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Do Canines Experience The Effects Of Heart Rate Turbulence?, Melanie Ann Gurunathan Jun 2009

Do Canines Experience The Effects Of Heart Rate Turbulence?, Melanie Ann Gurunathan

Master's Theses

Background

The canine cardiac system has been the model against which many Class III cardiac devices are validated. Thus, it is expected that the canine heart has very similar electrical model to that found in humans. In 1999, the absence of Heart Rate Turbulence (HRT) after a single Pre-Ventricular Contraction (PVC) was linked to high-risk patient after acute myocardial infarction. Studies of HRT were performed on high-risk patients with Holter-Monitors as were most subsequent HRT studies. If HRT could potentially be used as a risk factor of heart disease, it is interesting to study whether HRT is present following a …


Preparation And Characterization Of Electrospun Poly(D, L-Lactide-Co-Glycolide) Scaffolds For Vascular Tissue Engineering And The Advancement Of An In Vitro Blood Vessel Mimic, Tiffany Richelle Pena Jun 2009

Preparation And Characterization Of Electrospun Poly(D, L-Lactide-Co-Glycolide) Scaffolds For Vascular Tissue Engineering And The Advancement Of An In Vitro Blood Vessel Mimic, Tiffany Richelle Pena

Master's Theses

PREPARATION AND CHARACTERIZATION OF ELECTROSPUN POLY(D,L-LACTIDE-CO-GLYCOLIDE) SCAFFFOLDS FOR VASCULAR TISSUE ENGINEERING AND THE ADVANCEMENT OF AN IN VITRO BLOOD VESSEL MIMIC

Tiffany Richelle Peña

Currently, an estimated 1 in every 3 adult Americans are affected by one or more cardiovascular complications. The most common complication is coronary artery disease, specifically atherosclerosis. Outcomes of balloon angioplasty treatments have been significantly improved with the addition of drug eluting stents to the process. Although both bare metal and drug eluting stents have greatly increased the effectiveness of angioplasty and decreased the occurrence of restenosis, several complications still exist. For this reason, the stent …


Time-Mode Circuits For Analog Computation, Vishnu Ravinuthula, Vaibhav Garg, John G. Harris, José A.B. Fortes Jun 2009

Time-Mode Circuits For Analog Computation, Vishnu Ravinuthula, Vaibhav Garg, John G. Harris, José A.B. Fortes

Electrical and Computer Engineering Faculty Research & Creative Works

We introduce time-mode circuits, a set of basic circuit building blocks for analog computation using a temporal step function representation for the inputs and outputs. These novel time-mode circuits are low power, provide good noise performance and offer improved dynamic range. The design, IC implementation and detailed theoretical signal-to-noise ratio (SNR) analysis of a prototype time-mode circuit-a weighted average computation circuit-are discussed. This new way of computation is studied with respect to existing conventional voltage-mode and current-mode circuits. Two possible applications of these time mode circuits are presented: an edge detection circuit for 16 pixels and a 3-tap FIR filter …


Effects Of Learning Rate On The Performance Of The Population Based Incremental Learning Algorithm, Ganesh K. Venayagamoorthy, K. A. Folly Jun 2009

Effects Of Learning Rate On The Performance Of The Population Based Incremental Learning Algorithm, Ganesh K. Venayagamoorthy, K. A. Folly

Electrical and Computer Engineering Faculty Research & Creative Works

The effect of learning rate (LR) on the performance of a newly introduced evolutionary algorithm called population-based incremental learning (PBIL) is investigated in this paper. PBIL is a technique that combines a simple genetic algorithm (GA) with competitive learning (CL). Although CL is often studied in the context of artificial neural networks (ANNs), it plays a vital role in PBIL in that the idea of creating a prototype vector in learning vector quantization (LVQ) is central to PBIL. In PBIL, the crossover operator of GAs is abstracted away and the role of population is redefined. PBIL maintains a real-valued probability …


Learning Nonlinear Functions With Mlps And Srns, R. Cleaver, Ganesh K. Venayagamoorthy Jun 2009

Learning Nonlinear Functions With Mlps And Srns, R. Cleaver, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, nonlinear functions generated by randomly initialized multilayer perceptrons (MLPs) and simultaneous recurrent neural networks (SRNs) are learned by MLPs and SRNs. Training SRNs is a challenging task and a new learning algorithm - DEPSO is introduced. DEPSO is a standard particle swarm optimization (PSO) algorithm with the addition of a differential evolution step to aid in swarm convergence. The results from DEPSO are compared with the standard backpropagation (BP) and PSO algorithms. It is further verified that functions generated by SRNs are harder to learn than those generated by MLPs but DEPSO provides better learning capabilities for …


Machine Annotation Of Traditional Irish Dance Music, Bryan Duggan Jun 2009

Machine Annotation Of Traditional Irish Dance Music, Bryan Duggan

Doctoral

The work presented in this thesis is validated in experiments using 130 realworld field recordings of traditional music from sessions, classes, concerts and commercial recordings. Test audio includes solo and ensemble playing on a variety of instruments recorded in real-world settings such as noisy public sessions. Results are reported using standard measures from the field of information retrieval (IR) including accuracy, error, precision and recall and the system is compared to alternative approaches for CBMIR common in the literature.


Clustered Wireless Sensor Networks, Renita Margaret Machado May 2009

Clustered Wireless Sensor Networks, Renita Margaret Machado

Dissertations

The study of topology in randomly deployed wireless sensor networks (WSNs) is important in addressing the fundamental issue of stochastic coverage resulting from randomness in the deployment procedure and power management algorithms. This dissertation defines and studies clustered WSNs, WSNs whose topology due to the deployment procedure and the application requirements results in the phenomenon of clustering or clumping of nodes. The first part of this dissertation analyzes a range of topologies of clustered WSNs and their impact on the primary sensing objectives of coverage and connectivity. By exploiting the inherent advantages of clustered topologies of nodes, this dissertation presents …


Reliability Of Resting Brain Networks Using Fmri, Suril Rajeshkumar Gohel May 2009

Reliability Of Resting Brain Networks Using Fmri, Suril Rajeshkumar Gohel

Theses

Resting state FMRI studies on human subjects are primarily focused on elaborating effects of resting state brain networks on task induced paradigm and to check consistency of these networks between different groups of populations. Recent studies have shown consistency of RSFC networks within same subjects with intra-site and intra-session variation.

The primary objective of this study was to check consistency of resting state networks between sites and between different groups of people in spite of change in scanning parameters and population. A total of 437 subjects resting state FMRI data from six different sites were collected varying in age group …


An In Vitro Study To Characterize A New Automated High Throughput Neuronal Stretch Injury System, Nicolae Valerian Hususan May 2009

An In Vitro Study To Characterize A New Automated High Throughput Neuronal Stretch Injury System, Nicolae Valerian Hususan

Theses

Traumatic brain injury (TBI) is one of the most prevalent long-term neurological conditions and its overall economic consequences rival that of stroke. Considering the importance of the topic, new models for studying TBI are often designed and created. Based on a model developed by the University of Pennsylvania, NJIT constructed a fully automated version, which injures neuronal cell cultures in uniaxial regime and provides the high experimental yield required in pharmaceutical and neuroscience studies.

In this investigation, a new methodology for culturing primary cortical neurons of rat origin was established. Viable cell cultures developed for the first time in NJIT …


In Vitro Comparison Of A New Stand-Alone Anterior Lumbar Interbody Cage Device With Established Fixation Techniques, Nitin Chawla May 2009

In Vitro Comparison Of A New Stand-Alone Anterior Lumbar Interbody Cage Device With Established Fixation Techniques, Nitin Chawla

Theses

Around 70% of the population in the United States experience low back pain at some point of their lives, of these 4% underwent surgical intervention on the lumbar spine to relieve the pain. Spinal arthrodesis, i.e. joint fusion, is beneficial in many cases as the final option for patients suffering from certain types of low back pain (LBP). In order to promote solid fusion across a decompressed spinal segment, interbody spacers/cages are used with and without posterior instrumentation to provide an initial "rigid" fixation of the segment.

In this study three fresh/frozen human cadaveric lumbar spines were used. Each lumbar …


Development Of An Experimental System To Determine The Contribution Of Titin And Collagen To Passive Stiffness Of Myocardium, Saurin Bharat Shah May 2009

Development Of An Experimental System To Determine The Contribution Of Titin And Collagen To Passive Stiffness Of Myocardium, Saurin Bharat Shah

Theses

Diastolic dysfunction is known to be a major factor for congestive heart failure in aged humans and other mammals. The main contributors to increase in the myocardial stiffness, hindering the cardiac mechanics, are alterations in intracellular titin and extracellular collagen matrix. Titin is a giant extensible protein, the third filament of striated muscle after actin and myosin, which provides elasticity to passive sarcomeres. The aim of this study is to develop an efficient experimental system that will prove to be instrumental in comparing the contribution of titin against collagen to the passive stiffness of cardiac muscle extracted from experimental animals …


Computational Modeling Of The Internal Structure In The Breast, Jordan Greenlee May 2009

Computational Modeling Of The Internal Structure In The Breast, Jordan Greenlee

Electrical Engineering Undergraduate Honors Theses

Many researchers who are using microwave modality in the area of breast cancer detection employ oversimplified models of the internal structure of the breast. Use of engineered or biologically inaccurate models could render inaccurate results. Therefore, a mathematical biological model is implemented in this work and aims to bridge the gap between biologists and engineers. The results of the proposed breast duct model show that older women have smaller breast ducts leading to less dense breasts, which is in agreement with medical knowledge. Also, younger women have larger breast ducts leading to more dense breasts which are consistent with the …


Rainwater Harvesting Pilot Project Report, Liam Mccarton, Sean O'Hogain, Anna Reid, Niamh Mcintyre, Jenny Pender May 2009

Rainwater Harvesting Pilot Project Report, Liam Mccarton, Sean O'Hogain, Anna Reid, Niamh Mcintyre, Jenny Pender

Reports

The rainwater harvesting pilot project was commissioned by the National Rural Water Monitoring Committee in 2005 to assess the feasibility of supplementing treated mains water used for non-potable purposes. The project involved the design, installation, commissioning and monitoring of rainwater harvesting facilities in a rural housing development in County Carlow and in a 250-acre livestock farm in County Meath. Construction was carried out between 2005-2007.


Design, Construction, And Testing Of A New Class Of Mobile Robots, Ivan Siles May 2009

Design, Construction, And Testing Of A New Class Of Mobile Robots, Ivan Siles

All Theses

This thesis introduces a novel mobile robot design concept aimed at exploration of subterranean spaces. The key innovation is the combination of highly maneuverable body elements with wheel/leg elements (Whegs). This combination offers performance not possible with conventional 'monolithic' wheeled or tracked mobile robots, or with current robot snakes. The thesis covers four design iterations of the concept, concentrating on describing the overall design process and results from field tests. Additionally a kinematic analysis of the fourth prototype and implications for future designs is presented.


Towards Dynamical Systems Approach To Fuzzy Clustering, Vladik Kreinovich, Olga Kosheleva May 2009

Towards Dynamical Systems Approach To Fuzzy Clustering, Vladik Kreinovich, Olga Kosheleva

Departmental Technical Reports (CS)

In many application areas, there is a need for clustering, and there is a need to take fuzzy uncertainty into account when clustering. Most existing fuzzy clustering techniques are based on the idea that an object belongs to a certain cluster if this object is close to a typical object from this cluster. In some application areas, however, this idea does not work well. One example of such application is clustering in education that is used to convert a detailed number grade into a letter grade.

In such application, it is more appropriate to use clustering techniques which are based …


Magnetically Anchored "Reduced Trocar" Laparoscopy: Evolution Of Surgical Robotics, Richard Bergs May 2009

Magnetically Anchored "Reduced Trocar" Laparoscopy: Evolution Of Surgical Robotics, Richard Bergs

Bioengineering Theses - Archive

Laparoscopic surgery has become increasingly popular over the last few years due to its benefits; lower morbidity, less perceived pain, better cosmesis results, and less hospital time. For the surgeon however, there are fundamental issues that can make a laparoscopic procedure more difficult than simple open surgery; loss of tactile feel, limited working envelope, high demand for hand-eye coordination, and one trocar-port required for each tool. A revolutionary concept of using magnetics to support tooling across the abdominal wall was conceived by Dr. Jeffrey Cadeddu and his colleagues at the University of Texas Southwestern Medical Center. Collectively referred to as …


Distribution Tridimensionnelle De La Lumière Dans Une Strucutre De Tête D’Adulte Dérivée D’Un Acte Irm: Approche Par La Méthode De Monte Carlo, Chemseddine Mansouri, Jean-Pierre L'Huillier, Nasser H. Kashou May 2009

Distribution Tridimensionnelle De La Lumière Dans Une Strucutre De Tête D’Adulte Dérivée D’Un Acte Irm: Approche Par La Méthode De Monte Carlo, Chemseddine Mansouri, Jean-Pierre L'Huillier, Nasser H. Kashou

Biomedical, Industrial & Human Factors Engineering Faculty Publications

No abstract provided.


High-Rate Channel Catfish Fingerling Production In The Partitioned Aquaculture System, Tim Wells May 2009

High-Rate Channel Catfish Fingerling Production In The Partitioned Aquaculture System, Tim Wells

All Theses

The objective of this 4-year research project was to evaluate the performance of channel catfish (Ictalurus punctatus) fingerling production in the Partitioned Aquaculture System (PAS). The goal was to demonstrate production of 80-gram minimum sized fingerlings in a single growing season, allowing for 100% market-size fish production after one additional season in the grow-out PAS.
A series of 2-inch airlift pumps fed by a single 3-hp low-head blower was found to be capable of supplying sufficient water flow-rate (in 2005, 2006, and 2007) of gpm per container to 9 cohorts. A series of 0.75-hp axial flow pumps (in 2005, 2006, …


Effect Of Molecular Weight Reduction By Gamma Irradiation On The Antimicrobial Activity Of Chitosan, Ebuel Sirmats May 2009

Effect Of Molecular Weight Reduction By Gamma Irradiation On The Antimicrobial Activity Of Chitosan, Ebuel Sirmats

All Theses

The antimicrobial effectiveness of lower molecular weight (LMW) chitosan solutions was tested against Listeria innocua inoculated on TSA and MOX agar plates by the direct droplet method. The chitosan solutions were prepared by dissolving chitosan in 1% (v/v) acetic acid at concentrations ranging from 0.5 to 2.0% and irradiating with Co60 gamma rays ranging from 1 to 20 kGy. MW measurements of chitosan were determined by using HPSEC-MALLS-RI. The MW of chitosan varied from 114.8 kDa to 17.4 kDa and decreased with increasing irradiation dosages. Plate counts on TSA agar from shaker flask assays showed no significant differences among chitosan …


Theoretical Analysis Of Alendronate And Risedronate Effects On Canine Vertebral Remodeling And Microdamage, Xiang Wang, Antonia M. Erickson, Matthew R. Allen, David B. Burr, R. Bruce Martin, Scott J. Hazelwood May 2009

Theoretical Analysis Of Alendronate And Risedronate Effects On Canine Vertebral Remodeling And Microdamage, Xiang Wang, Antonia M. Erickson, Matthew R. Allen, David B. Burr, R. Bruce Martin, Scott J. Hazelwood

Biomedical Engineering

Bisphosphonates suppress bone remodeling activity, increase bone volume, and significantly reduce fracture risk in individuals with osteoporosis and other metabolic bone diseases. The objectives of the current study were to develop a mathematical model that simulates control and 1 year experimental results following bisphosphonate treatment (alendronate or risedronate) in the canine fourth lumbar vertebral body, validate the model by comparing simulation predictions to 3 year experimental results, and then use the model to predict potential long term effects of bisphosphonates on remodeling and microdamage accumulation. To investigate the effects of bisphosphonates on bone volume and microdamage, a mechanistic biological model …


The Influence Of Carbon Source Types And Nitrate On The Performance Of The Enhanced Biological Phosphorus Removal Systems, Shamim Ara Begum May 2009

The Influence Of Carbon Source Types And Nitrate On The Performance Of The Enhanced Biological Phosphorus Removal Systems, Shamim Ara Begum

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research focuses on two issues in enhanced biological phosphorus removal (EBPR). The first issue encompasses the effect of the type of carbon sources (i.e. volatile fatty acids and non volatile fatty acids) on the microbiology of EBPR. The second issue deals with the influence of denitrification on EBPR. Few studies have been performed to investigate these two issues. The recent findings on these areas are summarized below to establish the knowledge gaps this dissertation attempted to address. Details on the specific findings can be found in the literature review portion of this proposal.


Design Of A "Figure-8" Spherical Motion Flapping Wing For Miniature Uav's, Zohaib Parvaiz Rehmat May 2009

Design Of A "Figure-8" Spherical Motion Flapping Wing For Miniature Uav's, Zohaib Parvaiz Rehmat

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hummingbirds and some insects exhibit a Figure-8 motion, which allows them to undergo variety of maneuvers including hovering. It is therefore desirable to have flapping wing miniature air vehicles (FWMAV) that can replicate this unique wing motion. In this research, a design of a flapping wing for FWMAV that can mimic Figure-8 motion using a spherical four bar mechanism is presented. To produce Figure-8 motion, the wing is attached to the coupler point of the spherical four bar mechanism and driven by a DC servo motor. For verification of the design, a prototype of the wing and mechanism is fabricated …


Analysis Of Phase Ii Metabolites Of Methamphetamine By Solid-Phase Extraction And Liquid Chromatography With Tandem Mass Spectrometric Detection, Jordan Carbary, Howard P. Hendrickson May 2009

Analysis Of Phase Ii Metabolites Of Methamphetamine By Solid-Phase Extraction And Liquid Chromatography With Tandem Mass Spectrometric Detection, Jordan Carbary, Howard P. Hendrickson

Biological and Agricultural Engineering Undergraduate Honors Theses

Methamphetamine (METH) abuse is one of the most serious health problems in the United States and Europe due to its addictive properties and potential neurotoxic effects [1, 2, 3]. METH abuse appears to have stabilized or decreased slightly in the general populations, however abuse in certain populations is increasing [4, 5]. Treatments for drug abuse are often tested in animal behavioral pharmacology models. One of the first in vivo tests conducted in animals is to follow the concentration of the drug and its metabolites as a function of time. In this way, one can determine how long a potential medication …


Biology-Inspired Adaptive And Nonlinear Robust Control Of Bauv Using Pectoral-Like Fins, Subramanian Ramasamy May 2009

Biology-Inspired Adaptive And Nonlinear Robust Control Of Bauv Using Pectoral-Like Fins, Subramanian Ramasamy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aquatic animals have splendid ability to move smoothly through water using variety of oscillating fins. Presently researchers are involved in developing biorobotic autonomous underwater vehicles (BAUVs) which have the ability to swim like marine animals. Multiple oscillating fins (dorsal, caudal, pectoral, pelvic, etc.) can be mounted on BAUVs to generate control forces for propulsion and maneuvering. In this research work, control of the BAUVs using pectoral fins alone is considered. The oscillating pectoral fins produce unsteady periodic forces. The control of motion of an BAUV in yaw and dive planes are considered.


The I-70 Greenfield Rest Area Wetland Projects, Shih-Chieh Kao, Ting Pong Chang, Rebeka Sultana, Thomas Konopka, Rao S. Govindaraju, Barry Partridge May 2009

The I-70 Greenfield Rest Area Wetland Projects, Shih-Chieh Kao, Ting Pong Chang, Rebeka Sultana, Thomas Konopka, Rao S. Govindaraju, Barry Partridge

JTRP Technical Reports

On-site treatment of wastewater at highway rest areas poses some unique and difficult challenges because of the rural locale, high variability in wastewater flow rate and strength, and lack of knowledgeable personnel on-site. As a potential alternative, a constructed subsurface wetland system was built at the I-70 rest stop nearby Greenfield, Indiana, in 2003. This wetland system, mainly composed of three wetland cells, also includes draw-and-fill and recirculation mechanisms to increase oxygen transfer to the wastewater and improve the overall treatment performance. Special considerations for highway rest areas have been emphasized. A dynamic hydraulic model was developed to help characterize …


Site-Specific Deoxyribonucleic Acid Modifications For Use With Chemical Cages, John P. Casey Jr May 2009

Site-Specific Deoxyribonucleic Acid Modifications For Use With Chemical Cages, John P. Casey Jr

Honors Capstones

No abstract provided.


The Effect Of Hydrostatic Pressure On Bladder Smooth Muscle Cell Function, Margaret Drumm May 2009

The Effect Of Hydrostatic Pressure On Bladder Smooth Muscle Cell Function, Margaret Drumm

All Theses

Previous research has demonstrated that bladder smooth muscle cells (BSMC) respond to various forms of mechanical stimuli, including stretch and hydrostatic pressure, by increases of cell proliferation, activation of intracellular signaling pathways, and alteration of contractile and synthetic marker protein expression. These cellular/molecular level changes are all indicative of a BSMC phenotypic shift that can negatively impact the bladder function at the tissue and organ level. The objective of the present study is to test a hypothesis that bladder SMCs shift their phenotype from contractile to synthetic in response to elevated hydrostatic pressure. Rat bladder SMC cultures were exposed to …


A Pulsatile Bioreactor For Conditioning Tissue Engineered Heart Valves, Leslie Sierad May 2009

A Pulsatile Bioreactor For Conditioning Tissue Engineered Heart Valves, Leslie Sierad

All Theses

Tissue engineered constructs with autologous adult stem cells capable of self-repair and growth are highly desired replacements for diseased heart valves. However, the current approaches have inadequate mechanical properties to withstand in vivo implantation. Therefore, our group hypothesized that an in vitro environment of physiological intra-cardiac pressures and flow will stimulate stem cells to differentiate and remodel valvular scaffold constructs before implantation.
The group developed a pneumatic-driven conditioning system (Aim I) consisting of a three-chambered heart valve bioreactor, a pressurized compliance tank, a reservoir tank, one-way valves, pressure-retaining valves, and pressure transducers. The system can be sterilized using conventional autoclaving …


Development Of An In-Vitro Tissue Engineered Blood Vessel Mimic Using Human Large Vessel Cell Sources, Dimitri E. Delagrammaticas May 2009

Development Of An In-Vitro Tissue Engineered Blood Vessel Mimic Using Human Large Vessel Cell Sources, Dimitri E. Delagrammaticas

Master's Theses

Tissue engineering is an emerging field that offers novel and unmatched potential medical therapies and treatments. While the vast aim of tissue engineering endeavors is to provide clinically implantable constructs, secondary applications have been developed to utilize tissue-engineered constructs for in-vitro evaluation of devices and therapies. Specifically, in-vitro blood vessel mimics (BVM) have been developed to create a bench-top blood vessel model using human cells that can be used to test and evaluate vascular disease treatments and intravascular devices. Previous BVM work has used fat derived human microvascular endothelial cells (EC) sodded on an ePTFE scaffold. To create a more …


Implementation Of Physiologic Flow Conditions In A Blood Vessel Mimic Bioreactor System For The Evaluation Of Intravascular Devices, Marc Cody Dawson May 2009

Implementation Of Physiologic Flow Conditions In A Blood Vessel Mimic Bioreactor System For The Evaluation Of Intravascular Devices, Marc Cody Dawson

Master's Theses

The prevalence and devastating nature of cardiovascular diseases has led to many advancements in the therapies used to treat the millions of patients that suffer as a result of these conditions. As coronary artery disease (CAD) is the most common of these cardiovascular conditions, it is a major focus of research among the medical industry. Although lifestyle changes and drug therapies can treat early CAD, more advanced cases often require more definitive interventions. In conjunction with angioplasty, stenting of an occluded vessel has shown significant success in preventing restenosis. However, as with nearly every therapeutic process in the medical field, …