Engineering Commons^™

Bioengineering Embryonic Microenvironment For Exploring Stem Cell-Breast Cancer Cell Interactions, Nurazhani Abdul Raof

Legacy Theses & Dissertations (2009 - 2024)

Embryonic stem (ES) cells and breast cancer cells share similar signaling pathways that allow cells to proliferate and differentiate. However, signaling molecules in cancer cells are misexpressed. Cell microenvironments that consist of many factors such as soluble factors, extracellular matrices, and neighboring cells, play a pivotal role in determining cellular fate. The exposure of ES cell microenvironments to cancer cells may address the missing components in the tumor microenvironment, which could inhibit tumorigenesis or reprogram cancer cells into a less invasive phenotype. In this thesis, in vitro ES cell microenvironments have been engineered three-dimensionally via alginate hydrogel encapsulation and patterned …

A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud

IP Theory

No abstract provided.

Long-Term Follow Up Of Van Nes Rotationplasty For Proximal Focal Femoral Deficiency, Haluk Altiok, Jeffrey D. Ackman, Ann Flanagan, Mary Peer, Adam Graf, Joseph Krzak, Sahar Hassani, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Proximal focal femoral deficiency (PFFD) is a congenital anomaly that presents challenges for orthopaedic and prosthetic management. The Van Nes rotationplasty is one treatment in which the extremity is surgically rotated to utilize the ankle and foot as a functional knee joint in a prosthesis. The purpose of this study is to determine the long-term functional and quality of life (QOL) outcomes for individuals who have undergone rotationplasty surgery for congenital PFFD compared to age and gender matched controls.

Estimation Of Organ And Effective Dose Due To Compton Backscatter Security Scans, Michael Hoppe, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose: To estimate organ and effective radiation doses due to backscatter security scanners using Monte Carlo simulations and a voxelized phantom set. Methods: Voxelized phantoms of male and female adults and children were used with the GEANT4 toolkit to simulate a backscatter security scan. The backscatter system was modeled based on specifications available in the literature. The simulations modeled a 50 kVp spectrum with 1.0 mm-aluminum-equivalent filtration and a previously measured exposure of approximately 4.6 μR at 30 cm from the source. Photons and secondary interactions were tracked from the source until they reached zero kinetic energy or exited from …

A Database For Estimating Organ Dose For Chest And Head Ct Scans For Arbitrary Spectra And Angular Tube Current Modulation, Franco Rupcich, Andreu Badal, Iacovos Kyprianou, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose: The purpose of this study was to develop a database for estimating organ dose in a voxelized patient model for coronary angiography and brain perfusion CT acquisitions with any spectra and angular tube current modulation setting. The database enables organ dose estimation for existing and novel acquisition techniques without requiring Monte Carlo simulations. Methods: The study simulated transport of monoenergetic photons between 5 and 150 keV for 1000 projections over 360◦ through anthropomorphic voxelized female chest and head (0◦ and 30◦ tilt) phantoms and standard head and body CTDI dosimetry cylinders. The simulations resulted in tables of normalized dose …

Exploring Functional Networks Of The Brain Relating To Upper Extremity Motor Skill Using Graph Theory, Dominic Nathan, Stephen J. Guastello, Robert W. Prost, Dean C. Jeutter

Biomedical Engineering Faculty Research and Publications

No abstract provided.

Dataglove Measurement Of Joint Angles In Sign Language Handshapes, Petra Eccarius, Rebecca Bour, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

In sign language research, we understand little about articulatory factors involved in shaping phonemic boundaries or the amount (and articulatory nature) of acceptable phonetic variation between handshapes. To date, there exists no comprehensive analysis of handshape based on the quantitative measurement of joint angles during sign production. The purpose of our work is to develop a methodology for collecting and visualizing quantitative handshape data in an attempt to better understand how handshapes are produced at a phonetic level. In this pursuit, we seek to quantify the flexion and abduction angles of the finger joints using a commercial data glove (CyberGlove; …

Remembering Forward: Neural Correlates Of Memory And Prediction In Human Motor Adaptation, Robert A. Scheidt, Janice Zimbelman, Nicole M.G. Salowitz, Aaron J. Suminski, Kristine M. Mosier, James Houk, Lucia Simo

Biomedical Engineering Faculty Research and Publications

We used functional MR imaging (FMRI), a robotic manipulandum and systems identification techniques to examine neural correlates of predictive compensation for spring-like loads during goal-directed wrist movements in neurologically-intact humans. Although load changed unpredictably from one trial to the next, subjects nevertheless used sensorimotor memories from recent movements to predict and compensate upcoming loads. Prediction enabled subjects to adapt performance so that the task was accomplished with minimum effort. Population analyses of functional images revealed a distributed, bilateral network of cortical and subcortical activity supporting predictive load compensation during visual target capture. Cortical regions – including prefrontal, parietal and hippocampal …

Football Helmet Fitment And Its Effect On Helmet Performance, Ron Jadischke

Wayne State University Theses

A method and system to objectively quantify helmet fitment was designed and developed. It measures the pressure between the energy-absorbing material in the helmet and the athlete's head. This system is also capable of measuring surface pressure during impact events. A volunteer-based field study was conducted to quantify how helmets were fitting athletes in a real-life setting. The helmets fit athletes in varying degrees of tightness and evenness. Most athletes (59%) had the highest pressures in the frontal area and 29% had the highest pressure in the occipital area. A large-sized helmet on the Hybrid III headform represented how most …

Contact Pressure Distribution Of Osteochondral Defects Of The Knee: Effects Of Non-Vertical Walls, Scott Ensminger

Wayne State University Theses

Purpose: To examine the relationship between well-shouldered osteochondral defects and

defects of different geometries by studying their effects on rim stress concentration and

load redistribution in the human knee.

Methods: Ten fresh-frozen cadaveric knees were mounted at 30° of flexion in a materials

testing machine. Digital electronic pressure sensors were placed in the medial and lateral

compartments of the knee. Dynamic pressure readings were recorded throughout the

loading and holding phases as each knee was loaded to 700N and held for 5 seconds.

Artificial defects were created in each knee to simulate well-shouldered defects and

beveled-defects. Loading was repeated for …

Traumatic Brain Injury Induced Cerebral Blood Flow Changes - A Potential Role For Caffeine, Sharath Chandra Reddy Bandaru

Wayne State University Theses

Traumatic brain injury (TBI) is a global health problem with significant socio-economic costs. Closed head TBIs are one of the major causes of physical disability and cognitive disorder in young adults and a leading cause of death in children.

Alteration in cerebral blood flow due to an impaired autoregulation is one of the most common consequences of TBI. However, studies related to understanding the temporal changes in CBF following TBI in experimental models are limited. The few available studies report acute reduction in CBF following TBI; knowledge related to CBF changes at sub-acute periods extending to 7 days after TBI …

Neurophysiological Changes In Spinal Nerve Roots Subjected To Tensile Loading At Several Strain Rates, Gurjiwan Singh Virk

Wayne State University Theses

ABSTRACT:

Spinal nerve roots have been implicated in many types of traumatic injuries such as motor vehicle accidents, falls, and sports injury, causing damage to brachial plexus and lumbosacral plexus. They have also been involved in lower back pain, disc herniation or protrusions, sciatica, and traumatic birth delivers such as shoulder dystocia. These roots undergo tension, resulting in traumatic axonal injury (TAI), which is also one of the consequences of traumatic brain injury (TBI). Every year about 2 million cases of TBI are reported nationwide with variable neurological deficits. Thus, it is important to understand the neurophysiological response and injury …

Functional Electrical Stimulation In Spinal Cord Injury Rehabilitation, Meir Hildeshaim

The Science Journal of the Lander College of Arts and Sciences

The following is an excerpt from the introduction to this article: Spinal cord injury is defined as a “disconnection syndrome” that results in a loss of ability of the spinal cord to communicate ascending and/or descending impulses (Hamid and Hayak 2008). Due to its role as the primary conduit of motor and sensory impulses, spinal cord injury is widely regarded as one of the most catastrophic, survivable injuries a person can suffer. Depending on the severity and placement of the injury, the patient can experience a wide range of disability or death. A mild injury may result in the patient …

Multimodal Imaging Evidence For Axonal And Myelin Deterioration In Amnestic Mild Cognitive Impairment, Brian T. Gold, Yang Jiang, David K. Powell, Charles D. Smith

Neuroscience Faculty Publications

White matter (WM) microstructural declines have been demonstrated in Alzheimer's disease and amnestic mild cognitive impairment (aMCI). However, the pattern of WM microstructural changes in aMCI after controlling for WM atrophy is unknown. Here, we address this issue through joint consideration of aMCI alterations in fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity, as well as macrostructural volume in WM and gray matter compartments. Participants were 18 individuals with aMCI and 24 healthy seniors. Voxelwise analyses of diffusion tensor imaging data was carried out using tract-based spatial statistics (TBSS) and voxelwise analyses of high-resolution structural data was conducted using …

Complete Genome Sequence Of Clostridium Clariflavum Dsm 19732, Javier A. Izquierdo, Lynne Goodwin, Karen W. Davenport, Hazuki Teshima

Dartmouth Scholarship

Clostridium clariflavum is a Cluster III Clostridium within the family Clostridiaceae isolated from thermophilic anaerobic sludge (Shiratori et al, 2009). This species is of interest because of its similarity to the model cellulolytic organism Clostridium thermocellum and for the ability of environmental isolates to break down cellulose and hemicellulose. Here we describe features of the 4,897,678 bp long genome and its annotation, consisting of 4,131 protein-coding and 98 RNA genes, for the type strain DSM 19732.

Application Of The Human-Machine Interaction Model To Multiple Attribute Task Battery (Matb): Task Component Interaction And The Strategy Paradigm, Craig M. Walters

Browse all Theses and Dissertations

The Multiple-Attribute Task Battery (MATB) is composed of four simultaneously running components to which a human operator responds. A prior report has quantified information content as a machine input baud rate using the Hick-Hyman and Fitt's Laws for three of the four components and defines a strategy function. This report covers methods to quantify information content of the fourth component, creating a single metric which describes overall task complexity and evaluates human performance and strategy. Six MATB task-scenarios (combinations of two, three, or all four MATB components) each at two input baud rates are evaluated. Subjects were also provided with …

Regulation Of The Transcription And Subcellular Localization Of The Tumor Suppressor Pten By Δnp63Α, Mary Kathryn Leonard

Browse all Theses and Dissertations

Non-melanoma skin cancers (NMSCs) are the most common form of cancer in the United States with an estimated 3.5 million new cases each year. Surgical excision is the main treatment for NMSC, but leaves the potential for disfiguring scars and does not fully reduce the risk of recurrence since the surrounding tissue is also sun damaged and may contain tumor-promoting mutations. By understanding the molecular etiology of NMSC we may be able to expand treatment options to more than just resection. Normal epidermal development is dependent upon the expression of the transcription factor p63. Amplification of the ΔNp63α isoform is …

Validation Of Computational Fluid Dynamic Simulations Of Membrane Artificial Lungs With X-Ray Imaging, Cameron Christopher Jones

Theses and Dissertations--Biomedical Engineering

The functional performance of membrane oxygenators is directly related to the perfusion dynamics of blood flow through the fiber bundle. Non-uniform flow and design characteristics can limit gas exchange efficiency and influence susceptibility of thrombus development in the fiber membrane. Computational fluid dynamics (CFD) is a powerful tool for predicting properties of the flow field based on prescribed geometrical domains and boundary conditions. Validation of numerical results in membrane oxygenators has been predominantly based on experimental pressure measurements with little emphasis placed on confirmation of the velocity fields due to opacity of the fiber membrane and limitations of optical velocimetric …

Use Of Hybrid Diffuse Optical Spectroscopies In Continuous Monitoring Of Blood Flow, Blood Oxygenation, And Oxygen Consumption Rate In Exercising Skeletal Muscle, Katelyn Gurley

Theses and Dissertations--Biomedical Engineering

This study combines noninvasive hybrid diffuse optical spectroscopies [near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS)] with occlusive calibration for continuous measurement of absolute blood flow (BF), tissue blood oxygenation (S_tO₂), and oxygen consumption rate (VO₂) in exercising skeletal muscle. Subjects performed rhythmic dynamic handgrip exercise, while an optical probe connected to a hybrid NIRS/DCS flow-oximeter directly monitored oxy-, deoxy-, and total hemoglobin concentrations ([HbO₂], [Hb], and [tHb]), S_tO₂, relative BF (rBF), and relative VO₂ (rVO₂) in the forearm flexor muscles. Absolute baseline BF and …

Bisphosphonates And Bone Microdamage, William A. Caruthers

Theses and Dissertations--Biomedical Engineering

Osteoporosis is a significant healthcare issue due to the increasing elderly population. Bisphosphonates are used to treat osteoporosis by reducing the rate of resorption, increasing bone mineral density (BMD) and thereby reducing fracture risk. Long-term bisphosphonate treatment, however, has been associated with low-energy fractures. Bone microdamage may provide a partial explanation for one of the mechanisms responsible for these fractures since it has been shown to reduce bone toughness, fracture resistance, and bone strength. The goal of this study was to quantify the changes in bone microdamage parameters with the duration of bisphosphonate treatment. This study selected, stained, and histomorphometrically …

Noninvasive Assessment And Modeling Of Diabetic Cardiovascular Autonomic Neuropathy, Siqi Wang

Theses and Dissertations--Biomedical Engineering

Noninvasive assessment of diabetic cardiovascular autonomic neuropathy (AN): Cardiac and vascular dysfunctions resulting from AN are complications of diabetes, often undiagnosed. Our objectives were to: 1) determine sympathetic and parasympathetic components of compromised blood pressure regulation in patients with polyneuropathy, and 2) rank noninvasive indexes for their sensitivity in diagnosing AN. Continuous 12-lead electrocardiography (ECG), blood pressure (BP), respiration, regional blood flow and bio-impedance were recorded from 12 able-bodied subjects (AB), 7 diabetics without (D0), 7 with possible (D1) and 8 with definite polyneuropathy (D2), during 10 minutes supine control, 30 minutes 70-degree head-up tilt and 5 minutes supine recovery. …

Ultrasonic Concentration Of Microorganisms, Samuel J. Mullins

Theses and Dissertations--Biosystems and Agricultural Engineering

Concentration of microorganisms from a sample volume would increase the limits of detection of samples used for rapid-detection methods. Rapid detection methods are is advantageous for the food industry to rapidly test for bacteria in order release products on a timely basis. Ultrasonic concentration was considered a promising method for manipulation of microorganisms. An ultrasonic chamber consisting of parallel piezoceramic discs with a reticulated polyurethane foam mesh was used to concentrate Saccharomyces cerevisiae yeast and Escherichia coli bacteria. The concentration of yeast was seen to increase by 200% (from 8.0 x 10⁴ cells mL^-1 to 2.4 x 10 …

Development Of A Bi-Directional Electronics Platform For Advanced Neural Applications, Luca Abbati

USF Tampa Graduate Theses and Dissertations

This work presents a high-voltage, high-precision bi-directional multi-channel system capable of stimulating neural activity through bi-phasic pulses of amplitude up to ∓50 V while recording very low-voltage responses as low as tens of microvolts. Most of the systems reported from the scientific community possess at least one of the following common limitations: low stimulation voltages, low gain capabilities, or insufficient bandwidth to acquire a wide range of different neural activities.

While systems can be found that present remarkable capabilities in one or more specific areas, a versatile system that performs over all these aspects is missing. Moreover, as many novel …

Effect Of Ascorbic Acid On Cdte Quantum Dots And Investigation Of Different Chemical Sensors On Cdtehg Quantum Dots, Yamini Chitrala

Bioengineering Theses - Archive

The objective of my thesis is to investigate the effect of ascorbic acid on CdTe quantum dots, which is an antioxidant. It was observed that the quantum dots recovered their luminescence intensity after the interaction of the ascorbic acid, where the intensity was quenched by the photosensitizer. The luminescence intensity increased gradually for 0.1mM- 0.5mM concentration of ascorbic acid and remained stable with higher concentrations of the antioxidant. Also, it was observed that under some reaction conditions like pH, temperature and concentration, ascorbic acid had a great influence on its photoluminescence. In the second part of the research project, I …

Cytotoxicity Evaluation Of Methacrylate-Based Resins For Clinical Endodontics In Vitro, Chul Ahn, Aniket S. Wadajkar, Qiang Zhu, Esteban G. Garza, Lynn A. Opperman, Larry L. Bellinger, Takashi Komabayashi

Bioengineering Faculty Publications - Archive

This study examines the cytotoxicity of Super-Bond C&B (SB-C&B), Super-Bond RC Sealer (SB-RC), MetaSEAL (Meta), and AH Plus Sealer (AH+). Freshly mixed and set materials (100 mg) were prepared in vitro and placed in cell culture medium (1 mL) for the working time and for 6 h, respectively. L929 cells seeded into 96-well plates at 5,000 cells/ well were incubated with the eluted medium (200 μL) for 24 h. Cells cultured with medium alone served as the control. Cytotoxicity was evaluated by MTS assay and analyzed with ANOVA. In the freshly mixed group, the average ± SD (%) for cell …

5 Cm Gap Injury Repair: Growth Factor Support And Functional Analysis In A Rabbit Common Peroneal Nerve Model, Princy K. Prasad

Bioengineering Theses - Archive

Nerve conduits have shown to successfully bridge nerve gaps of ≤ 3 cm; however repair of longer, mixed or motor nerve gaps still remains a clinical challenge. In order to study regeneration techniques in clinically relevant long gaps, larger animal models are required. Standardized methods to evaluate functional outcome are necessary to clinically translate experimental treatments. In this study, the capability of the biodegradable and transparent cross-linked doped polyester elastomer (CUPE) to serve as a nerve conduit material in a multiluminal nerve conduit across a 5 cm gap in a rabbit common peroneal nerve model was evaluated. The effect of …

Near Infrared Quantitative Phase Imaging Of Cellular Manipulation Under Different Physio-Chemical Environments, Bipin Joshi

Bioengineering Theses - Archive

Quantitative phase imaging using Digital Holographic Microscopy (DHM) is emerging as a label-free and wide-field method of characterizing cells with high spatio-temporal resolution. In parallel, silicon based micromechanical and electronic devices are allowing both manipulation (e.g. electrical stimulation, mechanical actuation) as well as characterization (electrical and mechanical) of micro and nano-scopic samples. This has revolutionized development of lab-on-a-chip devices for high throughput analysis of cells and molecules for diagnosis of disease and screening of drug-effects. However, very little progress has been made in optical (e.g. fluorescence, Raman etc) characterization of samples on these silicon-based devices. Especially, wide-field high-resolution optical imaging …

Detecting Clinical Biomarkers Using Diffusion Tensor Imaging, Tejasvi Gundapuneedi

Bioengineering Theses - Archive

Diffusion tensor imaging (DTI), a modality of MRI that measures water diffusion properties noninvasively, is highly sensitive to subtle structural changes of white matter. It provides a unique and noninvasive method for delineating in-vivo architecture of human brain white matter. Four metrics derived from DTI, fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AxD) and radial diffusivity (RD), have been widely used to quantitatively characterize the white matter disruption in mental disorders and degenerative diseases. An atlas-based approach incorporating a digital white matter atlas and registration and skeletonization functions of tract-based spatial statistics (TBSS) has been developed recently. This approach …

Electrospun Biodegradable Polymeric Membranes For Post-Surgery Anti-Adhesion Applications, Pouriska Kivanany

Bioengineering Theses - Archive

Abdominal adhesion is a prevalent, troublesome condition occurring after surgical procedures and can cause a variety of side effects such as, abdominal pain with a highly associated cost ($1.3 billion annually for) for expensive surgical removal. Many companies and research groups have studied and developed techniques to prevent adhesion after surgery; however, none have been completely effective or practical for use. Current materials have many drawbacks, such as the inability to degrade, poor surgical handling, and attracting bacteria. Up to 93% of patients receiving abdominal surgeries will develop abdominal adhesions, and a viable treatment option needs to be developed to …

Involvement Of Mixed Lineage Leukemia And Homeobox Proteins In Dna Damage Recognition And Repair, Somdutta Chakraborty

Bioengineering Theses - Archive

Deoxyribonucleic Acid (DNA) molecules are informational molecules, encoding genetic information which is indispensable in the development and functioning of living organisms. DNA encodes for most proteins essential for all bodily functions and a few of which are known to be involved in the DNA Damage Response/ Repair mechanism. DNA damage recognition and repair is crucial and the cell has an innate mechanism of repairing it. Unrepaired DNA damage leads to genetic mutation or even cancers, which are sustained by further cell division and genetic multiplication. Other researchers have already confirmed the involvement of several proteins and histones like PARP and …