Development and Validation of Role-play Materials in Mathematics Classes: Let's Decide the Price of Pizza

本研究では授業内で生徒にロール（役割）を設定し，そのロールにとって真正な問題を扱う「ロールプレイ教材」の有効性について考察した。具体的には，中学校3年生対象の教材「ピザの値段を決定しよう」を開発し，ワークシートの記述内容やアンケートの分析を行った。その結果，「ロールプレイ教材」は文章題等に比べて生徒に現実感を与えるものであること，数学にとどまらない多様な価値観に基づく議論を行わせやすい教材であることが明らかになった。In this study, we examined the effectiveness of "role-play materials" in which students are assigned roles in the classroom and have to deal with problems that relate to those roles. Specifically, we developed a teaching material, "Let's decide the price of pizza," for third graders in junior high school, and analyzed the contents of worksheets and questionnaires. The study found that "role-play materials" give students a better sense of reality than textbooks and they can easily have discussions based on various values that are not limited to mathematics

Variants of the Game of Nim that have Inequalities as Conditions

In this article the authors are going to present several combinatorial games that are variants of the game of Nim. They are very different from the traditional game of Nim, since the coordinates of positions of the game satisfy inequalities. These games have very interesting mathematical structures. For example, the lists of P-positions of some of these variants are subsets of the list of P-positions of the traditional game of Nim. The authors are sure that they were the first people who treated variants of the game of Nim conditioned by inequalities. Some of these games will produce beautiful 3D graphics (indeed, you will see the Sierpinski gasket when you look from a certain view point). We will also present some new results for the chocolate problem, a problem which was studied in a previous paper and related to Nim. The authors make substantial use of Mathematica in their research of combinatorial games

Image Quality Improvement for Capsule Endoscopy Based on Compressed Sensing with K-SVD Dictionary Learning

Harada Y., Kanemoto D., Inoue T., et al. Image Quality Improvement for Capsule Endoscopy Based on Compressed Sensing with K-SVD Dictionary Learning. IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E105.A, 743 (2022); https://doi.org/10.1587/transfun.2021EAL2033.Reducing the power consumption of capsule endoscopy is essential for its further development. We introduce K-SVD dictionary learning to design a dictionary for sparse coding, and improve reconstruction accuracy of capsule endoscopic images captured using compressed sensing. At a compression ratio of 20%, the proposed method improves image quality by approximately 4.4 dB for the peak signal-to-noise ratio

Bis(1H-imidazole-κN 3){2,2′-[propane-1,2-diylbis(nitrilo­methyl­idyne)]diphenolato-κ4 O,N,N′,O′}iron(III) perchlorate

The title compound, [Fe(C17H16N2O2)(C3H4N2)2]ClO4, consists of monomeric [Fe(salmen)(HIm)2]+ cations {salmen is the 2,2′-[propane-1,2-diylbis(nitrilo­methyl­idyne)]diphen­olate dianion and HIm is 1H-imiazole} and perchlorate anions. In the cation, the Fe3+ ion is octahedrally coordinated by two N atoms and two O atoms from a tetra­dentate salmen anion and two N atoms from two Him mol­ecules. These ligands are coordinated to the iron ion in a direction perpendicular to the [Fe(salmen)]+ coordination plane. The benzene ring planes in the salmen ligands are oriented nearly parallel to one another inter­molecularly [dihedral angle = 6.36 (3)°]. The dihedral angle between the mean planes through the imidazole rings in the cation is 76.9 (2)°. In the crystal, N—H⋯O inter­actions link the mol­ecules into a one-dimensional double chain running along [101] and C—H⋯O inter­actions link the double chains into a two-dimensional network, running parallel to the ac plane

Detection of CpG Methylation in G-Quadruplex Forming Sequences Using G-Quadruplex Ligands

Genomic DNA methylation is involved in many diseases and is expected to be a specific biomarker for even the pre-symptomatic diagnosis of many diseases. Thus, a rapid and inexpensive detection method is required for disease diagnosis. We have previously reported that cytosine methylation in G-quadruplex (G4)-forming oligonucleotides develops different G4 topologies. In this study, we developed a method for detecting CpG methylation in G4-forming oligonucleotides based on the structural differences between methylated and unmethylated G4 DNAs. The differences in G4 topologies due to CpG methylation can be discriminated by G4 ligands. We performed a binding assay between methylated or unmethylated G4 DNAs and G4 ligands. The binding abilities of fluorescent G4 ligands to BCL-2, HRAS1, HRAS2, VEGF G4-forming sequences were examined by fluorescence-based microtiter plate assay. The differences in fluorescence intensities between methylated and unmethylated G4 DNAs were statistically significant. In addition to fluorescence detection, the binding of G4 ligand to DNA was detected by chemiluminescence. A significant difference was also detected in chemiluminescence intensity between methylated and unmethylated DNA. This is the first study on the detection of CpG methylation in G4 structures, focusing on structural changes using G4 ligands

Kinematic Structure of Molecular Gas around High-mass Star YSO, Papillon Nebula, in N159 East in the Large Magellanic Cloud

We present the ALMA Band 3 and Band 6 results of 12CO(2-1), 13$CO(2-1), H30alpha recombination line, free-free emission around 98 GHz, and the dust thermal emission around 230 GHz toward the N159 East Giant Molecular Cloud (N159E) in the Large Magellanic Cloud (LMC). LMC is the nearest active high-mass star forming face-on galaxy at a distance of 50 kpc and is the best target for studing high-mass star formation. ALMA observations show that N159E is the complex of filamentary clouds with the width and length of ~1 pc and 5 pc - 10 pc, respectively. The total molecular mass is 0.92 x 10^5 Msun from the 13CO(2-1) intensity. N159E harbors the well-known Papillon Nebula, a compact high-excitation HII region. We found that a YSO associated with the Papillon Nebula has the mass of 35 Msun and is located at the intersection of three filamentary clouds. It indicates that the formation of the high-mass YSO was induced by the collision of filamentary clouds. Fukui et al. 2015 reported a similar kinematic structure toward a YSO in the N159 West region which is another YSO that has the mass larger than 35 Msun in these two regions. This suggests that the collision of filamentary clouds is a primary mechanism of high-mass star formation. We found a small molecular hole around the YSO in Papillon Nebula with sub-pc scale. It is filled by free-free and H30alpha emission. Temperature of the molecular gas around the hole reaches ~ 80 K. It indicates that this YSO has just started the distruction of parental molecular cloud.Comment: 28 pages, 7 figures. Submitted to Ap

High-mass star formation triggered by collision between CO filaments in N159 West in the Large Magellanic Cloud

We have carried out 13CO(J=2-1) observations of the active star-forming region N159 West in the LMC with ALMA. We have found that the CO distribution at a sub-pc scale is highly elongated with a small width. These elongated clouds called "filaments" show straight or curved distributions with a typical width of 0.5-1.0pc and a length of 5-10pc. All the known infrared YSOs are located toward the filaments. We have found broad CO wings of two molecular outflows toward young high-mass stars in N159W-N and N159W-S, whose dynamical timescale is ~10^4 yrs. This is the first discovery of protostellar outflow in external galaxies. For N159W-S which is located toward an intersection of two filaments we set up a hypothesis that the two filaments collided with each other ~10^5 yrs ago and triggered formation of the high-mass star having ~37 Mo. The colliding clouds show significant enhancement in linewidth in the intersection, suggesting excitation of turbulence in the shocked interface layer between them as is consistent with the magneto-hydro-dynamical numerical simulations (Inoue & Fukui 2013). This turbulence increases the mass accretion rate to ~6x10^-4 Mo yr^-1, which is required to overcome the stellar feedback to form the high-mass star.Comment: 20 pages, 3 figures, accepted for publication in ApJ