The following are three upcoming ESE dissertation defenses taking place this week and next. Detailed announcements are attached. Amanda Lopez PhD Dissertation Defense Machine Learning for Intelligent Bioprocessing of Unicellular Photosynthetic Systems Major Professor: Dr. George Zhou Tuesday April 14, 2026, at 12:00 PM | CIVL G212 Ecological Sciences and Engineering Interdisciplinary Graduate Program School of Sustainable Engineering and Environmental Engineering Abstract: Translating biofuel technologies into commercially viable conditions is bottlenecked by bioreactors that operate as black-box systems. We know the inputs and can measure the outputs, but the intracellular dynamics in between, driving biosynthesis of biofuel-precursors molecules, remain impossible to control. There is a lack of real-time tools capable of monitoring intracellular biochemical dynamics and anticipating metabolic stress before cultures undergo irreversible shifts. Motivated by this gap, I dedicated my Ph.D. to developing an intelligent, non-destructive low-cost PAT system for early-warning detection of intracellular chlorophyll-to-lipid dominance shift in microalgal bioreactors. I wired the optical sensing hardware, configured the bioreactor platforms, programmed the data acquisition architecture, and implemented a continuous real-time processing AI pipeline. Built upon a physics-informed, time-aware machine learning model, this pipeline is grounded in optical dynamics. It uses causal modeling of light-matter interactions and temporally structured signal deviations to infer intracellular lipid droplet formation and chlorophyll dynamics. Despite a total hardware cost of just $270, the platform achieved predictive accuracies >90% when benchmarked against measurements obtained using $60,000 epifluorescence microscopy instrumentation. Importantly, this system functions as an anticipatory stress detector. It identifies metabolic transitions prior to full phenotypic manifestation and enables proactive adjustment of bioprocess conditions to maintain optimal productivity. Laying the foundation for intelligent, self-driving bioreactors. Carly Frank PhD Dissertation Defense Reframing Climate Risk: From Physical Processes to Social Dimensions Major Professor: Dr. Matt Huber Thursday April 16, 2026, at 9:30 AM | HAMP 2201 | Zoom<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpurdue-edu.zoom.us%2Fj%2F99400014757%3Fpwd%3DWUDe2vvlrpey6HPOx7bM7aQzwXAeGt.1&data=05%7C02%7Cese-faculty-list%40ecn.purdue.edu%7C4f10ee7ac73742c8ee2308de99854681%7C4130bd397c53419cb1e58758d6d63f21%7C1%7C0%7C639116995444306485%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=hHuFz1dHNgJWwcagUengRe7Y%2FbyAcEidLFLvrNTgAjU%3D&reserved=0> Ecological Sciences and Engineering Interdisciplinary Graduate Program Department of Earth, Atmospheric, and Planetary Sciences Abstract: Climate risk is commonly understood as the product of hazard, exposure, and vulnerability, yet each of these components is shaped by choices about measurement, indicators, and aggregation. This dissertation argues that what is measured, and by whom, determines what is recognized as climate risk and what remains invisible. Drawing on multiple empirical approaches, this research shows how structural inequalities influence whose scientific knowledge enters the global record, how conventional temperature metrics can obscure widespread warming, and how alternative measures incorporating humidity reveal different patterns of heat risk. It further demonstrates that these dynamics are not confined to a single region but emerge across diverse hydroclimatic settings through interactions between soil moisture and atmospheric processes. Through a case study of community-led air quality monitoring in Superior, Wisconsin, this dissertation shows how residents can produce knowledge that makes otherwise unrecognized environmental exposures visible and actionable within governance systems. In all, this work shows that climate risk is constructed across multiple scales, from physical measurement to institutional practice, shaping not only how risk is understood, but whose knowledge counts. Nathan Shoaf PhD Dissertation Defense Exploring Risk Perceptions and Management of Soil Contaminants Among Indiana Urban Farmers Major Professor: Dr. Zhao Ma Friday April 24, 2026, at 12:00 PM | PFEN 120 Ecological Sciences and Engineering Interdisciplinary Graduate Program Department of Forestry and Natural Resources Abstract: Increased interest in urban agriculture has grown throughout the United States and Indiana to support local food production, food security, and improve the health of community residents. As urban farmers grow crops on former industrial, residential, and vacant land, they encounter soil conditions from decades of land use changes and industrial activity. Soil contamination exposure is often perceived as a threat, particularly heavy metals (e.g., lead and arsenic), with lower concern and awareness of other contaminants (e.g., pesticides and PFAS). Despite the presence of these contaminants on some urban farms and the potential for public health risks, they are often invisible and difficult to detect without laboratory testing. The perceived threat of soil contaminants is influenced by farmer knowledge of testing procedures, interpretation of test results, and management of soils to reduce future exposure pathways. Many farmers grow crops in raised beds and purchase soils and amendments from commercial nurseries hoping these materials provide a safe alternative for crop production relative to their native soils. However, soil testing remains limited, and farmers often rely on local knowledge, visual assessments, and community knowledge to influence their perceptions of contamination. This dissertation explores gap between contamination awareness and protective behavior among Indiana urban farmers by integrating the Psychometric Paradigm, the Health Belief Model, the Theory of Planned Behavior, and the Norm Activation Theory frameworks in a qualitative study and the Protection Motivation Theory framework in a subsequent quantitative study, as well as applying multi-stressor approaches to urban farmer soil contamination management. This research provides insight into how urban farmers perceive, interpret, and respond to complex contamination risks. Amy Ledman She/Her/Hers Lead Graduate Program Specialist Ecological Sciences and Engineering Office of Interdisciplinary Graduate Programs Ernest C. Young Hall, Rm 825 155 S. Grant St. West Lafayette, IN 47907 o: 765-494-5865 f: 765-496-6271 Schedule a meeting: calendly.com/aledman<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcalendly.com%2Faledman&data=05%7C02%7Cese-faculty-list%40ecn.purdue.edu%7C4f10ee7ac73742c8ee2308de99854681%7C4130bd397c53419cb1e58758d6d63f21%7C1%7C0%7C639116995444437345%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=5rTKn8a0BVOpmzoCiMKZfjxp%2B1tBKJuB%2BW1dmHe5O40%3D&reserved=0> [cid:image001.png@01DCCB4C.9B64F4B0]<https://www.purdue.edu/?utm_source=signature&utm_medium=email&utm_campaign=purdue>
