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Biofacies Analysis Of Late Mississippian Ostracodes And Their Use As Paleoenvironmental Indicators In The Bluefield Formation, Mercer County, West Virginia, Benjamin T. Stencil Aug 2012

Biofacies Analysis Of Late Mississippian Ostracodes And Their Use As Paleoenvironmental Indicators In The Bluefield Formation, Mercer County, West Virginia, Benjamin T. Stencil

Theses and Dissertations

The Bluefield Formation (Chesterian, Upper Mississippian) of the Appalachian Basin is a lithologically variable unit, composed of mudstones lithofacies with subordinate amounts of sandstone and limestone. By analyzing sedimentology and the prominence of ostracodes, an ostracode biofacies model was generated that provides a large-scale paleoenvironmental framework for the Bluefield Formation. Three ostracode assemblages were defined in an effort to identify environmental conditions during deposition of the Bluefield: Assemblage I - Polytylites Assemblage; Assemblage II - Sansabella Assemblage; and Assemblage III - Whipplella Assemblage. The assemblage distributions indicate that nearshore transitional marine environments were common and normal open marine conditions were …

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Establishment Methods Of Arundinaria Species For Restoration Purposes, David Pierce Russell Aug 2012

Establishment Methods Of Arundinaria Species For Restoration Purposes, David Pierce Russell

Theses and Dissertations

Rivercane, Arundinaria gigantea, is the native woody evergreen grass that has exhibited rapid population decline since European colonization of North America. Agriculture and urban expansion have reduced this important ecosystem type to remnant populations. This poses challenges to current restoration efforts by minimizing genetic diversity and limiting healthy host sites for propagation. Objectives of this research were to test four methods of establishment that would promote the greatest survivability and growth of propagules. Non-irrigated field studies indicated greatest rivercane growth response when planted in increased shade (60 - 85% light reduction). Monthly plantings indicated that February offered the greatest probability …

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Evaluation Of Field-Scale Soil Organic Carbon And Watershed-Scale Bioenergy Crop Production In Mississippi, Sarah Duffy Aug 2012

Evaluation Of Field-Scale Soil Organic Carbon And Watershed-Scale Bioenergy Crop Production In Mississippi, Sarah Duffy

Theses and Dissertations

To date only a limited number of studies have been done at the field level to observe the effects of agricultural management practices on carbon sequestration, water quality, and bioenergy crop yield in Mississippi. Therefore, the goals of this study were to monitor soil organic carbon (SOC) levels at the field scale and perform a comprehensive analysis of the potential environmental impacts at the watershed scale using the Soil and Water Assessment Tool (SWAT) in two watersheds located in Mississippi. It was found that SOC levels generally are affected by depth, land use, and time. The SWAT models showed good …

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Evaluation Of The Hydrologic Impact, Potential Forest Biomass Production, And Sensitivity Analysis Of The Upper Pearl River Watershed Using Swat Model, Sunita Khanal Aug 2012

Evaluation Of The Hydrologic Impact, Potential Forest Biomass Production, And Sensitivity Analysis Of The Upper Pearl River Watershed Using Swat Model, Sunita Khanal

Theses and Dissertations

The Soil and Water Assessment Tool (SWAT) was used to quantify the potential impacts of clearcutting on hydrologic and water quality components, and assess potential forest biomass production and perform sensitivity analysis of crop parameters to predict forest biomass in the Upper Pearl River Watershed. Results based on clearcutting indicated that the hydrologic and water quality components increases with increase in percentage of forest area harvested. The most significant effect was observed from 55% and 75% harvesting scenarios. The results based on SWAT’s performance to simulate potential forest biomass production showed satisfactory performance and revealed that the watershed has the …

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Experimental And Computational Study Of The Ph Dependence Of Dithiopurine (Dtp) Interaction With Gold Nanoparticles (Aunps), Hao Xia Aug 2012

Experimental And Computational Study Of The Ph Dependence Of Dithiopurine (Dtp) Interaction With Gold Nanoparticles (Aunps), Hao Xia

Theses and Dissertations

Understanding molecular level ligand interfacial interaction with gold nanoparticles (AuNPs) is important for AuNP applications such as catalysts, drug delivery vehicles, and so forth. As an organothiol that can undergo multiple tautomerization, protonation and deprotonation reactions, 2,6-dithiopurine (DTP) can have many different structures in solution and on AuNP surfaces. The goal of this research is to determine the structure of DTP on AuNPs at different pHs using a combination of experimental investigation and computational modeling. The experimental DTP UV-vis spectra and the DTP adsorption on AuNPs are pH strongly dependent, indicating the structural complexity of DTP in solution. The DTP …

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Exploiting Spatial And Spectral Information In Hyperdimensional Imagery, Matthew Allen Lee Aug 2012

Exploiting Spatial And Spectral Information In Hyperdimensional Imagery, Matthew Allen Lee

Theses and Dissertations

In this dissertation, new digital image processing methods for hyperdimensional imagery are developed and experimentally tested on remotely sensed Earth observations and medical imagery. The high dimensionality of the imagery is either inherent due to the type of measurements forming the image, as with imagery obtained with hyperspectral sensors, or the result of preprocessing and feature extraction, as with synthetic aperture radar imagery and digital mammography. In the first study, two omni-directional adaptations of gray level co-occurrence matrix analysis are developed and experimentally evaluated. The adaptations are based on a previously developed rubber band straightening transform that has been used …

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Insights Into The Taxonomy And Evolution Within An Orchid, Platanthera Dilatata, Based On Orphometrics And Molecular Markers, Binaya Adhikari Aug 2012

Insights Into The Taxonomy And Evolution Within An Orchid, Platanthera Dilatata, Based On Orphometrics And Molecular Markers, Binaya Adhikari

Theses and Dissertations

Documenting biodiversity, at and below the species level, is a persistently challenging task for biologists. Poor understanding of biodiversity may lead to incorrect interpretations of observed variation. The underlying basis of variation can be understood by quantifying multiple sources of information. Nine morphometric characters and plastid DNA sequences (2511 bps) were quantified in a highly variable orchid species, Platanthera dilatata, to evaluate taxonomy of the three named varieties and to understand patterns of evolution. Three morphological groups, identified in a cluster analysis, were distinct in multiple floral traits. Additionally, the three clusters were consistently genetically divergent as indicated by infrequent …

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Fatigue And Crack-Growth In 7050-T7451 Aluminum Alloy Under Constant- And Variable-Amplitude Loading, Justin Wayne Shaw Aug 2012

Fatigue And Crack-Growth In 7050-T7451 Aluminum Alloy Under Constant- And Variable-Amplitude Loading, Justin Wayne Shaw

Theses and Dissertations

Fatigue and crack-growth tests were conducted on 7050-T7451 aluminum alloy under a wide range of loading conditions. Crack-growth tests were conducted on compact, C(T), specimens under constant-amplitude loading, single-spike overloads, and a simulated aircraft spectrum loading. Fatigue tests were also conducted on single-edge-notch bend, SEN(B), specimens under constant-amplitude loading and three aircraft load spectra. The FASTRAN, life-prediction code, was used to make crack-growth predictions on the C(T) specimens; and to make fatigue-life calculations using a 12-micrometer initial flaw size at the center of the edge-notch on the SEN(B) specimens. The predictions agreed fairly well with most of the tests, except …

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Case Study Of East Mississippi Community College's Plan To Assist The Sara Lee Corporation Employees Due To Plant Closing, Bruce J. Hanson Aug 2012

Case Study Of East Mississippi Community College's Plan To Assist The Sara Lee Corporation Employees Due To Plant Closing, Bruce J. Hanson

Theses and Dissertations

The aim or purpose of this study was to statistically determine whether there were significant differences in obtaining employment and wages after training provided by East Mississippi Community College (EMCC). The training was specifically provided to employees of Sara Lee Corporation, LLC, after the massive layoff when the company closed its plant in West Point, Clay County, Mississippi. The plant, a food-processing entity, had been in continuous operation since 1902 after it was founded by two brothers from Clay County, Mississippi. Data obtained from the Statewide Longitudinal Integrated Workforce Management System, as reported by EMCC and the Mississippi Department of …

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Cellulosic Fiber-Derived Carbon Catalyzed By Iron Oxide Nanoparticles, Wen Che Aug 2012

Cellulosic Fiber-Derived Carbon Catalyzed By Iron Oxide Nanoparticles, Wen Che

Theses and Dissertations

The objective of this research was to study the catalytic graphitization of cellulose fibers coated with iron oxide nanoparticles. Bleached cellulose fibers and iron oxide nanoparticles coated cellulose fibers were pyrolyzed at five elevated temperatures. The crystallographic structures of carbon-encapsulated iron oxide nanoparticles were then investigated by the following techniques: Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Raman Spectroscopy, Transmission Electron Microscopy (TEM), and Selected-Area Electron Diffraction (SAED). The graphitization of cellulosic fibers was enhanced by the presence of iron oxide nanoparticles. Moreover, iron oxide nanoparticles deposited on cellulosic fiber samples pyrolyzed above 800°C produced graphitic structures. TEM and XRD …

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Assessment Of The Lactation Index For Managing White-Tailed Deer Populations, Kamen Lee Campbell Aug 2012

Assessment Of The Lactation Index For Managing White-Tailed Deer Populations, Kamen Lee Campbell

Theses and Dissertations

I analyzed precision and accuracy of lactation data to reflect actual fawn recruitment for various levels of fecundity, neonatal mortality, harvest intensity, and hunter selectivity. I evaluated and developed a correction equation to adjust for harvest date effects on lactation detectability. I compared metrics of site-specific fawn recruitment (e.g., lactation rates, hunter observation fawn-to-doe ratios, and post-season fawn-to-doe ratios) among themselves, and to site-specific indices of carnivore abundance, for 18 properties across Mississippi and Alabama. Accuracy of lactation rates are compromised due to variation at minimal harvest intensity and insensitivity to change in fetal rate or neonatal mortality. Lactation data …

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Fused-Ring Heterocycle Syntheses From Thiazole, Oxazole, Benzoxazole, And Benzothiazole Derivatives And Trifluoroacetylations Of N-Methyl Cyclic Ketene-N,O/S-Acetals: Attempted Syntheses Of Functionalized Polymers From Plant-Derived 5-(Hydroxymethyl)Furfural, Hondamuni Ireshika Chathurani De Silva Aug 2012

Fused-Ring Heterocycle Syntheses From Thiazole, Oxazole, Benzoxazole, And Benzothiazole Derivatives And Trifluoroacetylations Of N-Methyl Cyclic Ketene-N,O/S-Acetals: Attempted Syntheses Of Functionalized Polymers From Plant-Derived 5-(Hydroxymethyl)Furfural, Hondamuni Ireshika Chathurani De Silva

Theses and Dissertations

There are two sections to this research dissertation. Part one includes syntheses of fused-ring heterocycles derived from thiazole, oxazole, benzoxazole and benzothiazole derivatives and trifluoroacetylations of in situ generated N-methyl cyclic ketene-N,O/Sacetals. Attempted functionalized polymer syntheses from plant-derived 5-(hydroxymethyl) furfural are discussed in part two. Three 2-methylthiazoles, 2,4,5-trimethyloxazole, 2-methylbenzoxazole and 2- methyl-benzothiazole were each reacted with benzoyl chloride in acetonitrile/triethylamine to generate benzyl-vinyl esters. Base hydrolysis of these benzyl-vinyl esters formed 2-(heterocyclic)-1-phenylethenols which exist in both ketoenol tautomeric forms. These tautomers were used as starting materials for fused-ring heterocycle syntheses. Each tautomeric pair react with dimethyl acetylenedicarboxylate in methanol giving …

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Slope Stability Analysis Of Spoil Dragline Bench In Lignite Coal Mine, Choctaw County, Mississippi, Maria Laila Jover Aug 2012

Slope Stability Analysis Of Spoil Dragline Bench In Lignite Coal Mine, Choctaw County, Mississippi, Maria Laila Jover

Theses and Dissertations

Spoil pile stability in an open pit coal mine is a common problem and the Red Hills Lignite Mine in Choctaw County is no exception. The mine has had spoil stability problems of their spoil dragline bench since the beginning of their activity in 2002. They have managed to stabilize the conditions by installing prefabricated vertical drains (PVD) to consolidate the layers below the spoil dragline bench, which tended to fail due to an increase in pore water pressure. In this study, the capability of analyzing and predicting future pore water pressure conditions is examined. With the use of the …

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Spatial Pattern Of Yield Distributions: Implications For Crop Insurance, Francis Annan Aug 2012

Spatial Pattern Of Yield Distributions: Implications For Crop Insurance, Francis Annan

Theses and Dissertations

Despite the potential benefits of larger datasets for crop insurance ratings, pooling yields with similar distributions is not a common practice. The current USDA-RMA county insurance ratings do not consider information across state lines, a politically driven assumption that ignores a wealth of climate and agronomic evidence suggesting that growing regions are not constrained by state boundaries. We test the appropriateness of this assumption, and provide empirical grounds for benefits of pooling datasets. We find evidence in favor of pooling across state lines, with poolable counties sometimes being as far as 2,500 miles apart. An out-of-sample performance exercise suggests our …

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Spotted Fever Group Rickettsiae, Rickettsia Parkeri And "Candidatus Rickettsia Andeanae", Associated With The Gulf Coast Tick, Amblyomma Maculatum Koch, Flavia Araujo Girao Ferrari Aug 2012

Spotted Fever Group Rickettsiae, Rickettsia Parkeri And "Candidatus Rickettsia Andeanae", Associated With The Gulf Coast Tick, Amblyomma Maculatum Koch, Flavia Araujo Girao Ferrari

Theses and Dissertations

The public health and veterinary importance of Gulf Coast ticks, Amblyomma maculatum Koch (1844) have become more apparent during the last several decades. In addition, new records of this three-host ixodid tick presently show a geographic distribution throughout much of the southern United States. Rickettsia parkeri, a spotted fever group rickettsia (SFGR) that is commonly found infecting the Gulf Coast tick, was only recently recognized as a human pathogen. Over the last decade, more than 20 human cases of disease caused by R. parkeri have been recognized in the Americas, all of which were similar in presentation to mild Rocky …

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Sustainable Construction Practices Of Intentional Communities: A Pilot Investigation In Loudoun County, Virginia And Frederick County, Maryland, Jason Lee Shedd Aug 2012

Sustainable Construction Practices Of Intentional Communities: A Pilot Investigation In Loudoun County, Virginia And Frederick County, Maryland, Jason Lee Shedd

Theses and Dissertations

This project investigated the sustainability of homes within three intentional communities. Semi-structured interview and photographic walkthroughs examined the variability of architectural and technological approaches toward sustainability. These include: passive solar design, green roofs, radiant flooring, composting toilets, ground assist heat pumps, solar water heaters, multiamily units and modular construction. It was hypothesized that variation in sustainable construction is related to socioeconomic status and that economics would be a constraint. This project investigated whether communities were transmitting their practices to wider society, if individuals were copying vernacular architecture and if architectural practices followed individual beliefs regarding sustainability. It was found that …

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Synthesis, Characterization, And Catalytic Activity Of Silica Supported Homo- And Heterodinuclear Metal Complexes, Ankadage Samantha Ranaweera Aug 2012

Synthesis, Characterization, And Catalytic Activity Of Silica Supported Homo- And Heterodinuclear Metal Complexes, Ankadage Samantha Ranaweera

Theses and Dissertations

Stable dinuclear complexes bis(heptane-2,4,6-trionato)dicopper(II) [Cu2(daa)2], bis(1,5-diphenyl-1,3,5-pentanetrionato)dicopper(II) [Cu2(dba)2], bis(1,5-diphenyl-1,3,5-pentanetrionato)dicobalt(II) [Co2(dba)2], and [6,11-dimethyl-7,10-diazahexadeca-5,11-diene-2,4,13,15-tetranato(4-)-N7N10O4O13;O2O4O13O15] copper(II)cobalt(II) [(CuCo(daaen)] were supported on Cab-O-Sil by the batch impregnation technique. The supported samples were characterized by UV-Vis, elemental analysis, X-ray powder diffraction (XRD), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and thermal gravimetric analysis (TGA). Elemental analysis and TGA data confirm that the Cu2(daa)2 complex loses one of its coordinated ligands upon adsorption onto silica in THF at greater than 4.43 wt% Cu loading. By contrast, at all Cu loadings the Cu2(dba)2 complex was adsorbed on the silica surface in CH2Cl2 without loss of ligand. XRD and DRIFTS …

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Rejection, Rumination, And Revenge: A Test Of The Relational Goal Pursuit Theory Of Stalking Perpetration, Benjamin A. Fay Aug 2012

Rejection, Rumination, And Revenge: A Test Of The Relational Goal Pursuit Theory Of Stalking Perpetration, Benjamin A. Fay

Theses and Dissertations

Applying Relational Goal Pursuit Theory (RGT), the present study examined the motivations for obsessive relational intrusion (ORI). Participants (n = 509) were randomly assigned to conditions that 1) primed relational or retaliatory goals, then 2) exposed to a negative romantic relationship vignette (relationship disappointment vs. explicit rejection vs. “nice” rejection), and 3) then were either induced to ruminate about the vignette events or were not. Participants reported how likely they would be to think about pursuit (e.g., frequent calls) and aggressive (e.g., threats) ORI. Contrary to expectations, rejection elicited less ORI than the relationship disappointment condition. However, it was found …

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Remote Sensing Of Cyanobacteria In Turbid Productive Waters, Sachidananda Mishra Aug 2012

Remote Sensing Of Cyanobacteria In Turbid Productive Waters, Sachidananda Mishra

Theses and Dissertations

Cyanobacterial algal bloom is a major water quality issue in inland lakes, reservoirs, and estuarine environments because of its scum and bad odor forming and toxin producing abilities. Health risks from cyanobacterial toxin can vary from skin irritations to fever, intestinal problems, and neurological disorders. Terminations of blooms also cause oxygen depletion leading to hypoxia and widespread fish kills. Adding to the problem, many species of cyanobacteria produce odorous compounds such as geosmin and 2-methylisoborneol (MIB) that cause “earthy-muddy” and “musty” odor in drinking water, which is also a serious issue in aquaculture and drinking water industry. Therefore continuous monitoring …

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Principals' Perceptions Of Factors Associated With The Implementation Of School Wellness Policies, Melissa Davis Aug 2012

Principals' Perceptions Of Factors Associated With The Implementation Of School Wellness Policies, Melissa Davis

Theses and Dissertations

Approximately 1/3 of the children in the United States are overweight or obese. Children in Mississippi have the highest rate of obesity among all other states. The outcome of this epidemic presents an increase in poor health. To address the problems associated with overweight and obesity among children, schools in the U.S. were required to develop school wellness policies. School principals were identified as key individuals in overseeing the development and implementation of the policies. Existing research studies show a strong relationship or association between student health and academic achievement. The purpose of this research study was to investigate elementary …

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Price Pass-Through In U.S. Gasoline Markets, Phillip Anthony Mixon Aug 2012

Price Pass-Through In U.S. Gasoline Markets, Phillip Anthony Mixon

Theses and Dissertations

The price pass-through relationship of retail gasoline markets in the United States has been examined on several levels. This dissertation takes two unique approaches to examine the pass-through behavior (1) a seemingly unrelated regressions model to survey regional differences in gasoline markets and (2) a pooled panel error-correction approach to analyze the effects of spatial competition on local Mississippi gasoline markets. The first model showed the presence of rockets and feathers on a regional level in the US. Moreover, every PADD had a long run asymmetric price pass-through relationship. I included variables to capture the effect of Hurricane Katrina. The …

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Physical Activity And Fruit And Vegetable Consumption Habits In College Student Smokers, Social Smokers, And Nonsmokers, Timothy Chad Murphy Aug 2012

Physical Activity And Fruit And Vegetable Consumption Habits In College Student Smokers, Social Smokers, And Nonsmokers, Timothy Chad Murphy

Theses and Dissertations

Smoking, physical activity, and insufficient fruit and vegetable consumption have been linked to increased instances of coronary heart disease, stroke, peripheral vascular disease, chronic obstructive lung disease, type 2 diabetes, osteoporosis, depression, hypertension, numerous cancers, and complications surrounding blood pressure and blood cholesterol. In the United States approximately 22% of college students have smoked at least one cigarette in the past 30 days; 70-85% are not meeting recommended levels of physical activity; and 75% are not consuming recommended levels of fruits and vegetables. The purpose of this study was to investigate differences in physical activity and fruit and vegetable consumption …

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Impact Of Sodium Lactate And Acetic Acid Derivatives On The Quality Of Fresh Italian Pork Sausage Links, Courtney Alissa Crist Aug 2012

Impact Of Sodium Lactate And Acetic Acid Derivatives On The Quality Of Fresh Italian Pork Sausage Links, Courtney Alissa Crist

Theses and Dissertations

Sodium lactate and acetic acid derivatives were evaluated for their impact on fresh Italian pork sausage links using commercial pork trimmings. Treatments included: 2.5% acetic acid (48.5%) –sodium lactate mixture (51.5%) (V), 2.5% sodium lactate (60% solids) (S), control –0.02% BHA/BHT (B) and negative control –seasoning only (C). Analysis over storage included total plate count (TPC), oxidative rancidity (TBARS), sensory analysis (descriptive and consumer), cooking loss, pH, and color. The S and V treatments had lower TPC (P<0.05) from days 5 through 14 when compared to B and C. TBARS values increased (P<0.05) for treatments C, S, and V while B was did not change (P>0.05) over time. While CIE a* surface values for redness generally decreased over time for all treatments, treatment B maintained more redness …

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In Vitro Catalytic Activity And Inhibition Study Of Prnb From Burkholderia Ambifaria, Qi Ge Aug 2012

In Vitro Catalytic Activity And Inhibition Study Of Prnb From Burkholderia Ambifaria, Qi Ge

Theses and Dissertations

PrnB is a heme-containing enzyme, which catalyzes the ring rearrangement reaction of 7-chlorotryptophan to produce 3-(3-Chloro-2-nitrophenyl)pyrrole. This thesis describes the initial isolation and characterization of PrnB, the second enzyme associated with the pyrrolnitrin biosynthetic pathway in Burkholderia ambifaria. Additionally, alternative peroxidase reactivity was used to study how amino-acids bind to the substrate binding pocket of PrnB. The peroxidase activity of PrnB was measured using three different peroxidase activity assays at various pH values. The peroxidase data was compared to similar studies with the classic peroxidase, Horseradish peroxidase (HRP). Generally, PrnB showed weak peroxidase reactivity. However this weak reactivity was an …

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Influence Of Fresh And Processed Tannic Acid, And Fresh Tannic Acid, And Fresh Tannic Acid Plus Phosphate On Catfish Fillet Color, Microbial Shelf Life And Oxidation, Guilherme Filizzola Cury Aug 2012

Influence Of Fresh And Processed Tannic Acid, And Fresh Tannic Acid, And Fresh Tannic Acid Plus Phosphate On Catfish Fillet Color, Microbial Shelf Life And Oxidation, Guilherme Filizzola Cury

Theses and Dissertations

Fresh tannic acid (5%) (FTA), heated to 121C for 15 min (PTA), and the combination of FTA and phosphates (FPH) were vacuum tumbled with catfish fillets and compared to water tumbled fillets (CTL). Fillets treated with FTA or PTA had higher whiteness whereas all treated fillets had higher chroma values than CTL, resulting in a deeper yellow color fillet. Microbial shelf life (CTL, log CFU/g, APC) of FTA and PTA treated fillets was extended by two days, to11.8 d at 4C, but FPH fillets did not reach over 5 log CFU/g for 15 d of storage. Fat from FTA and …

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Adaptive Traction, Torque, And Power Control Strategies For Extended-Range Electric Vehicles, Brian Patrick Benoy Aug 2012

Adaptive Traction, Torque, And Power Control Strategies For Extended-Range Electric Vehicles, Brian Patrick Benoy

Theses and Dissertations

Modern hybrid electric and pure electric vehicles are highly dependent on control algorithms to provide seamless safe and reliable operation under any driving condition, regardless of driver behavior. Three unique and independently operating supervisory control algorithms are introduced to improve reliability and vehicle performance on a series-hybrid electric vehicle with an all-wheel drive all-electric drivetrain. All three algorithms dynamically control or limit the amount of torque that can be delivered to the wheels through an all-electric drivetrain, consisting of two independently controlled brushless-direct current (BLDC) electric machines. Each algorithm was developed and validated following a standard iterative engineering development process …

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Addressing Sample Bias And Representativeness At The Kinlock Site (22su526) A Freshwater Mussel Shell Ring In The Mississippi Delta, Joseph Alan Mitchell Aug 2012

Addressing Sample Bias And Representativeness At The Kinlock Site (22su526) A Freshwater Mussel Shell Ring In The Mississippi Delta, Joseph Alan Mitchell

Theses and Dissertations

Applied zooarchaeology provides baselines which can be used in modern conservation biology to better understand how faunal communities have changed over time. This goal can only be accomplished, however, by first accounting for the multiple biases present within the archaeological record, and how they may affect sample representativeness. Taxonomic analysis was conducted on freshwater mussel shell from the late prehistoric (ca. A.D. 700 - 1200) Kinlock site, Sunflower County, Mississippi. Species-area curves and biodiversity indices demonstrate that random sampling of surface clusters of shell, up to about 4,000 valves, provides an adequate picture of the overall surface assemblage. Comparison of …

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Alternate Stable States In Ecological Systems, Sarath Sasi Aug 2012

Alternate Stable States In Ecological Systems, Sarath Sasi

Theses and Dissertations

In this thesis we study two reaction-diffusion models that have been used to analyze the existence of alternate stable states in ecosystems. The first model describes the steady states of a logistic growth model with grazing in a spatially homogeneous ecosystem. It also describes the dynamics of the fish population with natural predation. The second model describes phosphorus cycling in stratified lakes. The same equation has also been used to describe the colonization of barren soils in drylands by vegetation. In this study we discuss the existence of multiple positive solutions, leading to the occurrence of S-shaped bifurcation curves. We …

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The Analysis Of The Expression And Phenotype Of The At3g02400 Gene In Arabidopsis Thaliana, Will Gray Aug 2012

The Analysis Of The Expression And Phenotype Of The At3g02400 Gene In Arabidopsis Thaliana, Will Gray

Theses and Dissertations

The involvement of several genes in DNA repair in animals and bacteria, and the induced expression of At3G02400 by Mitomycin C, suggest that this gene is involved in DNA repair in plants. I have tested this hypothesis by studying the regulation of its expression and identifying the function of this gene. To study the expression of this gene, I used a reporter line and bio-computing tools. To identify the function of the gene, I have isolated two T-DNA mutants and screened Targeting Induced Local Lesions in Genomes (TILLING) mutants. T-DNA mutagenesis is the process of inserting transfer DNA into the …

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The Effect Of Slope And Media Depth On Growth Performance Of Sedum Species In A Green Roof System In Mississippi's Sub-Tropical Climate, Sinan Kordon Aug 2012

The Effect Of Slope And Media Depth On Growth Performance Of Sedum Species In A Green Roof System In Mississippi's Sub-Tropical Climate, Sinan Kordon

Theses and Dissertations

In recent years, green roofs have become an accepted solution in ecological urban design to mitigate the impacts of impervious surfaces (Berghage, Beattie, Jarrett, Thuring, & Razaei, 2009). An experimental research project was conducted at the Mississippi Agriculture and Forestry Experiment Station (MAFES) Green Infrastructure Research Area at South Farm of Mississippi State University to determine how medium depth and slope gradient on rooftops affect plant cover and survival. Plant cover was monitored monthly by photographing the experimental green roof platforms. Photoshop and AutoCAD software programs were employed to digitize and to calculate plant cover from the images. All recorded …

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