Published papers

SARS-CoV-2 is the causative agent of COVID-19, which is a global pandemic. SARS-CoV-2 is transmitted rapidly via contaminated surfaces and aerosols, emphasizing the importance of environmental disinfection to block the spread of virus. Ultraviolet C radiation and chemical compounds are effective for SARS-CoV-2 disinfection, but can only be applied in the absence of humans due to their toxicities. Therefore, development of disinfectants that can be applied in working spaces without evacuating people is needed. Here we showed that TiO2-mediated photocatalytic reaction inactivates SARS-CoV-2 in a time-dependent manner and decreases its infectivity by 99.9% after 20 min and 120 min of treatment in aerosol and liquid, respectively. The mechanistic effects of TiO2 photocatalyst on SARS-CoV-2 virion included decreased total observed virion count, increased virion size, and reduced particle surface spike structure, as determined by transmission electron microscopy. Damage to viral proteins and genome was further confirmed by western blotting and RT-qPCR, respectively. The multi-antiviral effects of TiO2-mediated photocatalytic reaction implies universal disinfection potential for different infectious agents. Notably, TiO2 has no adverse effects on human health, and therefore, TiO2-induced photocatalytic reaction is suitable for disinfection of SARS-CoV-2 and other emerging infectious disease-causing agents in human habitation.

In this research, we proposed a national integrated agricultural field data API that combines field polygons, agricultural field pins, and soil map data. To improve the convenience of using agricultural field data as the foundation of agricultural production, we organized various data related to agriculture as well as current conditions and problems with the data collaboration platform WAGRI, which is commonly used in agriculture in Japan; we then created an integrated national agricultural field data API. Three types of data were targeted: field polygons, agricultural field pins, and soil maps. We tried to integrate the field pins and soil maps based on field polygons and were able to completely integrate 5,999,291 of the 31,591,036 basic data points, for a success rate of 19.0%. The remaining data could not be integrated because some data were missing and there were format differences, including the existence of multiple integration targets. To solve this problem, the rules for preparing the target agricultural data must be unified. API's output formats are GeoJSON and WebMapTileService (WMTS), which are standard formats in geographic information systems. We confirmed the API was more convenient to use because a user can obtain three data types in one request. To improve widespread use, we still need to speed up data integration and add a mechanism that can download many types of data at once.

In the production of high-grade tree fruits, it is important not only to maximize fruit quality, but also to guarantee the quality so that consumers can buy with confidence. It is also necessary to minimize the increase in labor costs associated with maximizing fruit quality. We propose a quality control system named the tutor model for individual high-grade fruits based on information and communication technology. Previously, we have developed a quality control system named the school model for fruits that can be grown in large quantities at a relatively low price, such as mandarin oranges. The school model uses data measured from sample fruits to represent the whole crop. There was no guarantee that the individual fruits meet the required quality standards, and no mechanism that consumers can buy with confidence. In the tutor model, electronic tags or QR code tags are attached to individual fruits. The producer records individual sugar content measured during culture, corresponding to the tags. The system advises the producer to reduce the difference between the target and measured values of individual fruits. Fruits are shipped with their tags so that consumers can obtain information from the tag and buy with confidence. An experiment conducted with ‘Shine Muscat’ grape showed that the risk of shipping low-sugar-content fruits could be reduced and the increase in labor could be restricted to 4.5%.

Home cares and facility cares are important in Japan because of aging issues in Japan. One of the most important things in a care is Quality of Life (QOL) of patients. However, QOL of caregivers is also important and increasing a turnover by a low level of QOL is becoming an issue in japan. To solve the lack of caregivers, some research indicates the importance of improving QOL of caregivers. However, in most situations, giving better QOL of patients and caregivers is a trade-off. We propose a prototype system for a care matching to optimize QOL of patients and caregivers considering their care categories and relationships of patients and caregivers.

`WAGRI', the agricultural data collaboration platform is unprecedented agricultural platform in Japan. WAGRI is not only characterized by its big data platform, but also its capability to provide with API services without any software development. The latter feature is realized by novel architecture, `Dynamic API', which enables rapid implementation of API services for unforeseen requirements from agricultural fields. This paper elaborates WAGRI, including its services, function and its architecture.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a pandemic threat worldwide and causes severe health and economic burdens. Contaminated environments, such as personal items and room surfaces, are considered to have virus transmission potential. Ultraviolet C (UVC) light has demonstrated germicidal ability and removes environmental contamination. UVC has inactivated SARS-CoV-2; however, the underlying mechanisms are not clear. It was confirmed here that UVC 253.7 nm, with a dose of 500 μW/cm2, completely inactivated SARS-CoV-2 in a time-dependent manner and reduced virus infectivity by 10–4.9-fold within 30 s. Immunoblotting analysis for viral spike and nucleocapsid proteins showed that UVC treatment did not damage viral proteins. The viral particle morphology remained intact even when the virus completely lost infectivity after UVC irradiation, as observed by transmission electronic microscopy. In contrast, UVC irradiation-induced genome damage was identified using the newly developed long reverse-transcription quantitative-polymerase chain reaction (RT-qPCR) assay, but not conventional RT-qPCR. The six developed long RT-PCR assays that covered the full-length viral genome clearly indicated a negative correlation between virus infectivity and UVC irradiation-induced genome damage (R2 ranging from 0.75 to 0.96). Altogether, these results provide evidence that UVC inactivates SARS-CoV-2 through the induction of viral genome damage.

© 2018 IEEE. We propose an Agri-InfoScience platform which addresses the need for skill transfer in response to various food problems associated with global population growth. The platform consists of various tools and methods for collection, analysis and reconstruction of information. The agricultural skill learning support system is the central tool of the platforms. This system serves to address the issues pertaining to the acquisition of 'master craftsmanship.' We conducted an experiment using kiwi pruning operations as an example of a skill that takes a few years to acquire to verify the effectiveness of the learning support system.

Few studies have comprehensively screened for ionic small molecules with high water-solubility in the traditional Japanese mandarin orange Citrus unshiu Marc. Here, we performed metabolomic analysis with capillary electrophoresis-mass spectrometry (CE-MS) to comprehensively identify and accumulate gross quantitative data for water-soluble components in the different varieties of 'Aoshima' and 'Okitsu/Miyagawa Wase', according to grade and processing method. In this analysis, we focused on 151 components and showed the characteristic components related to each different variety and processing method, e.g., Met, Gly, and Asp in var. Wase; ornithine, putrescine, synephrine, and Gln in var. Aoshima; and pyroglutamate, GABA (γ-aminobutyric acid), and malonate in the juice of var. Aoshima. Furthermore, we conducted processing tests and identified components that were affected by squeezing or heating. These data represent basic data for further investigation of the metabolism of C. unshiu Marc. or chemical changes in their components due to external factors such as processing.