National Science Academy in New Delhi. Caste — the hereditary class system of Hindu society — is officially not an issue. India's constitution and courts have mandated that up to half of the places in education and employment must be reserved for people from historically discriminated-against classes. However, a clause excludes several of India's top science centres from this requirement. And in reality there is an “unintentional, subtle or hidden discrimination against students from reserved categories, right from high school to college levels”, says Shri Krishna Joshi, a scientist emeritus at the National Physical Laboratory in New Delhi. Teachers do not encourage them as much as they do students from upper castes. As a result, he says, “poor students from reserved categories in turn often have psychological barriers and believe they cannot compete with the others”. Still, says Desiraju, there are signs of progress. For a long time, Indian officials assumed that all they had to do was set up centres of scientific excellence and the effects on education would simply trickle down to the masses. “But now,” he says, “agencies are beginning to adopt a more bottom-up approach” that seeks to find talented people at the lowest economic levels. At the University of Delhi South Campus, geneticist Tapasya Srivastava sees the effects of that shift. “Competitiveness for higher science education is increasing across all caste-based categories and gaps are dissolving,” she says. “Talented young researchers are getting admissions based on their merit alone and not because of the constitutional provision,” agrees Desiraju. But there is much still to be done, he says. “Finding the right talented girl or boy in a small town or village in India is often like finding a needle in a haystack.” In Kenya, where around 40% of the population lives on less than US$1.25 a day, class matters surprisingly little for who makes it into science. As one of Africa's fast-growing 'lion' economies, the country has seen university enrolment more than double since 2011, reaching more than 500,000 last year. The government subsidizes tuition fees for poor secondary-school students who get good grades in science, and there are loans available to help them with living expenses. At the postgraduate level, however, the lack of opportunities in Kenya means that many science hopefuls have to do part of their training abroad. “The problem for me wasn't getting into science, it was staying in,” says Anne Makena, a Kenyan from a lower-class background with an undergraduate degree in biochemistry from Moi University in Eldoret. She now has a Rhodes scholarship to finish her PhD in chemical biology at the University of Oxford, UK. For those staying at home, the surest path to a research career is to get a job with foreign-funded organizations such as the International Centre of Insect Physiology and Ecology (ICIPE) in Nairobi, or the partnership between the Kenya Medical Research Institute (KEMRI) and the UK Wellcome Trust. But competition is fierce, and it can take years to get accepted. This is when graduates from a poorer background are more likely to give up, says Makena. They are drawn by lucrative private-sector salaries and mindful of the need to contribute financially to their families, whereas wealthier students can afford to wait. Another source of uncertainty is Kenyan universities' struggle to secure enough operating funds from the government. The shortfall has led vice-chancellors in the country's public universities to propose up to a five-fold rise in tuition fees for resource-intensive courses, including science. If this happens and government subsidies do not keep pace, poorer students might forego science courses for cheaper degrees. That would be a pity, says Baldwyn Torto, head of behavioural and chemical ecology at ICIPE, because Kenyan students from modest backgrounds make excellent scientists in his experience. “You find kids from poorer families performing equally well, if not better, than kids from wealthier families,” he says. By Quirin Schiermeier Following the Soviet Union's collapse in 1991, Russia was quickly given over to untamed capitalism and increasing inequity. Yet the country retained its socialist ideals in education: even now, Russia produces a large share of its science students and researchers from low- and middle-income backgrounds. “There is a national consensus in Russia regarding the value of equal opportunities in education for the modernization of our country,” says Dmitry Peskov, who directs the young professionals division of the Moscow-based Agency for Strategic Initiatives, which promotes economic innovation in Russia. The country hosts some 3,000 universities and higher learning institutes, and about half of its secondary-school graduates go on to attend them. The average among all Organisation for Economic Co-operation and Development countries is about 35%. In peripheral regions such as the Urals or Siberia, where local governments are keen to develop scientific and engineering capacity, teachers identify talented students as early as ages 4 to 6. If they continue to show promise, they are encouraged to enrol at local universities, whose tuition-free programmes may focus on local needs such as agricultural technology. Children who demonstrate exceptional skills in science, art, sports or even chess may earn admission to the Sirius educational centre in Sochi on the Black Sea. This centre, backed by Russian president Vladimir Putin, was set up after the 2014 Winter Olympics to help Russia's most gifted youths develop their talent with support from leading scientists and professionals. Since December 2015, prospective students who succeed in local or national science competitions and maths Olympiads can also hope to secure a presidential grant worth 20,000 roubles (US$307) per month. These grants allow hundreds of students from lower social backgrounds to study at the nation's top universities on the sole condition that they will stay in Russia for at least five years after graduation. But despite such efforts, Russia's science output remains relatively low. One reason, Peskov says, is the Russian science community's isolation. For all their skills and social diversity, Russian researchers tend to speak poor English and are underrepresented in international meetings and collaborations. Uncertainty over the Russian government's future support of science adds to the problem. “Lucrative jobs in finance, business administration or industry are much more popular among well-trained young Russians than is a risky academic career,” he notes.


Home > Press > An Ultra-Bright and Highly Coherent Electron Source Developed to Improve the Performance of Electron-Beam Analytical Instrument Abstract: Researchers at the National Institute for Materials Science -- Han Zhang, Senior Researcher, Spin Characterization Group, and Jie Tang, Group Leader of the One-Dimensional Nanomaterials Group, Materials Processing Unit, and collaborators developed technology to fabricate lanthanum hexaboride (LaB6) single-crystal nanowires with clean surface, a promising cold field-emission electron source for electron microscopes and other devices, and thereby improved the performance and stability of the electron source. Furthermore, by installing the new electron source into a scanning electron microscope, they successfully obtained high-resolution images, demonstrating that the electron source can actually serve as a source of ultra-bright electron beams for electron microscopes. To increase the spatial resolution of electron microscopes, it is necessary to obtain ultra-bright and highly coherent electron beams by narrowly focusing a large amount of electrons emitted from an electron source. At present, high-resolution electron microscopes are equipped with needle-like tungsten as an electron source. To increase the spatial resolution of the microscope even higher, efforts had been made to develop a field emission electron source using LaB6, which emits electrons more easily than tungsten. However, the synthesis of nanowires -- a requirement for the development of a field emission electron source -- using LaB6 was challenging because this very hard material was difficult to handle. In collaboration with Dr. Lu-Chang Qin, a professor at the University of North Carolina at Chapel Hill in the United States, the research team succeeded in the fabrication of the electron source consisting of a LaB6 nanowire by employing chemical vapor deposition. Furthermore, the research team developed technology to clean the surface of the LaB6 nanowire, which led to the improvement in electron emission characteristics and stability of the electron source. The research team confirmed that the newly developed LaB6 nanowire electron source was capable of producing highly coherent electron beams, which were 100 times brighter and had an energy spread of two-thirds compared to the current tungsten electron source. The team also verified that, when the electron source was installed in a field-emission electron microscope, its electron current density was 1,000 times greater than the conventional electron sources and it lasted 5 hours of use without attenuation in the emission current. Moreover, the team actually observed samples using an electron microscope equipped with the LaB6 nanowire electron source, and obtained electron microscopy images with a resolution higher than the conventional standard level. The LaB6 nanowire electron source can be easily installed in devices by simply replacing the conventional tungsten electron gun (electron source) with it. In the future, the team plans to work on practical use and commercialization of the LaB6 nanowire electron source through joint research with industrial partners. This research was carried out as a follow-up to the research project “Development of Next-Generation Electron Microscope Using Nanostructure-Controlled LaB6” (Jie Tang, Principal Investigator) conducted in the framework of Japan Science and Technology Agency’s program “Development of Advanced Measurement and Analysis Systems,” which aimed at the acceleration of innovation through industry-academia cooperation. This study was published in the online version of British scientific journal Nature Nanotechnology on November 30, 2015 (local time). About National Institute for Materials Science (NIMS) Public research institution for materials science in Japan. For more information, please click Contacts: Press Office Jie Tang Leader of the One-Dimensional Nanomaterials Group, Materials Processing Unit, NIMS Tel: +81-29-859-2728 Email: tang.jie=nims.go.jp (Please replace “=” with (Regarding public relations) Public Relations Office National Institute for Materials Science 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047, JAPAN Tel: +81-29-859-2026, Fax: +81-29-859-2017 Email: pressrelease=ml.nims.go.jp (Please replace “=” with If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


Kobayashi T.,Japan Science and Technology Agency | Kobayashi T.,Ishikawa Prefectural University | Nishizawa N.K.,Ishikawa Prefectural University
Plant Science | Year: 2014

The transcription of genes involved in iron acquisition in plants is induced under iron deficiency, but our understanding of iron sensors and signals remains limited. Iron Deficiency-responsive Element-binding Factor 1 (IDEF1) and Hemerythrin motif-containing Really Interesting New Gene- and Zinc-finger proteins (HRZs)/BRUTUS (BTS) have recently emerged as candidate iron sensors because of their functions as potent regulators of iron deficiency responses and their iron-binding properties. IDEF1 is a central transcriptional regulator of graminaceous genes involved in iron uptake and utilization, predominantly during the early stages of iron deficiency. HRZs/BTS are E3 ubiquitin ligases and negative regulators of iron deficiency responses in both graminaceous and non-graminaceous plants. Rice OsHRZ1 and OsHRZ2 are also potent regulators of iron accumulation. Characterizing these putative iron sensors also provides clues to understanding the nature of iron signals, which may involve ionized iron itself, other metals, oxygen, redox status, heme and iron-sulfur clusters, in addition to metabolites affected by iron deficiency. Systemic iron responses may also be regulated by phloem-mobile iron and its chelators such as nicotianamine. Iron sensors and signals will be identified by demonstration of signal transmission by IDEF1, HRZs/BTS, or unknown factors. © 2014 The Authors.


Ikemoto H.,University of Tokyo | Yoshino T.,University of Tokyo | Sakata K.,Hoshi University | Sakata K.,Japan Science and Technology Agency | And 3 more authors.
Journal of the American Chemical Society | Year: 2014

A unique synthetic utility of a Cp*CoIII catalyst in comparison with related Cp*RhIII catalysts is described. A C2-selective indole alkenylation/annulation sequence proceeded smoothly with catalytic amount of a [Cp*CoIII(C6H 6)](PF6)2 complex and KOAc. Intramolecular addition of an alkenyl-Cp*Co species to a carbamoyl moiety gave pyrroloindolones in 58-89% yield in one pot. Clear difference was observed between the catalytic activity of the Cp*CoIII complex and those of Cp*RhIII complexes, highlighting the unique nucleophilic activity of the organocobalt species. The Cp*CoIII catalysis was also suitable for simple alkenylation process of N-carbamoyl indoles, and broad range of alkynes, including terminal alkynes, were applicable to give C2-alkenylated indoles in 50-99% yield. Mechanistic studies on C-H activation step under Cp*CoIII catalysis with the aid of an acetate unit as well as evaluation of the difference between organo-Co III species and organo-RhIII species are also described. © 2014 American Chemical Society.


Setaka W.,Tokushima Bunri University | Setaka W.,Japan Science and Technology Agency | Yamaguchi K.,Tokushima Bunri University
Journal of the American Chemical Society | Year: 2012

A macrocage molecule with a bridged phenylene rotor has been reported as a molecular gyrotop, because the rotor can rotate even in a crystalline state. Although the most stable cage structure of the molecular gyrotop in a crystal was folded and shrunken at low temperature, expansion of the cage was observed at high temperature due to rapid rotation of the phenylene in a crystal. This phenomenon is analogous to the deflation and inflation of a balloon. Moreover, the unusually large thermal expansion coefficient of the crystal was estimated in the temperature range in which the expansion of the cage was observed, indicating a new function of dynamic states of the molecules. © 2012 American Chemical Society.


Shigenobu S.,Japan National Institute for Basic Biology | Shigenobu S.,Japan Science and Technology Agency | Wilson A.C.C.,University of Miami
Cellular and Molecular Life Sciences | Year: 2011

The symbiosis of the pea aphid Acyrthosphion pisum with the bacterium Buchnera aphidicola APS represents the best-studied insect obligate symbiosis. Here we present a refined picture of this symbiosis by linking pre-genomic observations to new genomic data that includes the complete genomes of the eukaryotic and prokaryotic symbiotic partners. In doing so, we address four issues central to understanding the patterns and processes operating at the A. pisum/Buchnera APS interface. These four issues include: (1) lateral gene transfer, (2) host immunity, (3) symbiotic metabolism, and (4) regulation. © 2011 The Author(s).


Inokuma Y.,University of Tokyo | Kawano M.,Pohang University of Science and Technology | Fujita M.,University of Tokyo | Fujita M.,Japan Science and Technology Agency
Nature Chemistry | Year: 2011

A variety of host compounds have been used as molecular-scale reaction vessels, protecting guests from their environment or restricting the space available around them, thus favouring particular reactions. Such molecular 'flasks' can endow guest molecules with reactivities that differ from those in bulk solvents. Here, we extend this concept to crystalline molecular flasks, solid-state crystalline networks with pores within which pseudo-solution-state reactions can take place. As the guest molecules can spontaneously align along the walls and channels of the hosts, structural changes in the substrates can be directly observed by in situ X-ray crystallography during reaction. Recently, this has enabled observation of the molecular structures of transient intermediates and other labile species, in the form of sequential structural snapshots of the chemical transformation. Here, we describe the principles, development and applications of crystalline molecular flasks. © 2011 Macmillan Publishers Limited. All rights reserved.


Hasobe T.,Japan Advanced Institute of Science and Technology | Hasobe T.,Japan Science and Technology Agency
Physical Chemistry Chemical Physics | Year: 2010

Recent developments in synthetic and supramolecular techniques have made it possible to control precisely, organize and arrange molecules at the nanometre level. Such synthetic and supramolecular strategies enable us to construct photofunctional molecular architectures for light energy conversion, such as photovoltaics. In photovoltaic cells, processes such as light-harvesting, charge separation for carrier generation, and carrier transport are generally required. Therefore, the construction of supramolecular assemblies based on these three processes is interesting and promising for the future development of photovoltaics. In this perspective, the focus is on the recent developments of supramolecular systems for light energy conversion, which are mainly composed of porphyrin dyes and nanocarbon materials, such as fullerenes and carbon nanotubes. The specific topics are as follows: (i) preparation, photodynamics, and photoelectrochemistry of self-assembled porphyrin nanoparticles prepared by simple blend, (ii) highly organized supramolecular nanoassemblies of porphyrins and fullerenes using gold nanoparticles, dendritic and polypeptide structures, (iii) the supramolecular formation and photoelectrochemical property of carbon nanotubes, and (iv) supramolecular photofunctional nanorods of porphyrins.


Weng H.,Japan Advanced Institute of Science and Technology | Terakura K.,Japan Science and Technology Agency
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

Various exotic phenomena have been observed in epitaxially grown films and superlattices of transition-metal oxides. In these systems, not only the interface properties but also the strain-induced modification in the bulk properties play important roles. With the recent experimental activities in mind, we have studied the epitaxial strain effects on the electronic structure of Mott insulator LaVO3. The present work is based on the calculations using density-functional theory supplemented by adding local Coulomb repulsion U for Vd orbitals. The range of strain studied here extends from c/a=0.98 (bulk LaVO3 case) to c/a=1.107 (LaAlO3 substrate case). In this range of the strain, we have found the following three different antiferromagnetic spin-ordering (SO) phases. For 0.981.095, G -type SO with ferromagnetic OO becomes the ground state. This range includes the case of LaAlO3 substrate. The implications of these results with regard to the experimental data for thin films of LaVO 3 on SrTiO3 and LaAlO3 substrates will be described. Detailed discussion is given on the mechanisms of stabilizing particular combination of SO and OO in each of three phases. © 2010 The American Physical Society.


Baconguis I.,Oregon Health And Science University | Hattori M.,University of Tokyo | Hattori M.,Japan Science and Technology Agency | Gouaux E.,Oregon Health And Science University | Gouaux E.,Howard Hughes Medical Institute
Current Opinion in Structural Biology | Year: 2013

ATP-gated P2X receptors and acid-sensing ion channels are cation-selective, trimeric ligand-gated ion channels unrelated in amino acid sequence. Nevertheless, initial crystal structures of the P2X4 receptor and acid-sensing ion channel 1a in resting/closed and in non conductive/desensitized conformations, respectively, revealed common elements of architecture. Recent structures of both channels have revealed the ion channels in open conformations. Here we focus on common elements of architecture, conformational change and ion permeation, emphasizing general principles of structure and mechanism in P2X receptors and in acid-sensing ion channels and showing how these two sequence-disparate families of ligand-gated ion channel harbor unexpected similarities when viewed through a structural lens. © 2013 Elsevier Ltd.


Patent
Japan Science, Technology Agency, Kyoto University and Nippoh Chemicals Co. | Date: 2011-05-11

A method of the present invention, for producing an aromatic iodine compound, includes the step of causing an iodizing agent, and an aromatic compound whose nucleus has one or more substituent groups and two or more hydrogen atoms, to react with each other under the presence of a certain ether compound. This realizes such a method of producing an aromatic iodine compound that position selectivity in iodizing reaction of an aromatic compound is improved.


A thin film of amorphous metal oxide includes zinc (Zn), silicon (Si) and oxygen (O), the atomic ratio of Zn/(Zn+Si) being 0.30 to 0.95.


Patent
Japan Science, Technology Agency, Miyake and Ebe | Date: 2010-12-08

The present invention aims to provide a plasma generator capable of creating a spatially uniform distribution of high-density plasma. This object is achieved by the following construction. Multiple antennas 16 are located on the sidewall of a vacuum chamber 11, and a RF power source is connected to three or four antennas 16 in parallel via a plate-shaped conductor 19. The length of the conductor of each antenna 16 is shorter than the quarter wavelength of the induction electromagnetic wave generated within the vacuum chamber. Setting the length of the conductor of the antenna in such a manner prevents the occurrence of a standing wave and thereby maintains the uniformity of the plasma within the vacuum chamber. In addition, the plate-shaped conductor 19 improves the heat-releasing efficiency, which also contributes to the suppression of the impedance.


Patent
Tokyo Institute of Technology, Asahi Glass Co., Japan Science and Technology Agency | Date: 2016-11-02

A thin film of amorphous metal oxide includes zinc (Zn), silicon (Si) and oxygen (O), the atomic ratio of Zn / (Zn + Si) being 0.30 to 0.95.


Patent
Japan Science, Technology Agency and Hyogo Prefecture | Date: 2013-05-01

Disclosed are: a physical quantity sensor which can detect multiple physical quantities simultaneously; and a process for producing the physical quantity sensor. Specifically disclosed is a physical quantity sensor (100), which has flexibility or bendability over the entire body thereof, and which comprises a substrate (1), an electrode layer (2) formed on the substrate (1), a piezoelectric element (3a) and a piezoelectric element (3b) both arranged in parallel to each other on the electrode layer (2), electrode layers (4a, 4b) respectively formed on the piezoelectric elements (3a, 3b), and protective layers (5a, 5b, 5c, 5d, 5e) respectively protecting the electrode layer (2), the piezoelectric elements (3a, 3b) and the electrode layers (4a, 4b). The substrate (1), the electrode layer (2), the piezoelectric element (3a) (a first piezoelectric element), the electrode layer (4a) (a third electrode layer) and the protective layers (5a, 5b, 5c, 5d, 5e) constitute a first physical quantity detection unit (6), and the substrate (1), the electrode layer (2), the piezoelectric element (3b) (a second piezoelectric element) and the electrode layer (4b) (a fourth electrode layer) constitute a second physical quantity detection unit (7).


Patent
Japan Advanced Institute of Science, Technology, Japan Science and Technology Agency | Date: 2010-12-22

The present invention provides a method for detecting methylcytosine in DNA rapidly, conveniently, and with high sensitivity. The present invention relates to a method for detecting methylcytosine by using a methylcytosine photocoupling agent (a photoresponsive probe) consisting of nucleic acids having a group represented by the Formula (I), (II), (III) or (IV) as a base moiety.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: INCO.2010-3.2 | Award Amount: 2.58M | Year: 2011

The EU and Japan has recently signed an agreement on cooperation in science and technology. The EU Commissioner for Science and Research, Janez Potonik has stated that This agreement between the EC and Japan opens a new chapter in the history of science and research cooperation between two of the main knowledge providers in the world in a new era of international global cooperation in research. We face common challenges and we should address them together for our planet, for our people and for our future. It also represents one step further in the opening of the European research area to the world. Based on this rationale, CONCERT-Japan is bringing together the European countries to consolidate and structure their S&T cooperation with Japan. One of the main principles of EU FP7 is opening of the European Research Area (ERA) to the world. However, in the case of Japan, this objective still remains to be achieved. In this framework, CONCERT-Japan is an ERA-NET initiative to coordinate, network and enhance S&T cooperation of the European countries with Japan through developing a concerted cooperation approach. To that end, specific features of this ERA-NET action include the definition of common elements in present cooperation, identification of priorities and models for future cooperation, implementation of a pilot joint funding activity and development of a durable programmatic approach for the future. Enabling European countries to speak with one voice in science and technology cooperation with Japan, this project will unveil the mutual interests of Europe and Japan, bolster their position in the global competition for knowledge and elevate research excellence. A consortium consisting of 10 partners from European countries and 3 partners from Japan will realize this ambitious target. When doing this, the consortium will devote utmost care to principles such as inclusiveness, equitable representation, gender equality, environmental responsibility and efficiency.


Patent
Nippoh Chemicals Co., Japan Science and Technology Agency | Date: 2013-01-30

A method of the present invention, for producing an iodizing agent, includes the step of electrolyzing iodine molecules in a solution by using an acid as a supporting electrolyte. This realizes (i) a method of producing an iodine cation suitable for use as an iodizing agent that does not require a sophisticated separation operation after iodizing reaction is completed, and (ii) an electrolyte used in the method. Further, a method of the present invention, for producing an aromatic iodine compound, includes the step of causing an iodizing agent, and an aromatic compound whose nucleus has one or more substituent groups and two or more hydrogen atoms, to react with each other under the presence of a certain ether compound. This realizes such a method of producing an aromatic iodine compound that position selectivity in iodizing reaction of an aromatic compound is improved.


Patent
Kitakyushu Foundation For The Advancement Of Industry, Japan Science and Technology Agency | Date: 2010-07-15

By storing a liquid to be treated in a treatment tank main body 10 having a bottom portion 10g that narrows downward, with particles of materials to be treated dispersed therein, taking out the liquid to be treated from a position lower than the liquid level of the treatment tank main body 10, and returning the liquid to the bottom portion 10g of the treatment tank main body 10, thereby circulating the liquid to be treated while forming a vortex flow within the treatment tank main body 10, and at the same time supplying air bubbles from the lower part of the treatment main unit 10, a first component contained in froths is separated from a second component, which is less susceptible to floatation, contained in the liquid to be treated.


Patent
Nippoh Chemicals Co., Japan Science and Technology Agency | Date: 2013-01-30

A method of the present invention, for producing an iodizing agent, includes the step of electrolyzing iodine molecules in a solution by using an acid as a supporting electrolyte. This realizes (i) a method of producing an iodine cation suitable for use as an iodizing agent that does not require a sophisticated separation operation after iodizing reaction is completed, and (ii) an electrolyte used in the method. Further, a method of the present invention, for producing an aromatic iodine compound, includes the step of causing an iodizing agent, and an aromatic compound whose nucleus has one or more substituent groups and two or more hydrogen atoms, to react with each other under the presence of a certain ether compound. This realizes such a method of producing an aromatic iodine compound that position selectivity in iodizing reaction of an aromatic compound is improved.


Patent
Japan Advanced Institute of Science, Technology, Japan Science and Technology Agency | Date: 2011-01-12

Disclosed is a method for the purification and collection of a nucleic acid comprising a specific nucleotide sequence, which can be carried out within an extremely short period and can achieve both high sequence-specificity and a high collection rate. Specifically disclosed is a method for the purification of a target nucleic acid comprising a specific nucleotide sequence and contained in a nucleic acid mixture. The method comprises the steps of: hybridizing a photo-ligating nucleic acid having a group represented by formula (I) as a base moiety with the target nucleic acid to form a hybrid; irradiating the hybrid of the photo-ligating nucleic acid and the target nucleic acid with light to cause the photo-ligation of the hybrid; removing any un-photo-ligated nucleic acid by washing; and irradiating the hybrid of the photo-ligating nucleic acid and the target nucleic acid with light to cause the photo-cleavage of the hybrid


News Article | February 15, 2017
Site: astrobiology.com

Photosynthesis, creating oxygen and carbohydrates such as glucose from solar energy, water, and CO2, is indispensable for many species on this planet. However, it is unclear exactly how or when organisms evolved the ability to photosynthesize. These questions have fascinated scientists for a long time. A Japanese research group led by Associate Professor ASHIDA Hiroki (Graduate School of Human Development and Environment, Kobe University), Academic Researcher KONO Takunari (Graduate School of Human Development and Environment, Kobe University), and Professor MATSUMURA Hiroyoshi (Ritsumeikan University) has discovered an evolutionary model for the biological function that creates CO2 from glucose in photosynthesis. They found the mechanism in a primitive, non-photosynthesizing microbe. The research group discovered that Methanospirillum hungatei, a microbe (methanogenic archaeon) which is thought to have existed since before the development of photosynthesis, possess genes similar to those that play a role in photosynthesis. Through analysis of the enzymes synthesized by these genes and by investigating the metabolic substances within the organism, carrying out metabolome analysis to locate the trapped CO2, the team proved that Methanospirillum hungatei uses a primitive pathway that closely resembles the metabolic pathway used in photosynthesis to synthesize carbohydrates such as glucose. By clarifying part of the primitive metabolic pathway for photosynthesis, these findings could help to reveal how the photosynthesis system formed during evolution, a mystery that scientists have so far been unable to solve. If further light can be shed on the evolution of photosynthesis, scientists could potentially utilize this information to use and improve upon photosynthetic functions in order to increase production of crops and biofuel. This research was carried out as part of the Japan Science and Technology Agency (JST) Strategic Basic Research Programs. It was a joint project by Kobe University, Ritsumeikan University, the Nara Institute of Science and Technology, Birla Institute of Technology and Science (India), Osaka University and Shizuoka University. The findings were published on January 13 in the online journal Nature Communications. Please click here for further details: http://www.kobe-u.ac.jp/documents/en/NEWS/research/2017_01_31_01-01.pdf


News Article | January 26, 2016
Site: www.nanotech-now.com

Abstract: Healthcare practitioners may one day be able to physically screen for breast cancer using pressure-sensitive rubber gloves to detect tumors, owing to a transparent, bendable and sensitive pressure sensor newly developed by Japanese and American teams. Conventional pressure sensors are flexible enough to fit to soft surfaces such as human skin, but they cannot measure pressure changes accurately once they are twisted or wrinkled, making them unsuitable for use on complex and moving surfaces. Additionally, it is difficult to reduce them below 100 micrometers thickness because of limitations in current production methods. To address these issues, an international team of researchers led by Dr. Sungwon Lee and Professor Takao Someya of the University of Tokyo's Graduate School of Engineering has developed a nanofiber-type pressure sensor that can measure pressure distribution of rounded surfaces such as an inflated balloon and maintain its sensing accuracy even when bent over a radius of 80 micrometers, equivalent to just twice the width of a human hair. The sensor is roughly 8 micrometers thick and can measure the pressure in 144 locations at once. The device demonstrated in this study consists of organic transistors, electronic switches made from carbon and oxygen based organic materials, and a pressure sensitive nanofiber structure. Carbon nanotubes and graphene were added to an elastic polymer to create nanofibers with a diameter of 300 to 700 nanometers, which were then entangled with each other to form a transparent, thin and light porous structure. "We've also tested the performance of our pressure sensor with an artificial blood vessel and found that it could detect small pressure changes and speed of pressure propagation," says Lee. He continues, "Flexible electronics have great potential for implantable and wearable devices. I realized that many groups are developing flexible sensors that can measure pressure but none of them are suitable for measuring real objects since they are sensitive to distortion. That was my main motivation and I think we have proposed an effective solution to this problem." ### This work was conducted in collaboration with the research group of Professor Zhigang Suo at Harvard University, USA. Collaborating institutions Osaka University Harvard University, USA Funding Japan Science and Technology Agency (JST) Exploratory Research for Advanced Technology (ERATO) Someya Bio-Harmonized Electronics Project About University of Tokyo The University of Tokyo is Japan's leading university and one of the world's top research universities. The vast research output of some 6,000 researchers is published in the world's top journals across the arts and sciences. Our vibrant student body of around 15,000 undergraduate and 15,000 graduate students includes over 2,000 international students. Find out more at www.u-tokyo.ac.jp/en/ or follow us on Twitter at @UTokyo_News_en. For more information, please click Contacts: Research contact Professor Takao Someya Department of Electrical Engineering and Information Systems Graduate School of Engineering The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan Tel: +81-3-5841-0411/6756 Fax: +81-3-5841-6709 Press officer contact Graduate School of Engineering Public Relations Office The University of Tokyo The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan Tel: 03-5841-1790 Fax: 03-5841-0529 If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


Hatakeyama H.,Tohoku University | Kanzaki M.,Tohoku University | Kanzaki M.,Japan Science and Technology Agency
Traffic | Year: 2011

Development of a 'static retention' property of GLUT4, the insulin-responsive glucose transporter, has emerged as being essential for achieving its maximal insulin-induced surface exposure. Herein, employing quantum-dot-based nanometrology of intracellular GLUT4 behavior, we reveal the molecular basis of its systematization endowed upon adipogenic differentiation of 3T3L1 cells. Specifically, (i) the endosomes-to-trans-Golgi network (TGN) retrieval system specialized for GLUT4 develops in response to sortilin expression, which requires an intricately balanced interplay among retromers, golgin-97 and syntaxin-6, the housekeeping vesicle trafficking machinery. (ii) The Golgin-97-localizing subdomain of the differentiated TGN apparently serves as an intermediate transit route by which GLUT4 can further proceed to the stationary GLUT4 storage compartment. (iii) AS160/Tbc1d4 then renders the 'static retention' property insulin responsive, i.e. insulin liberates GLUT4 from the static state only in the presence of functional AS160/Tbc1d4. (iv) Moreover, sortilin malfunction and the resulting GLUT4 sorting defects along with retarded TGN function might be etiologically related to insulin resistance. Together, these observations provide a conceptual framework for understanding maturation/retardation of the insulin-responsive GLUT4 trafficking system that relies on the specialized subdomain of differentiated TGN. © 2011 John Wiley & Sons A/S.


Shiogai J.,Tohoku University | Ito Y.,Tohoku University | Mitsuhashi T.,Tohoku University | Nojima T.,Tohoku University | And 2 more authors.
Nature Physics | Year: 2016

Among the recently discovered iron-based superconductors, ultrathin films of FeSe grown on SrTiO3 substrates have uniquely evolved into a high-transition-temperature (T c) superconducting material. The mechanisms for the high-T c superconductivity are under debate, with the superconducting gap mainly characterized with in situ analysis for FeSe films grown by molecular beam epitaxy. Here, we investigate the high-T c superconductivity in ultrathin FeSe using an alternative top-down electrochemical etching technique in a three-terminal transistor configuration. In addition to the high-temperature superconductivity in FeSe on SrTiO3, the electrochemically etched ultrathin FeSe transistor on MgO also exhibits superconductivity around 40 K, implying that the application of an electric field effectively contributes to the high-T c superconductivity in ultrathin FeSe regardless of substrate material. Moreover, the observable critical thickness for the high-T c superconductivity is expanded up to 10 unit cells under an applied electric field and the insulator-superconductor transition is electrostatically controlled. The present demonstration implies that the modification of charge imbalance of holes and electrons by the electric-field effect plays a crucial role in inducing high-T c superconductivity in FeSe-based electric double-layer transistors. © 2016 Macmillan Publishers Limited.


Osaka I.,Hiroshima University | Saito M.,Hiroshima University | Mori H.,Hiroshima University | Koganezawa T.,Japan Synchrotron Radiation Research Institute | And 2 more authors.
Advanced Materials | Year: 2012

A thiazolothiazole-thiophene copolymer is examined as the active material in bulk heterojunction (BHJ) solar cells. By optimizing the molecular weight, the polymer-based cells exhibit power conversion efficiencies as high as 5.7%. The increase in molecular weight improves the orientational order, and blending with phenyl-C61-butyric acid methyl ester (PC 61BM) changes the orientational motif from edge-on to face-on, which accounts for the trend in photovoltaic performances. These results might give new insight into the structure-property relationships in BHJ solar cells. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ando K.,Tohoku University | Ando K.,Keio University | Watanabe S.,University of Cambridge | Mooser S.,University of Cambridge | And 4 more authors.
Nature Materials | Year: 2013

Conjugated polymers and small organic molecules are enabling new, flexible, large-area, low-cost optoelectronic devices, such as organic light-emitting diodes, transistors and solar cells. Owing to their exceptionally long spin lifetimes, these carbon-based materials could also have an important impact on spintronics, where carrier spins play a key role in transmitting, processing and storing information. However, to exploit this potential, a method for direct conversion of spin information into an electric signal is indispensable. Here we show that a pure spin current can be produced in a solution-processed conducting polymer by pumping spins through a ferromagnetic resonance in an adjacent magnetic insulator, and that this generates an electric voltage across the polymer film. We demonstrate that the experimental characteristics of the generated voltage are consistent with it being generated through an inverse spin Hall effect in the conducting polymer. In contrast with inorganic materials, the conducting polymer exhibits coexistence of high spin-current to charge-current conversion efficiency and long spin lifetimes. Our discovery opens a route for a new generation of molecular-structure-engineered spintronic devices, which could lead to important advances in plastic spintronics. © 2013 Macmillan Publishers Limited. All rights reserved.


Osaka I.,Hiroshima University | Osaka I.,Japan Science and Technology Agency | Osaka I.,RIKEN | Saito M.,Hiroshima University | And 3 more authors.
Advanced Materials | Year: 2014

The backbone orientation in the thiophene-thiazolothiazole (TzTz) copolymer system can be altered by tuning of the alky side chain composition. We highlight that the orientation significantly impact their solar cell efficiency in particular when using thicker active layers. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ando K.,Tohoku University | Saitoh E.,Tohoku University | Saitoh E.,Japan Science and Technology Agency | Saitoh E.,Japan Atomic Energy Agency
Physical Review Letters | Year: 2012

Spin pumping driven by bistable exchange spin waves is demonstrated in a Pt/Y 3Fe 5O 12 film under parametric excitation. In the Pt/Y 3Fe 5O 12 film, the spin pumping driven by parametric excitation selectively enhances the relaxation of short-wavelength exchange spin waves, indicating strong coupling between the exchange spin waves and spin currents at the interface through efficient spin transfer. The parametric spin pumping, furthermore, allows direct access to nonlinear spin wave dynamics in combination with the inverse spin Hall effect, revealing unconventional bistability of the exchange spin waves. © 2012 American Physical Society.


Endo Y.,Chiba University | Hirahara K.,Chiba University | Yagi R.,Chiba University | Tumes D.J.,Chiba University | And 2 more authors.
Trends in Immunology | Year: 2014

Immunological memory is a hallmark of adaptive immunity. Memory CD4 T helper (Th) cells are central to acquired immunity, and vaccines for infectious diseases are developed based on this concept. However, memory Th cells also play a critical role in the pathogenesis of various chronic inflammatory diseases, including asthma. We refer to these populations as 'pathogenic memory Th cells.' Here, we review recent developments highlighting the functions and characteristics of several pathogenic memory type Th2 cell subsets in allergic inflammation. Also discussed are the similarities and differences between pathogenic memory Th2 cells and recently identified type 2 innate lymphoid cells (ILC2), focusing on cytokine production and phenotypic profiles. © 2013 Elsevier Ltd.


Sugahara S.,Tokyo Institute of Technology | Sugahara S.,Japan Science and Technology Agency | Nitta J.,Tohoku University
Proceedings of the IEEE | Year: 2010

Spin transistors are a new concept device that unites an ordinary transistor with the useful functions of a spin (magnetoresistive) device. They are expected to be a building block for novel integrated circuits employing spin degrees of freedom. The interesting features of spin transistors are nonvolatile information storage and reconfigurable output characteristics: these are very useful and suitable functionalities for various new integrated circuit architectures that are inaccessible to ordinary transistor circuits. This article reviews the current status and outlook of spin transistors from the viewpoint of integrated circuit applications. The device structure, operating principle, performance, and features of various spin transistors are discussed. The fundamental and key phenomena/technologies for spin injection, transport, and manipulation in semiconductors and the integrated circuit applications of spin transistors to nonvolatile logic and reconfigurable logic are also described. © 2006 IEEE.


Yabu H.,Tohoku University | Yabu H.,Japan Science and Technology Agency
Langmuir | Year: 2013

A bottom-up approach to creating 3D assemblies of Au nanorings by drying aqueous dispersions of PS colloidal particles and Au NPs is shown. The evaporation of water from the dispersion allowed for the formation of hexagonally assembled colloidal crystals and nanorings composed of Au nanoparticles among the PS colloidal particles. The size of the nanorings could be controlled on a scale of tens to hundreds of nanometers. After sintering, the Au NPs formed Au nanorings. This simple approach supplies a potentially useful path to novel plasmonic materials and unique metamaterials for the visible light region. © 2013 American Chemical Society.


Bauer G.E.W.,Tohoku University | Bauer G.E.W.,Technical University of Delft | Saitoh E.,Tohoku University | Saitoh E.,Japan Science and Technology Agency | Van Wees B.J.,Zernike Institute for Advanced Materials
Nature Materials | Year: 2012

Spintronics is about the coupled electron spin and charge transport in condensed-matter structures and devices. The recently invigorated field of spin caloritronics focuses on the interaction of spins with heat currents, motivated by newly discovered physical effects and strategies to improve existing thermoelectric devices. Here we give an overview of our understanding and the experimental state-of-the-art concerning the coupling of spin, charge and heat currents in magnetic thin films and nanostructures. Known phenomena are classified either as independent electron (such as spin-dependent Seebeck) effects in metals that can be understood by a model of two parallel spin-transport channels with different thermoelectric properties, or as collective (such as spin Seebeck) effects, caused by spin waves, that also exist in insulating ferromagnets. The search to find applications-for example heat sensors and waste heat recyclers-is on. © 2012 Macmillan Publishers Limited. All rights reserved.


Toyoda K.,Chiba University | Miyamoto K.,Chiba University | Aoki N.,Chiba University | Morita R.,Hokkaido University | And 2 more authors.
Nano Letters | Year: 2012

We discovered for the first time that light can twist metal to control the chirality of metal nanostructures (hereafter, chiral metal nanoneedles). The helicity of optical vortices is transferred to the constituent elements of the irradiated material (mostly melted material), resulting in the formation of chiral metal nanoneedles. The chirality of these nanoneedles could be controlled by just changing the sign of the helicity of the optical vortex. The tip curvature of these chiral nanoneedles was measured to be <40 nm, which is less than 1/25th of the laser wavelength (1064 nm). Such chiral metal nanoneedles will enable us to selectively distinguish the chirality and optical activity of molecules and chemical composites on a nanoscale and they will provide chiral selectivity for nanoscale imaging systems (e.g., atomic force microscopes), chemical reactions on plasmonic nanostructures, and planar metamaterials. © 2012 American Chemical Society.


D'Souza F.,University of North Texas | Ito O.,Japan Science and Technology Agency
Chemical Society Reviews | Year: 2012

Photosensitized electron-transfer processes of nanocarbon materials hybridized with electron donating or electron accepting molecules have been surveyed in this tutorial review on the basis of the recent results reported mainly from our laboratories. As nano-carbon materials, fullerenes and single wall carbon nanotubes (SWCNTs) have been employed. Fullerenes act as photo-sensitizing electron acceptors with respect to a wide variety of electron donors; in addition, the fullerenes act as good ground state electron acceptors in the presence of light-absorbing electron donors such as porphyrins and phthalocyanines. In the case of SWCNTs, their ground states act as electron acceptor and electron donors, depending on the photosensitizers. For example, with respect to the photoexcited porphyrins and phthalocyanines, SWCNTs usually act as electron acceptors, whereas for the photoexcited fullerenes, SWCNTs act as electron donors. The diameter sorted semi-conductive SWCNTs have been used to verify the size-dependent electron transfer rates. For the confirmation of the electron transfer processes, the transient absorption methods have been widely used, in addition to the time-resolved fluorescence spectral measurements. The kinetic data thus obtained in solution are found to be quite useful to predict the efficiencies of photovoltaic cells constructed on semiconductor nanoparticle modified electrodes and their photocatalytic processes.


Onodera A.,Chiba University | Nakayama T.,Chiba University | Nakayama T.,Japan Science and Technology Agency
Trends in Molecular Medicine | Year: 2015

Epigenetics provides a bridge between genetic and environmental factors, and can change the transcriptional outcome of a gene without changing the genomic sequence. Allergies and autoimmune diseases are caused by both of these factors, and dynamic changes in epigenetic marks have been reported in T cells, which are key players in the pathogenesis of immune-mediated diseases. Advances in technology, including gene knockout systems and high-throughput sequencing, have significantly enhanced the understanding of the lifespan of T cells, including maturation, differentiation and memory formation. In this review, we focus on Polycomb and Trithorax proteins, well-characterized epigenetic modulators, and discuss their role in the epigenetic regulation of T cell differentiation and function. © 2015 Elsevier Ltd.


Iwakura Y.,Tokyo Medical University | Iwakura Y.,Japan Science and Technology Agency | Ishigame H.,Yale University | Saijo S.,Chiba University | Nakae S.,Tokyo Medical University
Immunity | Year: 2011

Interleukin-17A (IL-17A) is the signature cytokine of the recently identified T helper 17 (Th17) cell subset. IL-17 has six family members (IL-17A to IL-17F). Although IL-17A and IL-17F share the highest amino acid sequence homology, they perform distinct functions; IL-17A is involved in the development of autoimmunity, inflammation, and tumors, and also plays important roles in the host defenses against bacterial and fungal infections, whereas IL-17F is mainly involved in mucosal host defense mechanisms. IL-17E (IL-25) is an amplifier of Th2 immune responses. The functions of IL-17B, IL-17C, and IL-17D remain largely elusive. In this review, we describe the identified functions of each IL-17 family member and discuss the potential of these molecules as therapeutic targets. © 2011 Elsevier Inc.


Hamada I.,Tohoku University | Otani M.,Japan National Institute of Advanced Industrial Science and Technology | Otani M.,Japan Science and Technology Agency
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

We present a comparative van der Waals density-functional (vdW-DF) study of graphene adsorbed on (111) surfaces of Ni, Cu, Pd, Ag, Au, and Pt, using the second version of vdW-DF (vdW-DF2) of Lee [Phys. Rev. B 82, 081101(R) (2010)]10.1103/PhysRevB.82.081101 and the exchange functional (C09) developed by Cooper [Phys. Rev. B 81, 161104(R) (2010)]10.1103/PhysRevB.81.161104. We show that the use of the vdW-DF2 correlation together with the C09 exchange yields the most satisfactory results: Adsorption geometries of graphene are in good agreement with available experiment data, and the electronic structure of graphene varies depending on the nature of the substrate. Band-gap opening at the K point observed on the Ni(111) surface is reproduced reasonably well. © 2010 The American Physical Society.


Hikosaka K.,Tohoku University | Hikosaka K.,Japan Science and Technology Agency
Plant, Cell and Environment | Year: 2014

Nitrogen distribution within a leaf canopy is an important determinant of canopy carbon gain. Previous theoretical studies have predicted that canopy photosynthesis is maximized when the amount of photosynthetic nitrogen is proportionally allocated to the absorbed light. However, most of such studies used a simple Beer's law for light extinction to calculate optimal distribution, and it is not known whether this holds true when direct and diffuse light are considered together. Here, using an analytical solution and model simulations, optimal nitrogen distribution is shown to be very different between models using Beer's law and direct-diffuse light. The presented results demonstrate that optimal nitrogen distribution under direct-diffuse light is steeper than that under diffuse light only. The whole-canopy carbon gain is considerably increased by optimizing nitrogen distribution compared with that in actual canopies in which nitrogen distribution is not optimized. This suggests that optimization of nitrogen distribution can be an effective target trait for improving plant productivity. © 2014 John Wiley & Sons Ltd.


Hamada I.,Tohoku University | Tsukada M.,Tohoku University | Tsukada M.,Japan Science and Technology Agency
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

We address the dispersion force in a C 60/Au(111) interface using the van der Waals density functional with improved exchange and nonlocal correlation. We found that the adsorption is solely attributed to the nonlocal correlation, i.e., the van der Waals (vdW) forces, and the correct account of vdW attraction between C 60 molecules is also essential to obtain accurate binding energy. The bonding of C 60 is, however, covalent-like, which is originated from the hybridization of the lowest unoccupied molecular orbital of C 60, in agreement with a previous theoretical study. © 2011 American Physical Society.


Patent
Canon Kabushiki Kaisha, Tokyo Institute of Technology, Japan Science and Technology Agency | Date: 2015-07-22

A novel amorphous oxide applicable, for example, to an active layer of a TFT is provided. The amorphous oxide comprises microcrystals.


Ando K.,Tohoku University | Saitoh E.,Tohoku University | Saitoh E.,Japan Science and Technology Agency | Saitoh E.,Japan Atomic Energy Agency
Nature Communications | Year: 2012

The spin-orbit interaction in a solid couples the spin of an electron to its momentum. This coupling gives rise to mutual conversion between spin and charge currents: the direct and inverse spin Hall effects. The spin Hall effects have been observed in metals and semiconductors. However, the spin/charge conversion has not been realized in one of the most fundamental semiconductors, silicon, where accessing the spin Hall effects has been believed to be difficult because of its very weak spin-orbit interaction. Here we report observation of the inverse spin Hall effect in silicon at room temperature. The spin/charge current conversion efficiency, the spin Hall angle, is obtained as 0.0001 for a p-type silicon film. In spite of the small spin Hall angle, we found a clear electric voltage due to the inverse spin Hall effect in the p-Si film, demonstrating that silicon can be used as a spin-current detector. © 2012 Macmillan Publishers Limited. All rights reserved.


News Article | January 28, 2016
Site: www.cemag.us

University of Tokyo researchers have fabricated a multi-layer microfluidic “organ-on-chip” device that mimics the structure of the human placental barrier that supports blood flow and exchange of material between the mother and fetus. Using this device, the group discovered that shear forces caused by fluid flow in the maternal body induce the formation of microvilli in placental epithelial cells. The cells that make up our bodies are exposed to a variety of stimuli including fluid flow and extension, compression and twisting forces. It is thought that cells maintain cell and tissue function by adapting to their environment in response to such stimuli. The placental barrier, which transports oxygen and nutrients from the maternal blood to fetal blood, is one example of a tissue that has adapted to multiple stimuli. Placental barrier cells are constantly exposed to shear forces from the flow of maternal blood to the placenta. However, little research had been conducted on the effect of this flow on cell morphology and function. The research group of Professor S. Takeuchi and (then) Dr. S. Miura at the University of Tokyo’s Institute of Industrial Science observed that application of fluid flow shear force to placental barrier cells results in the formation of characteristic microvilli on placental epithelial cells and additionally discovered that the glucose transport rate of the protein GLUT1 localized to the microvilli also increased. This has demonstrated that compared to conventional static culture methods in which forces such as that produced by fluid flow are not applied, the application of shear force due to fluid flow induces the formation of microvilli and controls cell function. Further, the group discovered that activation of the calcium ion channel TRPV6 by fluid shear force induces microvilli formation. “The use of microfluidic device technology made possible this discovery that shear force is important for microvilli formation,” says Takeuchi. This discovery of the dynamic response characteristics of epithelial cells will contribute to furthering mechanobiological research. This research was published in the journal Nature Communications. This research is a part of the ERATO “Takeuchi Biohybrid Innovation Project” funded by the Japan Science and Technology Agency.


News Article | April 26, 2016
Site: www.nanotech-now.com

Abstract: A thermoelectric (TE) device*1 using cutting edge thermoelectric conversion technology has been created by a team comprising NEC Corporation, NEC TOKIN Corporation and Tohoku University. The new technology, known as the spin Seebeck effect *2, has conversion efficiency 10 times higher than the conventional method *3. Thermoelectric conversion technology that converts energy abandoned as waste heat back to electric power could potentially save energy and reduce greenhouse gas emissions. Although conventional spin Seebeck thermoelectric devices have the advantage of low manufacturing costs and high versatility and durability, their energy conversion efficiency is inferior. "We have improved the conversion efficiency of this spin Seebeck thermoelectric device by more than 10 times because of its newly developed material and device structure," says Soichi Tsumura, General Manager, IoT Device Research Laboratories, NEC Corporation. "Furthermore, devices made of flexible material, such as resin, have been achieved using a manufacturing process that does not require high-temperature heat treatment." "The conversion efficiency of this new spin thermoelectric device has been improved by almost one million times when compared to the earliest device, and has taken an important step towards practical use as a generator element. The achievement of practical use as a heat flux sensor is also in sight," says Tsumura. The three parties aim to further the research and development of technologies to generate electricity from the large amount of waste heat emitted by things such as plants, data centers and vehicles. These results were achieved as part of the "Saitoh Spin Quantum Rectification Project" led by Tohoku University Professor Eiji Saitoh. It is funded by the Exploratory Research for Advanced Technology (ERATO) program of the Japan Science and Technology Agency (JST). ### Footnotes: *1 The Spin Seebeck effect is a thermoelectric effect discovered in 2008 by Prof. Eiji Saitoh and Associate Prof. Ken-ichi Uchida of Tohoku University (Keio University at that time). This is a phenomenon in which a temperature gradient applied in a magnetic material produces a spin current along the temperature gradient. The spin current is a flow of a magnetic property of an electron, so-called "spin". *2 A thermoelectric device is a device which converts thermal energy directly into electricity and vice versa. *3 Compared with a test module that was produced based on a multi-layered SSE technology published by the Tohoku University group in 2015. *4 The anomalous Nernst effect is a thermoelectric effect discovered about 100 years ago, which relates to the magnetic property of a conductive material. *5 References are as follows, A. Kirihara et. al., Nature Materials 11, (2012) 686. M. Ishida, NEC Technical Journal 66(1), (2013). R. Ramos et. al., Phys. Rev. B 92, (2015) 220407(R) Publication Details: Authors: Title: "Flexible heat-flow sensing sheets based on the longitudinal spin Seebeck effect using one dimensional spin-current conducting films" Journal: Scientific Reports 6, 23114, DOI: 10.1038/srep23114 For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


News Article | August 22, 2016
Site: www.nanotech-now.com

Abstract: Physicists at the University of Basel have succeeded in watching a silver catalyst at work for the first time with the aid of an atomic force microscope. The observations made during an Ullmann reaction have allowed the researchers to calculate the energy turnover and, potentially, to optimize the catalysis. The study, which was performed with experts from Japan and Iran, has been published in the scientific journal Small. The Ullmann reaction examined is a chemical reaction in which silver atoms catalyze the bond between two carbon atoms to which iodine was previously bonded. Although scientists have known about this type of reaction since 1901 and used it for many important chemical conversions, it was not previously possible to observe the intermediate product of the reaction in detail. Using an atomic force microscope, the team of researchers led by Professor Ernst Meyer and Dr. Shigeki Kawai from the Swiss Nanoscience Institute and the Department of Physics at the University of Basel has now succeeded in displaying this reaction at atomic resolution. Surprisingly, it was revealed that the silver atoms react with the molecules at temperatures of around -120°C and seem to curve like a bridge over a river. In the second stage of the reaction, which requires the temperature to be increased to around 105°C and generates the end product, the silver atoms are freed again and two carbon atoms bond together. Calculating energy The Ullmann reaction has been used for chemical syntheses for a long time now. Interest in this linking of carbon atoms has recently increased again because it can be used to bind organic molecules to surfaces and produce solvent-free polymers. Detailed observations of how the catalysts work enable scientists to better understand the reaction process. Previous analyses failed to show the spatial arrangement of the organometallic intermediate product. The detailed images now obtained are the first to allow project partner Professor Stefan Goedecker (Department of Physics, University of Basel) to calculate the energy turnover of the Ullmann reaction examined. This data confirms the unusual spatial arrangement of the intermediate product and indicates how the reaction could be optimized. Relatively low temperatures The observed curving and flexibility of the molecules is probably the reason why the reaction requires relatively low temperatures of 105°C. The molecules are subject to mechanical tension and can therefore react more easily, that is at lower temperatures. If other catalysts could be used to generate intermediate products like these that are subject to tension, then catalytic reactions could also be possible at lower temperatures. This would make ecological and economic sense because traditional catalysts with platinum, rhodium, or palladium often require high operating temperatures of 500°C, which leads to the emission of waste gases in a cold state. ### The research work was the result of a collaboration between the Department of Physics at the University of Basel, the National Institute of Materials Science (Japan), the Japan Science and Technology Agency (Japan), the University of Tokyo (Japan), and Shadid Beheshti University (Iran). For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


« Continental showcases car tires and engine mounts with rubber made from dandelion roots; targeting series production in 5-10 years | Main | Hyundai Motor and Cisco collaborate for global connected car project » NEC Corporation, NEC TOKIN Corporation and TOHOKU UNIVERSITY have jointly created a thermoelectric (TE) device using the spin Seebeck effect (SSE) with conversion efficiency 10 times higher than a test module that was produced based on a multi-layered SSE technology published by the Tohoku University group in 2015. The spin-Seebeck effect is a thermoelectric effect discovered in 2008 by Prof. Eiji Saitoh and Associate Prof. Ken-ichi Uchida of Tohoku University (Keio University at that time). This is a phenomenon in which a temperature gradient applied in a magnetic material produces a spin current along the temperature gradient. The spin current is a flow of a magnetic property of an electron. Thermoelectric conversion technology that converts energy abandoned as waste heat back to electric power is strongly anticipated to be used for saving energy and reducing greenhouse gas emissions. Although conventional spin-Seebeck thermoelectric devices have the advantages of a low manufacturing cost and high versatility and durability, their energy conversion efficiency is inferior. We have improved the conversion efficiency of this spin-Seebeck thermoelectric device by more than 10 times because of its newly developed material and device structure. Furthermore, devices made of flexible material, such as resin, have been achieved using a manufacturing process that does not require high-temperature heat treatment. The conversion efficiency of this new spin thermoelectric device has been improved by almost one million times when compared to the earliest device, and has taken an important step towards practical use as a generator element. The achievement of practical use as a heat flux sensor is also in sight. In the future, the three parties participating in this development aim to further the research and development of technologies to generate electricity from the large amount of waste heat emitted by plants, data centers, vehicles and others. Key features of this new technology are: Development of a low-cost, high-performance ferromagnetic alloy and significant improvement in thermoelectric conversion efficiency. Conventionally, expensive platinum was used as the electrode material to extract electric power in a spin-Seebeck thermoelectric device. This time, new cobalt alloys were developed to replace the platinum. As a result, the cost was significantly reduced. Furthermore, the combination of the thermoelectric effect termed the Anomalous Nernst Effect(ANE), appearing due to the ferromagnetic properties added to the cobalt alloys and the spin Seebeck effect, have improved the thermoelectric conversion efficiency by more than 10 times. The Anomalous Nernst Effect is a thermoelectric effect discovered about 100 years ago, which relates to the magnetic property of a conductive material. Devices with bending resistance and low heat treatment temperature achieved by new deposition technology. New deposition technology fabricates a fine ferrite film for spin-Seebeck thermoelectric devices at 90 ˚C, much lower than the 700 ˚C used with the conventional method. Owing to the decrease in heat treatment temperature, elements can be created on the surface of plastic film, etc., and flexible devices of various shapes are created. This achievement was published in an open access paper in Scientific Reports. These results were achieved as part of the Exploratory Research for Advanced Technology (ERATO) “SAITOH Spin Quantum Rectification Project” (Research Director: Eiji Saitoh, Professor of Tohoku University; Research Period: 2014 - 2020 fiscal year) of the Japan Science and Technology Agency (JST).


Tong H.,Japan International Center for Materials Nanoarchitectonics | Ouyang S.,Japan National Institute of Materials Science | Bi Y.,Japan International Center for Materials Nanoarchitectonics | Umezawa N.,Japan National Institute of Materials Science | And 4 more authors.
Advanced Materials | Year: 2012

Semiconductor photocatalysis has received much attention as a potential solution to the worldwide energy shortage and for counteracting environmental degradation. This article reviews state-of-the-art research activities in the field, focusing on the scientific and technological possibilities offered by photocatalytic materials. We begin with a survey of efforts to explore suitable materials and to optimize their energy band configurations for specific applications. We then examine the design and fabrication of advanced photocatalytic materials in the framework of nanotechnology. Many of the most recent advances in photocatalysis have been realized by selective control of the morphology of nanomaterials or by utilizing the collective properties of nano-assembly systems. Finally, we discuss the current theoretical understanding of key aspects of photocatalytic materials. This review also highlights crucial issues that should be addressed in future research activities. The state-of-the-art research activities in the field of photocatalysis is reviewed to reveal the key issues, challenges, and opportunities facing present and future research on photocatalytic materials. Energy band engineering, nanotechnology, modern materials characterization methods and advanced theoretical studies promise to sustain rapid development of photocatalytic materials to contribute an encouraging prospect in the realization of a sustainable society. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Minari T.,Japan International Center for Materials Nanoarchitectonics | Minari T.,RIKEN | Liu C.,Japan International Center for Materials Nanoarchitectonics | Kano M.,Dai Nippon Printing | And 2 more authors.
Advanced Materials | Year: 2012

The solubility and low processing temperatures of organic semiconductors enable fabrication of electronic devices using relatively simple printing technologies, and hold promise for realizing flexible plastic devices by environment-friendly production methods at low cost. In particular, by effectively using the self-assembling ability of molecules, production methods for organic semiconductor devices are expected to become more efficient in terms of energy and material consumption. We have developed two solution-based methods for self-organized formation of organic semiconductor crystals, including area selective nucleation of crystalline semiconductor films and direct formation of organic single crystals. These bottom-up methods of device fabrication, wherein the intrinsic functionalities of molecules are utilized for spontaneous assembly, may become a core technology for future plastic electronics. Bottom-up fabrication methods based on self assembly of molecules are developed for solution-processed production of organic semiconductor devices. Our methods enable area selective crystallization of molecules and direct formation of organic single crystals from solution. Since these methods can be processed under ambient condition at room temperature, they are fully compatible with printable electronics technology. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Osada M.,Japan International Center for Materials Nanoarchitectonics | Osada M.,Japan Science and Technology Agency | Sasaki T.,Japan International Center for Materials Nanoarchitectonics | Sasaki T.,Japan Science and Technology Agency
Advanced Materials | Year: 2012

Two-dimensional (2D) nanosheets, which possess atomic or molecular thickness and infinite planar lengths, are regarded as the thinnest functional nanomaterials. The recent development of methods for manipulating graphene (carbon nanosheet) has provided new possibilities and applications for 2D systems; many amazing functionalities such as high electron mobility and quantum Hall effects have been discovered. However, graphene is a conductor, and electronic technology also requires insulators, which are essential for many devices such as memories, capacitors, and gate dielectrics. Along with graphene, inorganic nanosheets have thus increasingly attracted fundamental research interest because they have the potential to be used as dielectric alternatives in next-generation nanoelectronics. Here, we review the progress made in the properties of dielectric nanosheets, highlighting emerging functionalities in electronic applications. We also present a perspective on the advantages offered by this class of materials for future nanoelectronics. 2D inorganic nanosheets are interesting dielectric building blocks that can be used as a dielectric analogue of graphene. Layer-by-layer engineering approach of these nanosheets promises unique possibilities to design thin-film device architectures such as capacitors, gate dielectrics, transistors, and artificial ferroelectrics. Trends and recent progress in this class of materials are highlighted and provide a perspective for future nanoelectronics. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wakano J.Y.,Meiji University | Wakano J.Y.,Japan Science and Technology Agency | Iwasa Y.,Kyushu University
Genetics | Year: 2013

Adaptive dynamics formalism demonstrates that, in a constant environment, a continuous trait may first converge to a singular point followed by spontaneous transition from a unimodal trait distribution into a bimodal one, which is called "evolutionary branching." Most previous analyses of evolutionary branching have been conducted in an infinitely large population. Here, we study the effect of stochasticity caused by the finiteness of the population size on evolutionary branching. By analyzing the dynamics of trait variance, we obtain the condition for evolutionary branching as the one under which trait variance explodes. Genetic drift reduces the trait variance and causes stochastic fluctuation. In a very small population, evolutionary branching does not occur. In larger populations, evolutionary branching may occur, but it occurs in two different manners: in deterministic branching, branching occurs quickly when the population reaches the singular point, while in stochastic branching, the population stays at singularity for a period before branching out. The conditions for these cases and the mean branching-out times are calculated in terms of population size, mutational effects, and selection intensity and are confirmed by direct computer simulations of the individual-based model. © 2013 by the Genetics Society of America.


Hashimoto K.,Hiroshima University | Hashimoto K.,Japan Science and Technology Agency | Kano M.,University of Tokyo
Cellular and Molecular Life Sciences | Year: 2013

Neural circuits in neonatal animals contain numerous redundant synapses that are functionally immature. During the postnatal period, unnecessary synapses are eliminated while functionally important synapses become stronger and mature. The climbing fiber (CF) to the Purkinje cell (PC) synapse is a representative model for the analysis of postnatal refinement of neuronal circuits in the central nervous system. PCs are initially innervated by multiple CFs with similar strengths around postnatal day 3 (P3). Only a single CF is selectively strengthened during P3-P7 (functional differentiation), and the strengthened CF undergoes translocation from soma to dendrites of PCs from P9 on (dendritic translocation). Following the functional differentiation, supernumerary CF synapses on the soma are eliminated, which proceeds in two distinct phases: the early phase from P7 to around P11 and the late phase from around P12 to P17. Here, we review our current understanding of cellular and molecular mechanisms of CF synapse elimination in the developing cerebellum. © 2013 The Author(s).


Abe M.,Hiroshima University | Abe M.,Japan Institute for Molecular Science | Abe M.,Japan Science and Technology Agency
Chemical Reviews | Year: 2013

Recent development in diradical chemistry are summarized in detail. Diradicals are long-known chemical species, but they continue to be fascinating molecules because of their inherently high reactivity and their potential molecular functions, which are mainly derived from their small HOMO-LUMO energy gaps. Kinetic stabilization and thermodynamic stabilization have made it possible to isolate diradical species. The terminology of singlet and triplet states in diradicals is derived from the number of energy level in diradicals under an external magnetic field. The triplet state is the ground-state spin multiplicity for diradicals in which a large overlap integral exists between the two energetically degenerate molecular orbitals that are occupied by two electrons. Localized diradicals are key intermediates in processes involving the homolytic bond-cleavage and -formation reactions of cyclic compounds.


Takumi T.,Hiroshima University | Takumi T.,Japan Science and Technology Agency
Journal of Neurodevelopmental Disorders | Year: 2011

Autism is a neurodevelopmental disorder that manifests in childhood as social behavioral abnormalities, such as abnormal social interaction, impaired communication, and restricted interest or behavior. Of the known causes of autism, duplication of human chromosome 15q11-q13 is the most frequently associated cytogenetic abnormality. Chromosome 15q11-q13 is also known to include imprinting genes. In terms of neuroscience, it contains interesting genes such as Necdin, Ube3a, and a cluster of GABAA subunits as well as huge clusters of non-coding RNAs (small nucleolar RNAs, snoRNAs). Phenotypic analyses of mice genetically or chromosomally engineered for each gene or their clusters on a region of mouse chromosome seven syntenic to human 15q11-q13 indicate that this region may be involved in social behavior, serotonin metabolism, and weight control. Further studies using these models will provide important clues to the pathophysiology of autism. This review overviews phenotypes of mouse models of genes in 15q11-q13 and their relationships to autism. © 2011 Springer Science+Business Media, LLC.


Matsunaga S.,University of Tokyo | Matsunaga S.,Japan Science and Technology Agency | Shibasaki M.,Institute of Microbial Chemistry
Chemical Communications | Year: 2014

Cooperative catalysis has proven to be a powerful strategy for realizing high reactivity and selectivity in asymmetric transformations. A variety of cooperative asymmetric catalysts have been developed over the last two decades. In this feature article, recent advances from our research on cooperative asymmetric catalysis, focusing on dinuclear Schiff base catalysis, are described. Design of dinuclear Schiff base catalysts and their applications in several asymmetric C-C and C-N bond-forming reactions under simple proton transfer conditions with perfect atom-economy are discussed in detail. © 2014 The Royal Society of Chemistry.


Yamauchi Y.,Japan International Center for Materials Nanoarchitectonics | Yamauchi Y.,Japan Science and Technology Agency
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan | Year: 2013

Mesoporous materials prepared through the self-assembly of surfactants have attracted wide attention because of their many potential applications. The mesostructural, compositional, and morphological controls of mesoporous materials have been extensively studied thus far. In particular, the macroscopic alignments of one-dimensional (1D) mesochannels and their controls are quite important for the creation of advanced functional materials. In most cases, the direction of mesochannels in mesoporous films lies parallel to the substrate. Vertical orientation of the mesochannels can realize high diffusion and accessibility of guest species from the outside. Here, I review the recent progress on this emerging research field. Various methods have been proposed for the preparation of vertically oriented mesoporous thin films using high magnetic field, shear flow, modification of the substrate, and other methods. I also briefly introduce their applications and a perspective for the future. © 2013 The Ceramic Society of Japan. All rights reserved.


News Article | March 11, 2016
Site: phys.org

In collaboration with Suncall Corporation, and with support provided by the Japan Science and Technology Agency (JST) under the Center of Innovation (COI) Program, Professor Tadao Tsuboyama of the Graduate School of Medicine and his collaborators have recently succeeded in developing an "Attached Robotic Unit Knee-Ankle-Foot Orthothesis", a modular wearable walking assist device designed to aid the rehabilitation of people with walking difficulties.


News Article | March 4, 2016
Site: www.nature.com

Next week will mark five years since 11 March 2011, the day of the devastating Tohoku earthquake and tsunami, and the accident that followed at the Fukushima Daiichi nuclear-power plant of the Tokyo Electric Power Company. The quake and tsunamis killed nearly 16,000 people and injured more than 6,000; 2,600 are still missing. Fukushima prefecture, the location of the crippled nuclear plant, was hit particularly hard1. The Japanese government provisionally rated the severity of the accident on par with the 1986 Chernobyl disaster — a seven on the seven-point International Nuclear and Radiological Event Scale2. Around 110,000 people had to evacuate because of dispersed radionuclides. Despite the large-scale decontamination efforts, about 70,000 former residents are yet to return. Shocked by the fallout, Japan changed its energy policy. The year before the disaster, the 2010 Basic Energy Plan had called for 53% of electricity generation to come from nuclear power by 2030, implying significant new construction. Since the accident, Japan's energy policy has featured an expanded role for renewables and market liberalization — transitioning from a regional-monopoly model to one that is open to competition. (Some policy changes were made after the change in government in December 2012.) In July 2012, reflecting the public's desire for a transition towards renewable energy, Japan introduced a feed-in tariff, which guarantees renewable-energy generators a high price for the electricity that they feed into the grid; it was particularly generous for solar photovoltaics. Installed solar capacity more than quadrupled in the first three years. A whopping 80-gigawatt capacity — 90% greater than Japan's nuclear-power capacity — has been approved. Next month, the retail electricity market will be fully liberalized, attracting a huge number of new entrants to the previously closed market. The government also strengthened nuclear security substantially. A newly created, independent Nuclear Regulation Authority instituted new safety measures in 2013. All of Japan's nuclear-power plants halted operation for inspection after the accident, and the share of nuclear in power generation dropped from about 30% in 2010 to zero in 2014. Only 4 of the 44 reactors have been restarted so far. The public debate on nuclear rumbles on. Still an important resource for this resource-poor nation, it is expected to provide 20–22% of electricity by 2030, under a new long-term energy strategy created in conjunction with Japan's pledge to the United Nations to cut greenhouse-gas emissions. The journey since 2011 has been difficult, with policy controversies on every front. Many of the fraught decisions — on evacuation, clean-up, energy transition and disaster preparedness — were at the science–policy interface3. And scientists, especially those involved in giving policy advice, lost credibility and the trust of the public4. Several initiatives have been launched to rebuild these crucial bridges. One such is an effort by the Japan Science and Technology Agency (JST) on research into scientific advice, and a 'deliberative polling' exercise in August 2012 involving the public that was used to inform the energy policy of the previous government. These efforts are yielding genuine progress, but slowly. We strongly believe that the events and aftermath of 11 March highlighted a fundamental problem with research in Japan: weak connections between disciplines and between Japan's scholars and those working in other countries. In a nation that performs world-class research in conventional disciplines5, interdisciplinary scholarship lags, and Japanese researchers are keenly aware of this. Moreover, the nation's breadth of disciplinary coverage is narrower5 and the rate of international collaboration is lower than in comparable nations (see 'Build bridges'). This has a particularly important implication for energy and environment research, which require the integration of diverse knowledge6, 7 that can come from anywhere in the world. During the Fukushima crisis, researchers who were not used to collaborating with other disciplines (or other nations) struggled to do so8. Two examples illustrate the problem. The first concerns assessing the safety of nuclear-power plants. Probabilistic risk assessment (PRA) is a standard tool to quantitatively evaluate the likelihood of severe accidents and their impacts, using analysis methods such as fault trees and Monte Carlo simulation. Before the earthquake, nuclear experts conducting PRA research in Japan focused on internal events at nuclear plants (mechanical component failures and human errors), dealing mostly with engineering knowledge. What the disaster vividly demonstrated is that nuclear plants are susceptible to external events and that accident impacts are not contained — they may include the release of radionuclides, with dire environmental effects. The PRA has therefore been extended beyond nuclear engineering to cover disciplines ranging from seismology and geology to atmospheric science and ecological modelling. Before 2011, such interdisciplinary PRA research in Japan was limited compared with other developed economies that have significant nuclear presence such as in the United States, the United Kingdom and France (see go.nature.com/sev71o; in Japanese). This was partly because the country did not require PRA for regulatory purposes. Under the new 2013 regulations, Japan mandated the use of PRA for nuclear plants and is now trying to catch up in this area. The second example concerns innovation in renewable energy. Although many citizens would prefer the nation's energy portfolio to have a larger share of renewables, these are more costly in Japan than elsewhere, even for technologies such as solar photovoltaics, in which Japan was a pioneer. Ideally, Japan should explore how each policy alternative might affect future cost trends for solar. Combining energy-systems analysis and policy analysis with technology forecasting methods (based on expert elicitation, bottom-up engineering analysis and learning curves that describe empirical relationships between cumulative production and cost reduction) would yield crucial insights. Such interdisciplinary studies in Japan are hard to come by. Because of the low level of global networking in these areas, international experiences are not widely appreciated in Japan either. This has already affected the solar market in Japan. Under the feed-in tariff, developers rushed to install expensive solar devices, costing consumers trillions of yen that could have been saved by gradual installations made in tandem with cost reductions. In Germany, by contrast, there was a clear incentive for solar developers to reduce cost under its fine-tuned tariff scheme with frequent price adjustments. Our critics will say that these issues are political, not academic. We feel that this attitude is the source of the problem. Engaged scholarship is a prerequisite for informed policymaking. Scientists and social scientists must do their part. Two big changes would go a long way to improving interdisciplinary research in energy and the environment in Japan. Going global is the key, and will pay dividends: Japan would leverage international expertise, and the rest of the world would learn from Japan's experiences. Globalize the review process. Because of the small number of researchers engaged in interdisciplinary research, the pool of reviewers for academic journals and funding proposals is limited. In policy-relevant interdisciplinary research, particularly in energy and environment, publishers and granting programmes, such as the government-backed KAKENHI (Grants-in-Aid for Scientific Research), should make parts or all of their review processes international. The connections made could also boost international collaboration. For strategic research in energy and the environment, funding agencies should require scientists to publish part of their results in international journals even for policy-oriented research, whose target readership obviously prefers Japanese to English. Many papers, although tailored to the policy context of Japan, would appeal to global experts because energy and environmental issues are global. Large-scale programmes of the science-and-technology ministry, and strategic research funds of the environment ministry, should take the lead. Because policymakers need deliverables to be communicated in Japanese as well, this will increase the burden on researchers, which should be reflected in their funds. In April, Japan will start a new round of its Science and Technology Basic Plan, a cabinet-level, five-year policy on research and innovation. It is good to see that building an international researcher network is one of the key agenda items. Japan must make that vision into a reality. Globalize research. Strategic, policy-oriented research programmes in Japan should be designed so that they can benefit from international experience and domestic experience can be shared globally. For example, the Collaborative Laboratories for Advanced Decommissioning Science (CLADS), established as a research base for the decommissioning of the Fukushima plant, should be more outward-facing. Decommissioning involves many disciplines, including nuclear engineering, meteorology and oceanic-risk assessments, ecology and remediation. By soliciting international research proposals, CLADS should involve more researches from elsewhere in Asia, where many countries have nuclear ambitions, including China, South Korea, India and many southeast Asian countries. Working with overseas scientists, CLADS should publish some outcomes in English. Another opportunity is Future Earth, a ten-year global sustainability research initiative that puts interdisciplinarity at the forefront alongside stakeholder engagement9. For its contribution, Japan should elevate energy research to a key component. Japan has several advanced energy technologies, but to move them into the market at scale requires outside input, particularly when it comes to innovation policy. As Asia becomes the centre of the global energy economy, the time is ripe for Japan, as part of the Future Earth platform, to embark on a truly interdisciplinary and international project, and colleagues from neighbouring nations should do the same. Such initiative should receive rigorous academic oversight from an international advisory body. This year is also the 30th anniversary of the Chernobyl nuclear accident. In Europe, and Germany in particular, that disaster spawned fresh thinking on many fronts. The German book Risk Society by Ulrich Beck, published in 1986 soon after the accident, explored how risks from technology and industrialization shape modern society. The disaster catalysed a transition away from nuclear to renewables, which is now gathering renewed momentum, backed up by interdisciplinary studies on energy transformation. As in Germany in the late 1980s, Japan has seen many fresh attempts to carve out new directions for research, but so far such efforts have been fragmented and scattered, many along disciplinary lines. Five years on from March 2011, problems abound. Fukushima and the Tohoku areas are yet to recover, and the transition towards renewables has been rocky. Most, if not all, of these issues are fundamentally political and socio-economic3. But scientists, social scientists and their funders must engage. Without better connections across disciplines and nations, the science–policy interface cannot improve. The people of Japan deserve better.


News Article | March 18, 2016
Site: www.greencarcongress.com

« DOE announces $3M for 2nd round of HPC4Mfg for industry access to high performance computing | Main | IEEE publishes three updated standards to support connected vehicle development » Scientists at Tokyo Institute of Technology, in collaboration with colleagues in Japan, have demonstrated the first electrochemical reaction based on hydride ions in an oxide-based solid-state cell for potential next-generation batteries. A paper on their work is published in the journal Science. Ionic transport has been studied extensively over the years for energy devices such as fuel cells and batteries using Li+, H+, Ag+, Cu+, F–, and O2– as ionic charge carriers. The conduction of hydride ions, H–, is also attractive, the team notes in their paper. In contrast to proton conduction that takes place widely in oxides and other systems, pure H– conduction has been verified only for a few hydrides of alkaline earth metals such as BaH . Unfortunately, utilization of the hydrides is difficult because of their structural inflexibility, which makes control of the lattice structure to create smooth transport pathways and control of the conducting hydride ion content difficult. Using an oxyhydride solid state cell, the researchers have now demonstrated pure H- conduction in an oxide for the first time. Metal hydrides tend to have an inflexible lattice, which makes H– transport difficult, so the researchers turned to oxyhydrides where oxygen and hydrogen share the same lattice sites. Another challenge is the high electron-donating properties of H-, which means that the electrons will dissociate from the H- to produce protons and electrons, giving rise to electron rather than hydride-ion transport. As a result the team sought a system containing cations that were more electron-donating than the H-. Genki Kobayashi and Ryoji Kanno from Tokyo Tech collaborated with colleagues from the Institute for Molecular Science, Japan Science and Technology Agency, Tokyo Institute of Technology, Kyoto University and High Energy Accelerator Research Organization (KEK) in Japan. They examined how the structure of their oxyhydride compounds changed with composition and synthesis conditions. They also studied characteristics of the electronic structure that suggested an ionic Li-H bond in the compound—the existence of H– in the oxides. They then used La LiHO in an orthorhombic structural phase (o-La LiHO ) as an electrolyte in a cell with titanium anode and titanium hydride cathodes. Phase changes at the electrodes by the discharge were consistent with a Ti-H phase diagram suggesting hydride-ion transport. In a Perspective on the work by Kobayashi et al., published in the same issue of Science, Shu Yamaguchi of The University of Tokyo observed that: Kobayashi et al. report a material with pure H− conductivity (and yet an electronic insulator) in an oxyhydride system, which has been a “last frontier” in solid state ionics. … The result … is just the beginning of a new materials science of H− conductivity in oxyhydride systems that will require further elaboration of the underlying mechanisms, as well as potential applications of the extremely reducing H− ion in chemical synthesis. A drawback of the current material is its chemical reactivity in oxidizing atmospheres, but this disadvantage may be overcome by various techniques, like surface protection coatings. These explorations of H− conductors now leave the question of what will be the next last frontier for solid state ionics. This research was supported by Japan Science and Technology Agency (JST), Precursory Research for Embryonic Science and Technology (PRESTO), and Grant-in-Aid for Scientific Research on Innovative Areas from the Japan Society for the Promotion of Science (JSPS).


News Article | November 17, 2015
Site: www.nanotech-now.com

Abstract: University of Tokyo researchers have demonstrated an electrically-controllable valley current device that may pave the way to ultra-low-power "valleytronics" devices. On the atomic scale, matter behaves as both a particle and a wave. Electrons, therefore, have an associated wavelength that usually can have many different values. In crystalline systems however, certain wavelengths may be favored. Graphene, for example, has two favored wavelengths known as K and K' (K prime). This means that two electrons in graphene can have the same energy but different wavelengths - or, to put it another way, different "valley." Electronics use charge to represent information, but when charge flows through a material, some energy is dissipated as heat, a problem for all electronic devices in use today. However, if the same quantity of electrons in a channel flow in opposite directions, no net charge is transferred and no heat is dissipated - but in a normal electronic device this would mean that no information was passed either. A valleytronics device transmitting information using pure valley current, where electrons with the same valley flow in one direction, would not have this limitation, and offers a route to realizing extremely low power devices. Experimental studies on valley current have only recently started. Control of valley current in a graphene monolayer has been demonstrated, but only under very specific conditions and with limited control of conversion from charge current to valley current. In order for valley current to be a viable alternative to charge current-based modern electronics, it is necessary to control the conversion between charge current and valley current over a wide range at high temperatures. Now, Professor Seigo Tarucha's research group at the Department of Applied Physics at the Graduate School of Engineering has created an electrically controllable valley current device that converts conventional electrical current to valley current, passes it through a long (3.5 micron) channel, then converts the valley current back into charge current that can be detected by a measurable voltage. The research group used a graphene bilayer sandwiched between two insulator layers, with the whole device sandwiched between two conducting layers or 'gates', allowing for the control of valley. The group transferred valley current over a distance large enough to exclude other possible competing explanations for their results and were able to control the efficiency of valley current conversion over a wide range. The device also operated at temperatures far higher than expected. "We usually measure our devices at temperatures lower than the liquefaction point of Helium (-268.95 C, just 4.2 K above absolute zero) to detect this type of phenomena," says Dr. Yamamoto, a member of the research group. "We were surprised that the signal could be detected even at -203.15 C (70 K). In the future, it may be possible to develop devices that can operate at room temperature." "Valley current, unlike charge current is non dissipative. This means that no energy is lost during the transfer of information," says Professor Tarucha. He continues, "With power consumption becoming a major issue in modern electronics, valley current based devices open up a new direction for future ultra-low-power consumption computing devices." Collaborating institutions This research was conducted in collaboration with the Center for Emergent Matter Science (CEMS) RIKEN and National Institute for Materials Science. unding The researchers acknowledge support from Japan Society for the Promotion of Science Grant-in-Aid for Scientific Research on Innovative Areas 'Science of Atomic Layers', Canon Foundation, and DFG (Deutsche Forschungsgemeinschaft (German Research Foundation))-JST (Japan Science and Technology Agency) joint research project 'Nano Electronics'. About University of Tokyo The University of Tokyo is Japan's leading university and one of the world's top research universities. The vast research output of some 6,000 researchers is published in the world's top journals across the arts and sciences. Our vibrant student body of around 15,000 undergraduate and 15,000 graduate students includes over 2,000 international students. Find out more at www.u-tokyo.ac.jp/en/ or follow us on Twitter at @UTokyo_News_en. For more information, please click Contacts: Prof. Seigo Tarucha Department of Applied Physics, Graduate School of Engineering, University of Tokyo 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan Tel: +81-3-5841-6835 Fax: +81-3-5841-6835 Dr. Michihisa Yamamoto Department of Applied Physics, Graduate School of Engineering, University of Tokyo 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan Tel: +81-3-5841-6856 Fax: +81-3-5841-6842 If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


Nakao H.,Kyoto University | Nakao H.,Japan Science and Technology Agency | Mikhailov A.S.,Fritz Haber Institute of the Max Planck Society
Nature Physics | Year: 2010

Turing instability in activator-inhibitor systems provides a paradigm of non-equilibrium self-organization; it has been extensively investigated for biological and chemical processes. Turing instability should also be possible in networks, and general mathematical methods for its treatment have been formulated previously. However, only examples of regular lattices and small networks were explicitly considered. Here we study Turing patterns in large random networks, which reveal striking differences from the classical behaviour. The initial linear instability leads to spontaneous differentiation of the network nodes into activator-rich and activator-poor groups. The emerging Turing patterns become furthermore strongly reshaped at the subsequent nonlinear stage. Multiple coexisting stationary states and hysteresis effects are observed. This peculiar behaviour can be understood in the framework of a mean-field theory. Our results offer a new perspective on self-organization phenomena in systems organized as complex networks. Potential applications include ecological metapopulations, synthetic ecosystems, cellular networks of early biological morphogenesis, and networks of coupled chemical nanoreactors. © 2010 Macmillan Publishers Limited. All rights reserved.


Shinoda S.,Osaka City University | Shinoda S.,Japan Science and Technology Agency
Chemical Society Reviews | Year: 2013

Structural dynamism plays important roles in artificial and biological systems, because it controls structures and functions of various molecules and assemblies. In this review, molecular recognition and self-assembling behavior of dynamic armed cyclen-metal complexes are discussed at the molecular and supramolecular levels. These metal complexes provide useful platforms for molecular receptors, supramolecules, and molecular assemblies that can respond rapidly to guest molecules and environments. Since armed cyclens have many structural and geometrical variations, they form a wide variety of metal complexes having specific sensing and signaling functions. The Lewis acidity of the metal cations plays an essential role in anion binding and in hydrolytic catalysis of phosphate esters. Characteristic luminescence and magnetic properties of lanthanides also enable techniques for effective bio-imaging. They also serve as chiral building blocks for self-assembled architectures, which offer chirality integration effective for chirality sensing and signaling at the supramolecular level. © 2013 The Royal Society of Chemistry.


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

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

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