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Characterization Of Colloidal Nanoparticle Aggregates Using Light Scattering Techniques, Mehmet Kozan

University of Kentucky Doctoral Dissertations

Light scattering is a powerful characterization tool for determining shape, size, and size distribution of fine particles, as well as complex, irregular structures of their aggregates. Small angle static light scattering and elliptically polarized light scattering techniques produce accurate results and provide real time, non-intrusive, and in-situ observations on prevailing process conditions in three-dimensional systems. As such, they complement conventional characterization tools such as SEM and TEM which have their known disadvantages and limitations. In this study, we provide a thorough light scattering analysis of colloidal tungsten trioxide (WO3) nanoparticles in the shape of irregular nanospheres and cylindrical nanowires, and …

Capacitance Metrology Of Curved Surfaces: Study And Characterization Of A Novel Probe Design, Philip T. Smith Jr.

University of Kentucky Doctoral Dissertations

Capacitive sensors are frequently applied to curved target surfaces for precision displacement measurements. In most cases, these sensors have not been recalibrated to take the curvature of the target into consideration. This recalibration becomes more critical as the target surface becomes smaller in comparison to the sensor. Calibration data are presented for a variety of capacitance probe sizes with widely varying geometries. One target surface particularly difficult to characterize is the inner surface of small holes, less than one millimeter in diameter. Although contact probes can successfully measure the inner surface of a hole, these probes are often fragile and …

Controlled Release Of Osteotropic Molecules Stimulates In Vitro Cellular Activity And In Vivo Local Bone Regeneration, Ju Hyeong Jeon

University of Kentucky Doctoral Dissertations

Bone defects treatment and reconstructive surgery continues to increase at a significant rate. Current bone defect treatments are autotransplantation, allograft, and xenografts create many problems such as, inflammation, infection and chronic pain. Moreover, allografts and xenografts arouse immune rejection. These problems have led to development of controlled release system for use as alternatives to autografts, allografts and xenografts in bone repair. There have been many approaches for sustained drug delivery in local bone regeneration using biodegradable polymers and osteotropic biomolecules. This dissertation presents new approaches that apply intermittent drug delivery for local bone regeneration. In the first, the osteotropic molecules …

Enhanced Fire Retardancy Of Vinyl Ester Resins By Combination Of Additives, Grace Chigwada, Charles A. Wilkie

Chemistry Faculty Research and Publications

In pursuit of fire-retardant materials, vinyl ester resins were combined with commercially available fire retardants at lower loadings than that at which they are usually effective when used alone. The thermal stability and flammability of the various combinations of fire retardants were evaluated by thermogravimetric analysis and cone calorimetric analysis. With some combinations, the 50% degradation temperature was improved by about 5-10ºC Different additives affected the flammability to varying extents and some combinations resulted in an enhanced fire retardancy compared to the additives used alone. The combinations that showed the best reductions in the peak heat release rate (PHRR) were …

Sex Offenders, Sexuality, And Social Control: A Case Study In The Social Construction Of A Social Problem, Lisa Marie Kruse

Master's Theses and Doctoral Dissertations

Legislation regarding sex offenses is often passed swiftly with little to no evaluation of the effectiveness of such policies on preventing recidivism and protecting the public. Further, little criticism is raised despite overwhelming evidence that sex offender registration and community notification is ineffective and has many negative consequences. The societal reaction is created through moral panics resulting in views that are not always reflective of the nature of the problem. In effect, the policies put into place in the name of declaring war on the deviant behavior reflect these views and do not target the specific problem.

While the first …

Conserved Amino Acids In Each Subunit Of The Heteroligomeric Trna M1A58 Mtase From Saccharomyces Cerevisiae Contribute To Trna Binding, Sarah G. Ozanick, Janusz M. Bujnicki, Daniel S. Sem, James T. Anderson

Chemistry Faculty Research and Publications

In Saccharomyces cerevisiae, a two-subunit methyltransferase (Mtase) encoded by the essential genes TRM6 and TRM61 is responsible for the formation of 1-methyladenosine, a modified nucleoside found at position 58 in tRNA that is critical for the stability of . The crystal structure of the homotetrameric m¹A58 tRNA Mtase from Mycobacterium tuberculosis, TrmI, has been solved and was used as a template to build a model of the yeast m¹A58 tRNA Mtase heterotetramer. We altered amino acids in TRM6 and TRM61 that were predicted to be important for the stability of the heteroligomer based on …

An Analysis Of Gender Differences In Property Crime Arrest Rates, Chanika Renee Jones

LSU Doctoral Dissertations

This dissertation examined the relationship between employment conditions and property-crime arrest rates of working-aged individuals, using gender-specific state-level data from 1979-2001, complied from raw arrest data of the FBI's Uniform Crime Reports and the Census Bureau's annual March Current Population Survey. These data were analyzed using Ordinary Least Squares Regression. The data was disaggregated by gender and underemployment indicators such as percent unemployed, percent subunemployed, percent low wages, and percent low hours, were utilized to test the unemployment-crime relationship. Controls for race, age, and region were also included in this analysis, as they may influence the U-C relationship. The analysis …

Channel Modeling And Resource Allocation In Ofdm Systems, Xiang Gao

LSU Doctoral Dissertations

The increasing demand for high data rate in wireless communication systems gives rise to broadband communication systems. The radio channel is plagued by multipath propagation, which causes frequency-selective fading in broadband signals. Orthogonal Frequency-Division Multiplexing (OFDM) is a modulation scheme specifically designed to facilitate high-speed data transmission over frequency-selective fading channels. The problem of channel modeling in the frequency domain is first investigated for the wideband and ultra wideband wireless channels. The channel is converted into an equivalent discrete channel by uniformly sampling the continuous channel frequency response (CFR), which results in a discrete CFR. A necessary and sufficient condition …

Electrodeposition Of Multilayered Nanostructures For Giant Magnetoresistance And Thermoelectric Applications, Despina Davis

LSU Doctoral Dissertations

The electrodeposition of novel materials such as multilayer nanotubes for giant magneto resistance (GMR) applications and bismuth telluride nanotubes for thermoelectric applications are presented in this dissertation. The motivation for the multilayer electrodeposition is the investigation of giant magnetoresistance (GMR), a change in the material resistance in an applied magnetic field as a consequence of antiferromagnetic coupling. The nanowire high aspect ratio geometry allows the measurement of GMR with the current applied perpendicular to the plane (CPP) of the multilayers, which has been theoretically identified as being larger than the GMR in the (CIP) configuration (current in plane of multilayers). …

Bottom-Up International Lawmaking: Reflections On The New Haven School Of International Law, Janet K. Levit

Articles, Chapters in Books and Other Contributions to Scholarly Works

No abstract provided.

Investigation On The Antioxidant Capabilities Of Spice Extracts In Inhibition Of Long Chain Polyunsaturated Fatty Acids Oxidation And Cholesterol, Sandeep D. Bhale

LSU Doctoral Dissertations

Antioxidant capabilities of the spice extract of ginger, oregano, rosemary and turmeric were evaluated by monitoring inhibition of DHA and EPA in a menhaden fish oil model and cholesterol oxidation model system. The spice extracts were mixed with the fish oil at 1, 2.5 and 5 % (w/w) and 1, 2.5 and 5mg (dw) were used in cholesterol study. The temperatures 150oC and 175oC were used for the oxidation study and a 60oC was used for incubation storage. The methanol extracts of all four spices demonstrated significant capability in retaining the DHA and EPA, after subjected to oxidation when compared …

Wood Liquefaction In The Presence Of Phenol With A Weak Acid Catalyst And Its Potential For Novolac Type Wood Adhesives, Hui Pan

LSU Doctoral Dissertations

Wood liquefaction was conducted using phenol as a reagent solvent with oxalic acid as a catalyst. A series of studies were done on liquefied wood, liquefied wood residues, novolac-type liquefied wood resins, and bio-composites fabricated from liquefied wood resin. The results of the liquefied wood residue characterization revealed that the liquefaction reactions conducted in different reaction vessels underwent different liquefaction mechanisms. The crystallinity indexes of the liquefied wood residues were higher than that of the original wood, indicating that the amorphous lignin was the most susceptible component in wood to the liquefaction reaction. Fe2+ and Fe3+ ions were found to …

Turbulence Modeling For Film Cooling Flows, Asif Hoda

LSU Doctoral Dissertations

An improved two equation turbulence model has been developed in this dissertation to better predict the complex film cooling flow field that is formed from the interaction of a coolant jet and a crossflow over a modeled turbine blade surface. Film cooling of turbine blades is commonly employed to effectively protect turbine blades from thermal failure and thereby to allow higher inlet temperatures in order to increase the efficiency of gas turbine engines. Film cooling involves the injection of rows of coolant jets from slots on the surface of a turbine blade which is then bent over by the crossflow …

Eigenvalue Optimization And Its Applications In Buckling And Vibration, Srinivas Gopal Krishna

LSU Doctoral Dissertations

Eigenvalue problems are of immense interest and play a pivotal role not only in many fields of engineering but also in pure and applied mathematics. An in-depth understanding of this class of problems is a pre-requisite for vibration and buckling analyses of structures. Design optimization of structures to prevent failure due to instability (bucking) and vibration introduces the problem of determining optimal physical parameters such that load carrying capacity or the fundamental natural frequency is maximized. A classical example of such problems is the Lagrange problem of determining the shape of the strongest column against buckling. The primary objective of …

Balch Internet Research And Analysis Tool Development Case Study, Charles V. Balch

LSU Doctoral Dissertations

The Internet has become increasing popular as a vehicle to deliver surveys. An essential objective of research is to collect accurate data and there has been little work to insure that Internet survey systems are employing best practices as defined by academic and professional research to collect data. My dissertation reviews the current literature relating to best practices in Internet survey design and best practices in software design and development. I then document the development and deployment of an Open Source and publicly licensed Internet survey system that allows researchers to easily create, deploy, and analyze the results of Internet …

Using Time-Lapse And Stroboscopic Photography To Enhance Student Understanding Of Plant Growth, Structure, And Pollination: An Inquiry-Based Study, Louis John Schultz

LSU Doctoral Dissertations

This study was designed to evaluate the effects of allowing students to generate their own images in a science class as opposed to using pre-existing images. The participants in the study were 7th grade science students enrolled in a small, rural, Louisiana school. A mixed methods design was used so that call available data was collected and analyzed. The lessons used in the study were based on plant structure, growth, and propagation which fit into the mandated 7th grade science curriculum. The students were involved in the taking of still, time-lapse, and stroboscopic images throughout the study. Although an analysis …

Spatial And Temporal Structure Of Typhoid Fever In Washington, D.C., 1895-1909: A Geographic Information Systems Exploration Of Urban Health Concerns, Sarah Elizabeth Hinman

LSU Doctoral Dissertations

The period between 1880 and 1920 was one of the most dynamic in the history of medicine. Morbidity and mortality rates for infectious diseases dropped quickly. Concurrently, miasmatic theory gave way to germ theory. Many of these dynamic changes occurred in the urban centers of North America, which were also entering into a period of dramatic growth and change. Following the 1905 completion of infrastructure improvements intended to improve public health in Washington, D.C., typhoid fever rates unexpectedly increased. Previously, for mitigation purposes, Dr. George Kober investigated a typhoid epidemic in 1895, and as a result of the 1906 increase …

Bridging The Academic Biotechnology Commercialization Gap: Can The Mission Of The Public Research University Be Preserved?, Anne Rossi Jarrett

LSU Doctoral Dissertations

The primary purpose of this exploratory study was to determine if there is a best model available for public research universities to use when they are implementing or revising a mechanism to commercialize early-stage academic biotechnology inventions and discoveries. Unintended consequences, including conflicts of interest, faculty roles, and the mission of the public research university were also studied in order to determine if these issues could be managed or removed when academic biotechnology commercialization occurred. This study compared the best practices biotechnology commercialization model at the University of California San Diego (UCSD) with biotechnology commercialization mechanisms in place in three …

How The Internet Is Shaping The Chilean Scientific Community: Globalization And Dependency, Richard B. Duque

LSU Doctoral Dissertations

The Internet has emerged as a catalyst for global knowledge production. This is supported by its positive impacts in the First World. A progressive assessment argues that the Internet will be the "elixir" that brings immediate visibility and relevance to scientific communities in the periphery. Yet, Internet diffusion is often framed by past technology failures that further widen global divides. This characterizes an "affliction" argument. The "teething argument" suggests that adoption within the Third World is tentative at best with benefits unfolding over time in some regions but not others. This dissertation is a qualitative and quantitative study that tests …

Synthesis And Functionalizations Of Tetrapyrrole Derivatives, Lijuan Jiao

LSU Doctoral Dissertations

Chapter 1 of this Dissertation presents a brief overview of the history of tetrapyrrole derivatives and of their fundamental properties. Overviews of porphyrins, benzoporphyrins, chlorins and porphycenes are presented. Work presented in Chapter 2 through Chapter 4 mainly focuses on the syntheses and functionalization of chromophore-extended porphyrin derivatives. Several new synthetic routes for the syntheses and functionalizations of extended porphyrins either at the β-position or at the meso-position of porphyrin are developed. From these improved synthetic routes, the regio-selective syntheses of porphyrin derivatives are described. Chapter 2 mainly focuses on the syntheses of β,β'-fused methylenepropanoporphyrins and related porphyrin dimers. Chapter …

Engineering A Photo-Control Mechanism For Rna Interference, Richard Andrew Blidner

LSU Doctoral Dissertations

RNA interference (RNAi) is a phenomenon in which RNA molecules elicit potent and sequence-specific post-transcriptional gene silencing. Nucleic acid chemical modifications have been incorporated to improve their pharmacological properties. Despite numerous developments in chemical modifications for increased stability, safety, and efficiency of these therapeutic agents, they still face challenges of spatial and temporal targeting. One potential targeting strategy uses photocaging techniques, which involves the covalent attachment of photolabile compounds to the effector NA species that blocks bioactivity until exposed to near UV-light. This work demonstrates that fully-2’-fluorinated nucleic acids (FNAs) can elicit RNAi and that these effectors are resistant to …

Potential Of A Suite Of Robot/Computer-Assisted Motivating Systems For Personalized, Home-Based, Stroke Rehabilitation, Michelle J. Johnson, Xin Feng, Laura M. Johnson, Jack M. Winters

Electrical and Computer Engineering Faculty Research and Publications

Background

There is a need to improve semi-autonomous stroke therapy in home environments often characterized by low supervision of clinical experts and low extrinsic motivation. Our distributed device approach to this problem consists of an integrated suite of low-cost robotic/computer-assistive technologies driven by a novel universal access software framework called UniTherapy. Our design strategy for personalizing the therapy, providing extrinsic motivation and outcome assessment is presented and evaluated.

Methods

Three studies were conducted to evaluate the potential of the suite. A conventional force-reflecting joystick, a modified joystick therapy platform (TheraJoy), and a steering wheel platform (TheraDrive) were tested separately with …

Predicting Water Quality Effects On Bay Anchovy (Anchoa Mitchilli) Growth And Production In Chesapeake Bay: Linking Water Quality And Individual-Based Fish Models, Aaron Thomas Adamack

LSU Doctoral Dissertations

Water quality in the Chesapeake Bay and the Patuxent River has decreased since the 1950s due to an increase in nutrient loadings. Increased nutrient loads have caused an increase in the extent and duration of hypoxic conditions. Restoration via large-scale reductions in nutrient loadings is now underway. How reducing nutrient loadings will affect water quality is well predicted; however the effect on fish is generally unknown as most water quality models do not include trophic levels higher than zooplankton. I combined two water quality models with bay anchovy models (Anchoa mitchilli) to examine the effects of changes in nutrient loadings …

Effect Of Hole Configurations On Film Cooling From Cylindrical Inclined Holes For The Application To Gas Turbine Blades, Yiping Lu

LSU Doctoral Dissertations

Film cooling is one of the cooling systems investigated for the application to gas turbine blades. Gas turbines use film cooling in addition to turbulated internal cooling to protect the blades outer surface from hot gases. The present study concentrates on the experimental and numerical investigation of film cooling performance for a row of cylindrical holes in a modern turbine blade. The adiabatic film effectiveness and the heat transfer coefficient are determined experimentally on a flat plate downstream of a row of inclined different geometries hole exit by using a single test transient IR thermography technique. The focus of this …

Flow And Distribution Of Water In Fractional Wettability Unsaturated Porous Media, Zaydoun Turkey Abusalem

LSU Doctoral Dissertations

In recent years, interest in fluid flow and transport in the unsaturated zone has gained more attention, due to growing concerns that the quality of the subsurface environment is adversely affected by agricultural, industrial, and municipal activities. The wettability properties (e.g., water repellency) of soil in the unsaturated zone play an important role in determining fluid movement and ultimate distributions. A number of studies have shown that preferential flow and spatially variable moisture content is likely to occur in water repellant soils. Development of appropriate constitutive relations for numerical modeling becomes even more difficult in systems that contain water repellant …

Knowledge-Based Methods For Automatic Extraction Of Domain-Specific Ontologies, Janardhana R. Punuru

LSU Doctoral Dissertations

Semantic web technology aims at developing methodologies for representing large amount of knowledge in web accessible form. The semantics of knowledge should be easy to interpret and understand by computer programs, so that sharing and utilizing knowledge across the Web would be possible. Domain specific ontologies form the basis for knowledge representation in the semantic web. Research on automated development of ontologies from texts has become increasingly important because manual construction of ontologies is labor intensive and costly, and, at the same time, large amount of texts for individual domains is already available in electronic form. However, automatic extraction of …

Computer Model Of Hybrid Compensator Of Fast Varying Loads, Veronica Bohorquez

LSU Doctoral Dissertations

A computer model of the hybrid compensator of fast varying loads was developed in this dissertation. The computer model was implemented in MFC Visual C++ compiler version 6.0. The classification of fast varying loads and effects of their operation in distribution systems were described in this dissertation. The power properties of fast varying loads were expressed in terms of the Currents' Physical Components Theory. Therefore, the Currents' Physical Components Theory was applied to systems with non-periodic voltages and currents. The supply current of the fast varying loads was decomposed into the useful and the useless components using an algorithm based …

An Investigation Of Maternal Psychopathology As A Moderator Of Child Response Following Hurricane Katrina, Ann Wingate Spell

LSU Doctoral Dissertations

Previous disaster research has focused on possible risk factors that contribute to child psychological distress following disaster exposure. One of these factors, parental psychopathology, has consistently been indicated as associated with and predictive of child functioning post-disaster. In related areas of violence exposure, researchers have gone beyond correlation and prediction in their attempt to elucidate the relationship between parental psychopathology and child functioning post-trauma. Such researchers have investigated and confirmed parental psychopathology as a moderator variable in the relationship between child violence exposure and child functioning. Thus, in considering the status of research regarding risk factors of child functioning post-disaster …

The Effects Of 3-Dimensional Cadd Modeling Software On The Development Of The Spatial Ability Of Ninth Grade Technology Discovery Students, K. Lynn Basham

LSU Doctoral Dissertations

The purpose of this quantitative study was to determine if there is a difference in the development of spatial abilities of ninth grade Technology Discovery students in Mississippi as measured by the Purdue Visualization of Rotations Test. Students experienced one of three differing instructional methods utilizing Pro/Desktop® 3-D CADD solid modeling software. Participants were students in Mississippi schools operating on a 4 x 4 block schedule during either fall or spring semesters during the 2005-2006 school year, and a control group of students whose schools did not offer CADD. Instructional material designed by the researcher was used for two instructional …

Application-Specific Reliable Data Transfer In Wireless Sensor Networks, Damayanti Datta

LSU Doctoral Dissertations

A wireless sensor network (WSN) is a collection of sensor nodes and base stations connected via wireless medium. It sends data collected from the nodes to the base stations for generating information. The size and low cost of the sensor nodes as well as the WSN's ability to connect without wired links are its key advantages which enable it to be deployed in hostile or inaccessible environments at low cost. However, WSNs suffer from high data loss due to the inherent weaknesses in a wireless transmission medium, transmission problems in hostile environments due to human interference, etc. and node failures …