OSCAR Excellence Award Winners – OSCAR Celebration of Student Scholarship and Impact

Multiscale Indentation-based Mechanical Characterization for Advanced Alloys Suitable for Aeroengine Applications

Author(s): Mariah Tammera

Mentor(s): Dr. Ali Beheshti, Department of Mechanical Engineering and Shaheen Mahmood, Graduate Student Advisor

Abstract

Multiscale indentation is a reliable method used to extract basic mechanical properties from
materials, particularly structural metals and alloys. Knowing and understanding the mechanical
properties is critical for engineers to effectively and safely design structures and components
based on specific environments, applications, or loads the materials will be subjected to.
Although indentation techniques have been previously utilized to determine basic mechanical
properties, such as elastic modulus, extensive progress has not been made towards the ability to
employ multiscale indentation for extracting advanced mechanical properties (e.g. creep
parameters and fracture toughness properties) in a reliable manner that produces results closer to
the bulk of the material. This project aimed to evaluate creep and fracture toughness properties
for Inconel 718 by utilizing micro-indentation techniques at room temperature. Analysis of the
material microstructure occurred via the use of the Scanning Electron Microscope (SEM). Due to
the limitation of conducting research in one semester, the learning objectives fulfilled were
performing indentation tests to extract basic mechanical properties (i.e. hardness values and
elastic modulus values) and conducting SEM analysis on the indentation site to evaluate the
success of the indentation tests and note observations about the material. Moving forward, future
work will concentrate on building upon the exploration of indentation techniques at room and
elevated temperatures to improve current ability to determine advanced mechanical properties of
material in an efficient and reliable manner.

Audio Transcript

Hi everyone, my name is Mariah Tammera. This fall, I was working under Dr. Ali Beheshti and
Shaheen Mahmood in the Tribology and Surface Mechanics Lab on Multiscale Indentation-based
Mechanical Characterization for Advanced Alloys Suitable for Aeroengine Applications.
Multiscale indentation is a reliable method used in the field to extract basic mechanical
properties from materials, such as the elastic modulus value, by understanding the relationship
between the indentation load versus penetration depth. However, extensive progress has not been
made towards the ability to employ multiscale indentation for determining advanced mechanical
properties, such as creep parameters and fracture toughness values, to acquire data that is reliable
and closer to the bulk of the material. This project intends to focus on evaluating creep
parameters and fracture toughness values for Inconel 718 by utilizing micro-indentation
techniques at room temperature. After the indentation tests are concluded, the Scanning Electron
Microscope will be utilized to analyze the indentation site. As you can see, Figures 1 and 2
showcase the equipment used in this project.
Before beginning any lab work, I worked on a literature review to learn about creep deformation
and what the fracture toughness of a material is. I conducted a literature search with the guidance
of Dr. Beheshti, to learn about what some of the commonly used experimental methods to extract
creep and fracture toughness are. From this preliminary literature search, it becomes clear that –
based on the findings – the literature has limited research on utilizing multi-scale indentation
techniques to determine creep parameters and fracture toughness properties at both room
temperature and elevated temperatures.
An indentation site matrix is a conventionally utilized technique to systematically map out
measurement locations on the sample surface. On the left, Figure 3 represents a 5×4 matrix that
was used to map out 20 places on the sample surface where the indentation tests will occur. As
noted on my slides it’s important that the location chosen for these indentation tests should be on
a smooth, flat area free of holes, pits and away from the edges of the sample.
Figure 4 represents an example of one of the micro-indentation curves obtained from one of the
20 indentation tests with indentation load on the y-axis and the penetration depth on the x-axis.
I’d like to point out the green box around the horizontal line up on the top right, which indicates
that the indentation load is constant here for 5 seconds.
From the 20 indentation tests, an elastic modulus value and hardness value were derived using
the Anton Paar Indentation software. The average elastic modulus value found was
approximately 160.04 ± 2.04 GPa and the average hardness value found was approximately 2.46
± 0.09 GPa.
After the indentation tests were successfully finished, the sample was taken and analyzed under
the SEM. Figure 5 is a close-up of one indentation sites, showcasing the square pyramid-shaped
Vickers tip and that the Vickers tip is sharp enough due to the precise diagonal lines across the
indentation site. Figures 5 and 6 are indicative of a successful indentation site due to minimal
plastic deformation, as we see minimal surface features, like raised lines or deformation bands
around the indentation site. Lastly, there is no visible cracking along the edges and outer corners
of the indentation site, which signifies that Inconel 718 is more of a ductile material.
Due to the limitation of conducting research in one semester, the learning objectives fulfilled
were performing indentation tests to extract basic mechanical properties and conducting SEM
analysis on the indentation site. Despite not completely fulfilling the projective objectives, the
results tell us that exploring multi-scale indentation techniques is a promising method to
determine advanced mechanical properties at room and elevated temperatures to obtain values
that are reliable and closer to the bulk of the material. The advanced mechanical properties
gleaned will only benefit future researchers and engineers regarding material selection in a
variety of field, particularly aerospace.
I’d like to thank George Mason University’s Undergraduate Research Scholars Program at the
Office of Student Creative Activities and Research for the funding that allowed me to contribute
to this project, and I’d also like to thank Dr. Beheshti and Shaheen for all of the mentoring,
training, and support they have each given to me. They are both dedicated professionals, and it
was a pleasure to work with them.
Lastly, these are my references. Thank you very much for your attention.

College of Science OSCAR Undergraduate Research Scholars Program (URSP) - OSCAR

Novel Biomaterial for Triple Negative Breast Cancer Dual Drug Immunotherapy Nylon-66 Affinity Thread

Author(s): Grace Lee

Mentor(s): Alessandra Luchini, College of Science

Abstract

Triple-negative breast cancer (TNBC) presents poor outcomes and relapse following chemotherapy. Joint delivery of anti-programmed cell death ligand 1 (PD-L1) and immune recruiting protein Chemokine Ligand 9 (CXCL9) has shown to be an effective immunotherapy for TNBC. Nylon, a synthetic polymer used in surgical threads, is promising for dual drug delivery due to its biocompatibility and drug-loading capabilities. Functionalizing Nylon 6,6 with Cibacron Blue F3G-A facilitates drug loading. This project assessed the functionality of Nylon 6,6 dyed with Cibacron Blue as a vehicle for dual anti-PD-L1 and CXCL9 TNBC immunotherapy.
Nylon 6,6 was dyed with Cibacron Blue and loaded with anti-PD-L1 antibody Atezolizumab (10 ng/µl) and CXCL9. It was stitched onto the breast tumor site of syngeneic (BALB/c) mice with ~1 cm-sized tumors from the 4T1 cell line. Mice were sacrificed three days post-implantation. Tumors were harvested for immunohistochemistry (IHC) analyses, applying biomarkers for apoptosis and immune cell infiltration. DAB and Hematoxylin staining imaged and characterized drug activity.
The study demonstrated that the thread induced immune cell infiltration and increased tumor cell apoptosis. Results indicate that Nylon 6,6 functionalized with Cibacron Blue is an effective biomaterial for targeted drug delivery. Future work includes confirmation of CXCL9 chemotactic abilities after release from the affinity thread and quantification of immune infiltration.

Audio Transcript

Hello! My name is Grace, and my project is on “Novel Biomateiral for Triple Negative Breast Cancer Dual Drug Immunotherapy Nylon-66 Affinity Thread.”
Triple-negative breast cancer (TNBC) is a leading cause of cancer mortality in women.1 TNBC cells upregulate programmed cell death ligand 1 (PD-L1), receptors that suppress immune recognition
Joint delivery of anti-PD-L1 and immune recruiting protein Chemokine Ligand 9 (CXCL9) has shown to be an effective immunotherapy treatment for TNBC. Anti-PDL-1 drug block the binding site of PDL-1 receptor on tumor cell and function as stimulator for immune cells to recognize tumor cell and kill it. CXCL9 function as immune cell chemoattractant that entices immune cells to the tumor site
Nylon, a synthetic polymer commonly used in surgical threads, shows promise as a vehicle for dual drug delivery due to its excellent biocompatibility and chemical stability. Moreover, its extensive porous structures and high aggregation capability greatly increases its drug-loading capacity. Nylon can be functionalized with Cibacron Blue F3G-A, which is a reactive textile dye that increases Nylon’s reactive sites while reducing non-specific adsorption, improving drug release accuracy and reducing toxicity. This project assesses the functionality of Nylon 6,6 as a vehicle of dual anti-PD-L1 and CXCL9 TNBC immunotherapy.
Nylon 6,6 was dyed with Cibacron blue and loaded with anti-PD-L1 antibody Atezolizumab (10 ng/ul) and immune cell chemoattractant CXCL9. The loaded thread was stitched onto the breast tumor site of the syngeneic (BALB/c) mice harboring ~ 1 cm-sized tumors from the 4T1 cell line. Mice were sacrificed three days post-implantation. Tumors were harvested for IHC.
Biomarkers for immune cell infiltration (Ly6G and F480) were applied on tumor tissues in a 1:300 and 1:500 dilution, respectively. Staining with DAB and Hematoxylin was performed to image and characterize drug activity.
The dual-loaded thread induced necrosis, whereas non-threaded tumors (control) remained healthy. The brown pigmentation in the right image reflects increased immune cell infiltration to the tumor site. You can also see holes on the right image, which represents dead tumor cells.
The thread can dually capture anti-PD-L1 and CXCL9 molecules (The loaded thread induced macrophage infiltration and increased tumor cell apoptosis The novel biomaterial Nylon 6,6 functionalized with Cibacron blue is an effective vehicle for targeted drug delivery Future directions include further proteomic characterization of thread-induced immune infiltration, quantification of immune infiltration, and confirmation of CXCL9 chemotactic abilities after release from thread

College of Engineering and Computing OSCAR Undergraduate Research Scholars Program (URSP) - OSCAR

Enhancing Steel Design Learning by Demonstrating Failure Modes in Steel Connections using Virtual and 3D Printed Models

Author(s): Omar Abu-Khalifa

Mentor(s): Doaa Bondok, Civil and Infrastructure Engineering

Abstract

In introductory steel design courses, students often work with complex and empirical design formulas that were developed through intensive research and were verified through observation rather than theory. Students often struggle with applying these design equations and need more visuals and illustrations to comprehend and use these formulas correctly. This research aims to investigate and propose methods to enhance the understanding of steel design concepts. These methods include 3D-printed connection models and creating illustrative interactive models to visualize concepts like buckling modes and block shear failure in tension members.

Audio Transcript

Hello everyone, my name is Omar Abu-Khalifa. I am a Civil Engineering major in my senior year of University and I’m here today to talk about Enhancing Steel Design Learning by Demonstrating Failure Modes in Steel Connections using Virtual and 3D Printed Models. To get started I want to first give a bit of an introduction to what my research project is focused on. Essentially, in introductory steel design courses, students often work with complex, empirical design formulas. Students often struggle with applying these design equations and need more visuals and illustrations to comprehend and use these formulas correctly. This research aims to investigate methods to improve student understanding of steel design concepts. These methods include developing 3D-printed connection models and creating an illustrative interactive model to visualize concepts likebuckling modes and block shear failure in tension members. Now, what were the goals of the research? When starting this research my mentor and I wanted us to print 3-D models of Steel Connections that demonstrate common failure modes, explore an illustrative interactive model that prospers student engagement similar to the model in figure 2, which was provided by AISC model viewer, demonstrates the failure modes for a double angle brace connection. The model shows tensile and block shear rupture failure. As research progressed, we shifted our goals to explore the implementation of Augmented Reality and Virtuality Reality softwares in education. This goal was based on reading I did over the summer when researching ideas. Now that the research goals have been discussed, let’s talk about the methodology. The first thing I did was conduct a thorough literature review. When conducting the literature review, I read articles that talked about utilizing lab spaces to study the failure in steel beams, conducting site visits so that students can see and visualize steel beams, having the professor use prerecorded lectures, among other things. The next step for me was to go to the MIX to get training in 3-D printing and exposure to 3-D printing. After getting exposure, I modeled standard steel beam-column and moment connections on AutoCAD and printed them. Look at figure 2 to see an example of a beam column connection. After printing, I explored the AISC interactive model viewer as seen in figure 2 and 3. Reflecting back on the research, I recognize that there are many more methods that could be done instead of 3-D printing models and using the interactive model viewer such as utilizing labs and conducting site visits but GMU resources do not allow for this, and planning the logistic behind this makes it more complicated. In addition, more research needs to be done on implementing AR and VR softwares in an education setting. In the future, this research can be expanded by evaluating the effectiveness of the teaching aids, further explore AR and VR softwares, and to continue working on the modeler. I’d like to acknowledge OSCAR, the Civil Engineering Department, AISC, Dr. Bondok and Dr. Lee. Thank you all for your time.

College of Engineering and Computing OSCAR

Relationship Between Eye movement and Eye Muscle on Ultrasound

Author(s): Andrew J Ryan, Zeinab Elahy

Mentor(s): Qi Wei, Bioengineering

Abstract

The advancement of bioimaging technologies has significantly progressed in recent years, which can be used to image many parts of the body. However, despite these developments, the human eye remains relatively understudied in dynamic imaging. By utilizing ultrasound imaging, we can learn more about the movement of the eye muscles while the eye is moving, particularly the medial rectus muscle (MRM). This can provide new avenues for diagnostic capabilities. The purpose of this study was to analyze the relationship between eye movement and the MRM echo-intesnity (echo-texture) on ultrasound. We hypothesized that there is a periodic relationship between eye movement and muscle echo-texture. In this study, we utilized eye data from multiple subjects. Our team obtained IRB approval to obtain images, with all participants providing consent before enrolling in the imaging study. The participants were asks to move their gaze from left to right and vice versa, following a target. This gave us series of image stacks, containing an average of 220 frames. Using MATLAB App Designer, we created an application that can load image stacks of ultrasound; shade in, annotate, and trace the MRM; and save the tracings as a MATLAB cell struct file. That file was then subsequently processed in another code, using MATLAB regionprops function, to produce a figure that quantifies the muscle echo-intensity (tracings) over gaze (frames). The results suggested that there is a periodic relationship between MRM echo intensity and eye movement. More data must be collected to acquire a more accurate interpretation.

Audio Transcript

Hello everyone, I’m Zeinab and my URSP research was analyzing the relationship between eye movement and extrocular muscle movement on ultrasound images. This was in collaboration with the Bioengineering Department at George Mason.

So extrocular muscles are just a fancy word for eye muscles. The eye muscles we focused on for this research was this muscle, the medial rectus muscle. And it’s the muscle that is closest to the nose on both eyes. So this right here is the right eye. Here we have, this would be the nose and this muscle is basically in charge of moving this eye toward the nose.
So it’s in charge of moving the right eye to the left and on the opposite side same thing.
It’s in charge of moving the left eye to the right. And any problems with this muscle could result in double vision or being cross-side. So how would a doctor and eye doctor examine that or examine the eyes in general?

Well there are different methods to take images of the eye, there’s retinal imaging, which is probably the one most people have had taken before. That provides information on the optic nerves and your vision. In serious cases, the doctor might want to look at the bone structure or muscles in the surrounding areas of the eyes. And that’s when they would use X-ray or CT or MRI imaging. These are all very innovative, but the problem is they provide still images. What if we want to somehow image or compile a video of the eye while the eye is moving or look at it in real time?

That’s when we turn the ultrasound imaging. A clinician or a technician will run a small probe on your eyelid or under the eyelid. The patient might keep their eye closed or open depending on the procedure. And that will get you this image right here. Ocular ultrasound imaging is used a lot. It can be used to find foreign bodies such as tumors and blood pooling and to evaluate any trauma in the eye, evaluate the optic nerve, any lens detachments. However, there are no studies on evaluating how the muscle changes.
And we can only see that change when the eye is moving. So that’s the topic we wanted to research.

What is the relationship between eye movement and the medial rectus muscle’s echo intensity? And by echo intensity, I mean the ultrasound image pixel intensity of the muscle,
which can kind of quantify as the general shape of it.

For my research, we conducted ocular ultrasound on multiple participants,
multiple trials. In order to process those movements and segment that muscle intensity,
we used MATLAB app designer to trace the MRM on each ultrasound session, tracing every 5 to 10 frames. And then we used MATLAB to convert those tracing into a figure and quantify the results.

All right, so first we have one example of an ultrasound image stack that we took. This is the right eye. And here’s the pupil area right here. So we asked the participant to move their eye left and right while looking at a target. I know it looks like it’s going up and down,
but that’s just because of the position of the probe. And down here is the medial rectus muscle. And as you can see, you can already see the muscle changing. The echo intensity and the shape is changing while the participant is moving their eye left and right.

And just the screen recording of how I did this,as you can see, I have the image stacks loaded here on the MATLAB app. There are 224 frames in this one. I can move them around and I traced every 5 frames or so. And to demonstrate right here is the medial rectus muscle. And so I traced right around that outline. I normally do this zoomed in, but for demonstration purposes, I zoomed out. And then I would go to the next frame. Again, normally I would do it every 5 to 10 frames, but I’ll just trace this one right here. And then after that, I would save the annotations of all the traced muscles
as a MATLAB cell-struct file.

All right, so after processing that, here is one of the ultrasound sessions. And this is the figure that we were able to generate. The y-axis is the muscle intensity while the x-axis is the frame. And again, we can correspond frame with time or as the muscle, as the eye moves. Excuse me. And so these blue dots are representatives of the tracings that I did
and this red line is the periodic regression that we fitted it with. And to kind of illustrate that right here, you can see the beginning frames, the beginning segments that I did. They’re kind of similar. So the muscle was hardly moving, which means the eye was probably not moving. And so if I press play right here, we can see that is true. Okay, right now for those first few seconds, the eye was not moving. So we can say up to frame 60, 50 or so. The eye wasn’t moving and so the muscle wasn’t moving. The muscle wasn’t changing. You could see the shaded areas that I would do were probably not, not too different from each other.
And so right now, the eye moves to the left. It moves to leftmost and this is probably where the leftmost is. And so the muscle echo intensity, you can see here it’s a lot smaller. It’s almost really thin. That means the echo intensity was going down, which again is shown here. That makes sense. So much so that right here, when the eye just changes direction,
so probably around 80, right here. Around frame 80, the eye starts to change direction. And so the muscle is getting bigger as the eye is moving to the right. And that again makes sense. The eye moves to the right, the muscle echo intensity just gets bigger and bigger. Up until this peak right here, again, the eye changes direction and starts to move to the left. And we have that cycle again, comes back now. And again, notice the muscle echo intensity is very big and then it starts to get small again. So we can conclude that at every peak, that’s represented at the eye changing direction because the muscle changes shape.
And so we can say that there is a relationship between gaze and muscle echo intensity. These results suggest it. They don’t necessarily say it, but they suggest it.

Now, there were some limitations to these methods. First off, it was very time consuming.
Tracing every 10 frames took about 10 minutes. Tracing every be 5 frames took longer, about 15, 20 minutes. Now, that doesn’t seem long, but every participant conducted 6 trials. So compiling all the tracings were just one participant takes anywhere between an hour to an hour and a half. Another limitation was that some of these images of the eyes
were bit unclear, which made me not trace it at all sometimes. So if you can see in this image right here, there’s a giant gap between these two frames. I didn’t take any images here or any tracings here because it was just hard to see on the ultrasound. And so that created this giant decrease in the regression. And that would not create some accurate results. Another thing was that there were some problems with the coding and the apps.
And so we spent a lot of time troubleshooting and debugging. And finally, the results were very promising. However, we would need more participants, more data in order to reach a better conclusion.

And so our next steps would be to gather more data from more participants. And then again, because tracing is time consuming, we would want to look into possibly making the tracing process automatic using machine learning processes. And then we can analyze how the maximum muscle thickness changes as the eye moves as well. And for long term, we can examine the same relationship with the other five extracurricular muscles.

All right, so to conclude, again, we found a periodic relationship between the MRM and gaze. In general, ultrasound is a very useful imaging technology. This type of research is very novel and innovative. Research on the eye and eye movement, though fairly understudied, has a promising future with these types of developments. And special thanks to OSCARS for their URSP funding, our participants of the study, the Department of Bioengineering, especially Dr. Wei and the Biomechanics Lab. Thank you very much for watching.

College of Engineering and Computing

Septic Systems to Climate Change: A Systematic Review of Microbial Processes Under Precipitation, Drought, and Temperature Stress

Author(s): Abdalla Abdalla, Allan Justine Rowley, Yasmine El Messary

Mentor(s): Kirin Emlet Furst, Civil Engineering

Abstract

Septic tank (ST) systems are a cost-effective form of decentralized sanitation widely used globally to manage wastewater. However, these systems face growing challenges from climate change stressors, including extreme precipitation, rising temperatures, and droughts, which can significantly impact their performance and environmental safety. Despite their importance, limited research explores how these stressors influence septic system functionality and risks to groundwater quality and public health. This review assesses the current literature on the effects of precipitation, temperature, and drought on septic system performance, identifying key contaminants and factors contributing to system failure.

A systematic review of studies from three databases (PubMed, Web of Science, and Scopus) identified 50 peer-reviewed articles meeting inclusion criteria. Findings revealed that precipitation causes hydraulic overloading, groundwater infiltration, and physical damage to soil treatment units. High temperatures accelerate microbial digestion, increasing nutrient and solid discharges. Drought exacerbates clogging and reduces soil filtration efficiency. Contaminants identified included nitrate, phosphorus, E. coli, total coliforms, and emerging pollutants like pharmaceuticals and PFAS, with significant research gaps in low- and middle-income regions.

This review underscores the need for climate-adaptive management practices, including integrating green infrastructure for runoff control, advanced treatment units to enhance nutrient removal, and policies promoting regular system maintenance. Addressing vulnerabilities in septic systems is critical to mitigating contamination risks, protecting groundwater resources, and supporting public health. Further research on emerging contaminants and regional differences is essential for sustainable wastewater management in a changing climate.

Audio Transcript

Did you know that nearly one-forth of the world wastewater comes from septic systems but only 48% adequately treat wastewater. These systems rely on soil for natural filtration, making them vulnerable to environmental changes. My research focuses on how climate change stressors-like rain, drought, temperature – affect septic systems and the gaps in our understanding of these impacts.
Septic systems are critical for wastewater management, but they face challenges under climate change. For instance, increased rainfall can overwhelm systems, while droughts can disrupt soil filtration. Despite these risks, limited research exists on climate variables influence septic systems functionality. My goal is to address this gap by reviewing peer-reviewed literature to understand these impacts.
To identify relevant studies, I conducted systematic searches across PubMed, Scopus and Web of Science. I used specific keyword strings like climate change”, septic systems”, and precipitation” to retrieve data. For example, one search on PubMed yielded 226 results, while Scopus returned 1840. Across all searches and databases, I identified 196 unique articles after removing duplicates. These were screened based on relevance, language and focus on septic systems affects by climate stressors. The screening process included title, abstract and full- text reviews, which narrows down the pool to 50 for detailed analysis.
In conclusion, septic systems are vital yet vulnerable infrastructure. By understanding how climate change impacts them, we can better adapt to future challenges. To learn more about my findings or discuss collaboration opportunities, please feel free to reach out. Thank you!

College of Visual and Performing Arts Honors College

spider – EP

Author(s): Leigh Eggleston

Mentor(s): Jesse Guessford, Music Technology

Abstract

“spider – EP” is a series of four songs drawing from the breakcore, harsh noise, modern jazz, and early 20th century classical styles. I wrote “spider” to encapsulate some of my experiences with hallucinations induced by a schizoaffective disorder- both positive and negative- as well as the feeling of not being taken seriously or stereotyped because of my identity when I try to explain my experiences to others. In this video, I will show short demos of each track that are most effective at conveying their respective messages. The recurring use of bitcrush filters represents the need to filter my thoughts into words that cannot fully encapsulate my experiences when I talk about psychosis, and the heavy inclusion of breakcore elements throughout the EP is symbolic of the stereotyping I receive.

The first track, “spider,” evokes the tiny, fleeting hallucinations that I experience on a near-daily basis.

The second, “hooded,” is reminiscent of a particular time I hallucinated that someone was chasing me down the sidewalk at night.

The third, “gunplay,” is an auditory recreation of my sudden recollection of a particularly disturbing image, and a subsequent, even more disturbing hallucination.

The fourth and final, “horizon,” is meant to evoke the feelings caused by my more profound, grounding, and sometimes heartening hallucinations.

Enjoy.

Audio Transcript

This project is purely instrumental, with extremely limited visuals.

College of Engineering and Computing Honors College OSCAR

Technology of Tomorrow

Author(s): Alexia De Costa

Mentor(s): Kasey Thomas, University Life

Abstract

This project merges art and technology through an interactive installation that showcases innovations from the Mason Autonomy and Robotics Center (MARC), including ground robots and computer vision. Created through interdisciplinary collaboration, the collection explores the relationship between creativity and technological progress. The first piece, Trailblazers, features ground robots navigating a maze of hedges that resemble the George Mason University logo, while The Digital Mirror reinterprets René Magritte’s The False Mirror to explore computer vision and machine perception. These immersive artworks invite viewers to engage with technology in accessible, thought-provoking ways to foster a deeper connection between people and the technology shaping our future.

Audio Transcript

Art and technology have traditionally been viewed as separate domains, but my project bridges these two areas through the creation of an interactive art installation. This installation showcases some of the remarkable innovations developed at the Mason Autonomy and Robotics Center (MARC), where cutting-edge technology like blimps, ground robots, computer vision, artificial intelligence, and advanced algorithms come to life. By integrating these elements into art, the project aims to highlight the interplay between creativity and technological progress, fostering a deeper appreciation and understanding of both.
The collection itself was developed with the help of students from diverse academic backgrounds. Our collective effort brings together expertise in robotics, computer science, engineering, and the arts, emphasizing the power of interdisciplinary collaboration in creating innovative experiences.
The first piece in the collection, Trailblazers, focuses on the ground robots developed at MARC and their interactions with their surroundings. This artwork features a maze of hedges inspired by George Mason University’s logo, symbolizing innovation and growth. The robots in this piece are equipped with LED-lit spheres that diffuse light, creating a visually captivating effect.
The panels of the piece were laser-cut to accommodate the embedded LEDs. As viewers approach, an ultrasonic sensor detects their movement, activating lights that trace a path through the maze. This interaction mirrors how the ground robots navigate and adapt to changes in their environment. By blending technical precision with artistic design, Trailblazers provides a dynamic sensory experience that showcases the advanced robotics research at MARC and how robots can engage with physical spaces in meaningful ways.
The second piece, The Digital Mirror, offers a contemporary reinterpretation of René Magritte’s The False Mirror which is a surrealist painting depicting a solitary eye reflecting a cloud-filled sky. In this piece, the eye is animated with a servo, camera, and linear actuator, allowing it to move left and right as it follows certain colors in its surroundings.
At the heart of this piece is an exploration of computer vision. The pixelated image within the iris represents how computer vision interprets the world in discrete pixels, while the more detailed background symbolizes the richness and complexity of real-world conditions. This contrast between clarity and abstraction reveals both the imperfections and the incredible potential of computer vision technology. Through its design, The Digital Mirror invites viewers to reflect on how machines perceive the world and the challenges of bridging the gap between digital interpretation and human experience.
These artworks go beyond static displays, they are immersive, interactive experiences that engage audiences on multiple levels. By integrating technology into art, the pieces invite viewers to explore the possibilities of robotics and computer vision in ways that are accessible and thought-provoking. This fusion of creativity and innovation not only highlights the groundbreaking work at MARC but also opens the door for wider conversations about how technology can shape our future.
Through pieces like Trailblazers and The Digital Mirror, this project aims to inspire curiosity and foster a deeper connection between people and the technologies transforming our world.
I would like to express my sincere gratitude to my mentor, Ms. Kasey Thomas, for her invaluable guidance. I am also thankful to Dr. Missy Cummings for her continued support of this project through the MARC. My heartfelt thanks go to the team of students who contributed, and to Dr. Lee, without whom this project would not have been possible. Thank you.

College of Science Honors College OSCAR

The Effect of Ethylene Glycol on Homomeric α1 Glycine Receptor Function in Xenopus Laevis Oocytes

Author(s): Fae Jensen

Mentor(s): Greta Ann Herin, Neuroscience

Abstract

Ethylene glycol is a common environmental contaminant, as it is a primary component of the solution used in fracking. It remains in the soil and groundwater of fracking sites, therefore causing it to have a sustained effect on both human and other biological life in these areas. Ingestion of ethylene glycol inhibits central nervous system (CNS) functioning, though the specific neuronal mechanisms of this depression are currently unknown. To address this gap in knowledge, this project seeks to determine if ethylene glycol modulates glycine receptor function in a concentration dependent manner. This will be done by microinjecting Xenopus Laevis oocytes with RNA of the α1 subunit of glycine receptors (GlyRα1). Once the receptors are expressed, Two Electrode Voltage Clamp (TEVC) electrophysiology will be used to record transmembrane current caused by Cl- influx through the ion channel pore of the receptors. As GlyRs are one of the primary inhibitory neurotransmitter receptors of the CNS, these recordings will potentially identify a method by which CNS functioning is modulated by ethylene glycol.

Audio Transcript

Hello! I’m Fae Jensen and I am currently studying the effects of ethylene glycol on glycine receptors of the alpha1 subtype in Xenopus Laevis oocytes and I’m doing this in Dr. Herin’s lab.

The purpose of my experiment is to determine the effects of ethylene glycol on homomeric α1 glycine receptors expressed in Xenopus oocytes and whether these effects occur in a concentration-dependent manner.

Ethylene glycol is a widespread environmental contaminant due to its use in fracking solution. When ingested, it functions as a CNS depressant, though the mechanisms of this depression are currently unknown. Because of this, I’m studying its effects on glycine receptors. This is because when glycine binds to the two binding domains on glycine receptors it causes a conformational change in the receptor which allows the ion channel pore to open, thereby allowing Cl- ion influx into the cell. This Cl- influx brings a negative charge along with it, which can have a hyperpolarizing effect on the cell and overall causes a decreased likelihood for action potential generation, thereby causing CNS depression.

In order to do this I’m using Xenopus Laevis oocytes which are the preferred model system for the study of receptor and ion channel physiology due to their size and membrane durability.

My hypothesis is that Cl- influx through the ion channel pore will increase in a concentration-dependent manner upon exposure to ethylene glycol. I propose this will be the case because ethylene glycol and ethanol have a very similar chemical structure, as you can see here, and I believe this will therefore cause ethylene glycol to bind to the same domain on glycine receptors as does ethanol. And because ethanol is known to allosterically increase glycine receptor response when it binds to this domain.

In order to conduct my experiments, I first start out by checking my cDNA samples for quality assurance. I then replicate the DNA sample if need be, and then transcribe it into mRNA so that it can be translated into proteins once injected into the cytoplasm of cells.
Following this process, I then very controlledly inject 0.05 μL of GlyRα1 RNA into each Xenopus laevis oocyte. I allow the oocytes to incubate for 1-3 days to allow for GlyRα1 proteins to be expressed on the membrane.
I then record from the each oocyte using Two Electrode Voltage Clamping. By clamping this voltage, I am then able to record the actual ion currents which are flowing across the membrane through glycine receptors and other ion channels.

While recording I first begin by perfusing plain ND96 over my cell in order to obtain a baseline recording. I then perfuse my cells with 1 mL of each of my experimental solutions, washing the cell out with ND96 between each solution. This is completed in a randomized order and for sets of solutions consisting of a fixed amount of glycine and varied concentrations of ethylene glycol, as well as for solutions consisting of a set amount of ethylene glycol and varied concentrations of glycine. This allows me to observe how ethylene glycol modulates glycine receptor function in real time, as well as determine whether glycine receptors respond normally to increased concentrations of glycine when exposed to ethylene glycol.

Here are the results from my recordings studying the glycine receptor’s response to various concentrations of glycine while in the presence of 300 uM of ethylene glycol, with the concentration of glycine along the x-axis and the average normalized current from five cells on the y-axis.

And here is my concentration response curve for ethylene glycol recorded across five cells. All of these recordings were taken from cells from the same frog so endogenous ion channel expression may affect these results, but as of yet it is looking like ethylene glycol may in fact potentiate the glycinergic current at concentrations of 300 uM and higher.

Here are my references.

So, finally I would like to give a big thanks to Dr. Herin for her continuous support and mentorship throughout this project, and I would like to thank the OSCAR program for providing me funding in the form of URSP grants. Thank you!!

College of Humanities and Social Science OSCAR

The Effect of Ionotropic and Non-ionotropic NMDAR Signaling Domains on Postnatal Development of LTD Using Chimeric GluN2 Mice

Author(s): Bryce Sullivan

Mentor(s): Theodore Dumas, Neuroscience

Abstract

The hippocampus, which is a brain region essential for information processing, learning, and memory formation, undergoes critical periods of heightened experience-dependent changes to neuronal structure and function (plasticity). N-methyl-D-aspartate receptors (NMDARs) are necessary for this process in excitatory hippocampal synapses through synaptic strenghening (long-term potentiation, LTP) and weakening (long-term depression, LTD). NMDARs have been shown to behave both ionotropically and nonionotropically, and that specific domains on the GluN2A and GluN2B subunits contribute to synaptic plasticity. In mice, the third postnatal week (~three years old in humans) marks the onset of mature learning and memory and is the result of a shift of dominance from GluN2B to GluN2A subunits. In this project, the impact of individual NMDAR GluN2 subunits signaling streams on the hippocampal development of LTD. This was done using chimeric that contain either GluN2A or GluN2B with the carboxy terminal domains (CTDs) swapped (i.e. Glu2A-BCTD and GluN2B-ACTD), which allows isolation of the ionotropic and nonionotropic signaling properties of each GluN2 subunit. A 1 Hz stimulation was used for 15 minutes to induce LTD in CA1 of hippocampal slices of these chimeric constructs and wild-type (WT) and the field excitatory post-synaptic potentials (fEPSPs) were recorded. While more data needs to be collected and analyzed, these experiments will provide a better understanding of how ionotropic and nonionotropic NMDAR signaling domains regulate the late postnatal development of LTD.

Audio Transcript

Hello everyone! My name is Bryce Sullivan, and my projected is looking at the effect of ionotropic and non-ionotropic NMDAR Signaling Domains on Postnatal Development of LTD Using Chimeric GluN2 Mice

The hippocampus, named after its seahorse-like shape in humans, is an essential brain structure for spatial learning and memory in adults. Development of the hippocampus occurs in the late postnatal period and coincides with the emergence of adult-like spatial learning and memory abilities at around three years of age in humans, or three weeks of age in rodents.

Synapses are the electrochemical junctions between neurons that allow for neural circuits to be built and to process information. The ability of excitatory synapses in the hippocampus to alter their function with new experiences and create neural substrates of memories is referred to as synaptic plasticity.” The final maturation process of the hippocampus involves modifications in synaptic plasticity.

In our lab, we study the NMDA receptor, NMDARs, which are essential for activity-dependent plasticity at excitatory synapses. The prominent forms of synaptic plasticity induced by NMDAR activation are long-term potentiation, LTP, and long-term depression, LTD. So, when a synapse is activated at high frequencies, NMDARs respond by sending signals to strengthen that synapse, which is LTP. However, when a synapse is activated at lower frequencies, NMDARs send a signal to weaken that synapse, which is LTD.

NMDARs are ion channels that allow calcium to enter the activated cell. It is well known that calcium activates synaptic plasticity processes. However, in 2013, it was discovered that NMDARs produce signals that are not related to calcium, that are mediated by the intracellular portion of the NMDAR subunits.

To study separate influences of calcium-dependent and calcium-independent signals, our lab created chimeric NMDAR subunits. I am using mice that express chimeric NMDAR subunits to investigate which NMDAR signaling pathways underlie the development of LTD. My electrophysiological recordings take place on postnatal day (or P) 17 to 19 and P22 to 24. These two age groups represent the immature hippocampus (younger than three postnatal weeks) and the mature hippocampus (older than three postnatal weeks).

My project’s primary three methodologies consist of genotyping, hippocampal slice prep, and hippocampal slice recordings of field excitatory post-synaptic potentials (fEPSPs) in CA1. Genotyping consists of taking small tail snips of our mice, DNA precipitation to isolate a DNA sample from that tail, running a polymerase chain reaction (or PCR) to isolate and amplify our chimera genes (if present), and then running a gel electrophoresis to find their genotype.

Hippocampal slice preparation is as it sounds; sacrificing the mouse, dissecting and isolating the hippocampus, and cutting the hippocampus into slices that are about a half a millimeter thick. These slices can be maintained alive in a recording chamber for many hours.

To record from hippocampal slices, we use two electrodes as this sample image (A) shows here. The bipolar electrode here is a platinum-iridium wire that activates the input neurons that project to area CA1. Synaptic responses are recorded in area CA1. The waveform in B represents an excitatory synaptic potential. The dotted line shows how we measure the slope of this response.

When LTP is induced, the EPSP gets larger. When LTD is induced, the EPSP gets smaller. For our LTD protocol, we use a 1Hz stimulation for 15 minutes.

It is well known that low frequency stimulation elicits LTD to a greater extent in immature mice. However it is not known if this reduction in LTD with increasing age is due to changes in calcium-dependent or calcium-independent NMDAR signaling. Performing LTD experiments in mice that express chimeric NMDAR subunits allows for testing of these two different possibilities.

I would finally like to thank OSCAR for providing me funding for my project with the URSP program and Dr. Dumas along with the rest of the PBNJ lab for their support and mentorship. This is not the present PBNJ lab, but I felt as though this photo from before 2015 was appropriate

And here are my references

College of Visual and Performing Arts

The Evolution of Mario Music

Author(s): Jessica Taylor

Mentor(s): Jesse Guessford, Music Technology

Abstract

My research will explore how the musical style of Nintendo’s mainline 2D and 3D Mario series has evolved overtime.
I will specifically focus on four games: Super Mario Bros. (1985), Super Mario Bros. Wonder (2023), Super Mario 64 (1996), and Super Mario Galaxy 2 (2010). The first two are 2D, side-scrolling platformers, and the last two are 3D, open-world puzzle platformer games.
Super Mario games include different areas” that share visual and musical elements to build an immersive atmosphere. I will focus on certain area themes” from the selected games: the overworld theme, the underwater theme, and the castle theme.
The themes will be compared through the lens of instrumentation, form, rhythm, and reuse”. Reuse refers to recurring melodic ideas, rearrangements, and how the song connects to the idea of Mario music as a whole. Comparing these elements in the selected Mario themes will allow for the exploration of how Mario music has evolved into what it is today.

Audio Transcript

hi my name is Jessica Taylor and I am a senior in the music Technology Program here at George Mason and I did My Capstone research project on the evolution of Mario music this platforming video game series has been close to my heart ever since I was a kid and I enjoy the depth and versatility that comes in the music of such a long running and diverse Series so I wanted to look into that this is my thesis just state it more properly exploring how the musical style of Nintendo’s Mainline 2D and 3D Mario Series has evolved over time and for each game I picked an Overworld theme an underwater theme and a castle theme because there are certain elements that make these themes what they are make them immersive make them associate with these areas that they’re trying to convey to The Listener such as their instrumentation their form or maybe some recurring melodic ideas or rearrangements throughout the series um so I know that’s a lot of lenses I’ll be looking at things through but I’m going to for the interest of time go through the Overworld theme from the first and second game that I analyzed which is actually the oldest Mario game and then the most recent one that came out in 2023 Super Mario Bros Wonder um I will be analyzing the Overworld themes from them so this is the Super Mario Bros Overworld theme I will play a little

excerpt so as you you can see the instrumentation is very simple that’s due to technological limitations at the time but the composer koi condo did the best he could to make an upbeat interesting sounding piece um the form is ABC and Mario music is often very AB ABC form Reliant it’s got a lot of periodic structure um and that little intro Hook is one of the most iconic Mario music figures probably of all time and what I noticed during this project is that there are little intro hooks in a lot of Mario pieces whether it be a castle theme or an underwater theme there is something that gets the listener into the piece and then there is the actual atmosphere um and then this song has been rearranged 30 times throughout the uh just the mainline Super Mario series which I find really interesting everyone kind of knows this song If you know any Mario song you would know this one this is the newest Overworld theme from the newest game

so obviously the instrumentation is a lot more broad it’s acoustic it’s live it’s very well recorded it brings a lot of energy but both of these pieces have that upbeat Happy Feeling where Mario is adventurous and he’s saving the day and you can just tell he’s good from this um and something once again the form is AB in terms of reuse like elements that I find in a lot of Overworld themes the hook we’ve got the kind of similar to the um it kind of plays on that a little bit um and the harmony it’s very major major key in chords the melody is very focused on these main chord tones with little bits of added chromaticism here and there to give it a playful feeling and then the rhythm is very syncopated which is also one of the things that makes the original theme stick out a lot so that helps give it that um Groove and upbeat Vibe so that’s just two of the examples that I looked at over my research but across all the games and all the songs that I looked at I found that what stuck out to me as defining Mario music as a whole were three things fun drama and catchiness so by fun I mean it’s upbeat it’s easy to listen to there’s a lot of major Harmony there’s syncopation to make it groovy but there’s also drama you know there’s scary moments in these games or more deep and meaningful moments in the games that have more story um and this is backed up by chromaticism modal mixture to create a darker tone unique rhythms that allow Melodies to be weirder but still digestible to The Listener and then finally catchiness so so many songs have hooks I think literally just me singing D D D D D is enough proof that catchiness and hooks are an integral part of Mario music um there’s a lot of repetition whether that being the melody or whether it’s literally rearranging a song for a later game um there’s a lot of rearrangements and reuse in the Mario Series so these are the things that I found Define Mario music thank you and these are my sources

College of Engineering and Computing OSCAR

Using AI to Quantitatively Analyze Extraocular Muscle Pulley Morphology from MRI

Author(s): Jahayra Guzman-Rivas

Mentor(s): Qi Wei, Bioengineering

Abstract

Strabismus is the misalignment of the eyes, which can be caused by abnormalities in the pulley connective tissues. Magnetic Resonance Imaging (MRI) is used to study the structural and biomechanical features of strabismus. Recently, artificial intelligence (AI) techniques, specifically deep learning, have been implemented in segmenting the images obtained by MRI. However, these techniques need improvements for more accurate depictions of the structures. MRI images from patients with strabismus containing the extraocular muscle pulley morphology were obtained. Deep learning techniques will be used to locate the muscles using pixel-based labeling. Then, segmentation masks will be created containing the muscles with various colors. These locations will be analyzed through two F-measure-based metrics. These metrics are the Intersection of Union (IoU) and the Dice coefficient. While results have not yet been determined, the techniques are expected to accurately show the location of each extraocular muscle through different colors representing each muscle. These techniques are also expected to obtain IoU and Dice scores of close to 1 to show a complete overlap between the original MRI image and the image of the predicted locations. These refinements in the segmentation process will significantly enhance the performance of AI segmentation used for studying strabismus in medical imaging.

Audio Transcript

Hello everyone. My name is Jahayra Guzman-Rivas, and I am a bioengineering student at George Mason University. Today, I will be talking about my research in using artificial intelligence to quantitatively analyze the extraocular pulley morphology from MRI.

It is important to first understand Strabismus for this research project. Strabismus is the misalignment of the eyes. This condition occurs in 0.5 to 5 percent of the global population. Strabismus can be caused by abnormalities in any of the six extraocular muscles and their pulley systems. These five muscles are the medial rectus, lateral rectus, inferior rectus, superior rectus, and superior oblique.

When strabismus is examined in patients, magnetic resonance imaging, or MRI, has been implemented in the clinical spaces as it looks at the neuro-biomechanical factors of eye movements.

However, there are limitations to the use of MRI. When clinicians and trained experts segment the extraocular muscles and other ocular structures manually, it can be very time-consuming and labor-intensive.

In recent years, a specific field of study in Artificial Intelligence, specifically deep learning, has been applied to the process of segmenting the muscles in the eyes. Deep learning is a method in AI that instructs computers how to process data using neural networks. However, these techniques must be improved.

My research involves using deep learning methods to locate extraocular muscles using pixel-based labeling. I will be using MATLAB to implement deep learning methods. I will also use data collected from 13 patients. This data was collected at UCLA and intended for research purposes only.

Before I started using the deep learning methods, I conducted extensive literature reviews to further understand the anatomy of the eye and the utilization of deep learning methods.

I also confirmed which data is available and noted them in a summary sheet.

After noting the available data, I started preparing them for the deep learning methods. I looked at the images for each slice of each muscle for each eye for each patient and renamed them according to their slice and muscle using ImageJ. I then compiled all the slices of all the muscles of each eye of each patient in one folder. This process took about one month as I had 13 patients and 1,662 images to look at.

Since the code I obtained to create the masks required the slices for each eye for each patient to have a different naming format, I had to create new code in MATLAB that organized them into the right format. This took me about a week to complete.

I then used these stacks of images to create masks of the five muscles and have them shown in various colors.

As for the next steps, I must implement them into the deep learning model to train it with masks for each patient for each eye, validate the model, test the model, and adjust the model as needed.

While I made a lot of progress on my project, I could not complete it within this semester. However, I was able to gain a lot from this experience. For example, I was able to enhance my coding skills with MATLAB. Additionally, I gained a better understanding of deep learning algorithms and their implementation in segmentation. I also learned that preprocessing the data before implementing the deep learning methods are critical to the model’s training process.

I want to express many thanks to Dr. Lee and the George Mason University Office of Student Creative Activities and Research as they helped fund this research through the Undergraduate Research Scholars Program. I also want to thank my mentor, Dr. Wei, for guiding me throughout this process. I want to acknowledge Amad Quereshi for guiding me and providing the code needed for my research.

Thank you!

College of Visual and Performing Arts

Algorithmic Reverb Through History

Author(s): Gage Jones

Mentor(s): Jesse Guessford, College of Visual and Performing Arts

Abstract

This project explores the recreation of three influential algorithmic reverbs using PlugData, a Pure Data-based interpreter integrated with JUCE, a robust C++ framework for digital signal processing. By reconstructing these iconic algorithms, the study investigates their sound and historical significance in shaping modern reverb designs. This work provides insight into the evolution of algorithmic reverbs and their influence on contemporary audio processing practices.

Audio Transcript

Hello, my name is Gage Jones and I’m here to report my findings on algorithmic reverbs through history. Algorithmic reverb are reverbs that mimic a space by a mathematical equation and they could be in real or non real spaces and it’s incredibly controllable. A famous example is a Lexicon 224 which is heard in many famous recordings from the late 70s and early 80s. Different examples of algorithms. First is the algorithm by Manfred Schroeder that started it all, and it sounds like a plate reverb due to its diffuse reverb, tail and diffuse means it’s equal over space and time. It also has no early reflections, so it has a particular sound that really sticks out compared to modern reverbs. So to start off with. I want to show a dry signal, then the Schroder reverb signal. So here’s an example of the dry signal. And here is an example with the Schroder Reverb. So as you can tell it is reverb, but it’s also very glassy and has a very particular phonic to it. So James Moore basically took Schroder’s idea and added a couple of things. He added early reflections he adds early and late reflections being controlled by the same system, and also that the late reverb tail is created by using a network of comb and all pass filters for smoother diffusion. Unlike Schroders Reverb, which just used one of each. Now what does this mean in practice? Well, you’ll notice that that one particular phonic is actually not present in the more reverb due to more smoothing. Lastly, I went for John Dattorro’s reverb, which uses a feedback delay network and also features nonlinear processing which caused a smooth diffusion of reflections. Now what this essentially means for me is I kind of visualize it as a fish tank, so it’s essentially like each reflection is a fish and each time that fish sinks further to the bottom, it gets further away. It’ll take that fish and feed it back up to the top, and then it’ll keep everything that it stored inside of the fish as it transfers it back to the top. So essentially it’s a very rich and it builds very fast into an extremely dense echo. And it also features spatial encoding, which means that each of the reflections are actually localized to wherever they are in the fish tank. If you want to call it that way, and it’s also the algorithm that’s featured in the famous lexicon reverb units, and also still used to this day. I also want to include that all of these examples were created inside of plug data, which is a software that infuses both Max MSP and Pure Data objects inside of JUCE C++ repository. So this is the Schroeder reverb. This is the Moore reverb and this is the Dattorro reverb, so hopefully you found that as cool as I did and thank you for watching.