Chiba, Japan
Chiba, Japan

Chiba University and it is also abbreviated as Chibadai is a national university in the city of Chiba, Japan. It offers Doctoral degrees in education as part of a coalition with Tokyo Gakugei University, Saitama University, and Yokohama National University. The university was formed in 1949 from existing educational institutions in Chiba Prefecture, and absorbed over a period of years Chiba Medical University , a preparatory department of the Tokyo Medical and Dental University, Chiba Normal School , Tokyo Polytechnic High School , Chiba Horticultural High School, and others. Chiba University was reincorporated in 2010 under the National University Corporation Act. Chiba University has been ranked 75th on the Asia University Rankings 2013 Top 100 by "The Times Higher Education".Currently, Chiba University consists of nine faculties, the university library, the university hospital and other educational and research facilities. With 11,179 students in the undergraduate program, it has long been one of the largest universities in Japan. As for the graduate school, there are about 2,354 students in ten master's programs and 1,220 in nine doctoral programs.Chiba University is proud of its productive faculties and varied courses, the particulars of which will be introduced in the following sections. The University's four campuses, Nishi-Chiba, Inohana, Matsudo, and Kashiwanoha are ideally located in Chiba Prefecture, an area noted for its industrial, intellectual and international achievements. In recent decades Chiba has undergone rapid development which in many ways rivals the neighboring Tokyo Metropolis. Many national projects have been based in Chiba Prefecture, and now Chiba has one of the main international transport centers and one of the largest business centers in Japan . Many new academic and industrial complexes for the advanced science are located in Chiba Prefecture. The developments in Chiba today are representative of tomorrow's Japan. Matters occurring in the most progressive parts of Japan, or even in the world, will provide rich materials for research in various aspects of the human, social, industrial and natural science.Chiba University has achieved a high degree of participation in international cooperative research projects. Chiba University presently has a large body of international research scholars and students studying on its various campuses. As of 2009, there are approximately 477 international researcher and 957 international students. Starting October, 1996, Chiba University launched a one-year scholarship program designed to provide international students with the opportunity to take courses in English. Wikipedia.

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An object of the present invention is to provide a film which has high visibility in solid state and a product which has the film, with simple material composition. One aspect of the present invention is a film which comprises a core-shell particle which has a core and a shell which covers the core. Moreover, another aspect of the present invention is a product which is covered with the film. Further, another aspect of the present invention is a solution in which core-shell particles are dispersed. Hereby, the present invention is possible to realize a film which has high visibility in solid state and a product which has the film, with simple material composition.

A method for quantitatively evaluating chromatin structural changes using pixel imaging of the nucleus is provided. Pixel imaging of the nucleus can include capturing one or more images of a nucleus of one or more nucleic acid stain treated cells. The stain intensity can be measured by quantitating the intensity. The mean and/or standard deviation of stain intensity per pixel can be used to determine chromatin condensation levels or chromatin structural change.

Olympus Corporation and Chiba University | Date: 2016-10-28

Provided is an image processing apparatus including a transformation unit that is configured to deform images so that corresponding points in a plurality of images obtained from several viewpoints with respect to the same subject are matched; a separating unit that is configured to separate specular-reflection components from the plurality of images transformed by the transformation unit and create an image from which the specular-reflection component is removed; and an image reconstructing unit that is configured to combine at least one of the specular-reflection components of the plurality of images, separated by the separating unit, and the image from which the specular-reflection component is removed.

Advanced Healthcare Co. and Chiba University | Date: 2017-01-25

This invention provides a simple projector system that can be operated by a user who is not an expert of image processing technology. The projector system comprises a projector (1), a personal computer (2), a mouse (3), and a calibration board (4). A checker flag pattern is added to the calibration board (4), and an intersection point serves as a marker. A cursor, which is projected from the projector (1) onto the calibration board (4), is used as an intuitive input interface. An operator, while seeing the cursor, operates the mouse (3), thereby placing the cursor onto the calibration marker. In this state, the operator clicks the mouse (3), thereby selecting the calibration marker. The operator then acquires the corresponding projection image coordinates on the basis of the selection instruction.

The thermal phase behavior of 1-butyl-3-methylimidazolium hexafluorophosphate, which forms three polymorphic crystals (α, β, and γ), has been re-investigated by the simultaneous measurements of Raman spectroscopy and calorimetry. The peak assigned to the phase change from β to γ phase is found to be exothermic and, in striking contrast with a previous report, the peak for this transition is observed near 255 K by recooling and subsequent reheating of the β phase. This finding enabled separate measurements of the melting points (285.8 and 285.3 K), fusion enthalpies (13.1 and 22.6 kJ mol-1), and entropies of the β and γ phases, respectively. © 2013 Elsevier Ltd. All rights reserved.

Sekiguchi T.,Suntory Institute for Bioorganic Research | Ogasawara M.,Chiba University | Satake H.,Suntory Institute for Bioorganic Research
Journal of Endocrinology | Year: 2012

Cholecystokinin (CCK) and gastrin are vertebrate brain-gut peptides featured by a sulfated tyrosine residue and a C-terminally amidated tetrapeptide consensus sequence. Cionin, identified in the ascidian, Ciona intestinalis, the closest species to vertebrates, harbors two sulfated tyrosines and the CCK/gastrin consensus tetrapeptide sequence. While a putative cionin receptor, cior, was cloned, the ligand-receptor relationship between cionin and CioR remains unidentified. Here, we identify two cionin receptors, CioR1 and CioR2, which are the aforementioned putative cionin receptor and its novel paralog respectively. Phylogenetic analysis revealed that CioRs are homologous to vertebrate CCK receptors (CCKRs) and diverged from a common ancestor in the Ciona-specific lineage. Cionin activates intracellular calcium mobilization in cultured cells expressing CioR1 or CioR2. Monosulfated and nonsulfated cionin exhibited less potent or no activity, indicating that CioRs possess pharmacological features similar to the vertebrate CCK-specific receptor CCK1R, rather than its subtype CCK2R, given that a sulfated tyrosine in CCK is required for binding to CCK1R, but not to CCK2R. Collectively, the present data reveal that CioRs share a common ancestor with vertebrate CCKRs and indicate that CCK and CCK1R form the ancestral ligand-receptor pair in the vertebrate CCK/gastrin system. Cionin is expressed in the neural complex, digestive organs, oral siphon and atrial siphons, whereas the expression of ciors was detected mainly in these tissues and the ovary. Furthermore, cioninergic neurons innervate both of the siphons. These results suggest that cionin is involved in the regulation of siphonal functions. © 2012 Society for Endocrinology.

Letu H.,Tokai University | Hara M.,VisionTech Inc. | Tana G.,Chiba University | Nishio F.,Chiba University
IEEE Transactions on Geoscience and Remote Sensing | Year: 2012

Several studies have clarified that electric power consumption can be estimated from the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) stable light imagery. As digital numbers (DNs) of stable light images are often saturated in the center of city areas, we developed a saturated light correction method for the DMSP/OLS stable light image using the nighttime radiance calibration image of the DMSP/OLS. The comparison between the nonsaturated part of the stable light image for 1999 and the radiance calibration image for 1996-1997 in major areas of Japan showed a strong linear correlation (R 2 = 92.73) between the DNs of both images. Saturated DNs of the stable light image could therefore be corrected based on the correlation equation between the two images. To evaluate the new saturated light correction method, a regression analysis is performed between statistic data of electric power consumption from lighting and the cumulative DNs of the stable light image before and after correcting for the saturation effects by the new method, in comparison to the conventional method, which is, the cubic regression equation method. The results show a stronger improvement in the determination coefficient with the new saturated light correction method (R 2 = 0.91, P = 1.7 · 10 -6 < 0.05) than with the conventional method (R 2 = 0.81, P = 2.6 · 10 -6 < 0.05) from the initial correlation with the uncorrected data (R 2 = 0.70, P = 4.5 · 10 -6 < 0.05). The new method proves therefore to be very efficient for saturated light correction. © 2006 IEEE.

Mori T.,RIKEN | Mori T.,Waseda University | Igawa T.,Chiba University | Tamiya G.,Yamagata University | And 3 more authors.
Current Biology | Year: 2014

Fertilization requires recognition, attachment, and membrane fusion between gametes. In metazoans, rapidly evolving surface proteins contribute to gamete recognition and adhesion [1]. Flowering plants evolved a double fertilization process wherein two immotile sperm cells are delivered to female gametes by the pollen tube, guided by elaborate communications between male and female reproductive organs [2-7]. Once released, the sperm cells contact female gametes directly prior to gamete fusion. It remains unclear whether active gamete recognition and attachment mechanisms are required for double fertilization. Here, we provide functional characterization of Arabidopsis GAMETE EXPRESSED 2 (GEX2), which encodes a sperm-expressed protein of unknown function [8]. GEX2 is localized to the sperm membrane and contains extracellular immunoglobulin-like domains, similar to gamete interaction factors in algae and mammals [9, 10]. Using a new in vivo assay, we demonstrate that GEX2 is required for gamete attachment, in the absence of which double fertilization is compromised. Ka/Ks analyses indicate relatively rapid evolution of GEX2, like other proteins involved in male and female interactions [1, 3]. We conclude that surface proteins involved in gamete attachment and recognition exist in plants with immotile gametes, similar to algae and metazoans [11, 12]. This conservation broadens the repertoire of research for plant reproduction factors to mechanisms demonstrated in animals. © 2014 Elsevier Ltd.

Kondo K.-I.,Chiba University | Shibata A.,High Energy Accelerator Research Organization
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

In the SU(2) Yang-Mills theory on the four-dimensional Euclidean lattice, we confirm the gauge-independent "Abelian" dominance (or the restricted field dominance) and gauge-independent magnetic-monopole dominance in the string tension of the linear potential extracted from the Wilson loop in the fundamental representation. The dual Meissner effect is observed by demonstrating the squeezing of the chromoelectric field flux connecting a pair of a quark and an antiquark. In addition, the circular magnetic-monopole current is induced around the chromoelectric flux. The type of the dual superconductivity is also determined by fitting the result with the dual Ginzburg-Landau model. Thus, the dual superconductor picture for quark confinement is supported in a gauge-independent manner. These results are obtained based on a reformulation of the lattice Yang-Mills theory based on the change of variables à la Cho-Duan-Ge-Faddeev-Niemi combined with a non-Abelian Stokes theorem for the Wilson loop operator. We give a new procedure (called the reduction) for obtaining the color direction field that plays the central role in this reformulation. © 2015 American Physical Society.

Sawayama M.,Nippon Telegraph and Telephone | Kimura E.,Chiba University
Vision Research | Year: 2015

When distinguishing illumination from reflectance edges, both edge blurriness and textural continuity across an edge are generally used as cues to promote the illumination-edge interpretation. However, when these cues were combined, i.e., when a dark spot having a blurred edge was placed on textured backgrounds, we unexpectedly found that the spot appears stained or painted rather than differently illuminated ("stain on texture" phenomenon). This phenomenon suggests a disruptive interaction between the visual processing of blurred edges and background texture. Our experiments showed that middle spatial-frequency components of background texture play a critical role in producing this interaction. Specifically, when a textured background had relatively stronger energy in middle spatial-frequency bands, the dark spot having a blurred edge on the textured background was perceived as differing in reflectance. The findings are discussed in view of multiple levels of visual processes: one mainly concerns low-level features such as spatial-frequency components and another is a higher-level process that takes into account the likelihood of spatial configurations in natural scenes, such as "spot shadow" in which the shadow is isolated and the shadow caster is out of sight. © 2014 The Authors.

Saito H.,Nippon Telegraph and Telephone | Shimogawa S.,Nippon Telegraph and Telephone | Tanaka S.,Chiba University | Shioda S.,Chiba University
IEEE Transactions on Mobile Computing | Year: 2012

We propose a method for estimating parameters of multiple target objects by using networked binary sensors whose locations are unknown. These target objects may have different parameters, such as size and perimeter length. Each sensors, which is incapable of monitoring the target object's parameters, sends only binary data describing whether or not it detects target objects coming into, moving around, or leaving the sensing area at every moment. We previously developed a parameter estimation method for a single target object. However, a straight-forward extension of this method is not applicable for estimating multiple heterogeneous target objects. This is because a networked binary sensor at an unknown location cannot provide information that distinguishes individual target objects, but it can provide information on the total perimeter length and size of multiple target objects. Therefore, we propose composite sensor nodes with multiple sensors in a predetermined layout for obtaining additional information for estimating the parameter of each target object. As an example of a composite sensor node, we consider a two-sensor composite sensor node, which consists of two sensors, one at each of the two end points of a line segment of known length. For the two-sensor composite sensor node, measures are derived such as the two sensors detecting target objects. These derived measures are the basis for identifying the shape of each target object among a given set of categories (for example, disks and rectangles) and estimating parameters such as the radius and lengths of two sides of each target object. Numerical examples demonstrate that networked composite sensor nodes consisting of two binary sensors enable us to estimate the parameters of target objects. © 2006 IEEE.

Takotsubo cardiomyopathy (TTC) is characterized by transient left ventricular apical ballooning with the absence of coronary occlusion, which typically occurs in older women after emotional or physical stress. The pathophysiology of TTC is not well established, though several possible causes such as catecholamine cardiotoxicity, metabolic disturbance, coronary microvascular impairment and multivessel epicardial coronary artery spasm have been proposed. A number of diagnostic criteria have been suggested in the world and not unified as single, but the most common accepted one is Mayo Clinic proposed criteria. Since the clinical presentation of TTC is usually similar to acute coronary syndrome, differential diagnosis is essential to exclude other diseases and also for its treatment. Imaging modality including echocardiogram, angio CT and cardiac MRI, and lab tests for catecholamine, troponin T, creatine kinase MB and B-type natriuretic peptide can be useful to differentiate TTC from other diseases. Prognosis is generally favorable and in-hospital mortality is from 0% to within 10%. © 2016 Elsevier Ireland Ltd. All rights reserved.

Shibata A.,High Energy Accelerator Research Organization | Kondo K.-I.,Chiba University | Shinohara T.,Chiba University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We have proposed the non-Abelian dual superconductivity picture for quark confinement in the SU(3) Yang-Mills (YM) theory, and have given numerical evidences for the restricted-field dominance and the non-Abelian magnetic monopole dominance in the string tension by applying a new formulation of the YM theory on a lattice. To establish the non-Abelian dual superconductivity picture for quark confinement, we have observed the non-Abelian dual Meissner effect in the SU(3) Yang-Mills theory by measuring the chromoelectric flux created by the quark-antiquark source, and the non-Abelian magnetic monopole currents induced around the flux. We conclude that the dual superconductivity of the SU(3) Yang-Mills theory is strictly the type I and that this type of dual superconductivity is reproduced by the restricted field and the non-Abelian magnetic monopole part, in sharp contrast to the SU(2) case: the border of type I and type II. © 2013 American Physical Society.

Liu J.Y.,National Central University | Chen Y.I.,National Central University | Chen C.H.,Kyoto University | Hattori K.,Chiba University
Journal of Geophysical Research: Space Physics | Year: 2010

We report seismo-ionospheric precursors of anomalous decreases in the total electron content (TEC) appearing day 5 prior to an M9.3 earthquake, the largest one in the last five decades, which occurred in Sumatra-Andaman, Indonesia on 26 December 2004. Sequences of global ionosphere maps of the TEC derived from worldwide ground-based receivers of the global positioning system (GPS) are used to statistically study the temporal and spatial precursors of the earthquake. It was found that the temporal precursor of the GPS TEC around the epicenter was significantly reduced during the afternoon period on d 5 before the earthquake. The spatial precursors prominently, persistently, and simultaneously appear around the epicenter and its conjugate areas of the Sumatra-Andaman earthquake. Copyright 2010 by the American Geophysical Union.

Zhong J.-Q.,National University of Singapore | Qin X.,Anhui University of Science and Technology | Zhang J.-L.,National University of Singapore | Kera S.,Chiba University | And 4 more authors.
ACS Nano | Year: 2014

Understanding the effect of intermolecular and molecule-substrate interactions on molecular electronic states is key to revealing the energy level alignment mechanism at organic-organic heterojunctions or organic-inorganic interfaces. In this paper, we investigate the energy level alignment mechanism in weakly interacting donor-acceptor binary molecular superstructures, comprising copper hexadecafluorophthalocyanine (F16CuPc) intermixed with copper phthalocyanine (CuPc), or manganese phthalocynine (MnPc) on graphite. The molecular electronic structures have been systematically studied by in situ ultraviolet photoelectron spectroscopy (UPS) and low-temperature scanning tunneling microscopy/spectroscopy (LT-STM/STS) experiments and corroborated by density functional theory (DFT) calculations. As demonstrated by the UPS and LT-STM/STS measurements, the observed unusual energy level realignment (i.e., a large downward shift in donor HOMO level and a corresponding small upward shift in acceptor HOMO level) in the CuPc-F 16CuPc binary superstructures originates from the balance between intermolecular and molecule-substrate interactions. The enhanced intermolecular interactions through the hydrogen bonding between neighboring CuPc and F 16CuPc can stabilize the binary superstructures and modify the local molecular electronic states. The obvious molecular energy level shift was explained by gap-state-mediated interfacial charge transfer. © 2014 American Chemical Society.

Ueda T.,Stanford University | Ueda T.,St Lukes International Hospital | Takaoka H.,Chiba University | Petrovitch I.,Northern Virginia Radiology Consultants | Rubin G.D.,Duke University
Radiology | Year: 2014

Purpose: To determine the prevalence of demonstrable stent-graft degradation by using three-dimensional computed tomographic (CT) angiography to assess endoleak and stent-graft migration after endovascular aortic aneurysm repair (EVAR). Materials and Methods: The institutional review board approved this retrospective study. Sixty-two consecutive patients with abdominal aortic aneurysm treated with the AneuRx stent-graft (Medtronic, Santa Rosa, Calif) were assessed between 0.5 and 9.5 years after EVAR (median, 5.1 years) for the presence of broken attachment sutures and metal-ring fractures by using CT angiography. The relative risk (RR) of delayed endoleak formation and endograft migration was calculated relative to the presence of suture breaks and metal-ring fractures. A two-tailed Fisher exact test was used to assess significant differences. Results: Suture breaks were observed in 55 of 62 subjects (89%), including 37 minor breaks (60%) and 18 major breaks (29%). Metal-ring fractures were observed in 11 of 62 subjects (18%). Twenty-seven endoleaks were observed in 24 of 62 subjects (39%) and were categorized as type I in seven of 27 (11%), type II in 16 of 27 (26%), and type III in four of 27 (6%). Major suture breaks were associated with six of seven (86%) delayed type I endoleaks (RR = 19.4, P = .003), and metal-ring fractures were associated with four of seven (57%) delayed type I endoleaks (RR = 6.2, P = .015) and three of four (75%) type III endoleaks (RR = 13.9, P = 003). Migration was observed in 15 of 62 patients (24%) and was associated with major suture breaks in 10 of 15 patients (67%, RR = 4.5, P = .001) and with metal-ring fractures in five of 11 patients (45%, RR = 4.1, P = .003). Repeat interventions were performed in 15 patients. Conclusion: Major suture breaks and metal-ring fractures are demonstrated with CT and are associated with delayed type I and III endoleaks and with stent-graft migration after EVAR. © RSNA, 2014.

Inderbitzin P.,University of California at Davis | Bostock R.M.,University of California at Davis | Davis R.M.,University of California at Davis | Usami T.,Chiba University | And 2 more authors.
PLoS ONE | Year: 2011

Knowledge of pathogen biology and genetic diversity is a cornerstone of effective disease management, and accurate identification of the pathogen is a foundation of pathogen biology. Species names provide an ideal framework for storage and retrieval of relevant information, a system that is contingent on a clear understanding of species boundaries and consistent species identification. Verticillium, a genus of ascomycete fungi, contains important plant pathogens whose species boundaries have been ill defined. Using phylogenetic analyses, morphological investigations and comparisons to herbarium material and the literature, we established a taxonomic framework for Verticillium comprising ten species, five of which are new to science. We used a collection of 74 isolates representing much of the diversity of Verticillium, and phylogenetic analyses based on the ribosomal internal transcribed spacer region (ITS), partial sequences of the protein coding genes actin (ACT), elongation factor 1-alpha (EF), glyceraldehyde-3-phosphate dehydrogenase (GPD) and tryptophan synthase (TS). Combined analyses of the ACT, EF, GPD and TS datasets recognized two major groups within Verticillium, Clade Flavexudans and Clade Flavnonexudans, reflecting the respective production and absence of yellow hyphal pigments. Clade Flavexudans comprised V. albo-atrum and V. tricorpus as well as the new species V. zaregamsianum, V. isaacii and V. klebahnii, of which the latter two were morphologically indistinguishable from V. tricorpus but may differ in pathogenicity. Clade Flavnonexudans comprised V. nubilum, V. dahliae and V. longisporum, as well as the two new species V. alfalfae and V. nonalfalfae, which resembled the distantly related V. albo-atrum in morphology. Apart from the diploid hybrid V. longisporum, each of the ten species corresponded to a single clade in the phylogenetic tree comprising just one ex-type strain, thereby establishing a direct link to a name tied to a herbarium specimen. A morphology-based key is provided for identification to species or species groups. © 2011 Inderbitzin et al.

Kuwabara S.,Chiba University | Yuki N.,National University of Singapore
The Lancet Neurology | Year: 2013

Acute motor axonal neuropathy (AMAN) is a pure motor axonal subtype of Guillain-Barré syndrome (GBS) that was identified in the late 1990s. In Asia and Central and South America, it is the major subtype of GBS, seen in 30-65% of patients. AMAN progresses more rapidly and has an earlier peak than demyelinating GBS; tendon reflexes are relatively preserved or even exaggerated, and autonomic dysfunction is rare. One of the main causes is molecular mimicry of human gangliosides by Campylobacter jejuni lipo-oligosaccharides. In addition to axonal degeneration, electrophysiology shows rapidly reversible nerve conduction blockade or slowing, presumably due to pathological changes at the nodes or paranodes. Autoantibodies that bind to GM1 or GD1a gangliosides at the nodes of Ranvier activate complement and disrupt sodium-channel clusters and axoglial junctions, which leads to nerve conduction failure and muscle weakness. Improved understanding of the disease mechanism and pathophysiology might lead to new treatment options and improve the outlook for patients with AMAN. © 2013 Elsevier Ltd.

Shahrizaila N.,University of Malaya | Kokubun N.,Dokkyo Medical University | Sawai S.,Chiba University | Umapathi T.,National Neurosciences Institute | And 4 more authors.
Neurology | Year: 2014

Objective: To comprehensively investigate the relationship between antibodies to single glycolipids and their complexes and Guillain-Barré syndrome subtypes and clinical features. Methods: In acute sera from 199 patients with Guillain-Barré syndrome, immunoglobulin G (IgG) antibodies to glycolipids and ganglioside complexes were tested using ELISA against individual antigens from single glycolipids including gangliosides (LM1, GM1, GM1b, GD1a, GalNAc-GD1a, GD1b, GT1a, GT1b, GQ1b) and a neutral glycolipid, asialo-GM1 (GA1), and antigens from the combination of 2 different glycolipids. Based on serial nerve conduction studies, the electrodiagnoses were as follows: 69 demyelinating subtype, 85 axonal subtypes, and 45 unclassified. Results: Significant associations were detected between acute motor axonal neuropathy subtype and IgG antibodies to GM1, GalNAc-GD1a, GA1, or LM1/GA1 complex. Reversible conduction failure was significantly associated with IgG antibodies to GM1, GalNAc-GD1a, GD1b, or complex of LM1/GA1. No significant association was demonstrated between acute inflammatory demyelinating polyneuropathy and any of the glycolipids or ganglioside complexes. Antiganglioside complex antibodies alone were detected in 7 patients (5 axonal subtype). Conclusions: The current study demonstrates that antibodies to single glycolipids and ganglioside complexes are associated with acute motor axonal neuropathy or acute motor conduction block neuropathy but not acute inflammatory demyelinating polyneuropathy. Classification of evidence: This study provides Class II evidence that antibodies to glycolipids are increased in patients with acute motor axonal neuropathy and acute motor conduction block neuropathy but not acute inflammatory demyelinating polyneuropathy. © 2014 American Academy of Neurology.

Zhang D.,Singapore Institute of Medical Biology | Zhao T.,Singapore Institute of Medical Biology | Ang H.S.,National University of Singapore | Chong P.,Singapore Institute of Medical Biology | And 4 more authors.
Genes and Development | Year: 2012

The gene expression networks governing embryonic stem cell (ESC) pluripotency are complex and finely regulated during differentiation toward specific lineages. We describe a new role for Amd1 (adenosyl methionine decarboxylase), a key enzyme in the polyamine synthesis pathway, in regulating both ESC self-renewal and differentiation to the neural lineage. Amd1 is highly expressed in ESCs and is translationally down-regulated by the neural precursor cell (NPC)-enriched microRNA miR-762 during NPC differentiation. Overexpression of Amd1 or addition of the polyamine spermine blocks ESC-to-NPC conversion, suggesting Amd1 must be down-regulated to decrease the levels of inhibitory spermine during differentiation. In addition, we demonstrate that high levels of Amd1 are required for maintenance of the ESC state. We show that forced overexpression of Amd1 in ESCs results in maintenance of high Myc levels and a delay in differentiation on removal of LIF. We propose that Amd1 is a major regulator of ESC self-renewal and that its essential role lies in its regulation of Myc levels within the cell. © 2012 by Cold Spring Harbor Laboratory Press.

Masu H.,Chiba University | Imanari M.,Chiba University
Journal of Physical Chemistry B | Year: 2012

We synthesized three series of imidazolium-based ionic liquids (ILs) containing cycloalkyl groups such as cyclopentyl, cyclohexyl, or cycloheptyl groups incorporating bis(trifluoromethanesulfonyl)amide anions and characterized them with respect to physicochemical properties and molecular reorientational dynamics. A comparison of the physicochemical properties revealed that cycloalkyl-substituted imidazolium ILs have higher densities, viscosities, and glass transition temperatures than the respective n-alkyl-substituted imidazolium ILs. Among three series, the cyclopentyl-substituted IL exhibits exceptionally lower viscosity. Observation of correlation times by 13C NMR spectroscopy revealed that a remarkably lower viscosity for the cyclopentyl-substituted IL and a considerably higher viscosity for the cyclohexyl- and cycloheptyl-substituted ones are closely related to the respective reorientational motion of the cations. The cause of these distinctions is suggested to be attributed to the difference of activation energy for the conformational interconversion of their substituents. © 2012 American Chemical Society.

Zhang J.-C.,Chiba University | Li S.-X.,Chiba University | Li S.-X.,Peking University | Hashimoto K.,Chiba University
Pharmacology Biochemistry and Behavior | Year: 2014

The N-methyl-d-aspartate (NMDA) receptor antagonist ketamine is one of the most attractive antidepressants for treatment-resistant major depressive disorder (MDD). Ketamine (or RS (±)-ketamine) is a racemic mixture containing equal parts of R (-)-ketamine and S (+)-ketamine. In this study, we examined the effects of R- and S-ketamine on depression-like behavior in juvenile mice after neonatal dexamethasone (DEX) exposure. In the tail suspension test (TST) and forced swimming test (FST), both isomers of ketamine significantly attenuated the increase in immobility time, seen in DEX-treated juvenile mice at 27 and 29 h respectively, after ketamine injections. In the 1% sucrose preference test (SPT), both isomers significantly attenuated the reduced preference for 1% sucrose consumption in DEX-treated juvenile mice, 48 h after a ketamine injection. Interestingly, when immobility times were tested by the TST and FST at day 7, R-ketamine, but not S-ketamine, significantly lowered the increases in immobility seen in DEX-treated juvenile mice. This study shows that a single dose of R-ketamine produced rapid and long-lasting antidepressant effects in juvenile mice exposed neonatally to DEX. Therefore, R-ketamine appears to be a potent and safe antidepressant relative to S-ketamine, since R-ketamine may be free of psychotomimetic side effects. © 2013 Elsevier Inc.

Husnik F.,University of South Bohemia | Nikoh N.,Chiba University | Koga R.,Japan National Institute of Advanced Industrial Science and Technology | Ross L.,University of Oxford | And 9 more authors.
Cell | Year: 2013

Summary The smallest reported bacterial genome belongs to Tremblaya princeps, a symbiont of Planococcus citri mealybugs (PCIT). Tremblaya PCIT not only has a 139 kb genome, but possesses its own bacterial endosymbiont, Moranella endobia. Genome and transcriptome sequencing, including genome sequencing from a Tremblaya lineage lacking intracellular bacteria, reveals that the extreme genomic degeneracy of Tremblaya PCIT likely resulted from acquiring Moranella as an endosymbiont. In addition, at least 22 expressed horizontally transferred genes from multiple diverse bacteria to the mealybug genome likely complement missing symbiont genes. However, none of these horizontally transferred genes are from Tremblaya, showing that genome reduction in this symbiont has not been enabled by gene transfer to the host nucleus. Our results thus indicate that the functioning of this three-way symbiosis is dependent on genes from at least six lineages of organisms and reveal a path to intimate endosymbiosis distinct from that followed by organelles. © 2013 Elsevier Inc.

Saito H.,Nippon Telegraph and Telephone | Tanaka S.,Chiba University | Shioda S.,Chiba University
IEEE Transactions on Signal Processing | Year: 2011

We investigated how to estimate the shape of a target object. For this problem, we propose pair-line composite sensor nodes consisting of multiple sensors on a pair of line segments, where each sensor generates binary information whether it detects the target object or not. We show that the proposed pair-line composite sensor nodes, which are randomly placed, can detect a certain range of angles; therefore, we also call them stochastic geometric filters. By random distribution of pair-line composite sensor nodes without GPS functions or careful placement at known locations, the information sent from the nodes enables us to estimate the boundary angles of the target object as well as its size and perimeter length. A composite sensor node can be conceptualized as between a sensor node equipped with GPS functions, or carefully placed sensors at known locations, and randomly deployed simple sensors without GPS functions. © 2011 IEEE.

Li Z.,Chiba University | Du Z.,Tsinghua National Laboratory for Information Sciences and Technology | Takahashi M.,Chiba University | Saito K.,Chiba University | Ito K.,Chiba University
IEEE Transactions on Antennas and Propagation | Year: 2012

Mutual coupling is a critical problem in the design of MIMOantennas because it deteriorates the performance ofMIMO systems, which not only affects the antenna efficiency but also influences the correlation. Therefore, in this paper, using parasitic elements to reduce mutual coupling is studied. By adding parasitic elements a double-coupling path is introduced and it can create a reverse coupling to reduce mutual coupling. As an example, a dual-slot-element antenna with parasiticmonopoles formobile terminals is described. The discussion on channel capacity shows that the antenna can be considered as a good candidate for MIMO systems. Furthermore, based on the study of current distributions, it is concluded that the technique is sensitive to relative positions between parasitic elements, and relative positions between active element and parasitic element. Finally, we also extend the technique to a tri-element antenna. © 2011 IEEE.

Bunjobpol W.,Hospital Drive | Dulloo I.,Hospital Drive | Igarashi K.,Chiba University | Concin N.,Innsbruck Medical University | And 3 more authors.
Cell Death and Differentiation | Year: 2014

Enhanced resistance to chemotherapy has been correlated with high levels of Delta-Np73 (DNp73), an anti-apoptotic protein of the p53 tumor-suppressor family which inhibits the pro-apoptotic members such as p53 and TAp73. Although genotoxic drugs have been shown to induce DNp73 degradation, lack of mechanistic understanding of this process precludes strategies to enhance the targeting of DNp73 and improve treatment outcomes. Antizyme (Az) is a mediator of ubiquitin-independent protein degradation regulated by the polyamine biosynthesis pathway. We show here that acetylpolyamine oxidase (PAOX), a catabolic enzyme of this pathway, upregulates DNp73 levels by suppressing its degradation via the Az pathway. Conversely, downregulation of PAOX activity by siRNA-mediated knockdown or chemical inhibition leads to DNp73 degradation in an Az-dependent manner. PAOX expression is suppressed by several genotoxic drugs, via selected members of the activator protein-1 (AP-1) transcription factors, namely c-Jun, JunB and FosB, which are required for stress-mediated DNp73 degradation. Finally, chemical- and siRNA-mediated inhibition of PAOX significantly reversed the resistant phenotype of DNp73-overexpressing cancer cells to genotoxic drugs. Together, these data define a critical mechanism for the regulation of DNp73 abundance, and reveal that inhibition of PAOX could widen the therapeutic index of cytotoxic drugs and overcome DNp73-mediated chemoresistance in tumors. © 2014 Macmillan Publishers Limited All rights reserved.

Fukuoka D.,Chiba University | Oto K.,Chiba University | Muro K.,Chiba University | Hirayama Y.,Tohoku University | Kumada N.,Nippon Telegraph and Telephone
Physical Review Letters | Year: 2010

Spin relaxation of two-dimensional electrons in a GaAs/AlGaAs quantum well was studied by time-resolved Kerr rotation measurements using a two-color pump and probe technique. In quantum Hall ferromagnets, the spin-wave relaxation is strongly influenced by the photogenerated Skyrmion and anti-Skyrmion pairs. By tuning the pump and probe lights to the lowest optical transition, an intrinsic filling factor dependence of spin relaxation is obtained without photogeneration of Skyrmions. The relaxation time of the spin wave presents a sharp peak at odd filling factors, accompanied by dips on both sides of it. The peculiar filling factor dependence of the spin-wave relaxation around quantum Hall ferromagnets can be explained by the interaction between the spin wave and Skyrmion. Observation of a similar feature around ν=1, 3, and 5 may suggest the existence of Skyrmions around higher odd filling factors. © 2010 The American Physical Society.

Nakajima T.,University of Toronto | Nakajima T.,Chiba University | Yasufuku K.,University of Toronto | Nakagawara A.,Chiba Cancer Center | Yoshino I.,Chiba University
Chest | Year: 2011

Background: The importance of biomarker analysis in patients with non-small cell lung cancer (NSCLC) is well known. The purpose of this study was to analyze the mutation status of multiple genes in metastatic lymph nodes obtained by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and to examine the correlation between treatments and outcomes. Methods: Genetic alterations were analyzed in metastatic hilar or mediastinal lymph nodes diagnosed by EBUS-TBNA in 156 patients with NSCLC. Epidermal growth factor receptor (EGFR) was analyzed using the peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp method (n = 156). V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (K-ras)(exons 2-3) and tumor protein 53 (p53) (exons 4-8) were analyzed by direct sequencing (n = 113). In addition, retrospective chart review was performed for clinical data analysis. Results: EGFR gene mutations were detected in 42 cases (26.9%). Twenty-three patients with EGFR mutations received gefitinib, with an overall response rate(partial response [PR]) of 54.5% and disease control rate (PR + stable disease) of 86.4% (Response Evaluation Criteria in Solid Tumors). K-ras gene mutations were detected in four cases (3.5%), and p53 gene mutations were detected in 47 cases (41.6%). Fifty-two patients underwent conventional chemotherapy (46 patients underwent platinum-based chemotherapy). Patients with p53 gene mutations showed chemoresistance (progressive disease of 42.9%, P =.0339) and a relatively poor prognosis after chemotherapy (P =.1391). Conclusions: Multigene mutation analysis can be performed in EBUS-TBNA samples of metastatic lymph nodes from patients with NSCLC. EBUS-TBNA allows genetic evaluation of tumor cells within the metastatic node, which may allow physicians to better select treatments, particularly EGFR tyrosine kinase inhibitors. © 2011 American College of Chest Physicians.

Hindmarch I.,University of Surrey | Hashimoto K.,Chiba University
Human Psychopharmacology | Year: 2010

Cognitive impairment is a primary feature of patients with major depressive disorder (MDD) and is characterised by stress-induced neural atrophy. Via alpha-adrenergic, anti-cholinergic and anti-histaminic activities, several antidepressants can cause significant counter-therapeutic cognitive impairment. Evidence is emerging of the involvement of sigma-1 receptor agonism in the mechanism of action of some antidepressants, notably fluvoxamine. Sigma-1 receptors are abundant in areas affected by depression/stress-induced cerebral atrophy and their ligands have a unique pharmacological profile; they may promote neurogenesis and initiate adaptive neural plasticity as a protection/ reaction to stress. Fluvoxamine, as a potent sigma-1 receptor agonist, has shown ameliorating effects in animal models of psychosis, depression, stress, anxiety, obsessive-compulsive disorder (OCD) and aggression and has been shown to improve cognitive impairments. In humans, fluvoxamine may repair central nervous system (CNS) atrophy and restore cognitive function. The current review explores the mechanisms through which sigma-1 receptors can modulate cognitive function and examines how antidepressant therapy with fluvoxamine may help improve cognitive outcomes in patients with depression. Copyright © 2010 John Wiley & Sons, Ltd.

Agency: GTR | Branch: NERC | Program: | Phase: Research Grant | Award Amount: 1.47M | Year: 2015

Concerns are growing about how much melting occurs on the surface of the Greenland Ice Sheet (GrIS), and how much this melting will contribute to sea level rise (1). It seems that the amount of melting is accelerating and that the impact on sea level rise is over 1 mm each year (2). This information is of concern to governmental policy makers around the world because of the risk to viability of populated coastal and low-lying areas. There is currently a great scientific need to predict the amount of melting that will occur on the surface of the GrIS over the coming decades (3), since the uncertainties are high. The current models which are used to predict the amount of melting in a warmer climate rely heavily on determining the albedo, the ratio of how reflective the snow cover and the ice surface are to incoming solar energy. Surfaces which are whiter are said to have higher albedo, reflect more sunlight and melt less. Surfaces which are darker adsorb more sunlight and so melt more. Just how the albedo varies over time depends on a number of factors, including how wet the snow and ice is. One important factor that has been missed to date is bio-albedo. Each drop of water in wet snow and ice contains thousands of tiny microorganisms, mostly algae and cyanobacteria, which are pigmented - they have a built in sunblock - to protect them from sunlight. These algae and cyanobacteria have a large impact on the albedo, lowering it significantly. They also glue together dust particles that are swept out of the air by the falling snow. These dust particles also contain soot from industrial activity and forest fires, and so the mix of pigmented microbes and dark dust at the surface produces a darker ice sheet. We urgently need to know more about the factors that lead to and limit the growth of the pigmented microbes. Recent work by our group in the darkest zone of the ice sheet surface in the SW of Greenland shows that the darkest areas have the highest numbers of cells. Were these algae to grow equally well in other areas of the ice sheet surface, then the rate of melting of the whole ice sheet would increase very quickly. A major concern is that there will be more wet ice surfaces for these microorganisms to grow in, and for longer, during a period of climate warming, and so the microorganisms will grow in greater numbers and over a larger area, lowering the albedo and increasing the amount of melt that occurs each year. The nutrient - plant food - that the microorganisms need comes from the ice crystals and dust on the ice sheet surface, and there are fears that increased N levels in snow and ice may contribute to the growth of the microorganisms. This project aims to be the first to examine the growth and spread of the microorganisms in a warming climate, and to incorporate biological darkening into models that predict the future melting of the GrIS. References 1. Sasgen I and 8 others. Timing and origin of recent regional ice-mass loss in Greenland. Earth and Planetary Science Letters, 333-334, 293-303(2012). 2. Rignot, E., Velicogna, I., van den Broeke, M. R., Monaghan, A. & Lenaerts, J. Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise. Geophys. Res. Lett. 38, L05503, doi:10.1029/2011gl046583 (2011). 3. Milne, G. A., Gehrels, W. R., Hughes, C. W. & Tamisiea, M. E. Identifying the causes of sea-level change. Nature Geosci 2, 471-478 (2009).

Kenzmedico Co. and Chiba University | Date: 2012-05-11

Provided is a stethoscopy training system which is inexpensive and has a simple configuration, without using a device which measures a respiratory operation of a simulated patient. The stethoscopy training system for this objective is formed from: a simulated stethoscope (1) having a sound acquisition unit further comprising a location display means (1d), a tube, and ear pipes; a location sensing means (2) for sensing the location of the sound acquisition unit; biological sound database (3); a biological sound reproducing means (4); and a timing display means (5) for displaying a timing of a repetition of a reproduced respiratory sound. The database retains as information biological sounds which are prerecorded from actual patients in correspondence with chest locations. The biological sound reproducing means further comprises a voice reproducing apparatus (4a), extracts prescribed biological sound information from the database according to the sound acquisition unit location which the location sensing means has sensed, and emits a reproduced biological sound from the voice reproducing apparatus, which a trainee hears via the ear pipes. The simulated patient views the timing display means and matches his or her respiratory operation to a reproduced respiratory sound.

Kondo K.-I.,Chiba University | Shibata A.,High Energy Accelerator Research Organization | Shinohara T.,Chiba University
Physics Reports | Year: 2015

The purpose of this paper is to review the recent progress in understanding quark confinement. The emphasis of this review is placed on how to obtain a manifestly gauge-independent picture for quark confinement supporting the dual superconductivity in the Yang-Mills theory, which should be compared with the Abelian projection proposed by 't Hooft. The basic tools are novel reformulations of the Yang-Mills theory based on change of variables extending the decomposition of the SU(N) Yang-Mills field due to Cho, Duan-Ge and Faddeev-Niemi, together with the combined use of extended versions of the Diakonov-Petrov version of the non-Abelian Stokes theorem for the SU(N) Wilson loop operator. Moreover, we give the lattice gauge theoretical versions of the reformulation of the Yang-Mills theory which enables us to perform the numerical simulations on the lattice. In fact, we present some numerical evidences for supporting the dual superconductivity for quark confinement. The numerical simulations include the derivation of the linear potential for static interquark potential, i.e., non-vanishing string tension, in which the "Abelian" dominance and magnetic monopole dominance are established, confirmation of the dual Meissner effect by measuring the chromoelectric flux tube between quark-antiquark pair, the induced magnetic-monopole current, and the type of dual superconductivity, etc. In addition, we give a direct connection between the topological configuration of the Yang-Mills field such as instantons/merons and the magnetic monopole. We show especially that magnetic monopoles in the Yang-Mills theory can be constructed in a manifestly gauge-invariant way starting from the gauge-invariant Wilson loop operator and thereby the contribution from the magnetic monopoles can be extracted from the Wilson loop in a gauge-invariant way through the non-Abelian Stokes theorem for the Wilson loop operator, which is a prerequisite for exhibiting magnetic monopole dominance for quark confinement. The Wilson loop average is calculated according to the new reformulation written in terms of new field variables obtained from the original Yang-Mills field based on change of variables. The Maximally Abelian gauge in the original Yang-Mills theory is also reproduced by taking a specific gauge fixing in the reformulated Yang-Mills theory. This observation justifies the preceding results obtained in the maximal Abelian gauge at least for gauge-invariant quantities for SU(2) gauge group, which eliminates the criticism of gauge artifact raised for the Abelian projection. The claim has been confirmed based on the numerical simulations. However, for SU(N) (N≥. 3), such a gauge-invariant reformulation is not unique, although the extension along the line proposed by Cho, Faddeev and Niemi is possible. In fact, we have found that there are a number of possible options of the reformulations, which are discriminated by the maximal stability group H~ of G, while there is a unique option of H~=U(1) for G= SU(2). The maximal stability group depends on the representation of the gauge group, to that the quark source belongs. For the fundamental quark for SU(3), the maximal stability group is U(2), which is different from the maximal torus group U(1). ×. U(1) suggested from the Abelian projection. Therefore, the chromomagnetic monopole inherent in the Wilson loop operator responsible for confinement of quarks in the fundamental representation for SU(3) is the non-Abelian magnetic monopole, which is distinct from the Abelian magnetic monopole for the SU(2) case. Therefore, we claim that the mechanism for quark confinement for SU(N) (N≥. 3) is the non-Abelian dual superconductivity caused by condensation of non-Abelian magnetic monopoles. We give some theoretical considerations and numerical results supporting this picture. Finally, we discuss some issues to be investigated in future studies. © 2015 Elsevier B.V.

News Article | December 6, 2016

Researchers using the Atacama Large Millimeter/submillimeter Array (ALMA) have, for the first time, achieved a precise size measurement of small dust particles around a young star through radio-wave polarization. ALMA's high sensitivity for detecting polarized radio waves made possible this important step in tracing the formation of planets around young stars. Astronomers have believed that planets are formed from gas and dust particles, although the details of the process have been veiled. One of the major enigmas is how dust particles as small as 1 micrometer aggregate to form a rocky planet with a diameter of 10 thousand kilometers. Difficulty in measuring the size of dust particles has prevented astronomers from tracing the process of dust growth. Akimasa Kataoka, a Humboldt Research Fellow stationed at Heidelberg University and the National Astronomical Observatory of Japan, tackled this problem. He and his collaborators have theoretically predicted that, around a young star, radio waves scattered by the dust particles should carry unique polarization features. He also noticed that the intensity of polarized emissions allows us to estimate the size of dust particles far better than other methods. To test their prediction, the team led by Kataoka observed the young star HD 142527 with ALMA and discovered, for the first time, the unique polarization pattern in the dust disk around the star. As predicted, the polarization has a radial direction in most parts of the disk, but at the edge of the disk, the direction is flipped perpendicular to the radial direction. Comparing the observed intensity of the polarized emissions with the theoretical prediction, they determined that the size of the dust particles is at most 150 micrometers. This is the first estimation of the dust size based on polarization. Surprisingly, this estimated size is more than 10 times smaller than previously thought. "In the previous studies, astronomers have estimated the size based on radio emissions assuming hypothetical spherical dust particles," explains Kataoka. "In our study, we observed the scattered radio waves through polarization, which carries independent information from the thermal dust emission. Such a big difference in the estimated size of dust particles implies that the previous assumption might be wrong." The team's idea to solve this inconsistency is to consider fluffy, complex-shaped dust particles, not simple spherical dust. In the macroscopic view, such particles are indeed large, but in the microscopic view, each small part of a large dust particle scatters radio waves and produces unique polarization features. According to the present study, astronomers obtain these "microscopic" features through polarization observations. This idea might prompt astronomers to reconsider the previous interpretation of observational data. "The polarization fraction of radio waves from the dust disk around HD 142527 is only a few percent. Thanks to ALMA's high sensitivity, we have detected such a tiny signal to derive information about the size and shape of the dust particles," said Kataoka. "This is the very first step in the research on dust evolution with polarimetry, and I believe the future progress will be full of excitement." Reference: "Millimeter Polarization Observation of the Protoplanetary Disk around HD 142527," A. Kataoka et al., 2016 Nov. 10, Astrophysical Journal Letters [, preprint:]. The research team members are Akimasa Kataoka (Humboldt Research Fellowship for Postdoctoral Researchers / Heidelberg University / National Astronomical Observatory of Japan / former Postdoctoral Fellowship for Research Abroad at Japan Society for Promoting Science), Takashi Tsukagoshi (Ibaraki University), Munetake Momose (Ibaraki University), Hiroshi Nagai (National Astronomical Observatory of Japan), Takayuki Muto (Kogakuin University), Cornelis P. Dullemond (Heidelberg University), Adriana Pohl (Heidelberg University / Max Planck Institute for Astronomy), Misato Fukagawa (Nagoya University), Hiroshi Shibai (Osaka University), Tomoyuki Hanawa (Chiba University), Koji Murakawa (Osaka Sangyo University) This research was supported by a Grant-in-Aid from the Japan Society for the Promotion of Science and the Ministry of Education, Culture, Sports, Science and Technology, Japan (No. 23103004, 15K17606, 26800106). The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA. Please follow SpaceRef on Twitter and Like us on Facebook.

Nakata T.,Chiba University | Liu H.,Chiba University | Liu H.,Shanghai JiaoTong University
Proceedings of the Royal Society B: Biological Sciences | Year: 2012

Insect wings are deformable structures that change shape passively and dynamically owing to inertial and aerodynamic forces during flight. It is still unclear how the three-dimensional and passive change of wing kinematics owing to inherent wing flexibility contributes to unsteady aerodynamics and energetics in insect flapping flight. Here, we perform a systematic fluid-structure interaction based analysis on the aerodynamic performance of a hovering hawkmoth, Manduca, with an integrated computational model of a hovering insect with rigid and flexible wings. Aerodynamic performance of flapping wings with passive deformation or prescribed deformation is evaluated in terms of aerodynamic force, power and efficiency. Our results reveal that wing flexibility can increase downwash in wake and hence aerodynamic force: first, a dynamic wing bending is observed, which delays the breakdown of leading edge vortex near the wing tip, responsible for augmenting the aerodynamic force-production; second, a combination of the dynamic change of wing bending and twist favourably modifies the wing kinematics in the distal area, which leads to the aerodynamic force enhancement immediately before stroke reversal. Moreover, an increase in hovering efficiency of the flexible wing is achieved as a result of the wing twist. An extensive study of wing stiffness effect on aerodynamic performance is further conducted through a tuning of Young's modulus and thickness, indicating that insect wing structures may be optimized not only in terms of aerodynamic performance but also dependent on many factors, such as the wing strength, the circulation capability of wing veins and the control of wing movements. © 2011 The Royal Society.

Nakamura J.,Chiba University | Saisu T.,Chiba Childrens Hospital | Yamashita K.,Funabashi Central Hospital | Suzuki C.,Matsudo City Hospital | And 2 more authors.
Arthritis and Rheumatism | Year: 2010

Objective. To clarify whether age at the time of the initial administration of corticosteroids is a risk factor for corticosteroid-associated osteonecrosis in children with systemic lupus erythematosus (SLE), using magnetic resonance imaging (MRI). Methods. From 1986 to 2007, MRI was used to prospectively study 676 joints, including 72 joints (36 hips and 36 knees) in 18 pediatric patients with SLE (<15 years old), 100 joints (50 hips and 50 knees) in 25 adolescent patients with SLE (15-20 years old), and 504 joints (252 hips and 252 knees) in 126 adult patients with SLE (>20 years old), beginning just after corticosteroid administration, for at least 1 year. The followup rate was 100%. Results. In pediatric patients, osteonecrosis developed in 4 joints (6%; all hips). In adolescent patients, osteonecrosis developed in 49 joints (49%; 18 hips and 31 knees). In adult patients, osteonecrosis developed in 207 joints (41%; 95 hips and 112 knees). The rate of osteonecrosis was significantly lower in pediatric patients than in adolescent or adult patients (P = 0.0001). Logistic regression analysis revealed that adolescent and adult patients had a significantly higher risk for osteonecrosis compared with pediatric patients, with an odds ratio of 10.3 (P < 0.0001). The youngest patients with osteonecrosis in the hip and knee were 14.9 years old and 15.5 years old, respectively. Osteonecrosis did not develop in patients younger than age 14 years. Conclusion. Our results suggest that age at the time of the initial administration of corticosteroids is associated with osteonecrosis in pediatric patients with SLE. © 2010, American College of Rheumatology.

Hanawa T.,Chiba University | Tomisaka K.,Japan National Astronomical Observatory | Tomisaka K.,Graduate University for Advanced Studies
Astrophysical Journal | Year: 2015

We have constructed two types of analytical models for an isothermal filamentary cloud supported mainly by magnetic tension. The first one describes an isolated cloud while the second considers filamentary clouds spaced periodically. Both models assume that the filamentary clouds are highly flattened. The former is proved to be the asymptotic limit of the latter in which each filamentary cloud is much thinner than the distance to the neighboring filaments. We show that these models reproduce the main features of the 2D equilibrium model of Tomisaka for a filamentary cloud threaded by a perpendicular magnetic field. It is also shown that the critical mass to flux ratio is , where M, Φ and G denote the cloud mass, the total magnetic flux of the cloud, and the gravitational constant, respectively. This upper bound coincides with that for an axisymmetric cloud supported by poloidal magnetic fields. We apply the variational principle for studying the Jeans instability of the first model. Our model cloud is unstable against fragmentation as well as the filamentary clouds threaded by a longitudinal magnetic field. The fastest growing mode has a wavelength several times longer than the cloud diameter. The second model describes quasi-static evolution of a filamentary molecular cloud by ambipolar diffusion. © 2015. The American Astronomical Society. All rights reserved..

Hatano M.,Nippon Steel & Sumitomo Metal Corporation | Fujinami M.,Chiba University | Arai K.,Chiba University | Fujii H.,Nippon Steel & Sumitomo Metal Corporation | Nagumo M.,Waseda University
Acta Materialia | Year: 2014

Hydrogen embrittlement of austenitic stainless steels has been examined with respect to deformation microstructures and lattice defects created during plastic deformation. Two types of austenitic stainless steels, SUS 304 and SUS 316L, uniformly hydrogen-precharged to 30 mass ppm in a high-pressure hydrogen environment, are subjected to tensile straining at room temperature. A substantial reduction of tensile ductility appears in hydrogen-charged SUS 304 and the onset of fracture is likely due to plastic instability. Fractographic features show involvement of plasticity throughout the crack path, implying the degradation of the austenitic phase. Electron backscatter diffraction analyses revealed prominent strain localization enhanced by hydrogen in SUS 304. Deformation microstructures of hydrogen-charged SUS 304 were characterized by the formation of high densities of fine stacking faults and ε-martensite, while tangled dislocations prevailed in SUS 316L. Positron lifetime measurements have revealed for the first time hydrogen-enhanced creation of strain-induced vacancies rather than dislocations in the austenitic phase and more clustering of vacancies in SUS 304 than in SUS 316L. Embrittlement and its mechanism are ascribed to the decrease in stacking fault energies resulting in strain localization and hydrogen-enhanced creation of strain-induced vacancies, leading to premature fracture in a similar way to that proposed for ferritic steels. © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Kuto K.,University of Electro - Communications | Osaki K.,Kwansei Gakuin University | Sakurai T.,Chiba University | Tsujikawa T.,University of Miyazaki
Physica D: Nonlinear Phenomena | Year: 2012

Mimura and one of the authors (1996) proposed a mathematical model for the pattern dynamics of aggregating regions of biological individuals possessing the property of chemotaxis. For this model, Tello and Winkler (2007) [22] obtained infinitely many local branches of nonconstant stationary solutions bifurcating from a positive constant solution, while Kurata et al. (2008) numerically showed several spatio-temporal patterns in a rectangle. Motivated by their work, we consider some qualitative behaviors of stationary solutions from global and local (bifurcation) viewpoints in the present paper. First we study the asymptotic behavior of stationary solutions as the chemotactic intensity grows to infinity. Next we construct local bifurcation branches of stripe and hexagonal stationary solutions in the special case when the habitat domain is a rectangle. For this case, the directions of the branches near the bifurcation points are also obtained. Finally, we exhibit several numerical results for the stationary and oscillating patterns. © 2012 Elsevier B.V. All rights reserved.

Uncini A.,University of Chieti Pescara | Kuwabara S.,Chiba University
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2015

Peripheral nerve diseases are traditionally classified as demyelinating or axonal. It has been recently proposed that microstructural changes restricted to the nodal/paranodal region may be the key to understanding the pathophysiology of antiganglioside antibody mediated neuropathies. We reviewed neuropathies with different aetiologies (dysimmune, inflammatory, ischaemic, nutritional, toxic) in which evidence from nerve conductions, excitability studies, pathology and animal models, indicate the involvement of the nodal region in the pathogenesis. For these neuropathies, the classification in demyelinating and axonal is inadequate or even misleading, we therefore propose a new category of nodopathy that has the following features: (1) it is characterised by a pathophysiological continuum from transitory nerve conduction block to axonal degeneration; (2) the conduction block may be due to paranodal myelin detachment, node lengthening, dysfunction or disruption of Na+ channels, altered homeostasis of water and ions, or abnormal polarisation of the axolemma; (3) the conduction block may be promptly reversible without development of excessive temporal dispersion; (4) axonal degeneration, depending on the specific disorder and its severity, eventually follows the conduction block. The term nodopathy focuses to the site of primary nerve injury, avoids confusion with segmental demyelinating neuropathies and circumvents the apparent paradox that something axonal may be reversible and have a good prognosis. © 2015, BMJ Publishing Group. All rights reserved.

Liu W.,Chiba University | Yamazaki F.,Chiba University | Vu T.T.,KTH Royal Institute of Technology
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2011

A new method has been developed to automatically extract moving vehicles and subsequently determine their speeds from a pair of QuickBird (QB) panchromatic (PAN) and multispectral (MS) images. Since the PAN and MS sensors of QB have a slight time lag (approximately 0.2 s), the speed of a moving vehicle can be determined from the difference in the positions of the vehicle observed in the PAN and MS images due to the time lag. An object-based approach can be used to extract a vehicle from the PAN image, which has a resolution of 0.6 m. However, it is difficult to accurately extract the position of a vehicle from an MS image because its resolution is 2.4 m. Thus, an area correlation method is proposed to determine the location of a vehicle from an MS image at a sub-pixel level. The speed of the moving vehicle can then be calculated by using the vehicle extraction results. This approach was tested on several parts of a QB image covering central Tokyo, Japan, and the accuracy of the results is demonstrated in this study. © 2008 IEEE.

Inoue S.,Mitsubishi Group | Tsumura N.,Chiba University
6th European Conference on Colour in Graphics, Imaging, and Vision 2012, CGIV 2012 | Year: 2012

Glossiness is one of the important qualities for printing paper. Glossiness is a specular reflection phenomenon in aspect of optics. Therefore, there are various methods of evaluating specular reflection phenomenon. When a person is evaluating the glossiness of paper, it is quite popular to visually inspect the glossiness by the sharpness of the reflected light image. In this paper, it is shown that this visual inspection can be expressed by a transfer function of specular reflection image. First, we discuss the possible use of point spread function of specular reflection (SR-PSF). A technique for measuring SR-PSF of paper is proposed. The measurement principle is a collimator method. This method has been used for the PSF measurement of typical transmittance optical system. We have developed the apparatus to measure SR-PSF. The SR-PSFs were measured for paper samples. The experimental results showed that the measured SR-PSF works as a transfer function for specular reflection image. Second, we show that the apparatus used for measuring SR-PSF also works as a goniophotometer within a narrow solid angle. It is shown that the reflection angle calculated theoretically meets well with that experimentally obtained. That is, a distribution of reflection angle can be calculated using SR-PSF data. It is thought that the spreading of specular reflection observed on paper samples is caused by the distribution of surface normals. Our results showed that SR-PSF and gonio-reflectance distribution are one phenomenon expressed in two different physical concepts. Our future study will be focused on new reflection model for computer graphics.

Lewis J.C.,Indiana University of Pennsylvania | Byrne T.B.,University of Connecticut | Kanagawa K.,Chiba University
Geochemistry, Geophysics, Geosystems | Year: 2013

Detailed analyses of cores from two drill sites landward of the Nankai trough provide constraints on the evolution of stress across the SW Japan subduction zone. Core-scale faults at Sites C0001 and C0002 suggest changing stress geometries that shed light on mechanical coupling across this plate boundary. Normal faults dominate the record of brittle strain in both the sedimentary cover and the upper accretionary prism, and these cut older shear zones and vein structures. Based on cross-cutting relations normal faults postdate thrust faults with the latter interpreted to be inactive. The normal faults, in contrast, are consistent with contemporary stress proxies such as borehole breakout and anelastic strain recovery data. Stress inversion for faults that are restored to original orientations using paleomagnetic data reveal that thrusting has accommodated trench subperpendicular shortening associated with interplate coupling. This phase of deformation is overprinted by normal faulting attributed to mechanical decoupling of the upper plate from the lower plate in response to the underplating of anomalously weak sediments between an out-of-sequence thrust and the décollement. These observations suggest that core-scale faults record a stress history that is, to date, not apparent from in situ stress proxies such as borehole breakout data or anelastic strain recovery data. We conclude that the brittle faults provide a unique record of changing stress conditions that can be recognized only through coring. ©2013. American Geophysical Union. All Rights Reserved.

Akimoto A.,Nara Women's University | Hirano Y.M.,Chiba University | Sakai A.,Nara Women's University | Yusa Y.,Nara Women's University
Marine Biology | Year: 2014

Sacoglossans use chloroplasts taken from algal food for photosynthesis (kleptoplasty), but the adaptive significance of this phenomenon remains unclear. Two con-generic sacoglossans (Elysia trisinuata and E. atroviridis) were collected in 2009-2011 from Shirahama (33.69°N, 135.34°E) and Mukaishima (34.37°N, 133.22°E), Japan, respectively. They were individually maintained for 16 days under four experimental conditions (combination of light/dark and with/without food), and their survival rate and relative (=final/initial) weights were measured. Both light and food had positive effects on the survival in E. trisinuata, whereas no positive effects of light or food on survival were detected in E. atroviridis. Both light and food had positive effects on relative weights in both species, but light had smaller effects than food. A significant interaction term between light and food was detected in E. trisinuata (but not in E. atroviridis) in that only the presence of both resulted in weight gains. This result suggests that E. trisinuata can obtain sufficient additional energy from photosynthesis for sustaining growth when fresh chloroplasts are continuously supplied from algal food. In addition, fluorescence yield measurements showed that unfed individuals of both E. trisinuata and E. atroviridis lost photosynthetic activity soon (<4 and 4-8 days, respectively). In conclusion, photosynthesis may function to obtain supplementary nutrition for sustaining growth when food is available in sacoglossans with short-term functional kleptoplasty. © 2014 Springer-Verlag Berlin Heidelberg.

Nakamura Y.,University of Michigan | Franchi L.,University of Michigan | Kambe N.,Chiba University | Meng G.,CAS Shanghai Institutes for Biological Sciences | And 2 more authors.
Immunity | Year: 2012

Cryopyrin-associated periodic syndromes (CAPS) are caused by aberrant interleukin-1β (IL-1β) production induced by mutations in the NLRP3 protein in humans, but the mechanisms involved remain poorly understood. Using a mouse model, we show a role for the indigenous microbiota and mast cells (MCs) in skin disease associated with mutant Nlrp3 protein. Unlike normal cells, MCs expressing mutant Nlrp3 produced IL-1β in response to lipopolysaccharide or tumor necrosis factor-α (TNF-α). In neonatal mice, the microbiota induced TNF-α and IL-1β and promoted skin disease. MC deficiency greatly reduced disease in Nlrp3 mutant mice, and reconstitution of MC-deficient mice with mutant MCs restored skin disease, which required the expression of IL-1β in MCs. Surprisingly, neutralization of TNF-α abrogated IL-1β production and skin disease in neonatal Nlrp3 mutant mice, but not in affected adult mice. Thus, the microbiota and MCs initiate cellular events leading to dysregulated IL-1β production and skin inflammation in neonatal mice with the CAPS-associated Nlrp3 mutation. © 2012 Elsevier Inc.

Ding B.,Shanghai JiaoTong University | Zhang Z.,Shanghai JiaoTong University | Liu Y.,Shanghai JiaoTong University | Sugiya M.,Nippon Chemical Industrial Co. | And 3 more authors.
Organic Letters | Year: 2013

A pincer-Pd complex was utilized in the chemoselective transfer hydrogenation of α,β-unsaturated ketones using n-BuOH as a hydrogen source and solvent. Good to excellent yields were obtained for various substrates even with reducible groups. Based on deuterium-labeling experiments, the reaction mechanism is proposed to occur via a pincer-Pd-hydride intermediate. © 2013 American Chemical Society.

Tatsuno I.,Chiba University | Sugiyama T.,Shimoshizu National Hospital
Diabetes Research and Clinical Practice | Year: 2011

High-dose glucocorticoid was associated with new-onset diabetes mellitus (NODM) with a high prevalence during the early treatment period. Glucocorticoid-induced NODM was an independent risk factor for clinical vertebral fracture during high-dose glucocorticoid treatment in Chiba-Shimoshizu Rheumatic Cohort of 20 years in Japan. © 2011 Elsevier Ireland Ltd.

Nakata T.,Chiba University | Liu H.,Chiba University | Liu H.,Shanghai JiaoTong University
Journal of Computational Physics | Year: 2012

We present a fluid-structure interactions (FSI) model of insect flapping flight with flexible wings. This FSI-based model is established by loosely coupling a finite element method (FEM)-based computational structural dynamic (CSD) model and a computational fluid dynamic (CFD)-based insect dynamic flight simulator. The CSD model is developed specifically for insect flapping flight, which is capable to model thin shell structures of insect flexible wings by taking into account the distribution and anisotropy in both wing morphology involving veins, membranes, fibers and density, and in wing material properties of Young's modulus and Poisson's ratios. The insect dynamic flight simulator that is based on a multi-block, overset grid, fortified Navier-Stokes solver is capable to integrate modeling of realistic wing-body morphology, realistic flapping-wing and body kinematics, and unsteady aerodynamics in flapping-wing flights. Validation of the FSI-based aerodynamics and structural dynamics in flexible wings is achieved through a set of benchmark tests and comparisons with measurements, which contain a heaving spanwise flexible wing, a heaving chordwise-flexible wing with a rigid teardrop element, and a realistic hawkmoth wing rotating in air. A FSI analysis of hawkmoth hovering with flapping flexible wings is then carried out and discussed with a specific focus on the in-flight deformation of the hawkmoth wings and hovering aerodynamic performances with the flexible and rigid wings. Our results demonstrate the feasibility of the present FSI model in accurately modeling and quantitatively evaluating flexible-wing aerodynamics of insect flapping flight in terms of the aerodynamic forces, the power consumption and the efficiency. © 2011 Elsevier Inc.

Nakada H.,Chiba University | Sugiura K.,Chiba University | Margueron J.,University Paris - Sud | Margueron J.,University Claude Bernard Lyon 1
Physical Review C - Nuclear Physics | Year: 2013

Applying the semirealistic NN interactions that include a realistic tensor force to the Hartree-Fock calculations, we investigate tensor-force effects on the single-particle levels in Ca isotopes. The semirealistic interactions successfully describe the experimental difference between É(p1s 1/2) and É(p0d3/2) (denoted by ΔÉ 13) both at 40Ca and 48Ca, confirming the importance of the tensor force. The tensor force plays a role in the N dependence of ΔÉ 13 also in neutron-rich Ca nuclei. While the p1s1/2- p0d3/2 inversion is predicted in heavier Ca nuclei as in 48Ca, it takes place only for N≥46, delayed by the tensor force. We further investigate the possibility of proton bubble structure in Ar, which is suggested by the p1s1/2-p0d3/2 inversion in 48Ca and more neutron rich Ca nuclei, by using spherical Hartree-Fock-Bogolyubov calculations. Even with the inversion at 48Ca the pair correlation prohibits prominent bubble distribution in 46Ar. Bubble structure in Ar is unlikely also near the neutron drip line because of either unboundness or deformation. However, 34Si remains a candidate for proton bubble structure, owing to the large shell gap between p1s1/2 and p0d5/2. © 2013 American Physical Society.

Matsushima M.,Chiba University | Choi W.-J.,Chonnam National University | Chang S.X.,University of Alberta
Plant and Soil | Year: 2012

Background and aims: Canada bluejoint grass is a strong competitor for water and N against young white spruce trees in regenerating boreal forests in moist habitats. We investigated foliar δ13C and δ15N responses of white spruce to understory removal and N fertilization to infer treatment effects on soil water and N dynamics. Methods: An experiment with understory removal and N fertilization as the main and split-plot treatments was conducted in a 13-year-old white spruce plantation in the boreal region for 2 years. Soil N availability, gravimetric soil moisture content, tree growth, foliar C and N concentrations, and foliar δ13C and δ15N values were determined. Results: Foliar δ13C was increased by understory removal in the second year and by N fertilization in the first year. There was a positive (P < 0. 01) relationship between foliar δ13C and N concentration, suggesting that understory removal and N fertilization improved tree growth via increased N availability and thus increased carboxylation rate of photosynthesis. The positive correlation (P < 0. 01) of foliar δ15N with foliar N concentration and with available soil N indicated that understory removal and N fertilization facilitated N isotope fractionation accompanying increased soil N turnover. Conclusions: Foliar δ13C and its relationship with other variables suggested that understory removal and N fertilization improved white spruce growth mainly through enhanced carboxylation rate due to greater N availability rather than increased stomatal conductance. Specifically, understory removal and N fertilization increased soil N availability and subsequently induced N loss from the system, leading to a higher N concentration and δ15N in the foliage. Control of competing vegetation and N fertilization could be used as management tools to reduce N limitation. © 2012 Springer Science+Business Media B.V.

Shirota H.,Chiba University | Fukazawa H.,Chiba University | Fujisawa T.,Chiba University | Wishart J.F.,Brookhaven National Laboratory
Journal of Physical Chemistry B | Year: 2010

In this study, we have investigated the heavy atom substitution effects on the ultrafast dynamics in nonaromatic cation-based ionic liquids, as well as the static physical properties such as shear viscosity, surface tension, glass transition temperature, and melting point. Phosphonium-based ionic liquids show lower shear viscosities and lower glass transition temperatures than their corresponding ammonium-based ionic liquids. We have also examined the substitution of a (2-ethoxyethoxy)ethyl group for an octyl group in ammonium and phosphonium cations and found that the (2-ethoxyethoxy)ethyl group reduces the shear viscosity and increases the surface tension. From the results of the ultrafast dynamics, including intra- and interionic vibrations and reorientational relaxation in the ammonium- and phosphonium-based ionic liquids measured by means of femtosecond optically heterodyne-detected Raman-induced Kerr spectroscopy, we have found that the first moment of low-frequency Kerr spectrum, omitting the contributions of clear intraionic vibrational modes, correlates to the square root of surface tension divided by density. This fact indicates that heavy atom substitution in ionic liquids provides a weaker interionic interaction arising from the larger ionic volume. On the other hand, the ether group in the cations gives the stronger interionic interaction but with a more flexible and/or less segregated nature in the ILs than the alkyl group. © 2010 American Chemical Society.

Yagi R.,National Institute of Allergy and Infectious Diseases | Yagi R.,Chiba University | Zhong C.,National Institute of Allergy and Infectious Diseases | Northrup D.L.,U.S. National Institutes of Health | And 10 more authors.
Immunity | Year: 2014

Innate lymphoid cells (ILCs) are critical in innate immune responses to pathogens and lymphoid organ development. Similar to CD4+ T helper (Th) cell subsets, ILC subsets positive for interleukin-7 receptor α (IL-7Rα) produce distinct sets of effector cytokines. However, the molecular control of IL-7Rα+ ILC development and maintenance is unclear. Here, we report that GATA3 was indispensable for the development of all IL-7Rα+ ILC subsets and Tcells but was not required for the development of classical natural killer cells. Conditionally Gata3-deficient mice had no lymph nodes and were susceptible to Citrobactor rodentium infection. After the ILCs had fully developed, GATA3 remained important for the maintenance and functions of ILC2s. Genome-wide gene expression analyses indicated that GATA3 regulated a similar set of cytokines and receptors in Th2 cells and ILC2s, but not in ILC3s. Thus, GATA3 plays parallel roles in regulating the development and functions of CD4+ Tcells and IL-7Rα+ ILCs. © 2014 Elsevier Inc.

Chiba University and Fuso Pharmaceutical Industries Ltd. | Date: 2010-07-14

The invention relates to a stable bicarbonate ion-containing drug solution, particularly a bicarbonate-containing drug solution for dialysis in which the stability has been improved by the presence of a phosphate ion. Further, the invention relates to a drug solution for acute blood purification, particularly a dialysate and a substitution liquid for acute blood purification to be mixed before use containing the drug solution. Still further, the invention relates to a dialysate and a substitution liquid for acute blood purification to be mixed before use in which the formation of insoluble fine particles or precipitates is prevented for a long time after mixing and with which hypokalemeia and hypophosphatemia are not caused.

Japan Eco Science Co., Chiba University, Kanazawa University, National Fisheries University, Miroku Co. and Keiyo Plant Engineering Co. | Date: 2013-02-13

To provide a mixture, a dissolving solution and a pharmaceutical agent, which contain a thermophilic microorganism to make it possible to regulate a mucous membrane immune system gene cluster and metabolism-related gene clusters of the intestines and the liver. Each of them is prepared by fermentation of an organic material containing a thermophilic microorganism at a temperature of 50 C or more and 90 C or less. By being administered to the animal, it regulates at least one of a mucous membrane immune system gene cluster, a metabolism-related gene cluster in the intestines, and a metabolism-related gene cluster in the liver of the animal. The microorganism includes at least one species of the genus Bacillus, Oceanobacillus, Paenibacillus, Anoxybacillus, Lysinibacillus, Methanopyrus, Geogemma, Pyrolobus, Pyrodictium, Hyperthermus, Pyrococcus, Pyrobaculum, Thermococcus, Aeropyrum, Aquifex, Thermotoga, Thermodesulfobacterium, Thermus, Geobacillus, and Thermomyces.

Riken, Chiba University and Mitsubishi Group | Date: 2013-05-01

In a coated high-temperature superconducting wire (1) in which a superconducting yttrium-based wire (high-temperature superconducting wire) (2) having a rectangular cross section is coated by an insulating layer (6), the insulating layer (6) is an electrodeposited film made of block copolymerized polyimide which contains siloxane bonds in a polyimide main chain and which has molecules with anionic groups. A coil formed from the superconducting yttrium-based wire (2) is impregnated with epoxy resin, and the epoxy resin is cured. The coil is configured such that the epoxy resin is completely separated from the superconducting yttrium-based wire (2) by the insulating layer (6).

Riken, Mitsubishi Group and Chiba University | Date: 2012-10-23

In a coated high-temperature superconducting wire 1 in which a superconducting yttrium-based wire (high-temperature superconducting wire) 2 having a rectangular cross section is coated by an insulating layer 6, the insulating layer 6 is an electrodeposited film made of block copolymerized polyimide which contains siloxane bonds in a polyimide main chain and which has molecules with anionic groups. A coil formed from the superconducting yttrium-based wire 2 is impregnated with epoxy resin, and the epoxy resin is cured. The coil is configured such that the epoxy resin is completely separated from the superconducting yttrium-based wire 2 by the insulating layer 6.

GeneFrontier Corporation and Chiba University | Date: 2013-04-23

The present invention provides an antibody that specifically binds to human CD69, has an activity to suppress allergic inflammation, and has cross-reactivity with mouse CD69. In addition, the present invention provides an antibody having high binding affinity for human CD69 and an activity to suppress allergic inflammations. The antibody of the present invention can be a human antibody.

The detection of a non-alcoholic steatohepatitis patient and the accurate discrimination between a normal person and a non-alcoholic steatohepatitis patient can be achieved by measuring alanine-glyoxylate amino transferase in a sample.

Japan Eco Science Co., Chiba University, Kanazawa University, National Fisheries University, Miroku Co. and Keiyo Plant Engineering Co. | Date: 2015-07-09

To provide a mixture, a dissolving solution and a pharmaceutical agent, which contain a thermophilic microorganism to make it possible to regulate a mucous membrane immune system gene cluster and metabolism-related gene clusters of the intestines and the liver. Each of them is prepared by fermentation of an organic material containing a thermophilic microorganism at a temperature of 50 C. or more and 90 C. or less. By being administered to the animal, it regulates at least one of a mucous membrane immune system gene cluster, a metabolism-related gene cluster in the intestines, and a metabolism-related gene cluster in the liver of the animal. The microorganism includes at least one species of the genus Bacillus, Oceanobacillus, Paenibacillus, Anoxybacillus, Lysinibacillus, Methanopyrus, Geogemma, Pyrolobus, Pyrodictium, Hyperthermus, Pyrococcus, Pyrobaculum, Thermococcus, Aeropyrum, Aquifex, Thermotoga, Thermodesulfobacterium, Thermus, Geobacillus, and Thermomyces.

GeneFrontier Corporation and Chiba University | Date: 2015-03-04

The present invention provides an antibody that specifically binds to human CD69, has an activity to suppress allergic inflammation, and has cross-reactivity with mouse CD69. In addition, the present invention provides an antibody having high binding affinity for human CD69 and an activity to suppress allergic inflammations. The antibody of the present invention can be a human antibody.

The detection of a non-alcoholic steatohepatitis patient and the accurate discrimination between a normal person and a non-alcoholic steatohepatitis patient can be achieved by measuring alanine-glyoxylate amino transferase in a sample.

Chiba University and Fuso Pharmaceutical Industries Ltd. | Date: 2014-05-07

The invention relates to a stable bicarbonate ion-containing drug solution, particularly a bicarbonate-containing drug solution for dialysis in which the stability has been improved by the presence of a phosphate ion. Further, the invention relates to a drug solution for acute blood purification, particularly a dialysate and a substitution liquid for acute blood purification to be mixed before use containing the drug solution. Still further, the invention relates to a dialysate and a substitution liquid for acute blood purification to be mixed before use in which the formation of insoluble fine particles or precipitates is prevented for a long time after mixing and with which hypokalemeia and hypophosphatemia are not caused.

Uncini A.,University of Chieti Pescara | Kuwabara S.,Chiba University
Clinical Neurophysiology | Year: 2012

Electrophysiology plays a determinant role in Guillain-Barré syndrome (GBS) diagnosis, classification of the subtypes and in establishing prognosis. In the last three decades, different electrodiagnostic criteria sets have been proposed for acute inflammatory demyelinating neuropathy (AIDP), acute motor axonal neuropathy (AMAN) and acute motor and sensory axonal neuropathy (AMSAN). Criteria sets for AIDP varied for the parameters indicative of demyelination considered, for the cut-off limits and the number of required abnormalities (all a priori established) showing different sensitivities. Criteria sets for AMAN and AMSAN were proposed on the initial assumption that these subtypes were pathologically characterised by simple axonal degeneration. However, some AMAN patients show transient conduction block/slowing in intermediate and distal nerve segments, mimicking demyelination but without the development of abnormal temporal dispersion, named reversible conduction failure (RCF). The lack of distinction between RCF and demyelinating conduction block leads to fallaciously classify AMAN patients with RCF as AIDP or AMAN with axonal degeneration. Serial electrophysiological studies are mandatory for proper diagnosis of GBS subtypes, identification of pathophysiological mechanisms and prognosis. More reliable electrodiagnostic criteria should be devised to distinguish axonal and demyelinating subtypes of GBS, taking into consideration the RCF pattern and focussing on temporal dispersion. © 2012 International Federation of Clinical Neurophysiology.

News Article | August 22, 2016

A proposed technique provides a simple and computationally inexpensive method for enhancing the spatial resolution and reducing the speckle noise of reconstructed images. The process of computer holography involves the digital generation of holographic interference patterns. This technique is used in a wide range of applications, such as in 3D displays,1 projectors,2, 3 diffractive optical elements,4 and encryption.5 The calculation of holograms from 2D and 3D objects generally requires the addition of a random phase to widely diffuse the object light (which mainly comprises low-frequency components of narrow-angle object light). This approach is illustrated in Figure 1, where an original image—see Figure 1(a)—and image reconstructions from holograms generated with and without the random phase are shown. When the random phase is not used—see Figure 1(b)—it is nearly impossible for the original image to be retrieved in the reconstruction. This is because the narrow-spreading object light means that it cannot be recorded on the hologram. In contrast, when the random phase is used—see Figure 1(c)—the reconstructed hologram retrieves the original image well. Although the random phase technique has been used in computer holography since the 1960s,6 it unfortunately leads to a considerable amount of speckle noise in the reconstructed image. Figure 1. Illustration of the random phase technique for computer holography. An original image is shown in (a), along with reconstructions that are generated—(b) without and (c) with the random phase—from holograms of the original images. In the currently available computationally efficient methods, the object light that is processed via the random phase method is uncontrollable, and it leads to the speckle noise and to the degradation of the spatial resolution of the reconstructed image. It is possible to use iterative optimization methods, e.g., the Gerchberg–Saxton algorithm,7 to reduce the speckle noise and improve the spatial resolution of the holograms, but these methods are time-consuming. The development of new methods for obtaining high-quality images via computer holography is therefore greatly desired. We have recently reported a simple and computationally inexpensive method known as ‘random phase-free computer holography’ with which we can drastically reduce the speckle noise and enhance the image quality.8–13 We achieve this by multiplying the object light with the virtual convergence light. The effectiveness of our method means that our reconstruction—see Figure 2(a)—of the image in Figure 1(a) has lower speckle noise than in the reconstructions of Figure 1(b) or (c). We also demonstrate—see Figure 2(b) and (c)—that the spatial resolution achieved with our proposed method is better than that of the random phase method. Figure 2. Illustrating the effectiveness of the proposed random phase-free computer holography technique. (a) A reconstructed image—from the original, in Figure Illustrating the effectiveness of the proposed random phase-free computer holography technique. (a) A reconstructed image—from the original, in Figure 1 (a)—generated using this approach has low speckle noise. Images of the USAF1951 test target obtained using (b) the random phase method and (c) the proposed random phase-free method. Our simple proposed method involves the multiplication of the object with the virtual convergence light, followed by the calculation of numerical diffraction from the object (see Figure 3). The complex amplitude of the object light, u (x , y ), on the image plane is multiplied using the convergence light, w(x , y ), which is given by: where λ is the wavelength, and f is the focal length (which is equal to z +z ). The distance between the focus point of the convergence light and the hologram, z , is set to the distance at which the hologram just fits in the cone of the convergence light, and z is the distance between the object and the hologram. We derive the value of f from a simple geometric relation, S /2: S /2=z : f , where the areas of the image and the hologram are given by S ×S and S ×S , respectively. Figure 3. The setup of the calculation involved in the proposed phase-free method. f : Focal length. z and z : Distance between the focus point of the convergence light and the hologram, and between the object, u (x , y ), and the hologram, respectively. Dimensions of the image and the hologram are denoted by S and S , respectively. The effectiveness of our technique14 arises because the convergence light can be used to change the directions of the 0th-, +1st-, and –1st-order wave vectors of an object to the hologram. The original and changed wave vectors are represented by the solid black and red arrows in Figure 4(a), respectively. In other words, the object light is equally distributed on the hologram. For comparison, we illustrate the equivalent situation for a Fourier hologram in Figure 4(b). In this case, if f of the convergence light is equal to z , the 0th-order light of the object is strongly concentrated on a small area of the hologram (as indicated by the blue dashed arrows). This is a well-known problem with Fourier holograms. In addition, a high dynamic range of the hologram arises from this concentration. The effective utilization of the dynamic range is particularly important for the amplitude hologram because the amplitude of spatial light modulators (SLMs) only has an 8bit dynamic range. In contrast, with our proposed method, the concentration is dispersed over the entire hologram and our average dynamic range is lower by a factor of 5–10 for the situation illustrated in Figure 4(b). This is therefore a favorable feature for use in low-dynamic range SLMs. Figure 4. Intuitive illustration of the effectiveness of convergence light for (a) the proposed phase-free method and (b) a Fourier hologram. Unlike with other projection methods, holographic projection does not intrinsically require any lenses (e.g., a zoom lens). Indeed, the lensless zoomable holographic system—see Figure 5(a)—is extremely simple because it requires only an SLM and light source, and it is therefore a promising technique for use in ultrasmall projectors. Furthermore, our proposed methodology is applicable to lensless zoomable holographic projection.3, 15,16 To demonstrate this application of our approach, we used an amplitude-modulated liquid crystal display (L3C07U from EPSON) that had a resolution of 1920×1080 pixels and a pixel pitch of 8.5μm. We also used a 120mW semiconductor laser, at a wavelength of 532nm, as the light source. To generate the amplitude holograms, we took the real part of the complex amplitude on the hologram. The optical reconstructions from the holograms we thus obtained, through the random phase and proposed random phase-free methods, are shown in Figure 5(b). Our use of the scaled diffraction17 means that both reconstructions can be zoomed without using the zoom lens. The optical reconstruction obtained through our proposed method has a higher quality (lower speckle noise and a sharper image) than that obtained via the random phase method. Our proposed method is also effective for color image reconstructions.13 Lensless zoomable color reconstructions that we produced using the random phase method and the random phase-free method are shown in Figure 6, where the latter is clearly superior. Figure 5. (a) Schematic diagram of lensless zoomable holographic projection. SLM: Spatial light modulator. (b) Lensless zoomable optical reconstructions from holograms obtained via the random phase and proposed phase-free methods. Magnification (M) values for each set of images are given. Figure 6. Lensless zoomable color reconstructions obtained using the random phase and proposed phase-free methods. In summary, we have introduced a simple and computationally inexpensive method that can be used to increase the spatial resolution and reduce the speckle noise of computer-generated holograms. In our random phase-free approach, we multiply the object light with the virtual convergence light. We have also demonstrated the suitability and effectiveness of the technique for a number of applications. In our future work we will investigate the feasibility of our proposed method for holographic 3D display, encryption, and multiple-spot generation. This work is partially supported by Japan Society for the Promotion of Science KAKENHI grants (16K00151 and 25330125). All of the results presented here were obtained using our numerical library for wave optics.18 Chiba University Tomoyoshi Shimobaba received his PhD from Chiba University in 2002 and is now an associate professor. His research interests are computer holography and its applications. He is a member of SPIE, the Optical Society (OSA), the Optical Society of Japan (OSJ), the Institute of Image Information and Television Engineers (ITE), and the Institute of Electronics, Information, and Communication Engineers (IEICE). Takashi Kakue is an assistant professor. He received his PhD from Kyoto Institute of Technology, Japan, in 2012. His research interests are holography, digital holography, computer holography, holographic interferometry, 3D imaging, high-speed imaging, and ultrafast optics. He is a member of OSA, IEEE, SPIE, OSJ, the Japan Society of Applied Physics, the Information Processing Society of Japan (IPSJ), the Laser Society of Japan, and ITE. Tomoyoshi Ito is a professor. He received his PhD from the University of Tokyo, Japan, in 1994. His research interests are high-performance computing and its applications, such as electronic holography for 3D TV. He is a member of the Association for Computing Machinery, OSA, ITE, IEICE, IPSJ, and the Astronomical Society of Japan. 7. R. W. Gerchberg, W. O. Saxton, A practical algorithm for the determination of phase from image and diffraction plane pictures, Optik 35, p. 237-246, 1972. 10. T. Shimobaba, T. Kakue, Y. Endo, R. Hirayama, D. Hiyama, S. Hasegawa, Y. Nagahama, et al., Improvement of the image quality of random phase-free holography using an iterative method, Opt. Commun. 355, p. 596-601, 2015. 13. T. Shimobaba, M. Makowski, Y. Nagahama, Y. Endo, R. Hirayama, D. Hiyama, S. Hasegawa, et al., Color computer-generated hologram generation using the random phase-free method and color space conversion, Appl. Opt. 55, p. 4159-4165, 2016. 16. I. Ducin, T. Shimobaba, M. Makowski, K. Kakarenko, A. Kowalczyk, J. Suszek, M. Bieda, A. Kolodziejczyk, M. Sypek, Holographic projection of images with step-less zoom and noise suppression by pixel separation, Opt. Commun. 340, p. 131-135, 2015.

News Article | October 26, 2016

A new concept of combined disaster mitigation and sustainable engineering is illustrated through a number of proposed tsunami and river flooding protection schemes. As serious disasters have occurred around the world in recent years, a large number of people have been lost despite rapid advancements in science and technology. Furthermore, my personal experience of the 11 March 2011 Japanese earthquake and tsunami prompted me to think about realizing disaster mitigation strategies through novel ideas and methodologies. To that end, I have brought together a number of enthusiastic people from various fields to build a platform and create new technologies and products for disaster mitigation. In addition to disaster mitigation, our new concept—‘disaster mitigation and sustainable engineering’—is sustainable, and has high reliability and low costs. Moreover, this platform is made possible because of the innovative field of smart structures and materials.1, 2 Several projects have already been undertaken to try and meet this challenge of disaster mitigation, some of which have been commercialized. These smart products include the Hitachi Zosen Corporation's neo RiSe® (no energy, no operation, rising seawall) land-mounted movable flap-gate-type seawall, which can be autonomously deployed using the force of tsunamis.3 The MOSE (experimental electromechanical module) project,4 Aqua Dam,5 and Water-Gate6 flood protection schemes have also been developed. In addition, Takenaka Corporation has proposed the so-called breakwater and breakwater group approach.7 The basis of our disaster mitigation and sustainable engineering concept is illustrated in Figure 1. Although serious disasters may not occur for long periods of time, the structures necessary for disaster mitigation require vast construction and maintenance costs. It is thus beneficial to use these same structures daily to produce something useful, such as energy. The energy that is generated can then be used for the monitoring, maintenance, corrosion suppression, and repair of these structures, as well as for many other purposes (e.g., lighting, charging, and drones). As the mitigation structures need to be available continuously (i.e., mostly for periods without disasters), their compactness is useful from an aesthetic point of view and their daily usage is indispensable for commercialization. In addition to the examples shown in Figure 1, many other ideas (e.g., ‘smart shelter’ and ‘smart furniture’) have been proposed to protect valuable items from damage during disaster situations (see Figure 2). In this work,8 we introduce several additional examples to demonstrate our disaster mitigation and sustainable engineering concept more comprehensively. Figure 1. Typical examples that illustrate the concept of disaster mitigation and sustainable engineering. Figure 2. Examples of proposed disaster mitigation and sustainable engineering projects. (a) A multi-layered flexible and deployable structural material (see Figure  Examples of proposed disaster mitigation and sustainable engineering projects. (a) A multi-layered flexible and deployable structural material (see Figure 3 ) for protection against tsunamis. (b) A honeycomb-based smart structure (see Figure 5 ) for river flooding protection. (c) An artificial forest for mitigation against high waves and tsunamis. Examples of ‘smart shelter’ and ‘smart furniture’ for the protection of valuable items are also illustrated in the bottom right. For protection against tsunamis, rigid and fragile structures are unsuitable. Strong, light, and flexible structures are preferred instead. We have therefore been developing a multilayered flexible and deployable structural material system—see Figure 2(a) and Figure 3—which can be used to diminish the force of a tsunami. This system can also be used to dissipate the tsunami's energy by separating water flows and letting them conflict with each other. Figure 3. Top: Images of a multi-layered and deployable structural material system that can be used to diminish the force of a tsunami. Bottom: Computational fluid dynamics flow simulations are used to quantitatively evaluate the energy absorption of this newly designed tsunami barrier. Our second example—artificial and multifunctional forests—is illustrated in Figure 2(c). Natural forests present several problems, including low fractions of trees, low visibility of ocean waves, low strength, and long periods of growth. With our proposed artificial forests, we therefore intend to have a better ability to mitigate against high waves and tsunamis. We can achieve an ideal state for this forest by optimizing various parameters (e.g., configuration, density, and material). So far, we have used a water channel set up (see Figure 4) to examine a couple of these experimental parameters. We are also considering multifunctional designs for the artificial forests. Figure 4. Side view of water flow experiment (including aluminum cylinders) used to characterize the proposed artificial forest approach to tsunami mitigation. Another of our examples—see Figure 2(b) and Figure 5—is a new smart honeycomb-based structure, which can be used to protect against flooding. We have demonstrated the possibility of automatically deploying this proposed structure in response to increased water levels. This autonomous height-controlled river or anti-flooding bank system can thus be regarded as a smart structure. We are also currently investigating the use of energy-harvesting materials and systems to improve the autonomy of this structure and to fully realize the concept. Figure 5. Illustration of the honeycomb-based deployable smart structure for flood protection. All dimensions are given in millimeters. POM: Polyoxymethylene. PVC: Polyvinyl chloride. Several different aspects of ongoing research are also being conducted with my various collaborators. For example, we are pursuing applications of piezoelectric polymers for electrical power generation with the use of ocean waves.9 In addition, we are investigating the dynamic deployment of smart inflatable tsunami bags for tsunami mitigation purposes.10 Novel underwater inflatable structures for smart coastal disaster mitigation are also being studied.11 In other work, we are examining structural health monitoring of pipelines for environment pollution mitigation.12 The Italian Space Agency's geodetic satellite LARES (Laser Relativity Satellite) is also being used to study global climate change.13 Finally, we are investigating smart disaster mitigation strategies in both Italy14 and in Thailand.15 In summary, we have developed a new concept of disaster mitigation and sustainable engineering that is based on smart structures and materials. To illustrate this approach, we have discussed three potential examples of projects for protection against tsunamis and river flooding. As part of a large international collaboration we are also continuing to conduct research in a number of different areas related to disaster mitigation and sustainable engineering. As part of our future work, I will be working with international executive members of the collaboration to establish a research committee. This committee will also include several researchers from Chiba University and members of the Japan Society of Mechanical Engineers. Most recently,16 we have started to explore other innovative ideas and challenges (e.g., offshore megafloating structures with energy harvesting and dissipation functions). We welcome requests for information and collaboration possibilities. The work shown in Figure 3 was performed in collaboration with M. Kubo, Y. Maruyama, and G. Tanaka from Chiba University, Japan. Department of Mechanical Engineering Chiba University Hiroshi Asanuma obtained his Dr. Engineering degree from the University of Tokyo, Japan. He then worked as a research associate at the Institute of Industrial Science, University of Tokyo, and as an assistant professor and an associate professor at Chiba University. He has also worked as a visiting professor at the University of Wollongong, Australia, and Sapienza University of Rome, Italy. Since then he has been a professor at Chiba University. He has also served as the chair of the Japan Society of Mechanical Engineers (JSME) Materials and Processing (M&P) division, and he is the chair of the Active Material System technical section of the JSME M&P division. In addition, he is a fellow of JSME and the Institute of Physics. He has received several awards, including the Excellent Achievement Medal, International Medal, and Excellent Performance Medal from the JSME M&P division. 1. H. Asanuma, J. Su, M. Shahinpoor, F. Felli, A. Paolozzi, M. Nejhad, L. Hihara, et al., Development of disaster mitigation and sustainable engineering based on smart materials and structures, World Eng. Conf. Conv., p. 20344, 2015. 4. Information regarding the MOSE project in Venice, Italy. Accessed 25 April 2016. 9. J. Su, H. Asanuma, Applications of piezoelectric polymers in electrical power generation using ocean waves. Presented at SPIE Smart Structures/NDE 2015. 10. M. Shahinpoor, H. Asanuma, Dynamic deployment of smart inflatable tsunami airbags (TABs) for tsunami disaster mitigation, Am. Soc. Mech. Eng. Proc. Conf. Smart Mater. Adapt. Struct. Intell. Syst. 2, p. SMASIS2015-8904, 2015. doi:10.1115/SMASIS2015-8904 11. K. Adachi, H. Asanuma, A novel underwater inflatable structure for smart coastal disaster mitigation, Am. Soc. Mech. Eng. Proc. Conf. Smart Mater. Adapt. Struct. Intell. Syst., p. 9082, 2015. 12. F. Felli, A. Paolozzi, C. Vendittozzi, C. Paris, H. Asanuma, G. De Canio, M. Mongelli, A. Colucci, Structural health monitoring of pipelines for environment pollution mitigation, Am. Soc. Mech. Eng. Proc. Conf. Smart Mater. Adapt. Struct. Intell. Syst. 2, p. SMASIS2015-8922, 2015. doi:10.1115/SMASIS2015-8922 13. G. Sindoni, C. Paris, C. Vendittozzi, E. C. Pavlis, I. Ciufolini, A. Paolozzi, The contribution of LARES to global climate change studies with geodetic satellites, Am. Soc. Mech. Eng. Proc. Conf. Smart Mater. Adapt. Struct. Intell. Syst. 2, p. SMASIS2015-8924, 2015. doi:10.1115/SMASIS2015-8924 14. F. Felli, A. Paolozzi, C. Vendittozzi, C. Paris, Smart disaster mitigation in Italy: a brief overview on the state of the art, Am. Soc. Mech. Eng. Proc. Conf. Smart Mater. Adapt. Struct. Intell. Syst. 2, p. SMASIS2014-7631, 2014. doi:10.1115/SMASIS2014-7631

News Article | February 15, 2017

How do plants give up photosynthesis and become parasites? A research team in Japan are using comprehensive analysis of gene expression in albino and green orchids to investigate the evolution of parasitic plants. The research was carried out by Project Associate Professor SUETSUGU Kenji (Kobe University Graduate School of Science), Associate Professor KAMINAKA Hironori and Research Fellow MIURA Chihiro (Tottori University Faculty of Agriculture), Associate Professor YAMATO Masahide (Chiba University Faculty of Education), and Special Associate Professor SHIGENOBU Shuji (National Institute for Basic Biology). Spontaneous mutation resulting in loss of chlorophyll is a phenomenon seen among many plant species. In normal plant species, albino mutations that lack chlorophyll wither after using up the nutrients stored in their seeds, but albinos of semi-parasitic species can continue to grow and even produce flowers. These albino plants, lacking chlorophyll, become totally dependent on fungi for their survival. Plants that have abandoned photosynthesis and feed off the roots of mushrooms and other fungi are known as mycoheterotrophs. Most mycoheterotrophs are a long way genetically from even their closest autotrophic plants. In addition to the evolutionary adaptation that enabled their parasitic lifestyle, they have various other mutations, making it hard to pinpoint which gene group helped them to gain their parasitic abilities (see figure 1). This study focused on the orchid species Epipactis helleborine. Although this species has developed green leaves and at first glance appears to be able to survive from photosynthesis alone, it is semi-dependent on fungi for carbon. Semi-mycoheterotrophic species such as E. helleborine occasionally undergo spontaneous mutations into albino varieties, totally losing their chlorophyll (see figure 2). The green individuals and the albino individuals have almost identical genome sequences, making them ideal candidates for genetic analysis of mycoheterotrophy (see figure 3). Because albino individuals lack chlorophyll, they are thought to depend more on their parasitic abilities than green individuals. This study investigated the possibility that the genes expressing more in albino varieties are related to mycoheterotrophy (parasitism of fungi). The research team focused on these highly-expressing gene groups. The group carried out transcriptome analysis using RNA extracted from the roots of 3 green individuals and 3 albino individuals of the E. helleborine. The results showed that the gene group linked to mycorrhizal symbiosis in arbuscular mycorrhizal plants and autotrophic orchids is also highly expressed in albino individuals of E. helleborine. Additionally, the expression patterns from multiple genetic groups related to plant hormone biosynthesis showed similarities between albino individuals and plants associated with arbuscular mycorrhizal fungi. These results suggest that mycoheterotrophs may incorporate fungi by using a similar mechanism to those found in other types of mycorrhizal symbiosis. Until now, botanists believed that mycorrhizal symbiosis in mycoheterotrophs used a different mechanism from other types of mycorrhizal symbiosis because of the dramatic partner shift in mycorrhizal fungi. However, this research suggests they may have more mechanisms in common than previously imagined. The findings were published on January 19 in the online edition of Molecular Ecology. Species which have lost the ability to photosynthesize and take their nutrients from fungi. Approximately 50 of these species have been reported in Japan, including families such as Ericaceae, Polygalaceae, Gentianaceae, Burmanniaceae, Corsiaceae, Thismiaceae, Orchidaceae, Petrosaviaceae and Triuridaceae.

Neya S.,Chiba University | Yonetani T.,University of Pennsylvania | Kawaguchi A.T.,Tokai University
Artificial Organs | Year: 2014

The structure and reactivity of cobalt-replaced myoglobin (Mb) were investigated to explore its possible application as an artificial oxygen carrier. Ligand binding analysis with relaxation kinetics revealed that various ligands bind to Co(III) Mb, contrary to the earlier thoughts. The equilibration process, however, was so slow that it proceeded over 90min. These characteristic profiles of oxidized Co(III) Mb were ascribed to the electronic structure of Co(III) ion which is one electron larger than Fe(III) ion. The oxygen affinity of reduced Co(II) Mb was much smaller than that of Fe(II) Mb indicating that Co(II) Mb has excellent oxygen transport ability. The latter observation, together with the lack of carbon monoxide binding in Co(II) Mb, suggests utility of Co(II) Mb as Mb-based oxygen carriers. The present results on cobalt-substituted Mb are useful in designing myoglobin-based oxygen carriers. © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Ohara S.,Tohoku Rosai Hospital | Kawano T.,Tokyo Medical and Dental University | Kusano M.,Gunma University | Kouzu T.,Chiba University
Journal of Gastroenterology | Year: 2011

Background: The present survey aimed to clarify the prevalence of gastroesophageal reflux disease (GERD) and functional dyspepsia (FD) in patients presenting with epigastric symptoms in Japan based on the Montreal definition and the Rome III criteria, respectively, and to determine the degree of overlap between the two disease entities and the validity of using these Western-developed diagnostic criteria in Japan. Methods: Patients presenting with epigastric symptoms for whom the first upper gastrointestinal endoscopy was scheduled from April through August 2007 at 55 institutions were asked to complete a questionnaire to ascertain the type, frequency, and severity of epigastric symptoms. The prevalence of esophageal mucosal damage was also determined from endoscopic findings. Results: A total of 1,076 patients were included in the analysis population. There was a high degree of coincidence for all symptoms, with the mean number of symptoms per patient of 2.8. With strict application of the Montreal and Rome III definitions, symptomatic GERD accounted for 15.6% (168 patients), whereas FD accounted for 10.3% (111 patients), and the overlap between GERD and FD symptoms was less than 10%. However, when frequency and severity alone were considered in more broadly defined criteria, the overlap between GERD and FD symptoms was 30-40%. Conclusion: A highly specific disease classification is possible when the Montreal definition and the Rome III criteria are strictly applied. On the other hand, the present survey highlighted a problem with the criteria whereby a definitive diagnosis could not be made in a substantial number of patients. This problem will require further research. © 2011 Springer.

Bikbova G.,Chiba University | Bikbov M.,Ufa Eye Research Institute
Acta Ophthalmologica | Year: 2014

Purpose: To evaluate the effectiveness of transepithelial cornea impregnation with riboflavin 0.1% by iontophoresis for collagen cross-linking. Material and methods: Transepithelial collagen cross-linking by iontophoresis of riboflavin was performed in a series of 22 eyes of 19 patients with progressive keratoconus I-II of Amsler classification. The riboflavin solution was administered by iontophoresis for 10 min in total, after which standard surface UVA irradiation (370 nm, 3 mW/cm2) was performed at a 5-cm distance for 30 min. Results: The riboflavin/UVA treatment resulted in a decrease in the average keratometry level from 46.47 ± 1.03 to 44.12 ± 1.12 D 1 year after the procedure. Corneal astigmatism decreased from 3.44 ± 0.48 to 2.95 ± 0.23 D. Uncorrected distance visual acuity improved from 0.61 ± 0.44 up to 0.48 ± 0.41 (LogMAR). Preoperative and postoperative endothelial cell density remained unchanged at 2765 ± 21.15 cells/mm 2. Conclusion: Transepithelial collagen cross-linking by iontophoresis might become an effective method for riboflavin impregnation of the corneal stroma reducing the duration of the procedure and being more comfortable for the patients. Further long-term studies are necessary to complete the evaluation of the efficacy and risk spectrum of the modified cross-linking technique. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Hamad A.M.,Menoufia University | Tsumura N.,Chiba University
Optical Review | Year: 2012

This paper proposes a robust method to detect and extract silhouettes of foreground objects from a video sequence of a static camera based on the improved background subtraction technique. The proposed method analyses statistically the pixel history as time series observations. The proposed method presents a robust technique to detect motions based on kernel density estimation. Two consecutive stages of the k-means clustering algorithm are utilized to identify the most reliable background regions and decrease the detection of false positives. Pixel and object based updating mechanism for the background model is presented to cope with challenges like gradual and sudden illumination changes, ghost appearance, non-stationary background objects, and moving objects that remain stable for more than the half of the training period. Experimental results show the efficiency and the robustness of the proposed method to detect and extract the silhouettes of moving objects in outdoor and indoor environments compared with conventional methods. © 2012 The Optical Society of Japan.

Schmaus S.,Karlsruhe Institute of Technology | Bagrets A.,Karlsruhe Institute of Technology | Nahas Y.,Karlsruhe Institute of Technology | Yamada T.K.,Karlsruhe Institute of Technology | And 6 more authors.
Nature Nanotechnology | Year: 2011

Magnetoresistance is a change in the resistance of a material system caused by an applied magnetic field. Giant magnetoresistance occurs in structures containing ferromagnetic contacts separated by a metallic non-magnetic spacer, and is now the basis of read heads for hard drives and for new forms of random access memory. Using an insulator (for example, a molecular thin film) rather than a metal as the spacer gives rise to tunnelling magnetoresistance, which typically produces a larger change in resistance for a given magnetic field strength, but also yields higher resistances, which are a disadvantage for real device operation. Here, we demonstrate giant magnetoresistance across a single, non-magnetic hydrogen phthalocyanine molecule contacted by the ferromagnetic tip of a scanning tunnelling microscope. We measure the magnetoresistance to be 60% and the conductance to be 0.26G0, where G0 is the quantum of conductance. Theoretical analysis identifies spin-dependent hybridization of molecular and electrode orbitals as the cause of the large magnetoresistance. © 2011 Macmillan Publishers Limited. All rights reserved.

Nakada H.,Chiba University | Nakada H.,University Claude Bernard Lyon 1
Physical Review C - Nuclear Physics | Year: 2015

It was pointed out [Phys. Rev. C 91, 021302(R) (2015)PRVCAN0556-281310.1103/PhysRevC.91.021302] that the isotope shifts of the Pb nuclei, the kink at N=126 in particular, can be well described by Hartree-Fock-Bogolyubov calculations if a density-dependent LS interaction derived from the 3N interaction is incorporated. Effects of the density dependence in the LS channel on the isotope shifts are extensively investigated for the Ca, Ni, and Sn isotopes, using the semirealistic M3Y-P6 interaction and its LS modified variant M3Y-P6a, as in the Pb case. It is found that almost equal charge radii between Ca40 and Ca48 are reproduced, as well as the isotope shifts in a long chain of the Sn nuclei, owing to the density dependence in the LS channel. A kink is predicted at N=82 for the isotope shifts of the Sn nuclei, in clear contrast to the interactions without the density dependence. © 2015 American Physical Society.

Oi N.,Tokyo Women's Medical University | Ohi K.,Chiba University
International Journal of Cosmetic Science | Year: 2012

We conducted a survey to elucidate the influence with menopause symptoms and the impact of not only smoking but also using make-up among for Japanese women, included ages above and below the menopausal generation. The subjects of this study were 335 Japanese women from 35 to 59 years of age who were examined for the first time in the specialized women's outpatient clinic of our institution from July 2010 to June 2011 for 1 year period. We used the items of the Menopause-Specific Quality of Life Questionnaire. Similarly, we analysed the scores in relation to menopausal symptoms and whether the subject smoked, whether the subject used make-up depend on women (including foundation, lip rouge, brush one's eyebrows), how frequently she used make-up. The JMP version 9.0 software program was used to statistically analyse the score data. Significant associations were observed in psychosocial (P = 0.0196), tended to be more severe in women before menopause and after climacteric. Furthermore, the frequency of using make-up were negative relations with menopause symptoms (P = 0.0251) after climacteric. Smoking had made worse for physical symptoms (P < 0.001). Menopause symptoms are already experienced by younger women, especially, psychological symptoms. Also, physical conditions were influenced by smoking. Using make-up frequently was often seen after climacteric because of appearance changes by oestrogen dynamic decline. © 2012 The Authors. ICS © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Yoshimi N.,Chiba University | Yoshimi N.,Otsuka Pharmaceutical Factory Inc. | Futamura T.,Otsuka Pharmaceutical Factory Inc. | Hashimoto K.,Chiba University
European Neuropsychopharmacology | Year: 2015

Cognitive impairment, including impaired social cognition, is largely responsible for the deterioration in social life suffered by patients with psychiatric disorders, such as schizophrenia and major depressive disorder (MDD). Brexpiprazole (7-{4-[4-(1-benzothiophen-4-yl)piperazin-1-yl]butoxy}quinolin-2(1H)-one), a novel serotonin-dopamine activity modulator, was developed to offer efficacious and tolerable therapy for different psychiatric disorders, including schizophrenia and adjunctive treatment of MDD. In this study, we investigated whether brexpiprazole could improve social recognition deficits (one of social cognition deficits) in mice, after administration of the N-methyl-d-aspartate (NMDA) receptor antagonist MK-801 (dizocilpine). Dosing with dizocilpine (0.1mg/kg) induced significant impairment of social recognition in mice. Brexpiprazole (0.01, 0.03, 0.1mg/kg, p.o.) significantly ameliorated dizocilpine-induced social recognition deficits, without sedation or a reduction of exploratory behavior. In addition, brexpiprazole alone had no effect on social recognition in untreated control mice. By contrast, neither risperidone (0.03mg/kg, p.o.) nor olanzapine (0.03mg/kg, p.o.) altered dizocilpine-induced social recognition deficits. Finally, the effect of brexpiprazole on dizocilpine-induced social recognition deficits was antagonized by WAY-100,635, a selective serotonin 5-HT1A antagonist. These results suggest that brexpiprazole could improve dizocilpine-induced social recognition deficits via 5-HT1A receptor activation in mice. Therefore, brexpiprazole may confer a beneficial effect on social cognition deficits in patients with psychiatric disorders. © 2015 Elsevier B.V. and ECNP.

Arai Y.,Chiba University | Miyayama T.,Japan National Institute of Environmental Studies | Miyayama T.,Tokyo Women's Medical University | Hirano S.,Chiba University | Hirano S.,Japan National Institute of Environmental Studies
Toxicology | Year: 2015

The health effects of silver nanoparticles (AgNPs) have not been well investigated, despite AgNPs now being widely used in consumer products. We investigated the metabolic behavior and toxicity of AgNPs in comparison to silver nitrate (AgNO3) both in vivo and in vitro. AgNPs (20nm diameter) suspended in 1% albumin solution or AgNO3 solution was injected into the mouse lung. Less than 1% of the initial dose of AgNPs and more than 7% of the initial dose of AgNO3 was recovered in the liver 4h after administration, suggesting that the ionic form of silver was absorbed by the lung tissue and entered the systemic circulation more efficiently than AgNPs. The pro-inflammatory cytokine, IL-1β, and neutrophils in bronchoalveolar lavage fluid (BALF) increased following intratracheal instillation of AgNPs or AgNO3. AgNO3 recruited more neutrophils in the alveolar space than did AgNPs. In the in vitro study, AgNO3 was more cytotoxic than 20, 60, or 100nm diameter AgNPs in a mouse macrophage cell line (J774.1). To investigate the intracellular distribution of Ag in detail, J774.1 cells were exposed to AgNO3 or 20nm AgNPs and the distribution of Ag to cytosolic proteins was investigated using HPLC-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). Ag was mainly distributed to metallothioneins (MT) and to high molecular weight proteins in AgNO3- and AgNPs-exposed cells, respectively. Confocal laser microscopic examination of LysoTracker®-labeled cells indicated that AgNPs were colocalized with lysosomes in J774.1 cells. These results suggest that AgNPs were transported to lysosomes and only gradually dissolved in the macrophages, causing milder inflammatory stimulation in the mouse lung compared to AgNO3. © 2014 Elsevier Ireland Ltd.

Yamada M.,Chiba University | Utoh R.,Tokyo Women's Medical University | Ohashi K.,Tokyo Women's Medical University | Tatsumi K.,Tokyo Women's Medical University | And 3 more authors.
Biomaterials | Year: 2012

We have developed a hydrogel-based cell cultivation platform for forming 3D restiform hepatic micro-organoids consisting of primary rat hepatocytes and feeder cells (Swiss 3T3 cells). Sodium alginate solutions containing hepatocytes/3T3 cells were continuously introduced into a microfluidic channel to produce cell-incorporating anisotropic Ba-alginate hydrogel microfibers, where hepatocytes at the center were closely sandwiched by 3T3 cells. Hydrogel fiber-based cultivation under high oxygen tension enabled the formation of heterotypic micro-organoids with a length of up to 1 mm and a diameter of ~50 μm, mimicking the hepatic cord structures found in the liver, while maintaining a high hepatocyte viability (~80%) over 30 days. Long-term observation of up to 90 days revealed a significant enhancement of hepatic functions because of heterotypic and homotypic cell-cell interactions, including albumin secretion and urea synthesis as well as expression of hepatocyte-specific genes, compared with conventional monolayer culture and single cultivation in the hydrogel fibers. The encapsulated hepatic constructs were recovered as scaffold-free micro-organoids by enzymatically digesting the hydrogel matrices using alginate lyase. This technique for creating heterotypic micro-organoids with precisely ordered multiple cell types will be useful for the development of a new liver tissue engineering approach and may be applicable to the fabrication of extracorporeal bioartificial liver (BAL) devices and assessment tools for drug development and testing. © 2012 Elsevier Ltd.

Masu H.,Chiba University | Tominaga M.,Tokushima Bunri University | Azumaya I.,Tokushima Bunri University
Crystal Growth and Design | Year: 2013

Eight cocrystals were formed from three adamantane-based bisphenols with structurally analogous skeletons and three bispyridines. Various 1D chains were constructed through intermolecular OH/N hydrogen bonds. Two crystals containing nonsubstituted bisphenols showed the formation of 1D zigzag chains, which were generated from two bisphenols and two bispyridines in one pitch of the 1D chain. Three crystals including chlorine-substituted bisphenols indicated the generation of 1D zigzag chains, and the pitches of these chains were longer than that of 1D chains composed of nonsubstituted bisphenols. Three crystals containing bromine-substituted bisphenols exhibited different shapes of 1D chains from other crystals, which were consisted of one bisphenol and one bispyridine in one pitch. These 1D chains assembled via intermolecular CH/O and/or CH/π interactions. The halogen substituents on the adamantane-based bisphenols influence on not only the shapes of 1D chains, but also 2D and 3D structures mainly due to steric hindrances. © 2013 American Chemical Society.

Ohgi Y.,Chiba University | Ohgi Y.,Otsuka Pharmaceutical Factory Inc. | Futamura T.,Otsuka Pharmaceutical Factory Inc. | Kikuchi T.,Otsuka Pharmaceutical Factory Inc. | Hashimoto K.,Chiba University
Pharmacology Biochemistry and Behavior | Year: 2013

Accumulating evidence suggests that inflammation may play a role in the pathophysiology of major depressive disorder (MDD). Antidepressants, including selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs), possess anti-inflammatory effects in vitro. Here, we examined the effects of SSRIs and SNRIs on lipopolysaccharide (LPS)-induced inflammation and depressive-like behavior in male mice. A single administration of LPS (0.5 mg/kg, i.p.) increased serum levels of the pro-inflammatory cytokine, tumor necrosis factor-α (TNFα) and the anti-inflammatory cytokine, interleukin-10 (IL-10) in mice. Pretreatment with SSRIs (fluoxetine and paroxetine), SNRIs (venlafaxine and duloxetine), or 5-hydroxytryptophan (5-HTP), a precursor of serotonin, attenuated LPS-induced increases in TNFα, whereas it increased serum levels of IL-10, in mice treated with LPS. In the tail suspension test (TST), LPS increased the immobility time without affecting spontaneous locomotor activity, suggesting that LPS induced depressive-like behavior in mice. Treatment with fluoxetine (30 mg/kg) or paroxetine (10 mg/kg) significantly shortened LPS-induced increases of immobility time. These results suggested that antidepressants exert anti-inflammatory effects in vivo, and that the serotonergic system may partially mediate these effects. In addition, the anti-inflammatory effects of antidepressants may help alleviate the symptoms of LPS-induced depression in mice. © 2012 Elsevier Inc.

Weber S.M.,University of Wisconsin - Madison | Ribero D.,Mauriziano Umberto i Hospital | O'Reilly E.M.,Sloan Kettering Cancer Center | Kokudo N.,University of Tokyo | And 2 more authors.
HPB | Year: 2015

An American Hepato-Pancreato-Biliary Association (AHPBA)-sponsored consensus meeting of expert panellists met on 15 January 2014 to review current evidence on the management of intrahepatic cholangiocarcinoma (ICC) in order to establish practice guidelines and to agree on consensus statements. The treatment of ICC requires a coordinated, multidisciplinary approach to optimize survival. Biopsy is not necessary if the surgeon suspects ICC and is planning curative resection, although biopsy should be obtained before systemic or locoregional therapies are initiated. Assessment of resectability is best accomplished using cross-sectional imaging [computed tomography (CT) or magnetic resonance imaging (MRI)], but the role of positron emission tomography (PET) is unclear. Resectability in ICC is defined by the ability to completely remove the disease while leaving an adequate liver remnant. Extrahepatic disease, multiple bilobar or multicentric tumours, and lymph node metastases beyond the primary echelon are contraindications to resection. Regional lymphadenectomy should be considered a standard part of surgical therapy. In patients with high-risk features, the routine use of diagnostic laparoscopy is recommended. The preoperative diagnosis of combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC) by imaging studies is extremely difficult. Surgical resection remains the mainstay of treatment, but survival is worse than in HCC alone. There are no adequately powered, randomized Phase III trials that can provide definitive recommendations for adjuvant therapy for ICC. Patients with high-risk features (lymphovascular invasion, multicentricity or satellitosis, large tumours) should be encouraged to enrol in clinical trials and to consider adjuvant therapy. Cisplatin plus gemcitabine represents the standard-of-care, front-line systemic therapy for metastatic ICC. Genomic analyses of biliary cancers support the development of targeted therapeutic interventions. © 2015 International Hepato-Pancreato-Biliary Association.

Walley K.R.,University of British Columbia | Thain K.R.,University of British Columbia | Russell J.A.,University of British Columbia | Reilly M.P.,University of Pennsylvania | And 8 more authors.
Science Translational Medicine | Year: 2014

A decrease in the activity of proprotein convertase subtilisin/kexin type 9 (PCSK9) increases the amount of lowdensity lipoprotein (LDL) receptors on liver cells and, therefore, LDL clearance. The clearance of lipids from pathogens is related to endogenous lipid clearance; thus, PCSK9 may also regulate removal of pathogen lipids such as lipopolysaccharide (LPS). Compared to controls, Pcsk9 knockout mice displayed decreases in inflammatory cytokine production and in other physiological responses to LPS. In human liver cells, PCSK9 inhibited LPS uptake, a necessary step in systemic clearance and detoxification. Pharmacological inhibition of PCSK9 improved survival and inflammation in murine polymicrobial peritonitis. Human PCSK9 loss-of-function genetic variants were associated with improved survival in septic shock patients and a decrease in inflammatory cytokine response both in septic shock patients and in healthy volunteers after LPS administration. The PCSK9 effect was abrogated in LDL receptor (LDLR) knockout mice and in humans who are homozygous for an LDLR variant that is resistant to PCSK9. Together, our results show that reduced PCSK9 function is associated with increased pathogen lipid clearance via the LDLR, a decreased inflammatory response, and improved septic shock outcome.

Tanaka Y.,Stevens Institute of Technology | Sakamoto Y.,Stevens Institute of Technology | Matsuka T.,Chiba University
Proceedings of the Annual Hawaii International Conference on System Sciences | Year: 2013

Critical thinking is an important part of media literacy. It allows people to find facts among rumors and to inactivate false information. Such abilities are essential when social media is flooded with rumors during disaster response. We envision a social-technological system in which critical thinking is crowd-sourced: Individuals benefit from others' criticisms of false information, and the system inactivates the spread of false information. To test the plausibility of this system, we examined the effect of exposure to criticisms on people's decision to spread rumors in social media. When people were exposed to criticisms before rumors, the proportion of responses aimed at stopping the spread of rumors was significantly larger than when people were exposed to rumors before criticisms. We identified some psychological factors that could explain this effect. Based on our results, we discuss practical implications for developing a social-technological system that harnesses the critical thinking of crowds. © 2012 IEEE.

Albayrak Y.,Namik Kemal University | Hashimoto K.,Chiba University
Psychiatry Investigation | Year: 2013

Fluvoxamine is a selective serotonin reuptake inhibitor that is approved for psychiatric disorders such as major depressive episodes and obsessive-compulsive disorder. Beside inhibition of serotonin reuptake, fluvoxamine is also a potent agonist of endoplasmic reticulum (ER) protein sigma-1 receptors, which play a role in the pathophysiology of a number of psychiatric and neurodegenerative disorders. This report presents beneficial efects of sigma-1 agonist fuvoxamine on hyperkinetic movement disorders such as tardive dyskinesia and tardive akathisia. Fluvoxamine might be a novel treatmet approach in the treatment of hyperkinetic movement disorders. © 2013 Korean Neuropsychiatric Association.

Imamoto T.,Nippon Chemical Industrial Co. | Imamoto T.,Chiba University | Tamura K.,Nippon Chemical Industrial Co. | Zhang Z.,Nippon Chemical Industrial Co. | And 5 more authors.
Journal of the American Chemical Society | Year: 2012

Both enantiomers of 2,3-bis(tert-butylmethylphosphino)quinoxaline (QuinoxP*), 1,2-bis(tert-butylmethylphosphino)benzene (BenzP*), and 1,2-bis(tert-butylmethylphosphino)-4,5-(methylenedioxy)benzene (DioxyBenzP*) were prepared in short steps from enantiopure (S)- and (R)-tert-butylmethylphosphine-boranes as the key intermediates. All of these ligands were crystalline solids and were not readily oxidized on exposure to air. Their rhodium complexes exhibited excellent enantioselectivities and high catalytic activities in the asymmetric hydrogenation of functionalized alkenes, such as dehydroamino acid derivatives and enamides. The practical utility of these catalysts was demonstrated by the efficient preparation of several chiral pharmaceutical ingredients having an amino acid or a secondary amine component. A rhodium complex of the structurally simple ligand BenzP* was used for the mechanistic study of asymmetric hydrogenation. Low-temperature NMR studies together with DFT calculations using methyl α-acetamidocinnamate as the standard model substrate revealed new aspects of the reaction pathways and the enantioselection mechanism. © 2011 American Chemical Society.

Yamada A.,Chiba University | Seki K.,Chiba University | Eder R.,Karlsruhe Institute of Technology | Ohta Y.,Chiba University
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

Mott transition and ferrimagnetism are studied in the Hubbard model on the anisotropic kagome lattice using the variational cluster approximation and the phase diagram at zero temperature and half filling is analyzed. The ferrimagnetic phase rapidly grows as the geometric frustration is relaxed, and the Mott-insulator phase disappears in the moderately frustrated region showing that the ferrimagnetic fluctuations stemming from the relaxation of the geometric frustration are enhanced by the electron correlations. In the metallic phase, heavy-fermion behavior is observed and the mass-enhancement factor is computed. The enhancement of effective spatial anisotropy by the electron correlations is also confirmed in the moderately frustrated region and its effect on heavy-fermion behavior is examined. © 2011 American Physical Society.

Seki K.,Chiba University | Eder R.,Karlsruhe Institute of Technology | Ohta Y.,Chiba University
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

We study the spontaneous symmetry breaking of the excitonic insulator state induced by the Coulomb interaction U in the two-dimensional extended Falicov-Kimball model. Using the variational cluster approximation (VCA) and Hartree-Fock approximation (HFA), we evaluate the order parameter, single-particle excitation gap, momentum distribution functions, coherence length of excitons, and single-particle and anomalous excitation spectra as functions of U at zero temperature. We find that in the weak-to-intermediate coupling regime, the Fermi surface plays an essential role and calculated results can be understood in close correspondence with the BCS theory, whereas in the strong-coupling regime, the Fermi surface plays no role and results are consistent with the picture of a Bose-Einstein condensate (BEC). Moreover, we find that HFA works well in both the weak- and strong-coupling regimes, and that the difference between the results of VCA and HFA mostly appears in the intermediate-coupling regime. The reason for this is discussed from a viewpoint of the self-energy. We thereby clarify the excitonic insulator state that typifies either a BCS condensate of electron-hole pairs (weak-coupling regime) or a BEC of preformed excitons (strong-coupling regime). © 2011 American Physical Society.

Bagrets A.,Karlsruhe Institute of Technology | Schmaus S.,Karlsruhe Institute of Technology | Schmaus S.,Max Planck Institute for Solid State Research | Jaafar A.,CNRS Institute of Genetics and of Molecular and Cellular Biology | And 6 more authors.
Nano Letters | Year: 2012

The magnetoresistance of a hydrogen-phthalocyanine molecule placed on an antiferromagnetic Mn(001) surface and contacted by a ferromagnetic Fe electrode is investigated using density functional theory based transport calculations and low-temperature scanning tunneling microscopy. A large and negative magnetoresistance ratio of ∼50% is observed in combination with a high conductance. The effect originates from a lowest unoccupied molecular orbital (LUMO) doublet placed almost in resonance with the Fermi energy. As a consequence, irrespective of the mutual alignment of magnetizations, electron transport is always dominated by resonant transmission of Mn-majority charge carries going through LUMO levels. © 2012 American Chemical Society.

Bussolotti F.,Japan Advanced Institute of Science and Technology | Bussolotti F.,Chiba University | Friedlein R.,Japan Advanced Institute of Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

The electronic structure of an ordered anthracene monolayer prepared at 293 K on Cu(110) has been investigated using angle-resolved ultraviolet photoelectron spectroscopy (ARUPS). Spectral features observed in the binding energy region of 2-4 eV are assigned to interfacial states formed by hybridization with Cu (3d) orbitals. In the vicinity of the Fermi level, a charge-transfer state involving the lowest unoccupied molecular and Cu (4s) orbitals is formed and most likely supported by a non-negligible hybridization with 3d orbitals. The comparison to pentacene on the same surface reveals a clear relation between the strength of hybridization and the energetic separation between the Cu (3d) band and the original molecular levels. © 2010 The American Physical Society.

Ohgi Y.,Chiba University | Ohgi Y.,Otsuka Pharmaceutical Factory Inc. | Futamura T.,Otsuka Pharmaceutical Factory Inc. | Hashimoto K.,Chiba University
Current Molecular Medicine | Year: 2015

Glutamate, a major excitatory neurotransmitter, plays important roles in synaptic plasticity, such as long-term potentiation (LTP) and new synapse formation. Growing evidence suggests that glutamate signaling is involved in the neurobiology of psychiatric disorders, including schizophrenia, major depressive disorder (MDD) and bipolar disorder (BP). Postmortem brain studies demonstrated altered spine density in brains from patients with these psychiatric disorders, indicating that remodeled neuronal circuits may contribute to the pathobiology of these psychiatric diseases. Drugs targeting the glutamate system have typically attracted attention as they show efficacy in animal studies and potential therapeutic effects in the clinical setting. In particular, the Nmethyl-D-aspartate (NMDA) receptor antagonist, ketamine exerts a rapid and robust antidepressant effect in treatment-resistant patients with MDD and BP, whereas conventional antidepressants require several weeks for therapeutic onset. Animal studies showed that ketamine induced rapid synaptogenesis, suggestive of synaptic plasticity via NMDA receptor signaling being an essential event in the treatment of depression. Therefore, drugs modulating glutamate signaling could also be potential therapeutic drugs for psychiatric disorders. First, we summarize the role of glutamate signaling on dendritic spine formation, maintenance and remodeling. Then, we discuss the abnormalities identified in dendritic spine and glutamate signaling from postmortem brain studies and animal models of psychiatric disorders. Finally, we review the potential benefits of drugs acting on the NMDA receptor in clinical and animal models of psychiatric disorders. © 2015 Bentham Science Publishers.

Matsui A.,Chiba University | Kamada Y.,Japan National Institute for Basic Biology | Matsuura A.,Chiba University
PLoS Genetics | Year: 2013

The coordination of subcellular processes during adaptation to environmental change is a key feature of biological systems. Starvation of essential nutrients slows cell cycling and ultimately causes G1 arrest, and nitrogen starvation delays G2/M progression. Here, we show that budding yeast cells can be efficiently returned to the G1 phase under starvation conditions in an autophagy-dependent manner. Starvation attenuates TORC1 activity, causing a G2/M delay in a Swe1-dependent checkpoint mechanism, and starvation-induced autophagy assists in the recovery from a G2/M delay by supplying amino acids required for cell growth. Persistent delay of the cell cycle by a deficiency in autophagy causes aberrant nuclear division without sufficient cell growth, leading to an increased frequency in aneuploidy after refeeding the nitrogen source. Our data establish the role of autophagy in genome stability through modulation of cell division under conditions that repress cell growth. © 2013 Matsui et al.

Chiba University and Advanced Healthcare Co. | Date: 2013-08-23

Problem: To provide a trocar equipped with a retractable camera, with which the security is enhanced as compared with the related art. Means for Solution: An opening portion 13 is provided at a position of a pipe portion 11. The position of opening portion 13 is reliably within the body of the patient. A shaft 14 is arranged along the interior of the trocar, along an edge of the opening portion 13. Several bearings 15 are fixed to the inter wall of the pipe portion 11, with the shaft 14 being rotatably mounted in the bearings 15. The end portion of the shaft 14 extends to the exterior of the trocar, outside the body of the patient. A selection lever 16 is provided at the outer end portion of the shaft 14. The selection lever 16 can be changed over between a stored position and a deployed position, and can be fixed in each of these positions. A camera 17 is rigidly and integrally attached to the shaft 14 at a position that corresponds to the opening portion 13. A cable 18 is connected to the camera 17, extends through the interior of the trocar 1, and is connected to an external image processing device 6.

Chiba University and Advanced Healthcare Co. | Date: 2013-08-23

Problem To provide a surgery assistance system that performs measurement of shapes within the abdominal cavity at high accuracy in three dimensions, and a trocar for use in such a surgery assistance system. Means for Solution A surgery assistance system 101 includes forceps trocars 1a and 1b having retractable cameras 17a and 17b and marks 19a and 19b, a laparoscope trocar 3, forceps 4a and 4b, a laparoscope 5 having a mark 19d, an image processing device 6 that inputs the images obtained from the retractable cameras 17a and 17b and the image obtained from the laparoscope 5 and combines these images to create a three dimensional image, a three dimensional monitor 7 that outputs the three dimensional image created by the image processing device 6, and an optical tracking sensor 9. The positional relationships of the marks 19 and the corresponding cameras 17 are fixed. The positions of the marks 19 are detected by the optical tracking sensor 9, and the image processing device 6 estimates the distance between the cameras.

Advanced Healthcare Co., Chiba University and Kyocera Optec Co. | Date: 2014-05-08

A technique using a trocar including a retractable camera in which fogging and organic matters are removed to clean a lens of the camera. The trocar includes a pipe portion and a head portion. The pipe portion includes a side opening portion. According to rotation of a changing over mechanism and a shaft, the retractable camera rotates such that the camera is changeable between a stored position and a deployed position by passing through the side opening portion. A wiper blade is fixed to an end face of the side opening portion on a tip side of the trocar. When the retractable camera rotates, a tip of the wiper blade contacts a camera lens in a deformable manner.

The research was carried out by Project Associate Professor SUETSUGU Kenji (Kobe University Graduate School of Science), Associate Professor KAMINAKA Hironori and Research Fellow MIURA Chihiro (Tottori University Faculty of Agriculture), Associate Professor YAMATO Masahide (Chiba University Faculty of Education), and Special Associate Professor SHIGENOBU Shuji (National Institute for Basic Biology). Spontaneous mutation resulting in loss of chlorophyll is a phenomenon seen among many plant species. In normal plant species, albino mutations that lack chlorophyll wither after using up the nutrients stored in their seeds, but albinos of semi-parasitic species can continue to grow and even produce flowers. These albino plants, lacking chlorophyll, become totally dependent on fungi for their survival. Plants that have abandoned photosynthesis and feed off the roots of mushrooms and other fungi are known as mycoheterotrophs. Most mycoheterotrophs are a long way genetically from even the closest autotrophic plants. In addition to the evolutionary adaptation that enabled their parasitic lifestyle, they have various other mutations, making it hard to pinpoint which gene group helped them to gain their parasitic abilities (see figure 1). This study focused on the orchid species Epipactis helleborine. Although this species has developed green leaves and at first glance appears to be able to survive from photosynthesis alone, it is semi-dependent on fungi for carbon. Semi-mycoheterotrophic species such as E. helleborine occasionally undergo spontaneous mutations into albino varieties, totally losing their chlorophyll (see figure 2). The green individuals and the albino individuals have almost identical genome sequences, making them ideal candidates for genetic analysis of mycoheterotrophy (see figure 3). Because albino individuals lack chlorophyll, they are thought to depend more on their parasitic abilities than green individuals. This study investigated the possibility that the genes expressing more in albino varieties are related to mycoheterotrophy (parasitism of fungi). The research team focused on these highly-expressing gene groups. The group carried out transcriptome analysis using RNA extracted from the roots of 3 green individuals and 3 albino individuals of the E. helleborine. The results showed that the gene group linked to mycorrhizal symbiosis in arbuscular mycorrhizal plants and autotrophic orchids is also highly expressed in albino individuals of E. helleborine. Additionally, the expression patterns from multiple genetic groups related to plant hormone biosynthesis showed similarities between albino individuals and plants associated with arbuscular mycorrhizal fungi. These results suggest that mycoheterotrophs may incorporate fungi by using a similar mechanism to those found in other types of mycorrhizal symbiosis. Until now, botanists believed that mycorrhizal symbiosis in mycoheterotrophs used a different mechanism from other types of mycorrhizal symbiosis because of the dramatic partner shift in mycorrhizal fungi. However, this research suggests they may have more mechanisms in common than previously imagined. The findings were published on January 19 in the online edition of Molecular Ecology. Explore further: Plants cheat too: A new species of fungus-parasitizing orchid More information: Kenji Suetsugu et al. Comparison of green and albino individuals of the partially mycoheterotrophic orchidon molecular identities of mycorrhizal fungi, nutritional modes and gene expression in mycorrhizal roots, Molecular Ecology (2017). DOI: 10.1111/mec.14021

News Article | November 4, 2016

Chinese licorice, which is closely related to the plant—Glycyrrhiza glabra—used for licorice candy, is an important component of Chinese traditional medicine. According to Kazuki Saito of CSRS, who led the team, "It is incorporated in approximately 70 percent of the 200 major formulations used in traditional Kampo medicine in Japan. Considering that 90 percent of Japanese physicians prescribe Kampo medicine in their practices, it is easy to see the importance of this plant." The team chose to examine the genome of Chinese licorice rather than other related species partly because it is known to contain the highest concentration of glycyrrhizin, a compound that is associated with the medical properties of the plant, which include anti-inflammatory, anti-cancer, anti-allergic, and anti-viral activities. To conduct the screening, they chose a strain of G. uralensis kept at the Takeda Garden for Medicinal Plant Conservation in Kyoto. Using a combination of long read and short read sequencing, and by comparing the genome to published sequences of other legume species, they predicted that the plant's genome coded just over 34,000 proteins, a number somewhat higher than the 20,000 in the human genome. They focused in particular on two genetic regions—one coding saponins, which are important plant compounds including glycyrrhizin, and the other producing isoflavonoids, which are also known as medicinal components. Through the research, the group demonstrated that there is a close conservation of genes between licorice and other related plants such as barrelclover (s species close to alfalfa) and chickpea, showing that legumes use a small number of genes to create "scaffolds" that allow for the production of an enormous diversity of compounds. Keiichi Mochida, the first author of the paper, says, "Chinese licorice is an important and heavily consumed medicinal plant, and we hope that our work will make it possible to carry out molecular breeding to create strains that will grow sustainably in Japan, and which produce large concentrations of useful compounds such as glycyrrhizin." According to Saito, "We very much hope that our draft genome sequence will facilitate the identification, isolation, and editing of useful genes to improve the agronomic and medicinal traits of licorice through molecular breeding. There remains much to learn about the immense diversity of plant metabolism, and this research will contribute to further progress in that direction." The group plans to do further work to examines differences between the genome of G. uralensis and other licorice species, to further deepen their understanding of the production of useful compounds. The work was carried out by RIKEN CSRS in collaboration with a group including Chiba University, Kochi University, and Osaka University. More information: Keiichi Mochida et al. Draft genome assembly and annotation of, a medicinal legume, The Plant Journal (2016). DOI: 10.1111/tpj.13385

News Article | November 4, 2016

In research published in The Plant Journal, a group of scientists led by researchers from the RIKEN Center for Sustainable Resource Science in Japan have decoded the genome of Glycyrrhiza uralensis, or Chinese licorice, a plant that is important for its use in Chinese medicine and as a natural sweetener. Chinese licorice, which is closely related to the plant--Glycyrrhiza glabra--used for licorice candy, is an important component of Chinese traditional medicine. According to Kazuki Saito of CSRS, who led the team, "It is incorporated in approximately 70 percent of the 200 major formulations used in traditional Kampo medicine in Japan. Considering that 90 percent of Japanese physicians prescribe Kampo medicine in their practices, it is easy to see the importance of this plant." The team chose to examine the genome of Chinese licorice rather than other related species partly because it is known to contain the highest concentration of glycyrrhizin, a compound that is associated with the medical properties of the plant, which include anti-inflammatory, anti-cancer, anti-allergic, and anti-viral activities. To conduct the screening, they chose a strain of G. uralensis kept at the Takeda Garden for Medicinal Plant Conservation in Kyoto. Using a combination of long read and short read sequencing, and by comparing the genome to published sequences of other legume species, they predicted that the plant's genome coded just over 34,000 proteins, a number somewhat higher than the 20,000 in the human genome. They focused in particular on two genetic regions--one coding saponins, which are important plant compounds including glycyrrhizin, and the other producing isoflavonoids, which are also known as medicinal components. Through the research, the group demonstrated that there is a close conservation of genes between licorice and other related plants such as barrelclover (s species close to alfalfa) and chickpea, showing that legumes use a small number of genes to create "scaffolds" that allow for the production of an enormous diversity of compounds. Keiichi Mochida, the first author of the paper, says, "Chinese licorice is an important and heavily consumed medicinal plant, and we hope that our work will make it possible to carry out molecular breeding to create strains that will grow sustainably in Japan, and which produce large concentrations of useful compounds such as glycyrrhizin." According to Saito, "We very much hope that our draft genome sequence will facilitate the identification, isolation, and editing of useful genes to improve the agronomic and medicinal traits of licorice through molecular breeding. There remains much to learn about the immense diversity of plant metabolism, and this research will contribute to further progress in that direction." The group plans to do further work to examines differences between the genome of G. uralensis and other licorice species, to further deepen their understanding of the production of useful compounds. The work was carried out by RIKEN CSRS in collaboration with a group including Chiba University, Kochi University, and Osaka University.

News Article | November 4, 2016

In research published in The Plant Journal, a group of scientists led by researchers from the RIKEN Center for Sustainable Resource Science in Japan have decoded the genome of Glycyrrhiza uralensis, or Chinese licorice, a plant that is important for its use in Chinese medicine and as a natural sweetener. Chinese licorice, which is closely related to the plant -- Glycyrrhiza glabra -- used for licorice candy, is an important component of Chinese traditional medicine. According to Kazuki Saito of CSRS, who led the team, "It is incorporated in approximately 70 percent of the 200 major formulations used in traditional Kampo medicine in Japan. Considering that 90 percent of Japanese physicians prescribe Kampo medicine in their practices, it is easy to see the importance of this plant." The team chose to examine the genome of Chinese licorice rather than other related species partly because it is known to contain the highest concentration of glycyrrhizin, a compound that is associated with the medical properties of the plant, which include anti-inflammatory, anti-cancer, anti-allergic, and anti-viral activities. To conduct the screening, they chose a strain of G. uralensis kept at the Takeda Garden for Medicinal Plant Conservation in Kyoto. Using a combination of long read and short read sequencing, and by comparing the genome to published sequences of other legume species, they predicted that the plant's genome coded just over 34,000 proteins, a number somewhat higher than the 20,000 in the human genome. They focused in particular on two genetic regions -- one coding saponins, which are important plant compounds including glycyrrhizin, and the other producing isoflavonoids, which are also known as medicinal components. Through the research, the group demonstrated that there is a close conservation of genes between licorice and other related plants such as barrelclover (s species close to alfalfa) and chickpea, showing that legumes use a small number of genes to create "scaffolds" that allow for the production of an enormous diversity of compounds. Keiichi Mochida, the first author of the paper, says, "Chinese licorice is an important and heavily consumed medicinal plant, and we hope that our work will make it possible to carry out molecular breeding to create strains that will grow sustainably in Japan, and which produce large concentrations of useful compounds such as glycyrrhizin." According to Saito, "We very much hope that our draft genome sequence will facilitate the identification, isolation, and editing of useful genes to improve the agronomic and medicinal traits of licorice through molecular breeding. There remains much to learn about the immense diversity of plant metabolism, and this research will contribute to further progress in that direction." The group plans to do further work to examines differences between the genome of G. uralensis and other licorice species, to further deepen their understanding of the production of useful compounds. The work was carried out by RIKEN CSRS in collaboration with a group including Chiba University, Kochi University, and Osaka University.

Uzawa A.,Chiba University | Masahiro M.,Chiba University | Kuwabara S.,Chiba University
Brain Pathology | Year: 2014

Neuromyelitis optica (NMO) is characterized by severe optic neuritis and longitudinally extensive transverse myelitis. The discovery of an NMO-specific autoantibody to the aquaporin-4 (AQP4) water channel has improved knowledge of NMO pathogenesis. Many studies have focused on inflammatory and pathological biomarkers of NMO, including cytokines and chemokines. Increased concentrations of T helper (Th)17- and Th2-related cytokines and chemokines may be essential factors for developing NMO inflammatory lesions. For example, interleukin-6 could play important roles in NMO pathogenesis, as it is involved in the survival of plasmablasts that produce anti-AQP4 antibody in peripheral circulation and in the enhancement of inflammation in the central nervous system. Therefore, assessment of these useful biomarkers may become a supportive criterion for diagnosing NMO. Significant advances in the understanding of NMO pathogenesis will lead to the development of novel treatment strategies. This review focuses on the current advances in NMO immunological research, particularly that of cytokines and chemokines. © 2013 International Society of Neuropathology.

Nara Y.,Chiba University
International Journal of Advanced Intelligence Paradigms | Year: 2010

This paper aims to examine the status quo of people's perception or coping with earthquakes, and the effects of risk experience and risk information to promote risk management in China. Questionnaire surveys were carried out before and after the Sichuan earthquake in China, and the same surveys were also conducted in Japan and the USA. The survey results clarified that the respondents in China showed lower levels of anxiety and higher self-evaluation of risk coping than did the Japanese respondents. The effect of risk experience was observed as the awareness and counter-measures with respect to earthquakes improved, especially among Chengdu's residents after the Sichuan earthquake. Significant effect from obtaining information on actual risk management action was also observed. Copyright © 2010 Inderscience Enterprises Ltd.

Uzawa A.,Chiba University | Mori M.,Chiba University | Masuda S.,Chiba University | Kuwabara S.,Chiba University
Archives of Neurology | Year: 2011

Objective: To evaluate the degree of blood-brain barrier disruption in patients with neuromyelitis optica (NMO) and to clarify whether the levels of soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vascular cell adhesion molecule 1 (sVCAM-1) in patients with NMO can be useful biomarkers for blood-brain barrier breakdown. Design: Descriptive historical cohort. Setting: Department of Neurology, Graduate School of Medicine, Chiba University. Patients: The levels of sICAM-1 and sVCAM-1 in 25 patients with NMO, 21 patients with multiple sclerosis, and 20 patients with other noninflammatory neurologic disorders in the serum and cerebrospinal fluid (CSF) were measured using a multiplexed fluorescent magnetic bead-based immunoassay. Main Outcome Measures: Levels of the soluble adhesion molecules in serum and CSF and their associations with blood-brain barrier disruption. Results: The CSF levels of sICAM-1 and sVCAM-1 increased in patients with NMO compared with patients with multiple sclerosis and other noninflammatory neurologic disorders (P<.001), and serum levels of sICAM-1 increased in patients with NMO compared with healthy control individuals (P=.003). The CSF sICAM-1 levels from patients with NMO were correlated with the albumin quotient (P=.02) and the presence of lesions detected via gadolinium-enhanced magnetic resonance imaging. Conclusions: Severe blood-brain barrier breakdown occurs in patients with NMO. Measuring adhesion molecules is useful to evaluate this barrier disruption. ©2011 American Medical Association. All rights reserved.

Furuse T.,Red Cross | Hashimoto K.,Chiba University
Annals of General Psychiatry | Year: 2010

Background: Delirium in older adults is a common and serious acute neuropsychiatric syndrome, with core features of inattention and global cognitive impairment. Although antipsychotic drugs are the medications most frequently used to treat this syndrome, these drugs are associated with a variety of adverse events, including sedation, extrapyramidal side effects, and cardiac arrhythmias.Methods: We report on two cases in which monotherapy of the selective serotonin reuptake inhibitor and sigma-1 receptor agonist fluvoxamine was effective in ameliorating the delirium of patients with Alzheimer's disease.Results: Delirium Rating Scale (DRS) scores in the two patients with Alzheimer's disease decreased after fluvoxamine monotherapy.Conclusion: Doctors should consider that fluvoxamine could be an alternative approach in treating delirium in patients with Alzheimer's disease because of the risk of extrapyramidal side effects by antipsychotic drugs. © 2010 Furuse and Hashimoto; licensee BioMed Central Ltd.

Hoshino I.,Chiba University
Surgery today | Year: 2013

Epigenetic changes, such as DNA methylation and histone modifications, regulate gene expression. It is speculated that investigating the fundamental epigenetic mechanisms and their gene regulation will promote a better understanding of cancer development. The idea of epigenetic modification has been extended to microRNAs (miRs). MiRs are single-stranded RNA molecules, about 19-25 ribonucleotides in length, which regulate gene expression post-transcriptionally and can act as tumor suppressors or oncogenes. We review the most recent findings related to their mechanisms of action, the modification of miR expression, and their relationship to cancer. We also discuss the potential application of miRs in the clinical setting, such as for biomarkers and therapy.

Kendoul F.,Chiba University | Yu Z.,Beijing Jiaotong University | Nonami K.,Chiba University
Journal of Field Robotics | Year: 2010

Small unmanned aerial vehicles (UAVs) are becoming popular among researchers and vital platforms for several autonomous mission systems. In this paper, we present the design and development of a miniature autonomous rotorcraft weighing less than 700 g and capable of waypoint navigation, trajectory tracking, visual navigation, precise hovering, and automatic takeoff and landing. In an effort to make advanced autonomous behaviors available to mini- and microrotorcraft, an embedded and inexpensive autopilot was developed. To compensate for the weaknesses of the low-cost equipment, we put our efforts into designing a reliable modelbased nonlinear controller that uses an inner-loop outer-loop control scheme. The developed flight controller considers the system's nonlinearities, guarantees the stability of the closed-loop system, and results in a practical controller that is easy to implement and to tune. In addition to controller design and stability analysis, the paper provides information about the overall control architecture and the UAV system integration, including guidance laws, navigation algorithms, control system implementation, and autopilot hardware. The guidance, navigation, and control (GN&C) algorithms were implemented on a miniature quadrotor UAV that has undergone an extensive program of flight tests, resulting in various flight behaviors under autonomous control from takeoff to landing. Experimental results that demonstrate the operation of the GN&C algorithms and the capabilities of our autonomous micro air vehicle are presented. © 2009 Wiley Periodicals, Inc.

Koga K.,Chiba University | Iwasaki Y.,Chiba University
Journal of Physiological Anthropology | Year: 2013

Background: Numerous studies have reported on the healing powers of plants and nature, but there have not been so many instances of experimental research. In particular, there are very few psychological and physiological studies using tactile stimuli. This study examines the psychological and physiological effects of touching plant foliage by using an evaluation profile of the subjects' impressions and investigating cerebral blood flow.Methods: The subjects were 14 young Japanese men aged from 21 to 27 years (mean ± standard deviation: 23.6 ± 2.4). With their eyes closed, the subjects touched four different tactile samples including a leaf of natural pothos (Epipremnum aureum). The physiological indices were compared before and after each stimulus. Psychological indices were obtained using a 'semantic differential' method.Results: The fabric stimulus gave people 'soft' and 'rough' impressions, 'kind', 'peaceful' and 'pleasant' feelings psychologically, and a sense of physiological calm. On the other hand, the metal stimulus gave people 'cold', 'smooth' and 'hard' impressions and an image of something 'artificial'. The metal stimulus caused a stress response in human cerebral blood flow although its evaluation in terms of 'pleasant or unpleasant' was neutral. There were no remarkable differences between the stimuli of natural and artificial pothos compared with other types of stimulus psychologically. However, only the natural pothos stimulus showed a sense of physiological calm in the same appearance as the fabric stimulus.Conclusions: This study shows that people experience an unconscious calming reaction to touching a plant. It is to be concluded that plants are an indispensable element of the human environment. © 2013 Koga and Iwasaki; licensee BioMed Central Ltd.

Sato F.,Chiba University | Sato S.,Chiba University
Catalysis Communications | Year: 2012

Vapor-phase dehydration of 1,4- and 1,5-alkanediols was investigated over three scandium ytterbium mixed oxides, Sc 2-xYb xO 3 (x = 0.5, 1.0, and 1.5), to produce the corresponding unsaturated alcohols. In the dehydration of 1,5-pentanediol, Sc 0.5Yb 1.5O 3 was more active than simple rare earth oxides such as Sc 2O 3, Lu 2O 3, Yb 2O 3, and Tm 2O 3. The selectivity to 4-penten-1-ol surpassed 80 mol% over the Sc 2-xYb xO 3 catalysts. The highest formation rate of 4-penten-1-ol was obtained at x = 1.5 and affected by lattice parameter of cubic bixbyite Sc 2-xYb xO 3. In the dehydration of 1,4-butanediol, however, Tm 2O 3 was the most active among the catalysts. © 2012 Elsevier B.V.

Sumantyo J.T.S.,Chiba University
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2014

This paper introduces the progress of circularly polarized synthetic aperture radar (CP-SAR) development in Center for Environmental Remote Sensing, Chiba University, Japan for unmanned aerial vehicle (UAV, JX series) and microsatellites (GAIA series). This sensor will be used to monitor global land deformation and disaster area. © 2014 IEEE.

Sashida G.,Chiba University | Iwama A.,Chiba University
International Journal of Hematology | Year: 2012

Epigenetic regulation is required not only for development, but also for tissue homeostasis, which is maintained via the self-renewal and differentiation of somatic stem cells. Accumulating evidence suggests that epigenetic regulators play critical roles in the maintenance of both self-renewing hematopoietic stem cells and leukemic stem cells. Recent genome-wide comprehensive analyses have identified mutations in epigenetic regulator genes, including genes whose products modify DNA and histones in hematological malignancies. Among these epigenetic regulators, repressive histone modifications by Polycomb-group complexes have been most fully characterized in hematopoietic stem cells, and are recognized as general regulators of stem cells. Hematopoietic stem cells are controlled by both cell-intrinsic and -extrinsic regulators, including transcription factors, signal transduction pathways, and niche factors. However, there is little insight into the mechanism of how epigenetic regulators act in concert with these factors to ensure blood homeostasis. In this review, we highlight recent findings in epigenetic regulation of hematopoiesis with emphasis on the role of Polycomb-group proteins and DNA-methylation modulators in hematopoietic stem cells and their progeny. © The Japanese Society of Hematology 2012.

This study draws on video recordings of 12 massage therapy sessions that took place in Japan. During massage therapy sessions, therapists produce utterances regarding massaging procedures. This study investigates the ways such procedural utterances are syntactically constructed in different sequential contexts and bodily configurations. The procedural utterances take three forms: the request form, the proposal form, and the announcement form. Two observations have been made. First, various movements, including the movements that are mentioned in the procedural utterances, are initiated during the utterances. Second, the placement of the different syntactic forms of procedural utterances varies relative to the stage of the ongoing therapy session and the concurrent body movement. I argue that procedural utterances are constructed normatively sensitively to the tactile orientations that accompany bodily manipulations and that this normative sensitivity can be a resource for the negotiation between the therapist and the client regarding the incipient procedure. © 2016 Elsevier B.V.

Shimizu T.,Chiba University | Tsutsuki H.,Chiba University | Matsumoto A.,Chiba University | Nakaya H.,Chiba University | Noda M.,Chiba University
Molecular Microbiology | Year: 2012

In enterohaemorrhagic Escherichia coli (EHEC) O157, there are two types of anaerobic nitric oxide (NO) reductase genes, an intact gene (norV) and a 204bp deletion gene (norVs). Epidemiological analysis has revealed that norV-type EHEC are more virulent than norVs-type EHEC. Thus, to reveal the role of NO reductase during EHEC infection, we constructed isogenic norV-type and norVs-type EHEC mutant strains. Under anaerobic conditions, the norV-type EHEC was protected from NO-mediated growth inhibition, while the norVs-type EHEC mutant strain was not, suggesting that NorV of EHEC was effective in the anaerobic detoxification. We then investigated the role of NO reductase within macrophages. The norV-type EHEC produced a lower NO level within macrophages compared with the norVs-type EHEC. Moreover, the norV-type EHEC resulted in higher levels of Shiga toxin 2 (Stx2) within macrophages compared with the norVs-type EHEC. Finally, the norV-type EHEC showed a better level of survival than the norVs-type EHEC. These data suggest that the intact norV gene plays an important role for the survival of EHEC within macrophages, and is a direct virulence determinant of EHEC. © 2012 Blackwell Publishing Ltd.

Kobayashi G.,Chiba University
Computational Statistics and Data Analysis | Year: 2014

When the likelihood functions are either unavailable analytically or are computationally cumbersome to evaluate, it is impossible to implement conventional Bayesian model choice methods. Instead, approximate Bayesian computation (ABC) or the likelihood-free method can be used in order to avoid direct evaluation of the intractable likelihoods. This paper proposes a new Markov chain Monte Carlo (MCMC) method for model choice. This method is based on the pseudo-marginal approach and is appropriate for situations where the likelihood functions for the competing models are intractable. This method proposes jumps between the models with different dimensionalities without matching the dimensionalities. Therefore, it enables the construction of a flexible proposal distribution. The proposal distribution used in this paper is convenient to implement and works well in the context of ABC. Because the posterior model probabilities can be estimated simultaneously, it is expected that the proposed method will be useful, especially when the number of competing models is large. In the simulation study, a comparison between the proposed and existing methods is presented. The method is then applied to the model choice problem for an exchange return model. © 2014 Elsevier B.V. All rights reserved.

Fused in sarcoma/translocated in liposarcoma (FUS/TLS) is one of causative genes for familial amyotrophic lateral sclerosis (ALS). In order to identify binding partners for FUS/TLS, we performed a yeast two-hybrid screening and found that protein arginine methyltransferase 1 (PRMT1) is one of binding partners primarily in the nucleus. In vitro and in vivo methylation assays showed that FUS/TLS could be methylated by PRMT1. The modulation of arginine methylation levels by a general methyltransferase inhibitor or conditional over-expression of PRMT1 altered slightly the nucleus-cytoplasmic ratio of FUS/TLS in cell fractionation assays. Although co-localized primarily in the nucleus in normal condition, FUS/TLS and PRMT1 were partially recruited to the cytoplasmic granules under oxidative stress, which were merged with stress granules (SGs) markers in SH-SY5Y cell. C-terminal truncated form of FUS/TLS (FUS-dC), which lacks C-terminal nuclear localization signal (NLS), formed cytoplasmic inclusions like ALS-linked FUS mutants and was partially co-localized with PRMT1. Furthermore, conditional over-expression of PRMT1 reduced the FUS-dC-mediated SGs formation and the detergent-insoluble aggregates in HEK293 cells. These findings indicate that PRMT1-mediated arginine methylation could be implicated in the nucleus-cytoplasmic shuttling of FUS/TLS and in the SGs formation and the detergent-insoluble inclusions of ALS-linked FUS/TLS mutants. © 2012 Yamaguchi, Kitajo.

Yashiro K.,Chiba University
2015 International Symposium on Antennas and Propagation, ISAP 2015 | Year: 2015

The scattering of E-polarized plane wave from a finite array of axially magnetized ferrite cylinders is analysed based on the method of moments with global basis functions and Galerkin approach. To do so, the scattered wave is expressed in terms of the equivalent surface current. Furthermore, the surface impedance is introduced so that the boundary condition is imposed at the surfaces of cylinders in the unified manner as dielectric or conducting cylinders. Some numerical examples are given. © 2015 The Institute of Electronics, Information and Comm.

Mitsukawa N.,Chiba University | Satoh K.,Chiba University
Journal of Craniofacial Surgery | Year: 2012

Cystic lymphangioma is a congenital malformation occurring most frequently in the necks of infants and young children. It is histologically benign, but the lesion can extend deep into the tissue. Thus, surgical treatment is often difficult. In recent years, OK-432 sclerotherapy has become the first-line therapy for cystic lymphangioma, and many reports have discussed its effectiveness. However, it is difficult to achieve a complete response to OK-432 in polycystic cases and cases with small cystic areas, and it is sometimes ineffective. In the current study, we performed a new combination therapy on 5 cases of cystic lymphangioma of the face and neck. In this combination therapy, we ruptured the cyst wall of lymphangioma using a liposuction device and subsequently used OK-432 to induce inflammation and to cause adhesion of cyst walls. The combination therapy produced very good results. None of the patients had any major complication or recurrence. All patients had lymphangiomas that markedly reduced in size. This new method can be performed regardless of the cyst type of lymphangioma and is thought to be a useful therapy. Copyright © 2012 by Mutaz B. Habal, MD.

Iinuma M.,Chiba University | Moriyama K.,Chiba University | Togo H.,Chiba University
Tetrahedron | Year: 2013

The oxidation of secondary alcohols and primary alcohols with two novel ion-supported (diacetoxyiodo)benzenes (IS-DIBs) A and B in the presence of a catalytic amount of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) in dichloromethane at room temperature proceeded efficiently to provide the corresponding ketones and aldehydes, respectively, in good yields. The oxidative reaction of N,N-diisopropylbenzylamines with those IS-DIBs was also carried out to generate the corresponding aromatic aldehydes in good yields. In addition, the Hofmann rearrangement of primary amides in methanol under basic conditions and the oxidative 1,2-rearrangement of propiophenones in trimethyl orthoformate under acidic conditions with those IS-DIBs provided the corresponding methyl carbamates and methyl 2-arylpropanoates, respectively, in good yields. Moreover, treatment of acetophenones with those IS-DIBs in the presence of trifluoromethanesulfonic acid in acetonitrile generated the corresponding 5-aryl-2-methyloxazoles in good yields. In those five reactions, the desired products were obtained in good yields with high purity by simple extraction of the reaction mixture with diethyl ether and subsequent removal of the solvent from the extract. Moreover, ion-supported iodobenzenes, which were the co-products derived from IS-DIBs in the present oxidative reactions, were recovered in good yields and could be re-oxidized to IS-DIBs A and B for reuse in the same oxidative reactions. © 2013 Elsevier Ltd. All rights reserved.

Kawagoe Y.,Chiba University | Moriyama K.,Chiba University | Togo H.,Chiba University
Tetrahedron | Year: 2013

Ion-supported Ph3P, 4-(diphenylphosphino)benzyltrimethylammonium bromide (IS-Ph3P), could be used for the facile amidation of a wide range of carboxylic acids with amines in the presence of bromotrichloromethane to provide the corresponding amides in good yields. In the present reaction, the desired amides were obtained in good yields with high purity by simple extraction of the reaction mixture with diethyl ether or chloroform and subsequent removal of the solvent from the extract. Moreover, ion-supported Ph3PO (IS-Ph3PO), which was a co-product derived from IS-Ph3P in the present reductive condensation, was recovered in high yield and could be reduced to IS-Ph3P for reuse in the same amidation of carboxylic acid.© 2013 Elsevier Ltd. All rights reserved.

Yamano Y.,Chiba University | Iizuka M.,Chiba University
IEEE Transactions on Dielectrics and Electrical Insulation | Year: 2011

Resistance to the electrical tree in the insulating material of mixed addition polymer nanocomposite was studied under ac high-voltage application. The polymer nanocomposite was made by the mixed addition of Al2O3 nanoparticle ('Al') and phthalocyanine compound ('Pc') into LDPE. Any coupling agent to avoid the clusters of 'Al' and 'Pc' was not used in the preparation of the test sample. The experimental results indicated that the tree initiation voltages (TIVs) for the 'Pc' and 'Al' mixed addition and the 'Pc' single addition (LDPE with 'Pc' only) were about 1.8 times higher than that for the base polymer. However, TIV for the 'Al' single addition did not significantly increase. The results suggested that the increase in TIV for the mixed addition composite is due to the existence of 'Pc' in the polymer, the mechanism of which was discussed basing on the effects of large π-electron cloud in the molecule of 'Pc' and the effect of semiconductive characteristics of 'Pc' crystallite. On the other hand, the period of time from the tree initiation to the breakdown for the mixed addition was almost 10 times longer than that for the base polymer. In the cases of the single addition, the period of time to the breakdown for the 'Al' single addition was about 3 times longer than that for the base polymer, and the period of time for the 'Pc' single addition was almost the same as that for the base polymer. AFM observation suggested that the well dispersion of 'Al' (nanoparticle) in the polymer is achieved in the mixed addition composite which leads to the wide area of the interface between 'Al' and LDPE. The wide area of the interface was found to control the propagation of tree and accordingly provides the long period of time to breakdown. Consequently, both the increase in TIV and the long period of time to the breakdown were obtained by the mixed addition polymer nanocomposite. © 2011 IEEE.

It is essential to perform electromyography and nerve-conduction studies for diagnosis amyotrophic lateral sclerosis (ALS), but these conventional electrophysiologic methods cannot be used for studies on the mechanism underlying ALS. The recently developed nerve-excitability test can provide new insights into the pathophysiology of this disease. Fasciculation is one of the characteristic features of ALS. Ectopic firing of motor units originates usually from the motor nerve terminals and occasionally from the motor neurons, indicating a widespread abnormality in axonal excitability. ALS is a multifactorial disease in which some genetic abnormalities and environmental factors lead to cell death through a complex cascade, which includes oxidative stress, mitochondrial dysfunction, excitotoxicity, and impaired axonal transport. It is important to elucidate the pathophysiology of axonal excitability in ALS because increased axonal excitability enhances oxidative stress and excitotoxicity, ultimately contributing to motor neuron death. To date, 2 axonal ion channel abnormalities have been identified: (1) increased persistent sodium currents and (2) reduced potassium currents; both abnormalities cause an increase in axonal excitability and are responsible for fasciculations. The results for excitability testing in such patients are characterized by the following features: (1) a prolonged strength-duration time constant, which suggests increased persistent sodium currents; (2) greater threshold changes in depolarizing threshold electrotonus; and (3) greater supernormality, which suggests impaired potassium channels. The altered axonal properties in patients with ALS may provide new insights into the pathophysiology of ALS and have implications for the development of ion channel modulators as therapeutic options for patients with ALS.

Abe D.,Chiba University | Sasanuma Y.,Chiba University
Acta Crystallographica Section E: Structure Reports Online | Year: 2013

The title compound, C18H18O2S2, which lies on an inversion center, adopts a gauche+-trans-trans- trans-gauche- (g+ tttg-) conformation in the S - CH2 - CH2 - CH2 - CH2 - S bond sequence. In the crystal, molecules are packed in a herringbone arrangement through intermolecular C - H⋯π interactions.

Weng J.,Chiba University | Shimobaba T.,Chiba University | Okada N.,Chiba University | Nakayama H.,Japan National Astronomical Observatory | And 3 more authors.
Optics Express | Year: 2012

We report the generation of a real-time large computer generated hologram (CGH) using the wavefront recording plane (WRP) method with the aid of a graphics processing unit (GPU). The WRP method consists of two steps: the first step calculates a complex amplitude on a WRP that is placed between a 3D object and a CGH, from a three-dimensional (3D) object. The second step obtains a CGH by calculating diffraction from the WRP to the CGH. The disadvantages of the previous WRP method include the inability to record a large three-dimensional object that exceeds the size of the CGH, and the difficulty in implementing to all the steps on a GPU. We improved the WRP method using Shifted-Fresnel diffraction to solve the former problem, and all the steps could be implemented on a GPU. We show optical reconstructions from a 1,980×1,080 phase only CGH generated by about 3 × 104 object points over 90 frames per second. In other words, the improved method obtained a large CGH with about 6 mega pixels (1,980×1,080×3) from the object points at the video rate. © 2012 Optical Society of America.

Goto Y.,Chiba University | Kurozumi A.,Chiba University | Enokida H.,Kagoshima University | Ichikawa T.,Chiba University | Seki N.,Chiba University
International Journal of Urology | Year: 2015

microRNAs, a class of small non-coding RNAs, regulate protein-coding gene expression by repressing translation or cleaving RNA transcripts in a sequence-specific manner. A growing body of evidence suggests that microRNAs contribute to prostate cancer development, progression and metastasis. Based on reports describing microRNA expression signatures, several differentially expressed microRNAs have been discovered. In the present review, eight genome-wide microRNA expression signatures were used to select aberrantly expressed microRNAs (i.e. upregulated and downregulated microRNAs) in prostate cancer clinical specimens. Also, we mapped these selected microRNAs in the human genome. Interestingly, some clustered microRNAs, such as miR-221/222, miR-143/145, miR-23b/27b/24-1 and miR-1/133a, are frequently downregulated in cancer tissues, and recent studies have shown that these clustered microRNAs function as tumor suppressors. We also discuss the functional significance of the differentially expressed microRNAs and the molecular pathways/targets regulated by these microRNAs. These recent findings of microRNAs in prostate cancer will facilitate the development of effective strategies for microRNA-based therapeutics for the treatment of prostate cancer. © 2015 The Japanese Urological Association.

Shimobaba T.,Chiba University | Masuda N.,Chiba University | Ito T.,Chiba University
Optics Express | Year: 2012

Fresnel diffraction calculation on an arbitrary shape surface is proposed. This method is capable of calculating Fresnel diffraction from a source surface with an arbitrary shape to a planar destination surface. Although such calculation can be readily calculated by the direct integral of a diffraction calculation, the calculation cost is proportional to O(N2) in one dimensional or O(N4) in two dimensional cases, where N is the number of sampling points. However, the calculation cost of the proposed method is O(N logN) in one dimensional or O(N2 logN) in two dimensional cases using non-uniform fast Fourier transform. © 2012 Optical Society of America.

Werner P.,University of Fribourg | Werner P.,ETH Zurich | Casula M.,University Pierre and Marie Curie | Miyake T.,Japan National Institute of Advanced Industrial Science and Technology | And 6 more authors.
Nature Physics | Year: 2012

Superconductivity has recently been discovered in several families of iron-based compounds, but despite intense research even such basic electronic properties of these materials as Fermi surfaces, effective electron masses and orbital characters are still subject to debate. Here, we address an issue that has not been considered before, namely the consequences of dynamical screening of the Coulomb interactions between Fe d electrons. We demonstrate that dynamical screening effects are important not only for higher-energy spectral features, such as correlation satellites seen in photoemission spectroscopy, but also for the low-energy electronic structure. Our analysis indicates that BaFe 2As 2 is a strongly correlated compound with strongly doping- and temperature-dependent properties. In the hole-overdoped regime an incoherent metal is found, whereas Fermi-liquid behaviour is recovered in the undoped compound. At optimal doping, the self-energy exhibits an unusual square-root energy dependence, which leads to strong band renormalizations near the Fermi level. © 2012 Macmillan Publishers Limited. All rights reserved.

Shauri R.L.A.,Chiba University | Nonami K.,Chiba University
Assembly Automation | Year: 2011

Purpose - The purpose of this paper is to propose an assembly robot that exhibits specific human-like skills, with minimal structural cost and a number of external sensors. Design/methodology/approach - The authors have employed vision processing using multiple cameras to determine targets and postures and propose strategies to determine the pose of a target and to prevent collisions between the fingers and obstacles in an environment with mixed objects. Furthermore, a dynamic trajectory planner integrates the vision and force sensors of the robot hand for the assigned task. Findings - The authors obtained satisfactory experimental results for autonomous real-time grasping and screwing. The results verified the capability of the robot for handling small objects. Research limitations/implications - More effective robotic manipulation requires a higher degree of target orientation data, which will be a future study of this research. Practical implications - Practicality has been established through results, indicating the capability of the robot to implement human-like skilled manipulation of small objects. This can potentially reduce the high labor cost associated with the small-scale manufacture of custom-made products. Originality/value - Screwing of nuts of minimum M2 size (diameter, 4.6?mm) and M8-M10 bolts (head diameter, 15-19.6?mm; length, 50-80?mm) by cooperating two seven-link arm manipulators and three-fingered hands shows the robot's capability to manipulate small objects. Copyright © 2011 Emerald Group Publishing Limited. All rights reserved.

Omatsu T.,Chiba University | Okida M.,Chiba University | Lee A.,Macquarie University | Pask H.M.,Macquarie University
Applied Physics B: Lasers and Optics | Year: 2012

We have directly measured thermal lensing in a continuous-wave Nd-doped GdVO 4 self-Raman laser under diode pumping at 808 and 879 nm. Thermal lensing increased significantly when generating first-Stokes emission, this most likely originating from impurity absorption and/or excited-state absorption at high pump powers. Pumping at 879 nm significantly reduced thermal lens effects in the laser crystal compared with pumping at 808 nm. © 2012 Springer-Verlag.

Miyauchi-Nomura S.,Chiba University | Obinata T.,Chiba University | Sato N.,Chiba University
Cytoskeleton | Year: 2012

Cofilin is an actin regulatory protein that plays a critical role in actin filament dynamics in a variety of cells. We have previously demonstrated that excess cofilin in skeletal muscle cells leads to disruption of actin filaments, followed by actin-cofilin rod formation in the cytoplasm. In this study, to further clarify the role of cofilin in actin assembly during myofibrillogenesis, cofilin expression was suppressed in cultured chicken skeletal muscle cells. First, we confirmed that turnover of cofilin in myotubes was much higher than that of actin, and that the cofilin level could be decreased drastically within 2 days when cofilin de novo synthesis was suppressed. Next, cofilin expression in individual myotubes was suppressed by introducing antisense morpholino oligonucleotides into the cells by microinjection. Cofilin depletion at the early phase of myofibrillogenesis caused abnormal actin aggregates in myotubes and impaired actin organization into cross-striated myofibril structures. However, when cofilin expression was suppressed in developed myotubes, actin localization in striated myofibrils was scarcely affected. These results indicate that cofilin plays a critical role in the regulation of actin assembly at the early process of myofibrillogenesis. © 2012 Wiley Periodicals, Inc.

Kikumura A.,Chiba University | Ishikawa T.,Chiba University | Norose K.,Chiba University
British Journal of Ophthalmology | Year: 2012

Background/Aims: To investigate the molecules possibly influencing the recruitment and migration of leucocytes in murine ocular toxoplasmosis, the kinetics of the messenger RNA expression levels of cytokines, chemokines, chemokine receptors and adhesion molecules in the retina were analysed. Methods: Retina and brain were obtained sequentially from Toxoplasma gondii Fukaya strain-infected wild-type (WT) C57BL/6 and interferon gamma (IFN-γ) knockout (GKO) mice of the same background. The mRNA expression levels of these molecules were analysed by real-time PCR assay. Results: In the retina of WT mice the expression levels of IFN-γ, interleukin 17A, CCL3, CCL4, CCL5, CXCL1, CXCL2, CXCL10, CCR5, CCR7, CXCR2, CXCR3 and intracellular adhesion molecule 1 increased, reaching peaks approximately 14-28 days after infection. The expression levels of CXCR4 and CXCR5 were absent and very low, respectively, during the infection. In the brain of WT mice, the kinetic patterns of these expression levels tended to be the same as in the retina except CXCR4. On the other hand, in GKO mice these molecules, except CXCL1, CXCL2 and CXCR2, remained at basal levels. Conclusion: In murine ocular toxoplasmosis, cytokines, chemokines, chemokine receptors and adhesion molecules were involved in the pathogenesis, and IFN-γ played a pivotal role.

Young R.S.L.,Texas Tech University Health Sciences Center | Kimura E.,Chiba University
Documenta Ophthalmologica | Year: 2010

The aim of the study was to describe a theory and method for inferring the statistical significance of a visually evoked cortical potential (VEP) recording. The statistical evaluation is predicated on the pre-stimulus VEP as estimates of the cortical potentials expected when the stimulus does not produce an effect, a mathematical transform to convert the voltages into standard deviations from zero, and a time-series approach for estimating the variability of between-session VEPs under the null hypothesis. Empirical and Monte Carlo analyses address issues concerned with testability, statistical validity, clinical feasibility, as well as limitations of the proposed method. We conclude that visual electrophysiological recordings can be evaluated as a statistical study of n = 1 subject using time-series analysis when confounding effects are adequately controlled. The statistical test can be performed on either a single VEP or the difference between pairs of VEPs.

Nobeshima T.,Chiba University | Morimoto T.,Chiba University | Nakamura K.,Chiba University | Kobayashi N.,Chiba University
Journal of Materials Chemistry | Year: 2010

An AC voltage-driven electrochemiluminescent (ECL) device containing a ruthenium(ii) complex as luminescent species was fabricated, and advantages of the AC-driven method such as electrochemical and emission response were studied. The cell can be easily fabricated by simply placing the emitting solution between electrodes. The emission turn-on response time and emission intensity were dramatically improved by introducing the AC method. The turn-on response time was speeded up by increasing applied frequency. 4 ms was achieved at 200 Hz, which was much faster than the DC method (1.5 s). The current efficiency for the emission was estimated to be 0.59 cd A-1. The mechanism of the improved ECL properties was discussed from a viewpoint of electrochemical reaction. © 2010 The Royal Society of Chemistry.

BACKGROUND/PURPOSE:: To determine the relationship between the alterations in the preoperative morphology of the retinal pigment epithelium (RPE) and the postoperative recovery after surgery to close an idiopathic macular hole (MH). METHODS:: Retrospective interventional case series. Fifty-nine eyes of 59 patients with an idiopathic MH were studied. Pars plana vitrectomy was performed with the removal of the internal limiting membrane. The best-corrected visual acuity was measured, and the retinal morphology, including the presence of small RPE protrusions at the bottom of MH, was determined by spectral domain optical coherence tomography before and at 1, 3, and 6 months postoperatively. RESULTS:: The mean age of the patients was 66.7 years. Forty eyes (68%) had preoperative alterations of the RPE. The minimal (P < 0.001) and the base (P < 0.001) diameters of the MH were significantly larger in eyes with preoperative RPE alterations. The best-corrected visual acuity was significantly worse at baseline (P = 0.014) and at 6 months postoperatively (P = 0.048) in the eyes with RPE alterations. The defect of the ellipsoid zone was significantly longer in eyes with baseline RPE alterations at 1, 3, and 6 months postoperatively (P < 0.001, P = 0.001, and P = 0.032). CONCLUSION:: The presence of RPE protrusions at baseline was significantly correlated with slower morphologic recovery and poorer visual acuity after MH closure. © 2016 by Ophthalmic Communications Society, Inc.

Nishikawa T.,Chiba University | Tsuyuguchi T.,Chiba University | Sakai Y.,Chiba University | Sugiyama H.,Chiba University | And 2 more authors.
Gastrointestinal Endoscopy | Year: 2013

Background: The diagnostic accuracy of peroral video-cholangioscopy for indeterminate biliary lesions has not been determined in a prospective study. Objective: To evaluate and compare the diagnostic accuracy of the peroral video-cholangioscopic visual findings for indeterminate biliary lesions with that of the cholangioscopy-guided forceps biopsy findings. Design: Prospective cohort study. Setting: Tertiary-care referral center. Patients: Patients who showed indeterminate biliary lesions on endoscopic retrograde cholangiography underwent peroral video-cholangioscopy for diagnosis. Intervention: Each patient underwent peroral video-cholangioscopy with cholangioscopy-guided forceps biopsy. Main Outcome Measurements: The accuracy of diagnosis by the peroral video-cholangioscopic visual findings and cholangioscopy-guided forceps biopsy findings compared with that of the final diagnosis by other methods (malignant or benign). Results: Thirty-three patients were enrolled, and the final diagnoses revealed that the lesions were malignant in 21 patients. All procedures were technically successful, and fine views were obtained in all patients. Procedure-related complications occurred in 2 patients (6.1%), but these complications were mild. The sensitivity, specificity, and accuracy were 100%, 91.7%, and 97.0%, respectively, for the peroral video-cholangioscopic visual findings and 38.1%, 100%, and 60.6%, respectively, for the cholangioscopy-guided forceps biopsy findings, and a significant difference was observed in the accuracy (P =.0018). Limitations: This was not a blinded study. No comparison was made with other diagnostic modalities involving tissue sampling. Conclusion: The diagnostic accuracy of the peroral video-cholangioscopic visual findings for indeterminate biliary lesions was excellent and significantly higher than that of the cholangioscopy-guided forceps biopsy findings. The accuracy of the cholangioscopy-guided forceps biopsy was insufficient, but the technique had an excellent specificity. © 2013 American Society for Gastrointestinal Endoscopy.

Inoue Y.,Chiba University | Shimojo N.,Chiba University
Seminars in Immunopathology | Year: 2015

Allergies are characterized by a hypersensitive immune reaction to originally harmless antigens. In recent decades, the incidence of allergic diseases has markedly increased, especially in developed countries. The increase in the frequency of allergic diseases is thought to be primarily due to environmental changes related to a westernized lifestyle, which affects the commensal microbes in the human body. The human gut is the largest organ colonized by bacteria and contains more than 1000 bacterial species, called the “gut microbiota.” The recent development of sequencing technology has enabled researchers to genetically investigate and clarify the diversity of all species of commensal microbes. The collective genomes of commensal microbes are together called the “microbiome.” Although the detailed mechanisms remain unclear, it has been proposed that the microbiota/microbiome, especially that in the gut, impacts the systemic immunity and metabolism, thus affecting the development of various immunological diseases, including allergies. In this review, we summarize the recent findings regarding the importance of the microbiome/microbiota in the development of allergic diseases and also the results of interventional studies using probiotics or prebiotics to prevent allergies. © 2014, Springer-Verlag Berlin Heidelberg.

PURPOSE:: We investigated whether scleral imbrication combined with pars plana vitrectomy without internal limiting membrane peeling would be effective in treating eyes with myopic macular schisis. METHODS:: In this retrospective, interventional case series, 8 eyes of 8 patients with myopic retinoschisis without a macular hole were studied. Scleral imbrication was done with 6-mm-wide mattress sutures placed at the temporal quadrants. Pars plana vitrectomy and removal of the vitreous cortex were performed, but the internal limiting membrane was not removed. The best-corrected visual acuity was measured, and the retinal morphology was determined by spectral-domain optical coherence tomography before and at 6 and 12 months postoperatively. RESULTS:: The mean age of the subjects was 67.1 years. The best-corrected visual acuity improved from 0.71 ± 0.25 to 0.36 ± 0.19 logarithm of the minimum angle of resolution units (Snellen equivalent: from 20/100 to 20/50) at 12 months (P = 0.028). The axial length was shortened from 29.5 ± 1.7 to 28.5 ± 2.5 at 12 months (P = 0.012). The central foveal thickness decreased from 540 ± 171 μm to 170 ± 85 μm at 12 months (P = 0.012). In the 6 macular-detached eyes, 5 eyes (83%) had a complete resolution. The curvature of posterior eye wall was flatter at 12 months (P = 0.049). No retinal complications were observed. CONCLUSION:: Scleral imbrication combined with pars plana vitrectomy can be an effective method of treating myopic schisis. © 2016 by Ophthalmic Communications Society, Inc.

Hashimoto K.,Chiba University
Nihon Arukōru Yakubutsu Igakkai zasshi = Japanese journal of alcohol studies & drug dependence | Year: 2013

Accumulating evidence suggests a role of inflammation in the pathophysiology of a number of neuropsychiatric diseases. The second generation antibiotic drug minocycline has potent neuroprotective and anti-inflammatory effects. We reported that minocycline could attenuate behavioral abnormalities and dopaminergic neurotoxicity in mice after administration of methamphetamine or 3,4-methylenedioxymethamphetamine (MDMA). Furthermore, we reported that minocycline was effective in the animal models of schizophrenia. Moreover, a double-blind, placebo-control, cross-over study showed that minocycline was effective in the rewarding effects in healthy human subjects. In this article, we would like to discuss minocycline as a potential therapeutic drug for methamphetamine-related disorders.

We have prepared and characterized two novel Lewis acidic ionic liquids, 4,5-dibromo- and 4,5-diiodo-1-butyl-3-methylimidazolium trifluoromethanesulfonates, using differential scanning calorimetry and single-crystal X-ray analysis. The effect of the halogen species on the phase transition behaviour and the cation-anion interacting geometry was investigated. The minor difference in chemical structure strongly affects the melting point, glass transition temperature and crystal structure because of the different halogen-bonding strength and linearity between C-Br⋯O and C-I⋯O. Both the salts melt above room temperature, but the fused salts show glass-forming property and poor crystallizability. © 2010 Elsevier Masson SAS. All rights reserved.

Shimobaba T.,Chiba University | Matsushima K.,Kansai University | Kakue T.,Chiba University | Masuda N.,Chiba University | Ito T.,Chiba University
Optics Letters | Year: 2012

The angular spectrum method (ASM) calculates diffraction calculation in a high numerical aperture, unlike Fresnel diffraction. However, this method does not allow us to calculate at different sampling rates on source and destination planes. In this Letter, we propose a scaled ASM that calculates diffraction at different sampling rates on source and destination planes using the nonuniform fast Fourier transform. © 2012 Optical Society of America.

Hao L.,Chiba University | Lu Y.,Chiba University | Asanuma H.,Chiba University | Guo J.,Chiba University
Journal of Materials Processing Technology | Year: 2012

Mechanical coating technique (MCT) was used to fabricate Fe thin films on alumina balls. The influence of the processing parameters including the milling atmosphere and the rotation speed of planetary ball mill on the formation of the thin films was investigated. The results of SEM and EDS showed that Fe particles reacted with oxygen in the air atmosphere and the formed ferroferric oxide hindered the formation of the thin films. Rotation speed also had great influence. Continuous Fe thin films with an average thickness of about 10 μm were formed during the milling operation at 300 rpm. However, they could not be formed at 200 and 400 rpm. Furthermore, the evolution of the thin films was also studied and analyzed. An evolution model was proposed to describe it. According to the model, the evolution fell into nucleation, growth of nuclei, formation of thin films and exfoliation. It was considered that mechanical interlocking played an important role in the formation of the thin films. © 2012 Elsevier B.V.

Yoshino I.,Chiba University
Japanese Journal of Cancer and Chemotherapy | Year: 2014

Cancer chemotherapy-induced anemia (CIA) is observed in approximately 70% of patients treated with cytotoxic chemotherapy. The hemoglobin concentration in the peripheral blood is ≤ 10 g/dL in 40% of these patients, and ≤ 8 g/dL in 23% of these patients. Red blood cell transfusion is performed in 16% of these patients. Since erythropoiesis-stimulating agents (ESA) are not approved in Japan, blood transfusion is the only choice of treatment for CIA. In Northwestern countries, ESA have been utilized for the treatment of CIA for > 20 years. Recently, however, the use of ESA has become regulated towing to concerns about the potential life-shortening effects, although ESA are still the treatment of choice for CIA. In this paper, the characteristics of CIA in Japan and the underlying issues have been discussed.

Tabata M.,Sakakibara Heart Institute | Shibayama K.,Sakakibara Heart Institute | Watanabe H.,Sakakibara Heart Institute | Sato Y.,Chiba University | And 2 more authors.
Journal of Thoracic and Cardiovascular Surgery | Year: 2014

Objective: A supra-annular aortic valve prosthesis is often used for aortic valve replacement in patients with a small aortic annulus. However, which suture technique provides the best valve performance has not been studied. We aimed to compare valve performance between 2 different suture techniques. Methods: We reviewed 152 patients undergoing aortic valve replacement with a 19- or 21-mm Carpentier-Edwards Perimount Magna aortic bioprosthesis (Edwards Lifesciences, Irvine, Calif) between June 2008 and December 2010. Simple interrupted sutures were used in 102 patients (group A, 19-mm prosthesis in 47 patients and 21-mm prosthesis in 55 patients), and noneverting mattress sutures were used in 50 patients (group B, 19-mm prosthesis in 20 patients and 21-mm prosthesis in 30 patients). Transthoracic echocardiograms were performed at baseline and before discharge in all patients and 1 year after surgery in 141 patients. We compared the effective orifice area and incidence of prosthesis-patient mismatch (effective orifice area index <0.85 cm 2/m2) between 2 groups. Results: The mean postoperative effective orifice areas were 1.41 ± 0.32 cm2/m2 in group A and 1.30 ± 0.28 cm2/m2 in group B (P =.025). The incidence of prosthesis-patient mismatch was 29% in group A and 56% in group B (P =.002). A multivariate analysis has shown that simple interrupted suturing is a negative predictor of prosthesis-patient mismatch (odds ratio, 0.33; 95% confidence interval, 0.13-0.83; P =.018). At 1 year, the incidence of prosthesis-patient mismatch was 27% in group A and 47% in group B (P =.023). Conclusions: Simple interrupted sutures provide larger effective orifice areas and reduce the incidence of prosthesis-patient mismatch after aortic valve replacement with a small supra-annular bioprosthesis. This suture technique is preferred in those patients to maximize valve performance. Copyright © 2014 by The American Association for Thoracic Surgery.

Wakaiki M.,Chiba University | Yamamoto Y.,Kyoto University
IEEE Transactions on Automatic Control | Year: 2016

This paper addresses the problem of designing time-varying quantizers for the stabilization of switched linear systems with quantized output and switching delays. The detection delays of switches are assumed to be time-varying but bounded, and the dwell time of the switching signal is assumed to be larger than the maximum delay. Given a switching controller, we analyze reachable sets of the closed-loop state by using a common Lyapunov function and then construct a quantizer that guarantees asymptotic stability. A sufficient condition for the existence of such a quantizer is characterized by the maximum switching delay and the dwell time. © 1963-2012 IEEE.

Troponin is well known as a Ca 2+-dependent regulator of striated muscle contraction and it has been generally accepted that troponin functions as an inhibitor of muscle contraction or actin-myosin interaction at low Ca 2+ concentrations, and Ca 2+ at higher concentrations removes the inhibitory action of troponin. Recently, however, troponin became detectable in non-striated muscles of several invertebrates and in addition, unique troponin that functions as a Ca 2+-dependent activator of muscle contraction has been detected in protochordate animals, although troponin in vertebrate striated muscle is known as an inhibitor of the contraction in the absence of a Ca 2+. Further studies on troponin in invertebrate muscle, especially in non-striated muscle, would provide new insight into the evolution of regulatory systems for muscle contraction and diverse function of troponin and related proteins. The methodology used for preparation and characterization of functional properties of protochordate striated and smooth muscles will be helpful for further studies of troponin in other invertebrate animals. © 2011.

Chiba T.,Chiba University | Iwama A.,Chiba University | Yokosuka O.,Chiba University
Hepatology Research | Year: 2016

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third most frequent cause of cancer-related death worldwide. Despite advances in its diagnosis and treatment, the prognosis of patients with advanced HCC remains unfavorable. Recent advances in stem cell biology and associated technologies have enabled the identification of minor components of tumorigenic cells, termed cancer stem cells (CSC) or tumor-initiating cells, in cancers such as HCC. Furthermore, because CSC play a central role in tumor development, metastasis and recurrence, they are considered to be a therapeutic target in cancer treatment. Hepatic CSC have been successfully identified using functional and cell surface markers. The analysis of purified hepatic CSC has revealed the molecular machinery and signaling pathways involved in their maintenance. In addition, epigenetic transcriptional regulation has been shown to be important in the development and maintenance of CSC. Although inhibitors of CSC show promise as CSC-targeting drugs, novel therapeutic approaches for the eradication of CSC are yet to be established. In this review, we describe recent progress in hepatic CSC research and provide a perspective on the available therapeutic approaches based on stem cell biology. © 2016 John Wiley & Sons, Ltd.

Tabata M.,Chiba University | Moriyama K.,Chiba University | Togo H.,Chiba University
European Journal of Organic Chemistry | Year: 2014

On the basis of studies of the transformation of benzylic bromides into the corresponding aromatic aldehydes by treatment with N-methylmorpholine N-oxide, various methylarenes were treated either with DBDMH in the presence of AIBN in acetonitrile at reflux (Method A) or with NBS in CCl4 under irradiation with a tungsten lamp at 30 °C (Method B), followed by treatment with N-methylmorpholine N-oxide to provide aromatic aldehydes in good yields. These methods could be adopted in one-pot transformations of methylarenes into aromatic aldehydes under conditions free of less toxic reagents and transition metals. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ohba T.,Chiba University | Kanoh H.,Chiba University
Journal of Physical Chemistry Letters | Year: 2012

Graphene has become a primary material in nanotechnology and has a wide range of potential applications in electronics. Fabricated graphenes are generally nanosized and composed of stacked graphene layers. The edges of nanographenes predominantly influence the chemical and physical properties because nanographene layers have a large number of edges. We demonstrated the edge effects of nanographenes and discrimination against basal planes in molecular adsorption using grand canonical Monte Carlo simulations. The edge sites of nanographene layers have relatively strong Coulombic interactions as a result of the partial charges at the edges, but the basal planes rarely have Coulombic interactions. CO 2 and N 2 prefer to be adsorbed on the edge sites and basal planes, respectively. As a result of these different preferences, the separation ability of CO 2 is higher than that of N 2 in the low-pressure region, thereby offering selective adsorptions, reactions, and separations on nanographene edges. © 2012 American Chemical Society.

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

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

Kawagoe Y.,Chiba University | Moriyama K.,Chiba University | Togo H.,Chiba University
European Journal of Organic Chemistry | Year: 2014

Various methylarenes were transformed into the corresponding aromatic nitriles in good to moderate yields by the treatment with aq. HBr and aq. H 2O2, followed by reaction with molecular iodine and aq. ammonia in a one-pot procedure. The present reaction is a useful, practical, transition-metal-free, and organic-reagent-free method for the preparation of aromatic nitriles from methylarenes. Various methylarenes were treated with aq. HBr and aq. H2O2 under warming conditions and/or irradiation conditions, followed by the reaction with molecular iodine and aq. ammonia, to provide the corresponding aromatic nitriles, in a one-pot procedure. The present reaction was carried out under metal-free and organic-reagent-free conditions. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Matui H.,Chiba University
Communications in Mathematical Physics | Year: 2010

We consider ℤ-actions (single automorphisms) on a unital simple AH algebra with real rank zero and slow dimension growth and show that the uniform outerness implies the Rohlin property under some technical assumptions. Moreover, two ℤ-actions with the Rohlin property on such a C*-algebra are shown to be cocycle conjugate if they are asymptotically unitarily equivalent. We also prove that locally approximately inner and uniformly outer ℤ2actions on a unital simple AF algebra with a unique trace have the Rohlin property and classify them up to cocycle conjugacy employing the OrderExt group as classification invariants. © 2009 Springer-Verlag.

Tsuboi A.,Chiba University | Nakamura K.,Chiba University | Kobayashi N.,Chiba University
Advanced Materials | Year: 2013

The first localized surface plasmon resonance (LSPR)-based multicolor electrochromic device with five reversible optical states is demonstrated. In this device, the size of deposited silver nanoparticles is electrochemically controlled by using a voltage-step method in which two different voltages are applied successively. The electrochemically size-controlled silver nanoparticles enable a reversible multiple-color change by a shift of the LSPR band. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sasamoto T.,Chiba University | Spohn H.,TU Munich
Journal of Statistical Physics | Year: 2010

We consider the asymmetric simple exclusion process in one dimension with weak asymmetry (WASEP) and 0-1 step initial condition. Our interest are the fluctuations of the time-integrated particle current at some prescribed spatial location. One expects a crossover from Gaussian to Tracy-Widom distributed fluctuations. The appropriate crossover scale is an asymmetry of order √ε, times of order ε-2, and a spatial location of order ε-3/2. For this parameter window we obtain the limiting distribution function of the integrated current in terms of an integral over the difference of two Fredholm determinants. For large times, on the scale ε-2, this distribution function converges to the one of Tracy-Widom. © 2010 Springer Science+Business Media, LLC.

Takanashi K.,Chiba University | Yamaguchi A.,Chiba University
Biochemical and Biophysical Research Communications | Year: 2014

Protein aggregate/inclusion is one of hallmarks for neurodegenerative disorders including amyotrophic lateral sclerosis (ALS). FUS/TLS, one of causative genes for familial ALS, encodes a multifunctional DNA/RNA binding protein predominantly localized in the nucleus. C-terminal mutations in FUS/TLS cause the retention and the inclusion of FUS/TLS mutants in the cytoplasm. In the present study, we examined the effects of ALS-linked FUS mutants on ALS-associated RNA binding proteins and RNA granules. FUS C-terminal mutants were diffusely mislocalized in the cytoplasm as small granules in transiently transfected SH-SY5Y cells, whereas large aggregates were spontaneously formed in ∼10% of those cells. hnRNP A1, hnRNP A2, and SMN1 as well as FUS wild type were assembled into stress granules under stress conditions, and these were also recruited to FUS mutant-derived spontaneous aggregates in the cytoplasm. These aggregates stalled poly(A) mRNAs and sequestered SMN1 in the detergent insoluble fraction, which also reduced the number of nuclear oligo(dT)-positive foci (speckles) in FISH (fluorescence in situ hybridization) assay. In addition, the number of P-bodies was decreased in cells harboring cytoplasmic granules of FUS P525L. These findings raise the possibility that ALS-linked C-terminal FUS mutants could sequester a variety of RNA binding proteins and mRNAs in the cytoplasmic aggregates, which could disrupt various aspects of RNA equilibrium and biogenesis. © 2014 Elsevier Inc. All rights reserved.

Ohba T.,Chiba University
Journal of Physical Chemistry C | Year: 2015

Knowledge of the dynamic properties of electrolyte solutions during charge and discharge cycles is crucial for understanding and developing electric energy devices. Molecular dynamics simulations of aqueous NaCl solution in nanopores between charged graphene layers were performed to assess the dynamical mechanism of ion transfer. Ions moved to the oppositely charged graphene layer according to the strength of their partial charges. The ion hydration numbers increased during ion transfer, suggesting quick rearrangement of water molecules around the ions to form a hydration shell. The extent of hydrogen bonding also increased during ion transfer. Water molecules participating in ion transfer hydrated the ion and simultaneously maintained hydrogen bonding, supporting a quick ion transfer mechanism during charge and discharge cycles. © 2015 American Chemical Society.

Ito K.,Chiba University
2015 9th European Conference on Antennas and Propagation, EuCAP 2015 | Year: 2015

Body-centric wireless communications (BCWCs) have recently become an active area of research because of many applications such as medical care systems, identification systems and entertainment. In this review paper, a compact dual-mode antenna for on-body and off-body communications is presented. In on-body mode, the antenna performs as an electrode which generates electric field distribution at 10 MHz. Therefore, significant low-power consumption can be realized for on-body communications. In off-body mode, the antenna radiates at the 2.45 GHz ISM band to communicate with an external device. © 2015 EurAAP.

Nishino T.,Chiyoda Corporation | Osawa M.,Chiba University | Iwama A.,Chiba University
Expert Opinion on Biological Therapy | Year: 2012

Introduction: Hematopoietic stem cells (HSCs) are defined by their capacity to self-renew and to differentiate into all blood cell lineages, and are currently the foundation of HSC transplantation therapy. A variety of methods have recently been explored to find a way to expand hematopoietic stem and progenitor cells (HSCs/PCs) ex vivo in order to improve the efficiency and outcome of HSC transplantation. Areas covered: Recent studies of HSCs/PCs have led to the development of new ways to detect and purify HSCs/PCs and have also revealed several intrinsic and extrinsic factors that control the molecular signals fundamental to self-renewal and differentiation of HSCs. These findings have provided new approaches for expanding HSCs/PCs ex vivo utilizing protein factors and small-molecule compounds (SMCs) and have also demonstrated promising outcomes in clinical trials. Expert opinion: Although further technical innovation is still needed, elucidation of the whole picture of signaling pathways critical to HSCs/PCs and manipulation of such pathways by SMCs could establish efficient, cost-effective, riskless and robust methods for ex vivo expansion of HSCs/PCs. With these efforts, more sophisticated HSC transplantation would be possible in the near future. © 2012 Informa UK, Ltd.

Eguchi N.,Chiba University
Electronic Proceedings in Theoretical Computer Science, EPTCS | Year: 2015

The general form of safe recursion (or ramified recurrence) can be expressed by an infinite graph rewrite system including unfolding graph rewrite rules introduced by Dal Lago, Martini and Zorzi, in which the size of every normal form by innermost rewriting is polynomially bounded. Every unfolding graph rewrite rule is precedence terminating in the sense of Middeldorp, Ohsaki and Zantema. Although precedence terminating infinite rewrite systems cover all the primitive recursive functions, in this paper we consider graph rewrite systems precedence terminating with argument separation, which form a subclass of precedence terminating graph rewrite systems. We show that for any precedence terminating infinite graph rewrite system g with a specific argument separation, both the runtime complexity of g and the size of every normal form in g can be polynomially bounded. As a corollary, we obtain an alternative proof of the original result by Dal Lago et al. © Naohi Eguchi This work is licensed under the Creative Commons Attribution License.

Catalytic asymmetric Friedel-Crafts reaction of indoles with nitroalkenes was catalyzed by the stereochemically tunable bis(oxazolidine)pyridine (PyBodine)-Cu(OTf)2 complex. Using the PyBodine(Val)-Cu(OTf) 2 catalyst gave the Friedel-Crafts Âadducts with highly enantioselective manner. For the 1,4-bis[(E)-2-nitrovinyl]benzene, the reaction proceeded in a meso-trick manner to give the chiral double Friedel-Crafts adduct with 97% enantiomeric excess. © Georg Thieme Verlag Stuttgart New York.

Yamada Y.,Chiba University | Kim J.,Chiba University | Matsuo S.,Chiba University | Sato S.,Chiba University
Carbon | Year: 2014

X-ray photoelectron spectroscopy (XPS) has been commonly used to determine the nitrogen-containing functional groups of graphene. However, reported assignments of C1s shifts of nitrogen-containing functional groups are unclear. Most works discuss peak shifts of only N1s spectra and C1s shifts and the full width at half maximum (FWHM) are excluded. Thus, peak shifts and FWHMs of C1s and N1s XPS spectra of graphene with nitrogen-containing functional groups such as pyridinic, phenanthroline-like, sp2C-NH2, sp 3C-NH2, pyrrolic, imine, pyridazine-like, pyrazole-like, sp2C-CN, sp3C-CN, and valley quaternary nitrogen (Q-N) on edges and sp3C-NH2, center amine, and center Q-N in the basal plane were simulated using density functional theory calculation. Main peaks of C1s spectra were shifted positively and negatively by the electron-withdrawing and electron-donating functional groups, respectively. FWHMs of the main peaks of C1s spectra were influenced by mainly electron-withdrawing functional groups on edges and most functional groups in the basal plane. Sp2C-NH2 on zigzag edges is suggested as a reference functional group to adjust the N1s spectra because influence of the functional group on the shift of main peak and the FWHM of C1s spectrum was small. © 2013 Elsevier Ltd. All rights reserved.

Fausch K.D.,Colorado State University | Baxter C.V.,Idaho State University | Murakami M.,Hokkaido University | Murakami M.,Chiba University
Freshwater Biology | Year: 2010

Streams are highly connected to their landscapes and so are easily altered by multiple stressors that affect both uplands and riparian zones, and the streams themselves. These include dams and diversions, channelisation, deforestation, water pollution, biological invasions and climate change. 2. We review research conducted in Hokkaido Island, northern Japan, which measured the effects of many of these stressors on both stream food webs and fluxes of invertebrates to and from the riparian zone that feed aquatic and terrestrial consumers. About half the energy that sustains fish falls directly into streams as terrestrial invertebrates, and a quarter of the energy needs for riparian birds is supplied by adult aquatic insects emerging from the stream. 3. Single stressors in these Hokkaido streams, including deforestation, channelisation, erosion-control dams, biological invasions and climate change, have drastic effects on stream food webs, the fishes they support and riparian predators (spiders, birds, and bats). Most stressors caused 30-90% declines in foraging, growth, or abundance of aquatic or terrestrial predators. Indirect effects of stressors also cascaded throughout stream food webs and across the aquatic-terrestrial boundary. 4. Effects of individual stressors were largely concordant across spatial scale, through time during years of different productivity and among different food web components. 5. Two studies of multiple stressors revealed that each stressor alone reduced food web components like abundance of stream benthos or riparian spiders to low levels (35-83% reduction; mean 59%), beyond which an additional stressor had little effect. Synergism and antagonism are less relevant when individual stressors have such large effects. 6. Thematic implications: small streams in Hokkaido are highly sensitive to many individual stressors and have little resistance or resilience to their effects. Moreover, each stressor alone can reduce biota strongly, indicating that restoration will need to consider all simultaneously to protect biotic diversity. © 2010 Blackwell Publishing Ltd.

Vargas M.A.,Buck Institute for Age Research | Luo N.,Buck Institute for Age Research | Yamaguchi A.,Chiba University | Kapahi P.,Buck Institute for Age Research
Current Biology | Year: 2010

Balancing intake of diverse nutrients is important for organismal growth, reproduction, and survival. A shift in an organism's optimal diet due to changes in nutritional requirements after developmental or environmental changes is referred to as dietary switch and has been observed in several species [1]. Here we demonstrate that female Drosophila melanogaster also undergo a dietary switch following mating that leads to an increased preference for yeast, the major source of protein in their diet. We also demonstrate that S6 kinase (S6K) and serotonin production are involved in the postmating dietary switch. To further investigate the ability of D. melanogaster to balance nutrient intake, we examined the dietary preferences of adult flies following deprivation of yeast or sucrose. We observe that following conditioning on a diet deficient in either carbohydrates or yeast, D. melanogaster show a strong preference for the deficient nutrient. Furthermore, flies with activated dS6K or flies fed a serotonin precursor exhibit enhanced preference for yeast in this assay. Our results suggest that TOR signaling and serotonin may play an important role in maintaining nutrient balance in D. melanogaster. These studies may contribute to our understanding of metabolic disorders such as obesity and diabetes [2]. © 2010 Elsevier Ltd. All rights reserved.

Sasamoto T.,Chiba University | Spohn H.,TU Munich
Journal of Statistical Mechanics: Theory and Experiment | Year: 2010

We explain the exact solution of the 1 + 1-dimensional Kardar-Parisi-Zhang equation with sharp wedge initial conditions. Thereby it is confirmed that the continuum model belongs to the KPZ universality class, not only as regards scaling exponents but also as regards the full probability distribution of the height in the long time limit. © 2010 IOP Publishing Ltd and SISSA.

Touge T.,Chiba University | Touge T.,Takasago International Corporation | Arai T.,Chiba University
Journal of the American Chemical Society | Year: 2016

Protecting-group-free transformation is a challenging and important issue in atom-economical organic synthesis. The η6-arene/N-Me-sulfonyldiamine-Ru(II)-BF4 complex-catalyzed asymmetric hydrogenation of 2-substituted unprotected indoles in weakly acidic hexafluoroisopropanol gives optically active indoline compounds with up to >99% ee. Under mild reaction media, halogen atoms and synthetically important protecting groups (e.g., silyl ether, acetal, benzyl ether, and ester) on indoles are maintained, which is advantageous for the synthesis of further complex indoline molecules. © 2016 American Chemical Society.

Yonezawa N.,Chiba University
Advances in Experimental Medicine and Biology | Year: 2014

The zona pellucida (ZP), which surrounds the mammalian oocyte, functions in various aspects of fertilization. The ZP consists of three or four glycoproteins, which are derived from transmembrane proteins that lack the ability to selfassemble. Following posttranslational processing at specific sites, ectodomains of ZP precursor proteins are released from the membrane and begin to form a matrix. Glycosylational modification is thought to be involved in speciesselective sperm recognition by ZP proteins. However, in mice, the supramolecular structure of the zona matrix is also important in sperm recognition. One ZP protein, ZP2, is processed at a specific site upon fertilization by ovastacin, which is released from cortical granules inside the oocyte. This phenomenon is involved in the block to polyspermy. The proteolysis of ubiquitinated ZP proteins by a sperm-associated proteasome is involved in penetration of the zona matrix by sperm, at least in the pigs. Thus, the posttranslational modification of ZP proteins is closely tied to ZP formation and the regulation of sperm–oocyte interactions. © Springer Science+Business Media New York 2014.

Nohata N.,Chiba University | Hanazawa T.,Chiba University | Enokida H.,Kagoshima University | Seki N.,Chiba University
Oncotarget | Year: 2012

MicroRNAs (miRNAs) are endogenous short non-coding RNA molecules that regulate gene expression by repressing translation or cleaving RNA transcripts in a sequence-specific manner. A growing body of evidence suggests that miRNAs are aberrantly expressed in many human cancers and that they play significant roles in the initiation, development and metastasis of human cancers. Genome-wide miRNA expression signatures provide information on the aberrant expression of miRNAs in cancers rapidly and precisely. Recently, studies from our group and others revealed that microRNA-1 (miR-1), microRNA-133a (miR-133a), microRNA-133b (miR-133b) and microRNA-206 (miR-206) are frequently downregulated in various types of cancers. Interestingly, miR-1-1/miR-133a-2, miR-1-2/miR-133a-1, and miR-206/miR-133b form homologous clusters in three different chromosomal regions of the human genome - 20q13.33, 18q11.2 and 6p12.2, respectively. Here we review recent findings on the aberrant expression and functional significance of the miR-1/miR-133a and miR-206/miR-133b clusters in human cancers. © Nohata et al.

Ushijima S.,Chiba University | Moriyama K.,Chiba University | Togo H.,Chiba University
Tetrahedron | Year: 2012

Various electron-rich aromatics could be efficiently transformed into the corresponding aromatic nitriles in good to moderate yields by treatment with DMF and POCl 3, followed by the reaction with molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH) in aq NH 3. Some of less reactive aromatics, such as anisole, 1,2-dimethoxybenzene, 1,4-dimethoxybenzene, and mesityrene, could be also transformed into the corresponding aromatic nitriles in good to moderate yields using N-methylformanilide and O(POCl 2) 2, followed by the reaction with molecular iodine in aq NH 3. Moreover, propiophenone derivatives could be successfully transformed into the corresponding β-chlorocinnamonitriles by the reaction with DMF and POCl 3, followed by the reaction with molecular iodine and aq NH 3. These reactions are novel metal-free one-pot methods for the preparation of aromatic nitriles from electron-rich aromatics and β-chlorocinnamonitriles from propiophenones. © 2012 Elsevier Ltd. All rights reserved.

Dohi S.,Chiba University | Moriyama K.,Chiba University | Togo H.,Chiba University
Tetrahedron | Year: 2012

Various diaryl ketones, alkyl aryl ketones, and dialkyl ketones were efficiently prepared in good yields by the reactions of the Grignard reagents derived from aryl or alkyl bromides, followed by the reactions with aromatic or aliphatic aldehydes and the subsequent treatment with 1,3-diiodo-5,5- dimethylhydantoin and K 2CO 3, in a one-pot method. The same treatment of aromatic bromides bearing electron-withdrawing groups, such as ester, nitrile, ketone, and nitro groups with i-PrMgCl·LiCl or PhMgCl instead of Mg, also provided the corresponding diaryl and alkyl aryl ketones in good yields. The above methods are simple and practical transition-metal-free methods for the preparation of various diaryl ketones and alkyl aryl ketones bearing electron-rich aromatic groups and electron-deficient aromatic groups, as well as dialkyl ketones. © 2012 Elsevier Ltd. All rights reserved.

Tawara M.,Chiba University
Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C | Year: 2012

Recently, Quad-rotor type helicopters which are representative of Multi-rotor type helicopters have been extensively developed over the world. The Multi-rotors are expected to replace Single-rotor type helicopters as an industrial helicopter because of their simplicity of the structure and good maintainability. In this paper, we focused on the operation problems of previous industrial helicopters and applied the Multi-rotors by a generalized design method. The generalization of the design method is performed considering variation of requirements of airframe specifications. In addition, we considered using commercial components rather than customized components in each process, so we achieved cost reduction compared with previous study. At first, we introduce the required specifications of a small pesticide application in this study and present the airframe design method. And then, we tuned parameters with presented simulation model and implement a multi-rotor type helicopter following the design method. Finally, we show the flight result and present the effectiveness of the design method. © 2012 The Japan Society of Mechanical Engineers.

Kitagawa M.,Chiba University
Journal of Biochemistry | Year: 2015

Notch signalling plays pivotal roles in development and homeostasis of all metazoan species. Notch is a receptor molecule that directly translates information of cell-cell contact to gene expression in the nucleus. Mastermind is a conserved and essential nuclear factor that supports the activity of Notch. Here, the past and current studies of the interplay between these factors are reviewed. © 2015 The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Shimobaba T.,Chiba University | Nakayama H.,Chiba University | Masuda N.,Chiba University | Ito T.,Chiba University
Optics Express | Year: 2010

A rapid calculation method of Fresnel computer-generatedhologram (CGH) using look-up table and wavefront-recording plane (WRP) methods toward three-dimensional (3D) display is presented. The method consists of two steps: the first step is the calculation of a WRP that is placed between a 3D object and a CGH. In the second step, we obtain an amplitude-type or phase-type CGH to execute diffraction calculation from the WRP to the CGH. The first step of the previous WRP method was difficult to calculate in real-time due to the calculation cost. In this paper, in order to obtain greater acceleration, we apply a look-up table method to the first step. In addition, we use a graphics processing unit in the second step. The total computational complexity is dramatically reduced in comparison with conventional CGH calculations. We show optical reconstructions from a 2,048 × 2,048 phase-type CGH generated by about 3 × 104 object points over 10 frames per second. © 2010 Optical Society of America.

Ichikawa M.,Chiba University | Masakura Y.,Tokyo Polytechnic University
Attention, Perception, and Psychophysics | Year: 2010

In the present study, we investigated how observers' control of stimulus change affects temporal and spatial aspects of visual perception. We compared the illusory flash-lag effects for automatic movement of the stimulus with stimulus movement that was controlled by the observers' active manipulation of a computer mouse (Experiments 1, 2, and 5), a keyboard (Experiment 3), or a trackball (Experiment 4). We found that the flash-lag effect was significantly reduced when the observer was familiar with the directional relationship between the mouse movement and stimulus movement on a front parallel display (Experiments 1 and 2) and that, although the unfamiliar directional relationship between the mouse movement and stimulus movement increased the flash-lag effect at the beginning of the experimental session, the repetitive observation with the same unfamiliar directional relationship reduced the flash-lag effect (Experiment 5). We found no consistent reduction of the flash-lag effect with the use of a keyboard or a trackball (Experiments 3 and 4). These results suggest that the learning of a specific directional relationship between a proprioceptive signal of hand movements and a visual signal of stimulus movements is necessary for the reduction of the flash-lag effect. © 2010 The Psychonomic Society, Inc.

Switching enantioface selection of imines in the metal-catalyzed nitro-Mannich reaction was accomplished with the same enantiomer of diamine-derived bis(imidazolidine)pyridine (PyBidine) ligand. The (S,S)-PyBidine-CoCl2 complex catalyzed the nitro-Mannich reaction of N-Ts imines to give S-enriched adducts, while the Ni(OAc)2 complex using the same ligand catalyzed the nitro-Mannich reaction of N-Boc imines in an R-stereoselective manner. © Georg Thieme Verlag Stuttgart New York.

Ando Y.,Pharmaceuticals and Medical Devices Agency | Uyama Y.,Office of Regulatory Science Pharmaceuticals and Medical Devices Agency | Uyama Y.,Chiba University
Journal of Biopharmaceutical Statistics | Year: 2012

Multiregional clinical trials including Japanese subjects are playing a key role in new drug development in Japan. In addition to the consideration of differences in intrinsic and extrinsic ethnic factors, deciding the sample size of Japanese subjects is an important issue when a multiregional clinical trial is intended to be used for Japanese submission. Accumulated experience suggests that there are several points to consider, such as the basic principles described in the guidance document, drug development strategy, trial phase, and disease background. The difficulty of interpreting the results of Japanese trials should also be considered. © 2012 Taylor and Francis Group, LLC.

Nagase A.,Chiba University | Dunnett N.,University of Sheffield
Landscape and Urban Planning | Year: 2012

Increased stormwater runoff from impervious surfaces is a major concern in urban areas and green roofs are increasingly used as an innovative means of stormwater management. However, there are very few studies on how different vegetation types affect the amount of water runoff. This paper describes an experiment that investigates the influence of plant species and plant diversity on the amount of water runoff from a simulated green roof. Twelve species were selected from the three major taxonomic and functional plant groups that are commonly used for extensive green roofs (forbs, sedum and grasses). Four species were chosen from each group and planted in combinations of increasing diversity and complexity: monocultures, four-species mixtures and twelve-species mixtures. The results showed that there was a significant difference in amount of water runoff between vegetation types; grasses were the most effective for reducing water runoff, followed by forbs and sedum. It was also shown that the size and structure of plants significantly influenced the amount of water runoff. Plant species with taller height, larger diameter, and larger shoot and root biomass were more effective in reducing water runoff from simulated green roofs than plant species with shorter height, smaller diameter, and smaller shoot and root biomass. The amount of water runoff from Sedum spp. was higher than that from bare ground. Species richness did not affect the amount of water runoff in this study. © 2011 Elsevier B.V.

Diacylglycerol kinase (DGK) phosphorylates diacylglycerol (DAG) to produce phosphatidic acid (PA) and plays an important role in signal transduction by modulating the balance between these signalling lipids. To date, 10 mammalian DGK isozymes have been identified, and these isozymes are subdivided into five groups according to their structural features. The type II DGKs, consisting of δ1, δ2, η1, η2 and κ isoforms, possess a pleckstrin homology (PH) domain at their N-termini in addition to the separate catalytic region. Moreover, DGKs δ1, δ2 and η2 have a sterile α motif domain at their C-termini. Recent studies have revealed that type II DGKs play pivotal roles in a wide variety of mammalian signal transduction pathways for cell proliferation and differentiation and glucose metabolism and that the DGKs are involved in cancer, type II diabetes, seizures, hypospadias and bipolar disorder. This review summarizes the current knowledge on the properties and physiological functions of type II DGKs and their involvement in disease. © 2012 The Authors 2012. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Yamazaki S.,Japan Science and Technology Agency | Ema H.,Tokyo Medical University | Karlsson G.,Lund University | Yamaguchi T.,Japan Science and Technology Agency | And 9 more authors.
Cell | Year: 2011

Hematopoietic stem cells (HSCs) reside and self-renew in the bone marrow (BM) niche. Overall, the signaling that regulates stem cell dormancy in the HSC niche remains controversial. Here, we demonstrate that TGF-β type II receptor-deficient HSCs show low-level Smad activation and impaired long-term repopulating activity, underlining the critical role of TGF-β/Smad signaling in HSC maintenance. TGF-β is produced as a latent form by a variety of cells, so we searched for those that express activator molecules for latent TGF-β. Nonmyelinating Schwann cells in BM proved responsible for activation. These glial cells ensheathed autonomic nerves, expressed HSC niche factor genes, and were in contact with a substantial proportion of HSCs. Autonomic nerve denervation reduced the number of these active TGF-β-producing cells and led to rapid loss of HSCs from BM. We propose that glial cells are components of a BM niche and maintain HSC hibernation by regulating activation of latent TGF-β. © 2011 Elsevier Inc.

Saeki J.,Chiba University | Sekine S.,Chiba University | Horie T.,Chiba University
Biochemical Pharmacology | Year: 2011

Multidrug resistance-associated protein 2 (Mrp2) is an ATP-dependent export pump that mediates the formation of bile-salt-independent bile flow. Disruption of the canalicular localization of Mrp2, without changes in its expression, is observed in chronic liver failure and is accompanied by oxidative stress. We reported previously that Mrp2 is rapidly internalized from the canalicular membrane during acute oxidative stress induced by lipopolysaccharide (LPS) in the rat liver. A disturbance in the colocalization of Mrp2 and radixin (which crosslinks actin with interacting membrane proteins) and endocytic retrieval of Mrp2 are present in chronic liver failure. However, the C-terminal phosphorylation status of radixin (p-radixin; functional form) and its protein-protein interaction with Mrp2 were not examined in the pathological cholestatic situation. In this study, we examined whether the C-terminal phosphorylation status of radixin and its interaction with Mrp2 were affected by LPS-induced experimental liver failure with cholestasis, and whether this condition was accompanied by Mrp2 internalization in the rat liver. At 3 h after LPS treatment, the canalicular expression of Mrp2 was decreased, without variation of the other canalicular transporters. Similarly, the canalicular localization of radixin was decreased after LPS treatment. These results show that LPS treatment decreased the total amount of the active form of p-radixin and the amount of radixin that coimmunoprecipitated with Mrp2, and that LPS treatment impaired the protein-protein interaction between Mrp2 and radixin. In conclusion, LPS-induced cholestasis seems to be caused by posttranscriptional regulation of Mrp2, which is due to the disruption of its interaction with radixin and by its dephosphorylation. © 2010 Elsevier Inc.

Photocatalytic reduction of carbon dioxide to fuels using solar energy is an attractive option for simultaneously capturing this major greenhouse gas and solving the shortage of sustainable energy. Efforts to demonstrate the photocatalytic reduction of CO 2 are reviewed herein. Although the photocatalytic results depended on the reaction conditions, such as the incident/absorbing light intensity from the sun or a simulated solar light source, the performance of different systems is compared. When the reactants included CO 2 and water, it was necessary to determine whether the products were derived from CO 2 and not from impurities that accumulated on/in the catalysts as a result of washing, calcination, or pretreatment in a moist environment. Isotope labeling of 13CO 2 was effective for this evaluation using Fourier-transform infrared (FTIR) spectroscopy and mass spectrometry (MS). Comparisons are limited to reports in which the reaction route was verified spectroscopically, the C source was traced isotopically, or sufficient kinetic analyses were performed to verify the photocatalytic events. TiO 2 photocatalytically produced methane at the rate of ∼0.1μmolh -1g cat -1. In aqueous solutions, formic acid, formaldehyde, and methanol were also produced. When TiO 2 was atomically dispersed in zeolites or ordered mesoporous SiO 2 and doped with Pt, Cu, N, I, CdSe, or PbS, the methane and CO formation rates were greater, reaching 1-10μmolh -1g cat -1. As for semiconductors other than TiO 2, CdS, SiC, InNbO 4, HNb 3O 8, Bi 2WO 6, promoted NaNbO 3, and promoted Zn 2GeO 4 produced methane or methanol at rates of 1-10μmolh -1g cat -1, and promoted A IILa 4Ti 4O 15 produced CO at a rate greater than 10μmolh -1g cat -1, in addition to the historically known ZnO and GaP (formaldehyde and methanol formation). The photocatalytic reduction of CO 2 was also surveyed with hydrogen, because hydrogen can be obtained from water photosplitting by utilizing natural light. CO was formed at a rate of ∼1μmolh -1g cat -1 using TiO 2, ZrO 2, MgO, and Ga 2O 3, whereas both CO and methanol were formed at a rate of 0.1-1μmolh -1g cat -1 using layered-double hydroxides consisting of Zn, Cu, Al, and Ga. When hydrogen is used, in addition to identifying the origin of the carbon, it is critical to confirm that the products are photocatalytically formed, not thermally produced via CO 2 hydrogenation. The feasibility of the strategy involving the recycling of a sacrificial electron donor and the direct supply of protons and electrons released from water oxidation catalysts to photocatalysts for the reduction of CO 2 to fuels has been demonstrated. However, based on the results obtained to date, it is clear that the practical use of the photocatalytic reduction of CO 2 as one possible solution for global warming and the world's energy problems requires the development of more efficient photocatalysts. © 2012 Elsevier B.V..

Sakao S.,Chiba University | Tanabe N.,Chiba University | Tatsumi K.,Chiba University
American Journal of Physiology - Lung Cellular and Molecular Physiology | Year: 2010

Idiopathic pulmonary arterial hypertension (PAH) is a disabling condition characterized by PA vasoconstriction and remodeling as well as in situ thrombosis and eventual right heart failure. Idiopathic PAH occurs more frequently in females than in males. The female: male ratio is 1.64 - 3.88:1. Although endogenous sex hormones including estrogen have been suggested to account for the observed gender differences in PAH, a precise pathobiology for the gender differences remains uncertain. Recent studies demonstrated that estrogen exerts beneficial effects on the pulmonary vasculature. However, it seems to contradict the female predominance that is observed in idiopathic PAH. Moreover, Sweeney and Voelkel (Sweeney L and Voelkel NF. Eur J Med Res 14: 433-442, 2009) showed that early and long-term estrogen exposure might be correlated with an increased risk of the development of PAH. Here we ask the question: Is estrogen a friend or a foe? According to accumulating evidence, we postulate that the different effects of estrogens on different target cells could account for this paradox, i.e., estrogens may exert beneficial effects only on the increased muscularization of vessel walls, but not on phenotypically altered endothelial cells. The effects of estrogens on the pulmonary vasculature are potent and complex, yet not fully understood. A better mechanistic understanding may allow for future therapeutic interventions in patients with PAH. Copyright © 2010 the American Physiological Society.

Takaya A.,Chiba University | Erhardt M.,University of Fribourg | Karata K.,Chiba University | Winterberg K.,University of Utah | And 3 more authors.
Molecular Microbiology | Year: 2012

YdiV is an EAL-like protein that acts as a post-transcriptional, negative regulator of the flagellar master transcriptional activator complex, FlhD 4C 2, in Salmonella enterica to couple flagellar gene expression to nutrient availability. Mutants defective in ClpXP protease no longer exhibit YdiV-dependent inhibition of FlhD 4C 2-dependent transcription under moderate YdiV expression conditions. ClpXP protease degrades FlhD 4C 2, and this degradation is accelerated in the presence of YdiV. YdiV complexed with both free and DNA-bound FlhD 4C 2; and stripped FlhD 4C 2 from DNA. A L22H substitution in FlhD was isolated as insensitive to YdiV inhibition. The FlhD L22H substitution prevented the interaction of YdiV with free FlhD 4C 2 and the ability of YdiV to release FlhD 4C 2 bound to DNA. These results demonstrate that YdiV prevents FlhD 4C 2-dependent flagellar gene transcription and acts as a putative adaptor to target FlhD 4C 2 for ClpXP-dependent proteolysis. Our results suggest that YdiV is an EAL-like protein that has evolved from a dicyclic-GMP phosphodiesterase into a dual-function regulatory protein that connects flagellar gene expression to nutrient starvation. © 2012 Blackwell Publishing Ltd.

Yamaguchi M.,Chiba University | Kopecka M.,Masaryk University
Journal of Electron Microscopy | Year: 2010

Phenotypes of the two temperature-sensitive actin mutants of Saccharomyces cerevisiae act1-1 and act1-2 at permissive, restrictive and semi-restrictive temperatures were studied by freeze fracture and thin section electron microscopy, and fluorescent microscopy. In contrast to secretory mutants where accumulations of either secretory vesicles, Golgi apparatus, or endoplasmic reticulum were reported, act1-1 and act1-2 mutants revealed accumulation of all the three components, even at permissive temperature. However, more distinct accumulation of secretory organelles was evident during cultivation at the sub-restrictive temperature of 30°C. At the restrictive temperature of 37°C, many cells died, and their empty cell walls remained. Some of the few living cells showed features of apoptosis. From the present study, actin cables are concluded to be necessary for (i) correct spatial positioning and orientation of secretary pathway to the bud and septum, and (ii) vectorial movement of vesicles of the secretory pathway along the actin cables to the bud and septum. © 2009 The Author.

Hirose Y.,Chiba University
Nihon Reoroji Gakkaishi | Year: 2015

We measured electrorheological (ER) properties of suspensions of titanium dioxide/polymer composite particles using electrodes with regularly arranged fine projections. For a 10 wt% suspension, particles assembled between projections of electrodes and the yield stress became higher than the case of flat electrodes. On the other hand, the ER effect of a suspension with 30 wt% particles between pattern electrodes became weaker than between flat electrodes. From the observation of column structures of particles in a dilute (5 wt%) suspension between pattern electrodes, particles assembling between mountain sections of projections and thick columns were created. In the case of a dense (30 wt%) suspension, the space between flat and pattern electrodes was jammed with particles but several cracks were observed between valley sections on pattern electrodes. It is supposed that this difference is caused by the competition between the thick columns of mountain sections and low particle concentration regions between valley sections of pattern electrodes. © 2015 The Society of Rheology, Japan.

Stolwijk S.D.,University of Munster | Schmidt A.B.,University of Munster | Donath M.,University of Munster | Sakamoto K.,Chiba University | Kruger P.,University of Munster
Physical Review Letters | Year: 2013

We present a combined experimental and theoretical study on the unoccupied surface electronic structure of the Tl/Si(111) surface. Spin- and angle-resolved inverse-photoemission measurements with sensitivity to both the in-plane and the out-of-plane polarization direction detect a spin-orbit-split surface state, which is well described by theoretical calculations. We demonstrate that the spin polarization vector rotates from the classical in-plane Rashba polarization direction around Γ̄ to the direction perpendicular to the surface at the K̄(K̄′) points - a direct consequence of the symmetry of the 2D hexagonal system. A giant splitting in energy of about 0.6 eV is observed and attributed to the strong localization of the unoccupied surface state close to the heavy Tl atoms. This leads to completely out-of-plane spin-polarized valleys in the vicinity of the Fermi level. As the valley polarization is oppositely oriented at the K̄ and K ̄′ points, backscattering should be strongly suppressed in this system. © 2013 American Physical Society.

Yamaura K.,Chiba University | Akiyama S.,Chiba University | Ueno K.,Chiba University
Journal of Cellular Biochemistry | Year: 2012

Histamine has been regarded as an inflammatory mediator of arthritic disorders. We have previously reported that the expression of histamine H 4 receptor (H 4R) mRNA in synovial tissues was significantly higher in patients with osteoarthritis (OA) compared to those with rheumatoid arthritis. Chondrocyte hypertrophy and endochondral ossification are essential processes in pathologic disorders such as osteophyte formation during OA progression. In the present study, we examined the expression of H 4R during differentiation into hypertrophic chondrocytes in the ATDC5 cells, a widely used in vitro model of chondrogenic differentiation. Quantitative reverse transcription polymerase chain reaction showed that the levels of histidine decarboxylase and H 4R mRNA on ATDC5 cells were increased in a time-dependent manner during the culture period. By contrast, the expressions of H1R and H2R were not increased from day 7 onwards. The mRNA expression of the hypertrophic chondrocyte marker type X collagen (COL X) was increased markedly from 14 to 21. Immunocytochemical analysis indicated that H 4R staining was strongly immunoreactive on the plasma membrane of ATDC5 cells. Flow cytometry showed increased expression of H 4R and COL X protein in ATDC5 chondrocytes. Furthermore, the majority of the COL X-positive cells expressed H 4R throughout the culture period. In summary, we showed for the first time that H 4R is expressed in ATDC5 chondrocytes. Moreover, we found that most hypertrophic chondrocytes express H 4R, suggesting that this receptor might be associated with the differentiation of chondrocytes into hypertrophic cells, which are abnormally observed in joint lesions in OA. © 2011 Wiley Periodicals, Inc.

Vaisman A.,U.S. National Institutes of Health | Kuban W.,U.S. National Institutes of Health | McDonald J.P.,U.S. National Institutes of Health | Karata K.,Chiba University | And 3 more authors.
Nucleic Acids Research | Year: 2012

The active form of Escherichia coli DNA polymerase V responsible for damage-induced mutagenesis is a multiprotein complex (UmuD′2C-RecA-ATP), called pol V Mut. Optimal activity of pol V Mut in vitro is observed on an SSB-coated single-stranded circular DNA template in the presence of the β/γ complex and a transactivated RecA nucleoprotein filament, RecA*. Remarkably, under these conditions, wild-type pol V Mut efficiently incorporates ribonucleotides into DNA. A Y11A substitution in the 'steric gate' of UmuC further reduces pol V sugar selectivity and converts pol V Mut into a primer-dependent RNA polymerase that is capable of synthesizing long RNAs with a processivity comparable to that of DNA synthesis. Despite such properties, Y11A only promotes low levels of spontaneous mutagenesis in vivo. While the Y11F substitution has a minimal effect on sugar selectivity, it results in an increase in spontaneous mutagenesis. In comparison, an F10L substitution increases sugar selectivity and the overall fidelity of pol V Mut. Molecular modeling analysis reveals that the branched side-chain of L10 impinges on the benzene ring of Y11 so as to constrict its movement and as a consequence, firmly closes the steric gate, which in wild-type enzyme fails to guard against ribonucleoside triphosphates incorporation with sufficient stringency. © 2012 The Author(s).

Sasanuma Y.,Chiba University | Touge D.,Chiba University
Polymer (United Kingdom) | Year: 2014

Conformational characteristics of poly(lactide)s have been investigated by density functional theory and ab initio molecular orbital (MO) calculations and NMR experiments on model compounds. Characteristic ratios, configurational entropies, and internal energies of poly(L-lactide) and poly(DL-lactide), whose stereosequences were generated by Bernoulli and Markov stochastic processes, were calculated under the refined rotational isomeric state scheme with conformational energies and geometrical parameters derived from the MO calculations. In terms of the conformational characteristics thus revealed, we have elucidated the reason why unperturbed chain dimensions determined experimentally for poly(L-lactide) are scattered considerably and, furthermore, discussed crystallization and crystal structures of poly(L-lactide) and molecular characteristics of poly(DL-lactide) synthesized from rac-lactide with stereospecific polymerization catalysts. © 2014 Elsevier Ltd. All rights reserved.

Karata K.,U.S. National Institutes of Health | Karata K.,Chiba University | Vaisman A.,U.S. National Institutes of Health | Goodman M.F.,University of Southern California | Woodgate R.,U.S. National Institutes of Health
DNA Repair | Year: 2012

Most damage induced mutagenesis in Escherichia coli is dependent upon the UmuD'2C protein complex, which comprises DNA polymerase V (pol V). Biochemical characterization of pol V has been hindered by the fact that the enzyme is notoriously difficult to purify, largely because overproduced UmuC is insoluble. Here, we report a simple and efficient protocol for the rapid purification of milligram quantities of pol V from just 4. L of bacterial culture. Rather than over producing the UmuC protein, it was expressed at low basal levels, while UmuD'2 was expressed in trans from a high copy-number plasmid with an inducible promoter. We have also developed strategies to purify the β-clamp and γ-clamp loader free from contaminating polymerases. Using these highly purified proteins, we determined the cofactor requirements for optimal activity of pol V in vitro and found that pol V shows robust activity on an SSB-coated circular DNA template in the presence of the β/γ-complex and a RecA nucleoprotein filament (RecA*) formed in trans. This strong activity was attributed to the unexpectedly high processivity of pol V Mut (UmuD'2C{dot operator}RecA{dot operator}ATP), which was efficiently recruited to a primer terminus by SSB. © 2012.

Ohba T.,Chiba University | Chaban V.V.,University of Southern Denmark
Journal of Physical Chemistry B | Year: 2014

We report a combined experimental (X-ray diffraction) and theoretical (molecular dynamics, hybrid density functional theory) study of 1-ethyl-3-methylimidazolium chloride, [C2C1MIM][Cl], inside carbon nanotubes (CNTs). We show that despite its huge viscosity [C 2C1MIM][Cl] readily penetrates into 1-3 nm wide CNTs at slightly elevated temperatures (323-363 K). Molecular simulations were used to assign atom-atom peaks. Experimental and simulated structures of RTIL inside CNT and in bulk phase are in good agreement. We emphasize a special role of the CNT-chloride interactions in the successful adsorption of [C2C 1MIM][Cl] on the inner sidewalls of 1-3 nm carbon nanotubes. © 2014 American Chemical Society.

Yamamura N.,Chiba University | Kishimoto T.,Chiba University
Experimental and Molecular Pathology | Year: 2012

AFP-producing adenocarcinoma is a variant of adenocarcinoma with high malignancy. Production of AFP suggests enteroblastic or hepatoid differentiation of cancer cells. GATA4 is a key molecule involved in the prenatal development of the stomach and liver. GATA4 is epigenetically silenced by hypermethylation of primer region in many types of cancers including gastric cancer. The aim of this study is to investigate the expression and epigenetic regulation of GATA4 in AFP-producing adenocarcinoma. Immunohistochemical analysis revealed that GATA4 was positive in 3/8 cases of AFP-producing gastric adenocarcinomas and in 28/30 cases of common type adenocarcinomas. Epigenetic modification of GATA4 promoter region was investigated with 3 AFP-producing and 4 common-type gastric cancer cell lines. GATA4 mRNA was detected in 1/3 of AFP-producing and 2/4 of common-type gastric cancer cell lines by RT-PCR. Methylation-specific PCR revealed no GATA4 methylation in any of the AFP-producing gastric cancers, whereas methylation was consistent with GATA4 expression in the common-type gastric cancers. Chromatin immunoprecipitation assay for AFP-producing gastric cancers revealed that histones H3 and H4 were hypoacetylated in the GATA4-negative cells, while they were hyperacetylated in the GATA4-positive cells. Treatment with trichostain A, an inhibitor for histone deacetylase, induced acetylation of histones H3 and H4, and tri-methylation of lysine 4 of histone H3, which was associated with the active transcription of GATA4 in GATA4-negative AFP-producing cells. These results indicated that histone deacetylation is a silencing mechanism for GATA4 expression in AFP-producing gastric cancer cells. Differences between AFP-producing gastric cancer and common-type gastric cancer in terms of the mechanism of GATA4 regulation may be reflected in the phenotypic deviation of AFP-producing gastric cancer from common-type gastric cancer. © 2012 Elsevier Inc.

Fujii S.,RIKEN | Motohashi S.,Chiba University | Shimizu K.,RIKEN | Nakayama T.,Chiba University | And 2 more authors.
Seminars in Immunology | Year: 2010

Invariant natural killer T (iNKT) cells have adjuvant activity due to their ability to produce large amounts of IFN-γ, which activates other cells in innate and acquired systems, and orchestrates protective immunity. Based on these adjuvant mechanisms, we developed iNKT cell-targeted adjuvant therapy and carried out a phase I/IIa trial on advanced lung cancer patients. The patient group with increased numbers of IFN-γ-producing cells showed prolonged survival with a median survival time of 31.9 months. Sixty percent of the patients in this group survived for more than 2 years with only a primary treatment and without tumor progression and metastasis. © 2009 Elsevier Ltd. All rights reserved.

Yamashiro S.,Scripps Research Institute | Gokhin D.S.,Scripps Research Institute | Kimura S.,Chiba University | Nowak R.B.,Scripps Research Institute | Fowler V.M.,Scripps Research Institute
Cytoskeleton | Year: 2012

Tropomodulins are a family of four proteins (Tmods 1-4) that cap the pointed ends of actin filaments in actin cytoskeletal structures in a developmentally regulated and tissue-specific manner. Unique among capping proteins, Tmods also bind tropomyosins (TMs), which greatly enhance the actin filament pointed-end capping activity of Tmods. Tmods are defined by a TM-regulated/Pointed-End Actin Capping (TM-Cap) domain in their unstructured N-terminal portion, followed by a compact, folded Leucine-Rich Repeat/Pointed-End Actin Capping (LRR-Cap) domain. By inhibiting actin monomer association and dissociation from pointed ends, Tmods regulate actin dynamics and turnover, stabilizing actin filament lengths and cytoskeletal architecture. In this review, we summarize the genes, structural features, molecular and biochemical properties, actin regulatory mechanisms, expression patterns, and cell and tissue functions of Tmods. By understanding Tmods' functions in the context of their molecular structure, actin regulation, binding partners, and related variants (leiomodins 1-3), we can draw broad conclusions that can explain the diverse morphological and functional phenotypes that arise from Tmod perturbation experiments in vitro and in vivo. Tmod-based stabilization and organization of intracellular actin filament networks provide key insights into how the emergent properties of the actin cytoskeleton drive tissue morphogenesis and physiology. © 2012 Wiley Periodicals, Inc.

Sato S.,Chiba University | Sato F.,Chiba University | Gotoh H.,Chiba University | Yamada Y.,Chiba University
ACS Catalysis | Year: 2013

Syntheses of unsaturated alcohols in the vapor-phase catalytic dehydration of alkanediols over rare earth oxides are reviewed. CeO2 effectively catalyzes the dehydration of 1,3-butanediol to produce 3-buten-2-ol and trans-2-buten-1-ol. Heavy rare earth oxides such as Er2O3, Yb2O3, and Lu2O3 selectively catalyze the dehydration of 1,4-butanediol to produce 3-buten-1-ol. In the dehydration of 1,5-pentanediol, Yb2O3, Lu 2O3, and Sc0.5Yb1.5O3 catalysts efficiently work to produce 4-penten-1-ol. The active and selective oxides are composed of large particles with well-crystallized fluorite or bixbyite structure. Small oxide particles with poor crystallinity decrease the selectivity to unsaturated alcohols because of their dehydrogenation ability. In the reactions of different alkanediols, the reactivity of alkanediol depends on the length between the OH groups as well as on the geometry of the catalyst surface, which is affected by the distance between rare earth cations. For example, over CeO2, the reactivity order of the alkanediols is 1,3-butanediol > 1,4-butanediol > 1,5-pentanediol > 1,6-hexanediol. Quantum calculations support a probable reaction mechanism: OH groups and the H of the position-2 methylene group of 1,3-butanediol are interacted with the surface Ce4+ to form a tridentate coordination, and the abstraction of the position-2 H by Ce4+ is the initial step of 1,3-butanediol dehydration in the formation of unsaturated alcohols. © 2013 American Chemical Society.

Yonekura-Sakakibara K.,RIKEN | Fukushima A.,RIKEN | Saito K.,RIKEN | Saito K.,Chiba University
Current Opinion in Biotechnology | Year: 2013

The massive data generated by omics technologies require the power of bioinformatics, especially network analysis, for data mining and doing data-driven biology. Gene coexpression analysis, a network approach based on comprehensive gene expression data using microarrays, is becoming a standard tool for predicting gene function and elucidating the relationship between metabolic pathways. Differential and comparative gene coexpression analyses suggest a change in coexpression relationships and regulators controlling common and/or specific biological processes. In conjunction with the newly emerging genome editing technology, network analysis integrated with other omics data should pave the way for robust and practical plant metabolic engineering. © 2012 Elsevier Ltd.

Senju Y.,University of Tokyo | Itoh Y.,University of Tokyo | Takano K.,University of Tokyo | Hamada S.,University of Tokyo | And 3 more authors.
Journal of Cell Science | Year: 2011

Caveolae are flask-shaped invaginations of the plasma membrane that are associated with tumor formation, pathogen entry and muscular dystrophy, through the regulation of lipids, signal transduction and endocytosis. Caveolae are generated by the fusion of caveolin-1-containing vesicles with the plasma membrane, which then participate in endocytosis via dynamin. Proteins containing membrane-sculpting F-BAR (or EFC) domains organize the membrane in clathrin-mediated endocytosis. Here, we show that the FBAR protein PACSIN2 sculpts the plasma membrane of the caveola. The PACSIN2 F-BAR domain interacts directly with caveolin-1 by unmasking autoinhibition of PACSIN2. Furthermore, the membrane invaginations induced by the PACSIN2 F-BAR domain contained caveolin-1. Knockdown of PACSIN2 resulted in abnormal morphology of caveolin-1-associated plasma membranes, presumably as a result of decreased recruitment of dynamin-2 to caveolin-1. These results indicate that PACSIN2 mediates membrane sculpting by caveolin-1 in caveola morphology and recruits dynamin-2 for caveola fission. © 2011. Published by The Company of Biologists Ltd.

Liu W.,Chiba University | Yamazaki F.,Chiba University | Gokon H.,Tohoku University | Koshimura S.-I.,Tohoku University
Earthquake Spectra | Year: 2013

The Tohoku earthquake of 11 March 2011 caused very large tsunamis and widespread devastation. Various high-resolution satellites captured details of affected areas and were utilized in emergency response. In this study, high-resolution pre- and post-event TerraSAR-X intensity images were used to identify tsunami-flooded areas and damaged buildings. Since water surface generally shows very little backscatter, flooded areas could be extracted by the difference of backscattering coefficients between the pre- and post-event images. Impacted buildings were detected by calculating the difference and correlation coefficient within the outline of each building. The damage estimates were compared with visual interpretation results, which suggest that the overall accuracy of the proposed method for flooded areas was 80%, and for damaged buildings was 94%. Since the proposed half-automated method takes less processing time and is applicable to various cases, it is expected to provide quick and useful information in emergency management. © 2013, Earthquake Engineering Research Institute.

Yamazaki F.,Chiba University | Zavala C.,Peruvian National University of Engineering
Journal of Disaster Research | Year: 2013

This project conducts comprehensive research on earthquake and tsunami disaster mitigation in Peru in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)," sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). The project focuses on five research fields, i.e., seismic motion and geotechnical, tsunami, buildings, damage assessment, and disaster mitigation planning. Almost three years have passed since the five-year project started in March 2010. During this period, researchers in different fields from Japan and Peru collaborate to achieve the overall objectives of the project. This paper summarizes the research framework and progress of the JST-JICA project on earthquake and tsunami disaster mitigation technology in Peru.

Saito K.,RIKEN | Saito K.,Chiba University
Current Opinion in Plant Biology | Year: 2013

Phytochemical genomics is a recently emerging field, which investigates the genomic basis of the synthesis and function of phytochemicals (plant metabolites), particularly based on advanced metabolomics. The chemical diversity of the model plant Arabidopsis thaliana is larger than previously expected, and the gene-to-metabolite correlations have been elucidated mostly by an integrated analysis of transcriptomes and metabolomes. For example, most genes involved in the biosynthesis of flavonoids in Arabidopsis have been characterized by this method. A similar approach has been applied to the functional genomics for production of phytochemicals in crops and medicinal plants. Great promise is seen in metabolic quantitative loci analysis in major crops such as rice and tomato, and identification of novel genes involved in the biosynthesis of bioactive specialized metabolites in medicinal plants. © 2013 The Author.

Lubis A.M.,Chiba University | Hashima A.,Chiba University | Sato T.,Chiba University
Geophysical Journal International | Year: 2013

Most studies of afterslip distribution consider only elastic media. However, the effects of poroelastic rebound in the upper crust and viscoelastic relaxation in the asthenosphere are part of the observed post-seismic deformation. Therefore, these effects should be removed to give a more reliable and correct afterslip distribution. We developed a method for calculating an afterslip distribution in elastic, poroelastic and viscoelastic media, and we applied this method to the case of the 2007 southern Sumatra earthquake (Mw 8.5). To estimate the coseismic slip and time evolution of the afterslip distribution, we applied Akaike's Bayesian Information Criterion (ABIC) inversion method of coseismic displacement, and analysed 15 months of GPS post-seismic deformation data in 3-month observation periods. To calculate afterslip in each period, we considered not only viscoelastic responses to coseismic slip but also viscoelastic responses to afterslip in the preceding periods. We used viscoelastic model to compute postseismic deformation models every 3 months during the 15 months after the earthquake. The viscosity value for the asthenosphere layer is a crucial unknown parameter. To overcome this problem, we used a grid search method to determine the best-viscosity value, and we found that the best viscosity for the Sumatra subduction zone was 2.5 × 1018 Pas. After removing the poroelastic and viscoelastic responses, we obtained maximum afterslip of 0.5 m during the 15-month investigation (the same as maximum afterslip estimated using the elastic medium only), but the poroelastic and viscoelastic responses brought the afterslip distribution to a shallower depth than the main coseismic rupture area. The results showed that the poroelastic and viscoelastic responses added significant corrections to the afterslip distribution. Compared with the traditional method, this method improved the determination of the afterslip distribution. We conclude that consideration of poroelastic and viscoelastic behaviours is essential for calculating the afterslip distribution. We propose that these parameters should be considered to obtain more reliable and correct afterslip distribution models following earthquakes. © The Authors 2012.

Kimura E.,Chiba University | Young R.S.L.,Texas Tech University Health Sciences Center
Vision Research | Year: 2010

We show that irradiance-coding alone cannot explain the sustained pupillary constrictions evoked by chromatic and luminance variations in a stimulus. For example, stimulus modulations that decremented the contrasts in L- and M-cones as well as rods and melanopsin photoreceptors produced sustained constrictions rather than the predicted dilations. Although the sustained responses are unidirectional, we confirm that they are at least partially mediated by an L- and M-cone opponent interaction. We discuss the implications of sustained unidirectional chromatic responses in view of the function of the pupil to improve the clarity of vision. © 2010 Elsevier Ltd. All rights reserved.

Liu W.,Chiba University | Yamazaki F.,Chiba University
IEEE Geoscience and Remote Sensing Letters | Year: 2013

Significant crustal movements were caused by the 2011 Tohoku, Japan earthquake. A method for capturing the surface movements from pre- and postevent TerraSAR-X (TSX) intensity images is proposed in this letter. Because the shifts of unchanged buildings were considered as crustal movements in the two synthetic aperture radar images, we first extracted buildings from the pre- and postevent images using a segmentation approach. Then, the unchanged buildings were detected by matching the buildings in the pre- and postevent images at similar locations. Finally, the shifts were calculated by area-based matching. The method was tested on the TSX images covering the Sendai area. Compared with GPS observation records, the proposed method was found to be able to detect crustal movement at a subpixel level. © 2012 IEEE.

Sekine S.,Chiba University | Ito K.,University of Tokyo | Saeki J.,Chiba University | Horie T.,Chiba University
Biochimica et Biophysica Acta - Molecular Basis of Disease | Year: 2011

Oxidative stress is a feature of cholestatic syndrome and induces multidrug resistance-associated protein 2 (Mrp2) internalization from the canalicular membrane surface. We have previously shown that the activation of a novel protein kinase C (nPKC) by oxidative stress regulates Mrp2 internalization. The internalized Mrp2 was recycled to the canalicular surface in a protein kinase A (PKA)-dependent manner after intracellular glutathione (GSH) levels were replenished. However, the putative phosphorylation targets of these protein kinases involved in reversible Mrp2 trafficking remain unclear. In this study, we investigated the effect of changing the intrahepatic redox status on the C-terminal phosphorylation status of radixin (p-radixin), which links Mrp2 to F-actin, and the interaction of p-radixin with Mrp2 in rat hepatocytes. We detected a significant decrease in the amount of p-radixin that co-immunoprecipitated with Mrp2 after tertiary-butylhydroperoxide (t-BHP) treatment. After treatment with GSH-ethylester (GSH-EE), the phosphorylation level became the same as that of the control. A PKC and protein phosphatase (PP)-1/2A inhibitor, but not a PP-2A selective inhibitor, prevented the t-BHP-induced decrease of p-radixin and subsequent canalicular Mrp2 localization. In contrast, a PKA inhibitor affected the recovery process facilitated by GSH-EE treatment. In conclusion, the interaction of p-radixin with Mrp2 was decreased by the activation of PKC and PP-1 under oxidative stress conditions which subsequently led to Mrp2 internalization, whereas the interaction of p-radixin and Mrp2 was increased by the activation of PKA during recovery from oxidative stress. © 2011 Elsevier B.V.

Tadokoro S.,Chiba University | Okamura N.,Chiba University | Sekine Y.,Chiba University | Kanahara N.,Chiba University | And 2 more authors.
Schizophrenia Bulletin | Year: 2012

Background: Long-term treatment of schizophrenia with antipsychotics is crucial for relapse prevention, but a prolonged blockade of D2 dopamine receptors may lead to the development of supersensitivity psychosis. We investigated the chronic effects of aripiprazole (ARI) on dopamine sensitivity. Methods: We administered ARI (1.5 mg/kg/d), haloperidol (HAL; 0.75 mg/kg/d), or vehicle (VEH) via minipump for 14 days to drug-naive rats or to rats pretreated with HAL (0.75 mg/kg/d) or VEH via minipump for 14 days. On the seventh day following treatment cessation, we examined the effects of the treatment conditions on the locomotor response to methamphetamine and on striatal D2 receptor density (N 4-10/condition/experiment). Results: Chronic treatment with HAL led to significant increases in locomotor response and D2 receptor density, compared with the effects of chronic treatment with either VEH or ARI; there were no significant differences in either locomotor response or D2 density between the VEH-and ARI-treated groups. We also investigated the effects of chronic treatment with HAL, ARI, or VEH preceded by HAL or VEH treatment on locomotor response and D2 density. ANOVA analysis indicated that the rank ordering of groups for both locomotor response and D2 density was HAL-HAL > HAL-VEH > HAL-ARI > VEH-VEH. Conclusions: Chronic treatment with ARI prevents development of dopamine supersensitivity and potentially supersensitivity psychosis, suggesting that by reducing excessive sensitivity to dopamine and by stabilizing sensitivity for an extended period of time, ARI may be helpful for some patients with treatment-resistant schizophrenia. © 2012 The Author.

The purpose of the present study was to compare sinusoidal versus constant lower body negative pressure (LBNP) with reference to very mild whole-body heating. Sinusoidal LBNP has a periodic load component (PLC) and a constant load component (CLC) of orthostatic stress, whereas constant LBNP has only a CLC. We tested two sinusoidal patterns (30-s and 180-s periods with 25 mmHg amplitude) of LBNP and a constant LBNP with -25 mmHg in 12 adult male subjects. Although the CLC of all three LBNP conditions were configured with -25 mmHg, the mean arterial pressure (MAP) results showed a significantly large decrease from baseline in the 30-s period condition (P <0.01). In contrast, the other cardiovascular indices (heart rate (HR), stroke volume (SV), cardiac output (CO), basal thoracic impedance (Z(0)), total peripheral resistance (TPR), the natural logarithmic of the HF component (lnHF), and LF/HF (ln(LF/HF))) of heart rate variability (HRV) showed relatively small variations from baseline in the 30-s period condition (P <0.01). The result of the gain and phase of transfer function at the sinusoidal period of LBNP showed that the very mild whole-body heating augmented the orthostatic responses. These results revealed that the effect of the CLC of LBNP on cardiovascular adjustability was attenuated by the addition of the PLC to LBNP. Based on the results of suppressed HRV response from baseline in the 30-s period condition, we suggest that the attenuation may be caused by the suppression of the vagal responsiveness to LBNP.

Mizuta A.,High Energy Accelerator Research Organization | Mizuta A.,Chiba University | Nagataki S.,Kyoto University | Aoi J.,Kyoto University
Astrophysical Journal | Year: 2011

In this study, the light curves and spectrum of the photospheric thermal radiation from ultrarelativistic gamma-ray burst (GRB) jets are calculated using two-dimensional relativistic hydrodynamic simulations of jets from a collapsar. As the jet advances, the density around the head of the jet decreases, and its Lorentz factor reaches as high as 200 at the photosphere and 400 inside the photosphere. For an on-axis observer, the photosphere appears concave due to the low density and high beaming factor of the jet. The luminosity varies because of the abrupt change in the position of the photosphere due to the internal structure of the jet. Comparing our results with GRB090902B, the flux level of the thermal-like component is similar to our model, although the peak energy appears slightly higher (but still within a factor of two). From the comparison, we estimate that the bulk Lorentz factor of GRB 090902B is Γ ∼ 2.4 × 102(r/1012 cm), where r is the radius of the photosphere. The spectrum for an on-axis observer is harder than that for an off-axis observer. There is a time lag of a few seconds for high energy bands in the light curve. This may be the reason for the delayed onset of GeV emission seen in GRB 080916C. The spectrum below the peak energy is a power law and the index is 2.3-2.6, which is softer than that of a single temperature Planck distribution but still harder than that of the typical value of the observed spectrum. © 2011. The American Astronomical Society. All rights reserved.

Shimojo N.,Chiba University
Clinical and Experimental Allergy Reviews | Year: 2012

In Japan, loratadine, fexofenadine, cetirizine and epinastine are currently approved for paediatric use. However, none of these drugs is officially approved for use in children aged under 2 years, and therefore older second-generation antihistamines such as ketotifen and oxatomide are sometimes prescribed for these patients. Because ketotifen and oxatomide have relatively strong sedative effects, one should be cautious when using these antihistamines in young children. In fact, there are reports describing the development of West syndrome, an intractable epilepsy, in 4-month-old infants taking these drugs. Recent clinical trials in Japanese children with allergic rhinitis have shown no serious adverse effects associated with several new second-generation antihistamines, supporting previous overseas reports. New second-generation antihistamines should be approved in the near future for young children in Japan. © 2012 Blackwell Publishing Ltd.

Eisen A.,University of British Columbia | Kuwabara S.,Chiba University
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2012

In amyotrophic lateral sclerosis (ALS), hand muscle wasting preferentially affects the 'thenar (lateral) hand', including the abductor pollicis brevis (APB) and first dorsal interosseous (FDI) muscles, with relative sparing of the hypothenar muscles (the abductor digiti minimi (ADM)). This peculiar pattern of dissociated atrophy of the intrinsic hand muscles is termed the 'split hand' and is rarely seen in diseases other than ALS. The muscles involved in the split hand are innervated through the same spinal segments (C8 and T1), and FDI and ADM, which are differentially affected, are both ulnar nerve innervated. The physiological mechanisms underlying the split hand in ALS are incompletely understood but both cortical and spinal/peripheral mechanisms are probably involved. Motor potentials evoked by magnetic stimulation are significantly smaller when recorded from the thenar complex, compared with the hypothenar muscles, supporting a cortical mechanism. But peripheral axonal excitability studies have suggested that APB/FDI motor axons have more prominent persistent sodium currents than ADM axons, leading to higher axonal excitability and thereby more ready degeneration. Pincer or precision grip is vital to human hand function, and frequent use of thenar complex muscles may lead to greater oxidative stress and metabolic demands at both upper and lower motoneurons innervating the APB and FDI. The split hand is a useful diagnostic sign in early ALS, and recent objective studies indicate that the sign has a high degree of specificity.

Jiang H.,Chiba University | Sugiyama T.,Chiba University | Hamajima A.,Chiba University | Hamada Y.,Chiba University
Advanced Synthesis and Catalysis | Year: 2011

The Shi-type epoxidation of O-tert-butyldiphenylsilyl (TBDPS) protected o-allylphenols serves as an efficient strategy to construct the dihydrobenzofurans and dihydrobenzopyrans in up to 97% ee. This methodology led to the enantioselective synthesis of (+)-marmesin, (-)-(3′R)-decursinol, and (+)-lomatin. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Shirota H.,Chiba University | Mandai T.,Chiba University | Fukazawa H.,Chiba University | Kato T.,Chiba University
Journal of Chemical and Engineering Data | Year: 2011

We report the data of liquid density, thermal properties including glass transition temperature, melting point, and decomposition temperature, surface tension, and shear viscosity for imidazolium-based dicationic ionic liquids with the anions of bis(trifluoromethylsulfonyl)amide, bis(pentafluoroethylsulfonyl) amide, tetrafluoroborate, and nitrate. To find the unique and general features of the dicationic ionic liquids, data of their corresponding monocationic ionic liquids are also summarized. The results of the dicationic ionic liquids showed that the density was high; the glass transition temperature and melting point were high, and they were thermally stable. Also the surface tension was large, and the shear viscosity was high in comparison with the reference monocationic ionic liquids. The data of the physical properties including liquid density, surface tension, and shear viscosity of the ionic liquids were also compared with that of alkanediols and alkyl alcohols to find the alkyene-linker and alkyl-group dependences in the ionic liquids and alcohols. © 2011 American Chemical Society.

Akutsu Y.,Chiba University | Matsubara H.,Chiba University
Surgery Today | Year: 2011

The revision of the TNM Classification of Malignant Tumors, 7th Edition, suggests the lymph node (LN) status to be the most significant risk factor in esophageal cancer. This article reviews the current status of LNs as indicators of prognosis. The significance of the number of metastatic LNs, the number of resected LNs, and a novel index, the "LN ratio" (metastatic LNs/removed LNs) in patients with esophageal cancer, were reviewed. The number of metastatic LNs independently predicted the prognosis of both overall survival and relapse-free survival. The number of positive LNs was also the best predictive marker of survival. Furthermore, overall survival significantly depended on the number of surgically removed LNs, and the LN ratio closely correlated with survival. The LN status is considered to be the most significant information that can be used to predict the prognosis. However, there are many issues that still need to be resolved. Better knowledge of the N-status is therefore needed to effectively utilize this information. Further research should focus on the N-status of patients with esophageal cancer. © 2011 Springer.

Ahmed N.,Chiba University | Shibata Y.,Chiba University | Taniguchi T.,Chiba University | Izumi Y.,Chiba University
Journal of Catalysis | Year: 2011

Ordered layered double hydroxides (LDHs) consisting of zinc and/or copper hydroxides were synthesized and combined with aluminum or gallium. These LDH compounds were then applied as photocatalysts to convert gaseous CO2 (2.3 kPa) to methanol or CO under UV-visible light using hydrogen. ZnAl LDH was the most active for CO2 photoreduction and the major product was CO formed at a rate of 620nmolh-1gcat-1, whereas methanol was the major product formed by the inclusion of Cu in the LDH photocatalysts, e.g., at a formation rate of 170nmol h-1 gcat -1 using ZnCuGa photocatalyst. The methanol selectivity improved by the inclusion of Cu from 5.9 to 26 mol% and 39 to 68 mol%, respectively, when ZnAl (the conversion 0.16-0.11%) and ZnGa LDH catalysts were used (the conversion 0.02-0.03%). Specific interaction of Cu sites with CO2 was spectroscopically suggested to enable coupling with protons and photogenerated electrons to form methanol. © 2011 Elsevier Inc. All rights reserved.

Kim J.,Chiba University | Yamada Y.,Chiba University | Sato S.,Chiba University
Journal of Physical Chemistry C | Year: 2014

Mechanisms for pyrolysis of epoxidized fullerene involving formation of CO, CO2, and O2 gases were studied using density functional theory calculation. From two oxygen atoms on fullerene, a lactone group is formed through migration of an oxygen atom. The lactone group is transformed into either CO2 gas with a monovacancy defect or a combination of an ether group and a ketone group. The ketone group in the combination of the ether group and the ketone group decomposes into CO gas. All of these mechanisms proceed endothermically, but CO gas tends to form more than CO2 gas because the activation energy required for the formation of CO gas is lower than that of CO2 gas. From three oxygen atoms on fullerene, a combination of a lactone group and a ketone group is generated and decomposes into CO and CO2 gases. CO2 gas tends to form more than CO gas because the activation energy required for the formation of CO2 gas is lower than that of CO gas. O2 gas is difficult to desorb because of the high activation energy. © 2014 American Chemical Society.

Kuwabara S.,Chiba University
Brain and Nerve | Year: 2011

The neuromuscular junction (NMJ) is a specialized synapse with a complex structural organization. Muscle contraction involves several steps: (1) nerve conduction to depolarize the motor nerve terminals, (2) opening of voltage-gated calcium channels (VGCCs) in the presynaptic membrane, (3) generation of endplate potential in the postsynaptic membrane via acetylcholine receptors, (4) depolarization of muscle sodium channels, and (5) excitation-contraction (E-C) coupling. Each step can be affected by various diseases. Guillain-Barre syndrome involves distal axons and possibly the presynaptic NMJ. The abnormalities can be detected by nerve conduction studies and single-fiber electromyography (SFEMG). Myasthenia gravis (MG) with anti-acetylcholine receptor (AChR) antibodies, is the most common NMJ disorder, and ∼5% of myasthenia patients are positive for anti-muscle specific kinase (MuSK) antibodies. Patterns and severity of neuromuscular transmission failure detected by repetitive nerve stimulation test and SFEMG are somewhat different in AChR-MG and MuSK-MG. Excitation-contraction (E-C) coupling can be affected by MG, possibly via antibodies against ryanodine receptors. The E-C coupling time can be assessed with an accelerometer. Lambert-Eaton myasthenic syndrome is caused by antibodies against presynaptic VGCCs. This review will focus on neurophysiological testing, including SFEMG, and measurements of E-C coupling time with an accelerometer. In addition to confirming or excluding the diagnosis, these techniques can provide new insights into the pathophysiology of a variety of neuromuscular disorders.

Yamamura S.,Japan National Institute of Environmental Studies | Amachi S.,Chiba University
Journal of Bioscience and Bioengineering | Year: 2014

Arsenic (As) contamination of drinking water and soils poses a threat to a large number of people worldwide, especially in Southeast Asia. The predominant forms of As in soils and aquifers are inorganic arsenate [As(V)] and arsenite [As(III)], with the latter being more mobile and toxic. Thus, redox transformations of As are of great importance to predict its fate in the environment, as well as to achieve remediation of As-contaminated water and soils. Although As has been recognized as a toxic element, a wide variety of microorganisms, mainly bacteria, can use it as an electron donor for autotrophic growth or as an electron acceptor for anaerobic respiration. In addition, As detoxification systems in which As is oxidized to the less toxic form or reduced for subsequent excretion are distributed widely in microorganisms. This review describes current development of physiology, biochemistry, and genomics of arsenic-transforming bacteria. Potential application of such bacteria to removal of As from soils and water is also highlighted. © 2013 The Society for Biotechnology, Japan.

Stoeber J.,University of Kent | Kobori O.,Chiba University | Brown A.,University of Kent
Assessment | Year: 2014

Perfectionism cognitions capture automatic perfectionistic thoughts and have explained variance in psychological adjustment and maladjustment beyond trait perfectionism. The aim of the present research was to investigate whether a multidimensional assessment of perfectionism cognitions has advantages over a unidimensional assessment. To this aim, we examined in a sample of 324 university students how the Perfectionism Cognitions Inventory (PCI) and the Multidimensional Perfectionism Cognitions Inventory (MPCI) explained variance in positive affect, negative affect, and depressive symptoms when factor or subscale scores were used as predictors compared to total scores. Results showed that a multidimensional assessment (PCI factor scores, MPCI subscale scores) explained more variance than a unidimensional assessment (PCI and MPCI total scores) because, when the different dimensions were entered simultaneously as predictors, perfectionistic strivings cognitions and perfectionistic concerns cognitions acted as mutual suppressors thereby increasing each others’ predictive validity. With this, the present findings provide evidence that—regardless of whether the PCI or the MPCI is used—a multidimensional assessment of perfectionism cognitions has advantages over a unidimensional assessment in explaining variance in psychological adjustment and maladjustment. © The Author(s) 2014.

Ishikawa M.,Chiba University | Hashimoto K.,Chiba University
Journal of Receptor, Ligand and Channel Research | Year: 2010

The endoplasmic reticulum protein sigma-1 receptors, first regarded as opioid receptors and later confused as the phencyclidine (PCP) binding sites of the N-methyl-D-aspartate (NMDA) receptor, are now confirmed to be independent receptors. They are involved in the modulation of various neurotransmitter systems and have a high affinity for diverse classes of psychotropic drugs. Accumulating evidence suggests that the sigma-1 receptors are implicated in higher-ordered brain functions and play important roles in the pathophysiology of neuropsychiatric diseases such as schizophrenia, depression, anxiety disorders, and dementia. Recently, sigma-1 receptors have been shown to function at the molecular level as "receptor chaperones." This mechanism may unify the explanation of the role of sigma-1 receptors in the pathophysiology of neuropsychiatric diseases. With the development of the positron emission tomography (PET) ligand [11C]SA4503, it has become possible to visualize sigma-1 receptors and estimate the sigma-1 receptor occupancy of drugs in the human brain. This approach may provide additional information on the function of sigma-1 receptors. This article reviews the function of sigma-1 receptors and attempts to reinterpret their role in the pathophysiology of neuropsychiatric diseases based on their new description as "receptor chaperones." © 2010 Ishikawa and Hashimoto, publisher and licensee Dove Medical Press Ltd.

Katsuura T.,Chiba University
Journal of physiological anthropology | Year: 2012

It has been assumed that light with a higher irradiance of pulsed blue light has a much greater influence than that of light with a lower irradiance of steady blue light, although they have the same multiplication value of irradiance and duration. We examined the non-visual physiological effects of blue pulsed light, and determined whether it is sensed visually as being blue. Seven young male volunteers participated in the study. We placed a circular screen (diameter 500 mm) in front of the participants and irradiated it using blue and/or white light-emitting diodes (LEDs), and we used halogen lamps as a standard illuminant. We applied three steady light conditions of white LED (F0), blue LED + white LED (F10), and blue LED (F100), and a blue pulsed light condition of a 100-μs pulse width with a 10% duty ratio (P10). The irradiance of all four conditions at the participant's eye level was almost the same, at around 12 μW/cm2. We measured their pupil diameter, recorded electroencephalogram readings and Kwansei Gakuin Sleepiness Scale score, and collected subjective evaluations. The subjective bluish score under the F100 condition was significantly higher than those under other conditions. Even under the P10 condition with a 10% duty ratio of blue pulsed light and the F10 condition, the participant did not perceive the light as bluish. Pupillary light response under the P10 pulsed light condition was significantly greater than under the F10 condition, even though the two conditions had equal blue light components. The pupil constricted under the blue pulsed light condition, indicating a non-visual effect of the lighting, even though the participants did not perceive the light as bluish.

Lee S.,Chiba University
Journal of physiological anthropology | Year: 2012

Recently, mist saunas have been used in the home as a new bathing style in Japan. However, there are still few reports on the effects of bathing methods on recovery from muscle fatigue. Furthermore, the effect of mist sauna bathing on human physiological function has not yet been revealed. Therefore, we measured the physiological effects of bathing methods including the mist sauna on recovery from muscle fatigue. The bathing methods studied included four conditions: full immersion bath, shower, mist sauna, and no bathing as a control. Ten men participated in this study. The participants completed four consecutive sessions: a 30-min rest period, a 10-min all out elbow flexion task period, a 10-min bathing period, and a 10-min recovery period. We evaluated the mean power frequency (MNF) of the electromyogram (EMG), rectal temperature (Tre), skin temperature (Tsk), skin blood flow (SBF), concentration of oxygenated hemoglobin (O2Hb), and subjective evaluation. We found that the MNF under the full immersion bath condition was significantly higher than those under the other conditions. Furthermore, Tre, SBF, and O2Hb under the full immersion bath condition were significantly higher than under the other conditions. Following the results for the full immersion bath condition, the SBF and O2Hb of the mist sauna condition were significantly higher than those for the shower and no bathing conditions. These results suggest that full immersion bath and mist sauna are effective in facilitating recovery from muscle fatigue.

Igarashi K.,Chiba University | Igarashi K.,Amine Pharma Research Institute | Kashiwagi K.,Chiba Institute of Science
International Journal of Biochemistry and Cell Biology | Year: 2010

Polyamines (putrescine, spermidine and spermine) are essential for normal cell growth. The polyamine levels in cells are regulated by biosynthesis, degradation, and transport. Polyamines can modulate the functions of DNA, nucleotide triphosphates, proteins, and especially RNA because most polyamines exist in a polyamine-RNA complex in cells. Thus, the major focus on this review is on the role of polyamines in protein synthesis. In addition, effects of polyamines on B to Z conversion of DNA, transcription, phosphorylation of proteins, cell cycle progression, apoptosis and ion channels, especially NMDA receptors, are outlined. The function of eIF5A is also briefly discussed. Finally, a correlation between acrolein, produced from polyamines by polyamine oxidases, and chronic renal failure or brain stroke is summarized. Increased levels of polyamine oxidases and acrolein are good markers of chronic renal failure and brain stroke. © 2009 Elsevier Ltd. All rights reserved.

Ohya H.,Chiba University | Shiokawa K.,Nagoya University | Miyoshi Y.,Nagoya University
Journal of Geophysical Research: Space Physics | Year: 2011

We investigated, for the first time, long-term (1976-2010) variations in reflection heights of tweek atmospherics based on very low frequency (VLF) observations at Kagoshima, Japan. The results revealed the effects of the solar cycle on the nighttime lower ionosphere at low to middle latitudes. The tweek reflection heights on geomagnetically quiet days were analyzed every month over three solar cycles by using an automated spectral fitting procedure to estimate the cutoff frequency. The average and standard deviation of the reflection height were 95.9 km and ±3.1 km, respectively. Typical periods of time variation for the reflection height were 13.3, 3.2, 1.3, 1.0, 0.6, and 0.5 years. The variations in tweek reflection heights did not show simple anticorrelation with solar activity. The correlation coefficient between tweek reflection height and sunspot number was 0.03 throughout the three solar cycles. Hilbert-Huang transform analysis successfully indicated the presence of 0.5-1.5 year and ∼10 year variations as intrinsic mode functions (IMF). The decomposed IMF with the ∼10 year variation had a positive correlation with sunspot numbers and a negative correlation with galactic cosmic rays (GCRs). We hypothesize that these variations in tweek reflection heights could be caused by coupling of several ionization effects at the D and lower E regions, effects such as geocorona, GCRs, particle precipitation, and variations in neutral density in the lower thermosphere. Among these processes, the geocorona and particle precipitation could show negative correlation, while the GCRs and neutral density could show positive correlation with solar activities. Copyright 2011 by the American Geophysical Union.

Yamada T.,Chiba University
Advances in Intelligent Systems and Computing | Year: 2016

Information and Communication Technologies (ICTs) have triggered the innovations of pedagogies and learning methods in all levels of education. In addition to distance education, e-Learning is expected to improve classroom teaching through educational tools and digital content in various blended approaches; Mobile devices and SNS showed the new content distribution and knowledge sharing in learner communities; MOOCs (Massive Open Online Courses) expanded the opportunities of quality education on a global level. This paper discusses the Japanese practices in which MOOCs acted as catalysts implementing component technologies and development strategies for e-Learning. © Springer International Publishing Switzerland 2016.

Nakanishi M.,Chiba University | Hashimoto J.,Nagasaki University
Marine Geophysical Research | Year: 2011

Data from three bathymetric surveys by R/V Kairei using a 12-kHz multibeam echosounder and differential GPS were used to create an improved topographic model of the Challenger Deep in the southwestern part of the Mariana Trench, which is known as the deepest seafloor in the world. The strike of most of the elongated structures related to plate bending accompanied by subduction of the Pacific plate is N70°E and is not parallel to the trench axis. The bending-related structures were formed by reactivation of seafloor spreading fabric. Challenger Deep consists of three en echelon depressions along the trench axis, each of which is 6-10 km long, about 2 km wide, and deeper than 10,850 m. The eastern depression is the deepest, with a depth of 10,920 ± 5 m. © 2011 Springer Science+Business Media B.V.

Matsuda S.,Chiba University
Progress in neuro-psychopharmacology & biological psychiatry | Year: 2010

Several lines of evidence suggest that the N-methyl-D-aspartate (NMDA) receptor plays a significant role in fear conditioning and extinction. However, our knowledge of the role of D-serine, an endogenous ligand for the glycine site of the NMDA receptor, in fear extinction is quite limited compared to that of D-cycloserine, an exogenous partial agonist for the same site. In the current study, we examined the effects of D-serine on fear extinction and phosphorylation of extracellular signal-regulated kinase (ERK) in the hippocampus, basolateral amygdala (BLA), and medial prefrontal cortex (mPFC) during the process of fear extinction. Systemic administrations of D-serine (2.7 g/kg, i.p.) with or without the ERK inhibitor SL327 (30 mg/kg, i.p.) to C57BL/6J mice were performed before fear extinction in a cued fear conditioning and extinction paradigm. Cytosolic and nuclear ERK 1/2 phosphorylation in the hippocampus, BLA, and mPFC were measured 1h after extinction (E1h), 24h after extinction (E24h), and 1h after recall (R1h) by Western blotting. We found that D-serine enhanced the extinction of fear memory, and the effects of D-serine were reduced by the ERK phosphorylation inhibitor SL327. The Western blot analyses showed that D-serine significantly increased cytosolic ERK 2 phosphorylation at E1h in the hippocampus and cytosolic ERK 1/2 phosphorylation at R1h in the BLA. The present study suggested that D-serine might enhance fear extinction through NMDA receptor-induced ERK signaling in mice, and that D-serine has potential clinical importance for the treatment of anxiety disorders. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Jiao Y.,Tokyo Institute of Technology | Yamada S.,Tokyo Institute of Technology | Kishiki S.,Tokyo Institute of Technology | Shimada Y.,Chiba University
Earthquake Engineering and Structural Dynamics | Year: 2011

The energy dissipation capacity of a structure is a very important index that indicates the structural performance in energy-based seismic design. This index depends greatly on the structural components that form the whole system. Owing to the wide use of the strong-column weak-beam strength hierarchy where steel beams dissipate the majority of earthquake input energy to the structures, it is necessary to evaluate the energy dissipation capacity of the beams. Under cyclic loadings such as seismic effects, the damage of the beams accumulates. Therefore, loading history is known to be the most pivotal factor influencing the deformation capacity and energy dissipation capacity of the beams. Seismic loadings with significantly different characteristics are applied to structural beams during different types of earthquakes and there is no unique appropriate loading protocol that can represent all types of seismic loadings. This paper focuses on the effects of various loading histories on the deformation capacity and energy dissipation capacity of the beams. Cyclic loading tests of steel beams were performed. In addition, some experimental results from published tests were also collected to form a database. This database was used to evaluate the energy dissipation capacity of steel beams suffering from ductile fracture under various loading histories. © 2011 John Wiley & Sons, Ltd.

Satish-Kumar M.,University of Shizuoka | So H.,University of Shizuoka | Yoshino T.,Okayama University | Kato M.,Chiba University | Hiroi Y.,Chiba University
Earth and Planetary Science Letters | Year: 2011

We report here new experimental data on equilibrium carbon isotope fractionation between graphite/diamond and iron carbide melt at 5 and 10GPa and in the temperature range between 1200 and 2000°C. Carbon isotope equilibrium was tested using morphological features of graphite and also by performing a longer duration experiment, both of which suggested that equilibrium carbon isotope fractionation is present. The results suggest that iron carbide melt will preferentially accumulate 12C rather than 13C. An equilibrium temperature dependent fractionation between iron carbide melt and graphite/diamond is proposed based on the relationδ13C(gr/dia - iron carbide melt)=8.85106/T2K+0.99.Our results are consistent with the carbon isotope distribution between graphite and cohenite (Fe3C) observed in iron meteorites. We propose that temperature-dependent fractionation of carbon isotopes between iron carbide melt and graphite/diamond might have created a "12C-enriched core" with a significant difference in the distribution of carbon isotopes between the carbon in the metallic core and bulk silicate Earth during the accretion and differentiation of early Earth. Recent findings of low δ13C carbonados and diamonds of deep mantle origin supports the presence of a 12C enriched source. The possible presence of a reservoir of12C-enriched carbon in the Earth's core implies that it can generate large perturbations in the surface and shallow carbon-isotope system by the flux of lighter carbon from the core-mantle boundary. © 2011 Elsevier B.V..

Ashida H.,Tokyo Medical University | Nakano H.,Juntendo University | Sasakawa C.,Tokyo Medical University | Sasakawa C.,Nippon Institute for Biological Science | Sasakawa C.,Chiba University
PLoS Pathogens | Year: 2013

NF-κB plays a central role in modulating innate immune responses to bacterial infections. Therefore, many bacterial pathogens deploy multiple mechanisms to counteract NF-κB activation. The invasion of and subsequent replication of Shigella within epithelial cells is recognized by various pathogen recognition receptors as pathogen-associated molecular patterns. These receptors trigger innate defense mechanisms via the activation of the NF-κB signaling pathway. Here, we show the inhibition of the NF-κB activation by the delivery of the IpaH E3 ubiquitin ligase family member IpaH0722 using Shigella's type III secretion system. IpaH0722 dampens the acute inflammatory response by preferentially inhibiting the PKC-mediated activation of NF-κB by ubiquitinating TRAF2, a molecule downstream of PKC, and by promoting its proteasome-dependent degradation. © 2013 Ashida et al.

Hashimoto K.,Chiba University
Expert Opinion on Therapeutic Targets | Year: 2016

The N-methyl-D-aspartate (NMDA) receptor antagonist ketamine is one of the most attractive antidepressants since this drug causes rapid-onset and sustained antidepressant effects in treatment resistant patients with depression. There are unanswered questions about how ketamine induces its rapid and sustained antidepressant actions. This key article suggests that (2R,6R)-HNK (hydroxynorketamine), a major metabolite of (R)-ketamine, shows antidepressant effects in rodent models of depression, indicating that the metabolism of (R)-ketamine to (2R,6R)-HNK is pivotal in its antidepressant action. Here these findings are put into context and their significance is discussed. © 2016 Informa UK Limited, trading as Taylor & Francis Group

Sakao S.,Chiba University | Tatsumi K.,Chiba University | Voelkel N.F.,Virginia Commonwealth University
American Journal of Respiratory Cell and Molecular Biology | Year: 2010

Vascular remodeling is an important pathological feature of pulmonary arterial hypertension (PAH), which leads to increased pulmonary vascular resistance, with marked proliferation of pulmonary artery smooth muscle cells (SMC) and/or endothelial cells (EC). Successful treatment of experimental PAH with a platelet-derived growth factor (PDGF) receptor tyrosine kinase inhibitor offers the perspective of "reverse remodeling" (i.e., the regression of established pulmonary vascular lesions). Here we ask the question: which forms of pulmonary vascular remodeling are reversible and can such remodeling caused by angiogenic proliferation of EC be reversed? It is important to emphasize that the report showing reduction of vascular remodeling by PDGF receptor tyrosine kinase inhibitor showed only a reduction of the pulmonary artery muscularization in chronic hypoxia and monocrotaline models, which lack the feature of clustered proliferated EC in the lumen of pulmonary arteries. The regression of vascular muscularization is an important manifestation, whereby proliferative adult SMC convert back to a nonproliferative state. In contrast, in vitro experiments assessing the contribution of EC to the development of PAH demonstrated that phenotypically altered EC generated as a consequence of a vascular endothelial growth factor receptor blockade did not reverse to normal EC. Whereas it is suggested that the proliferative state of SMC may be reversible, it remains unknown whether phenotypically altered EC can switch back to a normal monolayer-forming EC. This article reviews the pathogenetic concepts of severe PAH and explains the many forms in PAH with reversible or irreversible remodeling.

Fujii K.,Chiba University | Miyashita T.,Kitasato University
Pediatrics International | Year: 2014

Gorlin syndrome, also called nevoid basal cell carcinoma syndrome, is an autosomal dominant neurocutaneous disease characterized by developmental anomalies such as palmar pits and rib anomaly, and tumorigenesis such as medulloblastoma and basal cell carcinoma. This syndrome is mainly caused by a mutation of PTCH1, a human homologue of Drosophila patched, including frameshift, missense, or nonsense mutations. Genotype-phenotype correlation has not been established. PTCH1 is a member of hedgehog signaling, which is a highly conserved pathway in vertebrates, composed of hedgehog, SMO, and GLI proteins as well as PTCH1. Given that hedgehog signaling regulates cell growth and development, disorder of this pathway gives rise to not only developmental anomalies but also diverse tumors such as those seen in Gorlin syndrome. We recently reported, for the first time, a nationwide survey of Gorlin syndrome in Japan, noting that the frequency was 1/235 800 in the Japanese population, and that the frequency of basal cell carcinomas was significantly lower in Japan than in the USA and Europe, suggesting that ethnicity and genetic background contribute to these differences. Given that many clinical trials using newly discovered molecular inhibitors are still ongoing, these agents should become the new therapeutic options for hedgehog pathway-dependent tumors in patients with or without Gorlin syndrome. © 2014 Japan Pediatric Society.

Hayati M.,Razi University | Lotfi A.,Razi University | Kazimierczuk M.K.,Wright State University | Sekiya H.,Chiba University
IEEE Transactions on Power Electronics | Year: 2013

This paper presents analytical expressions for the class-E power amplifier with MOSFET linear gate-to-drain and nonlinear drain-to-source parasitic capacitances at any duty ratio. The maximum operating frequency, output power capability, and element values as functions of the duty ratio are obtained. The element values are directly dependent upon the selection of duty ratio and require a careful duty ratio selection to minimize component power losses and to maximize the total efficiency. Two design examples at 25 and 9 W output power at 4-MHz operating frequency along with the PSpice-simulation and experimental waveforms are presented. It is shown from the derived expressions that the slope of the voltage across the MOSFET gate-to-drain parasitic capacitance during the switch-off state as a function of the duty ratio affects the switch-voltage waveform. Therefore, it is possible to achieve the required peak switch voltage and the class-E ZVS/ZVDS conditions simultaneously by adjusting the duty ratio. The theoretical results and PSpice simulations agreed with experimental results quantitatively, which shows the validity of the presented analysis. © 1986-2012 IEEE.

Furusawa Y.,Keio University | Furusawa Y.,Tokyo Medical University | Obata Y.,Tokyo Medical University | Obata Y.,Chiba University | And 2 more authors.
Seminars in Immunopathology | Year: 2015

Commensal microbiota shapes the intestinal immune system by regulating T helper(TH)cell lineage differentiation. For example, Bacteroides fragilis colonization not only optimizes the systemic TH1/TH2 balance, but also can induce regulatory T (Treg) cell differentiation in the gut. In addition, segmented filamentous bacteria (SFB) facilitate the development of TH17 cells in the small intestine. The 17 strains within clusters IV, XIVa, and XVIII of Clostridiales found in human feces can also induce the differentiation and expansion of Treg cells in the colon. Thus, the regulation of THcell differentiation by commensal bacteria is evident; however, the molecular mechanisms underlying these processes remain uncertain. Recent studies have demonstrated that bacterial components, as well as their metabolites, play a central role in regulating THcell development. Furthermore, these metabolites can elicit changes in histone posttranslational modification to modify the expression of critical regulators of T cell fate. In this review, we discuss the mechanisms and biological significance of microbiota-dependent THdifferentiation. © 2014, Springer-Verlag Berlin Heidelberg.

Gonzalez J.,Chiba University | Soma H.,Chiba University | Sekine M.,Chiba University | Yu W.,Chiba University
Journal of NeuroEngineering and Rehabilitation | Year: 2012

Background: Prosthetic hand users have to rely extensively on visual feedback, which seems to lead to a high conscious burden for the users, in order to manipulate their prosthetic devices. Indirect methods (electro-cutaneous, vibrotactile, auditory cues) have been used to convey information from the artificial limb to the amputee, but the usability and advantages of these feedback methods were explored mainly by looking at the performance results, not taking into account measurements of the users mental effort, attention, and emotions. The main objective of this study was to explore the feasibility of using psycho-physiological measurements to assess cognitive effort when manipulating a robot hand with and without the usage of a sensory substitution system based on auditory feedback, and how these psycho-physiological recordings relate to temporal and grasping performance in a static setting. Methods: 10 male subjects (26+/-years old), participated in this study and were asked to come for 2 consecutive days. On the first day the experiment objective, tasks, and experiment setting was explained. Then, they completed a 30 minutes guided training. On the second day each subject was tested in 3 different modalities: Auditory Feedback only control (AF), Visual Feedback only control (VF), and Audiovisual Feedback control (AVF). For each modality they were asked to perform 10 trials. At the end of each test, the subject had to answer the NASA TLX questionnaire. Also, during the test the subjects EEG, ECG, electro-dermal activity (EDA), and respiration rate were measured. Results: The results show that a higher mental effort is needed when the subjects rely only on their vision, and that this effort seems to be reduced when auditory feedback is added to the human-machine interaction (multimodal feedback). Furthermore, better temporal performance and better grasping performance was obtained in the audiovisual modality. Conclusions: The performance improvements when using auditory cues, along with vision (multimodal feedback), can be attributed to a reduced attentional demand during the task, which can be attributed to a visual pop-out or enhance effect. Also, the NASA TLX, the EEGs Alpha and Beta band, and the Heart Rate could be used to further evaluate sensory feedback systems in prosthetic applications. © 2012 Gonzalez et al.; licensee BioMed Central Ltd.

Hayati M.,Razi University | Lotfi A.,Razi University | Kazimierczuk M.K.,Wright State University | Sekiya H.,Chiba University
IEEE Transactions on Power Electronics | Year: 2013

This paper presents analytical expressions for the class-E power amplifier with a shunt inductor for satisfying the subnominal condition and 50% duty ratio. The subnominal condition means that only the zero-current switching condition (ZCS) is achieved, though the nominal conditions mean that both the ZCS and zero-current derivative switching (ZCDS) are satisfied. The design values for achieving the subnominal condition are expressed as a function of the phase shift between the input and output voltages. The class-E amplifier with subnominal condition increases one design degree of freedom compared with that with the nominal conditions. Because of the increase in the design degree of freedom, one more relationship can be specified as a design specification. It is shown analytically that the dc-supply voltage and the current are always proportional to the amplitude of the output voltage and the current as a function of the phase shift. Additionally, the output power capability is affected by the phase shift, and the peak switch voltage has influence on the phase shift as well. This paper gives a circuit design example based on our proposed design expression by specifying the peak switch voltage instead of the ZCDS condition. The measurement and PSpice simulation results agree with the analytical expressions quantitatively, which show the validity of our analytical expressions. © 1986-2012 IEEE.

Sebe F.,Chiba University | Nishikawa K.,Chiba University | Koga Y.,University of British Columbia
Physical Chemistry Chemical Physics | Year: 2012

Our earlier thermodynamic studies suggested that F - and Cl - form hydration shells with the hydration number 14 ± 2 and 2.3 ± 0.6, respectively, and leave the bulk H 2O away from hydration shells unperturbed. Br - and I -, on the other hand, form hydrogen bonds directly with the momentarily existing hydrogen bond network of H 2O, and retard the degree of entropy-volume cross fluctuation inherent in liquid H 2O. The effect of the latter is stronger for I - than Br -. Here we seek additional information about this qualitative difference between Cl - and (Br - and I -) pair by near infrared (NIR) spectroscopy. We analyze the ν 2 + ν 3 band of H 2O in the range 4600-5500 cm -1 of aqueous solutions of NaCl, NaBr and NaI, by a new approach. From observed absorbance, we calculate excess molar absorptivity, ε E, excess over the additive contributions of solute and solvent. ε E thus contains information about the effect of inter-molecular interactions in the ν 2 + ν 3 spectrum. The spectrum of ε E shows three bands; two negative ones at 5263 and 4873 cm -1, and the positive band at 5123 cm -1. We then define and calculate the excess partial molar absorptivity of each salt, εEsalt. From the behaviour of εEsalt we suggest that the negative band at 5263 cm -1 represents free H 2O without much hydrogen bonding under the influence of local electric field of ions. Furthermore, from a sudden change in the x salt (mole fraction of salt) dependence of εEsalt, we suggest that there is an ion-pairing in x salt > 0.032, 0.036, and 0.04 for NaCl, NaBr and NaI respectively. The positive band of ε E at 5123 cm -1 is attributed to a modestly organized hydrogen bond network of H 2O (or liquid-likeness), and the x salt dependence of εEsalt indicated a qualitative difference in the effect of Cl - from those of Br - and I -. Namely, the values of εEsalt stay constant for Cl - but those for Br - and I - decrease smoothly on increasing the salt mole fraction. The mole fraction dependence of εEsalt at the 4873 cm -1 band, due to ice-likeness in H 2O, shows a subtle difference between Cl - and (Br -, I -) pair. © 2012 the Owner Societies.

Ito K.,Chiba University | Haga N.,Chiba University
International Conference on Applications of Electromagnetism and Student Innovation Competition Awards, AEM2C 2010 | Year: 2010

In recent years, a study on body-centric wireless communications has become an active and attractive area of research because of their various applications such as e-healthcare, support systems for specialized occupations, personal communications, and so on. Whereas UHF bands are subjects of interest especially in Europe and USA, relatively low frequency bands below several megahertz are of great interest especially in Japan. Hence, all of the prospective frequencies are in an extremely wide range, and an objective idea on how to select a right frequency band for individual applications is required. Currently in our laboratory, we have been studying on frequency dependence of basic characteristics of wearable antennas as well as body-centric wireless communication channels in the range of HF to UHF (3 MHz-3 GHz). There are experimental, analytical, and numerical ways to clarify the basic characteristics of the antennas and communication channels. In experiments, we have to ensure impedance matching at certain frequency points because of sensitivity limitations; therefore, it is hard to obtain such broadband characteristics. Theoretical analysis is useful to understand physical mechanism; however, complex geometry and motion of the human body cannot be modeled. By contrast to them, numerical simulation can solve complex problems with relative ease. For example, Hall et al. have shown that the dynamics of the human body can be modeled by dividing the motion into several frames, and the simulated results agree with the measured results. Also in our study, observations of channel characteristics are conducted by employing numerical simulations. In this paper, firstly, electric field distributions around the human body wearing a small top-loaded monopole antenna are numerically calculated and compared in a wide range of HF to UHF bands. Then, received open voltages at receiving antennas which are equipped at several different points on the human body are numerically investigated. The received open voltages are also numerically calculated and compared with several different postures of the human body. Statistic characterization and experimental validation will be necessary in further studies. ©2010 IEEE.

Sun D.,Chiba University | Yamada Y.,Chiba University | Sato S.,Chiba University
Applied Catalysis A: General | Year: 2014

The vapor-phase hydrogenolysis of glycerol was performed at a gradient temperature and ambient hydrogen pressure over a commercial Cu/Al 2O3 catalyst modified with silver. Addition of Ag into Cu/Al2O3 catalysts was found to be efficient in inhibiting the decomposition of glycerol to produce ethylene glycol and gave a yield of 1,2-propanediol higher than that of the original Cu/Al2O3 without Ag. To minimize the ethylene glycol formation, the suitable loading of Ag was 1 wt.%. Since the Ag loading decreases the hydrogenation ability of the Cu/Al2O3 catalyst, 1 wt.% Ag-loaded Cu/Al 2O3 catalyst was placed on the upper layer of the fixed catalyst bed and the Cu/Al2O3 catalyst was placed on the bottom layer for achieving much higher 1,2-propanediol yield. The effect of temperatures of the top, the interlayer, and the bottom of the catalyst bed on the yield was also examined: a high 1,2-propanediol yield of 98.3%, which is the highest value under ambient H2 pressure conditions, was achieved at a gradient temperature from 170 to 105 C and a glycerol concentration of 15 wt.%. © 2014 Elsevier B.V.

Abe E.,University of Tokyo | Ono A.,University of Tokyo | Itoi T.,Chiba University | Yamasaki M.,Kumamoto University | Kawamura Y.,Kumamoto University
Philosophical Magazine Letters | Year: 2011

A series of structural polytypes formed in an Mg-1 at.%Zn-2 at.%Y alloy has been identified, which are reasonably viewed as long-period stacking derivatives of the hexagonal-close-packed Mg structure with alternate AB stacking of the close-packed atomic layers. Atomic-resolution Z-contrast imaging clearly revealed that the structures are long-period chemical-ordered as well as stacking-ordered; unique chemical order along the stacking direction occurs as being synchronized with a local faulted stacking of AB'C'A, where B' and C' layers are commonly enriched by Zn/Y atoms. © 2011 Taylor & Francis.

Ito K.,Chiba University | Haga N.,Gunma University | Takahashi M.,Chiba University | Saito K.,Chiba University
Proceedings of the IEEE | Year: 2012

In recent years, body-centric wireless communications have been studied because they have potential to improve the qualities of various kinds of applications. Since the prospective frequencies for the body-centric wireless communications are in an extremely wide range from megahertz to gigahertz, an objective idea on how to select a right frequency band for individual applications is required. However, few publications have tackled this need. In this paper, the frequency dependence of the communication channels in the range of 3 MHz to 3 GHz is assessed based on numerical analyses. © 2012 IEEE.

Misawa S.,Chiba University
Brain and Nerve | Year: 2014

The diagnosis of amyotrophic lateral sclerosis (ALS) is frequently challenging, because motor neuron involvement is usually focal at disease onset and many syndromes mimic ALS. Neurological examination and needle EMG are important in the diagnosis of ALS, and patients with early-stage ALS usually undergo several EMG examinations before the diagnosis is confirmed. Ultrasonography has recently been used for the non-invasive assessment of neuromuscular disorders. This review discusses the recent advances in ultrasonography for ALS diagnosis. Ultrasonography could help detect lower motor neuron involvement by evaluating muscle volume, echo intensity, and fasciculations. Previous reports have documented the diagnostic values of all these parameters. In particular, fasciculations are characteristic features of ALS that can be easily and reliably visualized using ultrasonography. Moreover, the combined use of ultrasonography and EMG to detect fasciculations could substantially increase the diagnostic sensitivity of Awaji criteria for ALS. Attempts to utilize ultrasonography for ALS diagnosis have started only recently, and the technique used is yet to be standardized. However, ultrasonography has a major advantage over EMG in that it is non-invasive. Further studies are needed to understand the use of ultrasound as a novel non-invasive tool for ALS diagnosis.

Tanaka G.,Gunma Museum of Natural History | Naruse H.,Kyoto University | Yamashita S.,Chiba University | Arai K.,Chiba University
Geophysical Research Letters | Year: 2012

In Rikuzentakata City, Ostracode assemblages in sediment deposited by the Tohoku-Oki earthquake and tsunami of 11 March 2011 revealed that the sediment was derived from the seafloor from at least 9 m water depth, and was transported inland more than 1 km. The tsunami wave height at this location was higher than 10 m. Four hundred fifty seven modern ostracode assemblages were used in the modern analogue technique to estimate the depth source of the tsunami deposited assemblages. The application of this method to paleo-tsunami deposits may provide insight into past tsunami wave height and potentially earthquake slip and magnitude. Copyright 2012 by the American Geophysical Union.

Aripiprazole is an atypical antipsychotic drug approved for the treatment of psychiatric disorders such as schizophrenia, bipolar disorder, major depressive disorder and autism. The drug shows partial agonistic activity at dopamine D(2) receptors and 5-hydroxytryptamine (5-HT) 5-HT(1A) receptors, and antagonistic activity at 5-HT(2A) receptors. However, the precise mechanistic pathways remain unclear. In this study, we examined the effects of aripiprazole on neurite outgrowth. Aripiprazole significantly potentiated nerve growth factor (NGF)-induced neurite outgrowth in PC12 cells, in a concentration-dependent manner. The 5-HT(1A) receptor antagonist WAY-100635, but not the dopamine D(2) receptor antagonist sulpiride, blocked the effects of aripiprazole, although, only partially. Specific inhibitors of inositol 1,4,5-triphosphate (IP(3)) receptors and BAPTA-AM, a chelator of intracellular Ca(2+), blocked the effects of aripiprazole. Moreover, specific inhibitors of several common signaling pathways phospholipase C-γ (PLC-γ), phosphatidylinositol-3 kinase (PI3K), mammalian target of rapamycin, p38 MAPK, c-Jun N-terminal kinase, Akt, Ras, Raf, ERK, MAPK) also blocked the effects of aripiprazole. Using proteomic analysis, we found that aripiprazole significantly increased levels of the heat shock protein Hsp90α in cultured cells. The effects of aripiprazole on NGF-induced neurite outgrowth were significantly attenuated by treatment with Hsp90α RNA interference, but not by the negative control of Hsp90α. These findings suggest that both 5-HT(1A) receptor activation and Ca(2+) signaling via IP(3) receptors, as well as their downstream cellular signaling pathways play a role in the promotion of aripiprazole-induced neurite outgrowth. Furthermore, aripiprazole-induced increases in Hsp90α protein expression may form part of the therapeutic mechanism for this drug.

Horie K.,Japan National Institute of Polar Research | Hokada T.,Japan National Institute of Polar Research | Hiroi Y.,Chiba University | Motoyoshi Y.,Japan National Institute of Polar Research | Shiraishi K.,Japan National Institute of Polar Research
Gondwana Research | Year: 2012

U-Pb zircon geochronology of 6 samples collected from Fyfe Hills (2 felsic orthogneisses and 1 quartzo-feldspathic gneiss) and Mt. Cronus (1 quartzo-feldspathic gneiss and 2 quartzites) in the western part of the Napier Complex, East Antarctica, revealed an Archaean-Proterozoic history ranging from 3128 to 1824. Ma. The absence of ancient evidence >. 3800-3600. Ma indicates that these ages were not always dominant in these two areas. The 3128-2580. Ma protolith ages are similar to those of other areas (e.g., Mt. Riiser-Larsen, Tonagh Island), while the magmatic protolith age of 2741. Ma obtained for the Fyfe Hills orthogneiss is a new component of the Archaean magmatic protolith in the Napier Complex. Metamorphic overgrowth or recrystallized zircons yielded systematic disconformable ages for both Fyfe Hills (>. 2518. Ma) and Mt. Cronus (~. 2490. Ma). The presence of 2580. Ma inherited zircons provides important constraints that place the ultrahigh temperature metamorphic peak later than 2580. Ma. The post metamorphic ages suggest local fluid infiltration or local deformation event(s). © 2011 International Association for Gondwana Research.

Nakada T.-A.,University of British Columbia | Nakada T.-A.,Chiba University | Russell J.A.,University of British Columbia | Boyd J.H.,University of British Columbia | And 2 more authors.
Critical Care Medicine | Year: 2015

Objectives: Mortality from septic shock is highly heritable. The identification of causal genetic factors is insufficient. To discover key contributors, we first identified nonsynonymous single-nucleotide polymorphisms in conserved genomic regions that are predicted to have significant effects on protein function. We then test the hypothesis that these nonsynonymous single-nucleotide polymorphisms across the genome alter clinical outcome of septic shock. Design: Genetic-association study plus in vitro experiment using primary cells plus in silico analysis using genomic DNA and protein database. Setting: Twenty-seven ICUs at academic teaching centers in Canada, Australia, and the United States. Patients: Patients with septic shock of European ancestry (n = 520). Interventions: Patients with septic shock were genotyped for 843 nonsynonymous single-nucleotide polymorphisms in conserved regions of the genome and are predicted to have damaging effects from the protein sequence. Measurements and Main Results: The primary outcome variable was 28-day mortality. Secondary outcome variables were organ dysfunction. Productions of adhesion molecules including interleukin- 8, growth-regulated oncogene-α, monocyte chemoattractant protein-1, and monocyte chemoattractant protein-3 were measured in human umbilical vein endothelial cells after SVEP1 gene silencing by RNA interference. Patients with septic shock having the SVEP1 C allele of nonsynonymous single-nucleotide polymorphism, SVEP1 c.2080A>C (p. Gln581His, rs10817033), had a significant increase in the hazard of death over the 28 days (hazard ratio, 1.72; 95% CI, 1.31-2.26; p = 9.7 × 10-5) and increased organ dysfunction and needed more organ support (p < 0.05). Silencing SVEP1 significantly increased interleukin-8, growth-regulated oncogene-α, monocyte chemoattractant protein-1, monocyte chemoattractant protein-3 production in human umbilical vein endothelial cells under lipopolysaccharide stimulation (p < 0.01). Conclusions: C allele of SVEP1 c.2080A>C (p. Gln581His) single-nucleotide polymorphism, a non-synonymous singlenucleotide polymorphism in conserved regions and predicted to have damaging effects on protein structure, was associated with increased 28-day mortality and organ dysfunction of septic shock. SVEP1 appears to regulate molecules of the leukocyte adhesion pathway.

Ito K.,Chiba University
IEEE Antennas and Propagation Society, AP-S International Symposium (Digest) | Year: 2015

At the Department of Medical System Engineering, Chiba University, we have Electromagnetics (EM) as one of the fundamental subjects for the undergraduate students. This paper describes some features and problems of EM education for non-EE students at the Department. © 2015 IEEE.

Yashiro K.,Chiba University
Proceedings of the 2015 International Conference on Electromagnetics in Advanced Applications, ICEAA 2015 | Year: 2015

The scattering of E-polarlized plane wave from a finite array consisiting of perfect conductive and penetrable circular cylinders is analysed based on the method of moments with global basis functions and Galerkin approach. To do so, the surface impedance is introduced so that the boudary condition is imposed at the surfaces of all of cylinders in the unified manner. Some numerical examples are given. © 2015 IEEE.

Kondo K.,Chiba University
2015 10th Asian Control Conference: Emerging Control Techniques for a Sustainable World, ASCC 2015 | Year: 2015

Rotational sensorless control methods are one of the motor control methods with high performance and high reliability. One of the technical issued with the rotational speed sensorless controlled AC motors is to re-start their operation when inverters stop and the rotor speed or angle estimation. There several method to cope with the problems and they are reviewed in this paper. © 2015 IEEE.

Kakinuma Y.,Chiba University | Moriyama K.,Chiba University | Togo H.,Chiba University
Synthesis (Germany) | Year: 2013

Unsymmetrical diaryl ethers were efficiently obtained in good yields by the reactions of aryl(4-methoxyphenyl)iodonium tosylates with phenols, and aryl(2,4-dimethoxyphenyl)iodonium tosylates with phenols, in the presence of potassium carbonate in acetonitrile, respectively. The latter iodonium tosylates provided the corresponding unsymmetrical diaryl ethers in good yields with high regioselectivities, together with the quantitative formation of 1-iodo-2,4-dimethoxybenzene. © Georg Thieme Verlag Stuttgart New York.

Liu W.,Chiba University | Yamazaki F.,Chiba University
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2012

Shadows in remote sensing images often cause problems, especially in land-cover classification and change detection. Hence, it is very useful if the radiance of shadow areas is corrected to the same level as that of shadow-free areas. In this study, a radiance measurement was carried out to investigate the spectral characteristics of sunlight. Then a method is proposed for shadow detection and correction of optical imagery. First, building shadow areas are detected using an object-based classification method that employs brightness values and their relationship with the neighboring area. Next, the detected shadow areas are corrected using a linear function to produce a shadow-free image. The shadow pixels with different darkness levels are corrected by using different ratios to obtain a smoothly restored image. The proposed semi-automated method was applied to a QuickBird and a WorldView-2 images of Tokyo, Japan, to demonstrate the effectiveness of the method. © 2012 IEEE.

Sri Sumantyo J.T.,Chiba University | Shimada M.,Japan Aerospace Exploration Agency | Mathieu P.-P.,European Space Agency | Abidin H.Z.,Bandung Institute of Technology
IEEE Transactions on Geoscience and Remote Sensing | Year: 2012

In this paper, the long-term consecutive differential interferometric synthetic aperture radar (SAR) technique is used to measure the volume change during land deformation. This technique was used to investigate the subsidence of Bandung city, Indonesia, by assessing the data from two Japanese L-band spaceborne SARs (Japanese Earth Resources Satellite 1 SAR and Advanced Land Observation Satellite Phased Array type L-band Synthetic Aperture Radar) during the periods of 1993-1997 and 2007-2010. The results are confirmed using GPS observation data, ground survey data, local statistics, ground water level trend data, and the geological formation of the study area. The obtained results reveal a close correlation between the subsidence measurements and changes in the ground water level due to water pumping, population growth, industry growth, and urbanization of the study area. © 2011 IEEE.

Ashida H.,Tokyo Medical University | Mimuro H.,Tokyo International University | Sasakawa C.,Tokyo Medical University | Sasakawa C.,Nippon Institute for Biological Science | Sasakawa C.,Chiba University
Frontiers in Immunology | Year: 2015

The intestinal epithelium deploys multiple defense systems against microbial infection to sense bacterial components and danger alarms, as well as to induce intracellular signal transduction cascades that trigger both the innate and the adaptive immune systems, which are pivotal for bacterial elimination. However, many enteric bacterial pathogens, including Shigella, deliver a subset of virulence proteins (effectors) via the type III secretion system (T3SS) that enable bacterial evasion from host immune systems; consequently, these pathogens are able to efficiently colonize the intestinal epithelium. In this review, we present and select recently discovered examples of interactions between Shigella and host immune responses, with particular emphasis on strategies that bacteria use to manipulate inflammatory outputs of host-cell responses such as cell death, membrane trafficking, and innate and adaptive immune responses. © 2015 Ashida, Mimuro and Sasakawa.

Epidemiological evidence suggests there are significant links between obesity and obstructive sleep apnoea (OSA), with a particular emphasis on the importance of fat distribution in the development of OSA. In patients with OSA, the structure of the pharyngeal airway collapses. A collapsible tube within a rigid box collapses either due to decreased intraluminal pressure or increased external tissue pressure (i.e. reduction in transmural pressure), or due to reduction in the longitudinal tension of the tube. Accordingly, obesity should structurally increase the collapsibility of the pharyngeal airway due to excessive fat deposition at two distinct locations. In the pharyngeal airway region, excessive soft tissue for a given maxillomandibular enclosure size (upper airway anatomical imbalance) can increase tissue pressure surrounding the pharyngeal airway, thereby narrowing the airway. Even mild obesity may cause anatomical imbalance in individuals with a small maxilla and mandible. Lung volume reduction due to excessive central fat deposition may decrease longitudinal tracheal traction forces and pharyngeal wall tension, changing the 'tube law' in the pharyngeal airway (lung volume dependence of the upper airway). The lung volume dependence of pharyngeal airway patency appears to contribute more significantly to the development of OSA in morbidly obese, apnoeic patients. Neurostructural interactions required for stable breathing may be influenced by obesity-related hormones and cytokines. Accumulating evidence strongly supports these speculations, but further intensive research is needed. © 2011 Asian Pacific Society of Respirology.

Araki S.,Chiba University | Nakamura K.,Chiba University | Kobayashi K.,Chiba University | Tsuboi A.,Chiba University | Kobayashi N.,Chiba University
Advanced Materials | Year: 2012

A novel electrochromic device with three optical states, transparent, specular mirror, and black, is demonstrated. The cell is constructed by sandwiching gel electrolyte containing silver nitrate between one flat and one particle-modified indium thin oxide electrode. The optical states can be switched by altering the potential across the two electrodes. All changes are reversible and show good stability over 2500 cycles of testing. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Duhm S.,Chiba University | Xin Q.,Chiba University | Hosoumi S.,Chiba University | Fukagawa H.,Chiba University | And 4 more authors.
Advanced Materials | Year: 2012

The hole-phonon coupling of a rubrene monolayer on graphite is measured by means of angle resolved ultraviolet photoelectron spectroscopy. Thus, the charge reorganization energy λ and the small polaron binding energy is determined, which allows insight into the nature of charge transport in condensed rubrene. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ahn C.-J.,Chiba University
Recent Researches in Circuits, Systems, Control and Signals - Proceedings of the 2nd International Conference on Circuits, Systems, Control, Signals, CSCS'11 | Year: 2011

The electrical power generated by RF energy harvesting techniques is small, depending on techniques it is enough to drive low power consumption devices. Therefore, it is possible to increase the battery life and to reduce the environmental pollution. In this paper, we focus on the RF energy harvesting and design the rectenna with a 4×4 patch antenna of 2.13 GHz for low power mobile devices. The rectenna element is a microstrip patch antenna with PTFT board of 10 dielectric constant and 1.6 mm thick that has a gain of 5.8dBi. A step-up converter is adopted the Texas Instruments TPS61220. The step-up converter is operated with load at 0.7V to 5.5V. If the output current is 1.7mA, the conversion efficiency shows 80.9%. From the evaluated results of RF energy harvesting system, the low power mobile devices such as Zigbee when we set the distance of 12m can be operated.

Takeuchi N.,Chiba University | Nishiyama H.,Chiba University | Li Z.,Chinese Academy of Sciences
Annals of Glaciology | Year: 2010

Cryoconite granules are dark-colored spherical aggregates of organic and inorganic material on glacier ice, and are commonly observed on glaciers the world over. The structure of cryoconite granules on Ürümqi glacier No. 1, Tien Shan, China, was analyzed. Granules were distributed over the entire ice surface of the ablation area, and ranged in size from 0.26 to 3.5 mm (mean 1.1 mm). The granule surface was densely covered with filamentous cyanobacteria. Microscopy of a thin section revealed various inner structures. Most granules had concentric layers of dense organic matter, which are probably derived from annual growth of the granules by the activity of cyanobacteria. The number of layers averaged 3.5 and ranged up to 7, which is likely to indicate their mean and maximum growth ages, respectively. Some granules contained two or more subgranules, showing that small granules had combined and enlarged. Such structures suggest that granule formation was mainly due to the activity of filamentous cyanobacteria, and that the granules repeatedly grew and disintegrated over a cycle of several years on the glacier.

Nagase A.,Chiba University | Dunnett N.,University of Sheffield
Landscape and Urban Planning | Year: 2011

Choosing an appropriate substrate is one of the most important factors for green roofs because of their harsh growing environment. However, there have been few studies on the amount of organic matter necessary for sustainable plant growth in extensive green roofs. This study examined the relationship between percentage of organic matter in substrate and plant growth in extensive green roofs, particularly at establishment stage. Different percentages of organic matter (green waste compost: 0%, 10%, 25%, 50% by volume) were added and mixed well with a commercial green roof substrate (crushed brick base, containing less than 4% organic matter). Four species of plants (Allium schoenoprasum, Limonium latifolium, Melica ciliata and Nepeta×. faassenii) were grown in a greenhouse in trays containing substrates with these different percentages of organic matter. Two watering regimes were imposed: wet and dry (watering every 5 days or every 15 days). It was concluded that addition of 10% organic matter was optimal for these four species and the substrate used in this study because the plants showed stable growth regardless of the watering regime. In the wet regime, increased organic matter resulted in lush growth with may result in damage during drought. In the dry regime, increased organic matter did not result in increased growth. The response to higher organic matter content was different for different species, and species from a nitrogen-rich habitat tended to be encouraged by a high content. © 2011 Elsevier B.V.

Nobe A.,Chiba University
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2011

We present a tropical geometric description of a piecewise linear map whose invariant curve is a concave polygon. In contrast to convex polygons, a concave one is not directly related to tropical geometry; nevertheless the description is given in terms of the addition formula of a tropical elliptic curve. We show that the map arises from a pair of tropical elliptic pencils, each member of which is the invariant curve of an ultradiscrete QRT map. © 2011 Elsevier B.V. All rights reserved.

To remove and recover targeted ions and molecules at a high rate, inorganic compounds, enzymes, and extractants were immobilized onto a commercially available 6-nylon fiber by radiation-induced graft polymerization and subsequent chemical modifications. Fibrous supports with a smaller diameter provide a larger external interface area with liquids. Modified fibers are fabricated into various shapes such as wound filter and braid according to application sites. First, insoluble cobalt ferrocyanide-impregnated fiber was prepared via precipitation by immersing ferrocyanide ion-bound anion-exchange fiber in cobalt chloride solution. Cobalt ferrocyanide impregnated onto the polymer chain grafted onto the fiber specifically captured cesium ions in seawater. Similarly, sodium titanate impregnated onto a cation-exchange fiber selectively captured strontium ions in seawater. Second, urease was bound by an anion-exchange graft chain, followed by enzymatic cross-linking among urease molecules with transglutaminase. The bed charged with the urease-immobilized fiber exhibited a quantitative hydrolysis of urea at a high space velocity of urea solution. Third, an acidic extractant (HDEHP, bis(2-ethylhexyl) phosphate) was impregnated onto a dodecylamino-group-containing polymer chain grafted onto the 6-nylon fiber. Distribution coefficients of the HDEHP-impregnated fiber for neodymium and dysprosium agreed well with those in n-dodecane. © 2014, The Society of Polymer Science, Japan.

Gridnev I.D.,Tokyo Institute of Technology | Gridnev I.D.,Tohoku University | Liu Y.,Tohoku University | Imamoto T.,Chiba University
ACS Catalysis | Year: 2014

The mechanism of asymmetric hydrogenation of five representative β-dehydroamino acids catalyzed by rhodium complexes of (R)-(tert- butylmethylphosphino)(di-tert-butylphosphino)methane (trichickenfootphos, TCFP) and (R,R)-1,2-bis(tert-butylmethylphosphino)benzene (BenzP*) was studied through a combination of extensive NMR experiments and state-of-the-art DFT computations in order to reveal the crucial factors governing the sense and order of enantioselectivity in this industrially important reaction. The binding mode of the substrate with a Rh(I) catalyst was found to be highly dependent on the nature of the rhodium complex and the substrate. Thus, no substrate binding was detected for [Rh((R,R)-BenzP*)S2]+SbF 6- (5) and (E)-3-acetylamino-2-butenoate (2a) even at 173 K. [Rh((R)-TCFP) S2]+BF4- (3) exhibited weak reversible binding with 2a in the temperature interval 173-253 K with the formation of complex 4a, whereas at ambient temperature, slow isomerization of 2a to (Z)-3-acetylamino-2-butenoate (2b) took place. The investigations with a total of 10 combinations of the catalysts and substrates demonstrated various binding modes that did not affect significantly the enantioselectivities observed in corresponding catalytic reactions and in low temperature hydrogenations of the catalyst-substrate complexes. The monohydride intermediate 10 formed quantitatively when the equilibrium mixture of 2a, 3, and 4a was hydrogenated at 173 K. Its molecular structure including relative stereochemistry was determined by NMR experiments. These results together with the stereochemichal outcome of the low-temperature hydrogenation (99.2% ee, R) and DFT calculations led to the reasonable reaction pathway of the asymmetric hydrogenation of 2a catalyzed by 3. The conceivable catalytic pathways were computed for five combinations of the BenzP*-Rh catalyst and prochiral β-dehydroamino acids 2a,b and 21-23. In most cases, it was found that the pathways involving the hydrogenation of Rh(I) square planar chelate complexes are usually higher in free energy than the pathways with the hydrogen activation prior to the chelate formation. Computed differences in the free energies of the transition states for the double bond coordination stage of the R and S pathways reasonably well reproduce the optical yields observed experimentally in the corresponding catalytic reactions and in the low temperature hydrogenation experiments. To explain extremely high ee's (>99% ee) in some of the hydrogenations, it is necessary to analyze in more detail the participation of the solvent in the enantiodetermining step. © 2013 American Chemical Society.

Morikawa M.,Chiba University | Ahmed N.,Chiba University | Yoshida Y.,Chiba University | Izumi Y.,Chiba University
Applied Catalysis B: Environmental | Year: 2013

Photocatalytic reaction mechanism for the conversion of CO2 into methanol and CO using layered double hydroxides (LDHs) consisting of Zn, Cu, and Ga was investigated. X-ray absorption fine structure was applied to determine the LDH site structures and to monitor the diffusion of photogenerated electrons to CuII sites. Electron diffusion to Cu sites was an order of magnitude faster in the direction of the cationic layers (580μmolh-1gcat -1) than in the perpendicular direction. According to Fourier-transform infrared spectroscopy, CO2 was in equilibrium with hydrogen carbonate (1629cm-1 for H13CO3) for the reaction with hydroxy group from the cationic layer or interlayer site and/or with interlayer water. The equilibrium reactions were faster for [Zn3Ga(OH)8]+ 2[Cu(OH)4]2-·mH2O (400-110μmolh-1gcat -1) than for [Zn1.5Cu1.5Ga(OH)8]+ 2(CO3)2-·mH2O. Furthermore, the reductive decomposition of hydrogen carbonate was suggested in H2 under UV-visible light, suggesting photocatalytic pathway to methanol/CO. © 2013 Elsevier B.V.

Sasamoto T.,Chiba University | Spohn H.,TU Munich
Nuclear Physics B | Year: 2010

We consider the KPZ equation in one space dimension with narrow wedge initial condition, h(x,t=0)=-|x|/δ, δ≪1, evolving into a parabolic profile with superimposed fluctuations. Based on previous results for the weakly asymmetric simple exclusion process with step initial conditions, we obtain a determinantal formula for the one-point distribution of the solution h(x,t) valid for any x and t>0. The corresponding distribution function converges in the long time limit, t → ∞, to the Tracy-Widom distribution. The first order correction is a shift of order t-1/3. We provide numerical computations based on the exact formula. © 2010 Elsevier B.V.

Furuse T.,Red Cross | Hashimoto K.,Chiba University
Annals of General Psychiatry | Year: 2010

Background: Delirium is a highly prevalent disorder among older patients in intensive care units (ICUs). Although antipsychotic drugs are the medications most frequently used to treat this syndrome, these drugs are associated with a variety of adverse events, including sedation, extrapyramidal side effects, and cardiac arrhythmias. Drug treatment for delirium requires careful consideration of the balance between the effective management of symptoms and potential adverse effects.Methods: We report on five Japanese men (an 84 year old (acute aortic dissociation: Stanford type A), a 55 year old (traumatic subarachnoid hemorrhage and brain contusion), a 76 year old (sepsis by pyelonephritis), an 85 year old (cerebral infarction), and an 86 year old (pulmonary emphysema and severe pneumonia)) in which the selective serotonin reuptake inhibitor and sigma-1 receptor agonist fluvoxamine was effective in ameliorating the delirium of the patients.Results: Delirium Rating Scale (DRS) scores in these five patients dramatically decreased after treatment with fluvoxamine.Conclusion: Doctors should consider fluvoxamine as an alternative approach to treating delirium in ICU patients in order to avoid the risk of side effects and increased mortality from antipsychotic drugs. © 2010 Furuse and Hashimoto; licensee BioMed Central Ltd.

Minami Y.,Yokohama National University | Kurihara T.,University of Tokyo | Yamaguchi K.,University of Tokyo | Nakajima M.,Chiba University | Suemoto T.,University of Tokyo
Applied Physics Letters | Year: 2013

We introduce a simple and efficient method of enhancing the terahertz field in an air plasma produced by two-color laser pulses, by inserting a specially designed dual-wavelength wave plate between the non-linear optical crystal and the plasma. Adjusting the polarization of the two laser pulses yielded an electric field of 1.4 MV/cm, which was 1.7 times as intense as that obtained from the unmodified system. Additionally, taking a dispersion of the group velocities of the two-color laser pulses into account, we discussed the validity of the enhancement factor. © 2013 American Institute of Physics.

Ozen C.,Yale University | Ozen C.,Kadir Has University | Alhassid Y.,Yale University | Nakada H.,Chiba University
Physical Review Letters | Year: 2013

Heavy nuclei exhibit a crossover from vibrational to rotational collectivity as the number of neutrons or protons increases from shell closure towards midshell, but the microscopic description of this crossover has been a major challenge. We apply the shell model Monte Carlo approach to families of even-even samarium and neodymium isotopes and identify a microscopic signature of the crossover from vibrational to rotational collectivity in the low-temperature behavior of J2T, where J is the total spin and T is the temperature. This signature agrees well with its values extracted from experimental data. We also calculate the state densities of these nuclei and find them to be in very good agreement with experimental data. Finally, we define a collective enhancement factor from the ratio of the total state density to the intrinsic state density as calculated in the finite-temperature Hartree-Fock-Bogoliubov approximation. The decay of this enhancement factor with excitation energy is found to correlate with the pairing and shape phase transitions in these nuclei. © 2013 American Physical Society.

OBJECTIVES: Excessive stroma is a unique property of cancer tissue of the pancreas. The aim of this study was to analyze the relationship of cancer stromal area (SA) and tumor microvessel density (MVD) with prognostic and clinicopathological findings. METHODS: Pancreatic adenocarcinoma tissues obtained from 104 patients were subjected to cytokeratin 19 and CD31 double immunostaining to identify cancer cells and endothelial cells simultaneously. Stromal area and MVD were assessed in the same sections. Patients were divided into 2 groups for each analysis by the median value of the respective measure. RESULTS: Stromal area negatively correlated with MVD. The low SA group harbored more poorly differentiated carcinoma than the high SA group. Patients of the low SA group showed a higher incidence of hematogenous recurrence. As a consequence, patients in the low SA and the high MVD groups had poorer prognosis in terms of both disease-free survival and overall survival than their respective groups. Multivariate analysis showed that a low SA was an independent prognostic factor for disease-free and overall survival. CONCLUSIONS: Our data indicate that the stroma of pancreatic cancer may play an auxiliary role as a barrier to cancer cell invasion. The depletion of tumor stroma alone does not suppress pancreatic cancer progression. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

Kondo K.-I.,Chiba University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

In order to understand the so-called decoupling solution for gluon and ghost propagators in QCD, we give a nonperturbative construction of a massive vector field describing a non-Abelian massive spin-one particle, which has the correct physical degrees of freedom and is invariant under a modified Becchi-Rouet-Stora-Tyutin transformation, in a massive Yang-Mills model without the Higgs field, i.e., the Curci-Ferrari model. The resulting non-Abelian massive vector boson field is written by using a nonlinear but local transformation from the original fields in the Curci-Ferrari model. As an application, we write down a local mass term for the Yang-Mills field and a dimension-two condensate, which are exactly invariant under the modified Becchi-Rouet-Stora-Tyutin transformation, Lorentz transformation, and color rotation. © 2013 American Physical Society.

This paper reviews the reasons why plant factories with artificial light are recently interested in society, requirements for sustainable plant factories, the opportunities and challenges involved in the development of the technology and industry, and types of the plants suitable for plant factories with artificial light. Sustainable plant factories need to be designed and operated for producing high quality plants and transplants with minimum use of resource and minimum emissions of CO2 and environmental pollutants. For this purpose, the concept of "closed system" has been proposed, which is a structure with minimum ventilation, covered with thermally insulated opaque walls, containing multi-tiers (or racks) with artificial light sources. Advantages of this system over the greenhouse include: 1) culture period is shortened by 40-50% with uniform growth and high quality produce, 2) annual production capacity per floor area is 100-fold, and 3) percent reductions in resource consumption are considerable. For example, percent reduction is 100% for pesticide and 95% for irrigation water. Electricity consumption for producing one tomato transplant from a seed is about 300-400 kJ and its cost in Japan is about 1 JPY (0.008 Euro or 1 US cent as of 2011), and is 25 JPY for producing one butter head lettuce from a seed. Methods of developing integrative environmental control and reducing electricity consumption are discussed based mainly on theoretical consideration. Effects of environmental factors on the growth and development are beyond the scope of this paper.

Kitajima M.,Chiba University | Takayama H.,Chiba University
Topics in Current Chemistry | Year: 2012

Lycopodium alkaloids have attracted the attention of many natural product chemists and synthetic organic chemists due to their important biological activities and unique skeletal characteristics. In this review we describe isolation and asymmetric syntheses of several new alkaloids such as lycoposerramines-C,-V,-W, and cernuine, and show that asymmetric total synthesis played a key role in elucidating the structures of these complex natural products. © 2011 Springer-Verlag Berlin Heidelberg.

Tanaka K.,Tokyo Institute of Technology | Hanaoka M.,Chiba University
Frontiers in Plant Science | Year: 2012

The plastid signal was originally defined as a pathway that informs the nucleus of the chloroplast status and results in the modulation of expression of nuclear-encoded plastid protein genes. However, the transfer of chloroplast genes into the nuclear genome is a prerequisite in this scheme, although it should not have been established during the very early phase of chloroplast evolution. We recently demonstrated in a primitive red alga that the plastid-derived Mg-protoporphyrin IX activates nuclear DNA replication (NDR) through the stabilization of a G1 cyclin, which coordinates the timing of organelle and NDR. This mechanism apparently does not involve any transcriptional regulation in the nucleus, and could have been established prior to gene transfer events. However, a retrograde signal mediating light-responsive gene expression may have been established alongside gene transfer, because essential light sensing and regulatory systems were originally incorporated into plant cells by the photosynthetic endosymbiont. In this short article, we discuss the origins, early days and evolution of the plastid retrograde signal(s). © 2013 Tanaka and Hanaoka.

Ohfusa T.,Chiba University | Nishida A.,Chiba University
Tetrahedron | Year: 2011

Several bicyclic compounds were synthesized by the Diels-Alder reaction using aminodiene and a cyclic dienophile. The stereochemistries of the obtained adducts were determined by X-ray crystallography or NMR analysis. The stereoselectivity of this Diels-Alder reaction was based on the interaction of molecular orbitals between the diene and dienophile. The reactivities of these Diels-Alder reactions were estimated, and the generality of this reaction is discussed. © 2011 Elsevier Ltd. All rights reserved.

Minamino T.,Chiba University | Minamino T.,Japan Science and Technology Agency
Circulation Journal | Year: 2010

Epidemiological studies have shown that age is the chief risk factor for lifestyle-related diseases such as cardiovascular disease and diabetes, but the molecular mechanisms that underlie the increase in the risk of such diseases conferred by aging remain unclear. Recently, genetic analyses using various animal models have identified molecules that are crucial for aging. These include components of the DNA repair system, the tumor suppressor pathway, the telomere maintenance system, the insulin/Akt pathway, and other metabolic pathways. Interestingly, most of the molecules that influence the phenotypic changes of aging also regulate cellular senescence, suggesting a causative link between cellular senescence and aging. This review examines the hypothesis that cellular senescence might contribute to lifestyle-related disease.

Endo O.,Tokyo University of Agriculture and Technology | Nakamura M.,Chiba University | Amemiya K.,High Energy Accelerator Research Organization
Journal of Electron Spectroscopy and Related Phenomena | Year: 2013

Depth analysis using X-ray absorption fine-structure spectroscopy at the near carbon K-edge (C K-NEXAFS) was performed for self-assembled monolayers of 4-methylbenzenethiol (4-MBT) and 4-ethylbenzenethiol (4-EBT) on Au(1 1 1). On the basis of the polarization dependence of π* resonance intensity, the benzene rings of 4-MBT and 4-EBT were found to be tilted by 30 ± 10 and 60 ± 5 with respect to the Au(1 1 1) surface, respectively. The spectra were separated into two components according to their depth by fitting the intensity decay curves of the electrons emitted by X-ray absorption. The spectra for lower segments exhibited bands at almost identical energies with different intensities depending on the polarization between 4-MBT and 4-EBT. In contrast, the spectra for upper segments including the alkyl groups showed a marked difference in the location of the σCC* resonance. The σCC* resonance of the ethyl group predominantly observed in the 15 incidence spectrum of 4-EBT indicated that the ethyl group was directed perpendicularly. © 2013 Elsevier B.V.

Oohashi K.,Chiba University | Hirose T.,Japan Agency for Marine - Earth Science and Technology | Shimamoto T.,China Earthquake Administration
Journal of Geophysical Research: Solid Earth | Year: 2013

Graphite is a very low friction material, often enriched within fault zones due to mechanical or chemical processes. The effects of weak minerals on the strength of faults have been examined by friction experiments on bimineralic mixtures. However, previous experiments were conducted with limited shear strains, even though applied shear strains and textural developments had already been signaled as significant factors in the weakening of faults. We therefore conducted large-displacement, low- to high-velocity friction experiments with graphite-quartz gouges, to determine how much graphite is needed to reduce frictional strength, and to examine how textures contribute to the strength reduction of a mature fault at various slip rates. We found that the coefficients of friction of the gouges decrease nonlinearly with increasing graphite fraction for any given shear strain and slip rate, decreasing first with 5-20 vol% graphite, then reaching similar frictional levels to pure graphite with 30-50 vol% graphite. The nonlinear weakening trends can be fitted by sigmoidal curves. The weakening with 10-30 vol% graphite is associated with zones of slip-localization and the development of a graphite-lubricated penetrative slip surface(s). With increasing shear strain, the relationship between strength and graphite fraction evolves abruptly from an early gentle curve to a sigmoidal curve, and the frictional strength drops significantly even with small amounts of graphite (~10 vol%). Our results highlight the importance of shear strain and textural developments on weak faults, not only with respect to graphite, but also other fault lubricants such as the phyllosilicates. © 2013. American Geophysical Union. All Rights Reserved.

Ishida T.,Japan Institute for Molecular Science | Shirota H.,Chiba University
Journal of Physical Chemistry B | Year: 2013

The dynamical properties of a dicationic ionic liquid (IL), 1,6-bis(3-methylimidazolium-1-yl)hexane bis(trifluoromethylsulfonyl)amide ([C6(MIm)2][NTf2]2), compared to 1-methyl-3-propylimidazolium bis(trifluoromethylsulfonyl)amide ([C 3MIm][NTf2]), as its monocationic imidazolic counterpart, are studied by molecular dynamics simulations. We investigate relaxation processes of the polarizability anisotropy of the system and collective dynamics of both the ILs with mean-squared displacement (MSD), non-Gaussian parameter, and the intermediate scattering functions. The analyses of librational dynamics show that the difference of the Kerr spectra between the ILs could be mainly ascribed to the distinctive angular momentum of [C6(MIm) 2]2+ and [C3MIm]+ and related to the difference of relaxation behavior between [C6(MIm)2] 2+ and [C3MIm]+. Also, it is indicated that the librational dynamics of [NTf2]- indicate a common resonance-type sharp peak that corresponds to an intermolecular motion coupled to the vibrational mode intrinsic to [NTf2]-. In addition, it is exhibited from the total X-ray structure factors calculated for both of the ILs that the low-k peak at 0.20 Å-1 appears for [C 6(MIm)2][NTf2]2, while we do not see it for [C3MIm][NTf2]. We find that the contribution of the anion-cation and anion-anion correlations to the low-k peak is more significant than the cation-cation correlation. Therefore, it is suggested for [C6(MIm)2][NTf2]2 that dynamical heterogeneous behavior strongly correlates with structural variations or heterogeneity. © 2012 American Chemical Society.

Hoshino T.,Chiba University | Mahmood M.I.,Chiba University | Mori K.,Chiba University | Mori K.,Astellas Pharma Inc. | Matsuzaki K.,Kyoto University
Journal of Physical Chemistry B | Year: 2013

Accumulation and fibril formation of amyloid β (Aβ) peptides onto a ganglioside-rich lipid membrane is a cause of neuro-disturbance diseases. To find out a measure for suppressing the nucleation of a seed for amyloid fibrils, the mechanism of the initial binding of Aβ to the membrane should be clarified. Molecular dynamics simulations were carried out to investigate the adhesion process of Aβ peptides onto a GM1-ganglioside-containing membrane. Multiple computational trials were executed to analyze the probability of occurrence of Aβ binding by using calculation models containing a mixed lipid membrane, water layer, and one, two, or three Aβs. The simulations demonstrated that Aβ peptides approached the membrane after fluctuation in the water layer and occasionally made steady contact with the membrane. Once the steady contact had been established, Aβ was unlikely to be detached from the membrane and developed into a more stably bound form. In the stably bound form, neuraminic acids on the GM1 cluster strongly held the side chain of Lys28 of Aβ, which caused deformation of the C-terminal region of the Aβ. Since the C-terminal region of the Aβ peptide contains many hydrophobic residues, its deformation on the membrane enhances the hydrophobic interaction with other Aβ peptides. The contact region of two Aβs evolved into a parallel β-sheet form, and the third Aβ was observed to be bound to the complex of two Aβs to make a bundle of Aβ peptides. Some key structures involved in the Aβ aggregation on the GM1-containing membrane were deduced from the multiple simulations. © 2013 American Chemical Society.

Intermolecular/interionic vibrational spectra of mixtures composed of 1-methyl-3-n-octylimidazolium tetrafluoroborate ionic liquid and benzene at mole fractions of 0 (i.e., neat ionic liquid), 0.2, 0.4, 0.6, 0.8, and 1.0 (i.e., neat benzene) have been investigated using femtosecond Raman-induced Kerr effect spectroscopy. The line shape of the low-frequency Kerr spectra obtained from Fourier transform analyses of the Kerr transients is strongly dependent on the composition of the mixture. By comparing the experimental spectra to calculated spectra based on experimental spectra of the neat liquids, it is evident that the spectrum is not achieved by simply combining those of the neat liquids and taking the mole fraction into consideration. Close examination of the spectral comparison results in a microscopic picture involving specific stacking of imidazolium and benzene rings that is not sufficiently stable to affect the ring librations. The quantum chemistry calculation results also support this proposal. No clear correlation between the first moment of the spectrum and the bulk parameter (i.e., the square root of the surface tension divided by the liquid density), which occurs for neat liquids, is evident. © 2013 American Chemical Society.

Yoshida H.,Chiba University
Journal of Electron Spectroscopy and Related Phenomena | Year: 2015

Information about the unoccupied states is crucial to both fundamental and applied physics of organic semiconductors. However, there were no available experimental methods that meet the requirement of such research. In this review, we describe a new experimental method to examine the unoccupied states, called low-energy inverse photoemission spectroscopy (LEIPS). An electron having the kinetic energy lower than the damage threshold of organic molecules is introduced to a sample film, and an emitted photon in the near-ultraviolet range is detected with high resolution and sensitivity. Unlike the previous inverse photoemission spectroscopy, the sample damage is negligible and the overall resolution is a factor of two improved to 0.25. eV. Using LEIPS, electron affinity of organic semiconductor can be determined with the same precision as photoemission spectroscopy for ionization energy. The instruments including an electron source and photon detectors as well as application to organic semiconductors are presented. © 2015.

Nakamura K.,Chiba University | Kobayashi Y.,Chiba University | Kanazawa K.,Chiba University | Kobayashi N.,Chiba University
Journal of Materials Chemistry C | Year: 2013

A multifunctional composite film that exhibited thermoresponsive absorption and emission was fabricated using a thermochromic fluoran dye, its developer, and a luminescent europium(iii) complex. The emissions from and coloration of this composite film could be reversibly changed and maintained via the thermochromic reaction taking place within the fluoran dye-developer system. The coloration and decoloration of the composite film were caused by thermoresponsive control of the nanoscale aggregation of structures of the fluoran dye and its developer, whose molecular structure consisted of a long alkyl chain. The control of the phenomenon of photoluminescence could also be achieved via thermochromism, which was induced by intermolecular energy transfer from the Eu(iii) ions in the excited state to the fluoran dye. This journal is © 2013 The Royal Society of Chemistry.

Watanabe Y.,Chiba University | Nagashima T.,Chiba University | Nakamura K.,Chiba University | Kobayashi N.,Chiba University
Solar Energy Materials and Solar Cells | Year: 2012

We prepared solid-state electrochromic (EC) cells based on phthalate derivatives and containing a gel electrolyte. The cells showed vivid color changes via electrochemical reactions, i.e., from being water transparent to assuming one of the three primary colors (cyan, magenta, and yellow). Moreover, we obtained continuous-tone images by using the three primary-color EC cells. The formation of continuous-tone images by using the EC cells was realized by applying a rectangular-wave voltage with various duty ratios. In addition, according to a subtractive color-mixture process, we obtained multiple color representations, including intermediate red, green, and blue colors, by stacking two of the three primary-color EC cells. © 2012 Elsevier B.V. All rights reserved.

An understanding of the structure and behavior of electrolyte solutions in nanoenvironements is crucial not only for a wide variety of applications, but also for the development of physical, chemical, and biological processes. We demonstrate the structure and stability of electrolyte in carbon nanotubes using hybrid reverse Monte Carlo simulations of X-ray diffraction patterns. Hydrogen bonds between water are adequately formed in carbon nanotubes, although some hydrogen bonds are restricted by the interfaces of carbon nanotubes. The hydrogen bonding network of water in electrolyte in the carbon nanotubes is further weakened. On the other hand, formation of the ion hydration shell is significantly enhanced in the electrolyte in the carbon nanotubes in comparison to ion hydration in bulk electrolyte. The significant hydrogen bond and hydration shell formation are a result of gaining stability in the hydrophobic nanoenvironment. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Onochi Y.,Chiba University | Nakamura M.,Chiba University | Hoshi N.,Chiba University
Journal of Physical Chemistry C | Year: 2012

The dissolution of cubic and tetrahedral Pt nanoparticles has been studied on a Pt plate in 0.1 M NaClO 4 using conventional in situ atomic force microscopy (AFM). The Pt nanoparticles were dissolved during the potential cycle between 0.0 and 1.1 V (Ag/AgCl). The sides of the nanoparticles are dissolved faster than the upper parts. The height of cubic Pt nanoparticles does not change up to 200 cycles, shrinking to 80% of the initial height after 600 cycles. Tetrahedral Pt nanoparticles are dissolved from the top, forming a terrace at the upper part after 300 cycles. The durability of cubic Pt nanoparticles is higher than that of tetrahedral Pt nanoparticles. © 2012 American Chemical Society.

Arai T.,Chiba University | Sakagami K.,Chiba University
European Journal of Organic Chemistry | Year: 2012

Chiral, self-supported, polytopic imidazoline-pyridine ligands were designed and synthesized for use in Cu catalysis. The tripodal imidazoline-pyridine L6-Cu(BF 4) 2 complex catalyzed the asymmetric p-(tert-butyl)benzoylation of meso-hydrobenzoin to give the adduct in up to 85 % ee. After completion of the asymmetric benzoylation reaction, the self-supported tripodal imidazoline-pyridine-Cu catalyst could be easily recovered as a precipitate by adding hexane, and the recovered catalyst could be reused several times while maintaining the catalyst activity and selectivity. Chiral tripodal imidazoline-pyridine L6-Cu(BF 4) 2 complex catalyzed the asymmetric p-(tert-butyl)benzoylation of meso-hydrobenzoin to give the adduct in up to 85 % ee. After completion of the asymmetric benzoylation reaction, the self-supported tripodal imidazoline-pyridine-Cu catalyst was easily recovered and reused several times while maintaining the catalyst activity and selectivity. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nagase A.,Chiba University | Dunnett N.,University of Sheffield
Urban Forestry and Urban Greening | Year: 2013

Dwarf geophytes have great potential for use on extensive green roofs because they often come from arid areas and can survive dry and hot summer in a dormant state. However, there has been little research regarding geophytes on green roofs. This experiment was conducted to study the performance of 26 species of geophytes on a green roof during 2005-2006 in Sheffield, UK. The geophytes were grown at two substrate depths (5. cm and 10. cm) of substrate on a green roof without irrigation. To investigate the susceptibility of geophytes to competition from a covering of permanent plants, the geophytes were grown with or without a surface vegetation layer of Sedum album. Overall, the growth, survival rate, regeneration and flowering of geophytes were more successful at a substrate depth of 10. cm than of 5. cm, probably because of improved moisture retention, fewer temperature fluctuations and the protection from digging by animals. The flowering period was limited to spring, therefore, it is recommended to combine with other plant species such as covering plants. Geophyte species did not compete much with S. album and Sedum cover had no significant effects on the growth, survival rate, regeneration and flowering of geophytes in most species. Iris bucharica, Muscari azureum, Tulipa clusiana var. chrysantha, Tulipa humilis, Tulipa tarda and Tulipa turkestanica had good performance at the substrate depth of 5. cm. In addition, Narcissus cyclamineus 'February gold' and Tulipa urumiensis exhibited a successful performance at the substrate depth of 10. cm. © 2013 Elsevier GmbH.

Hitotsuyanagi A.,Chiba University | Nakamura M.,Chiba University | Hoshi N.,Chiba University
Electrochimica Acta | Year: 2012

The oxygen reduction reaction (ORR) have been studied on n(1 1 1)-(1 0 0) series of Pt using hanging meniscus rotating disk electrode (HMRDE) in 0.1 M HClO 4 (n is the number of terrace atomic rows). The activity for the ORR, which is estimated by the reduction current density at 0.90 V (RHE) j ORR,0.90 V, increases linearly with the increase of the step atom density d S on the surfaces with 5 ≤ n. On the surfaces with n < 5, however, the activity for the ORR decreases with the increase of d S. The deactivation of the ORR on the surfaces with n < 5 correlates with the formation of PtO-like species at the step. © 2012 Elsevier Ltd.

Watanabe Y.,Chiba University | Imaizumi K.,Chiba University | Nakamura K.,Chiba University | Kobayashi N.,Chiba University
Solar Energy Materials and Solar Cells | Year: 2012

We investigated the effect of counter electrode reaction on the coloration properties of phthalate-based electrochromic (EC) cells using various counter materials. Although the coloration characteristics of dimethyl terephthalate (DMT) cells were improved using a counter material of ferrocene, an organic-based counter material could not endure the overload because of the high reduction potential of DMT. On the other hand, a DMT cell using an inorganic counter material showed good long-term switching stability. As a result, we achieved good switching stability over 5000 cycles for the phthalate-based EC cell with NiO as the counter material. © 2011 Elsevier B.V. All rights reserved.

Ohba T.,Chiba University | Kanoh H.,Chiba University | Kaneko K.,Nagano University
Journal of Physical Chemistry C | Year: 2012

We demonstrate a water penetration mechanism through zero-dimensional nanogates of a single-walled carbon nanohorn. Water vapor adsorption via the nanogates is delayed in the initial adsorption stage but then proceeds at a certain rate. The mechanism is proposed to be a water cluster-chain-cluster transformation via the nanogates. The growth of water clusters in internal nanospaces facilitates water penetration into these nanospaces, providing an intrinsic mechanism for zero-dimensional water. © 2012 American Chemical Society.

Arai S.,Chiba University | Koike Y.,Chiba University | Hada H.,Chiba University | Nishida A.,Chiba University
Journal of the American Chemical Society | Year: 2010

A palladium-catalyzed dicyanative [4+2] cycloaddition reaction using dienynes with TMSCN under aerobic conditions is described. This new reaction triggered by the cyanopalladation of terminal alkynes includes regioselective direct cyanation to C-C triple bonds by TMSCN to give --allyl Pd intermediates, which promotes 5- exo followed by 6- endo cyclization. This protocol enables (1) the formation of four C-C bonds through one operation, (2) the construction of highly functionalized cyclohexene rings, and (3) the generation of five contiguous stereogenic centers in one operation. The intermolecular cycloaddition reaction between a conjugated enyne and methyl acrylate also proceeded in a regioselective fashion to give multifunctionalized carbocycles. © 2010 American Chemical Society.

Arai S.,Chiba University | Koike Y.,Chiba University | Nishida A.,Chiba University
Advanced Synthesis and Catalysis | Year: 2010

A stereoselective dicyanative 5-exo- and 6endo-cyclization using various enynes has been investigated. The mode of cyclization is critically controlled by the structure of the substrates. For example, N-allyl derivatives prefer 5-exo-cyclization, while methacryloyl amides are transformed to the corresponding lactams with tetra substituted carbons at the alpha-position via 6-endo-cyclization. Both reactions include syn-cyanopalladation to carbon≡carbon triple bonds in the initial step, and sequential cyclization followed by reductive elimination in one operation enables the construction of the highly functionalized nitrogen heterocycles. The scope of suitable substrates and a proposed mechanism are also described. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.

Igarashi K.,Chiba University | Kashiwagi K.,Chiba Institute of Science
Molecular Nutrition and Food Research | Year: 2011

The relationship between acrolein (CH 2=CH-CHO) and brain infarction is the focus of this review. It has been found that acrolein is produced mainly within cells from polyamines by polyamine oxidases (PAOs), especially from spermine by spermine oxidase during cell damage, and that acrolein is more toxic than reactive oxygen species (ROS) in a cell culture system. Thus, the possibility that acrolein and PAOs are good biochemical markers of stroke was tested because there are no other reliable biochemical markers at the early stage of stroke. Levels of protein-conjugated acrolein (PC-Acro) and PAOs (acrolein-producing enzymes) were significantly increased in the plasma of stroke patients. The multiplied value of PC-Acro by PAOs was nearly parallel with the size of stroke. Furthermore, when the combined measurements of PC-Acro, interleukin-6 (IL-6) and C-reactive protein (CRP) were evaluated along with age using a receiver operating characteristic (ROC) curve, even silent brain infarction (SBI), which is a small brain infarction, was indicated with approximately 84% sensitivity and specificity. These findings clearly indicate that acrolein is strongly correlated with cell damage during brain infarction. © 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.

Tagata T.,Chiba University | Tagata T.,Koei Chemical Company | Nishida M.,Koei Chemical Company | Nishida A.,Chiba University
Advanced Synthesis and Catalysis | Year: 2010

A new continuous-flow system for C-H borylation has been developed. An insoluble catalyst prepared from chloro(1,5-cyclooctadien)iridium(I) dimer and 2,2′-bipyridine-4,4′-dicarboxylic acid in the presence of bis(pinacolato)diboron exhibited high reactivity under continuous-flow processing without the loss of expensive iridium metal. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Suzuki K.,Chiba University | Matsubara H.,Chiba University
Journal of Biomedicine and Biotechnology | Year: 2011

TP53, encoding p53, is one of the most famous tumor suppressor genes. The majority of human cancers demonstrate the inactivation of the p53 pathway. Mutant p53 not only, no longer, functions as a tumor suppressor but can also exert tumor-promoting effects. The basic function of p53 is to respond to cellular stress. We herein review the recent advances in p53 research and focus on apoptosis, cell cycle arrest, and senescence in response to stress. We also review the clinical applications of p53-based therapy for human cancer. Copyright © 2011 Kazufumi Suzuki and Hisahiro Matsubara.

Tao Y.,Shinshu University | Muramatsu H.,Shinshu University | Endo M.,Shinshu University | Kaneko K.,Chiba University
Journal of the American Chemical Society | Year: 2010

(Graph Presented) Highly pure double-walled carbon nanotubes synthesized by a catalytic chemical vapor deposition method have a quasi one-dimensional nanopore system. We determined these nanotubes' nanopore structures by means of molecular probe adsorption using N2 at 77 K, CO2 at 273 K, and water at 298, 308, and 318 K, as well as high-resolution transmission electron microscopy. The water vapor adsorption behavior of this system was quite unusual. At a lower relative pressure of P/P0 = 0.3-0.65, water filled the interstitial nanopores, and at relative pressures higher than this range, water also filled the interbundle nanopores. This study is the first to our knowledge that has provided direct evidence of water adsorption in hydrophobic nanospaces of highly pure double-walled carbon nanotubes. Copyright © 2010 American Chemical Society.

Arai T.,Chiba University | Taneda Y.,Chiba University | Endo Y.,Chiba University
Chemical Communications | Year: 2010

A diastereoselective Henry reaction of chiral aldehydes with nitroalkanes was developed using a chiral sulfonyldiamine (L1)-CuCl complex. The reaction of (R)-2-phenylpropanal and nitromethane was smoothly catalyzed by the (S,S,S)-L1-CuCl complex to give the adduct with 99/1 syn/anti selectivity in 99% ee. In the reaction of (S)-2-phenylpropanal and nitroethane, the (R,R,R)-L1-CuCl catalyst yielded the expected three contiguous stereogenic centers in a highly syn-selective Henry reaction. © 2010 The Royal Society of Chemistry.

Fujimori T.,Chiba University | Urita K.,Nagasaki University | Ohba T.,Chiba University | Kanoh H.,Chiba University | Kaneko K.,Chiba University
Journal of the American Chemical Society | Year: 2010

Surface-enhanced Raman scattering (SERS) was applied to detecting pentagon-heptagon pairs, the so-called Stone-Wales defect, in single-wall carbon nanotubes (SWCNTs). When a probing laser light was scanned over a SWCNT-dispersed silver surface, two distinct SERS spectra were obtained: (1) temporally stable spectra similar to that of resonance Raman spectra of bulk SWCNTs and (2) temporally fluctuating spectra with additional peaks which were not observed in the non-SERS spectra. The fluctuations in the SERS spectra are discussed in association with dynamic reconstruction of defective structures of SWCNTs (nonhexagonal arrangements of carbon atoms) in the vicinity of SERS-active sites under irradiation of the laser light. © 2010 American Chemical Society.

Yagai S.,Chiba University | Yagai S.,Chiyoda Corporation | Iwai K.,Chiba University | Karatsu T.,Chiba University | Kitamura A.,Chiba University
Angewandte Chemie - International Edition | Year: 2012

Light on: Photocontrol of J-type exciton interactions by using chromophores is reported (see picture). Hydrogen-bonded merocyanine dyes could be switched reversibly through photoinduced ring-closure/ring-opening reactions of diarylethene receptors. Addition of H-aggregation-inducing bismelamine receptors enabled the partial interconversion between J- and H-type exciton coupling. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yagishita F.,Chiba University | Ishikawa H.,Chiba University | Onuki T.,Chiba University | Hachiya S.,Chiba University | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

Preferential crystallization is a powerful tool to obtain optically active materials from racemic mixtures without any chiral source, and has been utilized widely for optical resolution on large scales for example in industrial processes.[ 1] To resolve optically active materials by crystallization efficiently, dynamic preferential crystallization involving a racemization process, a so-called total spontaneous resolution, has been developed.[2] Many efforts have been invested in new variations of this method, and the racemization processes can be classified into three groups: 1) involving an intermediate enolate anion or enol at the a-position of a carbonyl group,[3] 2) involving atropisomerism of axially chiral materials,[4] and 3) involving an equilibrium reaction via an achiral intermediate.[5-7] We have now developed a new example of total spontaneous resolution of isoindolinones that involves a combination of an intramolecular equilibrium reaction via an achiral intermediate and preferential crystallization. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ahn C.-J.,Chiba University
Proceedings of 2015 2nd National Foundation for Science and Technology Development Conference on Information and Computer Science, NICS 2015 | Year: 2015

The majority of people in the world lack access to the Internet. Google proposed the project Loon being developed for providing internet access to remote and rural areas. The project considers solar power for high-altitude balloons. However, the usage of solar power is limited due to time and place. Previously, we have developed the prototype of 5.8 GHz wireless power transmission system with high performance rectenna for an electric vehicle system. By using this experience, we have developed the rough beamforming method based 5.8 GHz wireless power transmission system for high-altitude balloons such as project Loon. In this paper, we describe the developed the rough beamforming method based 5.8 GHz wireless power transmission system. From the measurement results, beamforming phased array antenna can transmit power more efficiently compared with a horn antenna and array antenna without beamforming with increasing the transmission distance. For transmission distance of 1000mm, beamforming phased array antenna can receive the power about 1.46 times compared with array antenna without beamforming. © 2015 IEEE.

Abe A.,Chiba University
Proceedings - IEEE 13th International Conference on Data Mining Workshops, ICDMW 2013 | Year: 2013

According to the wide development of the World Wide Web world, many peoples have tend to mention 'big data'' and tried to make use of the 'big data.' They usually mention 'big data'' as a key to the happy future. However, it will be a dream which will not be realized. In this paper, I review problems in big data. Then I propose a concept of curation to deal with such big and complex data. © 2013 IEEE.

Sakao S.,Chiba University | Tatsumi K.,Chiba University
Respirology | Year: 2011

It is generally accepted that genetic predisposition plays a role in COPD development in susceptible individuals. Therefore, many candidate genes that could be linked to the development of disease have been examined in COPD. However, inconsistent results in different study populations often limit this approach, suggesting that not only genetics, but also other factors, may be contributed to the susceptibility to COPD. Epigenetic mechanisms can affect the transcriptional activity of specific genes, at different points in time, and in different organs. Moreover, these mechanisms can have an effect on people's health. Recently, there is emerging evidence supporting a role of epigenetics for the regulation of inflammatory genes in diseases such as asthma and COPD. Moreover, recent studies suggest that the currently used treatments including corticosteroids may work through epigenetic mechanisms. Epigenetic regulation can be reprogrammed, potentially affecting the risk, aetiology and treatment of various disease states. The epigenetically influenced phenotype could be reversed with demethylating or deacetylating agents, consistent with epigenetic plasticity. The postnatal reversibility of these methylation or acetylation events may therefore provide good opportunities for intervention. The recognition of the role of genetic and epigenetic mechanisms in the development of COPD may identify novel targets that hatch new therapies for patients with COPD. © 2011 Asian Pacific Society of Respirology.