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Full-Text Articles in Physical Sciences and Mathematics

The Primary Source Of Environmental Concern: New Environmental Paradigm Or Presumed Vested Interest Based On Area Of Residence?, Scott Christopher Ramsey Jan 1995

The Primary Source Of Environmental Concern: New Environmental Paradigm Or Presumed Vested Interest Based On Area Of Residence?, Scott Christopher Ramsey

Dissertations, Theses, and Masters Projects

No abstract provided.


Impact Of Artificial Reef Associates On Macrobenthic Community Structure In Florida Bay, Heinz Michael Proft Jan 1995

Impact Of Artificial Reef Associates On Macrobenthic Community Structure In Florida Bay, Heinz Michael Proft

Dissertations, Theses, and Masters Projects

No abstract provided.


Crassostrea Virginica On Constructed Intertidal Oyster Reefs: The Effects Of Tidal Height And Substrate Level On Settlement, Growth, And Mortality, Ian K. Bartol Jan 1995

Crassostrea Virginica On Constructed Intertidal Oyster Reefs: The Effects Of Tidal Height And Substrate Level On Settlement, Growth, And Mortality, Ian K. Bartol

Dissertations, Theses, and Masters Projects

No abstract provided.


Occurrence, Fate And Effects Of Polychlorinated Terphenyls In An Estuarine Environment, Kathryn Gallagher Jan 1995

Occurrence, Fate And Effects Of Polychlorinated Terphenyls In An Estuarine Environment, Kathryn Gallagher

Dissertations, Theses, and Masters Projects

Aroclor 5432, a mixture of polychlorinated terphenyls (PCT), was detected in sediment and several biological compartments including: saltmarsh cordgrass (Spartina alterniflora), American oysters (Crassostrea virginica), red-jointed fiddler crabs (Uca minax), wharf crabs (Sesarma reticulatum) and mummichogs (Fundulus heteroclitus) collected from Tabbs Creek. This tidal creek is located in the southern Chesapeake Bay region. Species from several phyla were selected in order to examine PCT accumulation in physiologically and ecologically different organisms. In general, PCT concentrations in sediment and biota decreased with distance downstream from the PCT outfall. The organism with the highest mean concentration (18,300 &\mu&g/kg dry weight) was the …


Beam Dynamics In The Cebaf Superconducting Cavities, Zenghai Li Jan 1995

Beam Dynamics In The Cebaf Superconducting Cavities, Zenghai Li

Dissertations, Theses, and Masters Projects

This work is a study of beam dynamics in the CEBAF superconducting cavities under the influence of the fields generated by externally applied RF and beam particles.;A full 3-D modeling of the CEBAF 5-cell superconducting cavity is carried out. Details of the modeling with MAFIA are discussed. Multipole fields due to the asymmetric couplers are studied by means of 3-D Fourier transforms. The cavity steering and focusing of the multipole fields are studied. Experimental measurements of these effects are performed to validate the modeling. Evaluation of the cavity misalignment is discussed. The emittance degradation effects in the CEBAF superconducting linacs …


A Comparison Of Three Wetland Evaluation Methods In Their Assessment Of Nontidal Wetlands In The Coastal Plain Of Virginia, Melissa Claire Chaun Jan 1995

A Comparison Of Three Wetland Evaluation Methods In Their Assessment Of Nontidal Wetlands In The Coastal Plain Of Virginia, Melissa Claire Chaun

Dissertations, Theses, and Masters Projects

No abstract provided.


Resuspension Behavior Of Natural Estuarine Sediments, Chang-Hee Lee Jan 1995

Resuspension Behavior Of Natural Estuarine Sediments, Chang-Hee Lee

Dissertations, Theses, and Masters Projects

The resuspension behavior of natural estuarine sediments was studied using the VIMS Sea Carousel, a benthic annular flume. The bed shear stresses produced by the flume were measured by a hot-film sensor mounted flush on the bottom of a laboratory version of the Carousel under a clear-water and flat-bottom condition. Measurements showed a reasonably uniform bed shear stress across the channel and agreed with the relationship &\tau\sb{lcub}\rm b{rcub}=0.011\Omega\sp{lcub}1.69{rcub},& where &\Omega& = ring speed (rpm) and &\tau\sb{lcub}\rm b{rcub}& = spatially-averaged bed shear stress (N/m&\sp2&), predicted from a previous numerical study. Thus, the &\tau\sb{lcub}\rm b{rcub}& was used as a bed shear stress …


Reproductive And Feeding Biology Of Selected Syngnathids (Pisces: Teleostei) Of The Western Atlantic, Rogerio Luiz Teixeira Jan 1995

Reproductive And Feeding Biology Of Selected Syngnathids (Pisces: Teleostei) Of The Western Atlantic, Rogerio Luiz Teixeira

Dissertations, Theses, and Masters Projects

The reproductive and feeding biology of five syngnathid species of the western Atlantic were studied: the pipefishes Syngnathus fuscus, S. floridae, the lined seahorse Hippocampus erectus of Chesapeake Bay; and the pipefishes S. folletti and Oostethus lineatus, from southern and southeast Brazil, respectively. Male syngnathids incubate eggs received from females in a ventral brood pouch, females do not play any additional role in parental care after mating. This natural sex role reversal is a unique characteristic that all male syngnathids have. In other fishes, parental care is usually a female prerogative. Most pipefishes are polygamous, while seahorses are monogamous. Syngnathus …


A Study Of The Histozoic Oyster Parasite, Perkinsus Marinus: I. Disease Processes In American Oysters (Crassostrea Virginica). Ii. Biochemistry Of Perkinsus Marinus, Aswani K. Volety Jan 1995

A Study Of The Histozoic Oyster Parasite, Perkinsus Marinus: I. Disease Processes In American Oysters (Crassostrea Virginica). Ii. Biochemistry Of Perkinsus Marinus, Aswani K. Volety

Dissertations, Theses, and Masters Projects

Numerous studies have investigated the disease processes of Perkinsus marinus in the oyster, Crassostrea virginica. However, the transmission dynamics and factors affecting P. marinus infection are still unclear. The objectives of this study were to investigate: (1) the principal and most effective lifestage of P. marinus, (2) the synergistic effects of temperature, salinity and P. marinus dose on disease prevalence, (3) suppression of host reactive oxygen intermediates by P. marinus, (4) the localization of acid phosphatase in the parasite, (5) the effects of temperature and salinity on acid phosphatase secretion, and (6) the P. marinus lipid and fatty acid composition. …


Movements And Ecology Of Summer Flounder, Paralichthys Dentatus, Tagged In The Southern Mid-Atlantic Bight, Joseph C. Desfosse Jan 1995

Movements And Ecology Of Summer Flounder, Paralichthys Dentatus, Tagged In The Southern Mid-Atlantic Bight, Joseph C. Desfosse

Dissertations, Theses, and Masters Projects

A total of 12,323 summer flounder were tagged and released in Chesapeake Bay, the coastal waters off Virginia Beach, and the Eastern Shore during 1987-89. Excluding immediate recaptures, a total of 675 were recaptured for an overall return rate of 5.5%. Returns from the commercial fishery (56.2%) outnumbered those from the recreational fishery (35.7%). The majority of returns (47.1%) came from either Virginia waters or areas to the south, while only 12.8% were from areas to the north of Virginia. offshore returns accounted for 8.5% of the total. Returns with insufficient location data made up the remaining 31.5%. of the …


Blends Of Reactive Diluents With Phenylethynyl-Terminated Arylene Ether Oligomers, Rachel Louise Knudsen Jan 1995

Blends Of Reactive Diluents With Phenylethynyl-Terminated Arylene Ether Oligomers, Rachel Louise Knudsen

Dissertations, Theses, and Masters Projects

No abstract provided.


Immigration Variability And Post-Settlement Processes Of The Spiny Lobster, Panulirus Argus, In The Exuma Cays, Bahamas, Luis Coba-Cetina Jan 1995

Immigration Variability And Post-Settlement Processes Of The Spiny Lobster, Panulirus Argus, In The Exuma Cays, Bahamas, Luis Coba-Cetina

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effects Of Underlying Geology On The Equilibrium Profile: A Case Study Off Duck, North Carolina, Patricia L. Tiedeman Jan 1995

The Effects Of Underlying Geology On The Equilibrium Profile: A Case Study Off Duck, North Carolina, Patricia L. Tiedeman

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Sunlight And Seasonal Temperature On Persistence Of Four Bacteriophages In An Estuarine Environment, Terri A. Muller Jan 1995

Effects Of Sunlight And Seasonal Temperature On Persistence Of Four Bacteriophages In An Estuarine Environment, Terri A. Muller

Dissertations, Theses, and Masters Projects

No abstract provided.


Metallization Of Polyimide Films To Enhance Dimensional Stability And To Achieve Reflective And Conductive Surfaces, David Scott Thompson Jan 1995

Metallization Of Polyimide Films To Enhance Dimensional Stability And To Achieve Reflective And Conductive Surfaces, David Scott Thompson

Dissertations, Theses, and Masters Projects

No abstract provided.


Studies On Processes Controlling The Input Of Agricultural Chemicals In Groundwater To Surface Waters, Edward Laurence Libelo Jan 1995

Studies On Processes Controlling The Input Of Agricultural Chemicals In Groundwater To Surface Waters, Edward Laurence Libelo

Dissertations, Theses, and Masters Projects

This dissertation describes several studies of groundwater quality, the fate and transport of nutrients and atrazine in groundwater systems and physical processes at the sediment-water interface which impact on groundwater discharge. Groundwater monitoring wells were installed at the Goodwins Island and Catlett Island NERRS sites in Virginia and agricultural, suburban and forest land use sites in the York and James River Basins. Groundwater was analyzed for nutrients, pH, salinity and trace organics. Shoreline land use, associated nutrient loading and an estimate of total groundwater flux suggest that groundwater contributes up to 30% of the total nitrogen input to the Chesapeake …


Effects Of Simulated Sediment Resuspension Events On The Abundance Of Water Column Bacteria Of Tomales Bay, California, Christopher J. Collumb Jan 1995

Effects Of Simulated Sediment Resuspension Events On The Abundance Of Water Column Bacteria Of Tomales Bay, California, Christopher J. Collumb

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effects Of Hook Type On The Hooking Mortality Of Two Size Classes Of Summer Flounder, Paralichthys Dentatus, Tracy D. Holton Jan 1995

The Effects Of Hook Type On The Hooking Mortality Of Two Size Classes Of Summer Flounder, Paralichthys Dentatus, Tracy D. Holton

Dissertations, Theses, and Masters Projects

No abstract provided.


A Numerical Model Of The Global Carbon Cycle To Predict Atmospheric Carbon Dioxide Concentrations, Alexis Demitrios Kambis Jan 1995

A Numerical Model Of The Global Carbon Cycle To Predict Atmospheric Carbon Dioxide Concentrations, Alexis Demitrios Kambis

Dissertations, Theses, and Masters Projects

A numerical model of the global carbon cycle is presented which includes the effects of anthropogenic &CO\sb2& emissions &(CO\sb2& produced from fossil fuel combustion, biomass burning, and deforestation) on the global carbon cycle. The model is validated against measured atmospheric &CO\sb2& concentrations. Future levels of atmospheric &CO\sb2& are then predicted for the following scenarios: (1) Business as Usual (BaU) for the period 1990-2000; (2) Same as (1), but with no biomass burning; (3) Same as (1), but with no fossil fuel combustion; (4) Same as (1), but with a doubled atmospheric &CO\sb2& concentration and a 2 K warmer surface temperature …


The Selective Synthesis Of 3-Alkylidenetetrahydrofurans, Robin Elaine Southward Jan 1995

The Selective Synthesis Of 3-Alkylidenetetrahydrofurans, Robin Elaine Southward

Dissertations, Theses, and Masters Projects

No abstract provided.


Constrained Least-Squares Digital Image Restoration, Rajeeb Hazra Jan 1995

Constrained Least-Squares Digital Image Restoration, Rajeeb Hazra

Dissertations, Theses, and Masters Projects

The design of a digital image restoration filter must address four concerns: the completeness of the underlying imaging system model, the validity of the restoration metric used to derive the filter, the computational efficiency of the algorithm for computing the filter values and the ability to apply the filter in the spatial domain. Consistent with these four concerns, this dissertation presents a constrained least-squares (CLS) restoration filter for digital image restoration. The CLS restoration filter is based on a comprehensive, continuous-input/discrete- processing/continuous-output (c/d/c) imaging system model that accounts for acquisition blur, spatial sampling, additive noise and imperfect image reconstruction. The …


Spawning And Ecology Of Early Life Stages Of Black Drum, Pogonias Cormis, In Lower Chesapeake Bay, Louis Broaddus Daniel Iii Jan 1995

Spawning And Ecology Of Early Life Stages Of Black Drum, Pogonias Cormis, In Lower Chesapeake Bay, Louis Broaddus Daniel Iii

Dissertations, Theses, and Masters Projects

During spring 1990 and 1991, ichthyoplankton surveys were conducted in lower Chesapeake Bay to estimate seasonal egg production, population biomass and the impact of predation by gelatinous zooplankton on early life stages of black drum, Pogonias cromis. Rearing experiments indicated that at least three species of sciaenid (silver perch, Bairdiella chrysoura; weakfish, Cynoscion regalis and P. cromis) were spawning in the survey area during both years. Specific identification of eggs based on previously published ranges of outside egg diameter (OED) were not reliable due to considerable overlap in diameter distributions. Analysis of weekly OED frequency revealed the presence of three …


Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik Jan 1995

Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik

Dissertations, Theses, and Masters Projects

There has been a growing interest in the commercial aquaculture of striped bass, Morone saxatilis. Little is known, however, about the nutritional requirements and feeding physiology of striped bass larvae. The objectives of this study were (a) to evaluate the efficiency of the live food enrichment techniques in studying the nutritional requirements for polyunsaturated fatty acids (PUFA), phospholipids and free amino acids, (b) to determine the ontogenetic changes of lipolytic enzymes, and (c) to develop a microencapsulated diet for striped bass larvae as full or partial replacement of live food. Three enrichment techniques, namely, microencapsulated fish oil, yeast/fish oil emulsion …


The Geomorphology And Shallow Structure Of The Northeastern New Jersey Continental Slope, Nicole D. Scott Jan 1995

The Geomorphology And Shallow Structure Of The Northeastern New Jersey Continental Slope, Nicole D. Scott

Dissertations, Theses, and Masters Projects

No abstract provided.


Filtration Of Oysters In Patches: Effects Of Water Flow And Seston Composition, Deborah Armitage Harsh Jan 1995

Filtration Of Oysters In Patches: Effects Of Water Flow And Seston Composition, Deborah Armitage Harsh

Dissertations, Theses, and Masters Projects

No abstract provided.


High-Resolution Seismic Stratigraphy Of The Ganges-Brahmaputra River System: Subaqueous Deltaic Progradation On The Bengal Shelf, Beth Michele Levy Jan 1995

High-Resolution Seismic Stratigraphy Of The Ganges-Brahmaputra River System: Subaqueous Deltaic Progradation On The Bengal Shelf, Beth Michele Levy

Dissertations, Theses, and Masters Projects

No abstract provided.


Osmotic Tolerance And Volume Regulation In Cultured Cells Of The Oyster Pathogen Perkinsus Marinus, Caroline L. O'Farrell Jan 1995

Osmotic Tolerance And Volume Regulation In Cultured Cells Of The Oyster Pathogen Perkinsus Marinus, Caroline L. O'Farrell

Dissertations, Theses, and Masters Projects

No abstract provided.


Wave Diffraction And Refraction Problem And A Block-Wise Band Matrix Solver, Changqing Li Jan 1995

Wave Diffraction And Refraction Problem And A Block-Wise Band Matrix Solver, Changqing Li

Dissertations, Theses, and Masters Projects

No abstract provided.


An Electronic Storage And Access System For Special Education Legislation, Courtney Siler Frantz Jan 1995

An Electronic Storage And Access System For Special Education Legislation, Courtney Siler Frantz

Dissertations, Theses, and Masters Projects

In the field of education, instructional leaders must know the regulations governing the assessment, curriculum, and instruction of all students. An area of special concern is the regulations governing programs for students with disabilities. Although the average population of students with disabilities may represent less than 10% of the total student body, the school administrator is responsible for maintaining access to the most current regulations, for accurately interpreting, and effectively implementing federal and state mandates to ensure that the due process rights of the students with disabilities are upheld. Yet the laws and regulations governing special education programs are continually …


Continuous Electron Stimulated Oxygen Atom Emission From Ag Permeation Membranes, Gilda Ann Newton Miner Jan 1995

Continuous Electron Stimulated Oxygen Atom Emission From Ag Permeation Membranes, Gilda Ann Newton Miner

Dissertations, Theses, and Masters Projects

No abstract provided.