Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 23 of 23
Full-Text Articles in Entire DC Network
Cell-Cell Interactions In The Development Of The Vascular System Of Xenopus, Krista Marie Stimson
Cell-Cell Interactions In The Development Of The Vascular System Of Xenopus, Krista Marie Stimson
Dissertations, Theses, and Masters Projects
No abstract provided.
Ethanol Preference In Peromyscus: An Association With Compromised Ethanol Metabolism, James Scott Lowman
Ethanol Preference In Peromyscus: An Association With Compromised Ethanol Metabolism, James Scott Lowman
Dissertations, Theses, and Masters Projects
No abstract provided.
The Effects Of Increased Inundation And Wrack Deposition On Photosynthesis And Respiration In A Virginia Salt Marsh, W. David Miller
The Effects Of Increased Inundation And Wrack Deposition On Photosynthesis And Respiration In A Virginia Salt Marsh, W. David Miller
Dissertations, Theses, and Masters Projects
No abstract provided.
Physical Parameters Affecting Incubating Temperatures In Loggerhead Sea Turtles, Caretta Caretta, In Virginia, William Mason Jones
Physical Parameters Affecting Incubating Temperatures In Loggerhead Sea Turtles, Caretta Caretta, In Virginia, William Mason Jones
Dissertations, Theses, and Masters Projects
Detailed physical profile of eight transplanted loggerhead sea turtle, Caretta caretta, nests were obtained from Virginia and northeastern North Carolina and reburied in Back Bay National Wildlife Refuge (BBNWR), Virginia Beach, Virginia during the summers of 1987, '88, and '89 to determine if the physical location of the egg within the nest had an affect on sex determination. Transplanted nests were reburied in sandy substrate at a depth of 15-60 em on south facing dunes, and a Campbell Scientific data-logger logged synchronously environmental data. The following data were collected: temperatures at various locations within a nest, net absorbed radiation, ambient …
The Phylogeny Of Coleoid Cephalopods Inferred From Molecular Evolutionary Analyses Of The Cytochrome C Oxidase I, Muscle Actin, And Cytoplasmic Actin Genes, David Bruno Carlini
The Phylogeny Of Coleoid Cephalopods Inferred From Molecular Evolutionary Analyses Of The Cytochrome C Oxidase I, Muscle Actin, And Cytoplasmic Actin Genes, David Bruno Carlini
Dissertations, Theses, and Masters Projects
Although the fossil record of early cephalopods is rich and demonstrates the dominance of the group in Paleozoic times, the mainly soft-bodied coleoids (Cephalopoda: Coleoidea) are poorly represented. Therefore, little is known of the evolutionary history of coleoids through paleontology and current classifications of the subclass are based primarily on the morphology of extant representatives. A molecular phylogenetic analysis of the Coleoidea was therefore warranted. Phylogenetic relationships within the Coleoidea were constructed using molecular sequence data from one mitochondrial and two nuclear genes: cytochrome c oxidase I (COI) and two unlinked actin genes (Actin I and Actin II, respectively). A …
Development And Analysis Of A Nutrient Trading Program For The James River Watershed, Jennifer M. Reid
Development And Analysis Of A Nutrient Trading Program For The James River Watershed, Jennifer M. Reid
Dissertations, Theses, and Masters Projects
No abstract provided.
Tagging And Habitat Utilization Of Juvenile Summer Flounder, Paralichthys Dentatus, Richard Thomas Kraus
Tagging And Habitat Utilization Of Juvenile Summer Flounder, Paralichthys Dentatus, Richard Thomas Kraus
Dissertations, Theses, and Masters Projects
No abstract provided.
The Parasite Fauna Of The Wreckfish, Polyprion Americanus, In The North Atlantic Ocean: Application To Host Biology And Stock Identification, Colleen Jill Fennessy
The Parasite Fauna Of The Wreckfish, Polyprion Americanus, In The North Atlantic Ocean: Application To Host Biology And Stock Identification, Colleen Jill Fennessy
Dissertations, Theses, and Masters Projects
No abstract provided.
Determination Of Trace Levels Of Lead In Whole Blood By Graphite Furnace Atomic Absorption Spectroscopy, Leslie A. Sombers
Determination Of Trace Levels Of Lead In Whole Blood By Graphite Furnace Atomic Absorption Spectroscopy, Leslie A. Sombers
Dissertations, Theses, and Masters Projects
No abstract provided.
Ecosystem Analysis Of Water Column Processes In The York River Estuary, Virginia: Historical Records, Field Studies And Modeling Analysis, Yongsik Sin
Dissertations, Theses, and Masters Projects
Analyses of EPA long-term datasets (1985--1994) combined with field studies and ecosystem model development were used to investigate phytoplankton and nutrient dynamics in the York River estuary. Analysis of the EPA dataset showed that algal blooms occurred during winter-spring followed by smaller summer blooms. Peak phytoplankton biomass during the winter-spring blooms occurred in the mid reach of the mesohaline zone whereas during the summer bloom it occurred in the tidal fresh-mesolialine transition zone. River discharge appears to be the major factor controlling the location and timing of the winter-spring blooms and the relative degree of potential nitrogen (N) and phosphorus …
Early Secondary Succession In The Bottomland Hardwood Forests Of Southeastern Virginia, David Randolph Spencer
Early Secondary Succession In The Bottomland Hardwood Forests Of Southeastern Virginia, David Randolph Spencer
Dissertations, Theses, and Masters Projects
No abstract provided.
Does Plant Diversity Control Animal Diversity?: An Experimental Approach, John Daniel Parker
Does Plant Diversity Control Animal Diversity?: An Experimental Approach, John Daniel Parker
Dissertations, Theses, and Masters Projects
No abstract provided.
Oyster Reef Broodstock Enhancement In The Great Wicomico River, Virginia, Melissa Southworth
Oyster Reef Broodstock Enhancement In The Great Wicomico River, Virginia, Melissa Southworth
Dissertations, Theses, and Masters Projects
No abstract provided.
Tidal Freshwater And Oligohaline Benthos: Evaluating The Development Of A Benthic Index Of Biological Integrity For Chesapeake Bay, Robyn C. Draheim
Tidal Freshwater And Oligohaline Benthos: Evaluating The Development Of A Benthic Index Of Biological Integrity For Chesapeake Bay, Robyn C. Draheim
Dissertations, Theses, and Masters Projects
No abstract provided.
Natural Variation In The Vertical Distribution Of Macrobenthic Invertebrates Within Sandy-Mud Habitats, Amanda Maxemchuk-Daly
Natural Variation In The Vertical Distribution Of Macrobenthic Invertebrates Within Sandy-Mud Habitats, Amanda Maxemchuk-Daly
Dissertations, Theses, and Masters Projects
No abstract provided.
Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi
Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi
Dissertations, Theses, and Masters Projects
Blue marlin diversity was assessed at mtDNA, scnDNA, microsatellite DNA, and allozyme molecular markers. Hierarchical analysis of molecular variance (AMOVA) revealed that most genetic variation was maintained within populations, with a non-significant fraction attributable to variation among temporal replicates and between locations within oceans. In contrast, inter-ocean divergence was highly significant for a majority of loci within each marker class. Previous studies of mitochondrial DNA (mtDNA; n = 104) genetic variation within the blue marlin revealed two distinct clades of haplotypes, one of which was present only in the Atlantic (the 'Atlantic clade'), at a frequency of 40% &(F\sb{lcub}st{rcub}& = …
Variation Between Sparrows In The Ability To Extract Buried Seed, David Michael Whalen
Variation Between Sparrows In The Ability To Extract Buried Seed, David Michael Whalen
Dissertations, Theses, and Masters Projects
No abstract provided.
The Agroecologies Of A Southern Community: The Tye River Valley Of Virginia, 1730-1860, Lynn A. Nelson
The Agroecologies Of A Southern Community: The Tye River Valley Of Virginia, 1730-1860, Lynn A. Nelson
Dissertations, Theses, and Masters Projects
The farmers of piedmont Virginia's Tye River Valley adapted agriculture to a commercial frontier during the eighteenth century. This 'frontier agroecosystem' optimized labor returns by exploiting the stored fertility of mature ecosystems at the expense of conservation, but proved vulnerable to population growth and soil exhaustion. Out-migration increased after the Revolution, and economic growth was stymied by limited capital and consumer formation. The frontier agroecosystem could not provide the reliable commercial returns needed to promote development or stable neighborhoods.;During the early 1800s, prominent planters demanded that Virginia farming be intensified---that land productivity be maximized, rather than labor productivity. This strategy, …
Caribbean Spiny Lobster And Their Molluscan Prey: Are Top-Down Forces Key In Structuring Prey Assemblages In A Florida Bay Seagrass System, Martha Nizinski
Caribbean Spiny Lobster And Their Molluscan Prey: Are Top-Down Forces Key In Structuring Prey Assemblages In A Florida Bay Seagrass System, Martha Nizinski
Dissertations, Theses, and Masters Projects
Relative importance of predator-prey dynamics and several environmental variables in structuring gastropod and bivalve diversity and distribution was investigated in the subtropical seagrass and macroalgal community of Florida Bay, a highly productive system and primary nursery and foraging ground for finfish and invertebrate predators, including the numerically dominant Caribbean spiny lobster, Panulirus argus. The molluscan assemblage, a primary food source for P. argus in particular, is speciose (75 gastropod and 25 bivalve species) and a significant component of epifaunal and infaunal invertebrate assemblages within Florida Bay. Two experimental areas, located within separate basins and each comprised of two experimental sites, …
Phenotypic Clines In The Intertidal Snail Littorina Obtusata: The Role Of Water Temperature And Predator Effluent As Inducers Of Phenotypic Plasticity And Associated Trade-Offs In Shell Form, Geoffrey Clayton Trussell
Phenotypic Clines In The Intertidal Snail Littorina Obtusata: The Role Of Water Temperature And Predator Effluent As Inducers Of Phenotypic Plasticity And Associated Trade-Offs In Shell Form, Geoffrey Clayton Trussell
Dissertations, Theses, and Masters Projects
I examined variability in the shell form of 25 Littorina obtusata populations from Massachusetts to northern Maine. I chose this scale because the history of one of L. obtusata's principal predators, the crab Carcinus maenas, has changed dramatically in the past 100 years. Before 1900, Carcinus did not occur north of Cape Cod, Massachusetts, but by 1950 it had reached Canadian border. Moreover, in summer water temperatures during average 6-8&\sp\circ&C colder at northern locations. Shell thickness and mass increased and body mass decreased with increasing latitude. to test whether these patterns reflect plasticity in response to predators, snails from two …
Interactive Effects Of Cadmium And Benzo(A)Pyrene In Mummichog (Fundulus Heteroclitus), Peter Van Den Hurk
Interactive Effects Of Cadmium And Benzo(A)Pyrene In Mummichog (Fundulus Heteroclitus), Peter Van Den Hurk
Dissertations, Theses, and Masters Projects
When animals are exposed to mixtures of environmental pollutants, it is generally assumed that the toxic effects of the individual components are additive. However, examples of synergistic and antagonistic effects have been described. to study the mechanisms of interaction between a metal and a polycyclic aromatic hydrocarbon, mummichog (Fundulus heteroclitus) were injected with combinations of cadmium (Cd) and benzo (a) pyrene (BP). Measured effect parameters were: mortality, BP-metabolite production in isolated hepatocytes and microsomes, hepatic induction of CYP1A (the BP metabolizing enzyme) and metallothionein (the Cd binding protein), and biliary excretion of BP-metabolites. The mortality data demonstrated that both synergistic …
Habitat Use, Secondary Production, And Trophic Export By Salt Marsh Nekton In Shallow Waters, Giancarlo Cicchetti
Habitat Use, Secondary Production, And Trophic Export By Salt Marsh Nekton In Shallow Waters, Giancarlo Cicchetti
Dissertations, Theses, and Masters Projects
I used 1.75 m&\sp2& drop rings and throw rings to sample communities of nekton at high and low tides in contiguous salt marshes, unvegetated flats, and seagrass beds (Ruppia maritima) of lower Chesapeake Bay. Thirty-two species of nekton were captured between June and October 1995, with a mean overall abundance of 28.6 inds m&\sp{lcub}-2{rcub}& and a mean biomass of 3.8 g m&\sp{lcub}-2{rcub}& (dry weight, dw). Blue crabs, Callinectes sapidus, were the biomass dominants and used seagrass and marsh edge habitats extensively from recruitment to maturity. Palaemonetes shrimp were the most abundant nekton; patterns of allopatry and apparent sympatry were found …
Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford
Dissertations, Theses, and Masters Projects
Phylogenetic and historical biogeographic hypotheses were explored for three groups of teleost fishes that are hypothesized to share a common biogeographic track. Distributed across the eastern Pacific/eastern Atlantic (EP/EA) biogeographic track of Rosen (1975) are the Scomberomorus regalis (Scombridae), Strongylura marina (Belonidae) and Hyporhamphus unifasciatus (Hemiramphidae) species groups comprised of one eastern Atlantic; three, three and four western Atlantic; and two, two and four eastern Pacific species, respectively, for each group. In addition, two species in the Strongylura marina and Hyporhamphus unifasciatus groups, have invaded freshwater drainages of Central and South America. Each of the three species groups were found …