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Reactions Of Aqueous Chlorine In The Gastric Fluid Of The Rat, Michael Gary Nickelsen Apr 1988

Reactions Of Aqueous Chlorine In The Gastric Fluid Of The Rat, Michael Gary Nickelsen

Chemistry & Biochemistry Theses & Dissertations

Gastric fluid was recovered from Sprague-Dawley rats that had been fasted for 24 hr or 48 hr and administered 4 mL deionized water. The protein, carbohydrate and chloride ion content of the gastric fluid was determined.

When gastric fluid is chlorinated with radiolabeled chlorine to concentrations between 323 and 375 mg/L, analyzed by high performance chromatography followed by liquid scintillation counting, as much as 59% of the radiolabeled chlorine was associated with organic components of the gastric fluid.

Model studies with the aromatic amino acids and the protein pepsin showed the formation of chlorinated analogs. Two chlorinated amino acid derivatives …


The Relationship Between Multiple Health Factors, Demographics, And Body Weight, Glenda J. Potter Apr 1988

The Relationship Between Multiple Health Factors, Demographics, And Body Weight, Glenda J. Potter

Community & Environmental Health Theses & Dissertations

The purpose of this study was to test the relationship between regular aerobic exercise and body weight. It was the intent of this study to determine if a person who regularly exercises at either high or moderate levels can maintain their body weight at desired levels as specified by the Body Mass Index (BMI). The participants in this study were selected from hospital employees, class members of aerobic classes and/or adult walkers/joggers. There were 38 participants-- 13 males and 25 females.

A self administered questionnaire and a 3-day, 24-hour dietary log were identified to comprise the instrument as well as …


Faulkner: Misogynist Or Philogynist?, Imane Nejjar Apr 1988

Faulkner: Misogynist Or Philogynist?, Imane Nejjar

English Theses & Dissertations

No abstract.


Age And Growth Of The Tautog, Tautoga Onitis (Pisces: Labridae), From Lower Chesapeake Bay And Coastal Waters Of Virginia, E. Brian Hostetter Apr 1988

Age And Growth Of The Tautog, Tautoga Onitis (Pisces: Labridae), From Lower Chesapeake Bay And Coastal Waters Of Virginia, E. Brian Hostetter

Biological Sciences Theses & Dissertations

The tautog, Tautoga onitis (Pisces: Labridae), is rapidly gaining popularity in Virginia by anglers, spearfishermen and specialized commercial interests. In Virginia, tautog are seasonally abundant on hard bottom substrates in nearshore (ca. 2-10 m) habitats and inhabit offshore wrecks and reef areas (ca. 10-30 m) year round. Habitat restriction and slow growth of the species coupled with recent technological advances in marine electronics which simplify locating tautog populations by user groups may contribute to overexploitation of tautog within the region.

Tautog were collected over a two year period from the lower Chesapeake Bay and nearshore waters of the Atlantic Ocean …


Decomposition Of Roots In The Great Dismal Swamp, Edward G. Tupacz Apr 1988

Decomposition Of Roots In The Great Dismal Swamp, Edward G. Tupacz

Biological Sciences Theses & Dissertations

The decomposition rates of roots to a depth of 40 cm were estimated by two methods in four plant communities in the periodically flooded Great Dismal Swamp. Modified litter bags and a core method were simultaneously employed on three flooded sites and an unflooded mixed hardwood site. Reciprocal samples (litter from each of the other sites) were placed on each site to examine the effects of litter composition.

For the litter bags, the cedar and maple - gum sites displayed the lowest mean decay rate. However, reciprocal samples showed that roots from the cedar and mixed hardwood sites decayed the …


Effects Of Ethanol And Caffeine Administered Maternally On Neonatal Adrenocortical Function, Rhonda L. Mullins Rohlfing Apr 1988

Effects Of Ethanol And Caffeine Administered Maternally On Neonatal Adrenocortical Function, Rhonda L. Mullins Rohlfing

Biological Sciences Theses & Dissertations

Two investigations were conducted to determine the effects of maternally administered ethanol and caffeine on neonatal adrenocortical function. In the ethanol study, pregnant female rats were fed a liquid diet in which 35% of the sucrose calories were removed and replaced with ethanol. Dams in the caffeine study were injected with 25 mg/kg/day caffeine in saline solution. Within 24 hours of parturition, neonatal rats in both studies were sacrificed. The adrenal glands were incubated in vitro for one hour and media were analyzed for corticosterone content. Significant adrenal weight differences were found in both studies. The ethanol group pups were …


Laminin Receptors For Neurite Formation, H. K. Kleinman, Roy C. Ogle, F. B. Cannon, C. D. Little, T. M. Sweeney, L. Luckenbill-Edds Feb 1988

Laminin Receptors For Neurite Formation, H. K. Kleinman, Roy C. Ogle, F. B. Cannon, C. D. Little, T. M. Sweeney, L. Luckenbill-Edds

School of Medical Diagnostics & Translational Sciences Publications

Laminin, a basement membrane glycoprotein promotes both cell attachment and neurite outgrowth. Separate domains on laminin elicit these responses, suggesting that distinct receptors occur on the surface of cells. NG108-15 neuroblastoma-glioma cells rapidly extend long processes in the presence of laminin. We report here that 125I-labeled laminin specifically binds to these cells and to three membrane proteins of 67, 110, and 180 kDa. These proteins were isolated by affinity chromatography on laminin-Sepharose. The 67-kDa protein reacted with antibody to the previously characterized receptor for cell attachment to laminin. Antibodies to the 110-kDa and 180-kDa bands demonstrated that the 110-kDa protein …


Laureate, 1988, Old Dominion University Jan 1988

Laureate, 1988, Old Dominion University

Yearbooks

1988 yearbook of Old Dominion University


The Purification Of Ribosomal Rna Gene Chromatin From Physarum Polycephalum, Sally A. Amero, Roy C. Ogle, John L. Keating, Vicky L. Montoya, Wendy L. Murdoch, Robert M. Grainger Jan 1988

The Purification Of Ribosomal Rna Gene Chromatin From Physarum Polycephalum, Sally A. Amero, Roy C. Ogle, John L. Keating, Vicky L. Montoya, Wendy L. Murdoch, Robert M. Grainger

School of Medical Diagnostics & Translational Sciences Publications

We have undertaken the purification of ribosomal RNA gene (rDNA) chromatin from the slime mold Physarum polycephalum, in order to study its chromatin structure. In this organism rDNA exists in nucleoli as highly repeated minichromosomes, and one can obtain crude chromatin fractions highly enriched in rDNA from isolated nucleoli. We first developed a nucleolar isolation method utilizing polyamines as stabilization agents that results in a chromatin fraction containing far more protein than is obtained by the more commonly used divalent cation isolation methods. The latter method appears to result in extensive histone loss during chromatin isolations. Two methods were then …


Consequences Of Thymidine Catabolism For Estimates Of Bacterial Production: An Example From A Coastal Marine Sediment, Kevin R. Carman, Fred C. Dobbs, James B. Guckert Jan 1988

Consequences Of Thymidine Catabolism For Estimates Of Bacterial Production: An Example From A Coastal Marine Sediment, Kevin R. Carman, Fred C. Dobbs, James B. Guckert

OES Faculty Publications

Radioactively labeled thymidine (TdR) has been used extensively to measure bacterial production in aquatic environments, but critical assumptions of the TdR technique often have gone untested. In this study of a coastal marine sediment, the metabolic fate of methyl [3H]TdR and methyl [14C]TdR was at variance with the assumptions necessary for determining bacterial production. Only 2% of incorporated radioactivity was recovered in the DNA fraction of TCA-insoluble material following time-course incubations of l-300 min. At least the methyl group of TdR was extensively catabolized, as shown by copious production of 14C02. The temporal …


Host Selection In Subterranean Termites: Factors Affecting Choice (Isoptera: Rhinotermitidae), Deborah Ann Waller Jan 1988

Host Selection In Subterranean Termites: Factors Affecting Choice (Isoptera: Rhinotermitidae), Deborah Ann Waller

Biological Sciences Faculty Publications

The effects of block size and species on preference were examined for the subterranean termite Reticulitermes sp. (Rhinotermitidae) in choice and no-choice tests. Termites significantly preferred Douglas fir over Ponderosa pine and red oak, irrespective of block size. The less-preferred woods were eaten in large amounts in no-choice tests, and all three woods appeared to be favorable for the termites and their gut protozoans. In single species tests, termites ate significantly more from larger blocks of Douglas fir, but ate similar amounts from large and small blocks of Ponderosa Pine and red oak. These results suggest that several factors can …


The Effects Of Siltation On Recruitment Of Spiny Lobsters, Panulirus Argus, William F. Herrnkind, Mark J. Butler, Richard A. Tankersley Jan 1988

The Effects Of Siltation On Recruitment Of Spiny Lobsters, Panulirus Argus, William F. Herrnkind, Mark J. Butler, Richard A. Tankersley

Biological Sciences Faculty Publications

Fewer juvenile pinry lobsters were found in areas of the Florida Keys where their primary habitat was heavily silted as compared with similar, less silted habitat. Several hypotheses explaining this relationship were tested, and the time-to-metamorphosis was compared for settling pueruli within silted and nonsilted algae stands. Limited postlarval settlement and avoidance of silted algal habitats by juveniles, probably accounts for the paucity of young lobsters in heavily silted sites. In addition, although juvenile lobsters are nonselective predators, lower prey availability in silted algae probably promotes transciency which, in turn, causes increased mortality by predation while juveniles are exposed.


Variability Of Surface Pigment Concentrations In The South Atlantic Bight, Charles R. Mcclain, James A. Yoder, L. P. Atkinson, J. O. Blanton, T. N. Lee, J. J. Singer, Frank Muller-Karger Jan 1988

Variability Of Surface Pigment Concentrations In The South Atlantic Bight, Charles R. Mcclain, James A. Yoder, L. P. Atkinson, J. O. Blanton, T. N. Lee, J. J. Singer, Frank Muller-Karger

CCPO Publications

A 1‐year time sequence (November 1978 through October 1979) of surface pigment images from the South Atlantic Bight (SAB) was derived from the Nimbus 7 coastal zone color scanner. This data set is augmented with in situ observations of hydrographic parameters, freshwater discharge, sea level, coastal winds, and currents for the purpose of examining the coupling between physical processes and the spatial and temporal variability of the surface pigment fields. The SAB is divided into three regions: the east Florida shelf, the Georgia‐South Carolina shelf and the Carolina Capes. Six‐month "seasonal" mean pigment fields and time series of mean values …


Evaluation Of Possible Reproductively Mediated Character Displacement In The Crayfishes, Orconectes Rusticus And O. Sanbornii, Mark J. Butler Iv Jan 1988

Evaluation Of Possible Reproductively Mediated Character Displacement In The Crayfishes, Orconectes Rusticus And O. Sanbornii, Mark J. Butler Iv

Biological Sciences Faculty Publications

Orconectes rusticus is replacing several species of crayfishes in north-central and northeastern North America, including O. sanbornii in Ohio. Recent evidence suggests that the species replacements may be driven by asymmetrical reproductive success favoring O. rusticus. Nonetheless, some sympatric associations appear locally persistent. Because crayfish demonstrate size assortative mating and there is a disparity in the sizes of the species, further divergence in the sizes of the species in sympatry could enhance reproductive isolation, ultimately providing a mechanism for character displacement. To test this hypothesis the size differentials between crayfish collected from allopatric and sympatric populations in east-central Ohio …


A Simple Solid-Phase Electrophoretic Procedure For The Separation Of Plasmid Dna, Linda Ann Simurra Jan 1988

A Simple Solid-Phase Electrophoretic Procedure For The Separation Of Plasmid Dna, Linda Ann Simurra

Biological Sciences Theses & Dissertations

A method was developed for extraction of plasmid DNA from bacterial cells embedded in agarose blocks. Cell - containing blocks were treated with various lysing reagents and inserted into the wells of an agarose gel. Upon electrophoresis the plasmid DNA migrated out of the embedding block and into the gel leaving intact chromosomal DNA in the well. This method was tested with various organisms and found to be effective for plasmid isolation. In comparison to "traditional" procedures, this new method is less tedious since chemical separation of plasmids is not required prior to electrophoresis. Also, a higher yield of plasmid …


Preservation Of Atp In Hypersaline Environments, Bruce J. Tuovila, Fred C. Dobbs, Paul A. Larock, B. Z. Siegel Dec 1987

Preservation Of Atp In Hypersaline Environments, Bruce J. Tuovila, Fred C. Dobbs, Paul A. Larock, B. Z. Siegel

OES Faculty Publications

High concentrations of particulate ATP were found in the anoxic brines of the Orca Basin and East Flower Garden, Gulf of Mexico. Other measurements indicative of growth and respiration suggested that the microbial community in the brines was inactive, but somehow the ATP associated with the cells persisted. Conceivably, when cells growing just above the interface sank into the brine, the increased osmotic stress could elicit an osmoregulatory response resulting in increased ATP. It was also possible that hydrolytic enzymes were inactivated, resulting in the preservation of ATP. Experiments in which a culture of marine bacteria was suspended in menstrua …


Synthesis And Characterization Of N-Alkyl-Adenosine-5'-Diphosphates, Han-Ping Huang Oct 1987

Synthesis And Characterization Of N-Alkyl-Adenosine-5'-Diphosphates, Han-Ping Huang

Chemistry & Biochemistry Theses & Dissertations

n-Alkylphosphates and adenosine derivatives have been observed to be competitive inhibitors of coenzyme molecules in many NAD+ requiring enzymes. In earlier studies, adenosine derivatives such as AMP, ADP and ADP-ribose were found to be coenzyme competitive inhibitors of the Lactate Dehydrogenase catalyzed reaction. However, n-alkylphosphates, to the contrary, + were found to be noncompetitive inhibitors of NAD+.

Furthermore, it was observed previously in Dr. Yuan's laboratory that the effect of n-octylphosphate on the LDH catalyzed reaction was changed from noncompetitive to competitive in the presence of low concentration of AMP. Rossmann et al. reported that the binding …


Molting In The Mature Female Blue Crab, Callinectes Sapidus, Rathbun, Kirk J. Havens Oct 1987

Molting In The Mature Female Blue Crab, Callinectes Sapidus, Rathbun, Kirk J. Havens

OES Theses and Dissertations

The present study examines the hypothesis that mature female blue crabs, Callinectes sapidus, do not have a terminal anecdysis. Induced molting via eyestalk ablation, size frequency distributions and gonad and limb regeneration indices from field collected animals are used as indicators of potential post maturity molts.

Eyestalk ablation of mature females resulted in ecdysis approximately 51 days after ablation, indicating a physiological ability if mature females to complete ecdysis. Analysis of size frequency distributions indicates two distinct shifts from smaller to larger females, one in early spring and a second in early fall. While migration of larger females into …


Investigation Of Complex Formation By Oligomers Of Cytosine And Guanosine, Steven Roberts Davis Oct 1987

Investigation Of Complex Formation By Oligomers Of Cytosine And Guanosine, Steven Roberts Davis

Chemistry & Biochemistry Theses & Dissertations

Duplex formation between oligo(C:G) n where n=3 to 4 was shown not to occur under conditions favorable for duplex formation between poly G and poly C. Instead, a stable guano sine self-structure was found to form which a Tm of 50°C for (Gp)3 and 80°C for (Gp)4 at strand concentrations of 10-5M in 1M NaCl. Neither a duplex nor a self-structure formed in the absence of salt.

Oligomers of guanosine and cytosine were obtained by basic hydrolysis and separated according to chain length using DEAE Sephadex column chromatography. Separation of cytosine oligomers with chain lengths …


Phytoplankton Dynamics In The Very Low Salinity Region Of The James River Estuary, Virginia, U.S.A., Changho Moon Oct 1987

Phytoplankton Dynamics In The Very Low Salinity Region Of The James River Estuary, Virginia, U.S.A., Changho Moon

OES Theses and Dissertations

During summer and autumn discharge from the James River estuary, Virginia, was less than 120 m3sec-1. There was a peak phytoplankton biomass in the very low salinity region (defined as the location where surface salinity measured less than 0.5$ 0/00) and this peak represented five to ten times greater biomass than adjacent waters. The peak biomass occurred independent of the tidal state and the location of nutrient inputs. It disappeared during winter and spring, and nutrient limitation was not responsible for the low phytoplankton biomass, indicating there were physical, not chemical controlling factors.

The peak biomass …


Use Of Woody Vegetation By Beavers In Southeastern Virginia, John L. Echternach, Robert K. Rose Oct 1987

Use Of Woody Vegetation By Beavers In Southeastern Virginia, John L. Echternach, Robert K. Rose

Biological Sciences Faculty Publications

Nonbreeding and sometimes transient beavers, Castor canadensis, cut a variety of woody plants throughout the year during a 15-month study at three sites in southeastern Virginia. Ten species of trees were cut in proportions greater than would be expected according to their availabilities. Beavers heavily used viburnum, alder, ironwood, bayberry, tulip poplar, and dogwood. Winter food caches were constructed but were only lightly used.


Perceived Job Stress In Critical Care Nursing In A Military Setting, Jeannette Theriault Aug 1987

Perceived Job Stress In Critical Care Nursing In A Military Setting, Jeannette Theriault

Ellmer School of Nursing Theses & Dissertations

The purposes of this study. were: to explore job-related perceptions of stress in a group of military critical care nurses; and to determine if differences in anxiety and stress levels existed between nurses working in coronary care (CCCU) and medical/surgical intensive care (ICU) settings using the State/Trait Anxiety Inventory and the Questionnaire of Stressful Factors in Intensive Care. A free response question and a force-response checklist were also used to identify and rank work-related stressors. The sample of Navy nurses (n=105) consisted of 39 CCU nurses, 62 medical/surgical ICU nurses and 4 critical care supervisors. The results of the mailed …


Implications Of A Family Systems Orientation For Preventing Psychiatric Hospitalization, James Howard Bullock Jul 1987

Implications Of A Family Systems Orientation For Preventing Psychiatric Hospitalization, James Howard Bullock

Psychology Theses & Dissertations

The present study evaluated the implications of a family systems approach for preventing psychiatric hospitalization by comparing the behavior of field clinicians who professed a systems view versus clinicians who held more traditional nonsystems views. The focus of the investigation was the clinical assessments and decisions of 31 clinicians who worked at five Virginia public mental health centers as they prescreened (i.e., evaluated need for inpatient treatment) 171 candidates for hospitalization. Q-technique was employed to determine theoretical orientation.

It was hypothesized that clinicians who held a systems view would be more likely than nonsystems therapists to evaluate and attempt to …


Reactions Of Organic N-Chloramines In The Gastric Fluid Of The Rat, Kathryn E. Mazina Jul 1987

Reactions Of Organic N-Chloramines In The Gastric Fluid Of The Rat, Kathryn E. Mazina

Chemistry & Biochemistry Theses & Dissertations

Using chlorine as a drinking water disinfectant may have potential health effects due to its reactivity with organic amino nitrogen compounds found in the stomach. Organic N-chloramines have been shown to form in the stomachs of laboratory rats. The possible reactions of N-chloramines in the stomach fluid were examined in this study using a model radiolabeled N-chloramine. 36Cl-N-Chloropiperidine, was synthesized and purified to remove 36Cl-chloride. Stomach fluid was obtained from Sprague-Dawley rats which had been first fasted for 24 or 48 hours and then administered 3 mL of deionized water. Different concentrations of radiolabeled chloramine were reacted with …


Analysis Of Phytoplankton And Particle Variability At A Warm Core Ring/Shelf Break Front Using Flow Cytometry, Kimberly G. Davis Jul 1987

Analysis Of Phytoplankton And Particle Variability At A Warm Core Ring/Shelf Break Front Using Flow Cytometry, Kimberly G. Davis

OES Theses and Dissertations

Particle variability at a Gulf Stream warm core ring/ shelf break front on 09 Nay 1985 was analyzed. Single particle measurements of fluorescence, perpendicular light scatter, and volume were made using a FACS Analyzer flow cytometer. Advantages and disadvantages of at-sea use of the instrument are described. To evaluate the flow cytometry data, individual particle data were compared with bulk phytoplankton and particle measurements. Abundance and size distributions of fluorescent and non-fluorescent particles indicated a convergence zone at the front while upwelling was likely within the ring perimeter. Variability in fluorescence (approximating chlorophyll A) and cell biovolume exposed regions of …


Synthesis Of Potential Long Acting Calcium Channel Antagonists: A Study Of 1,4-Dihydropyridine Analogs, Thomas E. Christos Jul 1987

Synthesis Of Potential Long Acting Calcium Channel Antagonists: A Study Of 1,4-Dihydropyridine Analogs, Thomas E. Christos

Chemistry & Biochemistry Theses & Dissertations

An investigation was undertaken to synthesize and evaluate longer acting analogs to the antihypertensive agent nifedipine. Analogs that are capable of covalent bonding to the nifedipine receptor were considered. These compounds may show increased activity as they will remain at the receptor for a longer period of time.

During the course of this study, previously unreported and unexpected products were encountered and lead to a more intense examination of the Hantzsch synthesis. Of particular interest was the oxazolidine 25 which was a major component of the Hantzsch synthesis when ethanolamine was used instead of ammonium hydroxide. Also isolated during this …


A Taxonomic Survey Of The Family Gyrinidae (Coleoptera) Of The State Of Virginia, Jerrold R. Harris Jul 1987

A Taxonomic Survey Of The Family Gyrinidae (Coleoptera) Of The State Of Virginia, Jerrold R. Harris

Biological Sciences Theses & Dissertations

The aquatic insect fanua of Virginia is not very well known. This is especially true of the order Coleoptera. There are few taxonomic studies on the families of Coleoptera found within the state, and one of the least known is the family Gyrinidae. It is the intent of this study to determine what species of Gyrinidae are found within the state and where they are found. Collections of the beetles were made throughout the state from March to December.

Twenty-one species of Gyrinidae were identified in Virginia, nine species of Dineutus and 12 species of Gyrinus. The family is distributed …


A Comparison Of Potential Fishing Methods Associated With Fish Aggregating Devices Off The Northeast Coast Of Puerto Rico, Alan M. Friedlander Jul 1987

A Comparison Of Potential Fishing Methods Associated With Fish Aggregating Devices Off The Northeast Coast Of Puerto Rico, Alan M. Friedlander

OES Theses and Dissertations

Six fish aggregating devices (FADs) were deployed in June and monitored through December 1986. Emphasis was placed on trolling, live-bait handlining and longlining.

There was a significant difference (x2 = 7.815, pCoryphaena hippurus) which made up 64.2% of the catch.

Handlining at night around inshore buoys for one boat yielded 82.7 kg per trip. Pelagic fish comprised 83.9% of the catch, with the majority (81.4%) being kingfish (Scomberomorous cavalla). Catch rates were 50% higher and the species diversity much greater on the FADs versus control during experimental nightfishing, but the difference was not significant.

Longlining resulted in 3.4 …


An Annual Study Of Phytoplankton Composition And Associated Environmental Conditions Of Lake Trashmore, Virginia Beach, Virginia, Seba B. Sheavly Jul 1987

An Annual Study Of Phytoplankton Composition And Associated Environmental Conditions Of Lake Trashmore, Virginia Beach, Virginia, Seba B. Sheavly

Biological Sciences Theses & Dissertations

A 12 month study of Lake Trashmore was conducted on phytoplankton composition, inorganic nutrients and their seasonal associations. The dominant phytoplankton groups observed were diatoms, chlorophyceans and cyanobacteria. Phytoplankton assemblage patterns were coupled with pH, temperature, dissolved oxygen, nitrites and silicates. Diatoms dominated during periods of high nutrient concentrations, cooler temperatures and an unstable water column. Cyanobacteria forms dominated during periods of warmer temperatures, higher pH and decreased nitrogen and dissolved oxygen concentrations. A seasonal community shift occurred from cyanobacterial dominance to chlorophycean dominance when pH levels decreased. The lake is eutrophic based on indices of chlorophyll a concentrations, transparency …


The Geochemistry Of Selenium And Sulfur In A Coastal Salt Marsh, David Jay Velinsky Jul 1987

The Geochemistry Of Selenium And Sulfur In A Coastal Salt Marsh, David Jay Velinsky

OES Theses and Dissertations

Investigation of the various chemical forms of selenium and sulfur in sediments and pore waters can provide information about various oxidation/reduction processes. Five cores were obtained from the Great Marsh, from April 1985 to June 1986. Sampling times coincided with the seasonal redox cycle known to occur within the marsh system. Sediments were analyzed for various selenium and sulfur phases.

Iron monosulfides and elemental sulfur both display large seasonal changes in concentration and distribution with depth, indicating a coupling with redox conditions. In contrast, the depth distribution of greigite did not show appreciable changes with season. Pyrite underwent large concentration …