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Full-Text Articles in Life Sciences

Studies On The Oyster Pathogen Perkinsus Marinus (Apicomplexa): Interactions With Host Defenses Of Crassostrea Virginica And Crassostrea Gigas, And In Vitro Propagation, Jerome F. La Peyre Jan 1993

Studies On The Oyster Pathogen Perkinsus Marinus (Apicomplexa): Interactions With Host Defenses Of Crassostrea Virginica And Crassostrea Gigas, And In Vitro Propagation, Jerome F. La Peyre

Dissertations, Theses, and Masters Projects

The disease caused by the protozoan Perkinsus marinus has been a major source of mortality in the eastern oyster, Crassostrea virginica. Variations in susceptibility to P. marinus infection among eastern oysters collected from the Chesapeake Bay and Gulf of Mexico, as well as between eastern and Pacific (Crassostrea gigas) oysters were determined. Since oyster host defense may play a role in determining susceptibility to pathogen infection, cellular and humoral defense activities of the oyster and their interactions with P. marinus were investigated. Procedures also had to be established to isolate, purify, and propagate in vitro, P. marinus. Eastern oysters from ...


Life History, Population Dynamics And Yield-Per-Recruit Modeling Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Area, Luiz R. Barbieri Jan 1993

Life History, Population Dynamics And Yield-Per-Recruit Modeling Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Area, Luiz R. Barbieri

Dissertations, Theses, and Masters Projects

Otoliths, scales, dorsal spines, and pectoral fin rays, of Atlantic croaker, Micropogonias undulatus, were compared for legibility of presumed annuli and precision in repeated readings, to determine the best structure for ageing. Marks on transverse otolith sections were easiest to read and showed the best agreement between readings. Fish collected in Chesapeake Bay and in Virginia and North Carolina coastal waters during 1988-1991 were then aged using otolith sections. Ages 1-8 were recorded, but eight-year-old fish were rare. Marginal increment analysis showed that for ages 1-7 annuli are formed once a year during the period April-May. Otolith age readings were ...


Immigration Of Blue Crab (Callinectes Sapidus) Megalopae In The York River, Virginia: Patterns And Processes, Eugene J. Olmi Iii Jan 1993

Immigration Of Blue Crab (Callinectes Sapidus) Megalopae In The York River, Virginia: Patterns And Processes, Eugene J. Olmi Iii

Dissertations, Theses, and Masters Projects

Following larval development in coastal waters, the postlarval stage, the megalopa, of the blue crab enters estuaries and colonizes juvenile/adult habitats. I examined the dynamics of the immigration of blue crab megalopae in the York River, Virginia. Plankton samples were collected nightly during flood tide in the York River Jul-Nov 1987, 1988 and 1989 to quantify variation in abundance of blue crab megalopae during the recruitment season. The abundance of megalopae was highly episodic, and significantly correlated with wind stress to the west (1987, 1988 and 1989), wind stress to the north (1989), and observed tidal range at Gloucester ...


Comparison Of Uptake And Disposition Of Organic Pollutants In Intermolt And Ecdysial Blue Crabs, Callinectes Sapidus, Judy Lynne Haner Jan 1993

Comparison Of Uptake And Disposition Of Organic Pollutants In Intermolt And Ecdysial Blue Crabs, Callinectes Sapidus, Judy Lynne Haner

Dissertations, Theses, and Masters Projects

No abstract provided.


Responses Of Cytochrome P450ia In Freshwater Fish Exposed To Pulp Mill Effluents In Experimental Stream Channels, Laura Anne Bankey Jan 1993

Responses Of Cytochrome P450ia In Freshwater Fish Exposed To Pulp Mill Effluents In Experimental Stream Channels, Laura Anne Bankey

Dissertations, Theses, and Masters Projects

No abstract provided.


Dynamics Of Fish Assemblages Associated With An Offshore Artificial Reef In The Southern Mid-Atlantic Bight, Aaron J. Adams Jan 1993

Dynamics Of Fish Assemblages Associated With An Offshore Artificial Reef In The Southern Mid-Atlantic Bight, Aaron J. Adams

Dissertations, Theses, and Masters Projects

No abstract provided.


Forest Fires In Western Europe In 1987, Philippe Le Canut Jan 1993

Forest Fires In Western Europe In 1987, Philippe Le Canut

Dissertations, Theses, and Masters Projects

No abstract provided.


Ultrastructure And Mitosis Of Glaucosphaera Vacuolata, Steven Philip Allan Goss Jan 1993

Ultrastructure And Mitosis Of Glaucosphaera Vacuolata, Steven Philip Allan Goss

Dissertations, Theses, and Masters Projects

No abstract provided.


Stripping And Reassembly Of The Yeast Vacuolar H+-Atpase Peripheral Protein Subunits, Heather R. Yarashus Jan 1993

Stripping And Reassembly Of The Yeast Vacuolar H+-Atpase Peripheral Protein Subunits, Heather R. Yarashus

Dissertations, Theses, and Masters Projects

No abstract provided.


The Structure Of The Holocephalan Head And The Relationships Of The Chondrichthyes, Eileen D. Grogan Jan 1993

The Structure Of The Holocephalan Head And The Relationships Of The Chondrichthyes, Eileen D. Grogan

Dissertations, Theses, and Masters Projects

The interrelationship of the chondrichthyan subclasses is evaluated based on divergence in the nature of the suspensorium, the preorbital cranial anatomy, the distribution of major venous sinuses and localization of hematopoietic tissue. The anatomy of representative extant taxa was examined by radiography and/or dissection. Fossil selachians, paraselachians, and holocephalans of the Bear Gulch of Montana, U.S.A. (Mississippian, Namurian E2B) were studied for evidence of vascular pigmentation, suspensorium, and cranial, branchial, and pectoral anatomy. These studies validate the suspensorial condition of autodiastyly and suggest autodiastyly is a fundamental condition involved in the basic radiation of Chondrichthyes. The plesiomorphous ...


Gill Surface Area In Relation To Growth Rates And Maximum Size In Sharks, David Noboru Hata Jan 1993

Gill Surface Area In Relation To Growth Rates And Maximum Size In Sharks, David Noboru Hata

Dissertations, Theses, and Masters Projects

The most commonly used equation to describe size at age in fishes is the von Bertalanffy equation (VBE), which assumes that growth rate is based on the balance of anabolic and catabolic processes: dW/dt = HW&\sp{lcub}\rm d{rcub}&-kW&\sp{lcub}\rm m{rcub}&. Anabolism, HW&\sp{lcub}\rm d{rcub}&, is considered proportional to gill surface area (A = rW&\sp{lcub}\rm d{rcub}&), and a "generalized" VBE (GVBE) has been previously determined: L&\sb{lcub}\rm t{rcub}& = L&\sb\infty&(1-exp(-KD(t-t&\sb{lcub}\rm O{rcub})))\sp{lcub}\rm 1/D{rcub ...


Movements And Behavior Of Wild And Head-Started Sea Turtles, John A. Keinath Jan 1993

Movements And Behavior Of Wild And Head-Started Sea Turtles, John A. Keinath

Dissertations, Theses, and Masters Projects

Flipper-tagging, aerial surveys, and satellite telemetry was used to investigate the occurrence, migratory routes, distances traveled, swimming speeds, diving behavior, and the relation of water temperature to movements and timing of migration of wild loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) sea turtles. The behavior and movements of head-started loggerhead turtles was investigated with satellite telemetry and compared to wild turtles. Flipper-tagged loggerhead and Kemp's ridley turtles inhabit Chesapeake Bay during the warm months and many return in subsequent seasons. Aerial surveys showed that loggerhead turtles migrate from south of Cape Hatteras to northern waters during May ...


Characterization Of Anti-Tumor Immunity In Oyster Toadfish (Opsanus Tau), And The Effects Of 7,12 -Dimethylbenz(A)Anthracene On This Immune Response, Kenneth R. Seeley Jan 1993

Characterization Of Anti-Tumor Immunity In Oyster Toadfish (Opsanus Tau), And The Effects Of 7,12 -Dimethylbenz(A)Anthracene On This Immune Response, Kenneth R. Seeley

Dissertations, Theses, and Masters Projects

Cell-mediated lysis of cultured tumor target cells by nonspecific cytotoxic cells (NCC) was examined in the oyster toadfish (Opsanus tau), an estuarine teleost. NCC activity was evaluated in cells taken from the head kidney, peripheral blood, spleen and peritoneal cavity. NCC activity was a property of plastic nonadherent cells which lacked phagocytic activity, indicating that in terms of their functional capacity, the cells which mediate nonspecific cytoxic immune responses in oyster toadfish do not appear to be monocytes or macrophages. However, light and electron microscopic examination of these cells revealed that morphologically, they resemble monocytes and macrophages. A new technique ...


Interspecific And Intraspecific Variability In Placoid Scale Morphology In Relation To Body Form Variability In Squaliformes, Christopher R. Tabit Jan 1993

Interspecific And Intraspecific Variability In Placoid Scale Morphology In Relation To Body Form Variability In Squaliformes, Christopher R. Tabit

Dissertations, Theses, and Masters Projects

An ontogenetic series of nine species; Centrophorus granulosus, Centroscymnus coelolepis, Dalatias licha, Deania calcea, Echinorhinus cookei, Isistius brasiliensis, Oxynotus centrina and Squalus acanthias were studied to determine swimming capabilities, boundary-layer flow conditions and placoid scale functional morphologies. Body morphometric variables included the girth and the distance from snout to the orbitals, origin of the median and paired fins, and the caudal peduncle, body and fin surface area, fin aspect ratios and caudal fin angles. Placoid scales were sampled from sixteen regions across the body. Morphometric variables included the number of scales per area of integument, scale crown width, length and ...


Human Impacts On Beach Use By Wintering And Migrating Birds In The Lower Chesapeake Bay, Ellen Fitzsimmons Mclean Jan 1993

Human Impacts On Beach Use By Wintering And Migrating Birds In The Lower Chesapeake Bay, Ellen Fitzsimmons Mclean

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of The Habitat And Size-Specific Predation On The Ontogenetic Shift In Habitat Use By Newly Settled Blue Crabs, Callinectes Sapidus, Adele J. Pile Jan 1993

Effects Of The Habitat And Size-Specific Predation On The Ontogenetic Shift In Habitat Use By Newly Settled Blue Crabs, Callinectes Sapidus, Adele J. Pile

Dissertations, Theses, and Masters Projects

No abstract provided.


The Dynamics Of An Oligohaline, Macrofaunal, Fouling Community, Michelle Lynne Thompson Neubauer Jan 1993

The Dynamics Of An Oligohaline, Macrofaunal, Fouling Community, Michelle Lynne Thompson Neubauer

Dissertations, Theses, and Masters Projects

No abstract provided.


Amorphometric And Meristic Study Of The Halfbeak, Hyporhamphus Unifasciatus (Teleostei: Hemiramphidae) From The Western Atlantic, With The Description Of A New Species, Heidi M. Banford Jan 1993

Amorphometric And Meristic Study Of The Halfbeak, Hyporhamphus Unifasciatus (Teleostei: Hemiramphidae) From The Western Atlantic, With The Description Of A New Species, Heidi M. Banford

Dissertations, Theses, and Masters Projects

No abstract provided.


Growth Response Of Eelgrass (Zostera Marina L) To Root-Rhizome And Whole Plant Exposure To Atrazine, Arthur C. Schwarzschild Jan 1993

Growth Response Of Eelgrass (Zostera Marina L) To Root-Rhizome And Whole Plant Exposure To Atrazine, Arthur C. Schwarzschild

Dissertations, Theses, and Masters Projects

No abstract provided.


Distribution Of Organochlorine Pollutants In Sea Turtles, Mary J. Rybitski Jan 1993

Distribution Of Organochlorine Pollutants In Sea Turtles, Mary J. Rybitski

Dissertations, Theses, and Masters Projects

No abstract provided.


Burden In Spousal Caregivers: A Correlational Study Of The Effect And Interaction Of Stressors, Vulnerability, Psychological Resources And Social Supports On The Development Of Burden In Spousal Caregivers Of The Chronically Ill, Sheila Marie Crossen-Powell Jan 1993

Burden In Spousal Caregivers: A Correlational Study Of The Effect And Interaction Of Stressors, Vulnerability, Psychological Resources And Social Supports On The Development Of Burden In Spousal Caregivers Of The Chronically Ill, Sheila Marie Crossen-Powell

Dissertations, Theses, and Masters Projects

This study investigated burden in a convenience, nonrandom sample of 120 spousal caregivers of cardiac patients, who resided at home in the Richmond, VA area, had health insurance, and received medical care from private providers. Using Vitaliano's theory that burden is a function of stressors and personal vulnerability moderated by psychological resources and social supports, the study examined the relationships between those five constructs.;Burden was measured by the Brief Symptom Inventory and Montgomery's Scales of Objective and Subjective Burden. The Hassles and Uplifts Scales was used to measure stressors; demographic data and the Self control, Responsibility, Socialization ...


The Relationships Between Retrospective Perceptions Of An Alcoholic Home Environment With Levels Of Differentiation Of Self And Trait Anxiety In Adult Children Of Alcoholics, Barbara Lynn Rojas-Hughes Jan 1993

The Relationships Between Retrospective Perceptions Of An Alcoholic Home Environment With Levels Of Differentiation Of Self And Trait Anxiety In Adult Children Of Alcoholics, Barbara Lynn Rojas-Hughes

Dissertations, Theses, and Masters Projects

The purpose of this study was to investigate the relationships between adult children of alcoholics (ACOA's) recollections of their family of origin home environments, with present day levels of ACOA differentiation of self, and trait anxiety. The author explored the influence of ACOA gender differences and a variety of demographic information.;The ACOA volunteers for this study were recruited from The College of William and Mary in Virginia. to be included in the study, subjects must have met the following criteria: (a) the volunteer's age must have been 18 years or above; (b) subjects met the ACOA criteria ...