Biomechanics and Biotransport Commons^™

Investigating Endothelial Damage During Ischemic Stroke Treatment Using In Vitro And Computational Models, Zackary Lorton

Theses and Dissertations

Large vessel occlusion during acute ischemic strokes requires mechanical thrombectomy (MT) procedures using stent retrievers (SR). However, complete clot removal typically takes several attempts, which can amplify endothelial cell injury (EI). This project aims to characterize the extent of EI during MT using an in vitro vascular platform and a finite-element model (FEM). Impact of SR diameter and characterization of SR mechanical forces are assessed and correlated with human umbilical vein endothelial cell (HUVEC) response. HUVECs were seeded on fibronectin (4 µg/cm²) coated true-scale PDMS arterial phantoms with 2.5 mm luminal diameter. Test groups (n=6) either …

An In Vitro Investigation Of Urothelial Cell Function In Response To Hypoxia And Pressure In Relation To Bladder Outlet Obstruction, Britney Hudson

All Dissertations

Bladder outlet obstruction (BOO) is a prevalent urological condition and can be characterized by the presence of lower urinary tract symptoms (LUTS), such as hesitancy, weak stream, and nocturia. The main cause of BOO is a partial blockage of the urethra, which results in elevated voiding pressure, high storage pressure, and tissue ischemia, which are thought to be the triggers of bladder inflammation and subsequent fibrosis. Often patients do not seek treatment until the conditions get severe. Thus, it would be ideal to have an early diagnostic tool to detect changes in the bladder due to BOO. Extracellular vesicles (EVs) …

Identifying Temporomandibular Disorder Morphological Risk Factors Via Explainable Deep Learning And Multiscale Biomechanical Modeling, Shuchun Sun

All Dissertations

Clarifying multifactorial musculoskeletal disorder etiologies supports risk analysis and development of targeted prevention and treatment modalities. Deep learning enables comprehensive risk factor identification through systematic analysis of disease datasets but does not provide sufficient context for mechanistic understanding, limiting clinical applicability for etiological investigations. Conversely, multiscale biomechanical modeling can evaluate mechanistic etiology within the relevant biomechanical and physiological context. We propose a hybrid approach combining 3D explainable deep learning and multiscale biomechanical modeling; we applied this approach to investigate temporomandibular joint (TMJ) disorder etiology by systematically identifying risk factors and elucidating mechanistic relationships between risk factors and TMJ biomechanics and …

Engineering Nanofibers: Laboratory Characterization, Microstructural Analysis, And Image Processing Insights, Sayed Ahmadreza Razian, Mohammad Arjomandi, Kaspars Maleckis

UNO Student Research and Creative Activity Fair

Polymer nanofibers have attracted high interest in a wide array of applications, including biomaterial scaffolding, textiles, sensors, reinforcement in composites, and filtration systems. Many of these applications combine nanofibers into non-woven fabrics for better properties and easier manipulation. The properties and performance of nanofiber-based fabrics are affected by various microstructure parameters, including fiber alignment, diameter, and gap sizes between the nanofibers. These structural parameters can be controlled by adjusting various process parameters during manufacturing process, but the exact process parameter-microstructure relationships vary depending on the polymer system and need to be studied individually. The goal of this study is to …

Mathematical Model Of Oxygen, Nutrient, And Drug Transport In Tuberculosis Granulomas, Meenal Datta, Mccarthy Kennedy, Saeed Siri, Laura Via, James W. Baish, Lei Xu, Veronique Dartois, Clifton Barry, Rakesh Jain

Faculty Journal Articles

Physiological abnormalities in pulmonary granulomas–pathological hallmarks of tuberculosis (TB)–compromise the transport of oxygen, nutrients, and drugs. In prior studies, we demonstrated mathematically and experimentally that hypoxia and necrosis emerge in the granuloma microenvironment (GME) as a direct result of limited oxygen availability. Building on our initial model of avascular oxygen diffusion, here we explore additional aspects of oxy- gen transport, including the roles of granuloma vasculature, transcapillary transport, plasma dilution, and interstitial convection, followed by cellular metabolism. Approximate analytical solutions are provided for oxygen and glucose concentration, interstitial fluid velocity, interstitial fluid pressure, and the thickness of the convective zone. …

Assessing The Relationship Between Contralateral Limb Synergy And Rock Climbing Efficiency, Jeromy Miramontes

Theses, Dissertations and Capstones

Rock climbing is a total body sport testing the mental and physical capabilities of athletes. Efficiency of movement can improve the ability of climbers to perform at a higher capacity and reduce the risk of injury. Data on the relationship between the continuous relative phase (CRP) of contralateral joint rotations and time to completion of a bouldering move are ways to assess rock climbing. This study aimed to assess this relationship, as well as the geometric entropy (GE) of the center of mass displacement when completing the bouldering move, and the metabolic efficiency over 4 min of bouldering. The study …

A 3d Dlt View Correction Tool For Manual Digitizing: A Cross-Platform Application For Correcting Shifted Image Coordinates Prior To Object Coordinate Reconstruction, William Moynihan

Theses, Dissertations and Capstones

While 3D direct linear transformation is a versatile motion capture method, care must be taken so that the cameras are not bumped or adjusted between the object space calibration phase and the end of video recording. Disturbing the cameras during this time will misalign the view, making the movement data invalid for the associated calibration. The purpose of this study was to design and validate a cross-platform software application for transforming image coordinates from a bumped camera to be compatible with the object space calibration and to determine the relationship between reconstruction error and changes to bumped camera views.

For …

Inflammatory Protein Elicitation In Response To Whole-Body Vibration Exposure, Nicholas Miller

Theses, Dissertations and Capstones

This study aimed to assess the effects of whole-body vibration (WBV) on the brain through changes in blood protein concentrations, seat and head accelerations, and symptomatology over time. Subjects were assigned to control, 1-hour, or 8-hour vibration exposure groups. Glial fibrillary acidic protein (GFAP) and S100B concentrations were measured. Root mean square average weighted vibration (A_ws), vibration dose value (VDV), and seat-to-head transmissibility (STHT) were calculated. There were no differences in GFAP (p = 0.79) or S100B (p = 0.97) concentrations between 1-hour and 8-hour subjects (p = 0.79). Average weighted head acceleration (p …

Development Of A Two-Finger Haptic Robotic Hand With Novel Stiffness Detection And Impedance Control, Vahid Mohammadi, Ramin Shahbad, Mojtaba Hosseini, Mohammad Hossein Gholampour, Saeed Shiry Ghidary, Farshid Najafi, Ahad Behboodi

Mechanical & Aerospace Engineering Faculty Publications

Haptic hands and grippers, designed to enable skillful object manipulation, are pivotal for high-precision interaction with environments. These technologies are particularly vital in fields such as minimally invasive surgery, where they enhance surgical accuracy and tactile feedback: in the development of advanced prosthetic limbs, offering users improved functionality and a more natural sense of touch, and within industrial automation and manufacturing, they contribute to more efficient, safe, and flexible production processes. This paper presents the development of a two-finger robotic hand that employs simple yet precise strategies to manipulate objects without damaging or dropping them. Our innovative approach fused force-sensitive …

Matrix Stiffness Sensing By Nascent Adhesions And The Role Of Riam In Adhesion Assembly, Nikhil Mittal

Dissertations, Master's Theses and Master's Reports

Mechanical stiffness of the extracellular matrix (ECM) impacts many cellular functions such as proliferation, migration, and differentiation. ECM stiffness is sensed by a cell via integrin-based focal adhesions (FAs) by changing conformation and biochemical activities of molecules within FAs by the exchange of the force between the ECM and filamentous actin (F-actin). Cells in turn respond to this stiffness by generating traction force that plays an important role in many biological events such as tissue morphogenesis, stem cell differentiation, wound healing, and cancer cell metastasis. The stiffness of the extracellular matrix induces differential tension within integrin-based adhesions. Understanding stiffness sensing …

Fluid Dynamics And Leukocyte Transit In The Lymphatic System, Huabing Li, Jingjing Zhang, Timothy Padera, James W. Baish, Lance Munn

Faculty Journal Articles

The lymphatic system plays a vital role in maintaining fluid balance in living tissue and serves as a pathway for the transport of antigen, immune cells, and metastatic cancer cells. In this study, we investigate how the movement of cells through a contracting lymphatic vessel differs from steady flow, using a lattice Boltzmann-based computational model. Our model consists of cells carried by flow in a 2D vessel with regularly spaced, bi-leaflet valves that ensure net downstream flow as the vessel walls contract autonomously in response to calcium and nitric oxide levels regulated by stretch and shear stress levels. The orientation …

Simultaneous Evaluation Of Tibiofemoral And Patellofemoral Mechanics In Total Knee Arthroplasty: A Combined Experimental And Computational Approach, Yashar A. Behnam, Ahilan Anantha Krishnan, Hayden Wilson, Chadd W. Clary

Center for Orthopaedic Biomechanics: Faculty Scholarship

Contemporary total knee arthroplasty (TKA) has not fully restored natural patellofemoral (P-F) mechanics across the patient population. Previous experimental simulations have been limited in their ability to create dynamic, unconstrained, muscle-driven P-F articulation while simultaneously controlling tibiofemoral (T-F) contact mechanics. The purpose of this study was to develop a novel experimental simulation and validate a corresponding finite element model to evaluate T-F and P-F mechanics. A commercially available wear simulator was retrofitted with custom fixturing to evaluate whole-knee TKA mechanics with varying patella heights during a simulated deep knee bend. A corresponding dynamic finite element model was developed to validate …

The Sexually Dimorphic Role Of Connexin 43 In Bone Remodeling And Disuse-Induced Bone Loss, Gabriel A. Hoppock

Theses and Dissertations

Bone loss is frequently experienced by individuals undergoing long-term disuse, such as prolonged bedrest, immobilization due to paralysis or injury, and conditions such as spaceflight. Under normal physiological conditions, bone remodeling is balanced by bone-forming osteoblasts and bone-resorbing osteoclasts, and the activity of osteoblasts and osteoclasts is orchestrated by osteocytes. Osteocytes are the most abundant cell type found in bone and ample evidence suggests they are bone’s main mechanosensory cell type. Therefore, understanding osteocyte biology and responses to mechanical signals, or lack thereof during unloading, may lead to new therapeutic targets to combat bone loss during disuse. Previous data has …

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …

Getting Off On The Right Foot: Addressing Severe Lymphedema Through A Novel Shoe Design, Carl R. Russell Iii, Anjollie M. Ramakrishna, Christopher H. Johns Iii, Alana V. Van Wijnen

Purdue Journal of Service-Learning and International Engagement

Engineering Projects in Community Service (EPICS) is a service-learning design program run by the College of Engineering at Purdue University. EPICS teaches students design skills by providing solutions for individuals, communities, and organizations in the surrounding area while mirroring engineering industry standards. Biomedical Engineering is a team within EPICS that strives to serve community partners through biomedical applications. HR is a patient who suffers from severe lymphedema. This condition results in her foot swelling three times its original size and requires her to utilize weekly leg compression therapy. Prescription shoes are slightly adequate. However, they lead to sores and pain …

Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump

Electronic Theses and Dissertations

Biomanufactured 3D-organoids show promise for modeling and treating various conditions, particularly insulin-dependent diabetes mellitus (type-1 diabetes). Pancreatic islet organoids serve as sustainable sources of insulin-producing β-cells, potentially restoring insulin regulation in patients and providing a long-term solution for diabetes. Hydrogel droplet printing is an emerging technique in regenerative medicine due to its advantageous tunability and biocompatibility; however, challenges of consistency, quality control, and scalability persist. To address these issues, we developed a novel air-jetting based droplet bioprinting system for the generation of monodispersed alginate micro-droplets. The objective of this project was to incorporate human induced pluripotent stem cells (hiPSCs) into …

Electroencephalography And Biomechanics Of The Basketball Throw, Phong Ky Phan

Theses and Dissertations

According to various studies, compared with novice athletes, experts exhibit superior integration of perceptual, cognitive, and motor skills. This superior ability has been associated with the focused and efficient organization of task-related neural networks. Specifically, skilled individuals demonstrate a spatially localized or relatively lower response in brain activity, characterized as ‘neural efficiency’, when performing within their domain of expertise. Previous works also suggested that elite basketball players can predict successful free throws more rapidly and accurately based on cues from body kinematics. These traits are the result of a prolonged training of specific motor skills and focused excitability of the …

Quantification Of Intervertebral Disc Strain From High-Resolution Ultrasound Imaging During Dynamic Loading, Diya Sakhrani

Discovery Undergraduate Interdisciplinary Research Internship

High-resolution ultrasound imaging employs high-frequency sound waves that can be used to noninvasively visualize the structures within the body, facilitating medical diagnosis without the need for open surgery. The widespread utilization of ultrasound is attributed to its affordability, non-invasive characteristics, and use of non-ionizing radiation. Nevertheless, ultrasound is prone to artifacts originating from the surrounding environment, gas-liquid interfaces, or dense tissue. These artifacts are common in ultrasound images and can cause dropout, noise, and degraded resolution. In this study we analyzed intervertebral disc (IVD) strain during two axial compression testing cycles of bovine intervertebral discs with a 2-dimensional direct deformation …

Characterizing Intervertebral Disc Strain Under Dynamic Loading Conditions Using Ultrasound Texture Analysis, Radhika Kulkarni

Discovery Undergraduate Interdisciplinary Research Internship

Herniated discs in the spine are a significant patient burden, with potential links to lower back and leg discomfort and a considerable impact on daily life. These discs, located between spinal vertebrae, are comprised of the annulus fibrosus (AF) and the nucleus pulposus (NP). Herniations happen when the NP protrudes through a full-thickness annular tear, possibly compressing spinal nerves. The mechanical factors underlying herniated discs are poorly understood, necessitating research into these mechanisms and accessible diagnostic techniques. Our study employs high-resolution ultrasound and texture correlation to quantify strain patterns in intervertebral discs during dynamic loading.

A motion segment from the …

Transport Barriers Influence The Activation Of Anti-Tumor Immunity: A Systems Biology Analysis, Mohammad R. Nikmaneshi, James W. Baish, Hengbo Zhou, Lance L. Munn

Faculty Journal Articles

Effective anti-cancer immune responses require activation of one or more naïve T cells. If the correct naïve T cell encounters its cognate antigen presented by an antigen presenting cell, then the T cell can activate and proliferate. Here, mathematical modeling is used to explore the possibility that immune activation in lymph nodes is a rate-limiting step in anti-cancer immunity and can affect response rates to immune checkpoint therapy. The model provides a mechanistic framework for optimizing cancer immunotherapy and developing testable solutions to unleash anti-tumor immune responses for more patients with cancer. The results show that antigen production rate and …