Dealloying of Cu–Zr–Ti bulk metallic glass in hydrofluoric acid solution

The dealloying behavior of Cu 60 Zr 30 Ti 10 metallic glass was investigated under free corrosion conditions using hydrofluoric acid (HF) solutions at room temperature. After immersing in HF solutions with various concentrations (0.05, 0.1, 0.5 and 1 M) for 300 s, color of all samples changed to be pinkish or peachy, which was ascribed to Cu based on the XRD patterns. According to the SEM-EDS study, HF immersion selectively leached the Zr and Ti elements, leaving Cu behind. Increasing the HF concentration increased the dealloying rate. Moreover, the HF concentration strongly influenced the surface morphology of the resulting Cu

〈実践報告〉重度・重複障害児の認知学習における授業設計過程の検討

本研究は，重度・重複障害児における認知学習に焦点をあて，3 事例を対象に実態把握から指導内容の設定，評価における一連の授業設計過程を整理し，検証することを目的とした。対象児童の在籍校であるX特別支援学校における個別の指導計画の作成手続きに従い，①児童の実態把握，②中心課題の設定，③指導目標の設定，④指導の実施及び評価の手続きでまとめた。児童の実態把握から中心課題を設定し，それが達成されるためには，どのような要因が背景として考えられるのかを仮定し，指導目標を設定，実践した。こうした一連の手続きによって，目標から適切な学習を導くことができた。現在行っている学習が何につながっているのかを教師が常に意識しながら指導にあたることができ，指導の見通しが持ちづらいといわれる重度・重複障害児に対する，系統性のある指導を実現するための示唆が得られた。一方で，より長期的な視点や実践の積み重ねが必要であると考えられた

Single nucleotide variations in CLCN6 identified in patients with benign partial epilepsies in infancy and/or febrile seizures

Nucleotide alterations in the gene encoding proline-rich transmembrane protein 2 (PRRT2) have been identified in most patients with benign partial epilepsies in infancy (BPEI)/benign familial infantile epilepsy (BFIE). However, not all patients harbor these PRRT2 mutations, indicating the involvement of genes other than PRRT2. In this study, we performed whole exome sequencing analysis for a large family affected with PRRT2-unrelated BPEI. We identified a non-synonymous single nucleotide variation (SNV) in the voltage-sensitive chloride channel 6 gene (CLCN6). A cohort study of 48 BPEI patients without PRRT2 mutations revealed a different CLCN6 SNV in a patient, his sibling and his father who had a history of febrile seizures (FS) but not BPEI. Another study of 48 patients with FS identified an additional SNV in CLCN6. Chloride channels (CLCs) are involved in a multitude of physiologic processes and some members of the CLC family have been linked to inherited diseases. However, a phenotypic correlation has not been confirmed for CLCN6. Although we could not detect significant biological effects linked to the identified CLCN6 SNVs, further studies should investigate potential CLCN6 variants that may underlie the genetic susceptibility to convulsive disorders.Toshiyuki Yamamoto, Keiko Shimojima, Noriko Sangu, Yuta Komoike, Atsushi Ishii, Shinpei Abe, Shintaro Yamashita, Katsumi Imai, Tetsuo Kubota, Tatsuya Fukasawa, Tohru Okanishi, Hideo Enoki, Takuya Tanabe, Akira Saito, Toru Furukawa, Toshiaki Shimizu, Carol J. Milligan, Steven Petrou, Sarah E. Heron, Leanne M. Dibbens, Shinichi Hirose, Akihisa Okumur

Oxygen isotope evidence from Ryugu samples for early water delivery to Earth by CI chondrites

The delivery of water to the inner Solar System, including Earth, is still a debated topic. A preferential role for hydrated asteroids in this process is supported by isotopic measurements. Carbonaceous chondrite (CC) meteorites represent our main source of information about these volatile-rich asteroids. However, the destruction of weaker materials during atmospheric entry creates a bias in our CC data. The return of surface materials from the C-type asteroid 162173 Ryugu by the Hayabusa2 spacecraft provides a unique opportunity to study high-porosity, low-density, primitive materials, unrepresented in the meteorite record. We measured the bulk oxygen isotope composition from four Ryugu particles and show that they most closely resemble the rare CI (CC Ivuna-type) chondrites, but with some differences that we attribute to the terrestrial contamination of the CI meteorites. We suggest that CI-related material is widespread among carbonaceous asteroids and a more important source of Earth’s water and other volatiles than its limited presence in our meteoritic collection indicates