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Physical Sciences and Mathematics

Dissertations, Theses, and Masters Projects

2003

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Comparison Of Mussel-Bed Faunas At Blake Ridge And Florida Escarpment Seeps, Kathleen Elizabeth Knick Jan 2003

Comparison Of Mussel-Bed Faunas At Blake Ridge And Florida Escarpment Seeps, Kathleen Elizabeth Knick

Dissertations, Theses, and Masters Projects

No abstract provided.


Use Of Ponds And Lakes By Resident Canada Geese, Phillip D. West Jan 2003

Use Of Ponds And Lakes By Resident Canada Geese, Phillip D. West

Dissertations, Theses, and Masters Projects

No abstract provided.


Domain And Type Enforcement In Linux, Serge Edward Hallyn Jan 2003

Domain And Type Enforcement In Linux, Serge Edward Hallyn

Dissertations, Theses, and Masters Projects

Domain and Type Enforcement (DTE) is a simple and well-known access control system, which has been used at the microkernel level in SPIN, the kernel level in Unix, and the user-space library level in CORBA. This work implements DTE as a Linux Security Module, and provides tools for the composition and analysis of policies. The goal is to bring Mandatory Access Control in Linux to the level of ease of use of cryptography tools and libraries.;Tools have been created to edit DTE policies and query transitions through different privilege levels. A subtle modification of the Bell LaPadula (BLP) access control …


Laboratory Oxide Coatings: Physical Form And Surface Chemistry, Kea U. Duckenfield Jan 2003

Laboratory Oxide Coatings: Physical Form And Surface Chemistry, Kea U. Duckenfield

Dissertations, Theses, and Masters Projects

The impact of dissolved trace metals on aquatic ecosystems and human health is controlled by sorption, i.e., binding to the surfaces of environmental particles. Since many environmental particles are coated with highly reactive substances, and since discrepancies in trace metal sorption behavior persist between oxides developed in the laboratory and environmental oxide phases, it was hypothesized that the physical form of oxide coatings may influence the chemical properties of the coated particle. Therefore, relationships between the physical forms of several different Fe(III) oxide coatings and the Cu(II) sorption behavior of the coated solids were investigated in comparison with the component …


Mechanistic Studies On Chlorinated Polymeric Systems, Jing Zhang Jan 2003

Mechanistic Studies On Chlorinated Polymeric Systems, Jing Zhang

Dissertations, Theses, and Masters Projects

No abstract provided.


Inverse Model Analysis Of Plankton Food Webs In The North Atlantic And Western Antarctic Peninsula, Robert M. Daniels Jan 2003

Inverse Model Analysis Of Plankton Food Webs In The North Atlantic And Western Antarctic Peninsula, Robert M. Daniels

Dissertations, Theses, and Masters Projects

No abstract provided.


Taxonomic Composition And Growth Rates Of Phytoplankton Assemblages At The Subtropical Convergence East Of New Zealand, Liza M. Delizo Jan 2003

Taxonomic Composition And Growth Rates Of Phytoplankton Assemblages At The Subtropical Convergence East Of New Zealand, Liza M. Delizo

Dissertations, Theses, and Masters Projects

No abstract provided.


Automated Fish Species Classification Using Artificial Neural Networks And Autonomous Underwater Vehicles, Daniel Foster Doolittle Jan 2003

Automated Fish Species Classification Using Artificial Neural Networks And Autonomous Underwater Vehicles, Daniel Foster Doolittle

Dissertations, Theses, and Masters Projects

No abstract provided.


Analysis Of Prey Selection In Black Skimmer, Rynchops Niger, Adults And Chicks Using Continuous Video Monitoring, Renae Joyce Held Jan 2003

Analysis Of Prey Selection In Black Skimmer, Rynchops Niger, Adults And Chicks Using Continuous Video Monitoring, Renae Joyce Held

Dissertations, Theses, and Masters Projects

No abstract provided.


Metal Concentrations In Deep-Sea Mussels From A Hydrothermal Vent And Cold Seep, Shana Rapoport Jan 2003

Metal Concentrations In Deep-Sea Mussels From A Hydrothermal Vent And Cold Seep, Shana Rapoport

Dissertations, Theses, and Masters Projects

No abstract provided.


Location Management In A Mobile Object Runtime Environment, Andriy Fedorov Jan 2003

Location Management In A Mobile Object Runtime Environment, Andriy Fedorov

Dissertations, Theses, and Masters Projects

No abstract provided.


Chemical Bonding In Hard And Elastic Amorphous Carbon-Nitride Films, W. Jason Gammon Jan 2003

Chemical Bonding In Hard And Elastic Amorphous Carbon-Nitride Films, W. Jason Gammon

Dissertations, Theses, and Masters Projects

In this study, the chemical bonding in hard and elastic amorphous carbon nitride (a-CNx) films is investigated with x-ray photoelectron spectroscopy (XPS) and 15N, 13C, and 1H nuclear magnetic resonance (NMR) spectroscopy. The films were deposited by DC Magnetron sputtering in a pure nitrogen discharge on Si(001) substrates at 300--400??C. Nanoindentation measurements reveal an elastic modulus of ∼50 GPa and a hardness of ∼5 GPa, thus confirming our films are highly elastic but resist plastic deformation.;Our 13C NMR study demonstrates the absence of sp 3-bonded carbon in this material. Collectively, our N(1s) XPS, 13C NMR, and 15N NMR data suggest …


Power Considerations For Memory-Related Microarchitecture Designs, Zhichun Zhu Jan 2003

Power Considerations For Memory-Related Microarchitecture Designs, Zhichun Zhu

Dissertations, Theses, and Masters Projects

The fast performance improvement of computer systems in the last decade comes with the consistent increase on power consumption. In recent years, power dissipation is becoming a design constraint even for high-performance systems. Higher power dissipation means higher packaging and cooling cost, and lower reliability. This Ph.D. dissertation will investigate several memory-related design and optimization issues of general-purpose computer microarchitectures, aiming at reducing the power consumption without sacrificing the performance. The memory system consumes a large percentage of the system's power. In addition, its behavior affects the processor power consumption significantly. In this dissertation, we propose two schemes to address …


Avian Communities Of Created And Natural Wetlands: Saltmarshes Of Southeast Virginia, David William Desrochers Jan 2003

Avian Communities Of Created And Natural Wetlands: Saltmarshes Of Southeast Virginia, David William Desrochers

Dissertations, Theses, and Masters Projects

No abstract provided.


An Analysis Of Wetland Patterns And Functions At The Watershed And Sub-Watershed Scales, With *Policy Applications, Jennifer Newton Bissonnette Jan 2003

An Analysis Of Wetland Patterns And Functions At The Watershed And Sub-Watershed Scales, With *Policy Applications, Jennifer Newton Bissonnette

Dissertations, Theses, and Masters Projects

This dissertation addresses the need to define potential impacts of recent and proposed changes in federal wetland regulation in a quantifiable manner. Consideration was made not only of total wetland acreage and wetland types that could sustain losses, but also to categorize the effect such losses would have in terms of wetland functions, at the watershed scale. This work took a Geographic Information Systems (GIS) approach, and included employing a best-professional judgment model for scoring habitat, water quality and flood attenuation functions to determine potential cumulative impacts; a water quality study which related wetland and watershed variables to nutrient and …


A Mycobacterium-Inducible Nramp In Striped Bass Morone Saxatilis, Erin Jeffrey Burge Jan 2003

A Mycobacterium-Inducible Nramp In Striped Bass Morone Saxatilis, Erin Jeffrey Burge

Dissertations, Theses, and Masters Projects

In mammals, the natural resistance-associated macrophage protein 1 gene, Nramp1, plays a major role in resistance to mycobacterial infections. Chesapeake Bay (USA) striped bass, Morone saxatilis, are currently experiencing an epizootic of mycobacteriosis that threatens the health of this ecologically and economically important species. This dissertation characterizes an Nramp gene in this species (MsNramp ) and provide evidence for induction following Mycobacterium exposure. The striped bass MsNramp gene and 554 amino acid sequence contain all the signal features of the Nramp family, including a topology of 12 transmembrane domains (TM), the transport protein specific 'binding-protein-dependent transport system inner membrane component …


Microbial Dynamics And Biogeochemistry In The North Pacific Subtropical Gyre, Matthew J. Church Jan 2003

Microbial Dynamics And Biogeochemistry In The North Pacific Subtropical Gyre, Matthew J. Church

Dissertations, Theses, and Masters Projects

The research presented in this dissertation describes the influence of planktonic bacterial growth on upper ocean organic matter dynamics in the North Pacific Subtropical Gyre (NPSG). Examination of the temporal dynamics in dissolved organic matter (DOM) was coupled with investigations that targeted the influence of heterotrophic bacterial production (HBP) on organic matter fluxes in the NPSG. Nine cruises to the Hawaii Ocean Time-series field site Station ALOHA revealed that HBP accounted for a large flux of organic carbon in the upper ocean of the NPSG. HBP was significantly enhanced by sunlight, with photoenhancement of HBP accounting for 3.2 mol C …


Controls On The Delivery Of Fluvial Sediment To The Coastal Ocean: The Salinas River, California, Katherine L. Farnsworth Jan 2003

Controls On The Delivery Of Fluvial Sediment To The Coastal Ocean: The Salinas River, California, Katherine L. Farnsworth

Dissertations, Theses, and Masters Projects

To estimate delivery to the coastal ocean, a global river database was assembled. An estimated 35,000 km3 of freshwater, 4 * 10 6 tonnes of dissolved solids and 18.6 * 106 tonnes of suspended sediment are delivered annually. The global delivery of fluvial water and sediment, both suspended and dissolved, is dominated by Southeast Asia, due to the unique climatic, geologic and geomorphic character of the rivers in this region. Over 30% of the global freshwater and dissolved solid discharge, and an astounding 70% of the suspended sediment originate in this region. The Salinas River, central California, was the focus …


A Theoretical And Experimental Study Of Allee Effects, Joanna Gascoigne Jan 2003

A Theoretical And Experimental Study Of Allee Effects, Joanna Gascoigne

Dissertations, Theses, and Masters Projects

Allee effects occur when fitness suffers at low population size or density. This can lead to reduced population growth rate and a critical density below which extinction occurs. Allee effects can occur in reproduction or survival. Critical densities are higher in reproductive Allee effects than in juvenile survival Allee effects, making reproductive Allee effects more severe (higher extinction probability). In terms of the critical Allee effect threshold, reproductive Allee effects are more severe in r-selected populations, while juvenile survival Allee effects are more severe in K-selected populations. For populations with negative density dependence, there is a maximum critical Allee threshold, …


Polycyclic Aromatic Hydrocarbon Sources And Distribution In An Urban Estuary, Shelby E. Walker Jan 2003

Polycyclic Aromatic Hydrocarbon Sources And Distribution In An Urban Estuary, Shelby E. Walker

Dissertations, Theses, and Masters Projects

As part of the assessment of the potential risk posed by contaminated sediments to the environment and human health, the United States Environmental Protection Agency (USEPA) is developing a set of sediment quality criteria (SQC) that are based on equilibrium partitioning (EqP). While EqP theory has often been used to predict contaminant concentrations within a factor of two for a range of sediment types, substantial deviations from predicted values have also been documented. The objective of this research was to evaluate the influence of PAH source on PAH sediment-pore water partitioning and distribution in sediments. The Elizabeth River is one …


Diet Of The Sandbar Shark, Carcharhinus Plumbeus, In Chesapeake Bay And Adjacent Waters, Julia K. Ellis Jan 2003

Diet Of The Sandbar Shark, Carcharhinus Plumbeus, In Chesapeake Bay And Adjacent Waters, Julia K. Ellis

Dissertations, Theses, and Masters Projects

The sandbar shark, Carcharhinus plumbeus, is the most abundant large coastal shark in the temperate and tropical waters of the northwest Atlantic Ocean. The Chesapeake Bay, Virginia and adjacent waters serve as a nursery ground for C. plumbeus as well as many other fauna. Characterizing the diet of a higher trophic level predator such as the sandbar shark sheds light on a small portion of the temporally and spatially complex food web in the Bay. This study describes the diet of the sandbar shark, highlighting differences in diet within various portions of the nursery area, as well as ontogenetic changes …


Historical Diet Analysis Of Loggerhead (Caretta Caretta) And Kemp's Ridley (Lepidochelys Kempi) Sea Turtles In Virginia, Erin E. Seney Jan 2003

Historical Diet Analysis Of Loggerhead (Caretta Caretta) And Kemp's Ridley (Lepidochelys Kempi) Sea Turtles In Virginia, Erin E. Seney

Dissertations, Theses, and Masters Projects

The Chesapeake Bay and coastal waters of Virginia, U.S.A. serve as foraging grounds for loggerhead (Caretta caretta) and Kemp’s ridley (Lepidochelys kempi) sea turtles from approximately May to October each year. Both loggerheads and Kemp’s ridleys are known to feed primarily on benthic invertebrates as juveniles and adults, but specific prey preferences vary between geographic regions. The Virginia Institute of Marine Science Sea Turtle Program has collected diet data and gut samples from stranded and incidentally caught sea turtles in Virginia since 1979. Examination of turtles that stranded in Virginia during the late 1970s and early 1980s indicated that loggerheads …


A Genetic Analysis Of The Intraspecific Relationships Of Tropical Marine Shorefishes Common To Bermuda And The Southeastern Atlantic Coast Of The United States, Kelly R. Johnson Jan 2003

A Genetic Analysis Of The Intraspecific Relationships Of Tropical Marine Shorefishes Common To Bermuda And The Southeastern Atlantic Coast Of The United States, Kelly R. Johnson

Dissertations, Theses, and Masters Projects

No abstract provided.


Sublethal Effects Of Sediment Contamination On An Estuarine Amphipod, Bruce W. Vogt Jan 2003

Sublethal Effects Of Sediment Contamination On An Estuarine Amphipod, Bruce W. Vogt

Dissertations, Theses, and Masters Projects

No abstract provided.


Ecosystem Gas Exchange In Natural And Created Tidal Salt Marshes Of Tidewater, Virginia, Molly Mitchell Roggero Jan 2003

Ecosystem Gas Exchange In Natural And Created Tidal Salt Marshes Of Tidewater, Virginia, Molly Mitchell Roggero

Dissertations, Theses, and Masters Projects

No abstract provided.


Relationships Between Watershed Characteristics And Base Flow Nutrient Discharges To Eastern Shore Coastal Lagoons, Virginia, Jennifer Wu Stanhope Jan 2003

Relationships Between Watershed Characteristics And Base Flow Nutrient Discharges To Eastern Shore Coastal Lagoons, Virginia, Jennifer Wu Stanhope

Dissertations, Theses, and Masters Projects

No abstract provided.


Bacterial Properties And Dissolved Organic Matter Distributions In The Black Sea, Jessica A. Morgan Jan 2003

Bacterial Properties And Dissolved Organic Matter Distributions In The Black Sea, Jessica A. Morgan

Dissertations, Theses, and Masters Projects

No abstract provided.


Biology Of Mated Triploid Crassostrea Ariakensis In Multiple Environments: Gametogenesis, Sex Ratio, Disease Prevalence, And Reversion, Alan J. Erskine Jan 2003

Biology Of Mated Triploid Crassostrea Ariakensis In Multiple Environments: Gametogenesis, Sex Ratio, Disease Prevalence, And Reversion, Alan J. Erskine

Dissertations, Theses, and Masters Projects

No abstract provided.


A Genetic Investigation Of Population Structure And Phylogenetics Of The Benthic Polychaete Paraprionospio Pinnata In Chesapeake Bay, Julie Beck Stubbs Jan 2003

A Genetic Investigation Of Population Structure And Phylogenetics Of The Benthic Polychaete Paraprionospio Pinnata In Chesapeake Bay, Julie Beck Stubbs

Dissertations, Theses, and Masters Projects

No abstract provided.


Persistent Organic Pollutants At The Base Of The Antarctic Marine Food Web, Amy Lee Chiuchiolo Jan 2003

Persistent Organic Pollutants At The Base Of The Antarctic Marine Food Web, Amy Lee Chiuchiolo

Dissertations, Theses, and Masters Projects

No abstract provided.