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The Effect Of Dredging On The Plant Community Of A Missouri-River Floodplain Wetland., Lisa Ann Peterson

Student Work

A plant community gradient, consisting of Open-water, bulrush, Grass, and Forest Zones, was evaluated both before (1995) and one-year after (1997) restoration-dredging of a wetland along the Missouri River in east-central Nebraska. Species diversity declined significantly (P ≥ 0.05) in both the Bulrush and Grass Zones (-24 and -30 species) but not elsewhere. The Open-water Zone, which increased the most with dredging (+40 meters), was dominated by duckweed (Lemna minor) (53% canopy cover in 1995 and 45% in 1997) and watermeal (Wolddia columbiana) (53% and 61%) both before and after dredging. Coontail (Ceratophylum demersum) increased significantly (7% to 25%). The …

Standardization Of An Immunoassay For The Detection Of Antibodies To B2 Glycoprotein-I, Eric N. Erickson Jr.

Seton Hall University Dissertations and Theses (ETDs)

Antiphospholipid Syndrome (APS) is an evolving autoimmune disease with numerous clinical manifestations. APS occurs in two forms: Primary Antiphospholipid Syndrome (PAPS) and secondarily in association with other autoimmune disorders such as Systemic Lupus Erythematosis (SLE). In the brief period since its discovery as a cofactor for anticardiolipin antibodies, p1-glycoprotein I (�GPI; apolipoprotein H) has been recognized as the autoantigen in the absence of anionic phospholipid when appropriately presented to human autoantibodies. Recent studies suggest that this presentation requires the surface-dependent unmasking of a cryptic epitope. Immunoassays of autoantibodies directed against p1GPI, developed through the application of suitable polymeric matrices, may …

Regulation Of The Gbn-1 Transcript During Vegetative Growth And Macrocyst Development In Dictyostelium., Jodi R. Hall

Student Work

A transcript corresponding to the gene gbn-1 has been found in Dictyostelium mucoroides during vegetative growth and microcyst development. The nucleotide and amino acid sequence is known, and the amino acid sequence was found to be 65% similar and 50% identical to a hemoglobin protein found in the bacterium Vitreoscilla. The purpose of the study was to further characterize the gbn-1 gene activated during development of microcysts. The transcript was found in Dictostelium cells during the vegetative stage and during microcyst development. Quantitative results, using 18S rRNA as an internal control, on the microcyst cells. Later developing cells still produced …

The Reproductive Biology And Edaphic Characteristics Of A Rare, Gynodioecious Saxifage: Saxifraga Bryophora Var. Tobiasiae (Saxifragaceae), Kimberly Pierson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I examined the reproductive biology and general ecology of Saxifraga bryophora var. tobiasiae, a rare saxifrage endemic to the West Salmon River Mountains of central Idaho. Saxifraga bryophora var. tobiasiae combines asexual reproduction via bulbils with a sexual mixed-mating system. Flower production occurred in 1996 only, whereas bulbil production occurred in 1995, 1996, and 1997. Bulbil production precedes floral bud formation and is the dominant form of reproduction. When flowering occurs, outcrossing is promoted by protandry and the gynodioecious mating system found in all populations. No autogamous or agamospermous seed set was observed in either female or hermaphrodite flowers, …

Effects Of Low-Oxygen Atmosphere On The Growth And Development Of Arabidopsis Thaliana (L.) Heynh., Katrina Maria Ramonell

LSU Historical Dissertations and Theses

Interest in the improvement of crop productivity through repression of photorespiration led to experimental growth of plants in low O2 and the surprising finding that reproduction is inhibited under these conditions. Using Arabidopsis thaliana (L.) Heynh. cv. Columbia, studies were undertaken to understand the mechanism behind oxygen control of plant development. The hypothesis that developmental changes observed in low O 2 are due to repression of the plant hormones ethylene and brassinolide (which require O2 for biosynthesis) was tested. Arabidopsis was grown for 35 days in Sun bags in one of five altered O 2 atmospheres (210, 160, 100, 50, …

Epidemiology Of Anthrax In The Kruger National Park, South Africa: Genetic Diversity And Environment., Kimothy Lyn Smith

LSU Historical Dissertations and Theses

The Kruger National Park, (KNP), in the Republic of South Africa, provides a unique opportunity to investigate interesting and unresolved aspects of the epidemiology of the disease anthrax. Anthrax is a disease of primarily mammals caused by the Gram-positive, rod-shaped, spore-forming bacteria Bacillus anthracis. Beyond it's great historical significance anthrax is clearly important in the world today. From a rich legacy of empirical investigations and observations in the form of ecological and epidemiological studies conducted around the world this work endeavors to distill and extract the essence of what biotic and abiotic factors of environment might be causally associated with …

Community Structure And The Effects Of Experimental Fires On Hardwood Shrub Species In Southeastern Longleaf Pine Savannas., Paul Boguslaw Drewa

LSU Historical Dissertations and Theses

The main objective of this dissertation is to describe and examine how altering fire regimes in southeastern longleaf pine savannas may affect the abundances and distributions of indigenous plant species. In chapter one, I investigate whether herbs, compared to shrubs, have greater utility in delineating communities along elevation gradients of several meters in longleaf pine savannas. Herbaceous and shrub abundance data were analyzed separately for areas in Louisiana and Florida using cluster analysis and ordination. In Louisiana, three plant communities were sharply delineated and strongly correlated with gradients in elevation, surface soil moisture, and other surface soil properties. Herbaceous species …

Capability Of Recombinant Insect Viruses For Environmental Persistence And Transport., Yihua Lee

LSU Historical Dissertations and Theses

Wild-type and recombinant nucleopolyhedroviruses (NPVs) were compared with respect to their capability to produce epizootics in Trichoplusis ni (Hubner) larvae infesting collards in a greenhouse microcosm. Viruses tested were variants of Autographa californica (Speyer) NPV (AcNPV): wild-type virus (AcNPV.WT), AcNPV expressing a scorpion toxin (AcNPV.AaIT), and AcNPV expressing juvenile hormone esterase (AcJHE.SG). Epizootics of AcNPV.WT lasted 8 weeks after a single viral release in the replicated, greenhouse micro-plots. AcJHE.SG epizootics also lasted 8 weeks after viral release, but this virus and AcNPV.AaIT were both out-competed by AcNPV.WT. AcNPV.AaIT was no longer detected in the T. ni population by the fourth …

Evolution Of Pycnogonid Life History Traits, Eric Carl Lovely

Doctoral Dissertations

The Pycnogonida is a class of arthropods with interesting life histories. Pycnogonids prey on hydroids and some invade hydranths while larvae. Males brood the eggs and larvae hatch as protonymphons. Questions relating to the evolution of life history characteristics were addressed. Evolutionary relationships were poorly understood. It was necessary to determine the relationships within the Pycnogonida and compared to other arthropods.

Twenty-four morphological characters were coded for twenty-three pycnogonid genera and one fossil ancestor, Palaeoisopus problematicus. A branch and bound analysis resulted in fifteen most parsimonious trees. The Nymphonidae were found to be basal. The Ammotheidae were paraphyletic and led …

The Effect Of Physical And Biological Site Characteristics On The Survival And Expansion Of Transplanted Eelgrass (Zostera Marina L), Ryan Clark Davis

Doctoral Dissertations

Eelgrass (Zostera marina L.) was transplanted at seven sites along the New Hampshire side of the Piscataqua River in 1993 and 1994. The eelgrass transplanting was one component of the New Hampshire Port Authority Mitigation Project, designed to mitigate for impacts to natural resources associated with the expansion of the port facility. Over 2.5 hectares of eelgrass were transplanted using a newly developed transplanting technique, the horizontal rhizome method, and ultimately created eelgrass habitat at several sites. However, transplants did not survive at any of the intertidal areas planted and were greatly reduced at several subtidal sites. The intertidal transplants …

Effects Of Intralaminar Thalamic Nuclei, Prefrontal Cortical, And Hippocampal Lesions On A Seven-Choice Serial Reaction Time Task, Joshua Alan Burk

Doctoral Dissertations

Slow response speed has been associated with several neuropsychological disorders including Korsakoff's disease. The ability to respond to brief stimuli can be tested to assess whether slow response speed is due to slow stimulus processing. A seven choice serial reaction time task was developed to test the ability to respond to brief stimuli. Distractibility and stimulus discriminability were manipulated to challenge performance and cues were presented to enhance performance. In Experiment 1, six unlesioned rats were tested on this task. As expected, significant deficits were found when (1) stimulus duration was decreased, (2) bright distractor light was briefly presented, (3) …

Isolation And Characterization Of A Caenorhabditis Elegans Src Loss-Of-Function Allele Using Reverse Genetics, Jennifer Dignan Hogan

Doctoral Dissertations

The vertebrate proto-oncogene Src is a protein-tyrosine kinase that has been implicated as a component of receptor-mediated signal transduction pathways important for cell growth and differentiation. Consistent with this notion, overexpression or activation of Src by mutation induces neoplastic transformation in cell culture, leads to tumorigenesis in laboratory animals, and has been observed in a number of human tumors. Despite years of intensive investigation, neither its role in oncogenesis nor its normal, biological role is understood.

To diminish the issue of redundancy that has complicated analysis of Src function in vertebrates and Drosophila, I have chosen to study Src function …

The Role Of Cytokines In The Pathogenesis Of Experimental Legionella Pneumophila Infections, Corinna Mary Krinos

Doctoral Dissertations

Legionnaires' disease is an acute lobar pneumonia caused, primarily by the facultative intracellular pathogen Legionella pneumophila. This organism when inhaled by humans descends into the lower respiratory tract and parasitizes alveolar macrophages. L. pneumophila adhered to U-937 cells, A549 cells and peritoneal macrophages from A/J mice in an opsonin-independent fashion. Following attachment, the organism penetrated the cell membrane, replicated within these cells eventually inducing lysis. To better define the adhesion of L. pneumophila to host cells, an E. coli clone (LP 116), expressing the 25 kDa major outer membrane protein (MOMP) of L. pneumophila was used in binding studies. This …

The Long-Term Effects Of Disturbance On Nitrogen Cycling And Loss In The White Mountains, New Hampshire, Christine Lynn Goodale

Doctoral Dissertations

Theories of nitrogen retention suggest that N cycling and loss should increase with ecosystem successional age and with chronic N deposition over time (N saturation). These factors both affect northeastern U.S. forests, most of which receive elevated rates of N deposition and have experienced past disturbances by wind, logging, fire, or agriculture. This work examined the long-term (80--110 year) effects of land-use history on nitrogen cycling and loss in the White Mountains, New Hampshire. Historical land-use maps were used to identify a network of watersheds and plots containing burned, logged, or old-growth forests. Nitrate-N fluxes from old-growth watersheds exceeded those …

Behavioral And Physiological Responses Of The Lobster, Homarus Americanus, To Temperature: A New Synthesis, Steven Harold Jury

Doctoral Dissertations

Temperature has a pervasive influence on lobster behavior, physiology and ecology and affects their subsequent distribution in thermally variable habitats such as estuaries and coastal areas. A multidisciplinary approach, including field and laboratory studies, was used to show: (1) that lobsters sense temperature with warm and cool thresholds as small as 0.1--0.2°C; (2) the relationship between temperature and activity is not linear, but instead switches between a high activity level in warmer months (10--20°C) and a lower level in colder months (<10°C) with transition periods in the spring and fall; (3) Parallel studies in the lab and field show that daily levels of activity are not greatly influenced by small temperature variations (i.e. tidally induced changes of 14°C), but activity levels are significantly higher in the field (249 +/- 55.1 m/d) than in the laboratory (88 +/- 12.0 m/d); (4) lobsters prefer a narrow range of temperatures over others available in a thermal gradient and avoid temperatures >23.5 +/- 0.4°C, suggesting that they behaviorally thermoregulate. While this preferred temperature shifts seasonally, the final preferred temperature …

Controls On Spatial And Temporal Variability In Nitrous Oxide Fluxes Across A Tropical Rainforest Ecosystem In The Luquillo Experimental Forest, Puerto Rico, Claire Patricia Mcswiney

Doctoral Dissertations

Nitrous oxide (N2O) is a trace gas that contributes to the greenhouse effect and participates in the reactions that destroy stratospheric ozone. Soil microbial processes are significant producers of this trace gas, particularly in tropical areas, which are considered major sources in the global N2O budget. Nitrous oxide fluxes to the atmosphere are variable in space and time. In this study, spatial and temporal variability in surface N2O fluxes were assessed as well as the major environmental controls on N2O production for a tropical rainforest watershed in northeastern Puerto Rico. A static chamber technique was used to assess surface fluxes …

Functional Characterization Of The Ccr4-Not Transcriptional Regulatory Complex, Vasudeo Badarinarayana

Doctoral Dissertations

The CCR4-NOT transcriptional regulatory complex affects expression of a number of genes both positively and negatively. This study demonstrates that the CCR4-NOT complex functionally and physically interacts with TBP and TAFs. Firstly, mutations in CCR4, NOT4, and NOT5 suppressed the his4-912 delta insertion by a mechanism similar to that observed for the defective TBP allele spt15-122. This mechanism appeared to involve stabilization of TBP binding to a specific non-consensus TATA sequence, CATAAA, in the his4-912 delta element. Secondly, using modified HIS3 promoter derivatives containing specific mutations within the TATA sequence, it was found that the NOT proteins were general repressors …

The Mut-2 Mutator Of Caenorhabditis Elegans, Kathrine Queta Flint Boese

Doctoral Dissertations

The mut-2 mutator plays multiple regulatory roles in the germ line of C. elegans. In addition to regulating germ line transposition of at least four distinct transposon families (Tc1, Tc3, Tc4 and Tc5) mut-2 is implicated in chromosome segregation. Animals that harbor the mut-2 mutator produce broods with a higher incidence of males phenotype (Him) as a result of an increase in X chromosome non-disjunction during meiosis.

Using the Him phenotype conferred by mut-2(r459), I mapped the gene to the dpy-14 sem-4 interval on LGI. However, efforts to identify a molecular clone of the gene were hampered because the available …

The Development Of Rna Probe And Rt-Pcr Assays For The Detection Of Enteroviruses In Sludge, Amy Elisabeth Moore

Doctoral Dissertations

Many wastewater treatment plants generate more sludge than can be disposed of by conventional means. The United States Environmental Protection Agency (USEPA) has encouraged communities to dispose of sludge by land application. Sludge may contain enteric viruses that are known to survive for long periods of time in sludge-amended soil and can travel great distances, potentially contaminating surface and ground water.

Standard cell culture methods for the detection of enteric viruses are costly and results are not obtained for 30 or more days. The development of methods that provide results more quickly and with lower cost are needed.

A 32P …

Viability And Spatial Assessment Of Ecological Communities In The Northern Appalachian Ecoregion, Mark Gustav Anderson

Doctoral Dissertations

My objective was to design a conservation reserve system that included multiple viable examples of all ecological community types within one specific ecoregion---the Northern Appalachians. I developed and defined the boundaries of the ecoregion, constructed a comprehensive list of the ecological communities and determined their scale of occurrence and distribution patterns. I also assessed the types and distributions of biophysical features within the ecoregion and developed a hierarchical scheme to partition the region into biophysical subregions. Subsequently, I assessed 1500 occurrences of ecological communities in the region compiled from state Natural Heritage databases and an analysis of roadless areas. Each …

Influence Of Environment And Genotype On The Expression Of Host Plant Resistance In Sweet Potato To The Sweet Potato Weevil, Cylas Formicarius (Fab.)., Lixin Mao

LSU Historical Dissertations and Theses

Field and laboratory experiments were conducted to study the influence of environment and genotype on the expression of sweetpotato resistance to the sweetpotato weevil (SPW), Cylas formicarius (Fab.). Roots of four genotypes ("W-244", "W-250", "Beauregard", "Centennial") were evaluated for SPW feeding and oviposition at three different storage times. Roots from Louisiana, South Carolina and Mississippi were also evaluated. Genotype had a significant effect on feeding and oviposition. Storage time and production sites appeared to affect resistance expression; the outcomes depend on the genotypes. The effect of nitrogen on sweetpotato resistance to SPW was studied. Four genotypes were grown in the …

Characterization Of A Simian Hemorrhagic Fever Virus Large Envelope Glycoprotein Gene And Its Product., Xiaochun Wang

LSU Historical Dissertations and Theses

The goal of this project was to determine the genome organization, replication strategy and identification of the large envelope glycoprotein (GL) gene of simian hemorrhagic fever virus (SHFV). This virus is the fourth member of the new virus family Arteriviridae. The 3' end of the RNA genome from the prototype isolate of SHFV was cloned and sequenced. This 6,314 nucleotide (nt) sequence consisted of nine complete overlapping open reading frame (ORFs 2, 2a, 3, 4, 5, 6, 7, 8, and 9). At the 5' end of this sequence is a partial ORF, ORF 1b, and the 3' end is a …

The Effects Of Anoxia And Temperature On The Development And Survivorship Of Hexagenia (Ephemeroptera: Ephemeridae) Embryos, And Implications For Western Lake Erie Populations., Jocelyn. Gerlofsma

Electronic Theses and Dissertations

Benthic Hexagenia embryos can be exposed to anoxic hypolimnetic water or can become buried in the sediment. In western Lake Erie, periodic anoxia resulting from transient stratification has eradicated Hexagenia populations. The ability of embryos to survive anoxia and hatch when normoxic conditions return would allow the population to recover after an anoxic event. I studied the survivorship and development of Hexagenia embryos at various developmental stages maintained in anoxic conditions for different time periods, at different temperatures. In 1996, Hexagenia nymphs were absent from several regions in western Lake Erie. I collected sediment cores from two such areas and …

Time Modelled As An Explicit Feature To Quantify Habitat Quality And Preference Of Chinook Salmon (Oncorhynchus Tshawyscha) In Western Lake Ontario At Two Time Scales: The Relative Importance Of Environmental Conditions And Some Implications., Denis. Roy

Electronic Theses and Dissertations

I used a novel, stationary hydroacoustic sampling technique to assess the temporal variation of Lake Ontario's ability to support chinook salmon (Oncorhynchus tshawyscha) habitat at two time scales. Hydroacoustics provides a highly effective, non-obtrusive means of sampling fish distributions within the pelagic environment, at very high temporal resolution. These data, along with more conventional measures of water quality (temperature profiles), allowed me to develop and apply a temporally explicit modelling framework which quantified, and described changes in, chinook habitat quality over time. I then examined actual chinook distribution collected acoustically to quantify chinook salmon habitat preference at both the seasonal …

Immunological Studies On Staphylococcal Alpha Toxin And Its Fragment (Staphylococcus Aureus)., Maria. Sawicki

Electronic Theses and Dissertations

The growing prevalence of antibiotic resistant Staphylococcus aureus strains, an important community acquired and nosocomial pathogen for compromised hosts, threatens the effectiveness of current strategies and demonstrates the need for other means of control and prevention. Designing vaccines against bacterial toxins is a challenge---a protective immune response must be induced in the absence of toxic biological activity. Previous development of anti-toxic immunity involved indiscriminate chemical or proteolytic inactivation of alpha toxin, a major pathogenicity factor of Staphylococcus aureus. In this study we used isoelectric focusing to isolate the 28 kD naturally occurring fragment of alpha toxin that was the product …

Molecular Genetics And Functions Of Herpes Simplex Virus Type 1 (Hsv-1) Glycoprotein K (Gk) In The Morphogenesis Of Infectious Virion Particles., Timothy Paul Foster

LSU Historical Dissertations and Theses

Herpes simplex virus type 1 (HSV-1) specifies at least 11 glycoproteins that are expressed in infected cells and in virions. HSV-1 enters into cells via fusion of the viral envelope with cellular membranes and can spread to adjacent cells via fusion of cellular membranes. Glycoproteins gB, gD, gH, and gL are known to be essential for virus entry, virus spread, and virus induced cell-to-cell fusion. The majority of spontaneous single amino acid changes that cause extensive cell fusion map within the UL53 gene encoding glycoprotein K (gK); however, the role of gK in virus entry and virus egress had not …

Null Codon-Based Models Of Synonymous And Nonsynonymous Substitution From A Phylogenetic Perspective., David A. Mcclellan

LSU Historical Dissertations and Theses

This dissertation focuses on the relationship between codon composition and the molecular evolution of protein-coding DNA sequences. Chapter 1 emphasizes the role of codon structure in determining patterns of nucleotide substitution, as well as the influence codon composition has on the evolution of the structure and function of the protein. The overall purpose of Chapter 1 is to establish the need to study molecular evolution at the codon level. In Chapter 2, the codon-degeneracy model (CDM) of molecular evolution is constructed. This model considers codon structure in terms of patterns of nucleotide site degeneracy. It allows the prediction of patterns …

Spatial Modeling Of Coastal Landscapes: Methodological And Scientific Applications., Mary Louise White

LSU Historical Dissertations and Theses

A number of issues related to landscape scale ecological modeling of the wetlands of southern Louisiana are examined in this study. First, using geostatistical methods, a new contour map of the wetland habitats in the Terrebonne basin of southern Louisiana is constructed from data collected in 1994. This map is proposed as the best field verified habitat map of the Terrebonne basin and contains statistical confidence intervals associated with the habitat contours. Second, the problem of how to evaluate the success of a landscape model prediction is investigated. The multiple resolution goodness of fit parameter Ft(k) is evaluated in detail …

Effects Of Fluctuating Salinity, Nutritional State, And Temperature On Leptasterias Spp. From Little Port Walter, Alaska., Jeffrey William Tamplin

LSU Historical Dissertations and Theses

The effects of fluctuating salinity, nutritional state, and temperature on activity, oxygen consumption, feeding, and growth rates were analyzed on seasonally collected Leptasterias spp. (Echinodermata: Asteroidea) from Little Port Walter, AK. Leptasterias aspera and L. epichlora were collected on June 10, 1994, divided into size groups, and perivisceral fluid osmolality was measured every three hours during a 12 h 30-10-30‰S fluctuating cycle. The perivisceral fluid osmolality of larger individuals fluctuated less than that of smaller sea stars. The perivisceral fluid osmolality of small and large Leptasterias spp. closely tracks the ambient water osmolality during tidal cycles. Leptasterias spp. were collected …

Production Of L-(+) Lactic Acid From Blackstrap Molasses By Lactobacillus Casei Subspecies Rhamnosus Atcc 11443., Narumol Thongwai

LSU Historical Dissertations and Theses

Lactobacillus casei subspecies rhamnosus grew on non-supplemented blackstrap molasses. The bacteria grew best at the optimal temperature of 40 +/- 2°C, and at pH 5.5. Addition of yeast extract to molasses shortened the lag phase and increased cell mass. In batch fermentations without pH control, the highest ratio of lactic acid produced to cell mass was 12 from non-supplemented molasses. For pH controlled batch fermentations, the ratio's of lactic acid produced/cell mass were 81, 79, 51 and 31 for 0, 0.2, 0.4 and 0.8% yeast extract supplementation, respectively. Non-supplemented molasses, 8% Brix, produced 28 +/- 2 g/l of lactic acid …