Biology Commons^™

Frequency Of Rickettsia Sps. In Dermacentor Variabilis And Amblyomma Americanum In Central Hanover County, Virginia, Peggy Ann Keefe

Master's Theses

In the eastern United States, Dermacentor variabilis is the primary vector of Rickettsia rickettsii, the etiological agent for Rocky Mountain Spotted Fever. Cases of Rocky Mountain Spotted Fever in eastern United States increased steadily from 1959 to 1979 to a peak of one case per 200,000 people in 1979 (Morbidity and Mortality Weekly Report, 1985). In 1976, 98.9% of the reported cases of Rocky Mountain Spotted Fever were east of the 100th meridian with 1.1% occurring west of the 100th meridian (Burgdorfer, 1977). Hanover County, Virginia is an endemic area for this disease (Sonenshine, 1971); the last reported case was …

Pebble Nest Microhabitats Of Semotilus Species (Pisces: Cyprinidae), James Timothy Magee

Master's Theses

The pebble nest microhabitats of four species of Semotilus were compared. Pit/mound nests of Semotilus corporalis were significantly larger than the pit/ridge nests of Semotilus atromaculatus, Semotilus lumbee, and Semotilus thoreauianus. Nests of S. corporalis were in wider and deeper streams. Pits of S. lumbee nests were longest of the four species; those of S. corporalis were widest and deepest. Semotilus corporalis used a greater proportion of larger stones (23 mm or greater) in nest construction than the other three species. There was no significant difference in the electivity index (percentage of nest pebble sizes versus those of the substrate) …

Regulatory Cell Biology Of Growth Hormone And Prolactin In The Cow Mammary Gland, David Andrew Walkup

Master's Theses

Prolactin (PRL) acts directly on milk secretory cell nuclei to stimulate lactation in rats. In the cow, PRL has been detected in Golgi apparatus, endoplasmic reticulum, and secretory vesicle subcellular fractions of mammary gland , but not nuclear fractions. However, growth hormone {GH) is the galactopoeitic hormone in cows, not PRL. The possibility of GH acting directly on the cow milk secretory cells, and PRL acting on their nuclei was investigated using an immunocytochemical method. PRL and GH were detected in endoplasmic reticular and Golgi apparatus regions of the milk secretory cells, as well as, on nuclear and fat globule …

Transcriptional Control Of The Inducible Nitrate Reductase Isoform In Soybean, Glycine Max, John J. Callaci

Master's Theses

No abstract provided.

A Reverse Genetics Approach For Studying Histone H4 Structure-Function Relationships In Yeast, Michael J. Bonaduce

Master's Theses

A previously constructed mutation of the histone H4 gene has been the subject of a detailed analysis. The mutation involves an H4 gene encoding two amino acid changes which substitute aspartic acid for glycine at positions 13 and 42 of the polypeptide. These substitutions result in a nonfunctional H4 protein when assayed in Saccharomyces cerevisiae. In contrast, an analysis of an amino terminal deletion of amino acids 3-26 results in a functional H4 protein. Physical biochemistry studies identify the sites of histone-histone interactions between residues 38-102 of histone H4, the same area in which position 42 resides. The question being …

A Rapid System For Analyzing Histone H4 Mutations In The Yeast Saccharomyces Cerevisiae, Edward Rex Lakey Harkrader

Master's Theses

Genetically engineered, specific histone H4 mutations have been analyzed in yeast which lack normal H4 protein using the time consuming technique of tetrad dissection. The purpose of the present research project has been to develop a rapid new system for analyzing histone H4 mutations in yeast. The new system has made it possible to isolate quickly cells which are surviving on mutant H4 only. The system will make it possible to analyze more quickly large numbers of H4 mutations. It is termed a plasmid shuttle system because of the use of plasmid vectors for shuttling histone H4 alleles in and …

Sodium/Proton Exchange In The Gills Of Three Species Of Crabs : Libinia Dubia, Callinectes Sapidus, And Menippe Mercenaria, Nicholas J. Maiolo

Master's Theses

Na+/H+ exchange was studied in plasma membrane vesicles from gills of three species of crabs: Callinectes sapidus (blue crab), Libinia dubia (spider crab), and Menippe mercenaria (stone crab). Spider crabs and stone crabs were acclimated to full (35ppt) seawater, while blue crabs were acclimated to both dilute (5ppt) and full strength seawater. Membrane vesicles were prepared by sucrose density centrifugation. Na+/H+ exchange was analyzed using acridine orange fluorescence. Male C. sapidus showed the most exchange activity (per g gill tissue), followed by M. mercenaria, female C. sapidus and Libinia dubia. No difference in exchange activity was evident when blue crabs …

Some Chemical And Physical Factors Influencing Growth Of Panus Stipticus Bulliard Ex Fries And Armillariella Mellea (Vahl Ex Fries) Karsten, James Robert Kirkland

Master's Theses

Two species of wood rotting fungi were used to investigate the possibility that growth-enhancing or inhibitory substances in woods from various trees are responsible for the distribution of these fungi in nature. Panus stipticus (Bulliard ex Fries) and Armillariella mellea (Vahl ex Fries) Karsten were cultured in the laboratory on blocks of wood from Taxodium distichum (L.) Richard, Juniperus virginiana L., Pinus taeda L. and Quercus rubra L. Panus stipticus grew well on the surface of the wood blocks; histological studies showed less penetration into the xylem of the softwoods than into that of Q. rubra. Armillariella mellea grew well …

Characterizing Variants Of The Human Alphoid Sequence Family, Eleni Palamidis-Bourtsos

Master's Theses

No abstract provided.

Feeding Periodicity Of Yellow Perch, Perca Flavescens, (Mitchill), In Southwestern Lake Michigan, Ronald J. Abrant

Master's Theses

No abstract provided.

Structure And Genomic Organization Of Two New Families Of Human Repetitive Dna, Susan L. Carnahan

Master's Theses

No abstract provided.

Age And Growth Of Black Crappie Pomoxis Nigromaculatus In Lake Anna, A Virginia Power Cooling Impoundment, Robert Mason Daniels

Master's Theses

A study of the age and growth of black crappie, Pomoxis nigromaculatus, was conducted in Lake Anna, Virginia, a cooling impoundment for Virginia Power's North Anna Power Station. Growth of the population in the reservoir was compared to that of the population in North Anna's Waste Heat Treatment Facility. Analysis of covariance (ANCOVA) using age as the covariate indicated the growth rate of the two populations did not differ significantly at the .05 level. The populations were combined and tests were conducted to determine differences in growth rates between the sexes. ANCOVA indicated the growth rates of males and females …

Sodium/Proton Exhange In Membrane Vesicles From Crab (Callinected Sapidus And Carcinus Maenas) Gill, Robert Eric Shetlar

Master's Theses

The existence of a sodium-ion-for-hydrogen-ion exchange mechanism in the membranes of certain epithelial cells has been demonstrated by many investigators (Murer et al., 1976; Tsai et al., 1984; Seiler et al., 1985 ) • This mechanism has been shown to exchange one Na+ for one H+ (Aronson & Igarashi, 1986) and is thought to be more prominent in the brush-border membranes (Murer et al., 197 6; Reenstra et al., 1981 ; Ives et al., 1983) of mammalian kidney tubules and intestinal tissues than in basolateral membranes of these tissues. The roles the exchanger plays in the cell may include intracellular …

Reproductive Competence In The Golden Hamster Following Prenatal Alcohol Exposure, Jennifer Jayne Swiatek

Master's Theses

No abstract provided.

Metabolite Control Of Nitrate Reductase Synthesis In Cucurbita Maxima Var. Buttercup, Randall L. Langendorfer

Master's Theses

No abstract provided.

The Biology Of Two Species Of Crayfish In Southwestern Lake Michigan, John P. Quinn

Master's Theses

No abstract provided.

Transcriptional Control Of Nitrate Reductase Synthesis In Squash, Cucurbita Maxima, Susan Martino

Master's Theses

No abstract provided.

Isolation Of The Nitrate Reductase Structural Gene In Cucurbita Maxima, Joyce Ostberg

Master's Theses

No abstract provided.

A Survey Of Cellular Slime Molds At Selected Sites On The James River, Virginia, Nathaniel Lemaster Armistead

Master's Theses

The flood plain of the James River in Virginia supports a variety of deciduous forest associations and has not been examined previously for dictyostelids. This thesis is primarily concerned with the results of a survey of dictyostelids at selected sites in the James River basin. Some incidental observations concerning possible ecological relationships between dictyostelids are included.

Seven of the plant communities of Virginia described by Harvill, Stevens and Ware (1984) afe present in the areas surveyed and collection sites were established accordingly: (1) Mountain Pine-Oak Heath, (2) Pine-Oak Heath, (3) Oak-Hickory Forest, (4) Alluvial Hardwood Forest, (5) Beech-Maple-Tuliptree Forest, (6) …

A Survey Of Cellular Slime Molds At Selected Sites On The James River, Virginia, Nathaniel Lemaster Armistead Iii

Master's Theses

Forty-three sample sites representing seven plant associations were surveyed for cellular slime molds in the James River basin from the head-waters to the mouth of the James River. Dictyostelium mucoroides, Q. minutum, Q. purpureum, D. discoideum, Polysphondylium violaceum and P. pallidum were found in all associations. Dictyostelium lacteum was found in all but the Maple-Basswood association. The remaining species were unique to the Alluvial Hardwood association and the following respective forest types: D. polycephalum to Oak-Hickory, D. giganteum to Oak-Hickory and Mixed Mesophytic, and D. rosarium to Mixed Mesophytic. A percentage similarity test indicated that, with regards to the observed …

Apid Increase In Serum Calcium In Response To Stress In Pomoxis Nigromaculatus, Black Crappie, Severn Borden Churn

Master's Theses

Serum calcium levels were determined colorimetrically in Pomoxis nigromaculatus, the black crappie, subjected to rapid changes in temperature. Two experiments were conducted; in the first, fish were exposed to stress for 30 minutes before measuring serum calcium, and in the second, fish were exposed to stress for 5 minutes and returned to normal conditions for 25 minutes before measuring serum calcium. Condit ion (K-value) and sexual development were noted for the fish. Serum calcium increased in all stressed fish, regardless of sex, but higher serum calcium values were observed in stressed mature females than in stressed males or stressed immature …

The Effects Of Adrenalectomy On The Onset Of Puberty In The Female Golden Hamster, Gina Micaletti

Master's Theses

No abstract provided.

Arthropod Species Diversity, Composition And Trophic Structure At The Soil Level Biotope Of Three Northeastern Illinois Prairie Remnants, With Botanical Characterization For Each Site, Dean George Stathakis

Master's Theses

No abstract provided.

Metabolism Of N⁶- Δ ²-Isopentenyladenine In Saccharomyces Cerevisiae, Kast Carol Anne Van

Master's Theses

No abstract provided.

Influences Of Captivity On Gorilla And Orang-Utan Behavior, Coquette Elliott

Master's Theses

No abstract provided.

Polymorphic Arrangement Of 5s Dna Orphons In Xenopus Laevis, Brenda A. Peculis

Master's Theses

No abstract provided.

An Electrophoretic Analysis Of The Genetic Relationship Between Etheostoma Nigrum And Etheostoma Olmstedi (Percidae: Etheostomatini) In The James River Drainage Of Virginia, John Stuart Prince Jr.

Master's Theses

Etheostoma nigrum Rafinesque 1820, the Johnny darter ranges from Alabama to the Hudson Bay and from Colorado east to the Atlantic slope in the James, Roanoke, Tar and Neuse Rivers. Etheostoma olmstedi Storer 1842, the tesselated darter, is restricted to the east coast in the Atlantic and Lake Ontario drainage. In the James and Roanoke River systems in Virginia E. nigrum occupies the piedmont and montane regions whereas E. olmstedi primarily inhabits the coastal plain. The relationship between the morphologically similar species of darters (subgenus Boleosoma) is controversial and has been investigated by several authors. Stone (1947), using multiple character …

Anatomy And Systematics Of Penthorum L., Melanie Lynn Haskins

Master's Theses

The genus Penthorum L. consists of two species of perennial herbs, P. sedoides of eastern North America and P. chinense of eastern Asia. Penthorum has long be.en considered intermediate between crassulaceae and Saxifragaceae. An anatomical study of both species was undertaken to contribute to a better understanding of the relationships of these plants. Prominent anatomical features of Penthorum include: an aerenchymatous cortex and closely-spaced collateral vascular bundles of stems; one-trace unilacunar nodes; brochidodromous venation, rosoid teeth bearing hydathodes, and anomocytic stomata of leaves; angular vessel elements with many-barred scalariform perforation plates and alternate to scattered intervascular pits; thin-walled non-septate fiber-tracheids; …

Atp Defendent Na+ Transport And The Characterization Of Na+ / Nh4+ Exchange In Basolateral Vesicles Of The Blue Crab, Callinectes Sapidus, Gill, Linda Ann Fuhrman

Master's Theses

ATP dependent Na⁺ transport was denonstrated in purified ba.solateral vesicles of the blue crab (Callinectes sapidus) gill. Active Na⁺ uptake was dependent upon the intravesicular presence of either K⁺ or NH; as a counterion. Final membrane preparations consist of inside-out basolateral vesicles, evidenced by intravesicular ouabain (1 rrM) and extravesicular vanadate (1 rnM) ²²Na ⁺ uptake inhibition. Na⁺/NH₄⁺exchange rates were investigated by detennining the NH; concentration in the recovered extravesicular nedium and by using the kinetic capabilities of a DU7 spectrophotareter. These purified basolateral membranes, rich in Na⁺,K^{+ …}

The Effects Of Stress On The Blood Calcium Level In The Male White Rat (Rattus Norvegicus), Howard Perry Cobb

Master's Theses

THE EFFECTS OF STRESS ON THE BLOOD CALCIUM LEVEL IN THE MALE WHITE RAT (Rattus norvegicus) by Howard Perry Cobb I I I was writ ten as part of the requirements for a Master of Science degree in Biology at the University of Richmond (May, 1985). The present experiment was designed to determine whether parathyroid hormone (PTH) can be considered a "stress" hormone. Parathyroidectomized (PX) male rats (160-200 g) were injected with 10, 20, or 30 USP units of PTH per 100 g body weight and subjected to confinement/UHF stress for a 1.5-h period. Serum calcium levels of these PX …