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Full-Text Articles in Life Sciences

Comparative Toxicity Of Creosote And Creosote Contaminated Sediments, Padma T. Venkatraman Jan 1994

Comparative Toxicity Of Creosote And Creosote Contaminated Sediments, Padma T. Venkatraman

Dissertations, Theses, and Masters Projects

No abstract provided.


Uptake Routes Of Benzo[A]Pyrene In An Estuarine Killifish: Cytochrome P4501a Immunohistochemistry Using Whole Fish, Maria Karin Cochran Jan 1994

Uptake Routes Of Benzo[A]Pyrene In An Estuarine Killifish: Cytochrome P4501a Immunohistochemistry Using Whole Fish, Maria Karin Cochran

Dissertations, Theses, and Masters Projects

No abstract provided.


In Vitro And In Vivo Effects Of Chemotherapeutants On The Oyster Parasite, Perkinsus Marinus, Gustavo W. Calvo Jan 1994

In Vitro And In Vivo Effects Of Chemotherapeutants On The Oyster Parasite, Perkinsus Marinus, Gustavo W. Calvo

Dissertations, Theses, and Masters Projects

To investigate the potential of chemotherapeutants to control the oyster pathogen Perkinsus marinus, anticoccidial and antifungal compounds were tested in vitro on infected hemolymph and cultured P. marinus cells and in vivo on infected oysters. In addition, acute toxicity to oysters was determined for six anticoccidials. In vitro experiments with infected hemolymph consisted of 24 h exposure of 0.2 mL hemolymph aliquots to concentrations ranging from 100 mg/L to 0.01 mg/L of amphotericin-B, amprolium, arprinocid, cycloheximide, lasalocid, malachite green, monensin, sulfadimethoxine, and a potentiated sulfadimethoxine, followed by incubation in fluid thioglycollate medium (FTM) to determine prezoosporangia abundance. Lasalocid, malachite green, …


Age, Growth And Population Dynamics Of The Sandbar Shark, Carcharhinus Plumbeus, At Different Population Levels, Thomas R. Sminkey Jan 1994

Age, Growth And Population Dynamics Of The Sandbar Shark, Carcharhinus Plumbeus, At Different Population Levels, Thomas R. Sminkey

Dissertations, Theses, and Masters Projects

The objectives of my research were to test the hypothesis that compensatory (density-dependent) growth of sandbar shark (Carcharhinus plumbeus) occurred after severe population reduction, to describe the juvenile sandbar shark fauna present in the Chesapeake Bay during 1980-81 and 1990-93, and to perform demographic analyses to examine potential population growth. Age and growth of sandbar sharks were investigated by counting rings in vertebral samples collected in 1980-81 and 1991-92. Age at maturity was 15-16 years for both sample periods and both sexes. For sexes combined, the von Bertalanffy growth parameters were L&\sb{lcub}\infty{rcub}& = 199 cm precaudal length (PCL), K = …


Global Phylogeography Of Yellowfin Tuna, Thunnus Albacares, And Mackerels Of The Genus Scomber, Daniel R. Scoles Jan 1994

Global Phylogeography Of Yellowfin Tuna, Thunnus Albacares, And Mackerels Of The Genus Scomber, Daniel R. Scoles

Dissertations, Theses, and Masters Projects

Intraspecific genetic relationships within yellowfin tuna, Thunnus albacares, and three mackerels of the genus Scomber were studied by restriction fragment length polymorphism (RFLP) analysis of mitochondrial DNA (mtDNA). The comparison of these scombrids, with different larval distributions, adult distributions, and vagilities, served to investigate the hypothesis that population structure in marine fishes results from geographic and physical oceanographic processes that limit dispersal of early life history stages. Samples of 20 yellowfin tuna were examined from each of five Pacific locations and one Atlantic location. MtDNA analysis with 12 informative restriction endonucleases demonstrated considerable genetic variation, as evidenced by overall nucleon …


The Role Of Predation On Zostera Marina L (Eelgrass) Seed Abundance, James Fishman Jan 1994

The Role Of Predation On Zostera Marina L (Eelgrass) Seed Abundance, James Fishman

Dissertations, Theses, and Masters Projects

No abstract provided.


Toxicity Resistance In Mummichog (Fundulus Heteroclitus) From A Chemically Contaminated Environment, Cynthia A. H. Williams Jan 1994

Toxicity Resistance In Mummichog (Fundulus Heteroclitus) From A Chemically Contaminated Environment, Cynthia A. H. Williams

Dissertations, Theses, and Masters Projects

No abstract provided.


A Gis Spatial Analysis Of The Potential Conflict Between Submerged Aquatic Vegetation Management And The Development Of Shellfish Aquaculture In The Lower Chesapeake Bay, Laura Ann Grignano Jan 1994

A Gis Spatial Analysis Of The Potential Conflict Between Submerged Aquatic Vegetation Management And The Development Of Shellfish Aquaculture In The Lower Chesapeake Bay, Laura Ann Grignano

Dissertations, Theses, and Masters Projects

No abstract provided.


Functional Characterization Of The Electrophoretic Hemoglobin Polymorphism In The Atlantic Croaker (Micropogon Undulatus), Daniel Allen Shelly Jan 1994

Functional Characterization Of The Electrophoretic Hemoglobin Polymorphism In The Atlantic Croaker (Micropogon Undulatus), Daniel Allen Shelly

Dissertations, Theses, and Masters Projects

No abstract provided.


Social Influences On Reproductive Maturation In Female White-Footed Mice (Peromyscus Leucopus Noveboracensis), Michelle Lee Mabry Jan 1994

Social Influences On Reproductive Maturation In Female White-Footed Mice (Peromyscus Leucopus Noveboracensis), Michelle Lee Mabry

Dissertations, Theses, and Masters Projects

No abstract provided.


Mechanisms Of Larval Spot Transport And Recruitment To The Chesapeake Bay, Deborah A. Bodolus Jan 1994

Mechanisms Of Larval Spot Transport And Recruitment To The Chesapeake Bay, Deborah A. Bodolus

Dissertations, Theses, and Masters Projects

The spot (Leiostomus xanthurus) is an important commercial and recreational species in Virginia. Recruitment of juveniles to the Bay is characterized by large interannual fluctuations, that can be explained by the sequence and direction of wind during various phases of the early life history. An environmentally-modified Ricker stock-recruitment curve was developed incorporating the southeasterly winds in November-December, the southerly winds in January-March, and the westerly winds in April-May. This model explained 81% of the variation and closely paralleled the VIMS Juvenile Spot Index. Spot from the Chesapeake Bay migrate south in fall to spawn near or south of Cape Hatteras. …


Contributions To The Early Life Histories Of Alewife (Alosa Pseudoharengus) And Blueback Herring (Alosa Aestivalis): Rearing, Identification, Ageing, And Ecology, Edward Norbert Sismour Jan 1994

Contributions To The Early Life Histories Of Alewife (Alosa Pseudoharengus) And Blueback Herring (Alosa Aestivalis): Rearing, Identification, Ageing, And Ecology, Edward Norbert Sismour

Dissertations, Theses, and Masters Projects

Early life histories of alewife (Alosa pseudoharengus) and blueback herring (A. aestivalis), collectively known as river herring, are poorly documented for Chesapeake Bay populations. Improved knowledge of these early life histories potentially will aid fisheries, habitat and resource management. Investigations were conducted following two lines. First, alewife and blueback herring larvae reared from eggs were used to investigate methods for species identification and to validate the otolith increment method for age determination. Blueback herring larvae hatched from naturally-spawned eggs were reared to age 24 d. Alewife and blueback herring larvae hatched from artificially-spawned eggs were reared to age 32 d …


Mitochondrial Dna Variation In Natural And Cultured Populations Of The Bay Scallop, Argopecten Irradians (Lamarck) And The Calico Scallop, Argopecten Gibbus (Dall), Sandra Grace Blake Jan 1994

Mitochondrial Dna Variation In Natural And Cultured Populations Of The Bay Scallop, Argopecten Irradians (Lamarck) And The Calico Scallop, Argopecten Gibbus (Dall), Sandra Grace Blake

Dissertations, Theses, and Masters Projects

No abstract provided.


Use Of A Landscape-Level Approach To Determine The Habitat Requirements Of The Yellow-Crowned Night-Heron, Nycticorax Violaceus, In The Lower Chesapeake Bay, Ellen L. Bentley Jan 1994

Use Of A Landscape-Level Approach To Determine The Habitat Requirements Of The Yellow-Crowned Night-Heron, Nycticorax Violaceus, In The Lower Chesapeake Bay, Ellen L. Bentley

Dissertations, Theses, and Masters Projects

No abstract provided.


Oyster (Crassostrea Virginica) Metamorphosis: Effects Of Low Oxygen, Shirley Marie Baker Jan 1994

Oyster (Crassostrea Virginica) Metamorphosis: Effects Of Low Oxygen, Shirley Marie Baker

Dissertations, Theses, and Masters Projects

The objective of my research was to examine the physiology and behavior of metamorphosing oysters, Crassostrea virginica, and to investigate the effects of low oxygen stress on metamorphic processes. Specifically, I examined the effects of hypoxia (20% of air saturation) and microxia (&<&1% of air saturation) on settlement, survival, growth, morphology, metabolic rate and feeding on post-settlement oysters. All of the functions I measured were adversely affected by hypoxia and microxia, compared to normoxic controls. Survival times indicate that, like larvae and adults, post-settlement oysters are capable of anaerobic metabolism. The 2 week period following settlement is especially critical to recruitment. Low oxygen conditions increases mortality and have detrimental effects on the development and growth of post-settlement oysters. Oysters have the ability to feed at nearly all stages of settlement and metamorphosis. While hypoxic conditions reduce feeding only in the youngest metamorphosing oysters, microxic conditions affect all ages. Not only does weight-specific metabolism decrease as the oysters grow, but metabolic responses to low oxygen change from relatively oxygen independent to oxygen dependent. I conclude that oyster distribution may be influenced by low oxygen, especially in those areas that experience prolonged (24-48 h) hypoxia or severe microxic events. Low oxygen events may control recruitment into the adult population directly, because of larval settlement failure and post-settlement mortality, and indirectly, because of reduction in feeding, development rate, and growth of post-settlement oysters.


Colonial Virginia's Cooking Dynasty: Women's Spheres And Culinary Arts, Katharine E. Harbury Jan 1994

Colonial Virginia's Cooking Dynasty: Women's Spheres And Culinary Arts, Katharine E. Harbury

Dissertations, Theses, and Masters Projects

No abstract provided.


Novel Suicide Elements For Gene Disruption In Escherichia Coli, Brian Christopher Nicholson Jan 1994

Novel Suicide Elements For Gene Disruption In Escherichia Coli, Brian Christopher Nicholson

Dissertations, Theses, and Masters Projects

No abstract provided.


Population Genetics Of Selected Species Of Sharks, Edward J. Heist Jan 1994

Population Genetics Of Selected Species Of Sharks, Edward J. Heist

Dissertations, Theses, and Masters Projects

Molecular genetic techniques were used to elucidate genetic population structure in three species of sharks, the coastal sandbar shark (Carcharhinus plumbeus) and Atlantic sharpnose shark (Rhizoprionodon terraenovae), and the pelagic shortfin mako (Isurus oxyrinchus). Allozyme analysis and analysis of restriction fragment length polymorphisms (RFLP) of mitochondrial DNA (mtDNA) were used to test the null hypothesis that the mid-Atlantic Bight and the Gulf of Mexico sandbar sharks consist of a single gene pool. RFLP analysis of mtDNA was used to determine the pattern and level of genetic divergence in the sandbar shark between the western North Atlantic and the Eastern Indian …


Life History And Fisheries Ecology Of Weakfish, Cynoscion Regalis, In The Chesapeake Bay Region, Susan Lowerre-Barbieri Jan 1994

Life History And Fisheries Ecology Of Weakfish, Cynoscion Regalis, In The Chesapeake Bay Region, Susan Lowerre-Barbieri

Dissertations, Theses, and Masters Projects

Otoliths, scales, dorsal spines, and pectoral fin rays were compared to determine the best hardpart for ageing weakfish, Cynoscion regalis. Sectioned otoliths showed the clearest marks and were validated by the marginal increment method for ages 1-5. Traditionally-used scales were found to be less-precise and to underage older fish. Most weakfish from the Chesapeake Bay region were 200-600 mm TL and ages 1-4. Weakfish were not fully-recruited to commercial foodfish grades until age 2. Maximum observed age was 17 from a Delaware Bay fish collected in 1985. Current maximum observed ages were age 12 in Chesapeake Bay and age 11 …


Cell Division In The Multicellular Marine Red Alga Agardhiella Subulata, Karel Joan Klepacki Jan 1994

Cell Division In The Multicellular Marine Red Alga Agardhiella Subulata, Karel Joan Klepacki

Dissertations, Theses, and Masters Projects

No abstract provided.


Increase In Rem Density: A Biological Marker Of Bulimia And Depression Or An Artifact Of Perceived Stress?, Jeannie Hee-Jin Koo Jan 1994

Increase In Rem Density: A Biological Marker Of Bulimia And Depression Or An Artifact Of Perceived Stress?, Jeannie Hee-Jin Koo

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effects Of Contaminated Sediment On The Epidermal Goblet Cells Of The Mummichog, Fundulus Heteroclitus, Laurent C. Mézin Jan 1994

The Effects Of Contaminated Sediment On The Epidermal Goblet Cells Of The Mummichog, Fundulus Heteroclitus, Laurent C. Mézin

Dissertations, Theses, and Masters Projects

Secretion of mucus by epidermal goblet cells is an important first line of defense for teleosts. It protects them against many of the biological, physical and chemical insults they encounter in their environment. This project monitored changes in hemoglobin concentration in epidermal mucus and in the density, diameter and mucus quality of epidermal goblet cells in the mummichog, Fundulus heteroclitus, following exposure to creosote-contaminated sediment. Male fish (200) were exposed for 13 days in flowthough aquaria to either an uncontaminated reference sediment or contaminated sediment containing 30% Elizabeth River sediment. Fish were sampled on Days 0, 3, 7 and 13. …


Measurement Of In Situ Eelgrass Community Metabolism In Standing And Flowing Waters: Methods And Models, William James Seufzer Jan 1994

Measurement Of In Situ Eelgrass Community Metabolism In Standing And Flowing Waters: Methods And Models, William James Seufzer

Dissertations, Theses, and Masters Projects

No abstract provided.


The Vascular Flora Of The Tar Bay And Powell Creek Watersheds, Prince George County, Virginia, Mark Eugene Mort Jan 1994

The Vascular Flora Of The Tar Bay And Powell Creek Watersheds, Prince George County, Virginia, Mark Eugene Mort

Dissertations, Theses, and Masters Projects

No abstract provided.


Predation On Juvenile Blue Crabs, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay: Patterns, Predators, And Potential Impacts, Kirt E. Moody Jan 1994

Predation On Juvenile Blue Crabs, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay: Patterns, Predators, And Potential Impacts, Kirt E. Moody

Dissertations, Theses, and Masters Projects

Various investigations of the population dynamics of blue crabs in Chesapeake Bay indicate that predator-induced mortality in the juvenile phase may determine year-class strength. In a tethering study, which spanned three seasons in shallow-water habitats of the lower York River, daily mortality rates of juvenile crabs were measured across three variables: crab size (30-70 mm carapace width), habitat type (seagrass, mud, and sand), and month (May-November). Vulnerability to predation was consistently lower for larger crabs, approaching a size refuge from predation at approximately 90 mm carapace width. Predation was most intense in unvegetated sand habitats, and significantly lower in seagrass …


Reproductive Strategies In Asclepias Syriaca And Apocynum Cannabinum, Mariellen J. Soltys Jan 1994

Reproductive Strategies In Asclepias Syriaca And Apocynum Cannabinum, Mariellen J. Soltys

Dissertations, Theses, and Masters Projects

No abstract provided.


The Isolation And Characterization Of A Novel G-Protein-Coupled Receptor Involved In Angiogenesis, Rebecca Ruth Stucki Miles Jan 1994

The Isolation And Characterization Of A Novel G-Protein-Coupled Receptor Involved In Angiogenesis, Rebecca Ruth Stucki Miles

Dissertations, Theses, and Masters Projects

No abstract provided.


Xenopus Laevis Ribosomal Protein S1: Evidence For Regulation At The Transcriptional Level, Cleve Ray-Dean Sinor Jan 1994

Xenopus Laevis Ribosomal Protein S1: Evidence For Regulation At The Transcriptional Level, Cleve Ray-Dean Sinor

Dissertations, Theses, and Masters Projects

No abstract provided.


Size-Specific Fecundity Of The Sea Scallop, Placopecten Magellanicus, During One Spawning Period In The Mid-Atlantic Resource Area, Ryan B. Carnegie Jan 1994

Size-Specific Fecundity Of The Sea Scallop, Placopecten Magellanicus, During One Spawning Period In The Mid-Atlantic Resource Area, Ryan B. Carnegie

Dissertations, Theses, and Masters Projects

No abstract provided.


Food, Feeding, And Length-Weight Relationships Of Young-Of-The-Year Striped Bass, Morone Saxatilis And Young-Of-The-Year White Perch, Morone Americana, Paul J. Rudershausen Jan 1994

Food, Feeding, And Length-Weight Relationships Of Young-Of-The-Year Striped Bass, Morone Saxatilis And Young-Of-The-Year White Perch, Morone Americana, Paul J. Rudershausen

Dissertations, Theses, and Masters Projects

No abstract provided.