Funabashi H.,Hiroshima University
Electrochemistry | Year: 2016
Single-stranded deoxyribonucleic acid (ssDNA) with guanine-rich sequences can form four-stranded structures so called G-quadruplex (Gq), which binds hemin, an iron-containing porphyrin. The hemin/Gq is an electroactive complex and exhibits peroxidase activity, and thus the hemin/Gq complexes have attracted great attention as a signal generator. This short review surveys the use of the hemin/Gq complex as an electrochemical signal generator. Electrochemical methods for detecting the hemin/Gq complex, approaches to signal amplification, and targeting strategies are herein discussed. Compared with protein-based signal generators, hemin/Gq complexes have some advantages: a wide variety of ssDNA sequences with various chemical modifications are easy to obtain, they can be immobilized on an electrode easily, and they can be designed as desired to connect functional domains. Also there are many molecular-biological tools to handle them. Hemin/Gq complexes have been successfully used to detect bioanalytes ranging from low molecular weight compound to macromolecules such as proteins, specific nucleic acids, or living cancer cells. Such bioanalytes are critical to the investigation of cellular function. Thus, DNAbased probes that contain hemin/Gq as a signal generator are a promising tool for the electrochemical analysis of cellular function, offering a competent alternative to a conventional protein-based signal generator. © 2016 The Electrochemical Society of Japan, All rights reserved.
Itoh T.,Hiroshima University
Bulletin of the Chemical Society of Japan | Year: 2014
Change of the emission spectrum of anisaldehyde vapor has been investigated as a function of irradiation time by exposing a sample to UV light for different times. It is shown that there is a new photochemical channel for anisaldehyde (p-methoxybenzaldehyde) vapor to form benzaldehyde vapor upon the photoexcitation into the S2 state.
Imura K.-I.,Hiroshima University |
Fukui T.,Ibaraki University |
Fujiwara T.,Ibaraki University
Nuclear Physics B | Year: 2012
We study a Majorana zero-energy state bound to a hedgehog-like point defect in a topological superconductor described by a Bogoliubov-de Gennes (BdG)-Dirac type effective Hamiltonian. We first give an explicit wave function of a Majorana state by solving the BdG equation directly, from which an analytical index can be obtained. Next, by calculating the corresponding topological index, we show a precise equivalence between both indices to confirm the index theorem. Finally, we apply this observation to reexamine the role of another topological invariant, i.e., the Chern number associated with the Berry curvature proposed in the study of protected zero modes along the lines of topological classification of insulators and superconductors. We show that the Chern number is equivalent to the topological index, implying that it indeed reflects the number of zero-energy states. Our theoretical model belongs to the BDI class from the viewpoint of symmetry, whereas the spatial dimension d of the system is left arbitrary throughout the paper. © 2011 Elsevier B.V.
Tomaschitz R.,Hiroshima University
EPL | Year: 2012
The superluminal neutrino velocity measured by the OPERA experiment is explained in a non-relativistic spacetime conception. Spacetime is viewed as a permeable medium of wave propagation. The neutrino wave equation is coupled to a permeability tensor, like electromagnetic fields in dielectric media. The inertial frame in which this tensor is isotropic defines a distinguished frame of reference, the rest frame of the aether. The dispersion relation of the spinorial wave modes gives rise to a superluminal group velocity of the energy flux. The Gordon decomposition of spinor currents in a refractive and dispersive spacetime is performed with finite as well as zero rest mass. The convective and spin components of the superluminal neutrino current are related to the permeability tensor. The refractive index of the aether depends on the neutrino energy, and is inferred in the 10 to 50 GeV range from the measured excess velocity. Implications of the superluminal speed of signal transfer regarding relativity principles and causality are discussed. Copyright © EPLA, 2012.
Fujii H.,Hiroshima University
Nihon rinsho. Japanese journal of clinical medicine | Year: 2013
Some meta-analysis on smoking and risk of stroke showed that current smoking raised risks of total stroke, subarachnoid hemorrhage, and ischemic stroke but did not raise risk of intraparenchymal hemorrhage. On the other hand, previous meta-analysis showed that smoking was inversely associated with risk of Parkinson's disease. Early research found that nicotine improved short-term cognitive function and inhibited amyloid formation. More recently, it has showed with meta-analysis that smoking raised risk of Alzheimer's disease. Cigarette smoking has a disadvantage for neurological disorders.
Kitadai Y.,Hiroshima University
Journal of Oncology | Year: 2010
Tumor angiogenesis is the result of an imbalance between positive and negative angiogenic factors released by tumor and host cells into the microenvironment of the neoplastic tissue. The stroma constitutes a large part of most solid tumors, and cancer-stromal cell interactions contribute functionally to tumor growth and metastasis. Activated fibroblasts and macrophages in tumor stroma play important roles in angiogenesis and tumor progression. In gastric cancer, tumor cells and stromal cells produce various angiogenic factors, including vascular endothelial growth factor, interleukin-8, platelet-derived endothelial cell growth factor, and angiopoietin. In addition, Helicobacter pylori infection increases tumor cell expression of metastasis-related genes including those encoding several angiogenic factors. We review the current understanding of molecular mechanisms involved in angiogenesis and lymphangiogenesis of human gastric cancer. © 2010 Yasuhiko Kitadai.
Imaizumi K.,Hiroshima University
Clinical calcium | Year: 2013
The endoplasmic reticulum (ER) is a central cellular organelle responsible for the synthesis, folding and posttranslational modifications of proteins destined for the secretory pathway. Various pathophysiological conditions, such as ER-calcium depletion, oxidative stress, hypoglycemia, expression of mutated proteins and hypoxia, interfere with the correct folding of proteins and these misfolded or unfolded proteins accumulate in the ER lumen. These conditions, which are collectively termed ER stress, have the potential to induce cellular damage. Recently, the ER stress has been demonstrated to be associated with bone and cartilage diseases. Further, it has been known that the ER stress and its stress response also play important roles in osteogenesis and chondrogenesis.
Ikehata M.,Hiroshima University
Inverse Problems | Year: 2014
This paper considers an inverse problem for the classical wave equation in an exterior domain. It is a mathematical interpretation of an inverse obstacle problem which employs the dynamical scattering data of an acoustic wave over a finite time interval. It is assumed that the wave satisfies a Robin-type boundary condition with an unknown variable coefficient. The wave is generated from the initial data localized outside the obstacle and observed over a finite time interval at the same place as the support of the initial data. It is already known that, using the enclosure method, one can extract the maximum sphere whose exterior encloses the obstacle, from the data. In this paper, it is shown that the enclosure method enables us to extract also: (i) a quantity which indicates the deviation of the geometry between the maximum sphere and the boundary of the obstacle at the first-reflection points of the wave; (ii) the value of the coefficient of the boundary condition at an arbitrary first-reflection point of the wave provided, for example, that the surface of the obstacle is known in a neighbourhood of the point. Further new knowledge is obtained as follows: the enclosure method can cover the case where the data are taken over a sphere whose centre coincides with that of the support of an initial datum, and yields results corresponding to (i) and (ii). © 2014 IOP Publishing Ltd.
Shinkai S.,Hiroshima University
Journal of the Physical Society of Japan | Year: 2015
We give a decomposition expression for dissipative heat using the instantaneous diffusion coefficient in a nonequilibrium steady state. The dissipative heat can be expressed using three diffusion coefficients: instantaneous, equilibrium, and drift. An experimental application of the decomposition expression permits us to evaluate the heat dissipation rate from single-trajectory data only. We also numerically demonstrate this method. © 2015 The Physical Society of Japan.
Hayashi F.,Hiroshima University
Journal of oral science | Year: 2012
Porphyromonas gingivalis FimA fimbriae have been classified into 6 genotypes (types I-V and Ib) based on the diversity of the fimA genes encoding the fimbrial subunits. We investigated the prevalence of fimA genotype in Japanese children. Dental plaque specimens were obtained from 400 subjects (age; 2 to 15 years), including 134 with healthy gingiva, 239 with gingivitis and 27 with periodontitis, and then analyzed by polymerase chain reaction. P. gingivalis was detected in 1.5%, 10.0% and 29.6% of these subjects, respectively. Significant differences were observed with regard to P. gingivalis infection among the groups [chi-squared analysis: gingivitis vs. healthy, P < 0.01, odds ratio (OR) = 7.4; periodontitis vs. healthy, P < 0.001, OR = 27.8]. In P. gingivalis-positive subjects with periodontitis, the most prevalent fimA types were type Ib/type II combination (37.5%) and type IV (37.5%), followed by type II (25.0%), while type IV (33.3%) and type II (29.2%) were most often detected in those with gingivitis. Our results suggest that the presence of P. gingivalis is associated with periodontal diseases, and that the type II, IV and Ib/II combination are the most common among fimA genotypes.
Toyoda H.,Tokyo University of Agriculture and Technology |
Ono G.,Hiroshima University |
Nishimura S.,Laboratory in Tokyo
IEEE Communications Magazine | Year: 2010
This article discusses the logical implementation of the media access control and the physical layer of 100 Gb/s Ethernet. The target are a MAC/PCS LSI, supporting MAC and physical coding sublayer, and a gearbox LSI, providing 10:4 parallel lane-width exchange inside an optical module. The two LSIs are connected by a 100 gigabit attachment unit interface, which consists of ten 10 Gb/s lines. We realized a MAC/PCS logical circuit with a low-frequency clock on a FPGA, whose size is 250 kilo LUTs with a 5.7 Mbit RAM, and the power consumption of the gearbox LSI estimated to become 2.3 W. © 2010 IEEE.
Saeki Y.,Hiroshima University
Surgery today | Year: 2013
Hemorrhage from jejunal varices formed at the site of Roux-en-Y choledochojejunostomy is rather rare, and no guidelines have so far been established for its treatment. This report presents the cases of 2 patients with jejunal varices formed at the site of choledochojejunostomy that were treated using different methods. An obstruction of the extrahepatic portal vein resulted in massive gastrointestinal bleeding in both cases CASE 1: A 59-year-old male developed jejunal varices at the site of choledochojejunostomy. Multidetector computed tomography showed that the source of bleeding was located in the small intestine near portojejunal varices. The jejunal vein supplying the afferent loop was embolized using interventional radiology. There was no evidence of liver dysfunction or rebleeding after the embolization CASE 2: A 79-year-old female developed jejunal varices at the site of choledochojejunostomy. Abdominal angiography could not detect the source of bleeding, and hence, a mesocaval shunt operation was performed.
Yamanaka S.,Hiroshima University
Journal of Materials Chemistry | Year: 2010
The ternary metal nitride halides MNX (M = Ti, Zr, Hf; X = Cl, Br, I) contain two types of layer structured polymorphs having different types of two-dimensional metal nitride networks. Both are band insulators, and changed into superconductors with moderately high transition temperatures Tcs up to 25.5 K upon electron-doping by means of intercalation through the interlayer space. The structural characteristics, electron doping by intercalation, and the unconventional superconductivity are reviewed. © The Royal Society of Chemistry.
Hofmann H.F.,Hiroshima University |
Hofmann H.F.,Chiyoda Corporation
New Journal of Physics | Year: 2012
The density operator of a quantum state can be represented as a complex joint probability of any two observables whose eigenstates have nonzero mutual overlap. Transformations to a new basis set are then expressed in terms of complex conditional probabilities that describe the fundamental relation between precise statements about the three different observables. Since such transformations merely change the representation of the quantum state, these conditional probabilities provide a state-independent definition of the reversible and therefore effectively deterministic relations between the outcomes of different quantum measurements, including measurements of the same property performed at different times. In this paper, it is shown how classical reality emerges as an approximation to the fundamental laws of quantum determinism expressed by complex conditional probabilities. The quantum mechanical origin of phase spaces and trajectories is identified and implications for the interpretation of quantum measurements are considered. It is argued that the transformation laws of quantum determinism provide a fundamental description of the measurement dependence of empirical reality. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
Shimizu Y.,Hiroshima University
Modern Physics Letters A | Year: 2012
A method to apply the tensor renormalization group to a lattice boson model is proposed. It is based on the truncated singular value decomposition of a compact operator. We demonstrate it using the (1+1)-dimensional φ 4 model. The evaluated critical points on the lattice are consistent with the Monte Carlo result. © 2012 World Scientific Publishing Company.
Mukaidani H.,Hiroshima University
Asian Journal of Control | Year: 2011
This paper investigates a novel design method for robust nonfragile proportional-integral-derivative (PID) control that is based on the guaranteed cost control (GCC) problem for a class of uncertain discrete-time stochastic systems with additive gain perturbations. On the basis of linear matrix inequality (LMI), a class of fixed PID controller parameters is obtained, and some sufficient conditions for the existence of the GCC are derived. Although the additive gain perturbations are included in the feedback systems, both the stability of closed-loop systems and adequate cost bound are attained. As a sequel, decentralized GCC PID for a class of discrete-time uncertain large-scale stochastic systems is also considered. Finally, the numerical results demonstrate the efficiency of the proposed controller synthesis. © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society.
Han H.,Hiroshima University
IEEJ Transactions on Electronics, Information and Systems | Year: 2011
In recent years, there have been significant advances in the study of the stability analysis and controller synthesis for the so-called Takagi-Sugeno (T-S) fuzzy model, which have been used to represent certain complex nonlinear systems. In the T-S fuzzy model, the local dynamics in different state-space regions are represented by linear models such as (t) = A ix(t)+Biu(t), where A i,B i are certain known matrices with some appropriate dimensions. © 2011 The Institute of Electrical Engineers of Japan.
Takane Y.,Hiroshima University
Journal of the Physical Society of Japan | Year: 2015
A three-dimensional weak topological insulator (WTI), being equivalent to stacked layers of two-dimensional quantum spin-Hall insulators, accommodates massless Dirac electrons on its side surface. A notable feature of WTIs is that surface states typically consist of two Dirac cones in the reciprocal space. We study the Landau quantization of Dirac electrons of WTIs in a perpendicular magnetic field. It is shown that when the magnetic length lB is much larger than the interlayer distance a, surface electrons are quantized into Landau levels according to the ordinary quantization rule for Dirac electrons. It is also shown that, with decreasing lB toward a, each Landau level and its spin state become modulated in a nontrivial manner. We demonstrate that this is attributed to the mixing of two Dirac cones induced by the discreteness of the layered structure. ©2015 The Physical Society of Japan.
Saito A.,Hiroshima University
Clinical calcium | Year: 2013
Various cellular conditions such as synthesis of abundant proteins, expressions of mutant proteins and oxidative stress lead to accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) lumen. This type of stress is called ER stress. The excessive ER stress causes cellular damages followed by apoptosis. When ER stress occurs, cells are activated ER stress response (unfolded protein response) to avoid cellular damages. Recently, it has been clear that ER stress response plays crucial roles not only in cell survival after ER stress but also in regulating various cellular functions and tissue formations. In particular, ER stress and ER stress response regulate protein quality control, secretory protein production, and smooth secretion of proteins in the cells such as osteoblasts which synthesize and secrete enormous matrix proteins.
Alaiti M.A.,Case Western Reserve University |
Ishikawa M.,Hiroshima University |
Costa M.A.,Case Western Reserve University
Translational Research | Year: 2010
Cardiovascular disease is the leading cause of death and disability in the Western world. In addition to the advancement of current therapeutic approaches to reduce the associated morbidity and mortality, regenerative medicine and cell-based therapy have been areas of continuous investigation. Circulating and bone-marrow-derived stem or endothelial progenitor cells are an attractive source for regenerative therapy in the cardiovascular field. In this review, we highlight the advantages and limitations of this approach with a focus on key observations from animal studies and clinical trials. © 2010 Mosby, Inc. All rights reserved.
Kakuwa J.,Hiroshima University
Astrophysical Journal | Year: 2016
Stochastic acceleration of nonthermal electrons is investigated in the context of hard photon spectra of blazars. It is well known that this acceleration mechanism can produce a hard electron spectrum of ln ne (γ)/ln γ = 2 with the high-energy cutoff, called an ultrarelativistic Maxwellian-like distribution, where ne(γ) is an electron energy spectrum. We revisit the formation of this characteristic spectrum, considering a particular situation where the electrons are accelerated through gyroresonant interaction with magnetohydrodynamic wave turbulence driven by the turbulent cascade. By solving kinetic equations of the turbulent fields, electrons, and photons emitted via the synchrotron self-Compton (SSC) process, we demonstrate that in the non-test-particle treatment, the formation of a Maxwellian-like distribution is prevented by the damping effect on the turbulent fields due to the electron acceleration, at least unless an extreme parameter value is chosen. Instead, a softer electron spectrum with the index of m ≈ -1 is produced if the Kolmogorov-type cascade is assumed. The SSC spectrum that originates from the resultant softer electron spectrum is still hard, but somewhat softer and broader than the case of m = 2. This change of achievable hardness should be noted when this basic particle acceleration scenario is accurately tested with observations of hard photon spectra. © 2016. The American Astronomical Society. All rights reserved.
Hayakawa K.,Hiroshima University
Computational Statistics and Data Analysis | Year: 2015
Improved IV/GMM estimators for panel vector autoregressive models (VAR) are proposed. It is shown that the proposed IV estimator has the same asymptotic distribution as the bias-corrected fixed effects estimator in the VAR(1) case when both the sample sizes of cross section and time series are large. Since the proposed estimator is simply to change the form of instruments, it is very easy to implement in practice. As applications of the proposed estimators, a panel Granger causality test and panel impulse response analysis in which the asymptotic distribution of generalized impulse response functions is newly derived are considered. Monte Carlo simulation results show that the proposed estimators have comparable or better finite sample properties than the conventional IV/GMM estimators using instruments in levels for moderate or long time periods. © 2015 Elsevier B.V.
Ohishi W.,Radiation Effects Research Foundation |
Chayama K.,Hiroshima University
Hepatology Research | Year: 2012
Recently antiviral therapies for chronic hepatitis B using nucleos(t)ide analogues have become standard treatment modalities on the basis of several independent guidelines, starting with those of the American Association for the Study of Liver Diseases (AASLD) and other such organizations and bodies, including the European Association for the Study of the Liver (EASL), the Asian Pacific Association for the Study of the Liver (APASL), and the Japanese Ministry of Health, Labour and Welfare (MHLW)'s research team. The philosophies underlying such treatment strategies are considered basically equivalent. MHLW's guidelines define subjects for medical intervention to be cases measuring alanine aminotransferase (ALT) ≥31IU/L, with serological hepatitis B virus (HBV) DNA level ≥5log copies/mL for hepatitis B e antigen (HBeAg)-positive cases, and serological HBV DNA level ≥4log copies/mL for HBeAg-negative cases. These Japanese guidelines advocate entecavir as the first-line treatment option for nucleos(t)ide-naïve patients, and combination treatment of lamivudine and adefovir as the basis of treatment for patients with lamivudine- and/or entecavir-resistant viruses. Of particular note for patients undergoing lamivudine treatment with persistent HBV DNA level<2.1log copies/mL is the recommendation of a switch to entecavir. Early detection of drug-resistant virus is desirable after initiation of nucleos(t)ide analogue treatment, but such a procedure is not uniformly available at all medical institutions. Nevertheless, timely estimation of potential early-stage drug-resistant virus development is crucial for getting a head start on treatment. HBV core-related antigen (HBcrAg) level or HBV DNA level are considered useful markers for the appearance of such drug-resistant viruses. © 2011 The Japan Society of Hepatology.
Mabuhay J.A.,Mindanao State University |
Nakagoshi N.,Hiroshima University
Landscape and Ecological Engineering | Year: 2012
Japan has suffered a lot from forestry losses due to pine wilt disease caused by pinewood nematode infestations. Studies were conducted regarding its causative agent and the effects of natural vegetation succession after pine wilt disease, but its effects on microorganisms were not given equal attention. This study determined the effects of pine wilt disease on light conditions, soil microbial biomass, litter decomposition, microbial abundance and the physical and chemical properties of the soil. Results showed that in a forest currently affected by pine wilt disease, there was higher light penetration, greater microbial biomass carbon, and a faster rate of litter decomposition. Microbial abundance was shown to be reduced in pine wilt affected areas. There were close correlations between the biological and physicochemical properties of the soil, but the reason for the decrease in microbial abundance is not yet well understood, and thus requires further study. © 2011 International Consortium of Landscape and Ecological Engineering and Springer.
Yamada T.,Kyoto University |
Izui K.,Kyoto University |
Nishiwaki S.,Kyoto University |
Takezawa A.,Hiroshima University
Computer Methods in Applied Mechanics and Engineering | Year: 2010
This paper proposes a new topology optimization method, which can adjust the geometrical complexity of optimal configurations, using the level set method and incorporating a fictitious interface energy derived from the phase field method. First, a topology optimization problem is formulated based on the level set method, and the method of regularizing the optimization problem by introducing fictitious interface energy is explained. Next, the reaction-diffusion equation that updates the level set function is derived and an optimization algorithm is then constructed, which uses the finite element method to solve the equilibrium equations and the reaction-diffusion equation when updating the level set function. Finally, several optimum design examples are shown to confirm the validity and utility of the proposed topology optimization method. © 2010 Elsevier B.V.
Yoshida H.,Hiroshima University
Synthesis (Germany) | Year: 2016
Because of the high synthetic significance of organostannanes, much attention has been focused on the development of stannylation reactions endowed with high chemo-, regio-, and stereoselectivities. This review highlights recent advances in catalytic C–Sn bond-forming reactions especially with base metal complexes, intended to attract the readers’ attention to the unique base metal catalysis in the stannylation, thereby encouraging future progress in this field. 1 Introduction 2 Co Catalysis 3 Ni Catalysis 4 Cu Catalysis 5 Zn Catalysis 6 Mo Catalysis 7 W Catalysis 8 Conclusion Copyright © 2016, Georg Thieme Verlag. All rights reserved.
Morimoto Y.,Hiroshima University
International Journal of Computational Science and Engineering | Year: 2010
We considered co-location pattern mining algorithm that uses the Voronoi diagram. In general, the density of spatial objects is much higher in urban areas than in rural areas. The proposed algorithm is suitable for such unevenly distributed database. We have applied the co-location pattern mining algorithm for real spatial databases and show the capability of the proposed algorithm for a real spatial database. We also applied our methods for analysing web pages that contains spatial information. There are many web pages that contain spatial information such as addresses, postal codes, and telephone numbers. Most of the spatial information in web pages are location information and is unevenly distributed. We collected such web pages by web-crawling programs. For each page determined to contain location information, we apply geocoding techniques to compute geographic coordinates, such as latitude-longitude pairs. Next, we augment the location information with keyword descriptors extracted from the web page contents. We then apply co-location mining on the augmented location information. Copyright © 2010 Inderscience Enterprises Ltd.
Barles G.,University of Tours |
Ishii H.,Waseda University |
Ishii H.,King Abdulaziz University |
Mitake H.,Hiroshima University
Archive for Rational Mechanics and Analysis | Year: 2012
In this article, we study the large time behavior of solutions of first-order Hamilton-Jacobi Equations set in a bounded domain with nonlinear Neumann boundary conditions, including the case of dynamical boundary conditions. We establish general convergence results for viscosity solutions of these Cauchy-Neumann problems by using two fairly different methods: the first one relies only on partial differential equations methods, which provides results even when the Hamiltonians are not convex, and the second one is an optimal control/dynamical system approach, named the "weak KAM approach", which requires the convexity of Hamiltonians and gives formulas for asymptotic solutions based on Aubry-Mather sets. © 2012 Springer-Verlag.
Kawai K.,Hiroshima University |
Takato S.,Tokyo University of Technology |
Sasaki T.,Japan National Agriculture and Food Research Organization |
Kajiwara K.,Tokyo University of Technology
Food Hydrocolloids | Year: 2012
Effects of the type and amount of fatty acid (0-2.0mmol/g-starch of lauric, myristic, palmitic, stearic, oleic, and linoleic acids) on the complex formation, thermal properties, and in-vitro digestibility of gelatinized potato starch-fatty acid mixtures were investigated. Complex index (CI) evaluated by the reduction in the iodine binding capacity of starch increased with an increase in the amount of fatty acids, and reached a plateau depending on the type of fatty acid. The maximum CI value was higher in the order of lauric (49.9%), linoleic (47.6%), myristic (42.4%), oleic (36.7%), stearic (35.3%), and palmitic acid (30.9%). From the calorimetric study, it was demonstrated that melting temperature of the complexes was higher in the order of stearic (96.7°C)>lauric, myristic, palmitic, and oleic (89.6-92.1°C)>linoleic acid (78.3°C). Melting enthalpy for complexes was roughly related to the CI value (R2=0.667). From the in-vitro digestibility measurement, it was found that a certain amount of fatty acid reduced the starch content hydrolyzed at a given condition. Among them, 0.50mmol/g-starch lauric and oleic acid samples showed the largest reduction in the hydrolyzed starch content. This result was related to the extent of complex formation characterized by CI value and its helical order characterized by melting temperature. In addition, there was a possibility of the complex formation between amylose and unsaturated fatty acid during the hydrolysis of gelatinized starch. © 2011 Elsevier Ltd.
Lee J.,Chongqing University |
Imai K.,Hiroshima University |
Zhu Q.-S.,Chongqing University
Information Sciences | Year: 2012
A number-conserving cellular automaton (NCCA) is a cellular automaton in which the states of cells are denoted by integers, and the sum of all of the numbers in a configuration is conserved throughout its evolution. NCCAs have been widely used to model physical systems that are ruled by conservation laws of mass or energy. Imai et al.  showed that the local transition function of NCCA can be effectively translated into the sum of a binary flow function over pairs of neighboring cells. In this paper, we explore the computability of NCCAs in which the pairwise number flows are performed at fully asynchronous timings. Despite the randomness that is associated with asynchronous transitions, useful computation still can be accomplished efficiently in the cellular automata through the active exploitation of fluctuations . Specifically, certain numbers may flow randomly fluctuating between forward and backward directions in the cellular space, as if they were subject to Brownian motion. Because random fluctuations promise a powerful resource for searching through a computational state space, the Brownian-like flow of the numbers allows for efficient embedding of logic circuits into our novel asynchronous NCCA. © 2011 Elsevier Inc. All rights reserved.
Wada N.,Hiroshima University
IEEE Transactions on Automatic Control | Year: 2015
In this technical note, we propose a model predictive tracking control algorithm for linear dynamical systems with input constraints. To achieve setpoint tracking, an integrator is inserted into the feedback loop. In the standard control strategy, integral action is used for all the time to remove steady state error. In the proposed control approach, the value of the integrator state is reset at each sampling time to improve tracking control performance until upper bound of the cost becomes sufficiently small. Then, the integral action is used to achieve offset-free tracking. The control algorithm is reduced to a convex optimization problem under linear matrix inequality constraints. © 1963-2012 IEEE.
Liu C.,Japan International Center for Materials Nanoarchitectonics |
Minari T.,Japan International Center for Materials Nanoarchitectonics |
Lu X.,Japan International Center for Materials Nanoarchitectonics |
Kumatani A.,Japan International Center for Materials Nanoarchitectonics |
And 2 more authors.
Advanced Materials | Year: 2011
Simple solvent-vapor annealing was used to fabricate single crystals of dioctylbenzothienobenzothiophene on a polymer dielectric surface. By involving self-organized phase separation, crystal length is enhanced and a good semiconductor/insulator interface is obtained. The field-effect transistors (FETs) exhibit an average p-type FET mobility of 3.0 cm2 V -1 s-1, with a highest value of 9.1 cm2 V -1 s-1. The FET mobility increases as temperature decreases, which suggests intrinsic bandlike transport. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Moriya J.,Rikkyo University |
Sugiura Y.,Hiroshima University
Frontiers in Human Neuroscience | Year: 2013
Socially anxious individuals are interfered by distractors. Recent work has suggested that low working memory capacity and inappropriate temporary goal induce attention to distractors. We investigated the effects of working memory capacity and temporary goal on attention to distractors in social anxiety. Participants viewed a rapid serial visual presentation, in which participants reported the identity of a single target letter drawn in red. Distractors appeared before the target was presented. When the color of distractors was red (i.e., goal-relevant stimuli), low-capacity individuals were strongly interfered by the distractors compared to high-capacity individuals regardless of social anxiety. When the color of distractors was goal-irrelevant, low-capacity and high socially anxious individuals were strongly interfered by the distractors. These results suggest that socially anxious individuals with low working memory capacity could not inhibit the goal-irrelevant information and direct attention to distractors. © 2013 Moriya and Sugiura.
Kano M.,University of Tokyo |
Hashimoto K.,University of Tokyo |
Hashimoto K.,Hiroshima University
Cerebellum | Year: 2012
Cerebellar Purkinje cells (PCs) of newborn rodents are innervated by multiple climbing fibers (CFs). During the first postnatal week, single CFs are strengthened relative to other CFs on the somata of individual PCs. Then, the strengthened CFs undergo translocation to PC dendrites after P9. Elimination of the weaker CFs occurs in two distinct steps, namely the early phase from P7 to around P12 and the late phase from about P12 to around P17. Our previous study demonstrates that CF synapse elimination is severely impaired in nullmutant mice lacking Cav2.1, a pore-forming component of P/Q-type voltage-dependent Ca2+ channel (VDCC). To examine the contribution of postsynaptic P/Q-type VDCC to postnatal rearrangement of CFs, we generated mice with PCselective deletion of Cav2.1 (PC-Cav2.1 KO). We made whole-cell recordings from PCs in cerebellar slices and examined CF-mediated excitatory postsynaptic currents. We found that PC-Cav2.1 KO PCs had severe defects in selective strengthening of single CFs during the first postnatal week and subsequent CF synapse elimination from P7. Moreover, our morphological analysis revealed that multiple CFs abnormally underwent translocation to PC dendrites in PCCav2.1 KO mice. These results indicate that Ca2+ influx through P/Q-type VDCC into PCs is crucial for selective strengthening of single CFs, early phase elimination and selective translocation of single strengthened CFs to PC dendrites. ©Springer Science+Business Media, LLC 2011.
Meddah M.S.,Kingston University |
Suzuki M.,Mitsubishi Group |
Sato R.,Hiroshima University
Construction and Building Materials | Year: 2011
High-performance concrete (HPC) is characterized by its low water-to-cementitious materials (w/cm) and improved properties but also it exhibits high internal capillary tensile stress because the development of autogenous shrinkage which could result in early-age cracking risk and premature deterioration. Since the use of HPC in structural elements has gained wide acceptance in the last decades, the large magnitude of early-age autogenous strains and stresses has to be mitigated to enhance the durability of concrete structure. In this paper, internal stress development induced during the development of autogenous shrinkage strains, especially at early-age was investigated on three different types of HPC cured with a combination of two shrinkage-compensating admixtures. Binary HPC made with blended cement containing 10% of silica fume (SF) has been used with three different low (w/c + sf) of 0.15, 0.23, and 0.30. Shrinkage-reducing agent (SRA) and an expansive additive (EXA) were combined and added to the HPC mixtures to minimize autogenous shrinkage magnitude. The results indicate that the greater the autogenous shrinkage developed, the higher the induced internal tensile stress. It has been found that for the reference mixes, more than 90% of the ultimate magnitude of both autogenous shrinkage and self-tensile stress was developed during the first 24 h. However, the addition of a combination of SRA and EXA has resulted in a significant reduction and a gradual development of both autogenous shrinkage and self-tensile stress as compared to the rapid development and large magnitude in the reference concretes. Moreover, a high dimensional stability was obtained for the 0.30 and 0.23 HPC mixtures containing the combination of expansive and shrinkage-reducing admixtures. On the other hand, a slight decrease of the compressive, of the splitting tensile strengths and the modulus of elasticity was observed. © 2010 Elsevier Ltd. All rights reserved.
Fitriadhy A.,University of Malaysia, Terengganu |
Yasukawa H.,Hiroshima University |
Koh K.K.,University of Technology Malaysia
Ocean Engineering | Year: 2013
This paper proposes a numerical model for analyzing the course stability of a towed ship in uniform and constant wind. The effects of an unstable towed ship and a stable towed ship were recorded using numerical analysis at various angles and velocities of wind. The stability investigation of the ship towing system was discussed using the linear analysis, where a tug's motion was assumed to be given. When the tug and the towed ship's motions were coupled through a towline as a proper model of the ship towing system, their dynamic interactions during towing was then captured using towing trajectories and analyzed using nonlinear time-domain simulation. With increasing wind velocity, the simulation results revealed that the towing instability of the unstable towed ship was recovered in the range of beam to quartering winds; however, the towing stability of the stable towed ship in head and following winds gradually degraded. It should be noted that this towing instability might have resulted in the impulsive towline tension and could led to serious towing accident e.g. towline breakage or collisions. © 2013 Elsevier Ltd. All rights reserved.
Itoh T.,Hiroshima University
Molecular Physics | Year: 2015
Fluorescence, fluorescence excitation and absorption spectra of 1,3,5-heptatrienylbenzene (MPP3) have been measured in the static vapour phase and in solution. It is shown that the MPP3 vapour exhibits prompt S2 and S1 fluorescence. The presence of two different mechanisms for the occurrence of the S2 fluorescence is demonstrated for MPP3. That is, the S2 fluorescence in the vapour phase is prompt fluorescence, the rate of which is fast enough to compete with internal conversion from S2 to S1, while in solution the S2 fluorescence occurs as the result of the thermal activation of the S1 state. The relaxation processes were discussed and the fluorescence property was compared with that of diphenylhexatriene. © 2015 Taylor & Francis
Dietary fat and bile juice, but not obesity, are responsible for the increase in small intestinal permeability induced through the suppression of tight junction protein expression in LETO and OLETF rats
Suzuki T.,Hokkaido University |
Suzuki T.,Hiroshima University |
Hara H.,Hokkaido University
Nutrition and Metabolism | Year: 2010
Background. An increase in the intestinal permeability is considered to be associated with the inflammatory tone and development in the obesity and diabetes, however, the pathogenesis of the increase in the intestinal permeability is poorly understood. The present study was performed to determine the influence of obesity itself as well as dietary fat on the increase in intestinal permeability. Methods. An obese rat strain, Otsuka Long Evans Tokushima Fatty (OLETF), and the lean counter strain, Long Evans Tokushima Otsuka (LETO), were fed standard or high fat diets for 16 weeks. Glucose tolerance, intestinal permeability, intestinal tight junction (TJ) proteins expression, plasma bile acids concentration were evaluated. In addition, the effects of rat bile juice and dietary fat, possible mediators of the increase in the intestinal permeability in the obesity, on TJ permeability were explored in human intestinal Caco-2 cells. Results. The OLETF rats showed higher glucose intolerance than did the LETO rats, which became more marked with the prolonged feeding of the high fat diet. Intestinal permeability in the OLETF rats evaluated by the urinary excretion of intestinal permeability markers (Cr-EDTA and phenolsulfonphthalein) was comparable to that in the LETO rats. Feeding the high fat diet increased intestinal permeability in both the OLETF and LETO rats, and the increases correlated with decreases in TJ proteins (claudin-1, claudin-3, occludin and junctional adhesion molecule-1) expression in the small, but not in the large intestine (cecum or colon). The plasma bile acids concentration was higher in rats fed the high fat diet. Exposure to bile juice and the fat emulsion increased TJ permeability with concomitant reductions in TJ protein expression (claudin-1, claudin-3, and junctional adhesion molecule-1) in the Caco-2 cell monolayers. Conclusion. Excessive dietary fat and/or increased levels of luminal bile juice, but not genetic obesity, are responsible for the increase in small intestinal permeability resulting from the suppression of TJ protein expression. © 2010 Suzuki and Hara; licensee BioMed Central Ltd.
Nishikawa M.,University of Tokyo |
Kume S.,Hiroshima University |
Nishihara H.,University of Tokyo
Physical Chemistry Chemical Physics | Year: 2013
This paper summarizes the results of our recent studies on the development of an artificial molecular rotor system that exhibits a change in redox potential and photoluminescence in response to external stimuli such as heat and photons. The molecular rotor is made of copper complexes bearing two bidentate ligands; the rotor is described here as [Cu(Rpmpy)(Lx)]+, where Rpmpy and Lx are a 4-methyl-2-(2′-pyridyl)pyrimidine derivative and a bidendate ligand with bulky moieties, x, respectively, and the pyrimidine ring can rotate beside the copper centre while maintaining the pyridine-copper connection. The simplicity of the system enabled us to design the rotating motion more accurately. We expected that placing a wall in the rotational trajectory in the Lx moiety would decrease the rate of the rotational dynamics. This slow rate of rotation was a key factor in achieving an external-stimuli-induced switching from thr equilibrium to metastable states. This switching was based on four stable isomers derived from the rotation and oxidation states, the behaviours of which were characterized for isolated copper(i) complexes using spectroscopic and electrochemical measurements at several temperatures. The steric shifts arising from the ring rotation were exploited not only to exhibit well-established oxidation-triggered motion but also to modulate the rest potential of the electrode, to manipulate the intramolecular electron transfer, to develop a redox potential switch based on photo-driven rotation, and to demonstrate the dual-luminescence behaviour. © 2013 the Owner Societies.
Abe M.,Hiroshima University |
Abe M.,Japan Institute for Molecular Science |
Abe M.,Japan Science and Technology Agency
Chemical Reviews | Year: 2013
Recent development in diradical chemistry are summarized in detail. Diradicals are long-known chemical species, but they continue to be fascinating molecules because of their inherently high reactivity and their potential molecular functions, which are mainly derived from their small HOMO-LUMO energy gaps. Kinetic stabilization and thermodynamic stabilization have made it possible to isolate diradical species. The terminology of singlet and triplet states in diradicals is derived from the number of energy level in diradicals under an external magnetic field. The triplet state is the ground-state spin multiplicity for diradicals in which a large overlap integral exists between the two energetically degenerate molecular orbitals that are occupied by two electrons. Localized diradicals are key intermediates in processes involving the homolytic bond-cleavage and -formation reactions of cyclic compounds.
Shiono T.,Hiroshima University
Advances in Polymer Science | Year: 2013
This article reviews living polymerization of olefins with several dimethyltitanium complexes by the use of trialkylaluminum-free modified methylaluminoxane (dMMAO) as a cocatalyst. The excellent solubility of dMMAO allows living coordination polymerization of olefins in aliphatic hydrocarbons. A chelating diamidodimethyltitanium complex (1) conducted living polymerization of propene in heptane at 0 C to produce atactic polymer. Metal oxide-supported dMMAO was also effective as a cocatalyst for the controlled polymerization of propene with 1, where the propagation rate and the molecular weight distribution of the produced polymer were dependent on the metal oxide used. ansa-Dimethysilylene(fluorenyl)(tert-butylamido)dimethyltitanium (2) activated by dMMAO conducted living polymerization of propene at 0 C in chlorobenzene, toluene and heptane. The propagation rate and the syndiotactic(syn)-specificity of the catalyst were dependent on the solvent as follows: propagation rate, chlorobenzene > toluene > heptane; syn-specificity, chlorobenzene < toluene < heptane. The propagation rate and the syn-specificity were also dependent on the substituent on the fluorenyl ligand of 2, and a highly active and syn-specific living polymerization was achieved by the use of a 3,6-di-tert-butyl substituted complex (4). Complex 2 and its derivatives such as 4 activated by dMMAO also conducted living homo-and copolymerization of norbornene and 1-alkene in toluene, which afforded a variety of tailor-made polyolefins composed of norbornene and 1-alkene. © 2013 Springer-Verlag Berlin Heidelberg.
Namera A.,Hiroshima University |
Saito T.,Tokai University
TrAC - Trends in Analytical Chemistry | Year: 2013
Monoliths were first used as materials for chromatographic separation 20. years ago and as extraction sorbents for solid-phase extraction over 10. years ago. Recently, monolithic silica and polymers were modified to suit devices for extraction and enrichment of analytes in matrices for environmental, food and biological analyses. This approach contributed to miniaturization and automation, which can reduce the time and the cost of sample preparation. Numerous applications were demonstrated for on-line and in-line preconcentration with monoliths, and many kinds of off-line device were designed and developed. This review discusses trends in these device and applications. © 2013 Elsevier Ltd.
Haino T.,Hiroshima University
Polymer Journal | Year: 2013
In recent years, significant research effort has focused on creating supramolecular polymers that can be attained by specific host-guest interactions of the repeating units. During the supramolecular polymerization process, molecular recognition events, which are predetermined by the molecular building blocks, are highly selective and directional for defining the size, direction and dimension of the resulting supramolecular polymers. The diversity of the supramolecular building blocks ranges from small aromatic units to macrocycles. Recently, the interplay of supramolecular and polymer chemistry has led to the creation of novel supramolecular materials, which display fascinating functions such as self-healing, stimuli-responsiveness and rubber-like elastomeric properties. Supramolecular cross-linking and supramolecular block copolymerization are the methods that have been used to install fascinating and functional moieties onto polymer backbones. Currently, the development of practical supramolecular polymeric materials is an ongoing challenge for supramolecular chemists. This review will focus on the recent developments in supramolecular polymers composed of discrete repeating units, as well as novel supramolecular materials produced by the interplay of supramolecular and polymer chemistry. © 2013 The Society of Polymer Science, Japan (SPSJ) All rights reserved.
Mikhailov A.S.,Fritz Haber Institute |
Mikhailov A.S.,Hiroshima University |
Kapral R.,University of Toronto |
Kapral R.,TU Berlin
Proceedings of the National Academy of Sciences of the United States of America | Year: 2015
The cytoplasm and biomembranes in biological cells contain large numbers of proteins that cyclically change their shapes. They are molecular machines that can function as molecular motors or carry out various other tasks in the cell. Many enzymes also undergo conformational changes within their turnover cycles. We analyze the advection effects that nonthermal fluctuating hydrodynamic flows induced by active proteins have on other passive molecules in solution or membranes. We show that the diffusion constants of passive particles are enhanced substantially. Furthermore, when gradients of active proteins are present, a chemotaxis-like drift of passive particles takes place. In lipid bilayers, the effects are strongly nonlocal, so that active inclusions in the entire membrane contribute to local diffusion enhancement and the drift. All active proteins in a biological cell or in a membrane contribute to such effects and all passive particles, and the proteins themselves, will be subject to them. © 2015, National Academy of Sciences. All rights reserved.
Shiraishi F.,University of Gottingen |
Shiraishi F.,Hiroshima University
Geochimica et Cosmochimica Acta | Year: 2012
Chemical conditions favoring photosynthesis-induced CaCO 3 precipitation (PCP) was examined to provide basic knowledge for understanding ancient ocean chemistry that enabled microbial carbonate formation. First, numerical simulations were conducted to examine the property of photosynthetic increase in CaCO 3 saturation state (ΔΩ), an indicator for PCP introduced by previous studies. These simulations revealed that ΔΩ attained a high value at high Ca 2+ concentration, low ionic strength, and optimum pH and dissolved inorganic carbon (DIC) where a low-DIC effect and CO 2/CO 3 2- buffering were insignificant. Second, microelectrode measurements were conducted using cyanobacteria-dominated stromatolite to examine the property of actual PCP. Although Ca 2+ concentration and ionic strength similarly affected actual PCP, the influences of pH and DIC were quite different from what was expected from simulations: significant PCP occurred even at high DIC (up to ~300mmolL -1) where the ΔΩ increase was suppressed by CO 2/CO 3 2- buffering. Instead, actual PCP reflected the photosynthetically achieved saturation state (Ω aft), which is the sum of ΔΩ and initial saturation state (Ω bef). Thus, the chemical conditions favoring PCP is an optimum pH-DIC condition where ΔΩ achieves a high value and/or a high pH-DIC condition where Ω bef achieves a high value, in addition to a sufficiently high Ca 2+ concentration and low ionic strength. The microelectrode measurements also revealed that the photosynthetic pH increase did not always reflect the occurrence and significance of PCP. © 2011 Elsevier Ltd.
Laarman A.H.,University of Alberta |
Sugino T.,Hiroshima University |
Oba M.,University of Alberta
Journal of Dairy Science | Year: 2012
The objective of this study was to evaluate the effects of substituting high fiber byproducts for dry ground corn in calf starter on growth and rumen pH during the weaning transition. Holstein bull calves were raised on an intensified nursing program using milk replacer containing 26% CP and 18% fat. Calves were fed a texturized calf starter containing either dry ground corn at 18.8% of dry matter (DM; CRN), beet pulp replacing dry ground corn at 10.2% dietary DM (BP), or triticale dried distillers grains with solubles replacing dry ground corn and high-protein feedstuffs at 18.6% of dietary DM (DDGS) in the pellet; treatment calf starters differed only in the pellet portion. Starch concentrations of CRN, BP, and DDGS were 35.3, 33.4, and 31.4%, respectively. After a calf consumed 2.50. kg of starter for 3 consecutive days, a small ruminant rumen pH data logger was inserted orally and rumen pH was measured continuously for 4. d. Calves were then killed and rumen fluid was sampled to determine volatile fatty acid profile. No difference was found in overall average daily gain or growth rates of hip height, withers height, and heart girth. During the weaning transition, rate of increase in calf starter intake was greater for calves fed DDGS compared with those fed CRN (87.7 vs. 77.5. g/d), but lower for calves fed BP compared with CRN (68.1 vs. 77.5. g/d). The area under pH 5.8 (470 vs. 295. min × pH/d) or pH 5.2 (72.7 vs. 16.4. min × pH/d) was greater for calves fed DDGS than those fed CRN. Rumen pH profile was not affected by BP treatment compared with CRN, but calves fed BP tended to have greater water intake than those fed CRN (6.6 vs. 5.8 L/d). Volatile fatty acid profile was not affected by treatment with the exception of molar proportion of butyrate, which tended to be lower for calves fed BP compared with those fed CRN (15.0 vs. 16.6%). Hay intake was positively correlated to mean rumen pH for calves used in this study (r = 0.48). Decreasing dietary starch concentration did not mitigate rumen acidosis in calves during weaning transition, and low rumen pH did not adversely affect growth during the weaning transition. © 2012 American Dairy Science Association.
Doi H.,Carl von Ossietzky University |
Doi H.,Hiroshima University
International Journal of Biometeorology | Year: 2012
Changes in leaf phenology lengthen the growing season length (GSL, the days between leaf budburst and leaf fall) under the global warming. GSL and the leaf phenology response to climate change is one of the most important predictors of climate change effect on plants. Empirical evidence of climatic effects on GSL remains scarce, especially at a regional scale and the latitudinal pattern. This study analyzed the datasets of leaf budburst and fall phenology in Morus bombycis (Urticales), which were observed by the agency of the Japan Meteorological Agency (JMA) from 1953 to 2005 over a wide range of latitudes in Japan (31 to 44° N). In the present study, single regression slopes of leaf phenological timing and air temperature across Japan were calculated and their spatial patterns using general linear models were tested. The results showed that the GSL extension was caused mainly by a delay in leaf fall phenology. Relationships between latitude and leaf phenological and GSL responses against air temperature were significantly negative. The response of leaf phenology and GSL to air temperature at lower latitudes was larger than that at higher latitudes. The findings indicate that GSL extension should be considered with regards to latitude and climate change. © 2011 ISB.
Yu Q.,Kyushu University |
Sasaki K.,Kyushu University |
Tanaka K.,Hiroshima University |
Ohnuki T.,Japan Atomic Energy Agency |
Hirajima T.,Kyushu University
Chemical Geology | Year: 2012
The surface reactivity of biogenic birnessite is attributed to its structure. However, structural control of heavy metal adsorption on biogenic birnessite is not well understood. Here a poorly-crystalline birnessite was produced by the fungus Paraconiothyrium sp. WL-2 strain under ambient pH and temperature conditions. The structure was characterized by X-ray absorption spectroscopy and X-ray diffraction. Sorption behaviors of Co 2+ were compared with Zn 2+. The primary product of the Mn bio-oxidation is hexagonal birnessite with a turbostratic structure. XAFS analysis demonstrated that the biogenic birnessite consists of octahedral sheets with Mn(IV) as the central metal and some vacant sites. Mn(III) atoms are coordinated to some of the vacant sites in the interlayer. The adsorption of Co 2+ by the biogenic birnessite is higher than Zn 2+. The excess adsorption of Co 2+ than Zn 2+ is nearly the same as the excess release of Mn from the biogenic birnessite. These results strongly suggested that the interlayer Mn(III) can oxidize the adsorbed Co 2+ to Co 3+, resulting in excess adsorption of Co 2+ compared to Zn 2+ by biogenic birnessite. © 2012 Elsevier B.V.
Tokunaga T.,Kagoshima University |
Shoiriki M.,Kagoshima University |
Mizumo T.,Hiroshima University |
Kaneko Y.,Kagoshima University
Journal of Materials Chemistry C | Year: 2014
In this study, a low-crystalline POSS containing two types of alkylammonium groups was successfully prepared by hydrolytic condensation of a mixture of two types of amino group-containing organotrialkoxysilanes, i.e. 3-(2-aminoethylamino)propyltrimethoxysilane and 3-aminopropyltrimethoxysilane, using aqueous trifluoromethanesulfonic acid as the catalyst and solvent. Due to the low molecular symmetry of the resulting POSS compound containing two different randomly distributed side-chain groups, its crystallization was suppressed, leading to the formation of an optically transparent film. © 2014 the Partner Organisations.
Nakajima K.,Saitama University |
Fujimoto K.,Saitama University |
Fujimoto K.,Hiroshima University |
Yaoita Y.,Saitama University
Genes to Cells | Year: 2012
During amphibian metamorphosis, a series of dynamic changes occur in a predetermined order. Hind limb morphogenesis begins in response to low levels of thyroid hormone (TH) in early prometamorphosis, but tail muscle cell death is delayed until climax, when TH levels are high. It takes about 20 days for tadpoles to grow from early prometamorphosis to climax. To study the molecular basis of the timing of tissue-specific transformations, we introduced thyroid hormone receptor (TR) expression constructs into tail muscle cells of Xenopus tadpoles. The TR-transfected tail muscle cells died upon exposure to a low level of thyroxine (T4). This cell death was suggested to be mediated by type 2 iodothyronine deiodinase (D2) that converts T4 to T3-the more active form of TH. D2 mRNA was induced in the TR-overexpressing cells by low levels of TH. D2 promoter contains a TH-response element (TRE) with a lower affinity for TR. These results show that the TR transfection confers the ability to respond to physiological concentrations of TH at early prometamorphosis to tail muscle cells through D2 activity and promotes TH signaling. We propose the positive feedback loop model to amplify the cell's ability to respond to low levels of T4. © 2012 The Authors Journal compilation © 2012 by the Molecular Biology Society of Japan/Blackwell Publishing Ltd..
Yoshida N.,Tokyo Institute of Technology |
Takahashi Y.,Hiroshima University
Elements | Year: 2012
Radionuclides, such as 134Cs, 137Cs, and 131I, were released during the Fukushima Daiichi nuclear power plant accident in March 2011. Their distribution was monitored by airborne surveys and soil sampling. The most highly contaminated areas are to the northwest of the plant and in the Naka-dori region of Fukushima Prefecture; this contamination was mainly the result of wet deposition on March 15. Radionuclides were also released on March 21, and they were dispersed up to 200 km south of the plant. The Cs/I ratios are different for these two events, probably because of differences in the initial ratios in the airborne plumes and the amount of wet deposition. Numerical simulations of the dispersion process and vertical profiles of radionuclides in soils are used to describe the contamination of soils.
Hadano N.,Hiroshima University
British Journal of Cancer | Year: 2016
Background:Pancreatic ductal adenocarcinoma (PDAC) is frequently diagnosed at an advanced stage, leading to a poor prognosis. Therefore, interest in the development of non-invasive biomarkers for prognostic prediction has grown rapidly. Here, we assessed the clinical implications of v-Ki-ras2 kirsten rat sarcoma viral oncogene homolog (KRAS)-mutated circulating tumour DNA (ctDNA) as a useful surrogate biomarker in patients with resectable PDAC.Methods:We used droplet digital polymerase chain reaction to detect rare mutant tumour-derived KRAS genes in plasma cell-free DNA (cfDNA) as ctDNA. Samples were collected from 105 patients who underwent pancreatoduodenectomy for PDAC at a single institution. Overall survival (OS) was analysed according to the presence of ctDNA.Results:Among the 105 cases, ctDNA was detected in 33 (31%) plasma samples. The median OS durations were 13.6 months for patients with ctDNA (ctDNA+) and 27.6 months for patients without ctDNA. Patients who were ctDNA+ had a significantly poorer prognosis with respect to OS (P<0.0001).Conclusions:Our findings suggested that the presence of ctDNA in plasma samples could be an important and powerful predictor of poor survival in patients with PDAC. Accordingly, ctDNA detection might be a promising approach with respect to PDAC treatment.British Journal of Cancer advance online publication, 9 June 2016; doi:10.1038/bjc.2016.175 www.bjcancer.com. © 2016 Cancer Research UK
Hashimoto K.,Hiroshima University |
Hashimoto K.,Japan Science and Technology Agency |
Kano M.,University of Tokyo
Cellular and Molecular Life Sciences | Year: 2013
Neural circuits in neonatal animals contain numerous redundant synapses that are functionally immature. During the postnatal period, unnecessary synapses are eliminated while functionally important synapses become stronger and mature. The climbing fiber (CF) to the Purkinje cell (PC) synapse is a representative model for the analysis of postnatal refinement of neuronal circuits in the central nervous system. PCs are initially innervated by multiple CFs with similar strengths around postnatal day 3 (P3). Only a single CF is selectively strengthened during P3-P7 (functional differentiation), and the strengthened CF undergoes translocation from soma to dendrites of PCs from P9 on (dendritic translocation). Following the functional differentiation, supernumerary CF synapses on the soma are eliminated, which proceeds in two distinct phases: the early phase from P7 to around P11 and the late phase from around P12 to P17. Here, we review our current understanding of cellular and molecular mechanisms of CF synapse elimination in the developing cerebellum. © 2013 The Author(s).
Kayashima T.,Saga University |
Matsubara K.,Hiroshima University
Bioscience, Biotechnology and Biochemistry | Year: 2012
Carnosic acid, a diterpene in rosemary, is considered to be beneficial in the prevention of chronic neurodegenerative diseases. Recently, it has been found that drugs with antiangiogenic activity lower the risk of neurodegenerative diseases. Thus it is of interest whether carnosic acid has antiangiogenic activity. In this study, carnosic acid suppressed microvessel outgrowth on ex vivo angiogenesis assay using a rat aortic ring at higher than 10μM. The antiangiogenic effect of carnosic acid was found in angiogenesis models using human umbilical vein endothelial cells with regard to tube formation on reconstituted basement membrane, chemotaxis and proliferation. Although the carnosol in rosemary also suppressed angiogenesis, its effect was not more potent than that of carnosic acid in the ex vivo model. These results suggest that carnosic acid and rosemary extract can be useful in the prevention of disorders due to angiogenesis, and that their antiangiogenic effect can contribute to a neuroprotective effect.
Inoue Y.,Japan Aerospace Exploration Agency |
Tanaka Y.T.,Hiroshima University
Astrophysical Journal | Year: 2016
The Fermi gamma-ray space telescope has revolutionized our understanding of the cosmic gamma-ray background radiation in the GeV band. However, investigation on the cosmic TeV gamma-ray background radiation still remains sparse. Here, we report the lower bound on the cosmic TeV gamma-ray background spectrum placed by the cumulative flux of individual detected extragalactic TeV sources including blazars, radio galaxies, and starburst galaxies. The current limit on the cosmic TeV gamma-ray background above 0.1 TeV is obtained as 2.8 10-8(E/100 GeV)-0.55 exp(-E/2100GeV)[GeV cm-2 s-1 sr-1] < E2dN/dE < 1.1 10-7(E/100 GeV)-0.49 [GeV cm-2 s-1 sr-1], where the upper bound is set by requirement that the cascade flux from the cosmic TeV gamma-ray background radiation can not exceed the measured cosmic GeV gamma-ray background spectrum. Two nearby blazars, Mrk 421 and Mrk 501, explain ∼70% of the cumulative background flux at 0.8-4 TeV, while extreme blazars start to dominate at higher energies. We also provide the cumulative background flux from each population, i.e., blazars, radio galaxies, and starburst galaxies which will be the minimum requirement for their contribution to the cosmic TeV gamma-ray background radiation. © 2016. The American Astronomical Society. All rights reserved..
Harrison M.S.,Pennsylvania State University |
Sakaguchi T.,Hiroshima University |
Schmitt A.P.,Pennsylvania State University
International Journal of Biochemistry and Cell Biology | Year: 2010
The paramyxoviruses define a diverse group of enveloped RNA viruses that includes a number of important human and animal pathogens. Examples include human respiratory syncytial virus and the human parainfluenza viruses, which cause respiratory illnesses in young children and the elderly; measles and mumps viruses, which have caused recent resurgences of disease in developed countries; the zoonotic Hendra and Nipah viruses, which have caused several outbreaks of fatal disease in Australia and Asia; and Newcastle disease virus, which infects chickens and other avian species. Like other enveloped viruses, paramyxoviruses form particles that assemble and bud from cellular membranes, allowing the transmission of infections to new cells and hosts. Here, we review recent advances that have improved our understanding of events involved in paramyxovirus particle formation. Contributions of viral matrix proteins, glycoproteins, nucleocapsid proteins, and accessory proteins to particle formation are discussed, as well as the importance of host factor recruitment for efficient virus budding. Trafficking of viral structural components within infected cells is described, together with mechanisms that allow for the selection of specific sites on cellular membranes for the coalescence of viral proteins in preparation of bud formation and virion release. © 2010 Elsevier Ltd.
Kumada H.,Toranomon Hospital |
Toyota J.,Sapporo Kosei General Hospital |
Okanoue T.,Saiseikai Suita Hospital |
Chayama K.,Hiroshima University |
And 2 more authors.
Journal of Hepatology | Year: 2012
Background & Aims: To evaluate the efficacy and safety of telaprevir in combination with peginterferon-α2b (PEG-IFN) and ribavirin (RBV) in patients with chronic hepatitis C. Methods: In a multi-center randomized clinical trial in Japan, on patients infected with HCV of genotype 1, 126 patients were assigned to telaprevir for 12 weeks along with PEG-IFN and RBV for 24 weeks (Group A), while 63 to PEG-IFN and RBV for 48 weeks (Group B). Results: HCV RNA disappeared more swiftly in patients in Group A than B, and the frequency of patients without detectable HCV RNA at week 4 (rapid virological response (RVR)) was higher in Group A than B (84.0% vs. 4.8%, p <0.0001). Grade 3 and 4 skin disorders, including Stevens-Johnson syndrome and drug rashes with eosinophilia and systemic symptoms, as well as Grade 3 anemia (<8.0 g/dl), occurred more frequently in Group A than B (skin disorders, 11.9% vs. 4.8%; anemia, 11.1% vs. 0.0%). The total RBV dose was smaller in Group A than B (47.0% vs. 77.7% of the target, p <0.0001). Despite these drawbacks, sustained virological response (SVR) was achieved more frequently in Group A than B (73.0% vs. 49.2%, p = 0.0020). Conclusions: Although the triple therapy with telaprevir-based regimen for 24 weeks resulted in more adverse events and less total RBV dose than PEG-IFN and RBV for 48 weeks, it was able to achieve higher SVR within shorter duration by carefully monitoring adverse events and modifying the RBV dose as required. © 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
Yorifuji T.,Okayama University |
Suzuki E.,Okayama University |
Kashima S.,Hiroshima University
Stroke | Year: 2014
BACKGROUND AND PURPOSE-: Few studies have examined the effect of hourly changes in air pollution on cardiovascular disease morbidity. We evaluated the associations between hourly changes in air pollution and the risks of several types of cardiovascular disease. METHODS-: We used a time-stratified case-crossover design. Study participants were 10 949 residents of the city of Okayama, Japan, aged ?65 years who were taken to hospital emergency rooms between January 2006 and December 2010 for onset of cardiovascular disease. We calculated city representative hourly average concentrations of air pollutants from several monitoring stations and examined the associations between air pollution exposure before the case event, focusing mainly on suspended particulate matter, and disease onset. RESULTS-: Suspended particulate matter exposure 0 to <6 hours before the case events was associated with risks of onset of cardiovascular and cerebrovascular disease; odds ratios after 1 interquartile range increase in suspended particulate matter exposure were 1.04 (95% confidence interval, 1.01-1.06) for cardiovascular disease and 1.04 (95% confidence interval, 1.00-1.08) for cerebrovascular disease. We observed an elevated risk of hemorrhagic as well as ischemic stroke, but the risk was slightly higher for hemorrhagic stroke, and this elevation was persistent. Women tended to have higher effect estimates. CONCLUSIONS-: This study provides further evidence that particulate matter exposure increases the risks of onset of cardiovascular and cerebrovascular disease (including hemorrhagic stroke) shortly after exposure. © 2014 American Heart Association, Inc.
Yoshida H.,Hiroshima University
ACS Catalysis | Year: 2016
Alkenylboranes have been vital reagents in modern synthetic organic chemistry, whose carbon-boron bond is transformable into a carbon-carbon bond stereoretentively to give such invaluable mutisubstituted alkenes as natural products, biologically active molecules, and functional materials. Introduction of a boryl moiety across a carbon-carbon triple bond of alkynes (borylation of alkynes) is one of the most direct and potent methods for synthesizing alkenylboranes, and this field has thus far experienced remarkable progress mainly with group 10 transition metal catalysts (Ni, Pd, Pt), which enables highly functionalized alkenylboranes to be constructed stereoselectively. On the other hand, much attention has recently been focused on the appealing catalysis of base (Fe, Co) and coinage (Cu, Ag, Au) metals toward the borylation of alkynes, which is summarized in this perspective. © 2016 American Chemical Society.
Shalaby T.,University of Zurich |
Hiyama E.,Hiroshima University |
Grotzer M.A.,University of Zurich
Anti-Cancer Agents in Medicinal Chemistry | Year: 2010
Embryonal tumours most commonly occur in the first few years of life and account for approximately 30% of childhood malignancies. Knowledge of these tumours' genetics has already impacted on their clinical management and further knowledge of their cellular immortalization will hopefully result in novel therapies. The ends of human chromosomes are capped and protected by telomeres; cellular replication, however, causes their loss. A critical length of telomere repeats is required to ensure proper telomere function and avoid the activation of DNA damage pathways that result in senescence and cell death. To proliferate beyond the senescence checkpoint, cells must restore their telomere length. Hence stabilization of telomere is an important step in cell immortalization and carcinogenesis. Telomere maintenance is evident in virtually all types of malignant cells, including embryonal tumours, where either a telomerase-dependent or alternative lengthening of telomeres (ALT) mechanism is employed in order to ensure their limitless replicative potential. For this reason effective strategies targeting telomere maintenance in cancer cells require a combination of telomerase and ALT inhibitors. In this review, we are giving an overview about telomere maintenance in childhood tumours and discussing its potential as a new therapeutic target. © 2010 Bentham Science Publishers Ltd.
Osborn K.J.,University of California at Santa Cruz |
Kuhnz L.A.,Monterey Bay Aquarium Research Institute |
Priede I.G.,University of Aberdeen |
Urata M.,Hiroshima University |
And 2 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2012
Enteropneusts (phylum Hemichordata), although studied extensively because of their close relationship to chordates, have long been considered shallow-water, burrowing animals. The present paper more than doubles the number of enteropneust species recorded in the deep sea based on high-resolution imaging and sampling with remotely operated vehicles. We provide direct evidence that some enteropneusts are highly mobile-using changes in posture and currents to drift between feeding sites-and are prominent members of deep, epibenthic communities. In addition, we provide ecological information for each species. We also show that despite their great morphological diversity, most deep-living enteropneusts form a single clade (the rediagnosed family Torquaratoridae) on the basis of rDNA sequences and morphology of the proboscis skeleton and stomochord. The phylogenetic position of the torquaratorids indicates that the group, after evolving from near-shore ancestors, radiated extensively in the deep sea © 2011 The Royal Society.
Hong J.,Wuhan University of Technology |
Enami Y.,Hiroshima University
Journal of Lightwave Technology | Year: 2011
The model and dynamic numerical solution of microring resonator modulators with feedback waveguide coupling are proposed and used to analyze the modulation performance. The sinusoidal intensity modulation output and bandwidth are presented. The feedback arm modulation manner is potential to ensure stable output with frequency increasing and wide bandwidth. Phase characteristics studies show that the resonator is suitable for phase shift keying. Furthermore, the Gaussian pulse modulation is studied. Results show that linear and undistorted output can be achieved for narrow and high speed pulse modulation while the resonator is biased at critical coupling position. © 2006 IEEE.
Yorifuji T.,Okayama University of Science |
Kashima S.,Hiroshima University
Journal of Occupational and Environmental Medicine | Year: 2013
Objective: Evidence linking short-term exposure to outdoor air pollution with hemorrhagic stroke is inconclusive. Methods: We evaluated the effects of suspended particulate matter (SPM) on cardiovascular disease mortality, focusing on types of stroke, from March 2005 to December 2010, in five selected prefectures in western Japan. A multicity time-series analysis was used, and Asian dust was adjusted in the models. Results: Even after adjusting for Asian dust, the same-day SPM was positively associated with several types of stroke mortality. Following a 10-μg/m3 increase in SPM, rate ratios were 1.014 (90% confidence interval [CI]: 1.002 to 1.026) for stroke, 1.030 (90% CI: 1.004 to 1.056) for intracerebral hemorrhage, and 1.016 (90% CI: 1.003 to 1.030) for ischemic stroke mortality. Conclusions: Short-term exposure to outdoor air pollution may increase the risks of hemorrhagic stroke as well as ischemic stroke mortality. Copyright © 2013 by American College of Occupational and Environmental Medicine.
Zhang X.,Osaka University |
Horibata K.,Osaka University |
Horibata K.,Japan National Institute of Health Sciences |
Saijo M.,Osaka University |
And 9 more authors.
Nature Genetics | Year: 2012
UV-sensitive syndrome (UV SS) is an autosomal recessive disorder characterized by photosensitivity and deficiency in transcription-coupled repair (TCR), a subpathway of nucleotide-excision repair that rapidly removes transcription-blocking DNA damage. Cockayne syndrome is a related disorder with defective TCR and consists of two complementation groups, Cockayne syndrome (CS)-A and CS-B, which are caused by mutations in ERCC8 (CSA) and ERCC6 (CSB), respectively. UV SS comprises three groups, UV SS/CS-A, UV SS/CS-B and UV SS-A, caused by mutations in ERCC8, ERCC6 and an unidentified gene, respectively. Here, we report the cloning of the gene mutated in UV SS-A by microcell-mediated chromosome transfer. The predicted human gene UVSSA (formerly known as KIAA1530) corrects defective TCR in UV SS-A cells. We identify three nonsense and frameshift UVSSA mutations in individuals with UV SS-A, indicating that UVSSA is the causative gene for this syndrome. The UVSSA protein forms a complex with USP7 (ref. 8), stabilizes ERCC6 and restores the hypophosphorylated form of RNA polymerase II after UV irradiation. © 2012 Nature America, Inc. All rights reserved.
Wu Y.,Yamaguchi University |
Yamamoto H.,Hiroshima University
Periodica Polytechnica: Civil Engineering | Year: 2015
Particle crushing dominates the deformation behaviour of granular materials under significantly high compressive and shear stress. A proposed constitutive model has been verified to predict crushing behaviour of granular materials with different crushability and adopted one kind of reference crushing stress. It is noted that no positive dilatancy of granular material in triaxial test occurs once the confining pressure exceeds a certain stress level. That stress is defined as the reference crushing stress. This study presents a parametric study on the reference crushing stress in the constitutive model and examines its variation for different distributed ranges of grain size gradation and relative densities. Predicted results demonstrate that the peak stress ratio increases and contractive behaviour becomes less obvious with a larger reference crushing stress. Reference crushing stress increases with a wider grain size gradation and larger relative density for the same granular material. A linear relationship between the reference crushing stress and single particle strength has been obtained from the numerical and experimental results. The reference crushing stress can be recognized as one effective index to evaluate the strength of granular material in triaxial tests. © 2015, Technical University of Budapest. All rights reserved.
Otsu H.,Hirosaki University |
Moriyama M.,Hiroshima University
Japan Journal of Nursing Science | Year: 2011
Aim: The occurrence rate of chronic heart failure (CHF) in Japan is estimated to be 50000 per one million persons. It is important for the Japanese medical financial system to institute a program of disease management in order to prevent the deterioration of persons with CHF. However, there are still few studies on the disease management of CHF in Japan. Therefore, the purpose of this study was to provide an educational self-management program to Japanese outpatients with CHF in order to improve their clinical outcomes. Methods: A randomized, controlled trial with 102 outpatients with CHF was conducted. There were 50 participants in the intervention group and 52 participants in the control group. The control group received medical treatment and standard care. In addition to this, the intervention group also received an educational program for 6months. The program consisted of six nurse-directed sessions that were provided to each outpatient once per month in a clinical setting for a total of 6months. A follow-up session was conducted each month for 6months. The data collection was carried out at the start of the program and at 3, 6, 9, and 12months. Results: Significant differences could be observed in the primary and secondary outcomes and in the process indicators between the two groups after the program began. In other words, all the indicators improved for the intervention group, compared to the control group. Therefore, this program was considered to be effective. Conclusion: Further long-term care is necessary for outpatients with CHF in order to prevent their deterioration and to maintain their health status, even though this 6month program did provide them with proper knowledge regarding self-care for CHF and affected their therapy results. © 2010 The Authors. Japan Journal of Nursing Science © 2010 Japan Academy of Nursing Science.
Zenitani S.,NASA |
Miyoshi T.,Hiroshima University
Physics of Plasmas | Year: 2011
Plasmoid structures in fast reconnection in low-beta plasmas are investigated by two-dimensional magnetohydrodynamic simulations. A high-resolution shock-capturing code enables us to explore a variety of shock structures: vertical slow shocks behind the plasmoid, another slow shock in the outer-region, and the shock-reflection in the front side. The Kelvin-Helmholtz-like turbulence is also found inside the plasmoid. It is concluded that these shocks are rigorous features in reconnection in low-beta plasmas, where the reconnection jet speed or the upstream Alfv́n speed exceeds the sound speed. © 2011 American Institute of Physics.
Maruyama H.,Hiroshima University
Clinical Neurology | Year: 2012
Amyotrophic lateral sclerosis (ALS) is a devastating disorder characterized by degeneration of motor neurons of the primary motor cortex, brainstem and spinal cord. ALS patients die within 3 to 5 years without respiratory support. Detecting the causing gene is necessary to elucidate ALS. We identified mutations of optineurin (OPTN) in ALS. We found three types of mutation of OPTN: a homozygous deletion of exon 5, a homozygous Q398X nonsense mutation and a heterozygous E478G missense mutation within its ubiquitin-binding domain. Cell transfection experiments showed that the nonsense and missense mutations of OPTN aboHshed the inhibition of activation of nuclear factor kappa B. The missense mutation revealed a cytoplasmic distribution different from that of the wild type. A case with the E478G mutation showed OPTN-immunoreactive cytoplasmic retention, and Golgi fragmentation was identified in 70% of the anterior horn cells. TDP-43- or SOD1-positive inclusions of sporadic and SOD1 cases of ALS were also immunolabelled with anti-OPTN antibodies. Furthermore, optineurin is co-localized with fused in sarcoma (FUS) in basophilic inclusions of ALS with FUS mutation and in basophilic inclusion body disease. Our findings suggest that OPTN is involved in the great part of pathogenesis of ALS.
Tawfik A.,Hiroshima University |
Tawfik A.,Cairo University
Indian Journal of Physics | Year: 2011
The in-medium modifications of hadron properties are briefly discussed. We restrict the discussion to the lattice QCD calculations for the hadron masses, screening masses, decay constants and wave functions. We review the progress made so far and describe how to broaden its horizon. © 2011 IACS.
Ota Y.,Hiroshima University
Zootaxa | Year: 2012
A marine biodiversity expedition was carried out from 7 November to 22 November 2009 in Kumejima Island, the Ryukyu Archipelago, southwestern Japan. The dredge and trawl samplings from 10 to 147 m depths yielded five gnathiid species including three new Gnathia species. In this paper, these three new species are described based on male morphologies and three morphotypes of larvae are also described. Copyright © 2012. Magnolia Press.
Iwakura I.,Hiroshima University |
Iwakura I.,Japan Science and Technology Agency |
Iwakura I.,University of Electro - Communications
Physical Chemistry Chemical Physics | Year: 2011
Have you ever hoped to observe transition states? Chemists have long desired to monitor the deformation of molecular structures via transition states to understand the mechanisms of complicated reactions. Detailed knowledge of transition states helps find strategies to develop novel reaction schemes for introducing new functionalities to chemicals. Molecular structural changes via transition states can be observed by real-time vibrational spectroscopy using sub-5 fs laser pulses. In this paper, I report the direct observation of time-dependent frequency shifts of relevant molecular vibrational modes, which allowed for the clear visualization of ultrafast structural changes in molecules during bond breaking and bond reformation steps. Various mechanisms for photochemical reactions were clarified using sub-5 fs laser pulses. Moreover, a non-thermal vibrational excitation method for efficiently driving chemical reactions in the electronic ground state in solution with the use of broadband visible sub-5 fs laser pulses has been developed. The respective chemical reaction processes were directly observed, including transition states during not only "photochemical" but also "thermal" reactions. Time-resolved spectroscopy with a time resolution of a few femtoseconds enables observation of real-time vibrational amplitudes of complicated molecules and opens up new ways for clarifying reaction mechanisms and developing new chemical transformations. © the Owner Societies. 2011.
Managi S.,Yokohama National University |
Kaneko S.,Hiroshima University
Environmental Economics and Policy Studies | Year: 2014
Environmental problems are threatening China’s sustainable future. China began the implementation of several environmental policies in the late 1970s and the stringency of these regulations is increasing. We utilize province-level data over the period 1987–2001 to measure various components of productivity within a joint production model that considers both market and environmental outputs. We estimate both Malmquist and Luenberger productivity indices and find that environmental management in China is deteriorating, while the productivity level of joint production is relatively constant. © 2006, Springer Japan.
Ubuka T.,Waseda University |
Inoue K.,Waseda University |
Fukuda Y.,Waseda University |
Mizuno T.,Waseda University |
And 3 more authors.
Endocrinology | Year: 2012
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that inhibits gonadotropin secretion in birds and mammals. To further understand its physiological roles in mammalian reproduction, we identified its precursor cDNA and endogenous mature peptides in the Siberian hamster brain. The Siberian hamster GnIH precursor cDNA encoded two RFamide-related peptide (RFRP) sequences. SPAPANKVPHSAANLPLRF-NH 2 (Siberian hamster RFRP-1) and TLSRVPSLPQRFNH 2 (Siberian hamster RFRP-3) were confirmed as mature endogenous peptides by mass spectrometry from brain samples purified by immunoaffinity chromatography. GnIH mRNA expression was higher in long days (LD) compared with short days (SD). GnIH mRNA was also highly expressed in SD plus pinealectomized animals, whereas expression was suppressed by melatonin, a nocturnal pineal hormone, administration. GnIH-immunoreactive (-ir) neurons were localized to the dorsomedial region of the hypothalamus, and GnIH-ir fibers projected to hypothalamic and limbic structures. The density of GnIH-ir perikarya and fibers were higher in LD and SD plus pinealectomized hamsters than in LD plus melatonin or SD animals. The percentage of GnRH neurons receiving close appositions from GnIH-ir fiber terminals was also higher in LD than SD, and GnIH receptor was expressed in GnRH-ir neurons. Finally, central administration of hamster RFRP-1 or RFRP-3 inhibited LH release 5 and 30 min after administration in LD. In sharp contrast, both peptides stimulated LH release 30 min after administration in SD. These results suggest that GnIH peptides fine tune LH levels via its receptor expressed in GnRH-ir neurons in an opposing fashion across the seasons in Siberian hamsters. Copyright © 2012 by The Endocrine Society.
Ohsaki M.,Hiroshima University |
Nakajima T.,Kyoto University
Journal of Constructional Steel Research | Year: 2012
An optimization method is presented for design of an eccentrically braced frame (EBF), which is used as a passive control device for seismic design of building frames. The link member between the connections of beams and braces of EBF is reinforced with stiffeners in order to improve its stiffness and plastic deformation capacity. We present a method for optimizing the locations and thicknesses of the stiffeners of the link member. The optimal solutions are found using a heuristic approach called tabu search. The objective function is the plastic dissipated energy before failure. The deformation of the link member under static cyclic loads is simulated using a finite element analysis software package. It is demonstrated in the numerical examples that the dissipated energy can be increased through optimization within small number of analyses. © 2012 Elsevier Ltd. All rights reserved.
Nakahara R.,Osaka University |
Nakahara R.,Osaka Institute of Technology |
Uno M.,Osaka University |
Uno M.,Osaka Institute of Technology |
And 3 more authors.
Advanced Materials | Year: 2012
Flexible three-dimensional organic field-effect transistors with high performance are developed utilizing simple imprint technology. Owing to the multiplied vertical channels with short channel length of 0.9 μm, the devices show high output current density and fast dynamic response within 140 ns, which corresponds to as high as 7 MHz. The present fabrication process using imprint technique has advantages in low-cost, a high throughput, and easy processes. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ikeda A.,Hiroshima University
Chemical Record | Year: 2016
An effective exchange method is described whereby liposomal drug carriers of hydrophobic guest biomolecules are used to incorporate the guests into lipid membranes. The exchange method transfers the guest molecule from a cyclodextrin cavity to a liposome in water. Lipid-membrane-incorporated fullerenes (LMICx: x = 60 or 70) prepared by the exchange method have much higher liposomal stability and fullerene water solubility than those prepared by conventional methods. The LMIC60 have high photodynamic activities with respect to human cancer cells under 350-500 nm excitation. Furthermore, the LMIC60 bilayers, containing light-harvesting antenna molecules in addition to the C60, showed improved activities at the optimal wavelength for photodynamic therapy. © 2015 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Matsumoto S.,Osaka University |
Fumoto K.,University Utrecht |
Okamoto T.,Hiroshima University |
Kaibuchi K.,Nagoya University |
Kikuchi A.,Osaka University
EMBO Journal | Year: 2010
Wnt5a is a representative ligand that activates the Wnt/Β-catenin- independent pathway, resulting in the regulation of cell adhesion, migration, and polarity, but its molecular mechanism is poorly understood. This report shows that Dishevelled (Dvl) binds to adenomatous polyposis coli (APC) gene product, and this binding is enhanced by Wnt5a. Dvl was involved in the stabilization of the plus end dynamics of microtubules as well as APC. Frizzled2 (Fz2) was present with Wnt5a at the leading edge of migrating cells and formed a complex with APC through Dvl. Fz2 also interacted with integrins at the leading edge, and Dvl and APC associated with and activated focal adhesion kinase and paxillin. The binding of APC to Dvl enhanced the localization of paxillin to the leading edge and was involved in Wnt5a-dependent focal adhesion turnover. Furthermore, this new Wnt5a signalling pathway was important for the epithelial morphogenesis in the three-dimensional culture. These results suggest that the functional and physical interaction of Dvl and APC is involved in Wnt5a/Fz2-dependent focal adhesion dynamics during cell migration and epithelial morphogenesis. © 2010 European Molecular Biology Organization | All Rights Reserved.
Nakano M.,RIKEN |
Osaka I.,RIKEN |
Takimiya K.,RIKEN |
Takimiya K.,Hiroshima University |
Koganezawa T.,Japan Synchrotron Radiation Research Institute
Journal of Materials Chemistry C | Year: 2014
Dibenzo[a,e]pentalene (DBP), a ladder-type fused-ring system with 16π anti-aromatic nature, is integrated into conjugated polymers with oligothiophene building blocks to examine the potential of DBP as a new building block for semiconducting polymers. Depending on the incorporation manner of the DBP unit in the polymer backbone, via the 5,10- or 2,7-positions, the polymers show distinct colours, reflecting the different electronic structures, though the HOMO and LUMO energy levels estimated from cyclic voltammograms are almost the same. Interestingly, the impact of the incorporation manner was observed in the characteristics of their field-effect transistors (FETs). For PDTDBP2Ts, in which the DBP units are integrated into the polymer backbone via the 5,10-positions, the DBP units behave like a "dibenzo-annulated 1,3-butadiene" moiety, and their FET characteristics are strongly affected by orientational ordering and crystallinity, similar to ordinary "donor-only" polymers such as P3HT. On the other hand, iPDTDBP2Ts, in which the whole 16π DBP unit is integrated into the polymer backbone via the 2,7-positions, behave like a certain kind of donor-acceptor polymers, and the FET characteristics are independent of orientational order: the field-effect mobilities are higher than 0.1 cm2 V-1 s-1 regardless of the polymer orientation in the thin film. From these results, we can recognize the 16π anti-aromatic DBP unit as a useful building block with transmutable nature for the development of new conjugated polymers. © 2014 The Royal Society of Chemistry.
Kobayashi H.,Tokyo University of Agriculture |
Sakurai T.,Tokyo University of Agriculture |
Imai M.,Tokyo University of Agriculture |
Takahashi N.,Tokyo University of Agriculture |
And 8 more authors.
PLoS Genetics | Year: 2012
Genome-wide dynamic changes in DNA methylation are indispensable for germline development and genomic imprinting in mammals. Here, we report single-base resolution DNA methylome and transcriptome maps of mouse germ cells, generated using whole-genome shotgun bisulfite sequencing and cDNA sequencing (mRNA-seq). Oocyte genomes showed a significant positive correlation between mRNA transcript levels and methylation of the transcribed region. Sperm genomes had nearly complete coverage of methylation, except in the CpG-rich regions, and showed a significant negative correlation between gene expression and promoter methylation. Thus, these methylome maps revealed that oocytes and sperms are widely different in the extent and distribution of DNA methylation. Furthermore, a comparison of oocyte and sperm methylomes identified more than 1,600 CpG islands differentially methylated in oocytes and sperm (germline differentially methylated regions, gDMRs), in addition to the known imprinting control regions (ICRs). About half of these differentially methylated DNA sequences appear to be at least partially resistant to the global DNA demethylation that occurs during preimplantation development. In the absence of Dnmt3L, neither methylation of most oocyte-methylated gDMRs nor intragenic methylation was observed. There was also genome-wide hypomethylation, and partial methylation at particular retrotransposons, while maintaining global gene expression, in oocytes. Along with the identification of the many Dnmt3L-dependent gDMRs at intragenic regions, the present results suggest that oocyte methylation can be divided into 2 types: Dnmt3L-dependent methylation, which is required for maternal methylation imprinting, and Dnmt3L-independent methylation, which might be essential for endogenous retroviral DNA silencing. The present data provide entirely new perspectives on the evaluation of epigenetic markers in germline cells. © 2012 Kobayashi et al.
Hidaka H.,Hiroshima University |
Yoneda S.,National Museum of Nature and Science
Geochimica et Cosmochimica Acta | Year: 2011
Barium isotopic compositions of chemical leachates from six carbonaceous chondrites, Orgueil (CI), Mighei (CM2), Murray (CM2), Efremovka (CV3), Kainsaz (CO3), and Karoonda (CK4), were determined using thermal ionization mass spectrometry in order to assess the chemical evolution in the early solar system. The Ba isotopic data from most of the leachates show variable 135Ba excesses correlated with 137Ba excesses, suggesting the presence and heterogeneity of additional nucleosynthetic components for s- and r-processes in the solar system. The isotopic deviations observed in this study were generally small (-1<ε<+1) except in the case of the acid residues of CI and CM meteorites. Large deviations of 135Ba (ε=-13.5 to -5.0) and 137Ba (ε=-6.2∼-1.2) observed in the acid residues from one CI and two CM meteorites show significant evidence for the enrichment of s-process isotopes derived from presolar grains. Two models were proposed to estimate the 135Cs isotopic abundances by subtraction of the s- and r-isotopic components from the total Ba isotopic abundances in the three CM meteorites, Mighei, Murchison (measured in a previous study), and Murray. The data points show individual linear trends between 135Cs/136Ba ratios and 135Ba isotopic deviations for the three samples. Considering the different trends observed in the three CM meteorites, the Ba isotopic composition of the CM meteorite parent body was heterogeneous at its formation. Chronological information is unclear in the data for Murchison and Murray because of large analytical uncertainties imposed by error propagation. Only the Mighei meteorite data indicate the possible existence of presently extinct 135Cs (135Cs/133Cs=(2.7±1.6)×10-4) in the early solar system. Another explanation of the data for the three CM meteorite is mixing of at least three components with different Ba isotopic compositions, although this is model-dependent. © 2011 Elsevier Ltd.
Etiope G.,Italian National Institute of Geophysics and Volcanology |
Nakada R.,Hiroshima University |
Tanaka K.,Yamaguchi University |
Yoshida N.,Tokyo Institute of Technology
Applied Geochemistry | Year: 2011
Methane and CO2 emissions from the two most active mud volcanoes in central Japan, Murono and Kamou (Tokamachi City, Niigata Basin), were measured in from both craters or vents (macro-seepage) and invisible exhalation from the soil (mini- and microseepage). Molecular and isotopic compositions of the released gases were also determined. Gas is thermogenic (δ13CCH4 from -32.9‰ to -36.2‰), likely associated with oil, and enrichments of 13C in CO2 (δ13CCO2 up to +28.3‰) and propane (δ13CC3H8 up to -8.6‰) suggest subsurface petroleum biodegradation. Gas source and post-genetic alteration processes did not change from 2004 to 2010. Methane flux ranged within the orders of magnitude of 101-104gm-2d-1 in macro-seeps, and up to 446gm-2d-1 from diffuse seepage. Positive CH4 fluxes from dry soil were widespread throughout the investigated areas. Total CH4 emission from Murono and Kamou were estimated to be at least 20 and 3.7tona-1, respectively, of which more than half was from invisible seepage surrounding the mud volcano vents. At the macro-seeps, CO2 fluxes were directly proportional to CH4 fluxes, and the volumetric ratios between CH4 flux and CO2 flux were similar to the compositional CH4/CO2 volume ratio. Macro-seep flux data, in addition to those of other 13 mud volcanoes, supported the hypothesis that molecular fractionation (increase of the "Bernard ratio" C1/(C2+C3)) is inversely proportional to gas migration fluxes. The CH4 "emission factor" (total measured output divided by investigated seepage area) was similar to that derived in other mud volcanoes of the same size and activity. The updated global "emission-factor" data-set, now including 27 mud volcanoes from different countries, suggests that previous estimates of global CH4 emission from mud volcanoes may be significantly underestimated. © 2010 Elsevier Ltd.
De Paola N.,Durham University |
Hirose T.,Japan Agency for Marine - Earth Science and Technology |
Mitchell T.,Ruhr University Bochum |
Di Toro G.,Italian National Institute of Geophysics and Volcanology |
And 3 more authors.
Geology | Year: 2011
Experiments performed on dolomite or Mg-calcite gouges at seismic slip rates (v > 1 m/s) and displacements (d > 1 m) show that the frictional coefficient μ decays exponentially from peak values (mp ≈ 0.8, in the Byerlee's range), to extremely low steady-state values (μss ≈ 0.1), attained over a weakening distance Dw. Microstructural observations show that discontinuous patches of nanoparticles of dolomite and its decomposition products (periclase and lime or portlandite) were produced in the slip zone during the transient stage (d < Dw). These observations, integrated with CO2 emissions data recorded during the experiments, suggest that particle interaction in the slip zone produces flash temperatures that are large enough to activate chemical and physical processes, e.g., decarbonation reactions (T = 550 °C). During steady state (d ≥ Dw), shear strength is very low and not dependent upon normal stresses, suggesting that pressurized fluids (CO2) may have been temporarily trapped within the slip zone. At this stage a continuous layer of nanoparticles is developed in the slip zone. For d >> Dw, a slight but abrupt increase in shear strength is observed and interpreted as due to fluids escaping the slip zone. At this stage, dynamic weakening appears to be controlled by velocity dependent properties of nanoparticles developed in the slip zone. Experimentally derived seismic source parameter Wb (i.e., breakdown work, the energy that controls the dynamics of a propagating fracture) (1) matches Wb values obtained from seismological data of the A.D. 1997 M6 Colfiorito (Italy) earthquakes, which nucleated in the same type of rocks tested in this study, and (2) suggests similar earthquake-scaling relationships, as inferred from existing seismological data sets. We conclude that dynamic weakening of experimental faults is controlled by multiple slip weakening mechanisms, which are activated or inhibited by physicochemical reactions in the slip zone. © 2011 Geological Society of America.
Kajiyama H.,Hiroshima University
49th Annual SID Symposium, Seminar, and Exhibition 2011, Display Week 2011 | Year: 2011
The loss of wall voltage during the addressing waiting time t w has been investigated, and is found to correspond to an effective exoemission current that is inversely related to the time, i.e. Iexo ∼ 1/t w. This relation is approximately valid over 3 decades from 20 usec to 16.7 msec.. The wall voltage loss for Sc 3+ doped MgO is about three times larger than that of non-doped MgO.
Hidaka H.,Hiroshima University |
Yoneda S.,National Museum of Nature and Science
Geochimica et Cosmochimica Acta | Year: 2011
The Sm and Gd isotopic compositions of silicates from six mesosiderites (Dalgaranga, Estherville, Morristown, Northwest Africa (NWA) 1242, NWA 2932, and Vaca Muerta) and one iron meteorite (Udei Station) were determined to elucidate the cosmic-ray exposure records. All seven samples showed significant 150Sm/149Sm and 158Gd/157Gd isotopic shifts from neutron capture reactions corresponding to neutron fluences of (1.3-21.8)×1015ncm-2. In particular, Vaca Muerta showed a significantly higher neutron fluences than the other six samples. The parameter for the degree of neutron thermalization (εSm/εGd) also showed a significant difference between Vaca Muerta (0.76) and the other samples (0.93-1.20). These results suggest a two-stage irradiation of the Vaca Muerta silicates in the parent body (>50Ma) before formation of the mesosiderite and during its transit to Earth (138Ma). This is consistent with the 81Kr-Kr cosmic-ray exposure age data of a Vaca Muerta pebble from a previous noble gas isotopic study. © 2011 Elsevier Ltd.
Toda A.,Hiroshima University
Journal of Thermal Analysis and Calorimetry | Year: 2016
Crystal melting behavior of indium and isotactic polypropylene has been examined by differential scanning calorimetry of heat flux type in terms of the heating rate, β, dependence. The melting shows the dependence characterized by a power, z, of the shift in peak temperature in proportion to β z. The power, z, differentiates the melting with and without superheating. For polymer crystal melting, intrinsic nature of the broad melting region with a fractional power, z ≤ 1/2, due to superheating of melting kinetics has been reconfirmed experimentally. On the other hand, the crystal melting of indium, which is supposed to proceed with negligible superheating, showed the shift in peak temperature with the power in the range of 1/2 ≤ z ≤ 1, depending on sample mass, which is due to instrumental thermal lag predicted by the Mraw's model consisting of lumped elements. The β dependence is influenced by the thermal lag determined by the thermal contact resistance between the sample pan and the stage, the effect of which has been examined in terms of the dependence on sample mass and the application of silicone grease between the sample pan and the stage. The influence of two different types of the definition of heat flow has also been examined; the simplified one without the time derivative of temperature difference showed an apparent shift in peak temperature at faster scan rates in a similar way as that of thermal lag. © 2015 Akadémiai Kiadó, Budapest, Hungary.
Kong F.,Nanjing University |
Yin H.,Nanjing University |
Nakagoshi N.,Hiroshima University |
Zong Y.,Nanjing University
Landscape and Urban Planning | Year: 2010
Urban areas can contain rich flora that contribute significantly to biodiversity, but loss and isolation of habitats due to urban sprawl threaten biodiversity and warrant limits on development. The connectivity provided by urban green spaces offers habitats and corridors that help conserve biodiversity. Researchers and planners have begun using landscape ecology principles to develop green space networks and increase connectivity to preserve and restore biodiversity. In this paper, potential corridors were identified in Jinan City, China, using the least-cost path method, and green space networks were developed and improved based on graph theory and the gravity model. Spatial analysis revealed that the proposed plan decreased fragmentation and increased connectivity. Plaza and roadside green spaces were the main types of green space that increased, but they only weakly improved networks and biodiversity. Identifying potential corridors using least-cost path analysis made the results better approximate the real landscape by including impedance along links. The potential networks revealed problems in the current greening plan. The green space network developed based on graph theory and the gravity model simplified and systematized the complex landscape, helping to identify the significance of each green space and guiding urban planning for biodiversity conservation. © 2009 Elsevier B.V. All rights reserved.
Kitamura K.,Hiroshima University |
Nakase M.,Kyushu University |
Tohda H.,Asahi Glass Co. |
Takegawa K.,Kyushu University
Eukaryotic Cell | Year: 2012
Uptake of extracellular oligopeptides in yeast is mediated mainly by specific transporters of the peptide transporter (PTR) and oligopeptide transporter (OPT) families. Here, we investigated the role of potential peptide transporters in the yeast Schizosaccharomyces pombe. Utilization of naturally occurring dipeptides required only Ptr2/SPBC13A2.04c and none of the other 3 OPT proteins (Isp4, Pgt1, and Opt3), whereas only Isp4 was indispensable for tetrapeptide utilization. Both Ptr2 and Isp4 localized to the cell surface, but under rich nutrient conditions Isp4 localized in the Golgi apparatus through the function of the ubiquitin ligase Pub1. Furthermore, the ubiquitin ligase Ubr11 played a significant role in oligopeptide utilization. The mRNA levels of both the ptr2 and isp4 genes were significantly reduced in ubr11Δ cells, and the dipeptide utilization defect in the ubr11Δ mutant was rescued by the forced expression of Ptr2. Consistent with its role in transcriptional regulation of peptide transporter genes, the Ubr11 protein was accumulated in the nucleus. Unlike the situation in Saccharomyces cerevisiae, the oligopeptide utilization defect in the S. pombe ubr11Δ mutant was not rescued by inactivation of the Tup11/12 transcriptional corepressors, suggesting that the requirement for the Ubr ubiquitin ligase in the upregulation of peptide transporter mRNA levels is conserved in both yeasts; however, the actual mechanism underlying the control appears to be different. We also found that the peptidomimetic proteasome inhibitor MG132 was still operative in a strain lacking all known PTR and OPT peptide transporters. Therefore, irrespective of its peptide-like structure, MG132 is carried into cells independently of the representative peptide transporters. © 2012, American Society for Microbiology.
Yamada T.,Hiroshima University
Frontiers in Microbiology | Year: 2013
Some phages from genus Inovirus use host or bacteriophage-encoded site-specific integrases or recombinases establish a prophage state. During integration or excision, a superinfective form can be produced. The three states (free, prophage, and superinfective) of such phages exert different effects on host bacterial phenotypes. In Ralstonia solanacearum, the causative agent of bacterial wilt disease of crops, the bacterial virulence can be positively or negatively affected by filamentous phages, depending on their state. The presence or absence of a repressor gene in the phage genome may be responsible for the host phenotypic differences (virulent or avirulent) caused by phage infection. This strategy of virulence control may be widespread among filamentous phages that infect pathogenic bacteria of plants. © 2013 Yamada.
Ota Y.,Hiroshima University
Zootaxa | Year: 2013
Five gnathiid species from Japan are redescribed based on14 holotypes, their paratypes, topotypes, and new materials. Ob-servations of these specimens revealed that Caecognathia kikuchii (Nunomura, 1992) should be transferred to genus Ela-phognathia and Caecognathia nasuta (Nunomura, 1992) to genus Gnathia. Furthermore, Caecognathia amakusaensis Nunomura, 1992, C. saikaiensis Nunomura, 1992, Gnathia azumai Nunomura, 2012a, G. quadricephala Nunomura, 2012a, and G. recticornata Nunomura, 2012a are considered to be junior synonyms of E. kikuchii. Gnathia hirayamai Nunomura, 1992, G. nagasakiensis Nunomura, 2012a, G. shijikiensis Nunomura, 2012a, and G. brevicephala Nunomura, 2012a are considered to be junior synonyms of G. nasuta. Moreover, Gnathia sanrikuensis Nunomura, 1998 and G. mut-suensis Nunomura, 2004 are redescribed. Gnathia bungoensis Nunomura, 1982 is not completely redescribed because the key characteristics were lacking. The geographical records of these species are provided. Copyright © 2013 Magnolia Press.
Fujii H.,Tohoku University |
Managi S.,Tohoku University |
Kaneko S.,Hiroshima University
Journal of Cleaner Production | Year: 2013
This study analyzes the management of air pollutant substance in Chinese industrial sectors from 1998 to 2009. Decomposition analysis applying the logarithmic mean divisia index is used to analyze changes in emissions of air pollutants with a focus on the following five factors: coal pollution intensity (CPI), end-of-pipe treatment (EOP), the energy mix (EM), productive efficiency change (EFF), and production scale changes (PSC). Three pollutants are the main focus of this study: sulfur dioxide (SO2), dust, and soot. The novelty of this paper is focusing on the impact of the elimination policy on air pollution management in China by type of industry using the scale merit effect for pollution abatement technology change. First, the increase in SO2 emissions from Chinese industrial sectors because of the increase in the production scale is demonstrated. However, the EOP equipment that induced this change and improvements in energy efficiency has prevented an increase in SO2 emissions that is commensurate with the increase in production. Second, soot emissions were successfully reduced and controlled in all industries except the steel industry between 1998 and 2009, even though the production scale expanded for these industries. This reduction was achieved through improvements in EOP technology and in energy efficiency. Dust emissions decreased by nearly 65% between 1998 and 2009 in the Chinese industrial sectors. This successful reduction in emissions was achieved by implementing EOP technology and pollution prevention activities during the production processes, especially in the cement industry. Finally, pollution prevention in the cement industry is shown to result from production technology development rather than scale merit. © 2013 Elsevier Ltd. All rights reserved.
Mori K.,Japan National Institute of Advanced Industrial Science and Technology |
Iwanaga M.,Hiroshima University
International Journal of Psychophysiology | Year: 2014
In the study of emotion and autonomic nervous system functioning, resting physiological arousal is usually considered a negative characteristic. The present study examined the relationship between resting physiological arousal and positive emotional experience linked to psychophysiological arousal. We assessed resting physiological arousal using markers as high skin conductance level and low respiratory sinus arrhythmia, measured just before participants listened to their favorite music. Participants reported the sensation of chills (goose bumps, shivers) by pressing a mouse button while listening. The results indicated that individuals with resting physiological arousal frequently experience music-induced chills, which evoked unambiguous pleasurable feelings and an increase in skin conductance response. The current results, and the previously demonstrated relationship between resting physiological arousal and negative emotionality linked to psychophysiological arousal (e.g., anxiety, panic), suggest that resting physiological arousal may reflect sensitivity to psychophysiological arousal with both intense positive and negative emotions. © 2014 Elsevier B.V.
Nagasawa K.,Hiroshima University
Journal of Natural History | Year: 2015
This paper reviews aspects of the biology of copepods infecting marine fish commercially cultured at fish farms or held as broodstock at governmental hatcheries in Japan. In total, 20 species of parasitic copepods have been reported from these fish: they are mostly caligids (12 spp.), followed by lernaeopodids (4 spp.), pennellid (1 sp.), chondracanthid (1 sp.), taeniacanthid (1 sp.), and unidentified species (1 sp.). The identified copepods are: Caligus fugu, C. lagocephalus, C. lalandei, C. latigenitalis, C. longipedis, C. macarovi, C. orientalis, C. sclerotinosus, C. spinosus, Lepeophtheirus longiventralis, L. paralichthydis, L. salmonis (Caligidae); Alella macrotrachelus, Clavella parva, Parabrachiella hugu, P. seriolae (Lernaeopodidae); Peniculus minuticaudae (Pennellidae); Acanthochondria priacanthi (Chondracanthidae); and Biacanthus pleuronichthydis (Taeniacanthidae). The fish recorded as hosts include carangids (4 spp.), sparids (2 spp.), monacanthids (2 spp.), salmonids (2 spp.), scombrid (1 sp.), tetraodontid (1 sp.), pleuronectid (1 sp.), paralichthyid (1 sp.), and trichodontid (1 sp.). Only five species (C. orientalis, L. longiventralis, L. salmonis, C. parva and A. priacanthi) parasitize farmed fish in subarctic waters, while all other species (15 spp.) infect farmed fish in temperate waters. No information is yet available on copepods from fish farmed in subtropical waters. Three species of Caligus (C. fugu, C. sclerotinosus and C. longipedis) are serious pests in aquaculture of Japanese pufferfish (Takifugu rubripes), red seabream (Pagrus major), and striped jaw (Pseudocaranx dentex), respectively. Due to its one-host life cycle that is unique among pennellids, P. minuticaudae is considered as a potentially serious pest with further development of aquaculture of its filefish hosts, threadsail filefish (Stephanolepis cirrhifer) and black scraper (Thamnaconus modestus). Infection of farmed salmonids by L. salmonis is not a serious problem in Japan. © 2015 Taylor & Francis.
Lee H.S.,Saitama University |
Kaneko A.,Hiroshima University
Atmosphere - Ocean | Year: 2015
Future sea-level rise (SLR) in and around the Seto Inland Sea (SIS), Japan, is estimated in 2050 and 2100 using ensemble empirical mode decomposition (EEMD) and long-term sea-level records. Ensemble empirical mode decomposition, an adaptive data analysis method, can separate sea-level records into intrinsic mode functions (IMFs) from high to low frequencies and a residual. The residual is considered a non-linear trend in the sea-level records. The mean SLR trend at Tokuyama in the SIS from EEMD is 3.00 mm y-1 from 1993 to 2010, which is slightly lower than the recent altimetry-based global rate of 3.3 ± 0.4 mm y-1 during the same period. Uncertainty in SLR is estimated by considering interdecadal variations in the sea levels. The resulting SLR in 2050 and 2100 for Tokuyama is 0.19 ± 0.06 m and 0.56 ± 0.18 m, respectively. The stations along the coast of the Pacific Ocean display a greater and more rapid SLR in 2100 compared with other stations in the SIS. The SLR is caused not only by mass and volume changes in the sea water but also by other factors, such as local subsidence, tectonic motion, and river discharge. The non-linear trend of SLR, which is the residual from EEMD, is interpreted as the sum of the local factors that contribute to the sea-level budget. © 2015 Taylor & Francis.
Kojima Y.,Hiroshima University
Monthly Notices of the Royal Astronomical Society | Year: 2015
We examine energy conversion from accreting pair plasma to outgoing Poynting flux by black hole rotation. Our approach is based on a two-fluid model consisting of collisionless pair plasma. The electric potential is not constant along magnetic field lines, unlike an ideal magnetohydrodynamics approximation. We show how and where longitudinal electric fields and toroidal magnetic fields are generated by the rotation, whereas they vanish everywhere for radial flow in a split-monopole magnetic field in a Schwarzschild black hole. Outgoing electromagnetic power in a steady state is calculated by applying the WKB method to the perturbation equations for a small spin parameter. In our model, the luminosity has a peak in the vicinity of the black hole, but is damped towards the event horizon and infinity. The power at the peak is of the same order as that in the Blandford-Znajek process, although the physical mechanism is different. © 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.
Higashi Y.,Hiroshima University
Nihon rinsho. Japanese journal of clinical medicine | Year: 2012
Nitric oxide (NO) released from endothelial cell plays an important role in the regulation of vascular tone, the inhibition of platelet aggregation, and the suppression of smooth muscle cell proliferation. Activation of renin-angiotensin-aldosterone system(RAAS) plays an important role in the pathogenesis, development, and maintenance of atherosclerosis through an impairment of endothelial function. Angiotensin II stimulates the production of reactive oxygen species by the activation of NADPH oxidase and increases Rho-associated kinase activity that decreases the stability of endothelial nitric oxide synthase (eNOS) mRNA and phosphorylation of eNOS, leading to inactivation of NO bioavailability. An imbalance of reduced production of NO or increased production of reactive oxygen species may promote endothelial cell dysfunction through angiotensin II-induced various signal transduction cascades.
Seno H.,Hiroshima University
Journal of Biological Dynamics | Year: 2010
We analyse a general time-discrete mathematical model of host-parasite population dynamics with harvesting, in which the host can be regarded as a pest. We harvest a portion of the host population at a moment in each year. Our model involves the density effect on the host population. We investigate the condition in which the harvesting of the host results in a paradoxical increase of its equilibrium population size. Our results imply that for a family of pest-enemy systems, the paradox of pest control could be caused essentially by the interspecific relationship and the intraspecific density effect. © 2010 Taylor & Francis.
Ikehata M.,Hiroshima University
Inverse Problems | Year: 2013
This paper is concerned with an inverse obstacle problem which employs the dynamical scattering data of an acoustic wave over a finite time interval. The unknown obstacle is assumed to be a sound-soft one. The governing equation of the wave is given by the classical wave equation. The wave is generated by the initial data localized outside the obstacle and observed over a finite time interval at a place which is not necessary the same as the support of the initial data. The observed data are the so-called bistatic data. In this paper, an enclosure method which employs the bistatic data and is based on two main analytical formulae is developed. The first one enables us to extract the maximum spheroid with focal points at the centre of the support of the initial data and that of the observation points whose exterior encloses the unknown obstacle of general shape. The second one, under some technical assumption for the obstacle including convexity as an example, indicates the deviation of the geometry of the boundary of the obstacle and the maximum spheroid at the contact points. Several implications of those two formulae are also given. In particular, a constructive proof of the uniqueness of a spherical obstacle using the bistatic data is given. © 2013 IOP Publishing Ltd.
Haino T.,Hiroshima University
Chemical Record | Year: 2015
Supramolecular polymeric assemblies represent an emerging, promising class of molecular assemblies with enormous versatility compared with their covalent polymeric counterparts. Although a large number of host-guest motifs have been produced over the history of supramolecular chemistry, only a limited number of recognition motifs have been utilized as supramolecular connections in polymeric assemblies. This account describes the molecular recognition of host molecules based on calixarene and bisporphyrin that demonstrate unique guest encapsulations; subsequently, these host-guest motifs are applied to the synthesis of supramolecular polymers that display polymer-like properties in solution and solid states. In addition, new bisresorcinarenes are developed to form supramolecular polymers that are connected via a rim-to-rim hydrogen-bonded dimeric structure, which is composed of two resorcinarene moieties. © 2015 The Chemical Society of Japan and Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim.
Tomaschitz R.,Hiroshima University
Astrophysics and Space Science | Year: 2010
The impact of a cosmic time evolution of the gravitational constant on SN Ia luminosity and AGN/QSO luminosity functions is studied. The gravitational constant scales linearly with the Hubble parameter, its present-day variation being Ġ0/G0 ≈ 1.9 × 10-4 Gyr-1, compatible with current bounds from lunar laser ranging. Distance moduli of Type Ia supernovae are fitted with a cosmic expansion factor derived from temperature variations of planetary paleoclimates, and a luminosity dependence on look-back time proportional to the varying gravitational constant is inferred from the Hubble diagram. A fit is performed to the comoving space density of X-ray-selected active galactic nuclei (AGNs) and optically selected quasars (QSOs) extending to redshifts z≈6. The initial steep increase of the AGN space density is reproduced by a redshift evolution depending solely on the Hubble parameter as scaling variable. The AGN luminosity scales with the Hubble parameter, and the scaling exponents of the luminosity function, composed of two competing power laws with exponential cutoff, are obtained. Based on the AGN luminosity function, flux-limited X-ray source counts are investigated. The counting functions are derived and put to test by fitting cumulative number counts of soft X-ray point sources compiled from ROSAT, XMM-Newton, and Chandra surveys. © Springer Science+Business Media B.V. 2009.
Takahashi T.,Ryukoku University |
Kurita T.,Hiroshima University
IEEE Transactions on Pattern Analysis and Machine Intelligence | Year: 2015
There are two major approaches to content-based image retrieval using local image descriptors. One is descriptor-by-descriptor matching and the other is based on comparison of global image representation that describes the set of local descriptors of each image. In large-scale problems, the latter is preferred due to its smaller memory requirements; however, it tends to be inferior to the former in terms of retrieval accuracy. To achieve both low memory cost and high accuracy, we investigate an asymmetric approach in which the probability distribution of local descriptors is modeled for each individual database image while the local descriptors of a query are used as is. We adopt a mixture model of probabilistic principal component analysis. The model parameters constitute a global image representation to be stored in database. Then the likelihood function is employed to compute a matching score between each database image and a query. We also propose an algorithm to encode our image representation into more compact codes. Experimental results demonstrate that our method can represent each database image in less than several hundred bytes achieving higher retrieval accuracy than the state-of-the-art method using Fisher vectors. © 2014 IEEE.
Tsuchida T.,Hiroshima University
Marine Georesources and Geotechnology | Year: 2016
Using the data of conventional consolidation tests, the linear ln v–ln (Formula presented.) relation (v = 1 + e is a specific volume) was determined in the region of large effective stresses, and was named as high water content compression line (HWCL). A unique relation between normalized ln v−ln (Formula presented.) was obtained for twenty-one clays with narrow band. Based on the normalized HWCL, e–log (Formula presented.) relation of normally consolidated clay with a specified initial water content was proposed. In this model, the beginning part shows a linear e–log (Formula presented.) relation in the range of (Formula presented.) <σ′HWCL and, in the latter part of the range of (Formula presented.) ≥σ′HWCL, e–log (Formula presented.) relation is on the HWCL, where σ′HWCL is the converging pressure to HWCL. It was shown that the empirical Cc–wL relations could be explained using the HWCL based model with the consideration of initial water contents. By using the proposed model, the change of compression properties of marine clay due to soil structure formed in the deposition process was shown schematically, and the effects of soil structure of in situ marine deposits were evaluated, considering the effect of initial water content. 2016 Copyright © Taylor & Francis Group, LLC
Homma K.,Hiroshima University |
Homma K.,Ecole Polytechnique - Palaiseau
European Physical Journal: Special Topics | Year: 2014
We present a novel approach to search for sub-eV neutral bosons coupling to two photons which can be candidates for dark fields in the universe. Similarly to conventional particle colliders, the search aims at detection of resonance states of these dark fields produced by photon-photon scattering, however, the interaction rate is enhanced by the stimulated decay of resonances into two photons under a background coherent laser field. We discuss the future experimental strategy to explore a large mass-coupling parameter space with high-intensity lasers. © 2014 EDP Sciences and Springer.
Kikkawa T.,Hiroshima University
Microelectronic Engineering | Year: 2011
Inter-chip wireless interconnect technologies such as inductive coupling and electromagnetic wave propagation have been developed for future high performance system in package at low cost. Inductive coupling is used for near field transmission whose distance is shorter than 100 μm as local wireless interconnects. Antennas are used for far field transmission between chips whose distance is longer than 1 cm as global wireless interconnects. A single-chip Gaussian monocycle pulse (GMP) transmitter using complementary metal oxide semiconductor (CMOS) technology with an on-chip integrated antenna was developed for inter-chip ultra wideband (UWB) communication. © 2010 Elsevier B.V. All rights reserved.
Kato T.N.,Hiroshima University |
Kato T.N.,Japan National Astronomical Observatory
Astrophysical Journal | Year: 2015
We herein investigate shock formation and particle acceleration processes for both protons and electrons in a quasi-parallel high-Mach-number collisionless shock through a long-term, large-scale, particle-in-cell simulation. We show that both protons and electrons are accelerated in the shock and that these accelerated particles generate large-amplitude Alfvénic waves in the upstream region of the shock. After the upstream waves have grown sufficiently, the local structure of the collisionless shock becomes substantially similar to that of a quasi-perpendicular shock due to the large transverse magnetic field of the waves. A fraction of protons are accelerated in the shock with a power-law-like energy distribution. The rate of proton injection to the acceleration process is approximately constant, and in the injection process, the phase-trapping mechanism for the protons by the upstream waves can play an important role. The dominant acceleration process is a Fermi-like process through repeated shock crossings of the protons. This process is a "fast" process in the sense that the time required for most of the accelerated protons to complete one cycle of the acceleration process is much shorter than the diffusion time. A fraction of the electrons are also accelerated by the same mechanism, and have a power-law-like energy distribution. However, the injection does not enter a steady state during the simulation, which may be related to the intermittent activity of the upstream waves. Upstream of the shock, a fraction of the electrons are pre-accelerated before reaching the shock, which may contribute to steady electron injection at a later time. © 2015. The American Astronomical Society. All rights reserved.
Takumi T.,Hiroshima University |
Takumi T.,Japan Science and Technology Agency
Brain and Development | Year: 2010
Even now fruit of the human genome project is available, we have difficulties to approach neuropsychiatric disorders at the molecular level. Autism is a complex psychiatric illness but has received considerable attention as a developmental brain disorder not only from basic researchers but also from society. Substantial evidence suggests that chromosomal abnormalities contribute to autism risk. The duplication of human chromosome 15q11-13 is known to be the most frequent cytogenetic abnormality in autism. We succeeded to generate mice with a 6.3-Mb-wide interstitial duplication in mouse chromosome 7c that is highly syntenic to human 15q11-13 by using a Cre-loxP-based chromosome-engineering technique. The only paternally duplicated mice display autistic behavioral features such as poor social interaction and stereotypical behavior, and exhibit a developmental abnormality in ultrasonic vocalizations as well as anxiety. The detailed analysis focusing on a non-coding small nucleolar RNA, MBII52, within the duplicated region, revealed that the paternally duplicated mice alter the editing ratio of serotonin (5-HT) 2c receptor pre-mRNA and intracellular calcium responses by a 5-HT2c receptor specific agonist are changed in neurons. This result may explain one of molecular mechanisms of abnormal behaviors in the paternal duplicated mice. The first chromosome-engineered mouse model for human chromosome 15q11-13 duplication fulfills not only face validity of human autistic phenotypes but also construct validity based on human chromosome abnormality. This model will be a founder mouse for forward genetics of autistic disease and an invaluable tool for its therapeutic development. © 2010 Elsevier B.V.
Tomaschitz R.,Hiroshima University
Physica B: Condensed Matter | Year: 2010
Polylogarithmic fugacity expansions of the partition function, the caloric and thermal equations of state, and the specific heat of fermionic power-law distributions are derived in the nearly degenerate low-temperature/high-density quantum regime. The spectral functions of an ultra-relativistic electron plasma are obtained by averaging the tachyonic radiation densities of inertial electrons with Fermi power-laws, whose entropy is shown to be extensive and stable. The averaged radiation densities are put to test by performing tachyonic cascade fits to the γ-ray spectrum of the TeV blazar Markarian 421 in a low and high emission state. Estimates of the thermal electron plasma in this active galactic nucleus are extracted from the spectral fits, such as temperature, number count, and internal energy. The tachyonic cascades reproduce the quiescent as well as a burst spectrum of the blazar obtained with imaging atmospheric Cherenkov detectors. Double-logarithmic plots of the differential tachyon flux exhibit intrinsic spectral curvature, caused by the Boltzmann factor of the electron gas. © 2009 Elsevier B.V. All rights reserved.
Shima K.,Hiroshima University
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference | Year: 2011
This paper proposes the CPG synergy model--a biomimetic rhythm generator model based on central pattern generators (CPGs) and muscle synergy theory to enable evaluation of rhythmic motions with non-stationary characteristics such as human finger tapping movements. The model consists of multiple CPGs to approximate the complex rhythmic movement of humans, and has the potential to allow evaluation of abnormal movements in patients with motor function impairments such as Parkinson's disease (PD). To verify the validity of the proposed model, comparison experiments were conducted using model parameters (i.e., synergies, weight coefficients and time-shift parameters) extracted from finger tapping movements performed by individuals in a healthy subject group and a PD patient group. The results showed that the number of synergies, the second moment of synergy shapes and the coefficient of variation of maximum weight coefficients show significant differences for each subject group, and indicated that the model could be used to evaluate irregular rhythmic movements as well as regular ones.
Nishida K.,Hiroshima University
Applied Physics B: Lasers and Optics | Year: 2010
This paper describes an Ultraviolet-Visible Laser Absorption-Scattering (UV-Vis LAS) imaging technique applied to asymmetric fuel sprays. Continuing from the previous studies, the detailed measurement principle was derived. It is demonstrated that, by means of this technique, cumulative masses and mass distributions of vapor/liquid phases can be quantitatively measured no matter what shape the spray is. A systematic uncertainty analysis was performed, and the measurement accuracy was also verified through a series of experiments on the completely vaporized fuel spray. The results show that the Molar Absorption Coefficient (MAC) of the test fuel, which is typically pressure and temperature dependent, is the major error source. The measurement error in the vapor determination has been shown to be approximately 18% under the assumption of constant MAC of the test fuel. Two application examples of the extended LAS technique were presented for exploring the dynamics and physical insight of the evaporating fuel sprays: diesel sprays injected by group-hole nozzles and gasoline sprays impinging on an inclined wall. © Springer-Verlag 2010.
Tomaschitz R.,Hiroshima University
Applied Physics B: Lasers and Optics | Year: 2010
Superluminal radiation from electrons accelerated in electromagnetic waves is investigated. The radiation field is a Proca field with negative mass-square, minimally coupled to the electron current. The spectrum is continuous in the ultra-relativistic regime, where steepestdescent asymptotics can be used to evaluate the power coefficients. The time averaging of Lissajous orbits in polarized wave fields is discussed, and the tachyonic spectral densities of electrons orbiting in intense laser beams are derived. In the ultra-relativistic limit, realized by high injection energy or high field intensity, the spectral functions are evaluated in closed form in terms of Airy integrals. In contrast to electromagnetic radiation, there is a longitudinal polarization component, and oscillations emerge at high beam intensity in the longitudinal and transversal spectral slopes, generated by the negative mass-square of the tachyonic quanta. The thermal ultra-relativistic electron plasma of two active galactic nuclei is analyzed in this regard, based on TeV spectral maps obtained with imaging air Cherenkov detectors. Specifically, tachyonic cascade fits are performed to γ-ray flares of the TeV blazars RGB J0152 + 017 and 3C 66A, and the transversal and longitudinal radiation components are disentangled in the spectral maps. The curvature of the spectral slopes is shown to be intrinsic, caused by the Boltzmann factor of the electronic source plasma radiating the tachyonic cascades. © Springer-Verlag 2010.
Tomaschitz R.,Hiroshima University
EPL | Year: 2010
Evidence for superluminal radiation in γ-ray burst (GRB) spectra is pointed out. The spectral maps of GRB 941017, GRB 990123, and GRB 990104 are analyzed. The superluminal radiation modes are generated by the shock-heated ultra-relativistic source plasma. The tachyonic radiation field is a real Proca field with negative mass-square, coupled to the electron gas by a frequency-dependent fine-structure constant. At GeV energies, the coupling constant approaches a limit value, so that the radiation field is minimally coupled to the electron current. In the soft γ-ray band, the interaction with the GRB plasma becomes nonlocal, due to the varying coupling strength depending on the energy of the radiated modes. The spectral fitting with tachyonic flux densities generated by nonlocal plasma currents is explained. Estimates of the tachyonic luminosity, temperature, and internal energy of the electronic source plasma are obtained from the spectral fits. © 2010 Europhysics Letters Association.
Sugiyama M.,Hiroshima University
Journal of Antibiotics | Year: 2015
As antibiotics act to inhibit the growth of bacteria, the drugs are useful for treating bacterial infectious diseases. However, microorganisms that produce antibiotics must be protected from the lethal effect of their own antibiotic product. In this review, the fruit of our group's current research on self-protection mechanisms of Streptomyces producing antibiotics that inhibit DNA, protein and bacterial cell wall syntheses will be described.
Asakawa M.,Hiroshima University |
Noguchi T.,Tokyo Medical University
Toxins | Year: 2014
Raw or dried gallbladders of cyprinid fish have long been ingested as a traditional medicine in the Asian countries, particularly in China, for ameliorating visual acuity, rheumatism, and general health; however, sporadic poisoning incidences have occurred after their ingestion. The poisoning causes complex symptoms in patients, including acute renal failure, liver dysfunction, paralysis, and convulsions of limbs. The causative substance for the poisoning was isolated, and its basic properties were examined. The purified toxin revealed a minimum lethal dose of 2.6 mg/20 g in mouse, when injected intraperitoneally. The main symptoms were paralysis and convulsions of the hind legs, along with other neurological signs. Liver biopsy of the euthanized mice clearly exhibited hepatocytes necrosis and infiltration of neutrophils and lymphocytes, suggesting the acute dysfunction of the liver. Blood tests disclosed the characteristics of acute renal failure and liver injury. Infrared (IR) spectrometry, fast atom bombardment (FAB) mass spectrometry, and 1H- and 13C-nuclear magnetic resonance (NMR) analysis indicated, a molecular formula of C27H48O8S, containing a sulfate ester group for the toxin. Thus, we concluded that the structure of carp toxin to be 5α-cyprinol sulfate (5α-cholestane-3α, 7α, 12α, 26, 27-pentol 26-sulfate). This indicated that carp toxin is a nephro- and hepato- toxin, which could be the responsible toxin for carp bile poisoning in humans. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
Katagiri T.,Hiroshima University
Journal of Bryology | Year: 2015
Trichocolea argentea Herzog, a little known South American species, is critically reviewed, based on the type material. Detailed morphological observations reveal the plants show (1) regularly 1-pinnate ramification pattern, (2) sublongitudinal leaf insertion, (3) poorly developed thick-walled stem cortex, and (4) shoot calyptra with well-developed perianth and calyptra, all character states typical of the genus Leiomitra (Trichocoleaceae), and so a new combination Leiomitra argentea (Herzog) T. Katag. is proposed. © British Bryological Society 2015.
Kotake Y.,Hiroshima University
Biological & pharmaceutical bulletin | Year: 2012
Organotins such as tributyltin are suspected of having multiple toxic effects in mammals, in addition to their endocrine-disrupting function. Endogenous organotin concentrations in human blood range from a few to a few hundred nM. In this review, we summarize recent findings on the mechanisms of toxicity of environmental organotins such as tributyltin (TBT) and triphenyltin (TPT) in mammals. TBT and TPT are potent inhibitors of mitochondrial ATP synthase, and a recent study suggests that TBT binds directly to ATP synthase. Organotins disturb steroid biosynthesis and degradation. TBT and TPT are dual agonists of retinoid X receptor (RXR) and peroxisome proliferator-activated receptor γ (PPARγ); they also induce the differentiation of adipocytes in vitro and in vivo, probably through PPARγ activation, suggesting that they may work as obesogens. Environmental organotins are also neurotoxic; they induce behavioral abnormality and are toxic to the developing central nervous system. In vitro studies have shown that organotins induce intracellular Ca(2+) elevation and glutamate excitotoxicity. Recently, it was reported that endogenous levels of TBT decrease expression of 2-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl)propanoic acid (AMPA) receptor subunit GluR2, leading to neuronal vulnerability. Most of the experimental studies have employed organotins at concentrations of μM order, and it remains important to clarify the molecular mechanisms of events induced by endogenous levels of environmental organotins.
Okada M.,Hiroshima Bunka Gakuen Two Year College |
Kakehashi M.,Hiroshima University
International Journal of Biometeorology | Year: 2014
Previous studies of autonomic nervous system responses before and after eating when controlling patient conditions and room temperature have provided inconsistent results. We hypothesized that several physiological parameters reflecting autonomic activity are affected by outdoor temperature before and after a meal. We measured the following physiological variables before and after a fixed meal in 53 healthy Japanese women: skin temperature, systolic and diastolic blood pressure, salivary amylase, blood glucose, heart rate, and heart rate variability. We assessed satiety before and after lunch using a visual analog scale (100 mm). We recorded outdoor temperature, atmospheric pressure, and relative humidity. Skin temperature rose significantly 1 h after eating (greater in cold weather) (P = 0.008). Cold weather markedly influenced changes in diastolic blood pressure before (P = 0.017) and after lunch (P = 0.013). Fasting salivary amylase activity increased significantly in cold weather but fell significantly after lunch (significantly greater in cold weather) (P = 0.007). Salivary amylase was significantly associated with cold weather, low atmospheric pressure, and low relative humidity 30 min after lunch (P < 0.05). Cold weather significantly influenced heart rate variability (P = 0.001). The decreased low frequency (LF)/high frequency (HF) ratio, increased Δ LF/HF ratio, and increased Δ salivary amylase activity imply that cold outdoor temperature is associated with dominant parasympathetic activity after lunch. Our results clarify the relationship between environmental factors, food intake, and autonomic system and physiological variables, which helps our understanding of homeostasis and metabolism. © 2014 The Author(s).
Gonzalez-Arroyo A.,Autonomous University of Madrid |
Okawa M.,Hiroshima University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013
The space-time reduced model of large N QCD with two adjoint Wilson fermions is constructed by applying the symmetric twist boundary conditions with nonvanishing flux k. For large but finite N=L2, the model should behave as the large N version of the ordinary lattice gauge model on a V=L4 space-time volume. We perform a comparison of the N dependence of several quantities in this model and in the k=0 model (corresponding to periodic boundary conditions). Although the Z4(N) symmetry seems unbroken in all cases, the N-dependence analysis favors the use of the same values of k and L for which the symmetry is also unbroken in the pure gauge case. In particular, the k=0 model, studied recently by several authors, shows a large and irregular dependence on N within our region of parameters. This makes this reduced model very impractical for extracting physical information about the large N lattice theory. On the contrary, the model for N=289=172 and large enough k gives consistent results, even for extended observables as Wilson loops W(R,T) up to R, T=8, matching the expected behavior for the lattice model with a 174 space-time volume. © 2013 American Physical Society.
Tsutaoka T.,Hiroshima University |
Kasagi T.,Tokuyama College of Technology |
Yamamoto S.,University of Hyogo |
Hatakeyama K.,University of Hyogo
Applied Physics Letters | Year: 2013
We have studied the relative complex permittivity (r r′- ir″) of copper granular composite materials containing coagulated Cu particles in the microwave range as well as the electrical conductivity. The insulator to metal transition was observed at the percolation threshold c 16.0 vol. . The enhancement of permittivity in the insulating state can be described by the Effective Cluster Model. Above the percolation threshold c, it was found that the Cu granular composites show negative permittivity spectra below a characteristic frequency f0 indicating the low frequency plasmonic state. Characteristic frequency tends to increase with particle content. © 2013 AIP Publishing LLC.
Shimahara H.,Hiroshima University
Journal of the Physical Society of Japan | Year: 2013
Noncentrosymmetric superconductors with various types of pairing interactions are systematically examined with particular focus on phenomena that originate from the differences between Fermi surfaces split by a strong spin-orbit coupling. In particular, when the spin-orbit coupling increases and one of the split Fermi surfaces disappears, the phase diagram and the structure of the gap function change drastically. For example, we examine the conditions for the transition from full-gap states to line-node states (FLT), which may explain the differences in the experimental results between the noncentrosymmetric superconductors Li2Pd3B and Li 2Pt3B discovered recently. The dominant pairing interactions and gap functions can be predicted to some extent by comparing the theoretical and experimental results for these compounds. For example, if the FLT occurs by replacing Pd with Pt, it is most likely that the superconductivity is mainly induced by charge-charge interactions, and if this is the case, the superconductivities in Li2Pd3B and Li2Pt 3B are an s-wave nearly spin-triplet state and a d-wave state that has both spin-singlet and triplet components of comparable weights, respectively. Comparing the theoretical phase diagrams in simple models, it is found that the FLT occurs in a wider realistic parameter region for charge-charge interactions, i.e., where short-range Coulomb repulsion is strong and p- and d-wave interactions are attractive, while it occurs in narrower rather unrealistic parameter regions for interactions of magnetic origin. It is also found that d-wave spin-triplet pairing may occur, when pairing interactions are of magnetic origin and anisotropic in spin space. Copyright © 2013 The Physical Society of Japan.
Poleschner H.,Free University of Berlin |
Ellrodt S.,Free University of Berlin |
Malischewski M.,Free University of Berlin |
Nakatsuji J.-Y.,Hiroshima University |
And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012
Joining the stable: The first examples of the highly instable selenenyl fluorides RSeF are prepared from the reaction on the tin selenide RSeSnMe 3 with XeF 2. Through the use of extremely large protecting groups (m-terphenyl ligands) which stabilizes the RSeF units against disproportionation, the compounds could be isolated and characterized by NMR spectroscopy and single-crystal structure analysis (see structure). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Saito T.,Tokai University |
Namera A.,Hiroshima University |
Osawa M.,Tokai University |
Aoki H.,Tokai University |
Inokuchi S.,Tokai University
Forensic Toxicology | Year: 2013
We provided toxicological analytical support for a fatal case of abuse of α-pyrrolidinovaleorophenone (α-PVP). Solid-phase microextraction (SPME) and capillary gas chromatography coupled to mass spectrometry (GC-MS) was employed to quantify the drug in whole blood. The whole blood concentration of the drug in the heart was 486 ng/ml. This is the first report of α-PVP intoxication as ascertained by mass spectrometric identification of α-PVP in whole blood. © 2013 Japanese Association of Forensic Toxicology and Springer Japan.
Kobayashi K.,Sophia University |
Ohtsuki T.,Sophia University |
Imura K.-I.,Hiroshima University
Physical Review Letters | Year: 2013
A global phase diagram of disordered weak and strong topological insulators is established numerically. As expected, the location of the phase boundaries is renormalized by disorder, a feature recognized in the study of the so-called topological Anderson insulator. Here, we report unexpected quantization, i.e., robustness against disorder of the conductance peaks on these phase boundaries. Another highlight of the work is on the emergence of two subregions in the weak topological insulator phase under disorder. According to the size dependence of the conductance, the surface states are either robust or "defeated" in the two subregions. The nature of the two distinct types of behavior is further revealed by studying the Lyapunov exponents. © 2013 American Physical Society.
Itoh T.,Hiroshima University
Journal of Photochemistry and Photobiology A: Chemistry | Year: 2010
Emission and excitation spectra of chromone and 6-fluorochromone have been measured in the vapor phase at different temperatures and pressures along with the absorption spectra. The emission is shown to consist of the 3(n, π*) phosphorescence accompanied by weak S1(n, π*) delayed fluorescence. It is inferred from the temperature dependence of the phosphorescence intensity that the 3(n, π*) state is located at energies below the 3(π, π*) state for chromone and 6-fluorochromone vapors. The relaxation processes in the vapor phase are discussed based on the pressure and excitation energy dependence of the relative phosphorescence yields. The data include the vibrational analyses of the emission spectra based on the results of the DFT calculations at the B3LYP/6-311 + G(p, d) level. © 2010 Elsevier B.V.
Itoh T.,Hiroshima University
Journal of Molecular Spectroscopy | Year: 2014
Emission spectra of 3- and 4-hydroxybenzaldehyde vapors have been measured along with the excitation and absorption spectra. It is inferred from the temperature dependence of the phosphorescence spectrum that the phosphorescence of 4-hydroxybenzaldehyde vapor originates from the T2(n, π*) state. In the case of 3-hydroxybenzaldehyde vapor, the emission is shown to consist of that of 3-hydroxybenzaldehyde and benzaldehyde vapors, with the latter molecule being generated as the result of photochemical decomposition of 3-hydroxybenzaldehyde. The interpretation of the emission spectrum of 3-hydroxybenzaldehyde is different from that reported previously. The rotational isomer responsible for appearance of the phosphorescence of 3-hydroxybenzaldehyde vapor is suggested based on DFT calculation and emission spectral data. © 2013 Elsevier Inc. All rights reserved.
Matsumoto M.,Hiroshima University
Rural and remote health | Year: 2013
For an equitable distribution of health resources, resource-allocation policies focus on rural and also remote areas, assuming that these areas are underserved. However, definitions of 'rural' and 'remote' vary, and are not necessarily synonymous with 'underserved'. This Japanese study evaluated the association between the rurality/remoteness of the community in which a patient lives and his/her geographic accessibility to dialysis facilities. Based on 1867 communities (census blocks) in Hiroshima Prefecture, Japan, predictive powers of five community-level rural/remote parameters (population size, population density, elderly rate, agriculture rate, and distance to the nearest city) were evaluated to identify communities where dialysis patients had a longer commute time to dialysis facilities. The proportion of low-access communities was examined when those communities were merged to form larger geographic units (four-level stepwise merger). One-way driving times of dialysis patients were used as the access parameter of a community and were calculated using geographic information systems based on the addresses of all the 7374 patients certified by municipalities as having renal disability, and on the addresses and capacities of all 98 dialysis facilities in Hiroshima. The average driving time was negatively correlated with population and population density, and positively correlated with elderly rate, agriculture rate, and distance to nearest city. When low-access was defined as >20, >30 & >40 min driving time, all rural/remote parameters showed better sensitivities (range 63.5-94.9%) than specificities (55.2-77.9%) to identify low-access communities, and positive predictive values were less than 50% for most parameters. When low-access was defined as >30 min driving time, the proportion of low-access communities substantially decreased when the geographic unit was expanded. In the administrative 'rural' area, the largest geographic unit, the percentage of low-access communities was 30%. In any definition of 'rural/remote', and in any definition of 'low-access', the rural/remote areas contain a substantial proportion of high-access communities. In addition, a substantial proportion of low-access communities was excluded from rural/remote areas. The accuracy of the term 'low-access' deteriorated when the geographic unit of analysis was expanded. In order to identify underserved areas precisely, it is necessary to set the geographic unit of analysis as small as possible and measure the geographic accessibility itself, rather than designate some areas as 'rural' or 'remote', based on conventional geographic/demographic/distance parameters.
Itoh T.,Hiroshima University
Chemical Physics Letters | Year: 2014
T2(n, π*) phosphorescence has been observed for 4-hyroxybenzaldehyde along with T1(π, π*) phosphorescence in a partially translucent 1,4-dichlorobenzene host upon increasing temperature. Quantitative analysis of the steady-state emission spectra and emission decay profiles measured as a function of temperature provides estimates for the excited-state energies and rate constants that characterize the excited-state dynamical behavior of 4-hydroxybenzaldehyde. It is shown that the successive occurrence of the T1(π, π*) and T 2(n, π*) phosphorescence is caused by the thermal repopulation from the T1 state. © 2013 Elsevier B.V. All rights reserved.
Itoh T.,Hiroshima University
Chemical Physics Letters | Year: 2014
Emission spectra of xanthone vapor have been measured at different temperatures along with the excitation and absorption spectra. Fluorescence from the S1(n, π*), 1A2 and phosphorescence from the T1(n, π*), 3A 2 states were separated to extract only the fluorescence spectrum. The vibrational structure of the fluorescence was interpreted in terms of the CO stretching mode and the modes combined with the CO stretching, showing a maximum near 24 000 cm-1. The locations of the S1 and T1 origins are observed at 26 940 and 25 700 cm-1, respectively. Analysis of the data includes the determination of the vibrational frequencies in the fluorescence and phosphorescence. © 2014 Elsevier B.V. All rights reserved.
Fujimaki K.,Prefectural University of Hiroshima |
Takahashi T.,Mihara Hospital |
Morinobu S.,Hiroshima University
PLoS ONE | Year: 2012
Background: Several reports on patients with chronic schizophrenia suggest that atypical versus typical antipsychotics are expected to lead to better quality of life (QOL) and cognitive function. Our aim was to examine the association of chronic treatment with typical or atypical antipsychotics with cognitive function, psychiatric symptoms, QOL, and drug-induced extrapyramidal symptoms in long-hospitalized patients with schizophrenia. Methodology and Principal Findings: The Hasegawa Dementia Scale-Revised (HDS-R), Brief Psychiatric Rating Scale (BPRS), the Schizophrenia Quality of Life Scale, translated into Japanese (JSQLS), and the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS) were used to evaluate cognitive function, psychiatric symptoms, QOL, and drug-induced extrapyramidal symptoms. We examined the correlation between the dose of antipsychotics and each measure derived from these psychometric tests. The student t-test was used to compare scores obtained from psychometric tests between patients receiving typical and atypical antipsychotics. Results showed significant correlations between chlorpromazine (CPZ)-equivalent doses of typical antipsychotics and atypical antipsychotics, and the total BPRS score and BPRS subscale scores for positive symptoms. CPZ-equivalent doses of typical antipsychotics were correlated with the JSQLS subscale score for dysfunction of psycho-social activity and DIEPSS score. Furthermore, the total BPRS scores, BPRS subscale score for positive symptoms, the JSQLS subscale score for dysfunction of psycho-social activity, and the DIEPSS score were significantly higher in patients receiving typical antipsychotics than atypical antipsychotics. Conclusion and Significance: These findings suggest that long-term administration of typical antipsychotics has an unfavorable association with feelings of difficulties mixing in social situations in patients with chronic schizophrenia. © 2012 Fujimaki et al.
Bosco J.P.,University of Delaware |
Sasaki K.,Hokkaido University |
Sadakane M.,Hiroshima University |
Ueda W.,Hokkaido University |
Chen J.G.,University of Delaware
Chemistry of Materials | Year: 2010
Three-dimensionally ordered macroporous tungsten carbide (3DOM WC) with varying pore size was synthesized using the "inverse-opal" method. Poly(methyl methacrylate} (PMMA) colloidal crystal template with sphere diameters ranging from 180 to 490 nm was used. Two synthesis procedures were performed, the first requiring calcination of tungsten impregnated PMMA colloidal template in air followed by carburization in H2/CH4/N2 atmosphere. The second procedure involved direct carburization of the tungsten impregnated template without prior calcination. The effect of Pt-modification of the template prior to carburization on the resulting material composition was also investigated. The material properties were evaluated using surface and bulk characterization techniques. Finally, cyclic voltammctry was used to investigate the methanol electro-oxidation activity of the 3DOM WC and Pt-modified 3DOM WC in acidic electrochemical environment. © 2009 American Chemical Society.
Ishikawa S.,Hiroshima University
Oncogene | Year: 2015
The transcribed-ultraconserved regions (T-UCRs) are a novel class of non-coding RNAs, which are absolutely conserved (100%) between the orthologous regions of the human, rat and mouse genomes. Previous studies have described that several T-UCRs show differential expressions in cancers and might be involved in cancer development. We investigated the transcriptional levels of representative 26 T-UCRs and determined the regions that were differently expressed in prostate cancer (PCa) and gastric cancer (GC). A quantitative reverse transcription-polymerase chain reaction analysis revealed the downregulation of Uc.158+A expression by a DNA methylation-associated mechanism, which was restored by 5-Aza-dC (5-aza-2′-deoxycytidine) treatment. Bisulfite genomic sequencing using cell lines and tissue samples demonstrated cancer-specific CpG hypermethylation in both GC and PCa. However, Uc.416+A was only overexpressed in GC and we identified an miR-153 binding site in the possible regulatory region of Uc.416+A using online databases. Along with a forced expression or knockdown of miR-153 in MKN-74 GC cells, the transcriptional levels of Uc.416+A were significantly disturbed. A luciferase reporter gene assay supported the direct regulation of Uc.416+A expression by miR-153. Furthermore, Uc.416+A was associated with cell growth through the regulation of IGFBP6 (insulin-like growth factor-binding protein 6) in GC. These findings suggest an oncogenic role of Uc.416+A in GC, which suggests that our approach would provide new insights into functional studies of T-UCRs in cancer biology.Oncogene advance online publication, 7 December 2015; doi:10.1038/onc.2015.445. © 2015 Macmillan Publishers Limited
Itoh T.,Hiroshima University
Journal of Photochemistry and Photobiology A: Chemistry | Year: 2016
Emission, excitation and absorption spectra of a new and short polyene, 2-(4-phenyl-1,3-butadien-1-yl)thiophene (PBT), have been measured under different conditions by varying temperature and solvent and in the vapor phase, along with those of 2-(2-phenylethenyl)-thiophene (PET). The presence of a forbidden excited singlet state, located at energies slightly below the strongly absorbing state, is indicated for PBT, although the forbidden state was not identified for PET. The emission of PBT consists of fluorescence from the allowed S2 and forbidden S1 states in low polarizable solvents, while it consists of florescence mainly from forbidden S1 in the vapor phase and that from allowed S1 state in high polarizable solvents. Quantitative analysis of the temperature dependence of the S1 and S2 fluorescence spectra provides the S1 and S2 state energies and physical parameters that characterize the excited states of PBT. © 2016 Elsevier B.V. All rights reserved.
Kang J.-D.,Nagoya University |
Tagawa H.,Hiroshima University
Earthquake Engineering and Structural Dynamics | Year: 2013
Vibration control systems are being used increasingly worldwide to provide enhanced seismic protection for new and retrofitted buildings. This paper presents a new vibration control system on the basis of a seesaw mechanism with viscoelastic dampers. The proposed vibration control system comprises three parts: brace, seesaw member, and viscoelastic dampers. In this system, only tensile force appears in bracing members. Consequently, the brace buckling problem is negligible, which enables the use of steel rods for bracing members. By introducing pre-tension in rods, long steel rods are applicable as bracing between the seesaw members and the moment frame connections over some stories. Seesaw mechanisms can magnify the damper deformation according to the damper system configuration. In this paper, first, the magnification factor, that is, the ratio of the damper deformation to the story drift, is delivered, which includes the rod deformation. Results of a case study demonstrate that the magnification factor of the proposed system is greater than unity for some cases. Seismic response analysis is conducted for steel moment frames with the proposed vibration control system. Energy dissipation characteristics are examined using the time-history response results of energy. The maximum story drift angle distributions and time-history response results of displacement show that the proposed system can reduce the seismic response of the frames effectively. Copyright © 2012 John Wiley & Sons, Ltd.
Nakano K.,Hiroshima University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012
The main contribution of this paper is to show optimal algorithms computing the sum and the prefix-sums on two memory machine models, the Discrete Memory Machine (DMM) and the Unified Memory Machine (UMM). The DMM and the UMM are theoretical parallel computing models that capture the essence of the shared memory and the global memory of GPUs. These models have three parameters, the number p of threads, the width w of the memory, and the memory access latency l. We first show that the sum of n numbers can be computed in time units on the DMM and the UMM. We then go on to show that time units are necessary to compute the sum. Finally, we show an optimal parallel algorithm that computes the prefix-sums of n numbers in time units on the DMM and the UMM. © 2012 Springer-Verlag.
Lee H.S.,Hiroshima University
Journal of Geophysical Research: Oceans | Year: 2013
Extreme sea levels due to storm surge and future sea level rise (SLR) in the year 2050 are estimated using ensemble empirical mode decomposition (EEMD) and extreme value analysis (EVA) based on long-term sea level records from Hiron Point (HP) on the coast of western Bangladesh. EEMD is an adaptive method that can detrend the nonlinear trend and separate the tidal motions from the original sea level records to reconstruct storm surge levels at HP. The reconstructed storm surge levels are then applied to EVA to obtain the extreme storm surges in the target return periods at a 95% confidence interval (CI). The 30, 50, and 100 year return levels at HP obtained by EVA are 1.59, 1.66, and 1.75 m. The SLR trend obtained from EEMD is 4.46 mm/yr over April 1990 to March 2009, which is larger than the recent altimetry-based global rate of 3.3 ± 0.4 mm/yr over the period from 1993 to 2007. The resulting SLR in 2050 is estimated as 0.34 m. Therefore, the extreme sea level in 2050 due to SLR and the storm surge at a 100 year return level would be 2.09 m (95% CI from 1.91 to 2.48 m). The SLR depends not only on changes in the mass and volume of sea water but also on other factors, such as local subsidence, river discharge, sediment and the effects of vegetation. The residual nonlinear trend of SLR obtained from EEMD can be regarded as an adaptive sea level after considering those factors and their nonlinearity. © 2013. American Geophysical Union. All Rights Reserved.
Takane Y.,Hiroshima University
Journal of the Physical Society of Japan | Year: 2016
An unbounded massless Dirac model with two nondegenerate Dirac cones is the simplest model for Weyl semimetals, which show the anomalous electromagnetic response of chiral magnetic effect (CME) and anomalous Hall effect (AHE). However, if this model is naively used to analyze the electromagnetic response within a linear response theory, it gives the result apparently inconsistent with the persuasive prediction based on a lattice model. We show that this serious difficulty is related to the breaking of current conservation in the Dirac model due to quantum anomaly and can be removed if current and charge operators are redefined to include the contribution from the anomaly. We demonstrate that the CME as well as the AHE can be properly described using newly defined operators, and clarify that the CME is determined by the competition between the contribution from the anomaly and that from low-energy electrons. © 2016 The Physical Society of Japan.
Umeo K.,Hiroshima University
Review of Scientific Instruments | Year: 2016
A developed alternating current calorimeter for measuring the absolute value of specific heat C of a very small sample under a pressure up to 10 GPa and low temperature below 10 K is described. A Bridgman anvil cell made of tungsten carbide with a top diameter of 3 mm is used. A hollow at the top prevents expansion of the sample space over the anvil top. Two chip resistors, which act as a thermometer and a heater, are mounted on the outer part of a copper-beryllium gasket with a frying pan-like shape. Thus, the thermometer is not pressurized. In order to isolate the gasket from the anvil thermally, diamond powder with a grain size of 0.25 μm is placed on the anvil top. Two jumps of C at the superconducting transitions of Pb (3.3 mg) and In (5.0 mg) are observed under various pressures up to 9 GPa, as clearly as those at the ambient pressure. © 2016 Author(s).
Ahmed A.M.,Kafr El Sheikh University |
Shimamoto T.,Hiroshima University
International Journal of Food Microbiology | Year: 2014
Foodborne pathogens are a major threat to food safety, especially in developing countries where hygiene and sanitation facilities are often poor. Salmonella enterica, Escherichia coli O157:H7 and Shigella spp. are among the major causes of outbreaks of foodborne diseases. This large-scale study investigated the prevalence of these foodborne pathogens in meat (beef and chicken) and dairy products collected from street vendors, butchers, retail markets and slaughterhouses in Egypt. A total of 1600 food samples (800 meat products and 800 dairy products) were analyzed using culture and PCR based methods. S. enterica, E. coli O157:H7 and Shigella spp. were detected in 69 (4.3%), 54 (3.4%) and 27 (1.7%) samples respectively. S. enterica serovar Typhimurium, S. enterica serovar Enteritidis, S. enterica serovar Infantis and non-typable serovars were detected in 28 (1.8%), 22 (1.4%), 16 (1.0%) and 3 (0.1%) samples respectively. All E. coli O157:H7 isolates were positive for stx1 and/or stx2 virulence toxin genes. Shigella flexneri, Shigella sonnei and Shigella dysenteriae were detected in 18 (1.2%), 7 (0.4%) and 2 (0.1%) samples respectively. The incidences of S. enterica and Shigella spp. were higher in meat products (53; 6.6% and 16; 2.0%, respectively) than in dairy products (16; 2.0% and 11; 1.4%, respectively), while, E. coli O157:H7 was higher in dairy products (29; 3.6%) than in meat products (25; 3.1%). The incidence of foodborne pathogens in meat and dairy products was determined in a large-scale survey in Africa. © 2013 Elsevier B.V.
Kato A.,Hiroshima University |
Baba M.,Marine Ecology Research Institute |
Suda S.,University of Ryukyus
Phycological Research | Year: 2013
The nongeniculate species Neogoniolithon brassica-florida (Harvey) Setchell et Mason is circumscribed as a polymorphic species with various gross morphologies due to it being synonymized with several previous species. However, small subunit rDNA and cox1 analyses showed that N.brassica-florida was polyphyletic, and strongly imply that crustose species lacking any protuberances such as Neogoniolithon fosliei (Heydrich) Setchell et Mason and species with protuberances or branches such as N.brassica-florida and N.frutescens (Foslie) Setchell et Mason should be treated as genetically different groups (species). Therefore, we propose the resurrection of N.frutescens. We also confirmed that N.trichotomum was distinguished from N.frutescens by slender uniform diameter branches, a conceptacle with a prominent ostiole, and large cox1 interspecific sequence differences. Male and female reproductive structures of N.trichotomum were illustrated for the first time. Neogoniolithon fosliei, was divided into three clades, each of which was recognized as a species complex based on interspecific level sequence differences within clade and morphological differences. Therefore, we treated the clade most similar to N.fosliei as N.fosliei complex (Clade B), and the other clades as respective complexes of N. cf. fosliei with yellow conceptacles (Clade A) or N. cf. fosliei with large conceptacles (Clade C). Of two species complexes (Clade A and B) were morphologically consistent with two entities of N.fosliei previously reported in the Ryukyu Islands, Japan, which is supported by their niche partitioning. DNA barcoding research of nongeniculate corallines can promote the finding of more reliable taxonomic characters and the understanding of their biological aspects. © 2013 Japanese Society of Phycology.
Sato T.,Hiroshima University
[Nihon kōshū eisei zasshi] Japanese journal of public health | Year: 2013
In 2009, epidemics of influenza (H1N1pdm) occurred worldwide. We evaluated 4 strategies for control and prevention of influenza (treatment with antiviral drugs, preventive actions, cancellation of large events, and school closures) by surveying the H1N1pdm epidemic in a geographically isolated rural town in Japan, and applying the epidemic to mathematical models. Subjects were 291 children attending nursery, primary, and junior high schools in Kounu town. The 4 strategies were evaluated by 3 types of mathematical models with varying parameters. The total number of infected cases, as reported in questionnaires, was 120. In the best-fitting model, treatment with antiviral drugs shortened the epidemic period from 31 to 23 days. Event cancellation reduced the total number of infected cases from 127.1 to 87.6 and the maximum number of cases from 63.7 to 41.7. In this simulation, 56 people were affected by the intervention. Immediate school closure reduced the total and maximum numbers of infected cases to 62.6 and 23.1, respectively. Statistical analysis confirmed that event cancellation and school closure are effective strategies for control of an influenza epidemic. The effective contact rate varied, which reflects a localized and rapidly spreading epidemic in a subpopulation.
Shimizu N.,Hiroshima University
Mutagenesis | Year: 2011
In addition to micronuclei that are formed from chromosomal material (the chromosome-type micronuclei), there are also micronuclei formed from extrachromosomal elements [the double minute (DM)-type micronuclei]. These two types of micronuclei are distinct entities, which exist and arise independently in a cell. A DM is a large extrachromosomal element that consists of amplified genes that are commonly seen in cancer cells; the aggregates of DMs can eventually be expressed as DM-type micronuclei. The question of how the DM-type micronuclei arise was answered by uncovering the quite unique intracellular behaviour of DMs during the cell cycle progression. This behaviour of DMs appeared to be common among the broad spectrum of extrachromosomal elements of endogenous, exogenous or artificial origin. Therefore, studying the biology of DM-type micronuclei will enable us to understand how these extrachromosomal structures may be retained within a cell or expelled from the nucleus and eliminated from the cell. This knowledge could also be used for the treatment of cancers and the development of a new mammalian host-vector system. © The Author 2010. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved.
Nakano K.,Hiroshima University
Proceedings - 2013 1st International Symposium on Computing and Networking, CANDAR 2013 | Year: 2013
The Unified Memory Machine (UMM) is a theoretical parallel computing model that captures the essence of the global memory access of GPUs. Although it is a good theoretical model for GPU computing, the performance analysis of parallel algorithms on it is sometimes complicated. The main contribution of this paper is to provide a useful gadget, the sequential memory access, that makes the computing time evaluation easy, and to show its application to the dynamic programming. The sequential memory access has two parameters: length n and fragmentation f. We first show that the sequential memory access of length n with fragmentation f can be done in O(nover w+nlover p+l+f) time units using p threads on the UMM with width w and latency l. We next show that the dynamic programming to solve the optimal polygon triangulation problem can be implemented in the UMM using the sequential memory access. The resulting implementation for a convex n-gon runs in O(n-3over w+n3lover p+nl) time units using p threads on the UMM with width w and latency l. We also prove that any implementation of the dynamic programming needs Omega(n3over w+n3lover p+nl) time units. Thus, our implementation is time optimal. © 2013 IEEE.
Tsuru T.,Hiroshima University
Journal of the Japan Petroleum Institute | Year: 2011
Hydrothermal stability is one of the most important technical challenges for hydrogen separation silica membranes. Metal doping into silica matrix was proposed, and it was found that Ni and Co were effective to improve the hydrothermal stability. Co-doped silica membranes showed a high permeance of 1.8×10-7 mol/(m2̇ṡPa) and H 2/N2 permeance ratio of 730 with hydrothermal stability (500 °C, steam partial pressure 300 kPa). Using hydrothermally stable silica membranes, permeation properties of helium, hydrogen and water vapor were examined based on the activation energy of permeation. The activation energy of H2 permeation correlated well with the permeance ratio of He/H2. The permeance ratios of H2/H2O of silica membranes are always larger than unity, although the kinetic diameter of hydrogen (0.289 nm) is larger than that of water (0.265 nm). Silica membranes were applied to bimodal catalytic membranes, which consisted of microporous silica top layer for selective permeation of hydrogen and a bimodal catalytic support layer where catalysts such as Ni were impregnated inside a bimodal support consisting of mesopores (γ-alumina) and macropores (α-alumina). Increased performance for production of hydrogen was confirmed by catalytic membranes for steam reforming of methane.
Okamura H.,Hiroshima University
Japanese Journal of Clinical Oncology | Year: 2011
Although rehabilitation for cancer patients is being practiced in clinical settings, it has not been very well recognized in cancer care. However, interest has been turning to cancer rehabilitation in recent years in association with advances in palliative care and the increasing numbers of patients who survive for long periods, while enduring symptoms caused by cancer or adverse effects associated with treatment. The fact that cancer patient rehabilitation fees were newly established in the 2010 revision of the Japanese medical service fees has propelled interest in this topic. Rehabilitation can be applied throughout the entire phase from the time of diagnosis to the terminal stage, and it is an approach that can involve psychosocial aspects as well as physical aspects. Although its effectiveness has not been adequately demonstrated, especially in the area of palliative medicine, rehabilitation for cancer patients is expected to be an important means of supporting the hopes of patients and their families, and attempting to maintain and improve patients' quality of life. © The Author (2011). Published by Oxford University Press. All rights reserved.
Gabriel A.A.,Hiroshima University |
Gabriel A.A.,University of the Philippines
Ultrasonics Sonochemistry | Year: 2012
The study determined the efficacy of Dynashock wave power ultrasound as an alternative processing technique for apple juice against a number of pathogenic and spoilage microorganisms. The effects of several implicit, intrinsic and extrinsic properties on the Dynashock wave inactivation of the microorganisms were also investigated. Results showed that acid adaptation increased the resistance of Escherichia coli O157:H7 and Salmonella spp. but decreased that of Listeria monocytogenes. Spoilage yeast mixed inoculum composed of Debaryomyces hansenii, Torulaspora delbrueckii, Clavispora lusitaniae, Pichia fermentans and Saccharomyces cerevisiae was found to be more resistant than any of the adapted or non-adapted pathogens. Among the individual, acid-adapted E. coli O157:H7, the MN-28 isolate was found most resistant; while three other individual isolates had greater resistance than the composited E. coli inoculum. Increased in pulp content decreased the efficacy of Dynashock waves, but co-treatment with ultraviolet-C rays significantly enhanced inactivation in the cloudy apple juice. The results demonstrated the potential of Dynashock wave technology, together with other antimicrobial hurdles as alternative juice processing technique/s. © 2011 Elsevier B.V. All rights reserved.
Ohishi W.,Radiation Effects Research Foundation |
Chayama K.,Hiroshima University
Clinical and Experimental Nephrology | Year: 2011
In recent years, hepatitis B virus (HBV) has been found to reproliferate either during or following immunosuppressive therapy or chemotherapy, with hepatitis caused by HBV reactivation now considered a serious issue. HBV reactivation is categorized into occurrence in HBsAg- and anti-HBe-positive asymptomatic carriers, and in HBsAg-negative, anti-HBc low-titer-positive, and/or anti-HBs-positive resolved HBV infection cases. Despite the fact that "clinical cure" is claimed for such resolved HBV cases, low levels of ongoing HBV production are now recognized as being sustained within the liver or in peripheral blood mononuclear cells, with the infection thus now considered to be virologically persistent. The risk of HBV reactivation rises as the level of immunosuppression intensifies, but in recent years HBV reactivation risk has been clearly shown to increase in cases of rituximab plus steroid-containing regimen for treatment of malignant lymphoma. In particular, the incidence of fulminant hepatitis caused by HBV reactivation in cases with resolved HBV infection is reported to be higher than that brought about by acute hepatitis B. Therefore, for all cases in which immunosuppressive therapy or chemotherapy treatment regimens are used, screening for HBV infection and appropriate management in accordance with the status of HBV-related markers are crucial, aimed at preventing occurrence of HBV reactivation. The foundation of the aforementioned management, regardless of HBsAg status, is administration of nucleoside analogues, with their powerful anti-viral properties, when HBV DNA levels reach detectable levels. © 2011 Japanese Society of Nephrology.
Suzuki T.,Hokkaido University |
Suzuki T.,Hiroshima University |
Hara H.,Hokkaido University
Journal of Nutritional Biochemistry | Year: 2011
The gastrointestinal tract provides a physical barrier to the diffusion of foreign materials from the lumen into the circulatory system. Impairment of the intercellular tight junction (TJ) shield, which is the major determinant of intestinal barrier function, is associated with various diseases. Dietary flavonoids demonstrate various beneficial effects on our health; however, the information regarding their effects on TJ function is quite limited. To date, four flavonoids - epigallocatechin gallate (EGCG), genistein, myricetin and quercetin - have been reported to exhibit promotive and protective effects on intestinal TJ barrier functions. Genistein, a major soybean isoflavone, protects TJ barrier function against oxidative stress, acetaldehyde, enteric bacteria and inflammatory cytokines. Genistein blocks the tyrosine phosphorylation of the TJ proteins induced by oxidative stress and acetaldehyde, which results in the disassembly of the proteins from the junctional complex. Quercetin, a flavonol, enhances intestinal TJ barrier function through the assembly and expression of TJ proteins. The change in phosphorylation status is responsible for the quercetin-mediated assembly of TJ proteins. TJ protein induction has an additional role in this effect. This review presents the recent advances in our understanding of the flavonoid-mediated promotive and protective effects on intestinal TJ barrier function with a particular focus on intracellular molecular mechanisms. © 2011 Elsevier Inc.
Kosseva M.R.,Hiroshima University
Food and Bioprocess Technology | Year: 2011
The purpose of this review is to emphasize existing trends and recent advances in the application of immobilized cell technology so as to implement some innovations in food industry associated with processing, preservation, and storage of the products based on the food safety issues. Attention is focused on the engineering aspects of the immobilized cell techniques with emphasis on the mass-balance-based mathematical modeling of the system. Some aspects of models for safety, quality, and competitiveness of the food processing sector are also presented. Ultimately, development of products with novel properties within the alcoholic beverages, meat processing/preservation, manufacture of cheese and bread, sweeteners and pigments, as well as nutraceuticals is also addressed. © 2010 Springer Science + Business Media, LLC.
Katagiri H.,Hiroshima University |
Kato K.,Hiroshima Institute of Technology |
Hasuike T.,Osaka University
Expert Systems with Applications | Year: 2012
This paper considers a minimum spanning tree problem under the situation where costs for constructing edges in a network include both fuzziness and randomness. In particular, this article focuses on the case that the edge costs are expressed by random fuzzy variables. A new decision making model based on a possibility measure and a value at risk measure is proposed in order to find a solution which fully reflects random and fuzzy information. It is shown that an optimal solution of the proposed model is obtained by a polynomial-time algorithm. © 2012 Elsevier Ltd. All rights reserved.
Tanabe S.,Hiroshima University
International Reviews of Immunology | Year: 2013
Probiotics and gut microbiota have a significant impact on gut homeostasis in the host. Recent clinical studies demonstrated the ameliorative features of several kinds of probiotics in intestinal disorders, such as inflammatory bowel diseases (IBDs). Interleukin (IL)-17 is a potent inflammatory cytokine, and T-helper (Th)17 cells and other IL-17-producing cells are involved in the pathogenesis of IBD. Multiple mechanisms of action have been suggested to explain the protective anti-inflammatory effects of probiotics in intestinal inflammation, including the immunoregulation and suppression of Th17 activity and IL-17 production in part by signaling through pattern-recognition receptors such as Toll-like receptor family. However, steady-state Th17 cells have an important role in host defense against fungi and bacteria. Interestingly, recent studies revealed that specific commensal bacterial species such as segmented filamentous bacteria (SFB) induce the accumulation of Th17 cells in the small intestine in many species, including mice. It is important to determine the mechanisms by which intestinal Th17 cells are induced by SFB and whether these or other bacteria with similar properties are present in the human intestine. This brief review focuses on the interaction between probiotics/microbiota and Th17 cells during inflammation (war) and during steady-state homeostatic regulation (peace). © 2013 Informa Healthcare USA, Inc.
Hofmann H.F.,Hiroshima University |
Hofmann H.F.,Chiyoda Corporation
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2014
Recent results obtained in quantum measurements indicate that the fundamental relations between three physical properties of a system can be represented by complex conditional probabilities. Here, it is shown that these relations provide a fully deterministic and universally valid framework on which all of quantum mechanics can be based. Specifically, quantum mechanics can be derived by combining the rules of Bayesian probability theory with only a single additional law that explains the phases of complex probabilities. This law, which I introduce here as the law of quantum ergodicity, is based on the observation that the reality of physical properties cannot be separated from the dynamics by which they emerge in measurement interactions. The complex phases are an expression of this inseparability and represent the dynamical structure of transformations between the different properties. In its quantitative form, the law of quantum ergodicity describes a fundamental relation between the ergodic probabilities obtained by dynamical averaging and the deterministic relations between three properties expressed by the complex conditional probabilities. The complete formalism of quantum mechanics can be derived from this one relation, without any axiomatic mathematical assumptions about state vectors or superpositions. It is therefore possible to explain all quantum phenomena as the consequence of a single fundamental law of physics. © 2014 American Physical Society.
Nakano K.,Hiroshima University
Proceedings - IEEE 27th International Parallel and Distributed Processing Symposium Workshops and PhD Forum, IPDPSW 2013 | Year: 2013
The Discrete Memory Machine (DMM) and the Unified Memory Machine (UMM) are theoretical parallel computing models that capture the essence of the shared memory access and the global memory access of GPUs. The main contribution of this paper is to introduce the Hierarchical Memory Machine (HMM), which consists of multiple DMMs and a single UMM. The HMM is a more practical parallel computing model which reflects the architecture of current GPUs. We present several fundamental algorithms on the HMM. First, we show that the sum of n numbers can be computed in O(n/w + nl/p + l + log n) time units using p threads on the HMM with width ω and latency l, and prove that this computing time is optimal. We also show that the direct convolution of m and m + n-1 numbers can be done in O(n/w + mn/dw + nl/p + l+ log m) time units using p threads on the HMM with d DMMs, width ω, and latency l. Finally, we prove that our implementation of the direct convolution is time optimal. © 2013 IEEE.
Ito T.,Hiroshima University
Plant signaling & behavior | Year: 2011
Ca2+-dependent protein kinases (CDPKs) are encoded by a multigene family and are thought to play central roles in Ca2+ signaling in plants. Although the primary structures of CDPK isoforms are highly conserved, several studies suggested a distinct physiological function for each CDPK isoform in plants. Hence, there should be mechanisms by which individual CDPK specifically recognizes its substrate. Recently, the variable N-terminal domain of NtCDPK1 was shown to play an essential role in the specific recognition of the substrate. Because the variable N-terminal domain of other CDPKs may also be involved in the substrate recognition, the search for interacting proteins of the variable N-terminal domain would provide important clues to identify the physiological substrates of each CDPK. Additionally, manipulation of the variable N-terminal domain may enable us to engineer the substrate specificity of CDPK, leading a rational rewiring of cellular signaling pathways.
Takumi T.,Hiroshima University |
Takumi T.,Japan Science and Technology Agency
Journal of Neurodevelopmental Disorders | Year: 2011
Autism is a neurodevelopmental disorder that manifests in childhood as social behavioral abnormalities, such as abnormal social interaction, impaired communication, and restricted interest or behavior. Of the known causes of autism, duplication of human chromosome 15q11-q13 is the most frequently associated cytogenetic abnormality. Chromosome 15q11-q13 is also known to include imprinting genes. In terms of neuroscience, it contains interesting genes such as Necdin, Ube3a, and a cluster of GABAA subunits as well as huge clusters of non-coding RNAs (small nucleolar RNAs, snoRNAs). Phenotypic analyses of mice genetically or chromosomally engineered for each gene or their clusters on a region of mouse chromosome seven syntenic to human 15q11-q13 indicate that this region may be involved in social behavior, serotonin metabolism, and weight control. Further studies using these models will provide important clues to the pathophysiology of autism. This review overviews phenotypes of mouse models of genes in 15q11-q13 and their relationships to autism. © 2011 Springer Science+Business Media, LLC.
Tomikawa K.,Hiroshima University
ZooKeys | Year: 2015
A new species of anisogammarid amphipod, Jesogammarus (Jesogammarus) ikiensis sp. n., is described from freshwaters in the Iki Island, Nagasaki Prefecture, Japan, based on results of morphological and molecular analyses. The new species is distinguished from all members of the genus by the combination of small number of setae on dorsal margins of pleonites 1–3, short and small number of setae on posterior margins of peduncular articles of antennae, mandibular article 1 without setae, well developed posterior lobes of accessory lobes of coxal gills on gnathopod 2 and pereopods 3–5, and pectinate setae on palmar margin of female gnathopod 2. A key to all the species of Jesogammarus is provided. © 2015, Pensoft Publishers. All rights reserved.
Yabuki A.,Hiroshima University
Advanced Powder Technology | Year: 2011
This review summarizes research on particle-induced damage and the subsequent repair of metallic materials. Metallic materials are damaged by solid particle impact via two damage processes: repeated plastic deformation and cutting. At a certain low-impact velocity, the particle does not skid, resulting in only plastic deformation with no damage by cutting. The critical impact velocity has been theoretically derived. Self-healing coatings for repair of damaged materials have been investigated. A fluorine polymer coating has self-healing properties, which are improved by the addition of metal particles. A self-healing coating that uses particles and an organic healing agent has also been developed. © 2010 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
Miura H.,Nagoya City University |
Kobayashi R.,Hiroshima University
Crystal Growth and Design | Year: 2015
We propose a new formulation for numerically simulating step dynamics on growing crystal surfaces in the framework of a phase-field technique. The step advancement rate is proportional to a supersaturation at the crystal surface when the growth units in the ambient phase are integrated to the step front directly (direct integration hypothesis). We conduct numerical simulations of some standard step dynamics problems: the advancement of a straight step, the growth or dissolution of a two-dimensional island, and the vertical growth of the crystal surface due to single or multiple screw dislocations. During evaluations, our phase-field model accurately calculated the rate of advancement of a straight step for various supersaturations. The calculated time variation of the radius of the two-dimensional island showed good agreement with the exact solution. The vertical growth rate due to screw dislocations qualitatively agreed with the predictions of the classical theory of Burton, Cabrera, and Frank. Our simple formulation requires only a single parabolic partial differential equation to be solved numerically. Thus, our phase-field model provides a simple numerical tool for a quantitative step-by-step trajectory calculation, when the advancing velocity of each step follows the direct integration hypothesis. © 2015 American Chemical Society.
Yagi M.,Japan National Astronomical Observatory |
Komiyama Y.,Japan National Astronomical Observatory |
Yoshida M.,Hiroshima University
Astrophysical Journal Letters | Year: 2012
From Hα narrowband observations, we identified three Hα emitting regions in the direction of Magellanic Stream IV (MS IV). They consist of three parallel filaments of 2 arcmin width and 6-30 arcmin length at 12 arcmin intervals. Their mean surface brightness (SB) is 2 × 10 -18 erg s-1 cm-2 arcsec-2. Because of their low SB, the regions were not detected in previous Hα surveys. In the H I map, the position of the filaments overlap MS, suggesting that they are parts of the MS, but there also exists a local H I structure. If the filaments are associated with the MS, the sizes are 30 pc × 100-500 pc. The filaments lie at the leading edge of a downstream cloud, which supports shock heating and its propagation (shock cascade) model for the ionizing source. If they are local objects, on the other hand, Fossil Strömgren Trails of more than two stars is a possible interpretation, and the sizes would be 0.1 pc × 0.3-1.5 pc at 180 pc distance. The positional information of the Hα filaments presented in this Letter enables future spectroscopic observations to clarify their nature. © 2012 The American Astronomical Society. All rights reserved.
Lee H.S.,Hiroshima University
Journal of Coastal Research | Year: 2013
The winter East Sea, a semi-enclosed sea surrounded by Korea in the west, Japan in the east and south and Russia in the north, normally experiences rough sea conditions due to East Asian monsoon and winter storms. In April 2012, record-breaking abnormally high waves, significant wave heights of 11.21 m and 12.39 m and significant wave periods of 13.6 sec and 14.3 sec at Akita and Yamagata GPS buoy sites, respectively, were observed along the Tohoku coast in the East Sea side of Japan. It was due to a well- and fast-developed low pressure passing through the East Sea. This paper describes how a low pressure could be grown so rapidly to tropical cyclone level in this time and numerical hindcast results for future forecast and engineering purpose. With respect to the meteorological condition, it is found that strong convective motion due to latent heat and water vapor from Tsushima Warm Current together with an accompanied front increases a pressure gradient at tropopause level accelerating the low growth. In the hindcast using an atmosphere-wave modeling system, two different initial and boundary condition data, NCEP FNL and JMA GSM, are used for applicability test. The result with NCEP FNL data shows a better agreement with observations in terms of surface winds. The observed peaks of significant wave height and period by Akita and Yamagata GPS buoy are captured well in both results. It is also found that the vertical resolution of initial and boundary condition data is important in atmospheric modeling; the higher vertical resolution tends to produce a deeper storm with lower central pressure and strong convective motion. © Coastal Education & Research Foundation 2013.
Takakura Y.,Hiroshima University
Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland | Year: 2010
Surgical resection has been the first choice of treatment for resectable pulmonary metastases from colorectal cancer. However, early intrapulmonary recurrence is often observed and appropriate assessment of prognostic factors is controversial. The aim of this study was to define the factors affecting survival and intrapulmonary recurrence after surgical treatment of metastatic pulmonary tumours from colorectal cancer. A retrospective analysis was performed of 56 consecutive patients who underwent pulmonary resection for colorectal metastases with a focus on prognostic factors and risk factors for intrapulmonary recurrence. The overall 5-year survival rate was 48.2%. In a univariate analysis, a short disease-free interval (DFI), multiple pulmonary metastases and abnormal prethoracotomy carcinoembryonic antigen (CEA) levels were poor prognostic factors. In a multivariate analysis, a short DFI and abnormal prethoracotomy CEA levels were independent prognostic factors. Twenty-two (39.3%) of the 56 patients had recurrences in the remnant lung after resection for pulmonary metastases, and 8 (36.4%) of these 22 patients underwent repeated pulmonary resections. The median DFI between first and second lung metastasis was 13 months. Univariate analyses revealed that multiple and bilateral lung metastases were risk factors for intrapulmonary recurrence. There was also a strong correlation between the DFI for intrapulmonary recurrence after the first pulmonary resection and the DFI for first pulmonary metastases. A short DFI was a risk factor for early tumour recurrence after resection for pulmonary metastases. The DFI might reflect oncological characteristics such as the tumour doubling time in colorectal cancer.
Ohashi N.,Hiroshima University
JACC. Cardiovascular imaging | Year: 2010
We sought to investigate the association between visceral adipose tissue (VAT) with the presence, extent, and characteristics of noncalcified coronary plaques (NCPs) using 64-slice computed tomography angiography (CTA). Although visceral adiposity is associated with cardiovascular events, its association with NCP burden and vulnerability is not well known. The study population consisted of 427 patients (age 67 ± 11 years; 63% men) with proven or suspected coronary artery disease who underwent 64-slice CTA. We assessed the presence and number of NCPs for each patient. The extent of NCP was tested for the difference between high (≥ 2) and low (≤ 1) counts. We further evaluated the vulnerable characteristics of NCPs with positive remodeling (remodeling index >1.05), low CT density (≤ 38 HU), and the presence of adjacent spotty calcium. Plain abdominal scans were also performed to measure the VAT and subcutaneous adipose tissue area. A total of 260 (61%) patients had identifiable NCPs. Multivariate analyses revealed that increased VAT area (per 1 standard deviation, 58 cm(2)) was significantly associated with both the presence (odds ratio [OR]: 1.68; 95% confidence interval [CI]: 1.28 to 2.22) and extent (OR: 1.31; 95% CI: 1.03 to 1.68) of NCP. Other body composition measures, including subcutaneous adipose tissue area, body mass index, and waist circumference were not significantly associated with either presence or extent of NCP. Increased VAT area was also independently associated with the presence of NCP with positive remodeling (OR: 1.71; 95% CI: 1.18 to 2.53), low CT density (OR: 1.69; 95% CI: 1.17 to 2.47), and adjacent spotty calcium (OR: 1.52; 95% CI: 1.03 to 2.27). Increased VAT area was significantly associated with NCP burden and vulnerable characteristics identified by CTA. Our findings may explain the excessive cardiovascular risk in patients with visceral adiposity, and support the potential role of CTA to improve risk stratification in such patients. Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Kisaka S.,Hiroshima University |
Kawanaka N.,Hebrew University of Jerusalem
Monthly Notices of the Royal Astronomical Society | Year: 2012
Recent γ-ray observations by Fermi Gamma-Ray Space Telescope suggest that the γ-ray millisecond pulsar (MSP) population is separated into two subclasses with respect to pair multiplicity. Here, we calculate the cosmic-ray electron/positron spectra from MSPs. Based on the assumption of equipartition in the pulsar-wind region, the typical energy of electrons/positrons ejected by a MSP with pair multiplicity of the order of unity is ∼50TeV. In this case, we find that a large peak in the 10-50TeV energy range would be observed in the cosmic-ray electron/positron spectrum. Even if the fraction of pair-starved MSPs is 10per cent, a large peak would be detectable in future observations. We also calculate the contribution from MSPs with high pair multiplicity to the electron/positron spectrum. We suggest that if the multiplicity of the dominant MSP population is ∼10 3, electrons/positrons from this population may contribute to the observed excess from the background electron/positron flux and positron fraction. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.
Ahmed A.M.,Kafr El Sheikh University |
Shimamoto T.,Hiroshima University
International Journal of Food Microbiology | Year: 2015
Shiga toxin-producing Escherichia coli (STEC) O157:H7 is an important food-borne pathogen that has been implicated in numerous disease outbreaks worldwide. Little is known about the extent and molecular basis of antimicrobial resistance in STEC O157:H7 of food origin. Therefore, the current study aimed to characterize the genetic basis of multidrug resistance in 54 STEC O157:H7 strains isolated from 1600 food samples (800 meat products and 800 dairy products) collected from different street venders, butchers, retail markets, and slaughterhouses in Egypt. Thirty-one of 54 (57.4%) isolates showed multidrug resistance phenotypes to at least three classes of antimicrobials. The highest incidence of antimicrobial resistance was to kanamycin (96.8%), followed by spectinomycin (93.6%), ampicillin (90.3%), streptomycin (87.1%), and tetracycline (80.6%). PCR and DNA sequencing were used to screen and characterize integrons and antibiotic resistance genes, and 29.6% and 5.6% of isolates were positive for class 1 and class 2 integrons, respectively. β-Lactamase-encoding genes were identified in 63.0% of isolates as follows: blaTEM-1 and blaTEM-52 in 35.2% and 1.9% isolates respectively; blaCMY-2 in 13.0% isolates; blaCTX-M in 5.6% isolates; blaSHV-12 in 5.6% isolates; and blaOXA-1 in 1.9% isolate. The plasmid-mediated quinolone resistance genes were identified in 13.0% of isolates as follows: qnrB, qnrS, and aac(6')-Ib-cr in 5.6%, 3.7%, and 3.7% isolates, respectively. Finally, the florfenicol resistance gene floR was identified in 7.4% of isolates. This study demonstrated that meat and dairy products are potential sources of multidrug resistant STEC O157:H7. To our knowledge, this is the first report of the occurrence of class 2 integrons, qnrB, qnrS, and aac(6')-Ib-cr in STEC O157:H7. © 2014.
Moriya J.,Japan Society for the Promotion of Science |
Moriya J.,Hiroshima University |
Tanno Y.,University of Tokyo
Journal of Behavior Therapy and Experimental Psychiatry | Year: 2011
While impaired attentional disengagement from threatening stimuli is thought to enhance social anxiety, it is unclear when the impaired disengagement occurs accurately. We used a gap task (Experiment 1) and an overlap task (Experiment 2) to reveal the impaired attentional disengagement from angry faces in socially anxious people with non-treatment seeking undergraduates. High (N = 17 in Experiments 1 and 2) and low socially anxious people (N = 17 in Experiment 1 and 19 in Experiment 2) were asked to fixate on an angry or neutral face presented at the center of a screen. Then, they discriminated the peripheral target stimuli. When there was a temporal gap between the face and target in Experiment 1 (gap task), the reaction times (RTs) for angry and neutral faces did not differ for all participants. However, when there was no gap and the face continued to appear in Experiment 2 (overlap task), the RTs for angry faces in high socially anxious people were longer than those for neutral faces after presentation times of 300 ms or longer. In low socially anxious people, the RTs following the angry and neutral faces did not differ. These results suggest that high socially anxious people face difficulty in disengaging attention from angry faces after recognizing them. © 2010 Elsevier Ltd. All rights reserved.
Onishi H.,Hiroshima University
Nihon Hoshasen Gijutsu Gakkai zasshi | Year: 2012
The present study aims to quantitatively investigate a normal database (NDB) created under the same acquisition and reconstruction conditions for three gamma camera systems (four types of collimator systems) with use of three-dimensional stereotactic surface projections (3D-SSP). We rebuilt a NDB with use of the N-isopropyl-p-(123)I-iodoamphetamine ((123)I-IMP) SPECT data derived from 30 healthy individuals at 20 institutions nationwide. We standardized the acquisition and reconstruction conditions, evaluated Z scores using patient data (PD) and examined each compensation effect. Z scores determined using the advanced NDB were the same value. Artifacts were often generated in Z score maps derived from the conventional NDB (CONDB). The Z score of the own site NDB (OWNDB) was 70% of that calculated based on the CONDB. The combinatorial difference in compensation (scatter and attenuation) resulted in many artifacts being generated in Z score map images. More artifacts were generated in Z score map images using the novel NDB compared with the CONDB. The novel NDB was comparable to the performance of OWNB. The accuracy of brain function image analysis can be improved the reconstruction conditions and correcting for scatter and attenuation on both the novel NDB and PD.
Itoh T.,Hiroshima University
Molecular Physics | Year: 2015
Fluorescence, fluorescence excitation and absorption spectra of 1,3,5-heptatrienylbenzene (MPP3) have been measured in the static vapour phase and in solution. It is shown that the MPP3 vapour exhibits prompt S2 and S1 fluorescence. The presence of two different mechanisms for the occurrence of the S2 fluorescence is demonstrated for MPP3. That is, the S2 fluorescence in the vapour phase is prompt fluorescence, the rate of which is fast enough to compete with internal conversion from S2 to S1, while in solution the S2 fluorescence occurs as the result of the thermal activation of the S1 state. The relaxation processes were discussed and the fluorescence property was compared with that of diphenylhexatriene. © 2015 Taylor & Francis.
Oyama J.-I.,Saga University |
Higashi Y.,Hiroshima University |
Node K.,Saga University
Cardiovascular Diabetology | Year: 2014
An impaired endothelial function has been recognized in the early stage of atherosclerosis, and is a major factor affecting the future development of cardiovascular events. Type 2 diabetes mellitus (T2DM) is widely prevalent, and is one of the most important risk factors for cardiovascular disease. T2DM is associated with increases in both morbidity and mortality, particularly from cardiovascular disease.New therapies based on the incretin hormone and its actions are now becoming widely used, and appear to offer advantages over conventional therapies by keeping the body weight steady and limiting hypoglycemia, while also achieving attractive glycemic control. However, there is little data available about the effects of incretins on the cardiovascular system.This review will focus on the effects of incretin therapies, including glucagon-like peptide-1 (GLP-1) analogs and dipeptidyl peptidase (DPP)-4 inhibitors, on the endothelial function, and will discuss the potential mechanisms underlying these effects. © 2014 Oyama et al.; licensee BioMed Central Ltd.
Dasgupta S.,Indian Institute of Science |
Bose S.,Presidency University of India |
Das K.,Bengal Engineering and Science University |
Das K.,Hiroshima University
Precambrian Research | Year: 2013
We present possible tectonic models for two crustal domains of the Proterozoic Eastern Ghats Belt, India based on recent petrological, geophysical and geochronological data. Although both the domains presently expose deep crustal sections, they evolved in two distinct time segments of the Precambrian through accretion-collision processes. This is why we argue that no unique model can explain the complexities of the belt. The southern part of the belt evolved through subduction-dominated accretionary processes encompassing India, east Antarctica, Australia and Laurentia as part of supercontinent Columbia during the span of ca. 1.90-1.60. Ga. To the contrary, the central domain witnessed a prolonged accretion-collision history initiated at ca. 1.50. Ga and culminated at ca. 0.90. Ga with the formation of supercontinent Rodinia. The latter united cratonic India with east Antarctica as a separate continent Enderbia that existed until about ca. 0.50. Ga. The pre-1.50. Ga history of this domain is ambiguous at the present state of knowledge. The northern domain has a much younger (ca. 0.90-0.50. Ga) tectonothermal history which is unrelated to either of the studied domains. The present models explain the reported petrotectonic processes including the ultra high temperature metamorphism in both the domains. The episodic growth of the Eastern Ghats Belt matches with Proterozoic supercontinent cycles. © 2012 Elsevier B.V.
Hofmann H.F.,Hiroshima University |
Hofmann H.F.,Chiyoda Corporation
Physical Review Letters | Year: 2012
A statistical analysis of optimal universal cloning shows that it is possible to identify an ideal (but nonpositive) copying process that faithfully maps all properties of the original Hilbert space onto two separate quantum systems, resulting in perfect correlations for all observables. The joint probabilities for noncommuting measurements on separate clones then correspond to the real parts of the complex joint probabilities observed in weak measurements on a single system, where the measurements on the two clones replace the corresponding sequence of weak measurement and postselection. The imaginary parts of weak measurement statics can be obtained by replacing the cloning process with a partial swap operation. A controlled-swap operation combines both processes, making the complete weak measurement statistics accessible as a well-defined contribution to the joint probabilities of fully resolved projective measurements on the two output systems. © 2012 American Physical Society.
Panaccione G.,CNR Institute of Materials |
Kobayashi K.,Hiroshima University |
Kobayashi K.,Japan National Institute of Materials Science
Surface Science | Year: 2012
The electronic properties of surfaces and buried interfaces can vary considerably in comparison to the bulk. In turn, analyzing bulk properties, without including those of the surface, is understandably challenging. Hard X-ray photoelectron spectroscopy (HAXPES) allows the well known ability of photoemission to interrogate the electronic structure of material systems with bulk volume sensitivity. This is achieved by tuning the kinetic energy range of the analyzed photoelectrons in the multi-keV regime. This unique ability to probe truly bulk properties strongly compliments normal photoemission, which generally probes surface electronic structure that is different than the bulk selected examples of HAXPES and possible implications towards the study of complex oxide-based interfaces and highly correlated systems are discussed. © 2011 Elsevier B.V. All rights reserved.
Tomaschitz R.,Hiroshima University
Monthly Notices of the Royal Astronomical Society | Year: 2012
The fine structure of the temperature power spectrum of the cosmic microwave background (CMB) radiation is investigated in the presently accessible multipole range up to l ∼ 10 4. The temperature fluctuations are reproduced by an isotropic Gaussian random field on the unit sphere, whose Green function is defined by a Hermitian matrix kernel inferred from the data sets by way of spectral fits. The reconstruction of the temperature autocorrelation function from the measured multipole moments C l is a classical inverse problem, which does not require specification of cosmic evolution equations for the photon density. The scale-invariant correlation function admits a multipole expansion in zonal spherical harmonics. The multipole coefficients are obtained as averages over Hermitian spectral matrices determining the angular power spectrum of the spherical random field. The low-l multipole regime of the CMB temperature fluctuations is composed of overlapping Gaussian peaks, followed by an intermediate oscillatory regime manifested by a modulated exponentially decaying C l slope. The high-l regime above l ∼ 4000 comprises a power-law ascent with exponential cut-off. The fine structure of the Gaussian, oscillatory and high-l regimes is reproduced by zooming into the respective l intervals on linear and logarithmic scales. © 2012 The Author Monthly Notices of the Royal Astronomical Society © 2012 RAS.
Fujimura T.,RIKEN |
Kawamoto S.,Hiroshima University
Allergology International | Year: 2015
The high prevalence of Japanese cedar pollinosis in Japan is associated with a negative impact on the quality of life of patients, as well as significant loss of productivity among the workforce in early spring, thus representing a serious social problem. Furthermore, the prevalence is increasing, and has risen by more than 10% in this decade. Cry j 1 and Cry j 2 were identified as the major allergens in Japanese cedar pollen (JCP), and in 2004, the existence of other major and minor allergens were revealed by a combination of two-dimensional electrophoresis and immunoblotting analysis. Allergenome analysis identified a chitinase, a lipid transfer protein, a serine protease, and an aspartic protease as novel IgE-reactive allergens in patients with JCP allergy. Thaumatin-like protein (Cry j 3) was shown to be homologous to Jun a 3, a major allergen from mountain cedar pollen. Isoflavone reductase-like protein was also characterized in a study of a JCP cDNA library. The characterization of component allergens is required to clarify the sensitizer or cross-reactive elicitor allergens for component-resolved diagnosis (CRD). Increasing evidence from numerous clinical trials indicates that CRD can be used to design effective allergen-specific immunotherapy. In this review, we summarize the eight characterized JCP allergens and discuss the impact of CRD and characterization of novel allergens on allergen-specific immunotherapy. © 2015 Japanese Society of Allergology.
Matsuda I.,Chiba Institute of Science |
Nittono H.,Hiroshima University |
Ogawa T.,Chiba Institute of Science
Psychophysiology | Year: 2013
The concealed information test (CIT) assesses an examinee's recognition of a crime-relevant item using physiological measures. However, a guilty examinee not only recognizes the crime-relevant item but also conceals the recognition intentionally. In this study, we attempted to identify the effect of concealing the recognition on event-related potentials and autonomic responses. After committing a mock theft of two items, 30 participants received two CITs: one for an item that they had to conceal, and the other for an item that they had disclosed. N2, P3, heart rate, skin conductance, and cutaneous blood flow differed between crime-relevant and irrelevant items in both CITs. In contrast, late positive potential and respiration differed between crime-relevant and irrelevant items only when the examinee needed to conceal. The former measures appear to be related to orienting process, whereas the latter to controlled process related to concealment. © 2013 Society for Psychophysiological Research.
Iwamoto T.,Hiroshima University |
Yokoyama T.,Okayama University of Science
Mechanics of Materials | Year: 2012
The split Hopkinson pressure bar (SHPB) technique has been used widely for the impact testing of materials in the strain-rate range from 10 2 to 10 4 s -1. However, some specific problems still remain mainly concerning the effects of radial inertia and end friction in a cylindrical specimen on the accurate determination of dynamic stress-strain curves of materials. In this study, the basic principle of the SHPB technique is revisited based on energy conservation and some modifications are made considering radial momentum conservation. It is pointed out that the radial inertia and end friction effects are coupled to each other in the SHPB specimen. Computational simulations using the commercial finite element (FE) code ABAQUS/Explicit ver. 6.8 are conducted to check the validity of the modifications for ductile pure aluminum specimens. Both rate-independent and rate-dependent models are adopted for the test material. Simulations are performed by varying two different control parameters: a friction coefficient between the specimen and the pressure bars and a slenderness ratio of the specimen (or thickness to diameter ratio). © 2012 Elsevier Ltd. All rights reserved.
Matsuoka L.,Hiroshima University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015
We obtained a simple theoretical unified parameter for the characterization of rotational population propagation of diatomic molecules in a periodic train of terahertz optical pulses around the condition of so-called quantum resonance. The parameter comprises the peak intensity and interval between the pulses, and the level energies of the initial and final rotational states of the molecule. Using the unified parameter, we can predict the upper and lower boundaries of probability localization on the rotational level network, including the effect of centrifugal distortion. The unified parameter was tentatively derived from an analytical expression obtained by performing rotating-wave approximation and spectral decomposition of the time-dependent Schrödinger equation under an assumption of time-order invariance. The validity of the parameter was confirmed by comparison with numerical simulations for isotope-selective rotational excitation of KCl molecules. © 2015 American Physical Society.
Tatsugami F.,Hiroshima University
Journal of Computer Assisted Tomography | Year: 2016
OBJECTIVE: Adaptive motion correction (AMC) is a new technique that can suppress blurring of the coronary arteries. We evaluated its effect on the image quality of coronary computed tomography angiography in patients with atrial fibrillation (AF). METHODS: Twenty-five patients with persistent AF underwent coronary computed tomography angiography. Axial image data sets were reconstructed with and without AMC and the image noise in the perivascular tissue of the coronary arteries was measured. Two radiologists visually evaluated the overall image quality of the coronary artery segment using a 4-point scale (1, uninterpretable; 4, good). RESULTS: The mean image noise in the perivascular tissue of the right, but not the left coronary artery, was reduced by AMC (43.8 vs 52.5 Hounsfield units; P < 0.01) and the mean image quality score for the right, but not the left coronary artery, was improved by AMC (3.01 vs 2.74; P < 0.01). The image quality scores in patients with a heart rate of 75 to 114 beats per minute tended to be improved by AMC (75–94 beats per minute: P = 0.06; 95–114 beats per minute: P < 0.01); in patients with a heart rate up to 74 or above 115 beats per minute, they were not improved (P = 0.46 and P = 0.13, respectively). CONCLUSIONS: Adaptive motion correction reduced motion artifacts and improved image quality of the right coronary artery in some patients with AF. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.
Gabriel A.A.,University of the Philippines at Diliman |
Gabriel A.A.,Hiroshima University
Food Control | Year: 2014
This study established the inactivation kinetic parameters of some pathogenic bacteria including Escherichia coli O157:H7, Salmonella enterica serotypes, and Listeria monocytogenes; and spoilage yeasts namely, Debaryomyces hansenii, Clavispora lusitaniae, Torulaspora delbrueckii, Pichia fermentans, and Saccharomyces cerevisiae in orange juice subjected to multi-frequency Dynashock power ultrasound treatment. All test organisms exhibited a biphasic inactivation behavior with a sigmoidal inactivation curve consisted of an initial inactivation lag, followed by logarithmic linear inactivation. Injury accumulation in the inactivation lag phase was established in acid-adapted bacteria. The time necessary to reduce initial inoculated populations by 5 log cycles (99.999%), T5D values, significantly increased with acid adaptation. The T5D of E.coli, S.enterica, and L.monocytogenes increased from 37.64, 36.87, and 34.59 respectively; to 54.72, 40.38, and 37.83min respectively after acid exposure. Temperature increase due to sensible heat propagation during ultrasound treatment decreased the resistance of the test bacteria. The cocktail of E.coli O157:H7 had significantly greater resistance towards ultrasound treatment (T5D=54.72min) than any of the individual strain (T5D=41.48-47.48min) in the mix. Similar results were found in the composited (T5D=60.02min) and individual species (T5D=20.31-59.04min). The results established in this work provide baseline information on microbial behavior in multi-frequency ultrasound-treated orange juice for establishment of pasteurization process schedules. © 2014 Elsevier Ltd.
Kato T.,Kyoto University |
Makoto Uemura,Hiroshima University
Publications of the Astronomical Society of Japan | Year: 2012
We introduced least absolute shrinkage and selection operator (Lasso) in obtaining periodic signals in unevenly spaced time-series data. A very simple formulation with the combination of a large set of sine and cosine functions has been shown to yield a very robust estimate; also, the peaks in the resultant power spectra were very sharp. We studied the response of Lasso to low signal-to-noise data, asymmetric signals and very closely separated multiple signals. When the length of the observation was sufficiently long, all of them were not serious obstacles to Lasso. We analyzed the 100-year visual observations of i Cep, and obtained a very accurate period of 5.366326(16) d. The error in the period estimation was several times smaller than in the phase dispersion minimization. We also modeled the historical data of R Sct, and obtained a reasonable fit to the data. The model, however, lost its predictive ability after the end of the interval used for modeling, which is probably a result of the chaotic nature of the pulsations of this star. We also provided a sample R code for making this analysis. © 2012 Astronomical Society of Japan.
Watanabe H.,Hiroshima University
Journal of Toxicologic Pathology | Year: 2010
This review concerns stem cells and their relation to intestinal metaplasia. When gastric regions of mice, Mongolian gerbils or several strains of rats were irradiated with a total dose of 20 Gy of X-rays given in two fractions, intestinal metaplasia was only induced in rats. In addition, it was greatly influenced by rat strain and sex. Alkaline phosphatase (ALP) positive metaplastic foci were increased by administration of ranitidine (H 2 receptor antagonist), crude stomach antigens or subtotal resection of the fundus and decreased by cysteamine (gastric acid secretion stimulator), histamine or removal of the submandibular glands. Recent studies have shown that Cdx2 transgenic mice with gastric achlorhydria develop intestinal metaplasia and that in men and animals, Helicobacter pylori (H. pyrlori) infection can cause intestinal metaplasias that are reversible on eradication. Our results combined with findings for H. pylori infection or eradication and transgenic mice suggest that an elevation in the pH of the gastric juice due to disappearance of parietal cells is one of the principal factors for development of reversible intestinal metaplasia. When different organs were transplanted into the stomach or duodenum, they were found to transdifferentiate into gastric or duodenal mucosae, respectively. Organ-specific stem cells in normal non-liver tissues (heart, kidney, brain and skin) also differentiate into hepatocytes when transplanted into an injured liver. Therefore, stem cells have a multipotential ability, transdifferentiating into different organs when transplanted into different environments. Finally, intestinal metaplasia has been found to possibly increase sensitivity to the induction of tumors by colon carcinogens of the 1,2- dimethylhydrazine (DMH), azoxymethane (AOM) or 2-amino-1-methyl-6-phenylimidazo[4.5-b]pyridine (PhIP) type. This carcinogenic process, however, may be relatively minor compared with the main gastric carcinogenesis process induced by N-methy1-N'-nitro-N-nitrosoguanidine (MMNG) or N-methylnitrosourea (MNU), which is not affected by the presence of intestinal metaplasia. The protocol used in these experiments may provide a new approach to help distinguish between developmental events associated with intestinal metaplasia and gastric tumors.
Kondo T.,Hiroshima University
Proceedings. Biological sciences / The Royal Society | Year: 2012
Livistona mariae is an endemic palm localized in arid central Australia. This species is separated by about 1000 km from its congener L. rigida, which grows distantly in the Roper River and Nicholson-Gregory River catchments in northern Australia. Such an isolated distribution of L. mariae has been assumed to have resulted from contraction of ancestral populations as Australia aridified from the Mid-Miocene (ca 15 Ma). To test this hypothesis at the population level, we examined the genetic relationships among 14 populations of L. mariae and L. rigida using eight nuclear microsatellite loci. Our population tree and Bayesian clustering revealed that these populations comprised two genetically distinct groups that did not correspond to the current classification at species rank, and L. mariae showed closest affinity with L. rigida from Roper River. Furthermore, coalescent divergence-time estimations suggested that the disjunction between the northern populations (within L. rigida) could have originated by intermittent colonization along an ancient river that has been drowned repeatedly by marine transgression. During that time, L. mariae populations could have been established by opportunistic immigrants from Roper River about 15 000 years ago, concurrently with the settlement of indigenous Australians in central Australia, who are thus plausible vectors. Thus, our results rule out the ancient relic hypothesis for the origin of L. mariae.
Haverkort M.W.,Max Planck Institute for Solid State Research |
Hollmann N.,University of Cologne |
Krug I.P.,Julich Research Center |
Tanaka A.,Hiroshima University
Physical Review B - Condensed Matter and Materials Physics | Year: 2010
A general symmetry analysis of the optical conductivity or scattering tensor is presented and used to rewrite the conductivity tensor as a sum of linear independent spectra multiplied by simple functions depending on the local magnetization direction. This allows one to describe the full, magnetization directional dependent, magneto-optical response of a system in arbitrary symmetry by only a few linear independent fundamental spectral functions. Using this formalism, we discuss the azimuthal dependence of the resonant x-ray diffracted intensity on magnetic Bragg reflections. We present several numerical examples at the transition metal L2,3 edge. From these numerical calculations, we can conclude that for realistic parameters several fundamental spectra, not present in spherical symmetry, become important and should not be neglected. Deviations from the standard analysis in spherical symmetry become large in cases where orbital order coexists with magnetic order, even if the orbital order is at a different q vector. In the extreme case of the layered cuprates, one finds that one is not sensitive to the projection of the magnetic moments onto the plane of the ordered dx2 - y2 hole. Not including the correct crystal symmetry can lead to incorrectly determined magnetic orientations and structures. © 2010 The American Physical Society.
Li T.,Hokkaido University |
Nishida K.,Hiroshima University |
Hiroyasu H.,Hiro Technology Brains Inc.
Fuel | Year: 2011
Spray atomization and evaporation play extremely important roles in mixture formation and combustion processes of direct injection (DI) gasoline engines. In this study, the fundamental characteristics of a swirl spray injected into a constant volume vessel are investigated by means of several laser diagnostic techniques including the laser diffraction-based method for droplet size distribution, the laser induced fluorescence-particle image velocimetry for velocity distributions of droplets and spray-induced ambient air flow, and the two-wavelength laser absorption-scattering technique for concentration distributions of liquid and vapor phases in the spray. The results show that the droplets at outer zone of the spray exhibit larger diameter than those at inner zone under both ambient pressures 0.1 and 0.4 MPa. While this can be partially attributed to the effect of spray-induced ambient air flow, the strength of ambient air flow become small when increasing the ambient pressure from 0.1 to 0.4 MPa, indicating the strong influence of spray dynamics on the droplet size distribution. In the evaporating spray, there are higher vapor concentrations near the spray axis than at peripheral zones. At 4.0 ms after start of injection, spray droplets almost completely evaporate under ambient temperature 500 K and pressure 1.0 MPa, but there are significantly amount of fuels with equivalence ratio below 0.5 in the spray. Reduction in ambient pressure promotes the air entrainment and droplet evaporation, but lowered ambient pressure results in more fuel vapor of equivalence ratio above 1.3 along the spray axis. © 2011 Elsevier Ltd. All rights reserved.
Takeuchi T.,Hiroshima University |
Takeuchi T.,Kyoto University
Behavioral Ecology and Sociobiology | Year: 2011
Male butterflies compete over mating territories via aerial interactions. It has often been suggested that flight performance, and thus flight-related traits, would play an important role in butterflies' contest resolution; however, most studies have not demonstrated a clear relationship between these traits and territory ownership in butterflies. Males of the satyrine butterfly Lethe diana compete over territories via linear chases, a behavior that is uncommon among butterflies: rather, contests of most butterfly species consist of circling flights. In the present study, some morphological and physiological traits of L. diana were compared between territory owners and intruders to search for traits correlated with resource holding power (RHP). Territory owners had higher flight-muscle ratio (FMR) and were heavier than intruders, indicating that flight performance plays a key role in their contest resolution. Contest duration was not affected by the owners' FMR or body mass, and thus I obtained no evidence supporting the hypothesis that contestants assess their relative RHP before making a decision to retreat. I speculate that the fact that these traits had an effect on territorial status in L. diana was a result of the characteristics of the contest behavior of this butterfly. During their contests, males L. diana fly faster in their linear flights than males of most other butterflies, which engage in slower circling flights. Therefore, males of L. diana probably need higher flight performance capabilities in order to win their contests. © 2011 Springer-Verlag.
Kato A.,University of Ryukyus |
Kato A.,Hiroshima University |
Baba M.,Marine Ecology Research Institute |
Suda S.,University of Ryukyus
Journal of Phycology | Year: 2011
The subfamily Mastophoroideae (Corallinaceae, Rhodophyta) is characterized by species possessing nongeniculate, uniporate tetrasporangial conceptacles without apical plugs, the presence of cell fusions, and the absence of secondary pit connections. However, molecular phylogenetic studies not including the type genus Mastophora indicated that the Mastophoroideae was polyphyletic. Our molecular phylogenetic analysis of the subfamily including the type genus using DNA sequences of SSU rDNA and plastid-encoded gene of PSII reaction center protein D1 (psbA) revealed that Mastophora formed a robust clade only with Metamastophora. The other mastophoroid genera were divided into six lineages within the family Corallinaceae. Five supported lineages-(i) Pneophyllum; (ii) Hydrolithon gardineri (Foslie) Verheij et Prud'homme, Hydrolithon onkodes (Heydr.) Penrose et Woelk., and Hydrolithon pachydermum (Foslie) J. C. Bailey, J. E. Gabel et Freshwater; (iii) Hydrolithon reinboldii (Weber Bosse et Foslie) Foslie; (iv) Spongites; and (v) Neogoniolithon-were clearly distinguished by the combination of characters including the presence or absence of palisade cells and trichocytes in large, tightly packed horizontal fields and features of tetrasporangial and spermatangial conceptacles. Therefore, we amend the Mastophoroideae to be limited to Mastophora and Metamastophora with a thin thallus with basal filaments comprised of palisade cells, tetrasporangial conceptacles formed by filaments peripheral to fertile areas, and spermatangia derived only from the floor of male conceptacles. This emendation supports Setchell's (1943) original definition of the Mastophoroideae as having thin thalli. We also propose the establishment of three new subfamilies, Hydrolithoideae subfam. nov. including Hydrolithon, Porolithoideae subfam. nov. including the resurrected genus Porolithon, and Neogoniolithoideae subfam. nov. including Neogoniolithon. Taxonomic revisions of Pneophyllum and Spongites were not made because we did not examine their type species. © 2011 Phycological Society of America.
Eguchi T.,Hiroshima University
Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C | Year: 2013
In this paper, we propose an efficient scheduling method for a job shop environment in which production capacity is adjustable by adding overtime in each machine of each production shift. The primal objective of scheduling is to meet due-dates of jobs and the secondary one is to minimize overtime. To achieve these two objectives efficiently, the schedule is searched to eliminate tardy jobs at first by allowing large overtime. Then the overtime is minimized. The method using the mixture of genetic algorithm and priority rule is applied for this scheduling. In this method, the characteristics of priority rules are the key for improving performance. In particular, when minimizing overtime after finding schedules without tardiness, it is important to maintain more individuals meeting due dates even after genetic operations are applied. For this purpose, we propose a scheduling method using the priority rules which are modified (CR+SPT) rule and ATC rule. Numerical experiments show the effectiveness of the proposed method. © 2013 The Japan Society of Mechanical Engineers.
Nakagawa K.,Hiroshima University
Dynamical Systems | Year: 2016
A multifractal rigidity is the phenomena that the coincidence with the two multifractal spectra implies more strong relation between the given two dynamical systems. For the dimension spectrum of a Bernoulli measure defined on a repeller of a piecewise linear Markov map, Barreira, Pesin and Schmeling proved that a rigidity holds if the repeller is modelled by the full shift of two symbols. It was an open problem whether this rigidity holds in the case of three or more symbols. We give a negative answer to this problem by constructing a counter-example and we show that our counter-example is the unique one in the case of three symbols. © 2016 Taylor & Francis
Tomaschitz R.,Hiroshima University
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2014
Dissipative tachyonic Cherenkov densities are derived and tested by performing a spectral fit to the . γ-ray flux of supernova remnant (SNR) RX J1713.7 - 3946, measured over five frequency decades up to 100 TeV. The manifestly covariant formalism of tachyonic Maxwell-Proca radiation fields is developed in the spacetime aether, starting with the complex Lagrangian coupled to dispersive and dissipative permeability tensors. The spectral energy and flux densities of the radiation field are extracted by time averaging, the energy conservation law is derived, and the energy dissipation caused by the complex frequency-dependent permeabilities of the aether is quantified. The tachyonic mass-square in the field equations gives rise to transversally/longitudinally propagating flux components, with differing attenuation lengths determined by the imaginary part of the transversal/longitudinal dispersion relation. The spectral fit is performed with the classical tachyonic Cherenkov flux radiated by the shell-shocked electron plasma of SNR RX J1713.7 - 3946, exhibiting subexponential spectral decay. © 2014 Elsevier B.V.
Shiono T.,Hiroshima University
Polymer Journal | Year: 2011
This article reviews the living homopolymerization and copolymerization of propene, 1-alkene and norbornene with ansa-dimethysilylene(fluorenyl)(amido) dimethyltitanium, Me2 Si(η3-C13 H 8)(η1-NtBu)TiMe2 and its derivatives, correlating the effects of cocatalysts, solvents, polymerization conditions and the substituents of the fluorenyl ligand with catalytic features, such as livingness, initiation efficiency, propagation rate, syndiospecificity and copolymerization ability. The synthesis of novel olefin block copolymers and their catalytic synthesis are also introduced using this living system. © The Society of Polymer Science, Japan (SPSJ) All rights reserved.
Namera A.,Hiroshima University |
Nakamoto A.,Forensic Science Laboratory |
Saito T.,Tokai University |
Miyazaki S.,GL Sciences Inc.
Journal of Separation Science | Year: 2011
Monolith was first used as a material for chromatographic separation two decades ago and solid-phase extraction over 10 years, and since then, separation science has undergone a dramatic change owing to advancements in analytical technology. Recently, monolith has been modified to suit various devices for the extraction and enrichment of analytes in any matrices of environmental, food, and biological analyses. This approach has contributed to miniaturization and automation for sample preparation, and it can reduce the time and cost requirements of sample preparation. Recently, numerous applications have been demonstrated for online and inline preconcentration coupled with monolith, and many kinds of devices have been designed and developed for offline devices. In this review, these applications and devices are listed and discussed in reference to other fields. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Asano K.,University of Tokyo |
Takahara F.,Osaka University |
Kusunose M.,Kwansei Gakuin University |
Toma K.,Osaka University |
Kakuwa J.,Hiroshima University
Astrophysical Journal | Year: 2014
The second-order Fermi acceleration (Fermi-II) driven by turbulence may be responsible for the electron acceleration in blazar jets. We test this model with time-dependent simulations. The hard electron spectrum predicted by the Fermi-II process agrees with the hard photon spectrum of 1ES 1101-232. For other blazars that show softer spectra, the Fermi-II model requires radial evolution of the electron injection rate and/or diffusion coefficient in the outflow. Such evolutions can yield a curved electron spectrum, which can reproduce the synchrotron spectrum of Mrk 421 from the radio to the X-ray regime. The photon spectrum in the GeV energy range of Mrk 421 is hard to fit with a synchrotron self-Compton model. However, if we introduce an external radio photon field with a luminosity of 4.9 × 1038 erg s-1, GeV photons are successfully produced via inverse Compton scattering. The temporal variability of the diffusion coefficient or injection rate causes flare emission. The observed synchronicity of X-ray and TeV flares implies a decrease of the magnetic field in the flaring source region. © 2014. The American Astronomical Society. All rights reserved..
Zhang J.Y.,Nagoya City University |
Ohsaki M.,Hiroshima University
Journal of the Mechanics and Physics of Solids | Year: 2012
This paper presents analytical conditions of self-equilibrium and super-stability for the regular truncated tetrahedral tensegrity structures, nodes of which have one-to-one correspondence to the tetrahedral group. These conditions are presented in terms of force densities, by investigating the block-diagonalized force density matrix. The block-diagonalized force density matrix, with independent sub-matrices lying on its leading diagonal, is derived by making use of the tetrahedral symmetry via group representation theory. The condition for self-equilibrium is found by enforcing the force density matrix to have the necessary number of nullities, which is four for three-dimensional structures. The condition for super-stability is further presented by guaranteeing positive semi-definiteness of the force density matrix. © 2012 Elsevier Ltd.
Uye S.-I.,Hiroshima University
Hydrobiologia | Year: 2011
Copepods, the most abundant planktonic metazoans, constitute an intermediate trophic position between phytoplankton and higher trophic-level animals such as fish and jellyfish. Fish and jellyfish are adversaries because they often compete for prey copepods and also can be prey of each other. The classical food chain represented by phytoplankton-copepod-fish is the main process leading to efficient and sustainable production of fish as human food. At present, more than 75% of world fish stocks are fully or over exploited. On the other hand, jellyfish populations have increased world-wide, particularly in waters under significant human influences. Two such cases are seen in East Asian waters, where massive blooms of moon jellyfish (Aurelia aurita s. l.) and giant jellyfish (Nemopilema nomurai) have repeatedly occurred in recent decades, causing severe damage to local fisheries. In this article, I will review the pivotal role of copepods in marine ecosystems, particularly in the Inland Sea of Japan, where the annual fish catch per unit area is among the world's highest. Then, I will describe an ongoing ecosystem shift from dominance by fish to dominance by jellyfish as a consequence of human forcing. Finally, I will propose to create "sato-umi", a coastal sea with high productivity and biodiversity with wise human interaction, where copepod production would most efficiently transforms into food for humans. © 2010 Springer Science+Business Media B.V.
Akiba K.-Y.,Hiroshima University
Heteroatom Chemistry | Year: 2011
The major studies of my research group in the University of Tokyo (1965-1980) and Hiroshima University (1980-2000) and some related research (2000-2010) are outlined briefly. The following themes are included mostly in chronological order: (1) phosphoranes and nitrosoimines, (2) synthetic work based on heteroaromatic cations and activation of imines, (3) bond switching at hypervalent sulfurane (10-S-3): energy of a hypervalent bond, (4) formation of the hypervalent bond, (5) edge inversion of antimony(III) and bismuth(III) compounds, (6) apicophilicity, pseudorotation, and ligand coupling, (7) freezing pseudorotation of phosphoranes and its effect, (8) hypervalent ate complexes of antimony and bismuth and their transition metal complexes, (9) hypervalent organotellurium compounds, (10) porphyrins of group 15 elements (phosphorus, arsenic, and antimony), and (11) synthesis and structure of hypervalent carbon species (10-C-5 and 12-C-6). © 2011 Wiley Periodicals, Inc.
Sogabe A.,Hiroshima University
Journal of Ethology | Year: 2011
The pipefish Corythoichthys haematopterus, which forms lifelong pair bonds and exhibits strict monogamy, performs a daily ritualized intrapair interaction, called the greeting. Cross-pairing experiments were performed to examine the capacity for partner recognition in C. haematopterus during the greeting. When pair members were released into an artificially constructed greeting arena, they exhibited typical greeting behavior immediately after contact. In contrast, when males and females from different pairs met, almost no displays were exchanged. These results strongly suggest that paired C. haematopterus can recognize their own partners, irrespective of the meeting location. © 2010 Japan Ethological Society and Springer.
Saeki M.,Hiroshima University
Proceedings of the American Control Conference | Year: 2012
Estimate of the gain characteristics of systems by using a transient response is essential for the development of our data-driven loop shaping method, and we have proposed an estimation method using a filterbank. Estimate of the l2 gain is also essential for model validation and the extension theorem gives the theoretical basis. In this paper, the relationship between our estimation method and the l2 gain estimation method based on the extension theorem is clarified, and a method for a proper setting of bandpass filter parameters is proposed. Further, the l2 gain estimates by using these methods are compared in accuracy, efficiency, and robustness against noise by numerical experiments. © 2012 AACC American Automatic Control Council).
Iwamoto H.,University of Helsinki |
Iwamoto H.,Hiroshima University |
Gao J.,University of Helsinki |
Koskela J.,University of Helsinki |
And 4 more authors.
European Respiratory Journal | Year: 2014
The pathophysiological features of chronic obstructive pulmonary disease (COPD)-asthma overlap are poorly understood and there has been no study of plasma or sputum biomarkers in overlap patients. In order to clarify the similarity and differences between overlap and COPD or asthma, we have investigated four potential biomarkers of COPD: surfactant protein A (SP-A), soluble receptor for advanced glycation end-products (sRAGE), myeloperoxidase (MPO) and neutrophil gelatinase-associated lipocalin (NGAL). SP-A and sRAGE are pneumocyte-derived markers. MPO and NGAL are neutrophil-derived molecules, but NGAL can also be expressed by respiratory epithelial cells. Plasma levels of SP-A and sRAGE and induced sputum levels of MPO and NGAL were measured by enzyme immunoassay/ELISA in 134 subjects: nonsmokers (n526), smokers (n523), asthma (n532), COPD (n539) and COPD-asthma overlap patients (n514). In patients with COPD-asthma overlap, sputum MPO and plasma SP-A were significantly elevated whereas plasma sRAGE levels were reduced compared with asthma patients. Only sputum NGAL was significantly elevated in COPD-asthma overlap compared with COPD (p50.00016) and could be used to differentiate patients with overlap from those with COPD. Increased induced sputum levels of NGAL might be a characteristic feature of overlap, suggesting enhanced neutrophilic airway inflammation and/or airway epithelial injury in COPD-asthma overlap. Copyright © ERS 2014.
Hofmann H.F.,Hiroshima University |
Hofmann H.F.,Chiyoda Corporation
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015
Quantum paradoxes show that quantum statistics can exceed the limits of positive joint probabilities for physical properties that cannot be measured jointly. It is therefore impossible to describe the relations between the different physical properties of a quantum system by assigning joint realities to their observable values. Instead, recent experimental results obtained by weak measurements suggest that nonclassical correlations could be expressed by complex valued quasiprobabilities, where the phases of the complex probabilities express the action of transformations between the noncommuting properties [H. F. Hofmann, New J. Phys. 13, 103009 (2011)NJOPFM1367-263010.1088/1367-2630/13/10/103009]. In these relations, negative probabilities necessarily emerge whenever the physical properties involved are related to each other by half-periodic transformations, since such transformations are characterized by action phases of π in their complex probabilities. It is therefore possible to trace the failure of realist assumptions back to a fundamental and universally valid relation between statistics and dynamics that associates half-periodic transformations with negative probabilities. © 2015 American Physical Society.
Yamamoto T.,Hiroshima University
Colloid and Polymer Science | Year: 2012
Soap-free emulsion polymerizations of aromatic vinyl monomers using 2,2'-azobis(2-methylpropionitrile) (AIBN) were investigated to clarify the origin of the negative charge of the synthesized particles. It was found that the zeta potential and size of the particles synthesized by soapfree emulsion polymerization using AIBN had a strong relationship with the pi electron cloud density in the aromatic vinyl monomer used in the polymerization. The effect of the position of the substituent atom in the phenyl ring on the synthesized particle properties was small. © Springer-Verlag 2012.
Tanabe S.,Hiroshima University
Current Pharmaceutical Design | Year: 2012
The intestinal epithelial barrier is indispensable to our immune system. Defects in this barrier function have been observed in intestinal disorders such as inflammatory bowel diseases, food allergies, and celiac diseases. Therefore, the modulation of the barrier function is currently viewed as a potentially positive pharmacological outcome. This review describes a unique peptide, Asn-Pro-Trp- Asp-Gln (NPWDQ), which can finely adjust the intestinal barrier. It is obtained by the hydrolysis of casein, a major milk protein, and considerably inhibits the permeation of ovalbumin, one of the food allergens, in Caco-2, a human intestinal cell line. Using DNA microarray, we observed that NPWDQ only up-regulated expression of the occludin gene, whereas the levels of other genes, such as those of the claudin and zonula occludens families, remained unchanged. Increased protein expression of occludin was also observed. The fact that milk-derived peptide(s) can enhance intestinal barrier function gives a new significance to lactation because it plays an important role in promoting the maturation of the intestinal barrier. In this context, it is highly probable and worthy of considerable attention that various bioactive peptides with this type of activity are yet to be observed in the bovine and/or human casein sequence. Moreover, milkderived peptides could be considered as potential candidates for the prevention of certain intestinal disorders. © 2012 Bentham Science Publishers.
Okazawa S.,Hiroshima University
International Journal of Non-Linear Mechanics | Year: 2010
Necking localization is common unstable behavior in ductile solids. This paper describes the unified necking localization mechanism. After describing one-dimensional instability problem, general material and structural instability criteria are formulated and the formulation is validated by non-linear finite element analysis. The trigger of necking localization is structural bifurcation and the behavior from a uniformly deformed state to ultimate localization just before fracture is continuous structural instability. © 2009 Elsevier Ltd. All rights reserved.
El-Araby E.E.,Suez Canal University |
Yorino N.,Hiroshima University
International Journal of Electrical Power and Energy Systems | Year: 2010
This paper develops a new market-based technique for acquiring VAR ancillary service in the electricity market. The main objective of the developed market is to enable transmission operator "TO" to procure VAR service in a long term contract from the critical VAR providers that satisfy minimum VAR service payment while maintaining system security. Reactive power control problem for voltage stability is introduced into the VAR market problem in an explicit manner for normal and emergency states. An integration of particle swarm optimization "PSO" is presented with successive linear programming "SLP" for dealing with the VAR ancillary service problem. The problem is formulated as a large-scale nonlinear constrained optimization problem with a non-differentiable objective function representing VAR payment and operational costs. This type of problem is hard to be treated straightforwardly by the classical optimization methods. Therefore, we propose here a two-layer hybrid PSO/SLP approach, which is suited for carrying out the difficulties associated with non-differentiable and discontinuous objective functions. The proposed method has been examined on the standard IEEE 57 bus-system and compared with GA/SLP method to demonstrate its capability. © 2009 Elsevier Ltd. All rights reserved.
Ikeda T.,Hiroshima University
Journal of Computational and Nonlinear Dynamics | Year: 2010
The characteristics of two, three, and four nonlinear vibration absorbers or nonlinear tuned mass dampers (NTMDs) attached to a structure under harmonic excitation are investigated. The frequency response curves are theoretically determined using van der Pol's method. When the parameters of the absorbers are equal, it is found from the theoretical analysis that pitchfork bifurcations may occur on the part of the response curves, which are unstable in the multi-absorber systems, but are stable in a system with one NTMD. Multivalued steady-state solutions, such as three steady-state solutions for a dual-absorber system with different amplitudes, five steady-state solutions for a tripleabsorber system, and seven steady-state solutions for a quadruple-absorber system, appear near bifurcation points. The NTMDs behave in that one of them vibrates at high amplitudes while the others vibrate at low amplitudes, even if the dimensions of the NTMDs are identical. Namely, "localization phenomenon" or "mode localization" occurs. After the pitchfork bifurcation, Hopf bifurcations may occur depending on the values of the system parameters, and amplitude- and phase-modulated motions, including chaotic vibrations, appear after the Hopf bifurcation when the excitation frequency decreases. Lyapunov exponents are numerically calculated to prove the occurrence of chaotic vibrations. Bifurcation sets are also calculated to investigate the influence of the system parameters on the response of the systems. © 2010 by ASME.
Nakasa T.,Hiroshima University
Clinical calcium | Year: 2011
Articular cartilage has the poor capacity for cartilage regeneration, which lead to develop osteoarthritis when cartilage injury occurs. Autologous chondrocyte implantation using three dimensional culture within atelocollagen gel has obtained good clinical results for articular cartilage injury. However, there are two concerns associated with this technique : the number of harvested chondrocyte is limited and arthrotomy is required for implantation of tissue-engineered cartilage. To improve the cell-based articular cartilage treatment, the use of other cell source such as mesenchymal stem cells, and development of less invasive and more efficient cell delivery system should be needed. Translational research will has more and more important implication for clinical application of articular cartilage repair.
Uchiyama S.,Hiroshima University
Physica A: Statistical Mechanics and its Applications | Year: 2012
We consider a neural network of StuartLandau oscillators as an associative memory. This oscillator network with N elements is a system of an N-dimensional differential equation, works as an attractor neural network, and is expected to have no Lyapunov functions. Therefore, the technique of equilibrium statistical physics is not applicable to the study of this system in the thermodynamic limit. However, the simplicity of this system allows us to extend statistical neurodynamics [S. Amari, K. Maginu, Neural Netw. 1 (1988) 6373], which was originally developed to analyse the discrete time evolution of the Hopfield model, into the version for continuous time evolution. We have developed and attempted to apply this method in the analysis of the phase transition of our model network. © 2011 Elsevier B.V. All rights reserved.
Kamei S.,Hiroshima University |
Kakugawa H.,Osaka University
Theoretical Computer Science | Year: 2012
In wireless ad hoc or sensor networks, a connected dominating set (CDS) is useful as the virtual backbone because there is no fixed infrastructure or centralized management. Additionally, in such networks, transient faults and topology changes occur frequently. A self-stabilizing system tolerates any kind and any finite number of transient faults, and does not need any initialization. An ordinary self-stabilizing algorithm has no safety guarantee and requires that the network remains static while converging to a legitimate configuration. Safe converging self-stabilization is one extension of self-stabilization. The safe convergence property guarantees that the system quickly converges to a safe configuration, and then, it moves to an optimal configuration without breaking safety. In this paper, we propose a self-stabilizing fully distributed 6-approximation algorithm with safe convergence for the minimum CDS in the networks modeled by unit disk graphs. © 2011 Elsevier B.V. All rights reserved.
Ikeda T.,Japan National Institute of Advanced Industrial Science and Technology |
Kayamori S.,Japan National Institute of Advanced Industrial Science and Technology |
Oumi Y.,Hiroshima University |
Mizukami F.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Physical Chemistry C | Year: 2010
Four kinds of Si-atom pillared lamellar silicates (APZ-1-APZ-4) were prepared by thermal acid treatment in an autoclave at 443 K for 1-24 h using aqueous HCl. Layered silicates PLS-1, PLS-3, PLS-4, and PREFER, which consist of ferrierite layer sheets, could be converted into new open-framework microporous materials by pillaring the interlayers with SiO2(-OH)2 fragments. The fragments probably originated from the collapse of the crystalline structure, and interlayer silylation occurred with the migration of the fragments (dissolution-condensation). The four APZ crystal structures were investigated by means of powder X-ray diffraction, revealing topotactic microporous structures that derived from each original layered silicate. APZ-2 and APZ-4 have the large pore openings of a 12-membered ring, whereas APZ-1 and APZ-3 have the slightly smaller pore openings of a 10-membered ring. All the APZs are hydrophilic to approximately the same degree as the common hydrophilic zeolite, owing to hydroxyl groups of the Si atom pillar or the terminal silanols in the interlayer. Thus, large numbers of water molecules are adsorbed in the micropores. 29Si MAS NMR spectra showed Q2, Q3, and Q 4 resonance peaks, whose Q2 signal indicated silanol groups of the Si atom pillar. All the APZ crystals showed high thermal stability and did not collapse upon heating to at least 873 K. © 2010 American Chemical Society.
Matsuda I.,Chiba Institute of Science |
Nittono H.,Hiroshima University
Clinical Neurophysiology | Year: 2015
Objective: The interaction between affective and cognitive processes has been examined using the late positive potential (LPP) component of the event-related brain potential. The LPP is elicited not only by affective stimuli but also by nonaffective stimuli that require effortful cognitive processing. However, it is unclear whether these LPPs are equivalent. The present study decomposed the LPP into subcomponents that responded differently to affective content and cognitive demands. Methods: The participants (N= 21) performed four types of revised oddball tasks, in which one affective and five nonaffective pictures were presented. For one of the nonaffective pictures, different cognitive demands were loaded: viewing the display, updating a count, updating two different items, or concealing knowledge of the picture. Results: A temporal-spatial principal component analysis revealed two major subcomponents of the LPP. The central-parietal subcomponent was elicited by affective stimuli, whereas the occipital subcomponent was elicited by nonaffective stimuli with cognitive demands in the two-item updating and concealment conditions. Conclusions: The results suggest that the central-parietal dominant LPP may reflect motivated attentional processing, whereas the occipital dominant LPP may reflect effortful controlled processing. Significance: Dealing with these two LPP subcomponents separately may be useful for examining the interaction between affective and cognitive processing of stimuli. © 2014 International Federation of Clinical Neurophysiology.
Nakata M.,Japan National Institute of Advanced Industrial Science and Technology |
Nakata M.,Hiroshima University |
Mitsuda N.,Japan National Institute of Advanced Industrial Science and Technology |
Herde M.,Michigan State University |
And 6 more authors.
Plant Cell | Year: 2013
Jasmonates (JAs) are plant hormones that regulate the balance between plant growth and responses to biotic and abiotic stresses. Although recent studies have uncovered the mechanisms for JA-induced responses in Arabidopsis thaliana, the mechanisms by which plants attenuate the JA-induced responses remain elusive. Here, we report that a basic helix-loophelix- type transcription factor, ABA-INDUCIBLE BHLH-TYPE TRANSCRIPTION FACTOR/JA-ASSOCIATED MYC2-LIKE1 (JAM1), acts as a transcriptional repressor and negatively regulates JA signaling. Gain-of-function transgenic plants expressing the chimeric repressor for JAM1 exhibited substantial reduction of JA responses, including JA-induced inhibition of root growth, accumulation of anthocyanin, and male fertility. These plants were also compromised in resistance to attack by the insect herbivore Spodoptera exigua. Conversely, jam1 loss-of-function mutants showed enhanced JA responsiveness, including increased resistance to insect attack. JAM1 and MYC2 competitively bind to the target sequence of MYC2, which likely provides the mechanism for negative regulation of JA signaling and suppression of MYC2 functions by JAM1. These results indicate that JAM1 negatively regulates JA signaling, thereby playing a pivotal role in fine-tuning of JA-mediated stress responses and plant growth. © 2013 American Society of Plant Biologists. All rights reserved.
Arakawa K.,Hiroshima University
Bioscience, Biotechnology and Biochemistry | Year: 2014
We extensively analyzed the giant linear plasmid pSLA2-L in Streptomyces rochei 7434AN4, a producer of two structurally unrelated polyketide antibiotics, lankacidin and lankamycin. It was found that amine oxidase LkcE oxidizes an acyclic amine to an imine, which is in turn converted to the 17-membered carbocyclic lankacidin. Heterologous expression and translational fusion experiments indicated the modular-iterative mixed polyketide biosynthesis of lankacidin. Concerning to lankamycin biosynthesis, starter unit biosynthesis and the post-PKS modification pathway were elucidated by feeding and gene inactivation experiments. It was shown that pSLA2-L contains many regulatory genes, which constitute the signaling molecule/receptor system for antibiotic production and morphological differentiation in this strain. Two signaling molecules, SRB1 and SRB2, that induce production of lankacidin and lankamycin were further isolated and their structures were elucidated. Each contains a 2,3-disubstituted butenolide skeleton, and the stereochemistry at C-1′ position is crucial for inducing activity. © 2014 Japan Society for Bioscience, Biotechnology, and Agrochemistry.
Imai S.,Hiroshima National College of Maritime Technology |
Yamamoto T.,Hiroshima University
International Journal of Advanced Mechatronic Systems | Year: 2012
Almost real-world plants are represented by non-linear systems. Therefore, it is important to consider PID control schemes to cope with such systems. In this paper, a PID control method for non-linear systems is newly proposed. Some local linear models on typical equilibrium points are first designed, followed by linear PID controllers corresponding to these models. The distances between the query and these local models are calculated, and the weights are computed in proportion to the distances. These weights are put for local PID controllers, and the PID controller corresponding to the query can be designed. According to the proposed scheme, the good PID control performance can be easily obtained. The effectiveness of the PID control scheme is illustrated by some simulation examples and experiment. © 2012 Inderscience Enterprises Ltd.
Kavitha M.S.,Hiroshima University
Journal of investigative and clinical dentistry | Year: 2012
To develop a computer-aided diagnosis system to continuously measure mandibular inferior cortical width on dental panoramic radiographs and evaluate the system's efficacy in identifying postmenopausal women with low-skeletal bone mineral density. Mandibular inferior cortical width was continuously measured by enhancing the original X-ray image, determining cortical boundaries, and evaluating all distances between the upper and lower boundaries in the region of interest. The system's efficacy in identifying osteoporosis at the lumbar spine and the femoral neck was evaluated for 100 women (≥50 years): 50 in the development of the tool and 50 in its validation. The sensitivity and specificity of the cortical measurements for identifying the development patients were 90% (95% confidence interval shown in parentheses) (63.0-87.0) in women with low spinal bone mineral density, and 81.8% (70.1-91.8) and 69.2% (56.2-81.8) in those with low femoral bone mineral density, respectively. Corresponding values in the validation patients were 93.3% (85.9-100) and 82.9% (71.4-92.7) at the lumbar spine, and 92.3% (84.5-99.5) and 75.7% (63.0-87.0) at the femoral neck, respectively. Our new computer-aided diagnosis system is a useful procedure in triage screening for osteoporosis. © 2011 Blackwell Publishing Asia Pty Ltd.
Morita K.,Hiroshima University
Theoretical Computer Science | Year: 2011
In this paper, we investigate how 1-D reversible cellular automata (RCAs) can simulate reversible Turing machines (RTMs) and cyclic tag systems (CTSs). A CTS is a universal string rewriting system proposed by M. Cook. First, we show that for any m-state n-symbol RTM there is a 1-D 2-neighbor RCA with a number of states less than (m+2n+1)(m+n+1) that simulates it. It improves past results both in the number of states and in the neighborhood size. Second, we study the problem of finding a 1-D RCA with a small number of states that can simulate any CTS. So far, a 30-state RCA that can simulate any CTS and works on ultimately periodic infinite configurations has been given by K. Morita. Here, we show there is a 24-state 2-neighbor RCA with this property. © 2011 Elsevier B.V. All rights reserved.
Hisatome T.,Chugoku Rosai Hospital |
Doi H.,Hiroshima University
Journal of Orthopaedic Science | Year: 2011
Background The purpose of this investigation is to determine the optimum position of the prosthesis in total hip arthroplasty for reducing neck impingement using a mathematical formula. Methods We calculated the cup inclination, cup anteversion, and stem antetorsion in cases with various sizes of femoral head (28, 32, 36, and 44 mm in diameter) to fulfill severe range of motion criteria: (1) flexion more than 120°, (2) extension more than 30°, (3) internal rotation at 90° flexion more than 60°, and (4)external rotation at neutral more than 40°. Results When the areas to fulfill the severe range of motion criteria were compared by femoral head diameter, the area for 28 mmwas extremelysmall relative to those of 32, 36, and 44 mm. Theoretically, the optimum position of theprosthesis in total hip arthroplasty without neck impingement should be oriented at a cup inclination of 45° combined with the cup anteversion and stem antetorsion so that thesum of the cup anteversion plus 0.7 times the stem antetorsion equals 42° with a head diameter more than 32 mm. This study also recommends the optimum position of the prosthesis as 45° cup inclination, 25° cup anteversion, and 25° stem antetorsion when the surgeon can choose a freely adjustablemodular stem system. However, this theory assumes that the pelvic inclination has no changes caused by aging and can be validated in the lying, sitting, and standing positions. Conclusions The prosthesis in total hip arthroplastywithout neck impingement should be oriented at a cup inclination of 45° combined with cup anteversion and stem antetorsion determined by the formula: cup anteversion + 0.79 × stem antetorsion = 42°. A range of acceptable positions would be more helpful and realistic to a surgeon trying to ensure adequate prosthesis positions. © The Japanese Orthopaedic Association 2011.
Kato K.,Hiroshima Institute of Technology |
Sakawa M.,Hiroshima University
Soft Computing | Year: 2011
In this paper, we focus on multiobjective linear programming problems involving random variable coefficients in objective functions and constraints. Using the concept of chance constrained conditions, such multiobjective stochastic linear programming problems are transformed into deterministic ones based on the variance minimization model under expectation constraints. After introducing fuzzy goals to reflect the ambiguity of the decision maker's judgements for objective functions, we propose an interactive fuzzy satisficing method to derive a satisficing solution for them as a fusion of the stochastic programming and the fuzzy one. The application of the proposed method to an illustrative numerical example shows its usefulness. © 2010 Springer-Verlag.
Hinamoto T.,Hiroshima University
Multidimensional Systems and Signal Processing | Year: 2011
Is sparsity an issue in 2-D digital filter design problems to explore and why is it important? How a 2-D filter can be designed to retain a desired coefficient sparsity for efficient implementation while achieving best possible performance subject to that sparsity constraint? These are the focus of this paper in which we present a two-phase design method for 2-D FIR digital filters in two most common design settings, namely, the least squares and minimax designs. Simulation studies are presented to illustrate each phase of the proposed design method and to evaluate the performance of the filters designed. © 2010 Springer Science+Business Media, LLC.
Shimahara H.,Hiroshima University
Journal of the Physical Society of Japan | Year: 2014
The spin susceptibility of noncentrosymmetric superconductors is studied when the gap function has line nodes. As examples, d-wave states, where the gap function has an additional odd-parity phase factor, are examined. The curve of the spin susceptibility X(T) is upward convex when all line nodes are parallel to the magnetic field, while it is downward convex in the other d-wave states and an s-wave state. For polycrystalline powder samples, the temperature dependences of X(T) are predicted by assuming three explicit conditions of the powder particles. The results are compared with the experimental data of the Knight shift observed in Li2Pt3B and Li2Pd 3B. © 2014 The Physical Society of Japan.
Enami Y.,Kochi University of Technology |
Kayaba Y.,Hiroshima University |
Luo J.,University of Washington |
Jen A.K.-Y.,University of Washington
Optics Express | Year: 2014
We report the efficient poling of an electro-optic (EO) polymer in a hybrid TiO2/electro-optic polymer multilayer waveguide modulator on mesoporous sol-gel silica cladding. The mesoporous sol-gel silica has nanometer-sized pores and a low refractive index of 1.24, which improves mode confinement in the 400-nm-thick EO polymer film in the modulators and prevents optical absorption from the lower Au electrode, thereby resulting in a lower half-wave voltage of the modulators. The half-wave voltage (Vπ) of the hybrid modulator fabricated on the mesoporous sol-gel silica cladding is 6.0 V for an electrode length (Lℓ) of 5 mm at a wavelength of 1550 nm (Vπℓ product of 3.0 V·cm) using a low-index guest-host EO polymer (in-device EO coefficient of 75 pm/V). © 2014 Optical Society of America.
Takahashi M.,Hiroshima University
International journal of phytoremediation | Year: 2012
Production of novel mutants with a high ability to mitigate pollutants is important for phytoremediation. We investigated the use of ion beam irradiation to produce mutants of Ficus pumila L. with an improved ability to mitigate atmospheric nitrogen dioxide (NO2). More than 25,000 shoot explants were irradiated with an ion beam (12C5+, 12C6+, or 4He2+), from which 263 independent plant lines were obtained. The plants were analyzed for NO2 uptake by fumigation with 1 ppm 15N-labeled NO2 for 8 h in light, followed by mass spectrometric analysis. The mean NO2 uptake values of each of the 263 lines differed over a 110-fold range. Propagation was attempted using cuttings from 44 lines showing the greatest NO2 uptake; in total, 15 lines were propagated. Two of the 15 lines showed a mean NO2 uptake 1.7- to 1.8-fold greater than that of the wild-type. This increase in NO2 uptake was heritable in both lines; their progenies showed a significantly greater ability to take up and assimilate NO2 than did the wild-type. RAPD analysis demonstrated DNA variation between the progeny plants and the wild type, suggesting that the progeny were true mutants. These mutants of F. pumila may prove useful in mitigating atmospheric NO2.
Fujita S.,Hiroshima University
IEEE Transactions on Computers | Year: 2011
In branch-and-bound (B&B) schemes for solving a minimization problem, a better lower bound could prune many meaningless branches which do not lead to an optimum solution. In this paper, we propose several techniques to refine the lower bound on the makespan in the multiprocessor scheduling problem (MSP). The key idea of our proposed method is to combine an efficient quadratic-time algorithm for calculating the Fernndez's bound, which is known as the best lower bounding technique proposed in the literature with two improvements based on the notions of binary search and recursion. The proposed method was implemented as a part of a B&B algorithm for solving MSP, and was evaluated experimentally. The result of experiments indicates that the proposed method certainly improves the performance of the underlying B&B scheme. In particular, we found that it improves solutions generated by conventional heuristic schemes for more than 20 percent of randomly generated instances, and for more than 80 percent of instances, it could provide a certification of optimality of the resulting solutions, even when the execution time of the B&B scheme is limited by one minute. © 2011 IEEE.
Makabe R.,Hiroshima University |
Tanimura A.,Mie University |
Fukuchi M.,Japan National Institute of Polar Research
Journal of Plankton Research | Year: 2012
Mesozooplankton abundance and species composition in the upper 200 m at seven sites in Lützow-Holm Bay, Antarctica, were compared using plankton nets with 60, 100 or 330 μm mesh during the austral summer of 2007-2008. While the collection efficiency of the 330 μm mesh was low, ranging from 2.0 to 5.6%, owing to the significant underestimation of small copepod species, no significant underestimation of abundance was found using the 100 μm mesh, except for copepod nauplii. © 2012 The Author. Published by Oxford University Press. All rights reserved.
Matsukawa T.,Tokyo University of Science |
Kurita T.,Hiroshima University
Pattern Recognition | Year: 2012
This paper presents a novel image representation method for generic object recognition by using higher-order local autocorrelations on posterior probability images. The proposed method is an extension of the bag-of-features approach to posterior probability images. The standard bag-of-features approach is approximately thought of as a method that classifies an image to a category whose sum of posterior probabilities on a posterior probability image is maximum. However, by using local autocorrelations of posterior probability images, the proposed method extracts richer information than the standard bag-of-features. Experimental results reveal that the proposed method exhibits higher classification performances than the standard bag-of-features method. © 2011 Elsevier Ltd. All rights reserved.
Tajima T.,Hiroshima University
AMB Express | Year: 2013
Most whole cell biocatalysts have some problems with yields and productivities because of various metabolites produced as byproducts and limitations of substrate uptake. We propose a psychrophile-based simple biocatalyst for efficient bio-production using mesophilic enzymes expressed in psychrophilic Shewanella livingstonensis Ac10 cells whose basic metabolism was inactivated by heat treatment. The 45°C heat-treated cells expressing lacZ showed maximum beta-galactosidase activity as well as chloroform/SDS-treated cells to increase membrane permeability. The fluorescent dye 5-cyano-2,3-ditolyl-tetrazolium chloride staining indicated that most basic metabolism of Ac10 was lost by heat treatment at 45°C for 10 min. The simple biocatalyst was applied for 3-HPA production by using Klebsiella pneumoniae dhaB genes. 3-HPA was stoichiometrically produced with the complete consumption of glycerol at a high production rate of 8.85 mmol 3-HPA/g dry cell/h. The amount of 3-HPA production increased by increasing the concentrations of biocatalyst and glycerol. Furthermore, it could convert biodiesel-derived crude glycerol to 3-HPA. © 2013 Tajima et al.
Yamakage A.,Tohoku University |
Nomura K.,RIKEN |
Imura K.-I.,Hiroshima University |
Kuramoto Y.,Tohoku University
Journal of the Physical Society of Japan | Year: 2011
Effects of disorder on two-dimensional ℤ2 topological insulator are studied numerically by the transfer matrix method. Based on the scaling analysis, the phase diagram is derived for a model of HgTe quantum well as a function of disorder strength and magnitude of the energy gap. In the presence of sz non-conserving spin-orbit coupling, a finite metallic region is found that partitions the two topologically distinct insulating phases. As disorder increases, a narrow-gap topologically trivial insulator undergoes a series of transitions; first to metal, second to topological insulator, third to metal, and finally back to trivial insulator. We show that this multiple transition is a consequence of two disorder effects; renormalization of the band gap, and Anderson localization. The metallic region found in the scaling analysis corresponds roughly to the region of finite density of states at the Fermi level evaluated in the self-consistent Born approximation. ©2011 The Physical Society of Japan.
Caux J.-S.,University of Amsterdam |
Konno H.,Hiroshima University |
Sorrell M.,University of Melbourne |
Weston R.,Heriot - Watt University
Physical Review Letters | Year: 2011
We consider the effects of interactions on spinon excitations in Heisenberg spin-1/2 chains. We compute the exact two-spinon part of the longitudinal structure factor of the infinite chain in zero field for all values of anisotropy in the gapless antiferromagnetic regime, via an exact algebraic approach. Our results allow us to quantitatively describe the behavior of these fundamental excitations throughout the observable continuum, for cases ranging from free to fully coupled chains, thereby explicitly mapping the effects of "turning on the interactions" in a strongly correlated system. © 2011 American Physical Society.
Tanaka Y.,Tezukayama University |
Sekiya H.,Hiroshima University
Research Quarterly for Exercise and Sport | Year: 2010
We investigated changes in movement kinematics and attentional focus when, expert and novice golfers performed a golfputting task under pressure. Six male professional golfers and five male novice golfers performed, 100 acquisition trials, followed by 10 trials in the pressure condition with a perforniance-contingent cash reward and small audience. After the 10 trials in the pressure condition, participants answered a questionnaire concerning attentional focus during both types of trial., including such aspects as conscious control of movements and the effects of distraction. A pressure manipulation clieck revealed a modest increase in physiological arousal, in that heart rate increased by about 10 bpni although state anxiety did not, increase. A two-dimensional analysis of movement kinematics revealed that the amplitudes of arm and club movements decreased on the backswing in the pressure condition. Arm and club movement speed decreased on the foreswing in both experts and novices. Furthermore, neither experts nor novices changed their attentional focus in tlie pressure condition. Wfiereas pretdous studies of "choking under pressure"focused on attentional changes, the kinematic changes found in the present study were possibly caused by the influences of strategy modification and/or emotional response. Choking phenomena can be explained by attentional changes, along with the influences of strategy modification and/or emotional response underpressure. © 2010 by the American Alliance for Health, Physical Education, Recreation and Dance.
Enami Y.,Hiroshima University |
Tsuchiya K.,University of Fukui |
Suye S.,University of Fukui
Applied Physics Letters | Year: 2011
In this letter, the authors report the real-time detection of an organophosphorus compound using a sol-gel silica planar waveguide doped with a green fluorescent protein and an organophosphorus hydrolase on a yeast-cell surface display. The waveguide was pumped at 488 nm, and it emitted green fluorescence at the far field. The green fluorescent light at 550 nm changed by 50% from the original power 1 min after application of the organophosphorus compound. The results enable the real-time detection of sarin and other biochemicals by using an in-line fiber sensor network. © 2011 American Institute of Physics.
Satoh S.,Hiroshima University |
Fujimoto K.,Kyoto University
IEEE Transactions on Automatic Control | Year: 2013
This paper introduces Stochastic Port-Hamiltonian Systems (SPHS's), whose dynamics are described by Itô stochastic differential equations. SPHS's are extension of the deterministic port-Hamiltonian systems which are used to express various passive systems. First, we show a necessary and sufficient condition to preserve the stochastic port-Hamiltonian structure of the system under a class of coordinate transformations. Second, we derive a condition for the system to be stochastic passive. Third, we equip Stochastic Generalized Canonical Transformations (SGCT's), which are pairs of coordinate and feedback transformations preserving the stochastic port-Hamiltonian structure. Finally, we propose a stochastic stabilization framework based on stochastic passivity and SGCT's. © 2012 IEEE.
Mukaidani H.,Hiroshima University
IET Control Theory and Applications | Year: 2011
In this study, the author discusses a Pareto strategy implemented via state and static output feedback for a class of weakly coupled large-scale discrete-time stochastic systems with state- and control-dependent noise. The asymptotic structure along with the uniqueness and positive semi-definiteness of the solutions of cross-coupled non-linear matrix equations (CNMEs) is newly established via the implicit function theorem. The main contribution of this study is the proposal of a parameter-independent local state and static output feedback Pareto strategy. Moreover, a computational approach for solving the CNMEs is also considered if the information about the small parameter is available. Particularly, a new iterative algorithm based on the linear matrix inequality is established to design a Pareto strategy. Finally, in order to demonstrate the effectiveness of the proposed design method, a numerical example is provided for prac