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Impact Of Salt On Denitrification Potential In Roadside Environments, Nakita A. Lancaster Aug 2012

Impact Of Salt On Denitrification Potential In Roadside Environments, Nakita A. Lancaster

Master's Theses

Urban systems are impacted by changes in hydrology and water chemistry, altering their ability to mitigate detrimental impacts to coastal water bodies, particularly those that result from high volumes of stormwater runoff. The elevated level of impervious cover increases not only runoff but also contaminant loading of nutrients, metals, and road salt used for deicing in cold weather climates. Current stormwater management strategies, while focused on managing the changes in hydrology associated with urbanization, also are designed to mitigate the pollutant loading. Here we investigate the impact that road salt will have on nitrogen removal in roadside environments. Sediments were …


Efficient Algorithms For Sorting On Gpus, Seema M. Munavalli Aug 2012

Efficient Algorithms For Sorting On Gpus, Seema M. Munavalli

Master's Theses

Sorting is an important problem in computing that has a rich history of investigation by various researchers. In this thesis we focus on this vital problem. In particular, we develop a novel algorithm for sorting on Graphics Processing Units (GPUs). GPUs are multicore architectures that offer the potential of affordable parallelism. We present an efficient sorting algorithm called Fine Sample Sort (FSS). Our FSS algorithm extends and outperforms sample sort algorithm presented by Leischner[2], which is currently the fastest known comparison based algorithm on GPUs. The performance gain of FSS is mainly achieved due to the quality of the samples …


Suspended Polypyrrole Films Supporting Alamethicin Reconstituted Bilayer Membranes, Robert Northcutt Aug 2012

Suspended Polypyrrole Films Supporting Alamethicin Reconstituted Bilayer Membranes, Robert Northcutt

Theses and Dissertations

This thesis presents a novel architecture for a sensing element fabricated from a conducting polymer and a bioderived membrane. The thin film device provides controlled, selective ion transport from a chemical concentration and produces measurable electrical signals, ion storage, and small scale actuation. A chemical gradient applied across a bioderived membrane generates ion flow through protein transporters in the presence of a gating signal. A conducting polymer undergoes ion ingress/egress in the presence of an electrical and chemical potential, which causes a change on the polymers conformal backbone. A ligand (or) voltage gated protein in the bioderived membrane results in …


Municipal Wastewater Disinfection With Electromagnetic Waves Using Escherichia Coli Concentration As Measurement Of Quantification, Lauren M. Cagle Aug 2012

Municipal Wastewater Disinfection With Electromagnetic Waves Using Escherichia Coli Concentration As Measurement Of Quantification, Lauren M. Cagle

LSU New Orleans Theses and Dissertations

Wastewater treatment is essential to protecting the environment and human welfare. Although chlorination is widely used, the environmental and health concerns associated with chlorine are growing. Treatment facilities are implementing alternative technologies, though the cost and efficiency associated with these practices leave much room in the wastewater field for innovation.

Hydropath Technologies Limited introduced a piece of equipment that uses the properties of a transformer to pass an alternating electric current through the pipe and into the contents of the channel. Hydroflow claims that the charged microorganisms react with the oppositely charged water molecule to force osmosis and kill the …


Polymers For Delivering A Substance Into A Cell, Kaushal Rege, Ravindra S. Kane, Steven M. Cramer, Sutapa Barua Aug 2012

Polymers For Delivering A Substance Into A Cell, Kaushal Rege, Ravindra S. Kane, Steven M. Cramer, Sutapa Barua

Chemical and Biochemical Engineering Faculty Research & Creative Works

Disclosed herein are polymers that can be made cationic and used to deliver a substance into a cell. Also disclosed are pharmaceutical compositions comprising the polymers and methods of using the polymers.


Cellular Automata-Based Parallel Random Number Generators Using Fpgas, David H.K. Hoe, Jonathan M. Comer, Juan C. Cerda, Chris D. Martinez, Mukul V. Shirvaikar Aug 2012

Cellular Automata-Based Parallel Random Number Generators Using Fpgas, David H.K. Hoe, Jonathan M. Comer, Juan C. Cerda, Chris D. Martinez, Mukul V. Shirvaikar

Electrical Engineering Faculty Publications and Presentations

Cellular computing represents a new paradigm for implementing high-speed massively parallel machines. Cellular automata (CA), which consist of an array of locally connected processing elements, are a basic form of a cellular-based architecture. The use of field programmable gate arrays (FPGAs) for implementing CA accelerators has shown promising results. This paper investigates the design of CA-based pseudo-random number generators (PRNGs) using an FPGA platform. To improve the quality of the random numbers that are generated, the basic CA structure is enhanced in two ways. First, the addition of a superrule to each CA cell is considered. The resulting self-programmable CA …


Preparation And Characterization Of A Self-Crimp Side-By-Side Bicomponent Electrospun Material, Yang Han Aug 2012

Preparation And Characterization Of A Self-Crimp Side-By-Side Bicomponent Electrospun Material, Yang Han

Theses and Dissertations

Bicomponent composite fibers have been widely used in the textile industry and are gaining increasing attention on biomedical applications. In this research, polycaprolactone/poly (lactic acid) side-by-side bicomponent fibers were created for the application of a biodegradable scaffold. The side-by-side structure endowed the fiber with self-crimps when it was processed under certain conditions. This material was produced by electrospinning and collected on a high speed rotating mandrel to get highly oriented fibers. A mechanical stretch at the same direction was done followed by a wet heat treatment for polymer retraction. Crimped fibers were demonstrated by scanning electron microscopy. The quantitative porosity …


Nitric Oxide Releasing Polymers For Vascular Graft Applications, Ifeanyi U. Onyejekwe Aug 2012

Nitric Oxide Releasing Polymers For Vascular Graft Applications, Ifeanyi U. Onyejekwe

Biomedical and Chemical Engineering - Dissertations

Nitric oxide [NO] is an endogenous gas involved in a multitude of physiological functions, ranging from vasodilatation, inflammatory response to inhibition of platelet aggregation. Significant interest exists for therapeutic application of exogenous NO, particularly for the improvement of foreign-body responses of biomaterials. One challenge amongst several others that must be taken into consideration is NO's short half-life, ranging from 2-3 s, in physiological systems. Researchers have worked on synthesizing materials, formally referred to as NO donors/NONOates capable of preserving NO and spontaneous gas release upon contact with blood under physiological conditions. Two groups of these commercially available NO donors known …


The Role Of Fluorescence And Human Factors In Quantitative Transdermal Blood And Tissue Analysis Using Nir Raman Spectroscopy, Bin Deng Aug 2012

The Role Of Fluorescence And Human Factors In Quantitative Transdermal Blood And Tissue Analysis Using Nir Raman Spectroscopy, Bin Deng

Biomedical and Chemical Engineering - Dissertations

This research is part of an ongoing project aimed at the application of combined near infrared (NIR) Raman and fluorescence spectroscopy to noninvasive in vivo blood analysis including but not limited to glucose monitoring. Coping with practicalities of human factors and exploring ways to obtain and use knowledge gained about autofluorescence to improve algorithms for blood and tissue analysis are the general goals of this research. Firstly, the study investigated the various sources of human factors pertinent to our concerns, such as fingerprints, turgor, skin hydration and pigmentation. We then introduced specialized in vivo apparatus including means for precise and …


Self Similar Optical Fiber, Zheng-Xuan Lai Aug 2012

Self Similar Optical Fiber, Zheng-Xuan Lai

Electrical Engineering and Computer Science - Dissertations

This research proposes Self Similar optical fiber (SSF) as a new type of optical fiber. It has a special core that consists of self similar structure. Such a structure is obtained by following the formula for generating iterated function systems (IFS) in Fractal Theory. The resulted SSF can be viewed as a true fractal object in optical fibers. In addition, the method of fabricating SSF makes it possible to generate desired structures exponentially in numbers, whereas it also allows lower scale units in the structure to be reduced in size exponentially. The invention of SSF is expected to greatly ease …


Thermally Actuated Resonant Silicon Crystal Nanobalances, Arash Hajjam Aug 2012

Thermally Actuated Resonant Silicon Crystal Nanobalances, Arash Hajjam

Electronic Theses and Dissertations

As the potential emerging technology for next generation integrated resonant sensors and frequency references as well as electronic filters, micro-electro-mechanical resonators have attracted a lot of attention over the past decade. As a result, a wide variety of high frequency micro/nanoscale electromechanical resonators have recently been presented. MEMS resonators, as low-cost highly integrated and ultra-sensitive mass sensors, can potentially provide new opportunities and unprecedented capabilities in the area of mass sensing. Such devices can provide orders of magnitude higher mass sensitivity and resolution compared to Film Bulk Acoustic resonators (FBAR) or the conventional quartz and Surface Acoustic Wave (SAW) resonators …


Ua66 Ogden College Of Science & Engineering Newsletter, Cheryl Stevens, Dean Aug 2012

Ua66 Ogden College Of Science & Engineering Newsletter, Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Alignment, Clustering And Extraction Of Structured Motifs In Dna Promoter Sequences, Faisal Abdulmalek Alobaid Aug 2012

Alignment, Clustering And Extraction Of Structured Motifs In Dna Promoter Sequences, Faisal Abdulmalek Alobaid

Electrical Engineering and Computer Science - Dissertations

A simple motif is a short DNA sequence found in the promoter region and believed to act as a binding site for a transcription factor protein. A structured motif is a sequence of simple motifs (boxes) separated by short sequences (gaps). Biologists theorize that the presence of these motifs play a key role in gene expression regulation. Discovering these patterns is an important step towards understanding protein-gene and gene-gene interaction thus facilitates the building of accurate gene regulatory network models. DNA sequence motif extraction is an important problem in bioinformatics. Many studies have proposed algorithms to solve the problem instance …


Effects Of Testing Time On Anaerobic Toxicity Assessment, Omolola Atinuke Akintomide Aug 2012

Effects Of Testing Time On Anaerobic Toxicity Assessment, Omolola Atinuke Akintomide

Graduate Theses and Dissertations

Anaerobic digestion has been widely used for wastewater treatment for decades. Several Anaerobic Toxicity tests have been developed to screen wastewater for toxicity and assess the treatability of such toxicants. However, past research and reviews on Biochemical Methane Potential (BMP) test and Anaerobic Toxicity Assay (ATA) were considered in this study.

The experimental tests included ammonium-nitrogen and sodium chloride toxicity tests with varied concentration and solid retention time. These tests were designed to demonstrate the impact of ammonia- nitrogen and sodium chloride on the biological degradation process. The anaerobic test set-up includes bench-scale test reactors and respirometers used for measuring …


Fabrication And Characterization Of Biocomposites From Polylactic Acid And Bamboo Fibers, Sarah E. Royse Aug 2012

Fabrication And Characterization Of Biocomposites From Polylactic Acid And Bamboo Fibers, Sarah E. Royse

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Environmental concerns have been motivating research in the field of biodegradable materials, especially those from biological sources. Polylactic acid (PLA) is one biopolymer with the potential to replace some standard synthetic polymers. PLA is currently used for fibers, medical sutures, and some packaging, but is still used very little compared with synthetic polymers. One thing that can be done to expand the potential applications of PLA is to add fibers to create composite materials. Bamboo is a good choice for these fibers because it is abundant in many parts of the world, grows very quickly, and is widely unused. Composites …


Fabrication And Characterization Of Thermomechanically Processed Sulfur And Boron Doped Amorphous Carbon Films, Lonnie Carlson Aug 2012

Fabrication And Characterization Of Thermomechanically Processed Sulfur And Boron Doped Amorphous Carbon Films, Lonnie Carlson

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Small scale, high power density, reliable, and long-life power supplies would be useful or even critical for space missions or the growing number of microdetectors, microsensors, and miniature vehicles. Alpha or beta particle voltaic devices could satisfy these requirements but have been shown to degrade quickly due to radiation damage. Amorphous carbon (a-C) PN junctions or PIN devices could provide radiation hardness and sufficiently high efficiency. As the range of alpha and beta particles in a-C is ~20-120μm, much thicker films than are typical are needed to maximize collection of the particle energy.

In this work, the fabrication of thermomechanically …


2012 Tsu Undergraduate Research Program, David Owerbach Aug 2012

2012 Tsu Undergraduate Research Program, David Owerbach

Office of Research Institutional Research and Scholarship

No abstract provided.


Investigating The Role Of Mechanosensitive Ion Channels In Urothelial Cell Pressure Mechanotransduction, Shawn Olsen Aug 2012

Investigating The Role Of Mechanosensitive Ion Channels In Urothelial Cell Pressure Mechanotransduction, Shawn Olsen

All Dissertations

Overactive bladder (OAB) is a bladder disorder that is characterized by bladder storage symptoms of urgency with or without urge incontinence, frequency, nocturia, and, as of 2003, affected approximately 16.5% of adults in the United States with an annual treatment cost of over $65 billion. While therapies are available to mitigate the symptoms of OAB, there are no treatments for the cause of OAB, due to the lack of understanding of the etiology of the disorder. Recent research has provided evidence that the bladder urothelium is not just a passive barrier, but is also sensitive to various chemical and mechanical …


Laboratory Characterization And Theoretical Analysis Of Contaminant Mass Transfer, Xiaoling Liu Aug 2012

Laboratory Characterization And Theoretical Analysis Of Contaminant Mass Transfer, Xiaoling Liu

All Dissertations

Chlorinated volatile organic compounds (CVOCs) in fractured, low permeability material can be a long-term source of groundwater contaminants and they are among the most difficult remediation challenges. Thermal methods are a possible remediation option, where heat is used to boil water and the volatile compounds are stripped out by partitioning into the resulting water vapor. Theoretical analysis indicates that only a small fraction of pore water removal may lead to a significant geometric reduction in the dissolved concentration [(Udell(, 1998]. Previous modeling studies [(Falta and Murdoch(, 2011; (Pruess(, 1983] suggest that a lower permeability limit exists for effective mass transfer …


Propagation Of Uncertainty In Light-Frame Wood Buildings, Seyed Masood Hassanzadehshirazi Aug 2012

Propagation Of Uncertainty In Light-Frame Wood Buildings, Seyed Masood Hassanzadehshirazi

All Dissertations

Light-frame wood construction is the most common form of construction for residential and low-rise commercial buildings (e.g. hotels and motels) in North America. In these buildings, shearwalls are the primary systems resisting lateral loads induced by earthquakes and winds. Past earthquake events have revealed that the structural performance of nominally identical light-frame wood buildings varied significantly. Although much research has been conducted investigating the uncertainty in the performance of wood shearwalls and buildings under earthquake loading, the focus of many of these studies was on the uncertainty due to the earthquake motions, referred as earthquake-to-earthquake uncertainty, the influences of variability …


Experimental Composite Guidance Conduits For Peripheral Nerve Repair: An Evaluation Of Ion Release, X. F. Zhang, A. Coughlan, H. O'Shea, Mark R. Towler, S. Kehoe, D. Boyd Aug 2012

Experimental Composite Guidance Conduits For Peripheral Nerve Repair: An Evaluation Of Ion Release, X. F. Zhang, A. Coughlan, H. O'Shea, Mark R. Towler, S. Kehoe, D. Boyd

Chemical and Biochemical Engineering Faculty Research & Creative Works

Poly (lactide-co-glycolide) (PLGA) - Pluronic F127 - glass composites have demonstrated excellent potential, from the perspective of controlled mechanical properties and cytocompatibility, for peripheral nerve regeneration. In addition to controlling the mechanical properties and cytotoxicity for such composite devices, the glass component may mediate specific responses upon implantation via degradation in the physiological environment and release of constituent elements. However, research focused on quantifying the release levels of such therapeutic ions from these experimental medical devices has been limited. To redress the balance, this paper explores the ion release profiles for Si4+, Ca2+, Na+, …


A Novel Haptic Simulator For Evaluating And Training Salient Force-Based Skills For Laparoscopic Surgery, Ravikiran Singapogu Aug 2012

A Novel Haptic Simulator For Evaluating And Training Salient Force-Based Skills For Laparoscopic Surgery, Ravikiran Singapogu

All Dissertations

Laparoscopic surgery has evolved from an 'alternative' surgical technique to currently being considered as a mainstream surgical technique. However, learning this complex technique holds unique challenges to novice surgeons due to their 'distance' from the surgical site. One of the main challenges in acquiring laparoscopic skills is the acquisition of force-based or haptic skills. The neglect of popular training methods (e.g., the Fundamentals of Laparoscopic Surgery, i.e. FLS, curriculum) in addressing this aspect of skills training has led many medical skills professionals to research new, efficient methods for haptic skills training.
The overarching goal of this research was to demonstrate …


Did Mineral Surface Chemistry And Toxicity Contribute To Evolution Of Microbial Extracellular Polymeric Substances?, Jie Xu, Jay M. Campbell, Nianli Zhang, William J. Hickey, Nita Sahai Aug 2012

Did Mineral Surface Chemistry And Toxicity Contribute To Evolution Of Microbial Extracellular Polymeric Substances?, Jie Xu, Jay M. Campbell, Nianli Zhang, William J. Hickey, Nita Sahai

College of Polymer Science and Polymer Engineering

Modern ecological niches are teeming with an astonishing diversity of microbial life in biofilms closely associated with mineral surfaces, which highlights the remarkable success of microorganisms in conquering the challenges and capitalizing on the benefits presented by the mineral-water interface. Biofilm formation capability likely evolved on early Earth because biofilms provide crucial cell survival functions. The potential toxicity of mineral surfaces toward cells and the complexities of the mineral-water-cell interface in determining the toxicity mechanisms, however, have not been fully appreciated. Here, we report a previously unrecognized role for extracellular polymeric substances (EPS), which form biofilms in shielding cells against …


Fabrication Of Printed Substrate For Surface Enhanced Raman Spectroscopy, Ali Eshkeiti Aug 2012

Fabrication Of Printed Substrate For Surface Enhanced Raman Spectroscopy, Ali Eshkeiti

Masters Theses

A novel surface enhanced Raman spectroscopy (SERS) substrate was successfully fabricated on a silicon wafer using inkjet printing and on polyethylene terephthalate (PET) using gravure printing. Silver (Ag) nanoparticle (NP) based ink, was used for roughening of the surface of silicon and PET. A thickness of 400 nm was measured for the printed Ag NP printed film on silicon and the thickness of the single and double layered films on PET were measured as 340 nm and 680 nm, respectively by using vertical scanning interferometry. The Ag NP printed SERS substrate was tested for application with heavy metal compounds like …


Ultrastable Synergistic Tetravalent Rna Nanoparticles For Targeting To Cancers, Farzin Haque, Dan Shu, Yi Shu, Luda S. Shlyakhtenko, Piotr G. Rychahou, B. Mark Evers, Peixuan Guo Aug 2012

Ultrastable Synergistic Tetravalent Rna Nanoparticles For Targeting To Cancers, Farzin Haque, Dan Shu, Yi Shu, Luda S. Shlyakhtenko, Piotr G. Rychahou, B. Mark Evers, Peixuan Guo

Pharmaceutical Sciences Faculty Publications

One of the advantages of nanotechnology is the feasibility to construct therapeutic particles carrying multiple therapeutics with defined structure and stoichiometry. The field of RNA nanotechnology is emerging. However, controlled assembly of stable RNA nanoparticles with multiple functionalities which retain their original role is challenging due to refolding after fusion. Herein, we report the construction of thermodynamically stable X-shaped RNA nanoparticles to carry four therapeutic RNA motifs by self-assembly of reengineered small RNA fragments. We proved that each arm of the four helices in the X-motif can harbor one siRNA, ribozyme, or aptamer without affecting the folding of the central …


Locating And Protecting Facilities Subject To Random Disruptions And Attacks, Hugh Medal Aug 2012

Locating And Protecting Facilities Subject To Random Disruptions And Attacks, Hugh Medal

Graduate Theses and Dissertations

Recent events such as the 2011 Tohoku earthquake and tsunami in Japan have revealed the vulnerability of networks such as supply chains to disruptive events. In particular, it has become apparent that the failure of a few elements of an infrastructure system can cause a system-wide disruption. Thus, it is important to learn more about which elements of infrastructure systems are most critical and how to protect an infrastructure system from the effects of a disruption. This dissertation seeks to enhance the understanding of how to design and protect networked infrastructure systems from disruptions by developing new mathematical models and …


Classification Of Genomic Sequences By Latent Semantic Analysis, Samuel F. Way Aug 2012

Classification Of Genomic Sequences By Latent Semantic Analysis, Samuel F. Way

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Evolutionary distance measures provide a means of identifying and organizing related organisms by comparing their genomic sequences. As such, techniques that quantify the level of similarity between DNA sequences are essential in our efforts to decipher the genetic code in which they are written.

Traditional methods for estimating the evolutionary distance separating two genomic sequences often require that the sequences first be aligned before they are compared. Unfortunately, this preliminary step imposes great computational burden, making this class of techniques impractical for applications involving a large number of sequences. Instead, we desire new methods for differentiating genomic sequences that eliminate …


Shape Memory Assisted Self Healing (Smash) Polymeric And Composite Systems, Erika D. Rodriguez Aug 2012

Shape Memory Assisted Self Healing (Smash) Polymeric And Composite Systems, Erika D. Rodriguez

Mechanical and Aerospace Engineering - Dissertations

My research aims to develop a novel approach that uses the shape memory (SM) effect to aid self healing (SH) polymeric systems that are able to simultaneously close and re-bond cracks with a single thermal stimulus. This new concept is termed shape memory assisted self healing (SMASH). Additionally, a new type of shape memory termed reversible plasticity shape memory (RPSM) was also developed where both the elastic and plastic deformation found after deformation completely recover upon a thermal stimulation. I aim to utilize a broad range of polymeric and composite systems that include a single phase semi-crystalline system, a single …


Peptoid Based Slide Coatings For Disease Detection Via Elisa Microarray Analysis, Melissa Lea Hebert Aug 2012

Peptoid Based Slide Coatings For Disease Detection Via Elisa Microarray Analysis, Melissa Lea Hebert

Graduate Theses and Dissertations

Poly-N-substituted glycines (peptoids) are a very versatile family of synthetic molecules that can be customized for any number of applications. In this study, we chose to use peptoids as a foundation for sandwich ELISA microarray analysis with a long term goal of creating an early detection device for complex diseases such as cancer. The peptoids were designed to self-assemble into microspheres to be used in coatings on the surface of the microarray substrates to increase the surface area available for antibody attachment. This increased antibody density would lead to an increase in the microarray analysis sensitivity and dynamic range. Studies …


Plasmonic Pervaporation Via Gold Nanoparticle-Functionalized Nanocomposite Membranes, Aaron Russell Aug 2012

Plasmonic Pervaporation Via Gold Nanoparticle-Functionalized Nanocomposite Membranes, Aaron Russell

Graduate Theses and Dissertations

Butanol derived from biological feedstocks has significant potential as a liquid fuel source, but the separation methods used in its production can be prohibitively expensive and are therefore currently the subject of extensive research. Pervaporation is a promising membrane process that is effective in butanol separations, but involves a large energy demand. This study examines the possibility of increasing flux and energy efficiency in pervaporation via plasmonic heating of gold nanoparticle-functionalized, polymer nanocomposite membranes (AuNCMs) in lieu of conventional feed heating. An economic analysis demonstrated that plasmonic pervaporation could achieve significant reductions in energy usage and utility cost in butanol …