Allowed slepton intergenerational mixing in light of light element abundances

We studied allowed region on the intergenerational mixing parameters of sleptons from a viewpoint of big-bang nucleosynthesis in a slepton-neutralino coannihilation scenario. In this scenario, $^7$Li and $^6$Li problems can be solved by considering exotic reactions caused by bound-state effects with a long-lived slepton. Light element abundances are calculated as functions of the relic density and lifetime of the slepton which considerably depend on the intergenerational mixing parameters. Compared with observational light element abundances, we obtain allowed regions on the intergenerational mixing. Ratio of selectron component to stau component, $c_e$, is allowed in $2\times 10^{-11} \lesssim c_e \lesssim 2\times 10^{-9}$ with solving both the $^7$Li and $^6$Li problems. Similarly, the ratio for smuon, $c_{\mu}$, is allowed in $10^{-7} \lesssim c_{\mu} \lesssim 5\times 10^{-5}$ for mass difference between slepton and neutralino, which is smaller than muon mass, and $$ for the mass difference in range between muon mass and 125 MeV. We also discuss collider signatures of the slepton decays. We find characteristic double peaks in momentum distribution of event number of the slepton decays with allowed mixing parameters. Discoveries of the double peaks at future collider experiments should confirm our scenario.Comment: 10 pages, 6 figure

高等学校理科における批判的思考力の育成に関する研究

内容の要約広島大学(Hiroshima University)博士(教育学)Doctor of Philosophy in Educationdoctora

Research on information propagation analyzing odds in horse racing

We focus on the odds in horse racing to study the information propagation to get an idea for fluctuation on information propagation. Analyzing past data of horse racing, and constructing a mathematical model of winning probability, we find a correlation between odds and results of races. As a first step, we focus on two ways of betting called „WIN” and „EXACTA.” We confirm that the winning probability derived from odds of each horse is mostly in accord with actual data. Then, comparing the result with a stochastic model of winning probability constructed with EXACTA odds, we find out fluctuations between them. Finally, we consider where is the origin of the fluctuations

Study on Critical Thinking of South Korean High School Students in Science Learning

This study intended to clarify the realities of critical thinking of South Korean high school students in science learning. A 42-question survey was conducted on 156 1st-year South Korean high school students to achieve this end. The results indicated that, as well as having a strong curiosity about phenomena, students collect as much experimental data as possible, carefully ascertain cause and thoroughly examine and interpret results. The results also showed that students tend to focus on the collection of experimental data and its interpretation more so than the validity and reproducibility of the experiment and that there is an issue in that they lack a healthy skepticism for things. In addition, the causal relationship of “the deeper a student thinks about things and the more they ascertain the significance and essence, the more carefully they collect experimental data and examine its interpretation” was also clarified as a factor structure that influences the critical thinking of students. At the same time, the causal relationship of “the more inquisitive the student, the more they think about things with a healthy skepticism and without blindly accepting external information, focus on the validity and reproducibility of the experiment and reflect on their own ideas and actions” was also clarified

Added Diagnostic Value of Cerebrospinal Fluid Carcinoembryonic Antigen in a Patient with Leptomeningeal Carcinomatosis as the Initial Manifestation of Gastric Cancer

A 77-year-old woman with no history of malignancy presented with anorexia and bilateral lower extremity weakness. Her consciousness level worsened daily, so we performed a lumbar puncture. Cerebrospinal fluid (CSF) analysis indicated meningitis, but three rounds of CSF cytology showed no malignant cells. The patient’s carcinoembryonic antigen (CEA) level was highly elevated in CSF, but normal in serum. Through gadolinium-enhanced brain/spinal magnetic resonance imaging and gastrointestinal endoscopy, she was diagnosed with leptomeningeal carcinomatosis (LC) from gastric cancer. CEA level in CSF facilitated the diagnosis of LC from gastric cancer because there were no malignant cells on CSF cytology