His main research interests include healthcare policy, patient safety, and gender equality in science education. His books include Japanese Women in Science and Engineering: History and Policy Change (with Professor Emeritus Kashiko Kodate, Routledge) and Maternity Services and Policy in an International Context: Risk, Citizenship and Welfare Regimes (with Dr Patricia Kennedy, Routledge).
Nao is also a researcher and a visiting lecturer at the Hokkaido University's Public Policy Research Centre, a senior researcher at the Todai Policy Alternatives Research Institute at the University of Tokyo, and affiliated to the Geary Institute for Public Policy at UCD.
Nao led a UCD Seed Funding project 'Designing a multi-disciplinary team training programme for enhancing care quality for older people'. He was also involved in an international project looking into gender equality in science and engineering education.
He was the Project Leader of the Japan Foundation-sponsored "Ireland-Japan Social Science Symposia (IrJaSS): Sharing knowledge, shaping the future of the welfare society in Europe and Japan" (2014-15), which is a joint project between UCD and the University of Tokyo.