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The Biology And Ecology Of The Yellowmargined Leaf Beetle, Microtheca Ochroloma Stal, (Coleoptera: Chrysomelidae) On Crucifers., Abdullahi Olod Ameen
The Biology And Ecology Of The Yellowmargined Leaf Beetle, Microtheca Ochroloma Stal, (Coleoptera: Chrysomelidae) On Crucifers., Abdullahi Olod Ameen
LSU Historical Dissertations and Theses
The biology and ecology of the yellowmargined leaf beetle, Microtheca ochroloma Stal, were studied on cabbage, Brassica oleracea var capitata L., collard, B. oleracea var acephala L., mustard, B. juncea Cosson, turnip, B. rapa L., and radish, Raphanus sativus L. The life cycle of the beetle consists of an egg stage, four larval instars, prepupal, pupal and adult stages. There were no significant differences in the effect of host plant on duration of development of immature beetles (p = 0.3353). The mean duration of development from oviposition to adult emergence ranged from 26.6 d on turnip to 27.5 d on …
Community Structure And Habitat Preferences Of Intertidal Fishes Of The Eastern Canary Islands: Fuerteventura, Gran Canaria, And Lanzarote, With A Behavioral Description Of Mauligobius Maderensis (Osteichthyes: Gobiidae)., Richard Patrick Cody
LSU Historical Dissertations and Theses
Community structure and relative habitat preferences of intertidal fishes from the eastern Canary Islands of Fuerteventura, Gran Canaria, and Lanzarote were examined in a study of 354 tidepools at 33 localities. Habitat use and behavior of the most abundant fish Mauligobius maderensis were examined on Gran Canaria and Lanzarote. Of the 27 species encountered, 11 were common to each of the islands. The most abundant species were: M. maderensis, Parablennius parvicornis, Gobius paganellus, Coryphoblennius galerita, and Chelon labrosus. In a Two-way indicator species analysis Fuerteventura and Lanzarote localities clustered together. The same analysis differentiated between species that inhabited the upper …
Importance Of A Siderophore In The Pathogenesis And Virulence Of Photobacterium Damsela Subsp. Piscicida In Hybrid Striped Bass (Morone Saxatili X Morone Chrysops)., John Phillip Hawke
Importance Of A Siderophore In The Pathogenesis And Virulence Of Photobacterium Damsela Subsp. Piscicida In Hybrid Striped Bass (Morone Saxatili X Morone Chrysops)., John Phillip Hawke
LSU Historical Dissertations and Theses
Photobacterium damsela subsp. piscicida, formerly Pasteurella piscicida, is an important new pathogen of hybrid striped bass cultured in brackish water on Louisiana mariculture farms. Louisiana isolates compared with strains of P. damsela subsp. piscicida from Greece, Japan, Israel and Chesapeake Bay, USA and were found to be identical in biochemical phenotype and enzymic activity. Small plasmids of 8 and 5 kb were unique to Louisiana strains. Sequential daily bacteriology and histopathology on hybrid striped bass experimentally infected by immersion revealed that following high doses (13,000 CFU/ml) the gills and spleen are colonized first as early as 24 hours PI, followed …
Cloning, Sequencing And Regulation Of The Rhodobacter Capsulatusheme Gene., Georgia Ineichen
Cloning, Sequencing And Regulation Of The Rhodobacter Capsulatusheme Gene., Georgia Ineichen
LSU Historical Dissertations and Theses
In Rhodobacter capsulatus, a purple nonsulfur bacterium, the tetrapyrrole pathway yields four end products: siroheme, vitamin B12, heme and bacteriochlorophyll. Growth of R. capsulatus under low oxygen tension increases carbon flow through the tetrapyrrole pathway up to 100 fold. The mechanism(s) for this regulation is currently unknown. One regulatory mechanism could be transcriptional control of one or more of the genes in the common portion of the tetrapyrrole pathway. The fifth gene in the pathway, hemE, has been cloned by complementation of an Escherichia coli hemE::miniTn10 mutant. Sequence data of hemE revealed the presence of an upstream palindrome that is …
The Role Of Seed Banks, Disturbance, And Sea Level Rise In Determining The Plant Community Structure Of Oligohaline Coastal Marshes., Andrew Hamilton Baldwin
The Role Of Seed Banks, Disturbance, And Sea Level Rise In Determining The Plant Community Structure Of Oligohaline Coastal Marshes., Andrew Hamilton Baldwin
LSU Historical Dissertations and Theses
Coastal wetlands worldwide are threatened by sea level rise, which is expected to affect the growth and survival of wetland vegetation by increasing water level and salinity. While the effects of salinity and inundation on adult vegetation of oligohaline marshes have been widely studied, the species composition of the seed bank and its response to elevated salinity and water level have not been examined. Additionally, the role of disturbances of different intensities in structuring marsh plant communities and possible interactions between disturbance and rising sea level have received little attention. Disturbances in coastal marshes include nonlethal disturbances such as fire …
Impacts Of Fire And Vertebrate Herbivores On Plant Community Characteristics And Soil Processes In A Coastal Marsh Of Eastern Louisiana, United States Of America., Mark Alan Ford
LSU Historical Dissertations and Theses
Both vertebrate herbivores and fire have long been known to have dramatic and important effects on wetlands. In the first part of this study, conducted in the Pearl River Basin coastal marshes of Louisiana, the interaction between the effects of mammalian herbivores, especially nutria and wild boar, and fire was examined in three marsh community types: those dominated by Sagittaria lancifolia, Panicum virgatum, or Spartina patens/Scirpus americanus. Overall, above-ground biomass was reduced by burning but increased by fencing. Richness only increased in plots that were both burned and fenced. In the three communities, only Scirpus americanus cover was enhanced by …
Regulation Of Interrenal Steroidogenesis In Elasmobranchs., Brian Scott Nunez
Regulation Of Interrenal Steroidogenesis In Elasmobranchs., Brian Scott Nunez
LSU Historical Dissertations and Theses
This study investigated the steroidogenic enzymes of the elasmobranch interrenal. First, biochemical characteristics of cytochrome P450c21 hydroxylase (P450c21) and 3$\beta$-hydroxysteroid dehydrogenase (3$\beta$-HSD) were determined with incubations of the microsomal fraction of Carcharhinus limbatus (blacktip shark) interrenal tissue. Second, molecular reagents were obtained by isolating and sequencing partial cDNA clones encoding the elasmobranch steroidogenic enzymes cytochrome P450 side chain cleavage (P450scc) and 3$\beta$-HSD from blacktip shark and Daysatis americana (southern stingray) interrenal. Finally, the regulation of Daysatis sabina (Atlantic stingray) interrenal steroidogenesis by peptide hormones such as corticotropin (ACTH) and angiotensin II was investigated by in vitro incubations of interrenal tissue. …
Postexercise Hypotension (Peh) In The Dog: Possible Role Of Immune System Cytokines., Gerald Dwayne Thompson
Postexercise Hypotension (Peh) In The Dog: Possible Role Of Immune System Cytokines., Gerald Dwayne Thompson
LSU Historical Dissertations and Theses
This study investigated postexercise hypotension (PEH) in five normotensive dogs testing these hypotheses: (1) PEH is present in the dog model; (2) high intensity exercise of 85% HR$\rm\sb{max}$ as compared to moderate intensity exercise of 60% HR$\rm\sb{max}$ induces a greater PEH; and (3) IL-1 and its activation of PGE$\sb2$ are associated with PEH. In experiment I, it was found that 85% HR$\rm\sb{max}$ exercise decreased systolic blood pressure (SBP) and mean arterial blood pressure (MABP) at 30 and 60 minutes postexercise (p $<$ 0.05). Both IL-1 and PGE$\sb2$ increased immediately following intense exercise, although temporal patterns were dissimilar. During non-exercise infusion of ibuprofen or dexamethasone (experiment II), blood pressure was not affected, but ibuprofen led to an overall inhibition of PGE$\sb2$. However, dexamethasone infusion led to a significant increase in PGE$\sb2$ at 180 and 210 minutes postinfusion. In experiment IIIA, after intense exercise following ibuprofen or saline infusion, PGE$\sb2$ increased at 120 to 180 minutes postexercise. Similar results were noted after exercise during dexamethasone treatment (experiment IIIB). In experiment IIIA & B, neither ibuprofen nor dexamethasone significantly affected PEH, although non-significant reductions in PEH was observed in dexamethasone treated animals. However, PGE$\sb2$ significantly increased after exercise at time points when PEH was not observed. These data indicate that (1) the intensity of exercise may have an effect on PEH, (2) there is partial support for the involvement of IL-1 and PGE$\sb2$ in PEH due to their immediate increase after exercise although a direct relationship was not observed, and (3) IL-1 still remains a possible mechanism responsible for PEH because of trends for attenuated PEH and PGE$\sb2$ responses following dexamethasone treatment.
Ion Transport In The Freshwater Bivalve, Corbicula Fluminea (Muller)., Huiyuan Zheng
Ion Transport In The Freshwater Bivalve, Corbicula Fluminea (Muller)., Huiyuan Zheng
LSU Historical Dissertations and Theses
Corbicula fluminea (Muller) maintains hydromineral balance in dilute media by active transepithelial transport of Na and Cl. Cl uptake depended on external (Cl) and displayed saturable kinetics. The transport capacity in pondwater(PW)-acclimated animals was 7.00 $\pm$ 0.51 $\mu$eq(g dry tissue $\cdot$ h)$\sp{-1}$ and the transport affinity 0.21 $\pm$ 0.08 mM. Prolonged salt depletion increased Cl transport capacity without changing the affinity. In PW-acclimated C. fluminea, Na and Cl transport were independent, and were stimulated by serotonin. In salt depleted (SD)animals, Na transport was partially Cl-dependent but Cl transport was Na-independent. Acetazolamide increased Na and Cl efflux. Both serotonin and acetazolamide …
Role Of Hurricane Disturbance In The Dynamics Of The Southern Mixed Hardwood Forest: A Case Study In Northern Florida., William Bennett Batista
Role Of Hurricane Disturbance In The Dynamics Of The Southern Mixed Hardwood Forest: A Case Study In Northern Florida., William Bennett Batista
LSU Historical Dissertations and Theses
The objective of this dissertation was to characterize the role of hurricanes in the dynamics of old-growth Southern Mixed Hardwood Forests from the coastal plain of the northern Gulf of Mexico. First, we used data from five stands to describe the structure, composition, and disturbance regime of these forests. All five stands have Magnolia grandiflora and Fagus grandifolia among the dominant species, and have been affected by frequent but relatively mild hurricanes (4-6 per century, windspeed $<$200 km/h). Second, we examined the changes in tree recruitment, growth, and mortality occurred in Woodyard Hammock, northern Florida, after this forest was affected by Hurricane Kate in 1985. The analysis was based on data from biennial censuses of a 4.5 ha plot conducted between 1978 and 1992. Hurricane Kate produced extensive canopy disruption but limited tree mortality. This disturbance prompted a phase of increased recruitment, growth, and survival of understory trees, and decreased growth and survival of overstory trees. Release of small understory individuals appeared to be critical for the persistence of three short-lived dominant species, Pinus glabra, Ostrya virginiana and Carpinus caroliniana. However, persistence of the longer-lived dominants Magnolia grandiflora, Fagus grandifolia, Liguidambar styraciflua, Nyssa sylvatica, and Ilex opaca, appeared to depend primarily on resistance to hurricane damage. Third, we used matrix population models to test specific hypotheses about mechanisms of persistence of F. grandifolia in Woodyard Hammock. These models showed that, both before and after Hurricane Kate, this population was close to equilibrium. This result supported the hypothesis that persistence of F. grandifolia has resulted from hurricane resistance. Sensitivity analyses of the models suggested that the key for hurricane resistance has been the high survival of medium-size trees. Life-history strategies involving resistance and survival to hurricane disturbance, rather than release and rapid growth, appear to have been prevalent in these forests. However, the hurricane regime would have resulted in coexistence of species with the two types of strategy. Hurricanes would have been frequent enough to secure the persistence of species dependent on release, and mild enough not to compromise that of species dependent on resistance.
Molecular Systematics Of Red Algae., Jeffrey Craig Bailey
Molecular Systematics Of Red Algae., Jeffrey Craig Bailey
LSU Historical Dissertations and Theses
Phylogenetic analyses of nucleotide sequences for the nuclear-encoded small subunit ribosomal RNA (SSU) gene were used to test current hypotheses of relationships within the Corallinales and among the florideophycidaean orders of red algae. Analyses of SSU gene sequences indicate that the order Corallinales includes four major lineages. The Sporolithaceae is resolved as the earliest-diverging lineage within the order and forms the sister group to a monophyletic Corallinaceae. The molecular data also support the monophyly of the subfamilies Melobesioideae and Corallinoideae. The latter subfamily is inferred as sister to a fourth lineage including non-geniculate and geniculate species classified in the subfamilies …
Low Carbon Dioxide-Inducible Genes And Proteins In Chlamydomonas Reinhardtii., Zhi-Yuan Chen
Low Carbon Dioxide-Inducible Genes And Proteins In Chlamydomonas Reinhardtii., Zhi-Yuan Chen
LSU Historical Dissertations and Theses
At low CO$\sb2$ conditions, C. reinhardtii, like many other green algae, induces a CO$\sb2$ Concentrating Mechanism (CCM) to raise the internal Ci concentration. During the induction, at least five new polypeptides and six different genes are upregulated and some of the corresponding mRNAs or proteins are absent in high CO$\sb2$ requiring mutants. However the identities and functions of these genes are unknown. In this dissertation, I partially characterized four low CO$\sb2$ inducible genes and one low CO$\sb2$ inducible protein LIP-36. The complete cDNA sequences of clones 11I3 and 2I5 are 1311 bp and 985 bp, respectively. Neither of these two …
Physical And Functional Characterization Of Long Terminal Repeat Of Equine Infectious Anemia Virus., Soo Ho Kim
Physical And Functional Characterization Of Long Terminal Repeat Of Equine Infectious Anemia Virus., Soo Ho Kim
LSU Historical Dissertations and Theses
The U3 region of long terminal repeat (LTR) of equine infectious anemia virus (EIAV) contains transcriptional regulatory elements. To identify the elements in prototype (P), fetal donkey dermal cell-adapted (A), and two variant (V) EIAV LTRs, DNase I footprinting, gel shift, and transient gene expression assays were performed. The assays used U937 monocytic cells which can be induced into macrophages by 12-O-tetradecanoylphorbol-13-acetate (TPA). For study of AP1 sites, c-Jun/AP1 was also used. Footprinting with nuclear extracts from TPA-induced and uninduced U937 cells localized methylated DNA-binding protein (MDBP), PEA2, AP1, PU.1, and CCAAT enhancer-binding protein (C/EBP) sites as common elements in …
The Cytoplasmic N,N'-Diacetylchitobiase Gene From Vibrio Parahaemolyticus: Sequence Analysis, Protein Secretion, And Secretion System Development., Michael Hongli Wu
The Cytoplasmic N,N'-Diacetylchitobiase Gene From Vibrio Parahaemolyticus: Sequence Analysis, Protein Secretion, And Secretion System Development., Michael Hongli Wu
LSU Historical Dissertations and Theses
The nucleotide sequence of the gene encoding the cytoplasmic $N,N\sp\prime$-diacetylchitobiase from Vibrio parahaemolyticus has been determined. The deduced peptide sequence surprisingly has minimum evolutionary relationship to two other reported $N,N\sp\prime$-diacetylchitobiases from vibrios, except for highly conserved regions which are also homologous with lysosomal beta-hexosaminidases from eukaryotes including humans. In contrast, the other two sequenced chitobiases from vibrios are much more closely related to each other. This 85 kDa cytoplasmic protein, as revealed from the sequence, appears to be a unique protein, lacking a signal sequence and genetically distant from other known enzymes of similar function. This is consistent with its …
Relationships Between Brain Biogenic Amines And Reproductive And Defense Behavior In Honey Bees (Apis Mellifera L.)., Jeffrey Wayne Harris
Relationships Between Brain Biogenic Amines And Reproductive And Defense Behavior In Honey Bees (Apis Mellifera L.)., Jeffrey Wayne Harris
LSU Historical Dissertations and Theses
This dissertation represents an attempt to relate behavioral states of worker honey bees to brain levels of biogenic amines. The first chapter describes the results of experiments which indicated that brain levels of octopamine, dopamine and serotonin were affected by factors including the degree of handling stress, worker age, season of sampling and the source colony from which the workers were sampled. These results helped shape the methods employed in the subsequent chapters. The second and third chapters relate changes in brain dopamine levels to worker honey bee ovarian development. In particular, chapter II showed that an increase in brain …
Relationship Of Catecholamines And Glucocorticoids To Lymphoproliferation Of Equine Peripheral Blood Mononuclear Cells., Lavanya Potla
Relationship Of Catecholamines And Glucocorticoids To Lymphoproliferation Of Equine Peripheral Blood Mononuclear Cells., Lavanya Potla
LSU Historical Dissertations and Theses
Stress has been related to increased plasma epinephrine (E), norepinephrine (NE), and glucocorticoids. These compounds produce immunomodulatory effects by interacting with hormone receptors on or in various immune cells. This project assessed the effects of stress on equine influenza virus (EIV)-specific and mitogen-induced lymphoproliferation of peripheral blood mononuclear cells (PBMCs) in relation to stress-induced changes in E, NE, and cortisol. In vitro effects of amines on proliferative responses and glucocorticoid receptor (GR) assays were done as a secondary measure of hormone and neurotransmitter interactions with the immune system. Time-dependent, saturable-specific hormone binding to GRs was abolished by heat treatment and …
Movements, Habitat Use, And Survival Of Female Northern Pintails In Southwestern Louisiana., Robert Ripley Cox Jr
Movements, Habitat Use, And Survival Of Female Northern Pintails In Southwestern Louisiana., Robert Ripley Cox Jr
LSU Historical Dissertations and Theses
I developed portable platforms for setting rocket nets in open-water habitats, and used them to capture 1116 waterfowl of 7 species during winters 1991-92 and 1992-93 in southwestern Louisiana. Distance and duration of evening flights of female northern pintails (Anas acuta; hereafter pintails) from Lacassine National Wildlife Refuge increased with date within wintering period, and generally were greater than previously reported estimates for wintering waterfowl. I found that diurnal use of refuges by females increased during hunting seasons, contradicting Tamisier's hypothesis that use of refuges by pintails in southwestern Louisiana is not influenced by hunting. Female pintails extensively used privately …
Biochemical And Biophysical Studies Of Wild-Type And Active-Site Mutants Of Human Adenosine Deaminase., Qing Zeng
LSU Historical Dissertations and Theses
The focus of this work is structural and functional studies of wild-type and active-site mutants of human adenosine deaminase. Two active-site amino acids, Glu217 and His238, were previously substituted with alanine by site-directed mutagenesis. The Glu217Ala and His238Ala mutants showed little or no changes in Zn content and $\rm K\sb{m}$ value, yet dramatic loss of enzyme activity. Circular dichroism studies of the solution conformation of wild-type and mutant human adenosine deaminases indicate that 30 to 50% of $\alpha$-helical structure is lost in Glu217Ala and His238Ala, respectively, whereas $\beta$-sheet structure is fully retained. Inhibitor binding is measured by a fluorescent assay. …
Spatial Distribution And Sequential Sampling Of The Rice Water Weevil, Lissorhoptrus Oryzophilus Kuschel, In Louisiana., Mark Alan Muegge
Spatial Distribution And Sequential Sampling Of The Rice Water Weevil, Lissorhoptrus Oryzophilus Kuschel, In Louisiana., Mark Alan Muegge
LSU Historical Dissertations and Theses
Studies were conducted in Louisiana to determine the spatial and temporal distribution of rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel, adults, eggs, larvae and pupae in drill-seeded rice. In addition, three sequential sampling plans, Kuno's fixed precision sequential sampling plan, the sequential probability ratio test (SPRT), and 2-SPRT, were developed and evaluated to establish an accurate and economically efficient sampling plan for RWW larvae in drill-seeded rice in Louisiana. Values obtained for the aggregation indices, b, from Taylor's power law, $\beta$, from Iwao's patchiness regression and, k, from the negative binomial distribution indicated that RWW larvae were nearly randomly distributed …
Characterization Of Ionizing Radiation Sensitive (Irs) Mutants Of Deinococcus Radiodurans R1., Kumaraswamy S. Udupa
Characterization Of Ionizing Radiation Sensitive (Irs) Mutants Of Deinococcus Radiodurans R1., Kumaraswamy S. Udupa
LSU Historical Dissertations and Theses
Deinococcus radiodurans is extremely resistant to ionizing radiation and can withstand 5 kGy $\gamma$ radiation without loss of viability or evidence of mutation. Available evidence argues that an efficient DNA repair mechanism is responsible for the resistance these organisms possess to ionizing radiation. The enzymes which coordinate DNA repair in D. radiodurans are poorly characterized. Two new loci have been detected in D. radiodurans, namely, irrB and irrI which provide resistance. Mutational inactivation of either locus resulted in a partial loss of resistance to ionizing radiation. The extent of sensitivity was locus specific and differentially affected by inactivation of the …
Interaction Between Ap-1 Proteins And Glucocorticoid Receptors In Regulation Of Lymphokine Activated Killer (Lak) Cell Activity In The Equine Species., Jing Bu
LSU Historical Dissertations and Theses
This project was performed in order to determine whether exercise-induced increases in plasma cortisol concentrations may be responsible for enhanced lymphokine activated killer (LAK) cell activity. Secondly, this project included preliminary experments which were designed to test the hypothesis that stimulatory effects of cortisol on LAK cell activity may be due to cross-talk between signalling systems important to glucocorticoid effects and stimuli which act through nuclear activator protein-1 (AP-1). Blood samples were collected from resting horses in order to determine whether the animals had normal plasma glucocorticoid concentrations. All horses included in these experiments had $10\sp{-7}$ to $10\sp{-8}$M cortisol concentrations …
The Relationship Of Hemolymph Sugar, Juvenile Hormone And Biogenic Amines To The Three Behavioral States Of Mature Honey Bees., Janko Bozic
LSU Historical Dissertations and Theses
Differences in sugar titers, JH synthesis rate and biogenic amine metabolism correlated with three distinct activity groups or mature bees: resting bees, followers and dancers. Dancers had lower trehalose titers than followers or resting bees. In absconding bees trehalose titers were even lower, due to greatly elevated locomotor activity. The collecting and transferring of food by dancers and followers resulted in a higher glucose titer than in resting bees. Followers had a higher-JH synthesis rate than dancers, suggesting that JH could be an internal motivational stimulus to recruit followers to forage. Dancers and followers collect and transfer food and therefore …
Experimental Lymphatic Filariasis In Gerbils (Meriones Unguiculatus): Molecular Cloning And Expression Of Gerbil Cytokines And Measurement Of Cytokine Gene Expression During A Primary Infection Of Brugia Pahangi., Zhiming Mai
LSU Historical Dissertations and Theses
Cytokines play an important role in regulation of T cell responses. Two T helper cell subsets have been identified in some species and are defined by their cytokine secretion profiles. Th1 cells produce IL-2 and IFN-$\gamma,$ whereas Th2 cells express IL-4, IL-5, and IL-10. Precursor T cells that express a mixture of these cytokines are considered Th0 cells. It is hypothesized that primary infections of Brugia pahangi in gerbils induce an initial Th0 or Th1 like response which with time becomes a Th2 like response. To test this dynamic parasitism induced shift in cytokine profile, it is necessary to measure …
Plant Species Diversity And Community Structure In A Louisiana Coastal Marsh., Laura Gough
Plant Species Diversity And Community Structure In A Louisiana Coastal Marsh., Laura Gough
LSU Historical Dissertations and Theses
The factors that control plant species diversity have been examined by many researchers, but with little consensus as to the causes of diversity patterns. Plant diversity has been correlated with disturbance, competition, soil resources, and other variables. In the research presented here, I investigated the relationship between plant species richness and biomass, competition, nutrient enrichment, flooding, salinity, and herbivory in field studies in Louisiana coastal marshes. Biomass alone was a poor predictor of richness in two Louisiana marshes. When environmental variables (flooding, salinity, and soil fertility) were included with biomass in a multiple regression model, 82% of the variance in …
Toxicity Of Polycyclic Aromatic Hydrocarbons To Benthic Invertebrates., Guilherme R. Lotufo
Toxicity Of Polycyclic Aromatic Hydrocarbons To Benthic Invertebrates., Guilherme R. Lotufo
LSU Historical Dissertations and Theses
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants in aquatic environments. Because of their hydrophobicity, PAHs accumulate in bed sediments and pose a risk to the benthos. Information on the toxicity of sediment-associated PAHs is, however, limited and more information is needed to improve sediment quality-criteria and ecological-risk assessments. My research focused on improving our current knowledge of the acute and, especially, the sublethal effects of sediment-associated PAHs to aquatic invertebrates. Representatives of two phylogenetically distinct benthic invertebrate groups, freshwater tubificid oligochaetes and estuarine meiobenthic harpacticoid copepods, were used. Organisms were exposed to a range of concentrations of sediment-amended contaminants in …
Floral Development And Systematics Of The Caesalpinieae (Leguminosae: Caesalpinioideae)., Katherine Ellen Kantz
Floral Development And Systematics Of The Caesalpinieae (Leguminosae: Caesalpinioideae)., Katherine Ellen Kantz
LSU Historical Dissertations and Theses
The floral development of representatives from some of the informal taxonomic groups of the Caesalpinieae was examined. The floral developmental data was then used in a phylogenetic analysis in combination with more traditional morphological characters, including floral, vegetative and fruit characters. The analysis of 53 taxa and 84 characters produced 1215 equally parsimonious trees of length 386 (CI =.317, RI =.585, RCI =.186). Based on this analysis Caesalpinia sensu lato is not monophyletic, since at least two of the other genera in the Caesalpinia group are nested within Caesalpinia sensu lato. Of the infrageneric groups within Caesalpinia sensu lato, the …
The Association Between Chronic Aerobic Activity And Heart Rate Variability In Patients With Coronary Artery Disease., Robert Howard Wood
The Association Between Chronic Aerobic Activity And Heart Rate Variability In Patients With Coronary Artery Disease., Robert Howard Wood
LSU Historical Dissertations and Theses
Poor heart rate variability (HRV) among patients with coronary artery disease (CAD) is predictive of future incidence of sudden arrhythmic and all-cause death. Furthermore, mental stress appears to further depress HRV in these patients. Chronic aerobic activity level appears to be positively related to HRV among the general population; however, the extent to which this relationship exists among patients with CAD is not clear. Therefore, this study investigated the association between level of chronic aerobic activity and HRV among CAD patients during conditions of paced respiratory control and during the Stroop Color-Word Conflict Test (CWCT). CAD patients were assigned to …
Cytogenetic And Molecular Analysis Of The Channel Catfish (Ictalurus Punctatus) Genome., Quiyang Zhang
Cytogenetic And Molecular Analysis Of The Channel Catfish (Ictalurus Punctatus) Genome., Quiyang Zhang
LSU Historical Dissertations and Theses
This research presents studies on cytogenetics and molecular genetics of channel catfish (Ictalurus punctatus), the most important fish species cultured in the United States. The goals of this project were to analyze the genome of the channel catfish and to develop a direct method of mapping single-locus genes. A series of techniques were developed to facilitate these studies, including culture of fibroblast cells, preparation of chromosomes from catfish of different ages, staining for nucleolus organizer regions (NOR) and heterochromatin (C-banding), restriction enzyme banding, replication R-banding, simultaneous detection of sister-chromatid exchange (SCE) and C-banding, fluorescent in-situ hybridization (FISH) and indirect and …
Microsatellite-Based Paternity Analysis In Hexaploid Sweetpotato (Ipomoea Batatas (L.) Lam.)., Mario Ignacio Buteler
Microsatellite-Based Paternity Analysis In Hexaploid Sweetpotato (Ipomoea Batatas (L.) Lam.)., Mario Ignacio Buteler
LSU Historical Dissertations and Theses
The use of genetic markers for paternity identification was investigated in hexaploid sweetpotato. Traditional sweetpotato breeding relies on the open pollination of numerous parents and the visual selection of progeny. Previous empirical and theoretical evidence shows this type of breeding system is extremely inefficient. Typically, only a few of these maternal parents routinely produce superior progeny. A similar scenario exists for the paternal parent. Identifying specific parental combinations which produce superior progeny would improve breeding efficiency, hence the need to identify paternity in superior progeny. A computer simulation study established the minimum number of alleles and loci required for paternity …
Foraging Behavior And Habitat Selection Of Insectivorous Migratory Songbirds At Gulf Coast Stopover Sites In Spring., Chao-Chieh Chen
Foraging Behavior And Habitat Selection Of Insectivorous Migratory Songbirds At Gulf Coast Stopover Sites In Spring., Chao-Chieh Chen
LSU Historical Dissertations and Theses
Abundance of some species of Nearctic-Neotropical migrants has been declining dramatically since 1970. Most literature about Neotropical migrants is from the breeding grounds, and some is from the wintering grounds; very little is from stopover sites. I studied foraging behavior and habitat selection of insectivorous migratory songbirds at three stopover sites along northern coast of the Gulf of Mexico during spring migrations of 1993-1995. Each migrant species had its unique combination of foraging behavior and habitat use during stopover. Migrants selected certain habitat strata and plant species and avoided others. The decrease of understory vegetation in the reduced plots had …