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Habitat Utilization And Salinity Tolerance Of The Sandbar Shark, Carcharhinus Plumbeus, In Virginia, Leonard Pace
Habitat Utilization And Salinity Tolerance Of The Sandbar Shark, Carcharhinus Plumbeus, In Virginia, Leonard Pace
Dissertations, Theses, and Masters Projects
No abstract provided.
Size-Selectivity Of The Commercial Sea Scallop (Placopecten Magellanicus) Dredge: Evaluation The Performance Of The New Bedford Style Dredge Configured With 4-Inch Rings And A 10-Inch Twine Top Using The Select Model, Noelle Yochum
Dissertations, Theses, and Masters Projects
A size-selectivity curve was constructed to characterize the performance of the New Bedford style Atlantic sea scallop (Placopecten magellanicus) dredge when it is configured to meet the requirements of Amendment #10 to the Sea Scallop Fishery Management Plan. The curve was generated using the SELECT model on catch-at-length data, obtained by simultaneously towing a New Bedford style dredge and a non-selective National Marine Fisheries Service sea scallop survey dredge from commercial scallop vessels. Data were collected during three cruises in the Northwest Atlantic between 2005 and 2006. One cruise was completed in Georges Bank (Groundfish Closed Area II) and two …
Peroxynitrite Oxidation Of Aromatic Thiols: Characterization Of The Products Formed Through Oxidation Of Thionitrobenzoic Acid And Thionitropyridine By Peroxynitrite, Catherine Balchunas Mall
Peroxynitrite Oxidation Of Aromatic Thiols: Characterization Of The Products Formed Through Oxidation Of Thionitrobenzoic Acid And Thionitropyridine By Peroxynitrite, Catherine Balchunas Mall
Dissertations, Theses, and Masters Projects
No abstract provided.
Migratory And Spawning Behavior Of American Shad In The James River, Virginia, Aaron W. Aunins
Migratory And Spawning Behavior Of American Shad In The James River, Virginia, Aaron W. Aunins
Dissertations, Theses, and Masters Projects
No abstract provided.
Measurement Of Electroweak Asymmetries In Vector Electron Positron Scattering At 0.1 Less Than Q(2) Less Than 0.4 (Gev/C)(2), Jeffery A. Secrest
Measurement Of Electroweak Asymmetries In Vector Electron Positron Scattering At 0.1 Less Than Q(2) Less Than 0.4 (Gev/C)(2), Jeffery A. Secrest
Dissertations, Theses, and Masters Projects
This work is based on the first engineering run of the G 0 experiment from October 2002 though January 2003 in Hall C at Jefferson Lab. The G0 experiment will be the first to measure the weak neutral form factors: GEZ( Q2), GMZ( Q2) and GAe( Q2) and to extract the proton's strange form factors: GEs(Q2) and GMs(Q 2) via a Rosenbluth separation over a range of Q 2 (0.1--1.0 (GeV/c)2). This will require four sets of measurements: forward angle measurements with a proton target, and three sets of backward angle measurements with a hydrogen and deuterium target. The measurements …
Incorporating Space Into Stock Assessments Of Marine Species, John F. Walter
Incorporating Space Into Stock Assessments Of Marine Species, John F. Walter
Dissertations, Theses, and Masters Projects
Spatial management of marine resources requires population dynamic parameters in much greater spatial detail than traditional stock assessments provide. This dissertation presents a suite of methods to improve the spatial prediction of population abundance, fishing and natural mortality and to make greater use of commercial catch data. The main objectives of this dissertation are to determine the efficacy of using the vast amount of data collected by on-board observers on commercial vessels in model-based estimation of abundance and to use the spatial autocorrelation to improve resource mapping and abundance estimation. The first paper presents a methodology for improving variogram estimation …
Sources And Composition Of Particulate Organic Matter In The Sacramento-San Joaquin River Delta, California, Vicki Pilon
Sources And Composition Of Particulate Organic Matter In The Sacramento-San Joaquin River Delta, California, Vicki Pilon
Dissertations, Theses, and Masters Projects
Determining organic matter sources and their availability to higher organisms is essential to better understanding the link between organic matter (OM) dynamics and secondary production, particularly in highly-disturbed river-delta systems. The San Francisco Bay and its associated Delta, is one of the most modified aquatic systems, and is the focus of an ongoing restoration effort. Particulate organic matter (POM) and surficial sediments were collected in the Sacramento-San Joaquin River Delta, CA to document temporal and spatial variations in biochemical, (total protein, carbohydrate and lipid), lipid biomarker, and total hydrolysable amino acid (THAA) composition. Sources, composition and nutritional quality of OM …
Physical Processes Behind Delta Propagation And Flood Layer Dynamics, Po River, Italy, Aaron J. Bever
Physical Processes Behind Delta Propagation And Flood Layer Dynamics, Po River, Italy, Aaron J. Bever
Dissertations, Theses, and Masters Projects
Rivers discharge around 20 billion tonnes of sediment to the coastal ocean each year (Milliman and Syvitski, 1992). Many supply dominated rivers possess large subareal and subaqueous deltas, whose growth depends on the physical processes controlling sediment deposition or removal. There has yet to be a complete understanding of how short term processes such as settling from buoyant plumes, wave/current resuspension, and transport by currents and gravity flows, interact to produce the depositional products that develop over varying timescales. The Po River in Northern Italy forms a substantial delta in the Adriatic Sea. It has five distributary mouths, and is …
Automated Peak Identification For Time -Of -Flight Mass Spectroscopy, Haijian Chen
Automated Peak Identification For Time -Of -Flight Mass Spectroscopy, Haijian Chen
Dissertations, Theses, and Masters Projects
The high throughput capabilities of protein mass fingerprints measurements have made mass spectrometry one of the standard tools for proteomic research, such as biomarker discovery. However, the analysis of large raw data sets produced by the time-of-flight (TOF) spectrometers creates a bottleneck in the discovery process. One specific challenge is the preprocessing and identification of mass peaks corresponding to important biological molecules. The accuracy of mass assignment is another limitation when comparing mass fingerprints with databases.;We have developed an automated peak picking algorithm based on a maximum likelihood approach that effectively and efficiently detects peaks in a time-of-flight secondary ion …
Real -Time Retinex Image Enhancement: Algorithm And Architecture Optimizations, Glenn Derrick Hines
Real -Time Retinex Image Enhancement: Algorithm And Architecture Optimizations, Glenn Derrick Hines
Dissertations, Theses, and Masters Projects
The field of digital image processing encompasses the study of algorithms applied to two-dimensional digital images, such as photographs, or three-dimensional signals, such as digital video. Digital image processing algorithms are generally divided into several distinct branches including image analysis, synthesis, segmentation, compression, restoration, and enhancement. One particular image enhancement algorithm that is rapidly gaining widespread acceptance as a near optimal solution for providing good visual representations of scenes is the Retinex.;The Retinex algorithm performs a non-linear transform that improves the brightness, contrast and sharpness of an image. It simultaneously provides dynamic range compression, color constancy, and color rendition. It …
Studies In Cpt Violation And 331 Models, David L. Anderson
Studies In Cpt Violation And 331 Models, David L. Anderson
Dissertations, Theses, and Masters Projects
The Standard Model of particles and fields has been around for about 30 years, and has been remarkably successful. However, it is widely believed to be incomplete, and theorists have studied various extensions to the model. These extensions can take many forms. An example of this is the framework Colladay and Kostelecky have proposed for studying Lorentz and CPT violation in a natural extension of the Standard Model. We determined the first bounds on the parameters in the Higgs sector. The bounds on the CPT---even asymmetric coefficients arise from the one-loop contributions to the photon propagator, those from the CPT---even …
Optical Characterization Of Ferromagnetic Heterostructure *Interfaces And Thin Films, Haibin Zhao
Optical Characterization Of Ferromagnetic Heterostructure *Interfaces And Thin Films, Haibin Zhao
Dissertations, Theses, and Masters Projects
This thesis presents optical characterizations of interfaces in ferromagnetic heterostructures and thin films used for spin polarized electronic devices. In these experiments, femtosecond laser spectroscopies are exploited to investigate the interface magnetization reversal, spin precession, and band offset, which are crucial in determining the performances of spintronic devices.;First, magnetization-induced second-harmonic-generation (MSHG) is applied to study interface magnetism in a hybrid structure containing a noncentrosymmetric semiconductor---Fe/AlGaAs. The reversal process of Fe interface layer magnetization is compared with the bulk magnetization reversal. In Fe/AlGaAs (001), the interface magnetization is found to be decoupled from the bulk magnetization based on the different switching …
Internal Magnetic Field Distribution Of A Type Ii High Tc Superconductor With Non-Conducting Inclusions, Yuxin Dai
Dissertations, Theses, and Masters Projects
The internal magnetic field distributions for a type II superconductor (a single crystal YBa2Cu3O7-delta ) with large normal inclusions (YBa2Cu3O 7-delta) are studied. A model based on the London Equations has been successfully developed and applied to the interpretation of the pSR data on this system. In our model, these inclusions are assumed to be cylindrical in shape and infinite in length. Therefore, this model should be especially appropriate for the prediction of field distributions in single crystal superconductors in which columnar defects have been purposely introduced to enhance pinning.;muSR experiments on a large single-crystal sample of YBa2C u3O7-delta with …
Static And Ultrafast Moke Studies Of Exchange -Biased Cobalt Systems, Keoki A. Seu
Static And Ultrafast Moke Studies Of Exchange -Biased Cobalt Systems, Keoki A. Seu
Dissertations, Theses, and Masters Projects
We have studied the exchange bias interaction in metal bilayers IrMn/Co and FeMn/Co using the static and ultrafast pump-probe Kerr effects. Experiments conducted on wedged Co samples show that the exchange bias interaction is sensitive to the buffer layers grown beneath it when the antiferromagnetic layer is FeMn. The exchange bias strength, as measured by the shift in the magnetic hysteresis loop, follows a 1/tFM dependence as reported in the literature. The time-domain pump-probe experiments reveal coherent magnetization oscillations, whose frequencies are comparable to those measured by frequency-domain FMR measurements, and they fit well to FMR equations for the frequency. …
The Effect Of Workload Dependence In Systems: Experimental Evaluation, Analytic Models, And Policy Development, Qi Zhang
Dissertations, Theses, and Masters Projects
This dissertation presents an analysis of performance effects of burstiness (formalized by the autocorrelation function) in multi-tiered systems via a 3-pronged approach, i.e., experimental measurements, analytic models, and policy development. This analysis considers (a) systems with finite buffers (e.g., systems with admission control that effectively operate as closed systems) and (b) systems with infinite buffers (i.e., systems that operate as open systems).;For multi-tiered systems with a finite buffer size, experimental measurements show that if autocorrelation exists in any of the tiers in a multi-tiered system, then autocorrelation propagates to all tiers of the system. The presence of autocorrelated flows in …
Physiological Consequences Of High Water Flow On The Coral Montastrea Annularis (Ellis And Solander, 1786), Lawrence W. Carpenter
Physiological Consequences Of High Water Flow On The Coral Montastrea Annularis (Ellis And Solander, 1786), Lawrence W. Carpenter
Dissertations, Theses, and Masters Projects
Water-flow is a vital component to the life histories of sessile marine invertebrates and essential to the structure and function of coral reefs. Recent studies have identified water-flow as an asset in the resistance to and recovery from short-term bleaching events of high irradiance and thermal increases. to determine whether the benefits of water-flow scale from the landscape level down to the flow patterns experienced over individual polyps and to quantify potential metabolic consequences, three studies were performed on Montastrea annularis (Ellis and Solander, 1786), using in situ heated bleaching flow-chambers during two saturation missions at the Aquarius underwater laboratory. …
Linking Land To Ocean: Flux And Fate Of Water And Sediment From The Yangtze River To The East China Sea, Kehui Xu
Dissertations, Theses, and Masters Projects
Although precipitation and runoff for the entire Yangtze River watershed have changed little since 1950, the increase of runoff in Yangtze southern sub-basin has been much larger than that of precipitation, reflecting decreased temperatures and evapotranspiration, In contrast, the marked decreases in runoff in northern Yangtze have been due mainly to increased water consumption. Since the 1980s, the Yangtze sediment load has declined dramatically, and 2004 loads at Yichang (just below the Three Gorges Dam - TGD) and Datong (lower stream) were only 12% and 33% of those in the 1950s and 60s, reflecting precipitation decline, landuse change, and most …
Time-Resolved Magneto-Optical Imaging Of Superconducting Ybco Thin Films In The High-Frequency Ac Current Regime, Alexander Frey
Time-Resolved Magneto-Optical Imaging Of Superconducting Ybco Thin Films In The High-Frequency Ac Current Regime, Alexander Frey
Dissertations, Theses, and Masters Projects
No abstract provided.
Disposition Of Wastewater-Associated Polybrominated Diphenyl Ethers In A Freshwater Receiving Stream, Mark Joseph La Guardia
Disposition Of Wastewater-Associated Polybrominated Diphenyl Ethers In A Freshwater Receiving Stream, Mark Joseph La Guardia
Dissertations, Theses, and Masters Projects
No abstract provided.
Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman
Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman
Dissertations, Theses, and Masters Projects
The Chesapeake Bay spawning stock of striped bass, Morone saxatilis, is considered one of the largest sources of juvenile production along the Atlantic coast and exhibits a high degree of interannual recruitment variability. Year class strength is judged by near-shore seine surveys that cover major tributaries of Chesapeake Bay and survey results are incorporated into annual stock assessments. In these surveys, the contribution of the Rappahannock River (Virginia) to total production is significant. In this system, abundance of juveniles is highest at a single seine site, suggesting that juvenile production may be related to habitat heterogeneity and food availability. To …
A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine
A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine
Dissertations, Theses, and Masters Projects
No abstract provided.
Passive Available Bandwidth: Applying Self -Induced Congestion Analysis Of Application-Generated Traffic, Marcia Zangrilli Bryan
Passive Available Bandwidth: Applying Self -Induced Congestion Analysis Of Application-Generated Traffic, Marcia Zangrilli Bryan
Dissertations, Theses, and Masters Projects
Monitoring end-to-end available bandwidth is critical in helping applications and users efficiently use network resources. Because the performance of distributed systems is intrinsically linked to the performance of the network, applications that have knowledge of the available bandwidth can adapt to changing network conditions and optimize their performance. A well-designed available bandwidth tool should be easily deployable and non-intrusive. While several tools have been created to actively measure the end-to-end available bandwidth of a network path, they require instrumentation at both ends of the path, and the traffic injected by these tools may affect the performance of other applications on …
Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke
Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke
Dissertations, Theses, and Masters Projects
The barndoor skate Dipturus laevis is one of seven species in the United States Northwest Atlantic skate complex. The species received little attention until a recent article published in Science reported that the barndoor skate might be on the brink of extinction. In this study, we address not only the virtual lack of information on the life history of the species, but also develop methodologies to assist in the assessment of the barndoor skate population. to investigate the life history of the species, data were collected from 2,310 specimens caught during commercial sea scallop dredging in the southern section of …
The Effects Of Climate Change On The Population Ecology Of The Atlantic Surf Clam, Spisula Solidissima, In The Middle Atlantic Bight, Adriana Picariello
The Effects Of Climate Change On The Population Ecology Of The Atlantic Surf Clam, Spisula Solidissima, In The Middle Atlantic Bight, Adriana Picariello
Dissertations, Theses, and Masters Projects
No abstract provided.
Uv Cure Kinetics Of Dimethacrylate Thin And Thick Samples, Yuemei Zhang
Uv Cure Kinetics Of Dimethacrylate Thin And Thick Samples, Yuemei Zhang
Dissertations, Theses, and Masters Projects
UV curing is using UV light as the energy source to induce the polymerization of liquid monomers and oligomers to form a solid polymer. Because UV polymerization is fast and energy-saving and a UV curable system has no VOC (volatile organic compound), this new technology has developed rapidly from thin film applications to thick sample applications. In addition, since the UV cure process can be controlled spatially and temporally, it also has an important application to make gradient materials with locally optimized properties. However, most research on UV cure is based on thin film applications, and the cure kinetics of …
Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston
Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston
Dissertations, Theses, and Masters Projects
No abstract provided.
Population Genetic Structure Of Escolar (Lepidocybium Flavobrunneum) And A Molecular Phylogeny Of The Trichiuroidea, Kirsten Brendtro
Population Genetic Structure Of Escolar (Lepidocybium Flavobrunneum) And A Molecular Phylogeny Of The Trichiuroidea, Kirsten Brendtro
Dissertations, Theses, and Masters Projects
No abstract provided.
Community Structure And Biogeography Of Mussel Bed Communities At Pacific Hydrothermal Vents: Lau And North Fiji Back-Arc Basins, 32° S---East Pacific Rise, And 38° S---Pacific Antarctic Ridge, Elizabeth Anne Blake
Community Structure And Biogeography Of Mussel Bed Communities At Pacific Hydrothermal Vents: Lau And North Fiji Back-Arc Basins, 32° S---East Pacific Rise, And 38° S---Pacific Antarctic Ridge, Elizabeth Anne Blake
Dissertations, Theses, and Masters Projects
No abstract provided.
The Influence Of Predation On The Nesting Ecology Of Diamondback Terrapins (Malaclemys Terrapin) In The Lower Chesapeake Bay, Victoria Ann Ruzicka
The Influence Of Predation On The Nesting Ecology Of Diamondback Terrapins (Malaclemys Terrapin) In The Lower Chesapeake Bay, Victoria Ann Ruzicka
Dissertations, Theses, and Masters Projects
No abstract provided.
Novel Derivatizing Agents For The Determination Of Methylmercury By Gas Chromatography Using Electron Capture Detection, Crystal Marie Irwin
Novel Derivatizing Agents For The Determination Of Methylmercury By Gas Chromatography Using Electron Capture Detection, Crystal Marie Irwin
Dissertations, Theses, and Masters Projects
No abstract provided.