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Molecular And Proteomic Analysis Of Components Involved In Abscisic Acid (Aba) Signaling Network, Jie Song

Theses and Dissertations

Abscisic acid is an important plant hormone in the responses to biotic and abiotic stresses, which also regulates various growth and developmental processes in plants. Three major components-receptors (PYRs), the PP2C type phosphatases and the SnRK2 subtype kinases form a double negative regulatory system: PYR/PYL/RCARs inhibit the activity of PP2Cs while PP2Cs inhibit that of SnRK2s in ABA signaling pathway. The results of my studies showed that ABA would directly affect the interaction between SnRK2.2 and ABI1 in absence of PYRs. Furthermore, ABA can inhibit the catalytic activity of the SnRK2.2 kinase. These findings indicated that ABA may directly interact …

Sugihara Causality Analysis Of Scalp Eeg For Detection Of Early Alzheimer's Disease, Joseph C. Mcbride, Xiaopeng Zhao, Nancy B. Munro, Greg A. Jicha, Frederick A. Schmitt, Richard J. Kryscio, Charles D. Smith, Yang Jiang

Sanders-Brown Center on Aging Faculty Publications

Recently, Sugihara proposed an innovative causality concept, which, in contrast to statistical predictability in Granger sense, characterizes underlying deterministic causation of the system. This work exploits Sugihara causality analysis to develop novel EEG biomarkers for discriminating normal aging from mild cognitive impairment (MCI) and early Alzheimer's disease (AD). The hypothesis of this work is that scalp EEG based causality measurements have different distributions for different cognitive groups and hence the causality measurements can be used to distinguish between NC, MCI, and AD participants. The current results are based on 30-channel resting EEG records from 48 age-matched participants (mean age 75.7 …

General Education Teachers Implementing Common Core With Students In Special Education: A Mixed Methods Study Of Teachers' Self-Efficacy Beliefs, Jon Leland Cash

Theses and Dissertations

This embedded mixed method study addresses the problems teachers have reported in believing themselves capable to implement the Common Core State Standards with students in special education. This study examines the effect professional development on implementing the Common Core State Standards had on the participating teachers’ self-efficacy beliefs. The participants (N=21) in this study were drawn from a 20-day professional development for teachers based on implementing the Common Core State Standards. The instrument used in the study was the Teacher Efficacy Beliefs System-Self. Data were subject to both statistical and qualitative analysis. The results of this study provide insight into …

Habitat Use Of Shovelnose Sturgeon Scaphirhynchus Platorynchus In The Lower Mississippi River, Patrick Thomas Kroboth

Theses and Dissertations

The habitat requirements of shovelnose sturgeon populations are unknown for the lower Mississippi River. Active acoustic telemetry was used to measure temporal variation in habitat use of shovelnose sturgeon and preference for depth, surface current velocity, and riverbed rugosity and slope by the population and within sandbar microhabitats. Shovelnose sturgeon occupied habitats differently throughout the year; and, within habitats, areas of moderate depth and surface current velocity and smooth riverbed were preferred. Within sandbars, environmental conditions did not differ from the surrounding environment, yet frequent aggregations of individuals in the lower portion of sandbars often in close proximity suggest habitat …

Use Of Natural Antimicrobials To Control Spoilage In Marinara-Type Sauce, Austin R. Abessinio

Theses and Dissertations

Marinara-type sauces were created using three natural antimicrobials, as well as two combination treatments (natamycin, propionic acid, cultured dextrose, natamycin-propionic acid, and natamycin-cultured dextrose) and two controls (sodium benzoate-potassium sorbate, no preservatives). Samples were subjected to a shelf-life study at 20 C with both non-inoculated sauce and sauces that were either inoculated with Zygosaccharomyces bailii or a cocktail of thermophilic fermentative organisms. Natamycin and Natamycin-propionic acid treatments had fewer log colony counts (CFU/g) of yeast and lactic acid bacteria than the negative control after 42 days of storage and performed as well or better than the positive control throughout the …

Survival And Habitat Selection Of American Black Ducks In Tennessee, Kira Cristina Newcomb

Theses and Dissertations

American black duck (Anas rubripes) populations declined throughout North America from 1950–1990, but the breeding population since has stabilized. However, limited information exists on black ducks in the Mississippi Flyway, where wintering populations continue to decline. I radiomarked 111 female black ducks at Tennessee National Wildlife Refuge (TNWR) in winters 2010–2012 to estimate winter survival and investigate patterns of habitat selection. Winter survival (83–85%) was greater than or comparable to previous estimates for black duck populations in North America. Interval survival increased 0.6% with a 100 g increase in body mass, but survival differed between years and waterfowl hunting seasons …

Evaluation Of Herbicide Formulation And Spray Nozzle Selection On Physical Spray Drift, Jasper Lewis Cobb

Theses and Dissertations

New transgenic crops are currently being developed which will be tolerant to dicamba and 2,4-D herbicides. This technology could greatly benefit producers who are impacted by weed species that have developed resistance to other herbicides, like glyphosate-resistant Palmer Amaranth. Adoption of this new technology is likely to be rapid and widespread which will lead to an increase in the amount of dicamba and 2,4-D applied each season. It is well-documented that these herbicides are very injurious to soybeans, cotton, tomatoes, and most other broadleaf crops, and their increased use brings along increased chances of physical spray drift onto susceptible crops. …

Loss Of Thiol Repair Systems In Human Cataractous Lenses, Min Wei, Kui-Yi Xing, Yin-Chuan Fan, Teodosio Libondi, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

PURPOSE. The purpose of this study was to investigate the thiol repair systems of thioltransferase (TTase) and thioredoxin (Trx) and oxidation-damaged proteins in human cataractous lenses.

METHODS. Cataractous lenses in humans (57–85 years of age) were classified into cortical, nuclear, mixed, mature, and hypermature cataract types by using a lens opacity classification system, and were obtained by extracapsular cataract extraction (ECCE) procedure. Cortical and nuclear cataracts were grouped by decreasing order of visual acuity into optical chart reading (R), counting fingers (CF), hand motion (HM), and light perception (LP). ECCE lens homogenate was analyzed for glutathione (GSH) level and enzyme …

Protein-Protein Interaction Profile Of Viral Protein Bicp0 During Bovine Herpesvirus-1 Lytic Infection, Stephanie Elaine Ander

Theses and Dissertations

Bovine Infected Cell Protein 0 (bICP0) is an immediate-early protein encoded by Bovine Herpesvirus-1 that modulates host immune response, activates transcription for all viral promoters, and causes ubiquitin-dependent degradation of proteins. Presented herein is a bICP0 protein-protein interaction (PPI) profile, consisting of 98 cellular and 15 viral proteins, generated through co-immunoprecipitation of bICP0 and its binding partners. The PPI profile was analyzed computationally to identify potential sites of interaction with bICP0 and any cellular pathways that may be influenced by bICP0. Some interactors fall in conjunction with bICP0’s known roles during infection, and others are consistent with known associations of …

Examining Hepatic Steroid Inactivation And Luteal Function Throughout Bovine Pregnancy, Caitlin G. Hart

Theses and Dissertations

The objective of this study was to examine hepatic steroid inactivation and luteal function throughout bovine gestation. In pregnant beef cows, cytochrome P450 3A activity decreased from mid- to late-gestation, while progesterone concentrations tended to increase from mid- to late-gestation. Uridine diphosphate-glucuronosyltransferase activity per kg of body weight was increased in pregnant vs non-pregnant dairy cows. Total corpus luteum (CL) blood perfusion tended to be increased in pregnant vs non-pregnant dairy cows. Hepatic portal blood flow per kg of body weight was increased in pregnant vs non-pregnant dairy cows. Hepatic steroid inactivating enzyme activity, CL blood perfusion, and portal blood …

Who Decides? A Study Of The Effects On Decision Unit Dynamics In Crisis And Crisis Transition, Janet Leigh Drake

Dissertations

Foreign policy decision-making is often an obscured process, particularly when it involves threats to national security or national interests. Despite the lack of transparency, though sometimes necessary, foreign policy decisions can have far-reaching consequences. Policymakers establish and affect relationships with other governments, and can commit state resources for cooperation or for conflict. The purpose of this study is to determine what types of decision units make foreign policy decisions and what factors influence the dynamics of the unit. I employ the decision units (DU) framework developed by Margaret Hermann to decisions made by the United States and Israel during the …

Growth Implant Timing And Effectiveness In Beef Cattle, Herschel Brad Jones

Theses and Dissertations

One hundred crossbred beef steers were used in two experiments to evaluate effects of growth implants on performance. Steers were implanted either at 3.5 months and weaning (CALF); at weaning (WEAN); or not implanted (NONE). In Experiment 1 implanted steers weighed more at weaning (P = 0.01), and had a higher ADG for the entire trial compared to non-implanted steers (P = 0.03). In Experiment 2, at 80 d post wean, implanted steers outweighed NONE (P = 0.09). Overall ADG (P = 0.01) was greater for cattle that were implanted. In the feedlot the CALF group had the lowest ADG …

Effects Of Intercropping Switchgrass In Loblolly Pine Plantations On Bird Communities, Zachary G. Loman

Theses and Dissertations

Intercropping switchgrass (Panicum virgatum) between tree rows within young pine (Pinus spp.) plantations is a novel method to generate lignocellulosic biofuel feedstocks within intensively managed forests. Intensively managed pine supports diverse avian assemblages potentially affected by establishment and maintenance of a biomass feedstock. I sought to understand how establishing switchgrass on an operational scale affects bird communities within intercropped plantations as compared to typical intensively managed loblolly pine (Pinus taeda) plantations. I conducted breeding bird point counts, nest searching and monitoring, and coarse woody debris (CWD) surveys following establishment of intercropped switchgrass stands (6 replicates), traditionally-managed pine plantations, and switchgrass-only …

Effects Of Resveratrol On Post-Thaw Quality Of Stallion Sperm, Kelli Lynn Matheny

Theses and Dissertations

Current equine sperm cryopreservation methods fail to reliably prevent damages to important cellular structures such as the cell membrane and DNA. The objective of this study was to determine the effects of supplementing a stallion semen extender with 1 or 10 mM resveratrol on post-thaw sperm characteristics. Results showed that sperm death was increased with 10 mM compared to both the control and 1 mM (P < 0.05). DNA fragmentation was increased in the 1 mM treatment compared to the control (P < 0.05). ROS activity was reduced the most in the 10 mM with differences between all groups (P < 0.05). Membrane integrity was not different between groups (P > 0.05). Motility of the control was higher than the treatment groups (P < 0.05). Resveratrol was able to reduce ROS but was unable to preserve motility or viability at the concentrations tested.

Efficacy Of An Experiential, In-School Educational Program For Improving Elementary School Students' Attitudes And Knowledge About The Environment, Leslie M. Burger

Theses and Dissertations

Stagnant science achievement by students, greater demands and stresses on natural resources and environmental systems, and societal disengagement from nature highlight the need for education programs to ameliorate subsequent consequences. One attempt to address science performance and environmental apathy is Youth Environmental Science (YES), an environmental education program initiated in 2011 in a rural, minority-dominated, upper elementary school in Mississippi. The program provides five consecutive days (30 hours) of experiential learning in natural sciences. During 2011-2013, I studied cognitive and affective responses of fourth and fifth grade students to YES participation using a pretest-posttest-delayed posttest design. The influence of demographic …

Epidemiological Study Of The Factors That Influence Mortality And Economics On A Commercial Catfish Farm, Fred L. Cunningham

Theses and Dissertations

A Catfish Management Database (CMD) was developed to analyze data from large commercial catfish farms. The CMD was developed so that data collected by the farm could be used for management of the farm and for identifying some of the risk factors associated with important bacteria diseases. This database was designed to 1) to incorporate production data already being recorded for generating reports for use at weekly managerial meetings focused on feeding rates, feed conversion ratios, mortalities and harvesting events 2) be easily used by a catfish farmer to collect management data in order to analyze production efficiency through a …

Evaluation Of Effectiveness, Reproducibility, And Repeatability Of Using Dentition For Estimating Cattle Age, Timothy F. Best

Theses and Dissertations

Study objectives were to determine the effectiveness, reproducibility, and repeatability of dental evaluation for estimating cattle age. Cattle (n = 400) aged 1.5 to 20 yr were evaluated by 3 technicians for estimated age via dentition. A subset (n = 383) was aged again 4 wk later by the same observers. Age estimations were most accurate in YOUNG (< 5 yr old) cattle with at least 95.7% rate of accuracy within 2 yr across all observers and observation events. For MIDDLE (6 to 10 yr old) and OLD (> 10 yr old) cattle, these accuracies were 81.5 and 62.1%, respectively. Reproducibility proved high, with all observers consistently assigning age estimates within 1 yr of one another for more than 9 out of 10 YOUNG animals; all observers agreed on at …

Finite Element Analysis Of Adhesive Bonding Performances Of Wooden Dowel Pin Joints In Furniture, Xin Sun

Theses and Dissertations

This study was performed to investigate how pressure, glue amount, dowel penetration depth and wood grain orientation affect direct withdrawal resistances of dowel pin joints both experimentally and numerically, and develop FE (finite element) models to simulate tensile strength, contact pressure, and shear stress occurred in dowel pin joints. Results indicated that the direct withdrawal resistance load of a dowel pin joints can be predicted based on knowing the glue bonding shear strength between dowel and joint member materials and the pressure between the contact surfaces of the dowel and hole of a connected joint member. The FE contact element …

Biomass And Decomposition Dynamics Of Invasive Chinese Tallow (Triadica Sebifera) In The Southeastern United States, Allison M. Stoklosa

Theses and Dissertations

Recent and anticipated global change has focused concern on the role of forests in ecosystem functioning and carbon sequestration. Of key importance is identifying relevant factors that drive carbon and nutrient dynamics and the consequences of changes in these processes. Systems undergoing invasion by invasive woody species are particularly prone to changes. This study examined the branch and crown biomass and decay dynamics for the invasive Chinese tallow tree in Mississippi, USA as well as the influences of stand and site conditions on biomass modeling and arthropod contributions to fine woody debris decay. Coupling biomass and decay models presents a …

Bounds For The Maximum-Time Stochastic Shortest Path Problem, Anara Bolotbekovna Kozhokanova

Theses and Dissertations

A stochastic shortest path problem is an undiscounted infinite-horizon Markov decision process with an absorbing and costree target state, where the objective is to reach the target state while optimizing total expected cost. In almost all cases, the objective in solving a stochastic shortest path problem is to minimize the total expected cost to reach the target state. But in probabilistic model checking, it is also useful to solve a problem where the objective is to maximize the expected cost to reach the target state. This thesis considers the maximum-time stochastic shortest path problem, which is a special case of …

Associative Nitrogen-Fixing Bacteria And Their Potential To Support The Growth Of Bioenergy Grasses On Marginal Lands, Jayani Jeewanthi Wewalwela

Theses and Dissertations

Rising demands for both food and energy have lifted up the idea of producing renewable biofuels from bioenergy grasses that can companion with associative N2ixing bacteria. Associative N2ixing bacteria can partially fulfill the N requirements of bioenergy grasses enabling successful application for marginal lands. The overall objective of this study was to measure the potential N2ixation of bacteria associated with three bioenergy grasses, giant miscanthus (Miscanthus x giganteus), switchgrass (Panicum virgatum; ‘Alamo’) and energycane (hybrid of Saccharum spontaneum and S. officinarum; HO 02-147) as well as identifying N2ixing bacteria associated with these energy grasses and applying these isolates to grasses …

Computational Methods On Study Of Differentially Expressed Proteins In Maize Proteomes Associated With Resistance To Aflatoxin Accumulation, Alka Tiwari

Theses and Dissertations

Plant breeders have focused on improving maize resistance to Aspergillus flavus infection and aflatoxin accumulation by breeding with genotypes having the desirable traits. Various maize inbred lines have been developed for the breeding of resistance. Identification of differentially expressed proteins among such maize inbred lines will facilitate the development of gene markers and expedite the breeding process. Computational biology and proteomics approaches on the investigation of differentially expressed proteins were explored in this research. The major research objectives included 1) application of computational methods in homology and comparative modeling to study 3D protein structures and identify single nucleotide polymorphisms (SNPs) …

An Approach To Genetic Silencing Of Ricin In Castor (Ricinus Communis L.), Daniel Joseph Barnes

Theses and Dissertations

Castor (Ricinus communis L.) is a high-yielding oilseed crop native to tropical Africa. The seed contains ~60% oil by weight, yielding approximately 1,200 kg of oil per hectare. The oil is composed of ~90% ricinoleic acid, a unique hydroxylatty acid. Its unique composition provides castor oil with distinctive characteristics important for industrial use. Unfortunately, this valuable oilseed has not been widely cultivated in the United States since 1972, due in part to the presence of ricin in the seed. Ricin is a highly toxic lectin found in the endosperm of mature castor seed. This project sought to silence ricin production …

Catalytic Conversion Of Syngas To Higher Alcohols Over Cu-Fe Based Catalysts, Yongwu Lu

Theses and Dissertations

Higher alcohol synthesis (HAS) from syngas or biomass-derived syngas is an important process for the production of oxygenate fuels, fuel additives and other intermediates for valueded chemical feedstock to produce medicine, cosmetics, lubricants, detergents, and polyesters. Chapter I reviews biomass to liquid fuels technology, higher alcohols being used as alternative fuels and fuel additives, the historical perspective and commercial status of higher alcohols, the catalyst system and the reaction mechanism for HAS from syngas. Chapter II discusses the Zn-Mn promoted Cu-Fe based catalyst that was synthesized by the co-precipitation method. The reaction temperature has been tested to study the influence …

Characterization Of Maize Genes In Response To Aspergillus Flavus Infection And Aflatoxin Accumulation, Matthew Constantine Asters

Theses and Dissertations

Aspergillus flavus is a pathogenic fungus causing maize ear rot disease and producing aflatoxins that are carcinogenic to humans and animals. Characterizing maize host resistance mechanisms and prioritizing candidate resistance genes are important to the development of resistant maize germplasm. This study investigated transcriptomics approaches and statistics methods on the identification of maize host resistance genes. Full-length cDNA libraries were also constructed and evaluated for gene cloning and functional analysis. This study established important sources for functional studies on differentially expressed genes and for identification of allelic gene forms to characterize gene polymorphisms and facilitate the development of DNA markers.

Characterization Of Sediment Microbial Communities And Analysis Of Biogeochemical Responses To Eutrophication In Southeastern Estuaries, Gary Alon Blakeney

Theses and Dissertations

Estuaries are valuable economic resources to humans. However, changes in these ecosystems, such as alteration in nutrient availability, can impose eutrophic pressures. Traditionally, estuaries have been monitored through chemical analyses that measure factors such as sediment oxygen demand (SOD) and reduced forms of Fe(II), Mn(II), and H2S. These methods are time consuming and have been proven to be unreliable. This study was conducted to determine if using T-RFLP analysis could be used as a proxy for some of the current methods used to monitor eutrophication. Using SPSS to perform a principle component analysis, it was determined that connections can be …

A Synthetic Approach To The Biflavonoids Chamaejasmine And Isochamaejasmine, Verna B. Baron

Theses and Dissertations

Biflavonoids form a ubiquitous class of compounds in nature, which are well known for their numerous medicinal benefits. Biflavonoids such as chamaejasmine and isochamaejasmine have been shown to exhibit pharmacological activity such as anitidiabetic, anti-malaria, anti- HIV, anticancer etc. Biflavanones, chamaejasmine and isochamaejasmine are dimers of the flavanone narigenin at the C-3 position, which gives them a rare 3/3" C - C linkage. They are structurally similar in that they both have four stereocenters. The difference between these two compounds is the stereochemistry at the C-2" and C-3". In this study, installation of each of these stereocenters will be targeted …

An Examination Of The Predictors Of General Recidivism, Violent Recidivism, And Property Recidivism Among Juvenile Offenders, Megan Suzanne Stubbs-Richardson

Theses and Dissertations

Although studies examining juvenile recidivism have focused primarily on violent recidivism, the factors that predict recidivism likely differ by offense type. To examine general, property, and violent recidivism, this study combined individual-level data (i.e., offender and case characteristics) from the Mississippi Youth Court Information Data System (MYCIDS) for the years 2009-2011 and contextual-level data (i.e., county characteristics) from the 2010 U.S. Census and the 2010 Uniform Crime Reports (UCR). Results showed that offender characteristics predicted only general and property recidivism, but case characteristics mattered for all three types (i.e., general, violent, and property recidivism). Contextual characteristics (i.e., the percentage of …

Aspects Of The Ecology And Management Of Mottled Ducks In Coastal South Carolina, James Claybourne Shipes

Theses and Dissertations

Mottled ducks (Anas fulvigula) are endemic to Gulf Coastal United States and Mexico. Birds from Florida, Louisiana, and Texas were released in coastal South Carolina from 1975-1983, and banding data suggest an expanding South Carolina population. We radio-marked 116 females in August 2010-2011 in the Ashepoo, Combahee, and Edisto (ACE) Rivers Basin and used radio telemetry to study habitat selection, searched for nests of non-radiomarked females, and conducted indicated breeding pair surveys of mottled ducks at various wetlands. Overall, radiomarked mottled duck females selected managed wetland impoundments, wetlands containing planted corn, and brackish wetlands. Overall nest success of 42 nests …

Investigation Of The Beneficial Effect Of Enterobacter Cloacae Strain Jd6301 On Mice Challenged With Escherichia Coli O157:H7, Jessica Grissett Wilson

Theses and Dissertations

The environment of the gastrointestinal (GI) tract is an extremely complex system made up of not only host cells, but also many beneficial microbes. Disruption of this environment can often lead to disorders and health issues. To help balance this system, probiotics have often been administered to both humans and animals, such as livestock. This study aimed to determine what beneficial effects a novel strain of Enterobacter cloacae, strain JD6301, could offer to a host in the presence of an enteric infection with E. coli O157:H7. Upon administration of JD6301, supplemented animals had overall less E. coli present in the …