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Structure Of A Subtidal Benthic Community Near Cape Charles, Virginia, R. Michael Ewing

Biological Sciences Theses & Dissertations

Species composition, distribution, and abundance of benthic invertebrates of a subtidal community were examined at a location on the lower Delmarva Peninsula near Cape Charles, Virginia. Macrobenthos was sampled quarterly between June, 1977 and June, 1978 at nine sites along a transect in Old Plantation Creek and the adjacent offshore area. Spatial and temporal patterns of numerically important species are discussed.

Sampling sites and species were grouped by a numerical classification strategy which consisted of the Bray-Curtis similarity measure and group-average clustering. Three faunal assemblages were identified with the aid of constancy and fidelity nodal analyses: (1) a tidal creek …

The Synthesis And Evaluation Of The Potential Antineoplastic Activity Of The Semicarbazone And The Thiosemicarbazone Derivatives Of The Di-2-Pyridyl Ketone And The 1,8-Diazafluorenone Ring Systems, Adriene Y. Principe

Chemistry & Biochemistry Theses & Dissertations

A number of' a-(N)-heterocyclic thiosemicarbazones have been synthesized and evaluated for potential antineoplastic activity since Brockman and colleagues2 reported the antineoplastic activity of' 2-f'ormylpyridine thiosemicarbazone (1). The primary objective of' this research project has been the synthesis and characterization of' the semicarbazone and the thiosemicarbazone derivatives of' the di-2-pyridyl ketone, (9-a) and (9-b), and the 1,8-diazaf'luorenone, (10-a) and (10-b), ring systems, as well as the evaluation of' these compounds for both in vitro and in vivo antineoplastic activity against Ehrlich ascites tumor cells in mice. These studies have suggested that di-2-pyridyl ketone thiosemicarbazone (9-b) is as effective as 2-formylpyridine …

The Development Of Techniques For The Enumeration Of Selected Pathogenic Bacteria In Lynnhaven Estuarine Sediments, Mark T. Frank

Biological Sciences Theses & Dissertations

Methodologies for the improved recovery of selected pathogenic bacteria from estuarine sediments were investigated. Laboratory and field studies were conducted to document the sensitivity of the techniques for isolating Salmonella species, Pseudomonas aeruginosa, and Vibrio parahaemolyticus. Vibrio parahaemolyticus-like organisms were enriched in a seawater yeast extract broth and isolated from Thiosulfate Citrate Bile Salts Sucrose plated media. Enrichment procedures with and without elevated temperatures and subsequent transfers to selective and differential plated media have been examined for the isolation of Salmonella species and P. aeruginosa. These pathogens were initially assayed for utilizing primary enrichments of asparagine …

Detection Of Unique Tumor-Associated Proteins In The Urine Of Patients With Transitional Cell Carcinoma By High Resolution Two-Dimensional Polyacrylamide Gel Electrophoresis, Robert David Lehman

Biological Sciences Theses & Dissertations

A two-dimensional polyacrylamide gel electrophoretic technique was developed for the detection of unique tumor-associated proteins in urine of patients with transitional cell carcinoma (TCC) of the urinary bladder. This technique yielded high resolution of polypeptides in the urine of cancer patients. Urine was chosen as a source of tumor-associated components because the location of the tum or should release already solublized tum or substances in to the urine.

Urinary proteins were concentrated and then analyzed by the two - dimensional electrophoretic technique using isoelectric focusing in the first dimension and sodium dodecylsulfate - polyacrylamide gel electrophoresis in the second dimension. …

Swimming As A Determinate To Immigration For Two Small Mammals In Coastal Virginia, Jeffrey Lewis Carter

Biological Sciences Theses & Dissertations

Small mammals were live trapped on the mainland and on an island located in the southeast corner of Virginia. The area was characterized by a mid-Atlantic coastal climate. White-footed mice (Perompsous fsucopus) were trapped on the mainland but not on the island, whereas meadow voles (Microtus psnnsylvimious) inhabited only the island. A series of swimming tests were performed in both the field and in the laboratory on both of these species to determine if swimming abilities could be the factor preventing Pszomysous from colonizing the island.

Both species of small mammals showed good swimming endurance in …

Studies On The Anatomy Of The Parasitic Gymnosperm Parasitaxus Ustus (Podocarpaceaea), Evelyn Wilkinson

Biological Sciences Theses & Dissertations

An anatomical study of the parasitic gymnosperm Parasitaxus ustus was conducted. Material was collected in New Caledonia, embedded in paraffin or celloidin, sectioned and stained. The apical meristem consists of apical initial cells, central mother cells, the peripheral zone, and rib meristem. Leaves are scale-like, triangular and broadly decurrent at their bases. Resin ducts and prominent sclereids are present in leaves and the cortex of the stem. The parasite-host connection is in the form of a xylem to xylem connection in which the tracheids are connected by bordered pits.

Feeding Morphologies And Distribution Patterns Of Marine Cladocera In The Lower Chesapeake Bay, Sandra Layne Gilchrist

OES Theses and Dissertations

Temporal and spatial distributions of marine cladocera in the lower Chesapeake Bay estuary were observed over a year-long sampling period. The distributions of cladoceran species throughout the Bay were studied in relation to temperature and salinity. A survey of the species over the entire Bay is included to establish distribution patterns of the various species during a short time period.

Theoretical mathematical principles were used to predict feeding abilities of the Bay species. Mouthparts are described qualitatively and quantitatively to infer function. A mandibular index developed by Itoh (1970) was revised and employed in evaluating feeding methods interspecifically and interspecifically. …

The Spatial And Temporal Distribution Of Fish Eggs And Larvae In Hempstead Bay Estuary, Joseph Adelard Lessard

OES Theses and Dissertations

The ichthyoplankton of Hempstead Bay estuary was sampled from December 1972 to mid March 1974. Eleven stations were sampled by towing a 0.5 meter diameter plankton net. Eggs were most abundant during June and July with an average concentration calculated to be above 5,500/100m³. Egg densities were the lowest during the fall and winter. Larvae were most frequently taken from March through July with densities varying greatly among the samples. The eggs of Brevoortia tyrannus, Anchoa mitchilli, Tautoga onitis, Tautogolabrus adspersus, and Scophthalmus aguosus and the larvae of Menidia menidia, Ammodvtes hexapterus and Pseudopleuronectes americanus constituted most …

Seasonal Feeding Habits Of The River Otter (Lutra Canadensis) In Ditches Of The Great Dismal Swamp, Ronnie M. Pierce

Biological Sciences Theses & Dissertations

To determine the seasonal feeding habits of the river otter (Lutra canadensis) in the Great Dismal Swamp 209 scats were collected, from May 1977 to May 1978, and analyzed for content. Remains of crayfish were found with a frequency of occurrence of 82% while fish remains occurred in 62% of the scat. This is in direct contrast to previous studies (from other areas) which found fish with a greater frequency than crayfish. Fish consumption was believed to increase during periods of low water or low temperatures. Sunfish were represented most frequently and may be the preferred fish. Amphiuma remains …

Additional Comments On Reproductive Strategies And Population Fluctuations In Microtine Rodents, Michael S. Gaines, William M. Schaffer, Robert K. Rose

Biological Sciences Faculty Publications

Recently, Schaffer and Tamarin (1973) proposed a model relating changes in reproductive effort (RE) to fluctuating densities in microtine rodents (lemmings and voles). They assumed (and presented data supporting this assumption) that the major effect of increased crowding would be a reduction in survival among prereproductives, thereby lowering the effective fecundity (Schaffer and Rosenzweig 1977) of their parents. As a consequence, Schaffer and Tamarin argued that the optimal reproductive expenditure, E(N), should decline with increasing population size, N. They also deduced the shape of the zero-growth isocline, N*(E), for differing levels of RE and plotted both E(N) and N*(E) on …

Development Of Pelagic Larvae And Postlarva Of Squilla Empusa (Crustacea, Stomatopoda), With An Assessment Of Larval Characters Within The Squillidae, Steven G. Morgan, Anthony J. Provenzano Jr.

OES Faculty Publications

Larvae of the predatory crustacean Squilla empusa were collected from the plankton in Chesapeake Bay and reared in the laboratory to permit description of the pelagic stages before the postlarval stage.

Characters such as rostral length and spinulation, carapace spinulation, relative size of telson, overall body size, and appearance probably are of more value for specific than for generic identification. The presence or absence of teeth on the dactylus of the second maxilliped, the presence or absence of a spine on the basis of the second maxilliped, and the number of epipods may be useful characters in determining generic alliances …

A Potential Macroregulatory Mechanism For Growth Regulation In Neurospora Crassa, Martha Mooney

Biological Sciences Theses & Dissertations

Neurospora produces a phase specific, cationic mucopolysaccharide composed primarily of galactosamine (GAG-MP) which becomes part of the cell wall and is later secreted into the media. Its appearance coincides with the onset of the restricted phase of growth and causes efflux of small molecular weight metabolites when incubated with conidial cells. This activity may be a product of electrostatic interactions of the GAG-MP with the conidial plasma membrane. The activity is blocked by acetylation of the primary amines on the molecule, digestion by enzymes that hydrolyze carbohydrate linkages and the inclusion of NaCl (lM) in the GAG-MP/conidia reaction mixture. The …

Animal-Sediment Relationship Study Of The Western Branch Of The Lynnhaven River, Charles Perry Seymour

Biological Sciences Theses & Dissertations

The animal-sediment relationships of the marine benthic infauna of an estuarine river system, Lynnhaven River, Virginia Beach, Virginia, were studied at six sites, sampled bimonthly for one year. Six species were found to dominate all of the sampling periods and sites for the year. The greatest number of individuals, biomass, and species were found at the sand sites. Deposit feeders were recorded in greater number than suspension feeders at both the sand and the mud sites.

Cluster and nodal analyses were successful in demonstrating animal-sediment relationships for the intertidal regions of the river system.