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Full-Text Articles in Physical Sciences and Mathematics

A Structural Factoring Approach For Analyzing Probabilistic Networks, Kelly J. Hayhurst Jan 1989

A Structural Factoring Approach For Analyzing Probabilistic Networks, Kelly J. Hayhurst

Dissertations, Theses, and Masters Projects

No abstract provided.


Carbon, Nitrogen, And Phosphorus Discharge From The Altamaha River, Georgia, Frederick A. Hoffman Jan 1989

Carbon, Nitrogen, And Phosphorus Discharge From The Altamaha River, Georgia, Frederick A. Hoffman

Dissertations, Theses, and Masters Projects

No abstract provided.


Meristic And Morphometric Comparison Of Three Juvenile Alosa Species: Blueback Herring, A Aestivalis; Alewife, A Pseudoharengus; And American Shad, A Sapidissima, Joseph C. Desfosse Jan 1989

Meristic And Morphometric Comparison Of Three Juvenile Alosa Species: Blueback Herring, A Aestivalis; Alewife, A Pseudoharengus; And American Shad, A Sapidissima, Joseph C. Desfosse

Dissertations, Theses, and Masters Projects

No abstract provided.


Dielectric And Kinetic Analysis Of Thermosetting Polyester Resin, Patricia Haverty Tully Jan 1989

Dielectric And Kinetic Analysis Of Thermosetting Polyester Resin, Patricia Haverty Tully

Dissertations, Theses, and Masters Projects

No abstract provided.


Recruitment And Growth Of Juvenile Crassostrea Virginica (Gmelin) In Relation To Tidal Zonation, George Curtis Roegner Jan 1989

Recruitment And Growth Of Juvenile Crassostrea Virginica (Gmelin) In Relation To Tidal Zonation, George Curtis Roegner

Dissertations, Theses, and Masters Projects

No abstract provided.


Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman Jan 1989

Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman

Dissertations, Theses, and Masters Projects

No abstract provided.


Palatability Of Freshwater Surface Hemiptera To Potential Fish Predators (Lepomis Macrochirus And Gambusia Affinis), Julie Heyward Mounts Jan 1989

Palatability Of Freshwater Surface Hemiptera To Potential Fish Predators (Lepomis Macrochirus And Gambusia Affinis), Julie Heyward Mounts

Dissertations, Theses, and Masters Projects

No abstract provided.


Non-Lattice Monte Carlo Simulations Of Polymer Motion, David Albert Eichinger Jan 1989

Non-Lattice Monte Carlo Simulations Of Polymer Motion, David Albert Eichinger

Dissertations, Theses, and Masters Projects

No abstract provided.


Virginia's Pelagic Recreational Fishery: Biological, Socioeconomic And Fishery Components, Eleanor A. Bochenek Jan 1989

Virginia's Pelagic Recreational Fishery: Biological, Socioeconomic And Fishery Components, Eleanor A. Bochenek

Dissertations, Theses, and Masters Projects

Catch, effort, fleet size and boat owner expenditure data were collected on Virginia's recreational marlin/tuna fishery for the 1983-1985 seasons. Logbooks, dockside interviews and a telephone survey were evaluated to determine which method was the most efficient and effective for collecting and estimating catch and effort for Virginia's pelagic recreational fishery. In 1984, logbooks were used to collect catch and effort data and fishing effort was estimated using Bochenek's method. Very few fishermen returned their logbooks and as a result this data is probably less reliable than the data collected in other years. Due to the poor return of logbooks, …


Pcb Congener Analysis With Hall Electrolytic Conductivity Detection, Robert D. Edstrom Jan 1989

Pcb Congener Analysis With Hall Electrolytic Conductivity Detection, Robert D. Edstrom

Dissertations, Theses, and Masters Projects

This work reports the development of an analytical methodology for the analysis of PCB congeners based on integrating relative retention data provided by other researchers. The retention data were transposed into a multiple retention marker system which provided good precision in the calculation of relative retention indices for PCB congener analysis. Analytical run times for the developed methodology were approximately one hour using a commercially available GC capillary column. A Tracor Model 700A Hall Electrolytic Conductivity Detector (HECD) was employed in the GC detection of Aroclor standards and environmental samples. Responses by the HECD provided good sensitivity and were reasonably …


Uptake Kinetics And Toxicity Of Diazinon In The American Oyster, Crassostrea Virginica Gmelin, Ruth L. Williams Jan 1989

Uptake Kinetics And Toxicity Of Diazinon In The American Oyster, Crassostrea Virginica Gmelin, Ruth L. Williams

Dissertations, Theses, and Masters Projects

Several aspects of effects of the organophosphate pesticide diazinon on the American oyster Crassostrea virginica Gmelin were investigated. Uptake of diazinon directly from water was compared with uptake of diazinon sorbed to either fine sediment or algae; the primary route of assimilation seems to be from the water. Concentrations of diazinon between 0.91 and 2.03 mg/L inhibit shell growth during 96 hours of exposure; there is a sharp threshold of effect for this response which is probably an indirect one caused by lack of food during shell closure. Acetylcholinesterase inhibition is significant in oyster heart tissue at concentrations of approximately …


The Influence Of Tributyltin On Various Aspects Of Activation And Reactive Oxygen Formation In Oyster Toadfish (Opsanus Tau) Macrophages, Charles D. Rice Jan 1989

The Influence Of Tributyltin On Various Aspects Of Activation And Reactive Oxygen Formation In Oyster Toadfish (Opsanus Tau) Macrophages, Charles D. Rice

Dissertations, Theses, and Masters Projects

The effects of tributyltin (TBT) on phorbol myristate acetate (PMA)- and calcium ionophore (A23187)-stimulated peritoneal macrophages from oyster toadfish (Opsanus tau) were evaluated in a luminol-dependent chemiluminescence (CL) assay. PMA-stimulated CL responses were increased by in vitro exposure to 50 ug/L TBT, but depressed to baseline values by 500 ug/L TBT. A23187-stimulated CL increased with 5 ug/L and 50 ug/L TBT, and depressed by 500 ug/L TBT. Responses stimulated by synergistic doses of PMA and A23187 were increased by 50 ug/L TBT and depressed by 500 ug/L TBT. Enhanced PMA- and A23187-stimulated CL following TBT exposure returned to baseline values …


Subsurface Hydrodynamics And Nutrient Exchange Within An Extensive Tidal Freshwater Wetland, William G. Reay Jan 1989

Subsurface Hydrodynamics And Nutrient Exchange Within An Extensive Tidal Freshwater Wetland, William G. Reay

Dissertations, Theses, and Masters Projects

Located between upland and riverine systems, extensive tidal freshwater wetlands are influenced by a variety of recharging water sources and their respective nutrient contents. Conversely, tidal wetlands discharge interstitial waters and solutes to surface waters during periods of aerial exposure. Geohydrologic and model simulation methodology were utilized in order to aid in the understanding of wetland subsurface flow dynamics, its influence upon pore water nutrient chemistry, and its role in nutrient exchange with adjacent surface waters. Interstitial water nutrient chemistry was monitored along three transects extending from the uplands to the creekbank edge. Surface waters were also monitored throughout the …


Distribution Analysis Of Heavy Minerals On The Inner Continental Shelf Of Virginia, Hakan Ozalpasan Jan 1989

Distribution Analysis Of Heavy Minerals On The Inner Continental Shelf Of Virginia, Hakan Ozalpasan

Dissertations, Theses, and Masters Projects

No abstract provided.


Hypoxic Water Transport By Sub-Tidal Circulation From Chesapeake Bay To The Lower Rappahannock Estuary, Ned Burger Jan 1989

Hypoxic Water Transport By Sub-Tidal Circulation From Chesapeake Bay To The Lower Rappahannock Estuary, Ned Burger

Dissertations, Theses, and Masters Projects

No abstract provided.


Effect Of Nitrogen And Phosphorus Enrichment On Lipid And Fatty Acid Composition Of Estuarine Microplankton, Jia Chen Jan 1989

Effect Of Nitrogen And Phosphorus Enrichment On Lipid And Fatty Acid Composition Of Estuarine Microplankton, Jia Chen

Dissertations, Theses, and Masters Projects

No abstract provided.


Effect Of Water Column Ph And No3 On Ortho-Phosphate Release Rates From Freshwater Sediments, Beverly Eloise Baker Jan 1989

Effect Of Water Column Ph And No3 On Ortho-Phosphate Release Rates From Freshwater Sediments, Beverly Eloise Baker

Dissertations, Theses, and Masters Projects

No abstract provided.


The Influence Of Salinity On The Swimming Behavior Of Larval Crassostrea Virginica (Gmelin), Kevin J. Mccarthy Jan 1989

The Influence Of Salinity On The Swimming Behavior Of Larval Crassostrea Virginica (Gmelin), Kevin J. Mccarthy

Dissertations, Theses, and Masters Projects

No abstract provided.


A Measurement Of The Decay Rate For The Process Kaon(L) Going To Positive Muon Negative Muon, Christopher John Kenney Jan 1989

A Measurement Of The Decay Rate For The Process Kaon(L) Going To Positive Muon Negative Muon, Christopher John Kenney

Dissertations, Theses, and Masters Projects

A sample of 87 events of the GIM suppressed decay K$\sb{\rm L} \to \mu\sp+\mu\sp-$ were observed in an experiment performed in 1988 at the Brookhaven National Laboratory. Concurrently, 8,887 examples of the CP-violating decay K$\sb{\rm L} \to \pi\sp+\pi\sp-$ were also seen. The apparatus consisted of a double-magnet spectrometer as well as electromagnetic and muon detector systems. From the previously measured branching ratio for K$\sb{\rm L} \to \pi\sp+\pi\sp-$ and the different instrumental acceptances of the detector for the two decays, the data sample was normalized to the effective number of K$\sb{\rm L}$ decays observed. A value for the ratio (K$\sb{\rm L} …


Utilization Of A Helium Discharge Detector For Quantitation Of Organohalogen Compounds, David Andrew Ryan Jan 1989

Utilization Of A Helium Discharge Detector For Quantitation Of Organohalogen Compounds, David Andrew Ryan

Dissertations, Theses, and Masters Projects

No abstract provided.


Ordering Events In A Distributed System: A Performance Evaluation, Jeffrey E. Payne Jan 1989

Ordering Events In A Distributed System: A Performance Evaluation, Jeffrey E. Payne

Dissertations, Theses, and Masters Projects

No abstract provided.


Interactive Simulations For Knowledge Acquisition, Sorel Bosan Jan 1989

Interactive Simulations For Knowledge Acquisition, Sorel Bosan

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Selected Nitrogen-Containing Aromatic Compounds (Ncacs) On Physiological Properties In Escherichia Coli, W. James Catallo Iii Jan 1989

Effects Of Selected Nitrogen-Containing Aromatic Compounds (Ncacs) On Physiological Properties In Escherichia Coli, W. James Catallo Iii

Dissertations, Theses, and Masters Projects

This research examined the effects of quinoline and 4-azafluorene on respiratory electron transport rate (ET), outer membrane permeability and topology, oxygen consumption, and viable cell density in Escherichia coli cell suspensions. ET was estimated spectrophotometrically using INT (2-(p-iodophenyl)-3-(p-nitrophenyl)-5-(phenyl)-2H-tetrazolium chloride, which is reduced in vivo to a red colored formazan (INTF). Both test compounds caused anomalous dose-response behavior in INT assays: in a defined window of doses, ET rates near or above the controls were observed. These doses showed altered INT reduction kinetics, decreased cellular oxygen demand, and decreased viable cell densities. Experiments with E. coli spheroplast preparations, gram(+) cells, and …


Adaptation Of Lr Parsing To Production System Interpretation, Louis Paul Slothouber Jan 1989

Adaptation Of Lr Parsing To Production System Interpretation, Louis Paul Slothouber

Dissertations, Theses, and Masters Projects

This thesis presents such a new production system architecture, called a palimpsest parser, that adapts LR parsing technology to the process of controlled production system interpretation. Two unique characteristics of this architecture facilitate the construction and execution of large production systems: the rate at which productions fire is independent of production system size, and the modularity inherent in production systems is preserved and enhanced. In addition, individual productions may be evaluated in either a forward or backward direction, production systems can be integrated with other production systems and procedural programs, and production system modules can be compiled into libraries and …


Nmr On Single Crystals Of Potassium Cyanogen Bromide (A Measurement Of The Orientational Probability Distribution Function Of The Negatively Charged Cyanogen Ion), Jeffrey Howard Walton Jan 1989

Nmr On Single Crystals Of Potassium Cyanogen Bromide (A Measurement Of The Orientational Probability Distribution Function Of The Negatively Charged Cyanogen Ion), Jeffrey Howard Walton

Dissertations, Theses, and Masters Projects

Single crystals of K(CN)$\sb{\rm x}$/(Br)$\sb{\rm 1-x}$ enriched in $\sp{15}$N have been studied by $\sp{15}$N NMR. Because of the anisotropic chemical shift, the NMR frequency spectrum of the orientational glass state reflects the distribution of cyanide orientations. By studying the spectrum at many orientations of each crystal, the orientational probability distribution function P($\Omega$) has been determined for x = 0.50 and for x = 0.20. The probability function is largest along the (100) directions, intermediate in the (110) directions, and nearly 0 along the (111) directions. The NMR determined P($\Omega$) is presented graphically and in terms of the Kubic Harmonic functions. …


Dielectric Monitoring Of Environmental Effects On The Cure Of Epoxy-Polyamide Coatings, Thomas Hamilton Jan 1989

Dielectric Monitoring Of Environmental Effects On The Cure Of Epoxy-Polyamide Coatings, Thomas Hamilton

Dissertations, Theses, and Masters Projects

No abstract provided.


Synthesis And Characterization Of 3-Alkylidenetetrahydrofurans, Kevin Patrick Dockery Jan 1989

Synthesis And Characterization Of 3-Alkylidenetetrahydrofurans, Kevin Patrick Dockery

Dissertations, Theses, and Masters Projects

No abstract provided.


A Kinetic Study Of The Oxidative Addition Of Simple Alkylvinyl Triflates To Tetrakis (Triphenylphosphine) Platinum(O), C. P. Desmond Longford Jan 1989

A Kinetic Study Of The Oxidative Addition Of Simple Alkylvinyl Triflates To Tetrakis (Triphenylphosphine) Platinum(O), C. P. Desmond Longford

Dissertations, Theses, and Masters Projects

No abstract provided.


Bottom Sediment Mobility At The Wolf Trap Site In The Lower Chesapeake Bay, Mary Mckean Howard-Strobel Jan 1989

Bottom Sediment Mobility At The Wolf Trap Site In The Lower Chesapeake Bay, Mary Mckean Howard-Strobel

Dissertations, Theses, and Masters Projects

No abstract provided.


Cannibalism Experiments With The Blue Crab (Callinectes Sapidus Rathbun): Potential Effects Of Size And Abundance, Christopher A. Peery Jan 1989

Cannibalism Experiments With The Blue Crab (Callinectes Sapidus Rathbun): Potential Effects Of Size And Abundance, Christopher A. Peery

Dissertations, Theses, and Masters Projects

No abstract provided.