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Development Of Multi-Shot Parse Mri Techniques, Rajiv G. Menon
Development Of Multi-Shot Parse Mri Techniques, Rajiv G. Menon
All ETDs from UAB
Fast imaging Magnetic Resonance Imaging (MRI) techniques such as Echo Planar Imaging (EPI) often suffer from artifacts such as signal dropouts, geometric distortions and susceptibility artifacts due to background gradients. Parameter Assessment by Retrieval from Signal Encoding (PARSE) was introduced as a single shot, inverse estimation technique that models the MRI process more accurately and estimates the initial transverse magnetization, M0 and its phase, the decay rate R2* and local frequency at each pixel. This technique is devoid of the aforementioned artifacts seen in EPI techniques. The goal of this work is to develop multi-shot parameter assessment by retrieval from …
Membranes For Periodontal Regeneration: From Commercially Available To Spatially Designed And Functionally Graded Materials, Marco Cicero Bottino
Membranes For Periodontal Regeneration: From Commercially Available To Spatially Designed And Functionally Graded Materials, Marco Cicero Bottino
All ETDs from UAB
The aging of the global population will lead to a considerable increase in the number of surgical and restorative procedures related to oral rehabilitation or periodontal regeneration. Periodontitis is one of the most aggressive pathologies that concern the integrity of the periodontal system that can lead to the destruction of the periodontium. Guided tissue and guided bone regeneration (GTR/GBR) have been used for the repair and regeneration of periodontal tissues by utilizing an occlusive membrane.The goal of this dissertation is to advance the knowledge in the area of periodontal regeneration by investigating the properties of a commercially available freeze-dried collagen-based …
Optical Mapping Of The Interactions Between Cardiac Geometry And Electrical Activity, Elliot B. Bourgeois
Optical Mapping Of The Interactions Between Cardiac Geometry And Electrical Activity, Elliot B. Bourgeois
All ETDs from UAB
In healthy hearts, the synchronized spread of electrical activation drives contraction. To investigate the role of cardiac geometry in modulating normal and abnormal electrical rhythms, we stained cardiac tissues with a fluorescent, voltage sensitive dye and imaged activation patterns with fast video cameras (optical mapping). This work is presented in three projects. Computer modeling has shown that conduction velocity increases when fibers are bowed toward the oncoming wavefront and decreases when fibers are bowed in the opposite direction. In the first project, cultured monolayers of cardiac myocytes were optically mapped to experimentally verify the theoretical effect of fiber curvature on …
Increasing The Accuracy Of Dietary Assessments By The Use Of Photogrammetry, David John Brasher
Increasing The Accuracy Of Dietary Assessments By The Use Of Photogrammetry, David John Brasher
All ETDs from UAB
Dietary assessments are plagued by a host of logistical and accuracy problems. The measurement of food consumed is either prohibitively expensive for logistical reasons, or the accuracy is left to the study subject's ability to measure or guess quantities consumed. This dissertation presents a method by which accuracy problems can be reduced with minimal logistical impact. Previous studies have used single photographs to assist in making food measurements during dietary assessments. These single photographs give a twodimensional representation of the food, with extrapolated three-dimensional data. This dissertation adds the third dimension to the volume calculation through the use of photogrammetry. …
A Framework For Composite Service Development: Process-As-A-Concept, Varadraj Prabhu Gurupur
A Framework For Composite Service Development: Process-As-A-Concept, Varadraj Prabhu Gurupur
All ETDs from UAB
This dissertation addresses the problem of bridging the gap that exists between user requirements and the implemented software solution. This gap between the user needs and the actual implementation is usually termed the semantic gap problem. In this dissertation, the software solution is viewed as a composite of available software services and seeking semantically motivated approaches for the composition of a final solution. Representing user needs by capturing the semantic components of these needs and using this representation to build a composite service solution are therefore critical in reducing the aforementioned semantic gap. Although scientists have presented solutions that contribute …
Characterization Of Explanted Endovascular Stents: A Study Of In-Vivo Corrosion And The Role Of Vascular Calcification In Stent Fracture, Dina Halwani
All ETDs from UAB
The electrochemical and mechanical stability of endovascular stents in-vivo is essential for their biocompatibility. Limited information is available regarding the condition of stents following interaction with vascular tissue, as a result, twenty seven stented vessels containing 45 stents (33 bare metal and 12 drug eluting) were retrieved during autopsy and vascular surgery. The stent/tissue components were carefully separated using a rigorous tissue dissolution protocol. Stent surfaces were characterized using 3D digital optical and scanning electron microscopy. Transferred metallic elements in dissolved tissue were measured using mass spectroscopy. Histopathologic assessment of stented tissue, when available, was also performed. Fifteen out of …
Development Of A Multiscale Material Model For Brain Tissue And Its Application To The Impact Response Of The Human Head, Sandeep Kulathu
Development Of A Multiscale Material Model For Brain Tissue And Its Application To The Impact Response Of The Human Head, Sandeep Kulathu
All ETDs from UAB
The development of a finite element model capable of predicting brain injury sustained as a result of an impact load to the head is of considerable importance not only for the development of adequate protection systems but also in deciding an appropriate mode of treatment for an individual. With advancements in imaging technologies, it is now possible to visualize the neuron fiber structures in the brain. In the first half of this project, an analytical micro-mechanical model was developed from the individual isotropic behaviors of the Cerebro-Spinal Fluid (CSF) and brain tissue present in the brain, such that the resultant …
Interface Characterization Of Metal-Thermoplastic Composites, Carol Ochoa Putman
Interface Characterization Of Metal-Thermoplastic Composites, Carol Ochoa Putman
All ETDs from UAB
Hybrid materials featuring thermoplastic polymer composites in conjunction with metals can be used as structural materials in military and commercial transport vehicles and for protection of buildings and infrastructure. Constituent thermoplastics and metals have distinct advantages as protective materials; however, metals on their own are heavy; hence, hybrid materials offer an option as lighter materials. Since the optimal performance of a composite strongly depends on the behavior of the interface, the present study focuses on understanding the mechanisms of mechanical and chemical bonding as well as the effect of thermal stresses at the interface of metal-thermoplastic composites. The mechanical interactions …
Business Models For Commercial-Scale Carbon Dioxide Sequestration; With Focus On Storage Capacity And Enhanced Oil Recovery In Citronelle Dome, Richard A. Esposito
Business Models For Commercial-Scale Carbon Dioxide Sequestration; With Focus On Storage Capacity And Enhanced Oil Recovery In Citronelle Dome, Richard A. Esposito
All ETDs from UAB
Fossil fuels, such as coal and natural gas, currently play an enormous role in our nation's base-load energy supply and provide reliable domestic energy security. If fossil fuels are to remain a component of future energy production in a carbon constrained world, then carbon-neutral energy options must be available. With fossil fuels, point-source environmental control technologies will be required to help comply with future carbon dioxide (CO2) emissions standards. One very promising technology, carbon capture and storage (CCS), consists of the separation of CO2 from the products of combustion of fossil fuels or from fuel gas produced by gasification of …
Cardiovascular Endothelial Regeneration On An Electrospun Scaffold, Xing Zhang
Cardiovascular Endothelial Regeneration On An Electrospun Scaffold, Xing Zhang
All ETDs from UAB
A bi-layer electrospun nano-fibrous scaffold comprising synthetic polymers and natural proteins was constructed as the prototype of an arterial substitute for coronary ar-tery disease. This scaffold featured a highly porous microstructure analogous to native extracellular matrix. Uni-axial tensile test suggested that its excellent mechanical strength could restore normal blood flow immediately after implantation. Subsequent biocompati-bility study demonstrated that scaffolding materials, either traditional or degraded, were non-toxic to the regenerated human endothelium on the luminal layer. Moreover, this re-generated endothelium possessed critical functions, such as the formation of tight junc-tions, the secretion of prostacyclin, and the prevention of platelet adhesion. Thereafter, …
Bridge Weigh-In-Motion For Bridge Safety And Maintenance, Hua Zhao
Bridge Weigh-In-Motion For Bridge Safety And Maintenance, Hua Zhao
All ETDs from UAB
In the U.S., 40% of the bridges are considered defective and are eligible candidates for retrofit and replacement. Without interrupting the traffic and employing pre-weighed vehicles for the load testing, live load model is established and applied for the soft loading test with the application of the latest commercial bridge weigh-in-motion (BWIM) system. Field testing of three simple supported slab-girder concrete bridges on highway I-59, I-459 and I-78 is implemented to test and evaluate the BWIM system. In addition, field testing on highway I-78 is employed for enforcement screening with the comparison of the results acquired from the bending plate …
Pre-Disaster Planning For Transportation Infrastructure Recovery, Stephanie Victoria Watson
Pre-Disaster Planning For Transportation Infrastructure Recovery, Stephanie Victoria Watson
All ETDs from UAB
The US is dependent upon a functioning transportation network for many aspects of daily life, and those aspects that become largely important during times of disaster. For example, emergency medical response is a crucial activity that relies upon a functioning transportation network during regular daily operations as well as during times of emergency. The US has experienced several natural and manmade devastating events within the past decade including the September 11, 2001 terrorist attacks, Hurricanes Ivan, Katrina and Rita, and record flooding in Tennessee. When disasters occur, the potential of disrupting various infrastructures either individually or simultaneously exists. During a …
Spin Echo Ss-Parse: A Parse Mri Method To Estimate R2, R2' And Frequency In A Single Shot, Ningzhi Li
Spin Echo Ss-Parse: A Parse Mri Method To Estimate R2, R2' And Frequency In A Single Shot, Ningzhi Li
All ETDs from UAB
Rapid and accurate mapping of relaxation rates applies to a number of neuroimaging and functional magnetic resonance imaging (fMRI) studies. Previously developed relaxation rate mapping methods are based mostly on non-linear fitting of intensity images. For the first time, this study developed an ultrafast and direct transverse relaxation rate mapping technique, Spin Echo Single-Shot Parameter Assessment by Retrieval from Single Encoding (SE-SS-PARSE). Four useful imaging parameters, local transverse magnetization magnitude (Mxy0), frequency (f), reversible and irreversible transverse re-laxation rate (R2' and R2), can be estimated using an iterative searching algorithm simul-taneously and quantitatively. In addition, the SE-SS-PARSE technique is free …