Biomedical Engineering and Bioengineering Commons^™

Advancing Electrical Stimulation: Full-Head Mri Segmentation For Abnormal Brain Anatomy With Tdcs, Andrew Birnbaum

Dissertations and Theses

Evaluating the effectiveness of transcranial direct current stimulation (tDCS) is essential for guiding its integration into therapeutic and performance-enhancement applications. In our laboratory, we investigate the efficacy of tDCS across multiple experimental models, including both animal and human studies. I have contributed significantly to the execution and analysis of these experiments, which include studies in rats and healthy human participants aimed at evaluating whether electrical stimulation of the motor cortex can enhance motor learning. These studies assess improvements in fine motor performance resulting from tDCS. In stroke patients, I contribute to our investigation of tDCS as a rehabilitative intervention, particularly …

Optimal Tissue Clearing Of Gastric Cancerous Organoids Imaged Via High Resolution Light Sheet Microscopy, Lauren D. Lieu

2025 Fall Honors Capstones Projects - Archive

While the rate of surviving a myocardial infarction has increased in the past 60 years from 60% to 90%, the rate of Americans developing chronic heart disease such as heart failure, arrhythmias, and hypertensive heart disease has risen. This has led to the development of imaging technology such as Light Sheet Microscopy (LSM) and Light Field Microscopy (LFM) to study heart contractility and congenital heart disease via models such as cancerous organoids or Zebrafish. However, LSM and LFM results are highly dependent on the quality of the staining and cleared samples. This study looks to add to the growing field …

Signal Analysis Of Calcium Dynamics In Pancreatic Cells, Abhidha Kunwar

2025 Fall Honors Capstones Projects - Archive

Calcium (Ca²⁺) signaling plays a critical role in insulin secretion from pancreatic βcells. Photo-biomodulation (PBM) of red or near-infrared wavelengths is applied to enhance cellular metabolism and Ca²⁺ activity in pancreatic cells. This study aims to rigorously analyze how PBM influences calcium dynamics in pancreatic cells by applying the Fast Fourier Transform (FFT), converting Ca²⁺ spiking patterns to the frequency domain to determine dominant oscillatory behaviors. Using a calcium-binding fluorophore, Ca²⁺ activity was acquired before and after PBM at 810 nm, processed with a machine learning algorithm, and further analyzed in MATLAB using FFT to assess changes in calcium signal …

Excitation And Polarization Of Isolated Neurons By High-Frequency Sine Waves For Temporal Interference Stimulation, Iurii Semenov, Vitalii Kim, Giedre Silkuniene, Andrei G. Pakhomov

Bioelectrics Publications

The capacity of temporal interference (TI) stimulation to target deep brain regions without affecting nearby surface electrodes remains uncertain. Using artifact-free optical recording, we compare excitation patterns and thresholds in hippocampal neurons stimulated by “pure” and amplitude-modulated sine waves, representing TI waveforms near electrodes and at the target, respectively. We show that pure 2- and 20-kHz sine waves induce repetitive firing at rates that increase up to 60–90 Hz with stronger electric fields. Beyond this limit, action potentials merge into sustained depolarization, resulting in an excitation block. Modulating the sine waves at 20 Hz aligns firing with amplitude “beats” and …

Plasmonic Nanopore Sensing For The Characterization Of Viruses And Biomolecules, Scott Renkes

Bioengineering Dissertations - Archive

The rapid advancement of nanomedicine has enabled increasingly precise nanotherapeutic platforms, including targeted nanoparticles, monoclonal antibodies, and viral gene delivery vectors. As these technologies mature, quality control and analytical characterization have emerged as critical bottlenecks, particularly in systems where functional outcomes depend on one-to-one molecular or particle–biological interactions. Conventional ensemble-averaged techniques obscure heterogeneity that is often central to therapeutic efficacy, safety, and manufacturability. A prominent example is adeno-associated virus (AAV)–based gene therapy, where production yields heterogeneous populations of empty, partially loaded, and fully loaded capsids. Genome fill percentage and integrity directly influence therapeutic efficacy and dosing accuracy, while limited understanding …

Benchmarking Batch-Effect Correction Methods Towards The Construction Of A Triple-Negative Breast Cancer Cell Atlas, Peter Scheible, Amy H. Tang, Jing He, Jiangwen Sun

Computer Science Faculty Publications

Triple-negative breast cancer (TNBC) requires detailed cellular mapping given its aggressive nature, immense tumor heterogeneity and genetic diversity. We integrated 156,794 cells from six scRNA-seq datasets—including tumors, metastases, and cell lines—to build a TNBC scRNA cell atlas, focusing on batch effect mitigation while maintaining biological and molecular details. Preprocessing f ilters noise, normalizes data, and leverages PCA for integration readiness. We utilized scANVI, a semi-supervised tool, to align datasets, preserving TNBC’s complex tumor heterogeneity via marker annotations [1]. UMAPs demonstrate biological clustering in integrated data, contrasted with datasetdriven unintegrated patterns. Assessments verifying effective batch correction. This method aligns with NASA’s …

Rehabilitation In Stroke-Related Flexor Synergy, Shawn J. Dirocco

Theses and Dissertations

Upper extremity abnormal flexor synergy caused by stroke can impair individuals by coupling upper extremity muscles with deltoid activation. Previous studies have shown that reduction in deltoid loading can decrease flexor synergy. Robotic rehabilitation has the ability to allow for reduced deltoid loading while assisting or constraining joints along the arm to increase rehabilitation outcomes. The effects of higher degree of freedom low impedance robotics needs to be tested to learn how various parameters affect flexor synergy in comparison to end point robotics. During the first experiment, we tested 16 chronic stroke patients with flexor synergy problems in 3 tasks. …

Intervertebral Lateral Bending Moment Differences In The Lumbar Spine Of Baseball Pitchers Across Throwing Velocities, Justin Humenay

Theses and Dissertations

Introduction Baseball pitching imposes substantial mechanical demands on the lumbar spine, a crucial link in the kinetic chain responsible for transferring energy from the lower body to the upper extremity. While increased pitch velocity is associated with greater trunk forces the specific intervertebral loading patterns during high-velocity pitching remain unclear. This study investigates differences in lateral bending moments across lumbar spinal segments between collegiate pitchers throwing at high versus low velocities.

Methods Twenty right-handed collegiate pitchers were divided into two groups: high-velocity (n = 10, 90.3 ± 1.6 mph) and low-velocity (n = 10, 81.6 ± 1.1 mph). Motion capture …

Characterization Of Nanoplastic-Induced Exacerbation Of Asthmatic Pathophysiology In A Murine In Vivo Model, Keith Li

Theses and Dissertations

As global plastic production increases, so does the environmental and biological presence of nanoplastics (NPs), raising growing concerns about their potential impact on human health. These particles have been detected in various organs, including the lungs, yet their role in respiratory inflammation remains largely unexplored. Emerging evidence suggests that NP exposure may influence immune responses in the lungs, particularly in individuals with preexisting conditions such as asthma. However, the specific ways in which these particles interact with allergen driven inflammation are still unclear.

In this study, a murine model of allergic airway inflammation was used to investigate how surface modified …

Synthesis And Assessment Of Biobased Acrylated Epoxidized Soybean Oil Resins For Stereolithography 3d Printing Of Microfluidic Devices, Natalie S. Romero Figueroa

College of Graduate Studies: Theses & Dissertations

This research focuses on the development and characterization of a biobased photocurable resin synthesized from soybean oil for use in stereolithography (SLA) 3D printing of microfluidic devices. The study explores a sustainable alternative to petroleum-based resins by performing an acrylation reaction on epoxidized soybean oil (ESO) to produce acrylated epoxidized soybean oil (AESO), which was then formulated into a photocurable resin with the addition of a photo initiator. The fabrication process involved designing microfluidic molds in SolidWorks and printing them using an Elegoo Mars 4 SLA printer under various exposure and layer thickness parameters. The printed samples consisted of microchannels …

Enhancing The Mechanical Properties Of Sla 3d-Printed Bio-Resin From Linseed Oil Using Cellulose And Lignin Biopolymers, Chukwunonso A. Ikedionu

College of Graduate Studies: Theses & Dissertations

Abstract

This research explores the development of bio resin from linseed oil by the process of epoxidation and acrylation to produce acrylated epoxidized linseed oil (AELO). Lignin and cellulose biopolymers were added as reinforcement at varying weight fractions of 1 wt.%, 2.5 wt.%, and 5 wt.%, and their mechanical performance was compared against pure AELO. The formulations were printed using an Elegoo SLA 3D printer to create standardized test specimens like tensile bars, compression cylinders, and hardness blocks, which were all prepared according to the ASTM testing standard.

The results indicate that reinforcement effects depend on both filler type and …

Viscoelastic Property Analysis Of A Magnetorheological Elastomer Micropump For Insulin Delivery In Type 1 Diabetes, Victor Buitimea

College of Graduate Studies: Theses & Dissertations

Over two decades, there has been a significant rise in awareness regarding Type 1 Diabetes (T1D), leading to a deeper comprehension of numerous variables, including hereditary factors, patterns of occurrence, and health challenges. According to the Type 1 Diabetic Index, around 8.7 million people worldwide are affected by this chronic autoimmune illness marked by a lack of insulin and hyperglycemia. The introduction of artificial pancreas systems could save more than half a million patients by 2040. Despite the availability of various insulin delivery technologies that are offered to diabetic patients, many still are skeptical of this modern system. The issues …

Intercellular Mitochondrial Transfer Contributes To Microenvironmental Redirection Of Cancer Cell Fate, Julie Sofie Bjerring, Yara Khodour, Emilee Anne Peterson, Patrick Christian Sachs, Robert David Bruno

School of Medical Diagnostics & Translational Sciences Publications

The mammary microenvironment has been shown to suppress tumor progression by redirecting cancer cells to adopt a normal mammary epithelial progenitor fate in vivo. However, the mechanism(s) by which this alteration occurs has yet to be defined. Here, we test the hypothesis that mitochondrial transfer from normal mammary epithelial cells to breast cancer cells plays a role in this redirection process. We evaluate mitochondrial transfer in 2D and 3D organoids using our unique 3D bioprinting system to produce chimeric organoids containing normal and cancer cells. We demonstrate that breast cancer tumoroid growth is hindered following interaction with mammary epithelial cells …

Traction Force Microscopy Using An Epifluorescence Microscope: Experimental Considerations And Caveats, Zaria Booth, Mazen Mezher, Rudra Patel, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

Forces exerted by cells due to their internal contractility play fundamental roles in a host of processes, including adhesion, migration, survival and differentiation. Traction force microscopy (TFM) enables the determination of forces exerted by cells or cell collectives on their environment, which is typically taken to be an extra-cellular matrix (ECM)-coated substrate. Sample preparation for TFM involves the plating of cells onto an environment embedded with fiducial markers. The imaging of these fiducial markers in the presence and absence of the cells then enables calculation of the displacement of localized regions of the environment, and, consequently, the spatial distribution of …

An Analytical Model Of Motion Artifacts In A Measured Arterial Pulse Signal—Part Ii: Tactile Sensors, Md Mahfuzur Rahman, Subodh Toraskar, Mamun Hasan, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

This paper, the second of two parts, presents an analytical model of motion artifacts (MA) in measured pulse signals by a tactile sensor, which contains a deformable microstructure sitting on a substrate. While the tissue-contact-sensor (TCS) stack and the sensor are both treated as a 1DOF (degree-of-freedom) system, tissue–sensor contact joins their mass together to form a 1DOF system with springs and dampers on both sides. MA on the sensor substrate causes baseline drift and time-varying system parameters (TVSP) of the TCS stack simultaneously. An analytical model is developed to mathematically relate baseline drift and TVSP to a measured pulse …

Scaffolds With Spatiotemporally Controlled Growth Factor Delivery And Cyclodextrin-Enabled Antagonism Of Growth Factor Receptor Sequestration Promote Cutaneous Wound Healing, Jelena Marjanovic, Veronica Jurczuk, Lilian Valadares Tose, Yarixa Cintron Diaz, Francisco Fernandez Lima, Beatriz Abdo Abujamra, Sara Danker, Sinan Jabori, Devinder Singh, Jamie L. Burgess, Joshua Tam, Mohamadmahdi Samandari, Rivka C. Stone, Stephen C. Davis, Robert S. Kirsner, Marjana Tomic-Canic, Fotis M. Andreopoulos, Ivan Jozic

Mechanical & Aerospace Engineering Faculty Publications

Chronic wounds present a major burden to patients, health care professionals, and health care systems worldwide, yet treatment options remain limited and often ineffective. Although initially promising, growth factor-based therapies displayed limited and underwhelming effectiveness largely due to poor bioavailabilbioity and impaired receptor function within the chronic wound microenvironment. Here we demonstrate that chronic wounds exhibit elevated cholesterol synthesis, which disrupts growth factor signaling by sequestering receptors within lipid rafts. To address this, we developed a novel therapy combining growth factors with cyclodextrin in an ECM-mimetic scaffold, enabling localized cholesterol modulation and improved receptor accessibility. We demonstrate that this approach …

The Effect Of Huntington’S Disease On The Mechanical And Electrical Properties Of Red Blood Cells, Liliana Ponkratova

Electronic Theses and Dissertations

Huntington’s disease (HD) has an impact on brain tissues and can alter the biochemical properties of the peripheral blood. Evidence in existing literature suggests that peripheral mutant Huntingtin protein may be involved and deteriorate HD. Red blood cells (RBCs), being the most abundant type of cells in the peripheral blood, can show detectable changes in their biophysical properties due to subtle changes in cell membranes. These changes can offer a minimally invasive means to track the progression of the disease. The transgenic line R6/2 is used as the disease model. Utilizing the electro-deformation spectroscopy, we measured membrane permittivity, cytoplasm conductivity, …

Development Of A Mediation Model Of Pain Cognition In Adult Patients With Sickle Cell Disease, Daniel M. Sop

Theses and Dissertations

Pain is a hallmark of Sickle Cell Disease (SCD), a genetic hemoglobinopathy characterized by chronic hemolytic anemia, vaso-occlusion, and organ damage. While acute vaso-occlusive crises (VOC) have been extensively studied, the mechanisms underlying chronic pain and its interplay with brain function remain unclear. This dissertation investigates the relationships between cerebral blood flow (CBF), fluid cognition, and pain sensitivity in adults with SCD, utilizing advanced imaging techniques and validated assessment tools.

Arterial spin labeling (ASL) and functional magnetic resonance imaging (fMRI) were employed to measure CBF and brain activity, respectively. Pain sensitivity was assessed using the Pain Sensitivity Questionnaire (PSQ), and …

Strength Imbalances And Shoulder Pain In Manual Wheelchair Users Stratified By Age Of Spinal Cord Injury/Disorder (Sci/D) Onset, Ashlyn M. Jones

Theses and Dissertations

Introduction The majority of manual wheelchair users (MWUs) with spinal cord injury or disorder (SCI/D) develop shoulder pain. In adults with SCI/D, there is evidence that upper limb strength imbalances are associated with shoulder pain. However, strength imbalances may indicate protective compensatory strategies, and other factors may be important contributors to pain. Currently, personalized prevention and management of pain is limited, little is known about joint strength imbalances and pain in children who use manual wheelchairs, and the effect of the age of SCI/D onset is poorly understood. The purpose of this study was to assess the effect of age …

Burnout At University: Cross-Sectional Study Among Dental Students, Manal Elhijazi, Hajar Nafia, Ihsane Benyahya

Health Sciences

Context: The university constitutes a demanding and competitive learning environment which can impact the well-being of students. The objective of this survey is to assess the burnout of students at the faculty of dentistry.

Materials and methods: A cross-sectional study was conducted via an anonymous questionnaire with 3 sections: socio-demographic data, lifestyle and habit, and burnout through the Maslach burnout inventory-student survey (MBI-SS) . Continuous variables were presented as means and standard deviations,categorical variables as numbers and percentages. The variables were tested in univariate analysis to assess predictive factors related to burnout using the Khi-2 test. The significance level was …