Gauss maps of cuspidal edges in hyperbolic 3-space, with application to flat fronts

We study singularities of de Sitter Gauss map images of cuspidal edges in hyperbolic 3-space. We show relations between singularities of de Sitter Gauss map images and differential geometric properties of cuspidal edges. Moreover, we apply this result to flat fronts in hyperbolic 3-space

A novel symmetry in nanocarbons: pre-constant discrete principal curvature structure

Since the first-principles calculations in quantum chemistry precisely provide possible configurations of carbon atoms in nanocarbons, we have analyzed the geometrical structure of the possible carbon configurations and found that there exists a novel symmetry in the nanocarbons, i.e., the pre-constant discrete principal curvature (pCDPC) structure. In terms of the discrete principal curvature based on the discrete geometry for trivalent oriented graphs developed by Kotani, Naito, and Omori (Comput. Aided Geom. Design, $\bf{58}$, (2017), 24-54), we numerically investigated discrete principal curvature distribution of the nanocarbons, C$_{60}$, carbon nanotubes, C$_{120}$ (C$_{60}$ dimer), and C$_{60}$-polymers (peanut-shaped fullerene polymers). While the C$_{60}$ and nanotubes have the constant discrete principal curvature (CDPC) as we expected, it is interesting to note that the C$_{60}$-polymers and C$_{60}$ dimer also have the almost constant discrete principal curvature, i.e., pCDPC, which is surprising. A nontrivial pCDPC structure with revolutionary symmetry is available due to discreteness, though it has been overlooked in geometry. In discrete geometry, there appears a center axisoid which is the discrete analogue of the center axis in the continuum differential geometry but has three-dimensional structure rather than a one-dimensional curve due to its discrete nature. We demonstrated that such pCDPC structure exists in nature, namely in the C$_{60}$-polymers. Furthermore, since we found that there is a positive correlation between the degree of the CDPC structure and stability of the configurations for certain class of the C$_{60}$-polymers, we also revealed the origin of the pCDPC structure from an aspect of materials science.Comment: 18 page

A Practice of “Fushizukuri Education”: Focusing on Rhythm Learning at Hiroshima Municipal Hesaka Elementary School

“Fushizukuri Education” is the most successful music education method in Japan, started in 1966 at Furukawa Elementary School in Hida area, Gifu Prefecture. This method was developed by a group of teachers who were not specialized in music. The characteristics of this method are as follows: (1) the curriculum consists of 30 phases, 102 steps; (2) adopting dual approach comprised of performance and music basics; (3) the learners themselves progress the class with minimum intervention by the teacher; (4) special emphasize is placed on hearing; (5) sufficient opportunities for solo singings and remarks are guaranteed for all learners, (6) the teacher’s remarks are minimized, and (7) the learners eventually demonstrate excellent musical and performance ability. This study aims to find how to install “Fushizukuri Education” effectively into current school music curricula in Japan. Both practical and experimental approaches are employed. Children participated in this study were the third graders at Hesaka Elementary School. The four classes were randomly divided into two groups comprised of two classes each. Children in one group learned using conventional staff notation system, whereas children in the other group learned using the “maru-fu” (circle notes) notation system. Rhythm learning activities were organized for both groups based on the “Fushizukuri Education” method. A pretest and a posttest were carried out in July and late September 2017, respectively. Both tests measured each child’s abilities of rhythm reproduction and rhythm reading. In the rhythm reading pretest, both groups were tested with one-line staff materials. In the rhythm reading posttest, the “maru-fu” group was tested with “maru-fu” materials, whereas the staff group was tested with one-line staff materials. Following results were obtained. (1) Both groups have developed abilities of rhythm reproduction and rhythm reading through rhythm learning activities, although the number of activities was not so many. (2) In the pretest, the staff group outperformed the “maru-fu” group on both reproduction task and reading task. (3) It is presumed that the learners have been familiarized with five-line or one-line staff notation system up to the third grade, whereas they might feel novelty in the “maru-fu” notation system. (4) Therefore, the “maru-fu” notation system should be used in the first grade.三村真弓教授退職記念号 Special Number Commemorating the Retirement of Professor Mayumi Mimur

Algorithmic group formation and group work evaluation in a learning analytics-enhanced environment: implementation study in a Japanese junior high school

In-class group work activities are found to promote the interpersonal skills of learners. To support the teachers in facilitating such activities, we designed a learning analytics-enhanced technology framework, Group Learning Orchestration Based on Evidence (GLOBE) using data-driven approaches. In this study, we implemented the algorithmic group formation and group work evaluation systems in a Japanese junior high school context. Data from a series of 12 collaborative learning activities were used to validate the difference in the measured heterogeneity of the formed homogeneous and heterogeneous groups compared to random grouping. Further, the peer rating and self-perception of the group work were compared for comparative reading and idea exchange tasks. We found algorithmically formed groups, considering the learner model data, either heterogeneously or homogeneously performed better than random grouping. Specifically, students in groups created by the homogeneous algorithm received higher peer ratings and more positive self-perception of group work in the idea exchange group tasks. We did not find significant differences in the comparative reading tasks. Along with the empirical findings, this work presents a paradigm of continuous data-driven group learning support by incorporating the peer and teacher evaluation scores as an input to the subsequent algorithmic grouping

Direction of collaborative problem solving-based STEM learning by learning analytics approach.

The purpose of this study was to explore the factors that might affect learning performance and collaborative problem solving (CPS) awareness in science, technology, engineering, and mathematics (STEM) education. We collected and analyzed data on important factors in STEM education, including learning strategy and learning behaviors, and examined their interrelationships with learning performance and CPS awareness, respectively. Multiple data sources, including learning tests, questionnaire feedback, and learning logs, were collected and examined following a learning analytics approach. Significant positive correlations were found for the learning behavior of using markers with learning performance and CPS awareness in group discussion, while significant negative correlations were found for some factors of STEM learning strategy and learning behaviors in pre-learning with some factors of CPS awareness. The results imply the importance of an efficient approach to using learning strategies and functional tools in STEM education

Modified Bentall operation with bioprosthetic valve and Valsalva graft conduit:the "slit skirt" technique

We elucidated the efficacy of the slit skirt technique to prevent bleeding from the proximal anastomosis between the graft and aortic annulus. Between September 2008 and September 2014, 15 patients underwent a modified Bentall operation with the slit skirt technique at our institution. No patients had bleeding from the proximal anastomosis. No re-thoracotomy for bleeding was required. During midterm follow-up (median period, 21 months), no patient had pseudoaneurysms at the proximal suture line. We conclude that the slit skirt technique is useful to prevent bleeding from the proximal anastomosis after the Bentall operation

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target