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Multi-Frequency Processing For Lumen Enhancement With Wideband Intravascular Ultrasound, Rory A. Carrillo

Master's Theses

The application of high frequency ultrasound is the key to higher resolution intravascular ultrasound (IVUS) images. The need to further improve the IVUS spatial resolution may drive the transducer center frequency even higher than the current 40 MHz range. However, increasing the center frequency may be challenging as it leads to stronger scattering echoes from blood. The high level of blood scattering echoes may obscure the arterial lumen and make image interpretation difficult. Blood backscatter levels increase with transmission center frequency at a much greater rate compared to arterial tissue. These different frequency dependencies provide a potential method to distinguish …

Comparing Implementations Of Magnetic-Resonance-Guided Fluorescence Molecular Tomography For Diagnostic Classification Of Brain Tumors, Scott C. Davis, Kimberley S. Samkoe, Julia A. O’Hara, Summer L. Gibbs-Strauss, Keith D. Paulsen, Brian W. Pogue

Dartmouth Scholarship

Fluorescence molecular tomography (FMT) systems coupled to conventional imaging modalities such as magnetic resonance imaging (MRI) and computed tomography provide unique opportunities to combine data sets and improve image quality and content. Yet, the ideal approach to combine these complementary data is still not obvious. This preclinical study compares several methods for incorporating MRI spatial prior information into FMT imaging algorithms in the context of in vivo tissue diagnosis. Populations of mice inoculated with brain tumors that expressed either high or low levels of epidermal growth factor receptor (EGFR) were imaged using an EGF-bound near-infrared dye and a spectrometer-based MRI-FMT …

Design Of A New Suturing And Knot Tying Device For Laparoscopic Surgery, Sinan Onal

USF Tampa Graduate Theses and Dissertations

Minimally invasive or laparoscopic surgery has completely changed the focus of surgery becoming an alternative to various types of open surgery. Minimally invasive surgery avoids invasive open surgery as the operation is performed through one or more small incisions in the abdomen and using a small camera called laparoscope. Through these incisions, surgeons insert specialized surgical instruments to perform the operation resulting in less postoperative pain, shorter hospital stay, and faster recovery. However, the main problems during minimally-invasive surgery are the limited space for operating instruments and the reduced visibility and range of motion inside the patient’s body. During minimally-invasive …

Evaluating Effectiveness Of Best Management Practices To Control Accelerated Sedimentation Of The Morro Bay Estuary, Misgana K. Muleta

Civil and Environmental Engineering

The Morro Bay estuary, located on the central Coast of California approximately half way between Los Angeles and San Francisco, is one of the most important wetlands on the west Coast as it supports wide variety of habitats including numerous sensitive and endangered plant and animal species. Various studies have identified accelerated erosion and subsequent sedimentation as a major threat for sustainability of the bay. Watershed disturbances caused by agricultural activities are believed to be one of the major causes of the accelerated erosion and sedimentation. More than 200 conservation practices have been installed in the watershed since the mid-1990 …

Improved Pcr Design For Mouse Dna By Training Finite State Machines, Salik R. Yadav, Steven M. Corns

Engineering Management and Systems Engineering Faculty Research & Creative Works

This project presents an updated method for classification of polymerase chain reaction primers in mice using finite state classifiers. This is done to compensate for many lab, organism and chemical specific factors that are costly. using Finite State Classifiers can help decrease the number of primers that fail to amplify correctly. for training these classifiers, five different evolutionary algorithms that use an incremental fitness reward are used. Variations to the number of generations and the values in the fitness reward are examined, and the resulting designs are presented. by controlling the fitness reward correctly, there is a potential to develop …

Validation Of A Micro-Ct Approach For Characterization Of Murine And Human Bone In Osteogenesis Imperfecta, John Jameson, Brooke Slavens, Robert Molthen, Peter Smith, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

No abstract provided.

In Vitro Evaluation Of Mechanical Heart Valve Performance Using A Novel Test Chamber In An Automated Mock Circulatory Loop, Antonio Walker

Theses and Dissertations

Valvular heart disease (VHD) continues to have significant effects on many people’s lives, with numbers expected to grow tremendously over the next few years. Individuals suffering from severe valvular heart disease usually require a heart valve transplant in order to restore the native valve’s vital unidirectional flow regulation. Therefore, artificial heart valve (AHV) research is of very high importance. Previous research studies have provided substantial input in the realm of AHV design relative to durability, thrombotic and hemolytic potential, and overall functionality. However, modifications continue to be warranted due to limitations in the accuracy and time efficiency of the in …

A Monocular Marker-Free Gait Measurement System, Jane Courtney, Annraoi M. De Paor

Articles

This paper presents a new, user-friendly, portable motion capture and gait analysis system for capturing and analyzing human gait, designed as a telemedicine tool to monitor remotely the progress of patients through treatment. The system requires minimal user input and simple single-camera filming (which can be acquired from a basic webcam) making it very accessible to nontechnical, nonclinical personnel. This system can allow gait studies to acquire a much larger data set and allow trained gait analysts to focus their skills on the interpretation phase of gait analysis. The design uses a novel motion capture method derived from spatiotemporal segmentation …

Image Processing Algorithms For Diagnostic Analysis Of Microcirculation, Sumeyra Ummuhan Demir

Theses and Dissertations

Microcirculation has become a key factor for the study and assessment of tissue perfusion and oxygenation. Detection and assessment of the microvasculature using videomicroscopy from the oral mucosa provides a metric on the density of blood vessels in each single frame. Information pertaining to the density of these microvessels within a field of view can be used to quantitatively monitor and assess the changes occurring in tissue oxygenation and perfusion over time. Automated analysis of this information can be used for real-time diagnostic and therapeutic planning of a number of clinical applications including resuscitation. The objective of this study is …

3d Micro-Mr And Micro-Ct Models For Determining In-Vivo Function In The Guinea Pig Knee Model Of Osteoarthritis (Oa), Kristoffer W. Dean

Undergraduate Research Opportunities Program (UROP)

Osteoarthritis (OA) is a debilitating disease that affects an estimated 27 million adults in the United States. OA causes damage to cartilage in the joints resulting in bones that rub together. This creates pain, swelling, loss of motion of the joint, and bone spurs. As the number of adults above 65 grows (an estimated 72 million people by 2030) even more people will be at high risk for OA. It is the most common type of arthritis by far yet very little is known about it including relationships between joint structure and function. In 2004, the NIH created the Osteoarthritis …

Process Development For The Fractionation And Isolation Of Corn Fiber Hemicellulose, Justin Montanti

All Theses

Corn fiber is a co-product of the corn wet-milling process that holds potential to become a value-added product. A process was developed to fractionate and isolate the hemicellulose B component of corn fiber generated by corn wet milling. The process consisted of pretreatment by soaking in aqueous ammonia (SAA) of starch-free corn fiber followed by enzymatic cellulose hydrolysis, during which the hemicellulose B was solubilized by cleavage into xylo-oligosaccharides. The hemicellulose A and B fractions were separated by adjustment of pH, and the hemicellulose B recovered by precipitation with ethanol.
The pretreatment step resulted in a high retention of major …

Picasso Interface For Horizon Simulation Framework, Brian E. Kirkpatrick

Master's Theses

The Horizon Simulation Framework, or HSF, is a modeling and simulation framework compiled from C/C++ source code into a command line program. Picasso is an interface designed to control the input files to Horizon by providing visual tools to create and manipulate the XML files used to define an HSF system of assets, their environment, and other simulation parameters. Picasso also supports the visualization of Horizon output in several different forms, and import mechanics from online space object catalogues.

Material Modeling And Analysis For The Development Of A Realistic Blast Headform, S. G. M. Hossain

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Blast traumatic brain injury (BTBI) has become an important topic of study because of the increase of such incidents, especially due to the recent growth of improvised explosive devices (IEDs). This thesis discusses a project in which laboratory testing of BTBI was made possible by performing blast loading on experimental models simulating the human head. Three versions of experimental models were prepared – one having a simple geometry and the other two having geometry similar to a human head. For developing the head models, three important parts of the head were considered for material modeling and analysis – the skin, …

State Estimation For Diffusion Systems Using A Karhunen-Loeve-Galerkin Reduced-Order Model, Justin Mattimore

All Theses

This thesis focuses on generating a continuous estimate of state using a small number of sensors for a process modeled by the diffusion partial differential equation(PDE). In biological systems the diffusion of oxygen in tissue is well described by the diffusion equation, also known by biologists as Fick's first law. Mass transport of many other materials in biological systems are modeled by the diffusion PDE such as CO2, cell signaling factors, glucose and other biomolecules.
Estimating the state of a PDE is more formidable than that of a system described by ordinary differential equations (ODEs). While the state variables of …

Characterization Of Compression Molded Sodium Caseinate-Based Films, Kathryn Hartwig

All Theses

The objective of this research was to characterize compression molded sodium caseinate based films and investigate the effect of water and glycerol ratios on thermal transition and heal sealing properties. Studies were conducted on films from three variations of film-forming mixtures or 'resins', derived from US patent 4,076,846 containing sodium caseinate (NaCas), methylcellulose (MC), calcium chloride (CaCl2), glycerol (Gly), and distilled water. Moisture sorption isotherms were used to evaluate the water-protein and water-glycerol interactions in the resins. Sorption isotherms were characteristic of most biopolymer material and showed increasing moisture sorption with increasing amounts of glycerol. In compression molded films containing …

High School Student Interests In Architecture, Construction, And Engineering Education, Krishna P. Kisi

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is a common and widely held belief that the greatest influencing factor for high school students to enter an architecture-, construction-, or engineering-education program is because either their parents, relatives or friends work or have worked in the industry. However, there is little research that supports this belief. The focus of this research was to analyze characteristics and academic interests of Clark County School District (CCSD) Career and Technical Academies (CATA) students enrolled in architecture, construction and engineering (ACE) curricula.

This research analyzed data collected from a survey conducted by CCSD of their students enrolled in ACE courses. Comprehensive …

Evaluating The Impacts Of Water Conservation Policies On Water Demand, Availability And Outdoor Water Use In The Las Vegas Valley, Kamal Qaiser

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Valley, located in the arid Southern Nevada region, with a growing population, limited water resources, and a prolonged drought, faces a challenge in meeting its future water needs. Southern Nevada Water Authority (SNWA), the main water management agency in the Valley, is focusing on water conservation to reduce water demand. Current water use is 945 lpcd (250 gpcd) which SNWA aims to reduce to 752 lpcd (199 gpcd) by 2035. Presently the indoor outdoor water use proportion is about 40:60 in the Valley. An important component of the Valley's supply are the return flow credits which SNWA …

Pattern Recognition For Fault Detection, Classification, And Localization In Electrical Power Systems, Qais Hashim Alsafasfeh

Dissertations

The longer it takes to identify and repair a fault, the more damage may result in the electrical power system, especially in periods of peak loads, which could lead to the collapse of the system, causing the power outage to extend for a longer period and larger parts of the electrical network. Reducing the outage time and immediate restoration of service can be achieved if the fault type and location are determined in a timely and precise manner.

An integrated algorithm that is based on generating unique signatures from the electric current signal to detect, classify, and localize a fault …

Facial Expression Recognition System, Ewa Piatkowska

Technical Reports

This thesis describes the problem of facial expression recognition in the field of computer vision. Firstly, the psychological background of a problem is presented. Then, the idea of facial expression recognition system (FERS) is outlined and the requirements of such system are specified. The FER system consists of 3 stages: face detection, feature extraction and expression recognition. Methods proposed in literature are reviewed for each stage of a system. Finally, the design and implementation of my system are explained. The face detection algorithm used in the system is based on work by Viola and Jones [13]. The expressions are described …

Investigation Of Potential Pathways And Multi-Cycle Bioregeneration Of Ion-Exchange Resin Laden With Perchlorate, Mohamadali Sharbatmaleki

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ion-exchange (IX) is possibly the most feasible technology for perchlorate removal and perchlorate-selective and non-selective IX resins are commercially available for this purpose. The use of both resins has shortcomings. Selective resins are incinerated after one time use, and non-selective resins produce a regenerant waste stream that contains high concentration of perchlorate. A process involving directly contacting of spent IX resin containing perchlorate with perchlorate-reducing bacteria (PRB) to bioregenerate the resin has been developed and proven recently. In this process PRB biodegrade perchlorate ions which are attached to the functional groups of the resin.

Although its feasibility has been proven, …

Hemocompatibility And Endothelialization Of Elastin And Collagen Scaffolds: The Role Of Plasma Proteins, Shear Stress And Integrins, Nithya Swaminathan

All Theses

Cardiovascular diseases are the leading cause of death worldwide as reported by the World Health Organization. Biomaterials have been extensively used in blood-contacting applications as heart valves, stents, grafts and catheters. However failure due to thrombosis hinders the long term patency and potential of these devices. Purified elastin scaffolds derived from porcine arteries as potential vascular graft materials are being investigated in our laboratory. In this study, we investigated the influence of factors such as shear stress and the presence of plasma proteins on the platelet response, and endothelial cell retention on purified elastin scaffolds to evaluate their hemocompatibility.

Elastin …

Sensor Based Nitrogen Management For Cotton Production In Coastal Plain Soils, Wesley Porter

All Theses

The main objective of this four year study was to develop, refine, and employ sensor-based algorithims to determine the mid season nitrogen requirements for production of irrigated and dryland cotton (Gossypium hirsutum L.) in Coastal Plains soils. The secondary objective of the project was to develop and test equipment for variable rate application of nitrogen to commerical cotton fields utilizing the developed algorithim. Two different production fields at Clemson's Edisto Research and Education Center near Blackville, SC were used. One field, equiped with an overhead irrigation system, was used during the 2007 and 2010 production seasons to develop the algorithm …

In Vitro Analysis Of Auto-Loom Woven Test Patches For Hernia Repair, Bryant Mersereau

All Theses

Hernias are defects in the layers of the abdominal wall that can cause discomfort or pain and lead to serious health problems if left untreated. A significant portion of the world's population is afflicted by hernia formation, and the cost of treating those affected is in the billions of dollars in the US alone. The current best practices for repairing hernias involve the surgical implantation of polymeric meshes over and around the defect site. The mesh, acting as a synthetic replacement for the damaged abdominal wall layers, provides a barrier to further visceral protrusions through the defect, a support framework …

Modeling Of Cell Transfer And Process-Induced Cell Damage In Laser-Assisted Cell Direct Writing, Wei Wang

All Dissertations

Laser-assisted cell direct-write technique has been obtaining more and more attention in different biomaterial direct writing applications. A typical laser-assisted cell direct-write process can be divided into two main stages: the cell droplet ejection and cell droplet landing. The objective of this study is to model the cell mechanical profile during the cell droplet ejection and cell landing and further model the cell damage.
The possible cell damage during the droplet ejection process in laser-assisted cell direct writing may come from two different sources: the phase explosion-induced bubble expansion and the thermoelastic stress wave. The bubble expansion-induced stress wave is …

Simulation And Mathematical Modeling To Support Community-Wide Evacuation Decisions For Multiple Population Groups, Jun Duanmu

All Dissertations

Evacuating a large population from an at-risk area has been the subject of extensive research over the past few decades. In order to measure trip completion and total evacuation times accurately, most researchers have implemented some combination of simulation and optimization methods to provide vehicular flow and congestion data. While the general at-risk population comprises the majority of travelers on the road network, there are often specific groups to consider when assessing the ability to evacuate an entire population. In particular, healthcare facilities (e.g., hospitals) may require evacuation, and the trip times may become an important health issue for patients …

St. Jude Medical: Enhanced Mics (Emics), Devanshi Shah

Master's Theses

Heart disease is one of the most prevalent diseases in the world. The survival chances for patients with ventricular fibrillation/ventricular tachycardia reduces significantly as time passes without treatment and even after getting timely treatment recurring episode are common. These patients can benefit from an Implantable Cardioverter Defibrillator (ICD) which can monitor heart rhythm and provide immediate treatment. Due to the ever changing physical conditions and disease progression, the ICD needs to collect diagnostic data as well as support programming by the physician. The ICD uses inductive telemetry and radio-frequency telemetry for the communication with the external devices such as a …

Immunohistochemical Mapping Of Hypoxia In Ischemic Mouse Hindlimb Skeletal Muscle, Emily Deckert

Biomedical Engineering

The study of blood vessel growth and remodeling is a complex endeavor. Hypoxia, the lack of oxygen in a tissue, is known to stimulate angiogenesis (the growth of new blood vessels), and have little effect on arteriogenesis (the enlargement of existing blood vessels). However, the role of hypoxia in vessel function is unknown, but may be determined using the results and methods developed in this experiment.

Supplied by the bloodstream, oxygen is required by all cells and tissues to remain healthy. If the bloodstream supplying a certain tissue with blood is disrupted, the tissue becomes ischemic, often leading to hypoxia. …

Global Competence: Determination Of Its Importance For Engineers Working In A Global Environment, Gregg M. Warnick

Department of Educational Administration: Dissertations, Theses, and Student Research

We live and work in a world that is even more interconnected and interdependent than ever before. Engineers must now not only develop technical engineering competence, but must also develop additional skills and competencies including global competence to obtain success within a global engineering environment.

The purpose of this study was to determine whether multinational companies considered global competence an important skill in mechanical engineering graduates when making hiring decisions. The study was an exploratory study that utilized an extensive literature review to identify eight global competencies for engineering success within a global environment and also included a survey instrument …

Development Of Tissue Engineered Test Systems To Study Mammary Cell Interactions In Vitro, Cheryl Cass

All Dissertations

The work described in this dissertation was conducted in the interdisciplinary research environment of the Clemson University Institute for Biological Interfaces of Engineering. A note at the beginning of each chapter acknowledges, as relevant, collaborating doctoral students and reminds the reader where work from each chapter has been presented or published. The overall goal of this work was to develop tissue engineered test system methodologies to allow the study of mammary cell interactions in vitro. The background, as described in Chapter 1, was published in part in Philosophical Transactions of the Royal Society A in 2010. The studies were designed …

A Genome-Wide Analysis Reveals No Nuclear Dobzhansky-Muller Pairs Of Speciation Genes Between S. Cerevisiae And S. Paradoxus, But Suggests More Complex Incompatibilities, Katy Kao, Katja Schwartz, Gavin Sherlock

Faculty Publications

The Dobzhansky-Muller (D-M) model of speciation by genic incompatibility is widely accepted as the primary cause of interspecific postzygotic isolation. Since the introduction of this model, there have been theoretical and experimental data supporting the existence of such incompatibilities. However, speciation genes have been largely elusive, with only a handful of candidate genes identified in a few organisms. The Saccharomyces sensu stricto yeasts, which have small genomes and can mate interspecifically to produce sterile hybrids, are thus an ideal model for studying postzygotic isolation. Among them, only a single D-M pair, comprising a mitochondrially targeted product of a nuclear gene …