Life Sciences Commons^™

Predator Scent And Presence Alter Mammal Assemblages In The Missouri Ozarks, Usa, Cara Jean Yocom-Russell

Masters Theses

"Species that are vulnerable to predation exhibit a host of behavioral and physiological adaptations toward the avoidance of this outcome: Heightened awareness of surroundings through visual, olfactory, and auditory senses are common ways in which these species avoid detection by predators. While links between direct predator-prey relationships are well established, less is known about how predators can shape overall community structure or the populations of secondary or less frequently consumed prey items. As humans expand into rural areas, the frequency of wildlife conflicts rises. In response, humans look to prevent these events with a variety of methods. One such method …

Aquatic Plants And Their Application To Successful Floating Treatment Wetlands, Katherine May Mazanec

Masters Theses

“This research aims to mitigate eutrophication of freshwater habitats affected by urban stormwater runoff. Two highly impacted urban ponds near the Missouri S&T campus in Rolla were the focus of this research on the application of floating treatment wetlands (FTWs). An FTW consists of a man-made floating mat that is planted with emergent or floating macrophytes. The plants grow on the mat and their roots extend into the water column below the mat. Plant tissues, especially roots in direct contact with the water, take up nutrients, act as biofilm growth sites, and may facilitate precipitation of nutrients. With urbanization, ponds …

Evaluation Of The Symbiotic Relation Between Endophyte And Poplar Trees Exposed To Landfill Leachate, Catalina Vega Hurtado

Masters Theses

“The contamination of soil and groundwater from leachate leakage from landfill has turned, nowadays, into a global public issue. One of the main concerns about this pollutant is the potential threat to human and ecosystem health. The current research studied endophyte bacteria in association with poplar trees (Populus sp.), as a method of bioremediation of landfill leachates. The objective of the project was to identify treatment strategies that may improve plant performance (survival rates, plant fitness, and degradation efficacy) with the purpose of being implemented in phytoremediation plots, aimed to intercept and treat landfill leachate, before the contamination of watershed. …

Characterization Of Chromosomal Translocations In A Group Of Killifish Species By Using Genome-Wide High-Density Snp Mapping Approach, Naznin Sultana Remex

Masters Theses

"The role of chromosomal rearrangements in reproductive isolation and introgression between species is poorly understood. In heterozygous form, rearrangements may directly interrupt meiotic progression leading to partial sterility/subfertility (underdominance) or may suppress local meiotic segregation (recombination suppression). Such unbalanced meiotic segregation may also result in reproductive isolation and play roles as a driving force of speciation. The objective of this study was to gain insight into the pattern of chromosomal rearrangements in two closely related killifish species in the genus Fundulus (F. notatus, and F. olivaceus) by constructing genetic linkage maps using high-resolution single nucleotide polymorphism (SNP) …

Ph Dependent Antibiotic Resistance Of An Alkaliphilic, Halotolerant Bacterium Isolated From Soap Lake, Washington, Tiffany Charlynn Edwards

Masters Theses

"Soap Lake, located in Washington State, is a meromictic, soda lake. Many bacterial isolates retrieved from Soap Lake have been noted to possess resistance to multiple antibiotics. A likely explanation for the wide range of antibacterial resistance exhibited by these strains is due to the impact of high alkalinity on the antibiotics themselves and not due to the presence of antibiotic resistance genes. The aim of our study was to determine if select antibiotics are effective against Halomonas eurialkalitoleranis, a bacterium capable of growth over a wide range of neutral to alkaline pH values, to investigate the influence of alkalinity …

Dephosphorylation Of Iqg1 By Cdc14 Temporally Regulates Actin Ring Formation, Daniel Patrick Miller

Masters Theses

"Cytokinesis is the final step in cell division when the cell separates the cytoplasm by contracting a ring composed of filamentous actin (F-actin) and type II myosin. Iqg1, an IQGAP family member, is an essential scaffolding protein in budding yeast (S. cerevisiae) required for actin recruitment to, and contraction of, the actomyosin ring. Actin is recruited by the calponin homology domain (CHD) in anaphase after Iqg1 is localized to the bud neck. Consensus sites for the cyclin-dependent kinase (CDK) Cdc28 were identified flanking the CHD. This led us to the hypothesis that phosphorylation of Iqg1 by Cdc28 negatively regulates actin …

Characterization Of A Plant Gene Family Expanded In Glycine Max, Lisa Snoderly-Foster

Masters Theses

"Glycine max, commonly named the cultivated soybean, is one of the oldest and most important food crops in the world. The study of the G. max genome provides valuable insight into the molecular mechanisms that govern its reproduction and environmental responsiveness, key factors in maximizing crop yield. Since the complete sequencing of the genome in 2010, the analysis has become faster and easier, especially with the development of numerous web-based, publically accessible bioinformatics tools.

This research effort utilizes these tools to characterize a small, unannotated G. max gene family. Although no definitive evidence was uncovered for the production of a …

Investigation Of Angiogenic Effects Of Bioactive Borate Glass Microfibers And Beads In A Rodent Model, Richard Jeffrey Watters

Masters Theses

"The primary objective of this research project was to evaluate the effects of three different compositions of bioactive glass microfibers (45S5, 13-93B3, and 13-93B3Cu) and bioactive glass beads (13-93, 13-93B3, and 13-93B3Cu) on angiogenesis in subcutaneous tissue in the SKH1 'hairless' mouse. Microvascular responses to the bioactive glass implants were investigated via three experimental approaches: noninvasive vital imaging of microvasculature in dorsal skin windows; quantitative histomorphometry of microvascular densities; and quantitative PCR measurements of mRNA expression of pro-angiogenic cytokines VEGF and FGF-2. The live imaging of dorsal skin window preparations in the hairless SKH1 showed the formation of a halo-like …

Ecology Of A Declining Great Plains Fish, Fundulus Sciadicus, In The Missouri Ozarks, Gregory Travis Thompson

Masters Theses

"Anthropogenic habitat disturbances are of growing concern due to their impacts on native biota, especially in freshwater ecosystems. Damming, channelization, urbanization, wetland draining, and non-native fish introductions all play large roles in habitat homogeneity, fragmentation, and species competition. This has negative effects on native fish and invertebrate species. In the Midwestern United States, the plains topminnow (Fundulus sciadicus) has been declining across its range, to the point of becoming a species of special concern in Missouri. This is possibly due to a combination of the above anthropogenic habitat disturbances. To better understand the ecology of the plains topminnow …

Broad-Spectrum Antibacterial Properties Of Metal-Ion Doped Borate Bioactive Glasses For Clinical Applications, Megan Ottomeyer

Masters Theses

"Bioactive glasses with antimicrobial properties can be implemented as coatings on medical devices and implants, as well as a treatment for tissue repair and prevention of common hospital-acquired infections such as MRSA A borate-containing glass, B3, is also undergoing clinical trials to assess wound-healing properties. The sensitivities of various bacteria to B3, B3-Ag, B3-Ga, and B3-I bioactive glasses were tested. In addition, the mechanism of action for the glasses was studied by spectroscopic enzyme kinetics experiments, Live-Dead staining fluorescence microscopy, and luminescence assays using two gene fusion strains of Escherichia coli.

It was found that gram-positive bacteria were more …

Production Of 1,3-Propanediol From Glycerol Under Haloalkaline Conditions By Halanaerobium Hydrogeniformans, Daniel William Roush

Masters Theses

"With increased demands around the world to make modern lifestyles more environmentally friendly, the chemical commodity market has rapidly shifted. Through new technologies in chemical production, certain high value products have oversaturated the market and have become high-volume, low value waste products. The expansion of biodiesel production offers a prime example; high volumes of glycerol byproduct from this process have shifted glycerol from a high priced commodity to a common waste product. A number of microorganisms are known to synthesize the polymeric precursor 1,3-propanediol from glycerol; however, crude glycerol from biodiesel production creates a harsh environment for most microbes, and …

Wetting And Drying Cycles And The Fungal Communities On Leaf Litter In Streams, Kele Qwinn Thrailkill

Masters Theses

"Leaf litter is a major source of energy for streams in deciduous forests. Fungi play a critical role by converting the leaves into nutritional material for the rest of the food web. The breakdown of leaf litter and associated biota, including invertebrates and fungi, have been proposed as measures of stream health in systems affected by anthropogenic activity. Rates of leaf breakdown can be depressed in streams affected by acidity, metals, organic contaminants, and other stressors. Climate change may lead to alterations in stream hydrology such that streams experience more frequent floods as well as drying episodes. Fungal communities can …

Physiochemical Characteristics Contributing To The Cytotoxicity Of Transition Metal Oxides, Chi-Heng Wu

Masters Theses

"In the past ten years nanotechnology has not only evolved to play a prominent role in our economy but also increased the concern over potential adverse effects caused by nanomaterials to human health and the environment. Nanotoxicity is to understand the nature and origin of the toxicity imposed by nanomaterials. Studies from our laboratory have shown that nanoparticle induces oxidative stress, perturbs calcium homeostasis, alter gene expression, and produces pro-inflammatory responses. We also identified a trend of toxicity: TiO₂ < Cr₂O₃ < Fe₂O₃ < Mn₂O₃ < NiO < ZnO < CuO. We then asked a question: what are physiochemical factors of transition metal nanoparticles that contributed to this increasing cytotoxicity. In this thesis I investigated the correlation between physicochemical properties and toxicity of the transition metal oxides in the 4th Period of the Periodic Table of Elements. Particle size, BET surface area, point of zero charge, metal dissolution, and degree of surface adsorption of transition metal oxide nanoparticles were measured. There were no increasing trends in both particle size and specific surface area. The point of zero charge showed an increasing trend as TiO₂ < Cr₂O₃ < Fe₂O₃ < NiO < CuO = ZnO < Mn₂O₃. The number of available binding sites of nanoparticle showed an increasing trend as Cr₂O₃ > ZnO > CuO > NiO > Fe₂O₃ > Mn₂O₃ > TiO₂. The degree of adsorption on the surface of nanoparticles showed an increasing trend with atomic …

Analysis Of A Wound-Induced Gene Family In Glycine Max, Gena Robertson

Masters Theses

Gene families in plants are important in understanding genome evolution indicating when and where genome duplications and segmental duplications occurred as well as subsequent divergence and subfunctionalization. A gene family in Glycine max that encodes a WI12 protein, wound-induced protein, was found to consist of ten genes on five chromosomes. Wound-induced proteins are activated in response to wounding in plants, and the WI12 protein in particular is thought to be involved in cell wall modifications at the wound site. A variety of bioinformatics tools have been used to analyze the expansion of this family in soybean as well as identify …

Mutation Of The Hof1 Pest Domain Affects Cytokinesis In Budding Yeast, Katherine E. Stockstill

Masters Theses

"Cytokinesis is the division of a cell into two daughter cells. Cytokinesis failure results in polyploidy, which may contribute to tumorigenesis or cause cell death. The Saccharomyces cerevisiae protein Hof1, which is required for efficient cytokinesis, is phosphorylated during mitosis. The hypothesis that MEN (mitotic exit network) dependent phosphorylation regulates Hof1 degradation, triggering completion of cytokinesis was tested. Hof1 contains a PEST sequence, which is rich in proline, glutamic acid, serine, and threonine, and is believed to be involved in protein degradation. To test the hypothesis, we created two non-phosphorylatable mutants of the Hof1 PEST domain tagged with GFP. The …

Isolation And Characterization Of Bacterial Symbionts From Crotalaria Spectabilis Grown On Trichloroethene Contaminated Soil, April Lyn Rocha

Masters Theses

"The discovery of several members of the Leguminosae family growing on a TCE contaminated site demonstrated that they have the capabilities to tolerate the TCE contamination. This led to an investigation of the plants' ability to metabolize TCE. Research by Dr. Lee Newman showed that nodules from Crotalaria spectabilis grown on the site had TCE metabolites present while nodules from other legumes at the site did not. The presence of TCE metabolites within the C. spectabilis nodules suggests that the bacterial symbiont may be responsible for TCE metabolism. This led us to investigate the symbiont of C. spectabilis and its …

Synthesis And Toxicity Studies Of Imidazolium-Based Ionic Liquids, Ninu Madria

Masters Theses

"There is a considerable recent interest in the applications of room temperature ionic liquids (RTILs) as green solvents in organic synthesis and as nonvolatile electrolytes in lithium ion batteries. A variety of commercially available imidazolium based RTILs have been used for these applications, mainly due to their negligible vapor pressures, high thermal stabilities, wide liquid range, wide electrochemical windows and high anodic stability. The state of the art lithium ion batteries require the use of electrolytes that have relatively low viscosities at temperatures as low as -35°C. This thesis describes the synthesis of novel oxygenated and fluorinated imidazolium based RTILs …

Analysis Of Eurycea Hybrid Zone In Eastern Missouri, Bonnie Jean Beasley

Masters Theses

"Evolutionary mechanisms are often difficult to observe in action because evolution generally works slowly over time. Hybrid zones provide a unique opportunity to observe many evolutionary processes, such as reinforcement, because of the rapid changes that tend to occur in these zones. Salamanders provide an ideal model for examining the rapid changes in populations that result from hybridization because many closely-related species lack reproductive barriers. In Missouri, a well-documented hybridization zone exists among the two subspecies Eurycea longicauda longicauda (long-tailed salamander) and E. L. melanopleura (dark-sided salamander). These salamanders inhabit caves, limestone creek beds, and abandoned mine shafts. A closely …

The Role Of Skeletal Development In Body Size Evolution Of Two North American Frogs, Sarah Beth Havens

Masters Theses

"In order to better understand the evolution of miniaturization in Acris blanchardi, a North American Hylid with a unique life history and of ecological interest in the United States. The development and ossification sequences of 48 larvae, 5 juveniles and 5 adult A. blanchardi were examined. The adult was described by Maglia et al. (2007) to be a miniature and to display morphological novelties. In addition, 44 larvae, 2 juvenile and 5 adults of Pseudacris crucifer a closely related frog that has been suggested to be a miniature, were examined. The cranial and postcranial adult elements of this species, as …

Zinc Oxide Nanoparticle Disruption Of Store-Operated Calcium Entry In A Muscarinic Receptor Signaling Pathway, Hsiu-Jen Wang

Masters Theses

"The influences of ZnO nanoparticles on cellular responses to activation of muscarinic receptors were studied in Chinese hamster ovary cells expressing the human M3 muscarinic acetylcholine receptor. ZnO particles (20 nm) induced cytotoxicity in a time and concentration-dependent manner: following a 24 h exposure, toxicity was minimal at concentrations below 20 µg/ml but virtually complete at concentrations above 28 µg/ml. ZnO particles did not affect antagonist binding to M3 receptors or allosteric ligand effects, but increased agonist binding affinity while eliminating guanine nucleotide sensitivity. At a noncytotoxic concentration (10 µg/ml), ZnO increased resting [Ca²⁺]i from 40 to 130 nM without …

Laryngeal Apparatus And Call Structure In North American Hylids, Barbara Ann Catherine Fears

Masters Theses

"Although the ecological implications and structure of frog calls have been the subject of much study, little is known about the association between the laryngeal apparatus morphology and call structure in North American hylids. In this study linear measurements of the laryngeal apparatus were captured and compared to the call structures of thirteen species of North American hylids. Species examined included: Pseudacris crucifer, P. triseriata, P. ocularis, Acris crepitans blanchardi, Hyla avivoca, H. cinerea, H. gratiosa, H. chrysoscelis, H. versicolor, H. squirella, H. femoralis, H. arenicolor, and H. eximia. Six homologous landmark points were identified, and the lengths between them …

Nona-Arginine Peptides Facilitate Cellular Entry Of Semiconductor Nanocrystals: Mechanisms Of Uptake, Yi Xu

Masters Theses

"Luminescent semiconductor quantum dots (QDs) have recently been used for delivering and monitoring biomolecules, such as drugs and proteins. However, QDs alone have a very low efficiency of transport across the plasma membrane. In order to increase the efficiency of QD delivery, synthetic nona-arginine (sR9) was used, a cell penetrating peptide, to facilitate uptake. Data demonstrated that sR9 could significantly increase the cellular uptake of QDs by noncovalent binding between QDs and sR9. Furthermore, the mechanisms of QD/sR9 cellular internalization were investigated. Low temperature and metabolic inhibitors markedly inhibited the uptake of QD/sR9, indicating that internalization is an energy-dependent process. …

Electricity Generation And Ethanol Production Using Iron-Reducing, Haloalkaliphilic Bacteria, Varun Paul

Masters Theses

"Microbial life in extreme environments has been studied primarily for their metabolic activities. Very few commercial or industrial applications have been known from these systems. In this study, the metabolic pathways and properties of bacteria from a haloalkaliphilic environment of Soap Lake, Washington were employed in two research applications related to energy production. In the first study, the bacterial cultures that were known to reduce iron (III) were used in a Microbial Fuel Cell (MFC) reactor. Iron reducing bacteria have shown to shunt their electrons on to the surface of a carbon electrode of an MFC, and the electrons can …

In Vitro Evaluation Of Bioactive Glass Scaffolds And Modified Bioactive Glasses With An Osteogenic Cell Line, Vernon C. Modglin

Masters Theses

"This investigation consisted of two parts focused on bioactive glasses and scaffolds for in vitro growth of bone cells for tissue engineering and bone repair. The first part involved evaluation of the ability of two new types of porous 13-93 bioactive glass scaffolds to support the growth and differentiation of mouse MLO-AS cells, an established osteogenic cell line used as a model of developing bone tissue. The two scaffold types tested included 13-93 glass fiber and trabecular-like scaffolds seeded with MLO-AS cells and cultured for intervals of 2 to 12 days. Collectively, in vitro results indicate that the 13-93 glass …

Oxidative Stress, Calcium Homeostasis, And Altered Gene Expression In Human Lung Epithelial Cells Exposed To Zno Nanoparticles, Chuan-Chin Huang

Masters Theses

"The influence of 20 nm ZnO nanoparticles on oxidative stress, intracellular calcium homeostasis, and gene expression was studied in human bronchial epithelial cells (BEAS-2B). ZnO caused a concentration- and time-dependent cytotoxicity while elevating oxidative stress and causing membrane damage (cellular LDH release). There was a remarkably steep relationship between concentration and toxicity at concentrations from 5 to 10 μg/ml. Exposure to ZnO increased intracellular calcium levels in a concentration- and time-dependent manner. Treatment with the antioxidant N-acetylcysteine prevented cell loss and diminished the increase in intracellular calcium concentration, suggesting oxidative stress mediated cytotoxicity. Exposure to a sublethal concentration of ZnO …

The Identification And Characterization Of Phenylalanine Ammonia-Lyase Gene Family Members In Glycine Max, Erin Kathleen Pringle

Masters Theses

"Gene families are collections of genes with similar functions. Studying gene families is important for understanding the evolution of genes and manipulating genes. Phenylalanine ammonia-lyase (PAL) is an enzyme found in plants. It catalyzes the deamination of phenylalanine to produce cinnamic acid. Genes for PAL have been identified in many different plant species. This project used the known sequence for the PAL1 gene in Glycine max to find other PAL genes in Glycine max"--Abstract, page iii.

Role Of Microtubules In Budding Yeast Cytokinesis, Su Young Park

Masters Theses

"Cytokinesis is an important step to finish cell cycle events and separate into two daughter cells. This event is driven by actomyosin ring contraction. In budding yeast, the mitotic exit network (MEN) controls completion of ana/telophase by signaling events. Bub2 is a mitotic exit network regulator and binds to Tem1p which is an important component in MEN. Mad2 is a component of a separate spindle checkpoint. Mad2 dependent pathway prevents the metaphase to anaphase transition under spindle damage. Because yeast cells have cell walls, septum formation follows actin ring contraction. Here it was investigated how microtubule defects affect cytokinesis in …

Screening New Cytokinesis Genes And Investigation Of Regulation Of Hof1 In Cytokinesis, Jung Eun Park

Masters Theses

"In 1996, a complete sequence of the budding yeast genome was completed and numerous studies begun to discover the function of genes. A primary concern of this study was to identify genes that may function in cytokinesis. Seven candidate genes were chosen, which were previously shown to localize to the bud neck, the site of cytokinesis, or interact with a protein that is involved in cytokinesis. Six of those uncharacterized genes, YHR149C, YLR187W, YOL070C, YMR124W, YPL158C, and YOR304C-A, were identified by data generated by GFP tagging of the yeast proteome. Data from a large-scale two-hybrid screen was used to identify …

Antimicrobial Activities Of Aldehydes And Ketones Produced During Rapid Volatilization Of Biogenic Oils, Aruna Lamba

Masters Theses

"The overall objective of the research presented in this thesis was to evaluate the antimicrobial properties of commercially available neat compounds in order to validate the analytes which were found in the smoke generated during rapid volatilization of biogenic oil esters and mineral oils. To attain this objective various analytes were selected from the analytical data provided for the smoke, and neat compounds were purchased. A special desiccator was designed to conduct experiments. Simultaneously vapor phase concentration of the neat compounds was determined to establish relation between neat compounds and the analytes found in smoke. Other part of the thesis …