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Spatial Analysis Of The Preserved Wooden Architectural Remains Of Eight Late Classic Maya Salt Works In Punta Ycacos Lagoon, Toledo District, Belize, Bretton Michael Somers Jan 2007

Spatial Analysis Of The Preserved Wooden Architectural Remains Of Eight Late Classic Maya Salt Works In Punta Ycacos Lagoon, Toledo District, Belize, Bretton Michael Somers

LSU Doctoral Dissertations

This dissertation examined the remains of wooden architecture at eight Late Classic Maya sites found beneath the surface of Punta Ycacos Lagoon in southern Belize. The presence of briquetage on the surface and embedded among the clusters of wooden architectural features implies association with salt production activity. This research is significant in that the preservation of wooden structures at the salt works has not previously been reported for the ancient Maya. This dissertation includes a detailed discussion of documented evidence of salt production throughout Mesoamerica from archaeological, historical and modern examples. The discussion also addressed the evidence of Maya wooden …

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Forest Fragmentation Effects On Seed Dispersal, Seed Fate, And Fruit Production Of Duckeodendron Cestroides And Bocageopsis Multiflora In The Brazilian Amazon, Jennifer Mei Cramer Jan 2007

Forest Fragmentation Effects On Seed Dispersal, Seed Fate, And Fruit Production Of Duckeodendron Cestroides And Bocageopsis Multiflora In The Brazilian Amazon, Jennifer Mei Cramer

LSU Doctoral Dissertations

In tropical forests, forest fragmentation that alters species interactions between plants and animals, especially mutualisms, will affect the regeneration of trees. Fragmentation reduced Duckeodendron cestroides seed dispersal quantity and quality. The percent and distance of dispersed seeds were twice as great in continuous forest (31%, 4.9 m) as in fragments (15%, 2.5 m). Differences were even more exaggerated for each tree's furthest dispersed seeds. Distributions of dispersed seeds across distance showed more seeds at all distances in continuous forest than in fragments. Dispersal differences were strongest in years when fruit production was high and resulted in a greater number of …

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Properties Of Silica-Polypeptide Composite Particles, Jianhong Qiu Jan 2007

Properties Of Silica-Polypeptide Composite Particles, Jianhong Qiu

LSU Doctoral Dissertations

Studies of grafting polymer on surfaces with chemical bonds started in the 1970’s, but few projects have focused on grafting polypeptide on spherical particles. In this research, polypeptides poly(å-carbobenzyloxy-L-lysine) (PCBL) or poly(ã-benzyl-L-glutamate) (PBLG) were grafted on silica sphere surfaces by using the “grafting from” method. The polypeptide-grafted silica spheres are called SiPCPs. The growth of polypeptide chains as a function of monomer amount and reaction time was explored. The properties of a mixture of PBLG rod-like polymer and PBLG SiPCPs were investigated. At high concentrations of these two components, the phase behavior was studied. At low concentrations of PBLG, the …

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Environmental Factors Affecting The Distribution Of Native And Invasive Aquatic Plants In The Atchafalaya River Basin, Louisiana, U.S.A., Rachel Cathleen Walley Jan 2007

Environmental Factors Affecting The Distribution Of Native And Invasive Aquatic Plants In The Atchafalaya River Basin, Louisiana, U.S.A., Rachel Cathleen Walley

LSU Master's Theses

Over the last century, the aquatic macrophyte community of the Atchafalaya River Basin (ARB) has become increasingly dominated by invasive species. I used digital photography and GIS software to determine ARB macrophyte community composition by measuring percent cover of each plant species within five 0.25-m2 quadrats sampled from 108 sites in 2005 and 103 sites in 2006. Macrophyte community data and measurements of soil and water physicochemistry at each site were used to investigate environmental associations of the macrophytes inhabiting bayou, lake, excavated canal, and swamp habitats. Analyses indicated substantial differences in physicochemical conditions among habitats, but none of the …

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The Implantation Of Western Theatre In Korea: Hong Hae-Sǒng (1894-1957), Korea's First Director, Saejoon Oh Jan 2007

The Implantation Of Western Theatre In Korea: Hong Hae-Sǒng (1894-1957), Korea's First Director, Saejoon Oh

LSU Doctoral Dissertations

While Korea experienced the threats of imperialist powers in the 19th century, and Japanese colonial rule in the early part of the 20th century, many Korean intellectuals expressed their nationalism through efforts to implant Western culture for the modernization of the Korean nation. They believed such activities would help to realize enlightenment and industrial development, the major conditions for assuring the independence of Korea and the survival of the nation. This attitude became known as Cultural Nationalism. The establishment of modern Korean theatre participated in the movement of Cultural Nationalism. Many leaders of Korean theatre tried to implant Western modern …

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Demographic And Psychological Factors Influencing Academic Success In A College Level Human Anatomy Course, Wanda Green Hargroder Jan 2007

Demographic And Psychological Factors Influencing Academic Success In A College Level Human Anatomy Course, Wanda Green Hargroder

LSU Doctoral Dissertations

The primary purpose of this study was to determine the influence of selected demographic and psychological characteristics on the academic achievement of students enrolled in an undergraduate human anatomy course at a research-extensive university in the Southern region of the United States. As health care in the United States becomes increasingly strained due to a decreasing ratio of health care workers, educating more students to fill this gap has become a societal issue. Human anatomy forms the foundation of all health care professions. From the molecular to the macroscopic, anatomy provides a unique and necessary perspective of the human body. …

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Study Of Demolding Process In Thermal Imprint Lithography Via Numerical Simulation And Experimental Approaches, Zhichao Song Jan 2007

Study Of Demolding Process In Thermal Imprint Lithography Via Numerical Simulation And Experimental Approaches, Zhichao Song

LSU Master's Theses

The objective of present study was to analyze the mechanical behavior of polymer resist during the demolding process, such as stress distribution and evolution; distortion and tilt of microstructures in thermal imprint lithography, a new emerging technique in mass production of micro/nanoscale patterns. One of the most challenging technical issues for thermal imprint lithography is the structural damages during demolding process. Thermal stress, adhesion force and friction force all play important roles in determination of the success of demolding and it is crucial to understand the underlying physics in order to optimize the structure and process design. In present study, …

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Innovation In Teacher Education: Faculty Members' And Assessment Coordinators' Perceptions Of Electronic Assessment Systems, Dustin Michael Hebert Jan 2007

Innovation In Teacher Education: Faculty Members' And Assessment Coordinators' Perceptions Of Electronic Assessment Systems, Dustin Michael Hebert

LSU Doctoral Dissertations

Electronic assessment systems (EASs) have proliferated teacher education programs in postsecondary education. Mostly, these systems facilitate candidate and program assessment through technology-mediated procedures, allowing for greater efficiency and accuracy in data collection and analysis. If implemented successfully, the work of individuals associated with teacher education programs from faculty members to assessment coordinators and beyond has the potential to benefit from utilizing the system for course-based and programmatic assessment, both of which are criteria for the accreditation of teacher education programs by the National Council for Accreditation of Teacher Education (NCATE). This qualitative study explores the perceptions of faculty and assessment …

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The Depression Scale For Severe Disability: A Diagnostic Tool For The Assessment Of Depression In Adults With Severe And Profound Intellectual Disabilities, Christopher Cooper Jan 2007

The Depression Scale For Severe Disability: A Diagnostic Tool For The Assessment Of Depression In Adults With Severe And Profound Intellectual Disabilities, Christopher Cooper

LSU Doctoral Dissertations

The Depression Scale for Severe Disability(DEPRESSED) is a clinically and empirically derived informant-report behavioral rating scale designed to measure depression in persons with severe and profound intellectual disabilities by assessing behavioral symptoms of depression. Behavioral symptoms of depression and item and factor analyses were used to construct the scale resulting in a 20-item four-factor solution producing factors that were labeled "Sleep"(F1), "Mood"(F2), "Skills"(F3), and "Motor"(F4). The DEPRESSED identified the core symptoms of depression including mood, anhedonia, sleep, appetite, fatigue, and psychomotor agitation and retardation. Internal consistency, interrater and test-retest reliability of the DEPRESSED scale were excellent. The DEPRESSED also demonstrated …

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Manhood Constructions Among Engaged African American Male Collegians: Influences, Experiences, And Contexts, T. Elon Dancy Ii Jan 2007

Manhood Constructions Among Engaged African American Male Collegians: Influences, Experiences, And Contexts, T. Elon Dancy Ii

LSU Doctoral Dissertations

The manhood constructions and collegiate experiences of twenty-four engaged African American men enrolled across twelve, four-year colleges were explored. The purpose of this study was to inform colleges about the ways in which these men construct their manhood. The manifestations of these constructions in African American college men's behavior, enrollment, and campus engagement were also investigated. The participants, who represented a range of college engagement, were enrolled in colleges that are situated across the nineteen southern and border states of the United States of America. The institutional selection matrix was further disaggregated according to predominant population (HBCU, HWI) and institutional …

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Brucella Melitensis: The Evaluation Of A Putative Hemagglutinin Gene's Effect On Virulence In The Caprine Model, Quinesha Laticia Perry Jan 2007

Brucella Melitensis: The Evaluation Of A Putative Hemagglutinin Gene's Effect On Virulence In The Caprine Model, Quinesha Laticia Perry

LSU Doctoral Dissertations

Brucella melitensis is a facultative intracellular bacterial pathogen that causes abortions in goats and sheep and Malta fever in humans. The zoonotic disease brucellosis causes severe economic losses in the Mediterranean region and parts of Africa, Asia, and Latin America. With the completion of the genomic sequences of B. abortus 2308 and B. melitensis 16M, no classical virulence factors were found; and the chromosomes were virtually identical. However, in B. melitensis, a putative hemagglutinin gene was identified which is absent in B. abortus. The possibility of the hemagglutinin gene being a potential virulence factor was evaluated via gene replacement/deletion in …

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Assessment Of Thelypteris Palustris, Asparagus Sprengeri, And Lolium Perenne For Their Potential Use In The Phytoremediation Of Arsenic-Contaminated Soils, Lashunda L. Anderson Jan 2007

Assessment Of Thelypteris Palustris, Asparagus Sprengeri, And Lolium Perenne For Their Potential Use In The Phytoremediation Of Arsenic-Contaminated Soils, Lashunda L. Anderson

LSU Doctoral Dissertations

The goal of this study is to evaluate the potential of three plants, Thelypteris palustris (marsh fern), Asparagus sprengeri (asparagus fern), and Lolium perenne (perennial ryegrass) for use in phytoremediation of arsenic-contaminated soils. Specifically, the objectives of this study are to (1) confirm if arsenic accumulation occurs in the selected plants, (2) to examine morphological effects of arsenic in the selected plants, and (3) to evaluate the oxidation state of arsenic upon accumulation in the selected plants. The analytical method combination of ICP-MS, SEM, and XANES was used to accomplish the objectives of this study. The results indicate marsh fern, …

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Experimental And Modeling Studies Of Contaminant Transport In Capped Sediments During Gas Bubble Ebullition, Qingzhong Yuan Jan 2007

Experimental And Modeling Studies Of Contaminant Transport In Capped Sediments During Gas Bubble Ebullition, Qingzhong Yuan

LSU Doctoral Dissertations

Fluxes of the three organics and eighteen metals from sediments were measured with diffusion chambers, and the effectiveness of a sand cap ascertained. The influence of sediment consolidation on contaminant flux and the mass transfer coefficient at the sediment-water interface was studied. A two-layer diffusion-advection model and consolidation model were coupled to elucidate the effect of sediment consolidation on chemical transport in the sediment-cap system. The model was tested and verified by the experimental data from microcosms, and then was used to predict phenanthrene flux under field conditions. The simulation results showed that consolidation could accelerate phenanthrene breakthrough and enhance …

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Modeling Spatial And Temporal Variations Of Surface Moisture Content And Groundwater Table Fluctuations On A Fine-Grained Beach, Padre Island, Texas, Yuanda Zhu Jan 2007

Modeling Spatial And Temporal Variations Of Surface Moisture Content And Groundwater Table Fluctuations On A Fine-Grained Beach, Padre Island, Texas, Yuanda Zhu

LSU Doctoral Dissertations

The basic goals of this study are to document, represent and model beach surface moisture dynamics. Achieving these goals requires that the dynamics be understood within the context of the key associated processes including evaporation and groundwater table fluctuations. Atmospheric parameters including wind speed, air temperature and relative humidity, evaporation, beach surface moisture content, groundwater table fluctuations and tidal oscillations were directly monitored in an eight-day field experiment. Field measurements demonstrated that beach surface moisture content has a relatively high degree of variability in the cross-shore direction and a relatively low variability in the alongshore direction. The highest levels of …

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Measuring Skeletal Kinematics With Accelerometers On The Skin Surface, Kevin Curtis Ayer Jan 2007

Measuring Skeletal Kinematics With Accelerometers On The Skin Surface, Kevin Curtis Ayer

LSU Master's Theses

The most common motion analysis method uses cameras to track the position of markers on bodily surfaces over time. Although each species has a common skeletal frame to reference recorded motions, the soft tissue covering each is not rigid. Markers, therefore, experience motion relative to the bone and do not accurately portray underlying bone activity. This limits clinical use of motion studies and the understanding of joint motion. Use of MEMS accelerometers for removing soft tissue artifact, motion relative to the bone, from surface measurements and determining the position of the underlying bone was investigated. An animal limb was modeled …

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Use Of Dendrochronology To Promote Understanding Of Environmental Change, Cynthia Stager Mccormick Jan 2007

Use Of Dendrochronology To Promote Understanding Of Environmental Change, Cynthia Stager Mccormick

LSU Doctoral Dissertations

The purpose of this research was to determine how dendrochronology can be used in an experiential unit to enhance high school students’ understanding of environmental change. Dendrochronology, the visual examination of tree ring cross sections provides opportunities to relate environmental change to growth patterns of trees and can be used to show the students both how scientists can investigate the past and how the environment can affect trees. Students engaged in a 10-day unit that employed a variety of constructivist learning activities to investigate environmental change, climate change, and tree growth. The culminating activity was student-created experiments that investigated various …

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Comparison Of Middle School Student Performance On Photograph-Based Multiple-Choice Items And Text-Based Multiple-Choice Items On A State Science Achievement Test, Susannah Fowler Craig Jan 2007

Comparison Of Middle School Student Performance On Photograph-Based Multiple-Choice Items And Text-Based Multiple-Choice Items On A State Science Achievement Test, Susannah Fowler Craig

LSU Doctoral Dissertations

The purpose of this study was to investigate how photograph-based life science multiple-choice items influenced Louisiana science students' performance on statewide standardized tests, in comparison with text-based items about the same content. This mixed methodology research study focused primarily on types of multiple-choice items, specifically five matched pairs of multiple-choice items, text-only and same-text with a photograph. For the 2007 LEAP field test, statistics from 11 multiple-choice items were utilized to characterize student performance on photograph-based multiple-choice items. Data from all Louisiana 8th grade students taking Form 3 (n=1130) and Form 4 (n=1182) were analyzed to compare student performance on …

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Measurements And Computations Of The Flow In Full-Scale Sugar Evaporative-Crystallizers And In Lab-Scale Models, Luis Fernando Echeverri Jan 2007

Measurements And Computations Of The Flow In Full-Scale Sugar Evaporative-Crystallizers And In Lab-Scale Models, Luis Fernando Echeverri

LSU Doctoral Dissertations

The circulation of massecuite is a key factor in achieving efficient heat transfer and crystallization in sugar evaporative crystallizers, and should be as high as practically possible for recovery, quality, and capacity reasons. This research report presents results on the circulation obtained applying modern experimental and numerical techniques. The main goals are contributing to expand the understanding of the process in sugar crystallizers; developing realistic models for the simulation of the circulation; and studying the effect of different design parameters. The circulation of massecuite is driven by buoyancy force due to density difference between the vapor generated and the surrounding …

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Establishment And Chemical Analysis Of Hairy Roots Of Eucommia Ulmoides, Xiaojun Wu Jan 2007

Establishment And Chemical Analysis Of Hairy Roots Of Eucommia Ulmoides, Xiaojun Wu

LSU Doctoral Dissertations

The bark of Eucommia ulmoides Oliver (Eucommiaceae) has been used over thousands of years as a folk remedy. Extracts from the bark exhibit multiple pharmacological functions, especially in lowering blood pressure. Geniposidic acid (GA), pinoresinol diglucoside (PG) and chlorogenic acid (CA) are three compounds isolated from the bark of the Eucommia tree, which display enormous bioactivities. As a type of plant tissue culture, the hairy root culture system displays prospective application over traditional cell or callus cultures, which are characterized by rapid growth, and stable biochemical and genetic capacity. The present dissertation discusses the establishment and chemical analysis of E. …

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Exploring The Binding Of Amine And Sulfonamide Ligands In Rhenium(I) Tricarbonyl And Platinum(Ii) Complexes, Anna Maria Christoforou Jan 2007

Exploring The Binding Of Amine And Sulfonamide Ligands In Rhenium(I) Tricarbonyl And Platinum(Ii) Complexes, Anna Maria Christoforou

LSU Doctoral Dissertations

Platinum is the metal present in various classes of inorganic medicinal agents directed at important diseases such as cancer or viral infections. Several new Pt(II) complexes of polyamine ligands bearing a dansyl moiety linked by a sulfonamide group were prepared; in some cases the sulfonamide nitrogen formed a bond to Pt. The sulfonamido group donates strongly to Pt and places the dansyl group close to a vacant coordination position, allowing it to stack with bound guanine base (G) when G binds. The emission of the fluorophore decreases with decreasing distance to Pt. Metal nuclide radiopharmaceuticals contain a metal core and …

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Community College Students' Plant Biodiversity Learning Experience In An Introductory Biology Course: Exploring The Value Added By Using A Cd-Rom To Develop Inquiry Lessons, Sandra M. Guzman-Rodriguez Jan 2007

Community College Students' Plant Biodiversity Learning Experience In An Introductory Biology Course: Exploring The Value Added By Using A Cd-Rom To Develop Inquiry Lessons, Sandra M. Guzman-Rodriguez

LSU Doctoral Dissertations

This study examined the value added to standard textbook-based instruction of plant biodiversity by the use of the exemplary interactive CD-ROM, Conserving Earth’s Biodiversity. This CD-ROM features renowned conservation figure E.O. Wilson. The setting of the research was an introductory biology course in a rural public community college in the Deep South. Six participants were purposively selected to represent three levels of achievement and two groups, the CD-ROM group (exposed to CD-ROM in addition to the textbook) and the textbook group (only course textbook). Students experienced lecture-based, textual, virtual, and real experiences, and examined their ability to understand biodiversity-related concepts …

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Genetics Of Herpes Simplex Virus Type-1 Tegument Proteins Involved In Virion Morphogenesis And Egress, Preston A. Fulmer Jan 2007

Genetics Of Herpes Simplex Virus Type-1 Tegument Proteins Involved In Virion Morphogenesis And Egress, Preston A. Fulmer

LSU Doctoral Dissertations

Herpes simplex virus type-1 (HSV-1) morphogenesis occurs in multiple stages within infected cells. Initially, the virion capsid assembles within the nucleus and buds through the nuclear membrane into the cytoplasm. Within the cytoplasm, additional tegument proteins attach to the capsid and the fully tegumented capsids bud into trans-Golgi network (TGN) derived vesicles. Enveloped virions are ultimately secreted to extracellular spaces. The process by which the cytoplasmic capsids bud into TGN-derived vesicles is not well understood. The prevalent model calls for specific interactions among viral tegument proteins and membrane proteins and glycoproteins embedded within TGN membranes. To further investigate the roles …

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Probing The Association Behavior Of Hydrophobic Organic Compounds With Dissolved Humic Materials, Hadi M. Marwani Jan 2007

Probing The Association Behavior Of Hydrophobic Organic Compounds With Dissolved Humic Materials, Hadi M. Marwani

LSU Doctoral Dissertations

The association mechanism between hydrophobic organic compounds (HOC) and dissolved humic materials (DHM) has continued to be one of the interesting areas in environmental applications. The goal of the research reported in this dissertation is to investigate the association behavior of HOC with DHM. The first part of this research involves steady-state fluorescence measurements of these multi-component systems to study the effect of DHM content on the association mechanism of HOC, in particular using pyrene as a model. Results showed that steady-state fluorescence alone may not provide enough information about the quenching mechanism of pyrene with DHM. Lifetime based fluorescence …

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Analysis Of The Association Between Socio-Demographic Variables, Juvenile Offending, And Formal Vs. Informal Juvenile Justice System Handling In A Non-Urban Sample, Stephen W. Phillippi, Jr. Jan 2007

Analysis Of The Association Between Socio-Demographic Variables, Juvenile Offending, And Formal Vs. Informal Juvenile Justice System Handling In A Non-Urban Sample, Stephen W. Phillippi, Jr.

LSU Doctoral Dissertations

PURPOSE: This study compares and contrasts first-time juvenile offenders enrolled in a community-based intervention program whose cases were processed either informally or formally, and examines empirically- and conceptually-relevant contributors to re-offending. METHODS: This is a longitudinal, secondary analysis of 1072 male and female offenders. The study includes descriptive univariate analyses; chi-square bivariate analyses of each independent variable with the dependent variables (level of processing and recidivism at both one and three years); and binary logistic regression analyses to identify significant predictors of the dependent variables. Independent variables include age, gender, race, family structure, marital status of biological parents, family income, …

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The Influence Of Values And Other Social And Psychological Factors On The Dress And Appearance Of African American College Students, Devona Linette Dixon Jan 2007

The Influence Of Values And Other Social And Psychological Factors On The Dress And Appearance Of African American College Students, Devona Linette Dixon

LSU Doctoral Dissertations

The purpose of the study was to investigate values and other social and psychological factors influence on dress and appearance of African American college students (AACS). The dependent variable was dress and appearance. Independent variables consisted of external values (being well-respected, security, warm relationships with others, and sense of belonging) and internal values (self-respect, sense of accomplishment, fun and enjoyment, self-fulfillment, and excitement). Included in the independent variables were social factors (media and referents' influence (peers and family)) and psychological factors (self-consciousness, self-confidence, fashion leadership, and shopping enjoyment). Social adaptation theory provided the theoretical framework. The theory encompasses the social …

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Spatial Econometric Analysis Of Agglomeration Economies Associated With The Geographical Distribution Of The U.S. Biotech Industry, Pramod Reddy Sambidi Jan 2007

Spatial Econometric Analysis Of Agglomeration Economies Associated With The Geographical Distribution Of The U.S. Biotech Industry, Pramod Reddy Sambidi

LSU Doctoral Dissertations

This dissertation analyzed spatial agglomeration economies associated with the geographical distribution of the U.S. biotech industry. Three location issues associated with the biotech industry were addressed in the study. The first study utilized a Bayesian spatial tobit model and examined the overall and regional differences in factors affecting the location of the U.S. biotech industry. The second study examined the inter- and intra-industry spatial association of biotech related research and development (R&D) and testing facilities across all contiguous U.S. counties employing a Spatial Two-Stage Least Squares model. Finally, the interdependence between different subsectors of the U.S. biotech industry was analyzed …

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Isolation And Characterization Of The Siamese Family: A Novel Class Of Cell Cycle Regulators In Plants, Michelle Lynn Churchman Jan 2007

Isolation And Characterization Of The Siamese Family: A Novel Class Of Cell Cycle Regulators In Plants, Michelle Lynn Churchman

LSU Doctoral Dissertations

Recessive mutations in the SIAMESE (SIM) gene of Arabidopsis result in multicellular trichomes harboring individual nuclei with a low ploidy level, a phenotype strikingly different from that of wild-type trichomes, which are single cells with a nuclear DNA content of approximately 16-32C. These observations suggested that SIM is required to suppress mitosis as part of the switch to endoreplication in trichomes. We demonstrate that SIM encodes a novel 14kD protein that is part of a small Arabidopsis gene family comprised of four members. Homologs exist in other dicots and in monocots, although no obvious animal homologs have been identified. SIM …

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Culture-Independent Identification Of Gut Bacteria In Fourth-Instar Red Imported Fire Ant, Solenopsis Invicta Buren, Larvae, Albert Hon-Yu Lee Jan 2007

Culture-Independent Identification Of Gut Bacteria In Fourth-Instar Red Imported Fire Ant, Solenopsis Invicta Buren, Larvae, Albert Hon-Yu Lee

LSU Doctoral Dissertations

Red imported fire ants (RIFA), Solenopsis invicta Buren, are medical, urban, and agricultural pests from South America. Fourth-instar larvae are used by the colony to digest solid food and then regurgitate it for consumption by workers and queens. Larvae are an ideal source of investigations of obligate endosymbiotic bacteria possibly involved in nutrient distributions. I attempted to first identify what bacteria species are in the guts of larvae followed by antibiotic and microscopy work to further study their roles in the ants. The composition of the bacterial community in fire ant larvae was described with culture-independent methods utilizing 16S rDNA …

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Watershed-Scale Patterns Of Seaward Migration In Lentipes Concolor, A Hawaiian Stream Goby, Mark Gordon Mcrae Jan 2007

Watershed-Scale Patterns Of Seaward Migration In Lentipes Concolor, A Hawaiian Stream Goby, Mark Gordon Mcrae

LSU Doctoral Dissertations

The native stream fishes of the Hawaiian Islands are uniquely adapted to colonize and thrive in lotic habitats in this extremely isolated archipelago. Chapter 1 of this dissertation introduces the five native fishes of Hawaii's streams and describes the variety of lotic habitats they occupy. All five species have amphidromous life cycles, and, as such, their larvae must migrate to the ocean soon after hatching. Of the five species, Lentipes concolor is able to scale Hawaii’s highest waterfalls during the migration back into fresh water, and therefore inhabits the widest variety of stream types. Adult L. concolor are found a …

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Population Ecology Of Pseudacteon Tricuspis Borgmeier (Diptera: Phoridae), An Introduced Parasitoid Of The Red Imported Fire Ant Solenopsis Invicta Buren (Hymenoptera: Formicidae) In Louisiana, Donald Charles Henne Jan 2007

Population Ecology Of Pseudacteon Tricuspis Borgmeier (Diptera: Phoridae), An Introduced Parasitoid Of The Red Imported Fire Ant Solenopsis Invicta Buren (Hymenoptera: Formicidae) In Louisiana, Donald Charles Henne

LSU Doctoral Dissertations

Aspects of the population ecology of a parasitoid (Pseudacteon tricuspis) of the red imported fire ant (Solenopsis invicta) in Louisiana were studied. The spatio-temporal abundance patterns, dispersal, population spread, aggregation, direct mutual interference and functional response characteristics of this parasitoid were studied to address deficiencies in our knowledge about phorid flies, particularly Pseudacteon parasitoids. This endoparasitoid was discovered to manipulate host ant behavior in ways that benefit its own survival. Laboratory experiments to gain insights into behavioral and functional responses revealed that fly aggregations were density-dependent and interference was not significant when 1-3 females were simultaneously confined with hosts, although …

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