Digital Commons Network^™

Genome Jigsaw: Implications Of 16s Ribosomal Rna Gene Fragment Position For Bacterial Species Identification, Jennifer Mitchell

Theses and Dissertations (Comprehensive)

The 16S rRNA gene is present within all bacteria, and contains nine variable regions interspersed within conserved regions of the gene. While conserved regions remain mostly constant over time, variable regions can be used for taxonomic identification purposes. Current methodologies for characterizing microbial communities, such as those used to study the human microbiome, involve sequencing short fragments of this ubiquitous gene, and comparing these fragments to reference sequences in databases to identify the microbes present. Traditionally, whole 16S rRNA sequences with more than 97% sequence identity (id) are assigned to a single operational taxonomic unit (OTUs); each OTU being a …

Recovery From Acute Toluene Intoxication Is Facilitated By The Nmda Receptor Co-Agonist D-Serine, But Not The Gabaa Receptor Antagonist Picrotoxin, Susan R. Samuel-Herter

Theses and Dissertations (Comprehensive)

Toluene is a volatile solvent found in many household products and when intentionally inhaled results in intoxication. In rats, acute inhalation of toluene results in sedation and neurological impairments, with marked increases in ambulation and vertical behaviour during the recovery period. Previous in vitro research has shown that toluene may exert its effects by inhibiting NMDA receptors, and / or by activating GABA_A receptors. To test whether modulation of these receptors are also implicated in the changes in motor behaviour and neurological impairments resulting from toluene vapour inhalation, rats were injected with the NMDA receptor co-agonist D-serine (1000 mg/kg …

Integrated Spatial Analysis Of Volunteered Geographic Information, Haydn Lawrence

Theses and Dissertations (Comprehensive)

Volunteered Geographic Information (VGI) is becoming a pervasive form of data within geographic academic research. VGI offers a relatively new form of data, one with both potential as a sensitive way to collect information about the world, and challenges associated with unknown and heterogeneous data quality. The lack of sampling control, variable expertise in data collection and handling, and limited control over data sources are significant research challenges. In this thesis, data quality of VGI is tackled as a general composite measure based on coverage of the dataset, the evenness in the density of data, and the relative evenness in …

Fight The Dead, Fear The Living: Post-Apocalyptic Narratives Of Fear, Governance And Social Control, Samantha Lynn Kolpin

Theses and Dissertations (Comprehensive)

Post-apocalyptic narratives and themes have become increasingly popular in film, television and graphic novels. By imagining a society without the state, post-apocalyptic narratives are able to explore concerns about current forms of governance and social control. The post-apocalyptic narrative is particularly relevant in a post-9/11 society where public concerns about security and governance are prominent. In this study, I examined the potential allegorical function of the zombie narrative found in Robert Kirkman’s The Walking Dead. Specifically, this project involves an ethnographic content analysis of issues 1-100 of The Walking Dead graphic novel series. Analysis focused on the allegorical purposes of …

Microbial Community Characterization And Pathogen Profiling Of Land-Based Aquaculture Systems Using Culture-Based And Molecular-Based Fingerprinting Techniques, Nicole S. Kteily

Theses and Dissertations (Comprehensive)

The growing worldwide demand for fish production has prompted research towards intensive aquaculture. Innovative system designs, such as recirculating and flow-through aquaculture systems, have been developed to improve the efficiency and sustainability of intensive aquaculture practices. These LBAS systems exhibit a wide range of spatial and temporal heterogeneity. Although such heterogeneity suggests the potential for culture water to support a diverse and spatially complex assortment of microorganisms, there is a lack of information regarding the overall diversity and composition of microbial communities (including pathogens) in the different compartments of these systems. To better understand the diversity and functionality of microbial …

Intensity Of Linkedin Usage By “Truly Small” Firms To Promote Business-To-Professional Interactions, Lisa Witzig, Joe Spencer, Nikole Maki

AMTP Proceedings 2014

LinkedIn is the largest business-oriented collaborative tool enabling Professional-to-Professional (P2P) and Business-to-Professional (B2P) connections. Regardless of organizational type, there are distinct advantages for firms to utilize LinkedIn. This research builds on previous work examining the intensity of LinkedIn usage by organizational type -- Fortune 200, INC 200, Fortune 200 Non-profits – by focusing on truly small businesses and small non-profits with revenues between $500K to $2M revenue. The study of approximately 1000 organizations finds that truly small non-profits and small businesses utilize the B2P features of LinkedIn significantly less than all three types of larger organizations. This paper applies a …

Rugby As A Growth Model For College Marketing, Nicolas P.E Whitrow, Justin M. Hickey, James W. Satterfield, Michael G. Godfrey

AMTP Proceedings 2014

The purpose of this paper is to suggest a model for institutions to structure their rugby program in order to grow the brand name of an educational institution. The strategy outlined in the paper promotes the use of the sport of rugby union to reach foreign markets that are otherwise not tapped. The international branding of U.S colleges generates source of funding and institutional recognition. A suggested model that could be transposed to other non-school sponsored sports in order to reach the intended market, is preceded by a brief outline and examination of the current common structuring that institutions use …

A Quantitative Analysis Of The Impact Of Wind Energy Penetration On Electricity Prices In Ireland, Micheal O'Flaherty, Niall Riordan, Noel O'Neill, Ciara Ahern

Articles

The maturity of wind technology combined with availability of suitable sites means Ireland is on course to generate 40% of its electricity from the wind by 2020.This work sets out to quantify, to what degree, if any, increased wind penetration translates into reduced wholesale and retail prices for electricity. The consensus from the literature is that increasing wind penetration reduces wholesale electricity prices, but views vary as to what degree this translates into reduced retail prices for the consumer.

This work demonstrates the effect of wind energy penetration on the price of electricity in Ireland using quantitative data from the …

Semantic Model And Updated Screening Criteria For Polymer Flooding, Laila Dao Saleh

Doctoral Dissertations

"Enhanced oil recovery (EOR) processes produce oil that conventional methods leave behind, where interfacial forces, heavy oil viscosity, and reservoir heterogeneity make it difficult to produce. Many EOR methods are available but usually cannot be used at the same time for a candidate reservoir. Therefore, it is important to select the most appropriate EOR process from among the possible techniques. EOR screening criteria have been created using EOR datasets and serve as the first step to compare the suitability of each technique for a specific reservoir. Most of these datasets are based on field data collected from EOR surveys published …

Automated Classification Of Malignant Melanoma Based On Detection Of Atypical Pigment Network In Dermoscopy Images Of Skin Lesions, Nabin K. Mishra

Doctoral Dissertations

“Melanoma causes more deaths than any other form of skin cancer. Early melanoma detection is important to prevent progression to a more deadly stage. Automated computer-based identification of melanoma from dermoscopic images of skin lesions is the most efficient method in early diagnosis. An automated melanoma identification system must include multiple steps, involving lesion segmentation, feature extraction, feature combination and classification. In this research, a classifier-based approach for automatically selecting a lesion border mask for segmentation of dermoscopic skin lesion images is presented. A logistic regression based model selects a single lesion border mask from multiple border masks generated by …

Biomineralization Of Carbonates In Modern Microbial Sediments And Its Implications For Co₂ Sequestration, Varun Gnanaprian Paul

Doctoral Dissertations

"Several bacterial species influence carbonate mineral precipitation by modifying pH, alkalinity, Ca²⁺ activity and by providing nucleation sites for mineralization. Two studies have been undertaken to explore microbial influence in the mineralization of carbonates. In the first study, the ability of sulfate-reducing bacteria (SRB) to induce carbonate mineralization was investigated as a means to enhance mineral sequestration of CO₂. Sulfate-reducing bacteria enriched from hypersaline Storr's Lake, The Bahamas; Lake Estancia, New Mexico; and Great Salt Plains Lake, Oklahoma, were tested in reactors under varying CO₂ concentrations. Carbonate mineral precipitation was achieved only in reactors with Lake Estancia SRB community and …

Elevated Temperature Mechanical Properties Of Zirconium Diboride Based Ceramics, Eric W. Neuman

Doctoral Dissertations

"Research presented in this dissertation focused on the mechanical behavior of ZrB₂ based ceramic at elevated temperatures. Flexure strength, fracture toughness, and elastic modulus were measured at temperatures up to 2300ºC for three compositions: monolithic ZrB₂ (Z); ZrB₂ - 30 vol% SiC - 2 vol% B₄ C (ZS); and ZrB₂ - 10 vol% ZrC (ZC). In argon, Z, ZS, and ZC had strengths of 210 (at 2300ºC), 260 (at 2200ºC), and 295 MPa (at 2300ºC), the highest temperatures tested for each composition. Fractography was used extensively to characterize the strength limiting flaws as a function of temperature. Strength of ZS …

Investigation Of Fluids Flow Behavior In Nano-Scale Channels By Using Optic Imaging System, Qihua Wu

Doctoral Dissertations

"Tight gas and shale gas reservoirs are characterized to have small pores with diameters in nanometer (nm) range. The physics of fluid flow in nanopores is poorly understood. Knowing the fluid flow behavior in the nano-range channels is of major importance for stimulation design, gas production optimization and calculations of the relative permeability of gas in tight shale gas systems. In this work, a lab-on-chip approach for direct visualization of the fluid flow behavior in nano-scale channels was developed using an advanced epi-fluorescence microscopy method combined with a nano-fluidic chip. The nanofluidic chips with different dimensions were designed and fabricated. …

Graphite Aerogels And The Formation Mechanism Of Unusual Micron-Sized Rod And Helical Structures, Clarissa Ann Wisner

Doctoral Dissertations

"Pyrolysis at 800 ºC under argon has shown that polyimide (PI), polyacrylonitrile (PAN), polydicyclopentadiene (DCPD) and polybenzoxazine (PBO) aerogels are all viable alternatives to traditional resorcinol-formaldehyde (RF) aerogels as precursors to amorphous carbon aerogels. Subsequent high temperature pyrolysis at 2300 ºC of such carbon aerogels under helium has shown that amorphous carbon from PI and PBO yields the highest degree of graphitization, whereas from RF aerogels yields the lowest.

Those two types of graphite aerogels include also a high concentration of micron-size columnar and helical (screw-like) structures, whose formation is favored by macroporosity and high nitrogen retention in the 800 …

Seismic Anisotropy And Mantle Flow Beneath Africa And Arabia, Ahmed Abdalla Elsheikh

Doctoral Dissertations

"In spite of numerous studies, the mechanisms for the rifting, uplifting, and volcanism on the African plate remain enigmatic. The most popular hypotheses proposed for explaining these tectonic phenomena involve edge-driven small-scale mantle convection and the thermal or dynamic effects of one or more mantle plumes. In this study we use continental scale shear-wave splitting (SWS) measurements to provide additional constraints on the various models of rifting, uplifting, and volcanism of the Cameroon Volcanic Line (CVL) and the Arabian plate. The splitting of P-to-S converted phases at the core-mantle boundary on the receiver side (XKS including PKS, SKKS, and SKS) …

Synthesis Of Radioactive And Nonradioactive Nanostructures Through Radiolytic And Wet Chemistry, Jessika Viviana Rojas Marin

Doctoral Dissertations

"In this work the synthesis of non radioactive and radioactive nanoparticles (NPs) through radiolytic and wet chemistry was studied. Non radioactive NPs of rhenium, iridium, and rhodium were synthesized from aqueous solutions containing the metal salt precursors by gamma irradiation. The solutions were irradiated to generate reducing species that led to the nucleation and growth of the nanoparticles. Amorphous rhenium oxide nanoparticles with average sizes ranging from 10 nm to 55 nm were obtained. Metallic iridium and rhodium nanoparticles were produced in polyvinyl-pyrrolidone (PVP) having narrow particle size distributions and average particle sizes from 2 nm to 6 nm. The …

Turbo Equalization For Multiple-Input Multiple-Output (Mimo) Wireless Communication Systems, Longbao Wang

Doctoral Dissertations

"This dissertation investigates both of the frequency domain and time domain turbo equalization with multiple-input multiple-output (MIMO) fading channels for radio frequency and underwater acoustic communications. First, a low complexity frequency domain turbo equalization (FDTE) is proposed for the MIMO systems with zero padding (ZP) or cyclic prefix (CP) inserted between the transmitted data blocks and its performance is tested on the real-world UWA communications experiments.

Second, as high speed communication system requires efficient bandwidth usage and power consumption, CP or ZP is not transmitted as auxiliary information. An inter-block interference cancelation and CP reconstruction algorithm is developed to re-arrange …

Maximum Crosstalk Estimation And Modeling Of Electromagnetic Radiation From Pcb/High-Density Connector Interfaces, Matthew Scott Halligan

Doctoral Dissertations

"This dissertation explores two topics pertinent to electromagnetic compatibility research: maximum crosstalk estimation in weakly coupled transmission lines and modeling of electromagnetic radiation resulting from printed circuit board/high-density connector interfaces. Despite an ample supply of literature devoted to the study of crosstalk, little research has been performed to formulate maximum crosstalk estimates when signal lines are electrically long. Paper one illustrates a new maximum crosstalk estimate that is based on a mathematically rigorous, integral formulation, where the transmission lines can be lossy and in an inhomogeneous media. Paper two provides a thorough comparison and analysis of the newly derived maximum …

Identifying And Overcoming The Barriers To Sustainable Construction, Cristin Szydlik

Doctoral Dissertations

"Sustainable construction has become increasingly more prevalent over the last decade. All federal and most state government buildings are mandated to achieve Leadership in Energy and Environmental Design (LEED) certification (at the silver level at a minimum). Although sustainable construction is increasingly more common, there are still barriers to the successful completion of a sustainable project, specifically with regards to projects achieving LEED certification. There are still holes in the guidance on how to successfully achieve LEED certification. Even though government agencies have mandated LEED certification, the existing barriers are preventing buildings from achieving certification, which can delay the building …

Emission Source Microscopy For Electromagnetic Interference Source Localization, Pratik Rajesh Maheshwari

Doctoral Dissertations

"For complex and large systems with multiple sources, it is often difficult to localize the sources of radiation. Near-field electromagnetic scanning is used often for root-cause diagnosis by determining field distribution close to the PCB. In the near-field, the evanescent waves are dominant, which may lead to the misinterpretation of them being the dominant sources contributing to the far-field. Another limitation of near-field scanning is that the probe may not be able to access all locations near the PCB due to the complex geometry and high component density. Two-dimensional synthetic aperture radar is a well-known technique used for antenna diagnostic …

Plant Uptake Of Environmental Contaminants: Applications In Phytoscreening, Matthew Alan Limmer

Doctoral Dissertations

"Plants interact directly with their surroundings, extracting nutrients and water from the subsurface to support growth and development of the plant. Through the roots, plants also exude and uptake numerous chemicals. Many of the pathways can also be used by environmental contaminants to be translocated to above ground plant tissues. Such uptake of contaminants has proven useful in remediation and phytoscreening - the use of plants to delineate contaminant plumes. Sampling of trees at contaminated field sites has been used to identify areas of groundwater contaminated with a variety of chlorinated solvents. The use of plants as contaminant biosensors requires …

Phosphate-Doped Borosilicate Enamel Coating Used To Protect Reinforcing Steel From Corrosion, Xiaoming Cheng

Doctoral Dissertations

"Phosphate-doped sodium borosilicate glasses were developed for enamel coatings to provide corrosion protection for reinforcing steel in concrete. Phosphates have low solubilities in borosilicate glasses, generally less than about 4 mol%, and are incorporated mainly as isolated PO₄^3- and P₂O₇^4- anions, along with some borophosphate bonds. With the addition of P₂O₅, the silicate network is repolymerized and tetrahedral borates are converted to trigonal borates, because the phosphate anions scavenge sodium ions from the borosilicate network. The addition of Al₂O₃ significantly increases the solubility of P₂O …

Modeling And Estimation Of Crosstalk Across A Channel With Multiple, Non-Parallel Coupling And Crossings Of Multiple Aggressors In Practical Pcbs, Arun Reddy Chada

Doctoral Dissertations

"In Section 1, the focus is on alleviating the modeling challenges by breaking the overall geometry into small, unique sections and using either a Full-Wave or fast equivalent per-unit-length (Eq. PUL) resistance, inductance, conductance, capacitance (RLGC) method or a partial element equivalent circuit (PEEC) for the broadside coupled traces that cross at an angle. The simulation challenge is resolved by seamlessly integrating the models into a statistical simulation tool that is able to quantify the eye opening at BERs that would help electrical designers in locating crosstalk sensitive regions in the high speed backplane channel designs.

Section 2 investigates the …

Effect Of Solid Solutions And Second Phases On The Thermal Conductivity Of Zirconium Diboride Ceramics, Gregory John Kenneth Harrington

Doctoral Dissertations

"The research presented in this dissertation is focused on the thermal conductivity (k) of ZrB₂ ceramics. The goal was to develop a better understanding of how various solid solutions and second phases affect the thermal and electrical transport in ZrB₂, with a focus on the effect of C, W, and ZrC. The first study showed C additions improved densification and it was proposed that the reduction of boria was the impetus for this result. Boron carbide was formed by the reaction of excess C with reduced B and its formation was mitigated by the addition of ZrH …

Study And Pilot Test On A Novel Eor Method - Coupling Ppg Conformance Control And Surfactant Flooding, Farag Awadh Muhammed

Doctoral Dissertations

"The interest in enhanced oil recovery (EOR) methods has re-emerged in recent years; however, significant challenges remain for the widespread deployment of these methods. One major downside to the successful application of EOR technologies in mature reservoirs is conformance problems (e.g. heterogeneity). To mitigate these problems, a novel EOR method which couple preformed particle gel (PPGs) conformance treatment with traditional surfactant flooding in one process is introduced.

This dissertation provides a comprehensive study for the proposed method. A series of laboratory tests were carried out to understand the chemical interaction between PPGs and surfactants. A new method to evaluate PPGs …

Energy Aware And Privacy Preserving Protocols For Ad Hoc Networks With Applications To Disaster Management, Mayank Raj

Doctoral Dissertations

"Disasters can have a serious impact on the functioning of communities and societies. Disaster management aims at providing efficient utilization of resources during pre-disaster (e.g. preparedness and prevention) and post-disaster (e.g. recovery and relief) scenarios to reduce the impact of disasters. Wireless sensors have been extensively used for early detection and prevention of disasters. However, the sensor's operating environment may not always be congenial to these applications. Attackers can observe the traffic flow in the network to determine the location of the sensors and exploit it. For example, in intrusion detection systems, the information can be used to identify coverage …

Thermal-Fluid Modeling Of The Missouri S&T Reactor, Susan Maria Sipaun

Doctoral Dissertations

"Thermal-fluid modeling of the Missouri University of Science and Technology Reactor (MSTR) was carried out using a computational fluid dynamics code (CFD), STAR-CCM+. First, a three-dimensional parallel-plate model was developed, and the cosine-shaped heat flux was applied to the MSTR core. Simulation results for fluid flow under natural convection condition show coolant temperature and velocity as a function of core power. A characteristic equation for the parallel-plate model was obtained based on Forchheimer's flow equation. The inertial resistance tensor and viscous resistance tensor were found to be 281005 kg/m^4 and 7121.6 kg/m^3 respectively. The MSTR core was then defined as …

Carbon Dioxide - Heavy Oil Systems: Thermodynamics, Transport And Interfacial Stability, Truynh Quoc My Duy Tran

Doctoral Dissertations

"Conventional oil recovery leaves behind around 67% of original oil in place for light oils and all of it for heavy oils. The carbon dioxide flooding process is the cheapest among the recovery methods for the next stage. The interest here lies in recovering heavy oil. When CO₂ dissolves in oil, it increases the volume of oil, squeezes it out of narrow capillaries and the viscosity of oil drops by up to an order of magnitude. Starting with the available data with and without CO₂ in heavy oil, the free volume theory is used to predict these physical …

Impact Of Slickwater Fracturing Fluid Compositions On The Petrophysical Properties Of Shale And Tightsand, Yongpeng Sun

Doctoral Dissertations

"A tight reservoir always requires hydraulic fracturing before production to increase production rate. The additives in hydraulic fluids are highly considerable for a successful stimulation. A friction reducer is often used to reduce the flowing friction in the wellbore during hydraulic fracturing. Extensive researches have been conducted to examine the extent it can reduce the fluid friction in tubings; however, no research has been reported on its behavior in a reservoir, which is related to the fracture extension. A breaker is also pumped into the formation to degrade the friction reducer. However, it is not clear that what is the …

Cross, Crucifix, Culture: An Approach To The Constitutional Meaning Of Confessional Symbols, Frederick Mark Gedicks, Pasquale Annicchino

Faculty Scholarship

In the United States and Europe the constitutionality of government displays of confessional symbols depends on whether the symbols also have nonconfessional secular meaning (in the U.S.) or whether the confessional meaning is at least absent (in Europe). Yet both the United States Supreme Court (USSCt) and the European Court of Human Rights (ECtHR) lack a workable approach to determining whether secular meaning is present or confessional meaning absent.

The problem is that the government can nearly always articulate a possible secular meaning for the confessional symbols that it uses, or argue that the confessional meaning is passive and ineffective. …