81 research outputs found

    Bismuth coordination networks containing deferiprone: synthesis, characterisation, stability and antibacterial activity

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    A series of bismuth–dicarboxylate–deferiprone coordination networks have been prepared and structurally characterised. The new compounds have been demonstrated to release the iron overload drug deferiprone on treatment with PBS and have also been shown to have antibacterial activity against H. pylori

    日本の大学における英語アカデミックライティング教育の可能性と課題

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    Today, whether English's dominance as a global lingua franca benefits higher education, more and more universities around the world have made efforts to integrate English academic writing education into their institutional policies and strategies. This trend has been observed particularly against the background where, with the increased internationalization of higher education, the imperative for universities globally to focus on maintaining or improving their international reputation and rankings has grown significantly. Indeed, such prestige tends to be assessed largely in terms of publications in English. With this in mind, we are concerned with how higher education institutions address these efforts toward promoting English academic writing in a specific non-English L1 context, namely Japan. English academic writing in university contexts where English is an additional language exists where the fields of language education, higher education administration, research methodology, and cultural socialization converge. Therefore, this volume brings together scholarship that aims to examine the different ways in which academic writing education shapes and is shaped by students, faculty and other stakeholders in Japanese universities. This volume’s eight chapters, by authors with diverse backgrounds, ranging from administrators to researchers, and from humanities and social sciences to medical studies, explore the opportunities and challenges of English academic writing education in Japanese universities by looking at related topics, including writing centers, faculty members, genre-specific education, and technology development. Together, the discussions in the individual chapters can contribute profoundly to theory, policy, and practice in the domains of curriculum, research, and administration in university contexts.Introduction… Norifumi Miyokawa 1 Part I: A writing center in Japan: Hiroshima University Chapter One: Development of the Hiroshima University Writing Center -From an administrative perspective-… Hiroko Araki & Norifumi Miyokawa 3 Chapter Two: Perceptions of academic writing support -A needs analysis of the Hiroshima University Writing Center-… Roehl Sybing & Norifumi Miyokawa 17 Part II: Faculty development for academic writing Chapter Three: Potential roles of writing centers for writing related Faculty Development… Machi Sato & Shinichi Cho 31 Chapter Four: Academic writing support for faculty members -Writing Groups and Writing Retreats-… Adina Staicov 45 Part III: Genre-specific education: Cases in the medical field Chapter Five: How to write the Introduction of biomedical research articles -Move analysis of the first and last sentences-… Takeshi Kawamoto & Tatsuya Ishii 57 Chapter Six: Error analysis of overt lexicogrammatical errors in the prepublication English-language manuscripts of Japanese biomedical researchers -With implications for the teaching of writing for biomedical research –… Flaminia Miyamasu 67 Part IV: Theoretical and practical approaches to academic writing Chapter Seven: Language socialization and writing centers… Akiko Katayama 81 Chapter Eight: Socialization into integrity -Using plagiarism software to teach L2 writing-… Gavin Furukawa 95 Acknowledgements… Norifumi Miyokawa 10

    Porous colloidal hydrogels formed by coordination-driven self-assembly of charged metal-organic polyhedra

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    Introduction of porosity into supramolecular gels endows soft materials with functionalities for molecular encapsulation, release, separation and conversion. Metal-organic polyhedra (MOPs), discrete coordination cages containing an internal cavity, have recently been employed as building blocks to construct polymeric gel networks with potential porosity. However, most of the materials can only be synthesized in organic solvents, and the examples of porous, MOP-based hydrogels are scarce. Here, we demonstrate the fabrication of porous hydrogels based on [Rh2(OH-bdc)2]12, a rhodium-based MOP containing hydroxyl groups on its periphery (OH-bdc=5-hydroxy-1,3-benzenedicarboxylate). By simply deprotonating [Rh2(OH-bdc)2]12 with the base NaOH, the supramolecular polymerization between MOPs and organic linkers can be induced in the aqueous solution, leading to the kinetically controllable formation of hydrogels with hierarchical colloidal networks. When heating the deprotonated MOP, Nax[Rh24(O-bdc)x(OH-bdc)24-x], to induce gelation, the MOP was found to partially decompose, affecting the mechanical property of the resulting gels. By applying a post-synthetic deprotonation strategy, we show that the deprotonation degree of the MOP can be altered after the gel formation without serious decomposition of the MOPs. Gas sorption measurements confirmed the permanent porosity of the corresponding aerogels obtained from these MOP-based hydrogels, showing potentials for applications in gas sorption and catalysis

    Improving the gas sorption capacity in lantern-type metal-organic polyhedra by a scrambled cage method

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    The synthesis of multivariate metal-organic frameworks (MOFs) is a well-known method for increasing the complexity of porous frameworks. In these materials, the structural differences of the ligands used in the synthesis are sufficiently subtle that they can each occupy the same site in the framework. However, multivariate or ligand scrambling approaches are rarely used in the synthesis of porous metal-organic polyhedra (MOPs) – the molecular equivalent of MOFs – despite the potential to retain a unique intrinsic pore from the individual cage while varying the extrinsic porosity of the material. Herein we directly synthesise scrambled cages across two families of lantern-type MOPs and find contrasting effects on their gas sorption properties. In one family, the scrambling approach sees a gradual increase in the BET surface area with the maximum and minimum uptakes associated with the two pure homoleptic cages. In the other, the scrambled materials display improved surface areas with respect to both of the original, homoleptic cages. Through analysis of the gas sorption isotherms, we attribute this effect to the balance of micro- and mesoporosity within the materials, which varies as a result of the scrambling approach. The gas uptake of the materials presented here underscores the tunability of cages that springs from their combination of intrinsic, extrinsic, micro- and meso- porosities

    Porous metal-organic cages based on rigid bicyclo[2.2.2]oct-7-ene type ligands : synthesis, structure, and gas uptake properties

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    Three new ligands containing a bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxydiimide unit have been used to assemble lantern-type metal-organic cages with the general formula [Cu4L4]. Functionalisation of the backbone of the ligands leads to distinct crystal packing motifs between the three cages, as observed with single-crystal X-ray diffraction. The three cages vary in their gas sorption behaviour, and the capacity of the materials for CO2 is found to depend on the activation conditions: softer activation conditions lead to superior uptake, and one of the cages displays the highest BET surface area found for lantern-type cages so far

    A peculiar jet and arc of molecular gas toward the rich and young stellar cluster Westerlund 2 and a TeV gamma ray source

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    We have discovered remarkable jet- and arc-like molecular features toward the rich and young stellar cluster Westerlund2. The jet has a length of ~100 pc and a width of ~10 pc, while the arc shows a crescent shape with a radius of ~30 pc. These molecular features each have masses of ~10000 solar mass and show spatial correlations with the surrounding lower density HI gas. The jet also shows an intriguing positional alignment with the core of the TeV gamma ray source HESS J1023-575 and with the MeV/GeV gamma-ray source recently reported by the Fermi collaboration. We argue that the jet and arc are caused by an energetic event in Westerlund 2, presumably due to an anisotropic supernova explosion of one of the most massive member stars. While the origin of the TeV and GeV gamma-ray sources is uncertain, one may speculate that they are related to the same event via relativistic particle acceleration by strong shock waves produced at the explosion or by remnant objects such as a pulsar wind nebula or microquasar

    Statistical distribution of binary ligands within rhodium-organic octahedra tunes microporosity in their assemblies

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    Structure-porosity relationships for metal-organic polyhedra (MOPs) are hardly investigated because they tend to be amorphized after activation, which inhibits crystallographic characterization. Here, we show a mixed-ligand strategy to statistically distribute two distinct carbazole-type ligands within rhodium-based octahedral MOPs, leading to systematic tuning of the microporosity in the resulting amorphous solids

    Neuronal Expression of GalNAc Transferase Is Sufficient to Prevent the Age-Related Neurodegenerative Phenotype of Complex Ganglioside-Deficient Mice

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    Gangliosides are widely expressed sialylated glycosphingolipids with multifunctional properties in different cell types and organs. In the nervous system, they are highly enriched in both glial and neuronal membranes. Mice lacking complex gangliosides attributable to targeted ablation of the B4galnt1 gene that encodes β-1,4-N-acetylegalactosaminyltransferase 1 (GalNAc–transferase; GalNAcT−/−) develop normally before exhibiting an age-dependent neurodegenerative phenotype characterized by marked behavioral abnormalities, central and peripheral axonal degeneration, reduced myelin volume, and loss of axo-glial junction integrity. The cell biological substrates underlying this neurodegeneration and the relative contribution of either glial or neuronal gangliosides to the process are unknown. To address this, we generated neuron-specific and glial-specific GalNAcT rescue mice crossed on the global GalNAcT−/− background [GalNAcT−/−-Tg(neuronal) and GalNAcT−/−-Tg(glial)] and analyzed their behavioral, morphological, and electrophysiological phenotype. Complex gangliosides, as assessed by thin-layer chromatography, mass spectrometry, GalNAcT enzyme activity, and anti-ganglioside antibody (AgAb) immunohistology, were restored in both neuronal and glial GalNAcT rescue mice. Behaviorally, GalNAcT−/−-Tg(neuronal) retained a normal “wild-type” (WT) phenotype throughout life, whereas GalNAcT−/−-Tg(glial) resembled GalNAcT−/− mice, exhibiting progressive tremor, weakness, and ataxia with aging. Quantitative electron microscopy demonstrated that GalNAcT−/− and GalNAcT−/−-Tg(glial) nerves had significantly increased rates of axon degeneration and reduced myelin volume, whereas GalNAcT−/−-Tg(neuronal) and WT appeared normal. The increased invasion of the paranode with juxtaparanodal Kv1.1, characteristically seen in GalNAcT−/− and attributed to a breakdown of the axo-glial junction, was normalized in GalNAcT−/−-Tg(neuronal) but remained present in GalNAcT−/−-Tg(glial) mice. These results indicate that neuronal rather than glial gangliosides are critical to the age-related maintenance of nervous system integrity

    Spatiotemporal control of supramolecular polymerization and gelation of metal-organic polyhedra

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    In coordination-based supramolecular materials such as metallogels, simultaneous temporal and spatial control of their assembly remains challenging. Here, we demonstrate that the combination of light with acids as stimuli allows for the spatiotemporal control over the architectures, mechanical properties, and shape of porous soft materials based on metal–organic polyhedra (MOPs). First, we show that the formation of a colloidal gel network from a preformed kinetically trapped MOP solution can be triggered upon addition of trifluoroacetic acid (TFA) and that acid concentration determines the reaction kinetics. As determined by time-resolved dynamic light scattering, UV–vis absorption, and 1H NMR spectroscopies and rheology measurements, the consequences of the increase in acid concentration are (i) an increase in the cross-linking between MOPs; (ii) a growth in the size of the colloidal particles forming the gel network; (iii) an increase in the density of the colloidal network; and (iv) a decrease in the ductility and stiffness of the resulting gel. We then demonstrate that irradiation of a dispersed photoacid generator, pyranine, allows the spatiotemporal control of the gel formation by locally triggering the self-assembly process. Using this methodology, we show that the gel can be patterned into a desired shape. Such precise positioning of the assembled structures, combined with the stable and permanent porosity of MOPs, could allow their integration into devices for applications such as sensing, separation, catalysis, or drug release

    Kawasaki Disease

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    Kawasaki disease is an acute febrile, systemic vasculitic syndrome of an unknown etiology that primarily occurs in children younger than five years of age. The principal presentations of Kawasaki disease include fever, bilateral nonexudative conjunctivitis, erythema of the lips and oral mucosa, changes in the extremities, rash, and cervical lymphadenopathy. Coronary artery aneurysms or ectasia develops in 15% to 25% of untreated children with the disease, which may later lead to myocardial infarction, sudden death, or ischemic heart disease. Treatment with intravenous gamma globulin (IVIG) is effective, but the mode of action is still unclear. The development of a diagnostic test, a more specific therapy, and ultimately the prevention of this potentially fatal illness in children are all dependent upon the continued advances in determining the etiopathogenesis of this fascinating disorder
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