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2012

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Crosstalk Between Lysophospatidic Acid (Lpa) And Transforming Growth Factor Beta (Tgfβ) In Breast And Ovarian Cancer Cells, Jinhua Wu Jan 2012

Crosstalk Between Lysophospatidic Acid (Lpa) And Transforming Growth Factor Beta (Tgfβ) In Breast And Ovarian Cancer Cells, Jinhua Wu

Theses and Dissertations

Lysophosphatidic acid (LPA) and transforming growth factor beta (TGFβ) are platelet-derived intercellular mediators of cell proliferation and motility. LPA is a general growth, survival and motility-stimulating factor in mammalian cells. TGFβ prevents proliferation of normal epithelial cells. However, the growth-inhibitory effect of TGFβ is lost or reduced in most malignant cells. Instead, TGFβ promotes migration and invasion of advanced cancer cells. Since LPA and TGFβ are both present in the blood and tumor microenvironments, we were interested in signal integration and functional outcomes in malignant epithelial cells in an LPA and TGFβ co-stimulatory context. In a subset of breast and …

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Investigating The Role Of Α6 And Α4 Containing Neuronal Nicotinic Acetylcholine Receptors In Nicotine And Cocaine Conditioned Place Preference Tests In Mice., Sarah Sanjakdar Jan 2012

Investigating The Role Of Α6 And Α4 Containing Neuronal Nicotinic Acetylcholine Receptors In Nicotine And Cocaine Conditioned Place Preference Tests In Mice., Sarah Sanjakdar

Theses and Dissertations

Neuronal nicotinic acetylcholine receptors modulate both cholinergic and non-cholinergic synaptic transmission. Our research concerns α6 and α4 neuronal nicotinic subunits because they often co-assemble with the β2 subunit, which has abundant expression in the CNS and previous work has demonstrated that β2* nAChRs are involved in nicotine and cocaine reward. α6β2* and α4β2* nAChRs are highly expressed in midbrain, which is known to be critical for the incentive salience associated with natural and artificial (drug) reward. Our goal was to assess the role of α6β2* and α4β2* nAChRs in nicotine and cocaine reward using an unbiased conditioned place preference (CPP) …

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Identifying Sortase A Variants With Higher Catalytic Effeciency, Muna Suliman Jan 2012

Identifying Sortase A Variants With Higher Catalytic Effeciency, Muna Suliman

Theses and Dissertations

In the past two decades, the field of protein engineering has evolved rapidly to include new genetic and chemical techniques to alter protein function. Protein engineering seeks to improve enzyme properties through powerful methods that specifically incorporate novel or improved function in proteins. One such method is protein ligation, which is used to selectively link synthetic and recombinant polypeptides. Due to the limitations of current protein labeling techniques, simple site-specific modification methods remain in high demand. Use of enzyme-based labeling has been the focus of various studies because of its substrate specificity. Sortase-mediated transpeptidation is one approach that has been …

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Investigation Of Doped Zno By Molecular Beam Epitaxy For N- And P-Type Conductivity, Huiyong Liu Jan 2012

Investigation Of Doped Zno By Molecular Beam Epitaxy For N- And P-Type Conductivity, Huiyong Liu

Theses and Dissertations

This dissertation presents an investigation of the properties, especially the electrical properties, of doped ZnO films grown by plasma-assisted molecular beam epitaxy (MBE) under different conditions. The interest in investigating ZnO films is motivated by the potential of ZnO to replace the currently dominant ITO in industries as n-type transparent electrodes and the difficulty in achieving reliable and reproducible p-type ZnO. On the one hand, n-type ZnO heavily doped with Al or Ga (AZO or GZO) is the most promising to replace ITO due to the low cost, abundant material resources, non-toxicity , high conductivity, and high transparency. On the …

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Regeneration Of Electrospun Bioresorbable Vascular Grafts: A Phenomenon Associated With Vascular Graft Properties And Macrophage Phenotypes (M1/M2), Koyal Garg Jan 2012

Regeneration Of Electrospun Bioresorbable Vascular Grafts: A Phenomenon Associated With Vascular Graft Properties And Macrophage Phenotypes (M1/M2), Koyal Garg

Theses and Dissertations

Macrophages (MФ) and mast cells are important cell types in the context of tissue remodeling and regeneration. Mast cells participate in the early stages of wound healing and modulate the acute inflammatory responses to biomaterials. Mast cells can secrete a myriad of different cytokines by the process of degranulation; the process of regulated secretion in which preformed contents stored in their granules are rapidly released by exocytosis. Some of these cytokines such as IL-4, IL-13 and TNF-α can modulate the MФ phenotype. Macrophages (MΦ) are innate immune cells, crucial for tissue homeostasis, presentation of foreign and self-antigens following infection/injury, pathogen …

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Novel Fluorous Hybrid Surface Modification Characterized By Wetting Dynamics, Morphology And Nanomechanics, Sithara Nair Jan 2012

Novel Fluorous Hybrid Surface Modification Characterized By Wetting Dynamics, Morphology And Nanomechanics, Sithara Nair

Theses and Dissertations

The surface response of a polymer substrate to external stimuli such as initial wetting is controlled by the outermost molecular layer. Thus, changes on the nanoscale may be engaged to control macroscale wetting behavior. Our work has predominantly focused on surface modification of conventional polyurethane coatings (HMDI-BD-PTMO). Studies on network constrained phase separation and facile polydimethylsiloxane surface functionalization led to the discovery of a simpler one-step and more general approach to functional polymer surfaces that we have designated as “Bottle-Brush Nanoglass” (BB-NG) after the two principle components: (a) a polyoxetane soft block “spine” with side chain “A” bristles and triethoxysilyl …

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Effects Of Strain On Dielectric Properties Of Ferroelectric Ba0.5sr0.5tio3 Films, Hongrui Liu Jan 2012

Effects Of Strain On Dielectric Properties Of Ferroelectric Ba0.5sr0.5tio3 Films, Hongrui Liu

Theses and Dissertations

Owing to the large electric-field-dependent permittivity, ferroelectric thin films have attracted a great deal of attention on applications in miniature tunable microwave components with high performance and cost reduction, such as phase shifters, tunable oscillators, delay lines, and antennas. These tunable devices require large change in the dielectric constant with applied field and a low loss at microwave frequencies. As one of the promising ferroelectric materials, barium strontium titanate thin film, especially Ba0.5Sr0.5TiO3 (BST) films, have raises great research interests due to its high dielectric constant, which is tunable in an external electric field, combined with relative low loss at …

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Deposition Near Film Cooling Holes On A High Pressure Turbine Vane, Weiguo Ai, Nathan Murray, Thomas H. Fletcher, Spencer Harding, Scott Lewis, Jeffrey P. Bons Jan 2012

Deposition Near Film Cooling Holes On A High Pressure Turbine Vane, Weiguo Ai, Nathan Murray, Thomas H. Fletcher, Spencer Harding, Scott Lewis, Jeffrey P. Bons

Faculty Publications

Deposition on film-cooled turbine components was studied in an accelerated test facility. The accelerated deposition facility seeds a natural-gas burning combustor with finely ground coal ash particulate at 1180 C and 180 m/s (M=0.25). Both cylindrical and shaped holes, with and without thermal barrier coating, were studied over a range of blowing ratios from 0.5 to 4.0. Coolant density ratios were maintained at values from 2.1 to 2.4. Deposition patterns generated with the cylindrical film cooling holes indicated regions of low deposition in the path of the coolant with heightened deposition between film holes. This distinctive pattern was more accentuated …

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Prediction Of Tar And Light Gas During Pyrolysis Of Black Liquor And Biomass, Thomas H. Fletcher, Harland R. Pond, Jarom Webster, Judson Wooters, Larry L. Baxter Jan 2012

Prediction Of Tar And Light Gas During Pyrolysis Of Black Liquor And Biomass, Thomas H. Fletcher, Harland R. Pond, Jarom Webster, Judson Wooters, Larry L. Baxter

Faculty Publications

A generalized model for describing the pyrolysis behavior of low-grade fuels is being developed for incorporation into larger combustion simulation models. Light gas and tar yields from black liquor or biomass pyrolysis can be predicted using the chemical percolation devolatilization (CPD) model originally developed for coal. The initial approach is to measure the average chemical structures in a black liquor sample using 13C NMR spectroscopy. These chemical structures are then used in pyrolysis model predictions. With few changes from the coal-derived kinetic parameters, the model describes the organic pyrolysis behavior of black liquor samples obtained in a nitrogen-purged furnace. It …

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Coal Swelling Model For Pressurized High Particle Heating Rate Pyrolysis Applications, Randy C. Shurtz, Joseph W. Hogge, Kade C. Fowers, Gregory S. Sorensen, Thomas H. Fletcher Jan 2012

Coal Swelling Model For Pressurized High Particle Heating Rate Pyrolysis Applications, Randy C. Shurtz, Joseph W. Hogge, Kade C. Fowers, Gregory S. Sorensen, Thomas H. Fletcher

Faculty Publications

A model was previously developed to describe the decrease in swelling during coal pyrolysis at atmospheric pressure when maximum particle heating rates increase from 104 K/s to 105 K/s. That model included effects of coal type using chemical structure properties. This paper presents results of new experiments to study the effects of elevated pressure and high heating rates on coal pyrolysis. A pressurized flat-flame burner (PFFB) was designed and built to conduct these studies. The pyrolysis experiments reported in this paper were conducted at particle heating rates of ∼105 K/s and maximum gas temperatures of 1700 to 1900 …

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Computational Analysis Of Conjugate Heat Transfer And Particulate Deposition On A High Pressure Turbine Vane, Weiguo Ai, Thomas H. Fletcher Jan 2012

Computational Analysis Of Conjugate Heat Transfer And Particulate Deposition On A High Pressure Turbine Vane, Weiguo Ai, Thomas H. Fletcher

Faculty Publications

Numerical computations were conducted to simulate flash deposition experiments on gas turbine disk samples with internal impingement and film cooling using a computational fluid dynamics (CFD) code (FLUENT). The standard k-epsilon turbulence model and Reynoldsaveraged Navier–Stokes were employed to compute the flow field and heat transfer. The boundary conditions were specified to be in agreement with the conditions measured in experiments performed in the BYU turbine accelerated deposition facility (TADF). A Lagrangian particle method was utilized to predict the ash particulate deposition. Userdefined subroutines were linked with FLUENT to build the deposition model. The model includes particle sticking/rebounding and particle …

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Ballistic Imaging Of Sprays At Diesel Relevant Conditions, Jason M. Porter, S. P. Duran, T. E. Parker Jan 2012

Ballistic Imaging Of Sprays At Diesel Relevant Conditions, Jason M. Porter, S. P. Duran, T. E. Parker

Faculty Publications

Diesel engines are an important aspect of our transportation infrastructure, whose performance is greatly affected by the characteristics of the spray from their injectors. Characterization of the injector’s spray is therefore tantamount to clean-running efficient diesel motors. In this study, a ~15 ps pulsed Leopard D-10 laser is used along with an optical Kerr Cell to realize ballistic images of high-delivery-pressure dodecane sprays injected into a quiescent air environment at elevated temperature and pressure. Using CS2 as the Kerr switching media and by optimizing the overlap of the gate and imaging beams, an effective high speed shuttering effect is obtained. …

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The Value Of A Master’S Degree To Recreation Professionals, Camilla J. Hodge, Brian J. Hill, Christian Brinton Jan 2012

The Value Of A Master’S Degree To Recreation Professionals, Camilla J. Hodge, Brian J. Hill, Christian Brinton

Faculty Publications

This study assessed the nature of the relationship between earning advanced degrees and career outcomes such as salary, job satisfaction, social capital, and human capital among professionals in the parks and recreation field. The sample (n = 196) was drawn from parks and recreation agencies located in the United States. Agencies, excluding educational institutions, were identified via an Internet search for parks and recreation agencies in urban areas. Findings indicated there was a positive relationship between earning a master’s degree and salary. Earning a master’s degree, however, was not significantly related to job satisfaction, social capital, or human capital. Furthermore, …

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Visualizing And Modeling Interior Spaces Of Dangerous Structures Using Lidar, Norbert H. Maerz, T. K. Assebaum, Dustin J. Williams, K. Shea, Yongjian Xi, Xiaoling Li, Ye Duan Jan 2012

Visualizing And Modeling Interior Spaces Of Dangerous Structures Using Lidar, Norbert H. Maerz, T. K. Assebaum, Dustin J. Williams, K. Shea, Yongjian Xi, Xiaoling Li, Ye Duan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

LIght Detection and Ranging (LIDAR) scanning can be used to safely and remotely provide intelligence on the interior of dangerous structures for use by first responders that need to enter these structures. By scanning into structures through windows and other openings or moving the LIDAR scanning into the structure, in both cases carried by a remote controlled robotic crawler, the presence of dangerous items or personnel can be confi rmed or denied. Entry and egress pathways can be determined in advance, and potential hiding/ambush locations identifi ed. This paper describes an integrated system of a robotic crawler and LIDAR scanner. …

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The Impact Of Service-Learning Among Other Predictors For Persistence And Degree Completion Of Undergraduate Students, Kelly Lockeman Jan 2012

The Impact Of Service-Learning Among Other Predictors For Persistence And Degree Completion Of Undergraduate Students, Kelly Lockeman

Theses and Dissertations

College completion is an issue of great concern in the United States, where only 50% of students who start college as freshmen complete a bachelor's degree at that institution within six years. Researchers have studied a variety of factors to understand their relationship to student persistence. Not surprisingly, student characteristics, particularly their academic background prior to entering college, have a tremendous influence on college success. Colleges and universities have little control over student characteristics unless they screen out lesser qualified students during the admissions process, but selectivity is contrary to the push for increased accessibility for under-served groups. As a …

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Evaluating Journal Quality And The Association For Information Systems (Ais) Senior Scholars’ Journal Basket Via Bibliometric Measures: Do Expert Journal Assessments Add Value?, Paul Benjamin Lowry, Gregory D. Moody, James Gaskin, Dennis F. Galletta, Sean L. Humpherys, Jordan B. Barlow, David W. Wilson Jan 2012

Evaluating Journal Quality And The Association For Information Systems (Ais) Senior Scholars’ Journal Basket Via Bibliometric Measures: Do Expert Journal Assessments Add Value?, Paul Benjamin Lowry, Gregory D. Moody, James Gaskin, Dennis F. Galletta, Sean L. Humpherys, Jordan B. Barlow, David W. Wilson

Faculty Publications

Information systems (IS) journal rankings and ratings help scholars focus their publishing efforts and are widely used surrogates for judging the quality of research. Over the years, numerous approaches have been used to rank IS journals, approaches such as citation metrics, school lists, acceptance rates, and expert assessments. However, the results of these approaches often conflict due to a host of validity concerns. In the current scientometric study, we make significant strides toward correcting for these limitations in the ranking of mainstream IS journals. We compare expert rankings to bibliometric measures such as the ISI Impact Factor™, the h-index, and …

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The Business Rules Approach And Its Effect On Software Testing, Thomas O. Meservy, Chen Zhang, Euntae T. Lee, Jasbir Dhaliwal Jan 2012

The Business Rules Approach And Its Effect On Software Testing, Thomas O. Meservy, Chen Zhang, Euntae T. Lee, Jasbir Dhaliwal

Faculty Publications

Codification and testing of business rules in application programs has historically been a challenge in software engineering. Many organizations have adopted the business rules approach to formalize and compartmentalize business rules as a separate component from application code. This article investigates and presents the effects of the business rules approach on testing activities in the software development life cycle at a Fortune 500 corporation. The findings suggest that the business rules approach has the potential to engage testing personnel early in the development process and to improve the efficiency and effectiveness of testing activities.

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Stability Of Rock Slopes Along Raidah Escarpment Road, Asir Area, Kingdom Of Saudi Arabia, Ahmed M. Youssef, Norbert H. Maerz, Abdulla A. Al-Otaibi Jan 2012

Stability Of Rock Slopes Along Raidah Escarpment Road, Asir Area, Kingdom Of Saudi Arabia, Ahmed M. Youssef, Norbert H. Maerz, Abdulla A. Al-Otaibi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Raidah Escarpment road is located north west of Abha city, Asir region, Kingdom of Saudi Arabia. This escarpment road represents an important corridor in the area which connects different villages and tourist resorts with each other. The total length of this road section is about 9 km which passes through a highly mountainous area. The road also passes through areas of different geological hazards (rock, debris flow, soil, and weathered zones). The different environmental factors (e.g. intensive rainy summer), variable geological and structural elements (weak rocks, slide debris weak soils, shear zones, and faults) difficult road characteristics (narrow roads …

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Appraisal Investigation Alternative Water Supply For Langdon Rural Water District, Geoffrey Brian Slick Jan 2012

Appraisal Investigation Alternative Water Supply For Langdon Rural Water District, Geoffrey Brian Slick

Theses and Dissertations

No abstract provided.

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