Hiroshima, Japan
Hiroshima, Japan

Hiroshima University , in the Japanese cities of Higashihiroshima and Hiroshima, was established 1929 by the merger of a number of national educational institutions. Wikipedia.

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Chugoku Electric Power Co., Hiroshima University and Toyo Koatsu Co. | Date: 2014-03-05

A gasification apparatus heats and pressurizes a gasification feedstock to bring the gasification feedstock into a supercritical state, and performs decomposition-treatment on the gasification feedstock to obtain fuel gas. The gasification apparatus includes a heat exchanger, a gas-liquid separator, and a synthesizer. The heat exchanger introduces the gasification feedstock into a low-temperature-side flow channel and introduces treated fluid in a supercritical state into a high-temperature-side flow channel, so that heat exchange is performed between the gasification feedstock and the treated fluid. The gas-liquid separator extracts, from the high-temperature-side flow channel, the treated fluid that has been in a subcritical state due to heat exchange, performs gas-liquid separation on the treated fluid, and returns a separated liquid to the high-temperature-side flow channel. The synthesizer synthesizes a liquid fuel from fuel gas separated by the gas-liquid separator.

Chugoku Electric Power Co., Hiroshima University and Toyo Koatsu Co. | Date: 2014-03-05

A gasification apparatus heats and pressurizes a gasification feedstock to bring the gasification feedstock into a supercritical state, and performs decomposition-treatment on the gasification feedstock to obtain fuel gas. The gasification apparatus includes a heat exchanger, a gas-liquid separator, and a turbine. The heat exchanger introduces the gasification feedstock into a low-temperature-side flow channel and introduces treated fluid in a supercritical state into a high-temperature-side flow channel, so that heat exchange is performed between the gasification feedstock and the treated fluid. The gas-liquid separator extracts, from the high-temperature-side flow channel, the treated fluid that has been in a subcritical state due to heat exchange, performs gas-liquid separation on the treated fluid, and returns a separated liquid to the high-temperature-side flow channel. The turbine is powered by fuel gas separated by the gas-liquid separator.

Hiroshima University | Date: 2016-08-23

An object of the present invention is to provide a method of detecting a nucleic acid binding protein and a method of screening for a binding inhibitor or promoter for a nucleic acid binding protein. According to the present invention, there is provided a method of detecting binding between a nucleic acid and a nucleic acid binding protein, comprising determining the degree of structural change in a nucleic acid complex having at least two nucleic acid duplex moieties.

Chugoku Electric Power Co., Hiroshima University and Toyo Koatsu Co. | Date: 2014-03-05

A gasification system includes a countercurrent type heat exchanger that includes a low-temperature side flow channel through which a gasification feedstock flows, and a high-temperature side flow channel to which treated water in a supercritical state is introduced. The treated water raises a temperature of the gasification feedstock by exchanging heat with the gasification feedstock. The system further includes a reactor that gasifies the gasification feedstock, whose temperature has been raised by the countercurrent type heat exchanger, by heating and pressurizing the gasification feedstock to be in a supercritical state. The reactor discharges the gasification feedstock as treated water in the supercritical state. The system further includes a treated water flow channel that introduces, to the countercurrent type heat exchanger, the treated water that has been discharged from the reactor, and a feedstock introduction port that introduces the feedstock to the low-temperature side flow channel.

Chugoku Electric Power Co., Hiroshima University and Toyo Koatsu Co. | Date: 2014-03-05

A double tube and the like includes: a cylindrical outer tube; a cylindrical inner tube including a helical protrusion in an outer circumferential surface, the inner tube being provided inside the outer tube; and a helical flow passage forming member that forms a helical flow passage inside the inner tube, the helical flow passage forming member being provided inside the inner tube.

Hiroshima University | Date: 2015-03-03

Disclosed is the provision of a method for assisting the detection of pancreatic cancer, the method assisting the detection of pancreatic cancer with high accuracy. In the method for assisting the detection of pancreatic cancer, the amounts of (1) miR-122-5p and (2) at least one miRNA selected from the group consisting of miR-16-5p, miR-19b-3p and miR-25-3p, all of which are contained in a test sample separated from a living body, are used as indicators. A larger amount of miR-122-5p and a smaller amount of at least one miRNA selected from the group consisting of miR-16-5p, miR-19b-3p and miR-25-3p than those in a healthy individual indicates that the living body is more likely to have developed pancreatic cancer.

Chugoku Electric Power Co., Hiroshima University and Toyo Koatsu Co. | Date: 2014-03-05

A heat exchanger includes: a flow passage unit arranged with a plurality of planar flow passage bodies each arranged with two flow passages adjacent to each other in a same plane. The plurality of the planar flow passage bodies are layered in an intersecting direction that intersects with the plane. In two of the planar flow passage bodies adjacent in the intersecting direction of the plurality of the layered planar flow passage bodies, each one of two flow passage ports in both ends of each of the flow passages of one of the planar flow passage bodies is connected to each one of two flow passage ports in both ends of each of the flow passages of another of the planar flow passage bodies. A high-pressure pipe covers an outside of the flow passage unit.

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.

Tsutani Y.,Hiroshima University | Miyata Y.,Hiroshima University | Nakayama H.,Kanagawa Cancer Center | Okumura S.,Cancer Institute Hospital | And 3 more authors.
Chest | Year: 2014

Background: The purpose of this multicenter study was to characterize ground glass opacity (GGO)-dominant clinical stage IA lung adenocarcinomas and evaluate prognosis of these tumors after sublobar resection, such as segmentectomy and wedge resection. Methods: We evaluated 610 consecutive patients with clinical stage IA lung adenocarcinoma who underwent complete resection after preoperative high-resolution CT scanning and 18 F-fluorodeoxyglucose PET/CT scanning and revealed 239 (39.2%) that had a >50% GGO component. Results: GGO-dominant tumors rarely exhibited pathologic invasiveness, including lymphatic, vascular, or pleural invasion and lymph node metastasis. There was no significant difference in 3-year recurrence-free survival (RFS) among patients who underwent lobectomy (96.4%), segmentectomy (96.1%), and wedge resection (98.7%) of GGO-dominant tumors (P = .44). Furthermore, for GGO-dominant T1b tumors, 3-year RFS was similar in patients who underwent lobectomy (93.7%), segmentectomy (92.9%), and wedge resection (100%, P = .66). Two of 84 patients (2.4%) with GGO-dominant T1b tumors had lymph node metastasis. Multivariate Cox analysis showed that tumor size, maximum standardized uptake value on 18F-fluorodeoxyglucose PET/CT scan, and surgical procedure did not affect RFS in GGO-dominant tumors. Conclusions: GGO-dominant clinical stage IA lung adenocarcinomas are a uniform group of tumors that exhibit low-grade malignancy and have an extremely favorable prognosis. Patients with GGOdominant clinical stage IA adenocarcinomas can be successfully treated with wedge resection of a T1a tumor and segmentectomy of a T1b tumor. © 2014 American College of Chest Physicians.

Yamashita H.,Hiroshima University | Yamashita H.,Seikai National Fisheries Research Institute | Koike K.,Hiroshima University
Phycological Research | Year: 2013

The dinoflagellate Symbiodinium is well known to engage symbiosis with various marine animals, including corals. Recent records of environmental Symbiodinium (occurring in the environment and separately from host animals; usually referred to as 'free-living' Symbiodinium) are of special interest, since these environmental populations are essential as symbiont sources for many host animals. In the present study, we carried out a phylogenetic analysis of environmental Symbiodinium isolates (culture strains) from sand, tide pools, or macroalgal surfaces, and environmental DNA clones extracted from the water-column, at numerous sites around Japan. Our phylogenetic analysis based on the nuclear rRNA gene (internal transcribed spacers -1, -2, and 5.8S), indicated that most of the environmental isolates form monophyletic subclades within the Clade-A lineage, and separate from a host-associated Clade-A population with high bootstrap values. Results of the partial nuclear 28S rDNA phylogeny and thecal-plate observations revealed that these environmental isolates were closely related to a previously-described 'planktonic species', Symbiodinium natans Gert Hansen et Daugbjerg, which was isolated from a plankton-net sample from the Northeast-Atlantic Ocean. On the other hand, the environmental DNA clones were also noted to be mostly nested within host-associated Symbiodinium groups scattered in various clades. These results led to the assumption that the environmental Symbiodinium can be divided into two groups. One group, as typified by environmental isolates in the present study and previous reports, may be exclusively free-living; the other group exists transiently in free-living forms, possibly having been expelled from animal hosts. The populations within the latter group probably represent environmental sources of viable symbionts, because these are normally host-associated. However, the Symbiodinium in the former group are not expected to engage in stable symbioses with host cnidarians. © 2012 Japanese Society of Phycology.

Miura I.,Hiroshima University | Ohtani H.,Hiroshima University | Ogata M.,Preservation and Research Center
Chromosome Research | Year: 2012

The frog Rana rugosa uniquely possesses two different sex-determining systems of XX/XY and ZZ/ZW, separately in the geographic populations. The sex chromosomes of both types share the same origin at chromosome 7, and the structural differences between X and Y or Z and W were evolved through two inversions. In order to ascertain the mechanisms of degeneration of W and Y chromosomes, we gynogenetically produced homozygous diploids WW and YY and examined their viability. Tadpoles from geographic group N (W NW N) containing three populations died of edema at an early developmental stage within 10 days after hatching, while tadpoles from the geographic group K (W KW K) that contained two populations died of underdeveloped growth at a much later stage, 40-50 days after fertilization. On the contrary, W NW K and W KW N hybrid embryos were viable, successfully passed the two lethal stages, and survived till the attainment of adulthood. The observed survival implies that the lethal genes of the W chromosomes are not shared by the two groups and thus demonstrates their independent degeneration histories between the local groups. In sharp contrast, a sex-linked gene of androgen receptor gene (AR) from the W chromosome was down-regulated in expression in both the groups, suggesting that inactivation of the W-AR allele preceded divergence of the two groups and appearance of the lethal genes. Besides, the YY embryos died of cardiac edema immediately after hatching. The symptom of lethality and the stage of developmental arrest differed from those for either of WW lethal embryos. We therefore conclude that the W and Y chromosomes involve no evolutionary common scenario for degeneration. © 2011 Springer Science+Business Media B.V.

Sato A.,Hiroshima University | Yamamoto H.,Hiroshima University | Sakane H.,Hiroshima University | Koyama H.,Hiroshima University | And 2 more authors.
EMBO Journal | Year: 2010

Wnt5a regulates multiple intracellular signalling cascades, but how Wnt5a determines the specificity of these pathways is not well understood. This study examined whether the internalization of Wnt receptors affects the ability of Wnt5a to regulate its signalling pathways. Wnt5a activated Rac in the b-catenin-independent pathway, and Frizzled2 (Fz2) and Ror1 or Ror2 were required for this action. Fz2 was internalized through a clathrin-mediated route in response to Wnt5a, and inhibition of clathrindependent internalization suppressed the ability of Wnt5a to activate Rac. As another action of Wnt5a, it inhibited Wnt3a-dependent lipoprotein receptor-related protein 6 (LRP6) phosphorylation and b-catenin accumulation. Wnt3a-dependent phosphorylation of LRP6 was enhanced in Wnt5a knockout embryonic fibroblasts. Fz2 was also required for the Wnt3a-dependent accumulation of b-catenin, and Wnt5a competed with Wnt3a for binding to Fz2 in vitro and in intact cells, thereby inhibiting the b-catenin pathway. This inhibitory action of Wnt5a was not affected by the impairment of clathrin-dependent internalization. These results suggest that Wnt5a regulates distinct pathways through receptor internalization dependent and -independent mechanisms. © 2010 European Molecular Biology Organization.

Han R.,Korea University | Han R.,Hiroshima University | Han R.,Korea Institute of Geoscience and Mineral Resources | Hirose T.,Japan Agency for Marine - Earth Science and Technology | Shimamoto T.,Hiroshima University
Journal of Geophysical Research: Solid Earth | Year: 2010

High-velocity friction tests were conducted on solid and hollow cylinders of Carrara (calcite) marble, dolomite marble, silicate-bearing calcite marble, and calcite gouge to investigate the strength of carbonate faults during seismic slip. The experiments, performed at normal stresses of 0.6-14.7 MPa, slip rates of 0.03-1.60 m/s, and room temperature in a rotary-shear friction testing machine, yielded an extraordinarily low steady state friction coefficient (<0.1) at slip rates of ∼1.1-1.2 m/s. The slip-weakening distance of 4-28 m became shorter at higher normal stress or frictional work rate. Strong velocity weakening was observed not only in steady state but also in nonsteady state friction, while the slip rate was changing; thus slip deceleration was accompanied by fault strength recovery. Large, rapid temperature rises in narrow shear localization zones (less than a few micrometers) induced carbonate decomposition, such as the breakdown of calcite into aggregates of CaO nanograms and CO2 in Carrara marble. Scanning electron microscope observation revealed that the shear localization zone in the highly porous decomposition product was a layer of scattered small grains (mostly <1 μm2 in diameter). These microstructures and the measured high permeability (∼10-14 m2) of the decomposed marble indicate that the dominant weakening mechanism in our experiments was possibly powder lubrication. Powder rheology at high slip rates is not yet well understood, but the frictional behavior of nanograms appears to be strongly velocity dependent. If decarbonation occurs during seismic slip in natural carbonate faults, powder lubrication may make the faults slippery even under fluid-drained conditions. Copyright 2010 by the American Geophysical Union.

Hui J.H.P.,National University of Singapore | Goyal D.,Saumya Center for Advanced Surgeries of the Knee Joint | Nakamura N.,Health Science University | Ochi M.,Hiroshima University
Arthroscopy - Journal of Arthroscopic and Related Surgery | Year: 2013

Despite financial and regulatory hurdles, Asian scientists and clinicians have made important contributions in the area of cartilage repair. Because it is impossible to include observations on all the published articles in one review, our attempt is to highlight Asian progress in this area during recent years (2005 to the present), reviewing research development and clinical studies. In the former, our discussion of in vitro studies focuses on (1) potential sources of stem cells - such as mesenchymal stem cells (MSCs) from marrow, cord blood, synovium, and mobilized peripheral blood - which are capable of enhancing cartilage repair and (2) the use of growth factors and scaffolds with and without cells. Our discussion of animal studies attempts to summarize activities in evaluating surgical procedures and determining the route of cell administration, as well as studies on matrices and scaffolds. It ranges from the use of small animals such as rats and rabbits to larger animals like pigs and dogs. The local adherent technique, enhancement of microfracture with poly(l-lactic-co-glycolic acid) scaffold, adenovirus-mediated bone morphogenic protein (BMP) genes, and MSCs - whether they are magnetically labeled, suspended in hyaluronic acid, or immobilized with transforming growth factor-β (TGF-β) - have all been able to engineer a repair of the osteochondral defect. Although published Asian reports of clinical studies on cartilage repair are few, the findings of relevant trials are summarized in our discussion of these investigations. There has been a long history of use of laboratory-derived MSCs for cartilage repair. Recent progress has suggested the potential utility of cord blood and mobilized peripheral blood in this area, as well as more injectable bone marrow (BM)-derived stem cells. Finally, we make a few suggestions on the direction of research and development activities and the need for collaborative approaches by regulatory agencies. © 2013 by the Arthroscopy Association of North America.

Han R.,Korea Institute of Geoscience and Mineral Resources | Hirose T.,Japan Agency for Marine - Earth Science and Technology | Shimamoto T.,China Earthquake Administration | Lee Y.,Korea Institute of Geoscience and Mineral Resources | Ando J.-I.,Hiroshima University
Geology | Year: 2011

Nanoparticles are known to form in narrow slip zones in natural and experimental fault zones, but their possible role in dynamic weakening of faults during seismic slip remains almost unexplored. We conducted friction experiments on periclase (MgO) nanoparticles (50 nm in average size) at rates as high as 1.3 m s-1, a typical speed of seismic slip. The nanoparticles were used as the initial gouge to avoid complexities arising from comminution and fl uid release. The dynamic friction decreased with increasing slip rate and the steady-state frictional coeffi cient reduced to as low as 0.1 at a slip rate of 1.3 m s-1. Flash heating is not effective for nanoparticles, and we propose that development of slickensides and dominant operation of nanoparticle rolling cause such a weakening. Nanoparticle lubrication appears to be as effective as melt lubrication and thermal pressurization, and the formation of nanoparticles in slip zones may be an important fault lubrication process. © 2011 Geological Society of America.

Kamiya K.,Hiroshima University | Akiba S.,Kagoshima University | Niwa O.,Fukushima Medical University | Kodama K.,Radiation Effects Research Foundation | And 4 more authors.
The Lancet | Year: 2015

Late-onset effects of exposure to ionising radiation on the human body have been identified by long-term, large-scale epidemiological studies. The cohort study of Japanese survivors of the atomic bombings of Hiroshima and Nagasaki (the Life Span Study) is thought to be the most reliable source of information about these health effects because of the size of the cohort, the exposure of a general population of both sexes and all ages, and the wide range of individually assessed doses. For this reason, the Life Span Study has become fundamental to risk assessment in the radiation protection system of the International Commission on Radiological Protection and other authorities. Radiation exposure increases the risk of cancer throughout life, so continued follow-up of survivors is essential. Overall, survivors have a clear radiation-related excess risk of cancer, and people exposed as children have a higher risk of radiation-induced cancer than those exposed at older ages. At high doses, and possibly at low doses, radiation might increase the risk of cardiovascular disease and some other non-cancer diseases. Hereditary effects in the children of atomic bomb survivors have not been detected. The dose-response relation for cancer at low doses is assumed, for purposes of radiological protection, to be linear without a threshold, but has not been shown definitively. This outstanding issue is not only a problem when dealing appropriately with potential health effects of nuclear accidents, such as at Fukushima and Chernobyl, but is of growing concern in occupational and medical exposure. Therefore, the appropriate dose-response relation for effects of low doses of radiation needs to be established. © 2015 Elsevier Ltd.

Lu W.-S.,University of Victoria | Hinamoto T.,Hiroshima University
ISCAS 2012 - 2012 IEEE International Symposium on Circuits and Systems | Year: 2012

Implementing a variable fractional delay (VFD) filter in Farrow model is costly as each coefficient of a VFD filter is a polynomial rather than a numerical scalar as in a conventional digital filter. This paper presents a method for the design of VFD filters with sparse coefficients which admits efficient implementation. The design is accomplished in two phases with the first phase identifying locations in polynomial impulse response that are suitable to be set to zero and the second phase optimizing the remaining nonzero coefficients so as for the VFD filter to best approximate a desired frequency response. Performance evaluation and comparison of the proposed algorithm relative to an equivalent nonsparse counterpart are also presented. © 2012 IEEE.

Lu W.-S.,University of Victoria | Hinamoto T.,Hiroshima University
ISCAS 2010 - 2010 IEEE International Symposium on Circuits and Systems: Nano-Bio Circuit Fabrics and Systems | Year: 2010

Is sparsity an issue in filter design problems? and why is it important? How a digital filter can be designed to have a sparse impulse response for efficient implementation while achieving improved performance relative to its non-sparse counterpart? In an attempt to address these questions, this paper comes up with a design technique for optimal linear-phase FIR filters with sparse impulse responses. ©2010 IEEE.

Arnett J.J.,Clark University | Zukauskiene R.,Mykolas Romeris University | Sugimura K.,Hiroshima University
The Lancet Psychiatry | Year: 2014

Since 1960 demographic trends towards longer time in education and late age to enter into marriage and of parenthood have led to the rise of a new life stage at ages 18-29 years, now widely known as emerging adulthood in developmental psychology. In this review we present some of the demographics of emerging adulthood in high-income countries with respect to the prevalence of tertiary education and the timing of parenthood. We examine the characteristics of emerging adulthood in several regions (with a focus on mental health implications) including distinctive features of emerging adulthood in the USA, unemployment in Europe, and a shift towards greater individualism in Japan. © 2014 Elsevier Ltd.

Horigome C.,Hiroshima University | Horigome C.,Friedrich Miescher Institute for Biomedical Research | Okada T.,Hiroshima University | Shimazu K.,Hiroshima University | And 2 more authors.
EMBO Journal | Year: 2011

Two interacting ribosome biogenesis factors, Ebp2 and Rrs1, associate with Mps3, an essential inner nuclear membrane protein. Both are found in foci along the nuclear periphery, like Mps3, as well as in the nucleolus. Temperature-sensitive ebp2 and rrs1 mutations that compromise ribosome biogenesis displace the mutant proteins from the nuclear rim and lead to a distorted nuclear shape. Mps3 is known to contribute to the S-phase anchoring of telomeres through its interaction with the silent information regulator Sir4 and yKu. Intriguingly, we find that both Ebp2 and Rrs1 interact with the C-terminal domain of Sir4, and that conditional inactivation of either ebp2 or rrs1 interferes with both the clustering and silencing of yeast telomeres, while telomere tethering to the nuclear periphery remains intact. Importantly, expression of an Ebp2ĝ€"Mps3 fusion protein in the ebp2 mutant suppresses the defect in telomere clustering, but not its defects in growth or ribosome biogenesis. Our results suggest that the ribosome biogenesis factors Ebp2 and Rrs1 cooperate with Mps3 to mediate telomere clustering, but not telomere tethering, by binding Sir4. © 2011 European Molecular Biology Organization.

News Article | January 5, 2016
Site: www.techtimes.com

By studying Cr-doped (Sb, Bi)2Te3 thin films, researchers have identified the components needed to develop electric devices that consume extremely low levels of power, reporting their findings in the journal Nature Communications. At low temperatures, the film experiences the flow of an electric current around its edges without losing energy, even without an external magnetic field. The attraction present is attributed to the ferromagnetic properties the material has, although it is not clear how it managed to gain such. For the first time, however, researchers reveal the reason why the ferromagnetic properties manifest, in hopes of creating unique materials that can be used at room temperature. Practical applications were not pursued before because for an electric current to flow without losing energy, extremely low temperature and a large external magnetic field have to be present. To address the problem, researchers believed that creating topological insulators with ferromagnetic properties will be key, and they were right. A topological insulator is neither an insulator nor a metal and features exotic properties, such as generating electric currents on its surface or edge without generating any inside. As chromium (Cr) is a magnetic element, its atom is representative of a magnet the size of an atom. North-south orientations of atom-sized magnets have the tendency to align in parallel when Cr atoms interact, and when they do, this results in the Cr-doped (Sb, Bi)2Te3 film's ferromagnetism. Still, the researchers pointed out that interatomic distances between chromium atoms are too long for interactions to be sufficient enough to produce ferromagnetism. It turns out that that atoms from the non-magnetic elements such as selenium and tellurium are the ones that mediate between magnetic interactions in chromium atoms, acting as the bond stabilizing north-south orientations so that they face just one direction. Experiments for the study were mostly conducted at SPring-8, a synchrotron radiation facility situated in Japan's Hyogo Prefecture. The facility was developed by the Japan Atomic Energy Research Institute and RIKEN, Japan's largest comprehensive research institute. "We would not have achieved perfect results without the facilities and staff there," said Akio Kimura, a Hiroshima University professor and one of the members of the research group. "I greatly appreciate their efforts." The research was supported by the Ministry of Science and Technology of China, the Natural Science Foundation of China, JSPS KAKENHI and the Helmholtz Association. Other members of the group include: Mao Ye, Xiaoming Xie, Wei Li, Shan Qiao, Siyuan Zhu, Dawei Shen, Yukiharu Takeda, Zhengtai Liu, Yuji Saitoh, Haifeng Yang, Jiajia Wang, Zhen Liu, Hong Pan, Fuhao Ji, Munisa Nurmamat and Kazuki Sumida.

News Article | December 25, 2016
Site: www.prweb.com

Researchers affiliated with the Kawasaki INnovation Gateway at SKYFRONT, have successfully generated the first ever non-human primate X-SCID models by using two genome editing techniques. The findings were published in Cell Stem Cell, July 2016. Further information about science and technology projects at Kawasaki City is available in the Kawasaki SkyFront iNewsletter that highlights research being conducted by scientists and industries affiliated with Kawasaki INnovation Gateway at SKYFRONT (KING SKYFRONT)—the City’s flagship science and technology hub launched in 2013 to focus on open innovation in the life sciences and environment. First non-human primate model for severe combined immunodeficiency: While many insights are gained into diseases and genetic disorders from rodent models, there is a pressing need to find models that can more accurately represent disease progression in the human body, such as non-human primates. The latest advances in genome editing technology are opening doors to generating non-human primate models for studying specific genetic disorders, such as X-linked severe combined immunodeficiency (X-SCID). X-SCID patients do not produce enough T-cells and natural killer cells to tackle infections. The condition stems from a defective gene, IL2-RG, and scientists are keen to know more about the disorder and how to improve treatment. Now, Erika Sasaki at the Central Institute for Experimental Animals, Kawasaki, and co-workers across Japan and the US, have successfully generated the first ever non-human primate X-SCID models by using two genome editing techniques – zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs). The team worked with marmoset monkeys because they are easy to handle and have a small body size perfect for testing small amounts of new drugs in preclinical trials. They screened the most effective ZFNs to knock-out IL2-RG gene among the 16 pairs of candidate ZFNs cultured cells. They then injected the selected ZFNs into 1 cell stage marmoset embryos and performed a specialized screening test to check for, and avoid, mosaicism (if the models carrying the mutant gene in all of the tissues in the body or not). The researchers then transferred the embryos to surrogate mothers. Of the 5 ZFN and 4 TALEN baby marmosets that were born, three have since survived to adulthood and represent the first group of X-SCID non-human primate models ever created. Further tests showed that the IL2-RG knockout marmoset models exhibited strong phenotypic similarities to human patients with X-SCID. Sasaki’s team are confident that their work paves the way for the creation of multiple gene knock-out models for specific diseases and genetic disorders. Reference and affiliations K. Sato1, R. Oiwa1, W. Kumita1, R. Henry2, T. Sakuma3, R. Ito1, R. Nozu1, T. Inoue1, I. Katano1, K. Sato4, N. Okahara1, J. Okahara1, Y. Shimizu1, M. Yamamoto1, K. Hanazawa5, T. Kawakami6, Y. Kametani7, R. Suzuki8, T. Takahashi1, E. J. Weinstein2, T. Yamamoto3, Y. Sakakibara4, S. Habu9, J. Hata1, H. Okano10*, & E. Sasaki1,11,* Generation of a nonhuman primate model of severe combined immunodeficiency using highly efficient genome editing. Cell Stem Cell 19 127-138 (2016) DOI: http://dx.doi.org/10.1016/j.stem.2016.06.003 1. Central Institute for Experimental Animals, Kawasaki, Kanagawa 210-0821, Japan 2. Horizon Discovery, Saint Louis, MO 63146, USA 3. Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Hiroshima 739-8526, Japan 4. Department of Biosciences and Informatics, Keio University, Yokohama, Kanagawa 223-8522, Japan 5. Department of Oncology, Juntendo University Nerima Hospital, Nerima-ku, Tokyo 177-8521, Japan 6. Medical Proteo Scope Company, Ltd., Yokohama, Kanagawa 236-0004, Japan 7. Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa 259-1193, Japan 8. Department of Rheumatology and Clinical Immunology, Clinical Research Center for Rheumatology and Allergy, Sagamihara National Hospital, Sagamihara, Kanagawa 252-0392, Japan 9. Atopy Research Center, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan 10. Department of Physiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan 11. Advanced Research Center, Keio University, Shinjuku-ku, Tokyo 160-8582, Japan About KING SKYFRONT KING SKYFRONT is located on the opposite side of the Tama River that separates Tokyo International Airport (also known as Haneda Airport) and the Tonomachi district of Kawasaki. The Airport plays an important role in the globalization of the innovative activities of scholars, industrialists and City administrators based at KING SKYFRONT. KING SKYFRONT was launched in 2013 as a base for scholars, industrialists and government administrators to work together to devise real life solutions to global issues in the life sciences and environment.

News Article | November 24, 2016
Site: www.eurekalert.org

A common species of Asian tree frog may actually be two separate species according to new genetic data collected by an international group of scientists. If the two groups of frogs are confirmed to be different species, assigning their scientific names may require searching historical records of foreign explorers in Japan during the 1800s. Before the frogs are officially recognized as two separate species, researchers will test if individual frogs from the two groups have unique physical or behavioral features and if they can produce healthy offspring. The project began when researchers at European universities expanded their studies on sex determination and population dynamics in amphibians to include Asian species. The species of tree frog that they chose, Hyla japonica, is found throughout Japan, the Korean peninsula, eastern China, and eastern Russia. Collaborators around the world began sending genetic samples from local frog populations to discover their evolutionary relationships. The data revealed evolutionarily distinct groups of frogs in Japan, the Korean peninsula, and eastern Russia. Ancestors of the modern frog populations likely traveled either into or out of Japan by two separate routes: from the North on a chain of islands between Russia and Japan, and from the South along a land bridge on the Philippine Sea Plate between South Korea and Japan. Japanese H. japonica populations may have been isolated into separate East and West groups. Researchers are exploring this possibility in more detail with an ongoing research project led by Ikuo Miura, PhD, an Associate Professor in Amphibian Research Center at Hiroshima University. The same separation between East and West Japan is known in other species of frogs and skinks. Miura explains that the scientific community has no definitive information about exactly what caused the divide between East and West Japan, but suggests the possibility of the expansion of ancient basin associated with volcanic activity in central Japan. Miura and Yuya Higaki, a fourth-year bachelor's degree student, are currently running genetic analysis on 50 populations of H. japonica from across Japan. They will present their preliminary results on November 26th at the annual conference of the Herpetological Society of Japan. This project is part of Miura's larger research interests in sex determination and its influence on speciation and evolution. If H. japonica is recognized as two separate species, it will be challenging for researchers to decide which species should keep the original name due to the mystery surrounding which population of H. japonica was used for the original species characterization in 1858. The German-British naturalist Albert Gunther named H. japonica after examining a specimen collected years earlier, potentially in 1826, by Philipp Siebold and Heinrich Burger, German botanists and physicians who were among the first Westerners granted official access to Japan. The modern research team visited the British Museum of Natural History to inspect the original specimen, but the location of where Siebold and Burger collected the first H. japonica is recorded only as "Japan." For now, naming the species will remain a historical mystery secondary to the ongoing scientific questions. The current research paper is published in the November 23, 2016 issue of BioMed Central Evolutionary Biology. Authors of the paper are based at the University of Lausanne (Switzerland), Leibniz-Institute of Freshwater Ecology and Inland Fisheries (Germany), Russian Academy of Sciences, Seoul National University, Ewha Woman's University (Republic of Korea), Chinese Academy of Sciences, and Hiroshima University. The species Hyla japonica is listed as Least Concern on the International Union for the Conservation of Nature (ICUN) Red List. Find more Hiroshima University news on our Facebook page: http://www. More information about the Hiroshima University Amphibian Research Center is available in both English and Japanese on their website: http://home. Information about the Herpetological Society of Japan is available in both English and Japanese on their website: http://herpetology. Academic Paper Citation: Dufresnes C, Litvinchuk SN, Borzee A, Jang Y, Li J, Miura I, Perrin N, Stock M. Phylogeography reveals an ancient cryptic radiation in East-Asian tree frogs (Hyla japonica group) and complex relationships between continental and island lineages. BioMed Central Evolutionary Biology. 23 November 2016.

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

RENO, Nev. - An earthquake much more powerful and damaging than last year's 7.8 magnitude quake could rock Kathmandu and the Himalayan Frontal Fault, an international team of seismic experts has concluded. The unsettling news comes after field research and analysis in the year following the 2015 Gorkha earthquake, which killed 9,000 people and destroyed 600,000 structures throughout the region. Geophysics professor and director of the Center for Neotectonic Studies, Steve Wesnousky of the University of Nevada, Reno, has been studying the Himalayan Frontal Fault for 20 years. He was one of the first scientists into the region to assess the geophysical impacts following last year's quake. His latest research was published in the Elsevier science journal Earth and Planetary Science Letters. "We conducted a number of paleoearthquake studies in the vicinity of Katmandu in the past year, digging trenches and studying soils and faultlines looking back over the past 2,000 years," Wesnousky said. "Coupled with the historical record, it's apparent the faults are capable of earthquakes far greater than the Gorkha earthquake." Last year's earthquake and aftershocks could be viewed as a warning of a more powerful earthquake that could rock the region with even more devastating effects. The team's observations shows the Tribeni site is probably approaching or is in the later stages of strain accumulation before a large earthquake, which could produce 15- to 30-foot high fractures in the earth. "The sum of our observations suggest that this section of the Himalayan Frontal Thrust fault, extending about 200 kilometers from Tribeni to Bagmati, may rupture simultaneously, and the next great earthquake near Kathmandu may rupture an area significantly greater than in the Gorkha earthquake," Wesnousky said. "It is prudent to consider that the fault near Kathmandu is in the later stages of a strain accumulation cycle prior to a great thrust earthquake, much greater than occurred in 2015. In these regards, the 2015 Gorkha earthquake did not diminish the current level of seismic hazard in Kathmandu." Funded by the National Science Foundation, the team visited the Kathmandu region several times for hands-on study of the faultlines. They dug two deep trenches near the mouths of major rivers at Tribeni and Bagmati. They examined structural, stratigraphic (layers of rocks and soils) and radiocarbon relationships in trenches across the fault where it has produced steep banks in soil deposited by the rivers. In these trenches is evidence that earthquake displacement along this part of the Himalayan Frontal Thrust has produced surface ruptures resulting in a scarp, a steep bank, of at least five meters or 15 feet vertical separation sometime between the years 1221 and 1262 in Tribeni, located about 200 kilometers south of Kathmandu. At the Bagmati site, the vertical separation across the scarp registers about 10 meters, or 30 feet and possibly greater, and was formed between 1031 and 1321 AD. "The scenario we developed hypothesizes that the next great earthquake may begin to the west near Tribeni and propagate into the section of fault beneath Kathmandu that did not rupture during the 2015 Gorkha earthquake," Wesnousky said. "The length of such a rupture would be about 200 kilometers or greater and capable of producing a magnitude 8 or greater earthquake. This scenario is not unique." Wesnousky's research team includes Deepak Chamlagain, a professor at Tribhuvan University in Kathmandu, Yashurhiro Kumahara a professor at Hiroshima University in Japan, Ian Pierce of the Center for Neotectonics Studies and the Nevada Seismological Laboratory at the University of Nevada, Reno, Alina Karki of Tribhuvan University and Dipendra Gautam of the Centre for Disaster and Climate Change Studies in Kathmandu. Wesnousky, a member of the Nevada Seismological Laboratory in the College of Science, has six peer-reviewed scientific papers about the Himalayan fault and more than 100 papers about earthquakes published during his career. His work centers on the foothills south of Kathmandu, just over the border in India and he has expanded his study area following the historic quake, the first large quake in that area since 1930. Following the April 2015 quake he and two of his doctoral students, Ian Pierce and Steve Angster, spent six days in the area south of Kathmandu looking for ground ruptures, following leads from villagers and residents as well as visiting various other sites studied in the past. During their studies, the graduate students sent photos and updates about their work in the Himalayas, which are posted on the University's website at http://www. . Their observations are working to further define the seismic hazard of the region as well as the mechanics of fault rupture along major continental thrust faults. A Fulbright Scholar, Wesnousky has studied earthquakes, faultlines and seismic activity throughout Nevada and parts of South America, California, Pakistan, New Zealand, Mexico, Japan, the Solomon Islands, China and India. "Steve embodies the quintessential University professor and scientist, conducting a full body of relevant research, successful teaching and community outreach," Jeff Thompson, dean of the College of Science, said. "He has done a wonderful job with the neotectonics center, informing the body of knowledge on the world's most hazardous earthquake fault zones." Photo cutline: Professor Steve Wesnousky of the College of Science at the University of Nevada, Reno examines layers of rock and soil in a trench in Tribeni, a small town in central Nepal, to study the frequency of large earthquakes on the Himalayan Frontal Fault. In a recently published study, his team concludes this 200-kilometer long section of the earthquake fault could rupture spontaneously in a magnitude 8 or greater earthquake. Photo courtesy of the University of Nevada, Reno. Nevada's land-grant university founded in 1874, the University of Nevada, Reno ranks in the top tier of best national universities by U.S. News and World Report and is steadily growing in enrollment, excellence and reputation. The University serves more than 21,000 students. Part of the Nevada System of Higher Education, the University is home to the University of Nevada, Reno School of Medicine, University of Nevada Cooperative Extension and Wolf Pack Athletics. Through a commitment to world-improving research, student success and outreach benefiting the communities and businesses of Nevada, the University has impact across the state and around the world. For more information, visit www.unr.edu.

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.

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.

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.

Fergusson C.L.,University of Wollongong | Nutman A.P.,University of Wollongong | Kamiichi T.,Hiroshima University | Hidaka H.,Hiroshima University
Gondwana Research | Year: 2013

The Early Palaeozoic Ross-Delamerian orogenic belt is considered to have formed as an active margin facing the palaeo-Pacific Ocean with some island arc collisions, as in Tasmania (Australia) and Northern Victoria Land (Antarctica), followed by terminal deformation and cessation of active convergence. On the Cambrian eastern margin of Australia adjacent to the Delamerian Fold Belt, island arc and backarc basin crust was formed and is now preserved in the Lachlan Fold Belt and is consistent with a spatial link between the Delamerian and Lachlan orogens. The Delamerian-Lachlan connection is tested with new zircon data. Metamorphic zircons from a basic eclogite sample from the Franklin Metamorphic Complex in the Tyennan region of central Tasmania have rare earth element signatures showing that eclogite metamorphism occurred at ~. 510. Ma, consistent with island arc-passive margin collision during the Delamerian(Tyennan) Orogeny. U-Pb ages of detrital zircons have been determined from two samples of Ordovician sandstones in the Lachlan Fold Belt at Melville Point (south coast of New South Wales) and the Howqua River (western Tabberabbera Zone of eastern Victoria). These rocks were chosen because they are the first major clastic influx at the base of the Ordovician 'Bengal-fan' scale turbidite pile. The samples show the same prominent peaks as previously found elsewhere (600-500. Ma Pacific-Gondwana and the 1300-1000. Ma Grenville-Gondwana signatures) reflecting supercontinent formation. We highlight the presence of ~. 500. Ma non-rounded, simple zircons indicating clastic input most likely from igneous rocks formed during the Delamerian and Ross Orogenies. We consider that the most probable source of the Ordovician turbidites was in East Antarctica adjacent to the Ross Orogen rather than reflecting long distance transport from the Transgondwanan Supermountain (i.e. East African Orogen). Together with other provenance indicators such as detrital mica ages, this is a confirmation of the Delamerian-Lachlan connection. © 2013 International Association for Gondwana Research.

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.

Gonzalez-Arroyo A.,Autonomous University of Madrid | Okawa M.,Hiroshima University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2016

We explain how to compute meson masses in the large N limit using the twisted Eguchi-Kawai model. A very simple formula is derived, and we show how it leads in a fast and efficient way to results which are in fairly good agreement with other determinations. The method is easily extensible to reduced models with dynamical fermions based on the twisted reduction idea. © 2016 The Authors.

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.

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.

Iwamoto T.,Hiroshima University | Nagai T.,Mitsubishi Group | Sawa T.,Hiroshima University
International Journal of Solids and Structures | Year: 2010

The deformation behavior and strain rate sensitivity of an epoxy resin structural adhesive and a CTBN (carboxyl-terminated butadiene-acrylonitrile)-modified epoxy resin adhesive are experimentally investigated using an INSTRON-type material testing machine and a split Hopkinson pressure bar apparatus. The experimental results show some fundamental features of a typical compressive stress-strain behavior of amorphous glassy polymers with linear elastic and nonlinear inelastic deformation stages. In the inelastic deformation, a peak stress and a strain-softening stage after the peak can be observed in the entire range of strain rate from 10- 4 to 103 s- 1. In addition, it can be found that the relationship between the peak stress and strain rate on a semi-logarithmic plot is linear in the range of low strain rate. However, the slope of the curve changes at a high strain rate, and the nonlinear behavior of the peak stress can be obtained against the strain rate. In order to describe such a nonlinear peak stress-strain rate relationship and the deformation behavior of the structural adhesives in a wide range of strain rate on the basis of the experimental results, a plastic shear strain rate is formulated. Then, a three-dimensional constitutive model is derived based on a four-elements model with an elastic series element by considering the adhesive to be a glassy polymer. The plastic deformation rate tensor is expressed by the effective stress, which is the difference between the total stress and back stress, and the plastic shear strain rate proposed here. The stress tensor can be obtained by solving nonlinear simultaneous equation. The formulated constitutive model is implemented into the commercial FE code, ABAQUS/Explicit, and then a computational simulation is performed. As a result, the validity of the proposed model is shown by comparing the experimental result. © 2009 Elsevier Ltd. All rights reserved.

Gonzalez-Arroyo A.,Autonomous University of Madrid | Okawa M.,Hiroshima University
Journal of High Energy Physics | Year: 2014

In this paper we present our results concerning the dependence of Wilson loop expectation values on the size of the lattice and the rank of the SU(N) gauge group. This allows to test the claims about volume independence in the large N limit, and the crucial dependence on boundary conditions. Our highly precise results provide strong support for the validity of the twisted reduction mechanism and the TEK model, provided the fluxes are chosen within the appropriate domain. © The Author(s).

Vohra V.,Japan Advanced Institute of Science and Technology | Vohra V.,University of Electro - Communications | Kawashima K.,RIKEN | Kawashima K.,Hiroshima University | And 6 more authors.
Nature Photonics | Year: 2015

Improving the power conversion efficiency of polymer-based bulk-heterojunction solar cells is a critical issue. Here, we show that high efficiencies of 1/410% can be obtained using the crystalline polymer PNTz4T in single-junction inverted cells with a thick active layer having a thickness of 1/4300...nm. The improved performance is probably due to the large population of polymer crystallites with a face-on orientation and the favourable' distribution of edge-on and face-on crystallites along the film thickness (revealed by in-depth studies of the blend films using grazing-incidence wide-angle X-ray diffraction), which results in a reduction in charge recombination and efficient charge transport. These results underscore the great promise of polymer solar cells and raise the hope of achieving even higher efficiencies by means of materials development and control of molecular ordering. © 2015 Macmillan Publishers Limited. All rights reserved.

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.

Lopez-Gomez J.,Complutense University of Madrid | Nagai T.,Hiroshima University | Yamada T.,Hiroshima University
Archive for Rational Mechanics and Analysis | Year: 2013

We consider the Cauchy problem for a parabolic-elliptic system in ℝ2, which is amathematical model of chemotaxis and also amodel of self-attracting particles. In the critical mass case, we determine the basin of attraction of the steady-states for the Cauchy problem through a Lyapunov functional. © 2012 Springer-Verlag.

Perez M.G.,Autonomous University of Madrid | Gonzalez-Arroyo A.,Autonomous University of Madrid | Okawa M.,Hiroshima University
Journal of High Energy Physics | Year: 2013

We study the 2+1 dimensional SU(N) Yang-Mills theory on a finite two-torus with twisted boundary conditions. Our goal is to study the interplay between the rank of the group N, the length of the torus L and the Z N magnetic flux. After presenting the classical and quantum formalism, we analyze the spectrum of the theory using perturbation theory to one-loop and using Monte Carlo techniques on the lattice. In perturbation theory, results to all orders depend on the combination x = λN L and an angle θ defined in terms of the magnetic flux (λ is 't Hooft coupling). Thus, fixing the angle, the system exhibits a form of volume independence (N L dependence). The numerical results interpolate between our perturbative calculations and the confinement regime. They are consistent with x-scaling and provide interesting information about the k-string spectrum and effective string theories. The occurrence of tachyonic instabilities is also analysed. They seem to be avoidable in the large N limit with a suitable scaling of the magnetic flux. © 2013 SISSA, Trieste, Italy.

Gonzalez-Arroyo A.,Autonomous University of Madrid | Okawa M.,Hiroshima University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2013

We present the results of a high statistics analysis of smeared Wilson loops in 4-dimensional SU(N) Yang-Mills theory for various values of N. The data is used to analyze the behavior of smeared Creutz ratios, extracting from them the value of the string tension and other asymptotic parameters. A scaling analysis allows us to extrapolate to the continuum limit for N=3, 5, 6 and 8. The results are consistent with a 1/N2 approach towards the large N limit. The same analysis is done for the TEK model (one-point lattice) for N=841 and a non-minimal symmetric twist with flux of k=9. The results match perfectly with the extrapolated large N values, confirming the validity of the reduction idea for this range of parameters. © 2012 Elsevier B.V.

Gonzalez-Arroyoa A.,Autonomous University of Madrid | Okawab M.,Hiroshima University
Journal of High Energy Physics | Year: 2010

We examine the breaking of Z N symmetry recently reported for the Twisted Eguchi-Kawai model (TEK). We analyse the origin of this behaviour and propose simple modifications of twist and lattice action that could avoid the problem. Our results show no sign of symmetry breaking and allow us to obtain values of the large N infinite volume string tension in agreement with extrapolations from results based upon straightforward methods. © SISSA 2010.

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.

Kimura S.-I.,Japan Institute for Molecular Science | Kimura S.-I.,Graduate University for Advanced Studies | Muro Y.,Hiroshima University | Takabatake T.,Hiroshima University
Journal of the Physical Society of Japan | Year: 2011

We report temperature-dependent polarized optical conductivity [ρ!ω] spectra of CeFe2Al10, which is a reference material for CeRu2Al10 and CeOs2Al10 with an anomalous magnetic transition at 28 K. The ρ!ω spectrum along the b-axis differs greatly from that in the ac-plane, indicating that this material has an anisotropic electronic structure. At low temperatures, in all axes, a shoulder structure due to the optical transition across the hybridization gap between the conduction band and the localized 4f states, namely c-f hybridization, appears at 55 meV. However, the gap opening temperature and the temperature of appearance of the quasiparticle Drude weight are strongly anisotropic indicating the anisotropic Kondo effect. The strong anisotropic nature in both electronic structure and Kondo effect is considered to be relevant to the anomalous magnetic phase transition in CeRu2Al10 and CeOs 2Al10. ©2011 The Physical Society of Japan.

Takabatake T.,Hiroshima University | Suekuni K.,Hiroshima University | Nakayama T.,Max Planck Institute for the Physics of Complex Systems | Nakayama T.,Tongji University | And 2 more authors.
Reviews of Modern Physics | Year: 2014

Type-I clathrate compounds have attracted a great deal of interest in connection with the search for efficient thermoelectric materials. These compounds constitute networked cages consisting of nanoscale tetrakaidecahedrons (14-hedrons) and dodecahedrons (12-hedrons), in which the group-1 or -2 elements in the periodic table are encaged as so-called rattling guest atoms. It is remarkable that, although these compounds have a crystalline cubic structure, they exhibit glasslike phonon thermal conductivity over the whole temperature range depending on the states of rattling guest atoms in the tetrakaidecahedron. In addition, these compounds show unusual glasslike specific heats and terahertz-frequency phonon dynamics, providing a remarkable broad peak almost identical to those observed in amorphous materials or structural glasses, the so-called boson peak. An efficient thermoelectric effect is realized in compounds showing these glasslike characteristics. In this decade, a number of experimental works dealing with type-I clathrate compounds have been published. These are diffraction, thermal, and spectroscopic experiments in addition to those based on heat and electronic transport. These form the raw materials for this review based on advances from this decade. The subject of this review involves interesting phenomena from the viewpoint not only of physics but also of the practical problem of elaborating efficient thermoelectric materials. This review presents a survey of a wide range of experimental investigations of type-I clathrate compounds, together with a review of theoretical interpretations of the peculiar thermal and dynamic properties observed in these materials. © 2014 American Physical Society.

Hiroshima University and Q - Cells SE | Date: 2011-08-03

Provided is a differentiation-inducing culture medium additive for inducing bone differentiation of at least one type of cell selected from the group consisting of a stem cell, a dental pulp cell, a periodontal ligament cell, a placenta, an amnion, and a fibroblast under a serum-free condition, and a use of the differentiation-inducing culture medium additive. The differentiation-inducing culture medium additive of the present invention for inducing differentiation of a stem cell under a serum-free condition at least contains at least one growth factor selected from the group consisting of EGF, FGF, and PDGF; dexamethasone; and -glycerophosphate. The differentiation-inducing culture medium additive of the present invention does not require ascorbic acid 2-phosphate and ITS, which are normally essential for bone differentiation. Further, bone differentiation can be promoted by adding phospholipid.

Mitsui Engineering, Shipbuilding Co., Hiroshima University and Gifu University | Date: 2014-04-09

The present invention provides: uracil-requiring Moorella bacteria obtained by destroying a gene coding for orotidine-5-phosphate decarboxylase; and transforming-gene-introduced Moorella bacteria obtained by introducing a gene coding for orotidine-5-phosphate decarboxylase and a transforming-gene to a chromosome of the uracil-requiring Moorella bacteria. The present invention was accomplished by uracil-requiring Moorella bacteria, comprising an MTA-D-pF strain that is obtained by destroying a gene coding for orotidine-5-phosphate decarboxylase on a chromosome of Moorella bacteria.

Mitsui Engineering, Shipbuilding Co., Gifu University and Hiroshima University | Date: 2012-06-01

The present invention provides a primer set used for transformation that imparts a uracil requiring property by deleting or destroying a gene coding for orotidine-5-phosphate decarboxylase in Moorella bacteria. The present invention is accomplished by a primer set that is used for creating a uracil requiring strain obtained by deleting or destroying a gene coding for orotidine-5-phosphate decarboxylase in Moorella bacteria by homologous recombination and is represented by SEQ ID No. 1 and 2 that amplify an upstream region adjacent to said gene coding for orotidine-5-phosphate decarboxylase.

Mitsui Engineering, Shipbuilding Co., Gifu University and Hiroshima University | Date: 2012-06-01

The present invention provides uracil-requiring Moorella bacteria obtained by destroying a gene coding for orotidine-5-phosphate decarboxylase; and transforming-gene-introduced Moorella bacteria obtained by introducing a gene coding for orotidine-5-phosphate decarboxylase and a transforming-gene to a chromosome of the uracil-requiring Moorella bacteria. The present invention was accomplished by uracil-requiring Moorella bacteria, comprising an MTA-D-pF strain that is obtained by destroying a gene coding for orotidine-5-phosphate decarboxylase on a chromosome of Moorella bacteria.

Mitsui Engineering, Shipbuilding Co., Hiroshima University and Gifu University | Date: 2014-04-09

The present invention provides a primer set used for transformation that imparts a uracil requiring property by deleting or destroying a gene coding for orotidine-5-phosphate decarboxylase in Moorella bacteria. The present invention is accomplished by a primer set that is used for creating a uracil requiring strain obtained by deleting or destroying a gene coding for orotidine-5-phosphate decarboxylase in Moorella bacteria by homologous recombination and is represented by SEQ ID No. 1 and 2 that amplify an upstream region adjacent to said gene coding for orotidine-5-phosphate decarboxylase.

Hiroshima University and Hiroshima Industrial Promotion Organization | Date: 2010-01-13

A chicken embryonic stem cell is established, which stably has pluripotency and an ability of being differentiated into a germ cell. For evaluating on whether or not the chicken embryonic stem cell can be applied to genetic modification technique, detection is made on a protein which serves as an indicator of the ability of being differentiated into a germ cell.This provides (i) a chicken embryonic stem cell applicable to genetic modification technique and (ii) a method for evaluation of the chicken embryonic stem cell.

Hiroshima University and Nippon Oil Corporation | Date: 2013-09-03

A photoelectric conversion element has a structure where a hole transport layer, a photoelectric conversion layer, and an electron transport layer are held between a first electrode and a second electrode. The photoelectric conversion layer is a bulk heterojunction layer, and fullerene or a fullerene derivative is used as an n-type organic semiconductor. As a p-type organic semiconductor, a polymer represented by the following Expression is used. In the Expression, R_(1), R_(2), R_(3), and R_(4 )each independently represent any one of a branched alkyl group, a linear alkyl group, an alkyl ester group, a carboxy alkyl group, and an alkoxy group. Independently, X is any one of S, O, and N.

Hiroshima University and Q - Cells SE | Date: 2015-10-16

Provided is a differentiation-inducing culture medium additive for inducing bone differentiation of at least one type of cell selected from the group consisting of a stem cell, a dental pulp cell, a periodontal ligament cell, a placenta, an amnion, and a fibroblast under a serum-free condition, and a use of the differentiation-inducing culture medium additive. The differentiation-inducing culture medium additive of the present invention for inducing differentiation of a stem cell under a serum-free condition at least contains at least one growth factor selected from the group consisting of EGF, FGF, and PDGF; dexamethasone; and -glycerophosphate. The differentiation-inducing culture medium additive of the present invention does not require ascorbic acid 2-phosphate and ITS, which are normally essential for bone differentiation. Further, bone differentiation can be promoted by adding phospholipid.

Nippon Oil Corporation and Hiroshima University | Date: 2014-01-08

A photoelectric conversion element 10 has a structure where a hole transport layer 40, a photoelectric conversion layer 50, and an electron transport layer 60 are held between a first electrode 30 and a second electrode 70. The photoelectric conversion layer 50 is a bulk heterojunction layer, and fullerene or a fullerene derivative is used as an n-type organic semiconductor. As a p-type organic semiconductor, a polymer represented by the following Expression (1) is used. In Expression (1) , R_(1), R_(2), R_(3), and R_(4) each independently represent any one of a branched alkyl group, a linear alkyl group, an alkyl ester group, a carboxy alkyl group, and an alkoxy group. Independently, X is any one of S, O, and N.

News Article | December 29, 2015
Site: www.nanotech-now.com

Home > Press > A clue to generate electric current without energy consumption at room temperature Abstract: A group of researchers in Japan and China identified the requirements for the development of new types of extremely low power consumption electric devices by studying Cr-doped (Sb, Bi)2Te3 thin films. This study has been reported in Nature Communications. At extremely low temperatures, an electric current flows around the edge of the film without energy loss, and under no external magnetic field. This attractive phenomenon is due to the material's ferromagnetic properties; however, so far, it has been unclear how the material gains this property. For the first time, researchers have revealed the mechanism by which this occurs. "Hopefully, this achievement will lead to the creation of novel materials that operate at room temperature in the future," said Akio Kimura, a professor at Hiroshima University and a member of the research group. Their achievement can be traced back to the discovery of the quantum Hall effect in the 1980's, where an electric current flows along an edge (or interface) without energy loss. However, this requires both a large external magnetic field and an extremely low temperature. This is why practical applications have not been possible. Researchers believed that this problem could be overcome with new materials called topological insulators that have ferromagnetic properties such as those found in Cr-doped (Sb, Bi)2Te3. A topological insulator, predicted in 2005 and first observed in 2007, is neither a metal nor an insulator, and has exotic properties. For example, an electric current is generated only at the surface or the edge of the material, while no electric current is generated inside it. It looks as if only the surface or the edge of the material has metallic properties, while on the inside it is an insulator. At extremely low temperatures, a thin film made of Cr-doped (Sb, Bi)2Te3 shows a peculiar phenomenon. As the film itself is ferromagnetic, an electric current is spontaneously generated without an external magnetic field and electric current flows only around the edge of the film without energy loss. However, it was previously unknown as to why Cr-doped (Sb, Bi)2Te3 had such ferromagnetic properties that allowed it to generate electric current. "That's why we selected the material as the object of our study," said Professor Kimura. Because Cr is a magnetic element, a Cr atom is equivalent to an atomic-sized magnet. The N-S orientations of such atomic-sized magnets tend to be aligned in parallel by the interactions between the Cr atoms. When the N-S orientations of Cr atoms in Cr-doped (Sb, Bi)2Te3 are aligned in parallel, the material exhibits ferromagnetism. However, the interatomic distances between the Cr atoms in the material are, in fact, too long to interact sufficiently to make the material ferromagnetic. The group found that the non-magnetic element atoms, such as the Sb and Te atoms, mediate the magnetic interactions between Cr atoms and serve as the glue to fix the N-S orientations of Cr atoms that face one direction. In addition, the group expects that its finding will provide a way to increase the critical temperature for relevant device applications. The experiments for this research were mainly conducted at SPring-8. "We would not have achieved perfect results without the facilities and the staff there. They devoted themselves to detecting the extremely subtle magnetism that the atoms of non-magnetic elements exhibit with extremely high precision. I greatly appreciate their efforts," Kimura said. Authors and their affiliations: Mao Ye1,2, Wei Li1,2, Siyuan Zhu3, Yukiharu Takeda4, Yuji Saitoh4, Jiajia Wang5, Hong Pan6, Munisa Nurmamat3, Kazuki Sumida3, Fuhao Ji6, Zhen Liu6, Haifeng Yang1, Zhengtai Liu1, Dawei Shen1,2, Akio Kimura3, Shan Qiao1,2,5, and Xiaoming Xie1,2,5 1 State Key Laboratoryof Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences 2 CAS-Shanghai Science Research Center 3 Graduate School of Science, Hiroshima University 4 Condensed Matter Science Division, Quantum Beam Science Center, Japan Atomic Energy Agency 5 School of physical science and technology, ShanghaiTech University 6 Department of Physics, State Key Laboratory of Surface Physics, and Laboratory of Advanced Materials, Fudan University For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

News Article | October 26, 2016
Site: www.eurekalert.org

Mathematical analysis has led researchers in Japan to a formula that can describe the movement of DNA inside living human cells. Using these calculations, researchers may be able to reveal the 3D architecture of the human genome. In the future, these results may allow scientists to understand in detail how DNA is organized and accessed by essential cellular machinery. Previous techniques of studying the genome's architecture have relied on methods that require killing the cells. This research project, involving collaborators at multiple institutes in Japan, used alternative molecular and cell biology techniques to keep the cells alive and collect data about the natural movement of DNA. DNA is often envisaged as a stable and static code, but the genome as a whole is actually an active molecule that moves around and changes shape. Currently, scientists can sequence the entire basic code of DNA, but knowing the larger-scale 3D architecture of the genome would reveal more information about how cells use the code. While the cell is growing, DNA is stored as an unraveled spool of string; certain portions (euchromatin) are more loosely wound, and therefore accessible to the cellular machinery that turns DNA into protein, than other areas that are kept tightly wound (heterochromatin). When the cell prepares to split in half during cell division, it packages all of the chromatin into tightly-wound, X-shaped chromosomes. "Our calculations consider the fractal dimensions of the DNA, which shows how densely the DNA is packed inside the cell. The way the DNA is packed may indicate how the cell uses certain genes," said Soya Shinkai, PhD, Assistant Professor at Hiroshima University and first author of the research paper. Along the "string" of chromatin are regularly-spaced, barrel-shaped "beads" of DNA-protein complexes called nucleosomes. Researchers tracked nucleosomes' movement around the cell to understand where and how chromatin is stored. Researchers labeled the nucleosomes with fluorescent tags and took microscopy images during the growth phase of human cells. They then used theories of polymer physics to quantify the movement of the nucleosomes. "Every second, a 10 nanometer-sized nucleosome can move 100 nanometers. The constant, subtle random forces within the cell make the chromatin move around so much," said Shinkai. Before a cell can use a gene, the DNA must be completely unwound. Areas of chromatin containing frequently used genes are less tightly wrapped than areas of chromatin with infrequently used genes. A model to visualize how chromatin is packed within the cell could allow researchers to understand which genes are accessed most or least often and how the genome is physically organized. "Our calculations are relevant to local chromatin structures, but this method could also be extended to whole chromosomes. These mathematical formulas are a theory for how to interpret the visual data from microscope images of DNA moving within the cell," said Yuichi Togashi, PhD, Associate Professor at Hiroshima University and last author of the research paper. Future research projects will include finding new microscopy and DNA labeling techniques to visually track the movement of individual nucleosomes over longer periods time. The four researchers who published the recent paper are experts in theoretical and computational biophysics, structural biology, cell biology, and molecular biology. The results come from a research project made possible by an interdisciplinary team of scientists associated with the Research Center for the Mathematics on Chromatin Live Dynamics at Hiroshima University. Other collaborators for the project include the National Institute of Genetics (Japan), Keio University, and Sokendai Graduate University for Advanced Studies. Find more Hiroshima University news on our Facebook page: http://www. Information about the RcMcD is available in both English and Japanese at: http://www.

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

Galaxies in the universe trace patterns on very large scales; there are large empty regions (called "voids") and dense regions where the galaxies exist. This distribution is called the cosmic web. The most massive concentrations of galaxies are clusters. The formation of the cosmic web is governed by the action of gravity on the invisible mysterious "dark matter" that exists throughout the universe. The normal baryonic material one can see falls into the dark matter halos and forms galaxies. The action of gravity over about 14-billion-year history of the universe makes the halos cluster together. The location of galaxies or clusters in this enormous cosmic web tests our understanding of the way structure forms in the universe. Increasingly, deeper and more extensive observations with telescopes like Subaru Telescope provide a clearer picture of the way galaxies evolve within the cosmic web. Of course, one cannot see the dark matter directly. However, one can use the galaxies that are seen to trace the dark matter. It is also possible to use the way the gravity of clusters of galaxies distort more distant background galaxies, weak gravitational lensing, as another tracer. The Hiroshima group combined these two tracers: galaxies and their weak lensing signal to map the changing role of massive star-forming galaxies as the universe evolves. Weak lensing is a phenomenon that provides a powerful technique for mapping the changing contribution of star-forming galaxies as tracers of the cosmic web. The cluster of galaxies and surrounding dark matter halo act as a gravitational lens. The lens bends the light passing through from more distant galaxies and distorts the images of them. The distortions of the appearance of the background galaxies provide a two-dimensional image of the foreground dark matter distribution that acts as a huge lens. The excellent imaging of the Subaru Telescope covering large regions of the sky provides exactly the data needed to construct maps of this weak lensing. Dr. Yousuke Utsumi, a member of Hyper Suprime-Cam building team and a project assistant professor at Hiroshima University, conducted a 1-hour observation of a 4-deg2 patch of sky in the direction of the constellation Cancer. Figure 1 shows a close-up view of a cluster of galaxies with the weak lensing map tracing the matter distribution. The highest peaks in the maps correspond the foreground massive clusters of galaxies that lie 5 billion light-years away. To map the three-dimensional distribution of the foreground galaxies, spectrographs on large telescopes like the 6.5-meter MMT disperse the light with a grating. The expansion of the universe shifts the light to the red and by measuring this shift one measures the distances to the galaxies. Using spectroscopy places the galaxies in the cosmic web. The observations locate star-forming galaxies and those that are no longer forming stars. Collaborators led by Dr. Margaret Geller (Harvard-Smithsonian Center for Astrophysics) conducted spectroscopic measurements for galaxies. The Hectospec instrument on the MMT enables measurements of redshifts for 250 galaxies at a time. The survey contains measurements for 12,000 galaxies. The MMT redshift survey provides the map for the way all types of galaxies might contribute to the weak lensing map. Because the MMT survey provides distances to the galaxies, slices of the map at different distances corresponding to different epochs in the history of the universe can also be made and compared with the lensing map. The MMT survey provides a predicted map of the cosmic web based on the positions of galaxies in three-dimensional space. Research team compared this map with the weak lensing map to discover the similarities. Figure 2 shows that both the highest peak and the largest empty regions are similar in the two maps. In other words, the matter distribution traced by the foreground galaxies and the distribution traced by the Subaru weak lensing map are similar. There are two complementary views of the cosmic web in this patch of the universe. If they slice up the three-dimensional map in different redshift or time slices, they can examine the way the correspondence between these maps and the weak lensing map changes for different slices (Figure 3). Remarkably, the distribution of star-forming galaxies around a cluster of galaxies in the more distant universe (5 billion years ago) corresponds much more closely with the weak lensing map than a slice of the more nearby universe (3 billion years ago). In other words, the contribution of star-forming galaxies to the cosmic web is more prominent in the distant universe. These maps are the first demonstration of this effect in the weak lensing signal. The research team provides a new window on galaxy evolution by comparing the three-dimensional galaxy distribution mapped with a redshift survey including star-forming galaxies to a weak lensing map based on Subaru imaging. "It turns out that the contribution of star-forming galaxies as tracers of the mass distribution in the distant universe is not negligible," said Dr. Utsumi. "The HSC weak lensing map should contain signals from more distant galaxies in the 8 billion-year-old universe. Deeper redshift surveys combined with similar weak lensing maps should reveal an even greater contribution of star-forming galaxies as tracers of the matter distribution in this higher redshift range. Using the next generation spectrograph for the Subaru Telescope, Prime Focus Spectrograph (PFS), we hope to extend our maps to the interesting era." Please follow SpaceRef on Twitter and Like us on Facebook.

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

Hiroshima University scientists have identified a new species of parasite infecting an invasive freshwater fish on the subtropical island of Okinawa, Japan. The results are part of a project to find parasites that have arrived in Japan with their non-native hosts and understand the role of parasites in natural ecosystems. Tracking parasites can be one scientific method to monitor ecosystem health and attempt to conserve biodiversity. The project began in 2012 when one of the researchers was trying to fill some of his free time. Masato Nitta, now a second-year PhD student at Hiroshima University, recognized some invasive fish in the stream that runs through the campus of the University of the Ryukyus in Okinawa, Japan, the university that hosted his research team during their field studies. "It was just for play, not for official study. I saw two of the invasive catfish and I decided to try to catch them and check what parasites they had because I was curious. When I put the parasites under the microscope, they looked a little bit strange. No one had seen these parasites in Japan before," said Nitta. Nitta and his supervisor, Kazuya Nagasawa, PhD, from the Graduate School of Biosphere Science at Hiroshima University, returned to Okinawa in 2015 to study the parasites of the invasive vermiculated sailfin catfish in more detail. Their latest research paper announces a species new to science, two species found in Japan for the first time, and confirms the presence of the species they identified in 2012. The four species described in the research paper infect the gills of the catfish and are in the class Monogenea. Only one species of monogenean is known to infect mammals, specifically the eyes of hippopotamus, so there is no record and little reason to suspect that the parasites pose any danger to humans directly. These foreign parasite species are most likely not a threat to Japan's native freshwater fish because monogeneans are known to be very specific to their host species and spend their entire lifecycle in a single host. The catfish species that hosts the parasites is native to the Amazon River and likely arrived in Japan in the 1980s by way of southeast Asian countries as part of the pet trade. The fish is sometimes eaten for food in Brazil, but is considered an ornamental fish in Japan. Even in its native habitat, the catfish's normal parasitic infections are not well studied. "I want to go to Brazil to do the work! But when I speak with local scientists, they tell me that no one can go so far into the jungle to find these fish in their natural habitat. But still, it is one of my dreams," said Nitta. The invasive species of freshwater catfish is Pterygoplichthys disjunctivus (Siluriformes: Loricariidae). The four species of monogenean parasite described in the research paper are: Unilatus brittani, Unilatus unilatus, Heteropriapulus heterotylus (first identified in Japan in 2012), and Trinigyrus peregrinus (new species identified in 2015). The results are published in the November 2016 issue of the journal Species Diversity, published by the Japanese Society of Systematic Zoology. Find more Hiroshima University news on our Facebook page: http://www. More information about the Laboratory of Aquaculture at Hiroshima University is available on their website: http://home.

2nd Annual Genome Editing & Engineering Conference to be held on 6th - 7th February 2017 in San Diego, CA will see participation from global experts from pharmaceutical, bio-pharmaceutical companies, universities and academic institutions. -- MarketsandMarkets, organizers of the 2Annual Genome Editing & Engineering Conference, are thrilled to announce that Dr. Dana Carroll, Distinguished Professor, Department of Biochemistry, University of Utah School of Medicine has joined the prestigious speaker panel at the conference taking place in San Diego.Dr. Carroll, a pioneer in the development and applications of genome editing with programmable nucleases, will be delivering the keynote on 'Issues in Programmable Genome Editing' helping provide key insights on how gene editing has powerful applications in various areas including agriculture and medicine.The conference will gather key industry leaders and researchers from research institutes, academic institutions, pharma and bio – pharma organizations to address the concepts, challenges and applications of genome editing tools like CRISPR/Cas9, TALENs. Key discussions at the event will include RNA guided nuclease for genome modifications, different gene delivery systems, CRISPR as a molecular tool for programmable gene expression and gene therapy, human gene therapy using Zebrafish model, gene knock in and genomic screening using TALEN and CRISPR, CRISPR biomedical research applications, RNAi based screening technologies, genome editing for disease modeling and NgAgo as the latest tool for genome editing.The marketing team at MarketsandMarkets did a small pre – event interview with Dr. Carroll, talking about the emerging research areas in genome editing and engineering for the treatment of disorders. Dr. Carroll mentioned a few areas where gene editing has been instrumental in finding results namely 'Improvement of the efficiency of homologous repair to allow easy gene correction', 'Delivery methods for in vivo treatments' and 'Development of "universal" donor cells to allow more affordable treatments'. He further added, "Genome editing depends on cellular DNA repair activities, so research on aspects of genome editing will help us learn more about those activities."Joining him on the speaker panel will be genomics experts representing organizations such as University of Utah School of Medicine, Massachusetts Institute of Technology, J. Craig Venter Institute, University of Nebraska Medical Center, University of California, University of Washington, University of Southern California, University of Rochester, National Institutes of Health, University of Texas, University of Minnesota, Hiroshima University and Wellcome Trust Sanger Institute. bThe conference will be an excellent opportunity to network, share expertise with industry peers and stay updated about the latest advancements in genomics and gene engineering. The conference is supported by California Life Sciences Association (CLSA), ArizonaBio, BioUtah, Colorado BioScience Association, Georgia Bio, Northwest Association for Biomedical Research (NWABR) and The Bioscience Association of Maine (BAM). The event is co - located with the 2Annual Biomarker Conference and 2Annual NGS Data Analysis and Informatics Conference and is scheduled for 6th – 7th February 2017.

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.

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.

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.

Kashima S.,Hiroshima University | Yorifuji T.,Okayama University of Science | Tsuda T.,Okayama University of Science | Eboshida A.,Hiroshima University
Occupational and Environmental Medicine | Year: 2012

Objective: Desert dust, which is included in course particles, is considered to have potential toxicity. The effect modification of desert dust on associations between anthropogenic air pollution and mortality has been evaluated. However, the independent effects of Asian dust are less clear. Thus, we evaluated the effects of Asian dust on mortality independent of particulate matter (PM) in western Japan. Methods: We obtained daily mean concentrations of Asian dust using Light Detection and Ranging measurements and suspended particulate matter (SPM) concentrations (approximately PM8) during March 2005 to December 2010. We then evaluated city-specific associations of Asian dust and SPM with daily mortality using a time-series analysis targeting 1 379 052 people aged 65 or above living in 47 cities. The city-specific results were then combined with a Bayesian-hierarchical model. Results: Asian dust did not modify the effects of SPM on mortality. Meanwhile, Asian dust was adversely associated with mortality independent of SPM. The excess risk following a 10 μ/m3 increase in mean of the current to the previous 2 days Asian dust concentration was 0.6% (95% CI 0.1 to 1.1) for heart disease, 0.8% (95% CI 0.1 to 1.6) for ischaemic heart disease, 2.1% (95% CI 0.3 to 3.9) for arrhythmia and 0.5% (95% CI 0.2 to 0.8) for pneumonia mortality. Furthermore, the effects of Asian dust were stronger in northern areas close to the Eurasian continent (source of Asian dust). Conclusions: Asian dust had adverse effects on circulatory and respiratory mortality independent of PM.

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.

Ikeda T.,Hiroshima University | Ibrahim R.A.,Wayne State University | Harata Y.,Hiroshima University | Kuriyama T.,Terumo Corporation
Journal of Fluid Mechanics | Year: 2012

Nonlinear responses of surface waves in rigid square and nearly square tanks partially filled with liquid subjected to obliquely horizontal, sinusoidal excitation are investigated theoretically and experimentally. Two predominant modes of sloshing are significantly coupled nonlinearly because their natural frequencies are nearly identical resulting in 1:1 internal resonance. Therefore, if only one of these modes is directly excited, the other mode is indirectly excited due to the nonlinear coupling. In the nonlinear theoretical analysis, the modal equations of motion are derived for the two predominant sloshing modes as well as five higher sloshing modes. The linear viscous terms are incorporated in order to consider the damping effect of sloshing. The expressions for the frequency response curves are determined using van der Pols method. The influences of the excitation direction and the aspect ratio of the tank cross-section on the frequency response curves are numerically examined. Planar and swirl motions of sloshing, and Hopf bifurcations followed by amplitude modulated motions including chaotic motions, are predicted when the excitation frequency is close to one of the natural frequencies of the two predominant sloshing modes. Lyapunov exponents are calculated and reveal the excitation frequency range over which liquid chaotic motions occur. In addition, bifurcation sets are shown to clarify the influences of the parameters on the change in the structural stability. The theoretically predicted results are in good agreement with the measured data, thus the theoretical analysis was experimentally validated. © 2012 Cambridge University Press.

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.

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.

Chayama K.,Hiroshima University | Takahashi S.,Hiroshima University | Toyota J.,Sapporo Kosei General Hospital | Karino Y.,Sapporo Kosei General Hospital | And 6 more authors.
Hepatology | Year: 2012

Patients with chronic hepatitis C virus (HCV) infection and previous null response to pegylated interferon (Peg-IFN) and ribavirin (RBV) have limited therapeutic options. HCV genotype 1 is the most common worldwide and the most difficult to treat; genotype 1b is the most common subtype of genotype 1 outside North America. The enhanced antiviral activity achieved by combining two direct-acting antiviral (DAA) agents may improve clinical outcomes. This open-label, phase IIa study included 10 patients with chronic HCV genotype 1b infection and previous null response (<2 log 10 reduction in HCV RNA after 12 weeks) to Peg-IFN and RBV. Patients received dual DAA treatment for 24 weeks with the nonstructural protein 5A replication complex inhibitor, daclatasvir (60 mg once-daily), and the nonstructural protein 3 protease inhibitor, asunaprevir (initially 600 mg twice-daily, then subsequently reduced to 200 mg twice-daily). The primary efficacy endpoint was the proportion of patients with sustained virologic response (SVR) at 12 weeks post-treatment (SVR 12). Nine patients completed 24 weeks of treatment; 1 patient discontinued treatment after 2 weeks. In the 9 patients who completed the full course of treatment, HCV RNA was undetectable at week 8 and remained undetectable through the end of treatment; all 9 patients achieved SVR 12 and SVR 24. HCV RNA also remained undetectable post-treatment in the patient who discontinued after 2 weeks. There was no viral breakthrough. Diarrhea and headache, generally mild, were the most common adverse events; transaminase elevations were reported in 3 patients, but did not result in discontinuation. Conclusions: Dual therapy with daclatasvir and asunaprevir, without Peg-IFN and RBV, can achieve high SVR rates in difficult-to-treat patients with HCV genotype 1b infection and previous null response to Peg-IFN and RBV. (HEPATOLOGY 2011) © 2011 American Association for the Study of Liver Diseases.

Mochizuki H.,University of California | Mochizuki H.,Hiroshima University | Lesley A.G.,University of California | Brandt J.D.,University of California
Ophthalmology | Year: 2011

Purpose: The mechanism of cupping reversal seen after lowering intraocular pressure (IOP) in pediatric glaucoma is unknown. Theories include forward movement of the lamina cribrosa or shrinkage of a stretched scleral canal. Our study aimed to quantify changes in optic disc size occurring in children who had undergone glaucoma surgery. Design: Retrospective, single-center, observational case series. Participants: Children undergoing incisional surgery for pediatric glaucoma at the University of California, Davis. Methods: The electronic charts of all patients with pediatric glaucoma were reviewed for the presence of RetCam digital optic nerve photographs (Clarity Medical Systems, Pleasanton, CA). Cases in which the photographs (baseline and follow-up after surgical intervention) were of sufficient quality were analyzed. The optic disc margin was outlined manually using ImageJ software. Inter-session changes in magnification were accounted for by drawing a control polygon joining 4 or 5 fixed landmarks (e.g., vessel crossings) to include a second larger area containing the optic nerve. The optic disc area (in pixels adjusted with the control polygon) was compared between baseline and follow-up images. Main Outcome Measures: Change in disc area between baseline and follow-up after surgery. Results: We identified 29 eyes for which baseline and follow-up images were available for analysis. Fifteen eyes of 9 children showed clinically obvious cupping reversal. Fourteen eyes of 12 children showed no cupping reversal. Disc area decreased by 6.8% (95% confidence interval [CI], -10.0 to -3.3) in the obvious reversal group and increased by 4.3% (95% CI, +1.0 to +7.6) in the no reversal group after surgery (P < 0.0001; Student t test). Percent change in disc area is correlated to percent change in IOP (r=0.540; P=0.0025) and axial length (r=0.534; P=0.0028). Conclusions: When cupping reversal is clinically apparent after successful IOP-lowering surgery for congenital glaucoma, the scleral canal shrinks in area. In contrast, when cupping reversal is not observed, the scleral ring continues to enlarge, indicating ongoing stress on the optic nerve. Clinically obvious cupping reversal is less frequently observed in adults after surgery, which may reflect a lower elasticity of the scleral ring in adults compared with children. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article. © 2011 American Academy of Ophthalmology.

Kobayashi K.,Sophia University | Ohtsuki T.,Sophia University | Imura K.-I.,Hiroshima University | Imura K.-I.,Max Planck Institute For Physik Komplexer Systeme | And 2 more authors.
Physical Review Letters | Year: 2014

The quantum phase transition between the three dimensional Dirac semimetal and the diffusive metal can be induced by increasing disorder. Taking the system of a disordered Z2 topological insulator as an important example, we compute the single particle density of states by the kernel polynomial method. We focus on three regions: the Dirac semimetal at the phase boundary between two topologically distinct phases, the tricritical point of the two topological insulator phases and the diffusive metal, and the diffusive metal lying at strong disorder. The density of states obeys a novel single parameter scaling, collapsing onto two branches of a universal scaling function, which correspond to the Dirac semimetal and the diffusive metal. The diverging length scale critical exponent ν and the dynamical critical exponent z are estimated, and found to differ significantly from those for the conventional Anderson transition. Critical behavior of experimentally observable quantities near and at the tricritical point is also discussed. © 2014 American Physical Society.

Hayashi N.,Kansai Rosai Hospital | Okanoue T.,Saiseikai Suita Hospital | Tsubouchi H.,Kagoshima University | Toyota J.,Sapporo Kosei General Hospital | And 2 more authors.
Journal of Viral Hepatitis | Year: 2012

The aims of this phase III study were to assess the efficacy and safety of telaprevir in combination with peginterferon alfa-2b (PEG-IFN) and ribavirin (RBV) for difficult-to-treat patients who had not achieved sustained virological response (SVR) to prior regimens in Japan. The subjects were 109 relapsers (median age of 57.0 years) and 32 nonresponders (median age of 57.5 years) with hepatitis C virus genotype 1. Patients received telaprevir (750 mg every 8 h) for 12 weeks and PEG-IFN/RBV for 24 weeks. The SVR rates for relapsers and nonresponders were 88.1% (96/109) and 34.4% (11/32), respectively. Specified dose modifications of RBV that differed from that for the standard of care were introduced to alleviate anaemia. RBV dose reductions were used for 139 of the 141 patients. The SVR rates for relapsers did not depend on RBV dose reduction for 20-100% of the planned dose (SVR rates 87.5-100%, P < 0.05). Skin disorders were observed in 82.3% (116/141). Most of the skin disorders were controllable by anti-histamine and/or steroid ointments. The ratios of discontinuation of telaprevir only or of all the study drugs because of adverse events were 21.3% (30/141) and 16.3% (23/141), respectively. A frequent adverse event leading to discontinuation was anaemia. Telaprevir in combination with PEG-IFN/RBV led to a high SVR rate for relapsers and may offer a potential new therapy for nonresponders even with a shorter treatment period. © 2011 Blackwell Publishing Ltd.

Satoh N.,Okinawa Institute of Science and Technology | Tagawa K.,Hiroshima University | Takahashi H.,Japan National Institute for Basic Biology
Evolution and Development | Year: 2012

More than 550 million years ago, chordates originated from a common ancestor shared with nonchordate deuterostomes by developing a novel type of larva, the "tadpole larva." The notochord is the supporting organ of the larval tail and the most prominent feature of chordates; indeed, phylum Chordata is named after this organ. In this review, we discuss the molecular mechanisms involved in the formation of the notochord over the course of chordate evolution with a special emphasis on a member of T-box gene family, Brachyury. Comparison of the decoded genome of a unicellular choanoflagellate with the genomes of sponge and cnidarians suggests that T-box gene family arose at the time of the evolution of multicellular animals. Gastrulation is a morphogenetic movement that is essential for the formation of two- or three-germ-layered embryos. Brachyury is transiently expressed in the blastopore (bp) region, where it confers on cells the ability to undergo invagination. This process is involved in the formation of the archenteron in all metazoans. This is a "primary" function of Brachyury. During the evolution of chordates, Brachyury gained an additional expression domain at the dorsal midline region of the bp. In this new expression domain, Brachyury served its "secondary" function, recruiting another set of target genes to form a dorsal axial organ, notochord. The Wnt/β-catenin, BMP/Nodal, and FGF-signaling pathways are involved in the transcriptional activation of Brachyury. We discuss the molecular mechanisms of Brachyury secondary function in the context of the dorsal-ventral (D-V) inversion theory and the aboral-dorsalization hypothesis. Although the scope of this review requires some degree of oversimplification of Brachyury function, it is beneficial to facilitate studies on the notochord formation, a central evolutionary developmental biology problem in the history of metazoan evolution, pointed out first by Alexander Kowalevsky. © 2012 Wiley Periodicals, Inc.

Takahashi O.,Hiroshima University | Kohno Y.,Yokohama National University | Nishio M.,CHPI Institute
Chemical Reviews | Year: 2010

Researchers conducted investigations to reveal evidence from the latest experimental data and high-level ab initio MO calculations regarding the relevance of weak hydrogen bonds in the conformation of organic compounds and bioconjugates. The researchers showed that the gauche or folded conformation prevailed in organic compounds bearing at least an electronegative or π-group in the molecule. Evidence gathered from the investigations revealed that the gauche or folded conformation is preferred to describe the relevance of weak hydrogen bonds in the conformation of organic compounds and bioconjugates. It was demonstrated that weak attractive forces were essential in deciding the conformation of organic compounds and the 3D structure of biomacromolecules. Researchers also gathered evidence that revealed that hydrogen bonds other than the conventional hydrogen bond were ubiquitous.

Sasaki M.,Hiroshima University | Kondo Y.,Hiroshima University | Kawahata M.,Tokushima Bunri University | Yamaguchi K.,Tokushima Bunri University | Takeda K.,Hiroshima University
Angewandte Chemie - International Edition | Year: 2011

Two flavors of selectivity: An enantioselective Meerwein-Ponndorf-Verley- type reduction of alkynoylsilanes by a chiral lithium amide followed by a Brook rearrangement and S E2′ electrophilic substitution provides the title compounds in a one-pot process. In the case of enynoylsilanes, the generated vinylallenes undergo in situ [4+2] cycloaddition to afford highly functionalized polycyclic compounds with unusual facial selectivity. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hammad A.M.,Menoufia University | Watanabe W.,Hiroshima University | Fujii T.,Hiroshima University | Shimamoto T.,Hiroshima University
International Journal of Food Microbiology | Year: 2012

Staphylococci are not part of the normal fish microflora. The presence of staphylococci on fish is an indication of (a) post-harvest contamination due to poor personnel hygiene, or (b) disease in fish. The aim of this study was to determine the prevalence, molecular genetic characteristics, antibiotic resistance and virulence factors of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MR-CoNS) isolated from 200 samples of retail ready-to-eat raw fish (sashimi) collected from the Japanese prefecture of Hiroshima. We characterized 180 staphylococcal strains. A majority of the grocery stores surveyed (92%, 23/25) contained fish contaminated with Staphylococcus species. We recovered 175 S. aureus isolates from 174 (87%, 174/200) samples, with 170 isolates of MSSA. For the MRSA and MR-CoNS, 10 isolates were obtained from 10 samples (5%, 10/200) collected from 10 shops (40%, 10/25) belonging to four supermarket chains. SCCmec typing revealed the presence of a type IV.1 SCCmec cassette in S. warneri isolates, a type II.1 SCCmec cassette in S. haemolyticus isolates and a cassette in methicillin-resistant S. aureus (MRSA) isolates that could not be typed. Molecular typing of two MRSA isolates by spa sequencing and multilocus sequence typing (MLST) identified t1767 and ST8, respectively. Antibiotic resistance genes that confer resistance to aminoglycosides, tetracyclines, β-lactams, macrolides, lincosamides and streptogramin B (MLS B) antibiotics were detected. Genes encoding one or more of the following virulence factors: staphylococcal enterotoxins (seb, and sed), toxic shock syndrome toxin 1 (tst), exfoliative toxin (etaA) were detected in 14.2% (25/175) of S. aureus isolates. The accessory gene regulator (agr) typing of S. aureus isolates revealed that agr type 1 was most prevalent (96.5%, 169/175) followed by type 2 (2.2%, 4/175) and type 3 (1.1%, 2/175). None of the S. aureus isolates carried the Panton-Valentine leucocidin (PVL) encoding genes, lukF-PV and lukS-PV. To the best of our knowledge, this is the first report to show MRSA and MR-CoNS isolated from retail ready-to-eat food in Japan. Our results showed that sashimi is a likely vehicle for transmission of multidrug-resistant and toxigenic staphylococci. © 2012 Elsevier B.V.

Ishihara Y.,Hiroshima University | Itoh K.,Tokushima Bunri University | Ishida A.,Hiroshima University | Yamazaki T.,Hiroshima University
Journal of Steroid Biochemistry and Molecular Biology | Year: 2015

Growing evidence shows that steroid hormones, especially 17b-estradiol (E2), protect neuronal cells by attenuating excess activation of microglia. However, the use of E2 in the clinic is controversial because of its peripheral actions in reproductive organs and its potential to increase risk for endometrial cancer and breast cancer. Selective estrogen-receptor modulators (SERMs) bind to estrogen receptors (ERs), but their effects as ER agonists or antagonists are dependent on the target tissue. SERMs pose very little cancer risk as a result of their anti-estrogen action in reproductive organs, but their action in the brain is not well understood. In this study, we investigated the effects of SERMs tamoxifen (Tam) and raloxifene (Rlx) on microglial activation and subsequent neuronal injury. Tam and Rlx suppressed the increases in proinflammatory cytokines and chemokine expression that were induced by lipopolysaccharide (LPS) in rat primary microglia cultures. The microglial-conditioned media pretreated with Tam or Rlx significantly attenuated cellular injury in SH-SY5Y cells elicited by microglial-conditioned media treated with LPS alone. Rat primary microglia expressed ERa and ERb primarily in the nucleus, and thus we examined the involvement of ERs in the suppressive action of Tam and Rlx on microglial activation using a pure ER antagonist, ICI182,780. Pretreatment with ICI182,780 abolished the suppressive effects of SERMs on microglial activation, as well as their protective action on SH-SY5Y cells. A luciferase assay using a vector with three estrogen response elements (EREs) revealed that Tam and Rlx activated ERE-mediated transcription in rat primary microglia. Taken together, these results suggest that Tam and Rlx suppress microglial activation and subsequent neuronal cell death via an ER-mediated transcription pathway. SERMs could represent a novel therapeutic strategy for disorders of the central nervous system based on their ability to suppress neuroinflammation. © 2014 Elsevier Ltd. All rights reserved.

Shimadzu Corporation and Hiroshima University | Date: 2014-09-24

The present invention provides amass spectrometry method that can achieve analysis with high sensitivity using a matrix additive capable of improving ionization efficiency in mass spectrometry. Amass spectrometry method comprising the steps of: forming a mixed crystal for mass spectrometry on a target plate for mass spectrometry, the mixed crystal comprising a sample to be analyzed, a matrix, and a matrix additive selected from the group consisting of a 2,5-dihydroxybenzoate and a 3,5-dihydroxybenzoate that are represented by the following formula (I): where R represents an alkyl group having 4 to 14 carbon atoms; and irradiating the mixed crystal with laser to detect the sample to be analyzed.

Shimadzu Corporation and Hiroshima University | Date: 2013-03-13

The application is directed to MALDI matrix additives based on 5-alkoxy-2- or -3-hydroxybenzoic acid represented by the following formula (I):

Hiroshima University and Shibaura Institute of Technology | Date: 2010-10-25

The invention provides a magnetic induction system and an operating method for it in which the magnetic force can be made to act deeply and widely in any desired direction. The magnetic induction system of the invention contains multiple magnetic field generation means formed of a superconductive bulk magnet, a drive means for arranging the magnetic field generation means at a desired site and angle, and a drive control means for driving the driving means and controlling the position and the angle of the multiple magnetic field generation means so that a magnetic complex can be inducted to the desired position in a body by the synthetic magnetic field formed by the multiple magnetic field generation means, whereby the magnetic complex is inducted to be concentrated in the cartilage defected part.

Shimadzu Corporation and Hiroshima University | Date: 2015-12-02

The present invention provides a mass spectrometry method using a matrix that is capable of easily and efficiently improving ionization efficiency in mass spectrometry without modifying a molecule to be analyzed, and a matrix for mass spectrometry. A mass spectrometry method using, as a matrix, a 2,4,6-trihydroxyalkylphenone represented by the following general formula (I): The mass spectrometry method as described above, wherein an analysis object is a hydrophobic compound, particularly, a hydrophobic peptide.

Hiroshima University and Shimadzu Corporation | Date: 2013-11-15

The present invention provides a novel compound that makes it possible to improve ionization efficiency of hydrophobic peptide. 5-alkoxy-2- or -3-hydroxybenzoic acid represented by the following formula (I): where R is an alkyl group having 6 to 10 carbon atoms and the substituted carboxyl group and hydroxyl group are ortho or meta to each other. A matrix additive for mass spectrometry, which is represented by the above formula (I). The above additive which is added to a matrix for mass spectrometry selected from the group consisting of -cyano-4-hydroxycinnamic acid, 2,5-dihydroxybenzoic acid, sinapic acid, and 1,5-diaminonaphthalene. The above additive which is used for mass spectrometry of a hydrophobic peptide.

News Article | October 26, 2016
Site: www.eurekalert.org

The African clawed frog's ancestor inherited one set of chromosomes each from two different species and doubled its whole genome some 18 million years ago, according to an international research consortium led by Japanese and American scientists who sequenced the entire genome of the Xenopus laevis for the first time. Scientists hope that the finding will help our understanding of vertebrate evolution, as the vertebrate genome doubled twice 500 million years ago. X. laevis is unusual in that it is a tetraploid species that has four sets of chromosomes, while many organisms, including humans, are diploid and have two sets of chromosomes. How and when this came about has been a topic of debate for some time. One hypothesis is that the tetraploid X. laevis inherited one half of its genetic material from each parent when two diploid ancestral species mated, and the genome of this diploid offspring then doubled, giving rise to a tetraploid organism with twice the number of chromosomes as its ancestors. X. laevis is an essential organism for biological and biomedical research, but the sheer size and complexity of its genome made it difficult for scientists to sequence the genome in its entirety. Sequencing the entire genome would not only be valuable for biological and biomedical research but also provide clues as to the origins of tetraploidy. The researchers sequenced the entire genome of the J (Japan) strain of the frog, which was developed by Hokkaido University scientists, who inbred the animal over 20 years. The strain is genetically homogeneous, giving scientists a big advantage in the sequencing. The US team, led by Dan Rokhsar and Richard Harland at the University of California, Berkeley, used the shotgun method to sequence short fragments of DNA and piece them together like a puzzle. The Japanese team, led by Masanori Taira at the University of Tokyo, sequenced very long fragments of DNA and determined the location of the long DNA on the chromosomes. Akimasa Fukui and his colleagues at Hokkaido University contributed particularly to data analysis and chromosome mapping. This extra step helped to distinguish the separate genome sequences inherited from each ancestral species. It was a challenging idea to analyze the "transposable elements" (segments of DNA that move around the genome) that become fixed or inactive over time, but might be one way of tracing the two ancestral genomes, present as subgenomes in X. laevis. Akira Hikosaka at Hiroshima University and Yoshinobu Uno at Nagoya University (the latter an alumnus of Hokkaido University), tested this idea and discovered that indeed two sets of chromosomes originated from different diploid ancestors. Curiously, the scientists also found that the subgenomes evolved separately in the nucleus, giving rise to shorter S- and longer L-types, the first evidence of animal subgenome evolution. The L-type chromosomes preserved most of the ancestral genetic information, while the S-type showed greater gene loss, deletion and rearrangement. Furthermore, it was suggested that any number of genes were just changing their functions. Scientists believe that two rounds of whole genome duplication 500 million years ago contributed to the emergence of the first vertebrate species and an explosion of diversity in this group. The new findings from the X. laevis genome should improve our understanding of this important event in our evolutionary history. "I'm surprised that our results indicate that the subgenomes of X. laevis are just evolving now," said Akimasa Fukui. "I believe that these data will not only help us understand the evolutionary aspect of vertebrates, but through frog research, also lead to applications in regenerative therapy."

After the Great East Japan Earthquake, information systems that can achieve "disaster recovery" to recover from loss of information due to large-scale disasters as well as "business continuity plans" that enable quick continuation of services in the aftermath of disasters have been gathering attention in Japan. However, even though strengthening of facilities and formulation of procedures have been carried out, surveys have shown that the frequency that disaster exercises based on plans formulated using the constructed disaster recovery systems are implemented is low. This evaluation platform assumes the occurrence of multiple, simultaneous disasters including earthquakes and communication failure due to damaged communication infrastructure, thereby making it possible to conduct training for various disaster scenarios. Through this training, it will become possible to preemptively evaluate whether or not these wide-area distribution systems will be able to continue providing their services even in times of large-scale disaster. Using functions provided by this evaluation platform will make it possible to quantitatively evaluate the disaster tolerance and fault tolerance of wide-area distribution systems such as the Internet. These research results were presented at the international conference SC15 in Austin, Texas, USA, on November 15, 2015. This project, led by Hiroki Kashiwazaki (Assistant Professor, Osaka University), Ikuo Nakagawa (Visiting Associate Professor, Osaka University), Yoshiaki Kitaguchi (Assistant Professor, Kanazawa University),  Kohei Ichikawa (Associate Professor, Nara Institute of Science and Technology), Tohru Kondo (Associate Professor, Hiroshima University), and Yutaka Kikuchi (Professor, Kochi University of Technology), has pushed forward with research to apply parallel distributed storage technology, which handles storage units provided by multiple computers as a single storage unit, to disaster recovery methods. In this research, the wide-area virtualized environment "distcloud" was constructed, with hubs located at Osaka University, Tohoku University, National Institute of Informatics, Kanazawa University, Kyoto University, Nara Institute of Science and Technology, Hiroshima University, Kochi University of Technology, the University of California, San Diego, as well as data centers in Sapporo and Okinawa. The aim of this research development is to verify the validity of plans for business continuation in times of disaster and quantitatively evaluate the deterioration of the quality of these systems in such a disaster by emulating a failure state of systems during a large-scale disaster in a virtualized environment, thereby improving wide-area systems. Efforts have already been carried out to validate fault tolerance through loss of virtual machines within a single organization, but following a large-scale disaster, various forms of interference occur simultaneously over a wide area. In order to realize more realistic disaster training, this research project has focused on "Software Defined Network (SDN)" technology, which enables users to control network settings by changing software (i.e., programmable), and applied this SDN technology as "technology to destroy the network." The motivation for research and development of the evaluation platform "DESTCloud" is to realize the emulation of more complex interference through the utilization of SDN to cause interference in networks connecting organizations and change the network topology of wide-area systems. Benchmark tests will be carried out until February 2016 in a wide variety of disaster environments through collaboration with corporations developing software for the project. Experimental results will be fed back to these corporations, which are expected to contribute to the improvement of product quality. This project will continue research and development towards the establishment of more practical technology by promoting international standardization regarding SDN control methods of this evaluation platform, establishing a consortium to increase social awareness on network disaster prevention, and increasing the number of hubs.

News Article | November 24, 2016
Site: phys.org

Before the frogs are officially recognized as two separate species, researchers will test if individual frogs from the two groups have unique physical or behavioral features and if they can produce healthy offspring. The project began when researchers at European universities expanded their studies on sex determination and population dynamics in amphibians to include Asian species. The species of tree frog that they chose, Hyla japonica, is found throughout Japan, the Korean peninsula, eastern China, and eastern Russia. Collaborators around the world began sending genetic samples from local frog populations to discover their evolutionary relationships. The data revealed evolutionarily distinct groups of frogs in Japan, the Korean peninsula, and eastern Russia. Ancestors of the modern frog populations likely traveled either into or out of Japan by two separate routes: from the North on a chain of islands between Russia and Japan, and from the South along a land bridge on the Philippine Sea Plate between South Korea and Japan. Japanese H. japonica populations may have been isolated into separate East and West groups. Researchers are exploring this possibility in more detail with an ongoing research project led by Ikuo Miura, PhD, an Associate Professor in Amphibian Research Center at Hiroshima University. The same separation between East and West Japan is known in other species of frogs and skinks. Miura explains that the scientific community has no definitive information about exactly what caused the divide between East and West Japan, but suggests the possibility of the expansion of ancient basin associated with volcanic activity in central Japan. Miura and Yuya Higaki, a fourth-year bachelor's degree student, are currently running genetic analysis on 50 populations of H. japonica from across Japan. They will present their preliminary results on November 26th at the annual conference of the Herpetological Society of Japan. This project is part of Miura's larger research interests in sex determination and its influence on speciation and evolution. If H. japonica is recognized as two separate species, it will be challenging for researchers to decide which species should keep the original name due to the mystery surrounding which population of H. japonica was used for the original species characterization in 1858. The German-British naturalist Albert Gunther named H. japonica after examining a specimen collected years earlier, potentially in 1826, by Philipp Siebold and Heinrich Burger, German botanists and physicians who were among the first Westerners granted official access to Japan. The modern research team visited the British Museum of Natural History to inspect the original specimen, but the location of where Siebold and Burger collected the first H. japonica is recorded only as "Japan." For now, naming the species will remain a historical mystery secondary to the ongoing scientific questions. The current research paper is published in the November 23, 2016 issue of BioMed Central Evolutionary Biology. More information: Dufresnes C, Litvinchuk SN, Borzee A, Jang Y, Li J, Miura I, Perrin N, Stock M. Phylogeography reveals an ancient cryptic radiation in East-Asian tree frogs (Hyla japonica group) and complex relationships between continental and island lineages. BioMed Central Evolutionary Biology. 23 November 2016.

Katoh Y.,Tohoku University | Ikura T.,Tohoku University | Ikura T.,Kyoto University | Hoshikawa Y.,Genome Center | And 6 more authors.
Molecular Cell | Year: 2011

Protein methylation pathways comprise methionine adenosyltransferase (MAT), which produces S-adenosylmethionine (SAM) and SAM-dependent substrate-specific methyltransferases. However, the function of MAT in the nucleus is largely unknown. MafK represses or activates expression of heme oxygenase-1 (HO-1) gene, depending on its heterodimer partners. Proteomics analysis of MafK revealed its interaction with MATIIα, a MAT isozyme. MATIIα was localized in nuclei and found to form a dense network with chromatin-related proteins including Swi/Snf and NuRD complexes. MATIIα was recruited to Maf recognition element (MARE) at HO-1 gene. When MATIIα was knocked down in murine hepatoma cell line, expression of HO-1 was derepressed at both basal and induced levels. The catalytic activity of MATIIα, as well as its interacting factors such as MATIIβ, BAF53a, CHD4, and PARP1, was required for HO-1 repression. MATII serves as a transcriptional corepressor of MafK by interacting with chromatin regulators and supplying SAM for methyltransferases. © 2011 Elsevier Inc.

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.

Tashiro S.,Hiroshima University | Lanctot C.,Charles University
Nucleus | Year: 2015

The eukaryotic genome adopts in the cell nucleus a 3-dimensional configuration that varies with cell types, developmental stages and environmental condition as well as between normal and pathological states. Understanding genome function will therefore require the elucidation of the structure-function relationship of the cell nucleus as a complex, dynamic biological system, referred to as the nucleome. This exciting and timely task calls for a multi-faceted, interdisciplinary and multi-national effort. We propose the establishment of an International Nucleome Consortium to coordinate this effort worldwide. © Satoshi Tashiro and Christian Lactôot.

Mitsunobu S.,University of Shizuoka | Takahashi Y.,Hiroshima University | Terada Y.,Japan Synchrotron Radiation Research Institute | Sakata M.,University of Shizuoka
Environmental Science and Technology | Year: 2010

In this study, we investigated local structures of Sb species in synthetic SbV-coprecipitated and -adsorbed ferrihydrite and goethite, which are common iron(III) oxyhydroxides in environment, at various Sb/Fe molar ratios by extended X-ray absorption fine structure (EXAFS) analyses. The EXAFS analyses showed that SbV is adsorbed on ferrihydrite and goethite by the formation of an inner-sphere surface complex at pH 7.5. In the EXAFS spectra of the coprecipitated ferrihydrite and goethite, some features of the spectra significantly differed from those in the adsorbed samples. The EXAFS simulation indicated that the difference is due to the larger coordination number of the Fe atom to the Sb atom in the coprecipitation samples, indicating a structural incorporation (heterovalent substitution) of SbV into ferrihydrite and goethite. The incorporation of SbV into the structure was also confirmed in natural iron(III) oxyhydroxides in contaminated soil near an Sb mine tailing using μ-EXAFS. This study directly provided the first evidence for the structural incorporation of SbV into the iron(III) oxide structure. Our findings are important for understanding the fate of Sb in the aquatic environment because the behavior of the elements incorporated into solids by such a substitution is not greatly influenced by aquatic factors such as the pH and ionic strength because of isolation of the incorporated metal(loid) ions from the aqueous phase. © 2010 American Chemical 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.

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

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

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.

Tsuchiya Y.,Hiroshima University | Asano T.,Hiroshima University | Nakayama K.,Tohoku University | Kato T.,Kyoto University | And 2 more authors.
Molecular Cell | Year: 2010

Proinflammatory cytokines activate NF-κB using the IκB kinase (IKK) complex that phosphorylates inhibitory proteins (IκBs) at N-terminal sites resulting in their ubiquitination and degradation in the cytoplasm. Although ultraviolet (UV) irradiation does not lead to IKK activity, it activates NF-κB by an unknown mechanism through IκBα degradation without N-terminal phosphorylation. Here, we describe an adaptor function of nuclear IKKβ in UV-induced IκBα degradation. UV irradiation induces the nuclear translocation of IκBα and association with IKKβ, which constitutively interacts with β-TrCP through heterogeneous ribonucleoprotein-U (hnRNP-U) leading to IκBα ubiquitination and degradation. Furthermore, casein kinase 2 (CK2) and p38 associate with IKKβ and promote IκBα degradation by phosphorylation at C-terminal sites. Thus, nuclear IKKβ acts as an adaptor protein for IκBα degradation in UV-induced NF-κB activation. NF-κB activated by the nuclear IKKβ adaptor protein suppresses anti-apoptotic gene expression and promotes UV-induced cell death. © 2010 Elsevier Inc.

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.

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.

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

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

Osaka I.,Hiroshima University | Osaka I.,Japan Science and Technology Agency | Shimawaki M.,Hiroshima University | Mori H.,Hiroshima University | And 4 more authors.
Journal of the American Chemical Society | Year: 2012

We report the synthesis and characterization of a novel donor-acceptor semiconducting polymer bearing naphthobisthiadiazole (NTz), a doubly benzothiadiazole (BTz)-fused ring, and its applications to organic field-effect transistors and bulk heterojunction solar cells. With NTz's highly π-extended structure and strong electron affinity, the NTz-based polymer (PNTz4T) affords a smaller bandgap and a deeper HOMO level than the BTz-based polymer (PBTz4T). PNTz4T exhibits not only high field-effect mobilities of ∼0.56 cm 2/(V s) but also high photovoltaic properties with power conversion efficiencies of ∼6.3%, both of which are significantly high compared to those for PBTz4T. This is most likely due to the more suitable electronic properties and, importantly, the more highly ordered structure of PNTz4T in the thin film than that of PBTz4T, which might originate in the different symmetry between the cores. NTz, with centrosymmetry, can lead to a more linear backbone in the present polymer system than BTz with axisymmetry, which might be favorable for better molecular ordering. These results demonstrate great promise for using NTz as a bulding unit for high-performance semiconducting polymers for both transistors and solar cells. © 2012 American Chemical Society.

Watanabe T.,Hiroshima University | Iima M.,Hiroshima University | Nishiura Y.,Tohoku University
Journal of Fluid Mechanics | Year: 2012

We study spontaneous pattern formation and its asymptotic behaviour in binary fluid flow driven by a temperature gradient. When the conductive state is unstable and the size of the domain is large enough, finitely many spatially localized time-periodic travelling pulses (PTPs), each containing a certain number of convection cells, are generated spontaneously in the conductive state and are finally arranged at non-uniform intervals while moving in the same direction. We found that the role of PTP solutions and their strong interactions (collision) are important in characterizing the asymptotic state. Detailed investigations of pulse-pulse interactions showed the differences in asymptotic behaviour between that in a finite but large domain and in an infinite domain. © 2012 Cambridge University Press.

Ito H.,Hokkaido University | Muromoto M.,Hokkaido University | Kurenuma S.,Hokkaido University | Ishizaka S.,Hiroshima University | And 3 more authors.
Nature Communications | Year: 2013

Numerous studies have focused on the mechanical control of solid structures and phase changes in molecular crystals. However, the molecular-level understanding of how macroscopic forces affect the molecules in a solid remains incomplete. Here we report that a small mechanical stimulus or solid seeding can trigger a single-crystal-to-single-crystal transformation from a kinetically isolated polymorph of phenyl(phenyl isocyanide)gold(I) exhibiting blue photoluminescence to a thermodynamically stable polymorph exhibiting yellow emission without the need for heating or solvent. The phase transformation initiates at the location of the mechanical stimulation or seed crystal, extends to adjacent crystals, and can be readily monitored visually by the accompanying photoluminescent colour change from blue to yellow. The transformation was characterized using single crystal X-ray analysis. Our results suggest that the transformation proceeds through self-replication, causing the complex to behave as 'molecular dominoes'. © 2013 Macmillan Publishers Limited. All rights reserved.

Nakazawa T.,Kyoto University | Nakazawa T.,National Taiwan University | Doi H.,Hiroshima University
Oikos | Year: 2012

Climate change has significant impacts on phenology of various organisms in a species-specific manner. Facing this problem, the match/mismatch hypothesis that phenological (a)synchrony with resource availability strongly influences recruitment success of a consumer population has recently received much attention. In this article, we discuss extending the conventional pairwise concept and demonstrate a community module-based approach as an initial step for exploring community consequences of species-specific phenological shifts caused by climate change. Our multispecies match/mismatch perspective leads to the prediction that phenological (a)synchrony among interacting species critically affects not only population recruitment of species but also key dynamical features of ecological communities such as trophic cascades, competitive hierarchies, and species coexistence. Explicit identification and consideration of species relationships is therefore desirable for a better understanding of seasonal community dynamics and thus community consequences of climate change-induced phenological shifts. © 2011 The Authors. Oikos © 2012 Nordic Society Oikos.

Mitsunobu S.,University of Shizuoka | Takahashi Y.,Hiroshima University | Terada Y.,Japan Synchrotron Radiation Research Institute
Environmental Science and Technology | Year: 2010

The aim of this study was to determine the mechanism of Sb immobilization occurring under reductive soil conditions. In this work, we investigated the distribution and speciation of Sb in reductive soil formed in Sb mine tailing by micro-X-ray absorption near edge structure spectroscopy (μ-XANES) and electron probe microanalyzer (EPMA). EPMA and Fe K-edge μ-XANES analyses of the soil grains indicated that Sb in soil was strongly associated with Fe(III) hydroxides secondarily formed during sedimentation. The Sb concentrations in Sb hotspot were found to be as high as 10-30 wt % (as Sb2O5). Wealso found quartz particles coated by secondary rims bearing Fe(III) hydroxides and Sb. The Sb K-edge μ-XANES analyses of the rimsshowedthatasignificantamountof Sb(III)waspresent only at the surfaces of the rims (thickness <10 μm), indicating that Sb reduction occurred in the reducing soil. The facts suggest that the reduction to Sb(III) in the system can be an important factor for Sb immobilization under reducing conditions, since the Sb(III) sorbs more strongly on Fe(III) hydroxides than Sb(V) and its solubility is also much lower than that of Sb(V) species. © 2010 American Chemical Society.

Koga N.,Hiroshima University | Yamada S.,University of Science and Arts of Iran | Kimura T.,Hiroshima University
Journal of Physical Chemistry C | Year: 2013

Thermal decomposition of Ag2CO3 to Ag2O was investigated to identify the physicochemical events that occur during the reaction and to reveal the interactions that cause the complex kinetic behavior of the reaction. Based on comparative investigation of thermal decomposition behavior of six different commercially available Ag2CO3, a physicogeometrical reaction model of two partially overlapping reaction stages is proposed. The reaction stages involve the formation of a surface product layer and an internal reaction in the as-produced core-shell structure of the reacting particles. Immediately after the formation of the surface product layer, the structural phase transitions of Ag2CO3 to two different high-temperature phases occur. Under these conditions, the thermal decomposition behavior is controlled by the diffusional removal of CO 2 through the surface product layer and/or the increase in internal partial pressure of CO2. The growth of Ag2O particles in the surface product layer produces possible channels for the diffusion of CO2. The relative rates of the formation of the diffusion channels in the surface product layer and the increase in the internal partial pressure determine whether the internal reaction advances at a steady rate or arrests until thermal decomposition of Ag2O of the surface product layer occurs at higher temperatures. The sample and reaction conditions influence the kinetic behavior of different component processes, resulting in the complex thermal decomposition behavior. © 2012 American Chemical Society.

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.

Yoshikawa M.,Hiroshima University | Yamada S.,Japan National Defense Academy | Koga N.,Hiroshima University
Journal of Physical Chemistry C | Year: 2014

Thermal decomposition of Ag2CO3 to form Ag occurs via a multistep reaction, and the reaction pathway varies drastically with the sample and reaction conditions. Understanding this complex reaction behavior has significance today with respect to the formation of Ag nanoparticles via the thermal decomposition of Ag compounds. In this study, the thermal decomposition of three different Ag2CO3 samples that exhibited different reactivities and reaction pathways was investigated via thermal analyses under linearly increasing temperatures and by studying the morphology of the reacting particles. The thermal decomposition was kinetically deconvoluted into four or five partially overlapping reaction steps, in which the contributions of each reaction step to the overall thermal decomposition of Ag2CO 3 to Ag varied as a function of the properties of the sample particles and the heating rate. This complex reaction behavior resulted from the competitive interaction of two physicochemical processes, i.e., sintering of the product particles in the surface product layer and the diffusional removal of the generated gases, during the thermal decomposition of Ag 2CO3 and the intermediate compound Ag2O in the geometrical reaction scheme for a contracting volume induced by surface reactions. The high sintering ability of the Ag2O and Ag formed in the surface product layer causes the complex reaction behaviors during the thermal decomposition and disturbs the formation of Ag nanoparticles. © 2014 American Chemical Society.

Osaka I.,Hiroshima University | Osaka I.,Japan Science and Technology Agency | Osaka I.,RIKEN | Kakara T.,Hiroshima University | And 4 more authors.
Journal of the American Chemical Society | Year: 2013

We show that rational functionalization of the naphthodithiophene core in copolymers based on naphthodithiophene and naphthobisthiadiazole improves the solubility without an alteration of the electronic structure. Surprisingly, the introduction of linear alkyl chains brings about a drastic change in polymer orientation into the face-on motif, which is beneficial for the charge transport in solar cells. As a result, the present polymers exhibit high power conversion efficiencies of up to ∼8.2% in conventional single-junction solar cells. © 2013 American Chemical Society.

Iwamoto T.,Kyoto University | Watanabe Y.,Kyoto University | Takaya H.,Kyoto University | Haino T.,Hiroshima University | And 3 more authors.
Chemistry - A European Journal | Year: 2013

The size- and orientation-selective formation of the shortest-possible C70 peapod in solution and in the solid state by using the shortest structural unit of an "armchair" carbon nanotube (CNT), cycloparaphenylene (CPP), has been studied. [10]CPP and [11]CPP exothermically formed 1:1 complexes with C70, thereby giving the resulting peapods. A van't Hoff plot analysis revealed that the formation of these complexes in 1, 2-dichlorobenzene was mainly driven by entropy, whereas the theoretical calculations suggested that the formation of the complex in the gas phase was predominantly driven by enthalpy. C70 was found to exist in two distinct orientations inside the CPP cavity, namely "lying" and "standing", depending on the specific size of the CPP. The theoretical calculations and the X-ray crystallographic analysis revealed that the interactions between [10]CPP and the short axis of C70 in its lying orientation were isotrop-ic and similar to those observed between [10]CPP and C60. However, the interactions between [11]CPP and C70 in its standing orientation were aniso-tropic, thereby involving the radial deformation of [11]CPP into an ellipsoidal shape. This "induced fit" maximized the van der Waals interactions with the long axis of C70. Theoretical calculations revealed that the deformation occurred readily with low energy loss, thus suggesting that CPPs are highly radially elastic molecules. These results also indicate that the same type of radial deformation should occur in CNT peapods that encapsulate aniso-tropic fullerenes. © 2013 Wiley-VCH Verlag GmbH & Co. KGaA.

Ueda K.,Tohoku University | Takahashi O.,Hiroshima University
Journal of Electron Spectroscopy and Related Phenomena | Year: 2012

Using density functional theory (DFT) methods, we have calculated ionization potential (IP) for K-shell single core hole (SCH) creation and double ionization potential (DIP) for K-shell double core hole (DCH) creation for XH mYH n (X, Y = C, N, O, F, m,n = 0-3), NX 2CXO (X = H or F) and C 60. For these molecules, we estimated the relaxation energies (a measure of the electron density flow to the core-hole site) and the interatomic relaxation energies (a measure of the electron density flow to the two core-hole sites) from the calculated IPs and DIPs. For XH mYH n, we find that the interatomic relaxation energy for the DCH states having two holes at X and Y atoms decreases with the increase in the bond order between X and Y. For NX 2CXO (X = H or F), we find that the substitution of the hydrogen atoms by the fluorine atoms affects the initial-state-bonding shifts but less influences the relaxation energy. For DCH states having two holes at two carbon atoms in C 60, we find that the interatomic relaxation energy decreases with the increase in the hole-hole distance. © 2012 Elsevier B.V. All rights reserved.

Kohyama H.,National Taiwan University | Kimura D.,National Institute of Technology, Ube College | Inagaki T.,Hiroshima University
Nuclear Physics B | Year: 2015

We study the regularization dependence on meson properties and the phase diagram of quark matter by using the two flavor Nambu-Jona-Lasinio model. The model also has the parameter dependence in each regularization, so we explicitly give the model parameters for some sets of the input observables, then investigate its effect on the phase diagram. We find that the location or the existence of the critical end point highly depends on the regularization methods and the model parameters. Then we think that regularization and parameters are carefully considered when one investigates the QCD critical end point in the effective model studies. © 2015.

Osaka I.,Hiroshima University | Akita M.,Hiroshima University | Koganezawa T.,Japan Synchrotron Radiation Research Institute | Takimiya K.,Hiroshima University
Chemistry of Materials | Year: 2012

We report the synthesis, characterization, and field-effect transistor properties of novel semiconducting polymers, PQA2T and PQA3T, incorporating a quinacridone unit, and discuss the structure-property relationships. Comparison of the optical and electrochemical properties between the monomer, repeat unit, and polymer suggests that the effective π-conjugation and the delocalization of HOMO along the backbone are relatively limited. X-ray diffraction studies revealed that the polymers form a π-π stacking with a short distance of 3.6 Å and that the orientational order was enhanced by an increase of molecular weight. The hole mobilities are found to be around 0.2 cm 2 V -1 s -1 and are, interestingly, insensitive to the molecular weight and to the orientational order; the randomly oriented low molecular weight polymer showed similar mobilities to the edge-on oriented high molecular weight polymer. We speculate that the relatively localized HOMO might hinder the charge transport along the backbone, and thus the longer polymer chain is not necessary to facilitate the charge transport. The locally but strongly π-π interacted polymer crystallites seem to be sufficient for the effective charge transport in the QA-based polymer system. These features in the present polymers offer great interest of using QA moieties as the building block for semiconducting polymers and give new insight into the design of a new class of semiconducting polymers. © 2012 American Chemical Society.

Nihon Kohden and Hiroshima University | Date: 2010-09-09

An apparatus for evaluating a vascular endothelial function, includes: a first cuff, to be wound around a first body part of a subject; a second cuff, to be wound around a second body part of the subject; a cuff pressure controller, configured to control a cuff pressure of each of the first and second cuffs, and configured to perform continuous pressure stimulation on the first body part of the subject for a time period by using the first cuff; a cuff pressure detector, configured to detect the cuff pressure of the second cuff from an output of a pressure sensor connected to the second cuff; a pulse wave detector, configured to detect, from the output of the pressure sensor, pulse waves before and after the continuous pressure stimulation is performed; and an analyzer, configured to evaluate the vascular endothelial function by comparing the pulse waves detected before and after the continuous pressure stimulation is performed.

Nihon Kohden and Hiroshima University | Date: 2010-11-24

A vessel wall monitoring apparatus includes: a first detecting unit which detects vessel diameter information based on first biological information obtained from a subject; a first producing unit which differentiates the vessel diameter information detected by the first detecting unit, to produce a vessel diameter function; a second detecting unit which detects blood pressure based on second biological information obtained from the subject; a second producing unit which performs a logarithmic operation on the blood pressure detected by the second detecting unit, to produce a logarithmic blood pressure function; and an outputting unit which produces an impedance model expression by using the vessel diameter function, the logarithmic blood pressure function, and mechanical characteristic values including a stiffness, viscosity, and inertia, and which calculates and outputs at least one of the stiffness, the viscosity, and the inertia based on the impedance model expression.

Hiroshima University, Tokuyama Corporation and Tohoku University | Date: 2013-05-29

[Problems to be Solved] A phoswich radiation detector, which can easily discriminate between detection signals on gamma rays and thermal neutrons, and which can selectively acquire signals on thermal neutrons, is provided. [Means to Solve the Problems] In a phoswich radiation detector having two scintillators and discriminating between thermal neutrons and gamma rays, the detector comprises a scintillator for detecting thermal neutrons, such as LiCaAlF_(6):Eu, which has a light yield of more than 1500 photons/neutron, and a scintillator for detecting gamma rays, which has a permeable end on a shorter wavelength than the light emission wavelength of the thermal neutron scintillator. The scintillator for detecting gamma rays is characterized by being either an organic solid scintillator, such as a plastic scintillator, which does not contain a total amount of 10 mol% or more of elements selected from ^(6)Li, ^(10)B and Gd, or an inorganic single crystal scintillator, such as lithium glass (containing ^(6)Li and Ce) or BGO, which has an effective atomic number Z_(eff) of 30 or larger and which does not contain a total amount of 10 mol% or more of elements selected from ^(6)Li, ^(10)B and Gd.

Hiroshima University, Tohoku University and Tokuyama Corporation | Date: 2011-07-20

[Problems to be Solved] A phoswich radiation detector, which can easily discriminate between detection signals on gamma rays and thermal neutrons, and which can selectively acquire signals on thermal neutrons, is provided. [Means to Solve the Problems] In a phoswich radiation detector having two scintillators and discriminating between thermal neutrons and gamma rays, the detector comprises a scintillator for detecting thermal neutrons, such as LiCaAlF_(6):Eu, which has a light yield of more than 1500 photons/neutron, and a scintillator for detecting gamma rays, which has a permeable end on a shorter wavelength than the light emission wavelength of the thermal neutron scintillator. The scintillator for detecting gamma rays is characterized by being either an organic solid scintillator, such as a plastic scintillator, which does not contain a total amount of 10 mol % or more of elements selected from ^(6)Li, ^(10)B and Gd, or an inorganic single crystal scintillator, such as lithium glass (containing ^(6)Li and Ce) or BGO, which has an effective atomic number Z_(eff )of 30 or larger and which does not contain a total amount of 10 mol % or more of elements selected from ^(6)Li, ^(10)B and Gd.

Nihon Kohden and Hiroshima University | Date: 2012-12-12

An apparatus for evaluating a vascular endothelial function, includes: a cuff pressure controlling unit configured to perform continuous pressure stimulation on a part of a body of a subject for a predetermined time, by using a cuff adapted to be wrapped around the part of the body of the subject; a cuff pressure detecting unit configured to detect a cuff pressure from an output of a pressure sensor connected to the cuff; a pulse wave detecting unit configured to detect a pulse wave from the output of the pressure sensor; and an analyzing unit configured to evaluate the vascular endothelial function by comparing vessel viscoelastic indexes which are obtained from the pulse wave detected in two of zones before, during, and after the pressure stimulation, and which exclude an amplitude of the pulse wave.

Hiroshima University and Nihon Kohden | Date: 2011-03-16

An apparatus for evaluating a vascular endothelial function, includes: a first cuff, to be wound around a first body part of a subject; a second cuff, to be wound around a second body part of the subject; a cuff pressure controller, configured to control a cuff pressure of each of the first and second cuffs, and configured to perform continuous pressure stimulation on the first body part of the subject for a time period by using the first cuff; a cuff pressure detector, configured to detect the cuff pressure of the second cuff from an output of a pressure sensor connected to the second cuff; a pulse wave detector, configured to detect, from the output of the pressure sensor, pulse waves before and after the continuous pressure stimulation is performed; and an analyzer, configured to evaluate the vascular endothelial function by comparing the pulse waves detected before and after the continuous pressure stimulation is performed.

Hiroshima University, Tokuyama Corporation and Tohoku University | Date: 2013-05-29

[Problems to be Solved] A radiation detector, which is improved in the detection efficiency of a photodetector for light emitted by a scintillator, which has excellent long-term operational stability, and which is excellent in time resolution and count rate characteristics, is provided with the use of the scintillator with a short fluorescence lifetime. [Means to Solve the Problems] A radiation detector is constructed by installing an optical wavelength conversion layer, which is composed of, for example, an organic fluorescent substance using polyvinyl toluene as a base material, between a scintillator composed of a fluoride single crystal, such as a Ce-containing LiCaAlF_(6) crystal, and a photodetector having a light entrance window material composed of a transparent glass material such as borosilicate glass. In the radiation detector, the peak wavelength of light emitted by the scintillator is 360 nm or less, and the peak wavelength of light after conversion by the optical conversion layer is 400 nm or more. Preferably, the refractive indexes of the scintillator and the optical wavelength conversion layer are both 1.35 to 1.65.

Hiroshima University and Nihon Kohden | Date: 2013-06-26

An apparatus for evaluating a vascular endothelial function, includes: a cuff pressure controlling unit configured to perform continuous pressure stimulation on a part of a body of a subject for a predetermined time, by using a cuff adapted to be wrapped around the part of the body of the subject; a cuff pressure detecting unit configured to detect a cuff pressure from an output of a pressure sensor connected to the cuff; a pulse wave detecting unit configured to detect a pulse wave from the output of the pressure sensor; and an analyzing unit configured to evaluate the vascular endothelial function by comparing vessel viscoelastic indexes which are obtained from the pulse wave detected in two of zones before, during, and after the pressure stimulation, and which exclude an amplitude of the pulse wave.

Hiroshima University, Tohoku University and Tokuyama Corporation | Date: 2011-07-20

[Problems to be Solved] A radiation detector, which is improved in the detection efficiency of a photodetector for light emitted by a scintillator, which has excellent long-term operational stability, and which is excellent in time resolution and count rate characteristics, is provided with the use of the scintillator with a short fluorescence lifetime. [Means to Solve the Problems] A radiation detector is constructed by installing an optical wavelength conversion layer, which is composed of, for example, an organic fluorescent substance using polyvinyltoluene as a base material, between a scintillator composed of a fluoride single crystal, such as a Ce-containing LiCaAlF_(6 )crystal, and a photodetector having a light entrance window material composed of a transparent glass material such as borosilicate glass. In the radiation detector, the peak wavelength of light emitted by the scintillator is 360 nm or less, and the peak wavelength of light after conversion by the optical conversion layer is 400 nm or more. Preferably, the refractive indexes of the scintillator and the optical wavelength conversion layer are both 1.35 to 1.65.

Nihon Kohden and Hiroshima University | Date: 2015-02-19

A blood pressure measuring apparatus includes a pressure control unit that controls an applied pressure applied to a region of a living body in which a vein and artery exist by a cuff mountable to the region, a detection unit that detects pressure waveforms in which pulse wave components from the region overlap with the applied pressure, and an analysis unit that obtains a respiratory variation on the waveform of artery and a venous pressure based on the pressure waveforms detected by the detection unit through one-time blood pressure measurement. The analysis unit obtains the respiratory variation on the waveform of artery based on data of a first pressure waveform in a first process, and the venous pressure based on data of a second pressure waveform in a second process and the data of the first pressure waveform.

Hiroshima University and Nihon Kohden | Date: 2015-09-02

A blood pressure measuring apparatus (1) includes a pressure control unit (3) that controls an applied pressure applied to a region of a living body in which a vein and artery exist by a cuff (2) mountable to the region, a detection unit (4) that detects pressure waveforms in which pulse wave components from the region overlap with the applied pressure, and an analysis unit (5) that obtains a respiratory variation on the waveform of artery and a venous pressure based on the pressure waveforms detected by the detection unit (4) through one-time blood pressure measurement. The analysis unit (5) obtains the respiratory variation on the waveform of artery based on data of a first pressure waveform in a first process, and the venous pressure based on data of a second pressure waveform in a second process and the data of the first pressure waveform.

Nakano K.,Hiroshima University
Proceedings of the 2012 3rd International Conference on Networking and Computing, ICNC 2012 | Year: 2012

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 approximate string matching for two strings X and Y is a task to find a substring of Y most similar to X. The main contribution of this paper is to show efficient implementations of approximate string matching on the memory machine models. Our best implementation for strings X and Y with length m and n (m < n), respectively, runs in O(mn/w + ml) time units using n threads both on the DMM on the UMM with width w and latency l. © 2012 IEEE.

Shiotani B.,Harvard University | Shiotani B.,Hiroshima University | Nguyen H.,Harvard University | Hakansson P.,Harvard University | And 4 more authors.
Cell Reports | Year: 2013

The ATM- and Rad3-related (ATR) kinase is a master regulator of the DNA damage response, yet how ATR is activated toward different substrates is still poorly understood. Here, we show that ATR phosphorylates Chk1 and RPA32 through distinct mechanisms at replication-associated DNA double-stranded breaks (DSBs). In contrast to the rapid phosphorylation of Chk1, RPA32 is progressively phosphorylated by ATR at Ser33 during DSB resection prior to the phosphorylation of Ser4/Ser8 by DNA-PKcs. Surprisingly, despite its reliance on ATR and TopBP1, substantial RPA32 Ser33 phosphorylation occurs in a Rad17-independent but Nbs1-dependent manner invivo and invitro. Importantly, the role of Nbs1 in RPA32 phosphorylation can be separated from ATM activation and DSB resection, and it is dependent upon the interaction of Nbs1 with RPA. An Nbs1 mutant that is unable to bind RPA fails to support proper recovery of collapsed replication forks, suggesting that the Nbs1-mediated mode of ATR activation is important for the repair of replication-associated DSBs. © 2013 The Authors.

De Freitas L.C.,Hiroshima University | Kaneko S.,Hiroshima University
Ecological Economics | Year: 2012

This study examines whether a causal relation exists between ethanol related innovation and fuel market variables in Brazil. Patent counts were used as proxy for innovation and assessed market variables include ethanol consumption and price, and gasoline price. The study refers to the period 1975-2008. Empirical evidence is formulated with an Autoregressive Distributed Lag (ARDL) model for cointegration and the causality is examined with a multivariate Granger causality test. The results demonstrate a potential causal relation between ethanol innovation and ethanol consumption, evidencing a unidirectional relation from ethanol consumption to patent registers in the studied period. Such a relation indicates that increments in ethanol consumption can potentially stimulate innovation in the sector. Moreover, the ethanol price and the cross-effect of gasoline price have an indirect effect on ethanol innovation. Several questions are raised regarding the yet to be determined factors driving innovation in the sector. Further studies focused on nonmarket aspects, including policy factors, subsidies and international technology spillovers, would potentially elucidate several unanswered questions concerning ethanol innovation in Brazil. © 2011 Elsevier B.V.

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.

Sawai M.,Hiroshima University | Shimamoto T.,China Earthquake Administration | Togo T.,Hiroshima University | Togo T.,Japan National Research Institute for Earth Science and Disaster Prevention
Journal of Structural Geology | Year: 2012

A common view concerning the energetics of seismogenic fault motion is that at least part of the fracture energy is consumed in grain crushing in the fault zone, and that this part may be estimated by grain-size analysis of fault rocks. We address this problem by conducting room-dry friction experiments on Nojima fault gouge at subseismic to seismic slip rates (0.009-1.31m/s) and at normal stresses up to 3.64MPa, and by measuring the BET surface area of the gouge before and after the experiments. Where it cuts granite, the Nojima fault zone has BET surface area of about 65×10 6m 2 per unit fault area (1m 2). Clayey and granular fault gouges, composed mainly of quartz, plagioclase, kaolinite and smectite, were collected from a granitic fault zone at a new outcrop in Funaki, Awaji Island, southwest Japan. Both clayey and granular gouges exhibit dramatic weakening at high slip rates. Specific BET surface areas of clayey and granular gouges decreased with increasing slip rate from 46.0 and 15.4m 2/g before deformation to about 20 and 5m 2/g after deformation (55-70% reduction), respectively. Microstructural observations revealed that grain welding within the slip zones at high slip rates reduced grain surface area. The energetics of seismic fault motion should be examined with broader views taking into account grain crushing, grain welding, decomposition and frictional melting. © 2012 Elsevier Ltd.

Mirshojaeian Hosseini H.,Hiroshima University | Kaneko S.,Hiroshima University
Ecological Indicators | Year: 2011

Monitoring progress toward sustainable development requires the identification of operational indicators that provide manageable units of information on institutional, environmental, economic and social dimensions. This paper is an attempt to develop macro sustainability indicators of selected countries in order to track sustainability in a dynamic manner. Therefore, as a first step, sustainability pillar variables for 131 countries were defined and derived for the period 2000-2007. Three different methods, i.e., standardization, min-max and cyclical techniques, were used to normalize data and finally a principal component analysis (PCA) was applied for weighting selected variables. In the last step, countries were ranked based on their principal components (PCs) and spatially aggregated sustainability was tracked in four dimensions. The paper finds that while progress was observed for the institutional, economic and social dimensions, the environmental conditions deteriorated successively over the studied period. It is concluded that when institutional, environmental and economic pillars are strongly correlated, economic development cannot solely explain environmental deterioration. © 2010 Elsevier Ltd. All rights reserved.

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.

Liao L.,Hiroshima University | Sawa T.,Hiroshima University
International Journal of Adhesion and Adhesives | Year: 2011

The stress wave propagations and stress distributions in epoxy-steel cylinders in which the outside surface of a solid cylinder (steel) is adhered to the inside surface of a hollow cylinder (epoxy resin) subjected to impact push-off loads were analyzed using the finite element method (FEM). The impact push-off loads were applied to epoxy-steel cylinders on a solid cylinder by dropping a weight. The FEM code employed was ANSYS/LS-DYNA. It was found that the maximum principal stress occurs at the upper edge of the interface, where the rupture initiates in epoxy-steel cylinders under the impact push-off loads. Besides, it was also found that the normal stress near the upper edge of the interface increases as the rigidity and the initial impact velocity increase; meanwhile it decreases as the diameter and the height of the solid cylinder increase. The strength of epoxy-steel cylinders increases as the rigidity of the solid cylinder increases, and the diameter and the height of the solid cylinder decrease. In addition, it was observed that the characteristics of the joints subjected to the impact push-off loads are opposite to those of the joints subjected to the static push-off loads. Furthermore, experiments were carried out to measure the strain response of epoxy-steel cylinders subjected to impact and static push-off loads. Fairly good agreements were observed between the numerical and the measured results. © 2011 Elsevier Ltd. All rights reserved.

Ubr11 in the fission yeast Schizosaccharomyces pombe is an evolutionarily conserved ubiquitin ligase functioning in the Arg/N-end rule pathway, which promotes degradation of substrate proteins via the proteasome. Ubr11 recognizes the N-degron sequence in substrates. The primary N-degron contains a destabilization-inducing N-terminal amino acid, which is either a basic (type 1) or bulky hydrophobic (type 2) residue. Dipeptides are known to inhibit proteolytic degradation via the Arg/N-end rule pathway. Here, I examined the potency of some amino acid- or dipeptide-related molecules in their inhibition of Ubr11/N-end rule-mediated degradation. An amide form of l-arginine and l-tryptophan had weak inhibitory activity for type 1 and type 2 substrates, respectively, although the unmodified amino acid monomer and its carboxymethylated ester were ineffective. Among the naturally occurring dipeptides tested, Lys-Leu and Tyr-Leu showed potent inhibitory activity, but their effect was transient, especially at submillimolar concentrations. l-arginine-β-naphthylamide (Arg-βNA) showed stronger activity than several dipeptides for type 1 substrates, but all Lys-Leu, Tyr-Leu, and Arg-βNA caused growth retardation. The inhibitory activity of the l-phenylalanine carbobenzoxy-hydrazide for type 2 substrates was not very strong, but it prolonged the action of Tyr-Leu at low concentrations and, importantly, did not interfere with cell growth. Apart from their utility, these dipeptidomimetics provide a clue for understanding the determinants of recognition by Ubr ubiquitin ligase and further designing novel inhibitors of the Arg/N-end rule pathway. © 2015 Springer-Verlag Wien

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

Lambert R.,International Agency for Research on Cancer | Tanaka S.,Hiroshima University
European Journal of Gastroenterology and Hepatology | Year: 2012

The large and relatively flat colorectal neoplastic lesions called laterally spreading tumors are classified as nonpolypoid despite some mixed patterns with protruding nodules. Large hyperplastic polyps and sessile serrated lesions are non-neoplastic lesions that also have this morphology and may potentially progress to neoplasia. All these large and relatively flat lesions are more frequent in the proximal colon and less conspicuous than polypoid lesions. Their underdiagnosis is a major factor in the failure of colonoscopy to prevent cancer in the proximal colon. The treatment of laterally spreading tumors by endoscopic resection (endoscopic mucosal resection, piecemeal endoscopic mucosal resection, endoscopic submucosal dissection), or by surgery is based on a careful morphologic analysis, taking into account the size and surface with nodules or depression. The technique of endoscopic submucosal dissection should be diffused because it reduces the number of surgical indications. Copyright © 2012 Lippincott Williams &Wilkins.

A transposition graph is a Cayley graph in which each vertex corresponds to a permutation and an edge is placed between permutations iff they differ by exactly one transposition. In this article, we propose an efficient algorithm to find a collection of vertex-disjoint paths connecting a given source vertex s and a given set of destination vertices D. The running time of the algorithm is polynomial in the number of destination vertices, and the resultant path connecting s and each destination is longer than the distance to the destination by at most 16. © 2010 Wiley Periodicals, Inc.

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..

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.

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.

Li G.,Hiroshima University | Kanezashi M.,Hiroshima University | Tsuru T.,Hiroshima University
Catalysis Communications | Year: 2011

Ammonia decomposition in a bimodal catalytic membrane reactor (BCMR) consisting of a Ru/γ-Al2O3/α-Al 2O3 bimodal catalytic support and a hydrogen-selective silica membrane in a single unit was proposed for COx-free hydrogen production in the present study. The bimodal catalytic membrane showed a H 2 permeance of 6.2 × 10-7 mol/(m2 s Pa) at 500 °C, with H2/NH3 and H2/N2 permeance ratios of 200 and 720, respectively. Ammonia conversion was surprisingly enhanced form 45 to 95% at 450 °C in the BCMR after selective H2 extraction. The BCMR showed excellent stability with respect to both gas permeation properties and catalytic activities. © 2011 Elsevier B.V. All rights reserved.

Iwanaga M.,Hiroshima University | Nittono H.,Hiroshima University
Psychophysiology | Year: 2010

To examine how people deal with perceivable consequences of their voluntary actions, we recorded event-related potentials (ERPs) during a self-paced, two-choice random generation task. Sixteen participants were asked to press one of two buttons randomly at a regular but self-selected interval of once per 1-2 s. Each button press produced either a 1000-Hz or 2000-Hz tone, but participants were told that the tones were irrelevant to the task. The button-tone combinations were initially fixed, but in subsequent blocks, a button press infrequently produced the tone associated with the opposite button (p=.15). This cognitively mismatched tone elicited N2, P3, and late positive potential (or positive slow wave) of the ERP and delayed the timing of the next button press. These results suggest that action effects are difficult to ignore and that an action effect that is different from a performer's expectation may cause task disruption. © 2009 Society for Psychophysiological Research.

Noda Y.,Hiroshima University | Koga N.,Hiroshima University
Journal of Physical Chemistry C | Year: 2014

This article describes the physico-geometrical mechanism and overall kinetics for the carbonation of lithium hydroxide monohydrate (LHMH). The constituent reactions of thermal dehydration of LHMH and carbonation of as-produced anhydrous lithium hydroxide (LH) were investigated using thermogravimetry and morphological observations. On the basis of the kinetic information of the constituent reactions, the overall reaction of carbonation of LHMH under conditions of different CO2 concentrations and heating rates was kinetically deconvoluted into separate processes of thermal dehydration and reaction of the as-produced LH with CO2. The kinetic results were interpreted, with reference to the morphological characteristics of the partially reacted sample particles at different reaction stages, as the consecutive processes of the thermal dehydration of LHMH and the carbonation of as-produced LH starting at room temperature, which is geometrically controlled by shrinkage of the reaction interface, LHMH-LH-lithium carbonate (Li 2CO3). The possible existence of a liquid phase at the reaction interface is deduced from the kinetic behavior and microscopic evidence. Variations in overall carbonation behavior as a function of heating rate and CO2 concentration are explained by the changes in the gaseous diffusion behaviors for H2O evolution and CO2 uptake via the surface product layer of Li2CO3 and the evaporation rate of the liquid phase. © 2014 American Chemical Society.

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).

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.

Suzuki Y.,Hiroshima University | Iinuma M.,Hiroshima University | Hofmann H.F.,Hiroshima University | Hofmann H.F.,Chiyoda Corporation
New Journal of Physics | Year: 2012

Quantum mechanics violates Leggett-Garg inequalities because the operator formalism predicts correlations between different spin components that would correspond to negative joint probabilities for the outcomes of joint measurements. However, the uncertainty principle ensures that such joint measurements cannot be implemented without errors. In a sequential measurement of the spin components, the resolution and back-action errors of the intermediate measurement can be described by random spin flips acting on an intrinsic joint probability. If the error rates are known, the intrinsic joint probability can be reconstructed from the noisy statistics of the actual measurement outcomes. In this paper, we use the spin-flip model of measurement errors to analyze experimental data on photon polarization obtained with an interferometric setup that allows us to vary the measurement strength and hence the balance between resolution and back-action errors. We confirm that the intrinsic joint probability obtained from the experimental data is independent of measurement strength, and show that the same violation of the Leggett-Garg inequality can be obtained for any combination of measurement resolution and back-action. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Xu Z.,Hiroshima University | Xu Z.,Donghua University | Nakamura K.,Hiroshima University | Timerbaev A.R.,RAS Vernadsky Institute of Geochemistry and Analytical Chemistry | Hirokawa T.,Hiroshima University
Analytical Chemistry | Year: 2011

Electrokinetic supercharging (EKS) is a powerful and practical method for multifold in-line concentration of various analytes prior to capillary electrophoresis (CE) analysis. However, a problem of insufficient sensitivity has always existed when trace analyte quantification by EKS-CE is a target, especially when coupled with conventional detectors. Normally this requires a greatly increased amount of analyte injected without separation degradation. In this contribution, we have shown that it is possible to substantially improve analyte loading and hence CE method detectability by modifying sample introduction configuration. The volume of sample vial was increased (from typical 500 μL to 17 mL), the common wire electrode was replaced by a ring electrode, and the sample solution was stirred. With these alterations, more analyte ions are accumulated within the effective electric field during electrokinetic injection and then maintained as focused zones due to transient isotachophoresis. The versatility of the customized EKS-CE approach for sample concentration was demonstrated for a mixture of seven rare-earth metal ions with an enrichment factor of 500 000 giving detection limits at or below 1 ng/L. These detection limits are over 100 000 times better than can be achieved by normal hydrodynamic injection, 1000 times better than the sensitivity thresholds of inductively coupled plasma atomic emission spectrometry (ICP-AES), and even close to those of inductively coupled plasma mass spectrometry (ICPMS). © 2010 American Chemical Society.

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.

Kimura R.,Hiroshima University | Yamamoto K.,Hiroshima University
Journal of Cosmology and Astroparticle Physics | Year: 2012

We demonstrate that the general second-order scalar-tensor theories, which have attracted attention as possible modified gravity models to explain the late time cosmic acceleration, could be strongly constrained from the argument of the gravitational Cherenkov radiation. To this end, we consider the purely kinetic coupled gravity and the extended galileon model on a cosmological background. In these models, the propagation speed of tensor mode could be less than the speed of light, which puts very strong constraints from the gravitational Cherenkov radiation. © 2012 IOP Publishing Ltd and Sissa.

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.

Hiyama E.,Hiroshima University
International Journal of Clinical Oncology | Year: 2013

The two main malignant hepatic tumors in children are hepatoblastomas (HBLs) and hepatocellular carcinomas (HCCs). The past two decades have brought significant improvement to the outcomes of children diagnosed with malignant hepatic tumors, especially HBL, due to improvements in diagnosis and treatment. Histological diagnosis is essential for differential diagnosis of these tumors. In surgery, liver resection has become a safe and secure technique because of progress in anatomical knowledge and surgical dissection; also liver transplantation has become widely used for unresectable tumors. Moreover, the introduction of effective chemotherapeutic regimens has significantly improved the survival of children with HBL due to an increase in the number of patients ultimately undergoing tumor resection, and a reduction in the incidence of post-surgical recurrence. These improvements are the result of multicenter cooperative trials conducted by the Japanese Study Group for Pediatric Liver Tumor, the Children's Oncology Group, and the International Childhood Liver Tumor Strategy Group, including work of the German Association of Pediatric Hematology and Oncology. This paper summarizes the results of these studies and calls on the current international collaboration study called the Children's Hepatic Tumors International Collaboration Project to establish global clinical research on childhood hepatic malignant tumors. © 2013 Japan Society of Clinical Oncology.

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.

Narikawa T.,Hiroshima University | Yamamoto K.,Hiroshima University
Journal of Cosmology and Astroparticle Physics | Year: 2012

We present a new test of the modified gravity endowed with the Vainshtein mechanism with the density profile of a galaxy cluster halo observed through gravitational lensing. A scalar degree of freedom in the galileon modified gravity is screened by the Vainshtein mechanism to recover Newtonian gravity in high-density regions, however it might not be completely hidden on the outer side of a cluster of galaxies. Then the modified gravity might yield an observational signature in a surface mass density of a cluster of galaxies measured through gravitational lensing, since the scalar field could contribute to the lensing potential. We investigate how the transition in the Vainshtein mechanism affects the surface mass density observed through gravitational lensing, assuming that the density profile of a cluster of galaxies follows the original Navarro-Frenk-White (NFW) profile, the generalized NFW profile and the Einasto profile. We compare the theoretical predictions with observational results of the surface mass density reported recently by other researchers. We obtain constraints on the amplitude and the typical scale of the transition in the Vainshtein mechanism in a subclass of the generalized galileon model. © 2012 IOP Publishing Ltd and Sissa Medialab srl.

Okada M.,Hiroshima University
Thoracic Surgery Clinics | Year: 2013

Sublobar resection is a compromise for patients with insufficient lung function. Recently small lung cancers are usually detected at the early stage, but sublobar resection in patients who can tolerate lobectomy is not yet standard treatment. Although a few old studies showed higher rates of local recurrence and a poorer prognosis after sublobar resection compared with lobectomy, most have indicated promising outcomes after sublobar resection. Large-scale, randomized, controlled multicenter trials are ongoing in the United States and Japan, the results of which could create revolutionary changes in general thoracic surgery. This article reviews the literature on surgical outcomes of radical sublobar resection. © 2013 Elsevier Inc.

Takezawa A.,Hiroshima University | Kitamura M.,Hiroshima University
Journal of Lightwave Technology | Year: 2012

Optimal cross-sectional shapes of whispering-gallery ring resonators with prescribed emission wavelength and resonance mode are generated using topology optimization based on the finite element method. The two critical performance indices, the quality factor (Q factor) and mode volume of a resonator, are treated as the objective functions in the optimization. In our numerical study, characteristics of optimal configurations are identified and analyzed. Since the Q factor and mode volume have a trade-off relationship, i.e., an increasing Q factor increases mode volume, a Pareto-optimal set of solutions can be identified under certain device specifications. These configurations achieve better performances than existing shapes in producing both a high Q factor and low mode volume. Copyright © 2011 IEEE.

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.

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.

Mirshojaeian Hosseini H.,Hiroshima University | Kaneko S.,Hiroshima University
Ecological Indicators | Year: 2012

Since the Brundtland report, most governments have committed themselves to sustainable development. For this purpose, different global and national organizations and institutions have tried to find the relationships, and especially causalities, between sustainability pillars, which are interesting for them from a policy point of view. With respect to their findings, some questions need to be answered before appropriate policies can be formulated. Are causalities between sustainability pillars global stylized facts or regional phenomena? Can countries with different characteristics follow the same rules, or are causalities between the pillars sensitive to the regional and intrinsic features of countries? Using principal component analysis for the construction of sustainability indicators and the Granger causality model (GMM approach) for testing the causalities between sustainability pillars in different samples, this study finds that causal patterns among the pillars of sustainability are completely sensitive to the characteristics of the countries that are grouped. Therefore, it is recommended that researchers concentrate more on homogeneous case studies and avoid generalizations of causal relationships between sets of heterogeneous countries. © 2011 Elsevier Ltd.

Fukuoka H.,Hiroshima University | Tomomitsu Y.,Hiroshima University | Inumaru K.,Hiroshima University
Inorganic Chemistry | Year: 2011

A new binary barium germanide BaGe 3 was prepared by high-pressure and high-temperature reactions using a Kawai type multi-anvil press. It crystallizes in a hexagonal unit cell with a = 6.814(1) Å, c = 5.027(8) Å, and V = 202.2(5) Å 3 (the space group P6 3/mmc, No. 194). The unit cell contains two layers along the c axis composed of Ba atoms and Ge 3 triangular units. The triangular units stack along the c axis to form 1D columns in which the adjacent Ge 3 units turn to opposite directions. The columns, therefore, can be described as the face-sharing stacking of elongated Ge 6 octahedra. Each Ba atom is surrounded by six columns. BaGe 3 is metallic and shows superconductivity at 4.0 K. The band structure calculations revealed that there are four conduction bands mainly composed of Ge 4p and Ba 5d orbitals. From Fermi surface analysis, we confirmed that three of them have a large contribution of Ge 4pz orbitals in the vicinity of the Fermi level and show a simple 1D appearance. The remaining one contains Ge 4px, 4py, and Ba 5d contributions and shows a 2D property. © 2011 American Chemical Society.

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.

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.

Furukawa T.,Hiroshima University | Takahashi Y.,Hiroshima University
Atmospheric Chemistry and Physics | Year: 2011

Atmospheric aerosols have both a direct and an indirect cooling effect that influences the radiative balance at the Earth's surface. It has been estimated that the degree of cooling is large enough to weaken the warming effect of carbon dioxide. Among the cooling factors, secondary organic aerosols (SOA) play an important role in the solar radiation balance in the troposphere as SOA can act as cloud condensation nuclei (CCN) and extend the lifespan of clouds because of their high hygroscopic and water soluble nature. Oxalic acid is an important component of SOA, and is produced via several formation pathways in the atmosphere. However, it is not certain whether oxalic acid exists as free oxalic acid or as metal oxalate complexes in aerosols, although there is a marked difference in their solubility in water and their hygroscopicity. We employed X-ray absorption fine structure spectroscopy to characterize the calcium (Ca) and zinc (Zn) in aerosols collected at Tsukuba in Japan. Size-fractionated aerosol samples were collected for this purpose using an impactor aerosol sampler. It was shown that 10-60% and 20-100% of the total Ca and Zn in the finer particles (<2.1 μm) were present as Ca and Zn oxalate complexes, respectively. Oxalic acid is hygroscopic and can thus increase the CCN activity of aerosol particles, while complexes with various polyvalent metal ions such as Ca and Zn are not hygroscopic, which cannot contribute to the increase of the CCN activity of aerosols. Based on the concentrations of noncomplexed and metal-complexed oxalate species, we found that most of the oxalic acid is present as metal oxalate complexes in the aerosols, suggesting that oxalic acid does not always increase the hygroscopicity of aerosols in the atmosphere. Similar results are expected for other dicarboxylic acids, such as malonic and succinic acids. Thus, it is advisable that the cooling effect of organic aerosols should be estimated by including the information on metal oxalate complexes and metal complexes with other dicarboxylic acids in aerosols. © 2011 Author(s).

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.

Oohashi K.,Hiroshima University | Hirose T.,Japan Agency for Marine - Earth Science and Technology | Shimamoto T.,Hiroshima University
Journal of Structural Geology | Year: 2011

Carbonaceous materials often concentrate in fault zones developed in pelitic rocks. Among carbonaceous minerals, graphite is known as a lubricant and possibly plays a key role in frictional properties of the fault. Graphite reported from slip localized zones suggests that graphitization can occur during seismogenic fault motion. Thus, we performed friction experiments on amorphous carbon and graphite to investigate how graphite forms in association with fault motion and how these carbonaceous minerals affect frictional properties of faults. Experiments were done at normal stresses of 0.5-2.8 MPa and slip rates of 50 μm/s to 1.3 m/s in atmospheres of air and N2 gas, using rotary-shear apparatuses. XRD and TEM analyses revealed that graphitization can indeed occur during seismogenic fault motion perhaps due to large shear strain, short-lived flash heating and stress concentration at asperity contacts, even at low temperatures and pressures under anoxic environments. We found large differences in steady-state friction coefficient μss between graphite (μss = 0.1) and amorphous carbon (μss = 0.54) at low slip rate. But amorphous carbon exhibits marked velocity weakening at slip rate above 10 mm/s, and its steady-state friction reduces to the same level as that of graphite at a slip rate of 1.3 m/s. Faults with amorphous carbon are not weak at low slip rates, but they can become dynamically weak to foster fault motion during the generation of large earthquakes. Enriched graphite in fault zones can lubricate at all slip rates even at great depths and should receive more attention. © 2011 Elsevier Ltd.

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.

Takahashi Y.,Hiroshima University | Higashi M.,Hiroshima University | Furukawa T.,Hiroshima University | Mitsunobu S.,University of Shizuoka
Atmospheric Chemistry and Physics | Year: 2011

In the North Pacific, transport and deposition of mineral dust from Asia appear to be one of major sources of iron which can regulate growth of phytoplankton in the ocean. In this process, it is essential to identify chemical species of iron contained in Asian dust, because bioavailability of iron in the ocean is strongly influenced by the solubility of iron, which in turn is dependent on iron species in the dust. Here, we report that clay minerals (illite and chlorite) in the dusts near the source collected at Aksu (western China) can be transformed into ferrihydrite by atmospheric chemical processes during their long-range transport to eastern China (Qingdao) and Japan (Tsukuba) based on the speciation by X-ray absorption fine structure (XAFS) and other methods such as X-ray diffraction and chemical extraction. As a result, Fe molar ratio in Aksu (illite : chlorite : ferrihydrite = 70 : 25 : 5) was changed to that in Tsukuba (illite : chlorite : ferrihydrite = 65 : 10 : 25). Moreover, leaching experiments were conducted to study the change of iron solubility. It was found that the iron solubility for the dust in Tsukuba (soluble iron fraction: 11.8 % and 1.10 % for synthetic rain water and seawater, respectively) was larger than that in Aksu (4.1 % and 0.28 %, respectively), showing that iron in the dust after the transport becomes more soluble possibly due to the formation of ferrihydrite in the atmosphere. Our findings suggested that secondary formation of ferrihydrite during the transport should be considered as one of important processes in evaluating the supply of soluble iron to seawater. © 2011 Author(s).

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.

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.

Hirashima T.,Hiroshima University | Kurayama M.,Hiroshima University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

Learning by problem-posing is a promising way to learn arithmetic or mathematics. We have already developed several interactive learning environments for learning by problem-posing. In this research, we have paid a special attention to "reverse-thinking problems" in arithmetic word problems that can be solved either by addition or subtraction. In the reverse-thinking problems, since "story operation structure" and "calculation operation structure" are different, they require learners to comprehend the relations between problems and solutions more than "forward thinking problems" where "story operation structure" and "calculation operation structure" are the same ones. Based on a learning environment for posing the forward thinking problems developed previously, we have expanded it for reverse thinking problems. This learning environment has been used in a class of fourth grade at an elementary school for eight lesson times. We have also reported the results of this practical use. © 2011 Springer-Verlag Berlin Heidelberg.

Ishikawa N.,Hiroshima University | Kobayashi M.,Hiroshima University
Brain and Development | Year: 2010

Various autoantibodies are detected in patients with acute cerebellar ataxia (ACA). Although an autoimmune process may contribute to the mechanism of ACA, its pathophysiology is not completely understood. We report a girl with recurrent ACA and anti-cardiolipin antibodies. Her cerebral blood flow imaging showed hypoperfusion in the cerebellum, which improved when the anti-cardiolipin antibodies disappeared. Our case suggests that vasculopathy or non-vascular neurotoxicity in the cerebellum caused by antiphospholipid antibodies leads to acute cerebellar ataxia. © 2009 Elsevier B.V.

Ito K.,Hiroshima University | Shimahara H.,Hiroshima University
Journal of the Physical Society of Japan | Year: 2016

We examine the mean field theory of a uniaxial coupled Heisenberg antiferromagnet with two subsystems, one of which consists of strongly interacting small spins and the other consists of weakly interacting large spins. We reanalyze the experimental data of specific heat and magnetic susceptibility obtained by previous authors for the organic compound λ-(BETS)2FeCl4 at low temperatures, where BETS stands for bis(ethylenedithio)tetraselenafulvalene. The model parameters for this compound are evaluated, where the applicability of the theory is checked. As a result, it is found that J1 蠑 J12 蠑 J2, where J1, J2, and J12 denote the exchange coupling constant between π spins, that between 3d spins, and that between π and 3d spins, respectively. At the low-temperature limit, both sublattice magnetizations of the 3d and π spins are saturated, and the present model is reduced to the Schottky model, which successfully explains experimental observations in previous studies. As temperature increases, fluctuations of 3d spins increase, while π spins remain almost saturated. Near the critical temperature, both spins fluctuate significantly, and thus the mean field approximation breaks down. It is revealed that the magnetic anisotropy, which may be crucial to the antiferromagnetic long-range order, originates from J12 rather than from J2 and that the angle between the magnetic easy-axis and the crystal c-axis is approximately 26-27° in the present effective model. © 2016 The Physical Society of Japan.

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.

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.

Namera A.,Hiroshima University | Kawamura M.,Forensic Science Laboratory | Nakamoto A.,Forensic Science Laboratory | Saito T.,Tokai University | Nagao M.,Hiroshima University
Forensic Toxicology | Year: 2015

A number of N-alkyl indole or indazole-3-carbonyl analogs, with modified chemical structures, are distributed throughout the world as synthetic cannabinoids. Like synthetic cannabinoids, cathinone analogs are also abused and cause serious problems worldwide. Acute deaths caused by overdoses of these drugs have been reported. Various analytical methods that can cope with the rapid changes in chemical structures are required for routine analysis and screening of these drugs in seized and biological materials for forensic and clinical purposes. Although many chromatographic methods to analyze each drug have been published, there are only a few articles summarizing these analytical methods. This review presents the various colorimetric detections, immunochemical assays, gas chromatographic–mass spectrometric methods, and liquid chromatographic–mass spectrometric methods proposed for the analysis of synthetic cannabinoids and cathinones. © 2015, Japanese Association of Forensic Toxicology and Springer Japan.

Inoue Y.,Japan Aerospace Exploration Agency | Tanaka Y.T.,Hiroshima University
Astrophysical Journal | Year: 2016

Relativistic jets launched by supermassive black holes, so-called active galactic nuclei (AGNs), are known as the most energetic particle accelerators in the universe. However, the baryon loading efficiency onto the jets from the accretion flows and their particle acceleration efficiencies have been veiled in mystery. With the latest data sets, we perform multi-wavelength spectral analysis of quiescent spectra of 13 TeV gamma-ray detected high-frequency-peaked BL Lacs (HBLs) following one-zone static synchrotron self-Compton (SSC) model. We determine the minimum, cooling break, and maximum electron Lorentz factors following the diffusive shock acceleration (DSA) theory. We find that HBLs have PB Pe ∼ 6.3 × 10-3 and the radiative efficiency ∈rad,jet ∼ 6.7 × 10-4, where PB and Pe is the Poynting and electron power, respectively. By assuming 10 leptons per one proton, the jet power relates to the black hole mass as PjetLEdd ∼ 0.18, where Pjet and LEdd is the jet power and the Eddington luminosity, respectively. Under our model assumptions, we further find that HBLs have a jet production efficiency of ηjet ∼ 1.5 and a mass loading efficiency of ξjet ≳ 5 × 10-2. We also investigate the particle acceleration efficiency in the blazar zone by including the most recent Swift/BAT data. Our samples ubiquitously have particle acceleration efficiencies of ηg ∼ 104.5, which is inefficient to accelerate particles up to the ultra-high-energy-cosmic-ray (UHECR) regime. This implies that the UHECR acceleration sites should not be the blazar zones of quiescent low power AGN jets, if one assumes the one-zone SSC model based on the DSA theory. © 2016. The American Astronomical Society. All rights reserved.

Tsubaki R.,Hiroshima University | Fujita I.,Kobe University
Hydrological Processes | Year: 2010

Inundation disasters, caused by sudden water level rise or rapid flow, occur frequently in various parts of the world. Such catastrophes strike not only in thinly populated flood plains or farmland but also in highly populated villages or urban areas. Inundation of the populated areas causes severe damage to the economy, injury, and loss of life; therefore, a proper management scheme for the disaster has to be developed. To predict and manage such adversity, an understanding of the dynamic processes of inundation flow is necessary because risk estimation is performed based on inundation flow information. In this study, we developed a comprehensive method to conduct detailed inundation flow simulations for a populated area with quite complex topographical features using LiDAR (Light Detection and Ranging) data. Detailed geospatial information including the location and shape of each building was extracted from the LiDAR data and used for the grid generation. The developed approach can distinguish buildings from vegetation and treat them differently in the flow model. With this method, a fine unstructured grid can be generated representing the complicated urban land features precisely without exhausting labour for data preparation. The accuracy of the generated grid with different grid spacing and grid type is discussed and the optimal range of grid spacing for direct representation of urban topography is investigated. The developed method is applied to the estimation of inundation flows, which occurred in the basin of the Shin-minato River. A detailed inundation flow structure is represented by the flow model, and the flow characteristics with respect to topographic features are discussed. Copyright © 2010 John Wiley & Sons, Ltd.

Yasumatsu H.,Hiroshima University | Tanabe S.,Hiroshima University
British Journal of Nutrition | Year: 2010

We have demonstrated previously that Asn-Pro-Trp-Asp-Gln (NPWDQ, amino acids 107-111 of s2-casein) inhibited allergen permeation, such as that demonstrated by ovalbumin, using Caco-2 cells as an in vitro human intestinal epithelial model and in mouse jejunal and ileal loops ex vivo. In the present study, the mechanism underlying this inhibitory activity was examined in Caco-2 cells. Transepithelial resistance value increased in response to the addition of increasing NPWDQ concentrations (10 6-104m), which suggests that this peptide enhanced epithelial barrier function. Next, changes in mRNA expression by the addition of NPWDQ (10 6m) were analysed in Caco-2 cells using the microarray method. NPWDQ up-regulated the expression of the occludin gene in cells, but the level of the genes of the claudin family and zonula occludens-1 (ZO-1) was unchanged. Increased protein expression of occludin, but not of claudin-1 or of ZO-1, was also observed. Therefore, it is suggested that NPWDQ up-regulated the expression of occludin in particular and enforced the tight junction barrier. These data imply that a food-derived peptide can fine-tune the epithelial barrier. © The Authors 2010.

Mukaidani H.,Hiroshima University
Proceedings of the IEEE Conference on Decision and Control | Year: 2014

In this paper, the H2/H control problem with multiple decision makers for stochastic delay systems is considered. The H2/H control problem is defined by reformulating the stochastic bounded real lemma and establishing the worst-case disturbance for the stochastic delay system. Since many decision makers exist, both the Pareto optimality and Nash equilibrium are considered for each player. The solvability conditions of the problem are derived from cross-coupled matrix inequalities. A numerical example demonstrates the validity and usefulness of the proposed strategy set. © 2014 IEEE.

Kawano S.,Hiroshima University | Katayama I.,Hiroshima University | Okazaki K.,Hiroshima University
Geology | Year: 2011

The results of fluid-flow experiments revealed a significant permeability anisotropy in highly sheared serpentinite. Fluid flow parallel to serpentinite foliation is an order of magnitude or more higher than that normal to the foliation at confining pressures as high as ~50 MPa. Although buoyancy is the driving force of upward fluid flow in the mantle, the strong anisotropy in permeability results in preferential fluid migration along the subducting plate interface, where extensive plastic deformation and a strong crystal-preferred orientation are expected to occur. The development of a relatively thin hydrous layer in the mantle wedge is consistent with the occurrence of highly anisotropic fluid migration rather than vertical flow. © 2011 Geological Society of America.

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.

Kashiwabara T.,Hiroshima University | Takahashi Y.,Hiroshima University | Tanimizu M.,Japan Agency for Marine - Earth Science and Technology | Usui A.,Kochi University
Geochimica et Cosmochimica Acta | Year: 2011

The distribution of Mo between seawater and marine ferromanganese oxides has great impacts on concentration and isotopic composition of Mo in modern oxic seawater. To reveal the adsorption chemistry of Mo to ferromanganese oxides, we performed (i) detailed structural analyses of Mo surface complexes on δ-MnO2, ferrihydrite, and hydrogenetic ferromanganese oxides by L3- and K-edge XAFS, and (ii) adsorption experiments of Mo to δ-MnO2 and ferrihydrite over a wide range of pHs, ionic strengths, and Mo concentrations. XAFS analyses revealed that Mo forms distorted octahedral (Oh) inner-sphere complexes on δ-MnO2 whereas it forms a tetrahedral (Td) outer-sphere complex on ferrihydrite. In the hydrogenetic ferromanganese oxides, the dominant host phase of Mo was revealed to be δ-MnO2. These structural information are consistent with the macroscopic behaviors of Mo in adsorption experiments, and Mo concentration in modern oxic seawater can be explained by the equilibrium adsorption reaction on δ-MnO2. In addition, the large isotopic fractionation of Mo between seawater and ferromanganese oxides detected in previous studies can be explained by the structural difference between MoO42- and adsorbed species on the δ-MnO2 phase in ferromanganese oxides. In contrast, smaller fractionation of Mo isotopes on ferrihydrite is due to little change in the Mo local structures during its adsorption to ferrihydrite. The structures of Mo species adsorbed on crystalline Fe (oxyhydr)oxides, goethite, and hematite were also investigated at pH 8 and I=0.70M (NaNO3). Our XAFS analyses revealed that Mo forms inner-sphere complexes on both minerals: Td edge-sharing (46%) and Oh double corner-sharing (54%) for goethite, and Td double corner-sharing (14%) and Oh edge-sharing (86%) for hematite. These structural information, combined with those for amorphous ferrihydrite and δ-MnO2, show the excellent correlation with the magnitude of adsorptive isotopic fractionation of Mo reported in previous studies: the proportion of Oh species or their magnitude of distortion in Mo surface complexes become larger in the order of ferrihydrite

Yokooji T.,Hiroshima University | Hamura K.,Hiroshima University | Matsuo H.,Hiroshima University
Biochemical and Biophysical Research Communications | Year: 2013

The absorption pathway(s) of a representative food allergen, lysozyme, and the mechanisms of lysozyme absorption facilitated by non-steroidal anti-inflammatory drugs were examined by intestinal closed-loop and re-circulating perfusion methods in rats. The absorption rate of fluorescein isothiocyanate (FITC)-labeled lysozyme in the proximal intestine was higher than that for a marker of non-specific absorption, FD-10, and was suppressed by colchicine (endocytosis inhibitor). Aspirin increased the absorption of FITC-lysozyme in the proximal intestine with no effects on tissue accumulation. Diclofenac facilitated FITC-lysozyme absorption, but meloxicam and loxoprofen exerted no effects on absorption. Co-administration of misoprostol (synthetic prostaglandin-E1 analog) with aspirin significantly ameliorated the aspirin-facilitated absorption of FITC-lysozyme to the same level as that seen with controls. Thus, lysozyme absorption was mediated by endocytic and paracellular pathways in the proximal intestine, and was facilitated by aspirin and diclofenac after impairment of the paracellular pathway. Misoprostol may suppress the allergen absorption facilitated by aspirin. © 2013 Elsevier Inc.

Yabuki A.,Hiroshima University | Nishisaka T.,Hiroshima University
Corrosion Science | Year: 2011

Porous polymer films with varying pore sizes were prepared by changing the evaporation time of an organic solvent. A specimen was prepared consisting of porous polymer film containing corrosion inhibitor coated onto carbon steel. The specimens were scratched with a knife-edge, and the polarization resistance was monitored in a sodium chloride solution. An increase in polarization resistance was confirmed, and the films with larger-sized pores demonstrated a higher self-healing capability. © 2011 Elsevier Ltd.

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.

Nagata Y.,Hiroshima University
Cancer Research and Treatment | Year: 2013

Stereotactic body radiation therapy (SBRT) is a newly developed technique currently in clinical use. SBRT originated from stereotactic radiosurgery for intracranial tumors. SBRT has been widely used clinically for lung cancer. The practice of SBRT demands different kinds of patient fixation, breathing control, target determination, treatment planning, and verifications. The history and current standard technique are reviewed. Clinical studies of lung cancer showed high local control rates with acceptable toxicities. Past and on-going clinical trials are reviewed. Copyright. © 2013 by the Korean Cancer Association.

Mukaidani H.,Hiroshima University | Yamamoto T.,Hiroshima University
IET Control Theory and Applications | Year: 2012

This study investigates Nash games for a class of multiparameter singularly perturbed stochastic systems governed by Itô's differential equation with Markov jump parameters. First, in order to obtain Nash equilibrium strategies, cross-coupled stochastic algebraic Riccati equations (CSAREs) are formulated. Moreover, necessary condition for the existence of solution for CSAREs is also developed. It is noteworthy that this is the first time that conditions for the existence of stochastic equilibria have been derived based on the solutions of sets of CSAREs. After establishing an asymptotic structure with positive definiteness for CSAREs solutions, feasible numerical algorithms that are based on Newton's method and the linear matrix inequality (LMI) for solving CSAREs is considered. Finally, the authors provide a numerical example to verify the efficiency of the proposed algorithms. © 2012 The Institution of Engineering and Technology.

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.

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.

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.

Nakajima A.,Hiroshima University | Fujii D.,Hiroshima University
Applied Physics Letters | Year: 2015

The memory operation mechanism in fullerene-containing nanocomposite gate insulators was investigated while varying the kind of fullerene in a polymer gate insulator. It was cleared what kind of traps and which positions in the nanocomposite the injected electrons or holes are stored in. The reason for the difference in the easiness of programming was clarified taking the role of the charging energy of an injected electron into account. The dependence of the carrier dynamics on the kind of fullerene molecule was investigated. A nonuniform distribution of injected carriers occurred after application of a large magnitude programming voltage due to the width distribution of the polystyrene barrier between adjacent fullerene molecules. Through the investigations, we demonstrated a nanocomposite gate with fullerene molecules having excellent retention characteristics and a programming capability. This will lead to the realization of practical organic memories with fullerene-containing polymer nanocomposites. © 2015 AIP Publishing LLC.

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.

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.

Kiyota S.,Hiroshima University | Yamamoto K.,Hiroshima University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We investigate the hypothetical process of gravitational Cherenkov radiation, which may occur in modified gravity theories. We obtain a useful constraint on a modified dispersion relation for propagating modes of gravitational waves, which could be predicted as a consequence of the violation of the Lorentz invariance in modified theories of gravity. The constraint from gravitational Cherenkov radiation and that from direct measurements of the gravitational waves emitted by a compact binary system are complementary to each other. © 2015 American Physical Society.

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.

Xin Y.,Hiroshima University | Nishio K.,Hiroshima University | Saitow K.-I.,Hiroshima University
Applied Physics Letters | Year: 2015

A silicon (Si) quantum dot (QD)-based hybrid inorganic/organic light-emitting diode (LED) was fabricated via solution processing. This device exhibited white-blue electroluminescence at a low applied voltage of 6 V, with 78% of the effective emission obtained from the Si QDs. This hybrid LED produced current and optical power densities 280 and 350 times greater than those previously reported for such device. The superior performance of this hybrid device was obtained by both the prepared Si QDs and the optimized layer structure and thereby improving carrier migration through the hybrid LED and carrier recombination in the homogeneous Si QD layer. © 2015 AIP Publishing LLC.

Cai Z.,Hiroshima University | Harada R.,Hiroshima University | Nakayama Y.,Hiroshima University | Shiono T.,Hiroshima University
Macromolecules | Year: 2010

Copolymerizations of norbornene with propylene and 1-octene were conducted with a series of ansa-fluorenylamidodimethyltitanium complexes, [t-BuNSiMe 2Flu]TiMe 2 (1), [t-BuNSiMe 2(3,6- tBu 2Flu)]TiMe 2 (2), [t-BuNSiMe 2(2,7- tBu 2Flu)]TiMe 2 (3), and [t-BuNSiMe 2(C 29H 36)]TiMe 2 (4; C 29H 36, octamethyloctahydrodibenzofluorenyl), activated by trialkylaluminum-free modified methylaluminoxane. The catalytic systems promoted random copolymerizations in a living manner regardless of the titanium complex used. The activity increased by the introduction of the tBu groups on the Flu ligand, and 4 showed the highest activity for each copolymerization. The comonomer content of the copolymers obtained was controllable in a wide range by changing comonomer feed ratio with these catalytic systems. The linear relationships were observed between the norbornene content and the glass transition temperature of the copolymer, whereas the slopes depended on the titanium complex used. The result suggested that the titanium complexes affected the microstructures of the copolymers produced. The evaluation of the monomer reactivity ratios in the copolymerization of norbornene with 1-octene indicates a preference for the norbornene insertion regardless of the last inserted monomer unit in growing polymer chain in all the catalytic systems. © 2010 American Chemical Society.

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.

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.

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.

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.

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

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

Igawa T.,Hiroshima University | Oumi S.,Section of Agriculture and Forest | Katsuren S.,Okinawa Prefectural Institute of Health and Environment | Sumida M.,Hiroshima University
Heredity | Year: 2013

Isolation by distance and landscape connectivity are fundamental factors underlying speciation and evolution. To understand how landscapes affect gene flow and shape population structures, island species provide intrinsic study objects. We investigated the effects of landscapes on the population structure of the endangered frog species, Odorrana ishikawae and O. splendida, which each inhabit an island in southwest Japan. This was done by examining population structure, gene flow and demographic history of each species by analyzing 12 microsatellite loci and exploring causal environmental factors through ecological niche modeling (ENM) and the cost-distance approach. Our results revealed that the limited gene flow and multiple-population structure in O. splendida and the single-population structure in O. ishikawae were maintained after divergence of the species through ancient vicariance between islands. We found that genetic distance correlated with geographic distance between populations of both species. Our landscape genetic analysis revealed that the connectivity of suitable habitats influences gene flow and leads to the formation of specific population structures. In particular, different degrees of topographical complexity between islands are the major determining factor for shaping contrasting population structures of two species. In conclusion, our results illustrate the diversification mechanism of organisms through the interaction with space and environment. Our results also present an ENM approach for identifying the key factors affecting demographic history and population structures of target species, especially endangered species. © 2013 Macmillan Publishers Limited All rights reserved.

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.

Yabuki A.,Hiroshima University | Okumura K.,Hiroshima University
Corrosion Science | Year: 2012

Multi-layer coatings consisting of superabsorbent and vinyl-ester polymers were applied to carbon steel to prevent corrosion. The polarization resistance of a scratched specimen was monitored in a corrosive solution. The polarization resistance of a 3-layer coating, which consisted of a mixed polymer as the middle layer and a vinyl-ester polymer as the base and top layers, increased with time, resulting in a self-healing corrosion inhibition capability. A film, which consisted of spherical particles, was found on the scratched surface of a substrate. The film may have prevented the diffusion of oxygen to the scratched surface. © 2012 Elsevier Ltd.

Nakajima K.,Hiroshima University | Yaoita Y.,Hiroshima University
Biology Open | Year: 2015

A gene of interest can be efficiently modified using transcription activator-like effector nucleases (TALENs) (Christian et al., 2010; Li et al., 2011). However, if a target gene is essential for development, growth and fertility, use of TALENs with high mutagenic activity in F0 frogs could result in developmental disorders or sterility, which would reduce the number of F1 progeny and make F1 phenotypical analysis difficult. We used the 39 untranslated region of DEADSouth gene (DS-39) of Xenopus tropicalis to solve this problem, because the addition of the DS-39 to mRNA is known to induce primordial germ cell (PGC)-specific expression and reduce the stability in somatic cells of mRNA in Xenopus laevis. At first, we inserted the X. tropicalis DS-39 downstream of the EGFP termination codon and confirmed that the EGFP expression was specifically detected in PGCs for three weeks. Therefore, we inserted the DS-39 downstream of the termination codon of the TALEN coding sequence. The tyrosinase gene was selected as the target gene for TALEN because the bi-allelic mutation of this gene is easily discernible by the albino phenotype. When fertilized eggs were microinjected with TALEN mRNAs fused to the DS-39, their sperm and oocytes had a high rate (84-100%) of target-gene modification in contrast to the lower rate (0-45%) of nucleotide alteration observed in somatic cells. © 2015. Published by The Company of Biologists Ltd.

Nakajima K.,Hiroshima University | Yaoita Y.,Hiroshima University
Biology Open | Year: 2015

Zinc-finger nucleases, transcription activator-like effector nucleases (TALENs) and the CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins) system are potentially powerful tools for producing tailor-made knockout animals. However, their mutagenic activity is not high enough to induce mutations at all loci of a target gene throughout an entire tadpole. In this study, we present a highly efficient method for introducing gene modifications at almost all target sequences in randomly selected embryos. The gene modification activity of TALEN is enhanced by adopting the host-transfer technique. In our method, the efficiency is further improved by injecting TALEN mRNAs fused to the 39UTR of the Xenopus DEADSouth gene into oocytes, which are then transferred into a host female frog, where they are ovulated and fertilized. The addition of the 39UTR of the DEADSouth gene promotes mRNA translation in the oocytes and increases the expression of TALEN proteins to near-maximal levels three hours post fertilization (hpf). In contrast, TALEN mRNAs without this 39UTR are translated infrequently in oocytes. Our data suggest that genomic DNA is more sensitive to TALEN proteins from fertilization to the midblastula (MBT) stage. Our method works by increasing the levels of TALEN proteins during the pre-MBT stages. © 2015. Published by The Company of Biologists Ltd.

Nakajima K.,Hiroshima University | Yaoita Y.,Hiroshima University
Biology Open | Year: 2013

Transcription activator-like effector nucleases (TALENs) are facile and potent tools used to modify a gene of interest for targeted gene knockout. TALENs consist of an N-terminal domain, a DNA-binding domain, and a C-terminal domain, which are derived from a transcription activator-like effector, and the non-specific nuclease domain of FokI. Using Xenopus tropicalis (X. tropicalis), we compared the toxicities and somatic mutation activities of four TALEN architectures in a side-by-side manner: a basic TALEN, a scaffold with the same truncated N- and C-terminal domains as GoldyTALEN, a scaffold with the truncated N- and C-terminal domains and an obligate heterodimeric nuclease domain, and a scaffold with the truncated N- and C-terminal domains and an obligate heterodimeric Sharkey nuclease domain. The strongest phenotype and targeted somatic gene mutation were induced by the injection of TALEN mRNAs containing the truncated N- and C-terminal domains and an obligate heterodimeric nuclease domain. The obligate heterodimeric TALENs exhibited reduced toxicity compared to the homodimeric TALENs, and the homodimeric GoldyTALEN-type scaffold showed both a high activity of somatic gene modification and high toxicity. The Sharkey mutation in the heterodimeric nuclease domain reduced the TALEN-mediated somatic mutagenesis. © 2013, Company of Biologists Ltd. All rights reserved.

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.

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.

Kikkawa T.,Hiroshima University
ICSICT-2010 - 2010 10th IEEE International Conference on Solid-State and Integrated Circuit Technology, Proceedings | Year: 2010

Wireless inter-chip interconnects using impulse-radio based ultra-wideband (IR-UWB) CMOS transmitter and receiver were developed for future 3D integration. Silicon integrated antennas were fabricated on a Si substrate by use of conventional back-end metallization processes. Characteristics of on-chip antennas were investigated in terms of device and material parameters. A single-chip IR-UWB CMOS receiver with an on-chip antenna was also investigated for verifying synchronization and data recovery as well as bit error rates for inter-chip wireless interconnects. The receiver could recover 200 Mbps data from the Gaussian monocycle pulse signal, which was transmitted from an on-chip antenna of the other chip at a distance of 0.5 mm. Bit error rate of 6.89 x 10-9 for the distance of 9 cm was obtained in spurious environment. ©2010 IEEE.

Nishitani K.,Hiroshima University | Kokubu K.,Kobe University
Business Strategy and the Environment | Year: 2012

This paper examines the influence of firms' reductions of greenhouse gas (GHG) emissions on firm value, measured by Tobin's q. If the stockholders/investors regard the reduction of GHG emissions as a form of intangible value, the reduction of GHG emissions will enhance firm value. To prove this relation more precisely, this paper analyzes not only the effect of the reduction of GHG emissions on firm value but also that of the market discipline imposed by the stockholders/investors in terms of the reduction of GHG emissions. Using data on 641 Japanese manufacturing firms in the period 2006-2008, the random effect instrumental variable estimate supports the view that firms with strong market discipline imposed by stockholders/investors are more likely to reduce GHG emissions and, consequently, firms that reduce more GHG emissions are more likely to enhance firm value. © 2011 John Wiley & Sons, Ltd and ERP Environment.

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.

Morita K.,Hiroshima University
Proceedings of the 2012 3rd International Conference on Networking and Computing, ICNC 2012 | Year: 2012

Reversible computing is a paradigm of computation that reflects physical reversibility, and will become important when we develop future computing systems that directly utilize microscopic physical phenomena for logical operations. In this survey we discuss, from a theoretical point of view, how a reversible computer is implemented as a reversible logic circuit, how a reversible logic circuit is composed of reversible logic elements, and how a reversible logic element can be realized in a physically reversible system. We shall see that, in spite of the constraint of reversibility, universal reversible computers can be constructed by very simple reversible primitives, and that in these systems computation is often carried out in a very unique and different manner from conventional computing systems. © 2012 IEEE.

Nakajima K.,Hiroshima University | Nakajima T.,Hiroshima University | Takase M.,Hiroshima University | Yaoita Y.,Hiroshima University
Development Growth and Differentiation | Year: 2012

To generate albino lines of Xenopus tropicalis, we injected fertilized eggs with mRNAs encoding zinc-finger nucleases (ZFNs) targeting the tyrosinase coding region. Surprisingly, vitiligo was observed on the skin of F0 frogs that had been injected with ZFN mRNAs, indicating that both tyrosinase genes in the genome were disrupted in all melanocytes within the vitiligo patches. Mutation analysis using genomic DNA from the skin revealed that two mosaic F0 frogs underwent spatially complex tyrosinase gene mutations. The data implies that the ZFN-induced tyrosinase gene ablations occurred randomly over space and time throughout the entire body, possibly until the young tadpole stage, and that melanocyte precursors lacking functional tyrosinase proliferated and formed vitiligo patches. Several albino X. tropicalis, which are compound heterozygotes for biallelic tyrosinase mutations, were obtained by mating the mosaic F0 frogs. To our knowledge, this is the first report of the albino vertebrates generated by the targeted gene knockout. © 2012 The Authors. Development, Growth & Differentiation © 2012 Japanese Society of Developmental Biologists.

Kato Y.,Hiroshima University | Kawamoto T.,Hiroshima University | Fujimoto K.,Hiroshima University | Noshiro M.,Hiroshima University
Current Topics in Developmental Biology | Year: 2014

Daily physiological and behavioral rhythms are regulated by endogenous circadian molecular clocks. Clock proteins DEC1 (BHLHe40) and DEC2 (BHLHe41) belong to the basic helix-loop-helix protein superfamily, which contains other clock proteins CLOCK and BMAL1. DEC1 and DEC2 are induced by CLOCK:BMAL1 heterodimer via the CACGTG E-box in the promoter and, thereafter, suppress their own expression by competing with CLOCK:BMAL1 for the DNA binding. This negative feedback DEC loop together with the PER loop involving PER and CRY, the other negative clock regulators, maintains the circadian rhythm of Dec1 and Dec2 expression. DEC1 is induced by light pulse and adjusts the circadian phase of the central clock in the suprachiasmatic nucleus, whereas DEC1 upregulation by TGF-β resets the circadian phase of the peripheral clocks in tissues. Furthermore, DEC1 and DEC2 modulate the clock output signals to control circadian rhythms in behavior and metabolism. In addition to the functions in the clocks, DEC1 and DEC2 are involved in hypoxia responses, immunological reactions, and carcinogenesis. These DEC actions are mediated by the direct binding to the E-box elements in target genes or by protein-protein interactions with transcription factors such as HIF-1α, RXRα, MyoD, and STAT. Notably, numerous growth factors, hormones, and cytokines, along with ionizing radiation and DNA-damaging agents, induce Dec1 and/or Dec2 in a tissue-specific manner. These findings suggest that DEC1 and DEC2 play a critical role in animal adaptation to various environmental stimuli. © 2014 Elsevier Inc.

Feedforward control by higher brain centres (termed central command) plays a role in the autonomic regulation of the cardiovascular system during exercise. Over the past 20 years, workers in our laboratory have used the precollicular-premammillary decerebrate animal model to identify the neural circuitry involved in the CNS control of cardiac autonomic outflow and arterial baroreflex function. Contrary to the traditional idea that vagal withdrawal at the onset of exercise causes the increase in heart rate, central command did not decrease cardiac vagal efferent nerve activity but did allow cardiac sympathetic efferent nerve activity to produce cardiac acceleration. In addition, central command-evoked inhibition of the aortic baroreceptor-heart rate reflex blunted the baroreflex-mediated bradycardia elicited by aortic nerve stimulation, further increasing the heart rate at the onset of exercise. Spontaneous motor activity and associated cardiovascular responses disappeared in animals decerebrated at the midcollicular level. These findings indicate that the brain region including the caudal diencephalon and extending to the rostral mesencephalon may play a role in generating central command. Bicuculline microinjected into the midbrain ventral tegmental area of decerebrate rats produced a long-lasting repetitive activation of renal sympathetic nerve activity that was synchronized with the motor nerve discharge. When lidocaine was microinjected into the ventral tegmental area, the spontaneous motor activity and associated cardiovascular responses ceased. From these findings, we conclude that cerebral cortical outputs trigger activation of neural circuits within the caudal brain, including the ventral tegmental area, which causes central command to augment cardiac sympathetic outflow at the onset of exercise in decerebrate animal models. © 2011 The Author. Experimental Physiology © 2012 The Physiological Society.

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. [13] 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 [18]. 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.

Doi H.,Hiroshima University | Takahara T.,Hiroshima University | Tanaka K.,Hiroshima University
PLoS ONE | Year: 2012

Understanding the long-term behavior of radionuclides in organisms is important for estimating possible associated risks to human beings and ecosystems. As radioactive cesium ( 137Cs) can be accumulated in organisms and has a long physical half-life, it is very important to understand its long-term decay in organisms; however, the underlying mechanisms determining the decay process are little known. We performed a meta-analysis to collect published data on the long-term 137Cs decay process in fish species to estimate biological (metabolic rate) and ecological (trophic position, habitat, and diet type) influences on this process. From the linear mixed models, we found that 1) trophic position could predict the day of maximum 137Cs activity concentration in fish; and 2) the metabolic rate of the fish species and environmental water temperature could predict ecological half-lives and decay rates for fish species. These findings revealed that ecological and biological traits are important to predict the long-term decay process of 137Cs activity concentration in fish. © 2012 Doi et al.

Fujiwara K.,Hiroshima University | Yasuda S.,Hiroshima University | Mizuta T.,Hiroshima University
Organometallics | Year: 2014

Commercially available THF solutions of BH3·THF, which contain 0.5 mol % of NaBH4 as a stabilizing reagent for BH3·THF, react with 1 atm of CO2 at room temperature to form trimethoxyboroxine, (MeOBO)3, in 87% yield after 12 h. Since no reaction took place in the absence of NaBH4, NaBH4 was found to work as a promoter or catalyst for the reduction of CO2 with BH3 to the methoxy compound. A similar reaction using HCOONa in place of NaBH4 also gave (MeOBO)3 in comparable yield. © 2014 American Chemical Society.

Takimiya K.,RIKEN | Takimiya K.,Hiroshima University | Osaka I.,RIKEN | Mori T.,RIKEN | And 2 more authors.
Accounts of Chemical Research | Year: 2014

ConspectusThe design, synthesis, and characterization of organic semiconductors applicable to organic electronic devices, such as organic field-effect transistors (OFETs) and organic photovoltaics (OPVs), had been one of the most important topics in materials chemistry in the past decade. Among the vast number of materials developed, much expectation had been placed on thienoacenes, which are rigid and planar structures formed by fusing thiophenes and other aromatic rings, as a promising candidate for organic semiconductors for high-performance OFETs. However, the thienoacenes examined as an active material in OFETs in the 1990s afforded OFETs with only moderate hole mobilities (approximately 0.1 cm2 V-1 s-1). We speculated that this was due to the sulfur atoms in the thienoacenes, which hardly contributed to the intermolecular orbital overlap in the solid state. On the other hand, we have focused on other types of thienoacenes, such as [1]benzothieno[3,2-b][1]benzothiophene (BTBT), which seem to have appropriate HOMO spatial distribution for effective intermolecular orbital overlap. In fact, BTBT derivatives and their related materials, including dinaphtho[2,3-b: 2′,3′-f]thieno[3,2-b]thiophene (DNTT), have turned out to be superior organic semiconductors, affording OFETs with very high mobilities. To illustrate some examples, we have developed 2,7-diphenyl BTBT (DPh-BTBT) that yields vapor-deposited OFETs having mobilities of up to 2.0 cm2 V-1 s-1 under ambient conditions, highly soluble dialkyl-BTBTs (Cn-BTBTs) that afford solution-processed OFETs with mobilities higher than 1.0 cm2 V-1 s-1, and DNTT and its derivatives that yield OFETs with even higher mobilities (>3.0 cm2 V-1 s-1) and stability under ambient conditions. Such high performances are rationalized by their solid-state electronic structures that are calculated based on their packing structures: the large intermolecular orbital overlap and the isotropic two-dimensional electronic structure are the key regardless of the molecular size and substituents on the BTBT and its related thienoacene cores. Along with the discovery of such attracting performances, versatile and practical methods for the synthesis of BTBT and its derivatives, and the π-extended derivatives including DNTT, dianthra[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DATT), and the thienoacenes with two thieno[3,2-b]thiophene moieties, have been developed. In addition, the materials have been recently utilized in sophisticated devices and circuits, including all-printed transistor arrays, flexible circuits on ultrathin plastic substrates, and biomedical applications, underscoring their promise as practical semiconductors for electronic device applications. These exciting results of the present BTBT-based materials are expected to open doors to new horizons of organic semiconductors in terms of practical application and the design and synthesis of far more superior materials. © 2014 American Chemical Society.

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.

Tatsuoka T.,Hiroshima University | Koga N.,Hiroshima University
Journal of the American Ceramic Society | Year: 2012

Effect of water vapor on the thermally induced crystallization of tetragonal ZrO 2in hydrous gel precursor was investigated using TG-DTA under controlled water vapor pressures, p(H 2O). Existence of the temperature region for preliminary nucleation in the region lower than that of the crystallization exothermic peak was identified. The rate of preliminary nucleation was largely enhanced by the atmospheric water vapor, resulting in the increase of number of preexisting nuclei for the subsequent growth and the systematic shift of DTA exothermic peak of crystallization to the lower temperatures with increasing p(H 2O). From a systematic shift of the DTA exothermic peak depending on the annealing time at a constant temperature, the rate behavior of preliminary nucleation under high p(H 2O) was characterized as the constant rate nucleation. By the preannealing treatment in the temperature region of preliminary nucleation under high p(H 2O), the number of preexisting nuclei is nearly saturated without any partial crystallization. From a series of DTA exothermic peaks of crystallization recorded by heating the preannealed samples at different heating rates, the apparent activation energy, E a, for the crystal growth of tetragonal ZrO 2from the preexisting nuclei was estimated to be E a= 187.3 ± 3.8 kJ mol -1. © 2011 The American Ceramic Society.

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.

Kadonishi Y.,Hiroshima University | Deie M.,Hiroshima University | Takata T.,Hiroshima University | Ochi M.,Hiroshima University
Journal of Bone and Joint Surgery - Series B | Year: 2012

We examined whether enamel matrix derivative (EMD) could improve healing of the tendon-bone interface following reconstruction of the anterior cruciate ligament (ACL) using a hamstring tendon in a rat model. ACL reconstruction was performed in both knees of 30 Sprague-Dawley rats using the flexor digitorum tendon. The effect of commercially available EMD (EMDOGAIN), a preparation of matrix proteins from developing porcine teeth, was evaluated. In the left knee joint the space around the tendon-bone interface was filled with 40 μl of EMD mixed with propylene glycol alginate (PGA). In the right knee joint PGA alone was used. The ligament reconstructions were evaluated histologically and biomechanically at four, eight and 12 weeks (n = 5 at each time point). At eight weeks, EMD had induced a significant increase in collagen fibres connecting to bone at the tendon-bone interface (p = 0.047), whereas the control group had few fibres and the tendon-bone interface was composed of cellular and vascular fibrous tissues. At both eight and 12 weeks, the mean load to failure in the treated specimens was higher than in the controls (p = 0.009). EMD improved histological tendon-bone healing at eight weeks and biomechanical healing at both eight and 12 weeks. EMD might therefore have a human application to enhance tendon-bone repair in ACL reconstruction. ©2012 British Editorial Society of Bone and Joint Surgery.

Xie W.,421 Washington Ave SE | Willa K.,ETH Zurich | Wu Y.,421 Washington Ave SE | Hausermann R.,ETH Zurich | And 4 more authors.
Advanced Materials | Year: 2013

The angular and temperature dependence of the field-effect mobility are investigated for p-type DNTT single crystals in a vacuum-gap structure. Temperature-independent transport behavior and weak mobility anisotropy are observed, with the best mobility approaching 10 cm2 V-1 s-1. Structural characterization and simulation suggest exceptionally high-quality and high-purity crystals. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yong T.L.-K.,Hiroshima University | Matsumura Y.,Hiroshima University
Industrial and Engineering Chemistry Research | Year: 2012

The effect of temperature (390-450 °C) and residence time (0.5-10 s) at a pressure of 25 MPa was investigated for lignin conversion in supercritical water (SCW) using a continuous flow apparatus designed to rapidly heat the system to the desired reaction temperature. Conversion of lignin in SCW occurs rapidly, and complete depolymerization can be achieved within a 5 s residence time. A high degree of depolymerization is achieved from rapid heating to supercritical temperatures. In addition, supercritical conditions result in a high yield of solid that does not significantly change with an increase in temperature or residence time. To test the suggested hypothesis that the formation of low molecular weight fragments and cross-linking of these fragments forms higher molecular weight fragments, the yield of char, gaseous products, phenolic compounds (phenol, guaiacol, catechol, o-cresol, m-cresol, and catechol) and aromatic hydrocarbons (benzene, toluene, and naphthalene) were determined. The formation of phenolic compounds at short residence time indicates that ether bonds in lignin are easily degraded under supercritical conditions. A reaction network model was proposed, and the subsequent kinetic parameters for the conversion pathways were determined by assuming a first-order reaction. It is observed that the rate constant of overall lignin conversion obeys Arrhenius behavior. The individual rate constants of each reaction in the network are evaluated to determine conformity to Arrhenius behavior. © 2012 American Chemical Society.

Shinamura S.,Hiroshima University | Osaka I.,Hiroshima University | Miyazaki E.,Hiroshima University | Nakao A.,High Energy Accelerator Research Organization | And 3 more authors.
Journal of the American Chemical Society | Year: 2011

A straightforward synthetic approach that exploits linear- and angular-shaped naphthodithiophenes (NDTs) being potential as new core structures for organic semiconductors is described. The newly established synthetic procedure involves two important steps; one is the chemoselective Sonogashira coupling reaction on the trifluoromethanesulfonyloxy site over the bromine site enabling selective formation of o-bromoethynylbenzene substructures on the naphthalene core, and the other is a facile ring closing reaction of fused-thiophene rings from the o-bromoethynylbenzene substructures. As a result, three isomeric NDTs, naphtho[2,3-b:6,7-b′]dithiophene, naphtho[2,3-b:7,6-b′]dithiophenes, and naphtho[2,1-b:6,5-b′] dithiophene, are selectively synthesized. Electrochemical and optical measurements of the parent NDTs indicated that the shape of the molecules plays an important role in determining the electronic structure of the compounds; the linear-shaped NDTs formally isoelectronic with naphthacene have lower oxidation potentials and more red-shifted absorption bands than those of the angular-shaped NDTs isoelectronic with chrysene. On the contrary, the performance of the thin-film-based field-effect transistors (FETs) using the dioctyl or diphenyl derivatives were much influenced by the symmetry of the molecules; centrosymmetric derivatives tend to give higher mobility (up to 1.5 cm2 V-1 s-1) than axisymmetric ones (∼0.06 cm2 V-1 s-1), implying that the intermolecular orbital overlap in the solid state is influenced by the symmetry of the molecules. These results indicate that the present NDT cores, in particular the linear-shaped, centrosymmetric naphtho[2,3-b:6,7-b′]dithiophene, are promising building blocks for the development of organic semiconducting materials. © 2011 American Chemical Society.

Shigeshiro M.,Hiroshima University | Tanabe S.,Hiroshima University | Suzuki T.,Hiroshima University
Journal of Functional Foods | Year: 2013

Some polyphenols have been shown to promote the tight junction (TJ) barrier in intestinal cells. The present study investigated the ameliorative effects of polyphenols, curcumin, quercetin, naringenin or hesperetin, on experimental colitis with a particular focus on the TJ barrier in mice. Administration of dextran sulphate sodium (DSS) caused severe colon damage, indicated by body weight loss, clinical scores, and colon shortening, and TJ barrier impairment, indicated by FITC-dextran permeability. Supplemental feeding of polyphenols (0.3% (w/w)), curcumin, quercetin, naringenin or hesperetin, partially restored these symptoms although the levels of amelioration differed among the polyphenols tested. Feeding naringenin led to more effective restoration. The feeding of each polyphenol restored the expression of TJ proteins, such as zonula occludens-1, occludin, junctional adhesion molecule-A, and claudin-3, impaired by DSS administration. The colon barrier integrity correlated closely with the level of inflammation. Collectively, supplemental feeding of these polyphenols restores DSS-induced colitis, at least in part, through regulation of the colonic TJ barrier. © 2013 Elsevier Ltd.

Saito M.,Hiroshima University | Matsumoto M.,University of Tokyo
ACM Transactions on Mathematical Software | Year: 2013

This article proposes a type of pseudorandom number generator, Mersenne Twister for Graphic Processor (MTGP), for efficient generation on graphic processessing units (GPUs). MTGP supports large state sizes such as 11213 bits, and uses the high parallelism of GPUs in computing many steps of the recursion in parallel. The second proposal is a parameter-set generator for MTGP, named MTGP Dynamic Creator (MTGPDC). MTGPDC creates up to 232 distinct parameter sets which generate sequences with high-dimensional uniformity. This facility is suitable for a large grid of GPUs where each GPU requires separate random number streams. MTGP is based on linear recursion over the two-element field, and has better high-dimensional equidistribution than the Mersenne Twister pseudorandom number generator. © 2013 ACM.

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.

Ahmed A.M.,Kafr El Sheikh University | Shimamoto T.,Hiroshima University
International Journal of Medical Microbiology | Year: 2013

Avian pathogenic Escherichia coli (APEC) causes extensive mortality in poultry flocks, leading to extensive economic losses. To date, little information is available on the molecular basis of antimicrobial resistance in APEC in Africa. Therefore, the objective of this study was to characterize the virulence and antimicrobial resistance of multidrug-resistant APEC isolated from septicemic broilers in Egypt at the molecular level. Among 91 non-repetitive E. coli isolates, 73 (80.2%) carried three or more of the APEC virulence genes iroN, ompT, iss, iutA, and hlyF. All 73 APEC isolates showed multidrug resistance phenotypes, particularly against ampicillin, tetracycline, spectinomycin, streptomycin, kanamycin, and trimethoprim/sulfamethoxazole. PCR and DNA sequencing identified class 1 and class 2 integrons in 34 (46.6%) and seven (9.6%) isolates, respectively. The β-lactamase-encoding genes, blaTEM-1, blaTEM-104, blaCMY-2, blaOXA-30, blaCTX-M-15, and blaSHV-2; tetracycline resistance genes, tet(A), tet(B), tet(C), tet(D), and tet(E); the plasmid-mediated quinolone resistance genes, qnrA1, qnrB2, qnrS1, and aac(6')-Ib-cr, and florfenicol resistance gene, floR, were also identified in 69 (94.5%), 67 (91.8%), 47 (64.4%), and 13 (17.8%) isolates, respectively. To the best of our knowledge, this is the first report of molecular characterization of antimicrobial resistance in APEC strains from Africa. © 2013 Elsevier GmbH.

Su-Myat,Hiroshima University | Koike K.,Hiroshima University
Harmful Algae | Year: 2013

A red tide composed mainly of two Prorocentrum species was found near Kadan Island, southern Myanmar coast, on March 14, 2012. This is the first record of a red tide in the Myanmar coastal area. The red tide included three different harmful dinoflagellates: Prorocentrum rhathymum, Prorocentrum shikokuense and Alexandrium affine. Strains of these species were successfully cultured and examined with detailed morphological observation and DNA (28S rRNA gene) analyses. The strains were subjected to growth experiments under different temperatures to understand their growth capabilities. The experiments were carried out at four different temperature regimes (15, 20, 25 and 30. °C). A. affine exhibited low tolerance for the low temperature regime (15. °C), despite records of its presence in northern temperate regions, indicating this strain is adapted to the tropical environment in Myanmar. P. rhathymum and P. shikokuense exhibited broad tolerance to all given temperature ranges and showed high division rates, providing the physiological basis to form red tides. © 2013 Elsevier B.V.

Shimada I.,Hiroshima University
Designs, Codes, and Cryptography | Year: 2013

Let q be a power of a prime integer p, and let X be a Hermitian variety of degree q + 1 in the n-dimensional projective space. We count the number of rational normal curves that are tangent to X at distinct q + 1 points with intersection multiplicity n. This generalizes a result of Segre on the permutable pairs of a Hermitian curve and a smooth conic. © 2012 Springer Science+Business Media, LLC.

Amakawa S.,Hiroshima University
2014 Asia-Pacific Microwave Conference Proceedings, APMC 2014 | Year: 2014

The gain and the stability of composite amplifiers consisting of a core 2-port amplifier and a lossless reciprocal embedding network is studied theoretically with particular interest in the design of near-fmax amplifiers. Design equations for finding an optimal embedding network that gives the highest MAG (maximum available gain) under a given stability requirement are presented. How such an embedding network could be synthesized is briefly sketched. Copyright 2014 IEICE.

Zschieschang U.,Max Planck Institute for Solid State Research | Yamamoto T.,Hiroshima University | Takimiya K.,Hiroshima University | Kuwabara H.,Nippon Kayaku Co. | And 4 more authors.
Advanced Materials | Year: 2011

Organic transistors and circuits are fabricated directly on the surface of banknotes. The transistors operate with voltages of 3 V and have a field-effect mobility of about 0.2 cm2 V-1s-1. For an array of 100 transistors a yield of 92% is obtained. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA.

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 calix[5]arene 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.

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).

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.

Poumanyvong P.,Hiroshima University | Kaneko S.,Hiroshima University
Ecological Economics | Year: 2010

Despite the relationship between urbanization, energy use and CO2 emissions has been extensively studied in recent years, little attention has been paid to differences in development stages or income levels. Most previous studies have implicitly assumed that the impact of urbanization is homogenous for all countries. This assumption can be questionable as there are many characteristic differences among countries of different levels of affluence. This paper investigates empirically the effects of urbanization on energy use and CO2 emissions with consideration of the different development stages. Using the Stochastic Impacts by Regression on Population, Affluence and Technology (STIRPAT) model and a balanced panel dataset of 99 countries over the period 1975-2005, the findings suggest that the impact of urbanization on energy use and emissions varies across the stages of development. Surprisingly, urbanization decreases energy use in the low-income group, while it increases energy use in the middle- and high-income groups. The impact of urbanization on emissions is positive for all the income groups, but it is more pronounced in the middle-income group than in the other income groups. These novel findings not only help advance the existing literature, but also can be of special interest to policy makers and urban planners. © 2010 Elsevier B.V.

Tanimine N.,Hiroshima University | Ohdan H.,Hiroshima University
OncoImmunology | Year: 2015

Natural killer (NK) cells are potential immune components against hepatocellular carcinoma (HCC) after curative hepatectomy. Patients at high risk of HCC recurrence can be identified by quantifying NK cell licensing. Therefore, therapeutic strategies that manipulate NK cell activity may possibly improve the prognosis of HCC patients. © 2015 Taylor & Francis Group, LLC.

Gene amplification plays a pivotal role in malignant transformation of human cells. A plasmid with both a mammalian replication-initiation region (IR)/origin/replicator and a nuclear matrix-attachment region (MAR) is spontaneously amplified in transfected cells by a mechanism that involves amplification at the extrachromosomal site, followed by amplification at the chromosomal arm, ultimately generating a long homogeneously staining region (HSR). Several observations suggest that replication initiation from IR sequences might mediate amplification. To test this idea, we previously dissected c-myc and DHFR IRs to identify the minimum sequence required to support amplification. In this study, we applied an improved analysis that discriminates between two amplification steps to the ß-globin RepP IR, which contains separate elements already known to be essential for initiation on the chromosome arm. The IR sequence was required at least for the extrachromosomal amplification step. In addition to the vector-encoded MAR, amplification also required an AT-rich region and a MAR-like element, consistent with the results regarding replicator activity on the chromosome. However, amplification did not require the AG-rich tract necessary for replicator activity, but instead required a novel sequence containing another AG-rich tract. The differential sequence requirement might be a consequence of extrachromosomal replication. © 2013 Okada et al.

Tanaka Y.,Hiroshima University | Kunisada E.,Hiroshima University
IEEE Transactions on Magnetics | Year: 2011

A meshless method for transient electromagnetic fields is proposed herein. In this method, wave equations and the Lorentz gauge are discretized using the radial point interpolation method (RPIM) for space and Newmark's β method for time. The proposed method was applied to two typical problems. First, the proposed method was applied to the magnetic field of a square coil, yielding results which agree well with the reference solution. Second, the proposed method was applied to a Hertz dipole and propagation of the electromagnetic field was confirmed. Though the amplitude of the y-component of the magnetic flux density using the proposed method agrees well with that of the exact solution, the amplitude of the z-component of the electric field does not. This is because the amplitude of it is inversely proportional to the distance cubed. However, the potential of the proposed method is confirmed through the numerical examples. © 2011 IEEE.

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.

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.

Takimiya K.,RIKEN | Takimiya K.,Hiroshima University | Osaka I.,RIKEN | Osaka I.,Hiroshima University | Nakano M.,RIKEN
Chemistry of Materials | Year: 2014

Organic electronics has rapidly advanced in the last two decades, owing to the development of semiconducting materials and the innovation of device technologies. One of the critical issues in the materials development, for achieving high performances in the organic devices, is to precisely control their frontier orbitals, i.e., the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels. These energy levels are largely dependent on the chemical structures, and thus to evaluate the electronic properties of representative π-building blocks and to understand their structure-property relationship are of particular importance. In this review, we focus on various π-building blocks for semiconducting polymers and oligomers, especially electron poor heterocycles (acceptor units), and revaluate their electronic structures focusing on the model compounds and the corresponding polymers. A clear difference in the electronic structure is found depending on the chemical structure, which can be explained in terms of "inductive effect" and "resonance effect". We hope that this Review will give new insight into the electronic structure of the semiconducting materials and be an important guideline for the materials design. © 2013 American Chemical Society.

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.

Yoshida H.,Hiroshima University | Kawashima S.,Hiroshima University | Takemoto Y.,Hiroshima University | Okada K.,Hiroshima University | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

One, two, three, four: A copper(I)-phosphine complex catalyzes the diborylation of alkynes and arynes, and the tri- or tetraborylation of propargyl ethers (see scheme; pin=pinacolato). In the latter cases, the C-O bond(s) as well as the C≡C bond are borylated in one pot. Furthermore, a diborylation product serves as an intermediate in the efficient synthesis of ortho-terphenyls with pharmacological activity. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nakano M.,Hiroshima University | Mori H.,Hiroshima University | Shinamura S.,Hiroshima University | Takimiya K.,Hiroshima University
Chemistry of Materials | Year: 2012

New linear-shaped naphtho[2,3-b:6,7-b']-difurans (NDFs) and -selenophenes (NDSs) were synthesized selectively from 3,7-dibromo-2,6-dihydroxynaphthalene and evaluated as organic semiconductors in comparison to corresponding naphtho[2,3-b:6,7-b']dithiophenes (NDTs). Evaluation of the electronic structures of the parent compounds by means of electrochemical and optical measurements clearly indicated that NDT and NDS are quite similar to each other, whereas only NDF has a marked different electronic structure. Thin film devices, including organic field-effect transistors (OFETs) and bilayer photovoltaics (OPVs) with C 60 or C 70 as an acceptor layer, were fabricated with the diphenyl derivatives using vacuum deposition. The thin films were found to be nicely crystalline with the edge-on molecular orientation both on Si/SiO 2 (for OFETs) and ITO substrates (for OPVs). The thin films acted as active semiconducting layer in OFETs with mobility higher than 0.1 cm 2 V -1 s -1 and as a donor layer in OPVs with power conversion efficiencies of up to 2.0%, indicating that the present naphthodichalcogenophenes are potential core structures for the development of new organic semiconductors. © 2011 American Chemical Society.

Haino T.,Hiroshima University | Watanabe A.,Hiroshima University | Hirao T.,Hiroshima University | Ikeda T.,Hiroshima University
Angewandte Chemie - International Edition | Year: 2012

Networking: A bisporphyrin compound possessing an electron-deficient guest moiety assembles in a head-to-tail manner to form polymeric aggregates. Diffusion-ordered NMR spectroscopy and viscosity measurements of the aggregates confirmed the formation of sizable supramolecular polymers. Widely spread nanonetworks (see picture) are formed in solid state. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

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.

Deie M.,Hiroshima University | Ochi M.,Hiroshima University | Adachi N.,Hiroshima University | Shibuya H.,Hiroshima University | Nakamae A.,Hiroshima University
American Journal of Sports Medicine | Year: 2011

Background: The medial patellofemoral ligament (MPFL) is the most important factor for stabilizing the patella and preventing lateral patellar dislocation. Medial patellofemoral ligament reconstruction is an accepted surgical technique to restore patellofemoral stability after lateral patellar dislocation. The authors recently developed a new anatomical MPFL reconstruction method using a cylindrical bone plug and grafted semitendinosus tendon at the anatomical femoral attachment site to mimic the native MPFL. This study evaluated the new technique for stabilizing recurrent patellar dislocation. Hypothesis: This new MPFL reconstruction technique will improve knee symptoms and function with excellent clinical results. Study Design: Case series; Level of evidence, 4. Method: Thirty-one knees were evaluated from 29 cases of recurrent patellar dislocation that were surgically treated using the anatomical MPFL reconstruction technique. The average patient age was 22.2 years (range, 12-34 years); postsurgery follow-up was 2 to 5 years (average, 3.2 years). The patients were clinically evaluated based on the Kujala score, range of motion, and signs of apprehension. The Merchant view was used to measure congruence and tilting angles. Results: Of the 31 knees, 30 showed good clinical results after surgery, while 1 patient showed remaining signs of apprehension. The Kujala score improved from an average of 64 points (range, 35-70) initially to an average of 94.5 points (range, 79-100) at the final follow-up. Range of motion improved for all patients, with an average knee extension of 0° ± 2° and knee flexion of 145° ± 3° at final follow-up. No patellar redislocation was reported. Radiological assessment indicated significant improvement to the congruence angle from 13° ± 4° before surgery to -5° ± 5° at the final follow-up, while the tilting angle went from 8° ± 7° before surgery to 7° ± 4° at the final follow-up. Conclusion: This study demonstrated excellent results using the new procedure for recurrent dislocation of the patella, with instability in only 1 of 31 knees (3.2%). © 2011 The Author(s).

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.

Kisaka S.,Hiroshima University | Kojima Y.,Hiroshima University
Monthly Notices of the Royal Astronomical Society | Year: 2010

We investigate the evolutions of supermassive black hole mass (MBH) and host spheroid mass (Msph) in order to track the history of the MBH-Msph relationship. The typical mass increase in MBH is calculated by a continuity equation and accretion history, which is estimated from the active galactic nucleus luminosity function. The increase in Msph is also calculated by using a continuity equation and a star formation model, which uses observational data for the formation rate and stellar mass function. We find that the black hole to spheroid mass ratio is expected to be substantially unchanged since z ~ 1.2 for high mass objects (MBH > 108.5M and Msph > 1011.3M). In the same redshift range, the spheroid mass is found to increase more rapidly than the black hole mass if Msph > 1011M. The proposed mass-dependent model is consistent with the current available observational data in the MBH-Msph diagram. © 2010 The Authors. Journal compilation © 2010 RAS.

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.

Fujii Y.,Waseda University | Homma K.,Hiroshima University | Homma K.,Ludwig Maximilians University of Munich
Progress of Theoretical Physics | Year: 2011

The observed accelerating universe indicates the presence of Dark Energy which is probably interpreted in terms of an extremely light gravitational scalar field. We suggest a way to probe this scalar field which contributes to optical light-by-light scattering through the resonance in the quasi-parallel collision geometry. As we find, the frequency-shifted photons with the specifically chosen polarization state can be a distinct signature of the scalar-fieldexchange process in spite of the extremely narrow width due to the gravitationally weak coupling to photons. Main emphasis will be placed in formulating a prototype theoretical approach, then showing how the weak signals from the gravitational coupling are enhanced by other non-gravitational effects at work in laser experiments.

Sainz Jr. B.,University of Illinois at Chicago | Barretto N.,University of Illinois at Chicago | Martin D.N.,University of Illinois at Chicago | Hiraga N.,Hiroshima University | And 9 more authors.
Nature Medicine | Year: 2012

Hepatitis C virus (HCV) is a leading cause of liver disease worldwide. With ∼170 million individuals infected and current interferon-based treatment having toxic side effects and marginal efficacy, more effective antivirals are crucially needed. Although HCV protease inhibitors were just approved by the US Food and Drug Administration (FDA), optimal HCV therapy, analogous to HIV therapy, will probably require a combination of antivirals targeting multiple aspects of the viral lifecycle. Viral entry represents a potential multifaceted target for antiviral intervention; however, to date, FDA-approved inhibitors of HCV cell entry are unavailable. Here we show that the cellular Niemann-Pick C1-like 1 (NPC1L1) cholesterol uptake receptor is an HCV entry factor amendable to therapeutic intervention. Specifically, NPC1L1 expression is necessary for HCV infection, as silencing or antibody-mediated blocking of NPC1L1 impairs cell culture-derived HCV (HCVcc) infection initiation. In addition, the clinically available FDA-approved NPC1L1 antagonist ezetimibe potently blocks HCV uptake in vitro via a virion cholesterol-dependent step before virion-cell membrane fusion. Moreover, ezetimibe inhibits infection by all major HCV genotypes in vitro and in vivo delays the establishment of HCV genotype 1b infection in mice with human liver grafts. Thus, we have not only identified NPC1L1 as an HCV cell entry factor but also discovered a new antiviral target and potential therapeutic agent. © 2012 Nature America, Inc. All rights reserved.

Yabuki A.,Hiroshima University | Sakai M.,Hiroshima University
Corrosion Science | Year: 2011

A self-healing corrosion protective coating was developed using TiO2 particles and casein as pH-sensitive organic agents that is also environmentally friendly materials. A film structured of TiO2 particles was formed on a substrate (magnesium alloy) by dip-coating followed by immersion in a casein solution. Casein was inserted and fixed in the particle film by changing the pH of the casein solution. The polarization resistance of the scratched specimen prepared by changing the pH of the solution from 12 to 5 increased with testing time, and a deposited film consisting of TiO2 particles and casein was observed after the test. © 2010 Elsevier Ltd.

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.

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.

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.

Albo J.,Hiroshima University | Wang J.,Hiroshima University | Tsuru T.,Hiroshima University
Journal of Membrane Science | Year: 2014

Thin-film composite reverse osmosis membranes were dried under different membrane pre-treatment procedures and evaluated at increased temperatures by gas separation tests. The obtained permeance and selectivity values indicated the presence of highly-permeable regions in the dry samples of the commercial membranes.Treatment with ethanol-hexane in a solvent exchange process, as well as membrane immersion in t-butanol followed by freeze drying, increased the gas permeance by a factor of 1.8 to 9, and from 1.6 to 3.2, respectively, by comparison with room temperature and oven drying. Nevertheless, a Knudsen-diffusion transport mechanism was dominant after both pre-treatments.The permeation temperature remarkably influenced gas selectivity and permeance, and a maximum He/N2 selectivity occurred at 150°C with considerable high permeance results, which may suggest the use of polyamide membranes as alternative materials for high-temperature separation processes. The temperature-induced changes in the polymer structure and in the transport of compounds can be explained by Knudsen and activated diffusion mechanisms throughout a highly-permeable regions and a dense polyamide matrix, respectively. © 2013 Elsevier B.V.

Albo J.,Hiroshima University | Wang J.,Hiroshima University | Tsuru T.,Hiroshima University
Journal of Membrane Science | Year: 2014

Commercial thin-film composite reverse osmosis (RO) membranes (SWC5, ESPA2 and CPA5) were dried under different membrane pre-treatments and evaluated for isopropanol dehydration at increased temperatures in pervaporation and vapor permeation systems.Water permeance was enhanced in the membranes pre-treated with ethanol-hexane and freeze drying, compared with those membranes dried by room temperature and in an oven. In particular, ethanol-hexane dried samples showed an enhanced water permeance by a factor of 1.7-3.5, depending on the structural characteristics of each membrane.The membranes exhibited stability for up to 25 operation hours in the vapor permeation system. Moreover, the operation temperature was an important factor in determining water and isopropanol permeances. With an increase in temperature, the highly permeable regions, which showed low selectivity, were plugged more rapidly. As a result, the maximum water/isopropanol separation factor was reached at 150°C, α(water/IPA)=284, with a considerably high flux of 5.93kg/(m2h) for a CPA5 high-rejection RO membrane.The induced changes in the polymer morphology and separation performance data were compared to single gas permeation. The results are discussed in terms of membrane swelling, which softens the polymer and decreases the diffusion resistance to molecules in pervaporation by comparison with vapor permeation. © 2013.

To reveal the genome-wide aspects of Xenopus T2 family miniature inverted-repeat transposable elements (MITEs), we performed a systematic search and classification of MITEs by a newly developed procedure. A terminal sequence motif (T2-motif: TTAAAGGRR) was retrieved from the Xenopus tropicalis genome database. We then selected 51- to 1,000-bp MITE candidates framed by an inverted pair of 2 T2-motifs. The 34,398 candidates were classified into possible clusters by a novel terminal sequence (TS)-clustering method on the basis of differences in their short terminal sequences. Finally, 19,242 MITEs were classified into 16 major MITE subfamilies (TS subfamilies), 10 of which showed apparent homologies to known T2 MITE subfamilies, and the rest were novel TS subfamilies. Intra- and inter-subfamily similarities or differences were investigated by analyses of diversity in GC content, total length, and sequence alignments. Furthermore, genome-wide conservation of the inverted pair structure of subfamily-specific TS stretches and their target site sequence (TTAA) were analyzed. The results suggested that some TS subfamilies might include active or at least recently active MITEs for transposition and/or amplification, but some others might have lost such activities a long time ago. The present methodology was efficient in identifying and classifying MITEs, thereby providing information on the evolutionary dynamics of MITEs. © 2009 Springer-Verlag.

Sakane H.,Hiroshima University | Sakane H.,Osaka University | Yamamoto H.,Hiroshima University | Yamamoto H.,Osaka University | And 2 more authors.
Journal of Cell Science | Year: 2010

β-catenin-mediated Wnt signaling is crucial in animal development and tumor progression. The phosphorylation of low-density lipoprotein receptor-related protein 6 (LRP6), a single-span transmembrane Wnt receptor, plays a vital role in this signaling. Dickkopf1 (Dkk1) has been shown to inhibit the Wnt - β-catenin pathway, but the mechanism is not yet clear. Here, evidence is presented that Wnt3a-dependent phosphorylation of LRP6 occurs in the lipid raft and that Dkk1 inhibits the formation of a complex between LRP6 and casein kinase 1γ (CK1γ) by removing LRP6 from the lipid raft. Dkk1 internalized LRP6 in a Rab5-dependent mechanism to prevent phosphorylation mediated by CK1γ. The internalized LRP6 was recycled back in a Rab11-dependent mechanism to the cell-surface membrane, and the recycled LRP6 again responded to Wnt3a and Dkk1. Internalized Dkk1 was trafficked in a Rab7-mediated route and degraded in the lysosome. These results suggest that Dkk1 induces the internalization of LRP6 to suppress its phosphorylation in the lipid raft and allows subsequent recycling of LRP6 so that it can be reused for signaling.

Kanezashi M.,Hiroshima University | Kawano M.,Hiroshima University | Yoshioka T.,Hiroshima University | Tsuru T.,Hiroshima University
Industrial and Engineering Chemistry Research | Year: 2012

Bis(triethoxysilyl)methane (BTESM), which consists of Si-C-Si bonds, was used as a membrane precursor to control the size of amorphous silica networks. The single gas permeation characteristics of hybrid silica membranes were examined to determine the effect of silica precursors on amorphous networks. Pore size distribution, as determined by single gas permeation, suggested that average pore size was in the following order: bis(triethoxysilyl)ethane (BTESE)-derived silica > BTESM-derived silica > tetraethoxysilane (TEOS)-derived silica, due to differences in the minimum units of the silica precursor. The high C 3H 6/C 3H 8 separation performance of BTESM-derived silica membranes in a wide temperature range (50-200 °C) can be due to the control of silica network size by the "spacer" method using a Si-C-Si unit. For example, a BTESM-derived silica membrane showed a high C 3H 6 permeance of 6.32-10 -7 molm -2 s -1 Pa -1 with a C 3H 6/C 3H 8 permeance ratio of 8.8 at 50 °C. The order of C 3H 6 and C 3H 8 permeances of BTESM-derived silica membranes was C 3H 6 > C 3H 8, independent of the number of sol coats and temperature (50-200 °C), although the kinetic diameter of C 3H 6 (d k = 0.45 nm) was reported to be larger than that of C 3H 8 (d k = 0.43 nm). For permeation of hydrocarbons through amorphous silica membranes, it is suggested that the kinetic diameter, which is a minimum equilibrium cross-sectional diameter, is not applicable for effective molecular size, probably because diffusivity depends not only on the minimum cross section but also on molecular length. © 2011 American Chemical Society.

Endo S.,Hiroshima University | Kajimoto T.,Hiroshima University | Shizuma K.,Hiroshima University
Journal of Environmental Radioactivity | Year: 2013

The transfer coefficient (TF) from soil to rice plants of 134Cs and 137Cs in the form of radioactive deposition from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March 2011 was investigated in three rice paddy fields in Minami-Soma City. Rice crops were planted in the following May and harvested at the end of September. Soil cores of 30-cm depth were sampled from rice-planted paddy fields to measure 134Cs and 137Cs radioactivity at 5-cm intervals. 134Cs and 137Cs radioactivity was also measured in rice ears (rice with chaff), straws and roots. The rice ears were subdivided into chaff, brown rice, polished rice and rice bran, and the 134Cs and 137Cs radioactivity concentration of each plant part was measured to calculate the respective TF from the soil. The TF of roots was highest at 0.48 ± 0.10 in the field where the 40K concentration in the soil core was relatively low, in comparison with TF values of 0.31 and 0.38 in other fields. Similar trends could be found for the TF of whole rice plants, excluding roots. The TF of rice ears was relatively low at 0.019-0.026. The TF of chaff, rice bran, brown rice and polished rice was estimated to be 0.049, 0.10-0.16, 0.013-0.017 and 0.005-0.013, respectively. © 2012 Elsevier Ltd.

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.

Harada S.,Hiroshima University | Sekiguchi N.,Hiroshima University | Shimizu N.,Hiroshima University
Nucleic Acids Research | Year: 2011

Amplified genes in cancer cells reside on extrachromosomal double minutes (DMs) or chromosomal homogeneously staining regions (HSRs). We used a plasmid bearing a mammalian replication initiation region to model gene amplification. Recombination junctions in the amplified region were comprehensively identified and sequenced. The junctions consisted of truncated direct repeats (type 1) or inverted repeats (type 2) with or without spacing. All of these junctions were frequently detected in HSRs, whereas there were few type 1 or a unique type 2 flanked by a short inverted repeat in DMs. The junction sequences suggested a model in which the inverted repeats were generated by sister chromatid fusion. We were consistently able to detect anaphase chromatin bridges connected by the plasmid repeat, which were severed in the middle during mitosis. De novo HSR generation was observed in live cells, and each HSR was lengthened more rapidly than expected from the classical breakage/fusion/bridge model. Importantly, we found massive DNA synthesis at the broken anaphase bridge during the G1 to S phase, which could explain the rapid lengthening of the HSR. This mechanism may not operate in acentric DMs, where most of the junctions are eliminated and only those junctions produced through stable intermediates remain. © 2010 The Author(s).

Harada Y.,Hiroshima University | Harada H.,Hiroshima University
Journal of Cellular Biochemistry | Year: 2011

RUNX1/AML1 point mutations have been identified in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) patients. A heterozygous germline mutation of the RUNX1 gene causes a familial platelet disorder with a predisposition to AML. RUNX1 mutations have also been detected with high frequency in minimally differentiated AML M0 subtypes and myelodysplastic/ myeloproliferative neoplasms. Here we propose a new disease category of myelodysplastic neoplasms (MDN) consisting of MDS refractory anemia with excess blasts and AML with myelodysplasia-related changes, including therapy-related cases. RUNX1 mutations have been detected in about 20% of patients with "MDN". Among the MDN cases, histories of radiation exposure, therapy-related myeloid neoplasms after successful treatment for acute promyelocytic leukemia, and leukemic transformation of myeloproliferative neoplasms have been reported to have a strong association with RUNX1 mutations. The mutations occur in a normal, a receptive, or a disease-committed hematopoietic stem cell. It is suspected that the "MDN" phenotypes are defined by the RUNX1 mutations in addition to some other abnormalities. © 2010 Wiley-Liss, Inc.

Memon M.A.,Institute for Global Environmental Strategies IGES | Matsuoka S.,Hiroshima University
Environmental Economics and Policy Studies | Year: 2014

In developing countries contingent valuation (CV) has become an important tool for estimating willingness to pay (WTP). So far, however, the CV studies usually have not assessed the validity of the WTP estimates mainly due to ambiguities in the criteria for scope sensitivity analysis. In this article we clarify the criteria from theoretical and empirical aspects. The main debate on scope sensitivity analysis targets the proportionality theory: One group supports strong proportionality, and the other group supports weak proportionality. We highlight the shortcomings of strong proportionality and support weak proportionality. We set up the criteria for statistical significance and plausible responsiveness between the WTP and its explanatory variables. We conducted scope sensitivity of our case study from rural Pakistan to show its applicability in developing countries and to test the validity of our WTP estimates. Statistical analysis, based on the maintained hypothesis, reveals that the magnitude of the benefits and per capita income are significant variables that influence the WTP. The Kruskall-Wallis test reconfirmed the significance of the size of the benefits. Plausible responsiveness is evident from the influence of the household characteristics over the WTP. Finally, we concluded that CV can provide valid results in developing countries if the survey is conducted according to the mainstream guidelines. Further empirical testing is required to support the criterion of plausible responsiveness. © 2002, Springer Japan.

Noda S.,Hiroshima University | Tanabe S.,Hiroshima University | Suzuki T.,Hiroshima University
Journal of Agricultural and Food Chemistry | Year: 2012

Flavonoids, present in fruits, vegetables, and teas, provide beneficial effects for our health. We investigated the effect of a number of flavonoids on tight junction (TJ) barrier integrity in human intestinal Caco-2 cells. Transepithelial electrical resistance (TER; a TJ integrity marker) across cell monolayers was measured in cells incubated with flavonoids for 24 h. Chrysin decreased the TER, indicating a decrease in TJ integrity. Daidzein, hesperetin, naringenin, and morin increased the TER, indicating increased TJ integrity. Luteolin and genistein increased or normalized the TER after a transient decrease. Immunoblot analysis revealed that these changes in TER were caused by modification of the cytoskeletal association and expression of TJ proteins, zonula occludens (ZO)-1, ZO-2, occludin, junctional adhesion molecule-1, and/or claudins. Our results suggest that various flavonoids participate in the regulation of intestinal TJ barrier integrity and that this regulation may partially contribute to the flavonoid-mediated biological effects on our health. © 2012 American Chemical Society.

Fujita S.,Hiroshima University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

This paper studies the problem of broadcasting successive chunks to all nodes in a network under an assumption such that each node can upload a chunk to exactly one node at a time. This models the delivery of a video stream in a Peer-to-Peer (P2P) network in which chunks of a stream are successively given by the media server. We propose two schemes for solving the problem. The first scheme attains an optimum broadcast time of steps, where n is the number of nodes, using an overlay network in which each node has children. The second scheme reduces the number of children by slightly increasing the broadcast time. More concretely, it completes each broadcast in steps when the number of children is bounded by O((f(n))2) for any function satisfying f(n) = ω(1) and f(n) = o(n). © 2014 Springer International Publishing Switzerland.

Huys R.,Natural History Museum in London | Fatih F.,St George's, University of London | Ohtsuka S.,Hiroshima University | Llewellyn-Hughes J.,Natural History Museum in London
International Journal for Parasitology | Year: 2012

Poecilostome cyclopoids are among the most morphologically diverse copepods, having established symbiotic relationships with teleosts, elasmobranchs and invertebrate hosts belonging to no fewer than 14 marine phyla. Many parasitic lineages display radically divergent body plans and on that basis have traditionally been placed at higher taxonomic rank than they deserve. The most recent example is the monotypic family Umazuracolidae, established for a derived fish parasite with bomolochiform affinities. Phylogenetic analysis of complete ssrDNA (18S) sequences of 44 species belonging to 21 families of cyclopoid copepods shows that there is no support for the familial distinctiveness of the Umazuracolidae. Both maximum parsimony tree reconstruction and Bayesian inference, operating under the GTR + I + Γ model of nucleotide substitution, unambiguously placed Umazuracola elongatus in the Taeniacanthidae within the predominantly fish parasitic bomolochiform complex, refuting the original suggestion of a shared most recent common ancestry with polychaete symbionts. The phylogenies also revealed that the bomolochiform families and the Clausidiidae (and allies) form a monophyletic group, the clausidiiform complex, with high nodal support under both methods. Bayesian inference suggested a diphyletic origin of the "Poecilostomatoida" with the clausidiiform family-group holding a basal position while the traditional cyclopoid families form a monophyletic group in apposition to a second poecilostomatoid clade; however, maximum parsimony results were equivocal, depending on outgroup selection. Scrutiny of the morphological characters diagnosing the monotypic families Tegobomolochidae and Tuccidae demonstrated that they merely represent derived lineages within more inclusive taxa, the former being related to a group of nostril-inhabiting genera within the Bomolochidae, the latter forming the sistergroup of Taeniacanthodes within the Taeniacanthidae. The taeniacanthid genus Makrostrotos occupies a position at the base of the bomolochiform complex and is fixed as the type of a new family, Makrostrotidae. Although both morphological and molecular evidence hint that the Bomolochidae is nested within a paraphyletic Taeniacanthidae, the status quo of maintaining both families is favoured here pending additional molecular data. The bomolochiform complex, comprising the Bomolochidae, Taeniacanthidae, Telsidae and Makrostrotidae, is attributed superfamilial rank as the Bomolochoidea. A recent controversial phylogenetic analysis of the poecilostomatoid families is shown to be flawed, being based on a dataset containing imperfect or misleading information, and characters whose states were wrongly assessed. © 2011 Australian Society for Parasitology Inc.

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.

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.

Morita K.,Hiroshima University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2016

A three-neighbor triangular partitioned cellular automaton (TPCA) is a CA whose cell is triangular-shaped and divided into three parts. The next state of a cell is determined by the three adjacent parts of its neighbor cells. The framework of TPCA makes it easy to design reversible triangular CAs. Among them, isotropic 8-state (i.e., each part has two states) TPCAs, which are called elementary TPCAs (ETPCAs), are extremely simple, since each of their local transition functions is described by only four local rules. In this paper, we investigate a specific reversible ETPCA T0347, where 0347 is its identification number in the class of 256 ETPCAs. In spite of the simplicity of the local function and the constraint of reversibility, evolutions of configurations in T0347 have very rich varieties, and look like those in the Game-of-Life CA to some extent. In particular, a “glider” and “glider guns” exist in T0347. Furthermore, using gliders to represent signals, we can implement universal reversible logic gates in it. By this, computational universality of T0347 is derived. © IFIP International Federation for Information Processing 2016.

Kang M.J.,Hiroshima University | Doi I.,Hiroshima University | Mori H.,Hiroshima University | Miyazaki E.,Hiroshima University | And 3 more authors.
Advanced Materials | Year: 2011

A series of alkylated dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b] thiophenes (Cn-DNTTs) were developed as vapor-processable organic semiconductors for organic thin-film transistors (OTFTs). All the C n-DNTT-based OTFTs showed typical p-channel FET characteristics and among them, C10-DNTT possessing two n-decyl groups gave excellent FET characteristics under the ambient conditions with mobility close to 8.0 cm 2 V-1 s-1 and Ion/Ioff > 108. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Ide Y.,Japan International Center for Materials Nanoarchitectonics | Torii M.,Hiroshima University | Sano T.,Hiroshima University
Journal of the American Chemical Society | Year: 2013

When the partial oxidation of benzene to phenol, which is one of the most important reactions in chemical industry, was conducted using TiO2 in the presence of a phenol-philic adsorbent derived from a layered silicate, phenol was recovered in unprecedentedly high yield and purity. This resulted from the fact that the adsorbent captured the generated phenol promptly, selectively, and effectively to prevent the overoxidation, after which the captured phenol could be easily eluted. © 2013 American Chemical Society.

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.

Ide Y.,Hiroshima University | Kagawa N.,Hiroshima University | Sadakane M.,Hiroshima University | Sano T.,Hiroshima University
Chemical Communications | Year: 2012

Photocatalytic mineralization of aqueous formic acid and phenol on pure TiO 2 under sunlight irradiation was substantially accelerated to give a reliable photocatalytic efficiency by conducting the reactions in the presence of a CO 2 sorbent, amine-containing SBA-15, placed in the gas phase of the reactor. © 2012 The Royal Society of Chemistry.

Pro-oxidative effect of phenolic antioxidant (vitamin E) in combination with the initiators on human low-density lipoprotein is known. Recently I reported that oxidative stress induced by vitamin E in combination with the herbicide paraquat enhances structural chromosomal damage in cultured anuran leukocytes. In the present study, the phenolic antioxidant vitamin E-synthetic-analogue 2,6-di-tert-butyl-p-cresol (BHT) in combination with paraquat was found to enhance structural chromosomal damage in cultured Pelophylax (Rana) nigromaculatus leukocytes more than paraquat only and paraquat plus nicotinamido adenine dinucleotido phosphate served as positive control, although BHT only had no effect on induction of structural chromosomal damage. Paraquat plus BHT-enhanced structural chromosomal damage was inhibited by combination of the superoxide dismutase mimic Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin and the hydrogen peroxide scavenger catalase. In test based on reduction of paraquat cation, BHT was found to reduce paraquat cation chemically to paraquat monocation radical. These results suggest that BHT functions in chemically donating electron to paraquat and thereby induces an acute accumulation of reactive oxygen species, resulting in increase in chromosomal damage. © 2012 The Authors.

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.

Mori T.,RIKEN | Mori T.,Hiroshima University | Nishimura T.,Hiroshima University | Yamamoto T.,Hiroshima University | And 6 more authors.
Journal of the American Chemical Society | Year: 2013

We describe a new synthetic route to the [1]benzothieno[3,2-b][1] benzothiophene (BTBT) substructure featuring two consecutive thiophene-annulation reactions from o-ethynyl-thioanisole substrates and arylsulfenyl chloride reagents that can be easily derived from arylthiols. The method is particularly suitable for the synthesis of unsymmetrical derivatives, e.g., [1]benzothieno[3,2-b]naphtho[2,3-b]thiophene, [1]benzothieno[3,2-b] anthra[2,3-b]thiophene, and naphtho[3,2-b]thieno[3,2-b]anthra[2,3-b]thiophene, a selenium-containing derivative, [1]benzothieno[3,2-b][1]benzoselenophene. It also allows us to access largely π-extended derivatives with two BTBT substructures, e.g., bis[1]benzothieno[2,3-d:2′,3′-d′]benzo[1, 2-b:4,5-b′]dithiophene and bis[1]benzothieno[2,3-d:2′,3′- d′]naphtho[2,3-b:6,7-b′]dithiophene (BBTNDT). It should be emphasized that these new BTBT derivatives are otherwise difficult to be synthesized. In addition, since various substrates and reagents, o-ethynyl-thioanisoles and arylthiols, respectively, can be combined, the method can be regarded as a versatile tool for the development of thienoacene-based organic semiconductors in this class. Among the newly synthesized materials, highly π-extended BBTNDT afforded very high mobility (>5 cm2 V-1 s-1) in its vapor-deposited organic field-effect transistors (OFETs), which is among the highest for unsubstituted acene- or thienoacenes-based organic semiconductors. In fact, the structural analyses of BBTNDT both in the single crystal and thin-film state indicated that an interactive two-dimensional molecular array is realized in the solid state, which rationalize the higher carrier mobility in the BBTNDT-based OFETs. © 2013 American Chemical Society.

Yong T.L.-K.,Hiroshima University | Matsumura Y.,Hiroshima University
Industrial and Engineering Chemistry Research | Year: 2012

The effect of wood addition on supercritical water gasification (SCWG) of poultry manure is investigated for broiler-derived wastes consisting of manure and the bedding material such as wood sawdust. SCWG of poultry manure (0.5 wt %) with Eucalyptus wood (0-0.3 wt %) is conducted in a continuous flow system for the temperature range of 550-650 °C and a pressure of 25 MPa. The organic matter in the poultry manure is mainly converted into fuel gases such as H 2, CO 2, and CH 4. During SCWG of poultry manure and wood, not only decomposition of both but also reactions between their decomposition products occur. Wood biomass (cellulose and hemicellulose) are easily decomposed in SCW compared to poultry manure. However, at higher loading of wood in the mixture, the existence of inhibiting compounds in the wood decelerates the gas producing pathways in the overall reactions. The usage of activated carbon in the feedstock mixture improves the gasification efficiency. © 2012 American Chemical Society.

Methacrylic monomer was used in soap-free emulsion polymerization in order to obtain a stable dispersion containing particles of the polymerized monomer. 2,2′-Azobis(2-methylpropionitrile) (AIBN) or 1,1′-azobis(1-acetoxy- 1-phenylethane) (OTAZO-15) were used as the radical initiator. Although particles with a size of about 1.0 μm were obtained when using methyl methacrylate as the monomer and AIBN as the initiator, the particles did not exhibit good dispersion stability. When OTAZO-15, which has phenyl rings, was used as the initiator, the monomer phase solidified instead of forming particles in the aqueous phase. Benzyl methacrylate (BMA) monomer, which contains a phenyl ring, was polymerized using AIBN. Negatively charged particles with a size of 0.90 μm were formed. These particles exhibited good dispersion stability probably because of the pi electrons of the phenyl ring in the BMA monomer. The method in this study allows the synthesis of nearly micron-sized particles without surfactant, organic solvent, and electrolyte. © 2013 Springer-Verlag Berlin Heidelberg.

Nosaka M.,Hiroshima University | Okamura H.,Hiroshima University
Journal of Alternative and Complementary Medicine | Year: 2015

Objectives: The aim of this study was to assess the effect of the daily practice of a yoga therapy program learnt during a single session of an integrated yoga intervention that was developed by us as a stress management tool for school employees. Subjects: Ninety school employees. Design: Case-control study. Three months after the intervention, the subjects were assigned to a daily practice group (case: n=43) and a nonconsecutive daily practice group (control: n=47) according to their daily practice level of the yoga therapy program. Interventions: The subjects participated in a stress management education program based on an integrated yoga therapy session. The program included psychological education and counseling about stress management and yoga theories, as well as the practices of asanas, pranayama, relaxation, and cognitive structure based on Indian philosophy. Outcome measures: Assessments were performed before and after the program using the Subjective Units of Distress for mind and body and the Two-Dimensional Mood Scale. The General Health Questionnaire 28 (GHQ28) was used to assess the mental health state before the intervention and at 3 months after the program. Results: The subjects showed significant increases in their levels of calmness, comfort, and cheerfulness (p<0.001) and significant decreases in cognitive mind and body stress (p<0.001) after participating in the integrated yoga program. A comparison of the total scores on the GHQ28 using a two-way analysis of variance showed significant differences between the two groups in terms of both interaction (p=0.047) and the main effect (p=0.026). Conclusions: The present results suggested that a single session of an integrated yoga program was effective for reducing stress and that the mental health of school employees was promoted by the daily practice of the yoga therapy program. © Copyright 2015, Mary Ann Liebert, Inc. 2015.

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.

Higashi Y.,Hiroshima University | Kihara Y.,Hiroshima University | Noma K.,Hiroshima University
Hypertension Research | Year: 2012

Hypertension is one of the common diseases in the elderly. The prevalence of hypertension markedly increases with advancing age. Both aging and hypertension have a critical role in cardiovascular and cerebrovascular complications. Although aging and hypertension, either independently or collectively, impair endothelial function, aging and hypertension may have similar cascades for the pathogenesis and development of endothelial dysfunction. Nitric oxide (NO) has an important role in regulation of vascular tone. Decrease in NO bioavailability by endothelial dysfunction would lead to elevation of blood pressure. An imbalance of reduced production of NO or increased production of reactive oxygen species, mainly superoxide, may promote endothelial dysfunction. One possible mechanism by which the prevalence of hypertension is increased in relation to aging may be advancing endothelial dysfunction associated with aging through an increase in oxidative stress. In addition, endothelial cell senescence is also involved in aging-related endothelial dysfunction. In this review, we focus on recent findings and interactions between endothelial function, oxidative stress and hypertension in aging. © 2012 The Japanese Society of Hypertension All rights reserved.

Nakasa T.,Hiroshima University | Shibuya H.,Hiroshima University | Nagata Y.,Hiroshima University | Niimoto T.,Hiroshima University | Ochi M.,Hiroshima University
Arthritis and Rheumatism | Year: 2011

Objective MicroRNA, a class of noncoding RNA, play a role in human diseases. MicroRNA-146a (miR-146a) is a negative regulator of immune and inflammatory responses, and is strongly expressed in rheumatoid arthritis (RA) synovium and peripheral blood mononuclear cells (PBMCs). This study was undertaken to examine whether miR-146a expression inhibits osteoclastogenesis, and whether administration of miR-146a prevents joint destruction in mice with collagen-induced arthritis (CIA). Methods PBMCs from healthy volunteers were isolated and seeded in culture plates. The following day, double-stranded miR-146a was transfected and cultured in the presence of macrophage colony-stimulating factor and either tumor necrosis factor α or RANKL. After 3 weeks, tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells were counted. Three days after miR-146a culture, the expression of c-Jun, nuclear factor of activated T cells c1 (NF-ATc1), PU.1, and TRAP was evaluated by quantitative reverse transcriptase-polymerase chain reaction. After the onset of distinct arthritis in mice with CIA, double-stranded miR-146a or nonspecific double-stranded RNA was administered twice by intravenous injection. Radiographic and histologic examinations were performed at 4 weeks. Results The number of TRAP-positive multinucleated cells in human PBMCs was significantly reduced by miR-146a in a dose-dependent manner. The expression of c-Jun, NF-ATc1, PU.1, and TRAP in PBMCs was significantly down-regulated by miR-146a. Administration of miR-146a prevented joint destruction in mice with CIA, although it did not completely ameliorate inflammation. Conclusion Our findings indicate that expression of miR-146a inhibits osteoclastogenesis and that administration of double-stranded miR-146a prevents joint destruction in arthritic mice. Administration of miR-146a has potential as a novel therapeutic target for bone destruction in RA. Copyright © 2011 by the American College of Rheumatology.

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.

Suzuki T.,Hiroshima University
Cellular and Molecular Life Sciences | Year: 2013

The gastrointestinal epithelium forms the boundary between the body and external environment. It effectively provides a selective permeable barrier that limits the permeation of luminal noxious molecules, such as pathogens, toxins, and antigens, while allowing the appropriate absorption of nutrients and water. This selective permeable barrier is achieved by intercellular tight junction (TJ) structures, which regulate paracellular permeability. Disruption of the intestinal TJ barrier, followed by permeation of luminal noxious molecules, induces a perturbation of the mucosal immune system and inflammation, and can act as a trigger for the development of intestinal and systemic diseases. In this context, much effort has been taken to understand the roles of extracellular factors, including cytokines, pathogens, and food factors, for the regulation of the intestinal TJ barrier. Here, I discuss the regulation of the intestinal TJ barrier together with its implications for the pathogenesis of diseases. © 2012 Springer Basel AG.

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.

Asaoka S.,Hiroshima University | Takahashi Y.,Hiroshima University | Araki Y.,Hiroshima University | Tanimizu M.,Japan Agency for Marine - Earth Science and Technology
Chemical Geology | Year: 2013

This study has demonstrated the similarities in the geochemical behavior of Sb and As under relatively oxic condition within a river system of Kamo-Ichinokawa in Japan. Speciation data in both water and solid phases were obtained by HPLC-ICP-MS and X-ray absorption fine structure analyses, respectively. The solid-water distributions of Sb and As are similar at all sampling points. Scavenging of the two elements from the aqueous phase was attributed to their adsorption onto iron (hydr)oxides. The two elements were finally incorporated into the river sediments where the host phases of Sb and As were determined by XAFS and sequential extraction experiments. The contribution of Sb and As adsorption onto particulate matters in the river water was relatively small, suggesting that the two elements are conservative under river water oxic conditions (Eh > 200. mV). The distribution coefficients of Sb and As for river water and river sediments were within a factor of 4.7 under oxic conditions. In our model calculations, however, their distribution coefficients largely differed by more than a factor of 25 to 50 under reducing conditions (Eh < 90. mV). This could be extended to infer the origin of As in natural systems under oxic conditions based on the As/Sb ratio where Sb and As behave similarly. © 2012 Elsevier B.V.

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).

Kawano S.,Hiroshima University | Yoshino T.,Okayama University | Katayama I.,Hiroshima University
Geophysical Research Letters | Year: 2012

[1] Electrical conductivity of serpentinite with various amounts of magnetite was measured during shear deformation at high pressure and temperatures (P = 1.0 GPa, T = 750 K) corresponding to mantle wedge conditions to evaluate the contribution of aligned magnetite to the bulk conductivity of serpentinite. Under hydrostatic conditions, the sample conductivity considerably increases when the magnetite volume fraction exceeds 25% in volume, suggesting the presence of the percolation threshold for magnetite interconnection. During shear deformation, the conductivity for the samples with less than 25 vol.% magnetite increased by an order of magnitude or higher with increasing shear strain up to 9, which is likely a result of the clustering or realignment of magnetite grains in the serpentinites. However, activation enthalpy was nearly constant before and after deformation experiments, suggesting that shear deformation is unlikely to enhance establishment of interconnection of magnetite. Consequently, more than 25 vol.% magnetite is needed to establish connectivity of magnetite in serpentinite. On the other hand, the conductivity of serpentinite with low volume fraction of magnetite (5%), which is typical concentration of natural serpentinites, is almost similar to that of magnetite-free serpentinites. The present results show that the interconnection of magnetite in serpentinites by shear deformation is not expected as an origin of the high conductivity anomaly occasionally observed at the slab interface in the mantle wedge. The origin of high conductivity, therefore, indicates the presence of aqueous fluid with high salinity rather than the magnetite interconnection. © 2012. American Geophysical Union. All Rights Reserved.

Yokoyama Y.,Hiroshima University | Tanaka K.,Hiroshima University | Takahashi Y.,Hiroshima University
Geochimica et Cosmochimica Acta | Year: 2012

The sorption and coprecipitation experiments of arsenic (As) with calcite coupled with determinations of the chemical state of As both in the reaction fluid and in calcite were conducted to investigate the influence of the As oxidation state on its immobilization into calcite. The oxidation states of As in calcite and water were determined via As K-edge XANES and HPLC-ICP-MS analysis, respectively. The results of the sorption experiments at pH 8.2 show that only As(V) is distributed to calcite regardless of the As oxidation state in the solution. In coprecipitation experiments, As(V) is preferentially incorporated into calcite over a wide range of pH (7-12). On the other hand, the incorporation of As(III) into calcite is not observed at circumneutral pH. This difference between As(III) and As(V) is attributed to the fact that their dissolved species are neutral vs. negatively charged, respectively, at circumneutral pH (arsenite as H 3AsO 3; arsenate as H 2AsO 4 - or HAsO 4 2-). As the pH increases (>9), up to 33% of As(III)/As total ratio is partitioned into calcite or a precursor of calcite (metastable vaterite formed during the early stage of precipitation). The higher interaction of As with calcite at an alkaline pH compared with circumneutral pH is due to the negative charge of As(III) at alkaline pH. However, the As(III)/As total ratio decreases as time progresses and only As(V) can be found finally in calcite. The ratio of distribution coefficients of As(III) and As(V) into calcite (K As(V)/K As(III)) at pH ∼7 is larger than 2.1×10 3, suggesting that the oxidation state of As is a significant issue in considering the interaction between As and calcite in groundwater. Moreover, low K As(III) shows that the sequestration of As via coprecipitation with calcite is not an important chemical process under reducing conditions, such as in the groundwaters in Bangladesh and other As-contaminated areas where As(III) is the dominant dissolved species of As.In the system spiked only with As(III), the XANES analysis detected As(V) in calcite, where the partitioning of As into calcite is very limited as stated above. Therefore, HPLC-ICP-MS and cyclic voltammetric measurements were performed to clarify the As(V)-incorporation mechanism in the As(III) system. As a result, the oxidation of As(III) to As(V) and the stabilization of As(V) in a solution in the presence of the Ca 2+ ion are observed. These phenomena result from the formation of calcium arsenate complexes in the aqueous phase. This complexation is an important process for the coprecipitation of As with calcite. Hence, As is incorporated into calcite as As(V) even from the As(III) solution at circumneutral pH, wherein As(III) exists as neutral arsenite with little interaction with calcite. © 2012 Elsevier Ltd.

Lee H.S.,Hiroshima University | Yamashita T.,Hiroshima University | Mishima T.,Hiroshima Institute of Technology
Progress in Oceanography | Year: 2012

In this paper, the multi-decadal variations of the Multivariate ENSO Index (MEI) and the Pacific Decadal Oscillation (PDO) index were studied to determine their influence on tropical cyclones (TCs) using the empirical mode decomposition (EMD) method and Hilbert spectral analysis. The ENSO and PDO are closely associated with various oceanic and atmospheric factors that govern TC activities in the western North Pacific (WNP). From the analysis results, multi-decadal oscillations with characteristic periods of 13 and 32.5. years from MEI, and about 16.7 and 32.8. years from PDO, were obtained. These values showed good agreement with the values obtained in other studies. The results of category 4-5 TCs and category 5 TCs also showed possible multi-decadal oscillations of about 15- and 37-year timescales, indicating that low frequency multi-decadal oscillations of intense TC occurrence in the WNP is influenced by the multi-decadal oscillations of ENSO and PDO. When seeking adaptation and mitigation measures for future climate scenarios, the multi-decadal variations of climate and their impacts on extreme events such as TCs should be taken into account together with the background of the global warming trend. © 2012 Elsevier Ltd.

Katayama I.,Hiroshima University | Terada T.,Hiroshima University | Okazaki K.,Hiroshima University | Tanikawa W.,Japan Agency for Marine - Earth Science and Technology
Nature Geoscience | Year: 2012

Slow earthquakes occur at the plate interface in subduction zones. These low-frequency tremors and slow-slip events are often located at about 30a €‰km depth, near the boundary between the crust and mantle (Moho) on the overriding plate. Slow earthquakes occur on fault patches with extremely low frictional strength. This weakness is generally assumed to result from increased pore-fluid pressures and may be linked to the release of fluids from the descending plate. Here we propose that a contrast in permeability across the Moho results in the accumulation of water and the build-up of pore-fluid pressure at the corner of the mantle wedge that overlies the subducting plate. We use laboratory measurements of permeability to show that gabbroic rock layers in the crust are two orders of magnitude less permeable than serpentinite layers in the underlying hydrated mantle rocks. Inserting our experimental data into a numerical model that simulates pore pressure evolution across the Moho, we show that the pore-fluid pressure at this boundary can be as high as lithostatic pressure. We suggest that water released from the descending plate is trapped at the corner of the mantle wedge owing to this permeability barrier, and then causes the localized slow earthquakes that are triggered by fault instabilities.

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.

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.

Tokunaga M.,Hiroshima University
Asian journal of endoscopic surgery | Year: 2014

Under mirror-image conditions, surgeons often become confused and their task performance may deteriorate. This study aimed to quantitatively investigate the difficulty of performing laparoscopic surgery based on a mirror image and to find methods to improve performance under these conditions. Twelve medical students with no prior endoscopic surgical experience and 10 surgical residents, each with over 50 laparoscopic surgery experiences, participated in this study. Three measures were assessed using the Hiroshima University Endoscopic Surgical Assessment Device: the deviation with integrated time, the approaching time, and the peak velocity. The scope was placed at 0° (coaxial position), 180° (mirror-image condition), and 180° using the Broadview camera system. Each participant performed the Hiroshima University Endoscopic Surgical Assessment Device task 10 times. The deviation with integrated time, the approaching time, and the peak velocity were better for surgical residents than for novices at 0° (P < 0.001, P = 0.001, P = 0.011). The deviation with integrated time, the approaching time, and the peak velocity at 180° were significantly worse than the corresponding values at 0° (P < 0.0001) for both surgical residents and novices. All three types of Hiroshima University Endoscopic Surgical Assessment Device assessment at 180° were significantly better when the Broadview camera system was used than when it was not (P < 0.0001). This study showed quantitatively the difficulty in manipulating laparoscopic instruments in mirror-image conditions. Using the Broadview camera system improved surgeons' performance under mirror-image conditions during laparoscopic surgery. © 2013 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd.

Yamanaka S.,Hiroshima University
Dalton Transactions | Year: 2010

Compounds with cage-like structures of elemental silicon and carbon are comparatively reviewed. Barium containing silicon clathrate compounds isomorphous with type I gas hydrates were prepared using high pressure and high temperature (HPHT) conditions, and found to become superconductors. The application of HPHT conditions to Zintl binary silicides have produced a number of silicon-rich cage-like structures including new clathrate structures; most of them are superconductors. Carbon analogs of silicon clathrates can be prepared by 3D polymerization of C60 under HPHT conditions, which are new allotropes of carbon with expanded framework structures. The crystal chemistry and characteristic properties of some related compounds are also reviewed. © 2010 The Royal Society of Chemistry.

Kajitani K.,Hiroshima University | Tanaka Y.,Hiroshima University | Arihiro K.,Hiroshima University | Kataoka T.,Hiroshima University | Ohdan H.,Hiroshima University
Breast Cancer Research and Treatment | Year: 2012

We investigated the role of human natural killer (NK) cells in the peripheral blood (PB) and liver in controlling breast cancer. The proportion of NK cells among liver mononuclear cells was significantly higher than among PB mononuclear cells. Liver NK cells inductively expressed higher levels of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) than PB NK cells in response to interleukin-2 (IL-2). Liver NK cells displayed higher cytotoxicity against various breast cancer cell lines (MDA-MB231, MDA-MB453, MDA-MB468, and MCF-7) after IL-2 stimulation than did PB NK cells. Anti-HER2 monoclonal antibody (mAb) promoted the cytotoxicity of both the types of NK cells toward HER2-expressing cell lines. All breast cancer cell lines highly expressed death-inducing TRAIL receptors, death receptor 4, but did not express death-inhibitory receptors (DcR1 and DcR2). Both PB and liver NK cell-induced cytotoxicity was inhibited partially by anti-TRAIL mAb and more profoundly by the combination of anti-TRAIL mAb and concanamycin A, indicating that TRAIL and perforin are involved. IL-2-stimulated liver and PB NK cells exhibited upregulated expression of CXCR3, which bind to the chemokines CXCL9, CXCL10, and CXCL11 secreted by breast cancer cells. We also found that IFN-γ promoted the production of CXCL10 from breast cancer cells. The results of this study show that IFN-γ secreted from NK cells likely promotes the production of CXCL10 from breast cancer cells, which in turn accelerates the migration of CXCR3-expressing NK cells into the tumor site. These findings suggest the possibility of a therapeutic approach by either activation of endogenous PB and liver NK cells or adoptive transfer of in vitro-activated autologous NK cells. © 2012 Springer Science+Business Media, LLC.

Koga N.,Hiroshima University | Nishikawa K.,Hiroshima University
Crystal Growth and Design | Year: 2014

A specimen sample of coral skeleton (Pavona, Okinawa, Japan) was selected to study the mechanistic relationship between aragonite-calcite transformation and the thermal dehydration of the included water in biogenic aragonite. The sample exhibited three mass loss steps attributed to the thermal dehydration of the included water (2.8% of the sample mass) before the thermal decomposition of CaCO3. The aragonite-calcite transformation simultaneously occurred during the second dehydration step of the included water in a temperature region lower by approximately 100 K than in synthetic and geological aragonites. During the thermal dehydration of the included water and the aragonite-calcite transformation, the root structure of polygonal plate stacking in the biogenic aragonite wa