Lipofuscin is an autofluorescent (AF) pigment formed by lipids and misfolded proteins, which accumulates in postmitotic cells with advanced age. Here, we immunophenotyped microglia in the brain of old C57BL/6 mice (>18 months old) and demonstrate that in comparison to young mice, one-third of old microglia are AF, characterized by profound changes in lipid and iron content, phagocytic activity, and oxidative stress. Pharmacological depletion of microglia in old mice eliminated the AF microglia following repopulation and reversed microglial dysfunction. Age-related neurological deficits and neurodegeneration after traumatic brain injury (TBI) were attenuated in old mice lacking AF microglia. Furthermore, increased phagocytic activity, lysosomal burden, and lipid accumulation in microglia persisted for up to 1 year after TBI, were modified by APOE4 genotype, and chronically driven by phagocyte-mediated oxidative stress. Thus, AF may reflect a pathological state in aging microglia associated with increased phagocytosis of neurons and myelin and inflammatory neurodegeneration that can be further accelerated by TBI.

Catherine Wraback, '23 chemical engineering, traditional track and AIChE co-president 

Meet Catherine Wraback, a senior in the chemical engineering traditional track, President of the AIChE student organization, and a CWIT (Center for Women in Technology) Scholar. Catherine was also the President of the American Institute of Chemical Engineers (AIChE) ChemE Jeopardy team which won first place at the 2022 national competition. She will be heading to GE Aerospace to become a part of the Edison Engineering Development Program. Take it away, Catherine! 

Catherine Wraback, chemical engineering '23, poses in the GE Aerospace office after accepting the Edison Engineering Development Program offer. Image courtesy of Wraback.

Q: Why did you choose UMBC?

The Chemical, Biochemical, and Environmental Engineering (CBEE) department at UMBC has a strong sense of community, which I experienced firsthand during a campus tour. I was impressed by the friendly and welcoming atmosphere of the department, and it was clear that the faculty and students form a close-knit group. One of the main reasons why I was attracted to UMBC is the family-like environment within the CBEE department, where professors and staff not only care about the academic success of their students, but also their personal well-being. This dynamic ensures that students receive the support they need to thrive both personally and professionally.

Q: Tell us about someone in the department who has inspired you or supported you & how did they do it?

Dr. Raikar and Dr. Castellanos are remarkable professors at UMBC, who go above and beyond to support their students. Dr. Raikar is known for her open-door policy, which makes her approachable to all students, and she is always willing to lend an ear and provide guidance on any topic. Her classes are not only inspiring, but also challenging and intellectually stimulating, which keeps students engaged and motivated.

Dr. Castellanos is an advocate for the needs of her students and encourages them to approach problem-solving from a holistic perspective, considering the broader impact on society. Her passion for thermodynamics is contagious and inspires her students to develop a deeper understanding of the subject matter. 

Both Dr. Raikar and Dr. Castellanos are instrumental in running the American Institute of Chemical Engineers (AIChe) at UMBC. Their guidance and support ensure that the student organization runs smoothly and provides a valuable platform for students to develop their leadership skills, network with peers and professionals, and participate in various academic and social events.

Q: What do you love about your academic program?

The chemical engineering bachelor's program at UMBC offers a variety of tracks, which allows students to tailor their education to their specific interests and career goals. One of the most beneficial aspects of the program is the ability to choose elective courses, which provides students with the flexibility to customize their curriculum and explore various topics in depth. I particularly appreciated the ample opportunities to take labs, which provided me with hands-on experience and helped me develop my practical skills. Additionally, the program encourages students to design their own projects, which fosters creativity and innovation, and provides a platform to apply theoretical knowledge in real-world scenarios.

Q: What clubs and orgs are you a part of and why? How was that experience?

I have had the privilege of serving as the President of the AIChE chapter at UMBC, as well as being a part of the Jeopardy Team, which has won at both the regional and national level. I am on the women's ultimate frisbee team at UMBC and attend practice twice a week. Being involved in these extracurricular activities has taught me valuable lessons in teamwork, conflict resolution, and leadership. Through these experiences, I have learned to approach disagreements with empathy and respect for diverse perspectives, while also managing multiple responsibilities and growing as a leader.

Moreover, being part of these teams has given me the opportunity to have fun and connect with my peers outside of the classroom. I have formed close personal connections with my teammates and learned a lot from their unique perspectives and experiences. These extracurricular activities have also taught me the importance of compassion and understanding towards others, and the value of taking time to enjoy the company of friends.

Q: What would you tell others who are in your shoes at UMBC?

I strongly encourage everyone to get involved in extracurricular activities and events on campus. Don't hesitate to attend office hours, ask questions, and engage with your professors, as they are a valuable resource and can provide guidance and support beyond the classroom. Additionally, attending student organization meetings and other events is an excellent way to meet new people, build connections, and broaden your horizons. Getting involved in extracurricular activities can help you build a well-rounded skill set that will serve you in your future endeavors.

2022 AIChE ChemE Jeopardy National Championship team and their advisor (l-r): Max Bobbin, Catherine Wraback, Dr. Neha Raikar, Colin Jones, and Pavan Umashankar. Image courtesy of Wraback

We are proud to announce that the Chemical, Biochemical, Environmental Engineering Department was acknowledged for our involvement in the Fall 22 STEM Expo and Fall Fair, as well as for representing the COEIT department in the First Lego Program STEM Education Research at the Annual Annapolis Area Christian School STEM Program.

We extend our gratitude to the Annual Annapolis Area Christian School system, the COEIT department, and all the students, staff, and faculty members from CBEE for their generous support and contributions.

Tyler Josephson’s lab sits off a main corridor in the department of chemical, biochemical and environmental engineering at UMBC. Open the door, though, and you’ll see nary a beaker, chemical closet, or lab coat. Inside, a few computers sit on tables. You might see equations scrawled on the white board or a few students poring over lines of code.

Using this modest setup, Josephson has launched an ambitious project to equip computers to make scientific discoveries—starting in the realm of chemistry. This March he won a prestigious NSF CAREER award to advance the project.

The goal of the work is ultimately to speed up the process of science, which should in turn give humanity new knowledge and tools to face down big challenges such as climate change and environmental degradation.

As Josephson and his students dive into the work, they are bringing together techniques from across mathematics, computer science, and chemical engineering. Their first step is to translate chemical theories into a rigorous mathematical language that a computer can understand.

Math as the language of science

In 1623, the Italian natural philosopher Galileo Galilei wrote an essay in which he described nature as a book written in “the language of mathematics.” Many scientists since have puzzled over the mysterious power of math to describe physical phenomena.

Josephson and his students are tapping into this power. They are using a tool developed by researchers at Microsoft called the Lean theorem prover. Lean is both a computer language and a program for checking each step of a rigorous mathematical proof.

“Formal proofs, which are verified by a computer, differ from the informal, handwritten versions often used by scientists,” says Josephson. Informal proofs are easier to write, but they usually skip logical steps, assuming a human reader will have the knowledge and skill to follow along. This means that errors can creep in undetected.

On the other hand, if a proof has been written and checked in Lean, it is guaranteed to be correct as long as the stated assumptions are true.

A community of Lean programmers

Lean has a dedicated community of volunteer developers who have built a large library of mathematical proofs, each of which can then serve as a building block for more complicated proofs. They aim to digitize mathematics, starting with the entirety of the undergraduate math curriculum, which will lay the foundation for formal proofs in advanced modern mathematics.

Josephson plans to build a similar library with formally correct derivations in science and engineering, starting with chemical concepts such as the thermodynamic behavior of gases and of molecules sticking and unsticking from surfaces.

He and his students describe their approach in a first paper on the subject, and are in the process of submitting it to journals.

The power of the work will multiply as more of the foundations of science are translated into Lean, so a large part of the team’s work will also be to recruit, inspire, and train fellow proof creators. They will hold workshops to showcase Lean for scientists and engineers, and they plan to create fun and educational games that will teach Lean-programming skills to newcomers.

“I’m really excited to share this tool with students and the scientific community,” Josephson says.

Building better scientific computing tools

Josephson’s goal to formally verify scientific theories isn’t just an intellectual exercise—it’s a means of building better tools for better science. One such tool he plans to create with NSF CAREER award support is Lean-based computer software that can simulate the behavior of molecules under a range of conditions. 

Scientists often use such software to test theories as an alternative to physical experiments. It can be easier to run simulations of reactions on a computer, for example, than to mix real chemicals again and again, and some molecular phenomena may happen so fast, or under such extreme conditions, that current experimental tools cannot capture them.

However, bugs can mar the performance of the software. For example, starting in 2011, a hidden coding error fueled a seven-year “war over supercooled water,” in which two scientific groups disagreed about what happens to ultrapure water when it is cooled significantly below the freezing point of normal water, and then suddenly crystallizes.

Code written in Lean is unique from that written in the programming languages commonly used in scientific computing, since it can be provably free of such math errors, Josephson says. 

As more scientists and engineers learn to write code and proofs in Lean, others will be able to write bug-free software for applications as diverse as weather forecasting, drug discovery, and predicting material performance.

“AI scientists” who reason on their own

Ultimately, Josephson hopes to use a Lean-based library of scientific knowledge to train computers as fellow scientists. For example, large language models, such as the recently popularized ChatGPT, might be trained on a library of scientific proofs and gain the ability to “autocomplete” proofs on their own, translate informal proofs from the literature into formal ones, and even discover entirely new scientific theories, which could then be checked for correctness by Lean.

A tool like this might revolutionize science. In Galileo’s time, a single person could master large portions of human scientific knowledge, but now scientists usually go to school for decades to become experts in a tiny subfield, Josephson says.

AI scientists capable of digesting a database of thousands of scientific proofs in multiple disciplines might draw connections across them to reveal new discoveries. “Such a tool could lead to an AI-powered Renaissance in interdisciplinary scientific discovery,” says Josephson.

While such lofty goals remain in the future, Josephson and his students are energized by the possibilities. As they embark on an exciting scientific journey, they are thrilled to bring as many people as possible along on the ride.

Joana Hernandez

Degree: B.S., Chemical Engineering, biotechnology & bioengineering track
Hometown: Hyattsville, MD
Post-grad plans: Applying to biochemical engineering Ph.D. programs

McNair Scholar Joana Hernandez is a research enthusiast who found her interest in scientific exploration and mentorship while at UMBC. Since 2019, Hernandez has worked as a research assistant in the lab of Fernando Vonhoff, assistant professor of biological sciences. The lab uses fruit flies as a model to study human neurological diseases. It was in Vonhoff’s lab where she realized that there were opportunities to turn her love of learning into a career in research. 

Hernandez has taken her interest in conducting research to the next level by helping to guide fellow students who may be unfamiliar with the academic research process. As a teaching fellow in the McNair Scholars Program, Hernandez led workshops in a class dedicated to teaching students how to develop research proposals. During these workshops, she presented on topics ranging from how to give a research presentation to how to apply to Research Experiences for Undergraduates (REUs). 

Hernadez shares that she’s proud to be a McNair Scholar. “As a first-generation college student, it can be difficult to navigate academic spaces and obtain resources on applying to graduate programs,” Hernandez says. “McNair welcomed me with open arms and helped grow my confidence by providing me with opportunities to conduct research and present at national conferences.”

Has there been a mentor or fellow student who influenced your time at UMBC?

“My mentors Fernando Vonhoff and María Célleri, assistant professor of gender, women’s, and sexuality studies, have both had a positive influence on me. As a first-generation college student, I was unaware that undergraduates could participate in research or present at research conferences. When Dr. Vonhoff enabled me to join his lab my freshman year, it opened the doors to a lot of future opportunities. I am very grateful to have had a research mentor that was so understanding and encouraging.

“Dr. Celleri, my McNair mentor, is someone I can always count on to give me advice about navigating academic spaces as a Latina, and how to balance my life between my immigrant household and school. I appreciate all the wisdom I have gathered from her.”

What academic achievement are you most proud of?

“I am most proud of when I presented the research I did in the Vonhoff lab at the 2019 Annual Biomedical Research Conference for Minoritized Scientists (ABRCMS). That was the first time that I had attended a national conference and flew out to the West Coast. It was an eye-opening experience being able to see other undergraduate researchers from diverse backgrounds who were also just as passionate about communicating their work.”