Current Graduate Students
Julie Krzykwa, MS 2017, PhD 2020
My name is Julie Krzykwa and I am working on my PhD in Biology in the Jeffries Lab. I originally hail from Milford, CT, but spent seven years living in Florida before coming to TCU. I received my B.A. in Biology from New College of Florida in 2012, and spent three years working for the Environmental Protection Agency before coming to TCU to pursue my MS degree. My time at the EPA introduced me to environmental toxicology research through projects such as “Aquatic Species Toxicity Translators: Amphibian exposures to Bifenthrin” and “Developmental Toxicity of Louisiana Crude Oiled Sediment to Zebrafish”. These projects led me to become interested in helping develop more humane methods for aquatic toxicology testing. My thesis and dissertation research is part of the Animal Alternatives Project, looking at the fathead minnow fish embryo toxicity test as a replacement for current testing procedures and at the use of sub lethal endpoints, such as growth related gene expression and developmental abnormalities, to improve the sensitivity of the fish embryo toxicity test. When not in the lab, I am usually baking, creating something, or attending live music somewhere in DFW. When I lived closer to the ocean I spent as much time as possible SCUBA diving or just hanging out at the beach.
Leah Thornton Hampton, MS 2015, PhD 2020
My name is Leah and I completed my Master's degree in the Jeffries lab in August 2015. I have been involved in research since my sophomore year at Miami (Ohio) University, where I was also a varsity swimmer. During my time as a M.S. student at TCU, my research focused on how emerging contaminants can have different effects in adult and early life stage organisms. This research served as the basis of my thesis "Timing is Everything: Exploring the Differential Reproductive Effects of PBDE-47 on Adult and Early Life Stage Fathead Minnows". I am currently attending the University of North Texas to pursue a PhD in Biology, but am co-advised by Dr. Barney Venables (UNT) and Dr. Jeffries and much of my dissertation research, which focuses on the effects of early life stage thyroid disruption on immune system development, will be conducted in the Jeffries lab. Ultimately, I hope to pursue a career in academia. When not in the lab, I enjoy being outdoors, particularly if it involves the water. If I can get away long enough, I also like to travel and scuba dive if I get the chance!
Lynsey Malin, MS 2020
Hi! My name is Lynsey Malin. I completed undergraduate degrees in Biology and Entrepreneurial Management at TCU in 2018 before starting as a graduate student in the Jeffries lab. As an undergraduate, I conducted a research project focusing on the relationship between estrogens and immunity as a part of Dr. Jeffries’ endocrinology course. I will be continuing the same line of research for my Master’s thesis, specifically utilizing an antiestrogen exposure to study the impact of estrogen levels on immune function in female fathead minnows. In my free time I enjoy cooking, traveling, and trying new restaurants. After graduate school, I will be attending medical school! Ultimately, I hope to practice as a physician and conduct clinical research.
Former Graduate Students
Abbey Johnson, MS 2019
Abbey began her MS degree at TCU after graduating from the University of Texas with a BS in Marine and Freshwater Biology. As an undergraduate, Abbey gained research experience in fish physiology while working on a research project studying the effects of hypoxia on the oxygen carrying capacity in red drum. As an MS student, Abbey was co-advised by both Dr. Jeffries and Dr. Matt Hale and worked on a project aimed at connecting developmental thyroid disruption in fathead minnows to impaired reproductive success. Specifically, she analyzed brain transcriptomes from males exposed to thyroid disruptors during early development to identify possible mechanisms that lead to the observed reduction in fecundity. Her work provided evidence suggesting that thyroid disruption during early life stages has the capacity to alter various aspects of brain development, including neurogenesis and brain sexual differentiation. It is hypothesized that such changes lead to alterations in male reproductive behavior and subsequent reductions in fecundity. In her free time Abbey enjoys traveling, reading, and being with friends and family. She is currently on the job market!
Kyle Roush, MS 2018
Kyle Roush began his research in the Jeffries lab as a sophomore and recently graduated with an MS degree. As an undergraduate, Kyle completed a Senior Thesis project titled Enhancing the fish embryo toxicity test: Growth, developmental abnormalities and gene expression as additional endpoints, which focused on using sublethal measures as test endpoints for a relatively new alternative toxicity testing method, the fathead minnow fish embryo toxicity test. As a graduate student, his research focused on improving endocrine disruption screening assays by identifying biological factors that influence test outcome. Specifically, his MS thesis work sought to understand how the reproductive status of fish used in such assays influences their response to compounds that interfere with sex steroid hormone signaling. Kyle currently serves as an adjunct instructor for the Department of Biology's Contemporary Issues in Biology course.
Peter Bruns, MS 2017
Peter joined the Jeffries lab after graduating with a Zoology degree from Texas A&M where he conducted research in a plankton ecology lab. Peter graduated with a MS degree in Biology from TCU in 2017. His thesis project examined the effects of model thyroid disruptors on reproductive endpoints in fathead minnows and showed that early life stage exposures to thyroid inhibitors impair reproductive success later in life. Peter is now a PhD student in the Department of Environmental Science at Baylor University. In his free time, he likes to play with his dog, watch sports, look at funny pictures on the internet, and SCUBA dive whenever the chance arises.