著者

Noriko Shimasaki Hideaki Morikawa

出版者

Fuji Technology Press Ltd.

雑誌

Journal of Disaster Research (ISSN:18812473)

巻号頁・発行日

vol.16, no.1, pp.61-69, 2021-01-30 (Released:2021-01-30)

参考文献数

49

被引用文献数

4

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A new infectious disease caused by a novel coronavirus (COVID-19) has spread rapidly worldwide in 2020. The COVID-19 pandemic in Japan can be viewed as an urban disaster because transmission of this respiratory disease tends to occur in densely populated areas. A scientific understanding of the pathogen itself, the cause of the disaster (infectious disease), as well as infection control measures, are important to implement robust and appropriate countermeasures. This review discribes the features, especially the modes of transmission, of COVID-19 and the principles by which infection control is possible using one of the most effective infection control measures – personal protective equipment (PPE). Because COVID-19 is often transmitted to others by asymptomatic individuals through droplets, even those who are unaware of their infection should wear masks to prevent the spread of droplets that may contain the virus and effectively control the spread of disease. However, given the worldwide competition for masks and the urgent requirement of effective controls, it is necessary to conduct further research to establish a system that can supply adequate numbers of masks to regions where many people are infected in the country, with no shortage of masks, in order to make the country more resilient to disasters caused by infectious diseases in the future.

著者

Yujun Wang Mikihiko Miura Hideaki Morikawa

出版者

(社)日本蚕糸学会

雑誌

Journal of Insect Biotechnology and Sericology (ISSN:13468073)

巻号頁・発行日

vol.72, no.1, pp.71-77, 2003 (Released:2004-10-27)

参考文献数

6

被引用文献数

1

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In a few genetic strains of the silkworm, Bombyx mori, two mature larvae jointly spin a large cocoon called a double cocoon with a high frequency. We measured the behaviour of the silkworm to spin double cocoons and analysed the data to examine the relationships between the two silkworms concerning the sharing of the cocoon construction, the relative positions of the two silkworms, the moving properties and the spinning speed. As a result, we were able to visually show the spinning positions and the sharing of the two silkworms for the construction of the cocoon. The results showed that they fixed their bodies in the same or opposite direction with a high frequency. Furthermore, in one race of double cocoons, pseudo-periodicity existed in the serial change of the angle between the two silkworm bodies. There was a difference between the transition probabilities of the two different kinds of double cocoons. The behaviour of one silkworm affected the movement of the other silkworm in one of the double cocoons, though the two silkworms behaved more independently in the other double cocoon. They moved the spinneret significantly faster when the hind parts of the body were being fixed than when they were moving, although there was no definite difference between the spinning speed of the two silkworms.