Curtis L. Johnson, PhD
Principal Investigator
Associate Professor,
Department of Biomedical Engineering
Dr. Johnson directs the Mechanical Neuroimaging Lab in the Department of Biomedical Engineering at UD. He graduated with his BS in Mechanical Engineering from Georgia Tech in 2007, and got his PhD in Mechanical Engineering from the University of Illinois at Urbana-Champaign in 2013. His awards include:
Junior Fellow, International Society for Magnetic Resonance in Medicine
Young Investigator Award, IEEE EMBS BRAIN Grand Challenges conference
Research Summit Award, Delaware INBRE Program
Early Career Researcher Award, Journal of the Mechanical Behavior of Biomedical Materials
Bernard Canavan Early Career Faculty Research Award, Department of Biomedical Engineering, University of Delaware
Outstanding Early Career Faculty Award, College of Engineering, University of Delaware
Gerard J. Mangone Young Scholar Award, Francis Alison Society, University of Delaware
Dr. Johnson is an affiliated faculty member in Mechanical Engineering, Electrical and Computer Engineering, Psychological and Brain Sciences, and Biomechanics and Movement Sciences Program at UD. He is also affiliated faculty in Biomedical Research at Nemours/A.I. duPont Hospital for Children.
Staff
Katrina is a joint Postdoctoral Researcher in the Biomedical Engineering department at the University of Delaware and at Nemours/A.I. duPont Hospital for Children. She is currently investigating disease progression of several neurological disorders using preclinical and clinical Magnetic Resonance Elastography scanning combined with histopathological analysis of brain tissue. Her focus lies on adapting Magnetic Resonance Elastography for use on rodents to understand the biomechanics of the female brain in health and neurologic disease. She received her doctorate in Behavioral Neuroscience at the University of Delaware under the co-mentorship of Drs. Anna Klintsova and Tania Roth. During her graduate studies, Katrina evaluated the capacity for aerobic exercise to enhance white matter maturation in a preclinical model of Fetal Alcohol Spectrum Disorders from the ultrastructual to systems-levels. Her work merited awards from the Society for Neuroscience, Research Society on Alcohol, Fetal Alcohol Spectrum Disorders Study Group, International Society for Developmental Psychobiology, and a 2018 University of Delaware Woman of Promise award. While pursuing her Ph.D., Katrina also completed her MS in Neuroscience at the University of Delaware and founded a local Scientista Foundation chapter with the mission of supporting the advancement of women in STEM. Katrina received dual degrees in Comprehensive Science and Bioethics from Villanova University in 2017. She first developed a passion for research while working as a research assistant for Dr. Scott Lorch at the Children's Hospital of Philadelphia/University of Pennsylvania Research Institute where she studied the intersectionality of race, socioeconomic status, and accessibility to quality healthcare on disparities in pediatric health outcomes. She was a key contributor to the development of the CHOP Baby & Books program which supports language development in premature infants. In her free time, Katrina enjoys traveling, participating in water sports, and frequenting new restaurants.
Graduate Students
Tyler Williams
Biomedical Engineering
Tyler began his studies as a PhD student in Biomedical Engineering after graduating from Penn State in 2019 with a B.S in Biomedical Engineering and a B.S. in Mechanical Engineering. His research interests include osteoarthritis, degenerative disorders, and high field MRI. His current projects include developing pre-clinical magnetic resonance elastography procedures and anisotropic MRE data analyss. Tyler hopes to apply these modalities to study degenerative disorders in rodent brains. He is also a recipient of the Unidel Distinguished Graduate Scholars Award. Outside the lab, Tyler is an avid musician, golfer, and gamer.
Diego is a PhD student in the Biomedical Engineering department and completed his BS in Biomedical Engineering at Penn State University with a Minor in Engineering Mechanics. As an undergrad at PSU-Abington he was a two-season starter for the division 3 men’s varsity soccer team. Moreover, he collaborated with the Gait Optimization Lab at PSU-University Park in 2018 determining the effects of ankle stiffness in a neuro-musculoskeletal model of lower limb amputees. He is currently working on developing multi-excitation protocols for anisotropic MRE. Diego enjoys outdoor running, a multitude of sports, infrequently playing the guitar, and hosting events in which he shows off his cooking repertoire.
Kyra Twohy
Mechanical Engineering
Kyra is a PhD student in Mechanical Engineering at UD and a recipient of the Helwig Fellowship. She completed her BS and MS in Mechanical Engineering, focused on human biomechanics, from the University of Notre Dame and the University of Dayton, respectively. Her research interests include studying the forces that drive brain development and understanding how motor coordination is influenced by the brain’s mechanical properties. Outside of research, Kyra enjoys watching Notre Dame sports, photographing the new places she visits around the world, and keeping up with her quarantine hobby of bread baking.
Mary Kramer
Biomedical Engineering
Mary is a PhD student in the Biomedical Engineering department and completed her BS in Biomedical Engineering at University of South Carolina in May of 2020. Mary's interest in MRE started during her REU at University of Illinois - Urbana Champaign, where she worked with the Magnetic Resonance Functional Imaging Lab to isolate the effects of vasoconstriction and vasodilation on whole brain stiffness. She is currently studying the role of cardiovascular health on brain mechanical properties with aging using Magnetic Resonance Elastography. Outside the lab, Mary enjoys traveling (especially to visit her 10!! nieces and nephews in South Carolina), going to concerts, and making tiktoks for the Johnson Lab tiktok account (@ud_mnl).
Alexa Diano
Biomedical Engineering
Alexa is a PhD student in Biomedical Engineering at the University of Delaware. She graduated from Rowan University in 2020 with her Bachelor of Science in Biomedical Engineering and a minor in Mechanical Engineering. As an undergraduate, she worked on research involving the synthesis and mechanical characterization of injectable hydrogels for nucleus pulposus replacement. Currently, she is working on adapting MRE techniques to quantify relative displacement between the skull and brain for applications in traumatic brain injury. During her free time, Alexa enjoys reading, baking, and crafting.
Olivia Bailey
Biomedical Engineering
Olivia is a PhD student in Biomedical Engineering at the University of Delaware. She graduated in May 2021 from the University of Maryland Baltimore County (UMBC) with a Bachelors of Science in Mechanical Engineering and a Psychology Minor. At UMBC she was heavily involved in her Scholar’s Program CWIT (Center for Women in Technology) and in her work as an undergraduate teaching assistant for a First Year Engineering course. She has previous research experience working with the design optimization for miniature magnetic robots aimed to break down blood clots and fenestrate arachnoid cysts. She is currently working on characterizing the nonlinear properties of brain tissue for use in improving traumatic brain injury computational models. Outside of research, Olivia enjoys reading, traveling, spending time with her family, and cooking over bonfires on the beach.
Sabrina Vander Wiele
Biomedical Engineering
Sabrina is a PhD student in Biomedical Engineering at the University of Delaware. She graduated from The College of New Jersey (TCNJ) in 2023 with a Bachelor of Science in Biomedical Engineering. Her undergraduate research focused on the effects of space radiation and microgravity on bones using CT imaging. She is currently working on preclinical projects using MRE to understand female rat brain stiffness across their estrous cycle. In her free time, she loves hiking and exploring historic places.
Nick Pyontek
Biomedical Engineering
Nick is a PhD student in Biomedical Engineering at the University of Delaware. He graduated from The College of New Jersey (TCNJ) in 2023 with a Bachelor of Science in Physics. His undergraduate research focused on fabricating topographical optical microstructures in azobenzene polymer film. He is currently using MRE to investigate the correlations between Alzheimer Disease risk factors and mechanical changes in the microstructure of the brain. In his free time, he enjoys reading, watching soccer, and playing with his dogs.
Matthew Kroen
Biomedical Engineering
Matthew is a PhD student in Biomedical Engineering at the University of Delaware. He graduated from Bucknell University in 2023 with a Bachelor of Science in Biomedical Engineering and a minor in Mathematics. As an undergraduate, his research focused on developing a patient specific anatomical model for use in the treatment of Parkinson’s Disease. Currently, he is working on developing machine learning models to predict the stiffness of brain tissue for applications in computer modeling. In his free time, he enjoys reading, hiking, biking, and canoeing.
Undergraduate Students
Emma Zarate
Neuroscience & Psychology 2025
Emma Newton
Neuroscience 2025
Gabriella Dunay
Biomedical Engineering 2024
Cassidy Sweeney
Biomedical Engineering 2024
Abigail Caridi
Biomedical Engineering 2026
Alyssa Wronski
Neuroscience 2025
Lab Alumni
Alexis Merritt Research Coordinator
Alex Cerjanic Postdoctoral Researcher (currently at Massachusetts General Hospital)
Lucy Hiscox Postdoctoral Researcher (currently at University of Bath)
Grace McIlvain PhD in Biomedical Engineering, University of Delaware 2022 (currently at Columbia University)
Peyton Delgorio PhD in Biomedical Engineering, University of Delaware 2022 (currently working at Exponent)
Dan Smith PhD in Biomedical Engineering, University of Delaware 2022 (currently at Emory University)
Melissa DiFabio PhD in Biomechanics and Movement Science, University of Delaware 2021
Charlotte Chaze MS in Biomedical Engineering, University of Delaware 2018
Emily Magoon BS in Biomedical Engineering, University of Delaware 2021 (currently working at Hologic)
Rebecca Clements BS in Biomedical Engineering, University of Delaware 2021 (currently at Northwestern University)
Emma Tinney BS in Neuroscience, University of Delaware 2021 (currently at Northeastern University)
Ariel Hannum BS in Biomedical Engineering, University of Delaware 2020 (currently at Stanford University)
Paige Dickinson BS in Biomedical Engineering, University of Delaware 2020 (currently working at Terumo)
McKenna Grega BS in Biochemistry, Mansfield University; 2019 Undergraduate Research Scholar
Gabby Villermaux BS in Neuroscience and Nutrition, University of Delaware 2020
Ray Duda BS in Biomedical Engineering, University of Delaware 2019
Nana Marfo BS in Neuroscience, University of Delaware 2019
Cassie Cooper BS in Cognitive Science, University of Delaware 2019
Emily Ebeling BS in Physics, Truman State University; 2017 Center for Biomechanical Engineering Research REU Student
Constance Barfoe BS in Integrated Studies, Delaware State University; 2017 Center for Neuroscience Research REU Student
Alex Kulyk BS in Biomedical Engineering, University of Delaware 2017
Christian Thompson BS in Biomedical Engineering, University of Delaware 2017
