There are a lot of study about effects of light environment on sleep because light has non-visual physiological arousal effects. However, psychophysiological effects of dusk simulated light environment on the succeeding sleep is not yet clear. Accordingly, the purpose of this study was to investigate that the effects of dusk simulated light, in which both amount and correlated color temperature of the LED light is regulated to become gradually lower, on the psychophysiological state of the succeeding sleep. Light conditions were five; one was incandescent lamp with constant light amount (IL), and the other four were dusk simulated polychromatic neutral white and bulb color combined LEDs, of which excitation light is violet (P-) or blue (B-), with two patterns of light control (Twilight or Acute). Participants were 17 young male adults without problems of sleep, and slept for seven hours after light exposure, with one light condition per night, for about 110 minutes. As for the sleep architecture such as sleep stage ratio and sleep latency, there were no significant differences between the five light conditions. However, the relationship between the increasing rate of EEG-delta power component during first 20-minutes and the sleep stage transition time from sleep onset showed significant negative correlation except for blue excitation LEDs conditions. Therefore, it was suggested that the sleep onset process is more natural under the condition of incandescent lamp and of violet excitation LEDs than under the condition of blue excitation LEDs. In addition, the results under the dusk simulated LEDs were compared with those under the constant light amount LEDs used in our previous study, and we considered which is more suitable for light environment before nocturnal sleep. As a result, some of the scores of subjective sleep feelings at the time of waking up were significantly higher in the dusk simulated LEDs condition. Furthermore, the correlation during sleep onset tended to be similar in previous studies. From the above results, it was suggested that the dusk simulated LEDs condition is more suitable as the nocturnal light environment before sleep than the LEDs lighting under the steady condition, and in particular, the violet excitation LEDs may have a psychophysiological affinity.

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Since early dawn on July 4, 2020, the southern Kumamoto prefecture has experienced extremely heavy rainfall. It rained for 24 hours, from noon on July 3 to noon the following day. Cumulative rainfall has surpassed 400mm and was observed in the elliptical ground area of 70km east-west and 30km north-south. The highest 24-hour rain measurement of Amedasu in Hitoyoshi-city was 410.0mm and this surpassed the historical record with a Return Period of 200-400 years. Due to this extremely heavy rainfall, the water level measurement at Hitoyoshi Water Level Observatory exceeded 4.07mm by around 5:30 and after measuring 4.90mm, further measurement was not possible. As a result, both Tamagawa River banks near the city area of Hitoyoshi experienced severe flood disasters caused by overflow and/or damage of the banks. The incident was more than the anticipated level in inundation hazardous areas. Inundation height of the flood was 1.5-3.6m higher than in past recent three floods (Showa 40/46/57). In particular, the shops, Country Inn, and hotels of “Ohina Dori Kokonokamachi” have experienced an inundation height of over 4m and the operation has been suspended or closed down as a result of this flood. Additionally, the terrace surface and natural banks of a slightly elevated area are normally less vulnerable to flood, however, they were also damaged and the inundation height of the hot spring facilities of Nakagamicho in low-lying areas of the flood plain was as high as 620cm. From the analysis of old map data from 1901-1902 to 2009 and aerial photographs, historical changes of land utilization showed that rice fields in low-lying areas were developed for different purposes starting from the 1960s. This is especially true in the mid-area, as it became evident that roadside shops and residential areas were constructed in conjunction with the opening of the national 219 bypass road, and this development of areas with high flood risk has increased the magnitude of the flood damage.

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This study experimentally investigated subjective time from a time perception perspective. Previous experimental psychology studies have indicated the roles of the interstimulus interval, the time error, and the preceding stimulus series in regulating time perception. This study focused on the preceding stimulus series and measured changes in the subjective time of a tone by maintaining the stimuli domain of a series and biasing the stimulus distribution. The results indicated that the measured values were a function of the preceding stimulus duration indicative of perceptual contrast. Moreover, the measured values of an identical stimulus changed according to the series’ stimulus distribution. These tendencies could be anchoring effects caused by preceding stimuli and their distribution. These findings suggest that the subjective time of a specific stimulus changes according to the temporal characteristics of simultaneously presented other stimuli when judging a stimulus. Furthermore, observers’ introspective reports indicated identical results, suggesting the usefulness of observers’ descriptions in examining time perception.

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In our study, we analyzed changes in flood risk caused by transitions in land use in the Aikawa district of Kurume in Japan’s Fukuoka Prefecture, which suffered inundation damage in a heavy rainfall in July 2018, using old editions of maps, residential maps, city planning maps, a landform classification map for flood control, and a map of the predicted flood inundation area. The torrential rains caused inland waters in the Shimoyuge River and Egawa River watersheds, both branches of the Chikugo River, to rise. However, the Egawa River basin, in an urbanization control area, was almost completely undeveloped and suffered no residential flooding. By contrast, the urbanization of low-lying areas in the Shimoyuge River basin in the urbanization promotion area experienced increased damage from flooding. In particular, the Aikawa district in the Shimoyuge River basin became a logistics hub with the establishment of the transportation industry following the opening of the Kyushu Expressway and the Kurume Interchange. Moreover, with the opening of the Aikawa Bypass, roadside stores have opened along the bypass, and housing has been built around them, which has promoted overall development. Although urbanization has progressed, the area is located on a flood plain that is vulnerable to inundation, and the development of low-lying land through conversion to farmland has resulted in increased inundation damage. During the half-century between 1970 and 2020, the building area continued to increase, with a higher percentage of the area in the deeper depths of the flood inundation projection area. It is clear that the increased building area was constructed on land at high risk of flooding.

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This study aims to review previous studies on time cognition of people who appear to have sensory worlds that differ from those of healthy individuals, and to examine their pathologies, abnormal experiences, and distortion of time cognition. Our results confirm that people with mental illnesses, developmental disorders, brain dysfunction, and other ailments can develop diverse impairments of time cognition. The results of our review also suggest impairment of time cognition to be a core symptom of psychopathology; and that, in the practice of clinical psychology, identifying abnormal time cognition in people who come for consultation may help to improve our understanding of their psychopathology and suggest ways of sharing their subjective world.

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The conditions of human life depend on climate, diet, and disease. The presence of microbes, including viruses, fungi, bacteria, Rickettsia spp., parasites, and pathogens, has been associated with many infectious diseases. In this clinical study, we focus on the following infectious diseases: coronavirus disease 2019 (COVID-19), which has been spreading globally since early 2020; and tick-borne disease, including severe fever with thrombocytopenia syndrome (SFTS), which is caused by the SFTS virus, and Japanese spotted fever, which is caused by Rickettsia japonica transmitted from infected ticks, and allergic reactions to galactose-1,3-galactose antigen, which is secreted by noninfected ticks. We also introduce the Oz virus, a novel tick-borne thogotovirus recently discovered in Japan. The findings of the present study indicate that COVID-19 outcomes gave rise to major social questions pertaining to the management of family members and sporadic patients infected with viral disease, and that distributions of infected and/or noninfected ticks will gradually spread across Japan because of climate change exacerbated by environmental stimuli such as CO2 and methane emissions. Taken together with these observations, our findings emphasize that the stabilized coexistence of rational human activities and environmental protections is crucial to achieve a sustainable and constructive future for humanity.

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