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2012

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Rural–Urban Differences In Dental Service Use Among Children Enrolled In A Private Dental Insurance Plan In Wisconsin: Analysis Of Administrative Data, Pradeep Bhagavatula, Qun Xiang, Aniko Szabo, Fredrick Eichmiller, Raymond A. Kuthy, Christopher Okunseri Jan 2012

Rural–Urban Differences In Dental Service Use Among Children Enrolled In A Private Dental Insurance Plan In Wisconsin: Analysis Of Administrative Data, Pradeep Bhagavatula, Qun Xiang, Aniko Szabo, Fredrick Eichmiller, Raymond A. Kuthy, Christopher Okunseri

School of Dentistry Faculty Research and Publications

Background

Studies on rural–urban differences in dental care have primarily focused on differences in utilization rates and preventive dental services. Little is known about rural–urban differences in the use of wider range of dental procedures. This study examined patterns of preventive, restorative, endodontic, and extraction procedures provided to children enrolled in Delta Dental of Wisconsin (DDWI).

Methods

We analyzed DDWI enrollment and claims data for children aged 0-18 years from 2002 to 2008. We modified and used a rural and urban classification based on ZIP codes developed by the Wisconsin Area Health Education Center (AHEC). We categorized the ZIP codes …


Discrepancies Between Abstracts Presented At International Association For Dental Research Annual Sessions From 2004 To 2005 And Full-Text Publication, Soni Prasad, Damian J. Lee, Judy Chia-Chun Yuan, Valentim A. R. Barao, Nodesh Shyamsunder, Cortino Sukotjo Jan 2012

Discrepancies Between Abstracts Presented At International Association For Dental Research Annual Sessions From 2004 To 2005 And Full-Text Publication, Soni Prasad, Damian J. Lee, Judy Chia-Chun Yuan, Valentim A. R. Barao, Nodesh Shyamsunder, Cortino Sukotjo

School of Dentistry Faculty Research and Publications

Purpose. The purpose of this study was to evaluate the discrepancies between abstracts presented at the IADR meeting (2004-2005) and their full-text publication. Material and Methods. Abstracts from the Prosthodontic Section of IADR meeting were obtained. The following information was collected: abstract title, number of authors, study design, statistical analysis, outcome, and funding source. PubMed was used to identify the full-text publication of the abstracts. The discrepancies between the abstract and the full-text publication were examined, categorized as major and minor discrepancies, and quantified. The data were collected and analyzed using descriptive analysis. Frequency and percentage of major …


Improved Potential Energy Surface Of Ozone Constructed Using The Fitting By Permutationally Invariant Polynomial Function, M. Ayouz, Dmitri Babikov Jan 2012

Improved Potential Energy Surface Of Ozone Constructed Using The Fitting By Permutationally Invariant Polynomial Function, M. Ayouz, Dmitri Babikov

Chemistry Faculty Research and Publications

New global potential energy surface for the ground electronic state of ozone is constructed at the complete basis set level of the multireference configuration interaction theory. A method of fitting the data points by analytical permutationally invariant polynomial function is adopted. A small set of 500 points is preoptimized using the old surface of ozone. In this procedure the positions of points in the configuration space are chosen such that the RMS deviation of the fit is minimized. New ab initio calculations are carried out at these points and are used to build new surface. Additional points are added to …


Chemical Crystallography At The Interface Of Physics, Chemistry, And In Engineering: Structure Determination Of Highly Correlated Extended Solids, Main Group Compounds, Coordination Complexes, And Bioceramics, Gregory Todd Mccandless Jan 2012

Chemical Crystallography At The Interface Of Physics, Chemistry, And In Engineering: Structure Determination Of Highly Correlated Extended Solids, Main Group Compounds, Coordination Complexes, And Bioceramics, Gregory Todd Mccandless

LSU Doctoral Dissertations

Multi-disciplinary research is essential to address the major challenges in science, engineering, and medicine. For these three areas, crystallography has played and continues to play a huge role by providing researchers with the means to determine the structure of a compound and relate these to its properties. This dissertation is highly interdisciplinary, focusing on structure determination of complex systems and materials with tailored applications. This work includes the characterization by single crystal and powder X-ray diffraction of intermetallic extended solids, layered metal oxides, inorganic complexes, discrete organic molecules, and bioceramics. These projects range from modeling translational disorder with pseudo-hexagonal symmetry …


Hierarchical Linear Modeling Versus Visual Analysis Of Single Subject Design Data, Elizabeth Godbold Nelson Jan 2012

Hierarchical Linear Modeling Versus Visual Analysis Of Single Subject Design Data, Elizabeth Godbold Nelson

LSU Doctoral Dissertations

Visual analysis is the “gold standard” for single-subject design data because of a presumed low Type I error rate and consistency across raters. However, research has found it less accurate and reliable than typically assumed. Many statistics have been proposed as aids for visual analysis, but most suffer from limitations either due to methods of investigation or problems inherent to the statistics themselves. Several researchers have proposed the use of Hierarchical Linear Modeling to analyze single-subject data because it can withstand violations of assumptions often present in single-subject data that other statistics cannot. In addition, HLM is similar to the …


Diversity Of Yeasts Associated With Wood And The Gut Of Wood-Feeding Insects, Hector Raul Urbina Jan 2012

Diversity Of Yeasts Associated With Wood And The Gut Of Wood-Feeding Insects, Hector Raul Urbina

LSU Doctoral Dissertations

The gut of insects and plant tissues are productive sources for the isolation of undescribed species of yeasts. In particular, the gut of lignicolous insects is colonized by yeasts that can carry out the fermentation of several sugars. The consistent association between xylose-fermenting (X-F) yeasts and the gut of lignicolous insects has been used as evidence of a symbiotic relationship between them. In general passalid beetles (Passalidae) and wood-roaches (Cryptocercidae) feed on rotted wood where they spend most of their lives. Digestion of the substrate depends on the symbiotic microbiota, which include strict and facultative anaerobic microorganisms such as bacteria, …


Development Of Hydrograph-Based Approach To Modeling Fate And Transport Of Sediment-Borne Bacteria In Lowland Rivers, Bhuban Ghimire Jan 2012

Development Of Hydrograph-Based Approach To Modeling Fate And Transport Of Sediment-Borne Bacteria In Lowland Rivers, Bhuban Ghimire

LSU Doctoral Dissertations

Fecal pollution is one of the major factors responsible for water quality impairments of rivers and streams, particularly organic-rich fine-grained lowland streams. While predicting fecal pollution is generally required in the development of water quality restoration plans like Total Maximum Daily Loads, no single model has been widely recognized as an efficient and effective tool for estimating fecal pollution. This dissertation develops a simple yet effective modeling approach, called Hydrograph-based Approach, to bacterial fate and transport modeling in lowland rivers. The new hydrograph-based approach is simple and efficient in terms of its less data requirements as compared with other models. …


Examination Of The Reliability And Validity Of A New Observation Measure For Autism Spectrum Disorders: The Autism Spectrum Disorder Observation For Children, Daniene Neal Jan 2012

Examination Of The Reliability And Validity Of A New Observation Measure For Autism Spectrum Disorders: The Autism Spectrum Disorder Observation For Children, Daniene Neal

LSU Doctoral Dissertations

With increasing attention being drawn to autism spectrum disorders (ASD), specifically with regard to early and accurate diagnosis and treatment, researchers and clinicians alike have placed emphasis on finding assessment tools that can aid in this goal. The purpose of this study is to examine the psychometric properties of a new observation measure for ASD, the Autism Spectrum Disorders-Observation for Children (ASD-OC). The ASD-OC was found to have good to excellent interrater reliability, and excellent internal consistency (ƒÑ = .96). As a result of these initial reliability analyses, nine items were removed from the scale. The resulting 45 item ASD-OC …


Microfabrication Of Conductive Polymer Nanocomposite For Sensor Applications, Chaoxuan Liu Jan 2012

Microfabrication Of Conductive Polymer Nanocomposite For Sensor Applications, Chaoxuan Liu

LSU Doctoral Dissertations

This dissertation developed novel microfabrication techniques of conductive polymer nanocomposite and utilized this material as a functional element for various physical sensor applications. Microstructures of nanocomposite were realized through novel microcontact printing and laser ablation assisted micropatterning processes. Prototype devices including large-strain strain sensor and highly-sensitive pressure sensor were demonstrated showing distinct advantages over existing technologies. The polymer nanocomposite used in this work comprised elastomer poly(dimexylsiloxane) (PDMS) as polymer matrix and multi-walled carbon nananotubes (MWCNTs) as a conductive nanofiller. To achieve uniform distribution of carbon nanotubes within the polymer, an optimized dispersion process was developed, featuring a strong organic solvent—chloroform, …


Hypercube Diagrams For Knots, Links, And Knotted Tori, Ben Mccarty Jan 2012

Hypercube Diagrams For Knots, Links, And Knotted Tori, Ben Mccarty

LSU Doctoral Dissertations

For a knot K the cube number is a knot invariant defined to be the smallest n for which there is a cube diagram of size n for K. Examples of knots for which the cube number detects chirality are presented. There is also a Legendrian version of this invariant called the Legendrian cube number. We will show that the Legendrian cube number distinguishes the Legendrian left hand torus knots with maximal Thurston-Bennequin number and maximal rotation number from the Legendrian left hand torus knots with maximal Thurston-Bennequin number and minimal rotation number. Finally, there is a generalization of cube …


An Investigation Into The Moderating Role Of Fear Appeals On The Relationship Between Regulatory Fit And Persuasion, Nam Young Kim Jan 2012

An Investigation Into The Moderating Role Of Fear Appeals On The Relationship Between Regulatory Fit And Persuasion, Nam Young Kim

LSU Doctoral Dissertations

As one of the ways to persuade young people effectively, several scholars have indicated that using a tailored message that is consistent with individuals’ concerns and interests can influence their attitude and behavioral changes. Among diverse tactics to construct tailored health-messages, this research especially paid attention to individuals’ motivational goals (i.e., regulatory focus) that make them more inclined to a certain outcome. While promotion-oriented individuals primarily focus on how to achieve a desired ending, prevention-oriented individuals mainly focus on avoiding undesirable outcomes (Higgins, 1997; Higgins et al., 2001). Although numerous studies support the positive effects of the congruency between regulatory …


Online Reviews And Consumers' Willingness To Pay: The Role Of Uncertainty, Yinglu Wu Jan 2012

Online Reviews And Consumers' Willingness To Pay: The Role Of Uncertainty, Yinglu Wu

LSU Doctoral Dissertations

Empirical studies of online reviews have found that valence (average rating) has a consistently positive impact on consumers’ willingness to pay (WTP), but volume does not. Although two studies tried to explain this phenomenon using different perspectives (Wu and Ayala, 2012; Sun, 2012), neither study can fully accommodate the consumer behaviors observed by the other. This dissertation adopts a theoretical framework that can explain the consumer behaviors observed in both studies as well as the varying influence of review volume at the individual level. Specifically, several studies were conducted to investigate the relationship between bidirectional online seller reviews (e.g., the …


Intra-Individual Variability In Adult Adhd: An Exploration Of The Viability Of Distinct Purely Inattentive Condition, Daniel Proto Jan 2012

Intra-Individual Variability In Adult Adhd: An Exploration Of The Viability Of Distinct Purely Inattentive Condition, Daniel Proto

LSU Doctoral Dissertations

Researchers have suggested that intraindividual variability (IIV), or variation in cognitive testing performance within an individual across a measure or group of measures, may be an endophenotypic marker of Attention-Deficit/Hyperactivity Disorder (ADHD). However, not all studies have consistently demonstrated significant differences in IIV between individuals with and without ADHD. One potential explanation for this ambiguity is experimental group heterogeneity owing to Sluggish Cognitive Tempo (SCT). Individuals with SCT exhibit behavioral characteristics dissimilar from individuals with ADHD; rather than being impulsive, hyperactive, and aggressive, they tend to be shy, day-dreamy, and cognitively slow. Researchers have hypothesized that the presence of SCT …


Global And Local Performance Of Prestressed Girder Bridges With Positive Moment Continuity Detail, Tanvir Hossain Jan 2012

Global And Local Performance Of Prestressed Girder Bridges With Positive Moment Continuity Detail, Tanvir Hossain

LSU Doctoral Dissertations

Global as well as local behavior of prestressed girder bridges made continuous by adding continuity diaphragms with a recently proposed positive moment continuity detail were investigated in this study. The focus of the investigation is on the positive moment caused by temperature gradients, time dependent effects such as creep and shrinkage, and some live load positions, and on the force transfer mechanisms through the diaphragm. The study utilized different approaches including analytical models for temperature evaluations and finite element models for structural assessments. Field data from a bridge using the new detail were used to validate the developed models. The …


Early Voting In The 2004 Presidential Election, James Michael Siira Jan 2012

Early Voting In The 2004 Presidential Election, James Michael Siira

LSU Doctoral Dissertations

The addition of early voting laws has led to the many changes in the US political system. In this dissertation I examine early voting early voting in a number of different contexts. First, how early voting fits in with the larger issue of voter turnout in the U.S. Second, why some states have early voting policies and other states choose to not have those policies. Third, how state-level political parties view the option to cast an early vote. Fourth, the differences between early voters, election day voters, and non-voters. Fifth, what are the determents of casting an early ballot. Sixth, …


Comparing Symptoms Of Autism Spectrum Disorders Using The Current Dsm-Iv-Tr Diagnostic Criteria And The Proposed Dsm-V Diagnostic Criteria, Julie A. Worley Jan 2012

Comparing Symptoms Of Autism Spectrum Disorders Using The Current Dsm-Iv-Tr Diagnostic Criteria And The Proposed Dsm-V Diagnostic Criteria, Julie A. Worley

LSU Doctoral Dissertations

Children diagnosed with Autistic Disorder (AD), Asperger’s Disorder (AS), and Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) share overlapping diagnostic criteria. As a result, there has been an enduring debate regarding the appropriateness of the current categorical classification system used to diagnose this group of disorders, commonly referred to as Autism Spectrum Disorders (ASD). Ongoing research examining the boundaries of the disorders comprising the spectrum have yielded inconsistent findings in symptom differences; therefore, the American Psychiatric Association has proposed revisions for the upcoming version of the Diagnostic and Statistical Manual of Mental Disorders (i.e., DSM-5). Revisions include dropping all subcategories …


How Faith And Leadership Are Connected: A Study Of Catholic Women Administrators In A Southern Public Institution Of Higher Education, Mary Blanchard Wallace Jan 2012

How Faith And Leadership Are Connected: A Study Of Catholic Women Administrators In A Southern Public Institution Of Higher Education, Mary Blanchard Wallace

LSU Doctoral Dissertations

Studies concerning spirituality and higher education, particularly for the college student, are beginning to appear in journals, conference papers, and presentations. However, there is little research conducted with professionals in higher education on the construct of spirituality. Spirituality has so many different definitions in the literature, it is difficult to define, and perhaps even more complex to study academically. Using a research-based conceptual model for religious faith, developed within the study of family sciences, this study examines the lived experience of how and why Catholic women administrators connect their faith and leadership in a setting of public institutions of higher …


Evaluation Of The Thermal Performance And Cost Effectiveness Of Radiant Barrier Thermal Insulation Materials In Residential Construction, Somayeh Asadi Jan 2012

Evaluation Of The Thermal Performance And Cost Effectiveness Of Radiant Barrier Thermal Insulation Materials In Residential Construction, Somayeh Asadi

LSU Doctoral Dissertations

Reducing heating and cooling systems loads in buildings is a cost effective way to decrease energy consumption in residential houses. This reduction can be achieved in many ways including proper insulation of the building envelope. In recent years, considerable attention was given to the use of radiant reflective insulating barriers. Over the past years, reflective barrier insulation companies nationwide have experienced significant growth resulting in an industry average growth rate of 26.8%. This significant growth is expected to continue as a result of increased cooling demands and pressure from the energy sector and the economy. Growth is also predicted to …


A Thermodynamic Framework For The Modeling And Optimization Of Crystallization Processes, David John Widenski Jan 2012

A Thermodynamic Framework For The Modeling And Optimization Of Crystallization Processes, David John Widenski

LSU Doctoral Dissertations

Crystallization is a widely used chemical engineering separation unit operation process. Since this technique can produce high purity products it is used for the industrial production of many chemical compounds, such as pharmaceuticals, agrochemicals, and fine chemicals. The production of these products is a multi-million dollar industry. Any methods to improve the production of these products would be highly valued. Thus, the main objective of this work is to target model-based optimal strategies for crystallization operations specifically targeting crystal size and crystal size distribution (CSD). In particular, take the knowledge gained and translate it into an economically and practically feasible …


On The Synthesis, Characterization, And Magnetization Of Ln-M-X (Ln = Lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) Intermetallics, Michael James Kangas Jan 2012

On The Synthesis, Characterization, And Magnetization Of Ln-M-X (Ln = Lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) Intermetallics, Michael James Kangas

LSU Doctoral Dissertations

The focus of the research presented herein was to grow single crystals of Ln-M-X (Ln = lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) intermetallic compounds and to characterize their crystal structures and physical properties. Overall, the flux growth technique facilitated a detailed analysis of previously known structure-types (LnM2Al20 (Ln = La, Ce, Pr, Yb; M = Ti, V, Cr), Ln6M4Al43 (Ln = Gd, Yb; M = Cr, Mo), and Yb2Pd3Ga9), as well as the synthesis and characterization of new compounds (LnCrxGa3 (Ln = Ho, Er; x ~ 0.13), YbCr2Al20-xFex (x ~ 0.2), Ln(Cu,Al,Ga)13-x, and Ln2PdGa12 (Ln …


Low Temperature Carbon Material Deposition With Photo-Enhanced Chemical Vapor Deposition, Kyungnam Kang Jan 2012

Low Temperature Carbon Material Deposition With Photo-Enhanced Chemical Vapor Deposition, Kyungnam Kang

LSU Doctoral Dissertations

Photo-enhanced chemical vapor deposition (CVD) technique is investigated here for low temperature deposition of carbon nanotubes (CNTs) and hexagonal diamond. Most current deposition methods require high substrate temperature. Photo-enhanced CVD utilizes light energy to dissociate carbon containing precursor molecules and hence has a potential for low temperature deposition. CCl4, having a high absorption coefficient compared to other commonly employed hydrocarbons in the UV emission spectrum from a Xe arc lamp, is selected as a carbon precursor in this work. Extensive experimentation conducted by varying Al/Ni/Al catalyst layer thicknesses on SiO2 coated Si substrates, substrate annealing temperature in the range 350 …


Visualization Of Time-Varying Data From Atomistic Simulations And Computational Fluid Dynamics, Bidur Bohara Jan 2012

Visualization Of Time-Varying Data From Atomistic Simulations And Computational Fluid Dynamics, Bidur Bohara

LSU Doctoral Dissertations

Time-varying data from simulations of dynamical systems are rich in spatio-temporal information. A key challenge is how to analyze such data for extracting useful information from the data and displaying spatially evolving features in the space-time domain of interest. We develop/implement multiple approaches toward visualization-based analysis of time-varying data obtained from two common types of dynamical simulations: molecular dynamics (MD) and computational fluid dynamics (CFD). We also make application case studies. Parallel first-principles molecular dynamics simulations produce massive amounts of time-varying three-dimensional scattered data representing atomic (molecular) configurations for material system being simulated. Rendering the atomic position-time series along with …


Applicability Of Periodization To Orchestral Audition Preparation On Trombone: A Case Study, Christopher Evan Green Jan 2012

Applicability Of Periodization To Orchestral Audition Preparation On Trombone: A Case Study, Christopher Evan Green

LSU Doctoral Dissertations

The process of auditioning can seem daunting because of the high standards of performance required to win. Brass players have a finite amount of time they can practice each day because of the small muscles of the embouchure. Despite the vast amount of information available on preparing for a brass orchestral audition, little has been written on how to organize a practice schedule leading up to the audition. An analysis of literature in the major brass journals confirm which strategies have been considered to be most important when preparing for an audition, but an important component from the world for …


Linking Nitrogen Biogeochemistry To Different Stages Of Wetland Soil Development In The Mississippi River Delta, Louisiana, Kelly Marie Henry Jan 2012

Linking Nitrogen Biogeochemistry To Different Stages Of Wetland Soil Development In The Mississippi River Delta, Louisiana, Kelly Marie Henry

LSU Doctoral Dissertations

Extensive wetland loss and nutrient-enhanced eutrophication occur across the Mississippi River delta and include newly emergent landscapes, in the early stages of ecological succession, and older landscape formations, with fully developed ecological communities. Here I tested how the anthropogenic effects of a climate-induced vegetation shift, an oil spill, and nitrate-enrichment regulate the principal environmental factors controlling nutrient biogeochemistry in wetland soils at different stages of development throughout the Mississippi River delta. In the older, transgressing Barataria basin, there was no clear effect of the climate-induced species shift from Spartina alterniflora Loisel to Avicennia germinans L. on soil nutrient chemistry. Observed …


Out Of Site But Not Out Of Mind: Submerged Prehistoric Landscapes On The Northwestern Gulf Of Mexico Outer Continental Shelf, Amanda M. Evans Jan 2012

Out Of Site But Not Out Of Mind: Submerged Prehistoric Landscapes On The Northwestern Gulf Of Mexico Outer Continental Shelf, Amanda M. Evans

LSU Doctoral Dissertations

Archaeological sites are more important than simply the artifacts they contain. Locations of human occupation and activity form a pattern that can provide information about perceptions of the landscape, decisions about resources, or preferences. Explaining this “perceived” environment is one of archaeology’s goals in explaining past human behavior. In order to address these goals, archaeologists must first identify elements of the “real” landscape, including the geographical environment, its resources, and evidence of human modification. Only after these real elements have been identified can the perceived environment be explored. On the outer continental shelf of the northwestern Gulf of Mexico, formerly …


Reflections On En-Teaching: Dewey, Heidegger And Lao Tzu, Jie Yu Jan 2012

Reflections On En-Teaching: Dewey, Heidegger And Lao Tzu, Jie Yu

LSU Doctoral Dissertations

Reflecting on my past two unsettling journeys of teaching in China and America produces questions about the teaching of truth in chapter one. The question of truth as it relates to the teacher’s role in the classroom raises not only issues of what and how we should teach, but challenges the very purpose of teaching. When I explored Martin Heidegger’s phenomenological perspective on (un)truth for insights into taken-for-granted assumptions about education and the purposes of teaching and learning, I noticed a strong resonance between his notion of “clearing” and the essential spirit of Taoism, “the Tao of inaction.” This led …


Country Of Illusion: Imagined Geographies And Transnational Connections In F. Scott Fitzgerald's America, Charles Mitchell Frye Iii Jan 2012

Country Of Illusion: Imagined Geographies And Transnational Connections In F. Scott Fitzgerald's America, Charles Mitchell Frye Iii

LSU Doctoral Dissertations

The two decades between World Wars I and II were a remarkably isolationist, xenophobic period in the history of American politics and culture. In the era’s literature, however, some US authors repurposed regional writing as a medium for rethinking conservative nationalism and for imagining their country’s place in the emerging global community. F. Scott Fitzgerald, whose career successes and failures mirrored the parabolic national pattern of Boom and Bust, was one such author. Though his works have seldom been interpreted through a regionalist lens, Fitzgerald lived in and wrote about every major American section, often planting tropes of transregional and …


Single-Molecule Detection Of Molecular Beacons Generated From Ldr On Thermoplastic Microfluidic Device For Bioanalysis, Zhiyong Peng Jan 2012

Single-Molecule Detection Of Molecular Beacons Generated From Ldr On Thermoplastic Microfluidic Device For Bioanalysis, Zhiyong Peng

LSU Doctoral Dissertations

Current clinical techniques for nucleic acid detection and analysis often involve PCR, lacking adequate specificity or sensitivity to meet the stringent requirements in certain applications. This research aims to develop an innovative molecular assay and the associated hardware to rapidly signal the presence of certain targets using reporter sequence found in their genome without requiring PCR. This assay coupled the sensitivity of single-pair fluorescence resonance energy transfer (spFRET) with the specificity of ligase detection reaction (LDR) to provide near real-time readout of target biomarkers. Heightened concerns on potential bioterrorism threats, such as rapid dissemination of pathogenic bacteria or viruses into …


The Utilization Of Chemical Communication By Three Species Of Ghost Shrimp, Callichirus Islagrande, Callichirus Major, And Lepidophthalmus Louisianensis, And The Transport Of Chemical Cues Within And Between Burrows, Julie Emily Prerost Jan 2012

The Utilization Of Chemical Communication By Three Species Of Ghost Shrimp, Callichirus Islagrande, Callichirus Major, And Lepidophthalmus Louisianensis, And The Transport Of Chemical Cues Within And Between Burrows, Julie Emily Prerost

LSU Doctoral Dissertations

A multidisciplinary study of the factors affecting the potential use of chemical cues by three species of infaunal shrimp was performed in three parts. A set of modified y-maze choice experiments were performed to establish the ability of three species of ghost shrimp, Callichirus islangrande, Callichirus major, and Leptidophthalmus louisianensis, to detect conspecifics via chemical cue. The time budgets for the detection of conspecifics chemical cues differed significantly from controls (no cue) for both animal cues and odor only cues indicating that all three species were able to detect the difference in sex of conspecific chemical cues regardless of cue …


Nitrogen And Carbon Export To The Gulf Of Mexico By The Atchafalaya River, A Major Distributary Of The Mississippi River, April Elizabeth Bryantmason Jan 2012

Nitrogen And Carbon Export To The Gulf Of Mexico By The Atchafalaya River, A Major Distributary Of The Mississippi River, April Elizabeth Bryantmason

LSU Doctoral Dissertations

Summer hypoxia in the Northern Gulf of Mexico has been attributed to large nutrient inputs, especially nitrate-nitrogen, from the Mississippi-Atchafalaya River system. The 2008 Gulf Hypoxia Action Plan calls for river corridor wetland restoration to reduce nitrate loads, but it is largely unknown how effective riverine wetland systems in the lower Mississippi River (MR) are for nitrate removal. This dissertation research examined nitrate and carbon export from the Atchafalaya River (AR) to: (1) determine nitrate processing by a river swamp basin under varied seasons, (2) investigate nitrate retention and processing in the AR during a major flood event, and (3) …