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Multifunctional Nanophosphors For Tissue Imaging And Drug Delivery, Hongyu Chen May 2013

Multifunctional Nanophosphors For Tissue Imaging And Drug Delivery, Hongyu Chen

All Dissertations

X-rays have been used for non-invasive high-resolution imaging of thick biological specimens since their discovery in 1895. They are widely used for structural imaging of bone, metal implants, and cavities in soft tissue. Recently, a number of new contrast methodologies have emerged which are expanding X-ray's biomedical applications to functional as well as structural imaging. However, traditional X-ray imaging provides high spatial resolution imaging through tissue but do not measure chemical concentrations. In this dissertation, we describe an X-ray excited optical luminescence (XEOL) technique which uses a scanning X-ray beam to irradiate Gd2O2S phosphors and detect the resulting visible luminescence …


Aerosol Delivery As A Method For Enhancing Remedial Application In Contaminated Vadose Zones, Richard Hall May 2013

Aerosol Delivery As A Method For Enhancing Remedial Application In Contaminated Vadose Zones, Richard Hall

All Dissertations

Remediation of contaminated vadose zones is often hindered by an inability to effectively distribute liquid- or solid-phase amendments. Many amendment-based approaches, such as bioremediation, chemical oxidation, and reactive barriers have been successful in saturated formations. However, these remedial approaches have seen limited application in unsaturated materials, largely because of difficulties delivering amendments.
Aerosol delivery is a promising approach for distributing amendments in contaminated vadose zones. The amendments are aerosolized, creating a cloud of micron to sub-micron-scale liquid droplets held suspended in a gas by Brownian motion. During injection into porous media, the aerosol particles are transported along with the gas …


Highly Sensitive Fiber-Based Devices For Gene And Protein Analysis, Victor Maximov May 2013

Highly Sensitive Fiber-Based Devices For Gene And Protein Analysis, Victor Maximov

All Dissertations

Single cell probing has found a number of applications in different areas of research. It can help us to better understand cell-to-cell interactions; it has found numerous applications in immunology, cancer research, detection of pathogenic infections and genetic abnormalities. The single cell analysis is very important in stem cells research and development of cells. The main obstacle in the single cell analysis is the small amount of analyte that a single cell could provide. Another difficulty is connected to the cell-to-cell variability inside the uniform population due to the differences of single cells in size, activity, mitotic stage, and functions. …


Biomarkers Of Fatigue: Metabolomics Profiles Predictive Of Cognitive Performance, Nicholas J. Delraso, Deirdre A. Mahle, John J. Schlager, Donald L. Harville, Scott R. Chaiken, Danelle K. Roddy, Mari Chamberlain, Paul E. Anderson, Nicholas V. Reo, Michael L. Raymer, Isaie Sibomana May 2013

Biomarkers Of Fatigue: Metabolomics Profiles Predictive Of Cognitive Performance, Nicholas J. Delraso, Deirdre A. Mahle, John J. Schlager, Donald L. Harville, Scott R. Chaiken, Danelle K. Roddy, Mari Chamberlain, Paul E. Anderson, Nicholas V. Reo, Michael L. Raymer, Isaie Sibomana

Computer Science and Engineering Faculty Publications

Cognitive performance and fatigue are well known to be inversely related. Continuous and sustained actions in operational environments typically lead to reduced sleep normally required to perform optimally. These operational environments subject the warfighter to intense physical and mental exertion. Because fatigue continues to be an occupational hazard, leading to cognitive defects in performance, there has been a recognized need for real-time detection technologies that minimize fatigue-induced mishaps. I the current study, 23 subjects were subjected to 36h of sleep deprivation and cognitive psychomotor vigilance and automated neuropsychological assessment metric tests were conducted over the last 24 h of sleep …


A Gamos Plug-In For Geant4 Based Monte Carlo Simulation Of Radiation-Induced Light Transport In Biological Media, Adam K. Glaser, Stephen C. Kanick, Rongxiao Zhang, Pedro Arce, Brian W. Pogue May 2013

A Gamos Plug-In For Geant4 Based Monte Carlo Simulation Of Radiation-Induced Light Transport In Biological Media, Adam K. Glaser, Stephen C. Kanick, Rongxiao Zhang, Pedro Arce, Brian W. Pogue

Dartmouth Scholarship

We describe a tissue optics plug-in that interfaces with the GEANT4/GAMOS Monte Carlo (MC) architecture, providing a means of simulating radiation-induced light transport in biological media for the first time. Specifically, we focus on the simulation of light transport due to the Čerenkov effect (light emission from charged particle's traveling faster than the local speed of light in a given medium), a phenomenon which requires accurate modeling of both the high energy particle and subsequent optical photon transport, a dynamic coupled process that is not well-described by any current MC framework. The results of validation simulations show excellent agreement with …


A Preliminary Discourse On Adhesion Of Nanofibers Derived From Electrospun Polymers, Pei Chen May 2013

A Preliminary Discourse On Adhesion Of Nanofibers Derived From Electrospun Polymers, Pei Chen

Mechanical Engineering Faculty Research

To bio-mimic gecko’s foot hair, which possess high adhesion strength and can be re- usable for lifetime, fibrous membranes are fabricated by electrospinning to provide sufficient adhesion energy. Shaft-loaded blister test (SLBT) is firstly used to measure the work of adhesion between electrospun membrane and rigid substrate. Poly(vinylidene fluoride) (PVDF) were electrospun with an average fiber diameter of 333±59 nm. Commercial cardboard with inorganic coating was used to provide a model substrate for adhesion tests. In SLBT, the elastic response PVDF was analyzed and its adhesion energy measured. FEA model with cohesive layer is developed to evaluate the experiment results. …


Friends Of The Lester F. Larsen Tractor Test & Power Museum Newsletter, Spring 2013 May 2013

Friends Of The Lester F. Larsen Tractor Test & Power Museum Newsletter, Spring 2013

Friends of the Larsen Tractor Museum

Membership renewal

Annual Meeting, May 17, 2013

Honoring William E. Splinter


Stormwater Pollution Treatment Bmp Discharge Structures, Miles F. Simmons May 2013

Stormwater Pollution Treatment Bmp Discharge Structures, Miles F. Simmons

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Structural best management practices (BMPs) are used to capture and treat stormwater runoff. Most structural BMPs provide treatment by filtering runoff through a filter media or collecting it in a detention basin and slowly discharging it over an extended period of time to allow suspended solids and associated contaminants to settle out. The purpose of this study is to design an effective outlet structure that provides adequate filtration or slows discharge to 40 hours.

A model detention basin was constructed in the Civil Engineering Hydraulics Laboratory at the University of Nebraska-Lincoln (UNL) and two full scale outlet structures were tested …


Controlling Bacterial Persister Cells With Low Level Electric Currents, Henry Lars Peterson May 2013

Controlling Bacterial Persister Cells With Low Level Electric Currents, Henry Lars Peterson

Renée Crown University Honors Thesis Projects - All

Bacterial persister cells present a growing concern as they inherit the ability to tolerate high concentrations of antibiotics and repopulate after an antibiotic treatment leading to chronic diseases. Pseudomonas aeruginosa causes many human infections including skin infections and those associated with burn injuries, and implanted medical devices, and are associated with Cystic Fibrosis. Recently, the Ren Lab developed a novel approach to eliminate persister cells of P. aeruginosa, including those in biofilms, using low level electric currents. To evaluate the safety of this method and to better understand how the underlying elements, this study focused on the cytotoxicity of …


A Methodology For Designing Pervious Bicycle Lanes For Stormwater Management, Donald West Iii May 2013

A Methodology For Designing Pervious Bicycle Lanes For Stormwater Management, Donald West Iii

All Theses

Bicycles have proven to be an efficient and reliable form of transportation in urban settings. Therefore, the addition of bicycle lanes into the transportation network could significantly impact and improve the sustainability of our infrastructure by reducing greenhouse emissions and improving the health of individuals who cycle on a regular basis. Pervious pavements are an approved (LID) strategy that could potentially be used to construct these new facilities thereby reducing the quantity of stormwater runoff and improving the water quality. Practicing engineers need both a design aid and research supported methods for designing these improvements before they can be fully …


Post-Market Surveillance Of Total Knee Replacement Combining Clinical Outcomes And Quantitative Image Processing Techniques, Leah Nunez May 2013

Post-Market Surveillance Of Total Knee Replacement Combining Clinical Outcomes And Quantitative Image Processing Techniques, Leah Nunez

All Theses

Total knee replacement (TKR) is a successful procedure for the relief of pain, correction of deformity, and restoration of function in patients with knee arthritis.1-3 In the United States, the number of primary TKR surgeries performed in 2030 is projected to be between 2,938,000 to 4,136,000 and revision surgeries between 193,000 to 381,000.4 Osteolysis, pain, and aseptic loosening are the most common causes of revision TKR surgery.5 The purpose of this thesis is to complete assessments for post-market surveillance of total knee replacement (TKR) targeting areas for improving polymer bearings through evaluation of clinical outcomes and analysis of prosthesis retrieved …


Development Of An Ex Vivo Tissue Testing System For Three Dimensional Biomechanical Analysis Of Abdominal Aortic Aneurysm, Bradley Johns May 2013

Development Of An Ex Vivo Tissue Testing System For Three Dimensional Biomechanical Analysis Of Abdominal Aortic Aneurysm, Bradley Johns

All Theses

Abdominal aortic aneurysms (AAA) are localized, progressive dilations of the aortic wall and are the 13th most common cause of death in the United States (~15,000 per year) and surgery is usually recommended when the aneurysm is 5 cm or larger in diameter. Because of this clinical parameter, previous studies of AAA biomechanics have utilized a one-dimensional analysis that focuses solely on changes in wall diameter and have attempted to model geometric changes with mathematical formulas, generally based on the LaPlace equation. This is not sufficient however, as the mechanical behavior of the tissue at sites of aneurysm have been …


Evaluating Mechanical Performance Of Hydrogel-Based Adhesives For Soft Tissue Applications, Nitin Balakrishnan May 2013

Evaluating Mechanical Performance Of Hydrogel-Based Adhesives For Soft Tissue Applications, Nitin Balakrishnan

All Theses

According to the National Center for Health Statistics, an estimated 22 million women have undergone a hysterectomy procedure in the United States. The most common complication during hysterectomies is accidental laceration of the urinary bladder during the surgery with incidence between 0.2-8.3% with the current gold standard wound repair method being sutures. Yet, sutures come with their own limitations in that they necessitate use of a catheter and collection bag during healing due to preventing proper distention of the bladder tissue at normal pressures. The long-term goal of our study is to eliminate the need for suturing by creating a …


Measuring Arousal Through Physiological Responses To Packaging Designs: Investigating The Validity Of Electrodermal Activity As A Measure Of Arousal In A Realistic Shopping Environment, Daniel Hutcherson May 2013

Measuring Arousal Through Physiological Responses To Packaging Designs: Investigating The Validity Of Electrodermal Activity As A Measure Of Arousal In A Realistic Shopping Environment, Daniel Hutcherson

All Theses

The validity of electrodermal activity is investigated in the context of packaging design evaluation as a sensitive measure of arousal. Analysts agree that purchasing decisions are subconscious and emotional decisions, contrasted against the popular belief that consumers make purely rational decisions. To understand the personal and rapid character of a consumer's purchasing decisions we must find methods of which to measure and interpret consumer reactions to various packaging designs. Focus groups are discussed as antiquated research methods and new, advanced technologies are outlined as physiological responses. Past literature displays methodological approaches to using electrodermal activity measures in consumer studies, however …


Noise-Insensitive Prognostic Evaluation Of Historic Masonry Structures, Ashley Haydock May 2013

Noise-Insensitive Prognostic Evaluation Of Historic Masonry Structures, Ashley Haydock

All Theses

In recent years, a significant amount of research has been directed towards the development of prognostic methodologies to forecast the future health state of an engineering system assisting condition based maintenance. These prognostic methods, having furthered the maintenance practices for mechanical systems, have yet to be applied to historic masonry structures, many of which stand in an aged and degraded state. Implementation of prognostic methodologies to historic masonry structures can advance the planning of successful conservation and restoration efforts, ultimately prolonging the life of these heritage structures. This thesis presents a review of prognostic concepts and techniques available in the …


Dynamic Transcriptional Response Of Escherichia Coli To Inclusion Body Formation, Faraz Baig May 2013

Dynamic Transcriptional Response Of Escherichia Coli To Inclusion Body Formation, Faraz Baig

All Theses

Escherichia coli is used intensively for recombinant protein production due to its many unique advantages, but one key challenge with the use of E. coli is the tendency of recombinant proteins to misfold and aggregate into insoluble inclusion bodies (IBs). The presence of IBs stresses cells and can hinder overall growth. Additionally, IBs contain high concentrations of recombinant protein in an inactive form and thus require recovery steps to salvage functional recombinant protein. Currently, no universally effective method exists to prevent IB formation in recombinant E. coli. Further research into the gene expression response to insoluble recombinant protein may …


Evaluation Of Angular Velocity Data From Inertial Measurement Units For Use In Clinical Settings, Chelsea Ex-Lubeskie May 2013

Evaluation Of Angular Velocity Data From Inertial Measurement Units For Use In Clinical Settings, Chelsea Ex-Lubeskie

All Theses

Evaluating the human gait cycle with inertial measurement units (IMU) may prove beneficial for applications such as diagnoses of musculoskeletal diseases and assessment of rehabilitation regimes. An IMU system is potentially applicable for diagnosing and assessing rehabilitation outcomes for a variety of neuromuscular diseases since it is small, portable, and less expensive than a camera system. IMUs directly measure angular velocity, whereas position data from a camera system must be processed twice to obtain this information. The purpose of this research is to determine repeatability of IMU angular velocity data, and agreement between angular velocity data from an IMU system …


A Regenerative Medicine Approach To Improved Tendon Healing And Repair, Grace Margaret Dion May 2013

A Regenerative Medicine Approach To Improved Tendon Healing And Repair, Grace Margaret Dion

All Theses

Surgical repair of torn tendons is a common orthopaedic procedure in the United States, with nearly 400,000 repairs occurring annually. Despite improvements in surgical techniques used to re-attach the tendon to its boney insertion, clinically successful outcomes amongst patients are variable and re-tear rates can be exceedingly high. The use of stem cells as an adjunct to surgical repair to aid in improving tendon healing and repair strength has gained much interest amongst the clinical community. Accordingly, many investigators have begun examining the ability of stem cells to differentiate into tenocytes using various methodologies including the application of growth factors …


Characterization Of Potential Wear Sources In Knee Arthroplasty Prostheses After In Vivo Function, Nicole Durig May 2013

Characterization Of Potential Wear Sources In Knee Arthroplasty Prostheses After In Vivo Function, Nicole Durig

All Theses

Total joint arthroplasty (TJA) is a common procedure generally performed in patients with osteoarthritis. While TJA continues to be a successful treatment for degenerative joint disease, there are many studies that demonstrate wear and its sequelae as the major limitation of joint replacement longevity. Previous studies have shown that wear debris originates from four main locations: articulating surfaces, modular component surfaces, surfaces of fixation, and adjuvant fixation devices. Each of these possible wear sources can initiate the cascade of failure associated with wear-induced osteolysis and lead to subsequent revision surgery. The objective of this thesis is to characterize the in …


Biohydrogen Production By Thermotoga Neapolitana In Agricultural Media, David Morris May 2013

Biohydrogen Production By Thermotoga Neapolitana In Agricultural Media, David Morris

All Theses

In this study the production of hydrogen gas by eubacteria Thermotoga neapolitana was investigated. The organism was grown using varying media of cull peach solids and soybean meal. Hydrogen, co-products, and sugar concentrations were observed and compared.
T. neapolitana grew in medium containing peaches and soybean meal as carbon and nitrogen sources, respectively, and produced hydrogen gas. A standard medium containing glucose and yeast extract produced the most hydrogen at 31.5 mmol H2/L-medium. Withholding the vitamins and minerals from the standard the media had a significant effect on hydrogen production reducing the amount of gas produced to 25.8 mmol H2/L-medium. …


Laser-Assisted Printing Of Alginate And Cellular Tubes, Jingyuan Yan May 2013

Laser-Assisted Printing Of Alginate And Cellular Tubes, Jingyuan Yan

All Theses

Laser-assisted printing such as laser-induced forward transfer (LIFT) has found increasing biofabrication applications as an orifice-free cell/organ printing approach. Unfortunately, there have been very few studies on its efficacy of three-dimensional (3D) printing performance. In addition, the effects of printing parameters on jet/droplet formation during the printing of Newtonian and non-Newtonian fluids are lacking. Therefore, it is important to investigate its printing process and quality. The resulting knowledge will help to better control the resulting printing quality and feature resolution.
The objective of this study is to investigate the feasibility of laser-assisted 3D printing process and its applicability in making …


Parallex File System (Pxfs): Bridging The Gap Between Exascale Processing Capabilities And I/O Performance, Shane Snyder May 2013

Parallex File System (Pxfs): Bridging The Gap Between Exascale Processing Capabilities And I/O Performance, Shane Snyder

All Theses

Due to processors reaching the maximum performance allowable by current technology, architectural trends for computer systems continue to increase the number of cores per processing chip to maximize system performance. Most estimates suggest massively parallel systems will be available within the decade, containing millions of cores and capable of exaFlops of performance. New models of execution are necessary to maximize processor utilization and minimize power costs for these exascale systems. ParalleX is one such execution model, which attempts to address inefficiencies of current execution models by exposing fine-grained parallelism, increasing system utilization using asynchronous workflow, and resolving resource contention through …


A Cradle To Farm Gate Life Cycle Analysis Of Water Use In U.S. Pork Production, Eric Boles May 2013

A Cradle To Farm Gate Life Cycle Analysis Of Water Use In U.S. Pork Production, Eric Boles

Graduate Theses and Dissertations

The intent of this study was to analyze water use across a range of regions, scales and practices of the U.S. pork industry. A Life Cycle Assessment of water use within the pork supply chain was performed. Cumulative water use was the environmental impact category used in the LCA to evaluate the impacts of pork production processes throughout the pork supply chain. The functional unit for the analysis was the volume of water required to produce one kilogram of swine (live weight) at the farm gate.

A comprehensive literature review was used to design and propagate algorithms for the National …


Expression, Production, And Purification Of Novel Therapeutic Proteins, Mckinzie Shea Fruchtl May 2013

Expression, Production, And Purification Of Novel Therapeutic Proteins, Mckinzie Shea Fruchtl

Graduate Theses and Dissertations

Interest in the production of recombinant proteins consisting of collagen binding domain (CBD) fused to a bioactive material has increased due to the targeting/attachment capabilities of CBD. For example, CBD fusions can be applied to the reversing of bone density loss and the repair of the eardrum, specifically, by choosing an appropriate fusion partner (parathyroid hormone or epidermal growth factor). The production of CBD fusions was examined using batch and fed-batch culturing of Escherichia coli to express the fusion proteins, and affinity chromatography to isolate the final product.

Different medium formulations, feeding strategies, and induction methods were tested in order …


Gesture Based Home Automation For The Physically Disabled, Alexander Hugh Nelson May 2013

Gesture Based Home Automation For The Physically Disabled, Alexander Hugh Nelson

Graduate Theses and Dissertations

Paralysis and motor-impairments can greatly reduce the autonomy and quality of life of a patient while presenting a major recurring cost in home-healthcare. Augmented with a non-invasive wearable sensor system and home-automation equipment, the patient can regain a level of autonomy at a fraction of the cost of home nurses. A system which utilizes sensor fusion, low-power digital components, and smartphone cellular capabilities can extend the usefulness of such a system to allow greater adaptivity for patients with various needs. This thesis develops such a system as a Bluetooth enabled glove device which communicates with a remote web server to …


The Geometry And Sensitivity Of Ion-Beam Sculpted Nanopores For Single Molecule Dna Analysis, Ryan Connor Rollings May 2013

The Geometry And Sensitivity Of Ion-Beam Sculpted Nanopores For Single Molecule Dna Analysis, Ryan Connor Rollings

Graduate Theses and Dissertations

In this dissertation, the relationship between the geometry of ion-beam sculpted solid-state nanopores and their ability to analyze single DNA molecules using resistive pulse sensing is investigated. To accomplish this, the three dimensional shape of the nanopore is determined using energy filtered and tomographic transmission electron microscopy. It is shown that this information enables the prediction of the ionic current passing through a voltage biased nanopore and improves the prediction of the magnitude of current drop signals when the nanopore interacts with single DNA molecules. The dimensional stability of nanopores in solution is monitored using this information and is improved …


New Effects Of Aging And Lattice Intercalation On Surface Properties Of Titanate Nanobelts, Roger Williams May 2013

New Effects Of Aging And Lattice Intercalation On Surface Properties Of Titanate Nanobelts, Roger Williams

Graduate Theses and Dissertations

Titanate nanobelts (NBs) have structural characteristics beyond that of clays. Due to a negatively charged lattice matrix of edge-shared TiO6-octahedra, the location of intercalated cations within the interlayer space may dictate the charge-conductions. This environment may in turn govern the lattice-framework's stability and surface properties, based upon our preliminary

data.

On that basis, these nanomaterials have been found in our lab to possess superb biological compatibility that is closely related to the types of the intercalated cations. In addition, a prolonged agitation was proven to enable us to manipulate the titanate NBs' length. In a parallel study, a ripening was …


Greening The Streets: A Comparison Of Sustainable Stormwater Management In Portland, Oregon And Los Angeles, California, Na'ama Schweitzer May 2013

Greening The Streets: A Comparison Of Sustainable Stormwater Management In Portland, Oregon And Los Angeles, California, Na'ama Schweitzer

Pomona Senior Theses

Stormwater runoff is one of the main sources of pollution for urban waterways. Stormwater has traditionally been managed through concrete-based storm drainage systems, but the past twenty years have introduced an alternative in the form of green infrastructure. Green infrastructure for stormwater management involves the use of low impact development (LID), often vegetated facilities to mimic natural hydrologic systems that capture and allow infiltration of rainwater where it falls and from impervious surfaces upstream, before entering the drainage system. Portland, Oregon and Los Angeles, California have adopted green infrastructure into their stormwater management plans. For this project, bioswales, a form …


Environmentally Friendly Sizing Agent From Corn Distillers Dried Grains, Yue Zhang May 2013

Environmentally Friendly Sizing Agent From Corn Distillers Dried Grains, Yue Zhang

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Distillers dried grains (DDGS), the coproducts of corn ethanol production, were used as a textile sizing agent on cotton, polyester and polyester/cotton blends in an effort to find inexpensive and biodegradable alternatives to sizing agents such as poly(vinyl alcohol) that are currently used. Although DDGS is an inexpensive, biodegradable and abundant co-product, it has limited industrial applications. DDGS is a mixture of carbohydrates, proteins and oil which are used as sizing agents or as size additives. The effects of DDGS extraction conditions on sizing evaluation parameters such as fiber adhesion, film properties, viscosity and fabric abrasion were studied in comparison …


Production, Control And Actuation Of Micron-Sized Particles In A Microfluidic T-Junction, James Wilson May 2013

Production, Control And Actuation Of Micron-Sized Particles In A Microfluidic T-Junction, James Wilson

HIM 1990-2015

This research is directed towards understanding the mechanisms associated with the manufacture of solid microspheres less than 100 [micrometers], from liquid droplets with nanosuspensions in a microfluidic T-junction, which are heated downstream of the channel. Preliminary material characterization tests on colloidal suspensions of alumina and copper oxide demonstrate promising temperature dependent viscosity results indicating solidification in the temperature range of 40°C-50°C. The solidification mechanism is referred to as Temperature Induced Forming and is described by polymeric bridges formed between nanoparticles in suspension at elevated temperatures, resulting in a solid structure. The polymer network results from the ionization of alumina at …