Life Sciences Commons^™

The Effects Of Age On Reproduction In A Citrus Root Weevil Diaprepes Abbreviatus, Heather R. Chasez

Electronic Theses and Dissertations

Understanding the factors influencing mate choice is a major focus of sexual selection. Many factors are potentially involved, including age of the individual. The good genes model and the youth advantage model both make predictions about the effect of age on mate choice. Under the good genes model older mates would be the more preferable due to their proven high survivability. The “youth advantage” model, predicts that young to intermediate age males would be more advantageous as mates because of a decrease in sperm quality and the possibility of increased germ-line mutations in older animals. I examined the effects of …

Understanding The Invasion Of Florida's Intertidal Crassostrea Virginica Reefs By Non-Native Marine Invertebrate Species, Ethan Fletcher Nash

Electronic Theses and Dissertations

Predicting the locations of new biological invasions has become a high priority for biologists as well as trying to predict if newly introduced species will become damaging to native ecosystems. Reefs of the eastern oyster Crassostrea virginica in Mosquito Lagoon, Florida have been highly disturbed in recent years resulting in dead reefs (piles of dead, disarticulated shells) some of which have been restored. I conducted oyster reef surveys for non-native invertebrates to determine if disturbance on these oyster reefs might assist invasion by two species, Mytella charruana and Perna viridis, recently introduced to the southeastern coast of the United States. …

Variability Of Carbon Stock In Florida Flatwoods Ecosystems Undergoing Restoration And Management, Kathryn Elizabeth Becker

Electronic Theses and Dissertations

The global community is struggling with mitigating the effects of widespread habitat loss and degradation; the effects of which are being further magnified in the face of global climate change. Quality natural habitat is becoming increasingly limited and atmospheric carbon levels continue to rise. Therefore, land managers responsible for multiuse management are often faced with the dilemma of managing ecosystems for biodiversity, as well as optimizing ecosystem services such as carbon storage and sequestration. However, some management techniques used to meet these objectives may yield conflicting results, specifically, the management tool of prescribed fire. Fire is crucial in maintaining species …

Biophysical Characterization Of The Membrane Binding Domain Of The Pro-Apoptotic Protein Bax, Pranav Garg

Electronic Theses and Dissertations

The BCL-2 family of proteins tightly regulates the delicate balance between life and death. The pore forming Bax is a pro-apoptotic member belonging to this protein family. At the onset of apoptosis, monomeric cytoplasmic Bax translocates to the outer mitochondrial membrane, forms oligomeric pores thereby letting mitochondrial cytochrome c enter the cytosol and initiate the apoptotic cascade. The C-terminal "helix 9" is thought to mediate the membrane binding of BAX. A 20-amino acid peptide corresponding to Bax C-terminus (VTIFVAGVLTASLTIWKKMG) and two mutants where the two lysines are replaced with Glu (charge reversal mutant, EE) or Leu (charge neutralization mutant, LL) …

Impact Of Land Management On House Mice And Red Imported Fire Ants, Jesse R. Abelson

Electronic Theses and Dissertations

Understanding of mechanisms that limit the abundance and distribution of species is central to ecology. The failure of mechanisms to regulate populations can result in population outbreaks. There have been two outbreaks of house mice in the past decade in central Florida. In my study, I examine the efficacy of landscape management in the form of mowing and plowed soil barriers to limit or prevent outbreaks of house mice in a former agricultural area. House mouse populations were highly variable, but were unaffected by mowing or plowed soil barriers. Red imported fire ants were ubiquitous in the study area regardless …

Adaptive Responses Of Branchial Morphology To Hypoxia In The Neotropical Electric Fish Genus Brachyhypopomus, Leilani B. Pathak

Electronic Theses and Dissertations

Many tropical aquatic environments worldwide are characterized by intermittent or prolonged hypoxia (low dissolved oxygen). Nevertheless, many tropical freshwater fishes are able to inhabit these challenging environments via a range of morphological, physiological and behavioral adaptations. Brachyhypopomus is a diverse genus of weakly electric fishes represented by 28 known species distributed from Panama to Argentina. 17 species are restricted to permanently normoxic habitats (blackwater rivers and terra firme streams), eight species are restricted to seasonally or perennially hypoxic habitats (whitewater floodplains of large tropical rivers or permanent swampy habitats), and three species are eurytopic (occur in both seasonally hypoxic and …

Mechanisms Of Alpha]-Synuclein-Induced Neurodegenertaion In Parkinson's Disease And Stroke, Cherine Belal

Electronic Theses and Dissertations

Parkinson’s disease (PD) is a debilitating neurodegenerative disorder affecting one million Americans. Despite its social and economic impact, the pathological cascades that lead to neuron dysfunction and degeneration in PD are poorly understood. Endoplasmic reticulum (ER) stress has been implicated as an initiator or contributing factor in neurodegenerative diseases including PD. The ER is an organelle central to protein folding and intracellular Ca2+ homeostasis. Perturbations of these functions result in ER stress and upregulation of ER stress proteins, of which some have been implicated in counteracting ER stress-induced cell death. The mechanisms that lead to ER stress and how ER …

Expression Of Trichoderma Reesei Beta]-Mannanase In Tobacco Chloroplasts And Its Utilization In Lignocellulosic Woody Biomass Hydrolysis, Pankaj M. Agrawal

Electronic Theses and Dissertations

Lignocellulosic ethanol offers a promising alternative to conventional fossil fuels. One among the major limitations in the lignocellulosic biomass hydrolysis is unavailability of efficient and environmentally biomass degrading technologies. Plantbased production of these enzymes on large scale offers a cost effective solution. Cellulases, hemicellulases including mannanases and other accessory enzymes are required for conversion of lignocellulosic biomass into fermentable sugars. β- mannanase catalyzes endo-hydrolysis of the mannan backbone, a major constituent of woody biomass. In this study, man1 gene encoding β-mannanase was isolated from Trichoderma reesei and expressed via the chloroplast genome. PCR and Southern hybridization analysis confirmed the site-specific …

Stable Expression Of Tuberculosis Vaccine Antigen In Lettuce Chloroplasts, Priya Saikumar Lakshmi

Electronic Theses and Dissertations

Tuberculosis (TB) is caused by Mycobacterium tuberculosis and is one of the leading reasons of death by an infectious bacterial pathogen. The development of TB vaccines has been recognized as a major public health priority by the World Health Organization. In this study, a potential candidate antigen, ESAT-6 (6 kDa early secretory antigenic target) was fused with cholera toxin B subunit (CTB). Transplastomic lettuce plants were generated expressing these fusion proteins. Site-specific transgene integration into the chloroplast genome was confirmed by polymerase chain reaction and Southern blot analysis. In transplastomic leaves, expression levels of fusion protein (CTB-ESAT6) varied depending upon …

Applications Of Airborne And Portable Lidar In The Structural Determination, Management, And Conservation Of Southeastern U.S. Pine Forests, Claudia De Mendonca Costa Synek Listopad

Electronic Theses and Dissertations

Active remote sensing techniques, such as Light Detection and Ranging (LiDAR), have transformed the field of forestry and natural resource management in the last decade. Intensive assessments of forest resources and detailed structural assessments can now be accomplished faster and at multiple landscape scales. The ecological applications of having this valuable information at-hand are still only being developed. This work explores the use of two active remote sensing techniques, airborne and portable LiDAR for forestry applications in a rapidly changing landscape, Southeastern Coastal Pine woodlands. Understanding the strengths and weaknesses of airborne and portable LiDAR, the tools used to extract …

Functional Activation Of Cartilaginous Fish Melanocortin Receptors, Christina Lee Reinick

Electronic Theses and Dissertations

The evolution of the melanocortin receptor (MCR) gene family has been dictated by two genome duplication events (2R hypothesis). The gnathostomes are thus predicted to possess a minimum of four MCR genes. Previous studies on cartilaginous fish have shown evidence for the presence of only three MCRs. The purpose of this thesis is to functionally express the MC5R from the spiny dogfish (Squalus acanthias) and the putative MC2R and MC3R from the elephant shark (Callorhinchus milii); these receptors have not yet been fully characterized. In this study, SacMC5R was able to be expressed in CHO cells …

Altered Calcium Handling In Cerebellar Purkinje Neurons With The Malignant Hyperthermia Mutation, Ryr1-Y522s/+, George C. Talbott

Electronic Theses and Dissertations

To investigate the etiology of malignant hyperthermia and central core disease, mouse models have recently been generated and characterized (Chelu et al., 2006). These RyRY522S/+ knock-in mutant mice provide an excellent tool to investigate calcium dysregulation, its pathological consequences, and potential therapeutic approaches. Skeletal muscle harboring this mutation exhibits calcium leak from internal stores and an increased sensitivity to activation by caffeine, voltage, and temperature (Durham et al., 2008). Although alterations in RyR1 channel function and resultant changes in cellular function have been characterized in skeletal muscle, the effects of MH mutations in RyR1 on central nervous system function have …

Genetic Polymorphisms And The Treatment Outcome In Standard-Risk Pediatric Acute Lymphoblastic Leukemia, Qi Wei

Electronic Theses and Dissertations

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer and accounts for 30 - 35% of all cancers in children. Significant improvement in the treatment of pediatric ALL has been achieved in recent years. Only 50 years ago, the disease was uniformly fatal with an Overall Survival (OS) rate < 5%. Modern-day, multi-drug chemotherapy is associated with an overall survival rate over 80%. Standard-risk ALL comprises the majority of ALL with an overall survival approaching 90%. Despite this success, children who relapse from this disease accounts for the majority of cancer-related deaths in children. The backbone of treatment protocols have incorporated somatic but not host genetic features in the treatment regimens. The current study examined 12 genetic polymorphisms affecting the pharmacodynamics of antileukemic drugs in an attempt to identify biologic markers related to the risk of disease relapse.

In the current research program, 125 standard-risk ALL patients who were treated at The Children's Hospital were enrolled in a retrospective study. Statistical analysis was performed to evaluate the association between genetic polymorphisms and risk of disease relapse in this study cohort. The GSTM1 null genotype was associated with a …

Memory Access Patterns For Cellular Automata Using Gpgpus, James Michael Balasalle

Electronic Theses and Dissertations

Today's graphical processing units have hundreds of individual processing cores that can be used for general purpose computation of mathematical and scientific problems. Due to their hardware architecture, these devices are especially effective when solving problems that exhibit a high degree of spatial locality. Cellular automata use small, local neighborhoods to determine successive states of individual elements and therefore, provide an excellent opportunity for the application of general purpose GPU computing. However, the GPU presents a challenging environment because it lacks many of the features of traditional CPUs, such as automatic, on-chip caching of data. To fully realize the potential …

Micrornas 9a, 9b, 9c And 315 Regulate Expression Of A Reporter For The Neuronal Microtubule-Associated Protein Futsch/Map1b, Leslie M. Rozeboom

Electronic Theses and Dissertations

Fragile X syndrome (FXS) is the most common form of inherited mental retardation in humans. FXS is caused by loss of the Fragile X Mental Retardation Protein (FMRP), an important regulator of neuronal mRNA translation. Patients with FXS display cognitive deficits including memory problems. Protein synthesis-dependent long-term changes in synaptic plasticity are involved in the establishment and maintenance of long-term memory. One prevalent theory of FXS pathology predicts that FMRP is required to negatively regulate the translation of important mRNAs at the synapse. We are investigating microRNAs (miRNAs) as a potential regulator of synaptic FMRP-regulated mRNAs that have previously been …

Acute Synaptic Activity Causes Differential Mirna Expression In The Drosophila Melanogaster Larval Central Nervous System, Robert Ian Sand

Electronic Theses and Dissertations

The primary goal of this thesis was to determine if spaced synaptic stimulation induced the differential expression of microRNAs (miRNAs) in the Drosophila melanogaster central nervous system (CNS). Prior to attaining this goal, we needed to identify and validate a spaced stimulation paradigm that could induce the formation of new synaptic growth at a model synapse, the larval neuromuscular junction (NMJ). Both Channelrhodopsin- and high potassium-based stimulation paradigms adapted from (Ataman, et al. 2008) were tested. Once validation of these paradigms was complete, we sought to characterize the miRNA expression profile of the larval CNS by miRNA array. Following attainment …

Plasma Membrane Dynamics In The Drosophila Embryo, Amelia E. Zommer

Electronic Theses and Dissertations

Convergent extension is a highly conserved process among mammals, in which the tissue narrows in one axis, and extends across another. Tissue elongation is directed by the regulation of cell interface behaviors, which guides cell intercalation and rosette formation. Rosette formation occurs through the contraction of vertically oriented cell interfaces, and the subsequent elongation of new horizontal interfaces. It has been shown that actomyosin-generated tension functions to direct rosette formation. In this thesis, I have tested the function of regulators of F-actin networks, as well as endocytic and exocytic mechanisms, to identify new components that control interface behaviors and cell …

The Effects Of Chronic Prophylactic Naproxen Sodium On Skeletal Muscle Adaptation To Resistance Exercise In Recreationally-Trained College-Aged Males, Christi Brewer

Electronic Theses and Dissertations

Resistance exercise causes exercise-induced muscle injury (EIMI), triggering an acute local inflammatory response associated with delayed-onset muscle soreness (DOMS). DOMS is characterized by a predictable discomfort and decreased level of muscle performance and is believed to be the product of both mechanical and inflammatory processes. From the latter perspective, non-steroidal anti-inflammatory drugs (NSAIDs) have been investigated for their potential to alleviate DOMS-associated symptoms. Such analgesics exert their effects by blocking the formation of prostaglandins; however, prostaglandins, specifically prostaglandin F 2?, also play an important role in skeletal muscle regeneration. While some have advocated the use of NSAIDs for the relief …

Effects Of Tornado Damage, Prescribed Fire, And Salvage Logging On Oak (Quercus Spp.) Saplings In Upland Oak Forests In Northern Mississippi, Jeffery B. Cannon

Electronic Theses and Dissertations

After European colonization and extensive logging folloby long periods of fire suppression, oak dominated forests, woodlands, and savannahs are being replaced by an unprecedented forest ecosystem. In Mississippi, these new forest systems are dominated in the mid- and understory by mesophytic species such as red maple (Acer rubrum L.) and sweetgum (Liquidambar styraciflua L.). Partial thinning of trees folloby prescribed fire can regenerate oaks in managed timber stands. A severe tornado occurred on a monitored oak stand in northern Mississippi. Of the damaged plots, some were treated with either prescribed fire or salvage logging or were left alone. I examined …

Conservation Genetics And Distribution Of The Yazoo Darter (Etheostoma Raneyi), Kenneth Alan Sterling

Electronic Theses and Dissertations

The Yazoo Darter is a range-restricted endemic fish in north-central Mississippi. Because the limited and fragmented range of this species puts it at risk of extinction, the Yazoo Darter has been classified as vulnerable or sensitive by several agencies and conservation organizations. However, the actual conservation status of this species is uncertain. Information necessary for conservation management is relatively sparse and is scattered among published and unpublished sources, particularly collection records. I have consolidated all known collection records for this species into a standardized database which has not only yielded valuable information presented here, but will provide a resource for …

Nutrition Assessment And Intervention Improves Body Composition And Diet In Ncaa Female Volleyball Players, Rachel Wenzel

Electronic Theses and Dissertations

Intercollegiate volleyball is a powerful sport that consists of two to three hour matches; therefore, optimal physical condition is critical for top performance. This study assessed nutrition and anthropometric parameters at the start and conclusion of both the spring 2009 (no intervention) and spring 2010 (intervention) off-seasons as well as additional measurements four months after the intervention. The subject' body composition, total energy, carbohydrate and protein needs were calculated and intakes were assessed. The intervention consisted of monthly individual nutrition counseling sessions based on analysis of intake from three-day food records. Food records were analyzed using Nutrient Data System for …

Population Biology Of A Coastal Dune-Dwelling Spider (Arctosa Sanctaerosae) Along The Hurricane Disturbed Northern Gulf Of Mexico Coast, Robert A. Hataway

Electronic Theses and Dissertations

With the continued increase in the number of tourists visiting the Northern Gulf coast in the last century and the resulting development of this coastline the habitat of Arctosa sanctaerosae has become fragmented; and the sprawl of large cities along the coast has further degraded available habitat. In addition to anthropogenic disturbance to this coastal region, hurricanes are an additional and natural perturbation to the ecosystem. This habitat has seen a number of major tropical storms over the last decade and I have sought to explore the impact of habitat destruction and storm-induced disturbance on a species of spider endemic …

Relationship Between Coastal Vegetation Biomass With Elevation And Salinity Gradients, Ying Chen

Electronic Theses and Dissertations

Surges and waves generated by hurricanes and other severe storms can cause devastating damage to property and loss of life in coastal areas. Vegetation in wetlands and coastal fringes can reduce storm surges and waves while complementing traditional coastal defense approaches such as permanent levees, seawalls and gates. The effectiveness of marsh vegetation in attenuating storm surge energy and reducing soil erosion depends on the level of primary production at the time of the storm surge and the ability of marsh vegetation to recover rapidly from damage caused by the storm surge. Marsh production depends on a variety of abiotic …

Response Of Riparian Plant Communities To Hydrological Alteration: Are Seed Banks A Means Of Restoration?, Siobhan Boyer Gorham

Electronic Theses and Dissertations

The effects of anthropogenic modifications of stream systems on in situ plant community composition and seed bank composition were examined at five riparian sites in the Yazoo River watershed in northern Mississippi. This analysis was performed to determine if the soil seed bank can provide a means for the restoration of riparian floodplain plant communities. The study sites represented five different kinds of hydrological alteration: a highly incised riparian terrace isolated from the stream channel, a deforested original stream with reduced flow due to channelization and standing water due to levees, a forested original stream with reduced flow due to …

Influence Of Vegetation On Sediment Bacterial Community Structure, Microbial Enzyme Activities And Phosphorus Retention In Constructed Freshwater Wetlands, Rani Menon

Electronic Theses and Dissertations

Agricultural activities are major sources of non-point pollutants causing eutrophication. Constructed wetlands are used as a best management practice for sequestration of nutrients from agricultural runoff. This dissertation focuses on the influence of vegetation on bacterial community structure, microbial enzyme activities, and phosphorus retention capacity of constructed wetland systems. A greenhouse experiment was conducted using unvegetated or vegetated mesocosms with Juncus effusus, Carex lurida or Dichanthelium acuminatum var. acuminatum in monoculture or mixed culture.

To study the influence of vegetation on the bacterial community structure and microbial enzyme activities, sediment samples were taken from monoculture mesocosms in the greenhouse. β-1,4-glucosidase, …

Ectomycorrhizal Fungal Succession In A Native Monterey Pine Forest And Its Potential Influence Upon Forest Population Dynamics, Kristopher Jordan Hennig

Electronic Theses and Dissertations

Ectomycorrhizal fungi are plant symbionts influential to the growth and survival of many plant species found within forest ecosystems throughout the globe. The succession of ectomycorrhizal communities during forest maturation has been observed in a number of systems; however, though it is generally assumed that this process is important for forest dynamics, we do not fully understand the causes of succession and whether it strongly influences metrics of plant population dynamics such as population growth rates or size class structure. I studied a secondary successional chronosequence to test the hypothesis that ectomycorrhizal fungal succession occurs within a native Monterey pine …

Development And Evaluation Of Let's Eat Smart: A Pilot School-Based Nutrition Intervention For Elementry School Children In Kuwait, Sondos Ahmad Kalendar

Electronic Theses and Dissertations

Due to nutrition transition, the prevalence of childhood obesity is increasing significantly worldwide especially in affluent developing countries such as Kuwait. Obesity is associated with adverse chronic health conditions and financial burdens which provides an incentive for prevention. The objective of the study was to examine the effectiveness of a multi-component school-based nutrition intervention designed to improve healthy eating knowledge, attitudes, self efficacy and dietary behaviors among fourth and fifth graders in Kuwait. The Let's Eat Smart program was based on the social cognitive theory and used short interactive lessons, DVD sessions, posters, food models and parental letters to promote …

In Vitro And In Vivo Pharmacodynamic Characterization Of The Novel Plasma Kallikrein Inhibitor Pf-04886847, Dhaval Sanjeev Kolte

Electronic Theses and Dissertations

Plasma kallikrein plays an important role in the pathogenesis of inflammation and thrombosis. Kallikrein cleaves high molecular weight kininogen (HK) to liberate the potent pro-inflammatory peptide bradykinin (BK). BK upon activation of its constitutive B2 receptors on endothelial cells leads to an increase in intracellular Ca2+ level and subsequent production of nitric oxide (NO) and prostacyclin (PGI2), ultimately leading to vasodilation, hypotension, increased vascular permeability and vascular leakage. Further, kallikrein activates the complement system and stimulates neutrophil chemotaxis, aggregation and elastase release. Furthermore, kallikrein mediates the conversion of factor XII (FXII) to activated factor XII (FXIIa) thereby potentiating the intrinsic …

Epigenetic Effects Of Benzo(A)Pyrene In Fundulus Heteroclitus And Danio Rerio, Xiefan Fang

Electronic Theses and Dissertations

DNA methylation is one of the epigenetic mechanisms that controls gene expression and is vulnerable to early life environmental toxicant exposures. Our goal was to use two fish models, Fundulus heteroclitus and Danio rerio (zebrafish), to study the benzo(a)pyrene (BaP) effects on DNA methylation status and whether the alterations could contribute to BaP-mediated reproductive and developmental toxicities. Initially, we used Fundulus to study BaP effects on glycine N-methyltransferase (GNMT) expression throughout development. Fundulus embryos were exposed to waterborne BaP at nominally 10 or 100 μg/L and both GNMT mRNA expression and enzyme activity were measured. Quantitative PCR and whole mount …

A Menu Analysis Of Sorority Meals At The University Of Mississippi, Jessica Lauren Moosa

Electronic Theses and Dissertations

Students transitioning to university life face numerous challenges including the problem of making healthy dietary choices. Sorority members are uniquely suited to examining dietary habits because of their access to regular planned meals and because of the social stresses they experience in regards to body image. Menus are not required to follow nutrient specific guidelines and the nutrient content of sorority meals has not been evaluated at the University of Mississippi. The purpose of this study is to analyze nutrient content of sorority meals and determine if members are able to obtain adequate amounts of nutrients from the foods offered. …