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Yizhuo Zhang

Presidential Fellow

Yizhuo Zhang is a PhD student in the , advised by , , and Dr. Carrie McDonough. He graduated with a bachelor's degree in Water Science and Engineering in 2022, from Chongqing University in China, and obtained his mater's degree in Civil and Environmental Engineering from Cornell University in 2024. His current research is to evaluate the long-term distribution of PFAS in agricultural systems, including the mass that remains in soil, moves into the food web, or migrates below the root zone to understand exposure risks and design interventions to mitigate those risks.

Dennis Doyle (they/them)

Dennis Doyle is a PhD student in the Department of Chemistry and a member of the . They are advised by Dr. Ryan Sullivan. Dennis received a BS in Chemistry and BA in Studio Arts from the University of Pittsburgh in 2019 and a Masters in Fine Arts in Sculpture and Post Studio Practice from the University of Colorado at Boulder in 2023. Their doctoral research focuses on understanding the physical underpinnings of micro droplet accelerated chemistry using aerosol optical tweezers and Raman spectroscopy. They are interested how this phenomenon applies to aerosol chemistry in the atmosphere and as well as its potential for environmental contaminant remediation.

Laura McDonnell

Laura McDonnell is a PhD student in the at Â鶹´å. In 2024, Laura received her bachelor’s degree in Biochemistry from Temple University in Philadelphia. Her research focuses on developing computational methods to identify and engineer enzymes capable of degrading per- and polyfluoroalkyl substances (PFAS), a class of persistent environmental pollutants commonly known as “forever chemicals.” Currently, she is working on curating comprehensive enzyme datasets, generating sequence similarity networks, and applying machine learning techniques to predict and design dehalogenase enzymes with enhanced PFAS degradation capabilities. Her work aims to advance bioremediation strategies and provide novel tools to address the global challenge of PFAS contamination.

Malena Rybacki (they/them/theirs)

Malena obtained their Bachelor's degree in Chemical Engineering from University of Pittsburgh in 2023. Upon joining in January 2025, Malena began research into atmospheric chemistry with . Here, their work focuses on developing novel gas measurement techniques that significantly reduce constraints posed by traditional measurement methods. Having been raised in Pittsburgh, Malena is deeply connected to the city and aims to engage the local community in atmospheric health through their research.