Meet our current graduate students. These brilliant minds are working on cutting-edge research in biology. Learn more about their research interests and contact information by scanning their name and image.
Afia Agyeman-Andoh
Thesis research topic: Primary cilia in glioblastoma tumorigenesis Mentors: Elena Silva, Dr. Desmond Brown Email: aa2523@georgetown.edu
Afia is a Ph.D. candidate in Silva lab. She worked in Dr. Desmond Brown’s lab at the National Institutes of health (NIH). She graduated from Virginia Commonwealth University in 2013 with a B.S. in Biology and a minor in chemistry. She is currently working on discovering novel therapeutics for glioblastoma (GBM) -the most common primary malignant CNS. Outside of lab, Afia enjoys learning the Akan language, being in nature and spending time with family and friends.
Arifa Ahsan
Thesis Research Topic: Developmental neurobiology and regenerative processes Co-Mentor: Dr. Elena Silva and Dr. Jeffrey Huang. Email: asa135@georgetown.edu
Arifa graduated from Brandeis University in 2015 with a B.S. in Biochemistry. Her undergraduate thesis at the Hedstrom Lab focused on protein degradation via small molecule hydrophobic tagging, and she designed compounds to target Bcr-Abl protein, the pathophysiological cause of chronic myelogenous leukemia. Following college, she was involved in a project on chromothripsis with David Pellman’s group at Dana-Farber Cancer Institute. (Chromothripsis is a newly discovered mutational phenomenon in certain cancer cells, characterized by extensive genomic rearrangements.) For her graduate work at Georgetown, she has decided to pursue her long-term interests in developmental neurobiology and regenerative processes and will be co-mentored by Dr. Elena Silva and Dr. Jeffrey Huang. Outside the lab, she enjoys theatre, books, art, and creative writing.
Charles Minsavage-Davis
Thesis Research Topic: Community Genetics. Mentor: Dr. Matthew Hamilton Email: cd1231@georgetown.edu
Charles is currently a Ph.D. student in Dr. Matthew Hamilton’s lab, studying plant-insect interactions. Before coming to Georgetown, he earned a B.S. in Environmental Science and an M.S. in Ecology and Restoration at Ohio State while pursuing international research in Fire ecology based in Scotland and Norway. In his free time, he enjoys exploring and hiking with his partner and their dog.
Meghan Bullard
Thesis Research Topic: Experience-dependent synaptic plasticity Mentor: Dr. Haiyan He Email: mrb339@georgetown.edu
Meghan graduated from Furman University in 2021 with a double major in Biology and German Studies. At Furman, she worked in the Freeman lab, which examines sexual differences in neuroinflammation, the gut microbiome, and behavior in response to a high fat diet. Her undergraduate thesis looked at sexual dimorphisms of microglia on a high fat, high sucrose diet in the hippocampus. She is passionate about bridging the gap between current scientific research and social issues with particular interest in the neurobiology of stress and experience. At Georgetown, she is excited to join the He lab which explores the effects of experience on neuroplasticity. In her free time, she enjoys biking, reading, traveling, and exploring the city.
Verena Conkin
Thesis Research Topic: Dolphin behavior Mentor: Dr. Janet Mann Email: vsl14@georgetown.edu
Verena is a Ph.D. student in Dr. Janet Mann’s lab. She graduated from Indiana University in 2017 with dual degrees in Biology (BS) and Theatre (BA) as well as a certificate in Underwater Resource Management. While at IU, she served as a research assistant and scientific diver with the Office of Underwater Science, focusing on the growth of endangered coral colonies on historic shipwrecks in the Dominican Republic. After graduating, Verena was a NOAA fellow at the Great Lakes Environmental Research Laboratory, and continued working in aquatic and marine sciences as a research assistant at the University of Vermont and Woods Hole Oceanographic Institution. Since joining the Mann lab at Georgetown in 2022, Verena’s research has focused on the interactions between the dolphin populations found in the lower Potomac River and Chesapeake Bay. When she’s not in the lab or on the boat, she enjoys cooking, live music, and hiking with her wife and their dog.
Mia Cozart
Thesis Research Topic: Neural regeneration and neuron-glia interaction. Mentor: Dr. Jeffrey Huang Email: mdc143@georgetown.edu TBA
Alp Demirhan
Thesis Research Topic: Development of the neurons in the inner ear. Mentor: Thomas Coate Email: md1857@georgetown.edu
Alp is currently a Ph.D. student at Dr. Coate’s lab. He earned his BS in Audiology from the Baskent University in 2019 and has two M.S. degrees one from Ege University in Neuroscience and the other from the University of Wyoming in Zoology&Physiology. At Georgetown, he’s been focusing on inner ear neurobiology. In his spare time, Alp enjoys trying new restaurants, spending time with his friends, and traveling.”
Dennis DiMaggio
Thesis Research Topic: Gene expression patterns in Staphylococcus aureus Mentor: Dr. Shaun Brinsmade Email: dad148@georgetown.edu
Originally from Southeast Virginia, Dennis graduated from Old Dominion University in the spring of 2018 earning his B.S. in Biology with a Minor in Music Performance. After completing his degree, he began working in the Biological Sciences Support Facility at ODU. While working there, he developed close connections with the research faculty on campus and eventually transitioned to working as a technician in the Daines lab on the Gram-negative, halophilic pathogen, Vibrio vulnificus, studying the effect of a Type II Toxin-Antitoxin System on growth. His specific interests include microbial pathogenesis, host-pathogen interactions, and the bacterial stress response. Away from the lab, Dennis enjoys trying new places to eat in DC, spending time with his cat, practicing French horn, cooking, and sipping a nice glass of whiskey at the end of a long day.
Marcelle Ferreira
Thesis Research Topic: Gene expression patterns in Staphylococcus aureus Mentor: Dr. Shaun Brinsmade Email: mcf126@georgetown.edu
Marcelle got her B.S. in Pharmacy at the Federal University of Espirito Santo, Brazil in 2013, and, subsequently, her M.S. in Microbiology at the Federal University of Rio de Janeiro, Brazil, in 2015. Before coming to the US, she worked as a Pharmacist for 5 years at the Brazilian Army. Now she is a Ph.D. student in the Brinsmade Lab where she is interested in understanding how branched-chain fatty acids, and therefore, membrane composition, regulates virulence in Staphylococcus aureus through the Sae RS Two-Component System.
Deborah J. George
Thesis Research Topic: Development of the neurons in the inner ear. Mentor: Dr. Thomas Coate Email: djw103@georgetown.edu
Originally from Brookline, MA, Deb graduated from Virginia Polytechnic and State University in 2015 earning her B.S. in Animal and Poultry Sciences with a dual emphasis in livestock and equine science. In 2019, she received her M.A. in Biology from American University, working in computational genomics with Dr. John Bracht. There she performed genomic and transcriptomic studies on the thermophilic worm, Halicephalobus mephisto (“The Devil Worm”), revealing adaptation(s) to its sub-terrestrial environment involving elevated heat. She then worked for two years as a mouse breeder for NIH at Janelia Research Campus. She has now joined the lab of Dr. Thomas Coate, and aims to further understand the molecular mechanisms and guidance cues directing type II SGN turning and OHC innervation.
Mara Heilig
Thesis Research Topic: Mosquito habitat adaptation. Mentor: Dr. Peter Armbruster Email: mch284@georgetown.edu
Ellen R. Jacobs
Thesis Research Topic: Dolphin behavior. Mentor: Dr. Janet Mann Email: erj22@georgetown.edu
Ellen received her Bachelor’s in Ecology, Behavior, and Evolution from the University of California, San Diego in 2016, where she completed an honors thesis on density estimations of Cuvier’s beaked whales using passive acoustic monitoring with the Scripps Institution of Oceanography. After graduating, she worked as a research intern at the Monterey Bay Aquarium Research Institute, the Smithsonian Tropical Research Institute, and Woods Hole Oceanographic Institute. In 2019 she received her Master’s in Zoophysiology from Aarhus University in Aarhus, Denmark, where she did her thesis on the active space of sperm whale social calls. Ellen came to Georgetown to begin her Ph.D. studies in 2019, where she uses a combination of behavioral ecology and bioacoustic techniques to understand the lives of bottlenose dolphins. Outside of her academic interests, Ellen enjoys reading, hiking, and traveling.
Grace Jeschke
Thesis Research Topic: Study of large-scale patterns of insects, mostly butterflies. Mentor: Dr. Leslie Ries Email: grj14@georgetown.edu
She is interested in climate change and butterfly ecology.
Rita Kosile
Thesis Research Topic: Immune responses to Giardia lamblia. Mentor: Dr. Steven Singer Email: rta18@georgetown.edu
Rita is a Ph.D. student in the Singer Lab. She received her Bachelor’s degree from the Federal University of Technology, Akure, Nigeria. She got her M.S. from Auburn University, Alabama where she worked on the Interaction of Chromobacterium species with Chytrid fungus in the Mendonca lab. She is now interested in the dynamics of infections investigating how the microbiome is influenced by Giardia lamblia infections. In her spare time, She enjoys cooking various Nigerian dishes and trying out American, Asian and Mexican recipes.
Katherine M. Kraft
Thesis Research Topic: Cell fusion and the control of meiosis. Mentor: Dr. Mark Rose Email: kmk314@georgetown.edu
Emma Lederer
Thesis Research Topic: Plant-insect interactions. Mentor: Dr. Martha Weiss Email: ekl71@georgetown.edu
Emma is a second-year Ph.D. student in Martha Weiss’ lab studying ecosystem engineering caterpillars. Her research is focused on understanding the cues that guide primary and secondary occupancy in caterpillar-built leaf shelters as well as other aspects of caterpillar behavior and ecology. Emma is a proud member of Georgetown’s Alliance of Graduate Employees (G.A.G.E.) and enjoys her work as a Teaching Assistant.
Haeli Lomheim
Thesis Research Topic: Neural induction in Xenopus laevis Mentor: Dr. Elena Silva Email: hjl63@georgetown.edu
Haeli Lomheim is from Petaluma, CA. She lived in Marin County for the last ten years and got a BS in psychology and a B.A. in chemistry from Dominican University of California. When Haeli graduated, she did my masters research in Dr. Meredith Protas’ lab in Biology, studying a nonmodel organism called Asellus aquaticus and looking for candidate genes for eye degeneration, pigmentation, and metabolism. Haeli is now working in Dr. Elena Silva’s lab here at Georgetown. She is interested in working in the industry in the future.
Shican (Claire) Li
Thesis Research Topic: Attachment mechanism of the intestinal parasite Giardia lamblia Mentor: Dr. Heidi Elmendorf Email: sl1453@georgetown.edu
Shican (Claire) received her BS degree from the University of New Haven and an M.S. from Brandeis University. She is now working on her Ph.D. degree in the Elmendorf lab studying the attachment mechanism of the intestinal parasite Giardia lamblia. She is particularly interested in investigating how Giardia responds to environmental cues to find its attaching site during infection, and especially, how Giardia interacts with intestinal mucus. She plans to explore these questions using biological and physical approaches. Besides science, Claire enjoys singing Beijing Opera, writing poetry, and playing Chinese zither occasionally.
Ursula Machi
Thesis Research Topic: Cell fusion and the control of meiosis. Mentor: Dr. Mark Rose Email: ujm2@georgetown.edu
Ursula graduated from Pennsylvania State University in 2016 with a major in biotechnology and a minor in microbiology. While there, she worked on crystallography studies of iron-sulfur cluster proteins under Dr. Squire Booker. She then went on to a research associate position at Carnegie Mellon University in the lab of Dr. Tina Lee, where she studied the mechanism of ER tubule fusion. She has now joined the lab of Dr. Mark Rose, and aims to further understand the process by which two cells become one. Outside of lab, Ursula enjoys cooking, traveling, and watching live music.
Meredith MacQueeney
Thesis Research Topic: Dolphin behavior. Mentor: Dr. Janet Mann Email: mem505@georgetown.edu
Meredith earned a B.S. in Marine Science and Environmental Studies from Eckerd College in 2019. As an undergraduate, she worked with the Eckerd College Dolphin Project on research aiming to enhance our understanding of the biology of bottlenose dolphins in Tampa Bay, Florida. At Eckerd, she undertook a study characterizing boater interactions with dolphins which was published in Human Dimensions of Wildlife. In the fall of 2019, she worked as a research assistant for the Shark Bay Dolphin Project (SBDP) in Western Australia where she began research centered around maternal investment. In the spring of 2019, she moved back to Florida for an internship with Mote Marine Laboratory’s Sarasota Dolphin Research Program. Meredith came to the Ph.D. program in Biology at Georgetown in 2021 to continue work with the SBDP. Her research interests include calf development and the role of mothers in maintaining tradition and culture in this wild dolphin population. Meredith hopes that her research will inspire public interest in marine conservation to help ensure that future generations will continue to learn from the fascinating lives of whales and dolphins. Beyond academics, Meredith enjoys cooking, yoga, live music, and the great outdoors!
Fabiana grew up in Tacna, Peru, before earning her Bachelor’s Degree in Biology from the Cayetano Heredia University in Lima. After completing her degree, Fabiana decided to pursue a graduate program in the USA, showing enthusiasm to understand biological problems through a biophysics approach. She graduated from Johns Hopkins University with a masters in Biophysics, and after finishing her master’s she continued working at JHU, studying pioneer transcription factors and nucleosome-protein interactions. She decided to pursue her passion for Microbiology in the Biology program at Georgetown and she is excited to pursue the Ph.D. as a member of Brinsmade lab. Her specific interests are in microbial nutrient sensing, host-pathogen interactions, and intracellular signaling for microbial survival. Fabiana enjoys painting, playing board games, exploring DC museums, and enjoying a glass of wine while cooking.
Zeeba Manavi
Thesis Research Topic: Neural regeneration and neuron-glia interaction. Mentor: Dr. Jeffrey Huang Email: zm114@georgetown.edu
Zeeba earned her B.S. in Biology from the University of Maryland. She continued pursuing her passion for science at Georgetown University, successfully completing her M.S. in Biochemistry. During her graduate studies in the laboratory of Dr. Cynthia Rosenthal, she investigated the role of DNA-binding protein inhibitor (ID3) in transdifferentiation of human fibroblasts to neural stem cells. Her thesis was presented at the University’s Tri-Annual M.S. in Biochemistry and Molecular Biology Poster Presentation, which earned her an Excellence in Internship award. Her interest in cellular reprogramming and neuroregeneration led her to the laboratory of Dr. Richard Schlegel where she focused on studying the signaling pathways involved in Conditionally Reprogrammed Cells (CRCs) propagated in culture media composed of Rho-kinase inhibitor with mouse 3T3 feeder cells. Zeeba is excited to be joining The Huang lab with an interest in studying neural stem/progenitor cell senescence in Multiple Sclerosis. Outside of the lab, Zeeba enjoys studying Japanese, rock climbing, and making fresh pasta
Juan Carlos Martinez-Cervantes
Thesis Research Topic: Learning and forgetting in Drosophila Mentor: Dr. Isaac Cervantes-Sandoval Email: jm3381@georgetown.edu
Juan Carlos earned a B.S. in Biotech Engineering at Instituto Politécnico Nacional in Mexico. His research at the Cervantes-Sandoval lab focuses on mechanisms of learning and forgetting using the fruit fly as a model organism.
Olotu Emmanuel is from Nigeria. He obtained his bachelor’s and master’s degrees in microbiology from the Federal University of Technology, Akure, Nigeria. He was a Graduate Teaching Assistant during his MSc and his thesis research focused on the valorization of agricultural wastes using Saccharomyces cerevisiae. After the completion of his master’s degree, he joined the Department of Microbiology, Adekunle Ajasin University, Akungba-Akoko, Ondo state as an Assistant lecturer and has always been fascinated by the concept of how microbial cells sense environmental conditions to alter gene expression. He is now interested in the role of inositol pyrophosphates in the regulation of the Target of Rapamycin Complex 1 (TORC1) via phosphate homeostasis and its connection to the PHO pathway in Yeast cells. Joining the Rolfes lab was a dream come true, knowing that he could learn and grow in a field he’s always been passionate about. Outside the lab, he loves traveling, playing table tennis, and cooking Nigerian delicacies.
Joan Reger
Thesis Research Topic: Neural regeneration and neuron-glia interaction. Mentors: Dr. Jeffery Huang and Dr. Meng Meng Fu Email: jfr59@georgetown.edu
Joan is a Ph.D. student in Huang’s lab where she studies microtubule dynamics in oligodendrocytes. She earned her B.S. in Biology at Emory University in 2017. While at Emory, she worked in the Wilkinson lab studying yeast prions and also worked with K-12 students in the Atlanta community through the educational outreach program Graduation Generation. Prior to coming to Georgetown, she completed a summer research project on TDP-43 in the Eisenberg lab at UCLA and a public health science internship at the USDA in Washington, D.C.Outside of the lab, Joan enjoys traveling, yoga, DIY projects, and watching The Office. Outside of the lab, Joan enjoys traveling, yoga, DIY projects, and watching The Office.
Prachi Shah
Thesis Research Topic: Mentor: Dr. Isaac Cervantes Sandoval Email: ps1246@georgetown.edu
Prachi earned a B.S. in Biology with minors in education and biological anthropology from Binghamton University in 2021. Her past research was done with Dr. Donald Wilson at the Nathan Kline Institute for Psychiatric Research. She focused on Alzheimer’s disease, specifically investigating the connection between olfaction and genetic markers in mice. She also worked on a project investigating the effects of fetal alcohol syndrome on sleep deprivation. Prachi is excited to continue her research in memory, specifically the process of forgetting here at Georgetown. In her free time, Prachi enjoys reading, knitting/crocheting, and spending time with friends.
Henry Stevens
Thesis Research Topic: Migratory Birds and Conservation. Mentor: Dr. Peter Marra Email: hcs58@georgetown.edu
Henry graduated from Tufts University (Roll ‘Bos) in 2019 with a joint BS in Biology and Environmental Science. He grew up in Exeter, NH, where he discovered his passion for ornithology. He LOVES birds, and his desire to understand their ecology is what gets him out of bed in the morning (#ForTheBirds). Henry’s research interests lie at the intersection of conservation ornithology and tropical ecology, and his past research has focused on the breeding biology and dispersal of Gray Vireos (Vireo vicinior) in New Mexico, the use of remote audio recorders for surveying cryptic species in the Amazon, improving the conservation site network for migratory shorebirds in the Americas, and uncovering the life histories of Andean Cock-of-the-rocks (Rupicola peruvianus) and other understudied species in the cloud forests of Ecuador. At Georgetown, Henry plans to study the full annual cycle of Neotropical migratory wood-warblers, and use integrated population models to pinpoint factors driving their declines. With over 3.2 billion individual birds lost in North America since 1970, understanding and addressing the threats faced by these species is paramount for mitigating further declines.pecies in the cloud forests of Ecuador. At Georgetown, Henry plans to study the full annual cycle of Neotropical migratory wood-warblers, and use integrated population models to pinpoint factors driving their declines. With over 3.2 billion individual birds lost in North America since 1970, understanding and addressing the threats faced by these species is paramount for mitigating further declines.
Samantha L. Sturiale
Thesis Research Topic: Mosquito habitat adaptation. Mentor: Dr. Peter Armbruster Email: sls366@georgetown.edu
Sam is a Ph.D. student working in Dr. Peter Armbruster’s lab. Sam graduated in 2019 from the University of Virginia with a B.S. in biology, specializing in environmental and biological conservation. During her time at UVA, she served as an undergraduate researcher in Dr. David Parichy’s lab studying the genetics of pigment pattern formation in zebrafish. As an undergraduate, she also participated in a summer REU program at UVA’s Mountain Lake Biological Station where she investigated self-medication behaviors within the ant seed dispersal mutualism (myrmecochory). She then earned a Master of Science by research in biology at the University of St Andrews in the UK for her thesis work studying the effects of social plasticity within and across generations in a rapidly evolving population of Hawaiian field crickets. At Georgetown, she is interested in exploring how temperature influences survival, energy usage, and the development of insects that enter a state of dormancy (diapause) to survive winter. She hopes this work will help us better understand how important temperate insects will respond to projected increases in average winter temperature and frequency of extreme events such as heatwaves. She will explore this topic using an important disease vector, the Asian tiger mosquito (Aedes albopictus). Outside of lab, Sam enjoys reading, spending time with her pet cat (Kitty), and playing board games with friends.
Malavika Sugumar
Thesis: Development of the neurons in the inner ear. Mentor: Dr. Thomas Coate Email: ms4828@georgetown.edu
Malavika graduated from California State University, Northridge with a BS in microbiology before joining the Ph.D. program here at Georgetown. As an undergrad, she branched out from her major and decided to gain research experience at a developmental biology lab instead, where she helped characterize the role of different transcription factors that were involved in the early development of neural crest cells in chicken embryos under Dr. Crystal D. Rogers. Her current work is focused on studying development and spontaneous activity in auditory neurons. In her free time, she enjoys dancing, exploring the city, cooking, and spending time with friends.
Brady Thexton
Thesis Research Topic: Plant-insect interactions. Mentor: Dr. Martha Weiss Email: bt495@georgetown.edu
Brady is a Ph.D. student working in Dr. Martha Weiss’ lab. Brady graduated from Drew University (Madison, NJ) in 2020 with a B.S. in environmental science and a minor in creative writing. During their time at Drew, Brady worked as a research assistant in Dr. Tammy Windfelder’s lab studying the population dynamics of small mammals in response to white-tailed deer exclusion in regenerating forest habitats and Dr. Alex Bajcz’s lab studying the reproductive ecology of native and non-indigenous Rubus. They also worked part-time to manage non-indigenous plant species in the university’s forest preserve. At Georgetown, Brady’s research focuses on clarifying the relationship between non-indigenous plant species and native insect herbivore communities. As non-indigenous plants continue to spread across the globe with no signs of stopping, it is essential that we understand how the ecological interactions between these groups change over time. Brady is exploring these relationships using species in the grape family (Vitaceae) such as the non-indigenous porcelain berry (Ampelopsis glandulosa) that was brought to D.C. in the 1870s.
Outside of lab, Brady enjoys going for walks with their pandemic puppy, Wendell, and drinking copious amounts of coffee.
Cesar Velez-Penaloza
Thesis Research Topic: Neurogenesis in Xenopus laevis Mentor: Dr. Elena Silva Email: cdv16@georgetown.edu
Cesar graduated from the University of Maryland-College Park in 2016 with a BS in Animal Sciences and a B.A. in Spanish. His plans were to go to Vet school and worked at the campus farm and animal wing at UMD. After graduation, he worked as part of the husbandry staff at NIH. From previous animal work, he decided that vet medicine was not for him. During the completion of his degrees, he took an experimental embryology class which sparked his interest in research specifically in developmental biology. To get more knowledge of current lab techniques he finished a Biotechnology Certificate from Montgomery College. For his graduate work at Georgetown, he had decided to join Elena Silva’s lab. Outside of the lab, he tries to be as social as possible to have a balanced life, he loves trying new foods, and learning about different cultures and people.
Maggie M. Weng
Thesis Research Topic: Biosignature detection. Mentor: Dr. Sarah Johnson Email: mw1144@georgetown.edu
Maggie Weng is a Ph.D. student with the Johnson Biosignatures Lab. Maggie graduated from Washington University in St. Louis with a degree in environmental earth science and a minor in writing, and was a member of the Pathfinder program led by Raymond Arvidson. She completed an REU internship with the Johnson lab during her undergraduate degree, as well as an internship at NASA Goddard Spaceflight Center where she studied the spaceflight compatibility of the MinION portable DNA sequencer. Her research interests include understanding the ecology and community structure of extreme environments, as well as an agnostic understanding of life detection. She loves traveling and fieldwork and is always interested in looking for intersections of astrobiology work with relevant environmental problems. When not working in the lab you can find her hiking, knitting, or writing.
Emily Williams
Thesis Research Topic: Migratory Birds and Conservation. Mentor: Dr. Peter Marra Email: ejw75@georgetown.edu
Emily is an avian ecologist that has been working with birds for the last ten years. She comes to the Marra lab from working for the National Park Service in Alaska, where she studied the movements, ecology, and behavior of Denali’s residents and migratory birds. Prior to working at Denali National Park and Preserve, Emily completed her MSc at Kansas State University investigating the patterns and mechanisms to within-season breeding dispersal in grassland sparrows. Emily received her BSc in Wildlife Ecology and Conservation and B.A. degree in English literature from the University of Florida. Emily’s research interests center in migration ecology, with a particular interest in the evolutionary and ecological processes that give rise to variation in migratory behavior. Emily’s Ph.D. research will focus on understanding the drivers that lead to different migratory strategies between Palearctic and Nearctic migratory birds. Beyond her academic interests, Emily is passionate about outreach and the accessibility of science, and never foregoes an opportunity to get people excited about birds.
