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Structural Characterization Of Super-Acid Oligomerized Fatty Esters., Esam Allehyani Dec 2013

Structural Characterization Of Super-Acid Oligomerized Fatty Esters., Esam Allehyani

Electronic Theses & Dissertations

Fatty acid methyl esters can be oligomerized with very strong acid catalysts - superacids such as tetrafluoroboric or triflic acid with formation of dimer and trimer fatty acids at much lower temperature, such as 80-90 °C, than what is used presently. Insight into the reaction of polymerization of fatty esters/ acids can be obtained by structural characterization. This would determine the properties of the oligomeric products and their ability to substitute currently used materials. It was presumed that dimer fatty, trimer fatty acid esters, and oligomeric fatty acid esters are produced by polymerization of fatty acid methyl esters by a …


Monodentate, Bidentate And Photocrosslinkable Thiol Ligands For Improving Aqueous Biocompatible Quantum Dots, Hiroko Takeuchi Dec 2013

Monodentate, Bidentate And Photocrosslinkable Thiol Ligands For Improving Aqueous Biocompatible Quantum Dots, Hiroko Takeuchi

Graduate Theses and Dissertations

Water-soluble Quantum Dots (QDs) are highly sensitive fluorescent probes that are often used to study biological species. One of the most common ways to render QDs water-soluble for such applications is to apply hydrophilic thiolated ligands to the QD surface. However, these ligands are labile and can be easily exchanged on the QD surface, which can severely limit their application. As one way to overcome this limitation while maintaining a small colloidal size of QDs, we developed a method to stabilize hydrophilic thiolated ligands on the surface of QDs through the formation of a crosslinked shell using a photocrosslinking approach. …


Research: South Dakota State University, Winter 2013, Christie Delfanian, Matt Landwehr Dec 2013

Research: South Dakota State University, Winter 2013, Christie Delfanian, Matt Landwehr

State of Discovery South Dakota State University's Research Magazine

CONTENTS:

South Dakota expertise integral part of Landsat [Page] 1
West Nile: Researchers help public health officials combat West Nile virus [page] 2
Health care: arteries, corticosteroids, concussions, and preemies [Page] 4
Oilseeds [Page] 6
Undergraduate Research [Page] 8
Organ donation key to helping Native Americans on dialysis [Page] 10
Researchers meet challenge of increased competition: 2012 measurements [Page] 11


Sodhana Environmental - Final Design Report, Eric Taylor, Corissa Bellis, Cody Perez, Cameron Zeller Dec 2013

Sodhana Environmental - Final Design Report, Eric Taylor, Corissa Bellis, Cody Perez, Cameron Zeller

Mechanical Engineering

A fully designed cost-effective, sustainable, toilet for the developing world.


Fracture Toughness Of A Hyperelastic Material During Surgical Cutting, Kevin Smith Dec 2013

Fracture Toughness Of A Hyperelastic Material During Surgical Cutting, Kevin Smith

HIM 1990-2015

Despite being one of the most important organs of vertebrates, the material properties of skin are also one of the most poorly understood. In the field of designing medical devices and surgical tools there are significant advantages to having a model that describes the interaction of forces between a blade tip and skin during surgical cutting. In general, skin can best be described as a composite layer consisting of a viscoelastic dermis with interwoven collagen and elastin fibers beneath a superficial epidermis. The purpose of this research is to study the fracture toughness of porcine skin during practical cutting applications, …


Development And Validation Of An Absorption Sensor For Time-Resolved Measurements Of Co And Co2, Kyle Thurmond Dec 2013

Development And Validation Of An Absorption Sensor For Time-Resolved Measurements Of Co And Co2, Kyle Thurmond

HIM 1990-2015

A sensor was developed for simultaneous measurements of carbon monoxide and carbon dioxide fluctuations in internal combustion engine exhaust gases. This sensor utilizes low-cost and compact LEDs that emit in the 3-5[micro]m wavelength range which are more appropriate for practical applications than the more traditionally used lasers. An affordable, fast response sensor that can measure these gases has broad application that can lead to more efficient, fuel flexible engines and regulations of harmful emissions. LEDs have a more spectrally broad and diverging emission than lasers which presented many design challenges. The optical design software ZEMAX was utilized to overcome these …


Water Fat Separation With Multiple-Acquisition Balanced Steady-State Free Precession Mri, Michael A. Mendoza Dec 2013

Water Fat Separation With Multiple-Acquisition Balanced Steady-State Free Precession Mri, Michael A. Mendoza

Theses and Dissertations

Magnetic resonance imaging (MRI) is an important medical imaging technique for visualizing soft tissue structures in the body. It has the advantages of being noninvasive and, unlike x-ray, does not rely on ionizing radiation for imaging. In traditional hydrogen-based MRI, the strongest measured signals are generated from the hydrogen nuclei contained in water and fat molecules.Reliable and uniform water fat separation can be used to improve medical diagnosis. In many applications the water component is the primary signal of interest, while the fat component represents a signal which can obscure the underlying pathology or other features of interest. In other …


Characterization And Processing Evaluation Of Starch/High-Density Polyethylene Materials In Extrusion Blow Molding, Bradley Dale Bacigalupi Dec 2013

Characterization And Processing Evaluation Of Starch/High-Density Polyethylene Materials In Extrusion Blow Molding, Bradley Dale Bacigalupi

Theses and Dissertations

The growing negative impacts of non-biodegradable plastics derived from non-renewable materials have created increasing interest throughout the world for new materials that are both biodegradable and renewable, that can be combined with or replace traditional plastics. Plant-based thermoplastic starch (TPS), a promising alternative material to traditional petroleum based resin, is both biodegradable and renewable and has great potential for use in plastic manufacturing processes. Two major obstacles that prevent more widespread use of TPS include; TPS base material, which is typically manufactured in a flake or powder, is incompatible with standard plastics production equipment that require pelletized resin, the second …


Development And Evaluation If Best Management Practices For Highway Runoff Pollution Control, Tian C. Zhang, John S. Stansbury, Massom Moussavi Dec 2013

Development And Evaluation If Best Management Practices For Highway Runoff Pollution Control, Tian C. Zhang, John S. Stansbury, Massom Moussavi

Nebraska Department of Transportation: Research Reports

No abstract provided.


In Vitro Simulation Of Pathological Bone Conditions To Predict Clinical Outcome Of Bone Tissue Engineered Materials, Duong Nguyen Dec 2013

In Vitro Simulation Of Pathological Bone Conditions To Predict Clinical Outcome Of Bone Tissue Engineered Materials, Duong Nguyen

All Dissertations

According to the Centers for Disease Control, the geriatric population of ≥65 years of age will increase to 51.5 million in 2020; 40% of white women and 13% of white men will be at risk for fragility fractures or fractures sustained under normal stress and loading conditions due to bone disease, leading to hospitalization and surgical treatment. Fracture management strategies can be divided into pharmaceutical therapy, surgical intervention, and tissue regeneration for fracture prevention, fracture stabilization, and fracture site regeneration, respectively. However, these strategies fail to accommodate the pathological nature of fragility fractures, leading to unwanted side effects, implant failures, …


Biogeochemical Modeling Of The Response Of Forest Watersheds In The Northeastern U.S. To Future Climate Change, Afshin Pourmokhtarian Dec 2013

Biogeochemical Modeling Of The Response Of Forest Watersheds In The Northeastern U.S. To Future Climate Change, Afshin Pourmokhtarian

Dissertations - ALL

In this dissertation I assessed the potential hydrochemical responses of future climate change conditions on forested watersheds in the northeastern U.S. using climate projections from several atmosphere ocean general circulation models (AOGCMs) under different carbon dioxide (CO2) emissions scenarios. The impacts of changing climate on terrestrial ecosystems have been assessed by observational, gradient, laboratory and field studies; however, state-of-the-art biogeochemical models provide an excellent tool to investigate climatic perturbations to these complex ecosystems. The overarching goal of this dissertation was to apply a fully integrated coupled hydrological and biogeochemical model (PnET-BGC) to evaluate the effects of climate change and increasing …


An Investigation Into The Water Budget And The Management Of The Snake River System, John Whitney Hildreth Dec 2013

An Investigation Into The Water Budget And The Management Of The Snake River System, John Whitney Hildreth

Boise State University Theses and Dissertations

Future climate change poses a major conceptual challenge to the availability of water resources due to the uncertainty involved with changes to the hydrologic cycle. Over the past decades, observed warming temperatures across the Western United Sates have shown significant impacts on river basin scale hydrology. This research uses physically based modeling tools to assess the hydrologic impacts of climate change in the Snake River Basin. Physically based hydrologic modeling studies of future climate do not typically take into account interactions between groundwater and surface water. To account for these interactions, the Variable Infiltration Capacity model is coupled with the …


Mass Production Of Β-Silicon Carbide Nanofibers By The Novel Method Of Forcespinning, Alfonso Salinas Dec 2013

Mass Production Of Β-Silicon Carbide Nanofibers By The Novel Method Of Forcespinning, Alfonso Salinas

Theses and Dissertations - UTB/UTPA

Non-oxide Ceramics such as silicon carbide have very unique properties, for example high toughness, thermal stability, wear resistant, and thermal shock resistance these properties make these ceramic fibers excellent for high temperature applications. Here we present the development of Silicon Carbide nanofibers utilizing a Polystyrene/Polycarbomethylsilane solution as the precursor materials. The Forcespinning ® was performed under a controlled nitrogen environment to prevent fiber oxidation. Characterization was conducted using scanning electron microscopy, x-ray diffraction, and thermogravimetric analysis. The results show successful formation of high yield, long continuous bead-free nanofibers with diameters ranging from 280nm to 2 micron depending on the selected …


Instrumentation Electronics For An Integrated Electrophysiology Data Acquisition And Stimulation System, Donovan Squires Dec 2013

Instrumentation Electronics For An Integrated Electrophysiology Data Acquisition And Stimulation System, Donovan Squires

Masters Theses

The Neurobiology Engineering Laboratory at Western Michigan University has need of an electrophysiology instrumentation system combining generation of multiple arbitrary stimulation waveforms and recording of action potentials on multiple channels. Electronics for an instrumentation system with the capability of generating four unique stimulation waveforms and recording action potentials on eight channels were developed and implemented on a printed circuit board. Collaboration with fellow graduate student, Mr. Kyle Batzer, who developed firmware and software for the instrumentation system as described in his thesis, was essential for successful realization of the instrumentation system. Knowledge gained and reported by previous students working in …


Firmware And Software For An Integrated Electrophysiology Data Acquisition And Stimulation System, Kyle D. Batzer Dec 2013

Firmware And Software For An Integrated Electrophysiology Data Acquisition And Stimulation System, Kyle D. Batzer

Masters Theses

This thesis describes the firmware and software design for a prototype electrophysiology experimentation system. The overall system, built on the work of previous students and developed with fellow graduate student Mr. Donovan Squires, provides eight channels of acquisition and four channel of arbitrary waveform generation for stimulation of biological systems. In order to show the performance of the system, a common electrophysiology experiment was performed on the giant axon of an earthworm and the results were compared to previously validated systems. The developed system is intended to support future work at the Neurobiology Engineering Laboratory at Western Michigan University.

The …


Reassessment Of Biowish Activation Procedure For Denitrification, William Wah Yee Dec 2013

Reassessment Of Biowish Activation Procedure For Denitrification, William Wah Yee

Master's Theses

BiOWiSHTM – Aqua is a blend of preserved multi-bacteria culture with the capability of denitrification. If an anaerobic nitrate rich activation procedure is used instead of the standard aerobic activation procedure, the denitrification rate is increased by 28 percent under the conditions of 30°C, 1C:1N, 200mg/L of carbon, and 200mg/L nitrogen.


Lipid Production By Microalgae Treating Municipal Wastewater, James Edward Kelley Dec 2013

Lipid Production By Microalgae Treating Municipal Wastewater, James Edward Kelley

Master's Theses

Microalgae hold much promise as a feedstock in liquid biofuel production. Lipid content of microalgae cells range from 30-80% dry weight of biomass. It is projected that microalgae can produce between 1,000-6,500 gallons/acre/year of oil. Currently, production of industrial algae operates in open raceway ponds that use minimal capital and energy inputs to culture algae. Raceway ponds can also be used to grow microalgae from municipal waste streams. Although high biomass productivity can be achieved in these systems, there remains a large production gap between large volumes of biomass cultivation and high lipid content from microalgae cells. Low lipid content …


Development And Validation Of A Human Hip Joint Finite Element Model For Tissue Stress And Strain Predictions During Gait, Jeffrey D. Pyle Dec 2013

Development And Validation Of A Human Hip Joint Finite Element Model For Tissue Stress And Strain Predictions During Gait, Jeffrey D. Pyle

Master's Theses

Articular cartilage degeneration, called osteoarthritis, in the hip joint is a serious condition that affects millions of individuals yearly, with limited clinical solutions available to prevent or slow progression of damage. Additionally, the effects of high-risk factors (e.g. obesity, soft and hard tissue injuries, abnormal joint alignment, amputations) on the progression of osteoarthritis are not fully understood. Therefore, the objective of this thesis is to generate a finite element model for predicting osteochondral tissue stress and strain in the human hip joint during gait, with a future goal of using this model in clinically relevant studies aimed at prevention, treatment, …


Mechanical Properties Of Bone Due To Sost Expression: Nanoindentation Assessment Of Murine Femurs, Amir Rafie Dec 2013

Mechanical Properties Of Bone Due To Sost Expression: Nanoindentation Assessment Of Murine Femurs, Amir Rafie

Master's Theses

In the human genome, the SOST gene codes for a protein sclerostin. Sclerostin is an osteocyte-expressed negative regulator of bone formation. When the SOST gene is not coded, bone formation is reduced in individuals during skeletal maturation. This study utilizes nanoindentation methods to test for the mechanical properties of bones that both express and do not express the SOST gene. 100 transgenic murine femurs were obtained from Lawrence Livermore Labs in the form of 6 and 8 month SOST transgenic mice, 6 and 12 month SOST knockout mice, and wild type control littermates for each of the 4 age groups. …


Synthesis And Characterization Of Polymer Layers For Control Of Fluid Transport, Fehime Vatansever Dec 2013

Synthesis And Characterization Of Polymer Layers For Control Of Fluid Transport, Fehime Vatansever

All Dissertations

The level of wetting of fiber surface with liquids is an important characteristic of fibrous materials. It is related to fiber surface energy and the structure of the material. Surface energy can be changed by surface modification via the grafting methodologies that have been reported for introducing new and stable functionality to fibrous substrates without changing bulk properties.

Present work is dedicated to synthesis and characterization of macromolecular layers grafted to fiber surface in order to achieve directional liquid transport for the modified fabric. Modification technique used here is based on formation of stable polymer layer on fabric surface using …


Vascular Nanomedicine: Site Specific Delivery Of Elastin Stabilizing Therapeutics To Damaged Arteries, Aditi Sinha Dec 2013

Vascular Nanomedicine: Site Specific Delivery Of Elastin Stabilizing Therapeutics To Damaged Arteries, Aditi Sinha

All Dissertations

Elastin, a structural protein in the extra-cellular matrix, plays a critical role in the normal functioning of blood vessels. Apart from performing its primary function of providing resilience to arteries, it also plays major role in regulating cell-cell and cell-matrix interactions, response to injury, and morphogenesis. Medial arterial calcification (MAC) and abdominal aortic aneurysm (AAA) are two diseases where the structural and functional integrity of elastin is severely compromised. Although the clinical presentation of MAC and AAA differ, they have one common underlying causative mechanism--pathological degradation of elastin. Hence prevention of elastin degradation in the early stages of MAC and …


Biological Scaffolds For Peripheral Vascular Surgery, George Fercana Dec 2013

Biological Scaffolds For Peripheral Vascular Surgery, George Fercana

All Dissertations

The gold standards for small diameter peripheral vascular graft replacement are autologous arteries or veins; however, one-third of patients lack such vessels due to previous vessel harvesting or advanced vascular disease. A promising approach for patients in this category is tissue engineering with off-the-shelf biological vascular grafts. Three small diameter acellular scaffolds were developed and evaluated as vascular grafts. Porcine renal arteries (2-3 mm diameter, 20 mm length) were decellularized by immersion and stabilized with penta-galloyl glucose (PGG) with and without subsequent heparinization via carbodiimide chemistry. Bovine mammary (4-6 mm ID, 250 mm length) and femoral arteries (6-8 mm ID, …


Exploring Multiple Levels Of Performance Modeling For Heterogeneous Systems, Venkittaraman Vivek Pallipuram Krishnamani Dec 2013

Exploring Multiple Levels Of Performance Modeling For Heterogeneous Systems, Venkittaraman Vivek Pallipuram Krishnamani

All Dissertations

The current trend in High-Performance Computing (HPC) is to extract concurrency from clusters that include heterogeneous resources such as General Purpose Graphical Processing Units (GPGPUs) and Field Programmable Gate Array (FPGAs). Although these heterogeneous systems can provide substantial performance for massively parallel applications, much of the available computing resources are often under-utilized due to inefficient application mapping, load balancing, and tuning. While several performance prediction models exist to efficiently tune applications, they often require significant computing architecture knowledge for reliable prediction. In addition, they do not address multiple levels of design space abstraction and it is often difficult to choose …


Design And Synthesis Of Polymer - Magnetic Nanoparticle Composites For Use In Biomedical Applications, Roland Stone Dec 2013

Design And Synthesis Of Polymer - Magnetic Nanoparticle Composites For Use In Biomedical Applications, Roland Stone

All Dissertations

The future of diagnostics and therapeutic drugs in biomedicine is nanoparticles. These nanoparticles come in many different shapes, sizes, and combination of materials. Magnetic nanoparticles have been studied for many years for use in biomedicine, not only for their high surface area, but also because of its unique magnetic properties. They can magnetically interact with their environment, be guided to a specific location, and manipulated to release energy in the form of heat. To ensure that these magnetic nanoparticles survive in the circulatory system, they must be modified with materials to make them colloidally stable in water and shield them …


Depleted Energy Charge And Increased Pulmonary Endothelial Permeability Induced By Mitochondrial Complex I Inhibition Are Mitigated By Coenzyme Q1 In The Isolated Perfused Rat Lung, Robert D. Bongard, Ke Yan, Raymond G. Hoffmann, Said H. Audi, Xiao Zhang, Brian J. Lindemer, Mary I. Townsley, Marilyn P. Merker Dec 2013

Depleted Energy Charge And Increased Pulmonary Endothelial Permeability Induced By Mitochondrial Complex I Inhibition Are Mitigated By Coenzyme Q1 In The Isolated Perfused Rat Lung, Robert D. Bongard, Ke Yan, Raymond G. Hoffmann, Said H. Audi, Xiao Zhang, Brian J. Lindemer, Mary I. Townsley, Marilyn P. Merker

Biomedical Engineering Faculty Research and Publications

Mitochondrial dysfunction is associated with various forms of lung injury and disease that also involve alterations in pulmonary endothelial permeability, but the relationship, if any, between the two is not well understood. This question was addressed by perfusing isolated intact rat lung with a buffered physiological saline solution in the absence or presence of the mitochondrial complex I inhibitor rotenone (20 μM). Compared to control, rotenone depressed whole lung tissue ATP from 5.66±0.46 (SEM) to 2.34±0.15 µmol·g−1 dry lung, with concomitant increases in the ADP:ATP and AMP:ATP ratios. Rotenone also increased lung perfusate lactate (from 12.36±1.64 to 38.62±3.14 µmol·15 …


Computer Self-Efficacy, Cognitive Actions, And Metacognitive Strategies Of High School Students While Engaged In Interactive Learning Modules, Harry Budi Santoso Dec 2013

Computer Self-Efficacy, Cognitive Actions, And Metacognitive Strategies Of High School Students While Engaged In Interactive Learning Modules, Harry Budi Santoso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to investigate high school students’ computer self-efficacy, cognitive actions, and metacognitive strategies in a self-regulated learning (SRL) framework while utilizing an interactive learning module. The researcher hypothesized that computer self-efficacy is correlated positively with cognitive actions and metacognitive strategies while the students are engaged with interactive learning modules. This research used a mixed-methods approach to answer the research questions. Two research questions guided this research: (1) How is students’ computer self-efficacy related to cognitive actions and metacognitive strategies while using interactive learning modules?; and (2) How do students plan monitor their cognitive actions, and …


Synthesis And Characterization Of Multi-Component Enrichment Polymer Layers For Chemical Sensor Applications, James Giammarco Dec 2013

Synthesis And Characterization Of Multi-Component Enrichment Polymer Layers For Chemical Sensor Applications, James Giammarco

All Dissertations

This dissertation presents the building and study of a "universal" enrichment polymer layer system (EPLS). Thin polymer films have been utilized as enrichment layers for evanescent waveguide chemical sensors. The chemical nature of the polymer provides affinity which promotes the analyte to be absorbed. Having one highly sensitive polymer layer is suitable for a single target volatile organic compound (VOC). Here, the development of multi-layered and multi-component thin polymer films has been done to allow for more diverse affinity. Several parameters were identified to make the EPLSs suitable as enrichment layers for chemical sensor devices. The evanescent sensor devices used …


Identification Of Novel Genes Regulating Elastic Fiber Formation Through Expression Profiling Analysis Of Elastogenic Models, Erin Sproul Dec 2013

Identification Of Novel Genes Regulating Elastic Fiber Formation Through Expression Profiling Analysis Of Elastogenic Models, Erin Sproul

All Dissertations

Background: Particularly important to the mechanical performance of native arterial blood vessels is elastin, an extracellular matrix (ECM) protein deposited by VSMCs in the form of elastic fibers, arranged in concentric lamellae in the media of the vessel wall. In addition to serving as major structural elements of arterial walls, providing extensibility and elastic recoil, elastic fibers also influence vascular cell behaviors. For these reasons tissue engineers are attempting to exploit elastic fiber biology to enhance vascular graft design and patency. Therefore, developing a greater understanding of the molecular mechanisms of elastogenesis may offer opportunities to control elastogenesis in tissue …


Engineering Beta-Cell Spheroids For Type 1 Diabetes Treatment, Xiaoyan Liu Dec 2013

Engineering Beta-Cell Spheroids For Type 1 Diabetes Treatment, Xiaoyan Liu

All Dissertations

Diabetes mellitus, the third most common disease in the world, is a chronic metabolic disorder caused by a failure of insulin production and/or an inability to respond to insulin. Specifically, type 1 diabetes is a disorder characterized by targeted autoimmune-directed destruction of a patient's beta-cell population within the pancreatic islets of Langerhans. The current primary treatment for type 1 diabetes is daily multiple insulin injections. However, this treatment cannot provide sustained physiological release, and the insulin amount is not finely tuned to glycemia. Pancreatic transplants or islet transplants would be the preferred treatment method but the lack of donor tissue …


Aerodynamic Performance And Particle Image Velocimetery Of Piezo Actuated Biomimetic Manduca Sexta Engineered Wings Towards The Design And Application Of A Flapping Wing Flight Vehicle, Anthony M. Deluca Dec 2013

Aerodynamic Performance And Particle Image Velocimetery Of Piezo Actuated Biomimetic Manduca Sexta Engineered Wings Towards The Design And Application Of A Flapping Wing Flight Vehicle, Anthony M. Deluca

Theses and Dissertations

Considerable research and investigation has been conducted on the aerodynamic performance, and the predominate flow physics of the Manduca sexta size of biomimetically designed and fabricated wings as part of the AFIT FWMAV design project. Despite a burgeoning interest and research into the diverse field of flapping wing flight and biomimicry, the aerodynamics of flapping wing flight remains a nebulous field of science with considerable variance into the theoretical abstractions surrounding aerodynamic mechanisms responsible for aerial performance. Traditional FWMAV flight models assume a form of a quasi-steady approximation of wing aerodynamics based on an infinite wing element model (BEM). An …