Aichi University of Education
Kariya, Japan

Aichi University of Education is a national university at Kariya, Aichi, Japan, founded in 1949. Wikipedia.

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Taguchi M.,Aichi University of Education
Journal of Geophysical Research: Atmospheres | Year: 2017

Climatological frequency of major stratospheric sudden warmings (MSSWs) during northern winter has been repeatedly investigated using model simulations, but its model-to-model differences are relatively unexplained. Using an archive of the Coupled Model Intercomparison Project Phase 5 (CMIP5) historical simulations with 30 models, this study investigates the MSSW frequency of the simulations by building a framework in which the frequency is decomposed into a few factors. Results first demonstrate that the multimodel differences in the MSSW frequency are closely related to the mean and variability of the zonal mean zonal wind in the extratropical stratosphere in each simulation. An important point is that for each simulation, the zonal wind variability is further represented by a combination, or product, of average strength of extreme transient planetary wave forcings from the troposphere and average deceleration response of the polar vortex to an extreme wave forcing of fixed strength. This product can be interpreted and used as a proxy of large-scale dynamical variability of the polar vortex arising from the planetary wave-mean flow interaction. It turns out that a large portion of the CMIP5 model simulations underestimate one or both of the factors, leading to underestimations in dynamical variability. This contributes to the general underestimation of MSSW frequency in the simulations. This study proposes that this framework can be used in general to better understand MSSW frequency in different models and climate conditions (e.g., future climate change). © 2017. American Geophysical Union. All Rights Reserved.

Mizutani U.,Nagoya Industrial Science Research Institute | Inukai M.,Toyota Technological Institute | Sato H.,Aichi University of Education | Zijlstra E.S.,University of Kassel
Chemical Society Reviews | Year: 2012

Full-potential linearized augmented plane wave (FLAPW) electronic band calculations were performed for two RT- (rhombic triacontahedron) and five MI- (Mackay icosahedron) type 1/1-1/1-1/1 approximants plus several complex metallic compounds in Al-TM (TM = transition metal element) binary alloy systems in order to elucidate the origin of a pseudogap from the viewpoint of Fermi surface-Brillouin zone (FsBz) interactions. The square of the Fermi diameter (2k F) 2 and square of the critical reciprocal lattice vector G 2 or the critical set of lattice planes, with which electrons at the Fermi level E F are interfering, can be extracted from the FLAPW-Fourier method. We revealed that a pseudogap in both RT- and MI-type 1/1-1/1-1/1 approximants universally originates from interference phenomenon satisfying the matching condition (2k F) 2 = G 2 equal to 50 in units of (2π/a) 2, where a is the lattice constant. The multi-zone effect involving not only G 2 = 50 but also its neighboring ones is also claimed to be responsible for constituting a pseudogap across E F. The value of e/a for Mn, Fe, Re and Ru elements in the periodic table is deduced to be positive in the neighborhood of unity. All 1/1-1/1-1/1 approximants, regardless of RT- or MI-type atomic cluster involved, are stabilized at around e/a= 2.7, while their counterpart quasicrystals are at around e/a= 2.2. A new Hume-Rothery electron concentration rule linking the number of atoms per unit cell, e/uc, with a critical G 2 holds well for all complex intermetallic compounds characterized by a pseudogap at E F. © 2012 The Royal Society of Chemistry.

Kano T.,Kyoto University | Shirozu F.,Kyoto University | Akakura M.,Aichi University of Education | Maruoka K.,Kyoto University
Journal of the American Chemical Society | Year: 2012

Di-tert-butyl methylenemalonate (1) could be employed as a reactive equivalent of a three-carbon Michael acceptor such as acrylate in a direct asymmetric conjugate addition of aldehydes catalyzed by an axially chiral amino diol (S)-3a. Furthermore, acrylate, an unexplored and challenging substrate in enamine catalysis, has also been successfully employed in asymmetric conjugate addition reaction. Relatively inert acrylate is doubly activated by polyfluoroalkyl group of 2 and the hydroxyl group on the axially chiral amino diol catalyst (S)-3b, giving corresponding conjugate adducts in high yield with excellent enantiomeric excess. The obtained conjugate addition products were readily converted to synthetically useful and important chiral building blocks. © 2012 American Chemical Society.

Kano T.,Kyoto University | Sakamoto R.,Kyoto University | Akakura M.,Aichi University of Education | Maruoka K.,Kyoto University
Journal of the American Chemical Society | Year: 2012

The 1,2-diamine (vicinal diamine) motif is present in a number of natural products with interesting biological activity and in many chiral molecular catalysts. The efficient and stereocontrolled synthesis of enantioenriched vicinal diamines is still a challenge to modern chemical methodology. We report here both syn- and anti-selective asymmetric direct Mannich reactions of N-protected aminoacetaldehydes with N-Boc-protected imines catalyzed by proline and the axially chiral amino sulfonamide (S)-3. This organocatalytic process represents the first example of a Mannich reaction using Z- or Boc-protected aminoacetaldehyde as a new entry of α-nitrogen functionalized aldehyde nucleophile in enamine catalysis. The obtained optically active vicinal diamines are useful chiral synthons as exemplified by the formal synthesis of (-)-agelastatin A. © 2012 American Chemical Society.

Taguchi M.,Aichi University of Education
Atmospheric Science Letters | Year: 2016

This study explores a possible connection between predictability variations of major stratospheric sudden warmings (MSSWs) during Northern winter and the geometry of the polar vortex. We compare 1-month hindcasts from 1979 to 2012 of the Japan Meteorological Agency to the Japanese 55-year Reanalysis data. Results show that error variations of medium range (≈14day) forecasts of 21 actual MSSWs do depend on the observed geometry of the polar vortex: the errors are larger for vortex split MSSWs when the polar vortex is highly stretched as characterized by a high aspect ratio and an amplified zonal wavenumber 2 component. © 2016 Royal Meteorological Society.

Nagao S.,Aichi University of Education | Yamaguchi T.,Aichi University of Education
Current Molecular Pharmacology | Year: 2012

Autosomal dominant polycystic kidney disease (ADPKD) is the most common of the monogenic disorders and is characterized by bilateral renal cysts; cysts in other organs including liver, pancreas, spleen, testis and ovary; vascular abnormalities including intracranial aneurysms and subarachnoid hemorrhage; and cardiac disorders such as left ventricular hypertrophy (LVH), mitral valve regurgitation, mitral valve prolapse and aortic regurgitation. Autosomal recessive polycystic kidney disease (ARPKD) is an early-onset multisystem disorder characterized by polycysts divided from the renal collecting ducts, congenital hepatic fibrosis, and ductal plate malformation complicated by pulmonary hyperplasia and systemic hypertension. In these polycystic kidney diseases (PKD), progressive enlargement of the cysts results from the aberrant proliferation of tubule epithelial cells and trans-epithelial fluid secretion leading to extensive nephron loss and interstitial fibrosis. Peroxisome proliferator-activated receptor-γ (PPAR-γ), a member of the liganddependent nuclear receptor superfamily, is expressed in a variety of tissues, including kidneys and liver, and plays important roles in cell proliferation, fibrosis, and inflammation. PPAR-γ agonists ameliorate polycystic kidney, polycystic liver and cardiac defects through β-catenin, c-Myc, CFTR, MCP-1, S6, ERK, and TGF-β signaling pathways in animal models of PKD. In this review, we describe the possible therapeutic value of PPAR-γ agonists in the treatment of renal and hepatic manifestations, and cardiac defects in progressive PKD. © 2012 Bentham Science Publishers.

Taguchi M.,Aichi University of Education
Journal of Geophysical Research: Atmospheres | Year: 2010

Using a stratospheric zonal wind data archive of radiosonde observations at equatorial stations for 1953-2008, this study investigates whether or not signals of the quasi-biennial oscillation (QBO) vary with the El Niño-Southern Oscillation (ENSO) cycle. The signals of the QBO are represented by trajectories in a phase space spanned by time series of two leading modes of wind variability. Two properties of the trajectories, distance from the origin and time rate of change in argument, which are proxies for amplitude and phase progression rate of the QBO, respectively, are first examined in relation to seasons and QBO phases. The examination confirms known features of the QBO including the so-called seasonal locking and more regular phase propagation for the westerly phase. A further comparison of the properties between cold and warm ENSO conditions (La Niña and El Niño, respectively) reveals unprecedented evidence of clear variations of the QBO with ENSO: the QBO signals exhibit weaker amplitude and faster phase propagation for El Niño conditions. Such variations are also supported by a composite analysis of zonal wind anomalies. We also discuss a possible connection of the ENSO-associated changes in the QBO with those in equatorial wave activity. Copyright 2010 by the American Geophysical Union.

This study investigates the predictability of three major stratospheric sudden warmings (MSSWs) of the vortex split type: the Southern Hemisphere case in September 2002 and two Northern Hemisphere cases in January 2009 and February 1989. The author examines changes in the predictability of the MSSWs with lead time, as well as the connection of the predictability to lower-atmospheric features for pre- and post-MSSW periods. The Japan Meteorological Agency (JMA)'s 1-month ensemble hindcast (HC) experiment data are compared to the Japanese 25-year Reanalysis Project (JRA-25)/JMA Climate Data Assimilation System (JCDAS) data. For the pre-MSSW period, a strong predictability connection is observed among all three cases. Unsuccessful predictions of the MSSWs are characterized by an underestimation (or lack) of the enhanced wave activity in the lower stratosphere, which is further related to the strength and persistence of the uppertropospheric ridge and trough. The mean zonal wind profile in the upper troposphere is also important for the 2009 case. These results confirm the role of tropospheric wave forcing of the MSSWs in the context of predictability. The characteristic time scale for successful predictions is approximately 10 days-2 weeks, which roughly corresponds to the time scale of the tropospheric wave forcing. No ensemble member successfully predicts the MSSWs with lead times longer than the time scale. The predictability connection between the stratospheric and tropospheric anomalies is more subtle for the post-MSSW period. In particular, the HC group initialized about 1 week before the MSSWs tends to reproduce the evolution of the stratosphere after the MSSWs well but not that of the troposphere in some cases. © 2014 American Meteorological Society.

Kasuga N.,Aichi University of Education
Histochemistry and Cell Biology | Year: 2011

The recruitment of satellite cells, which are located between the basement membrane and the plasma membrane in myofibers, is required for myofiber repair after muscle injury or disease. In particular, satellite cell migration has been focused on as a satellite cell response to muscle injury because satellite cell motility has been revealed in cell culture. On the other hand, in situ, it is poorly understood how satellite cell migration is involved in muscle regeneration after injury because in situ it has been technically very difficult to visualize living satellite cells localized within skeletal muscle. In the present study, using quantum dots conjugated to anti-M-cadherin antibody, we attempted the visualization of satellite cells in both intact and injured skeletal muscle of rat in situ. As a result, the present study is the first to demonstrate in situ real-time imaging of satellite cells localized within the skeletal muscle. Moreover, it was indicated that satellite cell migration toward an injured site was induced in injured muscle while spatiotemporal change in satellite cells did not occur in intact muscle. Thus, it was suggested that the satellite cell migration may play important roles in the regulation of muscle regeneration after injury. Moreover, the new method used in the present study will be a useful tool to develop satellite cell-based therapies for muscle injury or disease. © 2010 Springer-Verlag.

Saadi J.,University of Chicago | Akakura M.,Aichi University of Education | Yamamoto H.,University of Chicago
Journal of the American Chemical Society | Year: 2011

The Mukaiyama cross-aldol reaction of α-fluoro-, α-chloro-, and α-bromoacetaldehyde-derived (Z)-tris(trimethylsilyl)silyl enol ethers is described, furnishing anti-β-siloxy-α-haloaldehydes. A highly diastereoselective, one-pot, sequential double-aldol process is developed, affording novel β,δ-bissiloxy-α,γ-bishaloaldehydes. Reactions are catalyzed by C 6F 5CHTf 2 and C 6F 5CTf 2AlMe 2 (0.5-1.5 mol %) and provide access to halogenated polyketide fragments. © 2011 American Chemical Society.

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