Biology Commons^™

The Tettigoniidae (Orthoptera: Ensifera): Phylogeny, Origins, And Leaf-Like Crypsis, Joseph D. Mugleston

Theses and Dissertations

Tettigoniidae (katydids) has more than 7200 species and is the largest family within the insect order Orthoptera. Their unique biology including leaf-like crypsis, acoustic signaling, and courtship rituals garners much of their academic attention. However, the taxonomy of katydids is chaotic and previous to these studies, little work had been done to decipher the phylogenetic relationships within this family. Without a robust phylogenetic framework, questions regarding the evolution of katydid disguises including the leaf-like crypsis cannot be addressed. This dissertation contains three chapters. Chapter 1 provides the first phylogenetic hypothesis focusing on Tettigoniidae. In this chapter we show a character …

Molecular Studies Of South American Teiid Lizards (Teiidae: Squamata) From Deep Time To Shallow Divergences, Derek B. Tucker

Theses and Dissertations

I focus on phylogenetic relationships of teiid lizards beginning with generic and species relationship within the family, followed by a detailed biogeographical examination of the Caribbean genus Pholidoscelis, and end by studying species boundaries and phylogeographic patterns of the widespread Giant Ameiva Ameiva ameiva. Genomic data (488,656 bp of aligned nuclear DNA) recovered a well-supported phylogeny for Teiidae, showing monophyly for 18 genera including those recently described using morphology and smaller molecular datasets. All three methods of phylogenetic estimation (two species tree, one concatenation) recovered identical topologies except for some relationships within the subfamily Tupinambinae (i.e. position of …

Estrogen's Effects On Oxidative Stress Levels In Glial Cells, Jacob J. Dirkman

Theses and Dissertations

A decrease in astrocyte function and viability has been linked to many neurodegenerative diseases, including schizophrenia, major depressive disorders, Alzheimer’s disease, and Amyotrophic Lateral Sclerosis (ALS). Previous research indicates that some estrogens may have a positive effect on neuron and astrocyte viability. Estrogens’ effects on the brain are of interest as estrogens are commonly prescribed as hormone replacement therapy to reduce the symptoms of menopause in women. Unfortunately, these effects on are not completely understood. The goal of the project was to discover if estrogen has any protective effect on astrocytes exposed to oxidative stress. We measured the oxidative stress …

Relationships Between Texas Tortoise Carapace Length, Home Range Size, And Habitat Selection At Sites With Invasive Grass, Kiley V. Briggs

Theses and Dissertations

Invasive grasses in south Texas have the potential to negatively impact the threatened Texas tortoise (Gopherus berlandieri) by reducing the availability of preferred foods (forbs) and may cause tortoises to travel farther, lead to reduced carapace length, and reduce the availability of refugia from heat stress. I used compositional analysis, regression, and ANOVA to explore relationships between invasive grasses and habitat use, home range size, and carapace length, as well as compared daily maximum temperatures between tussocks of an invasive and native grass. Forbs were ranked higher in use over invasive grasses in compositional analysis, but not strongly so (p …

Apoptotic And Necrotizing Mechanisms Of Recombinant Panton-Valentine Leukocidin In Thp1 Monocytes., Heriberto Deleon Iii

Theses and Dissertations

The Panton-Valentine Leukocidin (PVL) is a highly specialized bacterial exotoxin produced by Staphylococcus aureus. The increased degree of invasiveness of community associated methicillin resistant Staphylococcus aureus (CAMRSA) has been attributed to the relatively high rates of PVL produced by the pathogen, thus increasing pathogenicity and virulence. The increased rates of PVL encoding CAMRSA infections have been correlated with increased rates of necrotizing fasciitis, invasive osteomyelitis and invasive necrotizing pneumococcal infections. Previous research as revealed that PVL has the ability to induce apoptosis at low concentration (5nM-10nM) and necrosis (50-100nM) at high concentrations, with little detail on the mechanism of initiation. …

Jatropha Curcas Protoplast Isolation And Inhibitory Effects Of Culture, Christopher S. Lukaszewski

Theses and Dissertations

Improvement on the sub-tropical plant Jatropha curcas may increase the use of this drought tolerant oilseed crop for the production of biodiesel. One of the methods for enhancing a species is through genetic manipulation of the protoplast. Isolating protoplasts is challenging and culturing has many obstacles similar to those seen in tissue culture, such as oxidative browning. Successful isolation of J. curcas leaf protoplasts resulted in an average of 3.23 x 106 viable protoplasts/mL. However, protoplasts diminished within 2 days after culturing. A review of the potential solutions used for overcoming the inhibitory effects of culture may reveal further insight …

Characterizing Benthic Invertebrate Communities At Five South Texas Banks, Maria T. Cooksey

Theses and Dissertations

On the continental shelf off the coast of South Texas lie a series of hardbottom structures known as the South Texas Banks, which provide critical habitat for benthic organisms and pelagic fish species. The depth of the banks, a persistent nepheloid layer, and strong currents have hindered efforts to collect quantitative data on what inhabits the rocky outcrops and relic coral-algal reefs. Using a remotely operated vehicle, video data from five of the banks were collected in order to characterize the benthic communities. Southern and North Hospital Banks were found to be the most diverse of the studied South Texas …

Why Are Students Doing Research? Examining The Motivation Of Students Involved In Undergraduate Research Programs, Andrew Layne Mcdevitt

Theses and Dissertations

Use of self-determination theory (SDT) within the science classroom focuses primarily on ways to integrate intrinsic motivation into students' identity. Experiential learning plays a large role in promoting learning by shaping students' interests, identity, and intrinsic aspirations. This phenomenological research study sought to understand how experiential learning experiences helped influence career aspirations of graduate students within ecological disciplines. By determining how their experiences met three basic psychological needs outlined by SDT (competence, autonomy, and relatedness), we were able to examine which regulators drove motivation.

In the qualitative pilot study, participants developed a genuine enjoyment and appreciation for their discipline as …

An Investigation Into B Cells In Peripheral Blood And Gut Associated Lymphoid Tissues In The Red Eared Slider Turtle, Trachemys Scripta, Sarah Marie Marrochello

Theses and Dissertations

As in endotherms, immunity in ectotherms is vital to survival and contributes to the overall fitness of an organism. For reptilians, there are a number of environmental factors, such as temperature, season, and pathogen prevalence, which are known to influence both innate and adaptive immunity. Of particular interest, is the effect of these factors on B cells, a component of adaptive immunity. Reptilian B cells are reported to secrete antibodies, much like their mammalian counterparts, and undergo phagocytosis. The work reported here primarily focused on understanding the effect of environmental temperature, incubation temperature, and nesting season on B cells in …

Î?- Lactam-Induced Changes In Cell Wall Composition And Autolytic Properties Of Daptomycin Resistant Staphylococcus Aureus, Michael Krzyskowski

Theses and Dissertations

Staphylococcus aureus is a major human pathogen that is well known for its ability to develop resistance to antimicrobial therapies. Recent studies have identified a combination of β-lactam antibiotic and daptomycin (DAP) to be highly effective at killing single and multi-drug-resistant S. aureus. Of particular interest is this drug combinationâ??s efficiency with which it kills strains classified as DAP-resistant methicillin-resistant Staphylococcus aureus (DAP-R MRSA). The goals of the present study were two-fold: to provide a physiological profile of a DAP-R S. aureus strain undergoing beta-lactam treatment by observing changes in autolytic rate, susceptibility to lytic enzymes, levels of peptidoglycan O-acetylation, …

Phylogenetic Relationships Of Cottids (Pisces: Cottidae) In Upper Snake River Basin Of Western North America, Sun Yeong Oh

Theses and Dissertations

Freshwater sculpins (Cottus) are common throughout temperate regions of the Northern Hemisphere. Their broad distribution in the Western North America makes them a good model for understanding phylogeographic relationships among western fishes. Within much of the interior west three lineages, C. bairdii, C. confusus, and the C. beldingii complex, are most prevalent. The distribution of these three overlap in the Snake River Basin. All occur below Shoshone Falls on the Snake River. However, only two currently reside in the Upper Snake River above the falls. An exception are the Lost River streams of central Idaho. While …

Accepting Evolution And Believing In God: How Religious Persons Perceive The Theory Of Evolution, Katherine F. Manwaring

Theses and Dissertations

Students frequently hold an incorrect view of evolution. There are several potential barriers that prevent students from engaging evolutionary theory including lack of knowledge, limited scientific reasoning ability, and religiosity. Our research provides tools for overcoming barriers related to religiosity and diagnoses the barriers preventing students from fully engaging in learning the theory of evolution. This was a two-part study. The first part of our study addressed two hypothesized barriers to learning evolutionary theory among members of The Church of Jesus Christ of Latter-day Saints (LDS or Mormon): (1) religious views stemming from incorrect understanding of the Church's neutral stance …

The Role Of Nuclear Factor-Erythroid-2-Related Factor 2 In Sensitivity To Thymidylate Synthase Inhibitors In Colon Cancer Cells, Sarah Ashley Clinton

Theses and Dissertations

Nuclear factor-erythroid-2-related factor 2 (NRF2), a member of the cap ‘n’ collar family of bZIP transcription factors, confers protection against oxidative and electrophilic stress. NRF2 is of great interest in cancer research, due to its role in response to chemotherapy. The class of drugs targeting thymidylate synthase (TYMS) has been useful in the treatment of colorectal cancer, among other cancers. It has long been known that inhibition of TYMS leads to depletion of thymidine levels and the onset of programmed cell death, deriving from the enzyme’s function as the sole de novo source of thymidine for DNA replication and repair. …

Screening For Pathogenic Escherichia Coli In The Chattahoochee River, Columbus, Georgia, Micah A. Staples

Theses and Dissertations

Escherichia coli testing is frequently used to indicate the possible presence of harmful pathogens, but E. coli itself can be pathogenic. Serotype 0157:H7, enterohemorrhagic E. coli, is likely the most medically important pathogenic strain of E. coli in the United States. In this study, we surveyed for 0157:H7 and three strains of another pathogenic subtype: enterotoxigenic E. coli. We isolated E. coli colonies from samples taken from the Chattahoochee River in Columbus, Georgia at two different locations, above and below wastewater outputs. We used PCR to test for the individual subtypes and then used a nested PCR protocol …

The Loss Of Methanol Utilization In Methylobacteria, Justin T. Skariah

Theses and Dissertations

Methylobacteria primary uses Cl substrates as a carbon and energy source. This experiment was performed to see if Methylobacteria would lose the ability to use Cl compound methanol after prolonged exposure to multi-carbon substrates. To determine this, the bacteria was grown on MR2A3 (multi-carbon substrates) and MOM (single-carbon substrates) for multiple generations and tested for loss of function on a series of generations. These tests include streaking plates of MOM and R2A with bacteria from MR2A3 then getting a bacterial colony count and also toothpick transfers of the colonies to verify findings. After 20 generations there were no significant decrease …

The Effects Of Musical Intervals From Consonant To Dissonant On The Neural Activity Of Earthworms, Charley L. Weaver

Theses and Dissertations

Music is generated through vibrations of a medium creating what is perceived as tone. Two frequencies played simultaneously create intervals, and those ratios of frequencies determine what is consonant and dissonant. Studies have shown a greater neural response in human participants to consonant intervals (Bidelman and Heinz 2011, Bidelman and Krishnan 2009). In this study, the ventral nerve cord of Lumbricus terrestris was exposed to six dichotic intervals in the form of vibrations through a bass actuator. Nerve activity was recorded for amplitude (mV), duration (ms), and maximum depolarization (mV) of the action potential. There was no significant difference in …

Phylogenetic Analyses Of Andean And Amazonian Tree Communities In Ecuador, Samantha J. Worthy

Theses and Dissertations

The forests of Ecuador are known for their high levels of diversity and endemism, classifying the country as a biodiversity hotspot. Both the western Amazon and Andean montane forests are richly populated with tropical tree species that have been little studied in a community phylogenetic context. The implementation of elevational transects and trait based analyses having proven useful in gaining a better understanding of how environmental factors are affecting the tree community structure in these habitats. The goal of this research was to evaluate the magnitude ofDNA barcode diversity among Amazonian and Andean tree species. Specifically, the objectives were to …

Impact Of A Diesel Spill On Macroinvertebrate Communities In Ponds In S.E. Alabama, Usa, Katie E. Winkles

Theses and Dissertations

In this study, macroinvertebrate communities were examined to determine an indication of the water quality in ponds on a wetlands property after a diesel spill. In 2012, a train derailed, and at least 3000 gallons of diesel fuel leached into a small pond of the wetlands. Even after clean-up attempts there remains major concerns that the contamination spread throughout the wetlands. This concern led to the present study. Macroinvertebrates were the chosen focus due to their sensitivity to changes in the environment. Two field trials were conducted in which Hester-Dendy multiplate samplers were placed in ponds to allow macroinvertebrates to …

The Involvement Of Estrogen Receptors In Astrocyte Survival, Lauren M. Johnson

Theses and Dissertations

Estrogens are a class of hormones that are demonstrated to be neuroprotective. The levels of estrogen in the body decline during menopause which can cause a variety of symptoms. Hormone replacement therapy (HRT) is a treatment option for menopause, however, it has been demonstrated to have adverse side effects. Of the treatment options for adverse side effects of HRT, Selective estrogen Down-regulators do not appear to have an agonist effects on estrogen receptors while Selective estrogen receptor Modulators do. The aim of this study was to determine the role that estrogen receptors play in the survival of astrocytes when placed …

Depth And Development Of The Sonic System In Deep-Sea Macrourid Fishes On The Continental Slope, Jonothan Wrenn

Theses and Dissertations

Work on sound production of deep-sea fishes has been limited to anatomy, and no sounds from identified species have been recorded on the continental slope. Here I examined the sonic muscles of six species in the family Macrouridae by depth (Coelorhincus carminatus, Nezumia bairdii, Coryphaenoides rupestris, Nezumia equalis, Coryphaenoides armatus, Coryphaenoides carapinus,). Due to increasingly limited food with depth, I hypothesized that sonic muscle development would decrease with depth. Sonic muscles were intrinsic and occurred in males and females. Swimbladder and sonic muscle dimensions increased linearly with fish size, but there were no clear differences with depth suggesting …

Seasonal Variation Of Fish And Macroinvertebrate Biomass Spectra In Southern West Virginia Streams, Andrew J. Kirk

Theses and Dissertations

The biomass size spectrum - the power-law scaling relationship between average individual size and total biomass - has often been studied in lake and marine ecosystems, but rarely in lotic systems. The objective of this study was to test for characteristic biomass spectra in small temperate streams. Seasonal fish and macroinvertebrate data, including population abundance and biomass estimates, were collected in three wadeable, southern West Virginia streams from October 2013 to May 2015. Fish abundances were estimated with 3-pass electrofishing (depletion) surveys and individuals were weighed in the field. Macroinvertebrates were collected with a Hess sampler and returned to the …

Roles Of Planar Cell Polarity Proteins In Copa Axon Pathfinding, Ashley Morgan Purdy

Theses and Dissertations

In zebrafish, CoPA (Commissural Primary Ascending) is the first among ascending commissural axons to pathfind anteriorly and form the spinal commissure. One pathway that guides their anterior growth is the planar cell polarity (PCP) signaling pathway, but it is not fully known how PCP signaling regulates anterior guidance. We examined CoPA pathfinding in various PCP mutants to determine if anterior-posterior (A-P) guidance of CoPAs is dependent on PCP signaling. We found that certain PCP mutants exhibited anterior pathfinding defects, with approximately half of all affected CoPAs migrating incorrectly posteriorly. By using a translation-blocking DCC (Deleted in …

Evaluation Of Redox Potential As A Novel Biomarker Of Oxidative Stress, Inflammatory Response, And Shock Using Nanoporous Gold Electrodes, Matthew C. Ellenberg

Theses and Dissertations

EVALUATION OF REDOX POTENTIAL AS A NOVEL BIOMARKER OF OXIDATIVE STRESS, INFLAMMATORY RESPONSE, AND SHOCK USING NANOPOROUS GOLD ELECTRODES

Background: Redox potential is a chemical species’ affinity for electrons. Increased oxidant concentration is associated with disease1,2, yet there is not a way to measure systemic redox status.3 Redox potentiometry uses metal electrodes that do not work in blood because protein molecules adhere on the metal surface, blocking electron exchange.

Methods: Nanoporous gold electrodes have large surface areas that allowed electron exchange to continue in blood.4 Redox potential was measured in blood with ascorbic acid, in cardiac bypass patients and pigs …

Plant Functional Trait And Hyperspectral Reflectance Responses To Comp B Exposure: Efficacy Of Plants As Landmine Detectors, Paul V. Manley Ii

Theses and Dissertations

At least 110 million landmines have been planted since the 1970s in about 70 nations, many of which remain in place today. Some risk of detection may be mitigated using currently available remote sensing techniques when vegetation is present. My study focused on using plants as phytosensors to detect buried explosives. I exposed three species representing different functional types (Cyperus esculentus (sedge), Ulmus alata (tree), Vitis labrusca (vine)) to 500 mg kg^-1 of Composition B (Comp B; 60/40 mixture of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT)), a commonly used explosive mixture, and measured functional traits and reflectance over …

The Effect Of Depth On Development And Sexual Dimorphism Of The Sonic System In Deep Sea Neobythitine Fishes: The Upper Continental Slope, Heba Ali

Theses and Dissertations

Abstract

Background: Cusk-eels from the subfamily Neobythiitinae are one of the major groups of sound-producing fishes on the continental slope. Sounds have never been recorded from a member of this subfamily, and sonic anatomy is considered a proxy for sound production. As the first part of a study on the effects of depth on sonic anatomy, we examined three relatively shallow species from the upper continental slope.

Methods: Three species (Hoplobrotula armata, Neobythites longipes and Neobythites unimaculatus) were examined for sonic anatomy (skeleton, swimbladder and sonic muscles), and sonic and epaxial muscle fibers were measured for diameter. …

Evaluating The Evolutionary And Genetic Relationships Of The Andean Orchids Of Northwestern Ecuador, Kylie Bucalo

Theses and Dissertations

DNA barcoding is a molecular based technique used to separate and identify individual species. Here we establish a DNA Barcode library for the orchid flora of an Andean cloud forest in Northwestern Ecuador. The library contains 135 matK and 136 rbcL DNA Barcodes representing over 33 Orchidaceae genera. Sequence analysis shows percent species resolution was higher for matK (98.8%) than rbcL (70.24%), with a large portion of the unresolved species for the rbcL loci coming from taxonomically complex genera in the subtribe Pleurothallidinae. Neighbor Joining (NJ) trees revealed that the orchid flora of Siempre Verde is divided taxonomically into …

Response Of Soil Microbial Communities To Saltwater Intrusion In Tidal Freshwater Wetlands, Chansotheary Dang

Theses and Dissertations

Saltwater intrusion due to global change is expected to have a detrimental effect on the biogeochemistry of tidal freshwater wetlands. Of particular concern is that fact that salinization can alter the role of these ecosystems in the global carbon cycling by causing shifts in microbial metabolism that alter greenhouse gas emissions and increase carbon mineralization rates. However, our understanding of how wetland microbial community dynamics will respond to saltwater intrusion is limited. To address this knowledge gap and increase our understanding of how microbial communities in tidal freshwater wetlands change over time (1, 3, 12, and 49 weeks) under elevated …

Stains Induce Apoptosis And Autophagy In Primary And Transformed Mast Cells, Patrick A. Paez

Theses and Dissertations

Statin drugs are widely employed in the clinic to reduce serum low density lipoproteins (LDLs) in patients with hypocholesteremia. In addition to their cholesterol-lowering effects through HMG CoA reductase antagonism, isoprenyl lipids necessary for membrane anchorage and signaling of small G-proteins are abrogated. We previously found that statins suppress mast cell activation in murine and human cells, suggesting these drugs might be useful in treating allergic disease. While mast cell function is critical to allergic inflammation, mast cell hyperplasia and survival also impact these diseases, and were not studied in our previous work. In this study, we describe Fluvastatin-mediated apoptosis …

Independent Origination Of Floral Zygomorphy, A Predicted Adaptive Response To Pollinators: Developmental And Genetic Mechanisms, Ghadeer Bukhari, Wenheng Zhang

Theses and Dissertations

Observations of floral development indicate that floral organ initiation in pentapetalous flowers more commonly results in a medially positioned abaxial petal (MAB) than in a medially positioned adaxial petal (MAD), where the medial plane is defined by the stem and the bract during early floral development. It was proposed that the dominant MAB petal initiation might impose a developmental constraint that leads to the evolution of limited patterns of floral zygomorphy in Asteridae, a family in which the floral zygomorphy develops along the medial plane and results in a central ventral (CV) petal in mature flowers. Here, I investigate whether …

Functional Significance Of Mtdna Cytosine Modification Tested By Genome Editing, Jason M. Robinson

Theses and Dissertations

The field of epigenetics is gaining popularity and speed, due in part to its capability to answer lingering questions about the root cause of certain diseases. Epigenetics plays a crucial role in regulation of the cell and cell survival, particularly by cytosine methylation. It remains controversial if DNMT’s which facilitate methylation are present in mammalian mitochondria and what the functional significance they may have on modification of mitochondrial DNA. CRISPR-Cas9 technology enabled genome editing to remove the MTS (mitochondrial targeting sequence) from DNMT1 of HCT116 cells, purposefully minimizing effects on nuclear cytosine methylation, while exclusively impacting mitochondrial modification. Removal of …