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Effect Of Harvest And Effective Population Size On Genetic Diversity In A Striped Bass Population, Marilyn Diaz, David S. Wethey, James Bulak, Bert Ely

Faculty Publications

A major factor that contributes to loss of genetic variation in natural populations is a small effective population size. In species with a complex life history that involves overlapping generations and delayed maturity, the impact of infrequent annual reproductive bottlenecks is likely to be small because effective population size is defined by the number of individuals contributing to a generation and not to a single year-class. The striped bass Morone saxatilis is a longlived species with overlapping generations and age structure, whose recreational and commercial importance has made it a target of intense harvest.We analyzed allele frequency fluctuation among juvenile …

Abstracts Of Papers Presented At The Seventy-Eight Annual Meeting, Virginia Academy Of Science, May 23-26, 2000, Radford University, Radford, Va

Virginia Journal of Science

This document is a list of the abstracts of papers presented at the seventy-eighth meeting of the Virginia Academy of Science that took place at Radford University on May 23 through the 26th, 2000.

Vegetation And Soil Relationships Of Interdunal Depressions In The Nebraska Sandhills Prairie., Danica Marie Kochis-Belleque

Student Work

Vegetation and soils of interdunal depressions were compared to those of adjacent north-facing slopes that represent the upland matrix of the Nebraska Sandhills Prairie. Data from canopy cover and biomass show interdunal depressions to be more variable in species composition but significantly lower in diversity than north-facing slopes (H’ = 1.294 and 1.451, respectively). Significant differences (P < 0.05) were observed for total plant cover (95% depression, 87% slope), grass cover (80% and 69%), total biomass (150 g/m2 and 120 g/m2), and grass biomass (110 g/m2 and 70 g/m2). Belowground biomass was higher in depressions, although not significantly so (8 g/m2 and 3 g/m2). The plant communities of depressions were dominated by Scribner’s dichanthelium (Dichantheliuum oligosanthes var. scribneriamum) (32% cover), sedges (Carex spp. And Cyperus schweinitzii) (27% cover), little bluestem (Andropogon scoparius) (21% cover), and white sage (Artemisia ludoviciana) (19% cover). Little bluestem (27% cover), western ragweed (Ambroisa psilostachya) (17% cover), and junegrass (Koeleria pyramidata) (13% cover) dominated slope communities. Significant (P < 0.05) differences between depressions and slopes were recorded for soil moisture (3% and 2%), soil organic matter (2% and 1%), depth of humic acid staining (120 cm and 40 cm), and 3 of 7 soil particle sizes, including silt. Most of the 19 elements tested had higher concentrations in depressions, but significant differences were recorded for iron, potassium, manganese, silicon, and zinc. Significantly higher proportions of small mineral soil particles, organic matter, and nutrients suggest that depressions may act as a regional sink for air-borne particulates that, in combination with higher soil moisture, support a substantially different plant community than the surrounding prairie matrix. This, interdunal depressions appear to contribute significantly to the landscape-level diversity of the Sandhills Prairie ecosystem.

On The Nature Of Norms: Biology, Morality, And The Disruption Of Order, Owen D. Jones

Vanderbilt Law School Faculty Publications

This essay discusses the legal implications of bio-behavioral underpinnings to norms, morality, and economic order. It first discusses the recent book "The Great Disruption: Human Nature and the Reconstitution of Social Order," in which Francis Fukuyama explores the importance of evolved human nature to the reconstruction of social order and a thriving economy. It then addresses the extent to which we can usefully view law-relevant norms as products of evolutionary - as well as economic - processes.

Qualitative And Quantitative Chances In Ubiquitin Transcripts During Dictyostelium Mucoroides Development., Vincent Van Rothe

Student Work

The slime mold Dictyostelium mucoroides is an effective model for studying eukaryotic development because it exists as both unicellular and multicellular entities depending on the stage of their life cycle. Development is regulated by a number of proteins. During the transition from single amebas to a multicellular entity, developmentally regulated proteins appear. In the case of the microcysts, produced during sexual reproduction, proteins not only function in the formation of the cell walls, but also aid in the fusion of gametes, selective phagocytosis, cell to cell contact, and make up lysosomal enzymes. We have cloned a developmentally regulated gene whose …

The Early Local And Regional Immune Response To Recall Inoculations Of Mycobacterium Leprae In The Skin Of Rhesus Macaques (Macaca Mulatta)., Thomas Xavier D Lemarchand

LSU Historical Dissertations and Theses

Epidemiological studies have failed to show any important impact of human immunodeficiency virus (HIV) infection and disease on leprosy, in contrast to the well documented increase in incidence and morbidity with other mycobacteria in these patients, notably Mycobacterium tuberculosis. The early events following exposure and repeated exposure to Mycobacterium leprae (ML) have not still been studied. Previous studies of first inoculations of ML in the skin of rhesus monkeys have indicated delayed recruitment of CD4+ cells and delayed interleukin (IL) 2 secretion in skin inoculation sites in simian immunodeficiency (SIV) positive animals. The development of the secondary immune response against …

Dna Alkylation And Its Repair In Small Fish Species., Thomas James Vicek

LSU Historical Dissertations and Theses

Mechanisms of DNA alkylation and repair were investigated in 3 small fish species. Following aqueous exposure to either N-methyl- N'-nitro-N-nitrosoguanidine or ethyl methanesulfonate, the hepatic DNA from the western mosquitofish, Gambusia affinis, was analyzed for alkyl-DNA adducts via high performance liquid chromatography - mass spectrometry/mass spectrometry. Although potential tissue detection limits ranged from 14--101 fmoles of alkyl adducts/mg tissue, no alkyl-DNA adducts were detected in the exposed tissues. To assess the potential repair of alkyl-DNA adducts in 2 other small fish species, alkyltransferase activities within hepatic protein extracts of the Gulf killifish, Fundulus grandis, and Gambusia affinis were determined using …

Biometrical Models For Predicting Future Performance In Plant Breeding., Monica Graciela Balzarini

LSU Historical Dissertations and Theses

The plant breeding process begins with the selection of parents and crosses. Promising progeny from these crosses progress through a series of selection stages that typically culminate in multi-environment trials. I evaluated best linear unbiased predictors (BLUP), other predictors and prediction models at the initial (cross prediction), early replicated testing and late (multi-location) stages of a sugarcane breeding selection cycle. Model and predictor accuracy was assessed in the first two stages by using cross-validation procedures. I compared statistical models of progeny test data in their ability to predict the cross performance of untested sugarcane crosses. Random parental effect predictors and …

Pathogenesis Of Bartonella Henselae In The Domestic Cat: Use Of A Pcr-Based Assay For The Detection And Differentiation Of B. Henselae Genotype I And Genotype Ii In Chronically Infected Cats., Alma Faye Roy

LSU Historical Dissertations and Theses

Bartonella henselae is a zoonotic agent in which the domestic cat serves as the natural reservoir, and humans acquire potentially serious infections associated with this microorganism. The purpose of this research is to contribute to the understanding of the pathogenesis of B. henselae in the domestic cat using a molecular approach. Using sequence differences in a portion of the I 6S rRNA gene between B. henselae genotype I, and B. henselae genotype II, a nested polymerase chain reaction (nPCR) was designed and used to investigate various phases of feline bartonellosis. The nPCR detected 3.2 organisms per milliliter of blood which …

Glucocorticoid Regulation Of The Leptin Receptor Signaling System In The Rat., Abram Madimabe Madiehe

LSU Historical Dissertations and Theses

Obesity, a recognized health problem, is associated with cardiovascular disease, diabetes and hypertension. Removal of adrenal steroids by adrenalectomy (ADX) slows the development of obesity. Leptin decreases food intake through effects initiated by activation of the JAK-STAT pathway. Defects in leptin signaling lead to obesity, which is associated with hyperleptinemia and leptin resistance. In chapter 4, leptin induces phosphoenolpyruvate carboxykinase (PEPCK) mRNA expression and increases glucose production in hepatocytes from lean but not obese Zucker rats. This suggests that hyperleptinemia in obesity causes hyperglycemia. In chapter 5, ADX decreased the levels of PEPCK mRNA, and increased leptin receptor mRNA expression …

Characterization Of The Interactions Within The Ccr4 -Not Complex And The Interactions Between Adr1 And Tfiid Components, Yongli Bai

Doctoral Dissertations

The mechanisms of transcriptional regulation are well conserved from yeast to human cells. Most genes are regulated at the transcriptional level, particularly, at the transcription initiation step. In Saccharomyces cerevisiae at least one transcriptional activator, ADR1, and one transcription complex, CCR4-NOT, participate in the activation of the ADH2 gene. The core 1 x 106 dalton CCR4-NOT complex consists of CCR4, CAF1, the five NOT proteins (NOT1-NOT5), and three other uncharacterized proteins. Deletion of NOT3, NOT4, or NOT5 did not affect the association of CCR4 with CAF1 in the gel filtration analysis. In contrast, NOT2 inactivation caused partial destabilization of the …

The Effects Of Ultraviolet Radiation, Highway Contamination, And Synergism Of The Two On Spotted Salamander Embryos, Sarah Letitia Turtle

Doctoral Dissertations

In this study, I examined the effects of ultraviolet radiation, highway contamination and a synergism of both factors on the spotted salamander, Ambystoma maculatum embryos in field and laboratory experiments. There are numerous reports of amphibian population declines from around the world. There are several possible factors causing the decline, including, habitat loss, environmental pollution, disease, and ultraviolet B radiation (UVB, 290--320 nm). Results of studies conducted to date seem to indicate that the impacts of these factors vary greatly among species and across geography. Amphibians have unique characteristics and life histories that make them more vulnerable to changes in …

Remote Sensing Of Forest Damage In The Czech Republic Using Hyperspectral Methods, Petya K. Entcheva

Doctoral Dissertations

The current study assesses the potential of hyperspectral data for monitoring the initial stages of damage in Norway spruce forests characterized by subtle changes in foliar chlorophyll and chemistry. Both field and airborne high spectral resolution reflectance measurements were obtained for selected study sites in the Krusne hory, Czech Republic.

High spectral resolution airborne canopy data and field foliar samples were acquired simultaneously in August 1998 for a total of 51 study sites within the Krusne hory. The sites were selected to represent a full range of damage conditions in even-aged Norway spruce (Picea abies (L.) Karst) stands located between …

Disturbance Indicators For Time Series Reconstruction And Marine Ecosystem Health Impact Assessment, Benjamin Harrison Sherman

Doctoral Dissertations

A systematic reconstruction of Multiple Marine Ecological Disturbances (MMEDs) involving disease occurrence, morbidity and mortality events has been undertaken so that a taxonomy of globally distributed marine disturbance types can be better quantified and common forcing factors identified. Combined disturbance data include indices of morbidity, mortality and disease events affecting humans, marine invertebrates, flora and wildlife populations. In the search for the best disturbance indicators of ecosystem change, the unifying solution for joining data from disparate fields is to organize data into space/time/topic hierarchies that permit convergence of data due to shared and appropriate scaling. The scale of the data …

Disarticulation And Dissolution Of Crab Remains Across A Depth Gradient In The Bahamas: A Taphonomic Study, Rebecca A. Lincoln

Honors Papers

The fields of Paleontology and Paleoecology would not be complete without taphonomy, the study of the processes affecting organisms between death and fossilization. Taphonomy is important because it allows us to make more complete conjectures about prehistoric organisms and environments, and makes us aware of possible holes and biases in the fossil record due to highly destructive processes or the loss of delicate, non-resistant organisms. Studies on the processes affecting modern organisms have contributed greatly to the understanding of ancient processes; however, most of these studies are nearshore and short-term. What is lacking is information on the effects of these …

Isolation And Characterization Of Newly Emerging Coronaviruses In Acute Respiratory Tract Diseases Of Cattle., Xiaoqing Lin

LSU Historical Dissertations and Theses

A total of 411 G clone cell-dependent virus strains recently were isolated from nasal, trachea and lung samples in etiological investigations of acute respiratory tract diseases of vaccinated cattle, including shipping fever pneumonia. The virus infectivity titers reached up to 1.2 x 10 7 plaque forming units per gram of lung tissues of fatal cases. These viral agents were isolated in the 1st G clone cell passage without trypsin enhancement, and induced cell fusion. They have a restricted hemagglutination pattern, agglutinating only rat and mouse erythrocytes. Majority of them has receptor-destroying enzyme activities. They are round and enveloped with a …

Evaluation Of Heterologous Promoter Function In The Eastern Oyster (Crassostrea Virginica)., Ta Philip Chih Cheng

LSU Historical Dissertations and Theses

The goal of this work was to evaluate the feasibility of using antimicrobial peptide gene transfer to enhance oyster immunity. The specific objectives were to: (1) compare the efficiency of collagenase, pronase, and trypsin to dissociate atrium, ventricle and mantle into individual cells for the initiation of primary cell culture; (2) develop cryopreservation conditions to preserve the dissociated cells; (3) establish a serum-free transfection system; (4) evaluate inducible promoter function using the established serum-free transfection system; (5) evaluate the effects of the transfer of antimicrobial peptide genes on oyster immunity. Pronase was found to be the most effective enzyme for …

A Case Study In Amazonian Biogeography: Vocal And Dna -Sequence Variation In Hemitriccus Flycatchers., Mario Cohn-Haft

LSU Historical Dissertations and Theses

Ongoing debate about the evolutionary history of the Amazonian avifauna suffers from a shortage of data. Especially needed are thorough geographic sampling, sensitive markers of genetic diversity, and historical data in the form of explicit phylogenies. I examined patterns of geographic variation in three widespread species complexes of nearly identical Amazonian flycatchers in the genus Hemitriccus, based on spectrographic analysis of vocalizations and phylogenetic analysis of DNA sequences (1026 base pairs of cytochrome b from 44 individuals) from throughout Amazonia. Although members of the three complexes are extremely difficult to distinguish morphologically and have long been confused by taxonomists, they …

Oxidation -Reduction Chemistry Of Methane And Nitrous Oxide In Soils And An Approach To Minimize Their Emissions From Irrigated Rice Fields., Kewei Yu

LSU Historical Dissertations and Theses

Rice fields are an important source of the greenhouse gases methane (CH 4) and nitrous oxide (N2O). In this dissertation study, experiments were conducted at three levels---in soil suspensions, in soil cores, and under actual field conditions, to investigate the impact of soil redox potential on CH4 and N2O emissions to the atmosphere. Methane and N2O emissions occurred at distinctively different redox conditions in the homogenous soil suspensions. No significant amounts of CH4 was produced when the soil redox potentials were above -150 mV. In the denitrification process, both N2O production and reduction occurred in the soil redox potential range …

Ecology Of Seagrass Fishes And Macroinvertebrates On Guatemala's Atlantic Coast., Alejandro Arrivillaga

LSU Historical Dissertations and Theses

The ecology of fishes and macroinvertebrates inhabiting shallow seagrass beds was studied at Bahia La Graciosa, located in Amatique Bay in the Caribbean coast of Guatemala. The study area included extensive turtle grass, Thalassia testudinum, meadows over muddy substrate, whereas a more exposed shoreline also supported turtle grass meadows over sandy substrates outside the bay. A total of 166 samples were collected across two seasons and habitat types in three sampling trips to the area with a cylindrical drop sampler. Diversity and abundance of fishes and macroinvertebrates inhabiting seagrass and adjacent bare-sand sites were described to assess the relative importance …

Creation And Characterization Of 25 Kda Outer Membrane Protein (Omp25) Deletion Mutants In Brucella Species., Matthew David Edmonds

LSU Historical Dissertations and Theses

The genus Brucella is composed of Gram-negative, facultative intracellular pathogens that impact man and animals. Brucella species express a 25 kDa major outer membrane protein termed Omp25. To determine the role of Omp25 in virulence, mutants were created in Brucella abortus (BA25), Brucella melitensis (BM25), and Brucella ovis (BO25) that contain disruptions in the omp25 gene (Deltaomp25 mutants). In the murine brucellosis model, each Deltaomp25 mutant was attenuated when compared to the virulent parental strain. To assess the ability of the B. abortus and B. melitensis mutants to colonize and induce abortions in the ruminant host, cattle and goats in …

Insecticide Resistance And Resistance Mechanisms In The Southern House Mosquito, Culex Quinquefasciatus., Jeffrey Dwayne Stancil

LSU Historical Dissertations and Theses

Significant resistance to malathion and resmethrin was found in insecticide-treated field populations of adult Culex quinquefasciatus , Say, compared with a laboratory and non-treated field strain. Resistance to both insecticides varied during the active control season and was associated with the frequency of insecticide application. Geographic variations in resistance levels were noted, and significant differences occurred between separate populations within the same mosquito control districts. Four model substrates were assessed for their suitability in detecting elevated esterase activity associated with malathion resistance. Esterase activities towards all substrates were significantly higher in field stains than a laboratory strain. Esterase activities toward …

Evaluation Of Insecticide Resistance In Louisiana Adult Mosquitoes And The Efficacies Of Selected Larvicides., Stacy Lee Bearden

LSU Historical Dissertations and Theses

Pesticide resistance in Louisiana mosquitoes has never been examined on a state-wide basis. In 1996, first component of this monitoring program examined selected pesticide efficacies and documented current pesticide resistance. Ground ULV-applied FyfanonRTM (96.8% malathion and Pyrocide RTM (96.8% + 1% natural pyrethrum) were applied to caged Culex quinquefasciatus adults (Denham Springs [Livingston Parish] and Lake Charles [Calcasieu Parish]) and Aedes sollicitans (Vermilion Parish). FyfanonRTM caused significantly different (p < 0.05) mortalities among each species and strain within 24hrs (95% Aedes, 48% Denham Springs, and 14% Lake Charles). Pyrocide RTM also produced significantly different mortalities (99%, 70%, and 38%, respectively). Malathion and permethrin were topically applied to 3--5 day old adult mosquitoes from 14 parishes. St. Martin parish Cx. quinquefasciatus was most susceptible to malathion (2.58 mug/mul), and the Vermilion strain was most resistant (417.05 mug/mul). Resistance is based on a ≥5-fold resistance ratio. Calcasieu parish strain was least resistant to permethrin (1.93 mug/mul), and the St. Tammany parish strain was most resistant (40.86 mug/mul). Detecting pesticide resistance by bottle bioassay technique was compared to topical bioassay. Both techniques were effective in detecting resistance for selected Aedes, Anopheles, and Culex species in Louisiana. Ground ULV 97% malathion was applied to caged Cx. quinquefasciatus adults from a mosquito abatement district, agrichemical farmland, and a susceptible colony. No significance (p > 0.05) existed in mosquito mortality between the agrichemical area and the abatement district. Bacillus thuringiensis var. israeliensis (VectoBacRTM WDG and VectoBacRTM 12AS) and Bacillus sphaericus (VectoLexRTM WDG and VectoLexRTM CG) were …

The Effects Of Equine Somatotropin (Est) On Reproductive Function In The Domestic Mare., Richard Anthony Cochran

LSU Historical Dissertations and Theses

The effects of somatotropin on ovarian reproductive function has become a keen research area in mammalian species over the past decade. However, to date, very little information is available as to the effects of somatotropin administration on reproduction in the domestic mare. Therefore, the purpose of these experiments was (1) to determine the potential effects (if any) of administration of exogenous equine somatotropin on ovarian follicular development and plasma and follicular fluid hormone concentrations in cyclic and noncyclic mares, (2) to determine the mechanism(s) of action of somatotropin treatment on these parameters in the mare, (3) to develop an efficient …

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 …

Different Proctolin Neurons Elicit Distinct Motor Patterns From A Multifunctional Neuronal Network, Dawn M. Blitz, Andrew E. Christie, Melissa J. Coleman, Brian J. Norris, Eve Marder, Michael P. Nusbaum

WM Keck Science Faculty Papers

Distinct motor patterns are selected from a multifunctional neuronal network by activation of different modulatory projection neurons. Subsets of these projection neurons can contain the same neuromodulator(s), yet little is known about the relative influence of such neurons on network activity. We have addressed this issue in the stomatogastric nervous system of the crab Cancer borealis. Within this system, there is a neuronal network in the stomatogastric ganglion (STG) that produces many versions of the pyloric and gastric mill rhythms. These different rhythms result from activation of different projection neurons that innervate the STG from neighboring ganglia and modulate STG …

Abstracts Of Papers, 77th Annual Meeting Of The Virginia Academy Of Science, May 26-28, 1999, Old Dominion University, Norfolk, Virginia

Virginia Journal of Science

This document is a list of abstracts presented at the 77th annual meeting of the Virginia Academy of Science, between May 26 and May 28th, 1999, at Old Dominion University.

Dissolved Organic Carbon Cycling In A Subtropical Seagrass-Dominated Lagoon, Susan Ziegler, Ronald Benner

Faculty Publications

The cycling of dissolved organic matter (DOM) and its significance to ecosystem metabolism was studled over a 16 mo period in a Thalassia testudjnum dominated meadow. The benthos was usually net autotrophic (annual gross primary production to respiration ratio [P:R] = 1.3) while water column respiration (R) exceeded gross primary production (annual P:R = 0.3). Net fluxes of dissolved organic carbon (DOC) from the benthos primarily occurred in the light (0 to 18 mmol C m^-2 d^-1) and from seagrass-dominated areas, suggesting that release of DOC was mainly due to seagrass exudation. Net benthic DOC fluxes measured …

Mechanisms Of Immunotherapeutic Intervention By Anti-Cd40l (Cd154) Antibody In An Animal Model Of Multiple Sclerosis, Laurence M. Howard, Amy J. Miga, Carol L. Vanderlugt, Mauro C. Dal Canto, John D. Laman, Randolph J. Noelle, Stephen D. Miller

Dartmouth Scholarship

Relapsing experimental autoimmune encephalomyelitis (R-EAE) in the SJL mouse is a Th1-mediated autoimmune demyelinating disease model for human multiple sclerosis and is characterized by infiltration of the central nervous system (CNS) by Th1 cells and macrophages. Disease relapses are mediated by T cells specific for endogenous myelin epitopes released during acute disease, reflecting a critical role for epitope spreading in the perpetuation of chronic central CNS pathology. We asked whether blockade of the CD40–CD154 (CD40L) costimulatory pathway could suppress relapses in mice with established R-EAE. Anti-CD154 antibody treatment at either the peak of acute disease or during remission effectively blocked …

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 …