It has been announced that Professor Tomoko Hasegawa (RARA Fellow, Research Organization of Science and Technology) and Professor Hidenori Arai (RARA Fellow, Research Organization of Science and Technology) are both listed on the Highly Cited Researchers 2025 selected by Clarivate Analytics. This marks Prof. Hasegawa’s seventh consecutive year and Prof. Arai’s fifth consecutive year on the list.

　Each researcher on the list has authored multiple Highly Cited Papers that rank in the top 1% by citations in a specific publication year and field(s), and has had a significant impact on subsequent research. This time round, 6,868 researchers active across diverse fields have been selected. Profs. Hasegawa and Arai are in the “Cross-Field Category,” in which researchers are evaluated based on the total number of citations for papers published in multiple fields by a single researcher.

　Prof. Hasegawa researches global environmental issues, particularly climate change, using integrated assessment models—computer simulation models that comprehensively analyze factors such as energy, economics, agriculture, land use, and water use. Specifically, she focuses on projecting future greenhouse gas emissions, examining strategies to reduce them, and conducting economic analyses of the impacts of climate change.

　Prof. Arai, as President of the National Center for Geriatrics and Gerontology, promotes the provision of advanced medical models for geriatric syndromes such as sarcopenia, frailty, and dementia, fosters the development of medical, health, and welfare professionals, and leads research on well-being both domestically and internationally. At the Ritsumeikan Advanced Research Academy (RARA), he is advancing research activities under two major themes: “Industry-government-academia collaborative frailty prevention project using digital technology” and “Development of methods for social inclusion of disabilities prone to stigmas (particularly dementia),” aiming to extend healthy life expectancy for older people.

Comments from Prof. Hasegawa

　I am deeply honored to have been selected for the Highly Cited Researchers 2025 list, following last year’s recognition. This selection, along with previous ones, primarily reflects my work on a series of studies assessing the impacts of climate change and its mitigation on agriculture and land use within the Agricultural Model Intercomparison and Improvement Project (AgMIP), published in 2014, and the development and a series of related researches on the Shared Socioeconomic Pathways (SSPs), published in 2017. Furthermore, I also consider this to be the culmination of climate change-related researches based on the development and application of the Asia-Pacific Integrated Model (AIM), in collaboration with the National Institute for Environmental Studies, Kyoto University, and researchers across Asia, as well as numerous other joint research achievements with many overseas research institutions and researchers.
　I extend my heartfelt gratitude to all my collaborators for their long-standing guidance and cooperation, and to all members of the University for their support day in day out.
　Encouraged by this honor, I intend to continue contributing to the advancement of this research field and to return the research outcomes to society.

Comments from Prof. Arai

　I am deeply honored to have been selected as a Highly Cited Researcher 2025, following last year’s recognition. I extend my heartfelt gratitude to my collaborators, colleagues at my institution, and all those in clinical and care settings who work tirelessly every day to realize healthy longevity for older people.
　I believe this selection stems from the significant citations received for our international, interdisciplinary research activities on sarcopenia and frailty. Notably, the Asia Working Group for Sarcopenia (AWGS) published its findings in 2014, 2016, 2020, 2021, 2022, and 2023, culminating in the publication of a new consensus in Nature Aging in 2025. While the numerous citations of these papers are the primary reason for this award, I am also deeply grateful to my collaborators for the opportunity to engage in extensive research related to improving the well-being of older people, including studies on sarcopenia, frailty, and dementia. Sarcopenia, frailty, and dementia have become critically important themes for both society and healthcare as global aging progresses. Precisely because Japan is facing the “super-aged society” ahead of the world, I believe our research carries an international responsibility and mission. I perceive this award as both recognition of our past achievements and an expectation for further scientific exploration and societal implementation.
　Moving forward, we will continue to promote interdisciplinary approaches integrating basic science, clinical research, public health, and digital health. This includes projects like the industry-government-academia collaboration for extending healthy life expectancy through digital health, and initiatives focused on social inclusion for disabilities prone to stigmas, such as dementia. Through evidence-based intervention and implementation research, we aim to contribute to extending the healthy life expectancy and enhancing the well-being of each and every senior citizen.