Maria Aparecida Soares Ruas, a newly elected TWAS Fellow (2025) passed away on 30 June 2025, at the age of 77. She was a professor emerita of mathematics at the Institute of Mathematical and Computational Sciences, University of San Paulo (USP), Brazil where she served as a professor (1981–2012).

She obtained her PhD from USP in 1983, and in her career focused on differential geometry and singularity theory.

During her tenure, she served as the head of the Department of Mathematics and deputy director of the institute, was a member of the university council, and vice-chair of the university’s permanent evaluation committee. She also served in the advisory committees of CAPES (Coordination for the Improvement of Higher Education Personnel) and the National Council for Scientific and Technological Development (CNPq).

A founding member of the Brazilian Mathematical Society, she sat on its board of directors. A leading expert in singularity theory, Ruas coordinated international research exchange projects, including Brazil’s most prominent research groups in the field.

Since 1990, her group had organized the internationally reputed workshop on real and complex singularities. Her scientific contributions to singularity theory included advances in the classification of singularities and their applications to geometry. A member of the Brazilian Academy of Sciences since 2008, she has received the Order of Scientific Merit from the Brazilian government. She published more than 80 scientific articles in international journals, and participated in the production of five books. In January 2025, she received the Latin American Prize for Mathematical Leadership from the Institute of Mathematical Sciences of the Americas.