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

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

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

Akaza H.,Tokyo University of Science | Fukuyama T.,Pfizer | Fukuyama T.,Tokyo Medical University
Expert Opinion on Pharmacotherapy | Year: 2014

Introduction: Advanced understanding of the pathogenesis of renal cell carcinoma (RCC) has led to development and approval of several molecularly targeted therapies since 2005. Axitinib is a potent and selective inhibitor of vascular endothelial growth factor receptors 1, 2 and 3. In the randomized Phase III AXIS trial, axitinib significantly prolonged progression-free survival compared with sorafenib, respectively (6.7 vs 4.7 months; p < 0.0001), and improved objective response rate (19 vs 9%; p = 0.0001), resulting in its approval for advanced or metastatic RCC after failure of one systemic therapy. However, overall survival was similar with axitinib and sorafenib. Common adverse events associated with axitinib include diarrhea, hypertension and fatigue. Areas covered: The properties, clinical efficacy, adverse events, pharmacokinetics and pharmacodynamics of axitinib are summarized and its position in the overall therapeutic landscape for metastatic RCC among several targeted therapies is described. Expert opinion: Axitinib is generally well-tolerated and provides definitive clinical benefits in patients with advanced or metastatic RCC as second-line therapy. However, as with other tyrosine kinase inhibitors of the same class, axitinib does not prolong overall survival; therefore, selection of second-line tyrosine kinase inhibitor therapy, including axitinib, must be carefully considered to maximize outcomes for each patient. © Informa UK, Ltd. Source

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

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

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

We systematically examine the fundamental frequencies of shear torsional oscillations in neutron star crusts in a manner that is dependent on the parameter L characterizing the poorly known density dependence of the symmetry energy. The identification of the lowest quasiperiodic oscillation (QPO) among the observedQPOs from giant flares in soft-gamma repeaters as the l = 2 fundamental torsional oscillations enables us to constrain the parameter L as L ≤ 47.4MeV, which is the most conservative restriction on L obtained in the present work that assumes that the mass and radius of the flaring neutron stars range 1.4-1.8M⊙ and 10-14 km. Next, we identify one by one a set of the low-lying frequencies observed in giant flares as the fundamental torsional oscillations. The values of L that can reproduce all the observed frequencies in terms of the torsional oscillations coupled with a part of dripped neutrons via entrainment effects are then constrained as 101.1 ≤ L ≤ 131.0MeV. Alternatively, if only the second lowest frequency observed in SGR 1806-20 has a different origin, one obtains relatively low L values ranging 58.0 ≤ L ≤ 85.3MeV, which seem more consistent with other empirical constraints despite large uncertainties. © 2013 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Source

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

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

Goto Y.,University of Tokyo | Katoh T.,University of Tokyo | Suga H.,University of Tokyo | Suga H.,Tokyo University of Science | Suga H.,Seoul National University of Science and Technology
Nature Protocols | Year: 2011

Genetic code reprogramming is a method for the reassignment of arbitrary codons from proteinogenic amino acids to nonproteinogenic ones; thus, specific sequences of nonstandard peptides can be ribosomally expressed according to their mRNA templates. Here we describe a protocol that facilitates genetic code reprogramming using flexizymes integrated with a custom-made in vitro translation apparatus, referred to as the flexible in vitro translation (FIT) system. Flexizymes are flexible tRNA acylation ribozymes that enable the preparation of a diverse array of nonproteinogenic acyl-tRNAs. These acyl-tRNAs read vacant codons created in the FIT system, yielding the desired nonstandard peptides with diverse exotic structures, such as N-methyl amino acids, D-amino acids and physiologically stable macrocyclic scaffolds. The facility of the protocol allows a wide variety of applications in the synthesis of new classes of nonstandard peptides with biological functions. Preparation of flexizymes and tRNA used for genetic code reprogramming, optimization of flexizyme reaction conditions and expression of nonstandard peptides using the FIT system can be completed by one person in ∼1 week. However, once the flexizymes and tRNAs are in hand and reaction conditions are fixed, synthesis of acyl-tRNAs and peptide expression is generally completed in 1 d, and alteration of a peptide sequence can be achieved by simply changing the corresponding mRNA template. © 2011 Nature America, Inc. All rights reserved. Source

Kanamori H.,Nagoya University | Yasunari T.,Nagoya University | Yasunari T.,Humanity | Kuraji K.,Tokyo University of Science
Journal of Climate | Year: 2013

This study investigates spatiotemporal characteristics of the diurnal cycle (DC) of rainfall over Sarawak in northwest Borneo Island, associated with large-scale intraseasonal disturbances represented by the Madden- Julian oscillation (MJO). This is accomplished using a dense hourly rain gauge network and satellite data. The spatial pattern of theDC is classified into two major groups, coastal and interior regions, based on remarkable differences in rainfall peak times and amplitudes. Amplitudes of the DC and daily rainfall amount increase in active MJO phases at all sites, but the MJO has a stronger effect in the coastal region than the interior region. This modulation of rainfall by the MJO disturbance is largely attributed to rainfall frequency in the interior region, but to both frequency and intensity of rainfall in the coastal region. The low-level westerly wind anomaly enhances convergence, the land-sea breeze, and a midnight rainfall peak in the coastal region during the active MJO phase. Analysis of moisture flux divergence and moist static instability suggests the different dynamics of this modulation of the DC between coastal and interior regions.©2013 American Meteorological Society. Source

Yasumori A.,Tokyo University of Science
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan | Year: 2013

High functionalization of materials by the combination of heterogeneous substances has become an important procedure for the development of high-performance materials. In various procedures for composite processes, the phase separation of glasses has a potential for use with combinations of the varieties of functional materials spontaneously in nanometer and micrometer scale. Moreover, because phase separation is applicable not only to glass-glass combinations but also to glass-crystal combinations which can control both crystalline phase and inside structure of the composite simultaneously, the utilization of phase separation becomes an interesting and effective technique to create novel high-performance composite materials. In this review, the phase separation of inorganic glasses and glass ceramics mainly caused by stable immiscibility phenomena in high-temperature melts and their applications to the preparation of the high-performance composites are summarized. The preparation procedures and the performances of the materials in silicate systems were described specifically, centering on the studies of the author's group such as luminous, magnetic, and photocatalytic materials. © 2013 The Ceramic Society of Japan. All rights reserved. Source

Zhang M.,China Agricultural University | Su Y.-Q.,The Jackson Laboratory | Sugiura K.,Tokyo University of Science | Wigglesworth K.,The Jackson Laboratory | And 2 more authors.
Endocrinology | Year: 2011

Natriuretic peptide type C (NPPC) and its cognate receptor natriuretic peptide receptor 2 (NPR2) are essential for maintaining meiotic arrest in mouse oocytes residing in Graafian follicles. Cumulus cells, which are associated with the oocyte, express the receptor NPR2, a guanylyl cyclase, whereas mural granulosa cells express ligand NPPC. This study determined the temporal expression of Npr2 and the hormonal factors that participate in regulating its expression and, thereby, in oocyte meiotic arrest. Stimulation of follicular development in vivo with equine chorionic gonadotropin (eCG) promoted expression of Npr2 mRNA by cumulus cells and some periantral mural granulosa cells. However, FSH did not elevate the levels of Npr2mRNAin cultured cumulus-oocyte complexes (COCs) isolated from mice not stimulated in vivo with eCG. Nevertheless, estradiol elevated expression of this transcript in vitro to the same steady-state level found in COCs isolated from eCG-stimulated follicles in vivo. Expression of Npr2mRNAwas rapidly reduced in COCs in vitro after isolation from eCG-primed mice unless maintained in culture with estradiol. The ability of NPPC to maintain meiotic arrest in cultured COCs was transient unless culture was in estradiol-containing medium. Ability of cumulus cells to produce cyclic GMP, which is required for the maintenance of meiotic arrest, was also lost in the absence of estradiol, indicating that estradiol is required to maintain functionalNPR2receptorsoncumulus cells in vitro. It is concluded that estradiol promotes and maintains expression of NPR2 in cumulus cells and participates in NPPC-mediated maintenance of oocyte meiotic arrest in vitro. Copyright © 2011 by The Endocrine Society. Source

Watanabe N.,Tokyo University of Science
International Journal of Quantum Information | Year: 2016

We review some notions for quantum dynamical entropies. The dynamical entropy of quantum systems is discussed and a numerical computation of the dynamical entropy is carried for the open system dynamics. © 2016 World Scientific Publishing Company Source

Ohshima H.,Tokyo University of Science
Current Opinion in Colloid and Interface Science | Year: 2013

A review is given on the recent developments of theories of electrokinetics of soft particles (i.e., hard particles covered with an ion-penetrable surface layer of polyelectrolytes) with particular emphasis on the electrophoretic relaxation effects for highly charged soft particles and the effects of inhomogeneous distribution of polymer segments in the surface layer. The electrostatic interaction between soft particles is also discussed. Not only the interaction before contact of the surface layers of the interacting particles but also the interaction after their contact is considered. © 2013 Elsevier Ltd. Source

Yamashita T.,James Franck Institute | Yamashita T.,Tokyo University of Science | Voth G.A.,James Franck Institute
Journal of the American Chemical Society | Year: 2012

Cytochrome c oxidase (CcO), known as complex IV of the electron transport chain, plays several important roles in aerobic cellular respiration. Electrons transferred from cytochrome c to CcO's catalytic site reduce molecular oxygen and produce a water molecule. These electron transfers also drive active proton pumping from the matrix (N-side) to intermembrane region (P-side) in mitochondria; the resultant proton gradient activates ATP synthase to produce ATP from ADP. Although the existence of the coupling between the electron transfer and the proton transport (PT) is established experimentally, its mechanism is not yet fully understood at the molecular level. In this work, it is shown why the reduction of heme a is essential for proton pumping. This is demonstrated via novel reactive molecular dynamics (MD) simulations that can describe the Grotthuss shuttling associated with the PT as well as the dynamic delocalization of the excess proton electronic charge defect. Moreover, the "valve" role of the Glu242 residue (bovine CcO notation) and the gate role of d-propionate of heme a 3 (PRDa3) in the explicit PT are explicitly demonstrated for the first time. These results provide conclusive evidence for the CcO proton transporting mechanism inferred from experiments, while deepening the molecular level understanding of the CcO proton switch. © 2011 American Chemical Society. Source

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

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

Takahashi D.,Tokyo University of Science
Food Policy | Year: 2012

This study aims to evaluate the distributional effect of the governmental rice policy in Japan on producers, consumers, and government expenditures from 1986 to 2010 using a partial equilibrium model. Policy measures include government purchase of rice, output payment, and acreage control. The simulation result shows that acreage control has been the principal policy measure for transferring income to producers, especially since the enforcement of the WTO Agreement on Agriculture. Acreage control is the policy measure with the lowest total efficiency and highest budgetary efficiency. This result implies that the government's goal of transferring income to producers with minimum government cost has been achieved through a combination of policy measures. © 2012 Elsevier Ltd. Source

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

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

Kurisu K.H.,Tokyo University of Science | Bortoleto A.P.,University of Sheffield
Waste Management | Year: 2011

Waste prevention behaviors (WPBs) should be investigated separately from recycling behaviors and analyzed in the context of local policies and measures. Previous studies on WPBs have been mainly conducted in the USA and Europe (mainly in the UK), and studies in Japan have remained very limited to date. Moreover, the effects of socio-demographic factors have been rarely described correctly based on appropriate large sampling. In this study, we conducted an on-line questionnaire survey and obtained 8000 respondents in three megacity regions (Tokyo, Osaka, and Aichi) in Japan. Among these three regions, Osaka respondents showed significantly lower practice rates in nine of 18 WPBs. Particularly in My-bag behavior, the charging of plastic shopping bags strongly affects the practice rate. As shown in the results, local policies and measures affect WPBs. Based on the practice rates, latent four factors were extracted by factor analysis. Multiple regression analysis revealed that gender and age significantly affect WPB factors before local policy effects. © 2011 Elsevier Ltd. Source

Yairi T.,Tokyo University of Science
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

This paper proposes a "co-embedding" method to embed the row and column vectors of an observation matrix data whose large portion is structurally missing into low-dimensional latent spaces simultaneously. A remarkable characteristic of this method is that the co-embedding is efficiently obtained via eigendecomposition of a matrix, unlike the conventional methods which require iterative estimation of missing values and suffer from local optima. Besides, we extend the unsupervised co-embedding method to a semi-supervised version, which is reduced to a system of linear equations.In an experimental study, we apply the proposed method to two kinds of tasks - (1) Structure from Motion (SFM) and (2) Simultaneous Localization and Mapping (SLAM). © 2012 Springer-Verlag. Source

Ohshima H.,Tokyo University of Science
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2014

A three-stage model of the electrostatic interaction between two interpenetrating charged spherical soft particles with no particle core (space-charged porous spheres) in an electrolyte solution is presented. That is, (i) interaction before contact of the two spheres, (ii) partial interpenetration, and (iii) full interpenetration, i.e., engulfing of one sphere by the other. This is an extension of the work of Da¨hnert and Ro¨denbeck (J. Colloid Interface Sci., 163 (1994) 229), who considered the interaction between two interpenetrating vesicle-like surface-charged particles, to the case of the interaction of space-charge porous spheres. Analytic expressions for the interaction energy and force between two interpenetrating weakly charged porous spheres as a function of particle separation are derived for the respective stages on the basis of the linearized Poisson-Boltzmann equations for the electric potential distribution. © 2013 Elsevier B.V. Source

The development of a reaction for the detection of one epigenetic modification in a long DNA strand is a chemically and biologically challenging research subject. Herein, we report and discuss the formation of 5-methylcytosine-osmium complexes that are used as the basis for a bisulfite-free chemical assay for DNA methylation analysis. Osmium in the oxidized state reacts with C5-methylated pyrimidines in the presence of a bipyridine ligand to give a stable ternary complex. On the basis of this reaction, an adenine derivative with a tethered bipyridine moiety has been designed for sequence-specific osmium complex formation. Osmium complexation is then achieved by hybridization of a short DNA molecule containing this functional nucleotide to a target DNA sequence and results in the formation of a cross-linked structure. This novel concept of methylation-specific reaction, based on a straightforward chemical process, expands the range of methods available for the analysis of epigenetic modifications. Advantages of the described method include amplification-insensitive detection, 5-hydroxymethylcytosine complexation, and visualization through methylation-specific in situ hybridization. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Honsho C.,University of Tokyo | Ura T.,Tokyo University of Science | Tamaki K.,University of Tokyo
Journal of Geophysical Research: Solid Earth | Year: 2012

We present a magnetic inversion method in the space domain using Akaike's Bayesian information criterion (ABIC). The horizontal variation of magnetization intensity is represented by a linear combination of bicubic B spline functions, and the problem is set to determine the expansion coefficients. A prior constraint on the roughness of the magnetization variation is incorporated in order to suppress the numerical instability. The ABIC give us the optimal weight of the prior constraint relative to the requirement of fitting the observed data, which is statistically determined from the quality and quantity of the data based on the entropy maximization principle. We applied this method to actual deep-sea magnetic data collected by using an autonomous underwater vehicle and successfully obtained a magnetization distribution that adequately accounts for the observation. The solution does not suffer from the inevitable smoothing due to high-cut filtering or an error caused by reducing the data onto a flat surface as sometimes happens in current inversion methods. Our method is especially useful in handling data collected along a surface of extreme topography over a relatively small area. Copyright 2012 by the American Geophysical Union. Source

De Felice A.,Tokyo University of Science | Suyama T.,University of Tokyo
Progress of Theoretical Physics | Year: 2011

We derive the equation of matter density perturbations on sub-horizon scales around a flat Friedmann-Lemaître-Robertson-Walker background for the general Lagrangian density f(R, G) that is a function of a Ricci scalar R and a Gauss-Bonnet term Q. We find that the effective gravitational constant genetically scales as distance squared at small distances. The effect of this diminishing of the gravitational constant might be important in the gravitational dynamics of cosmic objects such as galaxies, which can be in principle tested by observations. We also provide the general expressions for the effective anisotropic stress, which is useful to constrain modified gravity models from observations of large-scale structure and weak lensing. We also find that there is a special class of theories which evade this unusual behaviour and that the condition to belong to this special class is exactly the same as the one for not having super-luminal modes with propagation speed proportional to their wavenumber. Source

Tani H.,Tokyo University of Science
Journal of Molecular Liquids | Year: 2014

Two-phase Hele-Shaw problem is studied as a model for a two-dimensional radially growing interface. Instead of the Young-Laplace equation, which has been employed in almost all previous studies concerning Hele-Shaw problem, we apply the normal stress balance and derive the new mode coupling equation for perturbation of the interface. In the present research, weakly nonlinear analysis is carried out and time evolution of the interfaces is numerically calculated. These numerical results suggest that our model reflects more exactly the nonlinear features of a radially growing interface, rather than the previous ones based on the Young-Laplace equation. © 2014 Elsevier BV. All rights reserved. Source

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

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

Sumino Y.,Tokyo University of Science | Yoshikawa K.,Doshisha University
European Physical Journal: Special Topics | Year: 2014

In this paper, we demonstrate our recent attempt to construct a chemical model system of amoeboid motion. The system is intended to mimic biological motility based on the generation and collapse of an elastic aggregate; it is composed of oil, water, and surfactants. In this chemical system, the oil-water interface shows extension and retreat of spherical extrusions accompanied by the generation of aggregate on the interface. This instability of the oil-water interface can cause autonomous splitting and motion of a floating oil droplet. The current mathematical model based on the generation of a passive elastic gel is explained, as well as the discrepancy between the model and the experiments. We further describe recently observed microscopic characteristics of the aggregate formation process that might cause the interfacial instability. Finally, we discuss the disadvantage of a chemical model system compared with active colloid and in vitro biological systems, and also mention its potential advantages. © 2014 EDP Sciences and Springer. Source

Ura T.,Tokyo University of Science
Indian Journal of Marine Sciences | Year: 2013

The AUV (Autonomous Underwater Vehicle) is a dynamically stable platform for visual and acoustic observation of the deep sea floor. It can automatically take images of seafloor in high resolution. Two examples of observation carried out by the AUVs r2D4 and Tuna-Sand show significant advantage of the AUV and give us various ideas of AUV application. The first example is the dive to Kuroshima Koll by the hovering type AUV Tuna-Sand in June 2010 following the results of survey by the cruising type AUV r2D4 in January 2010. AUV Tuna-sand brought us photo images of the seafloor where unusual features in the side scanning sonar image captured by the AUV r2D4 were found. Second example is twelve dives over the gas-hydrate field in Toyama bay and took about 7,000 pictures from 2.2 meters above the floor in 1,000 meter depth. One of the mosaic shows that there are 3,500 snow crabs (Chionoecetes japonicas) in a 40 meters by 20 meters area. Source

Hemmer E.,University of Quebec | Vetrone F.,University of Quebec | Soga K.,Tokyo University of Science
MRS Bulletin | Year: 2014

Fast and significant progress has been achieved in the development of new biomarkers in recent years providing promising approaches for the reliable detection of diseases at an early stage. Yet, the disadvantages of commonly used markers, including photobleaching, autofluorescence, phototoxicity, and scattering, when ultraviolet or visible light is used for excitation, need to be overcome. Lanthanide-doped host materials are well known for their excellent optical properties, such as their ability to (up)convert near-infrared excitation to higher energies spanning the ultraviolet, visible, and near-infrared regions or to undergo strong near-infrared luminescence following near-infrared excitation. Their application as biomarkers may overcome the aforementioned drawbacks of conventional dyes. Thus, lanthanide-based nanostructures are highly promising candidates for cellular and small animal imaging, while the assessment of their cytotoxicity remains a crucial issue. Recent developments in the field of upconversion and near-infrared bioimaging focusing on some of the latest results obtained in in vitro and in vivo studies assessing the toxicity of lanthanide-based nanophosphors are highlighted in this review. Copyright © Materials Research Society 2014. Source

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

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

Manzhos S.,Tokyo University of Science | Carrington T.,Queens University | Yamashita K.,University of Tokyo
Journal of Physical Chemistry Letters | Year: 2011

To compute molecular and material properties, one must solve the electronic and/or vibrational Schrödinger equation. This Perspective briefly presents nonspectral (pseudospectral and grid) methods to solve the Schrödinger equation and their recent and promising applications to vibrational and electronic problems. Pseudospectral and grid methods facilitate parallelization, which is of critical importance for modern material modeling applications. By obviating the need to choose basis functions for which exact integrals are possible, they also enable one to use smaller basis sets. For the vibrational problem, pseudospectral and grid methods, in principle, make it possible to compute a vibrational spectrum without a potential surface, simply from values of the potential at points. This is possible if optimized basis functions are used. Iterative eigensolvers are very advantageous when simpler basis functions are used because matrix-vector products can be evaluated efficiently. © 2011 American Chemical Society. Source

Matsusaki M.,Osaka University | Matsusaki M.,Japan Science and Technology Agency | Ajiro H.,Osaka University | Kida T.,Osaka University | And 2 more authors.
Advanced Materials | Year: 2012

The surface design and control of substrates with nanometer- or micrometer-sized polymer films are of considerable interest for both fundamental and applied studies in the biomedical field because of the required surface properties. The layer-by-layer (LbL) technique was discovered in 1991 by Decher and co-workers for the fabrication of polymer multilayers constructed mainly through electrostatic interaction. The scope and applicability of this LbL assembly has been extended by introducing molecularly regular conformations of polymers or proteins by employing, for the first time, weak interactions such as van der Waals interactions and biological recognition. Since these weak interactions are the sum of the attractive or repulsive forces between parts of the same molecule, they allow macromolecules to be easily arranged into the most stable conformation in a LbL film. By applying this characteristic feature, the template polymerization of stereoregular polymers, stereoregular control of surface biological properties, drastic morphological control of biodegradable nano materials, and the development of three-dimensional cellular multilayers as a tissue model were successfully achieved. It is expected that LbL assembly using weak interactions will promote further interest into fundamental and applied studies on the design of surface chemistry in the biomedical field. Layer-by-layer (LbL) assemblies with molecularly regular conformation have been developed by employing weak interactions, van der Waals interactions, and biological recognition. Template polymerization, stereoregular control of biological properties, morphological control of biodegradable nano materials, and three-dimensional cellular multilayers were successfully achieved. It is expected that the LbL assembly with weak interactions promotes further interest for fundamental and applied studies in biomedical field. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Suzuki Y.,Tokyo Institute of Technology | Todoroki A.,Tokyo Institute of Technology | Matsuzaki R.,Tokyo University of Science | Mizutani Y.,Tokyo Institute of Technology
Composites Part A: Applied Science and Manufacturing | Year: 2012

Rapid and automatic inspection of composite aircraft after every flight would reduce the safety factor and allow for more flights. Although, an electrical resistance change method (ERCM) has been proposed, there are many problems with its practical application. In this study, a new diagnostic method, impact-damage visualization, was developed. Indentation damage increases fiber-fiber contact at the interlaminar interface and electrical conductivity. Consequently, electrical current applied to the material will concentrate around the damaged area, and lead to selective and intense resistive heating. This temperature increase can be observed by thermography or detected as a change in electrical resistance caused by the temperature difference. The proposed method had sufficient reliability and sensitivity for practical application as a damage inspection method. © 2011 Elsevier Ltd. All rights reserved. Source

Mori S.,Tokyo University of Science
Environmental Economics and Policy Studies | Year: 2014

This paper evaluates the effects of carbon emission mitigation options from a long-range perspective using an integrated assessment model called MARIA (Multiregional Approach for Resource and Industry Allocation). This model has been developed to assess the potential contribution of fossil, biomass, nuclear, and other energy technologies and land-use changes to future greenhouse gas (GHG) emissions incorporating a simple carbon cycle and climate change model. Two types of policy options play major roles in the GHG mitigation debate; short-term economic instruments and long-term technological options. This paper describes how the model was applied to assess carbon emission stabilization options and strategies based on narrative storylines. The main focus is the long-term assessments of biomass utilization, nuclear power technologies, and carbon sequestration options for stabilizing the atmospheric carbon concentration at 450, 550, and 650ppmv. The results indicate that zero-carbon technologies such as the fast breeder reactor and carbon sequestration technologies can make a significant contribution toward emissions mitigation especially when drastic reductions are envisaged, but the “nuclear phasing out” scenario is still possible. Expansion of biomass appears to be robust. © 2000, Springer Japan. Source

Nagase K.,Tokyo Womens Medical University | Kobayashi J.,Tokyo Womens Medical University | Kikuchi A.,Tokyo University of Science | Akiyama Y.,Tokyo Womens Medical University | And 2 more authors.
Biomaterials | Year: 2011

For the development of temperature-responsive adsorption materials for pharmaceutical protein purification, poly(N-isopropylacrylamide-co-N,N-dimethylaminopropylacrylamide-co-N-tert-butylacrylamide) (P(IPAAm-co-DMAPAAm-co-tBAAm) brush grafted silica beads were prepared through a surface-initiated atom transfer radical polymerization (ATRP). The prepared silica beads as a chromatographic stationary phase were evaluated by observing their thermo-responsive elution profiles of plasma proteins including human serum albumin (HSA) and γ-globulin. Chromatograms of two proteins indicated that negatively-charged HSA was adsorbed on the cationic copolymer brush modified silica beads at higher temperatures with low concentration of phosphate buffer (PB) (pH 7.0) as a mobile phase. The HSA adsorption was attributed to (1) an enhanced electrostatic interaction with the cationic copolymer brush at low concentration of PB and (2) an increased hydrophobic interaction from the dehydrated copolymer at high temperature. Step-temperature gradient enabled HSA and γ-globulin to be separated by the modulation of HSA adsorption/desorption onto the copolymer brush grafted silica beads. These results suggested that the prepared copolymer brush grafted silica beads adsorbed negatively-charged proteins both through electrostatic and hydrophobic interactions by the modulation of column temperature and gave attractive adsorption materials for protein purification process. © 2010 Elsevier Ltd. Source

Ryuman N.,Tokyo University of Science
Oxidative medicine and cellular longevity | Year: 2011

The mechanism of protein S-nitrosation in cells is not fully understood. Using rat 3Y1 cells, we addressed this issue. Among S-nitrosothiols and NO donors tested, only S-nitrosocysteine (CysNO) induced S-nitrosation when exposed in Hanks' balanced salt solution (HBSS) and not in serum-containing general culture medium. In HBSS, NO release from CysNO was almost completely abolished by sequestering metal ions with a metal chelator without affecting cellular S-nitrosation. In contrast, L-leucine, a substrate of L-type amino acid transporters (LATs), significantly inhibited S-nitrosation. The absence of S-nitrosation with CysNO in general culture medium resulted not only from a competition with amino acids in the medium for LATs but also from transnitrosation of cysteine residues in serum albumin. Collectively, these results suggest that in simple buffered saline, CysNO-dependent S-nitrosation occurs through a cellular incorporation-dependent mechanism, but if it occurs in general culture media, it may be through an NO-dependent mechanism. Source

Song C.,Tokyo University of Science | Kitamura Y.,University of Tsukuba | Li S.,University of Tsukuba
Energy | Year: 2014

In the existing coal-fired power plants, the energy penalty associated with CO2 capture process is an important challenge. For this reason, energy analysis has been widely used as a powerful tool to optimize the capture efficiency and reduce energy consumption. In our previous work, a Stirling cooler based cryogenic CO2 capture system was outlined. Process simulation and energy analysis of the system were undertaken in this research. The whole CO2 capture process is composed of three sections: pre-chilling, CO2 anti-sublimation and storage. The energy consumption of each section in the system was investigated in detail. The results show that when the flow rate of flue gas (13vol.% CO2) is set at 5L/min and the temperature of Stirling cooler-1, 2 and 3 is set at -30, -120 and -120°C, respectively, the energy consumption of the pre-chilling, CO2 anti-sublimation and storage sections are 15.58thermalJ/s, 30.48thermalJ/s and 11.40thermalJ/s, respectively. The total energy consumption of the cryogenic CO2 capture system is 57.46thermalJ/s (equal to 689.52J/L flue gas). © 2013 Elsevier Ltd. Source

Hayakawa Y.,Tokyo University of Science | Hayakawa Y.,University of Tokyo
Expert Opinion on Therapeutic Targets | Year: 2012

NKG2D (natural killer group 2, member D) is expressed on the surface of all mouse and human NK cells, and subpopulation of T cells. Stimulation of NK cells through NKG2D triggers cell-mediated cytotoxicity and induces the production of cytokines. NKG2D binds to family of unique ligands with structurally similar to MHC class I, however, NKG2D ligands can be up-regulated in their expression on stressed cells including tumor cells unlike conventional MHC class I molecules. Mounting evidences clearly implicate that NKG2D recognition plays an important role in tumor immune surveillance. Areas covered: While NKG2D detect for potentially dangerous cells, various inhibitory and/or escape mechanisms counteract immune surveillance system and thereby limit effective elimination of transformed tumor cells. In addition, tumors often generate an immunosuppressive microenvironment where inhibitory molecules or cytokines negatively effect the function of anti-tumor immune responses. NKG2D ligand expression can be up-regulated by transcriptional or posttranscriptional mechanisms, therefore, certain therapy targeting those regulatory mechanisms could regain the expression of NKG2D ligands on tumor cells to be detected by the host immune responses. Expert opinion: Our knowledge in the precise mechanism of anti-tumor immunity is rapidly increasing. While NKG2D is known as primary cytotoxicity receptor in NK cell activation by recognizing 'induced-self' ligands on stressed cells including tumor cells, there are increasing evidences that NKG2D recognition can result in both immune activation and immune silencing. Future combined application of conventional cancer therapy and new therapy utilizing such stress-induced recognition systems will provide a novel opportunity to control malignant tumor progression of cancer disease. © 2012 Informa UK, Ltd. Source

Imai T.,Tokyo University of Science
Cold Spring Harbor perspectives in biology | Year: 2010

Sensory systems must map accurate representations of the external world in the brain. Although the physical senses of touch and vision build topographic representations of the spatial coordinates of the body and the field of view, the chemical sense of olfaction maps discontinuous features of chemical space, comprising an extremely large number of possible odor stimuli. In both mammals and insects, olfactory circuits are wired according to the convergence of axons from sensory neurons expressing the same odorant receptor. Synapses are organized into distinctive spherical neuropils--the olfactory glomeruli--that connect sensory input with output neurons and local modulatory interneurons. Although there is a strong conservation of form in the olfactory maps of mammals and insects, they arise using divergent mechanisms. Olfactory glomeruli provide a unique solution to the problem of mapping discontinuous chemical space onto the brain. Source

Li L.J.,Catholic University of Leuven | Nishio T.,Tokyo University of Science | Xu Z.A.,Zhejiang University | Moshchalkov V.V.,Catholic University of Leuven
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

The distribution of vortices at low magnetic fields in single crystals of multiband BaFe2-xNixAs2 (x = 0.1 and x = 0.16) superconductors is studied by Bitter decoration. Highly inhomogeneous vortex patterns, including vortex stripes and vortex clusters, are observed. The origin of these inhomogeneous vortex arrays is likely to be due to strong flux pinning, as suggested by magnetization measurements performed at high fields. Alternative possible scenarios, such as type-1.5 superconductivity due to multiband effect, are also discussed. © 2011 American Physical Society. Source

It has been found that the composition of intestinal microbiota can indicate the risk of disease to each individual. The concepts of biodynamics as used by the Benziger Winery in California, which treats every part of an agricultural environment as a living, breathing entity, can be usefully used in the construction of a system for cancer prevention, which seeks to use the relationship of coexistence (symbiosis) shared between people and intestinal symbiosis, that is, microbiota. Changes in the incidence rate of cancer among Japanese emigrants to Hawaii demonstrate the effect of the changes in the living environment. This leads to the hypothesis that an intake of soy-derived food products and the metabolization of the isoflavones they contain by intestinal microbiota is one of the factors for the significant difference in the incidence rate of prostate cancer among Asian and European/North American populations. It is further hypothesized that isoflavones, particularly equol, are a key factor in the difference in incidence rate between Asia and the West. It is suggested that not having equol converting bacteria in the intestine (non-equol producers) can be a risk factor for prostate cancer and that one direction for future research will be to examine the possibility of improving the intestinal environment to enable equol production. © 2012 Japanese Cancer Association. Source

Koike N.,Tokyo University of Science
Differential Geometry and its Application | Year: 2016

In this paper, we investigate a holonomy invariant elliptic anisotropic surface energy for hypersurfaces in a complete Riemannian manifold, where "holonomy invariant" means that the elliptic parametric Lagrangian (i.e., a Finsler metric) of the Riemannian manifold used to define the anisotropic surface energy is constant along each holonomy subbundle of the tangent bundle of the Riemannian manifold. First we obtain the first variational formula for this anisotropic surface energy. Next we shall introduce the notions of an anisotropic convex hypersurface, an anisotropic equifocal hypersurface and an anisotropic isoparametric hypersurface for this anisotropic surface energy. Also, we shall introduce the notion of an anisotropic tube for this anisotropic surface energy. We prove that anisotropic tubes over a one-point set in a symmetric space are anisotropic convex hypersurfaces and that anisotropic tubes over a certain kind of reflective submanifold in a symmetric space are anisotropic isoparametric and anisotropic equifocal hypersurfaces. © 2015 Elsevier B.V. Source

Uchino K.,Tokyo University of Science
Letters in Mathematical Physics | Year: 2010

We will extend the classical derived bracket construction to any algebra over a binary quadratic operad. We will show that the derived product construction is a functor given by the Manin white product with the operad of permutation algebras. As an application, we will show that the operad of prePoisson algebras is isomorphic to the Manin black product of the Poisson operad with the preLie operad. We will show that differential operators and Rota-Baxter operators are, in a sense, Koszul-dual to each other. © 2010 Springer. Source

Tomo T.,Tokyo University of Science | Allakhverdiev S.I.,RAS Institute of Basic Biological Problems | Mimuro M.,Kyoto University
Journal of Photochemistry and Photobiology B: Biology | Year: 2011

This mini review presents current topics of discussion about photosystem (PS) I and PS II of photosynthesis in the Acaryochloris marina. A. marina is a photosynthetic cyanobacterium in which chlorophyll (Chl) d is the major antenna pigment (>95%). However, Chl a is always present in a few percent. Chl d absorbs light with a wavelength up to 30 nm red-shifted from Chl a. Therefore, the chlorophyll species of the special pair in PS II has been a matter of debate because if Chl d was the special pair component, the overall energetics must be different in A. marina. The history of this field indicates that a purified sample is necessary for the reliable identification and characterization of the special pair. In view of the spectroscopic data and the redox potential of pheophytin, we discuss the nature of special pair constituents and the localization of the enigmatic Chl a. © 2011 Elsevier B.V. All rights reserved. Source

In 1989, the asymmetric Mukaiyama aldol reaction mediated by a Lewis acid consisting of a chiral diamine and Sn(II) triflate was reported. The asymmetric Mukaiyama aldol reaction is now widely used as a versatile tool for the construction of highly advanced, multifunctionalized molecules. In this Personal Account, the history of the development of this powerful methodology and the application of the asymmetric Mukaiyama aldol reaction in the synthesis of natural products are reviewed. Asymmetric total syntheses of various natural products using Sn(II) Lewis acids consisting of chiral diamines derived from l- or d-proline with Sn(OTf)2 were established. In this Personal Account, we demonstrate the wide utility and great versatility of aldol and related addition reactions mediated by the chiral diamine-Sn(OTf)2 complex in the preparation of a number of optically active β-hydroxy carbonyl units (aldols). Copyright © 2014 The Chemical Society of Japan and Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Shiina I.,Tokyo University of Science
Bulletin of the Chemical Society of Japan | Year: 2014

After initially establishing a novel cyclization reaction of ω-hydroxycarboxylic acids (seco-acids) using 4-trifluoromethylbenzoic anhydride (TFBA) and Lewis acid catalysts to form the corresponding lactones, we discovered a more advanced method for this transformation using 2-methyl-6-nitrobenzoic anhydride (MNBA) as a coupling reagent with nucleophilic catalysts. The latter lactonization is promoted by acyl-transfer catalysts, such as 4-(dimethylamino)pyridine (DMAP), 4-pyrrolidinylpyridine (PPY), and 4-(dimethylamino)pyridine N-oxide (DMAPO). (+)-Ricinelaidic acid lactone ((+)-2) was first synthesized by the TFBA-mediated cyclization with Lewis acid catalysts, while the threoaleuritic acid lactone (20) was alternatively synthesized by the MNBA-mediated cyclization with acyl-transfer catalysts. Using this effective lactonization technology to form the ester linkage under mild conditions, we then demonstrated the preparation of various large-, medium-, and small-sized natural and unnatural lactones including (-)-cephalosporolide D ((-)-3), (-)-octalactin A ((-)-4), (-)-octalactin B ((-)-25), 2-epibotcinolide (49), (-)- and (+)-2-hydroxytetracosanolides ((-)-77 and (+)-77), (-)- and (+)-2-hydroxy-24-oxooctacosanolides ((-)-78 and (+)-78), (-)-tetrahydrolipstatin ((-)-THL, (-)-117), and the erythromycin A skeletons 103b, 103c, 104c, and 105b. The transition structures involved in the formation of the β-lactones from the corresponding 3-hydroxycarboxylic acids were then determined using DFT calculations at the B3LYP/6-31G*//B3LYP/6-31G* level, and the reactivity of several seco-acids was successfully predicted on the basis of the calculated thermodynamic properties of the transition structures. © 2013 The Chemical Society of Japan. Source

Fujisawa J.-I.,Tokyo University of Science | Fujisawa J.-I.,Japan Science and Technology Agency
Physical Chemistry Chemical Physics | Year: 2015

Interfacial charge-transfer (ICT) transitions are expected to be a novel charge-separation mechanism for efficient photovoltaic conversion featuring one-step charge separation without energy loss. Photovoltaic conversion due to ICT transitions has been investigated using several TiO2-organic hybrid materials that show organic-to-inorganic ICT transitions in the visible region. In applications of ICT transitions to photovoltaic conversion, there is a significant problem that rapid carrier recombination is caused by organic-inorganic electronic coupling that is necessary for the ICT transitions. In order to solve this problem, in this work, I have theoretically studied light-to-current conversions due to the ICT transitions on the basis of the Marcus theory with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. An apparent correlation between the reported incident photon-to-current conversion efficiencies (IPCE) and calculated reorganization energies was clearly found, in which the IPCE increases with decreasing the reorganization energy consistent with the Marcus theory in the inverted region. This activation-energy dependence was systematically explained by the equation formulated by the Marcus theory based on a simple excited-state kinetic scheme. This result indicates that the reduction of the reorganization energy can suppress the carrier recombination and enhance the IPCE. The reorganization energy is predominantly governed by the structural change in the chemical-adsorption moiety between the ground and ICT excited states. This work provides crucial knowledge for efficient photovoltaic conversion due to ICT transitions. © 2015 the Owner Societies. Source

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

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

Zhong H.,Tokyo University of Science | Fujii K.,University of Tokyo | Nakano Y.,University of Tokyo | Jin F.,Shanghai JiaoTong University
Journal of Physical Chemistry C | Year: 2015

CO2 bubbling into electrolytes is widely used for the electrochemical and photoelectrochemical reduction of CO2 as a carbon source. However, the effects of the CO2 bubbling into the electrolytes have rarely been studied and are not clear. The CO2 bubbling into different electrolytes such as KHCO3, K2CO3, KCl, and KOH was investigated in this research. The concentrations of total dissolved carbon (TC), H2CO3∗ (sum of dissolved CO2 and H2CO3), HCO3 -, and CO3 2- in different solutions before and after bubbling with CO2 until saturation were evaluated. The CO2 bubbling caused the pH of the electrolytes to decrease and affected the existence forms of the dissolved carbonaceous species. After bubbling with CO2, the major form of dissolved CO2 in KHCO3, K2CO3, and KOH was HCO3 -, while H2CO3∗ was the dominant species in KCl, HCl, and H2O. The ratio of H2CO3∗/TC reduces as the concentration of KHCO3 increases, which is possibly the reason for the decrease of CO2 reduction by the solution of high KHCO3 concentration. Furthermore, CO2 partial pressure increasing caused by the CO2 bubbling strongly enhanced the concentration of CO2 in H2O, which is in accordance with Henry's law. © 2014 American Chemical Society. Source

Bauer W.,University of Gottingen | Furutani K.,Tokyo University of Science
Journal of Geometry and Physics | Year: 2010

We analyze the spectral zeta function for sub-Laplace operators on product manifolds M×N. Starting from suitable conditions on the zeta functions on each factor, the existence of a meromorphic extension to the complex plane and real analyticity in a zero neighbourhood is proved. In the special case of N=S1 and using the Poisson summation formula, we obtain expressions for the zeta-regularized determinant. Moreover, we can calculate limit cases of such determinants by inserting a parameter into our formulas. This is a generalization of results in Furutani and de Gosson (2003) [1] and in particular it applies to an intrinsic sub-Laplacian on U(2)≅S3×S1 induced by a sum of squares of canonical vector fields on S3; cf. Bauer and Furutani (2008) [2]. Finally, the spectral zeta function of a sub-Laplace operator on Heisenberg manifolds is calculated by using an explicit expression of the heat kernel for the corresponding sub-Laplace operator on the Heisenberg group; cf. Beals et al. (2000) [18] and Hulanicki (1976) [19]. © 2010 Elsevier B.V. Source

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

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

Xie S.-P.,University of California at San Diego | Kosaka Y.,Tokyo University of Science | Okumura Y.M.,University of Texas at Austin
Nature Geoscience | Year: 2016

The Earth's energy budget for the past four decades can now be closed, and it supports anthropogenic greenhouse forcing as the cause for climate warming. However, closure depends on invoking an unrealistically large increase in aerosol cooling during the so-called global warming hiatus since the late 1990s (refs,) that was due partly to tropical Pacific Ocean cooling. The difficulty with this closure lies in the assumption that the same climate feedback applies to both anthropogenic warming and natural cooling. Here we analyse climate model simulations with and without anthropogenic increases in greenhouse gas concentrations, and show that top-of-the-atmosphere radiation and global mean surface temperature are much less tightly coupled for natural decadal variability than for the greenhouse-gas-induced response, implying distinct climate feedback between anthropogenic warming and natural variability. In addition, we identify a phase difference between top-of-the-atmosphere radiation and global mean surface temperature such that ocean heat uptake tends to slow down during the surface warming hiatus. This result deviates from existing energy theory but we find that it is broadly consistent with observations. Our study highlights the importance of developing metrics that distinguish anthropogenic change from natural variations to attribute climate variability and to estimate climate sensitivity from observations. © 2015 Macmillan Publishers Limited. All rights reserved. Source

Negishi Y.,Tokyo University of Science
Bulletin of the Chemical Society of Japan | Year: 2014

Advances in developments in nanotechnology have encouraged the creation of highly functionalized nanomaterials. Thiolate-protected gold clusters (Aun(SR)m) less than 2 nm in size exhibit size-specific physical and chemical properties not observed in bulk metals. Therefore, they have attracted attention as functional units or building blocks in nanotechnology. The highly stable, magic Aun(SR)m clusters possess great potential as new nanomaterials. We are studying the following subjects related to magic Aun (SR)m clusters: (1) establishing methods to enhance their functionality, (2) developing high-resolution separation methods, and (3) utilizing the clusters as active sites in photocatalytic materials. Through these studies, we aim to create highly functional metal nanoclusters and apply them as highly active photocatalytic materials. The results of our efforts to date are summarized in this paper. © 2013 The Chemical Society of Japan. Source

De Felice A.,Kyoto University | Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

In the approach of the effective field theory of modified gravity, we derive the second-order action and the equation of motion for tensor perturbations on the flat isotropic cosmological background. This analysis accommodates a wide range of gravitational theories including Horndeski theories, its generalization, and the theories with spatial derivatives higher than second order (e.g., Hořava-Lifshitz gravity). We obtain the inflationary power spectrum of tensor modes by taking into account corrections induced by higher-order spatial derivatives and slow-roll corrections to the de Sitter background. We also show that the leading-order spectrum in concrete modified gravitational theories can be mapped on to that in General Relativity under a disformal transformation. Our general formula will be useful to constrain inflationary models from the future precise measurement of the B-mode polarization in the cosmic microwave background. © 2015 American Physical Society. Source

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

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

Hanzawa K.,Tokyo University of Science
Journal of the Physical Society of Japan | Year: 2015

We evaluate the Ruderman-Kittel -Kasuya-Yosida (RKKY) interactions between multipole moments of U4+ ions with 5f2 configuration responsible for the hidden order in URu2Si2. We adopt a generalized periodic Anderson model taking account of all relevant on-site couplings in the 5f2 state and a practical conduction-band structure. A tight-binding model is constructed in terms of maximally localized Wannier functions for conduction bands calculated by a band calculation for ThRu2Si2, and c-f hybridizations are represented by the Slater-Koster integrals. For the Γ1-Γ5 (singlet-doublet) crystalline-electric-field level scheme for 5f2, we obtain the RRKY interactions composed of a predominant antiferro (AF) octupole interaction of Eu (x(y2 - z2); y(z2 - x2)) symmetry, an AF dipole interaction of A2u (z), and a ferro quadrupole interaction of B1g (x2 - y2). Relevance of the present results to the properties of URu2Si2 are discussed. The present formulae can apply to the estimation of c-f exchange and RKKY interactions for rare-earth and actinide heavy-fermion compounds with general fn configurations. © 2015 The Physical Society of Japan. Source

Chen D.H.,Tokyo University of Science | Ushijima K.,Kyushu Sangyo University
Thin-Walled Structures | Year: 2011

This paper discusses the estimation of the initial peak load for circular tubes subjected to axial impact based on a finite element analysis. The peak load depends on the material properties, tube geometries and impact velocity. By changing some parameters systematically, effects of material properties and tube geometries on the peak load are explored. Also, the effect of the impact velocity on the peak load implies both the inertia effect and the material strain rate dependency. By observing the axial stress distribution and deformation behaviour in detail, and by calculating the strain rate near the vertex of a wrinkle when the peak load is observed, both effects on the peak load are clarified. Moreover, an approximate equation to evaluate the peak stress is proposed and in good agreement with the FEM results and other researcher's results under a relatively low impact velocity ( V0<40m/s). © 2011 Elsevier Ltd. Source

Ando S.,Tokyo University of Science
Knowledge and Information Systems | Year: 2016

Class imbalance is a significant issue in practical classification problems. Important countermeasures, such as re-sampling, instance-weighting, and cost-sensitive learning have been developed, but there are limitations as well as advantages to respective approaches. The synthetic re-sampling methods have wide applicability, but require a vector representation to generate additional instances. The instance-based methods can be applied to distance space data, but are not tractable with regard to a global objective. The cost-sensitive learning can minimize the expected cost given the costs of error, but generally does not extend to nonlinear measures, such as F-measure and area under the curve. In order to address the above shortcomings, this paper proposes a nearest neighbor classification model which employs a class-wise weighting scheme to counteract the class imbalance and a convex optimization technique to learn its weight parameters. As a result, the proposed model maintains the simple instance-based rule for prediction, yet retains a mathematical support for learning to maximize a nonlinear performance measure over the training set. An empirical study is conducted to evaluate the performance of the proposed algorithm on the imbalanced distance space data and make comparison with existing methods. © 2015, Springer-Verlag London. Source

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

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

Suzuki M.,Tokyo University of Science
Progress of Theoretical Physics Supplement | Year: 2012

In 1976, the author developed the scaling theory of order formation from unstable states by extending Einstein's linear theory of Brownian motion to nonlinear unstable cases. At the first stage, an exponential growing has been shown to be dominant, namely the initial microscopic fluctuation grows rapidly upto the macroscopic order around the onset time in the scaling regime, where the nonlinearity of the relevant system plays an essential role to stabilize the system. The author found the synergetic effect (or synergism) of the initial fluctuation, random noise and nonlinearity to the formation of macroscopic order. This scaling theory of a single macrovariable or order parameter has been extended to an infinite number of order parameters. The entropy change or entropy production is also discussed from a new point of view, namely from the symmetry of the non-equilibrium density-matrix, using the von Neumann equation. The time derivative of the entropy production for general transport phenomena is also given and consequently this formula yields microscopically the principle of minimum entropy production in the linear response scheme of transport phenomena. Furthermore, we propose here a new principle of minimum dissipation for nonlinear transport phenomena such as nonlinear electric circuits whose resistances depend on currents. Source

Ogata M.,University of Tokyo | Fukuyama H.,Tokyo University of Science
Journal of the Physical Society of Japan | Year: 2015

We derive an exact formula of orbital susceptibility expressed in terms of Bloch wave functions, starting from the exact one-line formula by Fukuyama in terms of Green's functions. The obtained formula contains four contributions: (1) Landau-Peierls susceptibility, (2) interband contribution, (3) Fermi surface contribution, and (4) contribution from occupied states. Except for the Landau-Peierls susceptibility, the other three contributions involve the crystalmomentum derivatives of Bloch wave functions. Physical meaning of each term is clarified. The present formula is simplified compared with those obtained previously by Hebborn et al. Based on the formula, it is seen first of all that diamagnetism from core electrons and Van Vleck susceptibility are the only contributions in the atomic limit. The band effects are then studied in terms of linear combination of atomic orbital treating overlap integrals between atomic orbitals as a perturbation and the itinerant feature of Bloch electrons in solids are clarified systematically for the first time. © 2015 The Physical Society of Japan. Source

Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We study the possibility of realizing a growth rate of matter density perturbations lower than that in general relativity. Using the approach of the effective field theory of modified gravity encompassing theories beyond Horndeski, we derive the effective gravitational coupling Geff and the gravitational slip parameter η for perturbations deep inside the Hubble radius. In Horndeski theories we derive a necessary condition for achieving weak gravity associated with tensor perturbations, but this is not a sufficient condition due to the presence of a scalar-matter interaction that always enhances Geff. Beyond the Horndeski domain it is possible to realize Geff smaller than Newton's gravitational constant G, while the scalar and tensor perturbations satisfy no-ghost and stability conditions. We present a concrete dark energy scenario with varying ct and numerically study the evolution of perturbations to confront the model with the observations of redshift-space distortions and weak lensing. © 2015 American Physical Society. Source

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

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

Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

The disformal transformation of metric gμν→Ω2(φ)gμν+Γ(φ,X)∂μφ∂νφ, where φ is a scalar field with the kinetic energy X=∂μφ∂μφ/2, preserves the Lagrangian structure of Gleyzes-Langlois-Piazza-Vernizzi theories (which is the minimum extension of Horndeski theories). In the presence of matter, this transformation gives rise to a kinetic-type coupling between the scalar field φ and matter. We consider the Einstein frame in which the second-order action of tensor perturbations on the isotropic cosmological background is of the same form as that in General Relativity and study the role of couplings at the levels of both background and linear perturbations. We show that the effective gravitational potential felt by matter perturbations in the Einstein frame can be conveniently expressed in terms of the sum of a General Relativistic contribution and couplings induced by the modification of gravity. For the theories in which the transformed action belongs to a class of Horndeski theories, there is no anisotropic stress between two gravitational potentials in the Einstein frame due to a gravitational demixing. We propose a concrete dark energy model encompassing Brans-Dicke theories as well as theories with the tensor propagation speed ct different from 1. We clarify the correspondence between physical quantities in the Jordan/Einstein frames and study the evolution of gravitational potentials and matter perturbations from the matter-dominated epoch to today in both analytic and numerical approaches. © 2015 American Physical Society. Source

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

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

Yanagi Y.,Tokyo University of Science | Ueda K.,University of Tokyo
Physical Review B - Condensed Matter and Materials Physics | Year: 2016

The magnetic properties of FeGe and FeSi are studied in a unified way on the basis of the realistic model derived from the first principle calculations. We can show that, with decreasing the temperature, the transition from the paramagnetic metallic state to the ferromagnetic metallic state takes place for FeGe, while the transition of FeSi from the paramagnetic metal to the paramagnetic insulator is a continuous crossover, consistent with experiments. It is shown that the distinct magnetic behaviors in FeGe and FeSi are attributed to the difference of the strength of the electron correlation effects, controlled by the effective bandwidth. © 2016 American Physical Society. Source

The phylogenetic position of an anaerobic, non-spore-forming thermophile 'Thermobaculum terrenum' was investigated on the basis of gene order data from completely sequenced bacterial genomes. Gene order data can be an excellent source of phylogenetic information. Shared gene arrangements are unlikely to have arisen by chance convergence. They are likely to reflect common ancestry. 'Thermobaculum terrenum' was found to share three gene arrangements that are present uniquely in genomes of members of the phylum 'Chloroflexi', indicating convincingly that 'Thermobaculum terrenum' is a member of this phylum. Branching orders within the phylum 'Chloroflexi' were inferred by identifying monophyletic groups of species, which were circumscribed by characteristic gene arrangements. The branching orders thus inferred were in good agreement with previously reported phylogenies based on single 16S rRNA gene sequences and on multiple protein sequences. The gene order comparisons revealed a close phylogenetic affinity of 'Thermobaculum terrenum' to Sphaerobacter thermophilus and Thermomicrobium roseum. © 2011 IUMS Printed in Great Britain. Source

Sarkar S.,Indian Institute of Technology Kharagpur | Sinha A.K.,Indian Institute of Technology Kharagpur | Pradhan M.,Indian Institute of Technology Kharagpur | Basu M.,Indian Institute of Technology Kharagpur | And 2 more authors.
Journal of Physical Chemistry C | Year: 2011

A nonpolar surfactant assisted mild wet chemistry approach has been presented for controlled fabrication of ferromagnetic ultralong (several micrometers in length) prickly nickel nanowires in gram scale with the assistance of hydrazine hydrate as the reducing agent and nickel chloride as the metal ion precursor. Nanowire structures analogous to the natural plant Euphorbia milii resulted due to the magnetic dipole driven self-assembly, and their alignment was oriented desirably with an external magnetic field. Systematic microscopic characterizations identified the nanowire to be pure fcc-Ni (i.e., face-centered cubic Ni) without any signature of contamination, though X-ray photoelectron spectroscopy (XPS) and magnetization measurements refer to the existence of an ultrathin nickel oxide (NiO) layer over the nanostructures. The as-synthesized nanowires were used as a single-source precursor for the evolution of nanometric black NiO when calcined. Again, the Ni nanowires act as a sacrificial template that addresses deposition of metallic gold over the nanowire with variable structural hierarchy through their quantitative oxidative dissolution. Then, the composite material serves as a heterogeneous catalyst for reduction of 4-nitrophenol, and a probable reaction mechanism has been suggested. Additionally, the materials were proved to furnish a full-proof enhanced field effect for prolific surface-enhanced Raman scattering (SERS) activity. In a nutshell, the strategy provides a new horizon to design need-based functional material with much practical implication. © 2010 American Chemical Society. Source

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

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

Watanabe N.,Tokyo University of Science
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2016

Quantum entropy and channel are fundamental concepts for quantum information theory progressed recently in various directions. We will review the fundamental aspects of mean entropy and mean mutual entropy and calculate them for open system dynamics. © 2016 The Author(s) Published by the Royal Society. Source

Chen D.-H.,Tokyo University of Science
Acta Mechanica Sinica/Lixue Xuebao | Year: 2011

In this study, the flexural rigidity of a honeycomb consisting of regular hexagonal cells is investigated. It is found that the honeycomb bending can not be evaluated by using the equivalent elastic moduli obtained from the in-plane deformation because the moments acting on the inclined cell wall are different for in-plane deformation and bending deformation. Based on the fact that the inclined wall is twisted under the condition of the rotation angle in both connection edges being zero, a theoretical technique for calculating the flexural rigidity of honeycombs is proposed, and the validity of the present analysis is demonstrated by numerical results obtained by BFM. © 2011 The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg. Source

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

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

Koike N.,Tokyo University of Science
Differential Geometry and its Application | Year: 2014

In this paper, we investigate complete curvature-adapted submanifolds with maximal flat section and trivial normal holonomy group in symmetric spaces of compact type or non-compact type under a certain condition, and derive the constancy of the principal curvatures of such submanifolds. As a result, we derive that such submanifolds are isoparametric. © 2014. Source

Ishii N.,University of Tokyo | Kaneshima K.,University of Tokyo | Kitano K.,University of Tokyo | Kanai T.,University of Tokyo | And 2 more authors.
Optics Letters | Year: 2012

We report on the generation of 9.0 fs, 550 μJ, carrier-envelope phase (CEP)-stabilized optical pulses around 1.6 μmat 1 kHz. Few-cycle IR pulses are obtained from a BiB3O6 optical parametric chirped-pulse amplifier. The amplification of nearly octave-spanning ultrabroad pulses without spectral broadening results in good stability in output energy (0.85% rms) and CEP (160 mrad rms). We observed high harmonics in the water window from a neon cell that corresponds to a laser intensity of 4.1 × 1014 W/cm2. © 2012 Optical Society of America. Source

Sakuma Y.,Tokyo University of Science
Operations Research Letters | Year: 2010

This paper considers a parallel queueing model with heterogeneous servers, where an arriving customer joins the shortest queue and jockeying between queues is permitted. Based on the matrix analytic approach pioneered by Neuts, we obtain the tail decay rate of the stationary distribution for this queueing model. © 2009 Elsevier B.V. All rights reserved. Source

Kojima S.,Tokyo University of Science
Yakugaku Zasshi | Year: 2014

We previously reported that low doses (0.25-0.5 Gy) of γ-rays induce intracellular antioxidant, radioresistant, DNA damage repair, and so on. Meanwhile, we have recently reported that ATP is released from the cells exposed to low-dose γ-rays. Here, it was investigated whether or not g-radiation-induced release of extracellular ATP contributes to various radiation effects, in paricular, focusing on the inductions of intracellular antioxidant and DNA damage repair. Irradiation with γ-rays or exogenously added ATP increased expression of intracellular antioxidants such as thioredoxin and the increases were blocked by pretreatment with an ecto-nucleotidase in both cases. Moreover, release of ATP and autocrine/paracrine positive feedback through P2Y receptors serve to amplify the cellular repair response to radiation-induced DNA damage. To sum up, it would be suggested that ATP signaling is important for the effective induction of radiation stress response, such as protection of the body from the radiation and DNA damage repair. In addition, the possibility that this signaling is involved in the radiation resistance of cancer cells and beneficial effect on the organism of low-dose radiation and radiation adaptive response, would be further suggested. © 2014 The Pharmaceutical Society of Japan. Source

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

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

Goto H.,Nagoya University | Goto H.,Tokyo University of Science | Yokochi Y.,Nagoya University | Yashima E.,Nagoya University
Chemical Communications | Year: 2012

A regioregular achiral polythiophene bearing oxazoline pendant groups formed a unique optically active metal-induced supramolecular aggregate upon complexation with chiral amines or in the presence of a chiral polythiophene in a good solvent for the polymers, thus showing an induced circular dichroism. © The Royal Society of Chemistry 2012. Source

Nagasawa M.,Azabu University | Nagasawa M.,Jichi Medical University | Mitsui S.,Azabu University | En S.,Azabu University | And 6 more authors.
Science | Year: 2014

Human-like modes of communication, including mutual gaze, in dogs may have been acquired during domestication with humans. We show that gazing behavior from dogs, but not wolves, increased urinary oxytocin concentrations in owners, which consequently facilitated owners' affiliation and increased oxytocin concentration in dogs. Further, nasally administered oxytocin increased gazing behavior in dogs, which in turn increased urinary oxytocin concentrations in owners. These findings support the existence of an interspecies oxytocin-mediated positive loop facilitated and modulated by gazing, which may have supported the coevolution of human-dog bonding by engaging common modes of communicating social attachment. © 2014, American Association for the Advancement of Science. All rights reserved. Source

Takemura H.,Tokyo University of Science
Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C | Year: 2012

This paper presents that the novel target person detecting and tracking method for mobile robots based on updating multi color HS-histogram. To detect and track a specific person, the image processing with color camera is common method for vision based navigation system of mobile robot. The image processing for the target person detecting and tracking by robot vision has many problems such as the image from the vision device located on robot is often influenced by the change of target size, target moving direction and lighting condition. Moreover, it is difficult to detect a target person in the crowd. To solve these problems, we propose "GRUMIC-HS-hist method (Gradual Updating Multi Color HS-histogram method)". In the proposed method, the colors of the tracking object are extracted by HSV color space. To decrease the influence of the illumination changes, a HS-histogram is proposed. The extracting colors on HS-histogram are clustered by Nearest Neighbor Method. The colors on HS-histogram are weighted by the anisotropic asymmetric Gaussian distribution to update the HS-histogram without spreading. This proposed "GRUMIC-HS-hist method" achieves the robust target person detecting and tracking by a mobile robot. In addition, the quantitative evaluation method is also proposed to evaluate the proposed target person detecting and tracking method. The quantitative evaluation method is composed with "Extraction Rate", "Object Detecting Rate" and "Tracking Error". The quantitatively experimental results show that the proposed "GRUMIC-HS-hist method " is the robust method for many problems. © 2012 The Japan Society of Mechanical Engineers. Source

Ohbayashi I.,University of Tokyo | Konishi M.,Tokyo University of Science | Ebine K.,University of Tokyo | Sugiyama M.,University of Tokyo
Plant Journal | Year: 2011

A temperature-sensitive mutant of Arabidopsis, root initiation defective 2-1 (rid2-1), is characterized by peculiar defects in callus formation. To gain insights into the requirements for the reactivation of cell division, we analyzed this mutant and isolated the gene responsible, RID2. The phenotypes of rid2-1 in tissue culture and in seedlings indicated that the rid2 mutation has various (acute and non-acute) inhibitory effects on different aspects of cell proliferation. This suggests that the RID2 function is not directly involved in every cycle of cell division, but is related to 'vitality', supporting cell proliferation. The rid2-1 mutation was shown to cause nucleolar vacuolation and excessive accumulation of various intermediates of pre-rRNA processing. Positional cloning of the RID2 gene revealed that it encodes an evolutionarily conserved methyltransferase-like protein, which was found to localize in the nucleus, with accumulation being most evident in the nucleolus. It can be inferred from these findings that RID2 contributes to the nucleolar activity for pre-rRNA processing, probably through some methylation reaction. © 2011 Blackwell Publishing Ltd. Source

Pentraxin 3 (PTX3), a long pentraxin subfamily member in the pentraxin family, plays an important role in innate immunity as a soluble pattern recognition receptor. Plasma PTX3 is elevated in sepsis (~200 ng/ml) and correlates with mortality. The roles of PTX3 in sepsis, however, are not well understood. To investigate the ligands of PTX3 in sepsis, we performed a targeted proteomic study of circulating PTX3 complexes using magnetic bead-based immunopurification and shotgun proteomics for label-free relative quantitation via spectral counting. From septic patient fluids, we successfully identified 104 candidate proteins, including the known PTX3-interacting proteins involved in complement activation, pathogen opsonization, inflammation regulation, and extracellular matrix deposition. Notably, the proteomic profile additionally showed that PTX3 formed a complex with some of the components of neutrophil extracellular traps. Subsequent biochemical analyses revealed a direct interaction of bactericidal proteins azurocidin 1 (AZU1) and myeloperoxidase with PTX3. AZU1 exhibited high affinity binding (K(D) = 22 ± 7.6 nm) to full-length PTX3 in a calcium ion-dependent manner and bound specifically to an oligomer of the PTX3 N-terminal domain. Immunohistochemistry with a specific monoclonal antibody generated against AZU1 revealed a partial co-localization of AZU1 with PTX3 in neutrophil extracellular traps. The association of circulating PTX3 with components of the neutrophil extracellular traps in sepsis suggests a role for PTX3 in host defense and as a potential diagnostic target. Source

Nonomura T.,Tokyo University of Science | Iizuka N.,University of Tokyo | Fujii K.,Japan Aerospace Exploration Agency
Computers and Fluids | Year: 2010

Freestream and vortex preservation properties of a weighted essentially nonoscillatory scheme (WENO) and a weighted compact nonlinear scheme (WCNS) on curvilinear grids are investigated. While the numerical technique used for the compact difference scheme can be applied to WCNS, applying it to WENO is difficult. This difference is caused by difference in the formulation of numerical fluxes. WENO computed in the generalized coordinate system does not work well for either freestream or vortex preservation, whereas WENO computed in the Cartesian coordinate system works well for both freestream and vortex preservation, but its resolution is lower than that of WCNS. In addition, WENO in the Cartesian coordinate system costs three times as much as WENO or WCNS in the generalized coordinate system. Therefore, WENO in the Cartesian coordinate system is not suitable for solving Euler equations on a curvilinear grid. On the other hand, WCNS computed in the generalized coordinate system works well for freestream and vortex preservation when used with the numerical technique proposed for the compact difference scheme. The results show that WCNS with this numerical technique can be used for an arbitrary grid system. In this paper, the excellent freestream and vortex preservation properties of WCNS when used with the numerical technique, compared with those of WENO, are shown for the first time. © 2009 Elsevier Ltd. All rights reserved. Source

Iwata E.,Nagoya University | Ikeda S.,Nagoya University | Matsunaga S.,Tokyo University of Science | Kurata M.,Nagoya University | And 4 more authors.
Plant Cell | Year: 2011

Increased cellular ploidy is widespread during developmental processes of multicellular organisms, especially in plants. Elevated ploidy levels are typically achieved either by endoreplication or endomitosis, which are often regarded as modified cell cycles that lack an M phase either entirely or partially. We identified GIGAS CELL1 (GIG1)/OMISSION OF SECOND DIVISION1 (OSD1) and established that mutation of this gene triggered ectopic endomitosis. On the other hand, it has been reported that a paralog of GIG1/OSD1, UV-INSENSITIVE4 (UVI4), negatively regulates endoreplication onset in Arabidopsis thaliana. We showed that GIG1/OSD1 and UVI4 encode novel plant-specific inhibitors of the anaphase-promoting complex/ cyclosome (APC/C) ubiquitin ligase. These proteins physically interact with APC/C activators, CDC20/FZY and CDH1/FZR, in yeast two-hybrid assays. Overexpression of CDC20.1 and CCS52B/FZR3 differentially promoted ectopic endomitosis in gig1/osd1 and premature occurrence of endoreplication in uvi4. Our data suggest that GIG1/OSD1 and UVI4 may prevent an unscheduled increase in cellular ploidy by preferentially inhibiting APC/C CDC20 and APC/C FZR, respectively. Generation of cells with a mixed identity in gig1/osd1 further suggested that the APC/C may have an unexpected role for cell fate determination in addition to its role for proper mitotic progression. © 2011 American Society of Plant Biologists. Source

Henry M.,University of Tokyo | Kato Y.,Tokyo University of Science
Resources, Conservation and Recycling | Year: 2014

In order to improve the sustainability of the Asian concrete industry, it is important to understand the effect of regional context considering the widely varying socio-economic conditions present in Asia. This research in Mongolia and Singapore was conducted as a continuation of previous studies in Japan, Thailand and South Korea in order to further contribute to understanding regional context, particularly geographic, climate, and economic factors. Geography and climate were found to strongly affect the means by which durability should be assured in each country, as Singapore has a tropical climate whereas Mongolia experiences a large temperature variation with extremely cold winters. The ability to access construction materials and resources was also related to geography, as Singapore, while resource poor, is an international shipping center, whereas Mongolia has abundant resources but few access routes for imports. Quality control issues in Mongolia could be understood in the context of the lower level of economic development, whereas in Singapore the high level of development has lead to an emphasis on green construction, with the government taking the lead in implementing new systems and technologies. © 2013 Elsevier B.V. All rights reserved. Source

Tada K.,Tokyo University of Science
Proceedings of the SICE Annual Conference | Year: 2010

For tracking a non-rigid moving object in a video sequence, it is effective to evaluate the similarity of color histograms. The MeanShift algorithm is one of the popular algorithms. However, MeanShift algorithm may be unable to correspond to extreme changes of the target rotation movement and rapid movement. Recently, Spatiograms which extended the histogram is also studied and the validity is proved. This paper presents a method combined with Spatiograms and MeanShift in order to respond to changes which cannot be tracking by the conventional MeanShift algorithm, and we aimed at robust tracking. © 2010 SICE. Source

Shimotomai M.,Tokyo University of Science
Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science | Year: 2016

Although a coherent-incoherent transition in the ε-carbide precipitated in steels is supposedly linked to hardening and microstructural changes, the existence of this transition has not yet been confirmed. In this paper, we investigate this subject using mechanical spectroscopy. By measuring mechanical loss spectra below room temperature of quench-aged Fe-C alloys, mild steel, and pearlitic steel, we reveal a new broad peak (NBP). This peak is related to thermal activation, and its line shape obeys the equation of the Debye peak with a distribution in relaxation time. The Arrhenius plot yielded a large activation energy and gigantic pre-exponential factor. Its intensity grew by aging at temperatures where precipitation of ε-carbide has been reported. However, it starts to decay at duration far too early for ε-carbide to transform to cementite. For isothermal aging at 393 K (120 °C), the intensity sharply decreased at durations over 3 hours. This decay was accompanied by appearance of another similar peak (NBP′), which had a peak frequency two orders higher than that of NBP. These peaks had comparable intensity. We attribute NBP and NBP′ to coherent and incoherent ε-carbides, respectively. We produced a model that attributes the relaxation peaks to reorientations of extra carbon pairs in the ε-carbide. The extraordinary values of the Arrhenius parameters may be interpreted by using this model. Based on these results, we assert that mechanical spectroscopy can detect the coherent-incoherent transition in carbon steels. This method will be powerful in studying problems related to the coherency in carbon steels. © 2016, The Minerals, Metals & Materials Society and ASM International. Source

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

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

Ramesh Kumar V.,Center for Nonlinear Science | Radha R.,Center for Nonlinear Science | Wadati M.,Tokyo University of Science
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2010

We investigate the coupled Gross-Pitaevskii equation describing the dynamics of two hyperfine states of Bose-Einstein condensates and deduce the integrability condition for the propagation of bright vector solitons. We show how the transient trap and scattering length can be suitably tailored to bring about fascinating collisional dynamics of vector solitons. © 2010 Elsevier B.V. All rights reserved. Source

De Felice A.,Tokyo University of Science | Tanaka T.,Kyoto University
Progress of Theoretical Physics | Year: 2010

The study of linear perturbation theory for general functions of the Ricci and Gauss-Bonnet scalars is carried out over an empty anisotropic universe, i.e., the Kasner-type background, in order to show that an anisotropic background in general has ghost degrees of freedom, which are absent on Friedmann-Lemaitre-Robertson-Walker (FLRVV) backgrounds. The study of the scalar perturbation reveals that on this background the number of independent propagating degrees of freedom is four and reduces to three on FLRW backgrounds, as one mode becomes highly massive to decouple from the physical spectrum. When this mode remains physical, there is inevitably a ghost mode. Source

Fujisawa J.-I.,Tokyo University of Science | Fujisawa J.-I.,Japan Science and Technology Agency | Giorgi G.,University of Tokyo
Physical Chemistry Chemical Physics | Year: 2014

Methylviologen lead-iodide perovskite (MVPb2I6) is a self-assembled one-dimensional (1-D) material consisting of lead-iodide nanowires and intervening organic electron-accepting molecules, methylviologen (MV2+). MVPb2I6 characteristically shows optical interfacial charge-transfer (ICT) transitions from the lead-iodide nanowire to MV2+ in the visible region and unique ambipolar photoconductivity, in which electrons are transported through the three-dimensional (3-D) organic network and holes along the 1-D lead-iodide nanowire. In this work, we theoretically study the electronic band-structure and photocarrier properties of MVPb2I6 by density functional theory (DFT) calculations. Our results clearly confirm the experimentally reported type-II band alignment, whose valence band mainly consists of 5p (I) orbitals of the lead-iodide nanowires and the conduction band of the lowest unoccupied molecular orbital of MV2+. The DFT calculation also reveals weak charge-transfer interactions between the lead-iodide nanowires and MV2+. In addition, the electronic distributions of the valence and conduction bands indicate the 3-D transport of electrons and 1-D transport of holes, supporting the reported experimental result. This journal is © the Partner Organisations 2014. Source

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

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

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

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

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

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

Hamada M.,Tokyo University of Science | Hamada M.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Computational Biology | Year: 2012

A base-pairing probability matrix (BPPM) stores the probabilities for every possible base pair in an RNA sequence and has been used in many algorithms in RNA informatics (e.g., RNA secondary structure prediction and motif search). In this study, we propose a novel algorithm to perform iterative updates of a given BPPM, satisfying marginal probability constraints that are (approximately) given by recently developed biochemical experiments, such as SHAPE, PAR, and FragSeq. The method is easily implemented and is applicable to common models for RNA secondary structures, such as energy-based or machine-learning-based models. In this article, we focus mainly on the details of the algorithms, although preliminary computational experiments will also be presented. © 2012 Mary Ann Liebert, Inc. Source

Shimizu T.,Kochi University | Azuma T.,Tokyo University of Science
Journal of Immunological Methods | Year: 2015

We developed a method to detect and isolate plasma cells that produce antigen-specific antibodies. An affinity matrix of hapten was constructed on a cell surface, and subsequent incubation allowed cells to secrete antibodies. Anti-hapten antibodies preferentially bound to the affinity matrix on the cells from which they were secreted. We showed that the combination of surface biotinylation and streptavidin which was conjugated with a high valence of hapten was suitable for sensitive detection of antibody binding. Using this protocol, anti-hapten plasma cells from immunized mouse spleen were detected and enriched by flow cytometry. This method allows for isolation of intact plasma cells according to the antibody specificity and may be useful for highly efficient and precise analysis of an antibody repertoire. © 2015 Elsevier B.V. Source

Kunisawa T.,Tokyo University of Science
International Journal of Systematic and Evolutionary Microbiology | Year: 2015

The class Clostridia in the phylum Firmicutes includes a very heterogeneous assemblage of bacteria. Their evolutionary relationships are not well established; revisions of their phylogenetic placements based on comparative studies of 16S rRNA gene sequences are in progress as genome sequence information accumulates. In this work, phylogenetic trees were reconstructed based on 21 concatenated ribosomal protein sequences using Bayesian and maximum-likelihood methods. Both trees consistently indicate that the Halanaerobiales is a deeply branching order among the class Clostridia. The rest of the Clostridia species are grouped into 10 monophyletic clusters, most of which are comprised of two or three orders and families according to the current Clostridial taxonomy. The maximum-likelihood tree placed Coprothermobacter proteolyticus and Thermodesulfobium narugense in the class Clostridia in accordance with the current taxonomy, in which these two bacteria are assigned to the family Thermodesulfobiaceae. However, the Bayesian tree placed these two bacteria at the boundary between the Firmicutes and Actinobacteria. A gene arrangement that is present uniquely in the Firmicutes species was identified. Both Coprothermobacter proteolyticus and Thermodesulfobium narugense do not have this arrangement characteristic of the Firmicutes. On the basis of the Bayesian tree and gene arrangement comparison, it is suggested that Coprothermobacter proteolyticus and Thermodesulfobium narugense should be placed outside the phylum Firmicutes. © 2015 IUMS. Source

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

A new variational principle of steady states is found by introducing an integrated type of energy dissipation (or entropy production) instead of instantaneous energy dissipation. This new principle is valid both in linear and nonlinear transport phenomena. Prigogine's dream has now been realized by this new general principle of minimum "integrated" entropy production (or energy dissipation). This new principle does not contradict with the Onsager-Prigogine principle of minimum instantaneous entropy production in the linear regime, but it is conceptually different from the latter which does not hold in the nonlinear regime. Applications of this theory to electric conduction, heat conduction, particle diffusion and chemical reactions are presented. The irreversibility (or positive entropy production) and long time tail problem in Kubo's formula are also discussed in the Introduction and last section. This constitutes the complementary explanation of our theory of entropy production given in the previous papers (M. Suzuki, Physica A 390 (2011) 1904 and M. Suzuki, Physica A 391 (2012) 1074) and has given the motivation of the present investigation of variational principle. © 2012 Elsevier B.V. All rights reserved. Source

Drerup M.M.,University of Munster | Schlucking K.,University of Munster | Hashimoto K.,University of Munster | Manishankar P.,University of Munster | And 3 more authors.
Molecular Plant | Year: 2013

Stimulus-specific accumulation of second messengers like reactive oxygen species (ROS) and Ca2+ are central to many signaling and regulation processes in plants. However, mechanisms that govern the reciprocal interrelation of Ca2+ and ROS signaling are only beginning to emerge. NADPH oxidases of the respiratory burst oxidase homolog (RBOH) family are critical components contributing to the generation of ROS while Calcineurin B-like (CBL) Ca2+ sensor proteins together with their interacting kinases (CIPKs) have been shown to function in many Ca2+- signaling processes. In this study, we identify direct functional interactions between both signaling systems. We report that the CBL-interacting protein kinase CIPK26 specifically interacts with the N-terminal domain of RBOHF in yeast two-hybrid analyses and with the full-length RBOHF protein in plant cells. In addition, CIPK26 phosphorylates RBOHF in vitro and co-expression of either CBL1 or CBL9 with CIPK26 strongly enhances ROS production by RBOHF in HEK293T cells. Together, these findings identify a direct interconnection between CBL-CIPK-mediated Ca2+ signaling and ROS signaling in plants and provide evidence for a synergistic activation of the NADPH oxidase RBOHF by direct Ca2+-binding to its EF-hands and Ca2+-induced phosphorylation by CBL1/9-CIPK26 complexes. © 2013 The Author. Source

Miyano M.,Tokyo University of Science
Journal of agricultural and food chemistry | Year: 2010

A new device for evaluating the continuity of taste was developed with the use of surface plasmon resonance (SPR). The model of lingual cells was constructed with liposomes immobilized onto an L1 sensor chip for SPR. Using this device, we classified food components into three categories according to the sensorgram pattern and residual ratio on lipid bilayer. Samples in group A strongly interacted with lipid bilayer, those in group B poorly interacted, and those in group C belong to neither group A nor group B. Sweet proteins and gymnemic acids that prolonged sweet perception were categorized in group A. Almost all the carbohydrates investigated and aspartame, of which the taste perception does not continue, belonged to group B. This device made it possible to detect the interaction with lipid bilayer and dissected the mechanism of taste continuity. Source

Hirata S.,Tokyo Institute of Technology | Totani K.,Tokyo University of Agriculture and Technology | Zhang J.,Georgia Institute of Technology | Yamashita T.,Tokyo University of Science | And 4 more authors.
Advanced Functional Materials | Year: 2013

Persistent emission with a long lifetime (>1 s) from organic materials can only be observed at a low temperature, because of the significant nonradiative deactivation pathway that occurs at room-temperature (RT). If organic materials with persistent RT emission in air could be developed, they could potentially be utilized for a variety of applications. Here, organic host-guest materials with efficient persistent RT phosphorescence (RTP) are developed by minimizing the nonradiative deactivation pathway of triplet excitons. The nonradiative deactivation pathway is dependent on both nonradiative deactivation of the guest and quenching by diffusional motion of the host. The rigidity and oxygen barrier properties of the steroidal compound used as the host suppressed the quenching, and the aromatic hydrocarbon used as the guest is highly deuterated to minimize nonradiative deactivation of the guest. Red-green-blue persistent RTP with a lifetime >1 s and a quantum yield >10% in air is realized for a pure organic material. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Nagasawa H.,Tokyo University of Science
Frontiers in Bioscience - Elite | Year: 2012

Crustaceans have a rigid exoskeleton, which is made of a layered cuticle, covering the soft body parts for protection from conspecific competitors and/or interspecific predators. Calcium carbonate adds rigidity to the crustacean cuticle, which consequently means that growth only occur at each molt. The current study presents a review of existing literature on crustacean exoskeleton cuticle physiology and biochemistry in relation to the molting process with special reference to calcification. As a result, research matter where knowledge remains limited has been identified during the molting process, including 1) whether the same or different epithelial cells are responsible for the decomposition and/or reconstruction of chitin and proteins, 2) how calcium carbonate levels are regulated at the cellular level during transfer between the cuticle and body organs, and 3) what factors maintain the amorphous state of calcium carbonate following deposition in the exoskeleton and temporary storage organs. The identification of these areas of focus provides a basis on which targeted future research may be developed, and potentially applied to other invertebrate or even vertebrate processes. Source

He D.,CAS Shanghai Institutes for Biological Sciences | He D.,Johns Hopkins University | Liu Z.-P.,CAS Shanghai Institutes for Biological Sciences | Chen L.,CAS Shanghai Institutes for Biological Sciences | Chen L.,Tokyo University of Science
BMC Genomics | Year: 2011

Background: The incidence of congenital heart disease (CHD) is continuously increasing among infants born alive nowadays, making it one of the leading causes of infant morbidity worldwide. Various studies suggest that both genetic and environmental factors lead to CHD, and therefore identifying its candidate genes and disease-markers has been one of the central topics in CHD research. By using the high-throughput genomic data of CHD which are available recently, network-based methods provide powerful alternatives of systematic analysis of complex diseases and identification of dysfunctional modules and candidate disease genes.Results: In this paper, by modeling the information flow from source disease genes to targets of differentially expressed genes via a context-specific protein-protein interaction network, we extracted dysfunctional modules which were then validated by various types of measurements and independent datasets. Network topology analysis of these modules revealed major and auxiliary pathways and cellular processes in CHD, demonstrating the biological usefulness of the identified modules. We also prioritized a list of candidate CHD genes from these modules using a guilt-by-association approach, which are well supported by various kinds of literature and experimental evidence.Conclusions: We provided a network-based analysis to detect dysfunctional modules and disease genes of CHD by modeling the information transmission from source disease genes to targets of differentially expressed genes. Our method resulted in 12 modules from the constructed CHD subnetwork. We further identified and prioritized candidate disease genes of CHD from these dysfunctional modules. In conclusion, module analysis not only revealed several important findings with regard to the underlying molecular mechanisms of CHD, but also suggested the distinct network properties of causal disease genes which lead to identification of candidate CHD genes. © 2011 He et al; licensee BioMed Central Ltd. Source

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

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

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

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

Oka Y.,Yokohama National University | Matsuyama K.,Tokyo University of Science
Fire Safety Journal | Year: 2013

In this study, empirical formulae previously derived for describing the decrease in temperature rise, the decrease in velocity, the thermal boundary layer thickness, the momentum boundary layer thickness, the Gaussian thermal thickness, and the Gaussian momentum thickness of a ceiling jet flowing upward along the steepest run of an inclined ceiling were applied to a full-scale scenario. The coefficients in these formulae were determined through a series of pool fire tests conducted using a flat, unconfined model ceiling with dimensions of 2.5 m×3.0 m, and fixed ceiling clearance of 1.0 m. To verify the applicability of the developed formulae to actual fires, another series of pool fire tests were conducted using a flat, unconfined full-scale ceiling with dimensions of 7.0 m×14.0 m and a maximum ceiling clearance of 3.0 m. The proposed formulae were confirmed to be applicable to a full-scale scenario and to describe the ceiling jet flow accurately. © 2013 Published by Elsevier Ltd. Source

This paper presents an evaluation of global warming mitigation options based on scenarios from the Asian Modeling Exercise. Using an extended version of the integrated assessment model MARIA-23 (Multiregional Approach for Resource and Industry Allocation), we analyze nuclear fuel recycling options, carbon capture and storage technologies (CCS), and biomass utilization. To assess the potential implications of decreased social acceptance of nuclear power in the wake of the Fukushima nuclear accident, additional scenarios including a nuclear power expansion limitation, are analyzed. We also evaluate MARIA-23 model simulation estimates of long-term contributions and interrelationships among nuclear power, biomass, and CCS. Finally, potential costs of nuclear limitation under carbon control policies are assessed. The simulation results in this paper suggest the following: (1) under the reference scenario, global GDP losses in climate limitation scenarios range from 1.3% per year to 3.9% per year in 2060, rising to between 3.5% per year and 4.5% per year in 2100; (2) the use of nuclear fuel reprocessing technologies increase rapidly in all carbon control policy scenarios; (3) under a scenario where the price of CO2 is $30 and nuclear power expansion is strictly limited, GDP losses increase significantly-from 4.5% per year to 6.4% per year by 2100; (4) nuclear power and CCS are substitute mitigation technologies. With nuclear power technology available CCS deployment reaches approximately 15,000Mt-CO2 per year by 2010; without a nuclear power option, CCS deployment rises to more than 80,000Mt-CO2 per year; and (5) biomass utilization cannot fully compensate for limitations to nuclear power expansion in policy scenarios. In addition to examining the role of these three technologies on global scales, we report results for several major Asian regions, namely Japan, China, and India. China tends to deploy nuclear power (if available) in response to rapidly growing power demands, in all scenarios while India tends to rely less on nuclear power. The potential cost of nuclear power limitation under global warming mitigation in Japan is estimated be significantly higher than in China or India. © 2012 Elsevier B.V. Source

Ohshima H.,Tokyo University of Science
Advances in Colloid and Interface Science | Year: 2015

Theories of the electrostatic interaction between two soft particles (i.e., particles covered with an ion-penetrable surface layer of polyelectrolytes) in an electrolyte solution are reviewed. Interactions of soft particles after contact of their surface layers are particularly discussed. Interaction in a salt-free medium and the discrete-charge effect are also treated. © 2015 Elsevier B.V. Source

Endo K.,Tokyo University of Science
Russian Journal of Physical Chemistry A | Year: 2016

In the Auger electron spectra (AES) simulations, we define theoretical modified kinetic energies of AES in the density functional theory (DFT) calculations. The modified kinetic energies correspond to two final-state holes at the ground state and at the transition-state in DFT calculations, respectively. This method is applied to simulate Auger electron spectra (AES) of 2nd periodic atom (Li, Be, B, C, N, O, F)-involving substances (LiF, beryllium, boron, graphite, GaN, SiO2, PTFE) by deMon DFT calculations using the model molecules of the unit cell. Experimental KVV (valence band electrons can fill K-shell core holes or be emitted during KVV-type transitions) AES of the (Li, O) atoms in the substances agree considerably well with simulation of AES obtained with the maximum kinetic energies of the atoms, while, for AES of LiF, and PTFE substance, the experimental F KVV AES is almost in accordance with the spectra from the transitionstate kinetic energy calculations. © 2016 Pleiades Publishing, Ltd. Source

Saito K.,Tokyo University of Science
AIP Conference Proceedings | Year: 2010

We extend the quark-meson coupling (QMC) model to incorporate chiral symmetry. The relationship between the QMC model and chiral perturbation theory is also discussed. The nuclear central potential is modified by the effect of internal structure of the nucleon. © 2010 American Institute of Physics. Source

Ohta H.,Tokyo University of Science
Journal of Physics A: Mathematical and Theoretical | Year: 2010

The Glauber dynamics of a bond-diluted Ising model on a Bethe lattice (a random graph with fixed connectivity) is investigated by an approximate theory which provides exact results for equilibrium properties. The timedependent solutions of the dynamical system derived by this method are in good agreement with the results obtained by Monte Carlo simulations in almost all situations. Furthermore, the derived dynamical system exhibits a remarkable phenomenon that the magnetization shows multi-step relaxations at intermediate time scales in a low-temperature part of the Griffiths phase without bond percolation clusters. © 2010 IOP Publishing Ltd. Source

Homma Y.,Tokyo University of Science
Catalysts | Year: 2014

Gold nanoparticles have been proven to act as efficient catalysts for chemical reactions, such as oxidation and hydrogen production. In this review we focus on a different aspect of the catalysis of gold nanoparticles; single-walled carbon nanotube (SWCNT) synthesis. This is not a traditional meaning of catalytic reaction, but SWCNTs cannot be synthesized without nanoparticles. Previously, gold was considered as unsuitable metal species as the catalyst of SWCNT synthesis. However, gold nanoparticles with diameters smaller than 5 nm were found to effectively produce SWCNTs. We discuss the catalysis of gold and related metals for SWCNT synthesis in comparison with conventional catalysts, such as iron, cobalt, and nickel. © 2014 by the authors; licensee MDPI, Basel, Switzerland. Source

Spirocyclic scaffolds are embedded in many biologically active natural compounds, including candidates for medicines, perfumes and agricultural chemicals. Therefore, the development of efficient synthetic methods directed at those structures is strongly in demand. To this end, we have recently developed synthetic methodologies for two different spirocyclic frameworks, spiro[4.5]decanes and spirocyclic oxindoles, based on the Claisen rearrangement. We have developed the Claisen rearrangement protocol by which bicyclic 2-(alkenyl)dihydropyrans with functionality at the 4-position can be transformed into spiro[4.5]decanes in good-to-excellent yields with excellent stereoselectivities. We applied this method to a concise total synthesis of several biologically active spirocyclic sesquiterpenes. Related Claisen rearrangement in alkenyl pyranoindole systems can also be achieved. Thus, a one-pot intramolecular Ullmann coupling (IUC)/Claisen rearrangement sequence from 2-iodoindoles was found to provide spirocyclic oxindoles in good yields with excellent stereoselectivities. We applied this sequence to the synthesis of pyrrolidinoindoline alkaloids. © Georg Thieme Verlag Stuttgart · New York. Source

Sugimoto K.,Kyoto University | Arimura G.-I.,Tokyo University of Science
Plant Signaling and Behavior | Year: 2013

Intact maize plants prime for defensive action against herbivory in response to herbivore-induced plant volatiles (hiPVs) emitted from caterpillar-infested conspecifc plants. the recent research showed that the primed defense in receiver plants that had been exposed to hiPVs was maintained for at least 5 d after exposure. herbivory triggered the receiver plants to enhance the expression of a defense gene for trypsin inhibitor (ti). at the upstream sequence of a TI gene, non-methylated cytosine residues were observed in the genome of hiPV-exposed plants more frequently than in that of healthy plant volatile-exposed plants. these fndings provide an innovative mechanism for the memory of hiPV-mediated habituation for plant defense. this mechanism and further innovations for priming of defenses via plant communications will contribute to the development of plant volatile-based pest management methods in agriculture and horticulture. © 2013 Landes Bioscience. Source

Kaneko K.,Tokyo University of Science
Engineering Fracture Mechanics | Year: 2015

In this study, the torsion pin-test method that as originally presented by the author was applied to investigate the shearing delamination strength of thermal barrier coatings. By comparing the corresponding FEM analysis to the obtained experimental results, finally, the delamination criteria for the thermal barrier coating before and after heating were found to be expressed using the stress intensity factor and the stress gradient of the shear singular stress distributions around the interface edge between the top-coat and the bond coat. © 2015 Elsevier Ltd. Source

Matous P.,University of Tokyo | Todo Y.,University of Tokyo | Mojo D.,Tokyo University of Science
International Journal of Agricultural Sustainability | Year: 2013

This article analyses roles of social and extension networks in adoption of resource-conserving practices among Ethiopian farmers. We gathered data from 297 randomly sampled households on their agricultural practices, social networks, access to the extension, and geographical location. After examining general determinants of practising resource-conserving agriculture, we employ a two-stage regression with full-maximum likelihood correction for selection bias to establish the roles of general social networks and external professionals in acceptance of conservation techniques. In accordance with previous research, probit regression in the first stage shows that the access to extension increases with farmers' wealth and the size of their personal networks, and decreases with the distance of their households from village centres. However, after accounting for this unequal access to extension, the second-stage linear regression shows that regardless of education, wealth or geographical location, those whose religion and ethnicity match with their agent, report learning more about conservation from extension sources. Furthermore, farmers who are socially well connected within the community tend to be less receptive to agents' recommendations regarding resource conservation. Dissemination policy of conservation agriculture should consider the ethnic and religious affinity between farmers and their extension agents. It also needs to pay more attention to socially and geographically isolated individuals. © 2013 © 2013 Taylor & Francis. Source

This paper reviews the formation mechanism and chemical safety of nonintentional chemical substances (NICS) present in chlorine-treated water containing organic contaminants. Undesirable compounds, i.e., NICS, may be formed under certain conditions when chlorine reacts with organic matter. The rate and extent of chlorine consumption with organics are strongly dependent on their chemical structures, particularly whether double bonds or sulfur and nitrogen atoms occur in the molecules. Organothiophosphorus pesticides (P=S type) are easily oxidized to their phosphorus compounds (P=O type) in chlorinated water containing HOCl as little as 0.5 mg/l, resulting in an increase in cholinesterase-inhibitory activity. Chlorination of phenols in water also produces a series of highly chlorinated compounds, including chlorophenols, chloroquinones, chlorinated carboxylic acids, and polychlorinated phenoxyphenols (PCPPs). In some of these chloroquinones, 2,6- dichloroalkylsemiquinones exhibit a strong mutagenic response as do positive controls used in the Ames test. 2-Phenoxyphenols in these PCPPs are particularly interesting, as they are present in the chlorine-treated phenol solution and they are also precursors (predioxins) of the highly toxic chlorinated dioxins. Polynuclear aromatic hydrocarbons (PAHs) were found to undergo chemical changes due to hypochlorite reactions to give chloro-substituted PAHs, oxygenated (quinones) and hydroxylated (phenols) compounds, but they exhibit a lower mutagenic response. In addition, field work was performed in river water and drinking water to obtain information on chemical distribution and their safety, and the results are compared with those obtained in the model chlorination experiments. © 2010 The Pharmaceutical Society of Japan. Source

Sugiura K.,The Jackson Laboratory | Sugiura K.,Tokyo University of Science | Su Y.-Q.,The Jackson Laboratory | Eppig J.J.,The Jackson Laboratory
Biology of Reproduction | Year: 2010

Bone morphogenetic protein 6 (BMP6) is a transforming growth factor beta superfamily member produced by mammalian oocytes as well as other cell types. Despite well-characterized effects of recombinant BMP6 on granulosa cells in vitro, the function of BMP6 in vivo has been ill-defined. Therefore, the effects of genetic deletion of the Bmp6 gene on female mouse fertility were assessed. The mean litter size of Bmp6-/- females was reduced by 22% (P < 0.05) compared to Bmp6+/+ controls. Not only did Bmp6-/- females naturally ovulate 24% fewer eggs, but competence of in vitro-matured oocytes to complete preimplantation development after fertilization in vitro was decreased by 50%. No apparent effect of Bmp6 deletion on either the morphology or the dynamics of follicular development was apparent. Nevertheless, levels of luteinizing hormone (LH)/ human chorionic gonadotropin (hCG)-induced transcripts, which encode proteins required for cumulus expansion (HAS2, PTGS2, PTX3, and TNFAIP6), and of epidermal growth factor-like peptides (AREG, BTC, and EREG) were lower in Bmp6-/- mice than in controls after administration of a reduced dose of hCG (1 IU) in vivo. LH receptor (Lhcgr) transcript levels were not significantly lower in Bmp6-/- granulosa cells, suggesting that BMP6 is required for processes downstream of LH receptors. To assess whether another oocyte-derived BMP, BMP15, could have BMP6-redundant functions in vivo, the fertility of Bmp15/Bmp6 double mutants was assessed. Fertility was not significantly reduced in double-homozygous mutants compared with that in double-heterozygous controls. Therefore, BMP6 promotes normal fertility in female mice, at least in part, by enabling appropriate responses to LH and normal oocyte quality. Thus, Bmp6 probably is part of the complex genetic network that determines female fertility. © 2010 by the Society for the Study of Reproduction, Inc. Source

Nakazato K.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

The spectrum and event rate of supernova relic neutrinos are calculated, taking into account the dependence on the time it takes for the shock wave in supernova cores to revive. The shock revival time should depend on the still unknown explosion mechanism of collapse-driven supernovae. The contribution of black-hole-forming failed supernovae is also considered. The total event rate is higher for models with a longer shock revival time and/or a failed-supernova contribution. The hardness of the spectrum does not strongly depend on the shock revival time, but the spectrum becomes hard owing to the failed supernovae. Therefore, the shock-revival-time dependence of supernova relic neutrinos has different systematics from the fractions of failed supernovae. © 2013 American Physical Society. Source

Okada H.,Kyoto University | Totani T.,Kyoto University | Totani T.,University of Tokyo | Tsujikawa S.,Tokyo University of Science
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

The growth rate of matter density perturbations has been measured from redshift-space distortion (RSD) in the galaxy power spectrum. We constrain the model parameter space for representative modified gravity models to explain the dark energy problem, by using the recent data of fm(z) σ8(z) at the redshifts z=0.06-0.8 measured by WiggleZ, SDSS LRG, BOSS, and 6dFGRS. We first test the Hu-Sawicki's f(R) dark energy model, and find that only the parameter region close to the standard Λ cold dark matter model is allowed (λ>12 and 5 for n=1.5 and 2, respectively, at 95% C.L.). We then investigate the covariant Galileon model with a de Sitter attractor and show that the parameter space consistent with the background expansion history is excluded by the RSD data at more than 8σ because of the too large growth rate predicted by the theory. Finally, we consider the extended Galileon scenario, and we find that, in contrast to the covariant Galileon, there is a model parameter space for a tracker solution that is consistent with the RSD data within a 2σ level. © 2013 American Physical Society. Source

Tsutani K.,Tokyo University of Science
Nippon rinsho. Japanese journal of clinical medicine | Year: 2010

Various molecular target drugs are developed in recent era in Japan, especially for treatment of cancer, rheumatoid arthritis and other diseases. Although they are much more effective compared to previous drugs, their costs are much more expensive. Thus, pharmacoeconomic analysis in which we evaluate their efficiency, would be highly needed. When we take pharmacoeconomic analyses, we need to assess both costs and health outcomes. In addition, we must compare cost-effectiveness of new interventions and control. To estimate costs of each intervention, not only direct medical costs, but direct non-medical costs (e.g. transportation costs, caregiving costs, house--modification costs) and indirect costs, or productivity losses should be separately calculated and presented. To evaluate efficiencies of anti-rheumatoid biologic agent in Japan, we started to collaborate with large-scale cohort of patient with rheumatoid arthritis in Japan, IORRA cohort in Tokyo Women's Medical University. With this data, we are taking various pharmacoeconomic analysis. Source

Yamashita T.,Tokyo University of Science | Peng Y.,James Franck Institute | Knight C.,Argonne National Laboratory | Voth G.A.,James Franck Institute | Voth G.A.,Argonne National Laboratory
Journal of Chemical Theory and Computation | Year: 2012

It is a computationally demanding task to explicitly simulate the electronic degrees of freedom in a system to observe the chemical transformations of interest, while at the same time sampling the time and length scales required to converge statistical properties and thus reduce artifacts due to initial conditions, finite-size effects, and limited sampling. One solution that significantly reduces the computational expense consists of molecular models in which effective interactions between particles govern the dynamics of the system. If the interaction potentials in these models are developed to reproduce calculated properties from electronic structure calculations and/or ab initio molecular dynamics simulations, then one can calculate accurate properties at a fraction of the computational cost. Multiconfigurational algorithms model the system as a linear combination of several chemical bonding topologies to simulate chemical reactions, also sometimes referred to as "multistate". These algorithms typically utilize energy and force calculations already found in popular molecular dynamics software packages, thus facilitating their implementation without significant changes to the structure of the code. However, the evaluation of energies and forces for several bonding topologies per simulation step can lead to poor computational efficiency if redundancy is not efficiently removed, particularly with respect to the calculation of long-ranged Coulombic interactions. This paper presents accurate approximations (effective long-range interaction and resulting hybrid methods) and multiple-program parallelization strategies for the efficient calculation of electrostatic interactions in reactive molecular simulations. © 2012 American Chemical Society. Source

Nakano Y.,Tokyo University of Science
Ambio | Year: 2012

The primary targets of our project are to drastically improve the photovoltaic conversion efficiency and to develop new energy storage and delivery technologies. Our approach to obtain an efficiency over 40% starts from the improvement of III-V multi-junction solar cells by introducing a novel material for each cell realizing an ideal combination of bandgaps and lattice-matching. Further improvement incorporates quantum structures such as stacked quantum wells and quantum dots, which allow higher degree of freedom in the design of the bandgap and the lattice strain. Highly controlled arrangement of either quantum dots or quantum wells permits the coupling of the wavefunctions, and thus forms intermediate bands in the bandgap of a host material, which allows multiple photon absorption theoretically leading to a conversion efficiency exceeding 50%. In addition to such improvements, microfabrication technology for the integrated high-efficiency cells and the development of novel material systems that realizes high efficiency and low cost at the same time are investigated. © Royal Swedish Academy of Sciences 2012. Source

Takahashi K.,Tokyo University of Science
Journal of vision | Year: 2011

We can easily recognize human movements from very limited visual information (biological motion perception). The present study investigated how upper and lower body areas contribute to direction discrimination of a point-light (PL) walker. Observers judged the direction that the PL walker was facing. The walker performed either normal walking or hakobi, a walking style used in traditional Japanese performing arts, in which the amount of the local motion of extremities is much smaller than that in normal walking. Either the upper, lower, or full body of the PL walker was presented. Discrimination performance was found to be better for the lower body than for the upper body. We also found that discrimination performance for the lower body was affected by walking style and/or the amount of local motion signals. Additional eye movement analyses indicated that the observers initially inspected the region corresponding to the upper body, and then the gaze shifted toward the lower body. This held true even when the upper body was absent. We conjectured that the upper body subserved to localize the PL walker and the lower body to discriminate walking direction. We concluded that the upper and lower bodies play different roles in direction discrimination of a PL walker. Source

We investigated and clarified the superstructures formed by tetrahedra in the bcc lattice within the framework of second-order transitions. Compliance with both the Landau and Lifshitz conditions was investigated for all possible superstructures and, based on this, we demonstrate that bcc crystals that contain tetrahedra at an inversion center can exhibit a variety of second-order transitions, which are regarded as a new type of diffusionless order-disorder transition with antiferroic orientational orders. Finally, we show that the transition gives rise to a new glassy state. Breaking of the local inversion symmetry may lead to a new orientational glass, which is reminiscent of spin glasses in magnetism. © 2015 IOP Publishing Ltd. Source

Iwai N.,Tokyo University of Science
Journal of Zoology | Year: 2013

Frogs and toads normally have four toes on the forelimbs and five on the hindlimbs. An exception is the Otton frog Babina subaspera, which has regained the pseudothumbs. The morphology and use of pseudothumbs in Otton frogs were compared between the sexes. The pseudothumbs, which are longer and thicker in males than in females, encase a prepollical spine that occasionally cuts through the tissue as it is projected from the sheath. The males had visible spines and demonstrated a jabbing response more often than did females. Males were observed to use their pseudothumbs in male-male combat over females or breeding nests, as well as during amplexus. There was no evidence that females use their pseudothumbs. It is suggested that pseudothumbs first evolved as an anchor for amplexus, but that they are now used as a weapon in combat as well, giving males higher fitness. The study of pseudothumbs in the Otton frog will facilitate further study of related topics of interest, including extra fingers in vertebrates, self-damaging structures and developmental constraints in the hands. © 2012 The Zoological Society of London. Source

Chen D.H.,Tokyo University of Science
Composite Structures | Year: 2011

The flexural rigidity and torsional rigidity of an open honeycomb were evaluated by analyzing the bending and torsional deformation of cell plates with consideration of the constraint condition on the plate edges. The analysis of torsional rigidity showed that if the deformation of a honeycomb satisfies periodicity conditions, the ratio of Mxy|unit and Myx|unit acting on each unit constituting the honeycomb becomes a specific value to satisfy the continuity condition of displacement. This specific value is obtained using an equation proposed in this study; the value depends only on the geometry of the honeycomb. As a consequence of the necessity that the ratio of Mxy|unit and Myx|unit should become a specific value, if the ratio of torsional load moments M∞ xy-M∞ yx acting on the boundaries is not actually equal to the above-mentioned value, scattering appears near the boundary in the ratio of Mxy|unit and Myx|unit, and the ratio approaches the above-mentioned specific value as the distance from the boundary increases. Therefore, even if the value (M∞ xy-M∞ yx) is kept the same, the scattering of deflection depends on the combination of torsional moments, and becomes smaller as the honeycomb model becomes larger compared with the size of a unit. © 2011 Elsevier Ltd. Source

Gao Z.,School of Advanced Engineering Studies | Zhi C.,Japan International Center for Materials Nanoarchitectonics | Bando Y.,Japan International Center for Materials Nanoarchitectonics | Golberg D.,Japan International Center for Materials Nanoarchitectonics | Serizawa T.,Tokyo University of Science
ACS Applied Materials and Interfaces | Year: 2011

Strong and stable visible-light-emitting boron nitride nanotube (BNNT)/biomolecule nanohybrids were successfully fabricated via noncovalent functionalization of BNNTs with flavin mononucleotides (FMN). Atomic force microscopy showed excellent dispersion of the nanohybrids in aqueous solution. Infrared absorption spectroscopy revealed strong π-π stacking interactions between FMN and BNNT sidewalls. Importantly, the fluorescence spectra revealed that the nanohybrids were highly fluorescent in the visible-light spectral range. Moreover, this fluorescence had unique pH-dependent and thermally stable properties. These nanohybrids might be used to construct novel fluorescence imaging probes that function over a wide pH and temperature range. © 2011 American Chemical Society. Source

Chen D.H.,Tokyo University of Science
Composite Structures | Year: 2011

In this study, the flexural rigidity of a honeycomb consisting of regular hexagonal cells is investigated. It is found that the bending deformation of the honeycomb cannot be evaluated by using the equivalent elastic moduli obtained from the in-plane deformation since the moments acting on inclined walls of honeycomb cell are different for the in-plane deformation and bending deformation. Based on the fact that the inclined wall of the honeycomb is twisted under the condition that the rotation angle in both connection edges is zero in bending deformation, a theoretical technique for calculating the honeycomb flexural rigidity is proposed. In the theoretical analysis, a torsion problem of a thin plate was solved by using the generalized variational principle. The validity of the present analysis is demonstrated by numerical results obtained by the finite element method. © 2010 Elsevier Ltd. Source

Rogers J.M.,University of Cambridge | Rogers J.M.,Tokyo University of Science | Oleinikovas V.,University of Cambridge | Oleinikovas V.,University College London | And 6 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Protein-protein interactions are at the heart of regulatory and signaling processes in the cell. In many interactions, one or both proteins are disordered before association. However, this disorder in the unbound state does not prevent many of these proteins folding to a well-defined, ordered structure in the bound state. Here we examine a typical system, where a small disordered protein (PUMA, p53 upregulated modulator of apoptosis) folds to an α-helix when bound to a groove on the surface of a folded protein (MCL-1, induced myeloid leukemia cell differentiation protein). We follow the association of these proteins using rapid-mixing stopped flow, and examine how the kinetic behavior is perturbed by denaturant and carefully chosen mutations. We demonstrate the utility of methods developed for the study of monomeric protein folding, including β-Tanford values, Leffler α, Ö-value analysis, and coarse-grained simulations, and propose a self-consistent mechanism for binding. Folding of the disordered protein before binding does not appear to be required and few, if any, specific interactions are required to commit to association. The majority of PUMA folding occurs after the transition state, in the presence of MCL-1. We also examine the role of the side chains of folded MCL-1 that make up the binding groove and find that many favor equilibrium binding but, surprisingly, inhibit the association process. Source

Kawai H.,Tokyo University of Science
Bulletin of the Chemical Society of Japan | Year: 2015

This report describes the synthesis and structural features of supramolecular assemblies of s-hydrindacene (1,2,3,5,6,7-hexahydro-s-indacene), such as macrocycles with directionally persistent peripheral functionality, allosteric receptors, adrenaline receptors, and rotaxane molecular shuttles. These hydrindacene-based assemblies also exhibit allostericity due to induced polarization of amides or to entropy-driven switching between the imine and hydrogen bonds. © 2015 The Chemical Society of Japan. Source

Yajima T.,Tokyo University of Science | Nagahama H.,Tohoku University
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2010

A new geometric viewpoint of the Lorenz system is proposed based on a theory of tangent bundle. By introducing the geometrical viewpoints of second order system governed by Euler-Poincaré equation or Lie-Poisson equation, geometrical invariants of the Lorenz system can be obtained. Especially, a torsion tensor as one of geometrical invariants relates to the chaotic behavior characterized by the Rayleigh number, and results from the decomposition from the second order system to the tangent space (state space) and base space (configuration space). © 2010 Elsevier B.V. All rights reserved. Source

Bamba K.,National Tsing Hua University | Geng C.-Q.,National Tsing Hua University | Tsujikawa S.,Tokyo University of Science
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2010

We show that it is possible to obtain a picture of equilibrium thermodynamics on the apparent horizon in the expanding cosmological background for a wide class of modified gravity theories with the Lagrangian density f (R, φ{symbol}, X), where R is the Ricci scalar and X is the kinetic energy of a scalar field φ{symbol}. This comes from a suitable definition of an energy-momentum tensor of the "dark" component that respects to a local energy conservation in the Jordan frame. In this framework the horizon entropy S corresponding to equilibrium thermodynamics is equal to a quarter of the horizon area A in units of gravitational constant G, as in Einstein gravity. For a flat cosmological background with a decreasing Hubble parameter, S globally increases with time, as it happens for viable f (R) inflation and dark energy models. We also show that the equilibrium description in terms of the horizon entropy S is convenient because it takes into account the contribution of both the horizon entropy over(S, ̂) in non-equilibrium thermodynamics and an entropy production term. © 2010 Elsevier B.V. All rights reserved. Source

Tsujikawa S.,Tokyo University of Science
Lecture Notes in Physics | Year: 2010

We review the recent progress for modified gravity models of dark energy - including f(R) gravity, scalar-tensor theories, and braneworld models. In f(R) gravity, where the Lagrangian density f is a function of the Ricci scalar R, the coupling strength between dark energy and non-relativistic matter is of order 1 ( ) in the Einstein frame. Even in this situation it is possible for f(R) models to be consistent with local gravity constraints under the chameleon mechanism, while at the same time satisfying conditions for the cosmological viability. We present a number of viable f(R) models that satisfy cosmological and local gravity constraints. We also study a class of scalar-tensor dark energy models based on Brans-Dicke theory with a scalar-field potential. The action in the Einstein frame can be viewed as a coupled quintessence scenario with a constant coupling Q that is related to a Brans-Dicke parameter via . We show that, even when is of the order of 1, it is possible for these models to be consistent with cosmological and local gravity constraints as long as the field potential is designed in a suitable way. We investigate the evolution of matter density perturbations for f(R) and scalar-tensor models and show that model parameters as well as the strength of the coupling Q can be constrained from matter/CMB power spectra due to the enhanced growth rate of perturbations compared to the ΛCDM model. Finally, we discuss the DGP braneworld model as a candidate for dark energy. While the late-time cosmic acceleration is possible, this model is under strong pressure from joint constraints using the data of SNLS, BAO, and the CMB shift parameter. Moreover, a ghost mode is present for such a self-accelerating universe. Thus the original DGP model is effectively ruled out from observational constraints as well as from the ghost problem. © 2010 Springer-Verlag Berlin Heidelberg. Source

Minoshima K.,Japan National Institute of Advanced Industrial Science and Technology | Arai K.,Japan National Institute of Advanced Industrial Science and Technology | Arai K.,Tokyo University of Science | Inaba H.,Japan National Institute of Advanced Industrial Science and Technology
Optics Express | Year: 2011

Long-path pulse-to-pulse interferometers of two-color frequency combs are developed using fundamental and second harmonics of a mode-locked fiber laser. Interferometric phase difference between two-color frequency combs was precisely measured by stabilizing the fundamental fringe phase by controlling the repetition frequency of the comb, and a stability of 10-10 for 1000 s was achieved in the measurement of an optical path length difference between two wavelengths. In long-term measurements performed for 10 h, results of phase variation of interferometric measurements were highly consistent with the fluctuations in the calculated difference of refractive indices of air at two wavelengths with an accuracy of 10-10. The difference between the measured optical distances corresponding to two wavelengths and the optical distance corresponding to the fundamental wavelength were used in the two-color method; high-accuracy self-correction of the fluctuation of refractive index of air was performed with an uncertainty of 5 × 10-8 for 10-h measurements when the maximum refractive index change was on the order of 10-6. ©2010 Optical Society of America. Source

Sato R.,Tokyo University of Science
Archives of Biochemistry and Biophysics | Year: 2010

Cholesterol is one of the major components of membrane lipids. Adjustment of the membrane cholesterol balance is, therefore, pivotal in the maintenance of cellular homeostasis. Cholesterol biosynthesis and uptake are tightly regulated at the transcriptional level through a negative feedback control. The transcription factor family known as sterol regulatory element-binding proteins (SREBPs) is in charge of this feedback control. In particular, SREBP-2 is activated in a cholesterol-dependent manner, and hence is deeply involved in regulation of the expression of genes closely related to cholesterol metabolism. Sterol metabolites, including cholesterol, 24,25-dihydrolanosterol and oxysterols, strongly participate in the regulation of sterol metabolism via binding to its particular proteins. © 2010 Elsevier Inc. Source

Uchida T.,Public Works Research Institutes | Asano Y.,Tokyo University of Science
Hydrological Processes | Year: 2010

Recent studies have reported that not only water travelling through the soil layer but also emerging from fractured/weathered bedrock, contributes to hillslope runoff from steep wet hillslopes. Therefore, discharge is derived from a variety of hillslope sources. However, data are often lacking about how spatial variability in the water movement in bedrock on hillslopes affects hydrological behaviours in individual catchments because most previous studies have focused on single hillslopes in individual catchments. Therefore, we began by examining spatial variability in the bedrock groundwater contribution to hillslope runoff using a data set from Fudoji (central Japan), which has uniform bedrock geology, soil type and land use. We found that most hillslope runoff within the meso-scale catchment (4-27 km2) was a mixture of water flowing through the soil layer (subsurface flow) and water emerging from bedrock (groundwater flow). The depths of water sources (flowpath) that contributed to hillslope runoff varied greatly, even though the catchment had uniform bedrock geology, soil type and land use. Furthermore, we examined how bedrock groundwater affected hydrological behaviour in the catchment and found that the streamflow of first-to sixth-order streams were a mixture of water from the soil layer and bedrock groundwater, indicating that the end member of streamflow was the same as hillslope runoff in terms of the depth of flowpath. We also found that the mixing ratio of water from the soil layer and bedrock groundwater in first-order streams exhibited a significant spatial variation, but that the mixing ratio in third-to sixth-order streams did not. This indicates that depth of flowpath is a key component for describing hillslope and catchment hydrological responses. Copyright © 2010 John Wiley & Sons, Ltd. Source

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. Source

Wakabayashi I.,Tokyo University of Science
International Conference on Advanced Communication Technology, ICACT | Year: 2010

Timing jitter in M-PAM, M-ASK, and M2-QAM with AWGN is calculated for a cosine roll-off bandlimiting scheme applying a newly derived closed-form representation in the frequency domain of the jitter power spectral density (jitter PSD). Jitter PSD consists of SS, SN, and NN components. Each component of jitter variance is obtained by integrating the corresponding jitter PSD over a finite frequency domain in a bandlimiting scheme. The total jitter variance is obtained as the sum of the three components. The dependencies of the calculated jitter variance on the system parameters, i.e., SNR, ρ, alphabet size, M, transmission scheme, PLL normalized noise bandwidth, biL and roll-off factor, α, are evaluated. Specifically, the SS component increases with increasing M. However, this increase is limited withina finite range.Since the SN and NN components are independent of M, the dependence of the total jitter variance on M is small. At low and medium SNRs, the total jitter variance is independent of M. At high SNRs, the total jitter variance increases with increasing M, but the increase is rather small when M is greater than 4. Calculated values of the SS, SN, and NN components of jitter variance in QAM are tabulated. The numerical values in QAM can be used to determinethe numerical values in PAM and ASK. Source

Emeline A.V.,Saint Petersburg State University | Zhang X.,Northeast Normal University | Murakami T.,Kanagawa Academy Of Science And Technology | Fujishima A.,Tokyo University of Science
Journal of Hazardous Materials | Year: 2012

Photodegradation of phenol and 4-chlorophenol over six different TiO 2 samples was tested in order to establish whether an interconnection between the activity and selectivity of photocatalysts exists. The obtained experimental data were analyzed using correlation analysis. Some correlations between the activity in phenol(s) photodegradation and selectivity toward formation of primary intermediate products were established. The type of correlations depends on the type of studied photoreactions. The discussion of the observed correlations between the activity and selectivity of photocatalysts is given in terms of the difference of surface concentrations of electrons and holes and corresponding surface active sites which might be dependent on the types of dominating surface faces. On the basis of the obtained results of correlation analysis it was assumed that a higher activity of photocatalysts could be achieved provided that both reduction and oxidation reaction pathways occur with equally high efficiency. © 2011 Elsevier B.V. Source

Nakamula A.,Kitasato University | Sawado N.,Tokyo University of Science
Nuclear Physics B | Year: 2013

The Nahm data of periodic instantons, often called calorons, with spatial CN-symmetries are considered, by applying Sutcliffe's ansatz for the monopoles with CN-symmetries. The bulk data of calorons are shown to enjoy the periodic Toda lattice, and the solutions are given in terms of elliptic theta functions. The case of N=3 calorons are investigated in detail. It is found that the "scale parameters" of these calorons have upper bounds in their values, so that they do not have the large scale, or monopole, limits. The instanton limit of the C3-symmetric caloron is obtained. © 2012 Elsevier B.V. Source

Ohshima H.,Tokyo University of Science
Soft Matter | Year: 2012

The stability of a suspension of colloidal particles is determined by the interparticle electrostatic interaction, which in turn depends on the particle surface potential. The surface potential or charge of a charged colloidal particle can be evaluated by measuring its electrophoretic mobility. In the present article we focus on soft particles, that is, hard particles covered with an ion-penetrable surface layer of polyelectrolytes and provide various approximate analytic expressions for the electrostatic interaction energy between soft particles and for the electrophoretic mobility of soft particles. These expressions, which depend on the Donnan potential in the surface layer, are quite different from those for hard particles without surface structures. © 2012 The Royal Society of Chemistry. Source

Matsuda F.,Nagoya University | Inoue N.,Nagoya University | Manabe N.,Tokyo University of Science | Ohkura S.,Nagoya University
Journal of Reproduction and Development | Year: 2012

The mammalian ovary is an extremely dynamic organ in which a large majority of follicles are effectively eliminated throughout their reproductive life. Due to the numerous efforts of researchers, mechanisms regulating follicular growth and atresia in mammalian ovaries have been clarified, not only their systemic regulation by hormones (gonadotropins) but also their intraovarian regulation by gonadal steroids, growth factors, cytokines and intracellular proteins. Granulosa cells in particular have been demonstrated to play a major role in deciding the fate of follicles, serving molecules that are essential for follicular growth and maintenance as well as killing themselves by an apoptotic process that results in follicular atresia. In this review, we discuss the factors that govern follicular growth and atresia, with a special focus on their regulation by granulosa cells. First, ovarian folliculogenesis in adult life is outlined. Then, we explain about the regulation of follicular growth and atresia by granulosa cells, in which hormones, growth factors and cytokines, death ligand-receptor system and B cell lymphoma/leukemia 2 (BCL2) family members (mitochondriamediated apoptosis) are further discussed. © 2012 by the Society for Reproduction and Development. Source

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

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

Sekizaki T.,Tokyo University of Science
Journal of Disaster Research | Year: 2012

Streptococcus suis infections in pigs are often seen in major hog-producing countries. This bacterium is also a zoonotic agent affecting, for the most part, people in close contact with swine or pork by-products. The human S. suis infections have generally been sporadic; however, in recent years, this bacterium has strongly emerged as an important public health issue in Southeast and East Asia. Most human infections have so far been recognized to cause adult meningitis; however, a recent outbreak that occurred in Sichuan Province, China, involved a fatal disease, known as the streptococcus toxic-shock syndrome. Almost all human infections were caused by contact with diseased pigs or contaminated pork by-products, so reducing the number of virulent strains of S. suis in hog populations is an important task in diminishing the level of risk in human S. suis infections. However, the S. suis strains show various degrees of virulence, and many clinically healthy pigs may carry S. suis, some of which are avirulent and some of whichmust be virulent. Therefore, a rapid assay system to identify the virulent strains of S. suis is urgently needed. Here, general information on S. suis is described, and the recent research progress on this bacterium is summarized. Source

Shimizu M.,Tokyo University of Science
Bioscience, Biotechnology and Biochemistry | Year: 2010

The small intestine is an organ responsible for nutrient absorption, barrier functions, signal recognition/transduction, and the production of bioactive compounds. These functions are known to be regulated by such factors as hormones and cytokines, but substances contained in the daily diet are also thought to play roles as major modulators of intestinal functions. Intestinal epithelial cells (IECs), which form a monolayer covering the inside surface of the intestinal tract, are particularly important in this modulation, because they directly interact with intestinal contents, including food substances, their digests, and gut microbial components. Using cell-based in vitro assays, we investigated the food-IEC interactions at the cellular and molecular levels, and found that a variety of food substances affected the transporter activity, tight junction permeability, metabolic enzyme expression, immune functions, and so on. Modulation of the intestinal functions by dietary substances is therefore essential to promote health. Source

Takigawa R.,University of Tokyo | Higurashi E.,Tokyo University of Science | Suga T.,University of Tokyo | Kawanishi T.,Tokyo Institute of Technology
IEEE Journal on Selected Topics in Quantum Electronics | Year: 2011

In this study, passive alignment and mounting of lithium niobate (LiNbO3) chips, with a large mismatch in the coefficient of thermal expansion with most semiconductors, are demonstrated for hybrid-integrated optical devices. LiNbO3 chips were aligned passively using the visual index alignment method and were subsequently bonded on the Si substrates by low-temperature solid-state bonding with Au microbumps, which allow for electrical connections and heat dissipation. Au-Au bonding was carried out at 100 °C in ambient air after surface activation by argon RF plasma. The vertical bonding accuracy was determined by assessing the height variations of the Au microbumps due to the plastic deformation in the bonding process. The bonding accuracies in the horizontal and vertical directions were estimated to be within ±1 μm. Average excess loss due to misalignment between titanium-diffused single-mode LiNbO3 waveguides and V-groove-guided single-mode fibers was about 0.5-dBm per interface (wavelength: 1.55 μm). © 2006 IEEE. Source

Otsuka H.,Tokyo University of Science
Molecules | Year: 2010

Surface engineering techniques for cellular micropatterning are emerging as important tools to clarify the effects of the microenvironment on cellular behavior, as cells usually integrate and respond the microscale environment, such as chemical and mechanical properties of the surrounding fluid and extracellular matrix, soluble protein factors, small signal molecules, and contacts with neighboring cells. Furthermore, recent progress in cellular micropatterning has contributed to the development of cell-based biosensors for the functional characterization and detection of drugs, pathogens, toxicants, and odorants. In this regards, the ability to control shape and spreading of attached cells and cell-cell contacts through the form and dimension of the cell-adhesive patches with high precision is important. Commitment of stem cells to different specific lineages depends strongly on cell shape, implying that controlled microenvironments through engineered surfaces may not only be a valuable approach towards fundamental cell-biological studies, but also of great importance for the design of cell culture substrates for tissue engineering. To develop this kind of cellular microarray composed of a cell-resistant surface and cell attachment region, micropatterning a protein-repellent surface is important because cellular adhesion and proliferation are regulated by protein adsorption. The focus of this review is on the surface engineering aspects of biologically motivated micropatterning of two-dimensional surfaces with the aim to provide an introductory overview described in the literature. In particular, the importance of non-fouling surface chemistries is discussed. © 2010 by the authors. Source

Fujita M.,University of Tokyo | Fujita T.,Tokyo University of Science
Current Hypertension Reports | Year: 2013

The role of sympathetic nerve activity in hypertension is currently receiving increased attention, because catheter-based renal denervation was recently shown to reduce blood pressure safely in patients with treatment-resistant hypertension. The central nervous system, which regulates sympathetic nerve activity and blood pressure, is pivotal. Central sympathoexcitation has been shown to be deeply involved in the pathogenesis of salt-sensitive hypertension, although its precise mechanisms have not yet been fully elucidated due to their complexity. Recently, a role for brain oxidative stress in sympathoexcitation has been suggested in some hypertensive animal models. We have demonstrated that increased brain oxidative stress may elevate arterial pressure through central sympathoexcitation in salt-sensitive hypertension. Several factors other than oxidative stress have also been shown to play important roles in central sympathetic activation. In the future, strategies may be developed to elicit a sympathetic inhibition by modulating these factors to prevent and manage salt-sensitive hypertension. © 2013 Springer Science+Business Media New York. Source

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

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

Ganguly M.,Indian Institute of Technology Kharagpur | Pal A.,Indian Institute of Technology Kharagpur | Negishi Y.,Tokyo University of Science | Pal T.,Indian Institute of Technology Kharagpur
Langmuir | Year: 2013

Evolution of fluorescence from a giant core-shell particle is new and synergistic, which requires both gold and silver ions in an appropriate ratio in glutathione (GSH) solution. The formation of highly fluorescent Ag 2/Ag3 clusters on the surface of AuI assembly results in giant AuI core-Ag0 shell water-soluble microparticles (∼500 nm). Here, AuI acts as the template for the generation of fluorescent Ag clusters. The presence of gold under the synthetic strategy is selective, and no other metal supports such synergistic evolution. The core-shell particle exhibits stable and static emission (emission maximum, 565 nm; quantum yield, 4.6%; and stroke shift, 179 nm) with an average lifetime of ∼25 ns. The drift of electron density by the AuI core presumably enhances the fluorescence. The positively charged core offers unprecedented long-term stability to the microparticles in aqueous GSH solution. © 2013 American Chemical Society. Source

Asahi Y.,Tokyo University of Science
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

Ubiquitous means being present everywhere at the same time, which expresses the situation that users can have no trouble accessing computers and networks from anywhere, anytime. This broadens its prospect in marketing. On top of the customer information and buying history that the company keeps track of, the customers' environment information including time, place and activity field has become available. These days, due to ubiquitous marketing, concierge-styled service becomes a real possibility. This is where various suggestions are provided according to users' interests, thoughts and behavioral patterns. This research explains consumer awareness based on a questionnaire survey about consumers' privacy in ubiquitous marketing. © 2011 Springer-Verlag. Source

Osaka N.,Tokyo University of Agriculture and Technology | Shibayama M.,Tokyo University of Science
Macromolecules | Year: 2012

A study was conducted to investigate pressure effects on cononsolvency behavior of poly(nisopropylacrylamide) (PNIPA) in water/DMSO mixed solvents. The polymer was dissolved in a mixture of hydrogenated water and DMSO, in which the mole fraction of DMSO was varied. The solutions of PNIPA in water/DMSO were transparent at low temperature with low mole fraction of DMSO at ambient pressure. The transmission rapidly decreased at the lower critical solution temperature by heating. The P-T phase diagram of PNIPA in water/DMSO was obtained by in situ transmission measurement under LCST conditions and UCST conditions. Addition of DMSO into the solutions reduced the total number of hydrogen bonding along the chain because of the competitive attachment and detachment of the two solvents. Source

Oka T.,Keio University | Onodera Y.,Keio University | Nagai M.,High Energy Accelerator Research Organization | Tanaka K.,Keio University | And 3 more authors.
Astrophysical Journal, Supplement Series | Year: 2012

We present high-resolution CO J = 3-2 maps of the Galactic center region, taken with the ASTE 10m telescope. We have collected approximately 30,000 spectra with a 34″ grid spacing. The mapping area is roughly -1°.8 < l < +35 and -08 < b < +0°.9, which includes the central molecular zone and Bania's Clump 2, covering almost the full extent of the molecular gas concentration in the Galactic center. These CO J = 3-2 images show a behavior similar to the CO J = 1-0 images with the same resolution. Molecular gas in the Galactic center shows a higher J = 3-2/J = 1-0 intensity ratio (0.7) than the gas in the spiral arms in the Galactic disk (∼0.4). The CO J = 3-2/CO J = 1-0 luminosity ratio is 0.71. We see several regions with very high J = 3-2/J = 1-0 intensity ratios exceeding 1.5, including the Sgr A, l = +13, l = -04, and l = -1°.2 regions. A number of small spots of high ratio gas are also found. Many of them have large velocity widths, indicating that they are spots of hot molecular gas shocked by unidentified supernovae and/or winds from massive stars. © 2012. The American Astronomical Society. All rights reserved. Source

Yamada S.,Tokyo University of Science
Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B | Year: 2011

The objective of the present paper is to perform the effective control by the periodic disturbance in a backward facing step in low Reynolds number range. At first, in order to clarify the overall characteristics of separating shear layer, the flow behavior of the transverse vortices in the main flow and a reattachment length on a lower side wall were investigated by Hot-wire anemometer and Micro Flow Sensor(MFS). The characteristic frequency of the flow fluctuation was estimated to be about 36 Hz from FFT analysis. The change of the upstream vortex structure affects the downstream periodic flow behavior. To identify the periodic flow, the frequency dominating the separating shear layer was analyzed by the linear stability theory. From this result, the periodic disturbance was given to separating flow by means of the synthetic jets from the upper wall. The effective forcing frequency of the synthetic jets was evaluated from the reattachment length on the lower wall and the flow behavior in the separating shear layer. © 2011 The Japan Society of Mechanical Engineers. Source

Kokubun J.,Tokyo University of Science | Dmitrienko V.E.,RAS Shubnikov Institute of Crystallography
European Physical Journal: Special Topics | Year: 2012

Experimental results and their theoretical explanation are reviewed for fundamentals of anisotropic resonant X-ray scattering. Resonant scattering depends on X-ray polarization, i. e. the scattering reflects anisotropic environment of atoms in crystal. The polarization anisotropy in atomic scattering can excite the forbidden Bragg reflections. Studying this type of forbidden reflections we can distinguish electronic orbitals of specific symmetry. This method is very useful for studying local electronic states in crystal. We reveal detailed property of the anisotropic scattering, effect of quadrupole transition, thermal motion, magnetic scattering and so on. Especially successful examples are given in detail: observation of phase of the scattering factor, the hybridization of states with different parity, local chirality of atom in centrosymmetric crystals, thermal-motion-induced resonant reflections, etc. © 2012 EDP Sciences, Springer-Verlag. Source

Yamamoto M.,Tokyo University of Science
Journal of Thermal Science | Year: 2013

Nowadays Computational Fluid Dynamics (CFD) software is adopted as a design and analysis tool in a great number of engineering fields. We can say that single-physics CFD has been sufficiently matured in the practical point of view. The main target of existing CFD software is single-phase flows such as water and air. However, many multi-physics problems exist in engineering. Most of them consist of flow and other physics, and the interactions between different physics are very important. Obviously, multi-physics phenomena are critical in developing machines and processes. A multi-physics phenomenon seems to be very complex, and it is so difficult to be predicted by adding other physics to flow phenomenon. Therefore, multi-physics CFD techniques are still under research and development. This would be caused from the facts that processing speed of current computers is not fast enough for conducting a multi-physics simulation, and furthermore physical models except for flow physics have not been suitably established. Therefore, in near future, we have to develop various physical models and efficient CFD techniques, in order to success multi-physics simulations in engineering. In the present paper, I will describe the present states of multi-physics CFD simulations, and then show some numerical results such as ice accretion and electro-chemical machining process of a three-dimensional compressor blade which were obtained in my laboratory. Multi-physics CFD simulations would be a key technology in near future. © 2013 Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag Berlin Heidelberg. Source

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

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

Kitagawa Y.,University of Tokyo | Segawa H.,Tokyo University of Science | Ishii K.,University of Tokyo
Angewandte Chemie - International Edition | Year: 2011

Direction decides: Magneto-chiral dichroism describes the dependence of the absorbance of a chiral molecule on the direction of a magnetic field to which it is exposed, and it may help to explain the homochirality of life. This phenomenon was now observed in organic compounds using porphyrin J-aggregates. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Fujita T.,Tokyo University of Science | Fujita T.,Japan Science and Technology Agency
Journal of the American Society of Nephrology | Year: 2014

A central role for the kidney among the systems contributing to BP regulation and the development of hypertension has been proposed. Both the aldosterone/mineralocorticoid receptor pathway and the renal sympathetic nervous system have important roles in the regulation of renal excretory function and BP control, but the mechanisms underlying these processes have remained unclear. However, recent studies revealed the activation of two pathways in salt-sensitive hypertension. Notably, Rac1, a member of the Rho-family of small GTP binding proteins, was identified as a novel ligand-independent modulator of mineralocorticoid receptor activity. Furthermore, these studies point to crucial roles for the Rac1-mineralocorticoid receptor-NCC/ENaC and the renal b-adrenergic stimulant-glucocorticoid receptor-WNK4-NCC pathways in certain rodent models of salt-sensitive hypertension. The nuclearmineralocorticoid and glucocorticoid receptorsmay contribute to impaired renal excretory function and the resulting salt-sensitive hypertension by increasing sodium reabsorption at different tubular segments. This review provides an indepth discussion of the evidence supporting these conclusions and considers the significance with regard to treating salt-sensitive hypertension and salt-induced cardiorenal injury. Copyright © 2014 by the American Society of Nephrology. Source

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

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

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

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

Gan X.,Yale University | Wang J.,Yale University | Wang C.,Yale University | Sommer E.,University of Dundee | And 7 more authors.
Nature Cell Biology | Year: 2012

Mammalian target of rapamycin complex 2 (mTORC2) phosphorylates AGC protein kinases including protein kinase C (PKC) and regulates cellular functions such as cell migration. However, its regulation remains poorly understood. Here we show that lysophosphatidic acid (LPA) induces two phases of PKC-δ hydrophobic motif phosphorylation. The late phase is mediated by Gα 12, which specifically activates ARAF, leading to upregulation of the RFFL E3 ubiquitin ligase and subsequent ubiquitylation and degradation of the PRR5L subunit of mTORC2. Destabilization of PRR5L, a suppressor of mTORC2-mediated hydrophobic motif phosphorylation of PKC-δ, but not AKT, results in PKC-δ hydrophobic motif phosphorylation and activation. This Gα 12-mediated signalling pathway for mTORC2 regulation is critically important for fibroblast migration and pulmonary fibrosis development. © 2012 Macmillan Publishers Limited. All rights reserved. Source

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

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

Inazu M.,Tokyo University of Science
Biopharmaceutics and Drug Disposition | Year: 2014

Choline is essential for the synthesis of the major membrane phospholipid phosphatidylcholine (PC), the methyl donor betaine and the neurotransmitter acetylcholine (ACh). Elevated levels of choline and up-regulated choline kinase activity have been detected in various cancers. Thus, the intracellular accumulation of choline through choline transporters is the rate-limiting step in phospholipid metabolism and a prerequisite for cancer cell proliferation. Previous studies have demonstrated abnormalities in choline uptake and choline phospholipid metabolism in cancer cells using the imaging of cancer with positron emission tomography (PET) and magnetic resonance spectroscopy (MRS). The aberrant choline metabolism in cancer cells is strongly correlated with their malignant progression. Using quantitative real-time PCR, the mRNA expression of choline transporters was measured, and it was found that choline transporter-like proteins CTLs/SLC44 family are highly expressed in various cancer cell lines. Choline uptake through CTLs is associated with cell viability, and the functional inhibition of CTLs could promote apoptotic cell death. Furthermore, nonneuronal cholinergic systems that include CTLs-mediated choline transport are associated with cell proliferation and their inhibition promotes apoptotic cell death in colon cancer, small cell lung cancer and human leukemic T-cells. The identification of this new CTLs-mediated choline transport system provides a potential new target for cancer therapy. Copyright © 2014 John Wiley &Sons, Ltd. Source

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

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

Dao V.H.,Catholic University of Leuven | Dao V.H.,University of Bordeaux 1 | Chibotaru L.F.,Catholic University of Leuven | Nishio T.,Catholic University of Leuven | And 2 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

We predict that in a bulk type-1.5 superconductor, the competing magnetic responses of the two components of the order parameter can result in group-stabilized giant vortices and individual rings of vortices in the absence of any extrinsic pinning or confinement mechanism. We also determine within the Ginzburg-Landau theory a condition for the robustness of type 1.5 in the vicinity of the critical temperature, and we find a rich phase diagram with successions of behaviors such as type 1→ type 1.5→ type 2→ type 1.5 when temperature decreases. © 2011 American Physical Society. Source

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

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

Tadashi N.,Tokyo University of Science
Chemical Record | Year: 2010

Since the isolation of brevetoxin-B, a red tide toxin, many bioactive marine natural products featuring synthetically challenging trans-fused polycyclic ether ring systems have been reported. We have developed SmI2-induced cyclization of β-alkoxyacrylate with aldehyde, affording 2,6-syn-2,3-trans-tetrahydropyran (THP) or 2,7-syn-2,3-trans-oxepane with complete stereoselection, as a key reaction of efficient iterative and bi-directional strategies for the construction of these polycyclic ethers. This reaction is also applicable to the synthesis of 3-, 5-, and 6-methyl-THPs and 3,5-dimethyl-THP. The synthesis of 2-methyl- and 2,6-dimethyl-THPs was accomplished by means of a unique methyl insertion. Recently, the SmI2-induced cyclization was extended to similar reactions using β-alkoxyvinyl sulfone and sulfoxide. Reaction of (E)- and (Z)-β-alkoxyvinyl sulfone-aldehyde afforded 2,6-syn-2,3-trans- and 2,6-syn-2,3-cis- THPs, respectively. Reaction of (E)-β-alkoxyvinyl (R)-and (S)-sulfoxides gave 2,6-anti-2,3-cis- and 2,6-syn-2,3-trans-THPs, respectively. Reaction of (Z)-β-alkoxyvinyl (R)-sulfoxides gave 2,6-syn-2,3-cis-THP and an olefinic product, while that of (Z)-β-alkoxyvinyl (S)-sulfoxide afforded a mixture of many products. These SmI2-induced cyclizations have been applied to the total syntheses of various natural products, including brevetoxin-B, mucocin, pyranicin, and pyragonicin. Synthetic studies on gambierol and maitotoxin are also introduced. © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Source

Doi R.,Tokyo University of Science
Optical Engineering | Year: 2013

For optimal management of agricultural fields by remote sensing, discrimination of the crop canopy from weeds and other objects is essential. In a digital photograph, a rice canopy was discriminated from a variety of weed and tree canopies and other objects by overlapping binary image layers of red-green-blue and other color components indicating the pixels with target canopy-specific (intensity) values based on the ranges of means ±3(×) standard deviations. By overlapping and merging the binary image layers, the target canopy specificity improved to 0.0015 from 0.027 for the yellow 1× standard deviation binary image layer, which was the best among all combinations of color components and means ±(3×) standard deviations. The most target rice canopy- likely pixels were further identified by limiting the pixels at different luminosity values. The discriminatory power was also visually demonstrated in this manner. © 2013 Society of Photo- Optical Instrumentation Engineers (SPIE). Source

Usuki T.,Tokyo University of Science
Journal of Sound and Vibration | Year: 2013

The aim is to extend the theory to a viscoelastic beam that satisfies stress-free surface boundary conditions. A viscoelastic material (polyvinyl chloride) was used in the numerical calculation, and the phase and group velocity curves were derived for a viscoelastic beam from the case without damping to the case with damping proportional to the first-order derivative with respect to time. Based on the preliminary data, the phase and group velocity curves were derived for a beam of solid circular cross section. As a result, it was confirmed that, as earlier pointed out for elastic materials, these curves were controlled by the phase velocity inherent to the material. Finally, with the phase velocity and the group velocity of the beam, regularities were derived for the absolute value of the complex velocity on the complex plane. © 2012 Elsevier Ltd. All rights reserved. Source

Matsunaga S.,Tokyo University of Science
Cytologia | Year: 2016

Fluorescent in situ hybridization (FISH) has been a powerful technique to reveal chromosomal loci and distribution of DNA sequences in metaphase chromosomes. Three-dimensional FISH (3D-FISH) has also revealed the chromosome territory of interphase chromosomes in the nucleus. Recently, 3D-FISH has played a supportive or complementary role to confirm the genome organization and topologically associated domains, which are provided by chromosome conformation capture techniques. © 2016 The Japan Mendel Society. Source

Xu Y.,University of Miyazaki | Komiyama M.,Tokyo University of Science
Methods | Year: 2012

Human telomeres play an important role in critical processes underlying genome stability, cancer, and aging. For a long time, telomeres have been considered transcriptionally silent. A recent finding demonstrated that telomere DNA is transcribed into telomeric repeat-containing RNA (referred to as TERRA) in mammalian cells. The existence of TERRA RNA may reveal a new level of regulation and protection of chromosome ends that could promote valuable insight into fundamental biological processes such as cancer and aging. Revealing the structure and function of telomere RNA will be essential for understanding telomere biology and telomere-related diseases. NMR and X-ray crystallography have demonstrated that human telomere RNA forms G-quadruplex structures. More recently, human telomere RNA is suggested to form a G-quadruplex dimer in the living cells by employing a light-switching probe. The proposed structures may be a valuable target for anticancer agents directed against telomeres.This review highlights the structures and topologies for telomere RNA G-quadruplex and recent efforts in the design of telomere RNA G-quadruplex ligands. The future challenges in the field are outlined. © 2012 Elsevier Inc. Source

Sasa S.-I.,Tokyo University of Science
Journal of Physics A: Mathematical and Theoretical | Year: 2010

A two-dimensional lattice gas model is proposed. The ground state of this model with a fixed density is neither periodic nor quasi-periodic. It also depends on the system size in an irregular manner. On the other hand, it is ordered in the sense that the entropy density is zero in the thermodynamic limit. The existence of a thermodynamic transition associated with such irregularly ordered ground states is conjectured from a duality relation for a thermodynamic function. This conjecture is supported by a phenomenological argument and numerical experiments. © 2010 IOP Publishing Ltd. Source

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

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

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

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

Kim K.H.,Fritz Haber Institute | Watanabe K.,Fritz Haber Institute | Watanabe K.,Tokyo University of Science | Mulugeta D.,Fritz Haber Institute | And 2 more authors.
Physical Review Letters | Year: 2011

Strong fluence dependence of photodesorption cross sections is observed in femtosecond laser photodesorption of NO from (NO)2 on silver nanoparticles, in contrast to femtosecond photodesorption on bulk metals. The time scale of excitation buildup is found to be equal or less than the pulse duration of ∼100fs; NO translational energies are independent of fluence and pulse duration. We propose a nanoparticle-specific nonlinear mechanism in which, due to confinement, strongly nonthermal hot-electron distributions are maintained during the femtosecond pulses, enhancing the normal desorption pathway. © 2011 American Physical Society. Source

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

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

Terasaka N.,University of Tokyo | Hayashi G.,University of Tokyo | Hayashi G.,Tokyo University of Science | Katoh T.,University of Tokyo | And 2 more authors.
Nature Chemical Biology | Year: 2014

The Watson-Crick base pairs between the 3 €2-terminal end of tRNAs and ribosomal RNA in the peptidyl transferase center are universally conserved. Here, we report that the introduction of compensatory mutations to Escherichia coli RNAs in this site leads to an orthogonal system independent of the wild-type counterpart, as demonstrated via the production of two peptide sequences from a single mRNA. This work thus identifies a new way to reprogram the genetic code. © 2014 Nature America, Inc. Source

Kamiura M.,Tokyo University of Science
AIP Conference Proceedings | Year: 2010

Abduction, which is articulated by C.S. Peirce, is one of the forms of inference. Abduction has been researched not only in philosophy but also in artificial intelligence and information science. Finlay and Dix's representation of abduction (1996) has almost the same meaning which is given by Peirce. On the other hand, Sawa and Gunji (2010) express three types of inference as operations of arrows on a simple triangular diagram. In the present paper, we show that Sawa-Gunji's representation of abduction is consistent with Finlay-Dix's one, and synthesize the two representations. Both parameter estimation and abduction occupy a similar position on the synthesized representation, but they are not completely corresponding. We present "incomplete" parameter estimation as a sort of "simulated abduction", since abduction has an intrinsic incompleteness, which means that abduction is formally equivalent to "the logical fallacy affirming the consequent". In other words, a numerical aspect of abduction (i.e. the simulated abduction) is formalized as incomplete parameter estimation. The concept of simulated abduction is applied to parameter estimation of auto-regressive models, and the effects of it is investigated. As a result of the numerical analyses, the distribution of the incompletely estimated parameter shows a power law of the slop -2 in the tail, although conventionally estimated parameter is normally distributed. The power law of the incompletely estimated parameter is based on the structure of ratio distribution. In other words, this result shows that the power law can arise when system observers premise a linearity of input and output data which are too small to estimate the system structure. We call the premise of the system observers "linearity bias". As an example of the cause of power law distributions, self-organized criticality (SOC) has been known. These distributions are based on the mechanisms of the systems themselves, which have some organized interaction between their elements. On the other hand, power law distribution which is derived from the incomplete parameter estimation and the linearity bias is not based on a mechanism of system itself but on relationship between data on the system and observer of the data. Consequently, our research suggests that complexity expressed by a power law distribution can be derived from the incomplete parameter estimation which is a numerical aspect of abduction and is different from SOC mechanisms. © 2010 American Institute of Physics. Source

Minezaki T.,University of Tokyo | Matsushita K.,Tokyo University of Science
Astrophysical Journal | Year: 2015

We propose a new method for estimating the mass of a supermassive black hole, applicable to obscured active galactic nuclei (AGNs). This method estimates the black hole mass using the width of the narrow core of the neutral FeKα emission line in X-rays and the distance of its emitting region from the black hole based on the isotropic luminosity indicator via the luminosity scaling relation. Assuming the virial relation between the locations and the velocity widths of the neutral FeK α line core and the broad Hβ emission line, the luminosity scaling relation of the neutral FeKα line core emitting region is estimated. We find that the velocity width of the neutral FeKα line core falls between that of the broad Balmer emission lines and the corresponding value at the dust reverberation radius for most of the target AGNs. The black hole mass MBH,FeKα estimated with this method is then compared with other black hole mass estimates, such as the broad emission-line reverberation mass MBH,rev for type 1 AGNs, the mass MBH,H2O based on the H2O maser, and the single-epoch mass estimate MBH,pol based on the polarized broad Balmer lines for type 2 AGNs. We find that MBH,FeKα is consistent with MBH,rev and MBH,pol, and find that MBH,FeKα correlates well with MBH,H2O. These results suggest that MBH,FeKα is a potential indicator of the black hole mass for obscured AGNs. In contrast, MBH,FeKα is systematically larger than MBH,H2O by about a factor of 5, and the possible origins are discussed. © 2015. The American Astronomical Society. All rights reserved. Source

Nagasawa H.,Tokyo University of Science
Bioscience, Biotechnology and Biochemistry | Year: 2013

Biomineralization is a process of mineral deposition by organisms. Calcium salts are the major component of various biominerals, calcium carbonate being the predominant type in aquatic organisms. The mechanism of biomineralization has been conventionally analyzed by microscopic observation. The findings obtained suggest that minute amounts of organic matrices in biominerals play a key role in biomineralization. We first introduced the methodology of bioactive compound chemistry into this research field. Using various biominerals, such as the exoskeleton and gastroliths of the crayfish, the otoliths and scales of fish, the coccoliths of coccolithophores, bivalve shells, and coral skeleton, a range of organic matrices were purified by simple functional assays, and their chemical structures were determined. The function of each matrix component was estimated by its ability to interact with calcium carbonate and by in vitro crystallization, immunological localization, and site-specific and temporal expression of the encoding genes in the case of proteins and peptides, among other compounds. It was found that there was almost no similarity in chemical structure among organic matrices from various biominerals, but similarity in function was observed, and that made possible the functional classification of organic matrices. Source

Sugitani T.,Osaka University | Hamasaki T.,Osaka University | Hamada C.,Tokyo University of Science
Biometrical Journal | Year: 2013

In this paper, we propose a partition testing for adaptive clinical trials with structured study objectives. The proposed approach is a combination of the graphical approach with partition testing. The proposed approach enables one to handle many types of structured objectives, to tailor a multiple test procedure to given structured objectives, and to draw sensible conclusions in adaptive clinical trials. In addition, the proposed approach reduces to the Bonferroni-based graphical approaches that can allow adaptations such as treatment selection and sample size reassessment during the course of the trial. Some practical aspects of the proposed approach are investigated via a simulation study. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Matsumoto A.,Tokyo University of Science
Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry | Year: 2015

Thanks to the development of automation systems and programs for single crystal X-ray diffraction analysis, X-ray structure analysis have become a familiar technic for organic chemists to obtain structural information. However, determination of the absolute configuration of organic compounds only including light-atom (C, H, N, O) by X-ray diffraction have been a difficult topic due to the weak resonant scattering from light atoms. The main purpose of this review is to introduce recent developments of absolute structure determination method by X-ray structure analysis. New algorisms, such as Hooft parameter and Parsons parameter, make it possible to determine the absolute configuration of organic compound by typical X-ray diffractometer without any special equipment. Source

Kitamura N.,Tokyo University of Science
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan | Year: 2015

Since a high ionic conduction in a crystal can be achieved by tailoring point defects generally, an investigation on a defect structure is of much importance in the field of the solid-state electrochemistry. Due to a non-periodic nature of a defect distribution, however, a typical atomic-configuration analysis with the Bragg reflections is insufficient to gain deep understanding on defects in a crystal. In order to get a clear snapshot of an atomic configuration of a crystal with defects, this paper pays special attention on advanced analytical methods using the pair distribution function (PDF) combined with theoretical calculations. The PDF analyses on some ion-conducting oxides succeed in revealing mobile-ion trappings by specific cations. Especially, the reverse Monte Carlo modeling with both the Bragg reflections and convolved structure factors S(Q) enables us to discuss an intermediate-range atomic configuration with a couple of hundreds of atoms, and then visualize mobile-ion distribution in a crystal as a snapshot. An electronic structure computed by the density functional theory can explain well the trapping mechanism of the mobile ions. Such a strategy will shed new light on the defect chemistry and give a breakthrough for discovering a novel ion-conducting crystal. © 2015 The Ceramic Society of Japan. All rights reserved. Source

Usuki T.,Tokyo University of Science
Journal of Sound and Vibration | Year: 2013

The moduli of conventional elastic structural materials are extended to one of the viscoelastic materials through a modification whereby the dynamic moduli converge to the static moduli of elasticity as the fractional order approaches zero. By plotting phase velocity curves and group velocity curves of plane waves and Rayleigh surface wave for a viscoelastic material (polyvinyl chloride foam), the influence of the fractional order of viscoelasticity is examined. The phase and group velocity curves in the high frequency range were derived for longitudinal, transverse, and Rayleigh waves inherent to the viscoelastic material. In addition, the equation for the phase velocity was mathematically derived on the complex plane, too, and graphically illustrated. A phenomenon was found that, at the moment when the fractional order of the time derivative reaches an integer value 1, the curve on the complex plane becomes completely different, exhibiting snap-through behavior. We examined the mechanism of the snap-through mathematically. Numerical calculation examples were solved, and good agreement was confirmed between the numerical calculation and the analytical expression mentioned above. From the results of the numerical example, regularities were derived for the absolute value of the complex phase and group velocities on the complex plane. © 2013 Elsevier Ltd. All rights reserved. Source

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

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

Ishimaru Y.,Tokyo University of Science
Bioscience, Biotechnology and Biochemistry | Year: 2015

Taste enables organisms to determine the properties of ingested substances by conveying information regarding the five basic taste modalities: sweet, salty, sour, bitter, and umami. The sweet, salty, and umami taste modalities convey the carbohydrate, electrolyte, and glutamate content of food, indicating its desirability and stimulating appetitive responses. The sour and bitter modalities convey the acidity of food and the presence of potential toxins, respectively, stimulating aversive responses to such tastes. In recent years, the receptors mediating sweet, bitter, and umami tastes have been identi fied as members of the T1R and T2R G-protein-coupled receptor families; however, the molecular mechanisms underlying sour taste detection have yet to be clearly elucidated. This review covers the molecular mechanisms proposed to mediate the detection and transmission of sour stimuli, focusing on polycystic kidney disease 1-like 3 (Pkd1l3), Pkd2l1, and carbonic anhydrase 4 (Car4). © 2014 Japan Society for Bioscience, Biotechnology, and Agrochemistry. Source

Watanabe N.,Tokyo University of Science
Russian Journal of Mathematical Physics | Year: 2014

In classical information theory, one of the most important theorems are the coding theorems, which were discussed by calculating the mean entropy and the mean mutual entropy defined by the classical dynamical entropy (Kolmogorov-Sinai). The quantum dynamical entropy was first studied by Emch [13] and Connes-Stormer [11]. After that, several approaches for introducing the quantum dynamical entropy are done [10, 3, 8, 39, 15, 44, 9, 27, 28, 2, 19, 45]. The efficiency of information transmission for the quantum processes is investigated by using the von Neumann entropy [22] and the Ohya mutual entropy [24]. These entropies were extended to S- mixing entropy by Ohya [26, 27] in general quantum systems. The mean entropy and the mean mutual entropy for the quantum dynamical systems were introduced based on the S- mixing entropy. In this paper, we discuss the efficiency of information transmission to calculate the mean mutual entropy with respect to the modulated initial states and the connected channel for the quantum dynamical systems. © 2014, Pleiades Publishing, Ltd. Source

Zawidzki M.,Tokyo University of Science
International Journal of Design and Nature and Ecodynamics | Year: 2013

This paper introduces the concept of an innovative truss system (truss-Z) that allows the creation of complex and re-configurable structural networks with certain organic aesthetics. The system is composed of two modular units used for constructing the main structure of the truss and a single module for the supporting structure. An example is given of the use of the system to provide pedestrian walkways, which allows the connection of any given number of points in space (terminals). It also permits the creation of loops and multiple branches of the structure. The geometry of the truss-Z is based on a universal module which, subject to geometrical transformations, allows the construction of structural links along virtually any 3D paths. Scale models of the modules are created from resin cast using two types of mold and timber using an aluminum template. Various algorithms for local and global discrete optimization of the modular structure are proposed. A number of cases of creating a truss network in a constrained environment are discussed. The elements of the environment model real obstacles such as roads, buildings, and watercourses that may constrain both the run of the truss and the placement of the supports. An example of a truss-Z network connecting six terminals in an environment with three obstacles is shown. The issues of fabrication of the modules of the truss, full-size manufacturing, and joinery are also discussed. © 2013 WIT Press. Source

Tanaka S.,Hiroshima University | Okada H.,Tokyo University of Science | Okazawa S.,Hiroshima University | Fujikubo M.,Osaka University
International Journal for Numerical Methods in Engineering | Year: 2013

This paper presents fracture mechanics analysis using the wavelet Galerkin method and extended finite element method. The wavelet Galerkin method is a new methodology to solve partial differential equations where scaling/wavelet functions are used as basis functions. In solid/structural analyses, the analysis domain is divided into equally spaced structured cells and scaling functions are periodically placed throughout the domain. To improve accuracy, wavelet functions are superposed on the scaling functions within a region having a high stress concentration, such as near a hole or notch. Thus, the method can be considered a refinement technique in fixed-grid approaches. However, because the basis functions are assumed to be continuous in applications of the wavelet Galerkin method, there are difficulties in treating displacement discontinuities across the crack surface. In the present research, we introduce enrichment functions in the wavelet Galerkin formulation to take into account the discontinuous displacements and high stress concentration around the crack tip by applying the concept of the extended finite element method. This paper presents the mathematical formulation and numerical implementation of the proposed technique. As numerical examples, stress intensity factor evaluations and crack propagation analyses for two-dimensional cracks are presented. © 2012 John Wiley & Sons, Ltd. Source

Zuhdi U.,Tokyo University of Science | Zuhdi U.,Bandung Institute of Technology
Journal of Physics: Conference Series | Year: 2014

The purpose of this study is to get another perspective related to the role of Information and Communication Technology (ICT) sectors in national economy of Indonesia. The period of analysis of this study is 1990-2005. This study employs Input-Output (IO) analysis as a tool of analysis. More specifically, this study uses simple output multipliers method in order to achieve the purpose. Comparison with previous study is conducted in order to get the objective of this study. Previous study, using Structural Decomposition Analysis (SDA), showed that ICT sectors did not have an important role in Indonesian national economy in above period. The similar results also appear in this study. In other words, from this study, another perspective related to the role of these sectors in Indonesian national economy in analysis period is not found. Source

Dutta S.,Indian Institute of Technology Kharagpur | Ray C.,Indian Institute of Technology Kharagpur | Sarkar S.,Indian Institute of Technology Kharagpur | Pradhan M.,Indian Institute of Technology Kharagpur | And 2 more authors.
ACS Applied Materials and Interfaces | Year: 2013

Herein, a simple wet-chemical pathway has been demonstrated for the synthesis of silver nanoparticle conjugated reduced graphene oxide nanosheets where dimethylformamide (DMF) is judiciously employed as an efficient reducing agent. Altogether, DMF reduces both silver nitrate (AgNO3) and graphene oxide (GO) in the reaction mixture. Additionally, the presence of polyvinylpyrolidone (PVP) assists the nanophasic growth and homogeneous distribution of the plasmonic nanoparticle Ag(0). Reduction of graphene oxide and the presence of aggregated Ag NPs on reduced graphene oxide (rGO) nanosheets are confirmed from various spectroscopic techniques. Finally, the composite material has been exploited as an intriguing platform for surface enhanced Raman scattering (SERS) based selective detection of uranyl (UO2 2+) ion. The limit of detection has been achieved to be as low as 10 nM. Here the normal Raman spectral (NRS) band of uranyl acetate (UAc) at 838 cm-1 shifts to 714 and 730 cm-1 as SERS bands for pH 5.0 and 12.0, respectively. This distinguished Raman shift of the symmetric stretching mode for UO2 2+ ion is indicative of pronounced charge transfer (CT) effect. This CT effect even supports the higher sensitivity of the protocol toward UO2 2+ over other tested oxo-ions. It is anticipated that rGO nanosheets furnish a convenient compartment to favor the interaction between Ag NPs and UO2 2+ ion through proximity induced adsorption even at low concentration. © 2013 American Chemical Society. Source

Kamimura Y.,University of Tokyo | Edagawa K.,University of Tokyo | Takeuchi S.,Tokyo University of Science
Acta Materialia | Year: 2013

Peierls stresses (τ P) of dislocations of 66 slip systems in 52 crystals were estimated from experimental data either by direct extrapolation of the critical resolved shear stress (τ c) vs. temperature curve to absolute zero temperature, or from the T 0 value at which the temperature dependence of τ c vanishes, based on the kink-pair formation enthalpy, which is a function of τ P, described by the line tension model of the dislocation. The normalized τ P/G (G is the shear modulus) values are distributed over four orders of magnitude, but τ P/G values for a group of crystals with the same crystal structure are within an order of magnitude, indicating a homologous nature of τ P in crystals. In order to compare the results with the Peierls-Nabarro (P-N) formula generalized to any dislocation character, log(τ P/G) values were correlated with crystal parameters. In this generalized P-N plot, most of the plots deviate downwards from the Huntington relation (a revised, original P-N relation) and the results of the discretized P-N models of Ohsawa et al. (Ohsawa K, Koizumi H, Kirchner HOK, Suzuki T. Philos Mag A 1994;69:171), with the deviation becoming larger at large h/δ value, where h is the lattice spacing of the glide plane, and δ is the period of the lattice in the direction of the dislocation glide. In the plot, there is a tendency that the stronger the covalent character, the higher the τ P/G value, reflecting the general tendency of the normalized theoretical shear strength of crystals. © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Source

Seino H.,University of Tokyo | Hidai M.,Tokyo University of Science
Chemical Science | Year: 2011

Catalysis by the cubane-type Fe 4S 4 cluster has been found in metalloproteins such as biotin synthase, aconitase, and IspH, whereas some synthetic M 4S 4 clusters show catalytic activities for biologically related reactions or various types of organic transformations. This minireview summarizes recent progress in the chemistry of catalytic functions of cubane-type M 4S 4 clusters. © The Royal Society of Chemistry 2011. Source

Higurashi E.,Tokyo University of Science | Fukunaga T.,University of Tokyo | Suga T.,University of Tokyo
IEEE Journal of Quantum Electronics | Year: 2012

A low-temperature integration process for GaN-based heterogeneous devices was demonstrated by low-temperature bonding with Cr/Au thin films. Nonalloyed Cr/Au ohmic contacts on n-type GaN were obtained by surface treatment with low-energy fast atom beams of Ar for 15 s prior to metal deposition on n-type GaN. The as-deposited Cr/Au (50/250 nm) contacts showed a smooth surface with a root-mean-square roughness of 1.8 nm. Au-Au surface-activated bonding was carried out at 150°C in ambient air after surface activation by an Ar radio-frequency plasma. The GaN/Si samples bonded at a low temperature were so strong that bulk fracture was observed after the tensile test. © 2006 IEEE. Source

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

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

Tsujikawa S.,Tokyo University of Science
Progress of Theoretical and Experimental Physics | Year: 2014

In this paper, inflationary cosmology is reviewed, paying particular attention to its observational signatures associated with large-scale density perturbations generated from quantum fluctuations. In the most general scalar-tensor theories with second-order equations of motion, we derive the scalar spectral index ns, the tensor-to-scalar ratio r, and the nonlinear estimator fNL of primordial non-Gaussianities to confront models with observations of cosmic microwave background (CMB) temperature anisotropies. Our analysis includes models such as potential-driven slow-roll inflation, k-inflation, Starobinsky inflation, and Higgs inflation with non-minimal/derivative/Galileon couplings. We constrain a host of inflationary models by using the Planck data combined with other measurements to find models most favored observationally in the current literature. We also study anisotropic inflation based on a scalar coupling with a vector (or two-form) field and discuss its observational signatures appearing in the two-point and three-point correlation functions of scalar and tensor perturbations. Source

Kuroda R.,Tokyo University of Science
Quarterly Reviews of Biophysics | Year: 2015

Left-right (l-r) symmetry breaking and the establishment of asymmetric animal body plan during embryonic development are fundamental questions in nature. The molecular basis of l-r symmetry breaking of snails is a fascinating topic as it is determined by a maternal single handedness-determining locus at a very early developmental stage. This perspective describes the current state of the art of the chiromorphogenesis, mainly based on our own work, i.e. The first step of l-r symmetry breaking, as proven by our Mechanogenetics, before the start of zygotic gene expression, transfer of chirality information to the cell-fate determining stage, and the expression of nodal at the blastula stage. The Nodal signalling pathway is a common mechanism in vertebrates' chiromorphogenesis in later development. Studies on snails, especially Lymnaea (L.) stagnalis, shall give important insights into the molecular basis of chiromorphogenesis not only in Lophotrochozoa but in vertebrates as well. © 2015 Cambridge University Press. Source

Inagaki H.,University of Tokyo | Kiyokawa Y.,University of Tokyo | Tamogami S.,T. Hasegawa Co. | Watanabe H.,Tokyo University of Science | And 2 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Chemical communication plays an important role in the social lives of various mammalian species. Some of these chemicals are called pheromones. Rats release a specific odor into the air when stressed. This stress-related odor increases the anxiety levels of other rats; therefore, it is possible that the anxiety-causing molecules are present in the stress-related odorants. Here, we have tried to identify the responsible molecules by using the acoustic startle reflex as a bioassay system to detect anxiogenic activity. After successive fractionation of the stress-related odor, we detected 4-methylpentanal and hexanal in the final fraction that still possessed anxiogenic properties. Using synthetic molecules, we found that minute amounts of the binary mixture, but not either molecule separately, increased anxiety in rats. Furthermore, we determined that the mixture increased a specific type of anxiety and evoked anxiety-related behavioral responses in an experimental model that was different from the acoustic startle reflex. Analyses of neural mechanisms proposed that the neural circuit related to anxiety was only activated when the two molecules were simultaneously perceived by two olfactory systems. We concluded that the mixture is a pheromone that increases anxiety in rats. To our knowledge, this is the first study identifying a rat pheromone. Our results could aid further research on rat pheromones, which would enhance our understanding of chemical communication in mammals. © 2014, National Academy of Sciences. All rights reserved. Source

Mechanosensing and its downstream responses are speculated to involve sensory complexes containing Ca(2+)-permeable mechanosensitive channels. On recognizing hypo-osmotic stress, plant cells initiate activation of a widespread signal transduction network involving second messengers such as Ca(2+) to trigger inducible defense responses including the induction of transcriptional factors. However, most of the components involved in these signaling networks still remain to be identified. Recently we identified and investigated OsMCA1, the sole homolog of the MCA family putative Ca(2+)-permeable mechanosensitive channels in rice. Functional characterization of the OsMCA1-suppressed cells as well as the overexpressing cells indicated that OsMCA1 is involved in the regulation of plasma membrane Ca(2+) influx and NADPH oxidase-mediated generation of reactive oxygen species (ROS) induced by hypo-osmotic stress. Here we will discuss possible molecular mechanisms and physiological functions of the MCA protein in hypo-osmotic signaling. Source

Zheng R.,Tokyo University of Science
Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C | Year: 2013

Stability of a two-wheeled inverted pendulum vehicle was evaluated by using rider-vehicle modeling, electromyography of leg's muscle of rider, and subjective evaluation. A rider and the vehicle are synthetically modeled as a series-type double inverted pendulum. Utilizing auto-regressive exogenous (ARX) model method, correlative relations were found between control gains and stability of the vehicle that achieves better ride comfort. The experimental result shows that the higher the control gains, the smaller the activities of leg's muscles. However, according to subjective evaluation of ride comfort, higher gains did not always achieve better ride comfort. Moreover, the rider-vehicle model has no unstable poles, even when the vehicle model has an unstable pole. The poles of the rider-vehicle model had tendency to have bigger negative real numbers, which suggests stability of the vehicle can be evaluated by the positions of the poles of the rider-vehicle model. Through identification of the rider-vehicle model, the control gains of the rider's posture were calculated. It was found that the control gain against the rider's posture is dominant, and the higher the control gains of vehicle, the smaller the gain against the rider 's posture. The result shows stability of the vehicle can be evaluated by the control gains against the rider's posture. © 2013 The Japan Society of Mechanical Engineers. Source

Tohyama T.,Tokyo University of Science
Journal of Electron Spectroscopy and Related Phenomena | Year: 2015

Resonant inelastic X-ray scattering (RIXS) tuned for K and L edges of transition-metal element has recently contributed a lot to our understanding of electronic excitations in strongly correlated electron systems. We discuss a theoretical framework about K- and L-edge RIXS for cuprates and multi-orbital systems focusing on the relation to dynamical spin and charge structure factors. Present understanding of spin and charge dynamics in cuprates is also discussed based on very recent experimental and theoretical developments about electron-hole asymmetry. A small-momentum, low-energy charge mode is predicted as a challenging problem for future RIXS experiments. In multi-orbital systems, however, it is not easy to separate spin and charge components, since off-diagonal orbital contribution in dynamical response functions appears in RIXS with relatively strong intensity. ©2015 Elsevier B.V. All rights reserved. Source

Jia H.,University of Tokyo | Takahashi S.,Tokyo University of Science | Saito K.,University of Tokyo | Kato H.,University of Tokyo
Molecular Nutrition and Food Research | Year: 2013

This study addresses the effects of branched-chain amino acids (BCAA) on global gene expression in liver and skeletal muscle and the molecular mechanisms underlying the improvement in liver cirrhosis using DNA microarray analysis combined with RNase protection assay. Methods and results: Male Wistar rats administered carbon tetrachloride (CCl4) repeatedly for 19 weeks as a decompensated cirrhosis model were thereafter given BCAA-enriched diet (AL) or normal diet (LC) for 5 weeks. The control-diet rats without CCl4 administration were used as a normal control group. Gene expression in AL was reversed by twofold greater than in LC in the microarray were selected to elucidate the improvements in nutritional and metabolic disorders. Downregulation of fatty acid translocase (FAT)/Cd36, glutamine synthetase, and pyruvate dehydrogenase kinase isoenzyme 4 is believed to promote lower uptake of fatty acids, lower ammonia incorporation, and higher uptake of glucose, and thus to provide an energy source without using BCAA. Ultimately, the catabolism of BCAA and skeletal muscle protein would be slowed, maintaining BCAA concentrations in blood. Conclusion: We established, for the first time, the regulatory gene pathways of processes involved in hepatic fibrosis and energy metabolism (hypoalbuminemia, hyperammonemia, and carbohydrate catabolism, and their relationships) under BCAA supplementation. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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

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

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

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

Sasa S.-I.,Tokyo University of Science
Journal of Physics A: Mathematical and Theoretical | Year: 2012

Lattice molecule models are proposed in order to study statistical mechanics of glass transition in finite dimensions. Molecules in the models are represented by hard Wang tiles and their density is controlled by a chemical potential. An infinite series of irregular ground states are constructed theoretically. By defining a glass order parameter as a collection of the overlap with each ground state, a thermodynamic transition to a glass phase is found in a stratified Wang tiles model on a cubic lattice. Source

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

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

Okano K.,Tokyo University of Science
Journal of Mathematical Cryptology | Year: 2012

The parameter ρ of a complete family of pairing-friendly elliptic curves represents how suitable some given elliptic curves are in pairing-based cryptographic schemes. The superiority of the curves depends on how close ρ is to 1. Especially, the situation ρ = 1 is ideal. We study whether a complete family of pairing-friendly elliptic curves has a ρ-value 1 or not. In this paper, we consider the original idea of Brezing and Weng that we put a parameter r(x) for constructing families of elliptic curves as cyclotomic polynomials. We show that the ρ-values cannot be 1 in many cases. © de Gruyter 2012. Source

Zuhdi U.,Tokyo University of Science | Zuhdi U.,Bandung Institute of Technology
Advanced Science Letters | Year: 2014

The purpose of this study is to get the other perspective related to the role of Information and Communication Technologies (ICT) sectors in national economy of Japan from 1995 through 2005. This study employs input- output analysis as a tool of analysis. Results show that the role of those sectors in Japanese national economy on that period can be different if comparison related to that using other method is conducted. The other perspective related to that role is obtained from this study, namely ICT sectors, using simple output multipliers method, do not have an important role in national economy of Japan from 1995 through 2005. © 2014 American Scientific Publishers All rights reserved. Source

Some general aspects of nonlinear transport phenomena are discussed on the basis of two kinds of formulations obtained by extending Kubo's perturbational scheme of the density matrix and Zubarev's non-equilibrium statistical operator formulation. Both formulations are extended up to infinite order of an external force in compact forms and their relationship is clarified through a direct transformation. In order to make it possible to apply these formulations straightforwardly to thermal disturbance, its mechanical formulation is given (in a more convenient form than Luttinger's formulation) by introducing the concept of a thermal field E T which corresponds to the temperature gradient and by defining its conjugate heat operator A H= ∑ j hjr j for a local internal energy hj of the thermal particle j. This yields a transparent derivation of the thermal conductivity κ of the Kubo form and the entropy production ( dSdt)irr=κET2T. Mathematical aspects of the non-equilibrium density-matrix will also be discussed. In Paper I (M. Suzuki, Physica A 390 (2011)1904), the symmetry-separated von Neumann equation with relaxation terms extracting generated heat outside the system was introduced to describe the steady state of the system. In this formulation of the steady state, the internal energy 〈 H0〉t is time-independent but the field energy 〈 H1〉t(=- 〈A〉t·F) decreases as time t increases. To overcome this problem, such a statisticalmechanical formulation is proposed here as includes energy supply to the system from outside by extending the symmetry-separated von Neumann equation given in Paper I. This yields a general theory based on the density-matrix formulation on a steady state with energy supply inside and heat extraction outside and consequently with both 〈 H0〉t and 〈 H1〉t constant. Furthermore, this steady state gives a positive entropy production. The present general formulation of the current yields a compact expression of the time derivative of entropy production, which yields the plausible justification of the principle of minimum entropy production in the steady state even for nonlinear responses. © 2011 Elsevier B.V. All rights reserved. Source

Kneller R.,Tokyo University of Science
Nature Reviews Drug Discovery | Year: 2010

Understanding the factors that promote drug innovation is important both for improvements in health care and for the future of organizations engaged in drug discovery research and development. By identifying the inventors of 252 new drugs approved by the US Food and Drug Administration from 1998 to 2007 and their places of work, and also classifying these drugs according to innovativeness, this study investigates the contribution of different types of organizations and regions to drug innovation during this period. The data indicate that drugs initially discovered in biotechnology companies or universities accounted for approximately half of the scientifically innovative drugs approved, as well as half of those that responded to unmet medical needs, although their contribution to the total number of new drugs was proportionately lower. The biotechnology companies were located mainly in the United States. This article presents a comprehensive analysis of these data and discusses potential contributing factors to the trends observed, with the aim of aiding efforts to promote drug innovation. © 2010 Macmillan Publishers Limited. All rights reserved. Source

Tsujikawa S.,Tokyo University of Science