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Articles 31 - 47 of 47

Full-Text Articles in Physical Sciences and Mathematics

Multimodal Non-Rigid Registration For Image-Guided Head And Neck Surgery, Michael Lawrence Weissberger Jan 2010

Multimodal Non-Rigid Registration For Image-Guided Head And Neck Surgery, Michael Lawrence Weissberger

Dissertations, Theses, and Masters Projects

No abstract provided.


The Life History Of Longnose Gar, Lepisosteus Osseus, An Apex Predator In The Tidal Waters Of Virginia, Patrick E. Mcgrath Jan 2010

The Life History Of Longnose Gar, Lepisosteus Osseus, An Apex Predator In The Tidal Waters Of Virginia, Patrick E. Mcgrath

Dissertations, Theses, and Masters Projects

Longnose gar (Lepisosteus osseus) inhabit all of the major tributaries of Chesapeake Bay in Virginia, extending from fresh to estuarine waters. Literature concerning longnose gar from tidal environments is limited and this is study concerns important aspects of the life history (e.g., growth, reproduction, dimorphism, movements, and diet). Age, growth, and reproduction are important life history aspects for understanding the biology of fishes and may be affected by the environment in which an individual lives. This study found no differences in the age, growth, and fecundity parameters between longnose gar from tidal portions of Chesapeake Bay tributaries and previous studies …


Incorporating Industry Based Dredge Surveys Into The Assessment Of Sea Scallops, Placopecten Magellanicus, David B. Rudders Jan 2010

Incorporating Industry Based Dredge Surveys Into The Assessment Of Sea Scallops, Placopecten Magellanicus, David B. Rudders

Dissertations, Theses, and Masters Projects

Cooperative research utilizing industry vessels represents a viable approach to acquire the data necessary to meet the increasing needs associated with the modern management of marine resources. This dissertation addresses a variety of topics associated with the integration of commercial vessels into the stock assessment of the sea scallop, Placopecten magellanicus. In this study we evaluate the efficacy of utilizing industry vessels with respect to topics that range from rotational closed area survey design, sampling gear evaluation as well as an experiment that broadens the scale of the traditional use of industry vessels in this fishery and provides data to …


Accounting For Undesirable Outputs In Productivity Measurements: Application To The California-Oregon Drift Gillnet Fishery, Tara L. Scott Jan 2010

Accounting For Undesirable Outputs In Productivity Measurements: Application To The California-Oregon Drift Gillnet Fishery, Tara L. Scott

Dissertations, Theses, and Masters Projects

Many production activities typically produce undesirable outputs, e.g., the production of the pollutant sulfur dioxide in the generation of electricity. Traditional economic metrics may overstate the efficiency and productivity of these production activities by failing to account for the undesirable outputs. These omissions can lead to conclusions that are biased against resource conservation and protection. Many fisheries capture their target species concomitantly with undesirable outputs such as bycatch of juvenile fish, marine mammals, sea birds, and sea turtles. One such fishery is the California-Oregon (CA/OR) drift gillnet fishery (DGNF), which incidentally takes protected species, such as sea turtles and marine …


The Logarithmic Method And The Solution To The Tp2-Completion Problem, Shahla Nasserasr Jan 2010

The Logarithmic Method And The Solution To The Tp2-Completion Problem, Shahla Nasserasr

Dissertations, Theses, and Masters Projects

A matrix is called TP2 if all 1-by-1 and 2-by-2 minors are positive. A partial matrix is one with some of its entries specified, while the remaining, unspecified, entries are free to be chosen. A TP2-completion, of a partial matrix T , is a choice of values for the unspecified entries of T so that the resulting matrix is TP2. The TP2-completion problem asks which partial matrices have a TP2-completion. A complete solution is given here. It is shown that the Bruhat partial order on permutations is the inverse of a certain natural partial order induced by TP2 matrices and …


Partial Year Tagging Models: Accounting For Changing Tag Visibility And Delayed Mixing, Lynn Waterhouse Jan 2010

Partial Year Tagging Models: Accounting For Changing Tag Visibility And Delayed Mixing, Lynn Waterhouse

Dissertations, Theses, and Masters Projects

No abstract provided.


Integrating Space-And Time-Scales Of Sediment-Transport For Poverty Bay, New Zealand, Aaron J. Bever Jan 2010

Integrating Space-And Time-Scales Of Sediment-Transport For Poverty Bay, New Zealand, Aaron J. Bever

Dissertations, Theses, and Masters Projects

Poverty Bay is a small embayment located in the middle of the Waipaoa River Sedimentary Dispersal System (WSS) on the eastern coast of the north island of New Zealand. Within this dispersal system, a large multidisciplinary study was focused on determining the sediment routing from the source within the headwaters to the locations of sediment accumulation on the continental shelf and slope. Poverty Bay acts as the land to sea transition area in the WSS, and as such significantly modifies the fluvial sedimentary signal before it is exported to the continental shelf. Until this study, little hydrodynamic or sediment-transport work …


Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz Jan 2010

Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz

Dissertations, Theses, and Masters Projects

Antarctic seabirds including Adelie penguins (Pygoscelis adeliae), south polar skuas (Catharacta maccormicki), southern giant petrels (Macronectes gigantus) are high trophic level predators that accumulate persistent organic pollutants (POPs) present in the food webs in which they forage. Little is known about the levels of POPs in some Antarctic organisms (e.g. southern giant petrels), as well as the long-term trends of POPs in the Antarctic ecosystem. Samples from all three seabird species were collected post mortem, including eggs, from the Western Antarctic Peninsula (WAP) and in the Ross Sea throughout the austral summer breeding seasons of 2004--2006. The samples were analyzed …


Spatial And Temporal Patterns In Erosional And Depositional Processes: Physical And Biological Controls In The York River, Chesapeake Bay, Virginia, Cielomar Rodríguez-Calderon Jan 2010

Spatial And Temporal Patterns In Erosional And Depositional Processes: Physical And Biological Controls In The York River, Chesapeake Bay, Virginia, Cielomar Rodríguez-Calderon

Dissertations, Theses, and Masters Projects

No abstract provided.


The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba Jan 2010

The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba

Dissertations, Theses, and Masters Projects

Zooplankton play a key role in the cycling of dissolved organic matter (DOM) and inorganic nutrients. The factors that affect these processes, however, are not fully understood. I measured the effects of various diets on DOM and inorganic nutrient production by the copepod Acartia tonsa and the heterotrophic dinoflagellate Oxyrrhis marina, and explored the mechanisms of nutrient release from copepods. Copepods feeding on a mixed diet, the preferred diet of most copepods, had significantly lower dissolved organic carbon (DOC), ammonium (NH4+), and total dissolved nitrogen (TDN) release rates compared to feeding on a carnivorous or herbivorous diet. Thus, copepod feeding …


Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes, Joshua Erold Robert Abelard Jan 2010

Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes, Joshua Erold Robert Abelard

Dissertations, Theses, and Masters Projects

No abstract provided.


Quantum Information Dynamics, Jeffrey Yepez Jan 2010

Quantum Information Dynamics, Jeffrey Yepez

Dissertations, Theses, and Masters Projects

Presented is a study of quantum entanglement from the perspective of the theory of quantum information dynamics. We consider pairwise entanglement and present an analytical development using joint ladder operators, the sum of two single-particle fermionic ladder operators. This approach allows us to write down analytical representations of quantum algorithms and to explore quantum entanglement as it is manifested in a system of qubits.;We present a topological representation of quantum logic that views entangled qubit spacetime histories (or qubit world lines) as a generalized braid, referred to as a super-braid. The crossing of world lines may be either classical or …


Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke Jan 2010

Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke

Dissertations, Theses, and Masters Projects

Oyster shell for native oyster reef restoration is scarce in Chesapeake Bay and other estuaries (Chapter 1). Consequently, alternative substrates merit consideration in oyster restoration. This dissertation examines the suitability of shell alternatives, including granite, concrete, limestone marl, concrete modules and reefballs with reef surveys and experiments in the Rappahannock and Lynnhaven Rivers of Chesapeake Bay. Oyster recruitment, growth, survival, density, biomass, condition, and disease stress, as well as reef accretion and persistence, were measured. In the Lynnhaven River, intertidal riprap had a mean density of 978 oysters m-2 (165 g AFDM m-2) and peak densities > 2000 oysters m-2 (Chapter …


Quantifying The Ecosystem Role Of A Suspension And A Facultative Deposit Feeding Bivalve In The New River Estuary, Nc: With Responses To Changes In Nutrient And Sediment Inputs, Heather Marie Wiseman Jan 2010

Quantifying The Ecosystem Role Of A Suspension And A Facultative Deposit Feeding Bivalve In The New River Estuary, Nc: With Responses To Changes In Nutrient And Sediment Inputs, Heather Marie Wiseman

Dissertations, Theses, and Masters Projects

No abstract provided.


Acoustics Of Anthropogenic Habitats: The Impact Of Noise Pollution On Eastern Bluebirds, Caitlin Rebecca Kight Jan 2010

Acoustics Of Anthropogenic Habitats: The Impact Of Noise Pollution On Eastern Bluebirds, Caitlin Rebecca Kight

Dissertations, Theses, and Masters Projects

An increasing number of habitats are affected by anthropogenic noise pollution, which is often louder, has a different frequency emphasis, and may occur over a different temporal scale, than natural noise. An increasing number of studies indicate that acoustically-communicating animals in such areas can modify their vocalizations in order to make themselves heard over the noise, but many questions still remain, including: How taxonomically widespread is vocal flexibility in response to anthropogenic noise, and do all vocally flexible species employ the same mechanisms to escape acoustic masking? Are there fitness repercussions for living, communicating, and breeding in noisy habitats? and, …


The Lateral Extent And Spatial Variation Of Mercury Exposure In Birds And Their Prey Near A Polluted River, Mikaela Gioia Selene Howie Jan 2010

The Lateral Extent And Spatial Variation Of Mercury Exposure In Birds And Their Prey Near A Polluted River, Mikaela Gioia Selene Howie

Dissertations, Theses, and Masters Projects

No abstract provided.


Multifunctional Polymer Synthesis And Incorporation Of Gadolinium Compounds And Modified Tungsten Nanoparticles For Improvement Of Radiation Shielding For Use In Outer Space, Emily Grace Harbert Jan 2010

Multifunctional Polymer Synthesis And Incorporation Of Gadolinium Compounds And Modified Tungsten Nanoparticles For Improvement Of Radiation Shielding For Use In Outer Space, Emily Grace Harbert

Dissertations, Theses, and Masters Projects

No abstract provided.