Life Sciences Commons^™

Oyster Reef Connectivity Inferred Via Population Genetic Analysis, Brendan Douglas Turley

Dissertations, Theses, and Masters Projects

A panel of 48 single nucleotide polymorphism markers (SNPs) was developed for use in a population genetic analysis of the Eastern Oyster Crassostrea virginica sampled from the lower Chesapeake Bay. The SNPs were developed from published and unpublished sequencing data and developed to be used on a Fluidigm Biomark. A selection of 95 SNPs were chosen initially for development and the best 48 were selected for downstream applications. This project was a collaboration with the non-profit Chesapeake Bay Foundation (CBF) to examine their oyster reef restoration project in the Lafayette River, Virginia. The CBF wanted to test a hydrodynamic connectivity …

Neurotransmitter Systems And Age Related Cognitive Decline: A Focus On Attention And Plasticity, Christine Teal Kozikowski

Dissertations, Theses, and Masters Projects

No abstract provided.

Effect Of Noise On The Social Structure Of European Starlings (Sturnus Vulgaris), Autumn Swan

Dissertations, Theses, and Masters Projects

No abstract provided.

The Reproductive Biology Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, Carissa L. Gervasi

Dissertations, Theses, and Masters Projects

The Striped Bass (Morone saxatilis) is an anadromous finfish that supports a lucrative fishery along the Atlantic coast of the United States and serves as a vital component of estuarine food webs. Once Striped Bass stocks were restored after crashing in the late 1980s, abundance skyrocketed to record levels. Over the past decade however, abundance has steadily declined, concurrent with an outbreak of mycobacteriosis. Disease prevalence is currently >50%, and previous research has demonstrated diseasepositive fish exhibit slower growth and increased natural mortality compared to diseasenegative fish. The purpose of this research was to provide a contemporary description of Chesapeake …

Linking Structure And Function Of Microbial Communities Responsible For Sedimentary Nitrogen Processes In North Carolina Estuaries, Jessica A. Lisa

Dissertations, Theses, and Masters Projects

Estuaries and coastal areas are highly diverse and productive ecosystems that serve as critical habitats for many marine organisms. Anthropogenic activities and changes in coastal land use have resulted in nutrient over-enrichment, posing a threat to the ecological integrity of estuaries. Nitrogen is often the limiting nutrient and its dynamics are central in determining coastal ecosystem health. The cycling and removal of nitrogen is primarily microbially mediated and the structure of these microbial communities is tightly interlaced with ecosystem function. Recycling processes nitrification and dissimilatory nitrate reduction to ammonium (DNRA) serve as a conduit for loss when coupled to the …

The Influence Of Short-Term Events On The Hydrographic And Biological Structure Of The Southwestern Ross Sea, Randolph M. Jones

Dissertations, Theses, and Masters Projects

Relative to the rest of the Southern Ocean, the Ross Sea continental shelf experiences very high productivity and phytoplankton biomass, which supports an extensive food web including high concentrations of upper trophic level biomass. Conventional observational methods, including ship-based sampling, instrumented moorings, satellite imagery, and computer-based modelling, have illustrated the seasonal progression of the phytoplankton bloom over the past four decades. While we have been sampling phytoplankton variability in the Ross Sea on a variety of relatively large scales, with observations at specific locations or times, over spans of time, or at specific depths, our understanding of smaller scales of …

Spread And Interaction Of Epidemics And Information On Adaptive Social Networks, Yunhan Long

Dissertations, Theses, and Masters Projects

The spread of diseases and opinions has profoundly affected the development of human societies. The structure of the underlying social network may change as a result of individuals changing their social connections in response to an ongoing epidemic or opinion spreading, either for self protection or as an expression of personal values. The interaction of spreading processes and the underlying network structure has been a focus of many recent studies. In this dissertation, we construct models to better incorporate heterogeneous responses to disease spread and attempted opinion spread.;We first model the simultaneous spread of an epidemic and awareness about the …

Langevin, Population Density And Moment-Based Modeling Of Local And Global Aspects Of Intercellular Calcium Signaling, Xiao Wang

Dissertations, Theses, and Masters Projects

Markov chain models of the coupled gating of intracellular calcium (Ca 2+) channels are often used to study the stochastic dynamic of local Ca2+ release events and whole cell Ca2+ homeostasis. However, the runtime of the Markov chain description of Ca2+ channel gating is exponential in the number of Ca2+ channel states and may thus result in a combinatorial state space explosion when the number of channel states is large. This dissertation presents several novel stochastic modeling approaches that capture important aspects of Ca 2+ signaling while improving computational efficiency. This dissertation presents several novel stochastic modeling approaches that capture …

Habitat Use Of The Declining Wood Thrush In Coastal Virginia, Vitek Jirinec

Dissertations, Theses, and Masters Projects

No abstract provided.

A Mathematical Model Of Tau Protein Hyperphosphorylation: The Effects Of Kinase Inhibitors As A Theoretical Alzheimer's Disease Therapy, Patrick Neil Blank

Dissertations, Theses, and Masters Projects

No abstract provided.

Spatial Modeling Of A Realized Niche: Investigating The Invasion Of Sweet Fennel (Foeniculum Vulgare Mill) Into Coastal Habitats Of Virginia's Eastern Shore, Kathryn Elizabeth Maccormick

Dissertations, Theses, and Masters Projects

No abstract provided.

Apoptosis And Cell Cycle Regulation As Mechanisms Of Compensation From Notch Signaling Perturbation In The Developing Nervous System Of Xenopus Laevis, Catherine Hope Bianchi

Dissertations, Theses, and Masters Projects

No abstract provided.

The Influence Of Environmental Factors And Resource Availability On Zostera Marina Flowering Intensity, Andrew J. Johnson

Dissertations, Theses, and Masters Projects

Sexual reproduction and the production of seeds are important for the resilience of all angiosperm species. For clonal species, such as the seagrass Zostera marina, resource allocation is complicated because these species reproduce both asexually and sexually, and the factors contributing to allocation to these two processes remains unknown. The goal of this study was, therefore, to investigate the importance of critical light, nutrient, and rhizome resources on Z.

marina sexual reproduction and flowering intensity. To evaluate the importance of sediment nutrients on Z. marina flowering intensity two distinct field manipulative experiments and one field survey were initiated: 1. Sediments …

Developing Methodologies For Studying Elasmobranchs And Other Data-Poor Species, Kristen L. Omori

Dissertations, Theses, and Masters Projects

Fisheries have become increasingly important to manage and conserve, and this is particularly challenging for data-poor species. Elasmobranchs are commonly considered data-poor or data-limited species. Their life history characteristics make their populations susceptible to depletion from fishing pressures and habitat degradation. Thus, it is important to understand the movement patterns and habitat use of the targeted species as well as the models used in the stock assessment for the species. This thesis involves developing techniques and information for data-poor species, such as elasmobranchs. The objectives of this research were to 1) identify the wintering grounds for the cownose rays (Rhinoptera …

The Influence Of Zostera Marina And Ruppia Maritima On Habitat Structure And Function In A Changing Environment In The Chesapeake Bay, Emily D. French

Dissertations, Theses, and Masters Projects

Seagrasses modify the coastal areas they occupy by trapping sediments and improving water clarity, providing habitat for marine animals, and cycling nutrients. Populations are in decline worldwide, and in the lower Chesapeake Bay, U.S., Zostera marina populations are decreasing due to poor water quality and high summertime temperatures. Ruppia maritima, a seagrass that is smaller, but has a greater tolerance of high temperatures than Z. marina, is replacing Z. marina in some areas. This study examined bed characteristics and microbial community structures of each seagrass species, as well as mixed assemblages, at three sites in the lower Chesapeake Bay where …

Diel, Seasonal, And Interannual Patterns In Mesozooplankton Abundance In The Sargasso Sea, Jami Alora Ivory

Dissertations, Theses, and Masters Projects

Temporal changes in mesozooplankton community structure are influenced by a combination of environmental factors. Epipelagic mesozooplankton biomass in the Sargasso Sea has increased over the last two decades, with a related increase in zooplankton-mediated carbon export. Unknown, however, are the patterns and variability at different temporal scales (diel, seasonal, and interannual) in abundance of each major zooplankton taxon, and how these patterns relate to physical and other environmental changes. I enumerated major taxa of mesozooplankton collected from monthly day and night net tows in the epipelagic zone at the Bermuda Atlantic Time-series Study (BATS) site in the Sargasso Sea from …

Phylogeny, Ontogeny And Distribution Of The Ribbonfishes (Lampridiformes: Trachipteridae), Jennifer M. Martin

Dissertations, Theses, and Masters Projects

The ribbonfish family Trachipteridae (Lampridiformes) includes three well-defined genera (Trachipterus, Desmodema, and Zu), which are distributed worldwide throughout the pelagic marine environment as with most families of Lampridiformes, drastic changes in morphology occur throughout ontogeny due to extreme allometric growth. Combined with the rarity of specimens, this has led to the description of different life history stages as different species, rather than as part of the ontogenetic continuum of a single species. There is significant uncertainty concerning the ontogeny, distribution, nomenclature, number and phylogenetic affinity of trachipterid and other lampridiform genera.;The first chapter of my dissertation is a taxonomic review …

Mercury Reduces Avian Reproductive Success Through Direct Embryotoxicity Rather Than Altered Parental Behavior, Stephanie Yen Chin

Dissertations, Theses, and Masters Projects

No abstract provided.

An Investigation Of Hermaphroditism In R Sp Sb 347, Maureen Catherine Farrell

Dissertations, Theses, and Masters Projects

No abstract provided.

Neurocognitive Mechanisms Of Social Influence On Emotion, Emily Catherine Willroth

Dissertations, Theses, and Masters Projects

No abstract provided.

Temperature, Photoperiod, And Life History Traits In Drosophila Subobscura, Heidi Joan Maclean

Dissertations, Theses, and Masters Projects

No abstract provided.

A Model Of Carrying Capacity And Ecosystem Impacts In A Large-Scale, Bivalve-Dominated Agro-Ecosystem: Hard Clam Aquaculture In Cherrystone Inlet, Va, Michael A. Kuschner

Dissertations, Theses, and Masters Projects

With the recent growth of the hard clam aquaculture industry, sites of intensive aquaculture have emerged as large-scale agro-ecosystems where the success of aquaculture production is dynamically linked to ecosystem function. Large scale clam aquaculture operations are associated with a range of potential positive and negative feedbacks related to nutrient dynamics, water and sediment quality, proliferation of macroalgae, and carrying capacity. Quantitative modeling tools are needed to support system-level planning related to site selection, scale of operations, production capacity and ecosystem function. The purpose of this study was to develop a model for Cherrystone Inlet, VA, where one-third (1.9 km2) …