Biomedical Engineering and Bioengineering Commons^™

Axicons For Improved Resolution And Depth Of Focus In Adaptive Optics Scanning Light Ophthalmoscopy, Ruth E. Woehlke, Robert F. Cooper

Biomedical Engineering Faculty Research and Publications

Adaptive optics scanning light ophthalmoscopes are instrumental for studying the eye, yet they use truncated Gaussian illumination and are limited by diffraction, restricting resolution and depth of focus (DOF). Non-diffractive Bessel beams have emerged as an alternative. Here, we use two axicons configured as: (1) an extended DOF beam for resolving multiple retinal layers; and (2) an annular beam for increasing lateral resolution. We compare both approaches to truncated Gaussian illumination using a variety of metrics. Using Configuration 1, we successfully observed multiple retinal layers simultaneously. Using Configuration 2, we observed enhanced lateral resolution but decreased signal-to-noise ratio.

Advanced Analytical Biosensing For Cancer Detection And Neural Diagnostics Using Tapered Optical Fiber (Tof), Protonic, And High Throughput Microplate –Based Technologie, Bayan Hassan Alharbi

Chemistry & Biochemistry Theses & Dissertations

This dissertation investigates the development and application of advanced biosensing technologies to enhance early disease detection, neurological diagnostics, and bioactive compound evaluation. The research spans four key areas. First, it introduces tapered optical fiber (TOF)-based plasmonic biosensors for the non-invasive detection of prostate cancer, demonstrating high sensitivity and specificity compared to conventional diagnostic methods.

Second, it explores the use of fluorescent biosensors to test the Transmembrane Electrostatically Localized Proton (TELP) theory, shedding light on the role of localized protons in neuronal signaling and energy transfer. Third, the work presents a high-throughput, microplate-based biosensing platform for analyzing mitochondrial function under nanosecond …

Effect Of Moderate Decrease In Contractility On Epithelial Cell-Cell Contacts Under External Stretch, Saika Sharmin

Mechanical & Aerospace Engineering Theses & Dissertations

Epithelial tissues are characterized by extensive cell–cell contacts and often subject to stretch during normal function. Cell-cell contact adhesion strength maintains mechanical continuity from cell to cell. Mechanical forces exerted by cells via actomyosin contractility are known to strengthen cell-cell adhesions to a certain extent. While it is known that a large decrease in contractility causes cell-cell contact rupture due to weakened adhesions, it is unclear how a moderate reduction in contractility affects cell-cell junction stability. Here, we studied how a moderate inhibition of non-muscle myosin II (NMII) affects the integrity of epithelial cell-cell contacts, especially when subject to the …

An Injectable, Dual-Curing Hydrogel For Controlled Bioactive Release In Regenerative Endodontics, Meisam Omidi, Daniela S. Masson-Meyers, Jeffrey M. Toth

Biomedical Engineering Faculty Research and Publications

Regenerative endodontics seeks to restore the vascularized pulp–dentin complex following conventional root canal therapy, yet reliable neovascularization within the constrained root canal remains a key challenge. This study investigates the development of an injectable, dual-curing hydrogel based on methacrylated decellularized amniotic membrane (dAM-MA) and compares its performance to a conventional gelatin methacryloyl (GelMA). The dAM-MA platform was designed for biphasic release, incorporating both free vascular endothelial growth factor (VEGF) for an initial burst and matrix-metalloproteinase-cleavable VEGF conjugates for sustained delivery. The dAM-MA hydrogel achieved shape-fidelity via thermal gelation at 37 °C and possessed tunable stiffness (0.5–7.8 kPa) after visible-light irradiation. …

Anisotropic Object-Based Shifts Of Attention Arise From Unequal Influences Of Visual Field Meridians On Neural Attention Gradients, David H. Hughes, Adam J. Barnas, Adam S. Greenberg

Biomedical Engineering Faculty Research and Publications

Object-based attention prioritizes the processing of information appearing within a selected object. We previously showed an object-based shift direction anisotropy (SDA) whereby horizontal shifts are more efficient than vertical shifts (Barnas AJ, Greenberg AS. Atten Percept Psychophys 78: 1985–1997, 2016; Barnas AJ, Greenberg AS. Vis Cogn 27: 768–791, 2019), an effect modulated by the visual field meridians (Barnas AJ, Greenberg AS. Q J Exp Psychol (Hove) 77: 2516–2532, 2024). Our present aim was to understand how the functional brain mechanisms of attention give rise to the SDA. We hypothesized that the SDA arises from attentional resources being partitioned differently by …

Towards Improving Computational Modeling Of The Lumbar Spine - Impact Of Material Properties And Laminotomy On Spinal Biomechanics, Isaac K. Kumi

Mechanical & Aerospace Engineering Theses & Dissertations

Spinal ligaments play a crucial role in maintaining the mechanical stability of the lumbar spine. These dense, collagenous tissues not only resist excessive motion but also distribute loads between spinal components to protect neural structures. Traditionally, the mechanical response of ligaments has been modeled using linear elastic assumptions, which treat the tissue as having a constant stiffness regardless of loading history. While this simplifies analysis, it fails to capture the time-dependent behaviors, such as creep, stress relaxation, and hysteresis, that are characteristic of biological tissues.

Viscoelastic modeling may provide a more physiologically accurate representation by incorporating both elastic and viscous …

Improving Echocardiographic Aortic Aneurysm Assessment In Marfan Syndrome Patients, Joshua Paik, Shubh P. Mehta, Samskrithi Sivakumar, Felix Dinklage, Ahhyun Lee, Benjamin J. Landis, Craig J. Goergen

Discovery Undergraduate Interdisciplinary Research Internship

Marfan syndrome (MFS) is a genetic connective tissue disorder caused by a variant of the fibrillin-1 (FBN1) gene, leading to abnormalities in organs reliant on tissue elasticity. Proximal thoracic aortic aneurysms (TAAs) are a major clinical concern, particularly in pediatric MFS patients, due to their risk of dissection or rupture. Diagnosis and monitoring of TAAs often depend on manual measurements of aortic root diameters from the parasternal long axis views of transthoracic echocardiograms. However, this method is prone to interobserver variability (IOV), which impacts consistency in clinical assessment. To mitigate these limitations, we developed a graphical user interface (GUI) that …

Sex-Dependent Differences In Cardiac Function And Strain In Doxorubicin-Induced Cardiomyopathy, Anna J. A. Webb, Bea O. Cabot, Aasish Chowdary, Wilhelm S. Smith, Benjamin Zeidler, Cortland H. Johns, Craig J. Goergen

Discovery Undergraduate Interdisciplinary Research Internship

Doxorubicin is a chemotherapeutic agent used to treat many types of cancer. While effective, doxorubicin can cause cardiomyopathy, a disease affecting the heart muscle. Although the effects of doxorubicin on the heart are well studied, the mechanisms leading to cardiomyopathy are not well understood. Previous studies have used murine models to study the cardiotoxicity of doxorubicin. These reports showed that cardiac dysfunction is more pronounced in male compared to female mice. The goal of this study is to further evaluate sex differences in doxorubicin induced cardiomyopathy using 4-dimensional strain mapping techniques. In this study, both female and male C57Bl/6J mice …

A Dna Damage Analysis Of Breast Cancer Cells Under Cyclic Mechanical Actuation, Maria C. Macias, Madison Howard, Luis Solorio

Discovery Undergraduate Interdisciplinary Research Internship

Metastasis is the leading cause of mortality in breast cancer, yet tumor cell behavior and their response to mechanical cues in the pre-metastatic niche remains poorly understood. This study investigates how breast cancer cells respond to strain mimicking lung tissue dynamics, with a focus on DNA damage. Using a custom-designed micro-actuating lung model, we cultured mApple at p53BP1 and H2B-GFP reporter cells on fibrillar fibronectin-coated substrates subjected to cyclic mechanical forces that simulate respiratory motion. A group of cells were treated with escalating concentrations of Niraparib (0.1–10 µM), a PARP inhibitor, as a positive control. To visualize and quantify DNA …

Investigation Into Intraocular Pressure Distribution Via Computer Aided Engineering (Cae), Madison Maureen Hinman

Masters Theses

The leading cause for irreversible blindness and vision loss is glaucoma - an eye condition associated with elevated intraocular pressure (IOP). Increased IOP is also seen during other pathological conditions like spaceflight-associated neuro-ocular syndrome (SANS), and non-pathological conditions as when playing a wind instrument. The study aimed to describe the influence of different vitreous cavity size as well as vitreous fluid viscosity on the IOP as measured at the back of the eye on the retina. Improved understanding of eye pressure transmission can aid in a better understanding of eye diseases. The experiment conducted included cavities of varying size and …

Advancements In Microarray Manufacturing Enable Emerging Technologies, Kendall Hoff

Biomedical Engineering ETDs

Significant advances in manufacturing technologies have enabled the production of new DNA microarrays for use in emergent technology. Photolithography, wafer scale manufacturing, and improvements in synthesis chemistry and design enable high-throughput production of extremely high-quality arrays. These new arrays offer extremely high oligonucleotide densities, in the range of tens of thousands of oligonucleotides per square micron. They also offer smaller features sizes, with millions of features per square centimeter. Furthermore, they can be manufactured with the DNA tethered at either end to the surface, leaving either the 5’ or 3’ end free and available for use in enzymatic reactions; and …

Targeted Delivery Of Rapamycin Via Epidermal Growth Factor Receptors In Pancreatic Cancer Cells Inhibits Cell Proliferation And Induces Apoptosis, Adeolu S. Oluremi, Christofer Baldwin, Nickolas L. Gustavision, Mujeebat Bashiru, Adeniyi Nsiah Oyebade, Noureen Siraj, Raj Raghavendra Rao, N. Ali

Biomedical Engineering Faculty Publications and Presentations

Pancreatic cancer (PC) is aggressive and deadly; most PC cells overexpress an epidermal growth factor receptor (EGFR). EGFR-targeting peptide (GE11) was conjugated to gold nanoparticles (AuNPs) for delivering rapamycin (Rap), an mTOR inhibitor that reduces proliferation and induces apoptosis. Biophysical techniques confirmed the conjugation. Rap loading efficiency was 41.5%, with sustained release at a lower pH. Conjugates showed higher uptake in PANC-1 cells than unmodified AuNPs. It also inhibited proliferation and induced apoptosis via pathways involving reactive oxygen species, mitochondrial damage, and caspase activation. This approach represents a promising nanoparticle-based therapeutic strategy targeting PC cells, utilizing GE11-EGFR interactions to minimize …

Targeting Poor Solubility Of Docetaxel: Computational Screening Of Ionic Liquids Using Cosmo-Rs, Najihah Mohd Noor, Amal A.M. Elgharbawy, Huma Warsi Khan, Yumi Zuhanis Has-Yun Hashim, Muhammad Moniruzzaman, Mohd Firdaus Abd. Wahab, Hamzah Mohd Salleh, Siti Nur Idayu Matusin

Publications and Research

Docetaxel (DTX), a chemotherapeutic agent widely used in cancer treatment, has limited therapeutic efficacy owing to its poor oral absorption and low bioavailability. This study aims to improve DTX solubility by predicting its compatibility with ionic liquids (ILs) using conductor-like screening model for real solvents (COSMO-RS) computational modelling. A library of 340 ILs comprising 17 cations and 20 anions was screened for their potential to dissolve DTX, with a particular focus on imidazolium-based ILs that enhance its solubility and pertinence to cytotoxic applications. Computational analysis identifies ILs containing cations such as 1-methylimidazolium [MIM] and 1,3-dimethylimidazolium [DMIM] and anions such as …

Uptake, Distribution, And Activity Of Pluronic F68 Adjuvant In Wheat And Its Endophytic Bacillus Isolate, Anthony Cartwright, Mohammad Zargaran, Anagha Wankhade, Astrid Jacobson, Joan E. Mclean, Anne J. Anderson, David W. Britt

Biological Engineering Student Research

Surfactants are widely utilized in agriculture as emulsifying, dispersing, anti-foaming, and wetting agents. In these adjuvant roles, the inherent biological activity of the surfactant is secondary to the active ingredients. Here, the hydrophilic non-ionic surface-active tri-block copolymer Pluronic^® F68 is investigated for direct biological activity in wheat. F68 binds to and inserts into lipid membranes, which may benefit crops under abiotic stress. F68’s interactions with Triticum aestivum (var Juniper) seedlings and a seed-borne Bacillus spp. endophyte are presented. At concentrations below 10 g/L, F68-primed wheat seeds exhibited unchanged emergence. Root-applied fluorescein-F68 (fF68) was internalized in root epidermal cells and …

A Longitudinal Analysis Of Morphological Shape Variation Of Spleen In Patients With Fontan Surgery, Varatharajan Nainamalai, Håvard Bjørke Jenssen, Mostafa Rezaeitaleshmahalleh, Djinaud Prophete, Jordan Gosnell, Sarah Khan, Marcus Haw, Jingfeng Jiang, Joseph Vettukattil

Michigan Tech Publications

Background: Splenic size serves as a surrogate biomarker for predicting portal vein hyper-tension and liver abnormalities in subjects with Fontan Associated Liver Disease (FALD). We analyze the long-term shape variation of the spleen in FALD subjects using morphological shape features of radiomic features. Methods: We used 154 (84 from computed tomography and 70 from magnetic resonance) image volumes obtained from 36 individuals who underwent stage 3 Fontan procedure and 145 computed tomography images from controls to assess splenomegaly. To understand the splenomegaly, thirteen shape features of the spleen over three 10-year intervals, and variations between controls and FALD subjects were …

Vibration-Based Detection For The Monitoring Of Neonatal Bcpap Respiratory Support To Minimize Duration Of Disconnections, Kaitlyn G. Calabresi, Meera R. Bhat, Lavinia L. Kong, Eli J. Foster, Jonathan Wang, Sangeeta Koilada, Angela Mak, Aastha Kapadia, Niam Mohseni, W. Keith Leung, Suneetha Desiraju, Constanza Miranda

School of Medicine Faculty Publications

Bubble continuous positive airway pressure (bCPAP) is a minimally invasive respiratory support for neonates experiencing respiratory distress syndrome (RDS). It exerts continuous, oscillatory air pressure to encourage lung function and development. Neonates’ movement may cause disconnections at the nasal interface. These disconnections are characterized by the cessation of bubbling at the bCPAP respiratory circuit output and frequently go unnoticed until hypoxia develops. Common Neonatal Intensive Care Unit (NICU) bCPAP systems lack a built-in alarm or accessory device to monitor for disconnections. As a result, nursing personnel must exercise extreme caution utilizing current bCPAP procedure. If a neonate is disconnected, it …

Exploring The Effect Of Led-To-Photodetector Spacing On Subcutaneous Photoplethysmography For Continuous Blood Pressure Measurement, Dario Cabal, Brian Nguyen, David B. Green, Kevin Kilgore, Varun Thakkar, Michael J. Fu, Steve J. Majerus

Student Scholarship

Photoplethysmography (PPG) is widely used to measure heart rate, blood oxygenation, and more recently, blood pressure. Implanted PPG systems offer the possibility to measure similar real-time measures of cardiovascular health, however, the detection method may vary due to a lack of capillary vessels for PPG sensors to observe in muscle tissue. To improve volumetric blood detection in large muscles, without relying on the capillary density of skin, a flexible PPG sensor was developed. The sensor included multiple spacing of illuminating infrared (IR) light emitting diodes (LEDs) and a single IR photodetector. This arrangement was expected to enable detection of blood …

Upcycling Of Polydicyclopentadiene (Pdcpd) Via Dynamic Bonds, Catherine Biju

Biomedical Engineering ETDs

Thermoset polymers are valued for their exceptional mechanical strength and thermal stability, but suffer from irreversibility due to permanent covalent crosslinks, limiting recyclability. Polydicyclopentadiene (pDCPD), a widely used thermoset, exemplifies this limitation despite its excellent mechanical properties. In this study, we report an upcycling strategy for pDCPD through the incorporation of dynamic imine bonds. The successful integration of imine bonds was confirmed by ¹H NMR spectroscopy. Mechanical testing revealed that the modified pDCPD (pDCPD-imine) exhibits enhanced tensile strength and maintains its performance across multiple reprocessing cycles. Moreover, the dynamic nature of the imine bonds imparts healability to the network. This …

Impactor Displacement As A Predictor Of Thoraco-Abdominal Organ Injury: Comparison Of Isolated Organ To Whole Body Tests, Jack Seifert, Jared Michael Koser, Alok Shah, Lance Frazer, Frank A. Pintar, Narayan Yoganandan, Dan Nicolella, Timothy B. Bentley, Brian D. Stemper

Biomedical Engineering Faculty Research and Publications

Purpose

Body armor is used to protect the wearer from penetrating injuries. However, when the armor defeats the projectile, it deforms at high rates into the wearer, referred to as back face deformation (BFD). This deformation can cause a variety of superficial and internal injuries and consequently should be considered when designing body armor. However, current design standards do not adequately consider the effects of BFD, and new data are necessary to inform future design thresholds for BFD. The objective of this study was to develop blunt impact injury risk curves for in vitro thoraco-abdominal organs and determine their applicability …

Development And Characterization Of Pmma/Pvp Nanofiber-Loaded Bioactive Agents With Enhanced Breast Cancer Activity, Samar A. Salim, The British University In Egypt, Esraa Abdelazim, Marwa Abdel Aleem

Nanotechnology Research Centre

Breast cancer remains a leading cause of cancer-related mortality globally, driving the need for novel effective and less toxic therapeutic agents. This study explores the synthesis and characterization of bioactive compounds: 1-(4-methoxyphenyl)-N- (p-tolyl)methanimine (MPTI), N-(4-methylphenyl)benzamide (MPB), and 4-methyl-N-(p-tolyl)benzenesulfonamide (MTS), and their incorporation into a PMMA/PVP polymer matrix for potential anticancer applications. Morphological analysis of the PMMA/PVP-loaded agents via SEM depicts structural modifications in the PMMA/PVP nanofibrous matrix upon incorporation of the bioactive agents. The FTIR analysis of the synthesized compounds before and after loading into the 7PMMA:3PVP nanofibers reveals successful incorporation of MPTI, MPB, and MTS, with characteristic absorption bands …