仲矢 史雄

In Japan, there are many disasters such as earthquakes and typhoons; thus, the acquisition of knowledge and skills related to disaster preparation by the public is a key issue. In disaster preparation education, learning should be sustained until the disaster situation, not immediately after learning. In this study, we examined the effects of disaster education events on learning disaster preparation knowledge among elementary school children. We conducted two tests—a post-test and a post-post-test—immediately after the disaster education event in 2019 and six months after the event, respectively. These scores were used to measure persistence of learning. We confirmed that the improvement of knowledge and skills related to disaster reduction was sustained even after a certain period had passed since the disaster preparation education.

In this paper, we propose a teacher training system that incorporates educational digital portfolios using the Social Networking Service (SNS). We considered the situation in which the student teaching period occurs and focused on the educational benefits of using the SNS to communicate remotely. A challenging issue during the teacher training practicum is ensuring efficient communication and consistent evaluation between the university professor, host school mentor and university student. Our proposed system promotes the development of effective teaching and evaluation methods by sharing knowledge and practice records concerning the teaching practicum.

In the late 1990s, the once prolific populations of the coral Acropora intermedia surrounding Okinawa, Japan, dramatically declined because of thermal stress, bleaching caused by heat stress, and consequent mortality. Before the bleaching event, 72 fragments (about 15 cm in length) were collected and transferred to the Okinawa Churami Aquarium. Through growth and repeated fragmentation, these original fragments developed into about 100 colonies that spawned from 1999 to 2009. In this study, we compared gametogenesis, fertilization, survival, and O2 consumption in cultured and wild colonies of A. intermedia and their offspring. Cultured A. intermedia had larger oocytes and higher fertilization and survival rates than samples from wild colonies. O2 consumption of cultured embryos was similar to that of wild embryos. These results suggest that cultured A. intermedia and their offspring are as viable as wild colonies. Aquaria can play a role in the conservation of endangered corals, and their cultured colonies could be used to re-establish devastated species on the Okinawa reefs.

In order to characterize the energy expenditure of Paramecium, we simultaneously measured the oxygen consumption rate, using an optic fluorescence oxygen sensor, and the swimming speed, which was evaluated by the optical slice method. The standard metabolic rate (SMR, the rate of energy consumption exclusively for physiological activities other than locomotion) was estimated to be 1.18×10-6Jh-1 cell-1 by extrapolating the oxygen consumption rate into one at zero swimming speed. It was about 30% of the total energy consumed by the cell swimming at a mean speed of 1 mms -1, indicating that a large amount of the metabolic energy (about 70% of the total) is consumed for propulsive activity only. The mechanical power liberated to the environment by swimming Paramecium was calculated on the basis of Stokes' law. This power, termed Stokes power, was 2.2×10 -9Jh-1 cell-1, indicating extremely low efficiency (0.078%) in the conversion of metabolic power to propulsion. Analysis of the cost of transport (COT, the energy expenditure for translocation per units of mass and distance) revealed that the efficiency of energy expenditure in swimming increases with speed rather than having an optimum value within a wide range of forced swimming, as is generally found in fish swimming. These characteristics of energy expenditure would be unique to microorganisms, including Paramecium, living in a viscous environment where large dissipation of the kinetic energy is inevitable due to the interaction with the surrounding water.