Structural Features of Layered Iron Pnictide Oxides (Fe2As2)(Sr4M2O6)

Structural features of newly found perovskite-based iron pnictide oxide system have been systematically studied. Compared to REFePnO system, perovskite-based system tend to have lower Pn-Fe-Pn angle and higher pnictogen height owing to low electronegativity of alkaline earth metal and small repulsive force between pnictogen and oxygen atoms. As-Fe-As angles of (Fe2As2)(Sr4Cr2O6), (Fe2As2)(Sr4V2O6) and (Fe2Pn2)(Sr4MgTiO6) are close to ideal tetrahedron and those pnictogen heights of about 1.40 A are close to NdFeAsO with optimized carrier concentration. These structural features of this system may leads to realization of high Tc superconductivity.Comment: 3pages, 2figures, 1table, proceedings of M2S 200

Introducing E-learning to Lower Level Learners of English: A Preliminary Study

本稿は大学の授業における下位英語学習者へのe-learning 教材導入の有効性及びその効 果的活用方法を検証し考察するものである。E-learning導入後のTOEICスコア変化と自律 学習アンケート結果を、統制群を用いて比較検証した。その結果、distance learning モデ ルである実験群では、TOEIC スコアに大きな伸びがみられたが、GTEC テストを用いた統 制群では、実験群のような著しい伸びは認められなかった。また、実験群では自律学習の アンケート結果から「意識要因」のMotivation とIdeal-Self の値が微増していることが分 かった。本研究は学内COE 教育支援経費を受けての予備調査であるものの、教員の適切な 指導と助言があれば、下位英語学習者へのdistance learning モデルにおいて効果的に e-learning教材が活用出来ることを示唆している

New technologies in rhinoplasty : a comprehensive workflow for computer-assisted planning and execution

Rhinoplasty in facial cleft patients is among the most challenging types of reconstructive facial surgery due to its variability Advances in 3-dimensional imaging enable improved preoperative assessment in rhinoplasty. In complex cases with bony support irregularities and asymmetry, it is rational to initiate planning with reconstruction of the aberrant substructure (ie, "bottom-up" planning) rather than starting the surgical design with soft-tissue morphing. We present a new comprehensive workflow in which novel advanced technologies are implemented to perform "bottom-up" computer-assisted planning and execution in complex rhinoplasty cases. This workflow enables meticulous planning, use of grafting templates, and 3-dimensional-guided osteotomies with integration of piezotome and intraoperative navigation. Previous reports separately discuss some of these innovations. However, greater benefit lies in the combination of these techniques, with emphasis on preoperative computer analysis, virtual planning, and transfer to the operation theater. Surgeons are seeking new ways to enhance minimally invasive approaches and to obtain predictable and favorable clinical results. The presently introduced workflow allows clinicians to plan complex cases in a simple, effective, and safe manner, with the combination of different techniques to produce consistent results

Superconductivity at 38 K in Iron-Based Compound with Platinum-Arsenide Layers Ca10(Pt4As8)(Fe2-xPtxAs2)5

We report superconductivity in novel iron-based compounds Ca10(PtnAs8)(Fe2-xPtxAs2)5 with n = 3 and 4. Both compounds crystallize in triclinic structures (space group P-1), in which Fe2As2 layers alternate with PtnAs8 spacer layers. Superconductivity with a transition temperature of 38 K is observed in the n = 4 compound with a Pt content of x ~ 0.36 in the Fe2As2 layers. The compound with n = 3 exhibits superconductivity at 13 K.Comment: OPEN SELECT article, 11 pages, 5 figures, 2 table

Pressure Dependence of Superconducting Transition Temperature on Perovskite-Type Fe-Based Superconductors and NMR Study of Sr2VFeAsO3

We report the pressure dependences of the superconducting transition temperature (T_c) in several perovskite-type Fe-based superconductors through the resistivity measurements up to ~4 GPa. In Ca_4(Mg,Ti)_3Fe_2As_2O_y with the highest T_c of 47 K in the present study, the T_c keeps almost constant up to ~1 GPa, and starts to decrease above it. From the comparison among several systems, we obtained a tendency that low T_c with the longer a-axis length at ambient pressure increases under pressure, but high T_c with the shorter a-axis length at ambient pressure hardly increases. We also report the ^75As-NMR results on Sr_2VFeAsO_3. NMR spectrum suggests that the magnetic ordering occurs at low temperatures accompanied by some inhomogeneity. In the superconducting state, we confirmed the anomaly by the occurrence of superconductivity in the nuclear spin lattice relaxation rate 1/T_1, but the spin fluctuations unrelated with the superconductivity are dominant. It is conjectured that the localized V-3d moments are magnetically ordered and their electrons do not contribute largely to the Fermi surface and the superconductivity in Sr_2VFeAsO_3.Comment: 7 pages, 9 figure