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Louisiana State University

2009

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Fabrication, Bonding, Assembly, And Testing Of Metal-Based Microchannel Devices, Fanghua Mei Jan 2009

Fabrication, Bonding, Assembly, And Testing Of Metal-Based Microchannel Devices, Fanghua Mei

LSU Doctoral Dissertations

Microsystem technologies are believed to be an important part of the contemporary technological foundation and are becoming a commercially significant specialty area in manufacturing. The design and fabrication of microscale engineering structures has the potential of generating revolutionary changes in many products over a wide range of industrial sectors. Metal-based microchannel heat exchangers (MHEs) promise high heat transfer coefficients together with mechanical robustness, and are of interest for a wide range of applications. Fabrication technologies capable of creating high-aspect-ratio microscale structures (HARMSs) in metals such as Cu at low cost and high throughput are of particular interest. Likewise, simple and …

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Women And Science In Development: A Longitudinal Analysis Of Gender, Networks, And Information Technology In Ghana, Kenya, And India, Beverly Paige Miller Jan 2009

Women And Science In Development: A Longitudinal Analysis Of Gender, Networks, And Information Technology In Ghana, Kenya, And India, Beverly Paige Miller

LSU Doctoral Dissertations

This dissertation examines the gendered nature of the scientific career for researchers in universities and national research institutes in Ghana, Kenya, and Kerala India. Employing panel data, I analyze three issues related to the diffusion of ICTs in the scientific communities of less developed areas: 1) access; 2) interaction; 3) and involvement. More specifically, I examine the way in which human capital, family structure, travel experiences, contextual factors, and technological antecedents interact with gender to influence access to and use of personal computers, email, and the Web. From there, I incorporate technological behavioral changes to predict interaction within professional networks. …

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Do Tops Eligibility Requirements Predict In-System College Retention?, Jason J. Droddy Jan 2009

Do Tops Eligibility Requirements Predict In-System College Retention?, Jason J. Droddy

LSU Doctoral Dissertations

The Taylor Opportunity Program for Students (TOPS) is a state-funded, merit-based scholarship codified into Louisiana state law in 1997. More than $1 billion in awards have been distributed since the program’s inception. By 2006, eligibility for TOPS required a 2.5 high school grade point average on a legislatively specified 16.5-unit college preparatory curriculum, and a minimum ACT score equivalent to the average of the prior year’s test takers. These rules were believed to promote greater academic preparedness resulting in higher college retention rates. Only recently has the six-year graduation rate for Louisiana’s public universities passed the 30% mark. Since TOPS’ …

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Impulsive Control Systems, Wei Cai Jan 2009

Impulsive Control Systems, Wei Cai

LSU Doctoral Dissertations

Impulsive control systems arose from classical control systems described by differential equations where the control functions could be unbounded. Passing to the limit of trajectories whose velocities are changing very rapidly leads to the state vector to "jump", or exhibit impulsive behavior. The mathematical model in this thesis uses a differential inclusion and a measure-driven control, and it becomes possible to deal with the discontinuity of movements happening over a small interval. We adopt the formulism of impulsive systems in which the velocities are decomposed by the slow and fast ones. The fast time velocity is expressed as the multiplication …

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Micro Characterization Of Deformations In Granular Materials During Shear, Alsidqi Hasan Jan 2009

Micro Characterization Of Deformations In Granular Materials During Shear, Alsidqi Hasan

LSU Doctoral Dissertations

One of the greatest challenges in studying the engineering behavior of granular materials is the lack of tools for an unobstructed view of a large quantity of microscopic particles. This dissertation presents a thorough characterization of deformations in sheared granular materials. The investigation involves experimental programs, utilization of computed tomography (CT) techniques, and application of Distinct Element Method (DEM). The investigation was conducted at multi-scale (macroscopic, mesoscopic, and microscopic) to better understand the physical properties and constitutive behavior of granular materials during shear. The experiments include conducting a series of axisymmetric triaxial, miniature axisymmetric triaxial, and biaxial experiments. They were …

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Predicting Performance On High Stakes Testing: Validity And Accuracy Of Curriculum-Based Measurement Of Reading And Writing, Marie Young Henderson Jan 2009

Predicting Performance On High Stakes Testing: Validity And Accuracy Of Curriculum-Based Measurement Of Reading And Writing, Marie Young Henderson

LSU Doctoral Dissertations

The purpose of the current investigation was to determine which curriculum-based measures of written expression demonstrated adequate technical characteristics and provided useful information towards predicting performance on a state-standardized assessment. Data collected from 124 third grade students was used for the study. Curriculum-based measures of reading and writing collected three times within the school year were utilized as the independent variables for predicting the dependent variables. Writing samples were scored using 9 indices of writing. Results from a state standardized assessment (iLEAP) were used as the dependent variables. The study found reliability coefficients for writing indices to be consistent with …

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Collpas As Activity Hotspots For Frugivorous Bats (Stenodermatinae) In The Peruvian Amazon: Underlying Mechanisms And Conservation Implications, Adriana Bravo Ordonez Jan 2009

Collpas As Activity Hotspots For Frugivorous Bats (Stenodermatinae) In The Peruvian Amazon: Underlying Mechanisms And Conservation Implications, Adriana Bravo Ordonez

LSU Doctoral Dissertations

In western Amazonia, large numbers of frugivorous bats regularly visit natural forest clearings known locally as collpas (also called clay licks or mineral licks). Bats arrive at collpas to drink water that has accumulated in depressions created by larger mammals that consume soil. Although collpa visitation by bats appears relatively common in western Amazonia, little is known about its causes and its ecological implications. In this dissertation I describe general and seasonal patterns of collpa visitation by frugivorous bats in the Peruvian Amazon, and I investigate potential explanations for this unique behavior. Regardless of season, collpas seem to be activity …

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An Analysis Of The Impact Of The Eu Sugar Policy Reform On Acp Countries: A Quota Market Framework, Liliane Kiswendsida Zoungrana Jan 2009

An Analysis Of The Impact Of The Eu Sugar Policy Reform On Acp Countries: A Quota Market Framework, Liliane Kiswendsida Zoungrana

LSU Doctoral Dissertations

The pressures for reform within the World Trade Organization have led to the European Union (EU) reforming its sugar policy with a price cut phased from 2006 and scheduled to end in 2009. The reform will have an impact on the sugar protocol African Caribbean and Pacific (ACP) countries that have a preferential market access to the European Union with a protected price. This study investigates the effect of EU sugar policy reform has on these ACP sugar countries. First, it examines how the protocol countries’ sugar supply and demand determinants. While the determinants of supply in some countries performed …

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Function Spaces, Wavelets And Representation Theory, Jens Gerlach Christensen Jan 2009

Function Spaces, Wavelets And Representation Theory, Jens Gerlach Christensen

LSU Doctoral Dissertations

This dissertation is concerned with the interplay between the theory of Banach spaces and representations of groups. The wavelet transform has proven to be a useful tool in characterizing and constructing Banach spaces, and we investigate a generalization of an already known technique due to H.G. Feichtinger and K. Gröchenig. This generalization is presented in Chapter 3, and in Chapters 4 and 5 we present examples of spaces which can be described using the theory. The first example clears up a question regarding a wavelet characterization of Bergman spaces related to a non-integrable representation. The second example is a wavelet …

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Physical Layer Security In Wireless Networks: Intelligent Jamming And Eavesdropping, George Traian Amariucai Jan 2009

Physical Layer Security In Wireless Networks: Intelligent Jamming And Eavesdropping, George Traian Amariucai

LSU Doctoral Dissertations

This work aims at addressing two critical security issues residing in the physical layer of wireless networks, namely intelligent jamming and eavesdropping. In the first two chapters we study the problem of jamming in a fixed-rate transmission system with fading, under the general assumption that the jammer has no knowledge about either the codebook used by the legitimate communication terminals, or the source’s output. Both transmitter and jammer are subject to power constraints which can be enforced over each codeword (peak) or over all codewords (average). All our jamming problems are formulated as zero-sum games, having the probability of outage …

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Leadership Survival And The Process Of Economic Integration, Schuyler Richard Porche Jan 2009

Leadership Survival And The Process Of Economic Integration, Schuyler Richard Porche

LSU Doctoral Dissertations

The central contribution of this dissertation to political science is explaining the role of leadership survival theory in shaping the political process of initiation, broadening, deepening, and failure of economic integration agreements by nation states. The empirical research involves the creation of a dataset recording changes in economic integration for the period 1950-1999 and utilizing advanced quantitative methods to study the process. Most existing research focuses on the initiation of trade agreements. I demonstrate that the process of economic integration agreements among polities is shaped by iterated political interaction at both the domestic and international levels. The critical test in …

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Task Scheduling And Placement For Reconfigurable Devices, Mostafa Elbidweihy Jan 2009

Task Scheduling And Placement For Reconfigurable Devices, Mostafa Elbidweihy

LSU Doctoral Dissertations

Partially reconfigurable devices allow the execution of different tasks at the same time, removing tasks when they finish and inserting new tasks when they arrive. This dissertation investigates scheduling and placing real-time tasks (tasks with deadline) on reconfigurable devices. One basic scheduler is the First-Fit scheduler. By allowing the First-Fit scheduler to retry tasks while they can satisfy their deadlines, we found that its performance can be enhanced to be better than other schedulers. We also proposed a placement idea based on partitioning the reconfigurable area into regions of various widths, assigning a task to a region based on its …

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The Fate And Transport Of Light Petroleum Hydrocarbons In The Lower Mississippi River Delta, Samantha Nicole Danchuk Jan 2009

The Fate And Transport Of Light Petroleum Hydrocarbons In The Lower Mississippi River Delta, Samantha Nicole Danchuk

LSU Doctoral Dissertations

Important processes governing the fate and transport of light petroleum hydrocarbons in the Lower Mississippi River and other river delta systems are not adequately represented in existing oil spill models. In response, three methods were introduced to include the effects of dynamic annual discharges and variation of shoreline type on shoreline retention and re-floatation and the potential of oil- mineral aggregate formation based contributing environmental factors. Parcel tracking was used, in conjunction with detailed shoreline types correlated to flow rate, to evaluate the benefits of using multiple shoreline re-floatation half lives correlated to shoreline type instead of a single half …

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Compilation And Scheduling Techniques For Embedded Systems, Hassan Salamy Jan 2009

Compilation And Scheduling Techniques For Embedded Systems, Hassan Salamy

LSU Doctoral Dissertations

Embedded applications are constantly increasing in size, which has resulted in increasing demand on designers of digital signal processors (DSPs) to meet the tight memory, size and cost constraints. With this trend, memory requirement reduction through code compaction and variable coalescing techniques are gaining more ground. Also, as the current trend in complex embedded systems of using multiprocessor system-on-chip (MPSoC) grows, problems like mapping, memory management and scheduling are gaining more attention. The first part of the dissertation deals with problems related to digital signal processors. Most modern DSPs provide multiple address registers and a dedicated address generation unit (AGU) …

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Joseph Messner's Organ Music: Evolution Of A Style, Julie Powell Rozman Jan 2009

Joseph Messner's Organ Music: Evolution Of A Style, Julie Powell Rozman

LSU Doctoral Dissertations

Joseph Messner (1893-1969) achieved fame in Europe for his contributions to the sacred concerts of the Salzburg Festspiele following World War II. In his early career, however, Messner earned initial acclaim as a recitalist and renowned improviser on the organ. Messner composed and published several organ works prior to World War II which contain style elements of late-romanticism and an emerging neoclassicism. This paper analyses the works in regards to form, stylistic elements, and performance issues in addition to establishing the historical contexts from which they originated.

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The Study Of Sediment Dynamics In A Shallow Estuary Using Integrated Numerical Modeling And Satellite Remote Sensing, Haihong Zhao Jan 2009

The Study Of Sediment Dynamics In A Shallow Estuary Using Integrated Numerical Modeling And Satellite Remote Sensing, Haihong Zhao

LSU Doctoral Dissertations

The primary objective of the study is to develop an effective tool to investigate the resuspension, deposition and transport of mixed cohesive and non-cohesive sediments in an estuary. The research has integrated 1) statistical analyses of the primary forcing, 2) numerical models for hydrodynamics, surface waves and sediment transport, and 3) the MODIS (Moderate Imaging Spectroradiometer) remotely sensed imagery, to investigate hydrodynamics and sediment dynamics in Mobile Bay, Alabama. First, based on long-term meteorological and tidal observations, statistical analyses have been conducted to predict extreme values of winds and water levels at different return periods in the estuary. Application of …

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Evolution Of Vocal Signals In A Neotropical Avian Lineage, Brian J. O'Shea Jan 2009

Evolution Of Vocal Signals In A Neotropical Avian Lineage, Brian J. O'Shea

LSU Doctoral Dissertations

In this dissertation I explored variation in vocalizations of the avian genus Synallaxis (Passeriformes: Furnariidae) and the use of vocal characters to determine phylogenetic relationships at the species level. Vocalizations of suboscine passerines have recently gained favor as a proxy for genetic material in systematic studies; however, individual and geographic variation are both widespread in suboscines, complicating the definition and analysis of vocal characters. This is particularly true for species that have simple, phylogenetically conserved vocalizations. Moreover, the use of vocal characters in suboscine systematics depends on the confident assessment of homologous vocalizations, as well as a thorough understanding of …

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Children's Production Of Verbal -S By Dialect Type And Clinical Status, Lesli H. Cleveland Jan 2009

Children's Production Of Verbal -S By Dialect Type And Clinical Status, Lesli H. Cleveland

LSU Doctoral Dissertations

The study examined children’s use of verbal –s marking (e.g., he walks) in two nonmainstream dialects of English, African American English (AAE), and Southern White English (SWE). Verbal –s marking was of interest because there are gaps in the literature about the nature of this structure within and across typically developing children who speak AAE and SWE and about the nature of this structure in AAE- and SWE-speaking children with specific language impairment (SLI). To address these gaps, children’s verbal –s marking was examined as a function of their dialect and clinical status and as a function of a number …

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Iron Mediated Pecipitation Of Phenol: Protein Aggregates From Sugar Cane Juice, Lee R. Madsen Ii Jan 2009

Iron Mediated Pecipitation Of Phenol: Protein Aggregates From Sugar Cane Juice, Lee R. Madsen Ii

LSU Doctoral Dissertations

The Louisiana cane sugar industry is moving toward a vertically integrated arrangement where raw sugar producers will have an interest in refining. In the sugar refining process, raw sugar is affined to remove ~50 % of the color. The new refinery that will be built in Louisiana, however, will not include affining stations. To reduce costs of refining, either affining stations will need to be installed at each mill or new technologies that provide equivalent color reduction (~50% or ~750 IU) need to be implemented. As part of this dissertation a new technology for color reduction at raw sugar mills …

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A Discrete Model Of Guided Modes And Anomalous Scattering In Periodic Structures, Natalia Grigoryevna Ptitsyna Jan 2009

A Discrete Model Of Guided Modes And Anomalous Scattering In Periodic Structures, Natalia Grigoryevna Ptitsyna

LSU Doctoral Dissertations

We study a discrete prototype of anomalous scattering associated with the interaction of guided modes of a periodic scatterer and plane waves incident upon the scatterer. The transmission anomalies arise because of the non-robustness of a guided mode, a mode that exists only at a specific frequency and wave number pair. The simplicity of the discrete prototype allows one to make certain explicit calculations and proofs, and to examine details of important resonant phenomena of the open wave guides. The main results are (1) a formula for transmission anomalies near a non-robust guided mode with rigorous error estimates that extends …

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Molecular, Statistical And Genetic Analyses Of Complex Agronomic Traits In Rice, Samuel Agbayani Ordonez Jr. Jan 2009

Molecular, Statistical And Genetic Analyses Of Complex Agronomic Traits In Rice, Samuel Agbayani Ordonez Jr.

LSU Doctoral Dissertations

Novel molecular and statistical approaches are needed for identification of DNA markers associated with complex traits in rice. The first research objective was to evaluate mixed-model and multiple regression approaches for their ability to identify molecular markers associated with complex traits in rice. A combined mixed model and multiple regression approach was optimal for selecting the smallest number of DNA markers associated with relatively high R2 values and for consistency with previous mapping studies. Support Vector Regression (SVR) was evaluated in the second research objective for the ability to generate high levels of accuracy and power for markers associated with …

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Mais, I Sin In French, I Gotta Go To Confession In French: A Study Of The Language Shift From French To English Within The Louisiana Catholic Church, Emilie Gagnet Leumas Jan 2009

Mais, I Sin In French, I Gotta Go To Confession In French: A Study Of The Language Shift From French To English Within The Louisiana Catholic Church, Emilie Gagnet Leumas

LSU Doctoral Dissertations

To study language change within South Louisiana Catholic Church, I examined the sacramental registers of more than 250 churches, the country of origin of 1043 priests, the parish visitation reports of 37 individual churches and 160 original data cards from 1906 Census of Religious Bodies. Metalinguistic elements were collected from various files available at the archives. This study reveals the complex nature of the language switch from French to English, a network structure of top down management and elements of change in each community of practice which pressured the other levels. It is specific to the Louisiana Catholic population, the …

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Assessing Linkages Between Petroleum Platforms And Pelagic Fishes Using Telemetry With Emphasis On Blue Runner (Caranx Crysos), Harmon Brown Jan 2009

Assessing Linkages Between Petroleum Platforms And Pelagic Fishes Using Telemetry With Emphasis On Blue Runner (Caranx Crysos), Harmon Brown

LSU Doctoral Dissertations

Petroleum platforms number greater than 4,200 in the Gulf of Mexico and Caranx crysos (blue runner) is one of the most abundant fish species around these platforms. Forty-six blue runner were tagged with acoustical transmitters in August 2005, though the study was terminated prematurely due to the impending arrival of Hurricane Katrina. Nineteen blue runner were tagged in September 2006 and tracked for up to two months. Blue runner exhibited limited site fidelity around the platforms in 2005. The home range of twenty-three blue runner was calculated in 2005. A significant difference was found between the fork length of the …

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Genome-Wide Mapping Of Beaf Binding Sites In Drosophila Links Beaf To Transcription, Nan Jiang Jan 2009

Genome-Wide Mapping Of Beaf Binding Sites In Drosophila Links Beaf To Transcription, Nan Jiang

LSU Doctoral Dissertations

Gene expression is regulated by the chromatin environment and various cis-regulatory elements. Gene activators and repressors target specific regulatory elements in the genome to regulate nearby genes. But they function only in limited regions called domains. In each domain, genes are regulated independently without interference from outside. Boundary elements (insulators), binding sites for insulator proteins, are proposed to separate neighboring domains. One function of insulators is to block interactions between an enhancer and a promoter if positioned between them; the second function is to block the spreading of certain chromatin states along chromatin. BEAF-32 (with two 32 kDa variants: BEAF-32A …

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An Analysis Of The Social Networks Of Local Television Reporters, Lisa R. Honore Jan 2009

An Analysis Of The Social Networks Of Local Television Reporters, Lisa R. Honore

LSU Doctoral Dissertations

This study analyzed the personal and professional networks of four local television reporters using social network analysis methodology. Network analysis was carried out to the tertiary level allowing examination of demographic data for 773 individuals in the reporter networks. Analysis was conducted through the lens of media norms and routines and the sociological principle of homophily that states people are more likely to associate with people like themselves. Using as a guide, norms and routines and homophily literature as well as studies about the portrayal of minorities, the study examines how the social networks of reporters can determine how communities …

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The Definition, Creation, And Evolution Of Buyer-Seller Relationships, Anna Maria Walz Jan 2009

The Definition, Creation, And Evolution Of Buyer-Seller Relationships, Anna Maria Walz

LSU Doctoral Dissertations

The theoretical and practical importance of relational exchange is well known. However, customers are often annoyed at companies’ relationship building attempts. In addition, the literature has three core problems: (1) the relational concept is not well defined; (2) little research has accounted for relationship dynamics; and (3) relational constructs’ conceptualizations have become ambiguous. The purpose of this dissertation is to build an integrative and comparative framework that not only delineates relationship stages, but also identifies the unique roles of all relational forms (e.g., firm-firm). Specifically, three research questions are addressed: (1) How is a relationship defined? (2) How is a …

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Nitric Oxide Cytotoxicity And Functions Of Iron-Sulfur Enzymes In Escherichia Coli, Binbin Ren Jan 2009

Nitric Oxide Cytotoxicity And Functions Of Iron-Sulfur Enzymes In Escherichia Coli, Binbin Ren

LSU Doctoral Dissertations

Iron-sulfur proteins are ubiquitous in biological processes. Here we report that NO, a physiological free radical, can effectively inhibit cell growth of Escherichia coli in minimal medium under anaerobic growth conditions. Fractionation of the cell extracts obtained from NO-exposed cells shows a broad distribution of the protein-bound dinitrosyl-iron complexes (DNICs) formed by NO. On the other hand, the cell growth of E. coli can be restored when NO-exposed cells are either supplemented with the branched-chain amino acids (BCAAs) anaerobically or returned to aerobic growth conditions. It turns out that dihydroxyacid dehydratase (IlvD), an iron-sulfur enzyme essential for the BCAAs biosynthesis, …

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Large Eddy Simulation Of Turbulent Premixed Combustion In Gas Turbines, Ashoke De Jan 2009

Large Eddy Simulation Of Turbulent Premixed Combustion In Gas Turbines, Ashoke De

LSU Doctoral Dissertations

An artificially Thickened Flame (TF) approach based on LES framework is used to model the turbulent premixed combustion in gas turbine combustors. A number of variants of the Thickened Flame approach including a modified version of TF model have been studied in details. In the TF model, the flame front is artificially thickened to resolve on LES computational grid. With this approach, reaction rate modeling does not require any ad-hoc closure assumptions. However, suitable modifications have to be made to compensate for flame thickening. To verify the predictive capability of the models, a stoichiometric methane-air flame on Bunsen burner type …

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Non-Canonical Retrotransposon Insertions: Alternative Pathways To Integration, Deepa Latha Srikanta Jan 2009

Non-Canonical Retrotransposon Insertions: Alternative Pathways To Integration, Deepa Latha Srikanta

LSU Doctoral Dissertations

The majority of retrotransposons, mobile elements which move around the genome using an RNA intermediate, insert into their host genomes using target-primed reverse transcription (TPRT). Two of the most well-studied types of active retrotransposons in primates are L1s (Long Interspersed Element-1) and Alu elements. Both preferentially insert using TPRT, and these insertions can create genomic rearrangements and contribute to genome fluidity. Recent analyses have shown that L1s and Alu elements can insert using a variety of non-canonical mechanisms, including a DNA double-strand break repair pathway. Increased understanding of the mechanisms by which mobile elements insert into host genomes can help …

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Environmental Effects On Adolescents Exposed To Hurricane Katrina, Karen Laslie Davidson Jan 2009

Environmental Effects On Adolescents Exposed To Hurricane Katrina, Karen Laslie Davidson

LSU Doctoral Dissertations

Adolescents in New Orleans were displaced by hurricane Katrina and returned to find their city devastated by this natural disaster. Although many studies have found a relationship between hurricane exposure and development of psychopathology, the current study evaluated this relationship within the context of protective and risk factors. Specifically, the current study evaluated whether community violence, parent support, and peer support moderated the relationship between hurricane exposure and adolescent PTSD or depression. Results found no relationship between hurricane exposure and adolescent depression. Although there was a main effect for hurricane exposure and PTSD, the proposed variables did not moderate this …

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