Life Sciences Commons^™

Determination Of Total And Unfilterable Plasma Aluminum In Uremic Patients, Theodore R. Delbridge

Chemistry & Biochemistry Theses & Dissertations

Aluminum accumulation in the soft tissues and bone of end stage renal failure patients has been described in the literature. In addition to aluminum normally encountered through ubiquitous sources, these patients are subject to exposures through the dialysate used for hemodialysis and through aluminum-containing phosphate binders. These increased exposures, associated with a decreased ability to excrete aluminum through the kidneys, lead to aluminum accumulation which may result in the onset of an encephalopathy syndrome and/or osteomalacic osteodystrophy. These complications may be very devastating.

Blood serum or plasma aluminum levels do not reflect the total body burden of aluminum. However, they …

Comparison Of An Improved Plankton Sampler To The Standard Conical Plankton Net, Ronald S. Schmidt

OES Theses and Dissertations

A comparison of field and tank tests between the standard conical plankton net and an improved version of a plankton sampler is presented. The improved sampler was shown to filter larger quantities of water than the standard net without having the filtration efficiency reduced below 85%. The improved sampler was also shown to capture an increased number of plankton per volume sampled, as a result of eliminating increased avoidance activity by zooplankton. It was not shown that. the improved sampler capture either larger maximum sizes of zooplankton or additional species.

Small Farmers' Cooperatives In Brazil, 1964-1984 Reasons For Success Or Failure, Henry H. Gerber

Graduate Program in International Studies Theses & Dissertations

This study is concerned with cooperative business enterprises of small farmers. The topic has been chosen because peasants' association in supply and marketing cooperatives is considered an essential element in rural development. The author's field experience leads him to agree in principle with this assumption. But, as exemplified by Brazil, a variety of factors (ecological, sociohistorical, legal, economic and so forth) may hinder or help the inception and survival of cooperatives.

Thus, if a government aims at integrating the small producer into the national economy as supplier and consumer (as in Brazil), measures to implement t~is policy must not be …

A Biochemical And Genetic Analysis Of The American Shad Alosa Sapidissima Migrating Into The Chesapeake Bay, Edward Norbert Sismour

Biological Sciences Theses & Dissertations

Seven enzymes extracted from heart and liver tissues of American shad Alosa sapidissima captured during migrations into the Chesapeake Bay and Nansemond River were electrophoretically surveyed. Malate dehydrogenase and nonspecific esterase displayed polymorphic loci. The esterase polymorphism was used as a biochemical genetic marker to analyze the shad migration through the southern Chesapeake Bay. The genetic composition of the shad migration changed significantly over time indicating that this migration is probably composed of multiple, genetically divergent spawning populations. Results of this study are subject to differing interpretations. Observed temporal heterogeneity may result from separation of northern and James River stocks …

Acetylcholinesterase In The Neonatal Rat Brain: The Effects Of Prenatal Ethanol Exposure, Linda M. Boland

Biological Sciences Theses & Dissertations

Acetylcholinesterase (AChE) activity in the neonatal rat brain was determined by histochemical localization and quantitative biochemical analysis. AChE-positive perikarya were concentrated in the neostriatum, globus pallidus, medial habenular nucleus, amygdaloid complex, various hypothalamic nuclei, gigantocellular and paragigantocellular reticular nuclei, raphe nuclei, locus coeruleus, and motor nuclei of cranial nerves III-VII and IX-XII. Some areas stained differently or not at all when compared with the adult rat brain. The effects of prenatal ethanol exposure on regional AChE activity were assessed by comparing enzyme levels in offspring exposed via maternal consumption of a liquid diet containing 35 percent ethanol derived calories. This …

The Relationship Between Habitat Structure And Small Mammal Communities In Southeastern Virginia And Northeastern North Carolina, Roger Keith Everton

Biological Sciences Theses & Dissertations

A variety of terrestrial habitats was pitfall trapped in the vicinity of the Great Dismal Swamp of eastern Virginia and North Carolina to evaluate the small mammal community within the region. Habitat variables were measured at the end of the growing season on 21 0.25 ha grids. Four multivariate tests were used to examine the small mammal communities, their relationship with habitat structure, and the role of habitat selection in community structure.

Cluster and ordination analysis revealed the existence of two distinct associations of small mammals, and their habitat types, within the region. The small mammal associations were interpreted as …

The Distribution Of Ceratia Over The Mid-Atlantic Bight, Paul V. Zimba

Biological Sciences Theses & Dissertations

The distribution and concentration of Ceratium species, between Cape Hatteras, North Carolina and Long Island, New York ls discussed in relation to specific physical factors and the development of a phytoplankton bloom. The progression of high Ceratium counts Is discussed for the Bight areas of New York, Delaware, and the Chesapeake Bay (April through June). The concentration of Ceratium species declined after June, with highest concentrations along the New York and Delaware coast-lines. Coastal regions (less than 12 km from shore) were associated with high concentrations of several species. Path and regression analysis were used to relate physical factors and …

The Synthesis And Evaluation Of A New Analog Of Phencyclidine (Pcp), William H. Johnson Jr.

Chemistry & Biochemistry Theses & Dissertations

Based on an interpretation of the literature of phencyclidine (PCP) together with an examination of the relevant models or prototype structures, this research has attempted to design and synthesize a rigid analog of the phencyclidine structure. The parent ring systems suggested for this study were the 1-arnino and 2-arninornethyltetralins, 10 and, 12.

Several organic compounds, based on this design, have been prepared by classical examples of reductive alkylation reactions of the corresponding 2-hydroxyciethylene-1-tetralones, 11, and by the condensation and subsequent reductive alkylation of the 1-arninotetralin, 9. These arninomethyltetralones, 28, 29 and 30, together with an example of a substituted 1-arninotetralin, …

Discriminative Insulin Antagonism Of Stimulatory Effects Of Various Camp Analogs On Adipocyte Lipolysis And Hepatocyte Glycogenolysis, Stephen J. Beebe, J. Bruce Redmon, Peter F. Blackmore, Jackie D. Corbin

Bioelectrics Publications

Although insulin effectively blocked hormone-stimulated glycerol output in adipocytes or phosphorylase activation in hepatocytes, the inhibitory effect of insulin on cAMP analog-stimulated cells depended on the cAMP analog used. Of the 20 analogs tested in adipocytes and 13 tested in hepatocytes, the effects of about half of them were effectively blocked by insulin, whereas the effects of many of them were not inhibited at all. In order to approach the explanation for this discriminative insulin action, the inhibitory effects of insulin on the responses to the analogs in the intact cells were correlated with the in vitro cAMP analog specificity …

Camp-Dependent Protein Kinase Activation Lowers Hepatocyte Camp, Jackie D. Corbin, Stephen J. Beebe, Peter F. Blackmore

Bioelectrics Publications

Rat hepatocyte protein kinase was activated by incubating the cells with various cAMP analogs. Boiled extracts were then prepared and Sephadex G-25 chromatography was carried out. The G-25 procedure separated the analogs from cAMP since the resin had the unexpected property of binding cyclic nucleotides with differing affinities. Separation was necessary because the analogs would otherwise interfere with the sensitive protein kinase activation method developed for assay of cAMP. The cAMP analogs, but not 5'-AMP, lowered basal cAMP by 50-70%. The effect was rapid, analog concentration-dependent, and occurred parallel with phosphorylase activation, suggesting that the cAMP analogs act through cAMP-dependent …

Microbial Manganese Reduction By Enrichment Cultures From Coastal Marine Sediments, David J. Burdige, Kenneth H. Nealson

OES Faculty Publications

Manganese reduction was catalyzed by enrichment cultures of anaerobic bacteria obtained from coastal marine sediments. In the absence of oxygen, these enrichment cultures reduced manganates when grown on either lactate, succinate, or acetate in both sulfate-free and sulfate-containing artificial seawaters. Sodium azide as well as oxygen completely inhibited microbial manganese reduction by these enrichment cultures, whereas molybdate had no effect on them. The addition of nitrate to the medium slightly decreased the rate of Mn²⁺ production by these enrichment cultures. These findings are consistent with the hypothesis that the manganese-reducing organisms in these enrichment cultures use manganates as terminal …

Economics Of The Pacific Whiting, Merluccius Productus, Fishery, Eric Anderson

Economics Faculty Publications

(First paragraph) Interest in the economics of Pacific whiting, Merluccius productus, production and consumption has been simulated in recent years by expanding U.S. participation in the fishery formerly dominated by foreign fishing and processing. This has raised several questions within the U.S. fishing industry: 1) Will it be profitable for additional U.S. fisherman and processors to enter the fishery? 2) What configuration will the U.S. Pacific whiting industry take? and 3) What will be the nature of markets for Pacific whiting products? This paper summarizes the conclusions of several reports and studies which bear on these questions.

Community Ecology, Robert K. Rose, Elmer C. Birney

Biological Sciences Faculty Publications

COMMUNITIES with Microtus tend to be structurally simple, usually grasslands or tundra, and to have no more than two species of Microtus and rarely more than six species of small mammals. Microtus often dominates both numerically and in total small mammal biomass, especially at higher latitudes. The small mammal community is most influenced by Microtus through its fluctuations in density, and thus also in biomass, by its relatively high level of diurnal activity, and by its year-round activity. Other species of small mammals may be adversely affected because Microtus usually is larger and behaviorally dominant and also because the mere …