Biomechanics and Biotransport Commons^™

Musculoskeletal Loads During Stationary Cycling And The Effects Of Pedal Modifications For Knee Osteoarthritis, Rachel Lynn Thompson

Doctoral Dissertations

Knee OA is a deteriorating joint disease affecting 27 million people in the US and current exercise prescriptions may be improved with new knowledge of their effects on muscle forces and joint contact loads. Cycling rather than other exercise modalities is generally considered an alternative for people with knee OA. If these research objectives were achieved, clinicians would have additional tools related to joint contact loads for treating people with OA with an cycling exercise while controlling progression of OA. The long-term goal of this research is to provide a scientific basis for planning, evaluation and improvement of subject-specific rehabilitation …

Role Of Trpv4 In Astrocyte Extracellular Matrix Production, Abby Terlouw

Biomedical Engineering Undergraduate Honors Theses

Traumatic Brain Injury (TBI) is an alteration of brain pathology following damage of the central nervous system (CNS) by an external force. In the CNS, glial scar formation often occurs following TBI, and astrocytes are widely believed to contribute to this scar formation. While the role of astrocytes in extracellular matrix (ECM) production is known, the exact mechanism(s) for this event remain unclear. One possible method is the activation of transient receptor potential vanilloid 4 (TRPV4). TRPV4 is a channel protein found in the astrocyte membrane which has been shown to generate intracellular calcium ions following mechanical stimulation. Previous research …

Chemical And Physical Priming Of Human Mesenchymal Stem Cells To Alter Nonviral Gene Delivery Outcomes, Tyler Kozisek, Andrew Hamann, Amy Mantz, Mathias Schubert, Eva Schubert, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Human Mesenchymal Stem Cells: Human mesenchymal stem cells (hMSCs) are a multipotent cell, meaning they are able to differentiate into a more mature cell type, such as osteocytes, chondrocytes, and adipocytes, that are found in numerous tissues in the human body, such as bone marrow, fat, and muscle. Since hMSCs can be derived from adult human tissues, they do not have the same ethical concern associated with them as other stem cells, such as embryonic stem cells. Due to hMSCs multipotency and ease of obtaining, they have become one of the most widely researched stem cell types in areas such …

Assessment Of The Non-Linear Stress-Strain Characteristics Of Poly (Vinyl Alcohol) Cryogel, Mojdeh Zakeri

Electronic Thesis and Dissertation Repository

Creation of tissue-mimicking constructs is of great importance in the field of biomedical engineering. Poly (vinyl Alcohol) (PVA) is a biomaterial capable of simulating a wide range of geometries and mechanical properties of biological tissues. It is nontoxic, biocompatible, and easy to produce. PVA can be physically crosslinked by repeated cycles of freezing and thawing. The final product of this process is called PVA cryogel (PVA-C). The mechanical properties of PVA-C can be accurately controlled by changing PVA molecular weight, PVA concentration, and number and duration of freeze/thaw cycles (FTC). In this study, the stress-strain behavior of PVA cryogel was …

Validation Of Postural Sway Measurements Using Wii Balance Board, Zachary Meade

UNO Student Research and Creative Activity Fair

Standing balance measurements, such as postural sway, are vital for determining functional ability, risk of falling and recovery of injuries. Often the need to collect data outside of the typical clinical or research setting arises. However, obtaining these measurements outside of a laboratory setting can be very difficult, as the mobility of a laboratory-grade force plate (FP) is minimal, and its cost can be upwards of $20,000. The purpose of this study is to create a cheaper alternative by validating the Wii Balance Board’s (WBB; Nintendo, Redmond, Washington, USA) ability to measure postural sway patterns. The WBB can be acquired …

Peak Vertical Ground Reaction Force & Stance Phase Time To Assess Post-Tka Interlimb Asymmetry, Abderrahman Ouattas

UNO Student Research and Creative Activity Fair

In the US, more than 500,000 TKA surgeries are performed annually, to which 97% of those are led by OA¹. Although knee pain is diminished post-TKA, unilateral efficiency and walking asymmetry is still unresolved several years after the surgery². In fact, within a minimum of 10 years after the primary TKA, almost 50% of patients undergo a secondary TKA on the contralateral limb due to OA progression³. The purpose of this study was to determine if post-Total Knee Arthroplasty peak vertical ground reaction force (pVGRF) asymmetry could be identified using stance phase time differences …

Acl Reconstruction Results In Alterations For Force Control Variability During Multidirectional Force Production, Amelia S. Lanier

UNO Student Research and Creative Activity Fair

After anterior cruciate ligament (ACL) rupture most will undergo reconstructive surgery. Within the first year after surgery 25% of patients will re-tear their ACL. Most of those injured attempt to return to sports which include running and cutting. The ability to produce appropriate ground reaction forces may be crucial for the successful return to sports without re-injury. Understanding stability of multidirectional ground reaction force (mGRF) production in healthy and ACL reconstructed (ACL-r) patients can lend insight to the high instance of re-injury. Typically, stability has been measured using linear analyses, but these analyses cannot capture the subtle time varying changes …

The Effects Of Walking Speed On Gait Propulsion When Wearing An Ankle-Foot Orthosis, Alli Kalina

UNO Student Research and Creative Activity Fair

Peripheral artery disease (PAD) is a cardiovascular disease that results from blockage of one or more arteries in the lower extremity. Often, patients with PAD have reduced ability to push off with the foot at the end of the gait cycle. When walking, the ankle contributes the majority of the power to propel the body into the next step. An ankle-foot orthosis (AFO) is a device that aids in ankle propulsion by increasing the energy return, thus decreasing the ankle deficit in pathological individuals. The purpose is to investigate the effect of walking speed on ankle propulsion during walking. Subjects …

Fluid Flow Characterization And In Silico Validation In A Rapid Prototyped Abdominal Aortic Aneurysm Model, Dean Thomas Wampler

Master's Theses

Aortic aneurysms are the 14^th leading cause of death in the United States. Annually, abdominal aortic aneurysm (AAA) ruptures are responsible for 4500 deaths. There are another 45,000 repair procedures performed to prevent rupture, and of these approximately 1400 lead to deaths. With proper detection, the aneurysm may be treated using endovascular aneurysm repair (EVAR). Understanding how the flow of the blood within the artery is affected by the aneurysm is important in determining the growth of the aneurysm, as well as how to properly treat the aneurysm. The goal of this project was to develop a physical construct …

Estimation Of The Centre Of Mass From Motion Capture And Force Plate Recordings: A Study On The Elderly, Sebastien Cotton, Michele Vanoncini, Philippe Fraisse, Nacim Ramdani, Emel Demircan, Andrew P. Murray, Thierry Keller

Andrew P. Murray

The estimation of the centre of mass position in humans is usually based on biomechanical models developed from anthropometric tables. This method can potentially introduce errors in studies involving elderly people, since the ageing process is typically associated with a modification of the distribution of the body mass. In this paper, an alternative technique is proposed, and evaluated with an experimental study on 9 elderly volunteers. The technique is based on a virtual chain, identified from experimental data and locating the subject's centre of mass. Its configuration defines the location of the centre of mass, and is a function of …

The Effect Of Hyperthermia On Doxorubicin Therapy And Nanoparticle Penetration In Multicellular Ovarian Cancer Spheroids, Abhignyan Nagesetti

FIU Electronic Theses and Dissertations

The efficient treatment of cancer with chemotherapy is challenged by the limited penetration of drugs into the tumor. Nanoparticles (10 – 100 nanometers) have emerged as a logical choice to specifically deliver chemotherapeutics to tumors, however, their transport into the tumor is also impeded owing to their bigger size compared to free drug moieties. Currently, monolayer cell cultures, as models for drug testing, cannot recapitulate the structural and functional complexity of in-vivo tumors. Furthermore, strategies to improve drug distribution in tumor tissues are also required. In this study, we hypothesized that hyperthermia (43°C) will improve the distribution of silica nanoparticles …

Design Of A Device For Measuring Bulk Fluid Flow In Spine Segments Under Tensile Loads, Tysum Ruchti, Anton Bowden

Biomedical Engineering Western Regional Conference

No abstract provided.

Effect Of Multiple Confined Compression/Stress Relaxation Cycles On Cross-Linked Alginate Pore Size., Sindhu Kolar Venkat, Erik L. Risa, Bergren Antell, Maryam Mobed-Miremadi

Biomedical Engineering Western Regional Conference

No abstract provided.

Modeling The Combined Effect Of Convection And Diffusion In Cross-Linked Alginate Capsules, Erik L. Risa, Sindhu Kolar Venkat, Bergren Antell, Maryam Mobed-Miremadi

Biomedical Engineering Western Regional Conference

No abstract provided.

Biophysical Tools To Study Cellular Mechanotransduction, Ismeel Muhamed, Farhan Chowdhury, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

The cell membrane is the interface that volumetrically isolates cellular components from the cell's environment. Proteins embedded within and on the membrane have varied biological functions: reception of external biochemical signals, as membrane channels, amplification and regulation of chemical signals through secondary messenger molecules, controlled exocytosis, endocytosis, phagocytosis, organized recruitment and sequestration of cytosolic complex proteins, cell division processes, organization of the cytoskeleton and more. The membrane's bioelectrical role is enabled by the physiologically controlled release and accumulation of electrochemical potential modulating molecules across the membrane through specialized ion channels (e.g., Na^⁺, Ca²⁺, K^⁺ channels). …

Multi-Scale Assessment Of Bone Mechanics And The Mineral Phase Of Intramuscular Bone Of Atlantic Herring Fish, Svetlana Zeveleva

Dissertations and Theses

Bone tissue is a complex composite structure made up of a soft organic phase consisting of collagen I and non-collagenous proteins, and a hard inorganic phase consisting of mineral nanoplatelets. Given it’s compositional properties, bone is a unique stiff, tough, and strong biomaterial, making it exceptionally difficult to synthesize ex vivo. While the complete hierarchical structure may change with age and population, the basic building block components of mineralized collagen fibrils, are preserved. This study uses a model of intramuscular bone of the Atlantic herring fish, which present a simple structure, and no process of remodeling.

A multi-scale approach …

Mechanical Effects Of Surgical Adhesives On Ascending Thoracic Aortic Aneurysm Replacement, Dong Qiu

Electronic Theses and Dissertations

Ascending thoracic aortic aneurysm (aTAA) is a potentially lethal disease which grows gradually over time and may lead to aortic dissection and rupture. Currently, aTAA surgical repair using Dacron graft is a well-established treatment. In addition, surgical adhesives are frequently used in the surgeries to seal the anastomotic site. This study aims to investigate mechanical effects of four commonly used surgical adhesives, namely BioGlue, CoSeal, Crosseal, and Tisseel, on the suture site using in-vitro digital image correlation (DIC) method and finite element (FE) simulations in an ovine model. In this study, first, mechanical properties of ovine ascending aorta were obtained …

Computational Studies On Biomechanics Of Concussion And On Efficacy Of Football Helmets, David Labyak

Dissertations, Master's Theses and Master's Reports

Football helmets have been used for many years to prevent head injuries to players. Over the years, the helmet design has evolved from a crude leather head covering to the more recent form fitting helmets that are seen today. The one design feature that has been common in the majority of all helmets is a hard polycarbonate shell with a foam cushion padding. The main goal of the padding layer was to reduce the amount of linear acceleration during an impact event. The one feature that has been overlooked is how stiff the padding is in rotation.

The purpose of …

Age-Related Differences In The Lumbopelvic Kinematics During The Trunk Motions In The Anatomical Planes, Milad Vazirian

Theses and Dissertations--Biomedical Engineering

Management and control of the low back pain as an important health problem in the industrial societies necessitates to investigate how the risk of this disease is affected by aging. Since the abnormalities of the lumbopelvic kinematics are related to the existence or risk of low back injuries, the objective of this dissertation was set to find the age-related differences in lumbopelvic kinematics when performing basic trunk motions reaching to range of motion in different anatomical planes.

A cross-sectional study was designed where sixty asymptomatic individuals between 20–70 years old with no confounding health condition, no current or previous highly …

An Enhanced Spring-Particle Model For Red Blood Cell Structural Mechanics: Application To The Stomatocyte–Discocyte– Echinocyte Transformation, Mingzhu Chen, Fergal Boyle

Articles

Red blood cells (RBCs) are the most abundant cellular element suspended in blood. Together with the usual biconcave-shaped RBCs, i.e., discocytes, unusual-shaped RBCs are also observed under physiological and experimental conditions, e.g., stomatocytes and echinocytes. Stomatocytes and echinocytes are formed from discocytes and in addition can revert back to being discocytes; this shape change is known as the stomatocyte–discocyte–echinocyte (SDE) transformation. To-date, limited research has been conducted on the numerical prediction of the full SDE transformation. Spring- particle RBC (SP-RBC) models are commonly used to numerically predict RBC mechanics and rheology. However, these models are incapable of predicting the full …