Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Dissertations, Theses, and Masters Projects

Discipline
Keyword
Publication Year

Articles 331 - 360 of 1876

Full-Text Articles in Physical Sciences and Mathematics

Oyster Reef Connectivity Inferred Via Population Genetic Analysis, Brendan Douglas Turley Jan 2015

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 The SNPs were developed from published and unpublished sequencing data and developed to be used on a Fluidigm Biomark.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 …


Developing Methodologies For Studying Elasmobranchs And Other Data-Poor Species, Kristen L. Omori Jan 2015

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 …


Bay Scallop, Argopecten Irradians, Restoration In The Virginia Coastal Bays: The Role Of Predation On Spring Vs Fall Cohort Survival, Erika L. Schmitt Jan 2015

Bay Scallop, Argopecten Irradians, Restoration In The Virginia Coastal Bays: The Role Of Predation On Spring Vs Fall Cohort Survival, Erika L. Schmitt

Dissertations, Theses, and Masters Projects

While the importance o f predation in controlling many natural bivalve populations is well established, it is often overlooked in the restoration strategies for depleted populations. Adult bay scallops {Argopecten irradians concentricus) along the U.S. mid-Atlantic coast spawn multiple times per year, typically once in the early summer and again in the early fall. Larvae generally settle on seagrass leaves to avoid benthic predators, but shift to the sediment surface around 20 mm in size when they become less vulnerable to predation. The objectives o f this study were to 1.) Determine proportional survival o f two distinct size classes …


The Influence Of Zostera Marina And Ruppia Maritima On Habitat Structure And Function In A Changing Environment In The Chesapeake Bay, Emily D. French Jan 2015

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 …


The Reproductive Biology Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, Carissa L. Gervasi Jan 2015

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 …


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 Jan 2015

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) …


The Influence Of Short-Term Events On The Hydrographic And Biological Structure Of The Southwestern Ross Sea, Randolph M. Jones Jan 2015

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 …


Diel, Seasonal, And Interannual Patterns In Mesozooplankton Abundance In The Sargasso Sea, Jami Alora Ivory Jan 2015

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 …


Storm Event Impact On Organic Matter Flux, Composition And Reactivity In Taskinas Creek, Va, Sarah Schillawski Cammer Jan 2015

Storm Event Impact On Organic Matter Flux, Composition And Reactivity In Taskinas Creek, Va, Sarah Schillawski Cammer

Dissertations, Theses, and Masters Projects

Carbon export from the land to the ocean are an important part of the global carbon cycle, linking terrestrial watersheds and the global carbon cycle. Burial of terrestrial organic carbon represents a long term sink for atmospheric CO2. Approximately 0.4 Pg Cy-1 is delivered to the global ocean from rivers, equally divided between POC and DOC. However, the amount of carbon entering the ocean is a small portion of the total amount entering rivers from the terrestrial environment, suggesting a large amount of processing in inland waters and estuaries. Most monitoring efforts have focused the processing of organic matter on …


Spread And Interaction Of Epidemics And Information On Adaptive Social Networks, Yunhan Long Jan 2015

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 …


Some Properties Of Meson Excited States From Lattice Qcd, Ekaterina V. Mastropas Jan 2015

Some Properties Of Meson Excited States From Lattice Qcd, Ekaterina V. Mastropas

Dissertations, Theses, and Masters Projects

The work presented here is devoted to the calculations of the decay constants of the pion and its excited states. All calculations were carried out in the framework of lattice quantum chromodynamics, a well-established formalism of strong interactions enabling the ab initio solution of the theory. After a short introduction and review of the fundamental approaches and methods commonly used in lattice QCD, I provide a detail description of the numerical simulations which were performed at three values of the pion mass between 400 and 700 MeV, using an anisotropic clover fermion action with three flavors of quarks. The results …


Ultracold Rubidium And Potassium System For Atom Chip-Based Microwave And Rf Potentials, Austin R. Ziltz Jan 2015

Ultracold Rubidium And Potassium System For Atom Chip-Based Microwave And Rf Potentials, Austin R. Ziltz

Dissertations, Theses, and Masters Projects

In this dissertation we study the development of microwave and RF near-field potentials for use with atom chip trapped atomic gases. These potentials are inherently spin-dependent, able to target individual spin states simultaneously. In contrast with traditional atom chip potentials, these RF traps can be operated at arbitrary bias magnetic field strengths and thus be combined with magnetic Feshbach resonances. Furthermore, these potentials can strongly suppress the potential roughness that plagues traditional atom chip potentials. We present a dual chamber atom chip apparatus for generating ultracold 87Rb and 39K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 104 87Rb …


Optical Characterization Of Ferromagnetic And Multiferroic Thin-Film Heterostructures, Xin Ma Jan 2015

Optical Characterization Of Ferromagnetic And Multiferroic Thin-Film Heterostructures, Xin Ma

Dissertations, Theses, and Masters Projects

This thesis presents optical characterization of the static and dynamic magnetic interactions in ferromagnetic and multiferroic heterostructures with time-resolved and interface-specific optical techniques. The focus of the thesis is on elucidating the underlying physics of key physical parameters and novel approaches, crucial to the performance of magnetic recording and spintronic devices.;First, time-resolved magneto-optical Kerr effect (TRMOKE) is applied to investigate the spin dynamics in L10 ordered FePt thin films, where perpendicular magnetic anisotropy Ku and intrinsic Gilbert damping alpha0 are determined. Furthermore, the quadratic dependence of Ku and alpha0 on spin-orbit coupling strength xi is demonstrated, where xi is continuously …


Mercury Reduces Avian Reproductive Success Through Direct Embryotoxicity Rather Than Altered Parental Behavior, Stephanie Yen Chin Jan 2015

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

Dissertations, Theses, and Masters Projects

No abstract provided.


Determining The Efficacy Of The Extended Kinetic Method For Determination Of Thermochemical Properties Of Small, High-Entropy, Organic Molecules, Mary Grace Pisano Jan 2015

Determining The Efficacy Of The Extended Kinetic Method For Determination Of Thermochemical Properties Of Small, High-Entropy, Organic Molecules, Mary Grace Pisano

Dissertations, Theses, and Masters Projects

No abstract provided.


Surface-Enhanced Raman And Single-Molecule Spectroscopy Studies Of Fugitive Artists' Pigments, Kristen A. Frano Jan 2015

Surface-Enhanced Raman And Single-Molecule Spectroscopy Studies Of Fugitive Artists' Pigments, Kristen A. Frano

Dissertations, Theses, and Masters Projects

No abstract provided.


Studies Of Molecular Dynamics Of Fmoc Amino Acids Using Solid State Deuteron Nuclear Magnetic Resonance Spectroscopy, Wei Xu Jan 2015

Studies Of Molecular Dynamics Of Fmoc Amino Acids Using Solid State Deuteron Nuclear Magnetic Resonance Spectroscopy, Wei Xu

Dissertations, Theses, and Masters Projects

The purpose of devising and validating models for intramolecular motions for FMOC amino acids is to quantify side chain motion in proteins which plays an important role in understanding biological structure function relations of proteins. In this thesis, spin lattice relaxation times (Ti) of FMOC amino acids were m easured under both static and magic angle spinning (MAS) condition at variable tem peratures. Lower activation energies of the relaxation times than the normal amino acids observed indicate a less sterically crowded environment for the rotation methyl group. A three-site jump model for the methyl group w as developed to fit …


A Mathematical Model Of Tau Protein Hyperphosphorylation: The Effects Of Kinase Inhibitors As A Theoretical Alzheimer's Disease Therapy, Patrick Neil Blank Jan 2015

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.


Development Of A Solid-Supported Glaser-Hay Reaction And Utilization In Conjunction With Unnatural Amino Acids, Jessica S. Lampkowski Jan 2015

Development Of A Solid-Supported Glaser-Hay Reaction And Utilization In Conjunction With Unnatural Amino Acids, Jessica S. Lampkowski

Dissertations, Theses, and Masters Projects

No abstract provided.


Two-Component, Four Reaction Domino Sequence Toward Novel Tricyclic 1,4-Dihydro-2h-Benzo(F)Sochromenes, Yuzhou Chen Jan 2015

Two-Component, Four Reaction Domino Sequence Toward Novel Tricyclic 1,4-Dihydro-2h-Benzo(F)Sochromenes, Yuzhou Chen

Dissertations, Theses, and Masters Projects

The synthesis of complex molecules usually


Providing Efficient Services For Smartphone Applications, Yifan Zhang Jan 2015

Providing Efficient Services For Smartphone Applications, Yifan Zhang

Dissertations, Theses, and Masters Projects

Mobile applications are becoming an indispensable part of people's lives, as they allow access to a broad range of services when users are on the go. We present our efforts towards enabling efficient mobile applications in smartphones. Our goal is to improve efficiency of the underlying services, which provide essential functionality to smartphone applications. In particular, we are interested in three fundamental services in smartphones: wireless communication service, power management service, and location reporting service.;For the wireless communication service, we focus on improving spectrum utilization efficiency for cognitive radio communications. We propose ETCH, a set of channel hopping based MAC …


Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber Jan 2014

Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber

Dissertations, Theses, and Masters Projects

Copepods are the dominant mesozooplankton in the Southern Ocean, but long- term change in their abundance and distribution along the Western Antarctic Peninsula (WAP), a region experiencing rapid climate warming, is unknown. Copepods are also potentially important grazers of phytoplankton in the WAP and contributors to carbon export through production of sinking fecal pellets. I examined summer (January- February) copepod community structure and abundance along the WAP over two decades (1993-2013) and investigated long-term trends in copepod abundance and their relationship with environmental parameters (sea ice, phytoplankton biomass and productivity, climate indices, and sea surface temperature). Copepods comprised on average …


Magneto-Optics And Magneto-Transport Studies On Thin Films For Sensor Applications, Kaida Yang Jan 2014

Magneto-Optics And Magneto-Transport Studies On Thin Films For Sensor Applications, Kaida Yang

Dissertations, Theses, and Masters Projects

Recent progress and interest have bought considerable effort to bear on the synthesis and opportunities of magnetic thin films in different fields. There are applications in many fields, including remote sensing, waveguide applications, hard drive applications, etc. at the College of William and Mary, we have focused on utilizing magnetic thin films in some of these applications and are deeply involved in the optimization process of the thin films.


Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski Jan 2014

Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski

Dissertations, Theses, and Masters Projects

The value of habitats in terms of biological production is of interest to ecologists and resource managers. Seagrasses are a commonly occurring habitat type in shallow marine waters and have been shown to support high abundances of fish and invertebrates. In lower Chesapeake Bay, seagrasses grow in a shallow fringe in the subtidal zone. Although, ample evidence exists for the value of these habitats as foraging and rearing areas for a variety of organisms, the connectivity among species and the benefits derived from these habitats in terms of production have not been well described, especially for small, seasonally occurring finfishes. …


Studies Of Mortality Estimation, Amy Y. Then Jan 2014

Studies Of Mortality Estimation, Amy Y. Then

Dissertations, Theses, and Masters Projects

Instantaneous total mortality rate Z can be partitioned into two components: fishing, F, and natural mortality, M. A number of data-poor methods have been developed to estimate Z, F, and M, and these methods tend to rely on fairly restrictive assumptions as well as on data types that are easy to obtain, e.g., length or other life history information. The overarching goal of this dissertation is to contribute to the advancement of methods for estimating these important and influential stock parameters. The relevant issues and the gaps in knowledge pertaining to these data-poor methods are outlined in the Introduction chapter …


Exploiting Behavioral Biometrics For User Security Enhancements, Nan Zheng Jan 2014

Exploiting Behavioral Biometrics For User Security Enhancements, Nan Zheng

Dissertations, Theses, and Masters Projects

As online business has been very popular in the past decade, the tasks of providing user authentication and verification have become more important than before to protect user sensitive information from malicious hands. The most common approach to user authentication and verification is the use of password. However, the dilemma users facing in traditional passwords becomes more and more evident: users tend to choose easy-to-remember passwords, which are often weak passwords that are easy to crack. Meanwhile, behavioral biometrics have promising potentials in meeting both security and usability demands, since they authenticate users by "who you are", instead of "what …


Effective Resource And Workload Management In Data Centers, Lei Lu Jan 2014

Effective Resource And Workload Management In Data Centers, Lei Lu

Dissertations, Theses, and Masters Projects

The increasing demand for storage, computation, and business continuity has driven the growth of data centers. Managing data centers efficiently is a difficult task because of the wide variety of datacenter applications, their ever-changing intensities, and the fact that application performance targets may differ widely. Server virtualization has been a game-changing technology for IT, providing the possibility to support multiple virtual machines (VMs) simultaneously. This dissertation focuses on how virtualization technologies can be utilized to develop new tools for maintaining high resource utilization, for achieving high application performance, and for reducing the cost of data center management.;For multi-tiered applications, bursty …


Enhancement Of Ms Signal Processing For Improved Cancer Biomarker Discovery, Qian Si Jan 2014

Enhancement Of Ms Signal Processing For Improved Cancer Biomarker Discovery, Qian Si

Dissertations, Theses, and Masters Projects

Technological advances in proteomics have shown great potential in detecting cancer at the earliest stages. One way is to use the time of flight mass spectroscopy to identify biomarkers, or early disease indicators related to the cancer. Pattern analysis of time of flight mass spectra data from blood and tissue samples gives great hope for the identification of potential biomarkers among the complex mixture of biological and chemical samples for the early cancer detection. One of the keys issues is the pre-processing of raw mass spectra data. A lot of challenges need to be addressed: unknown noise character associated with …


Amine- And Sulfide-Sensing Copper(I) Iodide Films And The Structure, Dynamics, And Photophysics In The Copper(I) Iodide-Tetrahydrothiophene System, Kylie Marie Henline Jan 2014

Amine- And Sulfide-Sensing Copper(I) Iodide Films And The Structure, Dynamics, And Photophysics In The Copper(I) Iodide-Tetrahydrothiophene System, Kylie Marie Henline

Dissertations, Theses, and Masters Projects

No abstract provided.


Studying And Enabling Reuse In Android Mobile Apps, Andrew Steven Holtzhauer Jan 2014

Studying And Enabling Reuse In Android Mobile Apps, Andrew Steven Holtzhauer

Dissertations, Theses, and Masters Projects

No abstract provided.